Bragard & Modified Bragard Test

Bragard Test is used to evaluate nerve root compression of the lumbar spine, differentiating a genuine Lasegue sign from a pseudo-Lasegue sign.

This test was first described by Karl Bragard who was a German Orthopedist (1890–1973).

See Also:  Lasegue Test

How do you Perform Bragard Test?

• The patient is supine.
• The examiner grasps the patient’s heel with one hand and anterior aspect of the knee with the other hand.
• The examiner slowly raises the patient’s leg, which is extended at the knee (Performing the straight leg raise test).
• At the onset of the Lasegue sign, the examiner lowers the patient’s leg just far enough that the patient no longer feels pain.
• The examiner then passively moves the patient’s foot into extreme dorsiflexion in this position, eliciting the typical pain caused by stretching of the sciatic nerve. 

See Also: Thomas Test

What does a positive Bragard Test mean?

A positive Bragard test is evidence of nerve root compression, which may lie between L4 and S1.

Sensitivity & Specificity

A study to assess the diagnostic accuracy of a Bragard’s test compared with the straight leg raise (SLR) test in patients presenting with electrodiagnostic evidence of L5 and S1 nerve root compression, the Sensitivity & Specificity of this test was:

• Sensitivity: 69.3%
• Specificity: 67.42%.

Notes

• Dull, nonspecific pain in the posterior thigh radiating into the knee is attributable to stretching of the hamstrings and should not be assessed as a Lasegue sign.
• A sensation of tension in the calf may be attributable to thrombosis, thrombophlebitis, or contracture of the gastrocnemius.
• The Bragard sign can be used to test whether the patient is malingering. The sign is usually negative in malingerers.

Modified Bragard test

The Modified Bragard test is performed as following:

The patient is supine on the examination table with both legs straight. The examiner began with the straight leg raise test: If the patient feels no radicular pain or symptoms despite 70° hip flexion (negative SLR test), the foot is then dorsiflexed firmly, if radiating pain below the knee was produced, the Modified Bragard test is positive.

The test is based on the hypothesis that combining hip flexion and knee extension with ankle dorsiflexion will increase the examiner’s capacity to provoke nerve root/sciatic signs and symptoms in SLR-negative patients.

The modified Bragard test is easy to perform and has an acceptable test performance, which can help to increase discriminative power of clinical examination in patients with L5 or S1 nerve root compression who exhibit a negative SLR test result, especially in the acute phase of the disease.

Reference

1. Homayouni K, Jafari SH, Yari H. Sensitivity and Specificity of Modified Bragard Test in Patients With Lumbosacral Radiculopathy Using Electrodiagnosis as a Reference Standard. J Chiropr Med. 2018 Mar;17(1):36-43. doi: 10.1016/j.jcm.2017.10.004. Epub 2018 Jan 12. PMID: 29628807.
2. Marquardt W. Karl Bragard [Karl Bragard]. Z Orthop Ihre Grenzgeb. 1973 Jun;111(3):338-9. German. PMID: 4269946.
3. Homayouni K, Jafari SH, Yari H. Sensitivity and Specificity of Modified Bragard Test in Patients With Lumbosacral Radiculopathy Using Electrodiagnosis as a Reference Standard. J Chiropr Med. 2018 Mar;17(1):36-43. doi: 10.1016/j.jcm.2017.10.004. Epub 2018 Jan 12. PMID: 29628807; PMCID: PMC5883635.
4. Clinical Tests for the Musculoskeletal System 3rd Edition.