The hip, which links the trunk and lower extremities together, the iliopsoas is the main flexor between the trunk and lower extremities. The “iliopsoas” is composed of two muscles, the psoas major (psoas major m.) and the iliacus (iliacus m.) (a small number of people have psoas minor muscles, so some people have three), and the psoas major is one muscle. Originates from the transverse process of the twelfth thoracic vertebra to the fifth transverse process of the lumbar vertebra, passes down through the pelvis, and descends with the iliacus muscle originating from the medial iliac fossa, through the pelvis rim and the anterior border of the hip joint capsule, through the iliac The anterior inferior ridge and the iliopectineal eminence are connected to the lesser trochanter of the femur. There is a bursa between the pelvic rim and the iliopsoas tendon, called the iliopsoas bursa, that provides cushioning between the iliopsoas and the pelvic rim.
The main function of the iliopsoas muscle is to flex the hip (hip flexion) and rotate the thigh slightly (femur external rotation) when the muscle contracts, so The iliopsoas is used in movements such as running and jumping, squatting and sitting, and forward kicking. In addition, the lower limbs do not move, and when the iliopsoas muscle contracts, the pelvis can be tilted forward and the lumbar lordosis can be maintained to maintain the body’s upright and lumbar-straight posture.
iliopsoas syndrome
iliopsoas syndrome, in short, is a general term for the inflammation and pain of the iliopsoas tendon itself or the soft tissue around the tendon, which may include a diagnosis of iliopsoas muscle Myokeyitis, iliopsoas fasciitis, iliopsoas bursitis, snapping hip…etc. The most common causes are (1) acute injury and (2) overuse due to repeated hip flexion. It can happen at any age, a little more in young people and a little more in women.
Athletes who require more repeated hip flexion or prolonged hip flexion (iliopsoas shortening) are prone to this, such as cyclists (below), rowers , football players, ballet dancers, taekwondo players, judo players, runners (especially those who often run uphill sections)…etc.
Also sit in a curled baby position (such as a fishing rod position) for long periods of time, lean forward too much when sitting at a desk, or put the soles of the feet on the legs of the chair When you go up or sit on the sofa, lift your feet and put your feet on the bench, which will make the knee joint higher than the hip joint, so that the iliopsoas muscle is in a state of contraction for a long time, which is also prone to symptoms. In addition, hospitalized patients are also prone to symptoms if they sit on the bed for too long, or sit on the bed and play with their mobile phones (as shown on the left in the picture below).
Symptoms of iliopsoas syndrome
Patients usually There will be pain in the front of the hip joint or in the groin, from dull pain at the beginning to obvious pain later, pain at the beginning of activity but no pain at rest, and pain after movement or rest. Pain usually occurs between sports or after certain sports, such as running, hiking, kicking a ball, sit-ups, or climbing stairs.
Some pains can be induced when standing up after sitting for a short period of hip flexion. Some people experience pain when going up and down stairs. When the pain is severe or the inflammation is severe, you may need crutches to complete the movement of walking.
Groin pain can sometimes radiate to the inside of the knee, especially when standing up; some people feel tightness in the groin or front of the hip combined with pain on the inside of the knee. To be more serious, when standing upright, in addition to the groin and the inside of the knee, the waist on the same side will also feel sore and soft, and a few people will also have a feeling of dull pain in the abdomen.
Some patients may hear an internal snapping hip on the front of the hip joint when they change from sitting to standing. Because the iliopsoas muscle is tight, during the flexion and extension of the hip joint, it will rub against the pelvic edge to produce sound and pain, which is often associated with iliopsoas bursitis. This situation is more common in young adolescent patients who are in the rapid growth period. In addition to the above pain, some patients also experience pain at the patellar ligament and the front of the knee, because running with tight iliopsoas increases quadriceps tension and patella-femoral pressure.