Active tendon implants in flexor tendon reconstruction.

Forty-five active flexor tendon implants were evaluated after placement in scarred tendon beds of digits II through V. The implant is constructed of silicone rubber with a Dacron core, terminating in a loop proximally and a metal plate distally. Modification of the implant during the period of study has improved its reliability and longevity. The improvement in total active motion (TAM) averaged 72 degrees during implant functioning (stage I) in a group of digits that before operation were classified as 78% Boyes grade 5 (salvage). Complication rate during stage I was 11% (5 out of 45). Of the 27 digits evaluated after implant replacement by tendon autograft (stage II), there was an overall improvement in 62 degrees total active motion with 70% of digits being Boyes grade 5. Many of the complications were believed to be avoidable with experience. This study demonstrates the feasibility of an active tendon implant and the possibility of a permanent prosthesis.

Ganglion cysts and carpal tunnel syndrome.

We review 12 cases of ganglion cyst with carpal tunnel syndrome in 11 patients seen at the Hand Rehabilitation Center. Mean age was 42 years (range, 28 to 60 years). One half of the cysts were associated with direct trauma, usually with wrist hyperextension. Symptoms usually developed after the appearance or sudden growth of the cyst. Motor conduction or distal sensory latency was abnormal in seven of eight studied cases. Tinel's sign on tapping the cyst may be pathognomonic for this syndrome. Cyst removal and incision of the flexor retinaculum relieved the symptoms in 11 cases. The other case had total resolution after spontaneous cyst rupture. This syndrome is successfully treated with cyst decompression with release of the carpal canal and has an excellent prognosis. To our knowledge this represents the largest operative series of carpal tunnel syndrome and ganglion cyst.

The treatment of intercostal-brachial neuromas by posterior intercostal neurectomies. A case report.

The development of sensory neuromas in a postoperative field is a recognized and undesirable complication. Neuroma formation can impair patient cooperation and postoperative function. Treatment efforts are frequently unrewarding and may contribute to the patient's frustration. Intercostal-brachial neuromas which develop following first rib resections are representative of this problem. Posterior intercostal neurectomy may provide an alternative treatment modality.

Nerve injury complications. Management of neurogenic pain syndromes.

Postural brachial plexus compression neuropathy occurs more frequently than usually realized. The cause is multifactorial with certain predisposing anatomic and congenital factors that are not uncommon. An inciting event is required to cause a clinically significant syndrome. The event can be a specific traumatic episode or cumulative trauma leading to an adoption of a guarding posture, which results in a self-perpetuating cycle and brachial plexus nerve compression. The diagnosis and management may be complicated by concurrent vascular compression, concurrent reflex sympathetic dystrophy, and associated inflammatory musculotendinous conditions. Diagnosis relies on the appreciation of a peculiar symptom complex of pain and paresthesias. The important clinical signs are a supraclavicular Tinel's sign and a positive stress abduction test. Treatment includes exercises, patient education, and behavior modification. However, misdiagnosis can lead to inappropriate treatment, such as unnecessary carpal and cubital tunnel releases. Operative treatment is reserved for those severe cases that are resistant to extended and intense physical therapy. The preferred surgical technique involves an anterior, supraclavicular approach allowing for complete visualization and release of intrinsic and extrinsic nerve compression. Awareness is the key to making the diagnosis, and successful treatment requires a multidisciplinary approach. It is generally accepted that injuries to peripheral nerves result in serious losses of function. Paresthesias and motor weakness cause immediate functional limitation, and place the hand at risk for further injury. The system has little regenerative capacity, and the chance for recovery is poor even under the best circumstances. Therefore the treatment of acute nerve injuries can be difficult and frustrating.(ABSTRACT TRUNCATED AT 250 WORDS)

Autogenous sural nerve grafts: a harvesting technique.

Sural nerve grafts have applicability in many facets of reconstructive surgery. A harvesting technique is described which utilizes a tendon stripper introduced through a single distal incision. This method provides adequate length of autogenous graft material without significant difficulty or morbidity.

The effect of vincular injury on the results of flexor tendon surgery in zone 2.

From a consecutive series of 82 fingers (69 patients) that sustained flexor tendon lacerations in zone 2, 47 fingers (39 patients) had the status of the vincular system determined during primary repair. The vincula were intact in 22 fingers and not intact in 25. Total active motion (TAM) after rehabilitation and before a reconstructive procedure, such as repair of a rupture, tenolysis, or grafting of a tendon, was the end point of the study. The overall mean TAM was 196 degrees. The mean TAM was 222 degrees for fingers with intact vincula and 176 degrees for fingers with vincula not intact (p less than 0.01). There were no statistical differences between the two groups regarding surgical results when the number of tendons injured per finger and sheath closure were analyzed. This study suggests that the integrity of the vincular system is a determinant of end result TAM and flexor tendon lacerations in zone 2.

