Acromioplasty reduces critical shoulder angle in patients with rotator cuff tear

Abstract

Critical shoulder angle (CSA) is the angle between the superior and inferior bone margins of the glenoid and the most lateral border of the acromion and is potentially affected during a rotator cuff tear (RCT). Acromioplasty is generally performed to rectify the anatomy of the acromion during RCT repair surgery. However, limited information is available regarding the changes in the CSA after anterolateral acromioplasty. We hypothesized that CSA can be decreased after anterolateral acromioplasty. Data were retrospectively collected from 712 patients with RCTs and underwent arthroscopic rotator cuff repair between January 2012 and December 2018, of which 337 patients were included in the study. The presurgical and postsurgical CSA were then determined and compared using a paired samples t test. Because previous study mentioned CSA more than 38 degrees were at risk of rotator cuff re-tear, patients were segregated into two groups: CSA < 38° and CSA ≥ 38°; these groups were compared using an independent-samples t test. These 337 participants (160 male and 177 female) presented a CSA of 38.4° ± 6.0° before anterolateral acromioplasty, which significantly decreased to 35.8° ± 5.9° after surgery (P < .05). Before surgery, 172 patients were present in the CSA ≥ 38° group and 57 were preset in the CSA < 38° group after surgery. The CSA decreased significantly in the CSA ≥ 38° group rather than in the CSA < 38° group (P < .05). In conclusion, the CSA can be effectively decreased through anterolateral acromioplasty, and this reduction in the CSA is more significant among individuals with CSA ≥ 38° than among those with CSA < 38°, indicating that acromioplasty is recommended along with RCT repair especially among individuals with a wide presurgical CSA.

Does the critical shoulder angle decrease after acromioplasty? A systematic review and meta-analysis

“…Anterolateral acromioplasty was described in 2 studies. Lin et al [ 25 ] reported that 337 participants presented with a mean CSA of 38.4° ± 6.0° before surgery, which significantly decreased to 35.8° ± 5.9° after anterolateral acromioplasty ( p < 0.05). Katthagen et al [ 17 ] reported that anterolateral acromioplasty decreased the CSA by a mean of 1.4° (95% CI 0.8°, 1.9°).…”

Critical Shoulder Angle in Patients With Cuff Tears

“…48,49 The role of acromioplasty in the setting of RCT repair has been widely discussed. Lin et al 50 showed that anterolateral acromioplasty effectively reduced CSA and this is more significant among individuals with CSA ≥ 38 degrees than among those with CSA < 38 degrees. Conversely, Thiesemann et al 51 concluded that anterolateral acromioplasty did not result in a significant change in the CSA; a significant reduction was observed in the case of CSA > 35 degrees but not to normal values.…”