How to measure shoulder range of motion

Clinical guide · Updated July 2026

To measure shoulder flexion with a goniometer, position the patient supine with the arm at the side, center the fulcrum over the lateral aspect of the acromion, align the stationary arm with the midaxillary line of the trunk and the moving arm with the lateral midline of the humerus, then raise the arm overhead and read the angle. Normal shoulder ROM is about 180° flexion, 180° abduction, and 90° external rotation (AAOS). The steps, landmarks, and reliability evidence are below.

180°Normal shoulder flexion and abduction (AAOS)
ICC to .99Intratester reliability of shoulder goniometry (Riddle et al., 1987)
Shoulder flexion measurement: patient supine, iPhone along the upper arm, showing the 0 to 180 degree arc as the arm raises overhead.
Shoulder flexion placement from the Goniometer app — patient supine, phone along the humerus, reading 0°–180°.

Normal shoulder range of motion

Normal shoulder range of motion (AAOS)
MovementNormal ROM
Flexion180°
Extension60°
Abduction180°
Adduction40°
External (lateral) rotation90°
Internal (medial) rotation70°

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

What you need

How to measure shoulder flexion, step by step

  1. Position the patient. Supine with the arm at the side and the palm facing the body — this is the 0° starting position.
  2. Find the landmarks. Locate the acromion process, the lateral midline of the humerus toward the lateral epicondyle, and the midaxillary line of the trunk.
  3. Center the fulcrum. Place the goniometer axis over the lateral aspect of the acromion.
  4. Align the arms. Line the stationary arm along the midaxillary line of the trunk and the moving arm along the lateral midline of the humerus.
  5. Move to end range. Raise the arm forward and overhead until it stops, keeping the arms tracking the same landmarks.
  6. Read and record. Read the angle at end range and note the side (L/R) and patient position.

Shoulder abduction

Shoulder abduction measurement: patient supine viewed from above, arm moving out to the side and overhead, 0 to 180 degrees.
Shoulder abduction — arm out to the side and overhead, 0°–180°.

Keep the patient supine and move the arm out to the side and overhead in the frontal plane, with the fulcrum near the anterior acromion. Normal abduction is about 180°.

Shoulder external rotation

Shoulder external rotation measurement: shoulder abducted to 90 degrees, elbow bent, forearm rotating back toward the head, 0 to 90 degrees.
Shoulder external rotation — shoulder abducted 90°, forearm rotates toward the head, 0°–90°.

Abduct the shoulder to 90° with the elbow bent to 90°, then rotate the forearm back toward the head. Normal is about 90°. In the Goniometer app this uses the phone’s attitude reference so it reads true rotation in any orientation.

Getting a reliable measurement

Shoulder goniometry is most reliable when the same examiner measures the same way each time. Riddle and colleagues, measuring passive shoulder motion in a clinical setting, found intratester (same-examiner) reliability up to ICC .99, but markedly lower intertester (different-examiner) reliability for rotation and horizontal movements. Four habits keep readings repeatable:

Measuring shoulder ROM with an iPhone

A smartphone goniometer app replaces the two-armed goniometer with the phone’s gravity- and attitude-referenced motion sensor: lay the phone along the arm, set zero, and the change in orientation as the shoulder moves is the joint angle. Peer-reviewed research finds smartphone measurement valid and reliable for shoulder ROM, comparable to a universal goniometer — see the accuracy evidence. A 2023 study found a smartphone application produced shoulder ROM measurements comparable to a physical therapist’s goniometer (Soeters et al.).

Measure the shoulder on your iPhone. Goniometer shows animated placement for shoulder flexion, abduction, 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 shoulder range of motion?

About 180° flexion, 60° extension, 180° abduction, 90° external (lateral) rotation, and 70° internal (medial) rotation, per AAOS.

How do you measure shoulder flexion with a goniometer?

With the patient supine, center the fulcrum over the lateral acromion, align the stationary arm with the midaxillary line of the trunk and the moving arm with the lateral midline of the humerus, raise the arm overhead, and read the angle.

What landmarks are used to measure the shoulder?

The acromion process (axis), the lateral midline of the humerus toward the lateral epicondyle (moving arm), and the midaxillary line of the trunk (stationary arm).

How reliable is shoulder goniometry?

Reliable with one examiner: Riddle et al. reported intratester ICC up to .99, though intertester reliability was lower for rotation and horizontal movements. Consistent technique matters most.

Can you measure shoulder 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.