The purpose of this study was to determine whether comorbid factors
influence the results of self-assessment instruments completed by
patients with idiopathic adhesive capsulitis of the shoulder. We
hypothesized that an increased number of comorbidities would be
correlated with greater pain and worse function as measured by general
and shoulder-specific outcome tools.
One hundred consecutive patients with phase-II adhesive capsulitis
were prospectively evaluated with use of a general health questionnaire,
a visual analog pain scale, the Simple Shoulder Test, the Disabilities
of the Arm, Shoulder and Hand questionnaire, and the Short Form-36.
There were seventy-one women and twenty-nine men, with a mean age
of fifty-two years (range, thirty-six to eighty-two years). Comorbidities
included medical factors (e.g., diabetes and heart disease) and
social factors (e.g., tobacco use and pending litigation). Linear
regression analysis was performed to determine correlations between
the number of comorbidities and the results of the questionnaires.
Patients with more comorbidities had significantly lower scores
on the Disabilities of the Arm, Shoulder and Hand Questionnaire
(p = 0.0005) and the Short Form-36 subscale of physical function
(p = 0.0009) as well as poorer scores on the Simple Shoulder Test
and the Short Form-36 subscales of physical role, social function,
emotional role, and mental health. Although there was no correlation
between increased comorbidity and pain as measured on the visual
analog scale, the comfort/pain subscale of the Short Form-36 showed
a significant correlation with increased comorbidity (p = 0.004).
Idiopathic adhesive capsulitis is a debilitating condition. Comorbid
factors have a significant effect on the pain and dysfunction (as
measured on shoulder-specific and general health instruments) experienced
by patients with this disorder. These findings can be applied to
the evaluation of these patients and may help to identify patients
who potentially require a longer treatment course or those whose
outcome will be less satisfactory.