[Involvement of the foot in reactive arthritis. A retrospective study of 105 cases]

The foot is among the sites most often affected in spondyloarthropathies, whose diagnostic criteria include heel pain and sausage-like swelling of the toes. Few studies have systematically analyzed foot manifestations in reactive arthritides. We retrospectively reviewed 143 patients fulfilling Amor's criteria. One hundred five patients (73%) exhibited inflammatory involvement of one (n = 47) or both feet. In 8 cases no other articular sites were affected. Heel pain was reported by 36% of patients (52/143), within the first six months in half the cases. Both heels were painful in 26 patients. Heel pain was plantar in 36 cases, posterior in 7 cases, and bipolar in 4 cases. Roentgenographic calcaneal changes were found in 54 cases overall but in only 31 of the patients with heel pain. Sixteen patients had asymptomatic calcaneitis. Seventeen patients had involvement of the transverse tarsal joint, usually with no other affected joints. Involvement of the subtalar joint was rare (6 cases). Metatarsophalangeal manifestations were found in 44% of patients (64/143) and were symmetrical in 17 cases; 17 patients had changes of the great toe suggestive of gout. Interphalangeal arthritis was seen in 22% (32/143) of cases; in half these cases the first two rays were affected and sausage-like digital swelling was seen in 28 patients (20%). Permanent roentgenological damage was uncommon.