Thomas Test: How to Check for Hip Flexor Tightness

The Thomas Test is a fundamental orthopedic test used by physiotherapists to assess for tightness or contracture in the hip flexor muscles, specifically the iliopsoas and rectus femoris.

1. Purpose

The primary purpose of the Thomas Test is to **test for** tightness (contracture) in the hip flexor muscles. It can differentiate between tightness in:

• The Iliopsoas muscle (a one-joint hip flexor).
• The Rectus Femoris muscle (a two-joint hip flexor that also extends the knee).

2. How to Perform

1. The patient is positioned in supine (lying on their back) at the very end of the table.
2. The examiner instructs the patient to bring one knee (the non-test leg) up to their chest and hold it firmly. This flattens the lumbar spine (posterior pelvic tilt).
3. The examiner ensures the patient's lower back is flat against the table.
4. The examiner observes the position of the test leg (the one hanging off the table).

3. Positive & Negative Sign

Negative Sign (Test is NEGATIVE)

A negative test (indicating normal length) is:

• The thigh of the test leg remains flat on the table, and the knee remains comfortably flexed at approximately 80-90 degrees.

Positive Sign (Test is POSITIVE)

A positive test (indicating tightness) is one of the following:

• Positive for Iliopsoas Tightness: The thigh of the test leg lifts up off the table.
• Positive for Rectus Femoris Tightness: The thigh of the test leg stays on the table, but the knee extends (straightens).
• Positive for TFL/IT Band Tightness: The thigh of the test leg abducts (moves outward).