This section is from the book "Applied Anatomy: The Construction Of The Human Body", by Gwilym G. Davis. Also available from Amazon: Applied anatomy: The construction of the human body.
Wounds of the hand, owing to the free blood supply, heal rapidly. An exception, however, is to be made in the case of the tendons. These frequently slough. If the tendons are divided they are to be immediately united with sutures, otherwise they retract into their sheaths.
If nerves are divided where they are large, as near the wrist, they should be sutured, because they are partly motor and supply the short muscles of the hand; but if the digital nerves are divided they need not be sutured as they are only sensory. The median nerve enters the palm to the radial side of the median line, and its position can be determined by following down the interval between the tendons of the palmaris longus and flexor carpi radialis muscles.
Bleeding from wounds of the hand is not infrequently troublesome. The deep arch may be injured in a wound about 2.5 cm. (1 in.) below the lower crease on the anterior surface of the wrist. Its position can also be approximately determined by feeling for the upper end of the first interosseous space on the dorsum of the hand and selecting a spot at a corresponding level on the palmar surface. It lies deep beneath the palmar fascia and flexor tendons and nerves, and necessitates too great a disturbance of the parts to expose it for ligation; hence, when wounded, bleeding from it is checked by packing the wound with antiseptic gauze. A curved line, convex downward, from the radial side of the pisiform bone to the web of the thumb, describes approximately the course of the superficial palmar arch. It lies immediately beneath the palmar fascia, and if it bleeds freely can be exposed by an incision and tied. The incision should preferably be a longitudinal one to avoid wounding the digital arteries and nerves. The superficial palmar arch lies superficial to the tendons and they should not be disturbed. The digital nerves come down beneath the palmar arch, so that they need not be wounded in ligating it. - As they reach the webs of the fingers the nerves become superficial to the arteries, and in the fingers they lie anterior and nearer the median line. The fingers are usually supplied with blood from the superficial palmar arch, and the digital arteries between the palmar arch and webs of the fingers may be quite large. Sometimes the fingers are supplied by large digital branches from the deep palmar arch, then those from the superficial will be correspondingly small.
In uniting the several ends of tendons the two ends of the same tendon should be joined and not the flexor sublimis joined to the profundus and vice versa.