Leg and foot support assembly for medical examination table

A medical examination table having a leg and foot support assembly that may be pivoted between a raised position, where it is generally coplanar with the seat section of the table, and any of a variety of lowered positions. The assembly includes a frame pivotally connected to the seat section and a footrest extension which is capable not only of being extended and retracted in the general plane of the frame but also of being pivoted into foot-supporting positions disposed at substantially right angles to the frame. Such adjustments are accomplished without the need for attaching or detaching any components of the assembly. Should the assembly be in a generally vertical position and engage an obstruction as the table is lowered (as where the table is equipped with a power drive for raising and lowering), the support assembly will retract automatically to avoid injury that might otherwise result.

BACKGROUND 
Retractable footrests for various types of chairs and examination tables 
are well known in the art but such structures are usually incapable of the 
wide variety of adjustments necessary for medical usage, are often 
difficult or time consuming to adjust properly, and sometimes require the 
detachment or attachment of components or accessories to achieve the 
desired condition for a selected medical procedure. The result, in 
general, is that if adequate adjustment is even possible, such adjustment 
cannot always be performed quickly and without attaching or detaching 
various components. Such shortcomings may have serious consequences in 
medical procedures where speed and reliability are generally considered 
essential. 
U.S. Pat. No. 4,168,099 discloses a multi-position power-operated 
examination chair with leg-supporting cradle elements but without 
associated footrest structures. Other patents disclosing chairs and tables 
equipped with legrests and/or footrests, whether for medical or 
non-medical use, are U.S. Pat. Nos. 3,100,129, 3,869,169, 3,151,910, and 
9,960. 
SUMMARY OF THE INVENTION 
The leg and foot supporting assembly of this invention is particularly 
suitable for use as part of a power-operated medical examination table 
capable of being raised and lowered electrically or hydraulically, and 
preferably one that also has power means for pivoting the leg and foot 
support assembly between a raised position in which that assembly is 
generally coplanar with the seat section of the table (as commonly 
required during basic patient examination, colonoscopic examination, 
endoscopic examination, pediatric examination, Trendelenburg and reverse 
Trendelenburg orientation, etc.), and a lowered position in which the 
support assembly extends downwardly at generally right angles to the seat 
section (as may be required for gynecological examination, urological 
procedures, proctoscopic examination, etc.). Such an assembly may also be 
power operated into any of an infinite number of partially lowered 
positions to suit the requirements of a medical procedure or to meet the 
needs or preferences of the patient. 
The leg and foot support assembly is composed of two main parts that may be 
horizontally extended and retracted to provide proper support for patients 
of different sizes and shapes. Such adjustment may be easily and quickly 
accomplished manually without tools and without adding or removing one or 
more related components. When the assembly is swung into a lowered 
position, one of the parts of that assembly, termed a footrest extension, 
may be pivoted into a position at generally right angles to the other part 
and shifted into any of a variety of selected elevations to provide an 
effective footrest for the patient. Again, such adjustments may be easily 
and quickly performed without tools and without adding (or removing) 
components, adjusting levers or handles, removing or connecting springs or 
pins, or manipulating any small parts that might become jammed or 
detached. 
A feature of particular importance in view of the power operation of the 
table/chair is the ability of the leg and foot support assembly to 
collapse or retract automatically should the assembly engage an 
obstruction as the table/chair as a whole is being power driven into a 
lowered position. Such automatic retraction avoids or at least minimizes 
the damage that might be caused to other medical equipment and furniture 
engaged by the leg support assembly as the power-driven table descends, 
and could prevent serious injury to a doctor, nurse, or assistant who 
happens to have a foot, limb, or other body part in the way of the support 
assembly during such a lowering operation. 
Since there are no handles or levers requiring manipulation when the leg 
and foot support assembly is to be adjusted and set at a selected 
position, both hands may be used to grasp the assembly and carry out the 
action needed for proper adjustment. Such adjustments may be easily made 
by one person with a minimum of effort and time. 
