Sports Medicine
Sports Injury Prevention & Rehabilitation

+1-650-815-6552 / +33784264352

Voted Best Sports Therapy Clinic in the San Francisco Bay Area 2010-2018!

Hip Flexor Strain

(Also known as Hip Flexor Injury, Iliopsoas Strain, Psoas Strain, Hip Flexor Tear, Strained Iliopsoas Muscle, Torn Iliopsoas Muscle, Pulled Hip Flexor)
What is a hip flexor strain?

A strain is a stretch or tear of a muscle or tendon, a band of tissue that connects muscle to bone. The tendon may be inflamed. Inflammation of a tendon is called tendonitis. The hip flexor muscles allow you to lift your knee and bend at the waist. The hip flexors are made up of three different muscles. The Rectus Femoris, Psoas Major, and Illiacus. These muscles work together to help flex the hip, and to provide stability for the lower extremity. The Rectus Femoris is one of the quadriceps muscles, and also helps with knee extension. These muscles can be strained during activities, and can cause pain and loss of motion at the hip.

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 (i.e. bending the hip) 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.

Hip flexor strains range from grade 1 to grade 3 and are classified as follows:
Grade 1 Tear: a small number of fibres are torn resulting in some pain, but allowing full function.
Grade 2 Tear: a significant number of fibres are torn with moderate loss of function.
Grade 3 Tear: all muscle fibres are ruptured resulting in major loss of function.

The majority of hip flexor strains are grade 2.

Causes of a hip flexor strain
Hip flexor strains most commonly occur due to a sudden contraction of the hip flexor muscles (particularly in a position of stretch). They often occur during sprinting or kicking activities. This is particularly so during explosive acceleration or when a footballer performs a long kick, particularly following an inadequate warm-up.
Occasionally, patients may develop this condition gradually due to repetitive or prolonged strain on the hip flexor muscles. This may occur due to repetitive kicking or sprinting excessively. Hip flexor strains are commonly seen in running and kicking sports such as football and soccer.

Signs and symptoms of a hip flexor strain
Patients with this condition usually feel a sudden sharp pain or pulling sensation in the front of the hip or groin at the time of injury. In minor strains, pain may be minimal allowing continued activity. In more severe cases, patients may experience severe pain, muscle spasm, weakness and an inability to continue the activity. Patients with a severe hip flexor strain may also be unable to walk without limping.
Patients with this condition usually experience pain when lifting the knee towards the chest (especially against resistance) or during activities such as running, kicking or going upstairs. It is also common for patients to experience pain or stiffness after these activities with rest, especially upon waking in the morning. Swelling, tenderness and bruising may also be present in the hip flexor muscles. In cases of a grade 3 tear a visible deformity in the muscle may be evident.

Diagnosis of a hip flexor strain
A thorough subjective and objective examination from a physiotherapist is usually sufficient to diagnose a hip flexor strain. Further investigations such as an X-ray, Ultrasound, MRI or CT scan may be required to confirm diagnosis and exclude other pathology. In severe cases, particularly adolescents, an x-ray may be advisable to exclude the possibility of an avulsion fracture.

When you experience a hip flexor strain, you want to limit the time you’re going to spend on the sidelines. But, don’t worry – you can recover stronger and better than ever. Let’s take a look at what you can do to return to full strength.

The most commonly accepted approach to treatment is the RICE technique (Rest, Ice, Compress, Elevate) which is usually accompanied with an anti-inflammatory to alleviate pain.can improve recovery times significantly.

  • Putting ice packs on the injured area for 20 to 30 minutes every 3 to 4 hours for 2 to 3 days or until the pain goes away
  • Taking anti-inflammatory medications prescribed by your doctor
  • Doing rehabilitation exercises to help you return to your activity.
  • While you are recovering from your injury, you will need to change your sport or activity to one that does not make your condition worse for example you may need to swim instead of bicycling or running.

While this approach is common, it is by no means your only option. We have found that some other approaches can improve recovery times significantly. The downside of ice is that you are potentially working against your body by constricting blood flow and reducing the vital circulation you need to recover. In addition, anti-inflammatories – which are initially potentially effective at reducing swelling, over time mask pain which is not in your body’s best interest (when it comes to recovery).

Keys to recovery include:

  • Increase your circulation - massage therapy. More energy and blood flow means faster recovery.
  • Reduce your swelling. Whether you see it or not, internal and external swelling is the root of your pain and needs to be alleviated.
  • Remove the toxins. Eliminating toxins is essential for a full recovery. Flush out your system by drinking water.
  • Once your hip flexors are healing, we also recommend that you begin lightly using them. Don’t over do it, but a little stretching and strengthening will help reduce swelling and also ensures that new muscle forms properly and scar tissue is broken down and removed.

Prognosis of a hip flexor strain
With appropriate management, patients with a minor hip flexor strain can usually recover in one to three weeks. With larger tears, recovery may take four to eight weeks or longer depending on the severity. Complete ruptures of the hip flexor muscles are rare and are usually managed conservatively. In these cases, recovery may be significantly longer.

