Endoscopic carpal-tunnel release in cadavera. An investigation of the results of twelve surgeons with this training model.

Endoscopic carpal-tunnel releases were performed, with use of the two-portal technique described by Chow, on twenty-four fresh or fresh-frozen wrist specimens from cadavera. Twelve surgeons were taught the technique in the cadaver model by an experienced colleague. Nine surgeons performed one endoscopic carpal-tunnel release; three performed three or more. Incomplete release of the transverse carpal ligament was noted in nine specimens (38 per cent). The percentage of incomplete releases was the same for both the surgeons who performed one endoscopic carpal-tunnel release and those who performed three or more. Complications occurred in four specimens (17 per cent) and included lacerations of an ulnar artery and a median nerve, partial laceration of a flexor tendon, and a fracture of the hook of the hamate. The observed complications and incomplete releases of the transverse carpal ligament in this training model emphasize the risks that may occur when a surgeon is first learning this procedure.

Complications of scaphoid silicone arthroplasty.

Between 1971 and 1982, thirty-three patients underwent scaphoid silicone arthroplasty, and twenty-three of them were available for review after an average of three years of follow-up. Radiographically, there was evidence of carpal collapse with a progressive decrease in carpal height and a progressive increase in the scapholunate angle in thirteen wrists. Subluxation of the spacer occurred in thirteen patients, and nine of them also had dislocation of the trapezial stem. Clinically, grip strength did not improve and wrist motion increased only slightly. There were complaints of pain associated with subluxation of the spacer in more than half of the patients. Ten patients, eight of whom had a subluxated spacer, underwent thirteen secondary surgical procedures.

Postoperative infection in a double-occupancy operating room. A prospective study of two thousand four hundred and fifty-eight procedures on the extremities.

The purposes of this study were to determine the rate of infection associated with elective outpatient operations on an extremity, performed in a double-occupancy operating room (one operating room designed to accommodate two separate operating teams), and to determine which factors influenced this rate. We evaluated the records of 2458 consecutive patients who had had such a procedure, performed by one of nine surgeons during a two and one-half-year period, and in whom the operative wound had been classified as clean (without a drain) or clean-contaminated (with a drain). The information regarding the factors associated with the operation and the operating-room environment was recorded for each patient at the time of the operation. Each wound was inspected periodically in the attending surgeon's office for at least thirty days postoperatively. Using definitions established by the Centers for Disease Control, the attending surgeon determined the presence of infection primarily by judging whether there was purulent drainage or whether erythema or swelling at the operative site was beyond that expected from the procedure. Of the 2458 patients, thirty-seven (1.5 per cent; 95 per cent confidence interval, 1.1 to 2.1 per cent) had infection of the operative wound. Only eight patients (0.3 per cent) had deep infection, with seven of the infections necessitating a reoperation. Infection developed in thirty of the 2311 clean wounds, a rate of 1.3 per cent (95 per cent confidence interval, 0.9 to 1.8 per cent), and in seven of the 147 clean-contaminated wounds, a rate of 4.8 per cent (95 per cent confidence interval, 2.3 to 9.5 per cent) (p = 0.001). No cross-contamination occurred between patients who had infection. The rate of infection was not related to the number of patients who were operated on in the same room at the same time. Logistic regression analysis, used to account for confounding factors, demonstrated a significant association between the classification of the wound (use of a drain) and a higher rate of infection (p = 0.006) as well as between the instillation of a topical steroid solution and a lower rate of infection (p = 0.04). It also demonstrated a significant difference, with respect to the rate of infection, among individual surgeons (p = 0.02).

Digit replantation in infants and young children: determinants of survival.

Thirty-three children under 34 months of age with 41 digits amputated over a 15-year period were reviewed. There were 3 primary amputations, 6 composite grafts, and 32 replantations. Twenty-one variables were evaluated for their influence on 4-week digit survival. The overall survival rate of 32 replanted digits was 69 percent. Favorable uncontrollable variables were clean-cut injury and body weight greater than 11 kg. Favorable controllable variables included more than one vein repaired, bone shortening, interosseous bone fixation, and vein grafting of arteries or veins. Forty-one percent of children required a blood transfusion. Children with trauma to more than one digit were most likely to be transfused (p < 0.05). The combination of prompt digit reperfusion after successful arterial repair and at least one successful venous anastomosis resulted in a 95 percent digit survival rate, significantly higher than the 0 percent survival of digits lacking one or the other of these features.

