Association between subscapularis trigger point and frozen shoulder: A cross sectional study.

Background: Frozen shoulder (FS) is one of the most common shoulder conditions characterized by pain, restricted range of motion and high morbidity. Though FS is known as adhesive capsulitis, presence of capsular adhesions has been rebutted and the nomenclature adhesive capsulitis is debated. It has been proposed that FS is a condition of cytokine driven capsular, ligamentous fibrosis and contracture. Despite extensive research on it, still it is unclear that how far the capsular contracture contribute to range of motion restriction in FS. Evidence also suggested that myofascial trigger points play a role in restricted range of motion.

Objective: To find an association between subscapularis trigger point and frozen shoulder.

Study Design: Cross-sectional study.

Method: 143 Patients were screened for inclusion and exclusion criteria, out of which 100 patients, were selected for the study. Manual palpation was performed to look for subscapularis muscle trigger points via axillary approach on both the affected and unaffected side. Trigger point diagnosing criteria was used to diagnose subscapularis trigger points.

Results: Results have shown that there was an association between subscapularis trigger point and frozen shoulder (X 2 = 32.151 P < 0.0001) on the affected side. We used Phi coefficient to measure the degree of association which denotes (Phi = 0.567 P < 0.0001) strong association between frozen shoulder and subscapularis trigger point on the affected side compared to unaffected side (X 2 9.157; P < 0.002: Phi:0.303: P < 0.002).

Conclusion: This study concluded that there appears to be a strong association between subscapularis trigger point and frozen shoulder.