CROSS REFERENCE TO RELATED APPLICATION  
       [0001]    This application claims the benefit of U.S. Provisional Application Serial No. 60/361,427, entitled, “PROSTHETIC ANNULAR COUPLING SOCKET ADAPTOR WITH ADJUSTABLE CLAMP”, filed on Feb. 28, 2002, the disclosure of which is incorporated herein by reference. 
     
    
     
       BACKGROUND  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates to prosthetic devices, and more particularly, to prosthetic couplings having annular coupling socket adapters (aka, “pyramid receivers”) with adjustable height tube clamps.  
           [0004]    2. Description of the Related Art  
           [0005]    As shown in FIG. 1, an example of an above-knee (“AK”) prosthetic limb  2  for a patient may include a prosthetic limb socket  4  for receiving the wearer&#39;s residual limb, a knee joint assembly  6 , a first pylon  8  coupled between the prosthetic limb socket  4  and the knee joint assembly  6 , interconnection components  10  for coupling the first pylon  8  to the prosthetic limb socket  4 , interconnection components  12  for coupling the first pylon  8  to the knee joint assembly  6 , an ankle/foot assembly  14 , and a second pylon  16  coupled between the knee joint assembly  6  and the ankle/foot assembly  14 . The interconnection components  10  may consist of a locking or suction assembly  18  (such as, for example, a Shuttle Lock component commercially available from Prosthetic Design, Inc.) positioned within a distal end of the prosthetic limb socket  4 , the conventional pyramidal link-plate  20 , and a pyramid receiver  22  for coupling the first pylon  8  to the distal boss  24  of the pyramidal link-plate  20 . Likewise, the interconnection components  12  may consist of the conventional pyramidal link-plate  20  mounted to the knee joint assembly  6  and another pyramid receiver  22  for coupling the first pylon  8  to the distal boss  24  of the pyramidal link-plate  20 . The plurality of set screws  26  are tightened, thus securely mounting the pyramidal link-plate  20  to the pyramid receiver  22 .  
           [0006]    As shown in FIG. 2, a prior art prosthetic pyramid receiver  22  includes a pyramid receiver portion  30  and a diametrically restrictable tube portion  32 . The tube portion  32  includes a ring-clamp  34 , a screw  36  and a washer, 38 . The pyramid receiver portion  30  has a concave upper mouth  33  adapted to mate with the domed structure  40  of a pyramid  42 . Angled holes  44  extend from the exterior surface and continue inward, thereafter extending into the interior channel of the pyramid receiver portion  30 . These holes  44  are adapted to receive set screws  46  for throughput. When tightened to engage the surfaces  48  of the frustropyramidal boss  50 , the pyramid  42  is pulled toward the pyramid receiver portion  30  until the domed structure  40  of the pyramid  42  engages the concave upper mouth  33  of the pyramid receiver portion  30 . Thereafter, further movement between the domed structure  40  of the pyramid  42  and the concave upper portion  33  of the pyramid receiver portion  30  is minimal (collectively the elements). Further tightening of the set screws  46  increases the amount of force required axially to move the elements in relation to one another, eventually “locking” the elements together for all intents and purposes.  
           [0007]    In fitting prosthetic limbs to patients, it is often necessary for the prosthetist to modify the lengths and/or orientations of various prosthetic limb components with respect to each other during initial fitting, or after the patient has worn the prosthetic limb for a period of time. The prosthetist attempts to maintain the alignment of the prosthetic components along the TKA line; a line parallel to the trochanter, knee and ankle. A pylon, in particular, is capable of being ground down or cut so as to shorten the length of the pylon to accord proper fitting. Problems sometimes arise when the pylon is ground down or cut, thereby shortening its length beyond that which is required. This necessitates the procurement of a completely new pylon. Alternatively, if the original pylon is too short, the current state of the art provides no alternative for the prosthetist other than procuring another pylon having a greater length.  
           [0008]    Accordingly, there is a need for a pyramid receiver and associated tube clamp that provides axial height adjustability with respect to pylon length. Alternatively, there is a need for a system in which a prosthetist may simply exchange different height spacers or bushings to be placed within the tube of the tube clamp, between an axial shoulder in the tube and the end of the pylon, to adjust the height of the pyramid receiver with respect to the pylon.  
