Flexor Tendon Laceration Due to Carpal Tunnel Release Surgery: An Impossible Complication

A 55-year-old woman presented with active flexion loss in distal interphalangeal joint of the left little finger following an open carpal tunnel release surgery done 6 months back ([Fig. 1], [Video 1] [available in the online version of this article]). Clinical examination showed no sensory and motor loss in the median and ulnar nerve distribution in the hand. The previous surgical scar in the palm was opened under axillary block with zig zag extensions. The flexor digitorum profundus of the little finger was found cut and separated ([Fig. 2]). The primary repair in this situation was found to be very remote. Hence, the tendon ends were refreshed, bridged with palmaris longus tendon graft harvested from the same side, and sutured by Pulvertaft method. The postoperative was uneventful with no complications. The little finger physiotherapy was started and gradually she had returned back to her normal life with good functional outcome.

Fig. 1 Preoperative view of the hand. There is no active flexion in distal interphalangeal joint.

Fig. 2 Total laceration of flexor digitorum profundus tendon.

Video 1

Loss of flexion in the distal interphalangeal joint during active movements. Online content including video sequences viewable at: https://www.thieme-connect.com/products/ejournals/html/10.1055/s-0036-1581097.

Carpal tunnel syndrome is the most common nerve entrapment of the upper extremity.[1] [2] Surgical release of the transverse carpal ligament is the treatment of choice for patients with severe symptoms and who do not benefit from conservative treatment. Meticulous surgical release provides high success rates.[1] [2] [3] However, various complications can be seen postcarpal tunnel release, which are divided into early and late-term presentations. Incomplete release, painful scar, ulnar and median nerve branches damage (most commonly the palmar cutaneous branch of median nerve), painful neuroma, and superficial palmar arch or ulnar artery injuries are early complications. Scar tenderness, pillar pain, grabbing function limitations, reflex sympathetic dystrophy, and bow stringing in the flexor tendons are late-term complications.[1] [2] [3] [4] [5]

Flexor tendon injury of little finger, following carpal tunnel release surgery is a rare complication. Attention to the carpal tunnel anatomy, meticulous surgical techniques, and safe surgical skills will certainly prevent these complications. In such cases of iatrogenic flexor tendon injury, primary repair or flexor tendon reconstruction with tendon graft remains the mainstay of treatment.

• References

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• 5 Terrono AL, Belsky MR, Feldon PG, Nalebuff EA. Injury to the deep motor branch of the ulnar nerve during carpal tunnel release. J Hand Surg Am 1993; 18 (6) 1038-1040