Abstract:
A moisture management liner device for a prosthetic socket may include an elongate, cup-shaped, elastomeric member and multiple fluid transport strips. The elastomeric member may include a first material and may extend from an open proximal end to a substantially closed distal end. The substantially closed distal end may include a fluid exit aperture to allow fluid to pass out of the liner device. The fluid transport strips may include a second material and may be disposed at spaced-apart intervals around a circumference of an internal surface of the elastomeric member, over at least a distal portion of the elastomeric member. The fluid transport strips may be configured to facilitate passage of fluid out of the liner device through the fluid exit aperture.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority to U.S. Provisional Patent Application No. 61/837,778 of Hurley and Williams, entitled “A Prosthetic Socket Liner With Moisture Management Features” and filed on Jun. 21, 2013, and to U.S. Provisional Patent Application No. 61/901,618 of Hurley and Williams, entitled “A Prosthetic Socket and Liner With Moisture Management Capability” and filed on Nov. 8, 2013. 
       INCORPORATION BY REFERENCE 
       [0002]    All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each such individual publication or patent application were specifically and individually indicated to be so incorporated by reference. 
     
    
     TECHNICAL FIELD 
       [0003]    The embodiments described herein relate to medical devices and methods. More specifically, the embodiments relate to a moisture management system for use in a prosthetic socket. 
       BACKGROUND 
       [0004]    Polymeric prosthetic socket liners are widely used as an interface between the surface of a residual limb and a prosthetic socket that grasps the residual limb and provides continuity of function between the residual limb and more distal prosthetic components. These socket liners provide padding or pressure distribution surfaces that create greater comfort for the patient, and they also participate in suspension of the prosthetic socket on the residual limb. Suspension usually relies both on the tenacity with which the liner maintains its grasp on the residual limb and on the tenacity with which the socket maintains its grasp on the liner. Satisfactory performance of the prosthesis as a whole depends on many factors, but the quality of the fit of the socket on the residual limb, an optimal liner solution, and the overall quality of suspension of the socket are all very important. 
         [0005]    Polymeric prosthetic liners typically include materials such as silicone, urethane, and thermoplastic elastomer gels in the form of blends and block copolymers, as well mineral oils. These liners are conformable and, when appropriately sized, comfortable and easily donned and removed. Liners fit closely against the skin, and may further be subjected to internal vacuum pressure that ensures a close fit, and if the fit creates an effective seal, may create a subatmospheric pressure internal to the liner. These features contribute to the liner&#39;s role in suspension of the prosthetic socket, but they also create a closed environment that supports the buildup of body-generated moisture and heat around the residual limb. Excess heat and moisture are detrimental to the health of the residual limb, as they are damaging to skin integrity and ideal for bacterial colonization. 
         [0006]    Although various attempts have been made to remove moisture from prosthetic liners, it has been challenging to remove moisture while still providing adequate suspension force. Thus, improved prosthetic socket liners with moisture management features are still desired. 
       SUMMARY OF THE TECHNOLOGY 
       [0007]    Various embodiments of a moisture management prosthetic socket liner system may include a number of moisture management features as well as methods for removing moisture from the interior of a liner when it is being worn by a patient. Although moisture management features described herein are primarily integrally included within the structure of the liner garment (or “liner” or “liner device”), some aspects of moisture management may also be included in the prosthetic socket itself. Embodiments of the moisture managing liner garment are sized and shaped to accommodate a distal portion of a residual limb. Embodiments of a prosthetic socket frame and a liner garment are mutually sized and configured such that the socket accommodates the moisture managing liner garment. The garment includes an internal surface and an external surface, as well as a proximal portion and a distal portion. The internal surface is that which comes into direct contact with the skin of the patient&#39;s residual limb. The external surface of the garment may come into contact with structural elements of the prosthetic socket, or it may be exposed directly to the ambient atmosphere, depending on the particular structure of the socket. The proximal portion of the garment is open to receive the residual limb, and the distal portion is distally closed. 
         [0008]    In one aspect, a moisture management liner device for a prosthetic socket may include: an elongate, cup-shaped, elastomeric member, comprising a first material and extending from an open proximal end to a substantially closed distal end, where the substantially closed distal end comprises a fluid exit aperture to allow fluid to pass out of the liner device; and multiple fluid transport strips, comprising a second material and disposed at spaced-apart intervals around a circumference of an internal surface of the elastomeric member, over at least a distal portion of the elastomeric member, where the fluid transport strips are configured to facilitate passage of fluid out of the liner device through the fluid exit aperture. 
         [0009]    In some embodiments, the elastomeric member may be a contiguous layer. Some embodiments may further include an array of radially-directed pores extending from the internal surface to an external surface of the elastomeric member. In some embodiments, the array of radially-directed pores is disposed proximal to the longitudinally aligned fluid transport strips. Some embodiments may further include an outer fluid transport substrate disposed over at least a portion of an external surface of the elastomeric member to facilitate passage of fluid out of the liner device through the pores. In some embodiments, the fluid transport strips comprise a wicking fabric. In alternative embodiments, the fluid transport strips comprise a breathable mesh fabric. 
         [0010]    In some embodiments, the liner device may further include a valve and/or a pump attached to the device to facilitate unidirectional fluid flow out of the liner device. In some embodiments, the liner device may further include a distally projecting outlet in fluid communication with the fluid exit aperture and a prosthetic socket support element, comprising a centrally positioned annular locking mechanism clampable around the distally-projecting outlet. Optionally, the distally projecting outlet is also in fluid communication with a fluid residing in an interfacing layer between the liner device and a prosthetic socket to which the liner device is attached. In some embodiments, the liner device may further include a reservoir, comprising an inlet into which the distally projecting outlet of the liner device drains and an outlet, comprising a one-way valve biased toward allowing fluid to escape the reservoir. In some embodiments, the liner device may further include a reservoir coupled to the liner device to capture fluid from the device and from an interfacing space between the device and the residual limb and a pump in communication with the reservoir and configured to draw fluid from the reservoir. In some embodiments, at least a proximal portion of the internal surface of the elastomeric member is configured to form an airtight seal with the residual limb. 
         [0011]    In another aspect, a moisture management liner device for a prosthetic socket may include: an elongate, cup-shaped, elastomeric member, comprising a first material, an internal surface and an external surface, and extending from an open proximal end to a substantially closed distal end, wherein the substantially closed distal end comprises a fluid exit aperture to allow fluid to pass out of the liner device; a fluid transport substrate disposed over at least a distal portion of at least one of the internal surface or the external surface of the elastomeric member, wherein the fluid transport substrate comprises a second material; and an array of radially-directed pores extending through the elastomeric member from the internal surface to the external surface, to allow fluid to pass out of the liner device. 
         [0012]    In some embodiments, a first layer of the fluid transport substrate is disposed on the external surface of the elastomeric member, and at least some of the pores extend through the first layer of the fluid transport substrate. In some embodiments, a second layer of the fluid transport substrate is disposed on the internal surface of the elastomeric layer. Optionally, at least some of the pores may extend through the elastomeric member, the first layer and the second layer. 
