[Clinical observation of sinus tarsi syndrome after lateral ankle sprain]

To study the incidence rate of sinus tarsi syndrome after lateral ankle sprain and observe the clinical efficacy of sinus tarsal corticosteroid injections.

From January 2021 to Janury 2022, 391 patients with lateral ankle sprain and 88 patients with sinus tarsi syndrome using corticosteroid injections (compound betamethasone 1 ml+ lidocaine hydrochloride 4 ml) were retrospectively analyzed. There were 22 males and 66 females, aged from 29 to 60 years old with an average of (41.00±7.52) years old, duration of the disease from 1 to 12 months with an average of (5.6±4.2) months. The visual analogue scale(VAS) and American Orthopedic Foot and Ankle Society(AOFAS) scores were collected before, 1 month, 3 months, 6 months, and 12 months after treatment.

All 88 patients completed a 12-month follow-up. The incidence rate of sinus tarsi syndrome after lateral ankle sprain was 22.5%. One month after treatment, VAS was 1.20±0.89, AOFAS score was 88.70±7.04. Three months after treatment, VAS was 1.60±1.35, AOFAS score was 85.20±10.95. Six months after treatment, VAS 2.35±1.39, AOFAS 80.30±9.75. Twelve months after treatment, VAS was 2.80±1.51, AOFAS score was 79.1±9.94. Significant differences were found before and after treatment at all four time points of follow-up(P<0.05).

The results of this study showed that the incidence rate of sinus tarsi syndrome after lateral ankle sprain was 22.5%. Corticosteroid injections were effective in the short term with a 65% recurrence rate of symptoms within 1 year. For patients with no significant long-term effect of conservative treatment, clinicians may explore alternative approaches, including options like ankle arthroscopy.