         SUMMARY OF THE INVENTION  
         [0009]    In a first exemplary embodiment of the present invention, a height-adjustable prosthetic coupling is provided that has an annular coupling adapter (pyramid receiver) on one end and a diametrically restrictable tube (tube clamp) on the opposing end, which allows for height (axial) adjustment between the coupling and a prosthetic pylon. The diametrically restrictable tube has an internal depth which accommodates the insertion of a portion of the pylon. Conventional pyramid-receiver tube clamps have a diametrically restrictable tube of a minimal length sufficient to provide enough surface area to securely lock the tube clamp onto the pylon. One reason for minimizing this length is to reduce the material costs for such components. The first exemplary embodiment of the present invention, on the other hand, provides a diametrically restrictable tube having an internal depth which can accommodate more than the minimum length of the pylon necessary for properly securing the pylon to the coupling. In other words, the interior height of the tube is greater than prior art tubes. When the patient requires the overall length between the tube clamp and pylon to be adjusted, the prosthetist “frees up” the diametrically restrictable tube so as to enable movement between the internal surface of the tube and the exterior surface of the pylon. Once the desired overall length is reached, the prosthetist restricts the diametrically restrictable tube and prevents noticeable movement between the pylon and tube; both in the vertical, and in the rotational/axial direction. Thus, the present invention provides for human errors in measuring and provides adjustability to meet the patient&#39;s needs and may not require the procurement of a plurality of pylons of varied lengths.  
           [0010]    Likewise, the elements of the first exemplary embodiment may be combined with bushings (or spacers) that fill any potential axial void that may be present in the first exemplary embodiment between the shoulder of the coupling extending radially into the channel of the tube and the longitudinal end-surface of the pylon; resulting in a second exemplary embodiment. The second exemplary embodiment provides a plurality of variable-height axial bushings that are insertable into the tube of the coupling before the pylon is inserted. One or more of these bushings may be inserted to fill any potential void between the coupling and the longitudinal surface of the pylon. Thus, the adjustment of the prosthetic components may be made easier for the prosthetist because the weight of the tube clamp and associated prosthetic components may be pressed onto the pylon without the fear of hampering the measurements surrounding the proper depth of the pylon.  
           [0011]    It is a first aspect of the present invention to provide a prosthetic coupling comprising an annular coupling adapter having a coupling end and an opposed pylon mounting end, the coupling end including a central bore adapted to receive, and be coupled to a prosthetic limb pyramid component, where the pylon mounting end includes a diametrically restrictable tube with at least two circumferential discontinuities and an axial depth with a predetermined extension greater than a minimum depth required to adequately secure a prosthetic limb pylon component therein, where the predetermined extension provides the prosthetic coupling height adjustability with respect to the prosthetic limb pylon to which it is adapted to be secured.  
           [0012]    It is a second aspect of the present invention to provide an adjustable prosthetic coupling comprising a pylon receiving end having an inner ring for captively engaging a prosthetic pylon therein, the inner ring including at least two arcuate segments being diametrically constrictable, an outer ring circumscribing the inner ring and, a prosthetic component interface end for engaging and securing a prosthetic component thereto, where the pylon receiving end accommodates varying depths of insertion of the prosthetic pylon beyond the minimum required for secured fitting to enable height adjustability.  
           [0013]    It is a third aspect of the present invention to provide an adjustable prosthetic coupling comprising a pylon receiving portion having a means for selectively securing a prosthetic pylon therein and, a pyramid receiving portion including a means for selectively securing a prosthetic pyramid thereto, where the means for selectively securing the prosthetic pylon therein includes a plurality of height adjustments between the prosthetic pyramid and the prosthetic pylon, and the means for selectively securing the prosthetic pylon therein enables day-to-day use.  
           [0014]    It is a fourth aspect of the present invention to provide a method for custom fitting prosthetic devices, comprising the steps of: providing a prosthetic coupling device adapted to couple a prosthetic pylon to a second prosthetic limb component, the coupling device having a concavity adapted to interface with a prosthetic pylon, the cavity accommodating various depths of pylon insertion to provide height adjustability with the second prosthetic limb component, the coupling device further being designed for day-today use; and, mounting the prosthetic component to the prosthetic pylon so as to provide a secure coupling between the prosthetic component enabling day-to-day use. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    [0015]FIG. 1 is a perspective view of a prior art prosthetic limb assembly;  
         [0016]    [0016]FIG. 2 is a perspective view of a prior art pyramid receiver;  
         [0017]    [0017]FIG. 3 is a perspective view of a first exemplary embodiment of the present invention;  
         [0018]    [0018]FIG. 4 is an exploded view of the first exemplary embodiment of the present invention;  
         [0019]    [0019]FIG. 5 is a frontal view of the first exemplary embodiment of the present invention;  
         [0020]    [0020]FIG. 6 is a left side view of the first exemplary embodiment of the present invention;  
         [0021]    [0021]FIG. 7 is an overhead view of the first exemplary embodiment of the present invention; and  
         [0022]    [0022]FIG. 8 is a cross sectional view of the first exemplary embodiment of the present invention along lines  6 - 6  of FIG. 7.  
