Is Peroneal Spastic Flatfoot Causing Chronic Ankle Pain?
A 14-year-old male athlete comes into your office with a chief complaint of ankle pain. He says he had the pain right after a soccer match. His parents and coach concluded that he had sprained his ankle. However, despite treatment, which consisted of rest, ice and the use of an Ace wrap, the patient’s pain continued for two months. He has pain in his ankle when standing and walking, and is not able to run or return to play.
Upon further questioning, you find out that neither his foot nor his ankle were ever swollen or ecchymotic, and he cannot recall an exact instance of twisting his ankle.
This is the most common presenting scenario of a patient with a peroneal spastic flatfoot and until this condition is considered as a potential diagnosis, this young athlete will find himself going from doctor to doctor continually being treated for an ankle sprain.
The patient with peroneal spastic flatfoot complains of pain, chronic ankle sprains and flatfoot. Pain occurs in the subtalar or midtarsal area of the involved foot. It usually occurs after some unusual activity or minor trauma and is aggravated by walking, prolonged standing, jumping or participating in athletics. Rest relieves the pain. In severe cases, you may see an antalgic gait and the patient may have a significant limp.
Upon examining those who have peroneal spastic flatfoot, you’ll usually find a stiff foot and often there will be decreased motion of the subtalar joint. Clinically, you may notice a loss of the longitudinal arch, limited subtalar motion, hindfoot valgus and forefoot abduction. Forced inversion of the foot will exacerbate the symptoms.
Is A Tarsal Coalition The Culprit?
Tarsal coalitions are the most common cause of peroneal spastic flatfoot. These coalitions may be either congenital or acquired and may have a genetic predisposition. Trauma, infection, arthritis and neoplasms can cause acquired coalitions, which are less common in pediatric patients than adults. The true incidence of tarsal coalition is unknown. Current reports consider it to be less than 1 percent.
The most prevalent coalitions are calcaneonavicular, talonavicular and talocalcaneal. Among these, calcaneonavicular coalitions appear to predominate. The coalition may be completely osseous (i.e., synostosis) or the bones may be divided by a fissure of varying depth, consisting of cartilage (i.e., synchondrosis) or fibrous tissue (i.e., syndesmosis).
Tarsal coalitions may occur bilaterally or unilaterally. Talonavicular fusions are usually present in both feet. Calcaneonavicular coalitions are bilateral in 60 percent of patients and talocalcaneal coalitions are bilateral in 50 percent. In infancy and early childhood, the condition is usually asymptomatic and is seldom recognized. Symptoms of the calcaneonavicular coalition usually appear between 8 and 12 years of age and those of the talocalcaneal coalition occur during adolescence. The talonavicular coalitions often remain asymptomatic.
Even though coalitions are the most likely cause of peroneal spastic flatfoot, they are not the only causative factor. It is recognized that any inflammatory pain surrounding the ankle or subtalar joint can result in this condition. Other etiologies of peroneal spastic flatfoot may include tuberculosis, osteomyelitis, trauma, osteoarthritis, rheumatoid arthritis, Sudeck’s atrophy (reflex sympathetic dystrophy), nonspecific tarsal synovitis, osteochondral fractures, osteoid osteoma, postoperative subtalar arthrodesis and synovial irritation created by altered biomechanics of the foot.