Clinical and structural results of partial supraspinatus tears treated by subacromial decompression without repair

Patients with primary impingement and articular sided partial tears of the supraspinatus are often treated by subacromial decompression without repair, if the extent of the tear is estimated to be below 50% of tendon thickness. It has been questioned whether repair of these cuff lesions is necessary, because these tears could progress to full thickness tears with deteriorating clinical results. Our hypothesis was that subacromial decompression without repair of the supraspinatus tendon leads to significant clinical improvement for patients with grade I and II articular sided tears without progression to a full thickness tear on a regular basis. 46 consecutive patients (av. Age 59.2 years, range 33-76.6 years) were retrospectively reviewed after an average follow up of 50.3 months (36-86 months). 26 patients (43.5%) had a grade I tear according to Ellman, which was left alone, 20 patients suffered from a grade II tear, which was debrided. Clinical outcome was assessed with the ASES Score and ultrasound evaluation was performed on all patients to detect possible progression to a full thickness tear. The average ASES Score significantly improved from 37.4 to 86.6 points (p < 0.0001). The mean postoperative Constant Score was 87.6 points. Only three patients (6.5%) progressed to a full thickness tear detectable on ultrasound examination. Only one of these patients had a poor result with an ASES Score of 35 points, the other two were very satisfied and had an ASES score above 90 points. 8 patients showed no more signs of partial tearing on ultrasound and these patients had an average ASES Score of 93.1 points. Overall clinical outcome was rated excellent in 35 cases (76.1%), good in 5 (10.9%), average in 2 (4.3%) and poor in 4 (8.7%). Our results indicate that good and excellent results can be achieved mid- to long term by acromioplasty without repair of the rotator cuff in articular sided partial tears grade I and II. These results reach almost 95% of the value of a healthy shoulder. A better result on ultrasound examination was associated with a superior clinical outcome, while progression to a full thickness tear was rare.