Orthopedic & Muscular System: Current Research
Open Access

Reliability of Tonnis classification in early hip arthritis: A useless reference for hip-preserving surgery

9^th Orthopedics & Rheumatology Annual Meeting & Expo

July 12-13, 2017 Chicago, USA

Marius Valera P S, Natalia Ibanez, Rogelio Sancho and Marc Tey

Hospital de Sant Pau, Spain

Scientific Tracks Abstracts: Orthop Muscular Syst

Abstract :

Background: The Tonnis classification is widely accepted for grading hip arthritis but its usefulness as a reference in conservative hip surgery is yet to be demonstrated. Purpose: We aimed to evaluate reproducibility and validity of the T���¶nnis classification in early stages of hip osteoarthritis and thus determine whether it is a reliable reference for conservative hip surgery. Methods: We prospectively examined 117 hip X-rays from two groups of patients below 55 years: A group of 31 candidates for hip conservative surgery and a control group of 30 asymptomatic subjects. Three orthopedic surgeons with different levels of experience each graded arthritis twice using the Tonnis classification. Intra- and inter-observer reproducibility was analyzed using Kappa index and graded following Landis and Koch classification. The scale was validated using pain as an external variable. Results: Kappa values for interobserver reproducibility were slight or fair (range 0.173-0.397). Kappa values for intraobserver reproducibility were fair (range 0.364- 0.397). Confusion between grades 1 and 0 was the most frequent cause of intra- and interobserver disagreement (76.3% and 73.01% of the non-concordant observations respectively). The confidence interval analysis showed observer experience did not affect reproducibility. Although symptomatic hips showed significantly higher scores than asymptomatic (Mann-Whitney, p<0.001) validity of the classification could not be demonstrated. Conclusions: The T���¶nnis classification is a poor method to assess early stages of hip osteoarthritis. These findings suggest its routine use in therapeutic decision-making for conservative hip surgery should be reconsidered.

Biography :

Marius Valera has completed his Doctor of Medicine from Universitat Autònoma de Barcelona in 1992. After that he completed his Residency & Fellowship from Hospital de Sant la santa Creu i Sant Pau in Barcelona. Currently he is working as Consultatn of the Hip Surgery at Hospital de Sant Pau & Professor at Universit at Autónoma de Barcelona.

Email: mvalera@santpau.cat