Patent Description:
<CIT> - which is the closest prior art document and upon which the preamble of claim <NUM> is based - discloses a knee joint comprising a knee cap head, an interlinking device including two arch plates, a buffering device including an interlinking rod, an interlinking support and a hydraulic cylinder; a spring device having a spring and a spring support; and a knee cap body module.

The present invention relates to a modular prosthetic device as set out in the claims.

The chassis assembly can comprise the joint portion, a structural frame, and a mounting portion. The structural frame can accept the interchangeable module, where the interchangeable module can be secured to the chassis assembly via complementary mating slots and tabs on the structural frame and the interchangeable module. The interchangeable module is secured to the joint portion via a locking mechanism, where the locking mechanism is engaged with the joint portion via a lever and locking wedge. The locking mechanism can comprise a top snap configured to engage with the locking wedge to secure the joint portion to the interchangeable module. The top snap can be coupled to a damping mechanism of the interchangeable module. The damping mechanism can be a piston assembly. In various aspects, the chassis assembly can be configured to accept removable prosthetic modules attached to the mounting portion. The interchangeable module can comprise a damper driven mechanism. The modular prosthetic device can be selected from a leg, a lower leg, an arm, and a forearm. The joint portion can be securely attached to an existing osseous implant or existing prosthetic socket.

In one or more aspects, the joint portion can comprise a rotatable mounting plate configured to be secured to an implant or prosthetic socket of a user; and the interchangeable module can comprise a locking mechanism configured to engage an open cavity of the rotatable mounting plate to secure it in a load bearing position. The locking mechanism can comprise a pair of flanges configured to engage with a surface of the open cavity to secure the rotatable mounting plate in the load bearing position. The pair of flanges can tilt inward towards each other to facilitate insertion in the open cavity, and can flex outward to engage with the surface of the open cavity. The rotatable mounting plate can comprise a locking wedge that forces the pair of flanges to flex outward when inserted between the pair of flanges. The rotatable mounting plate can comprise a lever that forces the locking wedge between the pair of flanges when rotated from an extend position to a locked position. In various aspects, the chassis assembly can comprise an anchor on a module mounting surface at a distal end of the chassis assembly, and the interchangeable module can comprise a corresponding recess configured to align with the anchor when the interchangeable module is inserted into the chassis assembly. The interchangeable module and structural frame of the chassis assembly can comprise mounting ridges and mounting grooves configured to secure the interchangeable module in the structural frame.

Further aspects of the present disclosure will be more readily appreciated upon review of the detailed description of its various embodiments, described below, when taken in conjunction with the accompanying drawings.

Before the present disclosure is described in greater detail, it is to be understood that this disclosure is not limited to particular embodiments described, and as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims.

Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the disclosure. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges and are also encompassed within the disclosure, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

Embodiments of the present disclosure will employ, unless otherwise indicated, techniques of mechanical engineering, biomedical engineering, material science, and the like, which are within the skill of the art.

The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how to perform the methods and use the devices disclosed and claimed herein. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.), but some errors and deviations should be accounted for.

Before the embodiments of the present disclosure are described in detail, it is to be understood that, unless otherwise indicated, the present disclosure is not limited to particular materials, configurations, manufacturing processes, or the like, as such can vary - provided that these fall under the scope of protection set out in the claims.

The present disclosure relates to a modular prosthetic device as set out in the claims.

The present disclosure illustrates devices and systems for modular prosthetics that can be used for joints such as knees or elbows. Beginning with <FIG>, shown is an example of a modular prosthetic <NUM> that can be used as a knee joint. <FIG> is a top view, <FIG> is a right side view, <FIG> is a front view, <FIG> is a left side view, <FIG> is a rear view and <FIG> and <FIG> provide perspective views of the prosthetic <NUM>. The prosthetic <NUM> includes a chassis assembly <NUM> which can be coupled to a socket or other attachment device for use by a user. Interchangeable modules <NUM> for specific activities or environments can then be inserted into or attached to the chassis assembly <NUM>. The prosthetic device allows for many levels of customization and can be easily changed by the user to suit his/her needs. Advantageously, the chassis assembly <NUM> is load bearing and can attach at the proximal end to an existing osseous implant or prosthetic socket of the user, eliminating the need for additional surgical procedures or costly new socket fittings. At the distal end, the chassis assembly <NUM> can include a mounting portion <NUM>, which can be customized for the user's height. The mounting portion <NUM> can include a plate and screw adapter that can be modified to attach to a prosthetic attachment such as, but not limited to, artificial hands and feet. In the case of the lower leg example of <FIG>, the prosthetic attachment can include virtually any foot and/or pylon system available. An advantage to this configuration is that the user can incorporate existing foot and pylon configurations (e.g., running blades, skates, skis, cycling feet, etc.) already available on the market, eliminating the need for further customization and maximizing options.

