A diagnostic tool for people with lumbar instability: a criterion-related validity study

Area of Science:

• Orthopedics
• Physical Therapy
• Diagnostic Accuracy

Background:

• Lumbar instability diagnosis relies on clinical tests with conflicting accuracy.
• Improved diagnostic methods are needed for effective clinical application.
• X-ray imaging serves as the reference standard for lumbar instability.

Purpose of the Study:

• To determine the diagnostic probability of clinical tests for lumbar instability.
• To identify which clinical tests are most effective when used together.

Main Methods:

• A cross-sectional diagnostic validity study.
• 140 participants with chronic low back pain were assessed.
• Multivariate regression analyzed 14 clinical examinations against X-ray findings.

Main Results:

• 12.85% of participants showed radiological lumbar instability.
• A combination of three tests (interspinous gap change, passive accessory intervertebral movement, posterior shear) achieved 67% diagnostic ability.
• This combination yielded sensitivity of 5.56, specificity of 99.18%, +LR of 6.78, and -LR of 0.95.

Conclusions:

• Three specific clinical tests can effectively identify lumbar instability.
• These tests are simple, reliable, and safe for clinical use by physical therapists.
• Recommended for suspected cases in the absence of X-ray assessment for timely intervention.