What is Freiberg's test?

Freiberg’s Test: A Clinical Tool for Sciatic Nerve Assessment

Introduction

Freiberg’s Test is an orthopedic clinical examination technique used to detect sciatic nerve irritation, particularly due to piriformis syndrome. This test assesses the involvement of the sciatic nerve by reproducing symptoms through forced internal rotation of the extended hip. Freiberg’s Test is especially valuable when differentiating between true sciatica and piriformis-related sciatic symptoms, helping clinicians determine the origin of a patient's lower limb radiating pain.

Purpose and Clinical Use

The main objective of Freiberg’s Test is to evaluate sciatic nerve entrapment or irritation as it passes beneath or through the piriformis muscle. Since piriformis syndrome can mimic lumbar radiculopathy, this test becomes particularly relevant in outpatient physiotherapy or orthopedic evaluations, where distinguishing between spinal and peripheral nerve involvement is essential for correct diagnosis and treatment.

Test Procedure

To perform Freiberg’s Test, the patient lies supine (on their back) with their legs extended. The examiner then passively moves the affected leg into hip flexion followed by internal rotation of the extended hip. During this motion, the piriformis muscle is stretched and compressed against the sciatic nerve. A positive Freiberg’s Test is indicated by the reproduction of pain or discomfort in the buttock or along the path of the sciatic nerve into the posterior thigh or leg.

Interpretation of Results

A positive result suggests sciatic nerve irritation likely caused by piriformis syndrome or other external compression sources in the gluteal region. The test is particularly helpful when used in combination with other assessments like the FAIR test (Flexion, Adduction, and Internal Rotation), Pace’s Sign, or palpation of the piriformis muscle. It is not a standalone diagnostic tool but contributes to a broader understanding of the patient's neurological and musculoskeletal status.

Anatomical Considerations

The piriformis muscle originates from the anterior surface of the sacrum and inserts onto the greater trochanter of the femur. The sciatic nerve typically passes beneath the piriformis, though anatomical variations exist. Compression of the sciatic nerve due to hypertrophy, spasm, or inflammation of the piriformis can result in pain and symptoms that mimic lumbar radiculopathy. Freiberg’s Test provokes these symptoms by rotating the femur and stretching the piriformis, thereby irritating the sciatic nerve if compromised.

Clinical Significance

Freiberg’s Test is particularly significant for identifying non-discogenic causes of sciatica. This has implications for treatment, as piriformis syndrome may respond well to physiotherapy, stretching, muscle release techniques, and postural correction rather than spinal surgery or decompression. Identifying piriformis involvement early in the clinical examination can prevent unnecessary imaging and invasive procedures.

Precautions and Limitations

The test should be performed carefully, especially in patients with acute hip joint inflammation, recent hip surgery, or severe lower back pain. Also, because other conditions (e.g., hip osteoarthritis or lumbar disc herniation) can cause overlapping symptoms, this test should never be used in isolation. Clinical correlation with a full neurological exam, lumbar spine tests, and possibly imaging is often required for an accurate diagnosis.

Conclusion

Freiberg’s Test is a useful and simple clinical maneuver to identify sciatic nerve irritation stemming from the piriformis muscle. When used in combination with other orthopedic and neurological assessments, it aids in diagnosing piriformis syndrome and guides effective, targeted treatment. Its non-invasive nature and ease of application make it a routine part of many musculoskeletal assessments involving posterior hip and leg pain.

References

1. Freiberg's Test - Physiopedia. Available at: https://www.physio-pedia.com/Freiberg%27s_Test

2. Hopayian K, Song F, Riera R, Sambandan S. The clinical features of the piriformis syndrome: a systematic review. Eur Spine J. 2010;19(12):2095–2109.

3. Boyajian-O’Neill LA, McClain RL, Coleman MK, Thomas PP. Diagnosis and management of piriformis syndrome: an osteopathic approach. J Am Osteopath Assoc. 2008;108(11):657–664.

4. Durrani Z, Winnie AP. Piriformis muscle syndrome: an underdiagnosed cause of sciatica. J Pain Symptom Manage. 1991;6(6):374–379.