Embodiments of the present disclosure include a custom chassis assembly <NUM> configured to accept interchangeable modules <NUM>. In various embodiments, the prosthetic device <NUM> of the disclosure can be a limb or portion of a limb. In various embodiments, the interchangeable modules <NUM> can be designed to insert inside the chassis assembly <NUM>, and can be secured using fastening mechanisms such as magnets, snaps, tabs, button clips, or other appropriate securing mechanisms.

In various embodiments, the interchangeable modules <NUM> can be configured to aid the user in adapting to the demands of specific activities, terrains, or environments. The interchangeable modules <NUM> can include damping devices, pistons, shock absorption mechanisms, or other types of suspension and control mechanisms. In some implementations, the interchangeable modules can include the ability to attach (e.g., snap, clamp, etc.) other compartments and/or components for specific applications (e.g., military or civilian such as a golf ball holder, etc.) to the module.

In various embodiments, the chassis assembly <NUM> can attach to the user at above-knee level. The chassis assembly <NUM> includes a joint portion <NUM> such as, e.g., a knee portion which can attach to the user's existing interosseous implant or prosthetic socket via an attachment mechanism such as, e.g., a plate. Other attachment mechanisms can be utilized for attaching the joint portion <NUM> directly to the user without a plate using, e.g., torque connectors, transcutaneous connectors, sliding locks, threaded pipes, button clips, and/or collar locks depending upon the type of ossteointegrated implant or socket in use. The joint portion <NUM> can be pivotally affixed to the structural frame of the chassis assembly <NUM> as illustrated in <FIG>. The joint portion <NUM> can also include a mechanism (e.g., a lever and wedge, cam shaft, latch, pin, collar lock or other appropriate securing mechanism) for attaching and locking the interchangeable module into place. In some embodiments, the joint portion <NUM> is fastened to the structural frame of the chassis assembly using shoulder bolts and barrel nuts while not loading the threads of the fasteners in shear. In some embodiments, the chassis assembly <NUM> can be posteriorly convex in shape to mimic the shape of the calf. The module <NUM> can be shaped to conform to the shape of the chassis assembly <NUM>. The module <NUM> can be retained within the open structural frame or can be molded to overlap a portion of the structural members of the chassis assembly <NUM>. The exposed portion at the front of the module <NUM> can mimic the shape of the shin of the leg. In various embodiments, the chassis assembly <NUM> can be made from titanium, polymers, carbon fibers, aluminum, stainless steel, or combinations thereof.

<FIG> provide various views of an example of a modular prosthetic device <NUM> of the disclosure, demonstrating the chassis assembly <NUM> and the interchangeable module <NUM>. In the example shown in <FIG>, the interchangeable module <NUM> is installed in the chassis assembly <NUM> and is shown engaged in the standing position. As can be seen, the structural frame of the chassis assembly <NUM> can be an open framework comprising a combination of structural members such as, e.g., horizontal and vertical structural members (or longitudinal and circumferential structural members). The combination of vertical and horizontal members can be arranged to transfer load forces between the mounting portion <NUM> and the joint portion <NUM>, without exposing the module <NUM> to undue stress. The vertical and horizontal members can be shaped to approximate various body parts, while being able the handle the stresses imposed by use of prosthetic <NUM>. For example, the structural frame can include two vertical side members <NUM> and a vertical central member <NUM> extending between a lower (or distal) mounting base <NUM> and upper (or proximal) attachment fixtures <NUM> for the joint portion <NUM>. The vertical side and central members <NUM> and <NUM> can be curved or shaped to allow for insertion of an interchangeable module <NUM> into the framework.

