Hip Pain- Strain of the Rectus Femoris Muscle
One of the causes of hip pain that is often forgotten is the strain of the rectus femoris muscle and tendon. It causes groin pain or anterior hip pain in some athletes. Straining of the rectus femoris muscle is common in athletes who participate in sports such as track, baseball, hockey, and soccer. The injury may occur suddenly when kicking the ball or sprinting from a standing position. It is an overuse problem with repeated tearing, repeated stress, and stretching of the rectus femoris tendon. There will be some scarring, adhesions, or tightness. Strain of the rectus femoris is similar to a tennis elbow-type problem or Achilles tendonitis. It is important to know that there is a lot of causes of hip pain. Within the hip joint, hip pain may be caused by loose bodies, labral tears, avascular necrosis of the femoral head, and arthritis. Hip pain outside of the hip joint may be caused by iliopsoas bursitis. When the physician completes the patient work-up for hip pain, they should be sure to include the rectus femoris strain, which occurs from tearing of the muscle fibers due to stretching of this muscle.
The rectus femoris is an anterior muscle of the quadriceps femoris. The quadriceps femoris is a group of four muscles on the anterior thigh. The rectus femoris has two heads originating from the pelvis. The straight head arises from the anterior inferior iliac spine and the reflected head arises from the groove superior to the acetabulum. The rectus femoris muscle is inserted into the superior border of the patella through the common quadriceps tendon. This muscle flexes the thigh at the hip and it extends the knee. The muscle crosses the hip joint anteriorly, so it flexes the hip joint. Tears or strains of the rectus femoris muscle can be an acute process from forcible eccentric contraction of the muscle. These injuries are usually more distal on the thigh or near the knee. The patient with a strain will have pain in the groin area or anterior part of the hip, but most commonly you will find that the pain is more distal. The chronic overuse injury will give you anterior hip pain, usually near the anterior inferior iliac spine.
In adolescent patients, there may be an avulsion fracture of the anterior inferior iliac spine because it is weak. In adolescents, if you see a piece of bone near the hip joint, this is a sign of pulled rectus femoris muscle. Treatment usually consists of rest and crutches. When inspecting the hip, the physician should go around the hip region and palpate the anterior superior iliac spine. The ASIS is where the Sartorius is attached. Immediately distal is the area of the anterior inferior iliac spine. The physician should palpate this site carefully because this may be the area of the rectus femoris pain. The tensor fasciate latae muscle and the iliotibial band. Try to palpate the rectus femoris muscle through its entire length because you may find pain in the mid-thigh or distally (common). Provocative tests in hip flexion will produce pain. This situation is different from a pulled groin muscle. A pulled groin involves a strain of one of the adductor muscles.
During the Compression Adduction Test, the patient will have pain and decreased strength with resisted leg adduction. During the adductor muscle assessment, while in a sitting position, the examiner has the patient squeeze their thighs with resistance placed at the inside of the knees. After finishing the examination for the rectus femoris muscle strain, and x-ray will probably not be needed. However, in adolescent patients, x-rays may be needed to make sure that there is not an avulsion of the anterior inferior iliac spine. An x-ray will probably will probably be normal so an MRI may be necessary in tough cases that are not getting better with treatment. Treatment consists of ice, rest, NSAIDS, physical therapy, and injections. Surgery is rarely done.