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.

Mechanoreceptors in the palmar wrist ligaments.

Three palmar wrist ligaments from fresh human cadavers were dissected from the proximal to the distal insertions and stained to identify the mechanoreceptors. Golgi organs, Pacinian corpuscles, Ruffini endings and free nerve endings were present in all three ligaments. In the radial collateral and radiolunate ligaments they were found in increased density towards the proximal and distal insertions. A more uniform distribution was found in the radioscaphocapitate ligament which has attachments to three bones. The palmar wrist ligaments may have a significant sensory role in maintaining the stability of the wrist and in controlling its movement. Although technically difficult, the surgical repair of traumatic wrist defects should attempt to preserve the innervation of the ligaments, shown to be mainly near bony attachments. This may allow improvement in postoperative outcomes by preserving some proprioception. In some painful post-traumatic or degenerative conditions, however, denervation may be advantageous.

Complex femur fractures: treatment with the Wagner external fixation device or the Grosse-Kempf interlocking nail.

One hundred complex femur fractures were treated with the Grosse-Kempf interlocking nail and 35 were treated with the Wagner external fixation device. Retrospectively, we analyzed the results in the two groups to determine specific indications for the future use of these nails. The Grosse-Kempf nail, although a technically demanding procedure, achieved excellent overall end results in comminuted closed fractures, and in Type I, Type II, and some Type III open fractures after appropriate wound care. We found that the Wagner apparatus was a simple, easy device for obtaining initial fracture stabilization in contaminated Type III-B and Type III-C open fractures. It does, however, require substantial postoperative care; four cases required secondary intramedullary fixation. We found a high infection rate with secondary reamed intramedullary nailing after initial stabilization with the external fixator.

Management of the upper extremity in traumatic tetraplegia.

The management of the upper extremity in traumatic tetraplegia is complex and extremely important for the rehabilitation of the patient. The evolution of present management is reviewed. The evaluation and classification of the tetraplegic patient is discussed with general recommendations for treatment.

Muscular coactivation. The role of the antagonist musculature in maintaining knee stability.

The objective of this study was to quantify the coactivation patterns of the knee flexor and extensor muscles as part of continued efforts to identify the role of the antagonist muscles in maintaining joint stability. The simultaneous EMG from the flexor and extensor muscles of the knee were recorded during maximal effort, slow isokinetic contractions (15 deg/sec) on the plane parallel to the ground to eliminate the effect of gravity. The processed EMG from the antagonist muscle was normalized with respect to its EMG as agonist at maximal effort for each joint angle. The plots of normalized antagonist EMG versus joint angle for each muscle group were shown to relate inversely to their moment arm variations over the joint range of motion. Additional calculations demonstrated that the antagonist exerts nearly constant opposing torque throughout joint range of motion. Comparison of data recorded from normal healthy subjects with that of high performance athletes with hypertrophied quadriceps demonstrated strong inhibitory effects on the hamstrings coactivations. Athletes who routinely exercise their hamstrings, however, had a coactivation response similar to that of normal subjects. We concluded that coactivation of the antagonist is necessary to aid the ligaments in maintaining joint stability, equalizing the articular surface pressure distribution, and regulating the joint's mechanical impedance. The reduced coactivation pattern of the unexercised antagonist to a hypertrophied muscle increases the risk of ligamentous damage, as well as demonstrates the adaptive properties of the antagonist muscle in response to exercise. It was also concluded that reduced risk of knee injuries in high performance athletes with muscular imbalance could result from complementary resistive exercise of the antagonist muscle.

Bone block transfer of coracoacromial ligament in acromioclavicular injury.

A bone block transfer of coracoacromial ligament into the medullary canal of the clavicle for Grade III acromioclavicular injury was developed in an attempt to prevent occasional pullout of the ligament in the procedure described by Weaver and Dunn. Fifteen consecutive cases (12 acute, three chronic) with Grade III acromioclavicular injury were treated by this method. All but one patient regained painless full range of shoulder motion. All patients returned to previous activity. Failure of coracoclavicular reconstruction occurred in one case. Asymptomatic focal myositis ossificans developed in four cases with no functional deficit.

Intravenous reserpine for treatment of reflex sympathetic dystrophy.

The efficacy of reserpine in relieving the pain of reflex sympathetic dystrophy was tested in 25 patients--21 with upper extremity and four with lower extremity involvement. Injection of the drug relieved the acute signs and symptoms in the upper extremity in 12 of 17 patients. Four patients with quiescent reflex sympathetic dystrophy of upper extremities had prophylactic injection at the time of reconstructive surgery; they had no flare of symptoms. Relief was obtained in the four cases of lower extremity dystrophy. Our patients had no significant side effects. The drug is confined to the extremity by a pneumatic tourniquet as used for intravenous regional anesthesia. After the extremity is exsanguinated and the cuff is inflated, 1 mg of reserpine diluted to 50 ml with normal saline is injected intravenously into the upper extremity. In the lower extremity, 2 mg of reserpine diluted to 100 ml is injected. The tourniquet is removed after 15 minutes. The procedure is safe and can be done in an office setting.

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.