         [0013]    In another aspect, a moisture management liner device for a prosthetic socket may include: an elongate, cup-shaped, elastomeric member, comprising a first material and extending from an open proximal end to a substantially closed distal end; a fluid transport substrate disposed between the internal and external layers of the elastomeric member along at least a distal portion of the elastomeric member, wherein the fluid transport substrate comprises a second material; and an array of radially-directed pores extending through at least the internal layer of the elastomeric member to allow fluid to pass from an internal surface of the internal layer to the fluid transport substrate. The elastomeric member may include an internal layer, an external layer and a fluid exit aperture at the distal end for allowing fluid to pass out of the device. 
         [0014]    In some embodiments, at least some of the pores extend through the external layer of the elastomeric member. In some embodiments, the fluid transport substrate comprises a wicking fabric. Alternatively, the fluid transport substrate may comprise a breathable mesh fabric. Optionally, the device may further include a valve and/or a pump attached to the device to facilitate unidirectional fluid flow out of the liner device. 
         [0015]    In another aspect, the liner garment may include an elastomeric portion and a fluid transport substrate portion. These portions may overlap or physically coexist within the fabric of the liner. In some embodiments, the elastomeric portion comprises a substantially contiguous layer, at least in the proximal portion of the garment. In some embodiments, the elastomeric portion is continuous throughout the garment. Embodiments may further include at least one distal fluid exit port disposed within the distal portion of the garment. 
         [0016]    In one embodiment of the moisture managing liner, the fluid transport substrate is arranged as longitudinal strips disposed on the internal surface of the distal portion of the liner. The internal surface of the garment disposed between the longitudinal strips includes the elastomeric portion. The fluid transport substrate provides a first fluid escape path, distally directed, from a skin surface of the residual limb to an environment external to the liner garment. Optionally, the first fluid escape path may further include an exit from the liner through the distal exit port. 
         [0017]    Some embodiments of a moisture managing liner garment may further include an array of radially-directed pores that penetrate at least the elastomeric portion of the garment. The pores provide a second fluid escape path (in addition to the distally directed fluid escape path noted above) for fluid that accumulates between the residual limb and the garment. The second fluid escape path leads laterally or radially to the external surface of the liner garment. In some embodiments, the array of radially-directed pores is disposed proximal to the longitudinally aligned fluid transport strips. 
         [0018]    In some embodiments of the moisture managing liner garment, the fluid transport substrate may also be disposed on the external surface of the garment. In some embodiments, the fluid transport substrate includes a wicking fabric. In other examples, the fluid transport substrate may include a breathable mesh fabric. In various embodiments, the fluid transport substrate may include valves and/or pumps configured to facilitate unidirectional fluid flow toward the external environment. Some embodiments of the fluid transport substrate itself, however, are freely porous to water and do not exert a bias on the directionality of flow within or across the substrate. In other embodiments, the fluid transport substrate may exert a bias on the directionality of flow within or across the substrate. 
         [0019]    Embodiments of the moisture management technology may further include features that are associated with or attached to a distal socket structure, such as a distal cup or distal base. The distal socket structure may include a centrally positioned annular locking mechanism that is configured to be clamped around the distally projecting outlet of the drainage port. In some embodiments, the drainage port is in fluid communication with fluid (air and water vapor) that has accumulated in an interfacing layer between the residual limb and the liner garment when a patient is wearing the liner. More particularly, in some embodiments, the annular locking mechanism can clamp around the distally projecting outlet of the drainage port with sufficient strength that the garment and the distal prosthetic socket structure remain securely attached to each other during normal wear. In typical embodiments, the locking mechanism includes a manually operable release mechanism. Embodiments of the locking and release mechanism are configured to be manually operable by the patient. 
         [0020]    In some embodiments of the moisture management technology, a distal prosthetic socket structure further includes a reservoir for capturing fluid that passes through the distally-projecting drain. This fluid may be drawn from the fluid transport path facilitated by the wicking substrate of the liner and/or it may be drawn from an interfacing space between the residual limb and the liner. In some embodiments, the reservoir has an inlet into which the distally projecting outlet can drain when the conformable garment is disposed within the prosthetic socket. A one-way valve may be disposed in either the distally projecting drain or the reservoir inlet to bias moisture draining from within the garment liner or the space between the liner and the socket into the reservoir. The reservoir may further include an outlet, which may include a one-way valve biased toward allowing fluid to escape the reservoir. 
         [0021]    While some embodiments may take advantage of a passive or gravity driven drainage into the reservoir, some embodiments of the moisture management technology may further include a pump in operable communication with the outlet of the reservoir to draw fluid from the reservoir. In some embodiments, the pump may be electrically powered. In other embodiments, the pump may be mechanically powered, for example by harnessing a small portion of energy provided by body movements of the patient. In one example of a mechanically powered pump used in some embodiments of the moisture management technology, the reservoir includes a mechanism that captures kinetic energy associated with a movement of the patient and directs such energy to drawing fluid from the reservoir. 
         [0022]    In some embodiments of the moisture management technology, the internal surface of the proximal portion of the liner garment comprises only the elastomeric portion; i.e., a circumferential internal region at the proximal-most portion does not include a fluid transport substrate. Such elastomeric internal surface is advantageously disposed and adapted to come into sealing contact with a skin surface of the residual limb, such sealing contact being substantially continuous circumferentially around the residual limb. In various of these embodiments, the sealing contact of the liner garment on the residual limb has sufficient integrity to form an environment within the distal portion of the garment that is closed to a proximally sourced influx of ambient air that, absent such sealing contact, could travel distally beneath the proximal portion of the liner. 
         [0023]    Some of these embodiments of the moisture management technology may further include an evacuatable reservoir in fluid communication with a reservoir and with the environment within the closed distal portion of the liner. Upon at least a partial evacuation of the reservoir, a subatmospheric pressure is created within the reservoir and within an interfacing layer between the residual limb the distal portion of liner. The advantageous result of the subatmospheric pressure is to contribute to the stability or adherence of the moisture management garment liner on the residual limb. 
         [0024]    Some embodiments of a moisture management liner garment for a prosthetic socket may include pores that provide a direct path for moisture within the garment to the external environment. As described above in the context of the first embodiment, this liner second embodiment is sized and shaped to accommodate a distal portion of a residual limb and to be hosted within a prosthetic socket. The moisture managing garment liner embodiment has an internal surface and an external surface, a distal portion and a proximal portion, an elastomeric portion, and a fluid transport substrate portion that is disposed at least on the external surface of the garment. The elastomeric portion forms a substantially contiguous layer throughout the garment. The elastomeric portion has an array of radially-directed pores that extend into the fluid transport substrate on the external surface. The pores provide a fluid escape path for fluid that accumulates between the residual limb and the liner garment. This fluid escape path leads to the external surface of the liner garment. The array of pores may be dispersed in any suitable pattern and throughout the inner surface of the liner except for a pore-free circumferential region at the proximal boundary of the garment. 
