Describe the Kemp test and what it assesses.

• A. Flexion and rotation of the trunk with axial loading to reproduce foraminal impingement or nerve root irritation, indicating lumbar radiculopathy.
• B. Extension and rotation of the trunk with axial loading to reproduce foraminal impingement or nerve root irritation, indicating lumbar radiculopathy.
• C. Lateral bending of the trunk with pressure on the sacrum to assess sacroiliac dysfunction.
• D. Passive straight leg raise to differentiate hamstring tightness from radiculopathy.

Answer: (B)

Kemp test works by loading the lumbar spine in a way that narrows the neural foramina and compresses the nerve roots. Extending the trunk tightens posterior structures and reduces the space where the exiting nerves pass; adding rotation (usually toward the side being tested) further closes the foramen, and a downward axial load increases the pressure on those neural elements. If this maneuver reproduces radicular pain or leg symptoms, it points to foraminal impingement or nerve root irritation consistent with lumbar radiculopathy, such as from disc herniation or stenosis. The other maneuvers target different issues—flexion generally does not reproduce foraminal compression, sacroiliac loading assesses SI dysfunction, and the straight-leg raise differentiates hamstring tightness from nerve tension rather than testing foraminal encroachment.