title: Shoulder muscle function in frozen shoulder syndrome patients following manipulation under anesthesia: a 6-month follow-up study.
abstract: BACKGROUND
  The present study evaluates changes in shoulder muscle function in patients with frozen shoulder syndrome (FSS) following manipulation under general anesthesia (MUA).
  
  
  METHODS
  Fifteen FSS patients with mean (±SD) age of 53.6±9.7 years were included in this study. Isometric endurance of the shoulder muscles was characterized by time and net impulse (NI), which were assessed with the patient holding a weight in the hand until exhaustion. Fatigability of the deltoid and trapezius muscles during isometric endurance test was assessed by electromyogram power spectrum median frequency (MF) slope per minute. Patients were also screened for daytime pain. Data were collected before MUA, and at 1 and 6 months postoperatively.
  
  
  RESULTS
  Six months postoperatively, the MF slope for the trapezius and deltoid muscles of the involved and uninvolved shoulders did not differ (P>0.05), whereas NI remained lower and endurance time was longer (P<0.05). Shoulder pain was reduced as compared to preoperative levels (on visual analog scale) 1 and 6 months postoperatively (P<0.05).
  
  
  CONCLUSIONS
  In patients with FSS, the fastest improvements in shoulder muscle NI, fatigability and pain take place in the first month after MUA; 6 months after MUA, however, NI and endurance time remained impaired for the involved shoulder. Physiotherapy should pay more attention to muscle function recovery.
  
  
  METHODS
  Level III, prospective follow-up study.
authors.affiliation: Institute of Exercise Biology and Physiotherapy, University of Tartu, Tartu, Estonia; Centre of Behavioral and Health Sciences, University of Tartu, Tartu, Estonia. Electronic address: jelena.sokk@ut.ee.
authors.forename: J
authors.initials: J
authors.lastname: Sokk
authors.forename: H
authors.initials: H
authors.lastname: Gapeyeva
authors.forename: J
authors.initials: J
authors.lastname: Ereline
authors.forename: M
authors.initials: M
authors.lastname: Merila
authors.forename: M
authors.initials: M
authors.lastname: Pääsuke
mesh_terms: D000704:Analysis of Variance; D000772:Anesthesia, Local; D015331:Cohort Studies; D004576:Electromyography / Q000379:methods; D005081:Exercise Therapy / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008349:Manipulation, Orthopedic / Q000379:methods*; D008875:Middle Aged; D018763:Muscle Fatigue; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010147:Pain Measurement; D016059:Range of Motion, Articular / Q000502:physiology*; D020127:Recovery of Function; D018570:Risk Assessment; D012720:Severity of Illness Index; D019534:Shoulder Impingement Syndrome / Q000175:diagnosis / Q000503:physiopathology* / Q000534:rehabilitation* / Q000601:surgery; D013997:Time Factors; D016896:Treatment Outcome
keywords: Frozen shoulder syndrome; Isometric endurance; Isometric working capacity; Rehabilitation