踝关节外侧疼痛---踝关节外撞击综合征

Pathophysiology and Clinical Features

Severe flatfoot and hindfoot valgus deformity may present with lateral ankle pain in the region bounded by the anterior fibula and the sinus tarsi . This lateral ankle pain has been attributed to extraarticular lateral hindfoot impingement including talocalcaneal impingement (between the lateral talus and calcaneus) and subfibular impingement (between the calcaneus and fibula) fig.12A,12B,12C). Lateral hindfoot impingement is believed to be secondary to a lateral shift of weight-bearing forces from the talar dome to the lateral talus and fibula and to talocalcaneal joint subluxation . Talocalcaneal impingement typically occurs before subfibular or combined talocalcaneal–subfibular impingements .

There are several causes of lateral hindfoot impingement including PTT dysfunction , healed intraarticular calcaneal fractures , neuropathic arthropathy, and inflammatory arthritides . Clinical presentation varies on the basis of the cause of flatfoot and hindfoot valgus. In patients with PTT dysfunction, medial ankle pain is the presenting symptom during the early stages of PTT dysfunction, whereas lateral ankle pain related to hindfoot valgus and lateral impingement predominates in long-standing PTT dysfunction . Regardless of the initial cause of flatfoot, patients with rigid flatfoot deformity experience decreased range of motion at the midfoot and hindfoot and decreased ankle dorsiflexion . Lateral ankle pain may develop because of lateral hindfoot impingement. With progressive deformity, secondary osteoarthrosis of the subtalar, talonavicular, and calcaneocuboid articulations contribute to pain symptoms . On physical examination, flatfoot and hindfoot valgus deformity are evaluated with the patient sitting and standing. There may be decreased range of motion of the ankle, hindfoot, midfoot, and forefoot and lateral ankle pain on palpation. The Achilles tendon may show contracture and tightness .

The goal of conservative treatment early in the course of the disease is to prevent further disability and progressive deformity. Acute synovitis is treated with rest and NSAIDS to reduce inflammation. Physical therapy and orthotics relieve stress and pain in the ankle. In patients with advanced PTT dysfunction, soft-tissue balancing procedures alone are inadequate for restoring the longitudinal arch . Osseous correction of hindfoot deformity is required and consists of calcaneal osteotomy, either at the body (medial calcaneal displacement osteotomy) or at the anterior calcaneus (lateral column lengthening). Finally, marked deformity associated with arthritis and fixed osseous deformity are best managed with arthrodesis. These include talonavicular arthrodesis, double arthrodesis at Chopart joints, a subtalar arthrodesis, and a triple arthrodesis. The extent of arthro desis should be limited to minimize the stress transfer to proximal and distal joints .

Fig. 12A—Schematic drawings show lateral extraarticular talocalcaneal and subfibular hindfoot impingements. (Reprinted from [10]) Normal hindfoot valgus (< 6°) and no lateral impingement. Hindfoot valgus angle is measured at intersection of line along medial calcaneal wall and line parallel to longitudinal axis of tibia.

Fig. 12B—Schematic drawings show lateral extraarticular talocalcaneal and subfibular hindfoot impingements. (Reprinted from [10]) With progressive hindfoot valgus, abnormal contact between lateral talus and calcaneus (red) occurs first and results in talocalcaneal impingement.

Fig. 12C—Schematic drawings show lateral extraarticular talocalcaneal and subfibular hindfoot impingements. (Reprinted from [10]) Subsequent abnormal contact between both lateral talus and calcaneus (red) and abnormal contact between calcaneus and fibula (orange) subsequently develop and produce combined talocalcaneal and subfibular impingement.
Fig. 13A—66-year-old woman with talocalcaneal and calcaneofibular impingement due to pes planus and hindfoot valgus. Sagittal inversion-recovery image shows marrow edema of opposing lateral talar process (solid arrow) and calcaneus (open arrow)

Fig. 13B—66-year-old woman with talocalcaneal and calcaneofibular impingement due to pes planus and hindfoot valgus. Sagittal T1-weighted (B) and coronal fat-suppressed proton density–weighted (C) images depict edema and scarring (arrowheads,B) surrounding thickened, entrapped calcaneofibular ligament (arrow). Hindfoot valgus angle, formed by intersection of line along medial calcaneal wall and line parallel to long axis of tibia, is increased (30°).

Fig. 13C—66-year-old woman with talocalcaneal and calcaneofibular impingement due to pes planus and hindfoot valgus. Sagittal T1-weighted (B) and coronal fat-suppressed proton density–weighted (C) images depict edema and scarring (arrowheads,B) surrounding thickened, entrapped calcaneofibular ligament (arrow). Hindfoot valgus angle, formed by intersection of line along medial calcaneal wall and line parallel to long axis of tibia, is increased (30°).
Fig. 14A—61-year-old woman with talocalcaneal and calcaneofibular impingements related to severe hindfoot valgus. Sagittal inversion-recovery image depicts contact between calcaneus and fibula with opposing marrow edema and subchondral cysts (arrows).
Fig. 14B—61-year-old woman with talocalcaneal and calcaneofibular impingements related to severe hindfoot valgus. Coronal proton density–weighted image depicts neocalcaneal facet (solid arrow) articulating with distal fibula. Lateral subluxation of calcaneus and subchondral changes in posterior subtalar facet (arrowheads) are compatible with talocalcaneal impingement. Peroneal tendons (open arrow) are minimally laterally subluxed