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  • Low back pain

  • Lumbar sprain

  • Mechanical low back pain


  • 724.2 Lumbago

  • 847.2 Sprain of lumbar


  • M54.5 Low back pain

  • S33.5 Sprain of ligaments of lumbar spine


  • Pattern 4F: Impaired Joint Mobility, Motor Function, Muscle Performance, Range Of Motion, and Reflex Integrity Associated with Spinal Disorders


A 35-year-old man presents with complaints of unilateral low back pain on his right side. He explains that the pain increases when he inhales deeply, but cannot recall a mechanism of injury. Upon palpation to the lumbar region, the patient complains of tenderness along the 12th rib running inferiorly to the posterior superior iliac crest. The patient has palpable muscle guarding in this region as well. Postural assessment of the patient indicates slight right lateral flexion. The patient tests negative in straight-leg raise test. The patient’s radiograph, which was ordered by the referring physician, is negative for any fractures or foreign bodies.



  • Quadratus lumborum muscle runs from the posterior superior iliac crest to the 12th rib.

  • Can be unilateral or bilateral depending on mechanism of injury.

  • Tenderness along origin, insertion, and line of muscle.

  • Pain over muscle that radiates with trigger point pattern.

  • May cause respiratory issues due to insertion of the muscle on the 12th rib.

  • Most episodes are self-limiting.

Essentials of Diagnosis

  • Diagnosis made by clinical examination.

  • Use of treatment- or impairment-based classification system is useful to determine evidence-based treatment plan.

  • Reproduction of symptoms in specific postures and activities.

  • Rule out systemic disease (red and yellow flags).

FIGURE 138-1

Prone progression. (From Dutton M. Dutton’s Orthopaedic Examination, Evaluation, and Intervention. 3rd ed. Copyright © The McGraw-Hill Companies, Inc. All rights reserved.)

General Considerations

  • Presentation may vary significantly based on anatomical structures and psychosocial factors.

  • Often difficult to determine pathoanatomical cause of pain.

  • Poor spinal alignment, scoliosis, and 12th-rib dysfunction can cause irritation of muscle by altering the length–tension ratio.


  • May be specific to athletes, younger populations prone to extreme spinal movements.



  • Pain lateral to lumbar spine between 12th rib and iliac crest that can be mechanically reproduced

  • Unilateral or bilateral pain along length of muscle or attachment

  • Lumbar segmental and 12th-rib hypomobility

  • Respiratory limitations

  • Difficulty with lumbar spine ROM

  • Often associated with poor body mechanics, core-muscle weakness, and postural deviations

Functional Implications

  • May be a leading cause of ...

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