Briefly, the leg and foot support assembly includes a frame which is 
hingedly connected at its proximal end to the seat section of an 
examination table/chair for power-operated movement between raised and 
lowered positions. The frame includes at least one vertical and 
longitudinally-extending wall, and preferably a pair of such walls in the 
form of spaced parallel side walls, having first and second longitudinal 
guide rails that define an elongated guide slot between them. The second 
main component of the assembly, the footrest extension, has an elongated 
side member that extends along each such longitudinal wall of the frame. 
Each side member of the footrest extension has a pair of bearing elements 
adjacent the proximal end thereof, one of the elements being slidably 
retained in the guide slot for both slidable and pivotal engagement with 
the inwardly facing longitudinal surfaces of the rails defining that slot. 
The other bearing element of each side member is slidably engagable with 
the outwardly facing surfaces of the guide rails. Stop means closes off 
the guide slot at its proximal end, thereby limiting sliding movement of 
the one bearing element in a proximal direction while at the same time 
permitting pivotal movement of the footrest extension for the purpose of 
shifting the second bearing element from sliding engagement with the 
outwardly facing surface of one of the guide rails into sliding engagement 
with the outwardly facing surface of the other guide rail. Therefore, when 
the frame of the assembly is in a lowered (vertical) or partially lowered 
position, an operator may simply grasp the footrest extension, slide it 
into a raised position in which the bearing element confined within each 
slot is at the upper or proximal end of that slot, and then pivot the 
footrest extension into a forwardly and upwardly angled position. With the 
footrest extension so oriented, that extension may be lowered into any of 
a multiplicity of positions along the length of the guide slot and then 
set in place by allowing the front or distal end to swing downwardly until 
the footrest extension is generally perpendicular in the frame. Should the 
forwardly-projecting footrest extension later engage an obstacle as the 
chair is being lowered, the footrest extension will simply pivot upwardly 
to accommodate the obstruction. On the other hand, should the footrest 
extension and frame be vertically aligned and fully extended, and should 
the footrest extension then engage an obstruction (for example, the foot 
of an operator standing in close proximity to the chair) as the chair or 
table descends, the footrest extension will automatically retract in a 
generally vertical plane. 
Other features, objects, and advantages of the invention will become 
apparent from the specification and drawings.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
FIG. 1 shows a power-operated multi-position table 10 (or table/chair) of a 
type particularly useful for medical examinations and minor surgery. The 
table has a power-operated telescoping pedestal 11, a base 12, and a top 
13 composed of seat section 13a, back section 13b, headrest section 13c, 
and leg and foot support section 13d. The telescoping pedestal 11 may be 
extended or retracted under power between the fully raised position shown 
in FIGS. 1 and 3 and a lowered position as depicted in FIG. 2. Although 
not shown, the seat section 13a (and the top 13 as a whole) may be power 
driven into rearwardly or forwardly tipped positions when the table is to 
be adjusted into Trendelenburg or reverse Trendelenburg orientation. In 
addition, the backrest 13 may be raised (FIG. 2) or lowered (FIGS. 1, 3), 
and the leg/foot support assembly 13d may also be raised (FIG. 1) or 
lowered (FIG. 3), all under power developed through electric motors and 
suitable transmissions concealed within the pedestal 11 and top 13. Only 
one such motor and its worm-drive transmission 14 are shown in the 
drawings (FIG. 7). It is to be understood that other types of power drives 
well known in the art, such as hydraulic motors or a combination of 
electric and hydraulic power systems, might be used. The entire structure 
is referred to as a "table" but it may also be properly designated as a 
chair since it is fully capable of being used as an examination chair when 
the pedestal is lowered, the backrest fully raised, and the leg/foot 
support assembly lowered (FIG. 2). It is also to be understood that 
details of the table/chair 10 are presented only for purposes of 
illustration and that the leg and foot support assembly with which this 
invention is specifically concerned might be used in conjunction with 
other types of power-operated multi-position tables, chairs, or 
table/chairs. The particular examination table/chair shown in the drawings 
is a Model 1K2 table, Hamilton Industries, Two Rivers, Wisconsin. 
