Open Reduction and Primary Subtalar Arthrodesis for Acute Intra-articular Displaced Calcaneal Fractures

SLR - August 2021 - Ryan J. Lerch

Reference: Schipper ON, Cohen BE, Davis WH, Ellington JK, Jones CP. Open Reduction and Primary Subtalar Arthrodesis for Acute Intra-articular Displaced Calcaneal Fractures. Journal of Orthopaedic Trauma. 2021 June 35;6 296-299

Level of Evidence: Therapeutic level IV

Scientific Literature Review

Reviewed By: Ryan J. Lerch, DPM
Residency Program: University of Pittsburgh Medical Center – Pittsburgh, PA

Podiatric Relevance: Calcaneal fractures can be a difficult injury to manage with many different studies looking at nonoperative management versus open reduction and internal fixation through a lateral extensile or sinus tarsi approach. Patients can develop persistent arthritic pain following a calcaneal fracture, especially with increased comminution and disruption of the articular surface. In patients with complex fractures one can certainly argue that primary subtalar arthrodesis will lower the risk of post-operative arthritic complaints and reduce secondary surgeries; further reducing cost and time. This study showed relatively good results with primary fusion of the subtalar joint with displaced intra-articular calcaneal fractures.

Methods: Retrospective chart review of 35 patients, 18 years or older who sustained an acute displaced intra-articular calcaneal fracture who underwent open reduction and primary subtalar arthrodesis from 2006 to 2016. Fractures had to be less than six weeks from injury and displacement greater than 2 millimeters. Exclusion included history of previous calcaneal or talus fracture. Outcome measures included post-operative CT scan to evaluate the posterior facet, Foot and Ankle Ability Measure, Coughlin satisfaction scores and the Veterans RAND Iteam Health Survey. Each fracture was classified based on Sanders I-IV classification. Fusion defined at greater than 25 percent bony bridging across the posterior facet at the widest point. Postoperative radiographs were used to measure lateral talocalcaneal and Bohler's angle.

Results: Average age was 47.8 years with a median follow up on 34.4 months. The Sanders classification included one type II, 14 type III and 20 type IV. The median CT scan follow up was at 6.8 months. Seven patients were workers’ compensation injuries. Extensile lateral approach was used in 31.4 percent and sinus tarsi approach was using in 68.6 percent. Arthrodesis was selected in type II and III fractures if the joint was deemed non-reconstructable. Lateral talocalcaneal angle and Bohler’s angle at final follow up was 28.6 and 26.3 respectively. Primary subtalar union occurred in 94.3 percent of patients (33/35). Two of the 35 patients had a nonunion, and one underwent revisional arthrodesis. Coughlin satisfaction scores were good to excellent in 71.4 percent of patients. There was no difference in post-operative satisfaction and FAAM scores between workers’ compensation patients and those without workers’ compensation. 

Conclusions: This is the first study to look at fusion rates based on CT scans following open reduction and primary subtalar arthrodesis of DIACF. This study is similar to previously reported union rates but those were based on radiographs. Complications in this study were similar to previous reports including one deep infection, two hardware irritations, one sural neuritis and one malunion requiring revision. Post-operative satisfaction and function scores in this study demonstrated good to excellent results comparable to current literature. Limitations included small sample size, selection bias and no preoperative scores. Open reduction and primary fusion of the subtalar joint yielded high union rates and should be considered as a primary treatment for patients with significant cartilage injury and comminution of the posterior facet.