Radial nerve entrapment.

The radial nerve is frequently more involved in entrapment syndromes than the ulnar and median nerves. Common sites of compression are the juncture of the middle and distal third of the arm (especially with fractures of the humerus), just distal to the elbow (radial tunnel), and proximal to the wrist between the brachioradialis and extensor carpi radialis longus. Often in entrapment syndromes involving the radial nerve, the true diagnosis is not evident and is arrived at only by exclusion, which sometimes delays initiation of effective treatment. Radial tunnel syndrome is rare, but decompression when indicated, can provide relief. Radial sensory nerve entrapment in the forearm (distal third) does occur, but patients often respond to temporary thumb spica splinting.

The effect of caffeine on digital haemodynamics.

Caffeine has been shown to increase mean blood pressure, but studies documenting the effect of caffeine on digits are lacking. We evaluated the effect of caffeine on digital blood pressure and pulse volume in normal volunteers. In the first part of the study, 24 subjects were given water containing either 200 mg of caffeine or placebo. Bilateral brachial and middle finger digital pressures were measured at room temperature before ingestion and at 30 and 60 minutes after ingestion. In the second part of the study, pulse volume recordings (PVRs) were obtained in 24 subjects at the level of the distal phalanx of the middle finger of one hand immediately prior to beverage ingestion and at 10 minute intervals for 90 minutes. Differences in mean digital systolic pressure, digital/brachial index, or PVR amplitude between the control and caffeine groups were not statistically significant. The administration of caffeine was found not to alter the haemodynamics of digital blood flow or digital pressure in this population.

Silicone implants.

Infection has not been considered in this article with each individual implant. The incidence is low indeed. In the only publication concerned primarily with the topic of infection following silicone implant surgery, Millender et al. reviewed 2105 implants of varying kinds. There were ten infections, seven of which were with Staphylococcus aureus. The onset was remarkably late--17 days after surgery on average. In seven cases the implant had to be removed and the eventual result was good, being likened to that obtained after an excisional arthroplasty. Reviewing the complications that occur with the various implants, it becomes evident that there are three primary concerns--fracture, subluxation, and synovitis. Fracture occurs primarily in the wrist and the metacarpophalangeal implants. The incidence of fracture in the wrist implant is 8.6, 9.4, and 19.8 per cent, giving an average of the means of 12.6 per cent. In the metacarpophalangeal joint, the incidence with the Swanson design is variously 1.9, 26.2 and 21 per cent, the average of the means being 16.4 per cent. The Niebauer design is reported as having a fracture rate of 29.7 and 38 per cent, for an average of the means of 33.9 per cent. The somewhat lower incidence of fracture of the wrist implant is offset by the fact that, in contrast to the situation with the smaller joint, the fracture is almost always symptomatic, requiring treatment. Largely for this reason, silicone wrist arthroplasty is limited mainly to the rheumatoid patient, being little used for post-traumatic arthritis. Subluxation of implants occurs mainly with the carpal replacements. The incidence in independent reports are 56.5 and 50 per cent, for an average of the means of 53.3 per cent with the scaphoid; 20, 20, and 50 per cent for an average of the means of 30 per cent with the lunate; and 5.3, 10, 11.2, 29, and 32 per cent for an average of the means of 17.5 per cent with the trapezium. In the case of the trapezium, excision of a portion of the trapezoid, supplemented where necessary by ligament reconstruction to support the first metacarpal, appears to give the hope of lowering the incidence of subluxation to an acceptable level. With the lunate, preservation of an anterior shell may give satisfactory results but judgment should await longer term studies of larger groups. The scaphoid implant gives most cause for concern, both because the incidence is high and because the solutions offered have either failed or are too recent to judge and perhaps too radical to accept.(ABSTRACT TRUNCATED AT 400 WORDS)

Pulse volume recording.

Noninvasive studies, in general, and pulse volume recordings (PVRs), in particular, play important roles in diagnosis, planning, and monitoring of therapy for vascular disorders of the upper extremity. Essentially, PVR is a useful screening tool to show whether hemodynamically significant vascular disease has produced alterations of digital flow patterns. PVR also has a role in differentiating between vasospastic and vaso-occlusive disease, in evaluating cold sensitivity, in monitoring medical and surgical treatments, and as a research tool. This method also has its limitations, which must be appreciated, to place the true role of this very useful noninvasive modality in proper perspective.