The leg and foot support assembly 13d has two main components: a frame 15 
and a footrest extension 29. The frame is of generally rectangular 
box-like configuration equipped at its proximal end with a pair of support 
arms 16 pivotally connected to seat section 13a for pivotal movement 
between a raised or horizontal position, in which the frame is in planar 
alignment with the seat section 13a (FIGS. 1, 4, 7, 9) and a fully lowered 
vertical position in which the plane of the support assembly extends at 
right angles to the seat section (FIGS. 1 (broken lines), 2, 3, 10). The 
frame encases the motor 14 and its transmission, the latter being 
operatively connected by shaft 17 to seat section 13a. Retraction or 
extension of that shaft causes the frame to swing downwardly or upwardly 
about horizontal pivots 18 that hingedly connect the frame to the seat 
section. It is to be understood that the frame may also be pivoted into 
any of a variety of partially-lowered (or partially-raised) positions as 
indicated, for example, in FIGS. 5 and 6. 
The rectangular frame 15 has a pair of side walls 15a extending along 
spaced, parallel, vertical planes. A cover 19 extends over the frame and 
projects laterally outwardly beyond the lateral surfaces of the side walls 
15a to define a first pair of upper guide rails 20 extending 
longitudinally along opposite sides of the frame between the proximal and 
distal ends thereof. As illustrated in FIG. 8, the cover or top panel may 
have its side portions folded inwardly so that the rails 20 are of double 
thickness and are thereby strengthened or reinforced. 
A second or lower rail 21 extends longitudinally along each side wall and 
is spaced beneath the first or upper rail 20 to define an elongated guide 
slot or channel 22 therebetween. Each lower guide rail 21 is screwed or 
otherwise rigidly secured to a side wall 15a of the frame. The guide slot 
22 along each side of the frame is of uniform width (height) throughout 
its full extent except for a series of arcuate longitudinally-spaced 
notches 23 formed along the inwardly-facing surface 21a (i.e., the upper 
surface facing into guide slot 22). The second or lower guide rail 21 also 
provides a straight outwardly-facing guide surface 21b; that is, a surface 
that faces outwardly away from guide slot 22 (downwardly, when the support 
assembly is in the raised position depicted FIGS. 7-9). 
The first or upper guide rail 20 is also provided with an inwardly-facing 
guide surface 20a, which faces into guide slot 22, and an outwardly-facing 
guide surface 20b which is directed away from the guide slot. Again, as 
shown in FIGS. 7 and 9, inwardly-facing guide surface 20a is directed 
downwardly, and outwardly-facing guide surface 20b is directed upwardly, 
when the frame 15 is in a horizontal or raised position. 
As shown most clearly in FIGS. 9 and 12, the guide slot 22 is blocked off 
near the proximal end of the frame by an extension 25 of the second guide 
rail 21. Such extension serves as stop means at the proximal end of the 
slot and also provides an arcuate guide surface which merges smoothly with 
the outwardly-facing guide surface 21b of guide rail 21. It will also be 
observed that a recess or notch 26 is formed in each of the proximal 
corners of cover plate 19 and that one edge 26a of the recess is flush 
with arcuate guide surface 25a. Stop means may also be provided at the 
opposite (distal) end of the slot 22 in the form of stop pin or screw 27 
(FIGS. 7, 11). 
