The quadratus lumborum is the lateral lumbar stabiliser connecting the iliac crest to the 12th rib and lumbar transverse processes. Trigger points in the QL are one of the most common sources of low back pain, producing deep aching pain that refers to the buttock and lateral thigh. The QL is the primary 'hip hiker' — it fires during gait to prevent pelvis drop on the contralateral side.
| Origin | Posterior iliac crest and iliolumbar ligament |
|---|---|
| Insertion | Inferior border of rib 12 and transverse processes of L1-L4 |
| Nerve Supply | Ventral rami of T12 and L1-L4 |
| Blood Supply | Lumbar arteries |
| Actions | Ipsilateral lateral flexion of the lumbar spine; Elevates the ipsilateral hip when the spine is fixed (hip hiking); Fixes rib 12 for diaphragm function during inspiration; Bilateral contraction: lumbar extension assistance |
|---|
QL trigger points produce unilateral low back pain worsened by rolling over in bed and standing from sitting — they refer to the iliac crest, buttock, greater trochanter, and lateral thigh in a distinctive pattern. Dry needling and manual therapy targeting QL trigger points provide rapid relief. Chronic QL overload from leg length discrepancy requires orthotic correction alongside muscle treatment.
The QL is palpable in the deep lateral flank between the iliac crest and the 12th rib — deep pressure in the prone position with the fingertips hooked under the erector spinae reproduces QL trigger point referral.
QL myofascial pain producing unilateral low back and buttock pain managed with dry needling, manual therapy, and correction of biomechanical contributors.
