Measuring hip outcomes: common scales and checklists

Assessing the outcomes of patients following surgical interventions is a challenging task. Traditionally the end results of joint replacement were based on morbidity/mortality rates and operative complications. The modern approach to outcomes following Orthopaedic surgery has shifted from the success or failure of implants towards patient satisfaction and the quality of life achieved. The aim of this paper was to identify and analyse the common scoring systems present in the medical literature for evaluating outcomes after hip interventions.

A pub-med search was performed using terms 'scoring system, functional outcomes, hip joint'. Specific limitations and exclusion criteria were used and the reference lists of the articles included in the study were subjected to further analysis for identification of additional relevant papers.

293 articles were identified of which 40 met the inclusion criteria. The outcome measures were divided into: (i) hip specific outcomes, (ii) disease-specific measures and (iii) generic quality of life measures. Based on our analysis, we would recommend a combination of the hip specific Oxford Hip Score (OHS) and the disease specific WOMAC score. The OHS is quick and easy to complete, has a very high response rate and is free from clinician bias. On the other hand, the majority of hip pathology is related to degenerative disease, thus making the WOMAC the most appropriate measure to use. Where comparison between different conditions is required, then an additional generic quality of life (QOL) score, such as EQ5D, that can enable comparisons in cost-effectiveness term can be used.

The ideal outcome measure should be one that is specific for the hip joint, possesses a generic component and takes into consideration co-morbidities and the use of walking aids. Although many validated generic measures exist, additional validation studies, including the OHS, are desirable to evaluate all the hip specific measures of outcome.