Risks Associated With Posterior Ankle Hindfoot Arthroscopy Complications.

BACKGROUND: The use of posterior ankle and hindfoot arthroscopy (PAHA) has been expanding over time. Many new indications have been reported in the literature. The primary objective of this study was to report the rate of PAHA complication in a large cohort of patients and describe their potential associations with demographical and surgical variables.

METHODS: In this IRB-approved retrospective comparative study, patients who underwent posterior ankle and/or hindfoot arthroscopy in a single institution from December 2009 to July 2016 were studied. Three fellowship-trained orthopaedic foot and ankle surgeon performed all surgeries. Demographic data, diagnosis, tourniquet use, associated procedures, and complications were recorded. To investigate a priori factors predictive of neurologic complication after PAHA, univariate and multivariable logistic regression was utilized. Where appropriate, sparse events sensitivity analysis was tested by fitting models with Firth log-likelihood approach.

RESULTS: A total of 232 subjects with 251 surgeries were selected. Indications were posterior ankle impingement (37%), flexor hallux longus disorders (14%), subtalar arthritis (8%), and osteochondral lesions (6%). Complications were observed in 6.8% (17/251) of procedures. Neural sensory lesions were noted in 10 patients (3.98%), and wound complications in 4 ankles (1.59%). Seven neurologic lesions resolved spontaneously and 3 required further intervention. In a multivariable regression model controlled for confounders, the use of accessory posterolateral portal was the significant driver for neurologic complications (odds ratio [OR] 32.19, 95% CI 3.53-293.50).

CONCLUSION: The complication rate in this cohort that was treated with posterior ankle and/or hindfoot arthroscopy was 6.8%. Most complications were due to neural sensorial injuries (sural 5, medial plantar nerve 4, medial calcaneal nerve 1 ) and 3 required additional operative treatment. The use of an accessory posterolateral portal was significantly associated with neurologic complications. The provided information may assist surgeons in establishing diagnoses, making therapeutic decisions, and instituting surgical strategies for patients that might benefit from a posterior arthroscopic approach.

LEVEL OF EVIDENCE: Level III, retrospective comparative study.