         [0025]    In some examples of this moisture management liner embodiment, the fluid transport substrate may be further disposed on the internal surface of the garment. In other examples, the moisture management liner embodiment may further include a distal fluid exit port disposed within the distal portion of the garment. 
         [0026]    Some embodiments of a moisture management liner garment for a prosthetic socket may include a fluid transport substrate sandwiched between an internal and an external elastomeric layer. The moisture managing garment liner embodiment has an internal surface and an external surface, and a distal portion and a proximal portion, an elastomeric portion and a fluid transport substrate portion, and a distal fluid exit port disposed within the distal portion of the garment. 
         [0027]    In this embodiment, the elastomeric portion is arranged such that at least a portion is disposed on an internal layer and an external layer of the liner garment, and the fluid transport substrate is disposed as a channel between the internal and external elastomeric layers. The fluid transport portion forms a channel, a generally distally directed fluid escape path from a skin surface of the residual limb to an external environment. The internal surface of the liner (the internal layer of elastomer) includes open pores that expose the underlying fluid transport portion disposed between the internal and external elastomeric layers. These pores are included in the fluid escape path of this embodiment. Moisture escapes from the space between the residual limb and the liner by way of these pores and enters the fluid transport substrate channel, whereby it flows distally through the fluid transport substrate, ultimately escaping through the distal fluid exit port. 
         [0028]    Embodiments of the technology further include methods of removing fluid from within a prosthetic socket liner. One embodiment of removing moisture or fluid includes providing a prosthetic socket liner with moisture management features and then moving moisture that has accumulated within the liner garment toward the external environment. Several embodiments of a moisture management prosthetic socket liner garment have been described. In brief, such a liner garment includes an internal surface and an external surface, the internal surface circumscribing an interior space; a distal portion and proximal portion; and an elastomeric portion and a fluid transport substrate. The fluid transport substrate forms or is included within a moisture escape path from within the interior of the liner garment to an environment external to the liner garment. Such moisture escape path may be directed to any of (1) the distal portion of the liner garment or (2) radially through the liner. 
         [0029]    In some embodiments of the method, prior to the moving step, the method may include donning the liner garment over a residual limb of a patient, and inserting the residual limb with the donned liner garment into the prosthetic socket. 
         [0030]    In some embodiments, the liner garment further comprises a drain in the distal portion of the garment liner. With such embodiments, moving moisture from within the liner garment toward the external environment may include moving moisture distally, and through the distal drain. 
         [0031]    In some embodiments, the liner garment further comprises an array of pores on the internal surface of the liner garment. With such embodiments, moving moisture from within the liner garment toward the external environment may include moving moisture radially through the array of pores. 
         [0032]    These and other aspects and embodiments will be described more fully below, in relation to the attached drawing figures. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0033]      FIG. 1  is a longitudinal cross-sectional (exposed half-pipe) view of a prosthetic socket liner in which the fluid transport substrate is arranged so that its proximal end terminates below the proximal end of the prosthetic socket, according to one embodiment. 
           [0034]      FIG. 2A  is a longitudinal cross-sectional view of prosthetic socket liner in which the fluid transport substrate is arranged into longitudinal strips, the strips distributed circumferentially such that they are spaced apart, according to one embodiment. 
           [0035]      FIG. 2B  is a top view of the prosthetic socket liner shown in  FIG. 2A , looking proximally into the distal end of the liner, in which the fluid transport substrate is arranged into longitudinal strips, the strips distributed circumferentially such that they are spaced apart. 
           [0036]      FIG. 3  is a longitudinal, cross-sectional view of a prosthetic socket liner configured to provide for the escape of water vapor in a lateral or radial direction with respect to the longitudinal axis of the liner, according to one embodiment. 
           [0037]      FIG. 4  is a longitudinal, cross-sectional view of a prosthetic socket liner configured to provide both for distal movement of moisture and also for lateral or radial escape of moisture, according to one embodiment. 
           [0038]      FIG. 5  is a longitudinal cross-sectional view of a prosthetic socket liner that includes a pattern of macroscopic perforations. 
           [0039]      FIG. 6  is a longitudinal, cross-sectional view of a prosthetic socket liner configured to provide a mechanically assisted removal of moisture from within a space between the patient&#39;s skin and the surrounding socket, according to one embodiment. 
           [0040]      FIG. 7  is a longitudinal, cross-sectional view of a distal portion of a prosthetic socket moisture management liner situated within a socket and including an electric pump driven mechanism that actively withdraws fluid from the reservoir disposed at the base of the socket, according to one embodiment. 
           [0041]      FIG. 8A  is longitudinal, cross-sectional view of a distal portion of prosthetic socket moisture management system embodiment situated within a socket that includes a pumping mechanism driven by the impact of a patient&#39;s stride, according to one embodiment. This view shows the pump prior to the impact of the leg wearing the prosthesis hitting the ground. 
           [0042]      FIG. 8B  is view the moisture management system embodiment shown in  FIG. 7A  at a point during which the stride of a patient is creating an impact that forces compression of a deflectable feature of the pump, the compression causing ejection of accumulated fluid from the pump. 
           [0043]      FIG. 8C  is view the moisture management system embodiment shown in  FIGS. 7A and 7B  at a point the leg that created the impact shown in  FIG. 7B  has now lifted off the ground, allowing the deflectable feature of the pump to return to its undeflected configuration, the pump thereby expanding its internal volume, and drawing in fluid from the distal portion of the moisture management liner. 
           [0044]      FIG. 9A  is a longitudinal cross sectional view of a length of a prosthetic socket moisture management liner embodiment that includes a layer of fluid transport substrate sandwiched within a larger gel layer. 
           [0045]      FIG. 9B  is a cross-sectional view of the prosthetic socket moisture management liner shown in  FIG. 9A . 
           [0046]      FIG. 10  is a partial, cross-sectional view of a moisture management system disposed in a prosthetic socket frame and a socket liner, according to one embodiment. 
           [0047]      FIGS. 11A-11B  are schematic representations of cross-sectional views through a residual limb, a first intervening space, a moisture management liner, a second intervening space, and a prosthetic socket. 
           [0048]      FIG. 12  shows a longitudinal cross sectional view of an embodiment of a prosthetic socket with an embodiment of a prosthetic socket liner disposed therein. 
           [0049]      FIG. 13  is a flow diagram of a method of removing accumulated moisture from within a prosthetic socket fitted with an embodiment of a prosthetic socket liner with moisture management features. 
           [0050]      FIG. 14  is a flow diagram of a method of removing accumulated moisture from within a prosthetic socket fitted with an embodiment of a prosthetic socket liner with moisture management features with a focus on fluid flow paths from (1) a space between the skin of the residual limb the liner, and (2) a space between the liner and the prosthetic socket structure. 