         [0023]    [0023]FIG. 9 is an underneath view of an alternate exemplary embodiment of the present invention having two integrated tube clamps. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]    The exemplary embodiments of the present invention are described and illustrated below as prosthetic limb couplings, for mounting a first prosthetic component to a second pylon component, that include height-adjustable tube clamps for mating with pylon components. The various orientational or positional terms used to describe the elements of the inventions are therefore used according to this frame of reference. Of course, it will be apparent to those of ordinary skill in the art that the preferred embodiments may also be used in combination with one or more prosthetic components to function as a complete prosthetic assembly. In such a case, the orientational or positional terms may be different. However, for clarity and precision, only a single orientational or positional reference will be utilized; and, therefore it will be understood that the positional and orientational terms used to describe the elements of the exemplary embodiments of the present invention are only used to describe the elements in relation to one another. For example, a pylon will have two opposing longitudinal surfaces; one being characterized as proximal, while the other is characterized as distal. Yet, the pylon may be rotated in space, thereafter transforming the proximal end into the distal end and vice versa without departing from the scope and spirit of the present invention.  
         [0025]    As shown in FIGS.  3 - 8 , a first exemplary embodiment of the present invention  52  provides a prosthetic coupling  52  having a titanium pyramid receiver  54  on the proximal end, and a titanium tube  56  on the distal end with an aluminum ring clamp  58  mounted thereto. The pyramid receiver  54  has a proximal opening with a mouth  60  having a conical interior surface  61  that is machined or molded to mate with a “male” prosthetic limb component such as, for example, a conventional prosthetic pyramid  62 . The pyramid receiver  54  also includes at least two diametrically opposed holes  64  angled distally in relation to an imaginary planar surface parallel to the proximal end of the pyramid receiver  54 . Each angled hole  64  may be machined or molded to house a single set screw  66 ; the set screws maybe {fraction (5/16)}-18 socket head set screws.  
         [0026]    Referencing FIG. 2, the pyramid  42  includes a frustropyramidal, four-sided boss  50  projecting from a domed shaped, or spherically convex base  40  (hereafter domed portion). The pyramid  42  is secured to another prosthetic component with four screws (a standard industry design). These four screws attach the pyramid  42  firmly to a prosthetic component (not shown) and provide structural support at the proximal end for connection between the prosthetic pyramid  42  and the prosthetic pyramid receiver  54 .  
         [0027]    Mounting the pyramid  42  to the pyramid receiver  54  begins by placing the frustropyramidal boss  50  within the concave mouth  60  of the pyramid receiver proximal opening so as to enable the set screws  66  to engage the faces  48  of the frustropyramidal boss  50 . Concurrently, as the set screws  66  are engaging the faces  48  of the frustropyramidal boss  50 , the domed portion  40  of the pyramid  42  is being moved closer to the concave mouth  60  of the pyramid receiver  54 . As the pyramid  42  comes in close proximity to the pyramid receiver&#39;s  54  interior conical surface  62 , the exterior surface of the domed portion  40  abuts the conical interior surface  62  of the pyramid receiver  54  and a friction fit results. The tighter the set screws  66  push against the faces  48  of the frustropyramidal boss  50 , the relatively better the friction fit. In other words, the higher the force the set screws  66  exert against the faces  48  of the frustropyramidal boss  50 , thus pushing the pyramid  42  against the pyramid receiver  54 , the greater the amount of force required to unseat the pyramidal receiver&#39;s  54  interior conical surface  62  from the domed portion  40  of the pyramid  42 . This results in relatively no movement between the two elements in either the vertical or rotational direction when the set screws  66  are sufficiently tightened.  
