Faculty Bibliography

It has recently been suggested that peripheral nerve or plexus blocks performed with the use of a nerve stimulator at low currents (<0.5 mA) may result in neurologic damage. We studied the infraclavicular nerve block, performed with the use of a nerve stimulator and an insulated needle, in a prospective evaluation of efficacy and safety. During a one-year period, 248 patients undergoing infraclavicular nerve block were evaluated for block success rate and incidence of neurologic complication. All blocks were performed with the use of a nerve stimulator and an insulated needle at < or =0.3 mA. Success rate was 94%, which increased to 96% with surgical infiltration of local anesthetic. There were no intraoperative or immediate postoperative complications noted. After one week, only one patient had a neurologic complaint, and this was surgically related, referable to surgery performed on the radial nerve. We conclude that infraclavicular nerve blocks performed at low currents (< or =0.3 mA) are safe and effective

PURPOSE: To determine the optimal tunnel placement positions for tendon graft reconstruction of chronic thumb metacarpophalangeal (MCP) ulnar collateral ligament injuries that would stabilize the joint while maintaining motion. METHODS: Four commonly used tunnel placement methods were simulated on a cadaveric model using fresh-frozen thumbs and a suture/screw construct. The methods were as follows: (1) triangular configuration with apex proximal, (2) triangular configuration with apex distal, (3) cruciate configuration, and (4) parallel configuration. Stability was tested by valgus loading at 0 degrees and 30 degrees , and range of motion was tested by loading the thumb tendons. Statistical analysis was performed by 1-way analysis of variance testing. RESULTS: Valgus load stability testing at 0 degrees and 30 degrees showed that all 4 reconstruction methods stabilized the MCP joint compared with the fully sectioned state. The amount of stability achieved was not significantly different between the 4 methods. Only the reconstruction method, however, with a triangular configuration with the apex proximal restored flexion/extension range of motion not significantly different from the intact state. The other 3 methods resulted in significantly decreased range of motion. CONCLUSIONS: The reconstruction tunnel positioning of triangular configuration with apex proximal stabilizes the thumb MCP joint while maintaining flexion/extension range of motion. We recommend this configuration for chronic MCP joint injuries in which the native ulnar collateral ligament is inadequate and tendon graft reconstruction is performed

A structured meta-analysis of the available literature was performed to evaluate the outcome of the treatment of displaced intra-articular fractures of the distal radius. A comprehensive search of Medline using the key words 'radius' and 'fracture' revealed over 4,000 articles. After limiting the search to clinical trials in English and excluding pediatric and geriatric age groups as well as biomechanical and animal studies, 615 abstracts were identified in the period from 1976 to May 1998. Thirty-one articles met the inclusion and exclusion criteria. These included two prospective randomized comparative trials, two non-randomized comparative trials, one half prospective case series and half historical control, and 27 papers on case series. Four papers dealt with external fixation versus closed reduction and cast treatment and one paper looked at open reduction internal fixation with or without additional external fixation. There was insufficient data to perform a scientific meta-analysis because of the poor quality of the studies and lack of a uniform method of outcome assessment. However, the data from the comparative trials showed that external fixation was favored over closed reduction and casting. Additionally, comparing the results of the case series showed that external fixation was superior to internal fixation

Three cases of rupture of a flexor tendon graft many years after surgery are presented. Two cases occurred 12 years after reconstruction and the third case occurred 21 years after reconstruction. Each rupture was intratendinous, just proximal to the flexor tendon sheath in 2 cases and at the proximal edge of the transverse carpal ligament in the third case. Active digital flexion was restored by transfer of the flexor digitorum superficialis from an adjacent finger to the distal tendon stump or by direct end-to-end repair of the rupture site reinforced with an onlay autogenous patch graft. Patients undergoing tendon grafting should be alerted to the possibility of rupture, even many years later

Radial neuropathy can have one of several clinical presentations, depending on the level of compression: high radial nerve palsy, PIN palsy, radial tunnel syndrome, and Wartenberg's syndrome. Elucidating the history and progression of symptoms with a physical examination directed at testing individual muscles will determine the approximate anatomic level of radial injury. Identification of a Tinel's sign will often locate the site of compression. Electrodiagnostic studies can confirm the diagnosis in a radial motor neuropathy, but are unreliable in radial tunnel syndrome and sensory radial nerve compression. A trial of nonsurgical treatment is warranted in all cases except those with progressive motor weakness or palsy. Patients who do not respond or continue to progress despite conservative treatment are candidates for surgical decompression

We performed an in vitro study using canine flexor tendons to compare the tensile properties of a suture technique for flexor tendon repair with the standard modified Kessler technique. The technique employs a central wire loop that connects the two transverse limbs of the modified Kessler suture. Both techniques were studied with and without a Lembert epitendinous stitch. The technique combined with an epitendinous suture provided the strongest resistance to gap formation, and its load at gap initiation was 100% greater than the load in tendons repaired with the modified Kessler and an epitendinous suture. Because of its increased resistance to gap formation, this suture technique may provide a safer margin for controlled early active motion after flexor tendon repair.

A fresh cadaver study of the effects of a variety of scaphoid stabilizations on wrist motions is reported. Scaphoid-trapezium-trapezoid stabilizations with the scaphoid in its normal anatomic position and the same stabilizations with the scaphoid in malposition, either vertical or horizontal in relation to the radius, were compared. Scaphoid-capitate stabilizations with the scaphoid in its normal position were also studied. With the scaphoid vertical, a scaphoid-trapezium-trapezoid stabilization resulted in greater loss of wrist flexion and ulnar deviation whereas, with the scaphoid horizontal, wrist extension and radial deviation were more severely affected than when the scaphoid was stabilized in its normal position. With the scaphoid in its anatomic position, both scaphoid-trapezium-trapezoid and scaphoid-capitate stabilizations resulted in similar patterns of wrist motion.

An Ilizarov apparatus was successfully used in the treatment of a six-year-old child with a radially deviated hand caused by congenital pseudoarthrosis of the distal radius after previous traditional surgery failed. The limb length was restored, the pseudoarthrosis healed, and the deviated hand corrected. A second child, five years old, with Poland's syndrome, had a 90 degrees flexion contracture of the wrist that was treated with the Ilizarov apparatus. The flexion contracture was gradually corrected. It seems that the Ilizarov apparatus can be an important tool in the treatment of complex limb deformities

Although arthrodesis of an arthritic proximal interphalangeal joint provides excellent relief of pain, it does so at the expense of mobility. Silicone rubber implant arthroplasty also provides predictable relief of pain and approximately 60 degrees of motion. Insertion of the implant through a dorsal extensor-splitting approach is preferred when a tendon reconstruction is necessary, as in cases of boutonniere deformity. If tendon reconstruction is not necessary, the lateral approach is an excellent alternative because it does not disturb the extensor mechanism and therefore permits earlier rehabilitation exercises. The following article outlines the dorsal and lateral techniques and postoperative rehabilitation of silicone rubber arthroplasty.