       
    
    
     DETAILED DESCRIPTION 
       [0051]    Embodiments of the disclosed technology include a prosthetic socket liner garment adapted for moisture management and for use in conjunction with a prosthetic socket for a residual limb. Embodiments of the disclosed moisture management technology are typically disposed within a prosthetic socket liner garment. In some embodiments, however, moisture-managing features associated with or incorporated into the garment may also be supported by the prosthetic socket structural components. Prosthetic sockets for which embodiments of the provided socket liner garment are suitable include embodiments of a modular prosthetic socket (as described in US Published App. No. 2013/0123940 and U.S. patent application Ser. No. 14/213,788), as well as any suitable prior art plastic prosthetic socket. 
         [0052]      FIGS. 1-12  show various embodiments of a liner garment that have a similar form factor but vary with regard to their moisture management features.  FIGS. 13 and 14  show embodiments of methods of transporting fluid as enabled by embodiments of the moisture management liner. Liner garment  10  ( FIGS. 1 ,  6 , and  10 ) may be considered a basic embodiment. Liner garment  110  ( FIGS. 2A-2B ) particularly includes fluid transport substrate or wicking strips. Liner garment  210  ( FIG. 3 ) particularly includes lateral pores. Liner garment  310  ( FIG. 4 ) particularly includes both fluid transport strips and lateral pores. Liner garment  410  includes a fluid transport substrate in the form of a breathable fabric. Liner garment  510  ( FIGS. 9A-9B ) particularly includes wicking channels.  FIGS. 7-8C  relate to pumping mechanisms that may be applied to multiple garment liner embodiments. Liner garment  10 . 1  is a generic embodiment of a moisture management liner that calls out no moisture management features in particular, but which is helpful in depicting ( FIGS. 11A and 11B ) the overall context of the liner in relation to spaces adjacent to it (the space between the liner and the limb, and the space between the liner and a prosthetic socket). 
         [0053]    The liner garment embodiments described herein include a proximal portion  16  with an open end and a distal portion  18  with a distal end that is closed except for an optional distal port  40 . Proximal portion  16  and distal portion  18  are general terms; the portions need not be sharply demarcated, and the relative site of demarcation can vary from embodiment to embodiment. The liner garment embodiments have an internal surface  12  that interfaces with the surface of a patient&#39;s residual limb  90  and an external surface  14  that interfaces either directly with the external environment or an aspect of a prosthetic socket into which the liner garment is disposed. Before describing liner garments  10 ,  110 ,  210 ,  310 ,  410 , and  510  in further detail, the technology will be described in general terms. 
         [0054]    Moisture managing liner garment embodiments provide an interfacing surface or space disposed between the skin surface of a patient&#39;s residual limb and the socket structure when the socket is being worn. Embodiments of the liner technology include features adapted to reduce or remove moisture that accumulates within the interfacing space between the patient&#39;s skin and the socket structure. Reduction or minimization of accumulated moisture occurs by conveying moisture from the interfacing space to the exterior environment by various escape routes, as described in detail below. 
         [0055]    Embodiments of the prosthetic socket liner have a central longitudinal axis that aligns (or substantially aligns) with the longitudinal axis of the residual limb on which the prosthetic socket and liner are worn. With reference to the longitudinal axis, embodiments of the liner include a proximal end that is open to receive the residual limb, and a distal end that is closed, to enclose the distal end of the residual limb. Thus, the terms proximal and distal serve as reference terms for the residual limb, for the prosthetic socket, and for embodiments of the liner garment. Further, prosthetic socket liners include an external surface that interfaces either with an inner aspect of the prosthetic socket structure surrounding it, or directly with the ambient atmosphere. Prosthetic socket liners also include an internal surface that interfaces with the skin of the patient&#39;s residual limb. 
         [0056]    Typical embodiments of prosthetic socket liners described herein are flexible or compliant, fitting the residual limb closely, but in a non-restrictive manner. At least a portion of the internal surface of the socket liner embodiments may have a tacky or sticky aspect that provides a degree of traction against the skin that is sufficient to prevent substantial slippage between the liner and the skin. Another portion of the internal surface may include a fluid transport substrate or channeled features that facilitate the flow of moisture. Flexible and compliant qualities of the liner are such that any embodiment of a liner garment described herein can be donned and everted as described below. A patient donning the liner typically everts the liner, contacts the internal distal-most point of the liner against the distal end of the residual limb, and rolls the liner proximally up the residual limb. Once the initial contact with the residual limb is established, that contact point is maintained as the patient rolls the liner on, converting the everted configuration of the liner into a normal configuration, with the external surface facing outward, and the internal surface facing internally and aligned against the patient&#39;s skin. Materials used for the internal tacky surface of the liner may be informally referred to as “gels”, and such gels may include any appropriate polymer-based material, such as, but not limited to, urethane, silicon, or thermoplastic elastomer. 
         [0057]    Fluid that accumulates in the interfacing space, perspired fluid (“sweat”) is similar in composition to plasma, and substantially aqueous. Perspired fluid is liquid, but it gives rise to water vapor. Movement of perspired fluid thus involves movement of water as a liquid and as vapor. In some embodiments, the socket liners described herein may move liquid water by a fluid transport substrate. One example of a fluid transport substrate is a wicking fabric of material. These are materials that readily absorb moisture and facilitate its movement that directionally favors movement from a wetter area to a dryer area. These substrates may include synthetic fibers, such as, by way on non-limiting examples, may include rayon, orlon, or nylon. Fluid transport substrates may further include natural fibers, such as, by way on non-limiting examples, may include wool, felt, hemp, or cotton. These substrates may include any combination of synthetic and natural fibers, and in any available physical configuration and weight. Movement of water vapor similarly may occur by way of vapor movement from a region of higher partial pressure (as within the interfacing space) to a region of lower partial pressure (as in the environment exterior of the socket). Water vapor movement may occur by way of escape through discrete pores, or by way of exit through a porous material. 
         [0058]    Routes of moisture escape from the interior space to the external environment may be described with reference to the central longitudinal axis of the liner. Fluid movement may occur in a distal direction, a proximal direction, and/or lateral or radial directions from the space within the prosthetic socket to the exterior environment. In another aspect, fluid may move variously across a wettable substrate, through channels, or directly through pores or a porous interface. Further, fluid movement may be passive, being driven only by gravity or by an equilibrium-driven force applied either to liquid or vapor, and/or it may be mechanically assisted. Mechanically assisted fluid movement may include harnessing of force derived from bodily movement of the patient, or by powered pumps, such as electrical pumps. 
         [0059]    In the following description and in the attached figures, a given numerical label may be used to refer to the same component part in different embodiments. For example, a fluid transport portion of a prosthetic liner garment will be shown and described in the context of liner garment embodiments, rather than labeling the different fluid transport portions with distinct numbers. This labeling consistency is used to facilitate understanding of the description and should not be interpreted as suggesting that there is only one embodiment of any given component. Various embodiments of moisture-management liners, prosthetic socket structures that can accommodate such liners, and moisture management devices and methods are described further below, in the context of the drawings. 