Contributing factors to the development of a hip flexor strain
There are several factors which can predispose patients to developing this condition. These need to be assessed and corrected with direction from a therapist. Some of these factors include:
  • muscle weakness (particularly of the quadriceps, hip flexors or gluteals)
  • muscle tightness (particularly of the hip flexors, quadriceps, hamstrings or gluteals)
  • inappropriate training
  • inadequate warm up
  • joint stiffness (especially the lower back, hip or knee)
  • poor biomechanics
  • poor posture
  • inadequate rehabilitation following a previous hip flexor injury
  • decreased fitness
  • fatigue
  • poor pelvic and core stability
  • neural tightness
  • muscle imbalances

Therapy for a hip flexor strain
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
  • electrotherapy (e.g. ultrasound)
  • joint mobilization (especially the lower back and hip)
  • stretches
  • dry needling
  • anti-inflammatory advice
  • the use of crutches
  • ice or heat treatment
  • progressive exercises to improve strength and flexibility (particularly of the hip flexors)
  • education
  • biomechanical correction
  • activity modification advice
  • establishment of an appropriate return to activity or sport plan
Other intervention for a hip flexor strain
Despite appropriate therapy management, some patients with a hip flexor injury do not improve adequately. When this occurs, the treating therapist or doctor can advise on the best course of management. This may include investigations such as an X-ray, ultrasound, CT scan or MRI, or referral to appropriate medical authorities who can advise on any intervention that may be appropriate to improve the condition.

When can I return to may sport or activity?

The goal of rehabilitation is to return you to your sport or activity as soon as is safely possible. If you return too soon you may worsen your injury, which could lead to permanent damage. Everyone recovers from injury at a different rate return to your sport or activity will determined by how soon your hip flexor muscles recover, not by how many days or weeks it has been since your injury occurred. In general, the longer you have symptoms before you start treatment, the longer it will take to get better.

  • You may safely return to your sport or activity when, starting from the top of the list and progressing to the end, each of the following is true:
  • You have full range of motion in the leg on the injured side compared to the leg on the uninjured side.
  • You have full strength of the leg on the injured side compared to the leg on the uninjured side.
  • You can jog straight ahead without pain or limping
  • You can sprint straight head without pain or limping
  • You can do 45-degree cuts, first at half-speed, then at full-speed
  • You can do 20-yard figures-of-eight, first at half-speed, then at full-speed
  • You can do 90-degree cuts, first at half-speed, then at full-speed
  • You can do 10-yard figures-of-eight, first at half-speed, then at full-speed.
  • You can jump on both legs without pain and you can jump on the leg on the injured side without pain.
How can I prevent a hip flexor strain?

Some key principles to follow to prevent future muscle strains include:
  • Try not to compensate for pain or weakness in one muscle group by overusing muscles in other areas. Instead, work to proportionally strengthen all muscle groups relative to your activity, fitness level, and needs. The more balanced your strength and flexibility throughout your body, the better off you’ll be at avoiding injury – and this no more true than in your leg and lower back muscles.
  • If you regularly tax the hip flexor muscles, do what you can to make sure they are both strong and supple. Too much strength and not enough flexibility, or vice versa, will work against you and lead to future muscles tears and muscle pulls, if not even more serious injuries.
  • If you do not regularly tax your hip flexor muscles in your normal exercise routine or sport, incorporate exercises into your strength training routine that seek to strengthen and stretch these important muscles.
  • Warm up properly. Like all your muscles, your hip flexors are more flexible when they are warmed up.
  • Be sure to learn the proper techniques for your sport or exercise of choice. When you know how to perform the movements correctly – particularly which muscle groups to use effectively – not only will your enjoyment and skill level improve, but your chance for injury will dramatically decrease.
  • If you are a cyclist, be sure your seat height is adjusted properly to relieve unnecessary stress on your hip flexor muscles. If you are unsure of the proper height, consult a professional.
  • If you participate in sports that have a high risk of hip flexor injuries (e.g., soccer, martial arts, track and field events), pay special attention to warming up and stretching these muscles appropriately.
  • Stretch AFTER you exercise. When the body is already warmed up, it’s an excellent time to work on your hip flexor (and other muscle) flexibility. This will also help prevent over-tightening as you cool down.
  • Hip flexor strains are best prevented by warming up properly and doing stretching exercises before your activity.
  • If you are a bicyclist make sure your seat is raised to the proper height.

Hip Flexor Strain Rehabilitation Exercises

You can begin stretching your hip muscles right away by doing exercises 1 and 3. Make sure you only feel a mild discomfort when stretching and not a sharp pain. You may do exercises 3, 4, and 5 when the pain is gone.

  1. Hip flexor stretch: Kneel on both knees and place your uninjured leg forward, with the foot resting flat on the floor. From this position, lean forward at the hip and attempt to press your pelvis down toward the floor while slightly arching your back until you feel a stretch at the front of your hip. Hold this position for 30 seconds. Repeat 3 times.
  2. Quadriceps stretch: Stand and hold onto a table or a counter. With the hand on your uninjured side, grasp the top part of the ankle on your injured leg and pull your foot toward your buttock until you feel a stretch on the front of your thigh. Hold this position for 30 seconds. Repeat 3 times.
  3. Heel slide: Sit on a firm surface with your legs straight in front of you. Slowly slide the heel of your injured leg toward your buttock by pulling your knee to your chest as you slide. Return to the starting position. Repeat this 20 times.
  4. Straight leg raise: Lie on the floor on your back and tighten up the top of the thigh muscles on your injured leg. Point your toes up toward the ceiling and lift your leg up off the floor about 10 inches. Keep your knee straight. Slowly lower your leg back down to the floor. Repeat 10 times. Do 3 sets of 10.
  5. Resisted hip flexion: Stand facing away from a door. Tie a loop in one end of a Thera-Band and put it around your injured ankle. Tie a knot it the other end of the tubing and shut the knot in the door near the bottom. Tighten up the front of your thigh muscle and bring your leg forward, keeping your knee straight. Repeat 10 times. Do 3 sets of 10.