Sonographic stratification of adhesive capsulitis using CHL:SGHL ratio-a paradigm shift toward clinico-radiological...

To stratify adhesive capsulitis (AC) into clinically discernible grades using CHL thickness and a novel CHL/SGHL thickness ratio.

This prospective observational study was carried out at a tertiary care university teaching hospital over a period of 18 months. Seventy-five patients enrolled in the study underwent assessment of passive external rotation with a goniometer and graded as, Severe 0-15°, Moderate 15-30°, and Mild 30-45° passive external rotation, followed by ultrasonography of the affected shoulder on S-3000 Acuson (Siemens) by the linear high frequency transducer.

Out of 75 patients, 40 patients had mild to moderate AC and 35 patients had severe AC. The median CHL thickness in the patients who were clinically diagnosed with AC was 2.3 mm, while the CHL thickness ranged from 2.2 to 3.6 mm. We sub-stratified AC into a severe and non-severe subgroup (mild/moderate AC). The median CHL thickness was 2.5 mm in the severe AC subgroup and 2.3 mm in non-severe subgroup. Statistical significance demonstrated between the 2 groups via CHL/SGHL Thickness Ratio (P ≤ .001). Using ROC analysis, CHL thickness ≥2.3 mm predicted severe adhesive capsulitis with 77% sensitivity and 48% specificity, while a CHL/SGHL thickness ratio >1 predicted severe adhesive capsulitis with 89% sensitivity and 98% specificity demonstrating excellent diagnostic performance and statistical significance (P ≤ .001).

Our study successfully demonstrated the ultrasound (US) changes at the rotator interval and their correlation with the clinical severity of adhesive capsulitis (clinico-radiological concordance). CHL/SGHL thickness ratio correlates diagnostically and predicts the severity of AC with higher accuracy than CHL thickness alone. This simple and elegant parameter can aid in clinical management of patients with varying degrees of adhesive capsulitis essentially converting the pandora of conservative and interventional management decisions into a binary scenario for non-severe subgroup and severe subgroup, respectively.

Isolated CHL thickness to quantify adhesive capsulitis into various clinical grades may prove fallacious depending on the clinical stage (pre-freeze/frozen/thaw) of presentation. The novel CHL:SGHL thickness ratio has emerged as a standalone and powerful marker with statistically significant diagnostic accuracy to stratify adhesive capsulitis radiologically into a severe group, requiring interventional management and a non-severe subgroup, often managed conservatively.