         [0060]      FIG. 1  illustrates an embodiment of a prosthetic socket liner garment  10 , including a gel portion  20 , comprising elastomeric material, and a fluid transport or wicking portion  30 . Embodiments of the fluid transport substrate include a wicking material  30  on an internal surface  12  of a prosthetic socket liner  10  to provide a distal-ward flow of moisture (downward-directed arrows) toward a distal fluid exit  40 . In this embodiment, wicking portion  30  is disposed only in a distal portion  18  of the liner garment. As such, a wicking fabric or substrate contacts the residual limb in the distal portion of the liner, while an internal surface of the gel portion  20  of the liner contacts the residual limb within the proximal portion  16  of the liner. In some embodiments, a wicking element may also be incorporated into a distal port  40  in order to facilitate fluid movement. 
         [0061]    Elements that move moisture distally from the distal port are shown in  FIGS. 5-7 , as described further below. The wicking-based movement of moisture depicted in some embodiments is not mechanically assisted, and may be passive to at least some degree, although gravity generally is assistive. The socket liner garment  10  may wick moisture substantially derived from perspiration being released from the skin covering the portion of the residual limb disposed within the prosthetic socket, and the socket liner  10  may also wick other forms of moisture that may accumulate between the patient&#39;s skin and the liner  10 . Forces driving the distal-ward capillary action-based movement of perspired moisture include gravity and a fluid level gradient, wherein there is mass movement of moisture from regions of the wicking material that are heavily laden with water to regions that are drier. 
         [0062]    As shown in  FIG. 1 , in some embodiments, the wicking material  30  is arranged so that its upper or proximal end terminates below the proximal end of the prosthetic socket liner garment  10 , the proximal portion of the liner having only the elastomeric or gel portion  20 . 
         [0063]      FIGS. 2A and 2B  illustrate an embodiment of a socket liner garment  110  similar to that shown in  FIG. 1 , except that the fluid transport substrate or wicking material  30  is arranged into longitudinal strips  30 S distributed circumferentially and spaced apart. From an internal perspective, the internal surface or aspect  12  of the liner garment  110  includes longitudinally aligned zones, the zones comprising alternating gel surfaces and wicking material surfaces, each having its own respective functionalities and advantages. The tacky gel material in the distal region of the liner has sufficient surface area to establish a non-slipping engagement of the moisture management liner against the skin of the distal end of the residual limb. The gel surface further serves to facilitate smooth roll-on donning by virtue of its consistency and pliability. The tackiness of the gel layer further serves to facilitate a stability of the garment on the surface of the skin, generally mitigating against slippage or buckling that could allow air to enter into the space from under the proximal boundary of the liner. The wicking strips serve to move moisture in along a moisture gradient and gravity-driven direction that is generally distal, toward distal fluid exit  40 . 
         [0064]      FIG. 2B  is a distal-looking internal view of the liner garment  110  of  FIG. 2A , where the longitudinally arranged strips of fluid transport substrate or wicking material  30 S taper from a relatively large width at their proximal end to a relatively narrow width at their distal end as they converge centrally and terminate proximal a distal fluid exit  40 . Fluid thus can move distally by way of capillary action, and exit the internal environment within the liner distally. 
         [0065]    In the embodiments shown in  FIGS. 1 ,  2 A, and  2 B, the wicking fabric or fluid transport substrate  30  does not extend proximally to the most proximal edge of the socket liner garments, as in garment embodiments  10  and  110 . Thus, some embodiments of the socket liner garment are arranged such that a wicking material  30  on the interior surface has an upper or proximal edge that terminates at a level below that of the upper or proximal edge of the liner as a whole. In these embodiments, the proximal portion of the gel portion  20  of socket liner garment  10  and  110  thus directly contacts the skin of the residual limb, and can broadly form a seal against the skin that creates a substantially closed environment within the confines of the distal portion of the socket liner garment  10  and  110 . The closed distal environment of these embodiments allows egress of water by way of the distal drain. While the movement of moisture in these depicted embodiments is passive, in other embodiments, moisture can be actively pulled or pushed out through the distal drain. 
         [0066]    In some embodiments, the wicking substrate portion is attachable to, and detachable from, the elastomeric portion of the liner garment. This arrangement is advantageous, in that it allows the liner garment to be embodied in two pieces, a portion that is elastomeric or substantially elastomeric, and a separate wicking piece that can either be rinsed clean and reattached to the elastomeric portion of the liner, or be replaced by a new wicking piece. 
         [0067]      FIG. 3  is a longitudinal cross sectional cutaway view of another alternative embodiment of a prosthetic socket liner garment  210  that is arranged to provide for the escape of water vapor in a lateral or radial direction with respect to the longitudinal axis of the liner. Such escape may occur through pores or ports  22  that may be microscopic or scarcely visible within a fabric, or a generally porous site. (Pores may be generally distinguished from discrete macroscopic formed apertures, such as described further below in the context of  FIG. 5 .) Such pores or ports  22  may be distributed within or on a liner surface comprising a gel. As moisture is brought to the external surface of the gel liner, it has the opportunity to evaporate. Such evaporation, in addition to providing an escape path for moisture, may also advantageously cool the surface of the liner, and such cooling may, in turn, cool the surface of the portion of the residual limb contained within the prosthetic socket. Aside from evaporative cooling, such pores may also provide a path for draining heat from the environment interior to the socket liner. Heat may be drained simply by the conveyance of heat by escaping moisture, which has been heated by the body. 
         [0068]      FIG. 4  shows a longitudinal cross sectional cutaway view of a prosthetic socket liner garment embodiment  310  that is arranged to provide both for distal movement of moisture (as shown in  FIGS. 1-2B ) and for lateral or radial escape of moisture (as shown in  FIG. 3 ). Description of these aspects of the embodiments in the context of those referenced figures applies to the embodiment  310 . The fluid transport portion  30  of this embodiment is disposed both internally and externally with respect to elastomeric portion  20 . The internally arranged fluid transport portion is labeled  30 S to indicate it being arranged as longitudinal strips. Fluid transport substrate or wicking material  30 S is arranged into longitudinal strips on the internal surface  12  of the distal portion  18  of liner garment  310 , and the strips are distributed circumferentially and spaced apart. The internal surface  12  of proximal portion  16  of liner garment  310  includes a region that has pores  22  or perforations that extend through to external surface  14 . The most proximal region of internal surface  12  has no pores, the uninterrupted elastomeric surface being optimal for forming a sealing engagement against a residual limb. 