In the side views of <FIG>, the vertical side members <NUM> extend from the attachment fixtures <NUM> to the mounting base <NUM> on opposite sides of a longitudinal axis of the modular prosthetic <NUM>. As shown in the front view of <FIG>, the vertical side members <NUM> curve outward as they extend between the proximal and distal ends. This can also be seen in the rear view of <FIG>. As illustrated in <FIG>, the central member <NUM> can extend from the mounting base <NUM> towards the joint portion <NUM>. The central member <NUM> can include two arms that separate and extend to the attachment fixtures <NUM> to avoid interference with the joint portion <NUM>. As shown in the side views of <FIG>, the central member <NUM> can bend outward and then curve back inward as the two arms extend toward the attachment fixtures <NUM>. One or more horizontal members <NUM> can extend between the vertical side members <NUM>, and over the central member <NUM> to avoid distortion when pressure is applied to the prosthetic device <NUM>. As can be seen in the example of <FIG>, the shapes of the vertical side members <NUM> and the central member <NUM> mimic the shape of the physical limb and allow sufficient space for the operating mechanisms of the interchangeable modules <NUM>.

At the upper or proximal end, the chassis assembly <NUM> includes the joint portion <NUM>, which is pivotally attached to the structural frame via the attachment fixtures <NUM> to allow for rotational motion of the mounting plate <NUM> (or other attachment mechanism) with respect to the structural frame. In the example of <FIG>, two pivot arms <NUM> extend from the mounting plate <NUM> and fit between the attachment fixtures <NUM>. The location and orientation of the pivot arms <NUM> on the mounting plate <NUM> can be designed to allow for movement that mimics that of a natural joint, while allowing for operation of the installed module <NUM>. The attachment fixtures <NUM> and pivot arms <NUM> include openings or holes that can be aligned to pivotally attach the joint portion to the structural frame. Fasteners such as, e.g., shoulder bolts and barrel nuts can extend through the openings to secure the joint portion <NUM> to the structural frame. In other implementations, the openings in either the attachment fixtures <NUM> or pivot arms <NUM> can be threaded to receive a bolt or screw passing through the opening in the pivot arm <NUM> or attachment fixture <NUM> to movably attach the joint portion <NUM> to the structural frame. The fasteners can be configured to prevent loosening of the connection between the attachment fixtures <NUM> and pivot arms <NUM> to avoid accidental disconnection during use of the prosthetic <NUM>. One or more spacers or bushings can be positioned between the pivot arms <NUM> and attachment fixtures <NUM> (e.g., on the bolt, screw, or other fastener) to facilitate alignment and/or proper clearance. In addition, spacers (e.g., sleeves or bushings made from nylon, PTFE, or other appropriate material) can be included in the openings of the attachment fixture <NUM> and/or pivot arm <NUM> around the fastener to facilitate smooth movement of the pivot point.

In the example of <FIG>, the mounting plate <NUM> is shown with a substantially planar mounting surface for attachment to the socket or implant of the user, however other surface contours can also be provided. As shown in the top view of <FIG>, openings can pass through the mounting plate <NUM> to reduce weight while maintaining structural strength and integrity. The mounting plate <NUM> can include holes and/or openings to allow the joint portion <NUM> to be secured to the socket or implant of the user. In some implementations, an adapter can be affixed to the mounting plate <NUM> to allow the prosthetic <NUM> to be adjust for different socket or implant configurations. The mounting plate <NUM> is configured to attach to the module <NUM> opposite the implant mounting surface as will be discussed.

At the lower or distal end, the chassis assembly <NUM> includes the mounting base <NUM>, to which the mounting portion <NUM> can be attached. As will be discussed, the interchangeable module <NUM> can rest upon the mounting base <NUM> opposite the mounting portion <NUM> when installed in the chassis assembly <NUM>. The mounting base <NUM> includes a base mounting surface configured to secure the mounting portion <NUM> to the mounting base <NUM>. The mounting base <NUM> also includes a module surface opposite the base mounting surface that can receive one end of the interchangeable module <NUM>. The module surface can be substantially planar as illustrated in <FIG>, or can be shaped to match the contour of the end of the module <NUM>. The chassis assembly <NUM> including the mounting base <NUM>, structural frame with vertical and horizontal members, and attachment fixtures <NUM> can be fabricated as a single integral piece with the vertical side and central members <NUM> and <NUM> extending between the mounting base <NUM> and the attachment fixtures <NUM>. In the example of <FIG>, a horizontal member <NUM> extends across an outer edge of the mounting base <NUM> between the two vertical side members <NUM>. For example, the chassis assembly can be cast as a single unit and machined to the desired dimensions for use.

