What is Ober’s Test?
Ober’s test is used to evaluate the tightness in the Tensor Fascia Latae muscle (TFL) and Iliotibial band (ITB). Let us now study the clinically relevant anatomy of both the structures, the iliotibial band, and the tensor fascia latae muscle.
Anatomy of Tensor Fascia Latae Muscle And Iliotibial band
The Iliotibial band is a continuation of the tensor fascia latae muscle. It runs along the lateral aspect of the thigh.
- The Tensor Fascia Latae originates from the anterior superior iliac spine’s outer surface, the outer lip of the anterior iliac crest, and the deep surface of the fascia lata.
- The Iliotibial Band (ITB) is a continuation or longitudinal reinforcement of the tensor fascia latae muscle in the thigh.
- The Tensor Fascia Latae inserted or blends into the iliotibial band.
- The Iliotibial Band inserts to Gerdy’s tubercle of the tibia.
- The Tensor Fascia Latae muscle assists in flexion, medial rotation, and abduction of the hip joint.
- The Iliotibial band extends, abducts, and laterally rotates the hip joint.
The connection between TFL and IT Band
The Tensor Fascia Latae runs inferiorly and blends into the Iliotibial band (ITB). A tendon is present in every muscle at both ends which joins them from one bone to another bone. The TFL is just one of the few exceptions, as it blends into the IT band rather than forming its tendon.
The Iliotibial band is a non-contractile portion of tissue. This implies it can not become tight of its own accord. Here, the TFL is inserting or blending into the IT Band. Now when the tensor fascia latae becomes tight, it will pull on the iliotibial band and hence tighten it.
Ober test is used to test the tightness in the IT band and TFL. Frank Ober introduced this test to detect tightness in TFL and IT band’s in an article labeled ‘Back Strain and Sciatica’. In that article, he discussed the connection of tightened TFL and ITB to low backache in May 1935.
Procedure For Performing The Ober Test
- The patient should lie in a side-lying position with the affected side up.
- The patient’s lower leg (bottom hip and knee) should be flexed for stability as well as to flatten the lumbar curve.
- The therapist should stand behind the patient and stabilize the upper iliac crest (pelvis/greater trochanter) with one hand to prevent movement in any direction (to prevent anterior tilting movement of the pelvis).
- With the other hand, the therapist grasp the distal end of the patient’s affected leg and flex the leg to a right angle (90°) at the knee.
How the Test is Performed?
- The therapist then gradually lifts the patient’s upper leg i.e the examiner passively abducts and extends the patient’s hip with the knee flexed to 90°.
- With one hand the upper iliac crest (pelvis/greater trochanter) should be stabilized to prevent the patient’s pelvis anterior tilting.
- While the extension of the hip allows the iliotibial band to pass over the greater trochanter (pelvis) of the femur. This step is very important as this test is performed for detecting iliotibial band tightness.
- After that, the therapist then slowly lower the leg towards the table.
If the TFL and ITB are tight, the leg would remain in an abducted position and does not fall to the table, and the patient would experience lateral knee pain. Therefore, this indicates the positive Ober’s test.
If the TFL and ITB are normal, the leg will slowly drop down towards the table, and the patient won’t experience any pain. Therefore, this indicates the negative Ober test.
In What Case The Ober Test Result Will Be False Negative?
The hip should be slightly abducted and extended during the test, and the hip should not internally rotate and flex during the test. On the whole, if the examiner could not stabilize the hip during the test, the leg would drop down and give a false-negative result.