A method of enhancing regeneration of conventionally repaired peripheral nerves.

The effect of axoplasmic fluid injection on regeneration of conventionally repaired nerve was studied. Twenty New Zealand rabbits were studied in two experimental groups: immediate nerve repair (Group 1A, no axoplasm; Group 1B, axoplasm injection) and delayed nerve repair (Group 2A, no axoplasm; Group 2B, axoplasm injection group). A total of 40 sciatic nerve repairs were performed. After epineurial nerve repair, axoplasmic fluid collected from the proximal and distal nerve stumps was injected under epineurium proximally and distally to the anastomotic site. In the two control groups (immediate nerve repair and delayed nerve repair, both without axoplasm), 0.9% saline was injected in a similar way. Nerve regeneration was assessed by measuring hair and nail growth, plantar and dorsal foot temperature, muscle atrophy, and the toe spread test. In the 3- and 6-month follow-up periods, nerve samples were taken for histological evaluation. Specimens were stained with toluidine blue, and 50% of the nerve cross-section area was counted from microphotographic reconstructions. After immediate repair in Group 1, axoplasmic fluid-treated animals showed a 27% increase in the number of myelinated axons at 3 months when compared with saline-treated controls (3,768 vs. 2,962 +/- 1,921 SD). After delayed repair in Group 2, a 32% increase in myelination axon counts was detected at 3 months in axoplasm-treated animals compared with saline-injected controls (1,040 +/- 684 SD vs. 786 +/- 389 SD). In addition, a positive toe spread test result was seen at 6 months in the axoplasmic fluid-treated animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevention and emergency field management of venomous snakebites during military exercises.

Summer exercises in the continental United States bring many military personnel in contact with our four types of indigenous venomous snakes. Personnel with a knowledge of these snakes, their habits, and habitat, and who exercise common sense are much less likely to fall victim to a venomous bite. When a bite does occur, timely and appropriate first aid can help to reduce the sequelae of an envenomation. Military medical personnel should be prepared to discuss snakebite prevention and field management with all personnel taking to the field this summer.

Animal bite wounds.

A wide variety of bite wounds are discussed, from dogs and cats to marine animals and snakes. The type of wound each animal can inflict is shown, along with a thorough description of the proper treatment techniques.

Snakebites. Guidelines for practical management.

Snakebite treatment remains a controversial subject, even among experts. Nevertheless, all physicians need to be aware of current concepts in snakebite management, because incorrect treatment could be detrimental or even fatal. This article discusses the mechanisms of envenomation and presents guidelines for snakebite prevention, emergency field therapy, and emergency department therapy.

Prevention of extensor lag after indicis proprius tendon transfer.

An experiment on fresh cadaver hands showed that a longitudinal incision of the hood did not affect index extension when traction was made on the common extensor tendon, but that excision of a portion of the hood containing the indicis proprius caused an extensor lag. The lag was eliminated by repair of the hood, providing that the closure was not too tight to prevent normal excursion of the hood. These findings were correlated with findings in patients who had undergone indicis proprius tendon transfer. Extensor lag after indicis proprius transfer is not caused by removal of the force of the tendon per se, but by factors which cause either disruption of normal hood function or tethering of its normal excursion.

Burn syndactyly.

When the entire digital web space has been destroyed by burn scarring and there is a contracture of the volar aspect of the web as well as the dorsum, Z-plasties and skin grafts alone seldom produce a satisfactory web space. During the past 3 years, for the release of 46 contracted web spaces in 20 burned patients, we have turned a rectangular flap from the dorsal surface of the web through into an inverted-T incision in the palm. The adjacent sides of the defects have been skin grafted. In all these patients, we obtained satisfactory release of the contracture and restoration of the web space.

Ski pole thumb injury.

Disabling injuries can occur in the area of the MP joint of the thumb when a skier falls against the planted ski pole while holding the ski strap in the usual fashion. This is presently the most common ski injury of the upper extremity. It is important to determine if instability has resulted, because there may be disruption of the ulnar aspect of joint capsule as well as of the extensoradductor hood mechanism. If this has occurred, it is immediately to prevent the development of the chronic "gamekeeper's thumb."

Carpal tunnel syndrome caused by hand injuries.

Although carpal tunnel syndrome associated with injury to the wrist is common, it is possible to overlook symptoms of median nerve compression caused by an ascending tenosynovitis secondary to trauma distal to the wrist. One should look for these symptoms in such patients who complain of pain and weakness of the hand, and release the carpal tunnel if nerve compression is suspected.