The clinical triad: a structured approach to diagnosing peripheral nerve compressions

Peripheral nerve compression syndromes are a common cause of pain, weakness, and functional limitations, yet they often remain underdiagnosed due to the limitations of traditional diagnostic methods such as electromyography and imaging. This article describes the clinical triad-manual muscle testing (MMT), sensory-collapse testing (SCT), and pain evaluation-as a structured, integrative approach to improving the diagnosis of nerve compressions.

This narrative review examines the anatomical basis and diagnostic application of the clinical triad across common peripheral nerve compression syndromes. The review focuses on the median, ulnar, and radial nerves in the upper extremity, as well as the peroneal nerve in the lower extremity. Each component of the triad is analyzed for its role in detecting nerve compressions, including the reliability of MMT for identifying muscle weakness patterns, the specificity of SCT as a confirmatory tool, and the role of pain assessment in localizing entrapment sites.

The clinical triad provides a structured and accessible diagnostic framework that enhances the detection of nerve compressions, even in early-stage presentations that may evade standard diagnostic tools. It demonstrates adaptability to complex cases, including double- and multiple-crush syndromes, and offers a non-invasive, cost-effective alternative to traditional diagnostic approaches.

The clinical triad enhances diagnostic precision in peripheral nerve compression syndromes by integrating motor, sensory, and pain assessments. Its structured methodology facilitates early detection and targeted interventions, potentially improving patient outcomes while reducing reliance on invasive or resource-intensive diagnostic methods.