For the Thomas test, which position is used for evaluating hip flexors?

• A. Supine with lumbar spine stabilized and involved leg extended; contralateral hip flexed to the abdomen.
• B. Prone with knee bent.
• C. Seated with leg extended.
• D. Standing with leg abducted.

Answer: (A)

The Thomas test evaluates hip flexor length by isolating hip motion in a supine position while preventing movement from the spine. To do this reliably, you bring one thigh to the chest to flatten the lumbar spine, then observe the position of the other leg as you let it lie extended on the table. Stabilizing the lumbar region ensures any observed limitation is from the hip flexors and not from spinal movement. In this setup, the leg being tested stays extended on the table while the opposite hip is flexed toward the abdomen. If the hip flexors are tight, the tested leg cannot drop fully into extension and the pelvis may tilt or the opposite knee remains flexed toward the chest, indicating a positive result. This configuration is why that position is used for evaluating hip flexors.