yoga book / pathology / calcaneofibular impingement

Definition

Calcaneofibular impingement is a painful impingement between the lateral calcaneus and the lateral malleolus of the fibula. As such, it is classified as external impingement. This condition almost always occurs secondarily following trauma, surgery or in the context of pronounced valgus deformity of the calcaneus in the context of a pronounced flat foot, usually against a background of PTTD with a tendency towards subtalar subluxation. This aetiopathology is likely to be the most common. Symptomatically, the predominant feature is pain on weight-bearing in the lateral hindfoot, beneath and slightly in front of the lateral malleolus. This may be accompanied by swelling or a grinding/cracking sensation. X-rays may reveal bony changes, such as deformities or fractures, as well as bone marrow oedema syndrome, which is even more clearly visible on MRI. Calcaneofibular impingement must not be confused with the anterolateral form of ankle impingement. It is most commonly seen in middle-aged or older people with a long-standing flat foot. Occasionally, there is an accompanying subluxation of the fibularis longus with a corresponding snapping sensation. In various sources, this condition is also referred to as subtalar impingement or sinus tarsi impingement.

Cause

1. subtalar subluxation
2. trauma
3. post-operative
4. pronounced clubfoot/flat foot
5. calcaneal fractures with inadequate blood supply
6. chronic synovitis
7. hypertrophic soft-tissue structures

Predisposing

1. talipes valgus/flat feet
2. Posterior Tibial Tendon Dysfunction (PTTD)
3. subtalar osteoarthritis with osteophyte formation
4. rheumatic diseases

Diagnosis

1. Inspection: talipes valgus
2. palpation: tenderness
3. eversion pain provocation test
4. tests and signs: anterior drawer tests, talar tilt test 1, talar tilt test 2

Symptoms

1. pain on exertion with a stabbing sensation, worsening when walking on uneven ground or climbing stairs
2. where applicable, resting pain
3. pain or increased pain during pronation
4. possibly accompanied by fibular subluxation
5. tenderness below the medial malleolus

Therapy

1. surgical: removal of adjacent bone or soft tissue
2. calcaneal repositioning osteotomy
3. subtalar arthrodesis (resection of the superolateral calcaneus process or medialising calcaneal osteotomy)
4. insole with rearfoot supination wedge
5. infiltration therapy
6. strength training, particularly for the tibialis posterior
7. assessment and optimisation of the muscles involved in movements of the talocrural joint and subtalar joint

Complications

1. chronicity
2. rupture of the peroneal tendons
3. lesions of the sural nerve
4. early-onset secondary osteoarthritis of the subtalar joint
5. arthrofibrosis / recurrent tissue proliferation following incomplete debridement or post-operative malunion

DD

1. subtalar arthritis or osteoarthritis
2. sinus tarsi syndrome