The pseudosynovial sheath--its characteristics in a primate model.

The characteristics and long-term fate of the pseudosynovial sheath formed in response to a gliding tendon implant were examined. A primate model was chosen to reproduce the human clinical situation. Hunter passive gliding implants were implanted in 32 digits of eight Macque monkeys. Surgical syndactylism was created to the adjacent active digits to provide passive range of motion of the digits. No implanted digits demonstrated progressive flexion contractures. Radiographs revealed passive excursion of the implants of an average of 2.5 cm. Biopsies were taken at various time intervals and locations for histological examination. The pseudosynovial sheath has three descriptive layers: an intima, media, and adventitia. This sheath becomes mature and stable at 8 weeks. The intima cells contain a glycosaminoglycan substance and have a secretory capacity. The media cells have large amounts of collagen and provide structural and vascular support. The adventitia is a highly vascular structure composed of loose fibrous tissues that demonstrates clefts that may represent gliding planes. The pseudosynovial sheath was found to be a morphologically stable structure that showed no propensity for longitudinal contracture. The sheath appears to have the characteristics necessary to provide a good bed for a tendon graft.

Experimental vascularized total joint autografts--a primate study.

Autogenous vascularized and nonvascularized total joint transfers were studied in the hands of Macaca fascicularis monkeys. Nine second toe proximal interphalangeal joints were transferred as a vascularized free graft to the hand, and the excised finger joints were transferred to the foot as a nonvascularized free graft. The grafts were examined clinically and histopathologically at 16 weeks to 10 months. Two of the nonvascularized free grafts were amputated because of infection and necrosis. Three had chronic infections. The four surviving nonvascularized grafts demonstrated necrosis of the hyaline cartilage and degenerative changes. Of the nine vascularized joints, one developed a wound infection that required amputation, another failed at 2 weeks because of wound dehiscence, and the remaining seven survived with preservation of the hyaline articular surfaces. The experimental technique was designed to be easily applied to clinical use. A skin island is provided as a "patency/viability monitor." The extensor mechanism is included in the graft for early function.

Comminuted fractures of the radial head. The role of silicone-implant replacement arthroplasty.

Radial head resection is the accepted treatment of comminuted radial-head fractures in adults, but the results are not always satisfactory. This study examines the results of silicone replacement arthroplasty of the radial head in acute fractures and as a salvage procedure after failed resections of the radial head. The first group of patients was evaluated both before and after silicone replacement arthroplasty had been done as a salvage procedure following a previous radial head fracture. This group comprised twelve patients with an average follow-up of 3.8 years. Improvement was found in a number of parameters, including supination and grip strength. The second group of patients had had a primary silicone replacement arthroplasty following a comminuted radial-head fracture. This group was composed of six patients with an average follow-up of 3.6 years. The radial head implant was found to provide a spacer effect that maintained good radiocapitellar contact and prevented radial shortening. Silicone replacement arthroplasty has a role as a useful, safe, and reliable alternative in the treatment of comminuted radial-head fractures in adults and as a salvage procedure in patients with failed radial-head resections. This is especially true in young, active individuals, who were found to be at the greatest risk of failure after radial head resection alone. This was attributed to greater demands being placed on the involved extremity.

Tendon implants: primary and secondary usage.

The staged tendon grafting technique has definite advantages in reconstructive hand surgery. The benefits are realized in the more severely injured flexor tendon systems (Boyes' grades 2 to 4). The results obtained in these cases compare favorably with those achieved by primary tendon grafting in less severe grade 1 cases. This is made possible for the following two reasons: First, the inert nature of the implant allows numerous auxiliary procedures to be done at stage I, such as digital neurography, osteotomy, capsulotomy, scar resection, and pulley reconstruction. This can be done without fear of profuse formation of adhesions. Second, the passive gliding of the implant forms a pseudosynovial sheath, which provides a nutritive and physiologic bed for the autograft tendon at stage II. The operative technique has been presented and the postoperative care has been outlined. It cannot be overstressed that a good working relationship between the surgeon, hand therapist, and patient is of paramount importance to the success of the final result. Work on a prototype active gliding tendon prosthesis is described with details of the concepts and biomaterials involved in its development.