What is it?
The hip flexors are a group of muscles that move the hip forward when running and walking. A great deal of stress is applied to this muscle group when sprinting and kicking. Over the last 3-4 years this injury has become fairly common in the media, as professional athletes often sustain it. You will hear announcers mention it as "... he's going to be unable to play today due to a hip flexor." Well actually, we all have "hip flexors", it's those with a hip flexor strain that have a problem. A strain can vary anywhere from stretching to a complete tear of the muscle tissue.
It hurts where?
All of the hip flexors are primarily located on the anterior upper thigh or hip. There are 6 main muscles involved with hip flexion and it can be very difficult to distinguish which of them is actually injured. Considering their location it makes sense that pain will always occur on the anterior upper thigh/ hip. Symptoms will be associated with actions that move the leg forward or upward.
How does it happen?
Freqently a hip flexor strain is the result of an overly forceful contraction. This can occur during a sprint or a series of sprints. Soccer players are at high risk for this injury due to the powerful kicks associated with crossing passes, corner kicks, and shots on goal. The strain can also be the result of overuse (kicking/ sprinting) and associated "micro traumas". A micro trauma can be considered a tiny imperceptable tear. These tiny tears accumulate over time and eventually result in a strain and pain.
Injury Progression ...
Generally, a 1st degree strain involves stretching (or very minor tearing) damage to the muscle or tendon. A 2nd degree strain is associated with partial tearing of the muscle or tendon. And, worst case scenario, a 3rd degree strain is a complete tear. Regarding injury progression, playing with any strain can easily lead to further damage and function loss. This is particularly true when the injury is related to overuse and has a gradual onset. Athletes often try to play through this, with no rehabilitation, and it results in a grade 1 strain becoming a grade 2.
Similar Injuries:
Most often, a hip flexor strain can be confused with a groin strain (adductor strain). This is because the athlete will have pain on the anterior- medial hip. One differentiating factor is adductor strains cause pain with lateral movements (cutting), and hip flexor strains do not. It is possible to involve both muscle groups in an injury though. A quad strain will also present with symptoms similar to a hip flexor strain.
Treatment:
As always, ice bags over the painful area for 20-25 minutes after training is a good place to start. At Stockton we focus on the following, a gradual strengthening the all the hip musculature, working on proprioception (various balancing skills), and increasing flexibility (including hamstring & adductors). Time off from aggravating activities may also be necessary, but this depends on the severity of the injury and when rehabilitation has begun.
Participation Status:
Athletes with a grade 1 strain can usually continue to participate as tolerated, implementing ice and rehabilitation. Athletes with a grade 2 injury will require some time off and rehabilitation. Time missed can vary from a few days to a few weeks here. Grade 3 hip flexor injuries are rare and will probably be season ending.
http://www.stockton.edu/ospreys/HipFlexorStrain.htm
