Suprascapular Nerve Decompression in Addition To Rotator Cuff Repair: A Prospective, Randomized Observational Trial

Abstract Background Tear and retraction of the supra (SS)- and infraspinatus (IS) musculotendinous units and /or their repair may be associated with traction damage to the suprascapular nerve, potentially responsible for pain or weakness of the rotator cuff (RC). Arthroscopic release of the transverse scapular ligament at the suprascapular notch has been advocated to prevent or treat suprascapular nerve impairment associated with RC retraction and / or repair. The effect of this procedure on preoperative normal nerve function is, however, not well studied. We hypothesize that (1) decompression of the suprascapular nerve without preoperative pathological neurophysiological findings does not improve clinical or imaging outcome and (2) suprascapular decompression does not measurably change suprascapular nerve function. Methods Nineteen consecutive patients with an MR-arthrography documented RC tear involving SS and IS but normal preoperative Electromyography (EMG) / Nerve Conduction Studies (NCS) of the SS and IS, were enrolled in a prospective, controlled trial involving rotator cuff repair with or without suprascapular nerve decompression at the suprascapular notch. Nine patients were randomized to undergo, ten not to undergo a decompression of the suprascapular nerve. Patients were assessed clinically (Constant score, mobility, pain, strength, subjective shoulder value), with MRI and neurophysiology preoperatively and at 3- and at 12-months follow-up. Results There was no clinically relevant difference between the release and the non-release group in any clinical parameter at any time point. At MRI there was a slightly greater increase of fatty infiltration of the IS in the release group without any other differences between the two groups. Electromyographically, there were no pathological findings in the non-release group at any time point. Conversely, three out of the nine patients of the release group showed pathological EMG findings at three months, which at twelve months had recovered fully in two but only partially in the third patient. Conclusion In the presence of normal EMG findings, suprascapular nerve release added to arthroscopic RC repair is not associated with any clinical benefit, but with electromyographically documented, postoperative impairment of nerve function in one out of three cases. Suprascapular nerve release does therefore not seem to be justified as an adjunct to RC repair if preoperative EMG findings document normal suprascapular nerve function. Based on these findings, the ongoing prospective randomized trial was terminated.