Abstract
CATEGORY: Arthroscopy; Midfoot/Forefoot INTRODUCTION/PURPOSE: Refractory pain to the fourth and fifth tarsometatarsal (TMT) joint is a source of disability and functional impairment. The etiology of fourth and fifth TMT joint pain may be attributed to injury, post-traumatic arthritis, or arthrofibrosis, however, the principal pathologies associated with pain in the absence of arthritis are not well elucidated. The purpose of this study is to characterize arthroscopic pathology associated with chronic refractory pain to the fourth and fifth TMT joints with and without arthritis. METHODS: We retrospectively examined 25 patients that underwent arthroscopic surgery of the fourth and fifth TMT joints for refractory pain at our academic institution between 2015 - 2020. Patients were placed in supine position, thigh tourniquet placed, prepped and draped in standard sterile fashion. The fourth and fifth TMT joints were accessed medially through a portal between the third and fourth TMT joint and laterally through a portal lateral to the fifth TMT joint. A 30° 2.5mm arthroscope was used as well as 2.5mm aggressive soft tissue shaver. Intraoperative fluoroscopy was use to confirm location of the arthroscope and shaver. The intraoperative findings were recorded into the medical record. We used the Outerbridge classification for chondral lesions, the Kellgren Lawrence (KL) radiographic classification for osteoarthritis, and described intraarticular pathologies as acute hypertrophic synovitis, chronic synovial fibrosis, hyaline bands, meniscoid bodies, loose joint bodies, arthrofibrosis. RESULTS: Twenty-three fourth TMT joints and 26 fifth TMT joints, in 25 patients, underwent arthroscopic surgery for refractory pain. Average age was 62.6+-8.3 years. Average body mass index was 31.0+-5.0 kg/m(2). All patients had pain with piano-key test. Twelve patients with arthritis to first through third TMT joints and eight patients to second through third TMT joints required arthrodesis. Approximately, 71.4% of TMT joints presented with radiographic evidence of arthritis and 28.6% of TMT joints were absent of radiographic signs of arthritis. The soft tissue pathology observed in patients without radiographic evidence of arthritis was arthrofibrosis (87.5%), chronic synovial fibrosis (75.0%), and acute hypertrophic synovitis (62.5%). Frequency plot of soft tissue pathologies, Outerbridge classification and KL radiographic classification for arthritis are shown in Figure 1. CONCLUSION: This is the first study to report arthroscopic findings associated with refractory pain of the fourth and fifth TMT joints with and without arthritis. These findings provide information regarding pathologies associated with fourth and fifth TMT joints pain and subsequent treatment.