Frozen Shoulder as a Metabolic Signal: Advocating Routine HbA1c Screening in Atraumatic Cases

Frozen shoulder, also known as adhesive capsulitis, is often regarded as a localized musculoskeletal disorder. However, it may also be an early indicator of underlying metabolic dysfunction, particularly diabetes or prediabetes. Many patients presenting with atraumatic, progressive shoulder stiffness are found to have elevated HbA1c levels despite normal fasting and postprandial glucose values. Diabetes-related tissue changes, such as collagen glycation and microvascular compromise, may contribute to the development of capsular fibrosis. Recognizing this, routine HbA1c screening in such presentations can aid early diagnosis of dysglycemia and enable timely intervention. This approach may promote interdisciplinary care and improve both systemic and shoulder outcomes. Clinicians should consider frozen shoulder within a broader metabolic-inflammatory framework, especially in middle-aged patients with persistent symptoms and no clear alternative diagnosis.