Hypothesis: Range of motion and stability assessment in outpatient clinics are not usually true, comparative study with examination under anesthesia (EUA) is crucial for treatment of the shoulder.
Methods: We investigated 188 shoulders from 2008 to 2010, including 59 female and 129 male. The average age was 50.7 ± 17.6 years old. EUA was performed with the patients in the beachchair position. Range of motion was estimated by goniometer and stability was rated as grade from 0 (normal) to 3 (dislocation).
Results: Range of motion of the healthy shoulder and mobility (instability) decreases with aging.
Females have a larger range of motion than males and dominant-side shoulder have a larger range of motion than non-dominant. Patients with anterior instability have a smaller range of internal and external rotation at 90 degrees abduction at outpatient clinic than EUA (14.5 ± 18.8 v/s 34.1 ± 12.8 degrees). Patients with cuff tear have a smaller range of internal rotation at 90 degrees abduction at outpatient clinic than EUA (7.6 ± 12.8 v/s 22.0 ± 17.1 degrees and 84.8 ± 16.3 v/s 98.6 ± 17.3 degrees, respectively).
Discussion: These result suggest that apprehension and pain at particular positions of the arm induce a protective reaction and consequently reduce the range of motion at outpatient clinic. Comparative study with EUA is very crucial for treatment of the shoulder.
