How to measure hip range of motion

Clinical guide · Updated July 2026

To measure hip flexion with a goniometer, position the patient supine, center the fulcrum over the greater trochanter, align the stationary arm with the lateral midline of the trunk and the moving arm with the lateral midline of the femur toward the lateral epicondyle, then bring the thigh toward the chest and read the angle. Normal hip ROM is about 120° flexion, 45° abduction, and 45° external rotation (AAOS). The steps, landmarks, and reliability evidence are below.

120°Normal hip flexion (AAOS)
Good ICCIntra-rater test-retest reliability of manual hip goniometry (Nussbaumer et al., 2010)
Hip flexion measurement: patient supine, iPhone along the thigh, showing the 0 to 120 degree arc as the thigh lifts toward the chest.
Hip flexion placement from the Goniometer app — patient supine, phone along the femur, reading 0°–120°.

Normal hip range of motion

Normal hip range of motion (AAOS)
MovementNormal ROM
Flexion120°
Extension30°
Abduction45°
Adduction30°
External rotation45°
Internal rotation45°

See the full normal range of motion chart for every joint. The Goniometer app guides hip flexion and external rotation with animated placement.

What you need

How to measure hip flexion, step by step

  1. Position the patient. Supine with the legs extended and relaxed — this is the 0° starting position.
  2. Find the landmarks. Locate the greater trochanter, the lateral midline of the femur toward the lateral epicondyle, and the lateral midline of the trunk.
  3. Center the fulcrum. Place the goniometer axis over the greater trochanter.
  4. Align the arms. Line the stationary arm along the lateral trunk and the moving arm along the lateral midline of the femur.
  5. Move to end range. Bring the thigh toward the chest until it stops, allowing the knee to bend, and keep the arms tracking the landmarks.
  6. Read and record. Read the angle at end range and note the side (L/R) and patient position.

Hip external rotation

Hip external rotation measurement: hip and knee flexed to 90 degrees, shin swinging inward so the foot moves toward the midline, 0 to 45 degrees.
Hip external rotation — hip & knee at 90°, foot swings to the midline, 0°–45°.

Flex the hip and knee to 90° and swing the shin inward so the foot moves away from the midline; normal is about 45°. In the app this uses the phone’s attitude reference with the shin as the pointer. Hip abduction (about 45°) and internal rotation (about 45°) are measured similarly.

Getting a reliable measurement

Manual hip goniometry is most reliable when the same examiner measures the same way each time. Nussbaumer and colleagues found manual goniometers valid and reliable for passive hip range of motion on a test-retest (intra-rater) basis when compared against an electromagnetic tracking system. Four habits keep readings repeatable:

Measuring hip ROM with an iPhone

A smartphone goniometer app replaces the two-armed goniometer with the phone’s gravity-referenced motion sensor: lay the phone along the thigh, set zero, and the change in tilt as the hip flexes is the joint angle. Peer-reviewed research finds smartphone measurement valid and reliable for hip ROM, comparable to a universal goniometer — see the accuracy evidence. A 2022 study reported high intra-rater reliability (ICC above 0.72) for smartphone hip goniometry, again strongest with a single examiner (Takeda & Furukawa).

Measure the hip on your iPhone. Goniometer shows animated placement for hip flexion and external rotation, with the AAOS normal range beside every reading — free to measure. Download Goniometer on the App Store.

Frequently asked questions

What is normal hip range of motion?

About 120° flexion, 30° extension, 45° abduction, 30° adduction, and 45° of internal and external rotation, per AAOS.

How do you measure hip flexion with a goniometer?

With the patient supine, center the fulcrum over the greater trochanter, align the stationary arm with the lateral trunk and the moving arm with the lateral femur, bring the thigh toward the chest, and read the angle.

What landmarks are used to measure the hip?

The greater trochanter (axis), the lateral midline of the femur toward the lateral epicondyle (moving arm), and the lateral midline of the trunk (stationary arm).

How reliable is hip goniometry?

Reliable with one examiner: Nussbaumer et al. found manual goniometers valid and reliable for passive hip ROM on a test-retest basis. Consistent technique and pelvic stabilization matter most.

Can you measure hip range of motion with a phone?

Yes — a smartphone goniometer app reads the phone’s motion sensor and has shown validity and reliability comparable to a universal goniometer in peer-reviewed research.

References

Related guides

Goniometer is an educational and reference tool. It is not a medical device and is not intended for diagnosis or treatment decisions.