         [0069]      FIG. 5  is a longitudinal cross-sectional view of a prosthetic socket moisture management liner  410  that has a fluid transport portion  34  in the form of a fabric having mesh pattern of macroscopic apertures or perforations in distal portion  18  of the garment. The fluid transport portion  34  of this particular embodiment comprises a three-dimensional knit or woven structure that provides breathability by way of macroscopic apertures  35  formed by the knit or weave. At least the internal surface  12  of the proximal portion  16  of the liner garment  410  includes a gel or elastomeric portion  20  that provides a tacky surface that provides a sealing contact with the skin of the residual limb. In this particular liner garment embodiment  410 , the elastomeric portion does not necessarily extend into the distal portion  18  of the liner. The thickness or weight of the yarn or fiber used in the knit or weave of mesh can vary, and there is a general correlation between fiber thickness and the size of the apertures of the mesh. In some embodiments, the apertures are formed only by the space between fibers. In other embodiments, the apertures are larger formed structures within the fabric. 
         [0070]    The fibers within the mesh can vary in composition. For example, at least some fibers may be coated with a composition that provides a tackiness that encourages adherence to the skin; at least some fibers may be particularly suitable for supporting capillary movement of moisture; and at least some fibers may be elastic to encourage a close and conformal fit to the residual limb. The apertures in the mesh may large enough to provide direct ventilation through the mesh, moisture as a liquid or vapor moving freely through the mesh. The fibers of the mesh may support wicking from inside the garment to the exterior, whereupon the moisture can evaporate. In some embodiments, the apertures may include structural features that bias net moisture flow in the internal to external direction, in a one-way valve like manner. 
         [0071]      FIG. 6  shows a longitudinal cross sectional cutaway view of a prosthetic socket liner garment embodiment  10  that is arranged to provide a mechanically-assisted removal of moisture from within the interfacing space between the patient&#39;s skin and the surrounding socket. In this particular embodiment, the upper or proximal-most edge of a wicking substrate within the moisture management liner terminates at a level below the upper or proximal-most edge of the liner garment  10  as a whole. In the zone of the liner proximal to the proximal to the wicking fabric or substrate, the liner comes directly in contact with the skin of the patient&#39;s residual limb. Inasmuch as the internal liner surface exposed to the skin is tacky, it tends to form a seal against the skin, and accordingly, the interfacing space between the liner and the skin may be understood as a closed environment. The route of escape for accumulated moisture is by way of a drain at the distal end of the liner. 
         [0072]    This embodiment of the liner is situated within a distal portion of the prosthetic socket structure  5  that includes an annular locking mechanism  52  that secures the socket and liner together by clamping around the drain or associated structure. This connection, in a larger functional sense, provides a prosthetic socket suspension mechanism that prevents the socket from slipping off the residual limb: the gel liner hangs on to the residual limb, the gel liner and distal prosthetic socket structure are locked together, and distal prosthetic components are connected to the distal prosthetic socket structure. Aspects of the suspension mechanism include both a vacuum that is in place and prevents expansion of the interfacing space by the vacuum pressure, as well as by the locking mechanism itself. 
         [0073]    The distally projecting drain  42  leads into a reservoir  60  disposed proximate the distal base such that fluid flows from the interfacing space, through the drain, and into the reservoir, which, itself has a controllable effluent opening, such as a one-way valve  65  that allows one-way efflux of accumulated moisture. 
         [0074]      FIG. 7  is a longitudinal cross sectional cutaway view of a distal portion of prosthetic socket moisture management liner embodiment  10  situated within a socket embodiment that is similar to that depicted in  FIG. 6 . Although liner garment  10  is used in  FIGS. 6-8C , any liner embodiment having a distal drain may be fitted with a reservoir  60 . Whereas the embodiment shown in  FIG. 6  may be considered a passive moisture management approach, driven by gravity and gradient dynamics, the embodiment shown in  FIG. 7  provides an active or powered moisture management approach, as driven by an electric pump  70  that actively withdraws fluid from the reservoir disposed at the base of the socket. 
         [0075]      FIGS. 8A-8C  are longitudinal cross sectional cutaway views of a distal portion of prosthetic socket liner embodiment  10  situated within a socket embodiment that is similar to that depicted in  FIG. 6 , but having a reservoir  72  that acts as pumping mechanism driven by patient movement, rather than electrical power.  FIG. 8A  shows pumping reservoir with fluid exit through outlet  64 , as controlled by a one-way valve  65 . The lower surface or plate  74  of pumping reservoir  72  is resiliently deflectable from a resting position to a deflected position. This deflectable feature is but one example of an inwardly movable portion, which upon application of external pressure, deflects inward, reducing the volume of the reservoir. Movement of the patient, as in walking or shifting body weight, provides the episodic force for such inward movement.  FIG. 8B  shows such an inward deflection of resilient plate  74 , and the consequent reduction in volume or increase in pressure that drives fluid through the one-way valve  65 , thus exiting the reservoir  72 . Upon release of the patient-applied pressure, the lower plate of pumping reservoir  72  resiliently returns to its resting position. In returning to its resting position, either completely or partially, the resting volume of the reservoir  60  is restored toward normal, but the pressure within the reservoir  60  is lowered. Such lowered pressure, as seen in  FIG. 8C , exerts a vacuum pull on the liquid proximal to the drain connecting the skin-liner interfacing space to the reservoir  72 . 
         [0076]    The optional mechanically assisted aspect of moisture flow mechanism is similar to the embodiment shown in  FIGS. 8A-8C , insofar as the patient provides the mechanical force. This embodiment harnesses patient movement as it occurs within the socket, particularly as transmitted against the wall of the socket, rather than the weight bearing distal end. With each step or movement made by the patient, there can be a change in the laterally directed pressure against the wall. Regions of relatively high pressure, which may exist only transiently, will force perspired fluid into the relatively low-pressure zone occupied by the wicking layer. Once in the wicking layer, fluid will be driven distally by gravity. In some embodiments, the wicking layer may include valves, such as deflectable flaps, that preferentially drive liquid in a distal direction, thereby taking further advantage of mechanical force provided by patient movement. 
         [0077]    In particular embodiments of the moisture management technology, the reservoir can achieve and maintain a subatmospheric pressure when being evacuated by the pump. In these embodiments, the subatmospheric pressure of the reservoir, being in communication with fluid (any of air, liquid water, and water vapor) residing in an interfacing layer disposed between the residual limb and the liner, can draw the fluid in from the layer, thereby creating a subatmospheric pressure between the liner and the residual limb. The interfacing layer typically contains a very small volume that can be taken to subatmospheric pressure. One source of such volume may be a fluid transport substrate layer, itself, as associated with the liner or effectively included within the fluid space. Some embodiments of a fluid transport substrate can be compressible and resilient, in which case subatmospheric pressure would cause compression of the fluid transport substrate. 
         [0078]    In some of these particular embodiments, the subatmospheric pressure created within the layer between the residual limb and the liner contributes to the stability or maintenance of the liner on the residual limb. In some of these particular embodiments, the garment liner may be physically connected to the prosthetic socket, and the subatmospheric pressure within the interfacing layer may contribute to maintaining the socket on the residual limb, a capacity generally known as “suspending” the prosthetic socket. In this context, “suspending” refers to holding the prosthetic socket onto the residual limb such that it does not passively or inadvertently slip off. 
