RSA in Spine: A Review

STUDY DESIGN: Systematic review of literature. OBJECTIVES: This systematic review was conducted to investigate the accuracy of radiostereometric analysis (RSA), its assessment of spinal motion and disorders, and to investigate the limitations of this technique in spine assessment. METHODS: Systematic review in all current literature to invesigate the role of RSA in spine. RESULTS: The results of this review concluded that RSA is a very powerful tool to detect small changes between 2 rigid bodies such as a vertebral segment. The technique is described for animal and human studies for cervical and lumbar spine and can be used to analyze range of motion, inducible displacement, and fusion of segments. However, there are a few disadvantages with the technique; RSA percutaneous procedure needs to be performed to implant the markers (and cannot be used preoperatively), one needs a specific knowledge to handle data and interpret the results, and is relatively time consuming and expensive. CONCLUSIONS: RSA should be looked at as a very powerful research instrument and there are many questions suitable for RSA studies.