Subtalar Distraction Arthrodesis Using Fresh-Frozen Allogeneic Femoral Head Augmented With Local Autograft

SLR- January 2014- Nicole Brouyette

References: Chiang CC,Tzeng YH, Lin CF, Huang CK, Chen WM, Liu CL, Chen TH. Subtalar Distraction Arthrodesis Using Fresh-Frozen Allogeneic Femoral Head Augmented With Local Autograft. Foot & Ankle International. 2013. 34(4) 550-556.

Scientific Literature Review

Reviewed By: Nicole Brouyette, DPM
Residency Program: St. John’s Hospital and Medical Center

Podiatric Relevance: Mobility can be a limiting functional agent in the presence of decreased calcaneal body height, impingement of the talar neck and loss of ankle dorsiflexion. These symptoms can arise as a late complication of a malunion in calcaneal fractures. Patients with chronic pain and permanent functional incapacity due to subsequent post-traumatic subtalar osteoarthritis may need future surgical intervention.

Methods: A retrospective study was performed between March 2007 and March 2009 on 13 consecutive patients with 15 calcaneal malunions. Five patients were male and eight were female. During this time all subtalar joint distraction arthrodesis (SDA) reconstructions were performed for calcaneal malunion with the use of fresh frozen allogeneic femoral head. Indications for the procedure included symptomatic subtalar arthritis, loss of heel height, dorsiflexion of the talus with anterior impingement, and failed non-operative treatment. Of the 15 feet used in the study, the initial injury was treated as follows: two patients open reduction and internal fixation, five patients with closed reduction and pinning, five patients were casted and three patients received no treatment. The median time betweeninjury and SDA was 18 months and the median follow up time postoperatively was 36 months. The AOFAS and VAS were assessed preoperatively and at the last follow-up. All patients were examined by the primary author with biomechanical exams. Radiographic assessment included weight bearing lateral views assessing the talar declination angle, calcaneal inclination angle and lateral talocalcaneal angle, heel height and calcaneal length. Radiographic union was determined by the bridging trabeculation across the recipient-graft-recipient junction on thelateral projection. Patients were followed up weekly during the first month, and monthly to the six months point, and every six months until the last follow-up visit. Patients were placed in short leg splints or casted for three months without weight bearing for the first 10 weeks and partial weight bearing beginning after 10 weeks.

Results: The preoperative AOFAS ankle-hindfoot scorewas 50.0 and the VAS pain score was 72.0 and at the latest follow up visit themedian AOFAS score was 76.0 and VAS pain score was 22.5, SF-12 physical health summary was 47.0 and SF-12 mental heath summary was 52. The differences preoperatively verses postoperatively were statistically significant when comparing the AOFAS and VAS pain scores. However, there was nosignificant change in dorsiflexion, plantar flexion or total range of motion ofthe ankle after surgery. The satisfaction rate was 93.3 percent. Radiographic results showed improved significant differences. The median increased in heel height was 8.6mm. The median decrease in heel height from three months after surgery to the last follow-up visit was 0.6mm. Union was achieved in all cases at a medianof 13.0 weeks.

Conclusion: Using fresh-frozen allogeneic femoral headaugmented with local autograft for treatment of calcaneal malunions, this study demonstrated good surgical outcomes with subtalar distraction arthrodesis. Postoperatively the AOFAS, VAS, TDA,CIA, LTCA and heel height significantly improved. Union was achieved within 13 weeks and collapse of the femoral head was minimal after three months. Mobility of the ankle joint and calcaneal length did not improve after subtalar distraction arthrodesis. In conclusion, treatment of complex calcaneal malunion with SDA and interposition of fresh-frozen allogeneic femoral head augment with local autograft was a reliable and reproducible option with the benefits including; no donor site morbidity, availability without limitation of size and no extra cost of other orthobiological agents.