Degenerative osteoarthritis of the second metatarsophalangeal joint: second toe rigidus.

PURPOSE: The purpose of this study was to evaluate the radiographic characteristics and structural configurations of a series of patients with a primary degenerative arthritis of the second metatarsophalangeal joint.

METHODS

We studied 37 feet that had undergone surgical treatment for primary degenerative arthritis of the second metatarsophalangeal joint. The patients were compared with a randomly selected control group, without arthritis of the second metatarsophalangeal joint. The first, second, and fourth metatarsal lengths, and the size of the second metatarsal head were measured on weight-bearing anteroposterior radiographs. The patients were classified on the basis of joint-space narrowing, subchondral sclerosis, osteophyte formation, and subchondral cystic change.

RESULTS

The average second metatarsal length was significantly longer in the study group (P = 0.01). The average length of the first metatarsal relative to the fourth metatarsal was significantly shorter (P = 0.02) in the study group, while the average length of the second metatarsal relative to the fourth metatarsal was significantly longer (P = 0.01) in the study group. The average diameter of the second metatarsal head was significantly larger in the study group (P = 0.00), and the average ratio of this diameter relative to the length of the fourth metatarsal was significantly higher in the study group (P = 0.00). A total of four feet were classified as grade 0, nine as grade 1, 17 as grade 2, and seven as grade 3.

CONCLUSIONS

Second toe rigidus should be considered as a diagnosis in patients with painful limited dorsiflexion of the second metatarsophalangeal joint without evidence of Freiberg's infraction or trauma.