Bonnet Sign (Piriformis Sign) – For Detecting Sciatica

What is Bonnet Sign?

The bonnet sign is used to provoke the symptoms of sciatica. The Bonnet sign is also known as the piriformis sign.

The procedure of performing the Bonnet Sign

  • The patient is asked to lie down in a supine lying position.
  • After that, the patient is asked to flex his leg at the hip and knee joint.
  • Now, after that, the examiner adducts and internally rotates the patient’s leg, as shown in the diagram below.


Here is the diagram of Hip Internal and External rotation

hip internal rotation and external rotation

Test Results of the Bonnet Sign

Adducting and internally rotating the leg with the hip and knee flexed provokes the symptoms of sciatica. As adduction and internal rotation of the leg stretch the sciatic nerve as it passes through the piriformis muscle.

When the examiner performs the procedure (adducts and internally rotates the patient’s leg), this stretches the sciatic nerve, so if the patient is suffering from sciatica, the patient will experience an increment in pain.

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Nerve Root Disorder Test

Duchenne Sign – Used to assess a nerve root disorder.

Thomsen Sign – Indicates or signals sciatic nerve root irritation.

Tiptoe and Heel Walking Test – Identifies or pinpoints a nerve root disorder in the lumbar spine.

Sacroiliac Joint Tests

Mennell’s Sign / Mennell’s Test – Used to assess degenerative processes in the sacroiliac joint.

Springing Test – To detect functional impairment in the Thoracic & Lumbar spine & Sacroiliac Joint.

Gaenslen’s Test – To detect any pathology or dysfunction around the sacroiliac joint.

Standing Flexion Test/ Standing Forward Flexion Test – To assess sacroiliac joint dysfunction.

Faber Test / Patrick’s Test – Used to assess the pathology or dysfunction at the hip joint, muscles around the hip joint, and at the sacroiliac joint.

Thoracic Spine Test 

Ott Sign – For Measuring the ROM of the Thoracic Spine

Cervical Tests 

Cervical Flexion Compression Test –  To identify if there is a Herniated disk in the Cervical spine.

Jackson Compression Test –  To Detect Cervical Radiculopathy (Cervical Nerve Root Compression).

Spurling Test – For Diagnosing Cervical Radiculopathy.

Cervical Distraction Test – To detect the presence of cervical radiculopathy.

O’Donoghue Test – Helps in differentiating between muscular pain (strain) and ligamentous pain (articular problem) in the cervical spine.

Soto Hall Test – For Detecting Problem in Patient’s Neck (Cervical Spine).

Maximum Compression of the Intervertebral Foramina Test of Cervical Spine – For Detecting Facet Joint Dysfunction in the Cervical Spine.

Some other Tests

Transverse Humeral Ligament Test – Indicates transverse humeral ligamentous insufficiency, and it also indicates biceps tendinitis.

Lippman Test – To detect pathology in the long head of the biceps tendon.

Pelvic Ligament Tests – used for the assessment of the pelvic ligaments.

Supported Forward Bend Test (Belt Test) – helps in differentiating lumbar pain and sacroiliac pain.

Adam’s Forward Bend Test – For detecting the presence of scoliosis (either functional or structural).

Noble Compression Test/Noble Test –  To assess pain coming from iliotibial band syndrome.

Neer Test –  For detecting the presence of shoulder impingement syndrome.


Clinical Tests for the Musculoskeletal System: Examinations-Signs-Phenomena by K. Buckup

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