Cement augmentation of suture anchors in the proximal humerus during rotator cuff repair improves pullout strength: a systematic review

ImportanceRotator cuff pathology is a growing concern in the ageing population. If cement augmentation of suture anchors improves pullout strength, its application can potentially be applied in cases of poor bone quality to prevent anchor failure.ObjectiveTo evaluate the biomechanical benefits and fixation strength of cement-augmented versus non-augmented suture anchors in the proximal humerus during rotator cuff repair (RCR).Evidence reviewA systematic review of PubMed, Embase and Cochrane Library was performed to identify all published articles reporting on biomechanical analysis of suture anchors in the shoulder in a cadaveric model. Inclusion criteria required fresh-frozen specimens, placement in the footprint of the proximal humerus, and comparative assessment of fixation constructs with or without polymethylmethacrylate (PMMA) or bioabsorbable composite cement augmentation. Biomechanical testing procedure, cement augmentation method and pullout force were assessed.FindingsAfter review of 105 abstracts, seven full manuscripts met inclusion criteria. Six of seven studies reported statistically significant differences in mean pullout force between augmented (three PMMAs, three composites, one PMMA vs composite) and non-augmented anchors. Of two studies evaluating cycles to failure, both found a significant increase in the augmented versus non-augmented anchors. Of two studies stratifying by anchor position, both investigations identified significant differences in mean pullout strength between augmented and non-augmented anchors at the posteromedial and anterolateral anchor positions.Conclusions and relevanceCement augmentation of suture anchors in cadaveric humeri for RCR improves pullout strength regardless of cement type used or anchor position. Cement augmentation may provide a viable option for future clinical application.Level of evidenceIV, systematic review.