Objective: Pilot study to demonstrate and explain the enabling effects of headstand and chair-supported headstand in the clinical management of patients with rotator cuff tear, also known as rotator cuff syndrome (RCS).
Design: Prospective, unblinded single exposure study with repeated-measures design.
Setting: Private outpatient medical office.
Participants: Ten patients meeting clinical criteria for rotator cuff syndrome (RCS). MRI confirmed severe or total thickness tear of either the supraspinatus or infraspinatus muscles or both.
Intervention: Participants were taught a version of shîrshâsana (headstand), and remained in the inverted position for 30 seconds. Participants practiced the inversion for 30 seconds once a day for six weeks thereafter.
Data: Patients were tested for maximal voluntary abduction and flexion of the neutrally positioned arm, then rated their pain on maximal abduction before and after being taught a version of headstand, and at a six-week follow-up.
Outcome Measures: Immediate (post-headstand) and six-week change in function, measured by active range of abduction and flexion of the neutrally positioned arm. Immediate (post-headstand) and six-week change in pain during abduction, measured by a 10-point visual analogue scale (VAS).
Results: Mean voluntary abduction and flexion increased from 85 degrees each to 158 degrees and 162 degrees respectively. Mean VAS pain rating during abduction fell from 4.8/10 to 1.2/10.
Further Investigation: Electromyographic (EMG) interference pattern changes showed that the subscapularis, anterior and lateral deltoid, and rhomboid major were significantly more active electrophysiologically during headstand, and in abduction and flexion following headstand, than in abduction and flexion performed prior to headstand. MRI confirmed subscapularis activation in post-headstand shoulder abduction.
Conclusions: Headstand and a chair-supported version of headstand appear to improve function in the upper extremity after rotator cuff injury. EMG suggests that the subscapularis holds down the head of the humerus while the deltoid abducts the shaft. Using these two muscles together for abduction and flexion, in place of the supraspinatus, appears to be learned through brief exposure to a version of headstand.