Clinical and surgical aspects of treatment of degenerative and traumatic rotator cuff tears

Pain caused by rotator cuff pathology or tear is a major source of discomfort and dysfunction in the shoulder joint. The prevalence of rotator cuff tear increases with age and also as the workforce becomes older. The number of otherwise healthy elderly individuals with high demands on functionality and quality of life in the society is also increasing. A successful rotator cuff repair leads to a good shoulder function, and excellent patient satisfaction however, the failure rate is still considerably high, especially in multi tendon and chronic tears in the elderly, despite the advances in surgical techniques. The overall aim of this thesis was to study factors, which might improve the result of surgical treatment. Study 1) The purpose of this retrospective cohort study was to investigate the result of surgery after traumatic rotator cuff tear regarding the time delay to surgery after injury. Seventy-three patients (75 shoulders) were retrospectively examined with Magnetic Resonance Imaging (MRI) and functional outcomes at least one year after the surgery. The results were compared in patients who had surgery earlier or later than three months after their injury. No significant difference was found between the groups. The conclusion was that if repair was possible the timing should not impact surgical decision. Study 2) The aim of this validation of outcomes instruments study was to validate the Swedish version of the Western Ontario Rotator Cuff index (WORC) in evaluation of treatment outcome for subacromial disease including rotator cuff tears. In total, 114 patients were included prospectively in this study. The WORC was tested against WOOS, Oxford Shoulder Score, Constant-Murley Score and EQ-5D. The results showed that the Swedish version of WORC was valid, reliable and responsive in evaluation of this group of patients. Study 3) The purpose of this retrospective cohort study was to find factors on preoperative MRI prior to rotator cuff surgery, which might predict the outcome. In this study sixty-two pre- and postoperative MRI were compared. The results showed that preoperative tendon retraction of more than 40 mm, muscle atrophy according to Goutallier classification grade 3- 4 might predict a worse surgical outcome, with a fivefold increase in the risk for a re-rupture. A prevention of progression of muscle atrophy and fatty degeneration was found in the successfully repaired shoulders but also an improvement in 8-11% of all the cases. This result favors surgery when a repair is technically possible. Study 4) The aim of this prospective randomized controlled patient-blinded clinical trial with including fifty-eight patients was to investigate whether a synthetic patch might improve the result after rotator cuff surgery. In half of the cases the repair was augmented with a synthetic patch, Artelon®. Assessment was made by serial ultrasound during the first three months post-surgery. There were no differences identified in any of the outcome measures including functional scores and MRI at 12 months follow-up. Based on this result we would not recommend the routine use of a synthetic patch in cuff repair. However, the use of Artelon® was safe and leads to good function and patient satisfaction comparable to the conventional repair. The results out of this thesis support the fact that the timing after traumatic rotator cuff tears is not a considerable factor in decision-making regarding surgical repair. The Swedish version of WORC is reliable and useful in assessing the outcome in subacromial disease including rotator cuff tears. There are findings on preoperative MRI that may predict the result of surgery in rotator cuff repair. The use of Artelon®, a synthetic patch augmentation, in rotator cuff repair is safe but not superior to traditional repair