The second major component of the assembly, the footrest extension 29, is 
also generally rectangular in configuration and includes a pair of 
parallel side members 30, a top member or panel 31 that bridges the side 
members, and a front or distal member 32. The elongated side members 30 
extend along the side walls 15a of the frame 15 in close proximity to 
those walls (FIG. 8). Each side member 30 is provided adjacent its 
proximal end with a pair of bearing elements 33 and 34 extending towards 
the adjacent side wall 15a of the frame. One of the bearing elements 34 is 
confined within guide slot 22 for longitudinal movement along that slot 
and also for pivotal movement within certain constraints imposed by other 
elements of the assembly. Bearing element 34 may be solid or may take the 
form of a roller assembly; in the embodiment illustrated, the bearing 
element is in the form of a generally cylindrical pin or peg that is 
welded or otherwise rigidly secured to side member 30 intermediate the 
upper and lower longitudinal edges thereof. 
Bearing element 33 is of the same construction as element 34 and is 
parallel to the first element. It will be noted from the drawings, 
however, that bearing element 33 is spaced both proximally and 
transversely (vertically, when elongated member is horizontally oriented) 
from bearing element 34. The spacing is important and is related to the 
thicknesses of the guide rails 20 and 21 as well as the guide slot 22 
extending therebetween. Specifically, the diameter of bearing element 34 
should be slightly less than the width of guide slot 22 for the purpose of 
facilitating sliding movement of the bearing element along that slot and 
also to permit slight pivotal movement of the footrest extension 29 in 
relation to frame 19 regardless of the position of adjustment of the 
footrest extension, as will be described in greater detail hereinafter. 
The longitudinal spacing x between bearing elements 33 and 34 should 
closely approximate the thickness x' of the second guide rail 21 (FIGS. 8 
and 15); where the guide rail is provided with notches 23 as shown, then 
the thickness of that rail should be measured from the depth of each notch 
23 to the outwardly-facing bearing surface 21b (FIG. 8). The transverse 
spacing y between bearing elements 33 and 34 should approximate, but 
slightly exceed, the thickness y' of the first or upper guide rail 20 
(FIGS. 8, 15). 
Referring to FIGS. 7 and 9, top panel 31 extends to the distal end of the 
footrest extension but terminates well short of the proximal end thereof. 
Stated differently, the side members 30 extend proximally beyond the 
proximal end of top panel 31. A first cushion 40 is fixed to the proximal 
end of the frame and, when the footrest extension is in its retracted 
condition (FIGS. 7, 1), occupies most of the surface of cover plate 19 
proximal to the top panel 31 of the footrest extension. The footrest 
extension 29 is provided with its own cushion 41 which is substantially 
larger than cushion 40, covering the entire top panel 31 and, preferably, 
extending a limited distance alongside side members 30 and front member 
32. 
The underside of the cover panel 31 of footrest extension 29 has a 
reinforcing inner shell 42 shown most clearly in FIGS. 7 and 9. A latching 
member or tongue 43 projects downwardly from the underside of the shell 
and is engagable with a stop member or block 44 secured to the cover plate 
19 of frame 15 when the footrest extension 29 is retracted (FIG. 7). 
Because of the size differential between the diameter of lower (second) 
bearing element 34 and the distance between inwardly-facing guide surfaces 
20a and 21a (FIG. 8), the distal or front end of the footrest extension 29 
may be lifted or pivoted upwardly just far enough for tongue 43 to clear 
block 44, thereby permitting the footrest extension to be pulled 
horizontally outwardly as depicted in FIG. 4. When the footrest extension 
has reached the forward or distal limits of its travel, the stop block 44 
is engaged by a depending flange 46 along the distal (rear) edge of top 
panel 31 (FIG. 9). Therefore, FIGS. 7 and 9 show the footrest extension at 
the limits of its travel in a longitudinal direction along support frame 
15. 
