Clinical Effect Of Suprascapular Nerve Decompression At The Spinoglenoid Notch In Patients With Posterosuperior Massive Rotator Cuff Tears

Objective:To investigate the clinical effect of suprascapular nerve decompression in patients with posterosuperior massive rotator cuff tears,and to explicit the effect of suprascapular nerve decompression in order to guide the surgical planning for such patients..Methods:Ten formalian fixed adult cadavers(twenty shoulder joints)were selected to dissect the course of the transverse subscapular ligament,confirm its existence rate and measure the shortest distance between the suprascapular nerve and the edge of scapula glenoid(specimens from the human anatomy laboratory of Qingdao University).Retrospective analysis the 32 patients with posterosuperior massive rotator cuff tears combined with suprascapular nerve injury from January 2016 to January 2020 in the Affiliated Hospital of Qingdao University.Patients were divided into two groups according to whether or not they underwent suprascapular nerve decompression at the spinoglenoid notch.The average age of patients was 57.62 ± 10.12(45～74)years old.In the releasing group,before the rotator cuff repair,the soft tissue adhesions around the neurovascular bundle were released,and the inferior transverse scapular ligament was cutted.UCLA scores and VAS scores were recorded preoperatively,6 months postoperatively,and 12 months postoperatively.12 months after surgery,The shoulder MRI was performed to assess the healing of rotator cuff according to the patient’s condition changes.The electrophysiological examination was performed 6 months after surgery to assess the recovery of suprascapular nerve.The range of motion of shoulder joint was recorded to comprehensively evaluate the function of shoulder joint and surgical effect.Patients underwent routine outpatient reexamination at 1month,3 months,6 months and 12 months after surgery,and reexamination at any time according to their condition.Results:Anatomically,the existence rate of inferior transverse ligament of scapula was 70%.The shortest distance between the suprascapular nerve and the edge of scapula glenoid was17.73 ± 1.61 mm.The shoulder joint function of all patients was improved significantly after operation.At the 12-month follow-up,the VAS score in the releasing group decreased from 7.42 ± 0.67 preoperatively to 2.00 ± 0.74,and UCLA score increased from 11.17 ±1.79 preoperatively to 29.33 ± 4.75.The active flexion,abduction and external rotation of shoulder increased from 50.83 ± 16.89°,50.42 ± 20.94° and 12.50 ± 6.91° to 148.83 ±22.51°,150.42 ± 31.22° and 56.67 ± 8.62°,respectively.In the nonreleasing group,VAS score decreased from 7.83 ± 0.83 preoperatively to 2.08 ± 0.67,and UCLA score increased from 11.17 ± 1.70 preoperatively to 27.83 ± 5.61.The active flexion,abduction and external rotation of the shoulder increased from 51.67 ± 17.36°,49.83 ± 16.82° and 14.17 ± 8.48°to 146.25 ± 25.24°,148.33 ± 32.29° and 53.75 ± 7.72°,respectively.There was no statistical significance in UCLA score,VAS score and range of motion of shoulder between the two groups 12 months after surgery.The EMG of all patients was reexamined 6 months after surgery.No spontaneous potential was found in the supraspinatus muscle and the infraspinatus muscle,and the suprascapular nerve function recovered.All patients were reexamined for shoulder MRI within 12 months after surgery,and 4 patients in each group had re-tear,with a re-tear rate of 25%(4/16).Conclusion:For the patients with posterosuperior rotator cuff tear and suprascapular neuropathy,suprascapular nerve decompression at the spinoglenoid can not further improve the shoulder function and healing rate of rotator cuff.For such patients,we can only do arthroscopic rotator cuff repair when surgical treatment is needed.