What is the most common complication after subtalar joint arthroereisis with MBA?

• A. Hardware failure
• B. Sinus tarsalgia
• C. DVT
• D. Superficial infection

Answer: (B)

Placing an MBA device in the subtalar joint aims to limit excessive pronation and realign the hindfoot by occupying the sinus tarsi area. The most common complication is sinus tarsalgia, a painful irritation in the sinus tarsi from the implant’s pressure or impingement on the surrounding soft tissues and bony structures during gait. This irritation tends to occur more frequently than other potential issues in this procedure, such as hardware failure, deep venous thrombosis, or superficial infection, which are less common in the pediatric/ambulation context of subtalar arthroereisis. Mild sinus tarsalgia often improves as healing progresses, while persistent symptoms may be addressed with implant adjustment or removal.