A Comprehensive Assessment of Various Outcome Scores to Evaluate Total Hip Arthroplasties

Many scoring systems have been developed that serve to evaluate outcomes following total hip arthroplasty (THA). However, most systems focus on specific aspects of a patient's recovery rather than investigating a broad spectrum of parameters, which prevent physicians from obtaining a sufficient impression of a patient's recovery. Therefore, we evaluated existing scoring systems to assess the outcome categories included and parameters of interest.

We examined all hip scoring systems currently available in the literature. The outcomes measured in each scoring system were sub-classified into one of four categories; subjective, objective, rehabilitative, and quality of life. We determined the number of scoring systems that incorporated each of these four categories and we assessed the most common parameters in each. The categories and individual parameters were assigned a relative weighted mean score based on how often they were incorporated, in an effort to determine their importance.

We identified 42 hip scoring systems consisting of 44 individual parameters, which were divided into the above four categories. Of the relevant scoring systems, 74% included subjective parameters, 31% included objective parameters, 90% included rehabilitative parameters, and 62% included quality of life parameters. The most commonly assessed subjective parameters include pain, stiffness, and general hip difficulty. The most commonly assessed objective parameters include general/combined ROM, flexion/extension, and abduction/adduction. The most commonly assessed rehabilitative parameters include the ability to walk, the ability to climb stairs, and the ability to reach to the floor. The most commonly assessed quality of life measures include the ability to use a car, performance of light domestic duties, and performance of heavy domestic duties. The category of rehabilitative practices carried the greatest weighted mean (49%) in hip scoring systems, followed by subjective (40%), quality of life (6%), and objective (5%). With regard to individual hip outcome parameters, pain carried the greatest weighted mean (23%), followed by the ability to walk and the ability to perform general activities (11% each).

Patient outcomes can be evaluated by the use of scoring systems in an effort to determine the effectiveness of THA in regaining function and improving quality of life. Determining the frequency and importance of parameters in current scoring systems may allow for a more accurate and purposeful assessment of post-operative function and patient satisfaction. Understanding what is evaluated in existing scoring systems may shed light on the future development of a comprehensive outcome questionnaire.