Single longitudinal dorsal incision approach to transfer the flexor digitorum longus tendon between the flexor digitorum brevis hemitendons: a cadaveric study.

Transposition of the flexor digitorum longus tendon has been widely reported for the correction of flexible claw and hammertoe deformities. The most common technique uses two cutaneous incisions, one plantar and another dorsal. We performed a cadaveric study to determine whether the flexor digitorum longus tendon could be transferred to the dorsum of the proximal phalanx of the toe from its lateral or medial aspect through a unique single longitudinal central dorsal incision. The rationale for this novel approach was to minimize the risk of vascular compromise to the digit associated with the two-incision approach. Transposition of the flexor digitorum longus tendon was attempted in 120 toes of cadaveric feet (60 each second and third digits) through a central longitudinal dorsal incision. The flexor digitorum longus tendon segment was long enough to be successfully transposed between the flexor digitorum brevis hemitendons of the second and third toes in 100% of the cases using the central longitudinal dorsal incision approach, with a resection arthroplasty at the proximal interphalangeal joint. Transfer of the flexor digitorum longus tendon to the dorsum of the proximal phalanx can be performed for the correction of claw and hammertoe deformities in the second and third digits. The meticulous longitudinal incision of the flexor tendon sheath to expose the flexor digitorum brevis tendon and its longitudinal incision are essential to the successful transfer of the flexor digitorum longus tendon between the flexor digitorum brevis hemitendons.