Sign of the Buttock
‘Sign of the buttock’ term was coined by Cyriax.1 It actually means 7 signs rather than a single one. The sign of the buttock is part of a combination of findings which indicates serious gluteal pathology posterior to the axis of flexion and extension of the hip. It helps to determining whether a patient’s buttocks pain has its origin in the buttock as a local lesion or is referred from the hip, sciatic, nerve or hamstring muscles. It is considered being a red flag and requires returning the patient to the physician for further investigation
Purpose of Testing
To determine the possibility of non-musculoskeletal causes for the patient's symptoms.
The patient suffers from gluteal pain, which may or may not spread down the leg. Colour changes and swelling are not expected at the hip because it is such a deep joint, but they may be associated with trauma, bruising and abrasions. If redness and swelling are present in the buttock area without a history of trauma, the ‘sign of the buttock’ may be suspected.
- Buttock large and swollen and tender to touch
- Straight Leg Raise (SLR) limited and painful
- Limited trunk flexion
- Hip flexion with knee flexion limited and painful
- Empty end feel on hip flexion
- Non capsular pattern of restriction at hip (flex,abd,IR)
- Resisted hip movements painful and weak esp hip extension
This clearly illustrates the importance of performing the passive hip tests immediately after having tested the straight leg raise in the lumbar examination. Some resisted hip tests may prove positive.
A straight leg raise is performed passively by the examiner (the patient cannot usually perform an active SLR). If the SLR is positive, the end-feel is usually spasm or capsular, but definitely painful. Return the patient to neutral. Passively flex the patient's hip, but this time with the ipsilateral knee flexed to end-range. Assess if further hip flexion can be achieved.
If no change in range of motion, the pathology is within the hip or buttock, and not the hamstrings or sciatic nerve. The second part of the test usually has an empty end-feel and is more painful than the first part. To be positive, the Sign of the Buttock must have all present: restriction of SLR concurrently with limited hip flexion and a non-capsular pattern of restriction of hip joint ROM.
Importance / Explanation
When performing a SLR, a pathology in the hamstrings, sciatic nerve, buttock, or hip may cause limitations. If the knee is flexed, the stress is taken off the hamstrings and sciatic nerve (because they cross the knee), so remaining limitation is due to pathology of the hip or buttock. With an empty end feel, we know that there is a potentially serious pathology involved.
• Rheumatic bursitis
• Osteomyelitis of the upper femur
• Neoplasm of the upper femur
• Neoplasm of the ilium
• Fractured sacrum
• Ischiorectal abcess
• Septic sacroilitis
• Septic gluteal bursitis 
- Kesson M, Atkins E. Orthopaedic Medicine: A Practical Approach. 2nd ed. Elsevier ; 2005
- Palmer M, Epler M. Fundamentals of Musculoskeletal Assessment Techniques. 2nd ed. Lippincott Williams & Wilkins; 1998