The Great Prosthetic Challenge: Difficult to Fit Cases

Case Study 1: Walking After 40 Years in a Wheelchair

The combination of bilateral transfemoral amputations, short residual limbs, and a decade or more without ambulation previously might have meant that a patient's remaining lifetime would be spent using a wheelchair. The task of ambulating at full height requires well-tuned balance, developed musculature, and sensitivity to the demands of various terrains. Relearning to ambulate as an adult also requires great psychological resilience. Without a systematic, graduated program that can bring mastery in stages, patients may become daunted by lack of predictable progress and return permanently to using a wheelchair. Hanger Prosthetics & Orthotics, Bethesda, Maryland, hosts an ongoing specialized training protocol that provides just such predictable progress.

History

Jim Delmar, an extremely fit 62-year-old Vietnam veteran with bilateral transfemoral amputations secondary to traumatic injury, contacted Bobby Coles, CP, and Kevin Carroll, CP, Hanger Prosthetics & Orthotics, for prosthetic fitting after using a wheelchair for almost 40 years.

Delmar's amputations were secondary to a landmine explosion in 1968. His left femur is 7.5 in. long, his right femur is 7 in., and both residual limbs are conical with healthy skin. Following his amputations, he attempted for two years to wear prostheses that comprised straight suction sockets, basic hydraulic knees, and a belt suspension system. Because his knees collapsed when he stood in them and he required two crutches to stand and walk, he became frustrated and ultimately rejected the prostheses and began using a wheelchair.

Approximately two years prior to receiving care from Carroll's team, Delmar had been inspired to walk again after seeing Staff Sgt. Heath Calhoun, a fellow bilateral transfemoral amputee who is a highly successful prosthesis user. Delmar was then fitted with microprocessor-controlled legs with a lanyard suspension and completed 52 sessions of physical therapy. He used foreshortened prosthetic legs (shorties) for approximately one hour per therapy session. He had attained some initial success in walking, but continued to struggle with getting sockets to fit and lock onto his residual limbs. Delmar's limbs would loosen inside of the sockets after approximately 20 minutes of walking.

Upon examination, Carroll's team discovered that when Delmar walked, muscle at the distal ends of his residual limbs contracted, breaking normal socket suction with their movement.

Development of a Prosthetic Solution

Figure 1: Jim Delmar, 62, spent almost 40 years in a wheelchair before learning to walk again.

Developing a solution for Delmar presented a two-fold problem: how do you provide an interface that would stay attached to his unusual residual limbs, and how do you train him to walk after almost 40 years of wheelchair use?

Interface

The prosthetic care team fitted Delmar with fabric-reinforced gel liners and ComfortFlex™ sockets. They then fitted a custom elevated suction system comprised of a modified locking pin system and distal end cap with a polyethylene shell.

Ambulation Training

Fundamental to successful gait training for bilateral transfemoral amputees is mastery of four phases: (1) Building of confidence in prostheses through physical training, education, and peer and family support; (2) walking on short legs, with achievement of mastery over a period of three to six months; (3) graduated increases in height, with mastery of community terrain; and (4) walking in full-length legs, with mastery of community terrain.¹

Prior to committing to the treatment, Delmar's experience seeing Calhoun walk had already contributed to the first stage of his progress. The prosthetic care team also talked with Delmar about the inherent challenges of his treatment path, including the commitment required from both the care team and the patient. Delmar and his local prosthetist, Coles, traveled to Hanger's Oklahoma City facility, where Delmar proved to be an extremely motivated and physically fit patient. (See figure 1.)

Figure 2: Delmar’s shorties (right) were gradually weighted and lengthened to match his full-length legs (left).

Delmar spent two weeks in Oklahoma City. In the first week, he began stage two of the protocol when he was fitted with shorties—sockets with custom-made platform "feet" attached directly to the ends of the sockets. The feet were made of an approximately five in. by six in. polypropylene sheet with crepe soling and rounded corners. Delmar committed to an initial wear schedule of four to six hours per day and to using his wheelchair as little as possible. Delmar practiced walking in a wide variety of challenging terrains, including crowded areas, ramps, stairs, curbs, and grass slopes.

At the end of the first week, the team added manually locking knee joints to the shorties, which remained locked during ambulation and unlocked while Delmar drove his hand-control equipped car. The knees added two inches of height.

In the third week, Delmar participated in Carroll's bilateral transfemoral prosthetic-user workshop at the Amputee Coalition of America's National Conference. In the fourth week, Delmar returned home and continued diligently practicing in shorties in his community.

At the same time, he entered the third stage of the protocol, adding two to three inches to his leg length every two weeks, until they reached 17 inches from the bottoms of his sockets to the floor. His custom foot platforms were trimmed to ease navigation, eventually shrinking to approximately four in. square.

Figure 3: Having mastered community ambulation on shorties, Delmar now walks on full-length legs.

Delmar also wanted to ensure that his interface design and physical strength were sufficient to suspend the heavier, full-length microprocessor controlled legs he hoped to wear. He began adding ankle weights on the foreshortened prostheses, adding one to two lb. per month until he worked up to 7.5 lb. per side. (See figure 2, right.) His wear schedule increased to all-day use, a first in his prosthetics experience, which gave him hope that he would be able achieve his goal.

After approximately five months, Delmar met with Carroll again to enter the fourth stage of the protocol, being fitted with his C-Legs. He is currently in the process of mastering community ambulation at full height. (See figure 3.)

