Higher association of articular surface destruction with rheumatoid forefoot deformity arising from dislocation of the metatarsophalangeal joints in the lateral column.

Background: To evaluate the relationship between the pattern and severity of metatarsophalangeal (MTP) joint dislocation in the lesser toes and severity of joint destruction in rheumatoid forefoot deformities.

Methods: Participants comprised of 13 patients (16 feet) who underwent resection arthroplasty of the metatarsal head of the lesser toes for rheumatoid arthritis of the MTP joints. Correlations between preoperative radiographic findings and histological grades second to fifth metatarsal heads taken intraoperatively were analyzed.

Results: In 62 metatarsal heads, complete dislocation of the MTP joint in the lesser toes significantly resulted in severe joint destruction compared to mild or moderate dislocation (P < 0.05). The proportion of severe cartilage damage in MTP joints with complete dislocation was 100 % in the 5th MTP joint, 83.3 % in the 4th MTP joint, and 58.3 % in the 2nd and 3rd MTP joints. Moreover, complete dislocation of the MTP joints in the lateral column showed the most severe joint destruction compared to that in the medial column (P = 0.03).

Conclusion: Complete dislocation of the MTP joint in the lateral column is related to joint destruction in rheumatoid forefoot deformities.