Flexor hallucis longus transfer corrected clawed hallux

This technique was an effective surgical alternative to modified Jones procedure.

Issue: November 2004

AOFAS Seattle [icon] Flexor hallucis longus transfer is an effective surgical alternative to the modified Jones procedure for correcting clawed hallux, according to a study presented at the American Orthopaedic Foot and Ankle Society 20th Annual Summer Meeting.

“All subjects were satisfied or somewhat satisfied with the flexor hallucis longus (FHL) transfer,” reported Emily Donaldson-Fletcher, investigator for the study that assessed the radiological and functional outcomes of FHL transfer for correction of clawed hallux associated with cavus foot deformity. “In contrast, studies of the modified Jones procedure have reported a dissatisfaction rate of 9% to 21%.”

Donaldson-Fletcher described the FHL transfer, an alternative procedure for correction of clawed hallux: “After the medial incision the FHL tendon is isolated, cut distally, threaded through a drill hole in the proximal phalanx from plantar to dorsal and sutured to itself.”

The modified Jones procedure is traditionally used for correction of clawed hallux. Clawed hallux deformity is generally attributed to a muscular imbalance that may be caused by over-pull of one of three different muscles.

As an alternative to the modified Jones procedure, the FHL transfer does not remove the extensor hallucis longus (EHL) function and does not require fusion of the interphalangeal (IP) joint.

Donaldson-Fletcher and colleagues retrospectively assessed the outcomes of the FHL transfer procedure for correction of clawed hallux associated with cavus foot deformity. Two surgeons treated 19 patients; 22 FHL transfers were performed. Average patient age at operation was 46.9 years. Follow-up occurred an average of 50.1 months after the procedure. Patients had an average of 4.7 concomitant procedures with a range from five to 11 procedures in addition to FHL transfer.

The investigators measured outcome and patient satisfaction using the long-form Musculoskeletal Function Assessment (MFA) score. Additionally, patients were contacted by telephone and asked whether they were satisfied, somewhat satisfied or dissatisfied with the overall result.

Pre- and postoperative weight-bearing radiographs were used to measure hallux valgus and IP angle on anteroposterior radiographs; the angle of the IP joint and the metatarsophalangeal (MP) joint was measured on the lateral view.

Joint angle reductions

The IP joint angle was significantly reduced postoperatively (P<.0005) with an average reduction of 21.3º (±4.7 SE), changing from a mean of 28.1º preop to 6.8º postop. The average reduction of the MP angle was 13.4º (±4.5 SE), changing from a mean of 36.5º preop to 23.1º postop (P<.008).

Sixty-eight percent of patients undergoing FHL transfer said they were satisfied with their outcome, Donaldson-Fletcher said, and 32% of patients undergoing the procedure said they were somewhat satisfied. No patients were unsatisfied.

For more information:

Kadel NJ, Donaldson-Fletcher E, Sangeorzan BJ, Hansen ST. Alternative to the modified Jones procedure: Outcomes of the flexor hallucis longus (FHL) transfer procedure for correction of clawed hallux. Presented at the American Orthopaedic Foot and Ankle Society 20th Annual Summer Meeting. July 29-31, 2004. Seattle.