Outcome

In the month between Delmar's being fitted with full-length legs and the completion of this article, he has reported good progress in ambulation at full height, and secure socket suspension with the new interface.

Delmar's story is proof that it's never too late for people with bilateral transfemoral amputations to reevaluate their ability to walk—even after previous prosthetic failures. By systematically mastering each stage of the protocol, he was able to take full advantage of his custom suspension technology. Important factors in his success included inspiration from peers, a commitment to and full mastery of shortie walking using the custom feet, and gradual increases in height before graduation to full-length legs. Delmar remains highly motivated in this process. His commitment to reduce or eliminate wheelchair use was a critical part of his success.

Acknowledgements

Kevin Carroll, MS, CP, FAAOP, is vice president of prosthetics for Hanger Prosthetics & Orthotics.

Bobby Coles, CP, serves at the Hanger facility in Pittsburgh, Pennsylvania.

Randy Richardson, RPA, provides education to bilateral patients at Hanger's Oklahoma City facility and serves as a visual media director for Hanger.

Chad Simpson, BOCP, is chief prosthetist at Hanger's Oklahoma City facility, and regularly partners with Carroll to solve challenging prosthetic socket-fitting issues.

Jim Delmar is a Vietnam veteran and a graphic designer for Westinghouse Electric.

Reference

Carroll K, Richardson R. Improving Outcomes for Bilateral Transfemoral Amputees: A Graduated Approach to Prosthetic Success. The Academy Today. March 2009.

Case Study 2: Bypassing the Residual Limb to Avoid Triggering RSD/CRPS Type 1 Pain

Reflex Sympathetic Dystrophy (RSD), which in 1993 was renamed Complex Regional Pain Syndrome (CRPS) Type 1, is a chronic idiopathic disorder, which, unlike most neuropathies, is not secondary to demonstrable nerve lesions. It is characterized by severe pain, tissue swelling, and skin changes to an affected area. It may occur secondary to injury or surgery though in some cases it has presented with no known injury to the affected site.¹

History

Mark, a 49-year-old single father whose non-dominant left arm was amputated transhumerally secondary to traumatic injury, was referred to Jack Uellendahl, CPO, Hanger Prosthetics & Orthotics, for prosthetic fitting after rejecting a previous prosthesis due to RSD.

In May 1999, Mark was working as a lineman on high-powered overhead lines. He was using a hydraulic crimping tool to crimp an end-connection on a power line when a pinhole leak opened in the tool's hydraulic line, shooting hydraulic fluid at 10,000 lb. per square inch onto Mark's arm, penetrating the skin in several places and injecting hydraulic fluid into the arm. He was thrown backward by the pressure and sustained fractures of cervical vertebrae C3–C5. This caused neurological deficit leading to some weakness in the lower limbs.

Secondary to the original injury and prior to the amputation, Mark also had developed CRPS Type 1, with intense pain throughout the left arm and entire left shoulder area. Touch of any kind on the residual limb is highly painful, and he has stated that his sensitivity is such that if he walks in front of a fan, the movement of air on his bare limb will significantly increase his pain. He describes the sensation in his chest area as "like having a spike through my chest." Cold weather exacerbates his pain, and Mark, who resides in the Rocky Mountain area, typically wears four layers of clothing on his upper body to warm the affected area. He has used a variety of pain-control measures, including implanted functional electrical stimulation (FES) and medication, with no resolution.

Limb-salvage procedures on the left arm continued through 2007, when the appearance of necrotizing skin on the arm forced amputation slightly above the elbow in July 2007.

Mark's compensatory overuse of his sound-side hand has also caused carpal tunnel syndrome in it, which has lead to difficulties in performing ADLs.

Development of a Prosthetic Solution

Figure 1: Mark’s prosthesis and interface make no contact with his painful areas.

Figure 2: Rear view of Mark’s interface.

In July 2008, Mark's first prosthetist introduced a roll-on liner, which Mark could tolerate for approximately two hours per session. The prosthetist then developed a lightweight endoskeletal prosthesis with a hook terminal device. Mark could only tolerate wearing it for about 30 minutes once every third day, and the shoulder movement involved in pulling the cable of the body-powered hook caused intolerable pain.

Considering the intensity of Mark's pain at that time and its intensification in cold weather, Mark and his prosthetics team decided to pause his prosthetic care through the winter of 2009, hoping that Mark's pain would subside. In the spring of 2009, Mark met with Uellendahl, who established that fitting a conventional socket would still fail. Mark's sound-side carpal tunnel syndrome was also progressing, and his treatment team stated that a manually positioned device with a gripping terminal device, akin to a portable vise, would be ideal for preventing Mark from developing further overuse injury. Mark contributed that a device that "fit like a tool belt" might be tolerable to wear. Uellendahl decided to reject the anthropomorphic model and create an interface that would not come into contact with Mark's residual limb or painful areas at all, basing the design on shoulder-disarticulation prostheses. (See figures 1 and 2.)

Figure 3: Electronic touch pads accessible from the sound side control the electric hook.

The lightweight prosthesis includes a passively positioned elbow located at anatomical height that can rotate at the humeral section, lock, unlock, flex, and extend. Its electric hook provides very firm force and is controlled by touch pads mounted to the forearm for control by the sound-side hand. (See figure 3.)