Definition – What is a Bragard test?
The Bragard test is a clinical sign that is examined within the framework of neurological and orthopaedic examinations. It was named after the German orthopaedist Karl Bragard. It is basically an extension of the Lasègue sign. The Bragard sign is used to detect damage to the spinal nerve roots L4 to S1 or the ischiadic nerve. At the same time, the sign is typically positive for meningitis, so that it can be used to rule out meningitis.
How do you test the Bragard character?
To examine the Bragard’s sign, one first performs the Lasègue test until the pain shoots in. This means that the patient lies on a couch in a supine position. The examiner lifts the affected leg in an extended position.
In doing so, the leg is lifted further stretched, so that a passive flexion of the hip joint occurs. In the case of a positive Lasègue sign, the pain typically kicks in at a flexion of 40 – 60° in the hip joint. After the pain shoots in during the Lasègue test, the leg is lowered until the pain has just disappeared.
This position is held by the examiner and the foot of the affected leg is quickly brought into a dorsal extension. This means that the toes are brought towards the tibia. If this again suddenly causes severe pain in the affected leg, which spreads to the area supplied by the affected nerve root, a positive Bragard sign is present. It indicates a root compression syndrome, irritation of the sciatic nerve or irritation of the meninges. A negative Bragard’s sign does not cause any complaints due to the rapid dorsal extension of the foot.
Causes for a positive Bragard test
The Bragard test is performed with the Lasègue sign to exclude neurological diseases of the spinal nerve roots or meninges. Characteristic causes of a positive Bragard test are inflammation in the area of the spinal nerve roots L4 to S1 and inflammation or irritation of the sciatic nerve.
Causes for a negative Bragard test
The Bragard test is negative if there is no damage to the spinal nerve roots of the spinal nerves L4 to S1, no disturbance of the sciatic nerve and the meninges are healthy. The Bragard’s sign can be negative if the affected person is completely healthy. It can also be negative if there is a herniated disc with damage to higher spinal nerve roots which are not examined by the test.
