Hip Flexor Strain

What Is Hip Flexor Strain?

Hip flexor strain can be a bummer. Aside from the pain you can feel from the injury, you may not be able to perform you normal activities for weeks, even months. However, there are ways to deal with hip flexor strain optimally to minimize pain from injury, to obtain proper healing, and to avoid recurrence or chronic hip flexor strain.

A hip flexor strain is an injury caused by a tear or tears in the hip flexor muscle which is typically results to pain in front of the hip or the groins. ^[14]

Hip flexors are the muscles that allow humans to bend their knees and flex the hip. There are several hip flexors in the human body but what is mostly affected in the hip flexor strain are the iliopsoas or the muscles in the inner hip. The iliopsoas muscle originates from the lower back and pelvis and inserts to the femur or the thigh bone. [2, 4, 6]

More specifically, the iliopsoas is the collective term for the two inner hip muscle or dorsal hip muscle flexors: the psoas major and the iliacus muscle. The psoas major originates along the lateral surfaces of spinal column (T12 to L1-L3) and the intervertebral discs between the vertebrates.

This composite muscle is innervated by direct branches of the anterior rami of the lumbar plexus at the levels of L1-L3. On the other hand, the iliacus originates in the iliac fossa of the pelvis.

It is united by the psoas major at the level of the inguinal ligament, crossing the hip joint to insert on the lesser trochanter of the femur. The iliacus is innervated by the femoral nerve which is the group of nerves from the anterior rami of L2-L4. ^{[2, 4]}

When large amount of stress or sudden contraction, more than what hip flexors can handle, is applied, it may cause tearing or stretching of the muscle or tendon. The hip flexor then becomes inflamed and painful; thus, proper treatment is required. ^{[3, 5]}

Causes

• Sprinting or kicking activities- because it involves repeated kicking and prolonged strain to the hip flexors
• Inadequate warm-up
• Weak and inflexible hip flexor muscles
• Trauma or falls
• Cold weather
• Sample group of people at risk: soccer players, cyclists, ,martial artists^{(1, 6, 7)}

 Hip flexor strains are classified into three grades based on the sizes of the site affected and the severity of the tear.

• Grade I Tear- Small number of fibers is slightly strained causing mild pain but still allowing full range of motion (ROM).
• Grade II Tear- Moderate amount of muscle fibers are torn causing moderate loss of ROM
• Grade III Tear- Muscle fibers are completely ruptured with major loss of ROM. This type of tear is uncommon.[1, 6, 8]

Signs & symptoms

Grade I Tear

• Tightness and pain in the front and very top of their thigh but will be able to walk properly
• The injury is usually noticed after cooling down or the following day
• Minimal swelling
• Mild pain when sprinting, kicking a ball, or changing direction quickly

Grade II Tear

• Sharp pull or cramp in the front and very top of the thigh
• Feeling of ‘strained groin’
• Probably be unable to walk properly
• Will not be able to sprint or kick effectively

Grade III Tear

• Severe pain in the front and the very top of the thigh while kicking or sprinting (will almost always stop the player from playing)
• Static contractions of the muscle will be painful and may produce a bulge in the muscle
• Swelling^{(6, 7, 8)}

Diagnosis

• Thorough physical examination and patient’s history are obtained
• May include X-ray, Ultrasound, MRI and/or CT Scans as confirmatory test^{(1, 4)}

Treatment

• Visit a doctor for a more comprehensive assessment, diagnosis, and treatment of the injury especially if Grade III Tear is suspected
• Rest and abstain from physical activities involving the hip while in pain
• Put an ice pack, gel pack, or even cold vegetables wrapped in clean cloth on the painful area every 3 to for hours for 20 minutes. Continue this after three to four days or until pain-free.
• Do ice massage. This is done by freezing water in a Styrofoam cup, then peeling the top of the cup away while retaining some Styrofoam at the bottom to use as a handle. Hold the cup and comfortable pat or place the ice over the painful are for 5 to 10 minutes. Do this several times a day while in pain.
• Take pain reliever such as ibuprofen, acetaminophen, and Non-steroidal Anti-inflammatory Drugs (NSAIDs) prescribed by the doctor.

What do you do during the recovery phase?

• Call a health care provider if pain does not improve after a few weeks with treatment
• Continue to rest hip flexor muscles. Avoid engaging in activities that strains the hip until pain-free. Returning to normal activities too early can turn hip strain into a chronic problem
• When pain and swelling are already absent, apply moist heat for 10 to 15 minutes at a time before doing warm-up and stretching exercises to relax muscles. Moist heat may be heat patches or moist heating pads available in some drug stores. A wet washcloth or towel heated in microwave oven, dryer, or hot water may also be used. Make sure heat is lukewarm and bearable.
• Gradually stretch hip flexor muscles by kneeling on one knee while placing the unaffected leg forward with foot flat on the floor. And while doing this, slowly lean forward at the hips and slightly arch the back. A stretch in front of the hip will be felt. Hold this position for 30 seconds. Do this for three repetitions.
• Stretch the quadriceps of thigh muscles through this stretching exercise. Stand with on a counter or wall for support. Grasp the top portion of the foot and ankle of the injured leg upward so that it approaches the buttocks. While feeling the stretch in front in the thigh, stay on this position for 30 seconds. Repeat one set of three repetitions.
• Any muscle or muscle group that has been injured before is more prone to a repeated injury. Experts advise not to increase exercise intensity, frequency, and duration for more than 10 percent a week or what they call the “ten percent rule”.^{(1, 6, 9, 10)}

How do you avoid Hip Flexor Strains?

• Eat protein-rich foods
• Strengthen hip flexors through hip exercises
• Incorporate stretches in the exercise routine to improve flexibility
• Be sure to do proper warm-up and stretch before physical activities(10, 11)v

References:

1. https://www.physioadvisor.com.au/injuries/hip-groin/hip-flexor-strain/
2. Anderson, Kenneth N.; Mosby’s Medical, Nursing, & Allied Health Dictionary (4th Edition). St. Louis: Mosby-Year Book.1994
3. Platzer, Werner (2004). Color Atlas of Human Anatomy, Vol 1. Thieme Atlas of Anatomy. 2006.
4. http://www.livestrong.com/article /342927-how-to-treat-a-hip-flexor-strain/
5. https://medlineplus.gov/ency/patientinstructions/000682.htm
6. http://www.coreperformance.com/knowledge/injury-pain.hip-injuries.html
7. http://www.muscle-pull.com/grade-2-hip-flexor-muscle-strain/
8. http://www.summitmedicalgroup.com/library/adult_health/sma_iliopsoas_tendonitis/
9. http://www.livestrong.com/article /342927-how-to-treat-a-hip-flexor-strain/
10. http://blog.gameready.com/blog/hip-flexor-pain-causes-treatment-and-prevention