         [0028]    As shown in FIG. 4, the tube  56  includes two discontinuities in the form of channels  78  extending therethrough and upward from a distal end thereof, which separate at least two circumferential portions of the tube  56  from one another. The channels  78  terminate with the formation of a stress riser  80  to dissipate stress and inhibit the formation or a stress crack at the point of termination. These channels  78  are in part what provides the flexibility of the tube  56  to conform to a plurality of internal diameters, thereby supplemented by the adjustable aluminum ring clamp  58  which provides the restrictive force. The exterior of the tube  56  includes a lip or shoulder  82  extending radially from the tube  56  that is adapted to abut the proximal surface of the ring-clamp  58 . Extending distally from the lip  82 , the outer circumferential surface of the tube  56  is recessed to mate with the inner diameter of the ring clamp  58 .  
         [0029]    The restrictable aspect of the ring clamp  58  includes a radial projection  84  that takes on a pyramidal shape which exhibits an apex in exterior diameter at the axial center of the clamp and diminishes proportionally in the vertical and radial directions accordingly, thus providing an outer surface  86  which slopes in the axial as well as distal and proximal directions. A break  88  effectively bisects the radial projection of the ring clamp  58 , providing complimentary, mirror image planar surfaces  90  parallel to the TKA line. Perpendicular to the break  88  of the ring clamp  58  is a hole  92  which extends through the pyramid shaped radial projection  94  of the ring clamp  58 . The hole  92  extends through the complimentary parallel planar surfaces  90  created by the break  88 . This hole  92  may be machined or molded so as to accept a threaded device such as a screw  94 ; the screw may be a # 10 - 32  socket head cap screw. The screw  94  facilitates the restrictive force necessary to bring the parallel surfaces  90  of the ring clamp  58  closer together than compared to equilibrium without the screw  94 , such that the internal diameter of the tube  56  at the distal end becomes variable; generally smaller in diameter when restrictive force is applied.  
         [0030]    It is preferred, but not necessary, that the adjustable aluminum ring clamp  58  be mounted on the distal end of the hollow titanium tube  56 . One example of how this might be accomplished is by way of a retention pin  96  that is friction fit within a hole  98  radially bored through the ring clamp  58  and the tube  56 . When the retention pin  96  is in place, free rotation and axial separation of the ring clamp  58  from the tube  56  is inhibited. In any such mounting technique, it is preferred, but not necessary, to align the break  88  with at least one channel  78 .  
         [0031]    An inner concavity  100  of the tube  56  provides a “female” interface between the coupling  52  and a second prosthetic component such as, for example, a graphite pylon. The interior surface of the tube  56  which makes contact with the exterior surface of the pylon (not shown) may be smooth or of non-uniform texture and include a taper approximating its distal end to effectively provide a maximum axial depth for insertion of the pylon. In this exemplary embodiment, the maximum axial depth is one-half inch longer than the minimum depth necessary to provide sufficient surface area to achieve secure locking (as required by the ISO  10328  torque test) between the coupling  52  and the pylon. This additional one-half inch depth of the tube  56  provides height adjustability for the component as will be discussed further below.  
         [0032]    The pylon is generally a cylindrical shaft having a uniform circular cross section. The pylon has two longitudinal end surfaces which make up the respective distal and proximal ends of the pylon. Assembly of the pylon into the tube  56  of the coupling  52  begins by inserting the proximal end of the pylon into the tube  56  until the pylon abuts the shoulder  102  inside of the tube  56 . Using a paint marker, the exposed portion of the pylon immediately adjacent to the ring-clamp is marked. The pylon may then be withdrawn from the tube  56  up to one-half inch by sliding the coupling  52  away from the pylon; all the while providing at least the minimum pylon insertion depth. This minimal pylon insertion depth being the depth at which enough of the exterior surface of the pylon is in potential contact with enough of the interior surface of the tube  56  such that a resulting friction fit between the two elements will disallow substantial rotational and/or vertical movement between the two during day-to-day use of the prosthetic limb by the patient. Thereafter, the ring clamp  58  is restricted by use of the screw  94 . An application of Loctite® may be applied before tightening the screw to help maintain the proper restrictive force.  
         [0033]    Alternatively, to adjust the pylon to coupling  52  distance, the prosthetist may simply measure down from the proximal longitudinal surface of the pylon and mark the exterior surface of the pylon corresponding to the minimum insertion depth. Thereafter, the prosthetist may make vertical adjustments of the pylon so long as the marked exterior surface of the pylon is inserted into the tube  56 .  
