Improving Outcomes for Back Pain and LE Radiculopathy
Differential Diagnosis of Pathology Involving the Sacroiliac Region
Overview: Back Pain and Sciatica cases are prevalent within the US population and a frequent cause of visits to healthcare offices.
Producing consistent and positive outcomes relies first on a correct diagnosis being established for the cause of the back pain and/or sciatica.
The most common causes of musculoskeletal back pain are: herniated disc, stenosis, arthritis, DDD (Degenerative Disc Disease), muscle spasm, facet arthopathy, spondylosis, sponylolisthesis, compression fracture and pathologies of the sacroiliac region.
One of the more difficult regions to properly diagnose is the sacroiliac joint and pelvis.
Recent research has utilized a combination of 4 or 5 pain provocation tests to identify sacroiliac lesions.
A study published in the Archives of Physical Medicine and Rehabilitation utilized these 5 pain provocation tests to diagnose sacroiliac involvement (using 50% pain relief with injection of local anesthetics into the sacroiliac joint as the Reference Standard):
Distraction
Thigh Thrust
Gaenslen’s Test
Patrick sign
Compression
If at least 3 of the 5 tests were positive, SI joint involvement was indicated.
Here we will describe the Distraction test and indication of positive findings.
The Distraction test is performed with the patient supine. The examiner applies a cross-arm pressure to both anterior superior iliac spines. The test is positive if familiar symptoms are increased or produced.
A study published in Clinical Rheumatology performed the test on 40 patients with chronic low back pain and using MRI diagnosis of sacroiliitis as the Reference Standard, found the following: Sensitivity (True-positive rate) 0.23 Specificity (True-negative rate) 0.81
Discussion of the Distraction Test and Clinical Application
When combined with a series of pain provocation tests, the Distraction test is an important part of the differential diagnosis of SI Joint lesions.