Rotator cuff (RC) tears, both partial and full-thickness lesions, are a common source of pain and disability in the adult’s shoulder. Methods: In this study a retrospective cross-sectional study was conducted in 129 patients with shoulder pain, stiffness, restricted motion and trauma. Their age were between 20–65 years those attended into the clinical centers in Sudan (2021–2024). High-resolution ultrasonography (HR-US) was used in a uniform tendon-specific protocol in order to increase the diagnostic precision, reproducibility, then to study the Specificity and Sensitivity of HR-US clinical orientation on a partial and full- thickness tear on Rotator Cuff muscles. The examinations were performed with a 7.5-/12-MHzlinear-array transducer following ESSR guidelines. SPSS v23 was used for statistical analysis and level of significant at p < 0.05. Results: HR-US was over 90% sensitive and over 94% specific in identifying full-thickness tears and had excellent agreement with MRI. Supraspinatus and infraspinatus tendons had optimal diagnostic accuracy, with HR-US superior to MRI in the identification of some partial subscapularis tears. Standardized protocols improved inter-operator variability elimination and diagnostic consistency. Conclusion: HR-US is a highly precise, cost-effective, and interactive first-line imaging modality for evaluating rotator cuff disease. Its real-time imaging can provide functional information beyond MRI, leading to early and precise diagnosis. If performed under formalized protocol, HR-US reduces operator reliance and enables wide acceptance, particularly in resource-poor health care settings.