Plantar plate radiofrequency and Weil osteotomy for subtle metatarsophalangeal joint instablity

Caio Nery, Fernando C. Raduan, Fernanda Catena, Tania Szejnfeld Mann, Marco Antonio Percope de Andrade, Daniel Baumfeld

To the present day, literature has only discussed how to treat extensive plantar plate and collateral ligament lesions, with gross joint subluxation and obvious clinical instability. The treatment options for early stages of the disease with minor injuries and subtle instabilities have not been described. The main purpose of this prospective study is to evaluate the efficacy of the combination of the arthroscopic radiofrequency shrinkage and distal Weil osteotomy in the treatment of subtle metatarsophalangeal joint instability. Prospective data (clinical, radiological, and arthroscopic findings) of 19 patients, with a total of 35 slightly unstable joints, was collected. The physical examination defined the hypothesis for plantar plate lesions (grades 0 and 1), which was confirmed during the diagnostic step of the arthroscopic procedure. Among our patients, 73 % were females and 63 % reported wearing high heels. The average age was 59 years and post-operative follow-up was 20 months. In the initial sample frame, 62 % of joints showed spread-out toes with increased interdigital spacing. The mean American Orthopedic Foot and Ankle Society score rose from 53 points pre-operatively to 92 points post-operatively and a visual-analog pain scale average value of eight points pre-operatively decreased to zero post-operatively. During the pre-operative evaluation, none of the patients had stable joints and over 97 % were classified as having grade 1 instability (<50 % subluxation). After treatment, 83 % of the joints became stable (degree of instability 0) and over 97 % were congruent. All studied parameters showed statistically significant improvements in the post-operative period (p < 0.001) showing the efficiency of the treatment in pain relief, while restoring the joint stability and congruity. Arthroscopic radiofrequency shrinkage in combination with distal Weil osteotomy promotes functional improvement, pain relief, and restores the joint stability in the plantar plate lesion grades 0 and 1.