Arthroscopic Subtalar Joint Arthrodesis: Topical Review

Abstract

Background: Advances in foot and ankle arthroscopy over the last 2 decades have allowed for subtalar joint arthrodesis to be performed arthroscopically. The potential advantages of the arthroscopic technique include higher fusion rates, lower complications, reduced perioperative morbidity, and accelerated rehabilitation. Arthroscopic arthrodesis may, however, not be appropriate in the setting of complex deformity correction or the need for other open procedures. Methods: Surgical techniques of arthroscopic subtalar joint arthrodesis are described. Outcomes and complications associated with these procedures are presented, based on a comprehensive literature review. Thirteen Level IV studies of moderate quality were included. Results and Conclusion: Excellent arthrodesis union rates were achieved (average 96%, range 86%-100%), at a weighted average union time of 8.8 weeks (95% confidence interval 7.9-9.7). The overall complication rate was 21% (87/415 feet; range 10%-36.4%). Metal irritation was the most common complication (11.2%), followed by nerve injury (4.2%) and infection (0.9%). Similar fusion rates have been reported when comparing arthroscopic and open arthrodesis. Complication rates are also similar, excerpt for infection, which may be lower with arthroscopy. Three different approaches were used to access the subtalar joint with similar union and complication rates. There was no evidence that the use of bone graft or more than 1 screw improved outcomes. The superiority of arthroscopic subtalar fusion over open techniques cannot be demonstrated by the available studies. Level of Evidence: Level IV, case series.

Subtalar Arthrodesis Union Rates With and Without Adjacent Ankle Arthrodesis

“…Previous studies have demonstrated risk factors for subtalar nonunion to include a prior ankle arthrodesis, as well as an increased body mass index, diabetes mellitus, and neuropathy. 10,18 There has been limited published data on the union rates of a subtalar arthrodesis below an ankle. Zanolli et al 19 undertook 151 subtalar arthrodeses, of which only 13 were below an ankle.…”

“…Previous studies have demonstrated risk factors for subtalar nonunion to include a prior ankle arthrodesis, as well as an increased body mass index, diabetes mellitus, and neuropathy. 10,18…”

Posterior Ankle and Hindfoot Arthroscopy: A Contemporary Review

“…Other authors have reported similar nerve injury rates of 4.2%. 51 Although these numbers are not insignificant, other authors have reported higher rates of sural nerve injury with open subtalar arthrodesis when compared to arthroscopic. 59 Although many authors have raised concerns regarding the proximity of the posteromedial portal to the vascular structures in cadaveric studies, 20,76 the large number of reports demonstrating safety with regard to injury to the tibial neurovascular bundle have questioned this line of thinking.…”

“…Other authors have reported similar nerve injury rates of 4.2%. 51 Although these numbers are not insignificant, other authors have reported higher rates of sural nerve injury with open subtalar arthrodesis when compared to arthroscopic. 59…”

“…Grouped broadly, indications for prone posterior ankle arthroscopy can be divided into those involving bone, cartilage, or soft tissue pathologies. Commonly addressed bone pathologies include fractures of the posterior hindfoot, 8,9,11 hypertrophic posterior talar process, 66 removal of loose bodies, 52 avulsion fractures, 22 posterior facet talocalcaneal coalition, 7,10,51,59,69 Haglund deformity, 79 intraosseous cystic lesions, 60 and posterior impingement, which comprises os trigonum syndrome and a prominent trigonal process. 57,78 Cartilage pathologies that are addressed with arthroscopy include posterior talar, tibial, or calcaneal osteochondral defects, 35 subtalar arthritis, 4 and synovial chondromatosis.…”