Zancolli lasso procedure for correction of paralytic claw hands

To evaluate the outcome of 20 claw hands corrected with the Zancolli lasso procedure.

20 patients aged 7 to 48 (mean, 28) years with claw hand deformity for a mean of 33.3 months secondary to leprosy (n=17), traumatic ulnar nerve injury (n=2), or tardy ulnar nerve palsy (n=1) underwent the Zancolli lasso procedure, in which the flexor digitorum superficialis (FDS) of the middle finger was divided in to 4 slips (one for each finger) and reattached to itself after passing through the proximal pulley. Deformity, power, movement, and function of the hands were evaluated before and after surgery.

The mean duration of surgery was 58.4 (range, 50-107) minutes. The mean duration of follow-up was 18 (range, 12-24) months. Deformity correction was good in 15 patients, fair in 3, and poor in 2. The mean angle improvement was maximum in the little finger, followed by the ring, index, and middle fingers. The transverse metacarpal arch (compared with the normal hand) was increased/reversed in 7 patients and decreased in 13 patients. The grip and pinch strength increased in 13 patients, remained unchanged in 6, and decreased in one. Motion and function of the hand was good in 12 patients, fair in 6, and poor in 2. One patient developed swan neck deformity in the little finger owing to suture tension of the transferred slip, and another had paraesthesia over the index finger. They underwent reoperation using the FDS of the ring finger; no sensory or motor recovery was achieved.

The Zancolli lasso procedure is easy to perform and does not require extensive postoperative training. It restores synchronous finger flexion and spares other superficialis tendons, thus avoiding swan neck deformity of the fingers.