A hip flexor strain is an injury characterized by tearing of one or more of the hip flexor muscles and typically causes pain in the front of the hip or groin.
The group of muscles at the front of the hip are called the hip flexors. The most commonly involved muscle in a hip flexor strain is the iliopsoas. The iliopsoas muscle originates from the lower back and pelvis and inserts into the thigh bone (femur).
The hip flexors are responsible for moving the knee towards the chest during activity and are particularly active when sprinting or kicking. Whenever the hip flexors contract or are put under stretch, tension is placed through the hip flexor muscle fibres. When this tension is excessive due to too much repetition or high force, the hip flexor muscle fibres may tear. When this occurs, the condition is known as a hip flexor strain.
Tears to the hip flexors can range from a small partial tear where there is minimal pain and minimal loss of function, to a complete rupture involving a sudden episode of severe pain and significant disability.
The hip flexor refers to the illiopsoas muscle. The illiopsoas is three different muscles called:
1. Rectus femoris
2. Psoas major
The hip flexor muscles flex and stabilizes the lower extremity. A severe muscle strain usually impairs the hip flexor range-of-motion (ROM). Tight muscles and poor flexibility aggravates tension on tissues. When the lower abdominal muscles and the pelvis are unstable, the hip flexor muscles are overworked thus becoming weak.
Common symptoms of a hip flexor strain is:
- Pain along the front hip downward to the front thigh.
- Pain from Range Of Movement knee towards the chest.
- Running, jumping even walking is painful. Limited ROM and limping can occur.
- Minimal swelling, muscle spasms and bruising.
A hip flexor rehabilitation program helps with balance, mobility, flexibility, and strengthening repair. Consistency with rehab exercises really compliments rehabilitation progress. A hip-flexor muscle injury from running is either grade two or three. A hip flexor muscle strain is graded one to three, partial or severe muscle tear.
Physical Therapy for patients with this condition is vital to hasten the healing process, ensure an optimal outcome and reduce the likelihood of recurrence. Treatment may comprise:
soft tissue massage
joint mobilization (especially the lower back and hip)
the use of crutches
ice or heat treatment
progressive exercises to improve strength and flexibility (particularly of the hip flexors)
activity modification advice
establishment of an appropriate return to activity or sport plan