Hamstring injuries are a common and frustrating issue for sportspeople. One of the first questions asked by my patients is, ‘When can I play again?’ This depends on numerous factors, as we need to ensure a safe return with a low risk of short and long term re-injury. This article will discuss the factors that go into quick and effective rehabilitation.
Quick anatomy lesson
The hamstring is a group of three muscles at the back of the thigh. It’s a crucial muscle for all sports, but particularly for running, sprinting and kicking sports. The most common time for a tear to occur is during deceleration and the overstretching mechanism when kicking. The pain is often sudden and always specific to the area at the back of the thigh (posterior).
Figure 1. The 3 muscles comprising the hamstring – Biceps Femoris, Semitendinosus, Semimembranosus (Posterior View).
Hamstring injuries can be classified as Grade I, II or III, with I being a mild strain on the muscle fibers, II being a moderate tear and III being a complete rupture of the muscle. On average, hamstring injuries result in a 17-day absence from sports. This is only an average though, as it depends on the severity of the injury and the factors that caused the injury.
Fig 2. Grade I Hamstring tear in the biceps femoris
Factors that lead to hamstring injury:
- Age: Increased risk for older athletes
- Prior history of hamstring injury
- Insufficient or incomplete rehabilitation for a prior injury may increase chance of re-injury soon after
- Muscle overload: Including sudden load or insufficient muscle warm-up
- Poor flexibility of hamstring and/or quadriceps (particularly amongst office workers)
- Strength imbalance between hamstring, glutes and quad muscles
- Muscle fatigue
- Poor running mechanics and/or gait
- Weak core and trunk stabilisers
- Tightness in the lower back
- Poor single leg balance
Planning a successful return to sports
Assessment – Accurate diagnosis is paramount. This will guide what grade the tear is. The next stage is understanding the causes. This may not be possible in the first session, but as comfort allows, the therapist must understand what factors lead to the injury, so we can target them and prevent the injury from happening again.
Patient education – I find empowering and informing the patient to be the most crucial part of any injury and its rehabilitation – a thorough discussion on what the injury is, what factors caused it and how we are going to fix it. It is my job as a physiotherapist to ensure that the patient and I are on the same page. This will always allow a faster recovery, a reduced chance of re-injury, and hopefully a more body-aware patient in the future.
Soft tissue healing – All therapists have slightly different takes on what ‘hands on’ or manual therapy is best to promote healing. Essentially, the aim is to reduce the swelling within the muscle for a more effective scar tissue formation.
Stretch – Stretching should be done with caution. I encourage patients to regain the normal length of their muscle, but stretching should not be the focus of the rehab.
Movement – Ensuring the paitient is mobile and walking normally is important. It has to be comfortable and pain free, though. Any pain during early mobilisation could be harmful.
Addressing the underlying causes – This may include restoring the flexibility of the lower back, improving single leg balance and fixing any postural factors that are overloading the hamstring muscle.
Strength and conditioning – Current evidence states that strengthening should not be isolated to the hamstring muscle. Strengthening the injured hamstring is crucial and reasonably simple. The Nordic strength protocol has been widely regarded as the most effective in clinical practice. However, it should not be strengthened in isolation. Better outcomes have been found with extra attention to core and trunk stability, as well as the gluteal muscles. This ensures the muscles around the core maintain a strong foundation on which the hamstring muscle can work from.
Functional rehabilitation – This is where rehabilitation succeeds or fails, in my eyes. It can be the stage when people return to full activity because they feel okay, but are not yet ready for the demands of their sport. Functional training will ensure that you train the same movement patterns that your sport or activity requires, while addressing any errors in movement technique. A great therapist will ensure you correct any technical flaws, with the aim of preventing future injury. In my eyes, this is the most enjoyable and rewarding part of the rehab process.
Fig 3. Examples of eccentric lengthening exercises
Returning to sports
What does the evidence say about returning to sport early, and with less risk of injury?
Eccentric strength – Lengthening exercises that promote greater strength in the muscle. Reduces return to sport time.
Early running and stretching – Pain-free early running and stretching are important in a quicker return to play.
Core and trunk stability – Will reduce the re-injury rate.
PRP injections – not effective. This is uncommon in the general population for hamstring injuries, but used more amongst elite sportspeople.
So when do I know it’s safe to return?
Your therapist will guide this process. Unfortunately, you can’t simply return once the pain is resolved. A return to sports is only possible when a series of tests are pain free and functional (performed with proper technique). These tests include progressions from basic muscle activation testing, controlled movements like lunges/squats and basic jogging, all the way to sports-specific, power and explosive based actions. If a patient can perform these tasks, especially during some fatigue, then it can be deemed safe to return to training for a game simulation scenario.
Hamstring injuries can be caused by many factors. A good therapist is able to identify these issues for a faster and more successful return to sports. Eccentric lengthening exercises and core stability are crucial to reducing the risk of future injury.
Problems with hamstring injuries?
Thanks for reading!
This post has been written by PhysioActive physiotherapist Joel Bates.
Thoughts or questions?