         [0079]      FIGS. 9A and 9B  are longitudinal and radial cross sectional views, respectively, of an embodiment of a prosthetic socket liner garment  510  with a layer of fluid transport substrate or wicking material in the form of a channel or layer  30 C sandwiched between internal and external gel or elastomeric layers  20 . The inner elastomeric layer  20  includes an array of pores  22  that provide fluid access to fluid transport substrate embodiment  30 C. The overall form of liner garment  510  is the same as seen in  FIGS. 1-5 , variously depicting other embodiments  10 ,  110 ,  210 ,  310 , and  410 , each having different arrangements of elastomeric portion and fluid transport substrate. 
         [0080]    In liner garment  510 , the fluid transport substrate and elastomeric portion  20  cooperate to form a fluid transport or wicking channel  30 C. The liner garment  510  is shown as being worn by a patient and his or her residual limb  90 . An interfacing layer or space  101  is located between the skin of residual limb  90  and internal surface  12  of liner garment  510 .  FIG. 9A  shows a longitudinal cross sectional cutaway view of a side portion of a prosthetic socket moisture management liner embodiment situated within a socket embodiment;  FIG. 9B  shows an end-on/cross-sectional view. This particular embodiment includes aspects of both passive moisture flow in a distal direction and an optional mechanically assisted flow, as shown in  FIGS. 7-8C . The moisture management liner embodiment  510  depicted here includes one of more fluid transport channels  30 C. The channel is shown disposed between the inner and outer gel layers  20  (on the left) and the skin surface of patient&#39;s residual limb  90  on the right. At spaced apart locations, the internal surface of gel layer has pore openings  22  that allow fluid transport channel  30 C to contact the patient&#39;s skin or interfacing space  101  directly. These openings  22  represent pores or ports through which perspired fluid can flow into the main body of the fluid transport layer  30 C. 
         [0081]    The fluid transport channel  30 C does not need to be circumferentially continuous. In some embodiments (not shown), inner and outer gel layers  20  may converge into a single layer, without an intervening fluid transport layer  30 C. Accordingly, in some embodiments of moisture management liner garment  510 , the fluid transport layer may have a longitudinal strip configuration similar to that of embodiment  110  ( FIG. 2A ), albeit sandwiched between gel layers  20 . 
         [0082]      FIG. 10  shows a prosthetic liner garment embodiment  10  disposed in a prosthetic socket device or framework. A prosthetic socket is not shown in its entirety in  FIG. 10 , but it is represented by prosthetic socket struts  5  and a distal prosthetic structure  50 , both of which may serve as support elements of the moisture management system provided herein. These prosthetic socket components are consistent with modular prosthetic socket embodiments as described in US Published App. No. 2013/0123940 and U.S. patent application Ser. No. 14/213,788 Annular locking mechanism  52  can be supported by any suitable support element in the proximal region of the prosthetic socket, such as a strut, a distal base, or a distal cup. Such detail is omitted from drawing for the sake of clarity. Although the prosthetic liner garment  10  is shown securely disposed within a modular prosthetic socket, as referenced, many available prosthetic sockets are perfectly appropriate for hosting moisture management liner garments, as disclosed herein. 
         [0083]      FIGS. 11A-11B  are schematic representations (not drawn to scale) of cross-sectional views through (progressing outward from the center) a residual limb  90 , a space  101 , a moisture management liner  10 . 1 , a space  102 , and a prosthetic socket  5 . Moisture management liner  10 . 1  is intended to represent any moisture management liner embodiment as described herein. The focus of  FIGS. 11A and 11B  is not directed to any particular aspects of a moisture management liner  10 . 1 , but rather to identify and distinguish spaces  101  and  102 . Space  101  is disposed between the residual limb and the moisture management liner; space  102  is disposed between the moisture management liner and the prosthetic socket. Neither space  101  nor space  102  is an open void; typically these spaces are collapsed or flattened, but they are both sites where fluid may accumulate or be trapped. In general, it is advantageous for the patient, and for the function of both the prosthetic liner and for the prosthetic socket, that fluid (liquid or gas) be minimally present in these spaces. 
         [0084]    Prosthetic socket  5  is intended to represent any prosthetic socket; sockets vary in form, and can vary in their cross sectional profile depending on where the cross sectional view is taken between the proximal and distal ends. Accordingly,  FIG. 11A  depicts a prosthetic socket (or a longitudinal region thereof) wherein the socket structure is circumferentially complete or contiguous.  FIG. 11B  depicts a prosthetic socket (or longitudinal region thereof) where the prosthetic socket is circumferentially segmented or discontinuous. Examples of a prosthetic socket such as that depicted in  FIG. 11B  include modular, strut-based prosthetic sockets as disclosed in US Published App. No. 2013/0123940 and U.S. patent application Ser. No. 14/213,788. 
         [0085]    Prosthetic moisture management liner  10 . 1 , as shown in  FIG. 11A  has an internal surface  12  and an external surface  14 . Prosthetic moisture management liner  10 . 1 , as shown in  FIG. 11B  has an internal surface  12 , and an external surface that can be separated into regions  14 A and  14 B. The actual surfaces may identical but the environments they face are different. Surface region  14 A is directly exposed to ambient air. Surface region  14 B is exposed to an inner aspect of strut or strut segment  5 , and accordingly, contained within space  102  (between the liner and the socket). Radial movement of moisture through garment liner  10 . 1  across surface  14 A allows moisture to escape directly into the environment, while radial movement of moisture through liner garment  10 . 1  across surface  14 S would leave it accumulating within space  102 . 
         [0086]    Space  101 , between a residual limb and a prosthetic socket liner, is the site into which sweat from a residual limb can accumulate. Removal of moisture from this site ( 101 ) is advantageous for the integrity of the skin and underlying tissue of the residual limb, as well as general comfort and fit. Accumulation of moisture in this space can allow slippage of the liner on the limb, which both damages the skin and degrades comfort and fit. Removal of moisture from space  102  is also important, particularly for the grasp of the socket on the liner. “Suspension” of the socket refers broadly to the maintenance of the socket on the limb; the suspension involves secure maintenance of the socket on the liner, and secure maintenance of the liner on the limb. Further aspects of fluid removal from spaces  101  and  102  and described below, in the context of  FIGS. 12-14 . 
