Execution
- 1Position the patient supine with the hip flexed to 90 degrees.
- 2Stabilize the thigh so the hip remains at 90 degrees of flexion.
- 3Ask the patient to actively extend the knee as far as possible or passively extends the knee depending on the chosen method.
- 4Keep the opposite leg flat and the pelvis controlled.
- 5Measure the remaining knee flexion angle or the knee extension deficit.
Positive outcome
Limited knee extension with the hip at 90 degrees indicates reduced hamstring length. A larger knee extension deficit compared with the opposite side is abnormal. Posterior thigh stretch is expected, but neural symptoms or reproduction of sciatic pain should be interpreted separately.
CommentThe 90-90 SLR is a hamstring length measure, not a diagnostic test for hamstring tendinopathy. It may be affected by neural mechanosensitivity, pelvic position, and patient guarding. Use it as an impairment measure and pair it with pain provocation tests when tendinopathy is suspected.
Low Clinical Value