Traditional open approaches for subtalar arthrodesis have reported nonunion rates of 5–16% and significant incidence of infection and nerve injury. The rationale for arthroscopic arthrodesis is to limit dissection of the soft tissues in order to preserve blood supply for successful fusion, whilst minimising the risk of soft tissue complications. The aim of this study was to determine the outcomes of sinus tarsi portal subtalar arthrodesis.

Case records of all patients undergoing isolated arthroscopic subtalar arthrodesis by two senior surgeons between 2004 and 2014 were examined. All patients were followed up until successful union or revision surgery. The primary outcome measure was successful clinical and radiographic union. Secondary outcome measures included occurrence of infection and nerve injury.

Seventy-seven procedures were performed in 74 patients, with successful fusion in 75 (97.4%). One (1.3%) superficial wound infection and one (1.3%) transient sural nerve paraesthesia occurred. Fixation with a single screw provided sufficient stability for successful arthrodesis.

To our knowledge this is the largest reported series of isolated arthroscopic subtalar arthrodeses to date, and the first series reporting results of the two portal sinus tarsi approach. This approach allows access for decortication of all three articular facets, and obviates the need for a posterolateral portal, features which may explain the high union rate and low incidence of sural nerve injury in our series.

Introduction:

Symptomatic tarsal coalitions failing conservative treatment are traditionally managed by open resection. Arthroscopic excision of calcaneonavicular bars have previously been described as has a technique for excising talocalcaneal bars using an arthroscope to guide an open resection. We describe a purely arthroscopic technique for excising talocalcaneal coalitions. We present a retrospective two-surgeon case series of the first eight patients (nine feet).

We report a single surgeon series of 33 arthroscopic subtalar fusions performed through a 2-portal sinus tarsi approach on 32 patients between March 2004 and February 2009. Background pathologies included primary arthrosis, post-traumatic arthritis, planovalgus foot, rheumatoid disease, sinus tarsi syndrome and CTEV.

97% [32/33] of fusions as assessed by both clinical and radiological means were achieved within 16 weeks [76% [25/33] within 12 weeks] with only a single outlier which had fused by 22 weeks. There were no deep infections, thrombotic events or neuromas. Five patients suffered complications of which four were successfully treated with a satisfactory outcome. One patient developed persistent pain and was eventually referred to another centre for further management.

In our experience arthroscopic subtalar fusion surgery has been demonstrated to give excellent outcomes with minimal complications. Furthermore, it is a technique allowing surgery even in patients with significant hindfoot deformity. It is a suitable operation even for patients with a compromised soft tissue envelope which would normally preclude an open procedure.