         [0034]    Additionally, the prosthetist may adjust the pylon length after the initial fitting of the patient&#39;s prosthetic components. In this case, the prosthetist begins by loosening the ring clamp  58  around the tube  56 , thus enabling vertical and/or rotational movement between the coupling  52  and the pylon. Next, the prosthetist simply pulls a portion of the pylon out from the tube  56 , up to one-half inch until the proper measurements are met if the distance is too short; conversely, the prosthetist simply pushes a portion of the pylon into the tube  56 , up to one-half inch until the proper measurements are met if the distance is too great; all the while keeping the minimum amount of exterior pylon surface in potential contact with the minimum amount of interior surface of the tube  56  such that a friction fit between the two elements will be maintained with proper tightening of the ring clamp  58 . While the prosthetist is adjusting the length between the distal end of the pylon and the proximal end of the coupling  52 , it will be recognized by one of ordinary skill in the art that other concerns may be addressed by the prosthetist such as alignment retention of the prosthetic components attached to either the distal end of the pylon, or the proximal end of the coupling  52 . Finally, the prosthetist tightens the ring clamp  58  by torquing the screw  94  to the setting recommended by the manufacturer and the adjustment is complete.  
         [0035]    As a caveat to the aforementioned procedure for adjustability, it will also be recognized by one of ordinary skill in the art that if the amount of the pylon inserted into the tube is the minimum amount necessary for a proper friction fit, adjustability to a greater length may require: the procurement of another pylon having a longer length; adjusting the prosthetic component mounted to the distal end of the pylon; or, exchanging a coupling  52  having a greater tube  56  height.  
         [0036]    It will be apparent to those of ordinary skill that the one-half inch extension of the tube of the tube clamp provided in the first exemplary embodiment is not limiting, and it is within the scope of the invention to provide extensions having longer or shorter lengths as desired.  
         [0037]    The ring clamp  58  may be of the same or a similar material or of an alloy comprising one or more of the materials of the tube  56  and/or pyramid receiver  54 . Materials suitable for use in the fabrication of the tube  56 , the pyramid receiver  54 , and the ring-clamp include elemental metals, alloys of elemental metals, composites, and any other similar materials. It is preferred that the material chosen for the tube  56  inhibits any permanent deformation attributable to the ring clamp  58 .  
         [0038]    It is likewise within the scope and spirit of the invention to provide grooves on the outer circumferential surface of the tube  56  that mate with corresponding grooves in the ring clamp  58  to align the ring-clamp  98  to the proper exterior surface of the tube  56 , thus maintaining the ring clamp&#39;s  58  axial position around the tube  56  when the ring clamp  58  is not sufficiently tightened.  
         [0039]    In the first exemplary embodiment  52 , the clamp is separate from the manufacture of the tube  56 . However, it is within the scope and spirit of the present invention to provide a titanium ring clamp  58  incorporated into the tube  56  and/or pyramid receiver  54 .  
         [0040]    It is also within the scope and spirit of the present invention to provide a set of bushings or spacers having incremental axial height and uniform circular cross section. In this embodiment, these bushings may be inserted into the tube  56  whenever the measurements taken by the prosthetist indicate that the proximal end of the pylon will not abut the shoulder  102  within the tube  56 . The prosthetist begins by making a measurement of the overall length desired as measured from the distal end of the pylon to the proximal end of the coupling  52 . Next, the prosthetist marks or measures how much of the pylon will be inserted into the tube  56  for proper fitting. If this measurement is less than the height of the tube  56  available for pylon insertion, the prosthetist simply chooses a bushing having a height to make up the difference. It will be understood by those of ordinary skill in the art that the bushings do not act to provide a friction fit between the pylon and the tube  56 , but simply occupy a space or void that would normally be vacant. It is also within the scope of the invention that all or some of the spacers have equal height and are designed to be stackable upon one another.  
         [0041]    Another exemplary embodiment of the present invention provides a plurality of couplings  52  having incremental tube heights. This “set” of tube clamps, being interchangeable, provides a prosthetist flexibility regarding adjustments to the length between the proximal end of the coupling and the distal end of the pylon (overall length). As characterized above, this flexibility in tube height does not negate the requirement of a minimum pylon insertion depth for proper friction fitting. The set of couplings may be manufactured with any tube height for pylon insertion, so long as the set as a whole provides incremental adjustment of the overall length at least ranging one-half inch.  
