Extensor hood injuries in elite boxers: injury characteristics, surgical technique and outcomes

Abstract

We describe our experience of managing extensor hood injuries in boxers (57 fingers). The diagnosis was mostly clinical, with imaging only if the diagnosis was equivocal. The middle (61%) and index (26%) digits were most frequently injured. On exploration, 26% had no hood tear, however all required tenolysis from the adherent capsule. Of 42 hood tears, 15 were central splits between adjacent extensor tendons in the index or little fingers,15 tears were on the ulna side of the extensor tendon and 12 tears were on the radial side. A pseudobursa was encountered in 35%, capsular tears in 28% and chondral injury in one patient. Longitudinal curved metacarpophalangeal joint incisions were used, with hood repair performed in flexion using a locked running suture. Mean postoperative metacarpophalangeal joint flexion was 90°. Ninety-eight per cent returned to the same level of boxing at a mean of 8 months (range 1-24) from surgery. One finger was revised for re-rupture 6 months later. A reproducible technique for treating these injuries is described, with patients able to return to boxing with little risk of complications.Level of evidence: IV.

Keywords: Extensor hood injury; elite athlete; outcomes; return to sport; surgical repair.

Figure 1.

Skin incision. A curved longitudinal incision avoids a scar over the striking point of the knuckle.

Figure 2.

Little finger extensor tear. Longitudinal split in the extensors of the little finger between extensor digitorum and extensor digiti minimi tendons.

Figure 3.

Chronic tear. Chronic extensor hood tears, even with rolled up edges, can often be debrided and a primary suture repair achieved.

Figure 4.

Capsule repair. The capsule should only be repaired with the metacarpophalangeal joint in 90° of flexion. If this cannot be achieved, the capsule should be left open to heal by secondary intention.

Figure 5.

Repair of little finger extensor tear. Little finger extensor tear (from Figure 2) repaired with a running locked suture inserted with the metacarpophalangeal joint at 90°.

Figure 6.

Strengthening exercises. After 4 weeks the patient may start isometric contractions of the long flexor tendons and strengthening the intrinsic muscles.