Robert G Chuinard

Silicone-rubber interposition arthroplasty of the carpometacarpal joint of the thumb

Since 1969, a slightly modified silicone-rubber neurosurgical burr-hole cover has been used for a type of interposition arthroplasty of the carpometacarpal joint of the thumb. The short stem of the device fits into a hole burred into the distal surface of the trapezium. The flat surface of the device covers the distal surface of the trapezium. Forty-nine operations were done on 42 patients, 35 women and seven men. The age range of the patients was 34 years to 72 years, with an average of 55 years. The average follow-up time was 31 months. Forty results were rated as excellent. There were two failures due to breakage of the device, and in both cases the breakage was due to a technical error.

Tendon transfers for radial nerve palsy: Use of superficialis tendons for digital extension

Since 1959, 22 patients have had wrist extension restored by transfer of the pronator teres to the extensor carpi radialis longus and brevis, common finger extension by transfer of the superficialis of the long finger, independent thumb and index finger extension by transfer of the superficialis of the ring finger, and abduction of the thumb by transfer of the flexor carpi radialis at the wrist joint level. Twenty-one of 22 patients have been evaluated from 8 months to 15 years after operation, with an average follow-up of 4.5 years. By our new system of evaluation, there were 10 excellent results, six good results, five fair results, and all patients improved. Sixteen patients obtained full, independent thumb-index finger extension, three had fair function, and two obtained thumb-index extension by tenodesis of the transfer. This procedure allows full metacarpophalangeal extension independent of wrist position, provides thumb-index finger extension independent of the ulnar three digits, and maintains the dorsal-radial-to-volar-ulnar plane of functional motion of the wrist by retaining the flexor carpi ulnaris.

Mechanoreceptors in the human elbow ligaments.

The medial, annular, and lateral elbow ligaments from 6 fresh human cadavers were dissected from origin to insertion, stained, and examined with a light microscope to determine the existence of mechanoreceptors. It was shown that the anterior, posterior, and transverse medial ligaments as well as the annular and radial collateral ligaments were endowed with mechanoreceptors. The mechanoreceptors consisted of Golgi organs, Ruffini terminals, Pacinian corpuscles, and free nerve endings. The mechanoreceptors were distributed evenly throughout the annular and transverse medial ligament, but with increased density toward the origin and distal insertions in the radial, posterior, and anterior medial ligaments. It was concluded that the elbow ligaments may provide significant sensory function to the elbow joint, in addition to being its major mechanical restraints.

Two-stage superficialis tendon reconstruction in severely damaged fingers

In 16 fingers in 12 patients, where profundus tendon reconstruction was contraindicated due to soft tissue and distal joint changes, the superficialis tendon was reconstructed in two stages using a round silicone rod from the distal interphalangeal joint to the lumbrical level in the palm and profundus-superficialis tenorrhaphy as the first stage. The proximal end of the pedicled superficialis was used as the graft in the second stage. Fifteen fingers obtained a satisfactory result; one was a failure when the rod protruded through the skin. Two patients required a third surgical procedure: one a tenolysis at the superficialis-profundus junction, the other reattachment of the graft distally.

THE 'SUICIDE' WRIST: EPIDEMIOLOGIC STUDY OF THE INJURY

One hundred and ninety-one selfinflicted wrist lacerations in 148 different patients who presented to the Sacramento Medical Center Emergency Room from July, 1975, through June, 1977, are analyzed. One hundred and fifty-four (80.6%) involved the skin alone. Of the 37 lacerations with deep structure injury, 31 involved the palmaris longus. Only four of these were isolated injuries, and if this tendon is cut, there is an 87.1% association with a variety of other lacerated structures.

Distraction pinning for radial metaphysis fractures.

Comminuted fractures of the distal radial metaphysis are inherently unstable. Reduction can be obtained utilizing traction, and then the fracture stabilized by placing pins proximal and distal to the fracture and incorporating these pins in a short-arm cast. The results of 36 patients treated in this manner were analyzed. An excellent result was achieved in 78% of the cases.