<FIG> shows an example of the modular prosthetic device <NUM> with the chassis assembly <NUM> and the interchangeable module <NUM> in a detached position. An example of the interchangeable module <NUM> is illustrated. As shown, the module <NUM> can include a module casing <NUM> shaped to conform to the inner shape of the chassis assembly <NUM>. The inner surface of the structural frame can also be contoured (e.g., flattened or recessed) to match the outer surface of the module casing <NUM> as shown in <FIG>. The chassis assembly <NUM> can include tabs and/or grooves that can align with corresponding features on the interchangeable modules <NUM> to secure the module <NUM> in place. For example, the mounting base <NUM> can include an anchor (or recess) <NUM> on the module surface which can be aligned with a corresponding recess (or anchor) on the bottom or end of the interchangeable module <NUM>. The vertical side members <NUM> can also include mounting grooves and/or tabs <NUM> that can align with mounting ridges and/or depressions (or tabs and/or grooves) <NUM> on the sides of the module <NUM> to hold the module <NUM> in position. The mounting ridges and/or depressions <NUM> can snap into/onto the mounting grooves and/or tabs <NUM> of the structural frame for secure attachment of the module <NUM>.

Referring to <FIG>, shown are various views of the chassis assembly <NUM> without an interchangeable module <NUM> installed. <FIG> shows a top view, <FIG> shows a front view, <FIG> shows a left side view, and <FIG> shows a perspective view of the chassis assembly <NUM>. As can be seen in <FIG>, the grooves and/or tabs <NUM> align with one of the horizontal members <NUM>. This can provide additional rigidity and strength for securing the interchangeable modules <NUM> in place. In addition, <FIG> illustrates the vertical central member <NUM> with two arms <NUM> that separate and extend to the attachment fixtures <NUM> to avoid interference with the joint portion <NUM>. The shape of the arms <NUM> can be designed to handle the stress and strain placed on the structural frame during use.

Referring back to <FIG>, an example of the interchangeable module <NUM> is illustrated. The module <NUM> includes a locking mechanism <NUM> that engages with the joint portion <NUM> to couple or engage the functionality of the module <NUM> with the chassis assembly <NUM>. <FIG> shows an exploded view of the chassis assembly <NUM> including the joint portion <NUM>, the structural frame <NUM>, and the mounting portion <NUM>. The joint portion <NUM> can include the mounting plate <NUM> (or other attachment mechanism) with two pivot arms <NUM> extending from one end of the mounting plate <NUM>. The pivot arms <NUM> are sized to fit between the attachment fixtures <NUM>, and both include openings or holes that can be aligned with corresponding opening or holes in the attachment fixtures <NUM> to allow the joint portion <NUM> to pivotally attach to the attachment fixtures <NUM> of the structural frame <NUM>. Fasteners such as, e.g., shoulder bolts <NUM> and barrel nuts <NUM> can extend through the openings. Spacers and/or sleeves can be used to ensure proper alignment of the joint portion <NUM>, and can be used to reduce friction. The joint portion <NUM> also includes a lever <NUM> and locking wedge <NUM>, which facilitate coupling of the locking mechanism <NUM> of the interchangeable module <NUM> to the mounting plate <NUM>. The lever <NUM> can be pivotally attached to the mounting plate <NUM> using, e.g., a recessed screw <NUM>, bolt or other appropriate fastener. The lever <NUM> acts as a camshaft that linearly displaces the locking wedge <NUM> into the locking mechanism <NUM> by rotating the lever <NUM> about the screw <NUM>, the tab at the proximal end moves the locking wedge <NUM> forward to engage with the top flap or flanges of the locking mechanism <NUM>, thereby securing the module <NUM> to the joint portion <NUM>.

