II. Epidemiology
- Most common in children and teens
III. Pathophysiology
- Anatomy of variably present accessory bones (result from incomplete fusion of the talus)
- Os Trigonum (Variant present in 14-25%)
- Adjacent to the Talus posterior margin
- Accessory Tarsal Navicular (Variant present in 4-14%)
- Adjacent to medial and posterior Tarsal Navicular margin
- Os Trigonum (Variant present in 14-25%)
- Os Trigonum Syndrome
- Pain at the Os Trigonum provoked by high impact sports
IV. Mechanism
- Jumping activities
- Specific associated sports
- Ballet
- Dance
- Gymnastics
- Soccer
V. Symptoms
- Posterior ankle pain
- Antalgic Gait
VI. Signs
- Stieda's process
- Pain on extreme plantar flexion
- Heel thrust maneuver
- Patient lies prone with foot in dorsiflexion
- Examiner
- Palm of one hand on the patient's heel
- Holds the patient's posterior distal calf with the other hand
- Maneuver
- Patient's heel is pushed toward the head (cranially)
- Posterior ankle pain is a positive test
- Passive plantar hyperflexion
- Patient lies prone
- Examiner passively plantar flexes the ankle to >50 degrees
- Posterior ankle pain with passive plantar flexion is positive test for posterior ankle impingement
VII. Imaging
-
Ankle XRay
- Lateral Ankle XRay with with a well-corticated ossicle posterior to the talus
- Compare with XRay of opposite foot
VIII. Management
- Conservative measures to reduce pain on plantar flexion
- Modify activity to reduce provocative measures
- NSAIDs
- Consider taping and bracing
-
Ultrasound guided Corticosteroid Injection
- May allow for earlier return to sport (within 3-4 weeks)
- Surgery may be considered in refractory course
- May be needed in up to 15% of patients
- Expect return to full activity in 70-80% of patients at 13-18 weeks