A man was wounded, December 21, 1914, by a bullet which entered about the middle of the spinous process of the left scapula and was extracted a few days later from the posterior border of the sternocleidomastoid muscle, two finger-breadths from the left clavicle, that is, at about Erb’s point. The left upper extremity was inert for ten days, but then began to move again, although extension and flexion of the fingers did not begin at once.
October, 1915, movements were normal, except those of extension of the forearm, due to contracture of the supinator longus muscle, a contracture that had developed about three weeks after the wound and stood out along the external border of the forearm, almost suggesting a musculotendinous retraction. There was a palpable, hard callus of a fractured rib, presumably a cause of the permanent irritation of the supinator longus, being precisely at the point where lesions usually produce superior brachial plexus palsy.
Why should the supinator longus alone of the Duchenne-Erb group be affected? Perhaps a single root was involved in the irritative lesion. The biceps showed also a partial R. D. The deltoid was normal electrically and in contraction.
The treatment planned for this case of isolated contracture of the supinator longus was surgical operation of the irritative focus. According to Léri and Roger, it is sometimes dangerous to use such measures as massage and electric baths for a paralyzed limb, since the massage or electricity excite not only the affected muscles, but also the other sound muscles,—muscles that are already more powerful than the paralyzed muscles and may go into antagonistic contracture. Even in limited galvanization, it is desirable to work with weak currents, so as not to diffuse the current into non-paralyzed muscles. In case of radial or sciatic paralysis, apparatus permitting the extremities to rest without over-action of the muscles antagonistic to the paralyzed ones may well be applied.
We here deal with a case, therefore, which looked purely functional, but in which careful examination and X-ray served to show an organic focus of irritation.
Re nerve concussion, Tubby offers the following definition: Nerve concussion is damage to a nerve trunk without actual destruction of the axis cylinders. The damage may consist of an effusion of blood between the nerve fibres following compression of a nerve against the bone by rapid passage of a foreign body near the nerve. Sometimes, however, the lesion which causes damage to the nerve trunk without actual destruction to the axis cylinders is nothing more than a temporary anemia or hyperemia. In most instances, both motor and sensory function are together interfered with, but in the case of large nerve trunks, e.g., the popliteal, there may be a separate concussion of motor or sensory bundles.
Contusion may effect a sort of STUPEFACTION OF MUSCLE and paralyze it by a non-psychic process: The SYNERGY in contraction of biceps and supinator longus is thus SPLIT. Biceps restored to synergy with the supinator by massage and faradism.
Case 253. (Tinel, June, 1917.)
A man was wounded at about the middle of his biceps and three weeks later was found to be able to flex the forearm only by means of the supinator longus. The biceps remained absolutely flaccid and soft, so that the diagnosis of a lesion of the musculocutaneous nerve (unlikely as this seemed on account of the low site of the wound) was entertained.