Sven-Olof Abrahamsson

Carpal tunnel release. A prospective, randomized assessment of open and endoscopic methods.

To define the role of two-portal endoscopic carpal-tunnel release as a method for the treatment of compression of the median nerve at the wrist, a prospective, randomized, multicenter study was performed on 169 hands in 145 patients. Either open or endoscopic carpal-tunnel release was performed in all of the patients who had clinical signs and symptoms consistent with carpal tunnel syndrome, had not responded to or had refused non-operative management, and had had electrodiagnostic studies consistent with carpal tunnel syndrome. Follow-up evaluations were performed at twenty-one, forty-two, and eighty-four days. At the end of the follow-up period, both the open and endoscopic methods had resulted in high levels of achievement of the primary outcomes (relief of pain and paresthesias). The numbness and paresthesias were relieved in eighty (98 per cent) of eighty-two hands in the open-release group compared with seventy-seven (99 per cent) of seventy-eight hands in the endoscopic-release group. This parameter was not recorded for three hands in the open-release group or six hands in the endoscopic-release group. The satisfaction of the patients with the procedure, graded on a scale of 0 to 100 per cent, averaged 84 per cent in the open-release group compared with 89 per cent in the group that had had endoscopic release. We found no significant differences between the two groups with regard to the secondary quantitative-outcome measurements, including two-point discrimination, postoperative interstitial-pressure data for the carpal canal, Semmes-Weinstein monofilament testing, and motor strength. The open technique resulted in more tenderness of the scar than did the endoscopic method. Thirty-two (39 per cent) of eighty-two hands in the open-release group and fifty (64 per cent) of seventy-eight hands in the endoscopic-release group were not tender at eighty-four days. This parameter was not recorded for three hands in the open-release group and six hands in the endoscopic-release group. The open method also resulted in a longer interval until the patient could return to work (median, twenty-eight days, compared with fourteen days for the open-release and endoscopic-release groups). Four complications occurred in the endoscopic carpal-tunnel release group: one partial transection of the superficial palmar arch, one digital-nerve contusion, one ulnar-nerve neuropraxia, and one wound hematoma.(ABSTRACT TRUNCATED AT 400 WORDS)

Tendon repair-cellular activities in rabbit deep flexor tendons and surrounding synovial sheaths and the effects of hyaluronan : An experimental study in vivo and in vitro

One deep flexor tendon and its surrounding sheath of each hindpaw of 48 rabbits were transected and repaired in order to investigate the abilities of rabbit flexor tendons and synovial sheaths to synthesize DNA and matrix components during healing and to study the effects of hyaluronan (HA). After repair, HA or saline was injected between the tendon and the sheath. Short-term culture and labeling in vitro were used up to 6 weeks after surgery to determine synthesis of DNA, proteoglycan, collagen, and noncollagen protein. Within tendon repair sites, the rate of cell proliferation increased and reached a maximum 5 days after surgery; within repaired synovial sheaths, the rate immediately decreased. In the healing tendons, the rate of collagen synthesis decreased and the rate of noncollagen protein synthesis remained unchanged. The opposite results were found within the healing synovial sheaths. HA did not affect the rate of cell proliferation or matrix synthesis in healing tendons or surrounding sheaths. These results show that cellular activities differ between tendons and synovial sheaths during healing and that those activities may not be affected by HA.

Effects of hyaluronan on cell proliferation and collagen synthesis: A study of rabbit flexor tendons In vitro

Hyaluronan (HA), a high-molecular-weight polysaccharide, has been suggested to play a possible role during the early stages of healing of a variety of connective tissues and when topically applied to decrease the formation of adhesions following tendon surgery. As the mechanisms of HA actions are still being discussed, this study was designed to assess the effects of HA on cell proliferation and synthesis of matrix components of deep flexor tendons in a well-defined culture system. Cell proliferation, measured as the radioactive 3H-thymidine uptake by cultured segments of rabbit flexor tendons, was inhibited by the addition of HA to the culture medium. HA of molecular weight 0.5 x 10(6) inhibited the uptake significantly at concentrations within the range of 0.1-2.0 mg/mL, HA of molecular weight 1.6 x 10(6) at 0.5-2.0 mg/mL, and HA of molecular weight 3.6 x 10(6) at 1.0-2.0 mg/mL, as compared to matched control groups. At the concentration of 2 mg/mL, HA of the molecular weights of 0.5, 0.8, 1.6, and 3.6 x 10(6) equally inhibited cell proliferation. No effect on synthesis of matrix components, measured as the radioactive incorporation of 35S-sulfate, 3H-hydroxyproline, and 3H-proline by cultured segments of rabbit flexor tendons, was observed. These findings show that exogenously applied HA may act as a modulator of flexor tendon fibroblast proliferation, indicating a possible mechanism for antiadhesive effects following administration after flexor tendon surgery.

Functional splinting versus plaster cast for ruptures of the ulnar collateral ligament of the thumb : a prospective randomized study of 63 cases

In a prospective randomized study that included 63 consecutive thumbs with injuries of the ulnar collateral ligament of the metacarpophalangeal (MCP) joint of the thumb, plaster cast immobilization was compared with functional treatment with a splint. The splint allowed flexion and extension of the MCP joint, but prevented ulnar and radial deviation of the thumb. The study included both operated on and nonoperated on cases where surgery was performed only when the torn ligament was regarded as displaced. Of 40 thumbs treated nonsurgically, 21 were treated with a cast and 19 with a splint. Of 23 thumbs treated surgically, 10 were immobilized postoperatively in a plaster cast and 13 were treated with the splint. At the follow-up examination after 15 (11-41) months, there was no difference between the treatment groups as regards stability, range of motion, strength of the injured thumb, and length of sick leave. However, the patients considered the splint more comfortable than plaster cast immobilization. We conclude that immobilization of the thumb after a ligamentous injury with a movable splint is strongly preferred by the patients and that the functional results of this technique are equal to plaster cast immobilization after both surgical and nonsurgical treatment.

