Influence of Tönnis grade on outcomes of arthroscopy for FAI in athletes: a comparative analysis

Abstract

Based on a previously reported study, it is hypothesized that To nnis 2 changes may not be a harbinger of poor results. The purpose is to report outcomes comparing To nnis 2 changes to those with To nnis 0&1 changes. Previously published outcomes (modified Harris Hip Score and return to sport) among 200 consecutive athletes undergoing arthroscopic correction of femoroacetabular impingement with minimum 1-year follow-up were correlated with the To nnis grade. Independent variables of gender and age were also evaluated. Average age was 28.6 years (range 11-60), with 148 males and 52 females. The average improvement was To nnis 0 23.1 points (n 37), To nnis 1 20.6 points (n 113) and To nnis 2 16.4 points (n 48). A trend (P 0.055) towards lower scores with increasing To nnis grade was not statistically significant. There was both statistically (P < 0.01) and clinically (>8 patients) significant improvement across all To nnis grades, and there was no statistically significant difference between To nnis 0 and 1 compared with To nnis 2 (P 0.078). The percent that returned to sport was as follows: To nnis 0 95%, To nnis 1 92% and To nnis 2 85%. A trend (P 0.098) towards lower rates of return to sport with increasing To nnis grade was not statistically significant, and there was no statistically significant difference between To nnis 0 and 1 compared with To nnis 2. Within each grade, there was no correlation with age, such that increasing age did not reflect lower scores. There was also no correlation with gender. Statistically and clinically successful outcomes can be encountered among athletes with To nnis 2 radiographic features.