         [0087]      FIG. 12  shows a longitudinal cross sectional view of an embodiment of a prosthetic socket, as represented by socket strut  5 , with a liner garment embodiment  310  disposed therein. Liner garment  310  is described above in the context of  FIG. 4 . Briefly, fluid transport substrate  30  is arranged external to elastomeric portion  20 , and fluid transport substrate  30 S is arranged in strips internal to elastomeric portion  20 . The cross-sectional profile includes the fluid transport strips  30 S on both the left and right sides of the image; the intervening spaces between fluid transport strips  30 S is not shown; and the pores  22 , as shown in  FIG. 4  are also not shown.  FIG. 12  also shows an interfacing space  101  disposed between the surface of a residual limb  90  and the internal surface of liner  310 , and an interfacing space  102  between liner  310  and strut  5  of a prosthetic socket. (These interfacing spaces are also shown in  FIGS. 11A-11B .) Distal prosthetic socket structure  50  of prosthetic socket  2  has an annular locking mechanism  52  disposed around distally projecting drain  42  of liner  10 . Annular locking mechanism  52  has a lock release mechanism  54 , which may be operated either manually and/or automatically. “Annular locking” generally refers to a mechanism that is arranged in ring-like or circumferential manner which locks by an inward or centrally directed force. Distally projecting drain  42  enters reservoir  60 , which includes reservoir outlet  64 . A distal prosthetic element connecter  66  is disposed at the distal end of distal prosthetic structure  50 . 
         [0088]    Pump  70  is in fluid connection with reservoir  60 . Vacuum, as drawn in reservoir  60  by the action of pump  70 , draws fluid from the reservoir, which receives fluid drained both from the fluid transporting or wicking portion  30  of liner  10  as well as from an interfacing space  101  that is disposed between the skin surface of residual limb  90  and liner  10 . In one aspect, it may be understood that the fluid transporting portion  30 , by virtue of being generally porous, is itself included in the interfacing space between the limb and a substantially impervious elastomeric portion (not shown) of liner  10 . 
         [0089]    By the pumping action of pump  70  the pressure within reservoir  60  can be dropped to a subatmospheric level. This subatmospheric pressure can be extended into interfacing space  101 , inasmuch as that space is in fluid communication with the reservoir. The atmospheric pressure impinging on the external surface of the liner presses the liner against the skin, creating an adherence and resistance to slippage. This effect contributes to a stability of the liner on the skin surface, in effect, a contribution to suspending the liner on the skin. In some embodiments of the technology, the liner is physically connected to the prosthetic socket structure. Thus, the drawing of vacuum by the pump, ultimately contributes to the suspension of the prosthetic socket on the residual limb. 
         [0090]      FIGS. 13-14  are diagrams depicting embodiments of methods of transporting fluid, such methods being enabled by embodiments of the moisture management liner as disclosed herein.  FIG. 13  is a flow diagram of a method of removing accumulated moisture from within a prosthetic socket fitted with an embodiment of a prosthetic socket liner with moisture management features. In initial steps, a patient dons (step  1301 ) an embodiment of the moisture management liner in the manner described above. Briefly, donning includes everting the liner garment, contacting it against a distal aspect of the residual limb, and rolling the liner up and around the residual limb, restoring the liner to its normal inside/outside configuration. After donning the liner garment, the patient inserts his or her residual limb into a prosthetic socket (step  1302 ), makes adjustments to the socket to optimize fit and functionality, and goes about his or her daily activities. 
         [0091]    During the course of the day, the residual limb sweats and adds fluid into the space between the residual limb and the liner. Embodiments of the method provide for movement of fluid both distally (step  1303 ) and radially (step  1305 ) from that space. Distal movement of moisture may occur through a wicking fabric or substrate  30 , as described herein, or by way of channeled structures within a fabric or substrate  32 , as described herein. Distal movement is typically by way of capillary action, but may include bulk fluid movement as well. Radial movement refers to movement through a moisture management liner by way of pores  22 , as described herein, and may include participation of capillary movement through a wicking substrate as well. 
         [0092]    Fluid that moves distally within the fluid transport substrate of the liner, and is eventually moved into the external environment (step  1304 ). The flow path to the external environment is typically by way of a distal port  40  in the moisture management liner, a distally projecting drain  42 , and a reservoir  60 . Fluid from the reservoir is ultimately released into the environment, generally by ejection and evaporation. Fluid may also move radially through pores  22  in the liner (step  1306 ), and thence eventually into the external environment, ultimately by evaporation from an external surface of a moisture management liner embodiment. 
         [0093]      FIG. 14  is a flow diagram of a method of removing accumulated moisture from within a prosthetic socket fitted with an embodiment of a prosthetic socket liner with moisture management features. This diagram includes the steps shown in  FIG. 13 , but the scope of the method is larger in that it also includes management of moisture that may accumulate external to prosthetic socket liner, but within the confines of a prosthetic socket. The focus is on fluid flow paths from two potential sites of fluid accumulation. A first site of fluid accumulation is within a space between the skin of the residual limb the liner (space  101  in  FIG. 13 ), and second site is a space between the liner and the prosthetic socket structure (space  102  in  FIG. 13 ). The method steps depicted in  FIG. 14  occur after the liner garment has been donned and the patient has inserted his or her residual limb in a prosthetic socket (steps  1301  and  1302 , as depicted in  FIG. 13 ). 
         [0094]    The term “fluid” may refer to any of moisture in liquid form as water, moisture as water vapor, or air. Typically, the fluid in space  101  (between the residual limb and the liner garment) is water in liquid form, although some portion of it may be in vapor form. Generally air from the ambient environment is excluded from the space by the sealing contact between the gel portion of the liner garment at its proximal end and the skin surface of the residual limb, however it may accumulate nevertheless. With these various considerations noted, fluid within space  101  can be moved radially (step  1401 ) or distally (step  1403 ). Fluid moved radially (step  1401 ) is then moved (step  1202 ) into an environment external to the liner garment, as described above in context of  FIG. 13 . 
         [0095]    Depending on the structure of the prosthetic socket in which the liner garment is disposed and the relative position of the liner within the socket, fluid passing radially (Step  1401 ) from space  101  can move directly into the external environment (step  1402 ), or, alternatively it could still be trapped internally within the socket, and therefore contribute to fluid in space  102 . The line that connects step  1401  to fluid space  102  represents a pathway that follows from this alternative eventuality. Once the fluid is in space  102 , it can move distally, as shown, by way of steps  1404 ,  1405 , and  1406 . 
         [0096]    Fluid from both spaces  101  (between the skin and the liner garment) and  102  (between the liner garment and the socket) can move distally (independently). Fluid moving distally from space  101  (step  1403 ) and distally from space  102  (step  1404 ) converges into a common pool, and moves into a reservoir (step  1405 ). From the reservoir, fluid is released into the external environment (step  1406 ). 
         [0097]    Any one or more features of any embodiment of the invention, device or method, can be combined with any one or more other features of any other embodiment of the invention, without departing from the scope of the invention. It should also be understood that the invention is not limited to the embodiments that are described or depicted herein for purposes of exemplification, but is to be defined only by a fair reading of claims appended to the patent application, including the full range of equivalency to which each element thereof is entitled. Further, while some theoretical considerations have been offered to provide an understanding of the technology (as understood by the inventors) such as, for example, the manner in which moisture flows through fluid transport substrates, the claims to the invention are not bound by such theory.