Patients with low back pain can be seen everywhere in life, and most of them go to the hospital and have their films taken showing a herniated lumbar disc. In fact, according to the study, only 4% of the population belongs to the real back pain caused by lumbar disc herniation, while 96%, the vast majority of the back pain is other causes. From our soft tissue perspective, the most common occurrence of prolonged low back pain is injury to the lumbar square muscle.
Anatomy of the lumbar square muscle
The lumbar square is an important deep muscle in the lumbar region and is named for its square-like shape. It connects the ribs, lumbar vertebrae and iliac bone. According to its fiber alignment, it can be divided into three bundles.
Iliac rib fibers: attach almost vertically downward to the iliac crest and the iliolumbar ligament and upward to the 12th rib.
Iliolumbar fibers: downward through the ipsilateral iliac attachment point, upward through the upper 4 lumbar transverse processes, and diagonally across and extending medial to the iliac rib fibers.
Lumbar rib fibers: pass downward across the L2-L4 or L5 transverse processes, attach upward to the 12th rib, and cross and extend diagonally to the iliolumbar fibers to form an intertwined structure.
Innervation of the lumbar square muscle: the lumbar plexus divides into the spinal nerves innervated by L1-L4.
Function of the lumbar square muscle.
unilateral contraction of the lumbar square muscle elongates the contralateral lumbar square muscle producing ipsilateral lateral flexion; this muscle also stabilizes the 12th rib during inspiration and passive exhalation, aiding passive exhalation.
simultaneous contraction of the lumbar square muscles bilaterally to extend the trunk.
the lumbar square muscle can work with the contralateral gluteus medius and gluteus minimus to maintain pelvic stability; when the gluteus medius is weak, the contralateral lumbar square muscle will overcontract.
In addition, unilateral shortening of the psoas square can cause problems with the height of the pelvis.
Clinical symptoms of the agonist point of the lumbar square muscle.
In terms of provoked pain points, referred pain in the lumbar square muscle can develop down to the sacroiliac joint and below the hip, sometimes the pain can reach the lower abdomen, groin and greater trochanteric region of the femur towards the anterior iliac crest.
The pain is intense and located deep. Sometimes it can also be stabbing, knife-scraping pain, especially when exercising.
Acute sciatica symptoms: Some spasms occur when acute injury to the lumbar square muscle occurs, raising the height of the pelvis on that side, which can cause seizure of the sciatic nerve that penetrates within the closed foramen, resulting in symptoms of acute sciatica, which is also not necessarily caused by an acute disc herniation.
There are several ranges of involvement pain as follows.
Superior provoked pain points: Involvement of the lateral flank area of the low back, the iliac crest of the buttocks, and the anterior and superior inguinal area. It may also involve the sacroiliac joint, as well as the scrotum and testicles.
Inferior agonist point: the main involvement causes hip pain and pressure pain, and during sleep, the patient is in pain.
Medial provoked pain point: mainly involves the sacroiliac joint and the gluteal sulcus area with severe pain and pressure pain. Sometimes involving to the anterior thigh with stabbing or discharge-like pain.
Signs and symptoms of lumbar square muscle
Active agonizing pain points in the lumbar square muscle may induce the following symptoms.
Intense, deep pain with activity or rest. It is present in almost any position, but is worse when standing or sitting.
Stabbing or knife-like pain when moving the hip or pelvis.
Patients often support their upper body with their hands to keep their balance when sitting or standing. This is a clear sign of active agonistic pain points in the lumbar square muscle.
Coughing and sneezing can worsen the pain.
When patients get up in the morning, they almost crawl to the bathroom on their hands and knees.
Patients are unable to turn their bodies when lying on their backs.
If left untreated, it can further cause groin, genital and sciatica pain.
The lumbar square muscle provoked pain points may further develop into severe hip pain, such as rotor bursitis.
A common posture of the lumbar square agonist point is elevation of the iliac crest on the affected side.
Causes of lumbar square pain points
1. Any activity that involves bending or rotating the lumbar region, such as picking things up from the floor, carrying heavy objects, especially when rotating the lumbar region at the same time. Or when bending over to put on pants and finding a tangle of pant legs, sudden loss of balance. It can strain the lumbar square muscle, or increase the load on the lumbar square muscle. Usually diagnosed as acute lumbar sprain.
2. traffic accidents.
3. hereditary short legs, resulting in lateral pelvic tilt.
4. scoliosis: the patient often tilts to one side and over time, the lumbar square muscle contracts and becomes shorter
5, lumbar lordosis becomes larger, both the psoas major, erector spinae and lumbar square muscles are stretched for a long time.
6, prolonged walking or running on an incline may activate the provocative pain point of the lumbar square muscle or increase its load.
7, lying in a soft bed for a long time, such as sleeping in a hammock or lying on a soft bed. In this way, the lumbar square muscle is in a shortened or stretched position. Over time, it activates its agonizing pain points.
8. walking with a hemiplegic gait: due to stroke, or paralysis of the gluteus medius, etc., which causes walking with each step tilted to the affected side, thus leading to excessive contraction of the lumbar square muscle, which leads to the formation of the agonizing pain point.
Examination of the lumbar square muscle in the following manner.
The patient stands upright with the feet shoulder-width apart and the arms at the sides. The therapist stands behind the patient and places both hands on either side of the patient’s hips to stabilize the pelvis so that it does not rotate and tilt.
At this point, the patient is instructed to slide the hands freely along the outside of the leg without rotating the trunk.
The patient is observed to be able to slide the hands along the lateral side of the leg to the same position, i.e., knee level.
If there is contralateral pain, stiffness or tension during lateral bending this usually indicates injury to the lumbar square.