For general examination, or for Trendelenburg or reverse Trendelenburg 
orientation of a patient, the leg and foot support assembly 13d would be 
elevated into the raised position shown in FIGS. 1, 7, and 9, and the 
footrest extension would be shifted forwardly or rearwardly to meet the 
requirements of the medical procedure and to provide proper support for 
the patient. For other types of examinations and chair positions, assembly 
13d would be pivoted under power into a partially or fully lowered 
position. When the assembly is fully lowered (FIG. 10), the footrest 
extension is still capable of being slid upwardly and downwardly within 
the limits provided by the guide rails 20 and 21, guide slot 22, and stop 
means 25 and 44. Should the footrest extension 29 be fully extended 
downwardly as shown in broken lines in FIGS. 3 and 10, and should the 
footrest extension then engage an obstruction as the table 10 is driven 
downwardly under power into a lowered position, the footrest extension 29, 
upon engaging such obstruction, will simply slide into a retracted 
position as the table top continues to descend (note arrow in FIG. 10). 
The footrest extension may of course be latched in a fully raised position 
by sliding it upwardly until tongue 43 clears stop block 44 and the end of 
the tongue bears against the block in the manner previously described. 
During longitudinal sliding movement of the footrest extension (whether the 
entire assembly 13d is horizontal, vertical, or some angular position in 
between) bearing element 34 rides along slot or channel 22 and bearing 
element 33 slidably engages the outwardly-facing guide surface 20b of the 
first guide rail 20. If the user wishes to pivot the footrest extension 29 
into a position at generally right angles to the frame 15, the footrest 
extension is first slid into its fully retracted position, with bearing 
member 34 engaging stop means 25, and then the free distal end of the 
footrest extension 29 is swung away from the frame 15 as depicted in FIGS. 
11 and 12. Bearing element 33, having been shifted beyond the distal 
limits of guide rail 20, passes through notch or recess 26 and travels 
along the arcuate guide surface 25a leading to the outwardly facing guide 
surface 21b of rail 21. Pivotal movement of the footrest extension is 
continued until the extension passes beyond a position at right angles to 
frame 15; under such circumstances, the direct spacing between bearing 
elements 33 and 34 exceeds the width or thickness of guide rail 21 and the 
footrest extension may easily be adjusted vertically into any selected 
position (FIG. 13). Once such a position is determined, the footrest 
extension is allowed to swing downwardly until it is generally 
perpendicular to frame 15. Where notches 23 are provided along the 
inwardly-facing surface 21a of guide rail 21, bearing element 34 is 
received within any one of such notches to provide positive locking action 
against upward and downward sliding movement of the footrest extension 29 
(FIG. 14). During vertical adjustment of the footrest extension, and when 
that extension is locked in a selected position of adjustment, bearing 
element 33 engages, or is free to engage, the outwardly facing guide 
surface 21b of guide rail 21. 
Should the footrest extension be oriented in the forwardly-projecting 
position shown in FIGS. 14 and 2 (broken lines), and should such extension 
engage an obstacle as the power-operated table descends, the front or 
distal end of the footrest extension may freely pivot upwardly into the 
position shown in FIG. 13, thereby avoiding damage to furniture or medical 
appliances that might be located in close proximity to the table, or 
injury to a doctor, nurse, or assistant, that might otherwise result from 
such contact. 
The frame 15 has been shown and described as having a pair of longitudinal 
side walls 15a, each with a pair of rails 20 and 21 for guiding movement 
of bearing elements 33 and 34 carried by opposite side members 30 of 
footrest extension 29. While such an arrangement is preferred for a number 
of reasons (e.g., increased stability, ease of manipulation, smoothness of 
operation, and availability of space within the frame for other components 
such as power drive elements), it is possible that satisfactory results 
might be achieved if only a single set of rails 20 and 21 were provided 
for guiding only one set of bearing elements 33 and 34. The rails need not 
project from a side wall but might extend along some other vertical and 
longitudinal wall such as, for example, a wall located between and 
parallel with the side walls of the frame. In any case, at least one set 
of rails 20 and 21 must be provided for guiding bearing elements 33 and 34 
so that the footrest extension may be retracted, extended, pivoted, and 
locked in its various positions of adjustment. 
While in the foregoing we have disclosed an embodiment of the invention in 
considerable detail for purposes of illustration, it will be understood by 
those skilled in the art that many of these details may be varied without 
departing from the spirit and scope of the invention.