CRUTCH WITH PIVOTABLE FOOT SUPPORT
This application is being filed as a PCT International Patent application on 3 February 2005, in the name of Hal Joseph and Eberhard Zeh, both U.S. citizens, applicants for the designation of all countries, and claims priority to U.S. Provisional Application Serial No. 60/542,641, filed February 5, 2004.
Technical Field The present inventions relate to crutches and in particular, a crutch with a pivotal leg support for reducing edema.
Background The reduction of edema in the lower limbs, of humans that have weakened lower limbs, is a fundamental goal of the medical community. While a patient is active, a crutch may provide the means to reduce pressure to the lower weakened limbs. The crutch shifts the burden and weight from the lower limbs to the upper body. The most familiar apparatus is the common crutch, which fits under the arm of the patient and aids in walking. When the patient is at rest or inactive, elevating the limb may reduce the chance of developing edema. A number of different structures can elevate a limb off the floor when the patient is inactive. For example, a footstool, a stack of pillows or even a couch is available to most patients in their home. A common difficulty arises whea a patient, with a crutch, is not at home or has nothing to support his or her lower limb while he or she is sitting. Edema may result if the limb is not elevated in these situations. A variety of systems suggest a portable mechanism for supporting the limb of a resting patient. For example, U.S. Pat. No. 5,735,303 to Cole discloses a crutch that employs a pair of spaced legs that unfold from one a side of the crutch and rest on the ground to support the patient's lower limb. With the addition of folding sup ort legs, the Cole crutch is bulky, heavy and awkward for the patient to use. Therefore, a need exists for an integrated crutch with a foot support system that is lightweight and easy to use.
Summary of the Invention One embodiment of the current invention provides an integrated crutch with a foot support for use by a patient that is sitting that is lightweight, stable and easy to use. A single crutch leg with a normal position and a support position is used to create a foot support. In the normal position, the leg and leg extension support the
crutch frame and thus is designed for use by a walking patient. In the support position, the leg is pivoted from the frame to rest on the ground and support the base of the crutch. In this support position, the crutch is designed to support a patient's leg while sitting in a chair so that the patient's leg is extended horizontally. The leg extension, in this embodiment, couples to the leg while the leg pivo tally engages the frame members of the crutch. In the normal straight position, the leg and leg extension are pinned against a plate and axially positioned in line with the frame members. Unpinning the leg allows the lower leg and leg extension to swing down, forming an angle with the crutch frame members. A block and a brace fix the leg in place in the angled position, thereby creating a support for a patient's lower limb. A patient can then place the head of the frame under his hip on a chair and prop his foot onto the base of the crutch thereby elevating his leg to reduce the chance of edema forming. The base of the leg extension, in another embodiment, has foldable stabilizing wing arms. The stabilizing wings remain in a folded position when the leg is in a normal straight position. When the crutch is changed to the angled position, i.e., becomes a support, the wings can be unfolded and positioned to provide additional lateral stability and steadiness to the crutch leg support. The stabilizing wings attach to the base of the leg extension with a bracket. A slidable sleeve bushing secures the stabilizing wings in either a folded or unfolded position. Additional embodiments of the present invention will be apparent from a reading of the following detailed description of an exemplary embodiment, with reference to the accompanying drawing figures. Brief Description of the Drawings FIG. 1 is a front view of the lower portion of a conventional crutch. FIG. 2 is a front view of the crutch in accordance with an embodiment of the present invention. FIG. 3 is a rear view of the crutch of Figure 2 with the leg in a normal crutch position. FIG. 4 is a partial side view of the crutch shown in Figure 2. FIG. 5 is a side view of the crutch shown in Figure 2 with the leg in the support position. FIG. 6 is a front view of the crutch shown in Figure 5. FIG. 7 is a separate perspective view of a locking block. FIG. 8 is a separate perspective view of the brace member.
FIG. 9 is an enlarged bottom-end view of the crutch shown in Figure 2 with a pair of support wings extended to provide lateral support to the crutch shown in Figure 2 in the support position. FIG. 10 is a view of the bottom-end of the crutch with the locking sleeve lifted so that the support wings may be rotated upward into a retracted position. FIG. 11 is a view of the bottom-end of the crutch with the support wings retracted and locked for use of the crutch in a normal position. FIG. 12 is a cross sectional view taken along the line 12-12 in FIG. 11. Detailed Description of the Invention Figure 1 is a front- view of a conventional crutch 10. The conventional crutch 10 is able to expand vertically to accommodate persons of differing heights by use of pins in a leg extension 11 engaging any number of holes 12 is a leg 14. The leg 14 is in turn fastened to a pair of frame members 16 via rivet pins 18 and 20. Figure 2 is a similar view as in Figure 1 but showing a crutch 100 in accordance with an embodiment of the present invention. The crutch 100 has a leg 102 and a leg extension 104. To accommodate the pivoting of the leg 102, the leg 102 and the leg extension 104 are somewhat longer than a conventional crutch 10 shown in Figure 1, while the frame members 106 are shorter than those in a conventional crutch 10. Preferably the leg 102 and the leg extension 104 are lengthened by approximately 3 inches and the frame members 106 are shortened by about 3 inches. The end result is a crutch 100 that is substantially the same overall size as a conventional crutch 10. The leg 102 attaches to the frame members 106 with a pivot pin 108 at the head-end of the leg 102. A plate 110 fastened to and located at the base of the frame members 106 acts as a stop, limiting the swing motion of the leg 102 and the leg extension 104. The plate 110 also acts as a locking base to secure the leg 102 when crutch 100 is a normal position. Figure 3 is a back- view of the lower portion of the crutch 100 revealing a brace 112 that has its upper end pivotally fastened to the crutch frame members 106 via a pivot pin 114. Its lower end is fastened to a locking sleeve block 116. Figure 4 shows the lower-end of the frame members 106 attached to the leg 102 in the normal position of the crutch 100. The locking sleeve block 116 is positioned such that the brace 112 is parallel to and in line with the frame members 106. In this position, the spring-biased pins 118 engage the plate 110 to lock the crutch 100 in a normal support position as shown in Figures 2 and 3. Figure 5 shows the crutch 100 in a support position, hi the support position the frame members 106 extend horizontally and the leg 102 and leg extension 104
