Fibular Tip Periostitis: New Radiographic Sign Predictive of Chronic Peroneal Tendon Subluxation-Dislocation in Pes...

Area of Science:

• Orthopedic imaging
• Radiology
• Sports medicine

Background:

• Superior peroneal retinaculum tears cause peroneal tendon subluxation-dislocation.
• These injuries are often radiographically occult, except for fibular avulsions.

Purpose of the Study:

• To investigate the association between fibular tip periostitis and peroneal tendon subluxation-dislocation in hindfoot valgus patients.
• To determine if fibular periostitis predicts peroneal tendon subluxation-dislocation on MRI.

Main Methods:

• Retrospective analysis of 35 patients with fibular tip periostitis and 35 controls with hindfoot valgus.
• Both ankle radiography and MRI were reviewed by musculoskeletal radiologists.
• Evaluated for peroneal tendon subluxation-dislocation, subfibular impingement, and hindfoot valgus angle.

Main Results:

• Peroneal tendon subluxation-dislocation was significantly more frequent in patients with fibular periostitis (62.9%-85.7%) versus controls (5.7%-14.3%).
• Fibular periostitis showed high sensitivity and specificity for predicting peroneal tendon subluxation-dislocation.
• Subfibular impingement and larger hindfoot valgus angles were also associated with fibular periostitis.

Conclusions:

• Radiographic fibular tip periostitis is a predictor of peroneal tendon subluxation-dislocation in hindfoot valgus.
• This finding may indicate advanced hindfoot valgus and subfibular impingement.
• Radiologists should recognize this association and consider MRI when indicated.