The chassis assembly <NUM> includes the mounting portion <NUM>, which can be detachably attached to the mounting base <NUM> of the structural frame <NUM> as illustrated in <FIG>. The mounting portion <NUM> can include a mounting adapter <NUM> that can be secured to the mounting base <NUM> via one or more screws (e.g., <NUM> flat head hex drive stainless screws) or other appropriate fasteners <NUM>. The mounting portion <NUM> may also be attached using other appropriate mounting methods such as, e.g., a sliding or rotating lock assembly. For example, a ball lock may be utilized. In various embodiments, the mounting portion <NUM> can be developed by a prosthetist to fit the user. At the distal end of the mounting portion <NUM>, a lock and plate mechanism <NUM> can be fitted to provide a standardized fitting to attach virtually any foot and pylon systems (e.g., footlankle system, sprinting blades, cycling clip foot mounts, inflexible mounts, or elastic keel feet designed for particular activities) available to the user. Other attachment mechanisms can be fitted to accommodate various foot configurations, e.g., torque connectors, transcutaneous connectors, sliding locks, threaded pipes, button clips, and/or collar locks. Hand and/or other attachments may also be utilized for arm prosthetics.

Referring next to <FIG>, shown is an example of an interchangeable module <NUM>. The interchangeable module <NUM> can take various forms (e.g., damper driven, robotic, computer controlled, etc.). For instance, shock/piston, EVA (e.g., rubber and/or polymer), microprocessor units (MPUs) or other components can be included in the interchangeable modules <NUM> to create a specialized unit or module to provide a specific result in applied applications.

In <FIG>, an example of a damper driven module <NUM> is illustrated. In various embodiments, the damper can be, e.g., hydraulic, pneumatic, electromagnetic, spring, etc. In various embodiments, the interchangeable module <NUM> can include a module casing <NUM>, a locking mechanism <NUM>, and a pivot point (or recess) <NUM> (<FIG>), which can be incorporated into the module casing <NUM>. The locking mechanism <NUM> can include a top snap or flanges <NUM>, which engage with the locking wedge <NUM> (<FIG>) affixed to the mounting plate <NUM>. The top snap can be configured to secure the interchangeable module <NUM> into the chassis assembly <NUM>. As shown in <FIG>, the top snap of the locking mechanism <NUM> includes opposing flanges <NUM> that are angled inward toward each other. The flanges <NUM> are flexibly connected to the end of the module casing <NUM> opposite the pivot point <NUM>. The connection allows the flanges <NUM> to flex outward, away from each other to engage with the mounting plate <NUM>. In various embodiments, the interchangeable module <NUM> can be made from titanium, polymers, carbon fibers, aluminum, stainless steel, or combinations thereof.

<FIG> illustrate a cross-sectional view of the damper driven module <NUM>. The module casing <NUM> can enclose the interior mechanisms, such as the damper assembly <NUM> in an internal void <NUM>. As shown in <FIG>, the cross-section (A-A) is taken along the centerline of the module <NUM> from the front side to the rear side between the two flanges <NUM> of the locking mechanism <NUM>. The cross-sectional view A-A is presented in <FIG>. In the example of <FIG>, the damper assembly <NUM> comprises a piston in a cylinder <NUM>. Movement of the piston in the cylinder <NUM> is dampened by the fluid (e.g., oil, water, air or other suitable hydraulic or pneumatic fluid) in the cylinder <NUM>. The amount of damping provided by the damper assembly <NUM> can be affected by the viscosity of the fluid, size of the cylinder <NUM>, size of the piston, clearance between the piston and cylinder wall, or other appropriate design variable. The damping assembly <NUM> is connected to the locking mechanism <NUM> by a piston rod <NUM> that passes through an opening <NUM> in the module casing <NUM>. The connection between the piston rod <NUM> and locking mechanism <NUM> is configured to rotate (e.g., about a connecting pin). As shown in the enlarged view of <FIG>, the top snap is connected to the module casing <NUM> at one end, while the other end is coupled to the piston rod <NUM> to a surface of the top snap opposite the flanges <NUM>. For example, tabs can extend on both sides of the piston rod <NUM> with a connection pin extending through both the tabs and the piston rod. As the top snap moves about the connection point, the movement is transmitted to the piston, which moves within the cylinder <NUM>. Such movement can dampen the effect of force applied to the mount plate <NUM> by the user. The opposite end of the cylinder <NUM> is also configured to rotate about a connection pin or shaft, which can extend across the module casing <NUM> through the internal void <NUM>. This rotation can maintain alignment of the piston rod <NUM> in the damper assembly <NUM> as the top snap moves about the connection to the module casing <NUM>.