Cellular survival and proliferation in autogenous flexor tendon grafts

In order to investigate fibroblast survival and proliferation in autogenous flexor tendon grafts, hindlimb intrasynovial and extrasynovial donor tendons were placed within the synovial sheaths of the medial and lateral forepaw digits of 21 dogs (42 tendons) and treated with controlled early passive motion. Intravital histologic evaluations with confocal microscopy and biochemical determinations of total DNA content and DNA synthesis were carried out at 10 days, 3 weeks, and 6 weeks. Intravital staining of the extrasynovial tendon grafts demonstrated variable degrees of cellular necrosis at the earliest intervals followed by cellular repopulation with fibroblasts and neovascularization from surface vessels. In contrast, intrasynovial tendon grafts were populated predominantly by viable cells at each interval, with occasional patches of cell necrosis and fibroblast ingrowth. Total DNA content and DNA synthesis values in the intrasynovial donor tendons were significantly lower than those seen in the extrasynovial tendon grafts at each interval. Extrasynovial tendons appear to act as scaffolds, undergoing extensive cellular death followed by a rapid repair response. Findings that intrasynovial tendon fibroblasts survive the tendon grafting process suggest that the nutritional supplies and metabolic requirements of intrasynovial and extrasynovial donor tendons differ largely.

Rehabilitation after subcutaneous transposition of the ulnar nerve: Immediate versus delayed mobilization

We studied 36 patients who had clinical signs and symptoms consistent with cubital tunnel syndrome and in whom nonoperative management failed. These patients underwent anterior subcutaneous transposition of the ulnar nerve followed by either immediate (20 patients) or delayed (16 patients) mobilization. All patients were evaluated with an outcomes assessment questionnaire, and 35 of the 36 were given repeat physical examinations. After surgery, there were no significant differences between the two groups in pain relief, weakness, or patient satisfaction (71% of the immediate mobilization group and 74% of the delayed group) were satisfied. Secondary quantitative outcomes such as grip strength, lateral pinch, or two-point discrimination were also not significantly different between the groups. Both groups had a statistically significant improvement in first dorsal interosseous and adductor pollicis muscle strength. In the immediate mobilization group, however, patients returned to work and resumed activities of daily living earlier (median 1 month) than patients in the delayed mobilization group (median 2.75 months). Therefore, we conclude that anterior subcutaneous transposition provides a high degree of satisfaction and relief of symptoms regardless of when mobilization is initiated. However, immediately mobilizing the patient significantly influenced how early the patient returned to work and resumed activities of daily living.

Extopic bone after hip replacement: Excision and free fat transplants in four cases

In four patients ectopic bone formed after total hip replacement was replaced with free fat transplants. One year later the patients were free from pain, and hip flexion had increased by 60 degrees on average. Ectopic bone was completely absent in one patient, and markedly reduced in the remaining three patients. Bone scintigraphy was found to be a sensitive technique to reveal early ectopic bone formation. Fat transplantation seems to be a satisfactory complement in the treatment of ectopic bone.

Maintenance of the gliding surface of tendon autografts in dogs

To determine whether there are differences in the extent to which the superficial cellular layers remain viable and contribute to the healing process, extra- and intrasynovial hindlimb donor tendons of 12 dogs (24 tendons) were labeled with 3H-thymidine in vitro and transferred to the medial and lateral toes of the forepaw. After transplantation, the distribution and amounts of remaining labeled cells within the healing tendon grafts were determined at 1 and 3 weeks after surgery by scintillation countings and autoradiographic examinations. The two types of tendon grafts showed different turnover rates for the elimination of labeled DNA. At 1 week, 25 percent of labeled DNA remained in the extrasynovial grafts and 65 percent in the intrasynovial grafts. The two types of tendon grafts also showed different healing responses histologically. Autradiographic examinations showed that the majority of labeled cells were located in the periphery of the control tendons and that the numbers of labeled cells within the newly proliferated superficial areas of both types of tendon grafts decreased over time. These findings indicate that intrasynovial flexor tendons may possess improved prerequisites for superficial cellular survival and tendon gliding following autogenous tendon grafting.

Biomechanical effects of operative nerve mobilization and transposition in a canine ulnar nerve model

The purpose of this study was to evaluate the effects that operative mobilization and transposition of the ulnar nerve have on both neural excursion and mechanical properties. Twelve dogs underwent ulnar nerve transposition and postoperative casting. Four animals were killed at 3 weeks and four animals were killed at 6 weeks. Four animals had their casts removed at 3 weeks, were allowed to ambulate, and were killed at 6 weeks. Operated and contralateral control nerves were compared. Neural excursion was measured near the elbow and 12 cm proximally. The nerves were harvested and their mechanical properties determined. Repeated measures analysis of variance revealed significant differences in longitudinal excursion between control and experimental groups at both sites. Ultimate strain, ultimate strength, and modulus were significantly reduced in the experimental groups. No differences were seen in cross-sectional area or stiffness between control and experimental groups. Analysis revealed no independent effect of the rehabilitation method. Results of this study indicate that significant changes in neural excursion, ultimate strain, ultimate strength, and modulus occur following ulnar nerve mobilization and transposition and that these changes persist throughout the early postoperative period.

Wagner surface replacement of the hip: Three to six year follow-up

Forty-two Wagner surface replacements were followed prospectively for 4 (3-6) years. Fifteen hips required rearthroplasty, in 11 cases owing to loosening and in 2 cases because of fracture of the femoral neck.