         [0042]    Still another exemplary embodiment of the present invention is shown in FIG. 9. This exemplary embodiment provides two integrated clamps  104 ,  106  as part of the tube portion of the coupling. Each clamp includes a set screw  108 ,  110  that provides the restrictive force necessary to diminish the gaps  112  in the coupling conform the tube portion around a pylon thereby providing a friction fit sufficient to enable day-to-day use of the coupling by a patient. It is also within the scope of the invention to provide a set of couplings embodying such a dual clamp configuration that may be manufactured with any tube height for pylon insertion, so long as the set as a whole provides incremental adjustment of the overall length at least ranging one-half inch.  
         [0043]    Adjustability typically requires that the prior art tube clamp be loosened by the prosthetist enabling vertical and/or rotational movement between the pylon and tube clamp, so that measurement can be made to adjust the length/height of the pylon. However, using a set of couplings having incremental pylon insertion depths, the pylon is not adjusted. A prosthetist would remove the pylon and replace the coupling with another coupling having a different pylon insertion depth so as to provide the proper overall length for the patient. The pylon is thereafter inserted into the tube  56  until the proximal longitudinal end of the pylon abuts the shoulder on the inside of the tube. If applicable, other prosthetic components are reattached, all the while cognizant of proper alignment before final attachment and tightening of the screw. Generally, it is envisioned that this set be used without using the bushings as described above. However, it is within the scope and spirit of the present invention to also utilize the bushings if found advantageous by the prosthetist.  
         [0044]    If the prosthetist utilizes the set, bushings may be used in lieu of, or in addition to, the next or greater incremental sized coupling in the set. Here, adjustability starts with the prosthetist simply pulling a portion of the pylon out from the tube until the proper measurements are established if the current distance has been determined as being too short. All the while keeping the minimum amount of exterior pylon surface in potential contact with the minimum amount of interior surface (not shown) of the tube such that a friction fit between the two elements will be maintained with proper tightening of the screw. While the prosthetist is adjusting the length between the distal end of the pylon and the proximal end of the coupling, it will be recognized by one of ordinary skill in the art that other concerns may additionally be addressed such as alignment retention of the prosthetic components attached to either the distal end of the pylon, or the proximal end of the coupling. Once the proper distance is determined and/or marked, the pylon is removed from the tube. A bushing is inserted into the tube to accord the proper distance. Next, the pylon is inserted into the tube to abut the bushing which abuts the shoulder in the tube. Finally, the prosthetist tightens the clamp by tightening the screw to the proper torque setting recommended by the manufacturer and the adjustment is complete. As a caveat to the aforementioned procedure for adjustability, it will also be recognized by one of ordinary skill in the art that if the amount of the pylon inserted into the tube is the minimum amount necessary for a proper friction fit, adjustability to a greater length will not be possible without the procurement of another pylon having a longer length, or adjusting the prosthetic component attached to the distal end of the pylon, or switching couplings where the second coupling has a longer height tube. In addition, should the prosthetist desire to exchange couplings and utilize bushings, the procedure is analogous with that enunciated above, but begins with removal of the old coupling and insertion of a new coupling from the set.  
         [0045]    Following from the above description and invention summaries, it should be apparent to those of ordinary skill in the art that, while the methods and apparatuses herein described constitute exemplary embodiments of the present invention, it is to be understood that the inventions contained herein are not limited to these precise embodiments and that changes may be made to them without departing from the scope of the inventions as defined by the claims. Additionally, it is to be understood that the invention is defined by the claims and it not intended that any limitations or elements describing the exemplary embodiments set forth herein are to be incorporated into the meanings of the claims unless such limitations or elements are explicitly listed in the claims. Likewise, it is to be understood that it is not necessary to meet any or all of the identified advantages or objects of the invention disclosed herein in order to fall within the scope of any claims, since the invention is defined by the claims and since inherent and/or unforeseen advantages of the present invention may exist even though they may not have been explicitly discussed herein.
A prosthetic coupling comprising an annular coupling adapter having a coupling end and an opposed pylon mounting end, the coupling end including a central bore adapted to receive, and be coupled to a prosthetic limb pyramid component, where the pylon mounting end includes a diametrically restrictable tube with at least two circumferential discontinuities and an axial depth with a predetermined extension greater than a minimum depth required to adequately secure a prosthetic limb pylon component therein, where the predetermined extension provides the prosthetic coupling height adjustability with respect to the prosthetic limb pylon to which it is adapted to be secured. Such prosthetic couplings may be supplemented with bushings inserted within the pylon mounting end to inhibit further pylon insertion beyond a desired depth.