are rotated downward to a vertical position to rest on a support surface such as a floor. In this position, a patient can sit in a chair with his hips resting on the upper- end of the crutch frame members 106. The distal ends of the frame members 106 are then held in a horizontal position by the vertical legs 102 and extension 104. In order to change from the normal position to the support position the spring biased pins 118 are pressed downward to unlatch the locking sleeve block 116 that then slides downward to a position engaging a pair of detents 124, shown in Figure 3 as the leg 102 is rotated from the normal position to the support position. In this support position, the brace 112 preferably forms the hypotenuse of a right triangle with the leg 102. A foot-end view of the crutch 100 in the support position is shown in Figure 6. A separate view of the locking sleeve block 116 is shown in Figure 7. The locking sleeve block 116 is a solid piece of either plastic or aluminum preferably, that has a separate axial bore 126 and a pair of opposing laterally extending axles 128 and a pair of lateral spring pins 130 below the axles 128, one of which is shown in Figure 7. The other spring pin 130 is obscured from view in Figure 7. The axles 128 receive the lower ends 132 of the brace 112. The spring pins 130 are designed to engage a pair of detents 124 shown in Figure 3 to hold the locking sleeve block 116 in the support position. A separate view of the brace 112 is shown in Figure 8. The brace 112 is an elongated generally straight plate member that has a curved cross sectional shape to curve around the leg 102 and the frame members 106, The brace 112 is preferably made of a strong (and rigid) material such as spring steel, which together with the curved cross section will give it the necessary rigidity. The upper-end of the brace 112 has a single rolled sleeve 134 through which the pivot pin 114 passes. The lower-end of the brace 132 is split into two legs, each terminating in a rolled sleeve 132 that fits over one of the axles 128. These axles may be threadably fastened into the block 116 to assemble the brace and block together. The brace 112 preferably has a central axial slot 122 to permit a patient to reach the pins in the leg extension 104 that fit into the holes in the leg 102 in order to change the overall length of the crutch 100 when the crutch 100 is in the normal position shown in Figures 2 and 3. Figure 9, 10, and 11 illustrate an optional support wing assembly 140 that maybe attached to the lower end of the leg extension 104 immediately above a foot 142 of the crutch 100. The support wing assembly 140 has a pair of stabilizing wing members 144 pivotally attached to a clamp bracket 146 that is clamped to the foot- end of the leg extension 104 just above the foot 142. The stabilizing wings 144 can be rotated down to a support position as shown in Figure 9 and raised as shown in Figure 10 to a retracted position shown in Figure 11. The support wing assembly
140 further includes a locking sleeve bushing 148 that slides over and engages a spring-biased pin 150 as shown in Figure 9 to retain the bushing 148 against the foot 142. In the position shown in Figure 9, the stabilizing wings 144 are retained at a 45 degree angle so as to rest on the support surface upon which the foot 142 rests in order to provide some additional lateral support to the crutch 100. To operate the support wing assembly 140, a patient can depress the spring pin 150 and lift the locking sleeve bushing 148 and slide it up the leg extension 104 so that the wings 144 may be rotated upward as shown in Figure 10 such that they lie against the leg extension 104. The locking sleeve bushing 148 can then be lowered back down over the wings 144 to the locked position with the spring pin 150 extended to retain the sleeve against the foot 142 as shown in Figures 10 and 11. The bracket clamp 146 is preferably made of aluminum. The stabilizing wings 144 are preferably made of spring quality stainless steel. The bushing 148 may b made of aluminum or made of a plastic material so as to minimize the weight addition to the crutch 100. A cross sectional view through the wings 144 and leg extension 104 is shown in FIG. 12. The leg extension 104 may have a pair of parallel sides while the wings 144 have an arcuate segment cross section so that when aligned together alongside the extension 104 they together present a circular cylindrical shape complementary to that of the bore through the sleeve bushing 148. This configuration is not mandatory as the central bore through the bushing 148 need not be circular in cross section, but is shown as a preferred configuration. While the invention has been described above with reference to particular embodiments, it is to be recognized that various changes modifications and alternatives may be provided. For example, the locking block 116 may be constructed other than as specifically shown. The configuration of the locking block 116 and lock plate 110 is simply one configuration of many that could be utilized. In addition, a different form of latching between block 116 and the plate 110 or along the leg 104 may alternatively be provided. Also, the shape of the brace 112 need not be particularly as shown in the figures. For example, the brace 112 may be constructed of two separate members rather than a single member.
Similarly, different configurations of the support wing assembly 140 are envisioned. For example, the wings 144 could be formed of curved sheet material having a radius complementary to the outside radius of the extension 104. This would facilitate a smaller, hence more lightweight, bushing 148 than shown in the drawing figures 9, 10 and 11. Those skilled in the art will undoubtedly recognize that other such various changes in form and detail may be made without departing from the spirit and underlying principles of the invention as defined by the following claims.