<FIG> illustrate another cross-sectional view of the damper driven module <NUM>. As shown in <FIG>, the cross-section (F-F) is perpendicular to cross-section A-A of <FIG> and extends across the module <NUM> from the left side to the right side and passes through the flanges <NUM>. The cross-sectional view F-F is presented in <FIG>, which shows the internal void <NUM> of the module casing <NUM> and a portion of the cylinder <NUM> of the damper assembly <NUM>. Detail AC illustrates the relationship of the top snap or flanges <NUM> of the locking mechanism <NUM> and detail C shows the positioning of the top snap or flanges <NUM> on the module casing <NUM>. As seen in detail AC, narrow sections are provided at the lower corners of the flanges <NUM> to allow for flexing and outward movement. Detail C shows a side view of the flexible connection with the module case <NUM>. Magnetic ball, snap fit, or likewise can be used.

In various embodiments, the user can easily secure the interchangeable module <NUM> into the chassis assembly <NUM> without assistance. 8A-13C illustrate an example of the process of installing the interchangeable module <NUM> into the chassis assembly <NUM>. In <FIG>, the modular prosthetic <NUM> has been illustrated with the joint portion <NUM> in a standing position where the prosthetic would be load bearing with the mounting plate <NUM> substantially perpendicular to a longitudinal axis of the chassis assembly <NUM>. To insert an interchangeable module <NUM>, the user assumes a non-load bearing position (e.g., sitting), and loosens the lever <NUM> (e.g., rotating it outward) on the joint portion <NUM> of the chassis assembly <NUM>, allowing the joint portion <NUM> to pivot into an open position as illustrated in <FIG>. In this position, the mounting plate <NUM> can be positioned substantially parallel with the longitudinal axis of the chassis assembly <NUM> as shown in <FIG> is a front view of the interchangeable module <NUM> being aligned with the anchor <NUM> of the chassis assembly <NUM>. The lever <NUM> is shown rotated outward thereby allowing the locking wedge <NUM> to move to a retracted position. The cross-section G-G passing along the longitudinal axis, from front to rear, is shown In <FIG>. The interchangeable module <NUM> can be inserted at an angle into the chassis assembly <NUM> with the anchor <NUM> on the mounting base <NUM> aligned with the pivot point (or recess) <NUM> on the bottom of the module casing <NUM> as shown in <FIG>. This alignment between the anchor <NUM> and recess <NUM> is enlarged in detail AD. The corner of the module casing <NUM> can rest on the surface of the mounting base <NUM> as shown in <FIG> while positioning the pivot point <NUM> on the anchor <NUM>.

The module <NUM> can then be rotated about the pivot point <NUM> and anchor <NUM> into the structural frame <NUM>. As the interchangeable module <NUM> rotates about the anchor <NUM> and moves into the structural frame <NUM>, the mounting ridges (or tabs) <NUM> on the sides of the module <NUM> contact the mounting grooves (or slots) <NUM> in the vertical side members <NUM> of the structural frame as illustrated in <FIG>. Detail F is an enlarged view illustrating the engagement of the mounting ridges (or tabs) <NUM> with the mounting grooves (or slots) <NUM>. The cross-section D-D passing through one of the vertical side members <NUM> of the structural frame <NUM> is shown in <FIG>, where the mounting ridge (or tab) <NUM> is in contact with the vertical side member <NUM> prior to insertion into the mounting groove (or slot) <NUM>. This is enlarged in detail E of <FIG>. Applying sufficient pressure to the front of the interchangeable module <NUM>, the mounting ridges (or tabs) <NUM> can be inserted into the corresponding mounting grooves (or slots) <NUM>. As can be appreciated, the vertical side members <NUM> of the structural frame can include mounting ridges (or tabs) and the module casing <NUM> can include mounting grooves (or slots) to provide the engagement.

