THENAR AND HYPOTHENAR REVISION IN DEEP BURNS OF THE HANDS

Ann. Medit. Burns Club - vol. VIII - n. 2 - June 1995

THENAR AND HYPOTHENAR REVISION IN DEEP BURNS OF THE HANDS

Birdid A.

Department of Plastic Surgery and Burns, Medical Center, Ljubliana, Slovenia

RESUME. Full recovery of the burned hand is often prevented as a result of fibrosis of the skin and subcutaneous tissue and of fibrosis of the muscles. This fibrosis is caused by inadequate blood supply. It is therefore important to ensure adequate perfusion of the burned hand. During the first 6-12 hours post-bum release incisions should be performed in order to open the fascial spaces, and necrotic tissue must be excised. The thenar and hypothenar muscles mus.t be revised and any muscle fibres showing signs of devitalization excised. Appropriate physiotherapy will restore reasonable functionality.

In deep burns of the hands the results of treatment are generally poor because of the severity of the thermal trauma. The stiff and painful hand is due partly to fibrosis of the skin and subcutaneous tissue and partly to fibrosis of the muscles, in both cases due to inadequate blood supply.
To follow the development of impaired blood supply in deep burns of the hands and forearms it is necessary to assess:

- tenseness of the extremity
- ability to move the fingers
- deep muscle pain
- paraesthesia
- distal pulses (Doppler)

All these criteria are subjective and detectable pulses do not guaranteee adequate perfusion in the intrinsic muscles. Restoration of the circulation and protection from infection can be adequately achieved by immediate surgery during the resuscitation period, i.e. the first 6-12 hours.

The following options are open to the surgeon:
1. Release incisions on the upper extremity and over the thenar, hypothenar and dorsum of the hand: this procedure opens the fascial spaces and is followed by excision of all burned tissue.
2. Immediate excision of all necrotic tissue and revision of the thenar and hypothenar: this is the most efficient way to ensure an adequate blood supply.
3. Unfortunately, patients do not always arrive immediately after the accident. They are frequently sent on from other hospitals on the second or third day post-burn. The final depth of the burned skin is established around the third day and the consequence of ischaemia is necrosis of the muscles. During the operation for excision of burned tissue, the thenar and hypothenar muscles must be revised. Muscles fibres showing signs of devitalization have to be excised in order to preserve viable fibres from infection and further damage.

Such severely damaged hands can of course be reconstructed by means of grafts and flaps. Muscles however cannot be restored. In my clinical experience not all the muscle fibres are damaged and with appropriate physiotherapy reasonable functional results can be obtained.

RESUME. La guérison complète de la main brûlée est souvent difficile à cause de la fibrose de la peau et du tissu sous-cutané et de la fibrose des muscles, fibrose causée par la provision inadéquate de sang. Il est donc important d'assurer une perfusion adéquate de la main brûlée. Pendant les premières 6-12 heures après la brûlure il faudrait pratiquer des incisions de décompression pour ouvrir les espaces fasciaux, et exciser le tissu nécrotique. Les muscles thénariens et hypothénariens doivent être révisés et il faut exciser tous les fibres qui montrent des signes de dévitalisation. Une physiothérapie appropriée restaurera un niveau raisonnable de fonctionnalité.

BIBLIOGRAPHY

Kingsley N.W., Stein J.M., Levenson S.M.: Measuring tissue pressure to assess the severity of bum induced ischemia. Plast. Reconstr.Surg., 63: 404-8, 1979.
Salisbury R.E., McKeel D.W., Mason A.D.: Ischemic necrosis of intrinsic muscles of the hand after thermal injuries. Bone & Joint Surg., 56A: 1701-7.