The correlation between biomechanical experiments and clinical studies in orthopedics: a systematic review.

PURPOSE

To evaluate the clinical relevance of biomechanical experiments by conducting a systematic review of orthopedic studies that compared treatments with both a biomechanical experiment and a clinical study.

METHODS

A systematic search of MEDLINE/PUBMED was performed to identify orthopedic studies that included both a biomechanical experiment and a clinical study to compare treatments. The association between a difference in the outcome of the biomechanical experiment and a difference in the outcome of the clinical study was evaluated.

RESULTS

There were 23 studies that were included. The orthopedic specialty of the studies included trauma (n = 17), pediatric trauma (n = 2), sports (n = 2), and hand (n = 1). The anatomic areas of each study included the hip/femur (n = 11), shoulder/humerus (n = 3), elbow/forearm (n = 2), knee/tibia (n = 3), ankle/foot (n = 2), pelvis/acetabulum (n = 1), and hand (n = 1). The biomechanical experiments involved cadavers (n = 14), synthetic bone (n = 5), finite element analysis (n = 3), and animals (n = 1). The biomechanical experiment from each study, compared to the clinical study, was more likely to report a difference in outcomes (82.6% (19/23) vs. 30.4% (7/23), p = 0.0008). The findings of the biomechanical experiment and the clinical study were in agreement in 43.4% (10/23) of the studies. Studies that reported a difference in the biomechanical outcome, compared to those that did not, were not more likely to report a difference in the clinical outcome (31.6% (6/19) vs. 25.0% (1/3), p = 1.0).

CONCLUSIONS

The outcomes of biomechanical experiments did not correlate with clinical study outcomes. Considering these findings, the utility of biomechanical experiments in orthopedics should be reexamined.

LEVEL OF EVIDENCE

Level 3.