Background The aim of the study is to identify those patients without improved pain sensation and functionality of the joint, thus with a potential necessity of re-intervention by using the evaluation of the PROMs (Oxford Hip Score, European Quality of Life Scale, EndoCert-Risk-Score). The task was to determine the value of the scores which represents the limit above/below, which a re-examination of the patient is necessary. Additionally, further secondary objectives such as influence of complications on scores, the percentage of questionnaire return and the quality of the provided data in the questionnaires were recorded to define minimal requirements on patientʼs response.
Material and Methods Members of the EndoCert certification committee developed a questionnaire for pre- (decision on treatment) and post-operative (discharge and 3-months follow-up) use. A total of 112 primary hip replacements and 25 hip revision arthroplasties, which were recruited from a centre of excellence for joint replacement (EndoProthetikZentrum der Maximalversorgung), were included in the study.
Results The return of questionnaires amounted to 80%. Quality of data in the questionnaires declined with BMI (≥ 25), ASA classification (≥ 3), age (≥ 65) and depended on the time point questioning. Based on the EndoCert risk score there was a significant improvement in the experience of pain postoperatively compared to pre-operation (p < 0.05). However, the functionality of the joint, as measured as the use of walking frames or crutches as well as the need for help from others, did not improve. The results revealed that there was no correlation between the incidence of complications and a detrimental score. It was furthermore shown that patient specific attributes, e.g. age or BMI, or perioperative performance (duration of operation) did not influence the likelihood of a complication.
Conclusion It was shown that Oxford Hip Score and EQ-5D were not negatively influenced by complication during hospital stay. The evaluation of the EndoCert risk score showed not improvement between pre- and post-operative values regarding function but revealed a significant pain relief. A further study is intended to evaluate the intensity of pain after three months as part of an extended systemic follow-up. This could provide further insights whether the EndoCert risk score is a suitable tool to identify unsuccessfully treated patients.