10 December 2021

Excellent clinical results of the A2® hip stem system in studies

The cementless A2® short stem convinces with promising results in the multicentre PMCF (“Post-Market Clinical Follow-up”) study and shows an excellent balance on the clinical performance of the product in the evaluations after the first postoperative year.

A total of 173 patients were included in the study and were fitted with a cementless A2® short stem in five different centres. 163 patients attended the follow-up appointment after three months. 153 patients could already be examined after the first year postop. The clinical results and the patient-specific questionnaires on subjective satisfaction were evaluated.

Results

All stems are still under follow-up, no hip stem revision had to be performed so far. Regarding the clinical Harris Hip Score “HHS”, the recorded results after both 3 months and one year, compared to the literature (Banaszkiewicz, 2014), can be considered excellent with 96.7 ± 4.5 points out of a possible 100. Compared to the preoperative HHS of 43.8 ± 12.8 points, the value has thus improved by more than double. The evaluation of the HOOS-PS score also shows a very comparable trend in patient satisfaction. From a preoperative value that was clearly below the reference value (reference values from Rosenlund et al., 2017), the postoperative values have risen sharply and are clearly above the reference value.

The good results are confirmed by another study looking at the migration of the cementless A2® short stem (RSA study) with 60 patients. In this study, the postoperative six-month evaluations have almost been completed and also show excellent clinical results; the investigations for one and two years postoperatively are currently ongoing.

In addition, another multicentre study with at least 120 patients has been started. This will be carried out on the cemented A2® short stem variant. First results are expected in the middle of next year.

Literatur

[1] Paul A. Banaszkiewicz, Deiary F. Kader (2014); „Traumatic Arthritis oft he Hip After Dislocation and Acetabular Fractures: Treatment by Mold Arthroplasty: An End-Result Study Using a New Method of Result Evaluation“; in Classic Papers in Orthopaedics; Paul A. Banaszkiewicz; Springer-Verlag London; S. 14; https://doi.org/10.1007/978-1-4471-5451-8

[2] in Referenz zu mean HOOS-PS Score (Fig. 2): Signe Rosenlund, Leif Broeng, Anders Holsgaard-Larsen, Carsten Jensen & Søren Overgaard (2017); „Patient-reported outcome after total hip arthroplasty: comparison between lateral and posterior approach“; in Acta Orthopaedica, 88:3, S. 239-247, DOI: 10.1080/17453674.2017.1291100