A snap fit can be achieved upon insertion of the interchangeable module <NUM> into the chassis assembly <NUM>, providing an easy but secure assembly, as shown in <FIG>. The cross-section G-G of <FIG> passes through the same vertical side member <NUM> as in <FIG>. As is shown in <FIG>, the mounting ridge (or tab) <NUM> is snapped into the mounting groove (or slot) <NUM>. This is enlarged in detail H of <FIG> shows the interchangeable module <NUM> secured in the structural frame <NUM> by the mounting ridges <NUM> in the mounting grooves <NUM>. Application of force on the rear of the module <NUM>, through the structural frame <NUM>, can unsnap the interchangeable module <NUM> from the chassis assembly <NUM>. <FIG> show front, side and perspective views of the chassis assembly <NUM> with the interchangeable module <NUM> snapped in position and the mounting portion <NUM> attached to the mounting base <NUM>.

With the interchangeable module <NUM> snapped into position, the user can stand up (or extend the leg) pivoting the joint portion <NUM> forward as illustrated in <FIG>. In this position, the mounting plate <NUM> is in a load bearing position substantially perpendicular to the longitudinal axis of the chassis assembly <NUM>. This motion will position the top snap of the locking mechanism <NUM> in line with the locking wedge <NUM> of the joint portion <NUM>, as shown in the example in <FIG>. The cross-sectional view K-K of <FIG> is presented in <FIG>, which shows the internal void <NUM> of the module casing <NUM> and a portion of the cylinder <NUM> of the damper assembly <NUM>. Detail L shows an enlarged horizontal view of the locking wedge <NUM> aligned with the top snap or flanges <NUM> of the locking mechanism <NUM>. <FIG> shows the cross-section S-S of <FIG>, with detail T providing an enlarged vertical view of the locking wedge <NUM> aligned with the top snap or flanges <NUM> of the locking mechanism <NUM>. As shown in details L and T, with the mounting plate <NUM> rotated into position, the top snap or flanges <NUM> are located within an open cavity <NUM> of the mounting plate <NUM>. With the lever <NUM> extending outward as shown in <FIG>, the distal end of the locking wedge <NUM> is adjacent to one end of the gap between the flanges <NUM>. As can be seen in detail L, the inward tilt of the flanges <NUM> allow the top snap to easily align with the cavity <NUM> in the mounting plate <NUM>. The pre-bent snap fit allows for a relatively minimal insertion and removal force.

Next, as shown in <FIG>, the lever <NUM> can be rotated flush with the front of the mounting plate <NUM>. As the lever <NUM> is rotated about <NUM> degrees, the short tab presses against the end of the locking wedge <NUM>. The lever action of this motion linearly displaces the locking wedge <NUM> into the top snap of the locking mechanism <NUM>, spreading the flanges <NUM> of the top snap as the locking wedge <NUM> is forced between them. As the arms expand, they are forced apart enough to encompass the entire cavity <NUM> in the mounting plate <NUM>. <FIG> shows the cross-sectional view M-M and <FIG> shows the cross-sectional view N-N indicated in <FIG>. As shown in details O and P, the top snap or flanges <NUM> are forced apart and engage with the outer surface of the cavity <NUM>. With the locking wedge <NUM> inserted between the ends of the flanges <NUM>, the flanges <NUM> can provide a friction fit with the sides of the open cavity <NUM> thereby locking the mounting plate <NUM> to the module <NUM>. When the top snap or flanges <NUM> is fully installed and locked, the joint portion <NUM> locks in the XYZ coordinates, as shown in <FIG>. The cross-section Y-Y, and the enlarged detail Z, illustrates the positioning of the top snap or flanges <NUM> of the locking mechanism <NUM> with the lever <NUM> in the locked position with the locking wedge <NUM> secured between the flanges <NUM>.

Claim 1:
A modular prosthetic device, comprising:
a chassis assembly (<NUM>) comprising a joint portion (<NUM>), a structural frame (<NUM>), and a mounting portion (<NUM>); and
an interchangeable module (<NUM>) configured to be removably attached to the chassis assembly, wherein the interchangeable module is secured to the joint portion via a locking mechanism (<NUM>, <NUM>) of the interchangeable module, wherein the locking mechanism is engaged with the joint portion characterised in that the locking mechanism is engaged with the joint via a lever (<NUM>) and locking wedge (<NUM>).