3rd Lumbar Nerve Syndrome

One of the most common causes of Low Back Pain in patients with the Rothbarts Foot or the PreClinical Clubfoot Deformity

Subjective Findings:

  • Pain, itching, tingling and numbness on the outside part of the mid to lower thigh (typically not centered but more prominent on either the right or left side of the low back

Objective Finding:

  • Symptoms are reproduced with direct pressure with a finger over the inguinal ligament
  • Muscle belly of the Quadratus Lumborum Muscle is tight and painful

Common Etiology of The 3rd Lumbar Nerve Syndrome:

  • An anterior rotation of the innominate (hip) bone which places the Quadratus Lumborum muscle on a stretch. This stretching of the muscle can compress the branches of the femoral nerve (3rd lumbar nerve) against the spinal column.

3rd Lumbar Nerve Syndrome (frequently occurs in Rothbarts Foot). The white arrow points to area where the lumbar (femoral) nerve can be compressed by a tight Quadratus Lumborum muscle.

Oblique view of the Pelvis and Lumbar Spine 

  • Anterior/External rotation of the left innominate (hip) bone places the right Quadratus Lumborum muscle on a stretch.  
  • This can compress the lumbar nerve resulting in a peripheral neuropathy

Differential Diagnosis:

  • Unaccustomed running
  • Tibial or fibular fractures
  • Direct blow to the leg
  • Can easily be misdiagnosed as an inflammation of the sacral iliac articulation