Postoperative New-Onset Pseudoparalysis: A Retrospective Analysis of 430 Consecutive Arthroscopic Repairs for Large to Massive Rotator Cuff Tears.

BACKGROUND

The authors have sometimes encountered postoperative new-onset pseudoparalysis (PONP) after arthroscopic repair for large to massive rotator cuff tear (ARCR). As there are insufficient data regarding PONP, the authors aimed to determine whether such a condition is characterized by obvious risk factors, as well as to assess the conditions under which it can be reversed.

PURPOSE

To evaluate the predictors of PONP development after ARCR and its reversal and to integrate these predictors into a scoring system that can be applied in clinical practice.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

The authors retrospectively analyzed 430 consecutive ARCRs performed between March 2010 and May 2016. Patients were stratified according to the occurrence of PONP. To determine the risk factors of PONP, the authors compared the PONP and control groups (patients who did not experience PONP) in terms of demographic, clinical, and operative characteristics. Results were expressed in terms of odds ratios (ORs).

RESULTS

The incidence of PONP was 6.0% (26 of 430). Predictors of PONP included torn subscapularis (OR, 7.875; 95% CI, 1.780-34.956; P = .007), ≥30-mm retraction of the torn supraspinatus (OR, 4.657; 95% CI, 1.537-14.203; P = .007), age ≥65 years (OR, 3.865; 95% CI, 1.465-10.040; P = .006), and preoperative stiffness (OR, 2.954; 95% CI, 1.212-7.159; P = .017). The reversal rate of PONP was 65.4% (17 of 26), and the mean time to PONP reversal was 10 months. The occurrence and reversal of PONP were not related to retear. Fatty infiltration of the supraspinatus lower than Goutallier grade 3 was the sole predictor of reversal (OR, 22.000; 95% CI, 1.857-260.648; P = .014).

CONCLUSION

Although the incidence of PONP after ARCR was low (6.0%), the risk of PONP was higher in patients with a torn subscapularis, larger supraspinatus tear size, older age, and preoperative stiffness. The mean time from PONP onset to reversal was 10 months, and PONP reversal was affected solely by fatty infiltration of the supraspinatus. Therefore, surgeons should consider the risk for PONP and attempt to identify high-risk patients before rotator cuff repair.