Long-Term Follow-Up of Flexor Digitorum Longus Transfer and Calcaneal Osteotomy for Stage Ii Posterior Tibial Tendon Dysfunction

SLR - June 2015 - Alyssa Roskop

Reference: Chadwick D, Whitehouse SL, Saxby TS. Long-term follow-up of flexor digitorum longus transfer and calcaneal osteotomy for stage II posterior tibial tendon dysfunction. Bone Joint J. 2015 Mar; 97-B(3): 346-52.

Scientific Literature Review

Reviewed By: Alyssa Roskop, DPM
Residency Program: Southern Arizona VA Healthcare System

Podiatric Relevance: Foot and ankle specialists commonly address patients with symptoms related to adult acquired flatfoot deformity due to posterior tibial tendon dysfunction (PTTD). Specifically, in patients with Johnson and Strom Stage II PTTD, after failing conservative treatment, surgical intervention often includes soft tissue and joint preserving osseous procedures. The authors of this article performed both flexor digitorum longus (FDL) transfers and medial displacement calcaneal osteotomies to treat Stage II PTTD patients. They sought to determine if these two procedures performed simultaneously could provide long-term symptom relief in adult acquired flatfoot deformity.

Methods: This retrospective study included patients with symptomatic stage II PTTD who were treated with an FDL transfer and medial displacement calcaneal osteotomy from 1994 to 1996, by the tertiary author in Brisbane, Australia. Patients presented with medial hindfoot pain and swelling, asymmetrical flatfoot deformity with abduction of the forefoot, and a mobile hindfoot, unable to single heel-rise. All patients failed a six-month minimum of conservative treatment including splints, orthotics, activity modification, physiotherapy, and analgesia. A minimum of 11 years follow-up was reviewed. The patients were assessed using the American Orthopedic Foot and Ankle Society (AOFAS) hindfoot/ankle score and a visual analogue score (VAS) for pain. Assessments were performed comparing the operated foot with the asymptomatic foot both preoperatively and at the final follow-up. Short Form (SF)-36 questionnaire was also obtained at the final follow-up to determine patient satisfaction with the operation.

Results: Forty-eight patients met inclusion criteria set forth by the authors. Out of the 48 patients, 15 were lost to follow up, while two patients were deceased unrelated to the surgical procedures performed in this study.  A total of 31 patients were available for review with a mean of 15.2 years post-operatively. Four procedure failures were noted, with failure of the procedure defined as recurrent pain and loss of function, not controlled by simple analgesia or orthotics, requiring further surgery on the hindfoot. All patients achieved a plantigrade foot and all were able to single heel-rise by a mean of five months post-operatively. The mean function component of the AOFAS score improved from 35.8 to 45.6 and the mean total AOFAS score rose from 48.8 to 90.3. The mean VAS score preoperatively was 7.3 but decreased to 1.3 at the time of this study. The SF-36 questionnaire revealed 87 two to four were completely satisfied with the procedure.

Conclusions: There are many different procedures used to surgically treat stage II PTTD. The authors of this study propose the use of FDL transfer with a medial displacement calcaneal osteotomy as a simple, reproducible, and safe procedure. The overall improvement reported, does suggest these two procedures should be considered when performing surgical correction of this patient population.