Rotator cuff repair failure in vivo: a radiostereometric measurement study

Background: The prevalence of failure among repairs of the rotator cuff is well known, but very few objective data exist regarding either the scale or timing of this complication. The aim of this study was to use a previously validated modified technique of roentgen stereophotogrammetric analysis to monitor the behavior of the rotator cuff after repair to establish at what point failure may occur. Materials and methods: A series of 10 patients had metal beads and wire sutures embedded into the humeral greater tuberosity and supraspinatus tendon, respectively, during open cuff repair procedures. Roentgen stereophotogrammetric analysis imaging of the repaired rotator cuffs was performed at set intervals during the first year after surgery. Results: The mean distance between the tendon and bone markers did not increase significantly between the time of surgery and 3 to 4 weeks. There was then a significant increase of 7.0 mm in the distance between the tendon and bone markers, with the largest increase occurring between 3 to 4 weeks and 12 to 14 weeks after surgery, as well as a further small but significant increase of 1.7 mm between 12 to 14 weeks and 1 year. These results were compared with clinical examination and ultrasound findings. Conclusion: Most tendon marker movement was seen during the most intensive period of physiotherapy, in the second and third months after surgery. Significantly more movement was seen in the tendon markers of those patients in whom the repair failed. Level of evidence: Level I, Prospective Cohort, Prognosis Study. (C) 2011 Journal of Shoulder and Elbow Surgery Board of Trustees.