By Lauren Belza
Hamstring strains are one of the most common soft tissue injuries. Unfortunately these tears can sideline athletes for 2-6 weeks, depending on the severity and location of the tear. The hamstrings refer to a group of muscles of the posterior thigh (biceps femoris, semimembranosus and semitendinosus) which allow us to complete knee flexion and hip extension, predominantly. These muscles are therefore more prone to tears due to the fact they are bi-articular (crosses two joints). When the forces demanded of the hamstrings are greater than their ability to cope, a tear occurs. The majority of tears (83%) occur within the biceps femoris which is the most lateral of the hamstring muscles. 
If left un-treated hamstring tears can become a recurring niggle injury which never seems to truly go away. Research has found poor management of these injuries can see up to one third of athletes experiencing a tear within the initial two weeks following return to sport.
Clinical presentation:
The majority of hamstring tears typically occur in running sports which require high power and speed i.e. AFL, basketball, hockey or soccer. An athlete will feel localised pain in the hamstring region, mid stride of their run, generally disabling them from continued play.
A rarer mechanism of hamstring injury can occur during gymnastics or dance whereby an individual places excessive stretch upon their hamstrings i.e. splits.
It’s important to understand the mechanism of injury as healing time, rehabilitation and return to sport can vary immensely between the two types of tear and the severity (grade) of the tear. 
These are the usual signs and symptoms of an acute hamstring tear:
• Sudden onset during a particular activity i.e. running or completing the splits
• Localised pain within the posterior thigh
• Pain with walking and difficulty running
• Localised bruising or swelling over the posterior thigh
• Reduced strength with contraction
Risk Factors:
• Biomechanics
o Studies have identified the hamstrings are biomechanically vulnerable during the terminal swing phase of running due to the high eccentric force required of them to decelerate the lower leg for foot strike. This is why rehabilitation focus has shifted in recent years to focus on eccentric loading exercises to specifically strengthen the muscles to overcome this biomechanical flaw.
• Past injury history
o Previous injury and poor adherence to a previous rehabilitation program results in adverse physiological changes i.e. neuromuscular inhibition, reduced strength, scar tissue and altered muscular recruitment.
• Lumbar spine
o Tightness in structures in the lumbar spine or gluteal region can cause referred pain, poor activation of muscles, or excessive tightness in the hamstring muscles
• Physiological
o Older age, increased BMI, reduced flexibility and muscular imbalances.
• Sport and position
o High intensity, speed and power
• Training load
o Reduced recovery, inappropriate warm-up/cool downs, increased loads
Rehabilitation:
Our physiotherapists will take you through an individualised rehabilitation program, tailored to meet your sporting needs and injury. An emphasis is placed upon manual therapy, strengthening program and progression through key functional sport specific skills, ensuring a safe and appropriate return to sport.
Management of hamstring rehabilitation needs to be specific to the stage of the injury:
Acute phase-settle inflammation and pain:
• RICE
• Isometrics
• Gentle Range of motion
Sub- acute- Strength and Neuromuscluar control:
• Hamstring curls
• Eccentric loads
• Pelvic/gluteal control
• Jogging/running
Return to sport- specific drills:
• Sports specific agility
• Plyometrics
Prevention- reduce recurrence rate:
• Eccentric exercises
• Mobility
• Correct warm –up procedures
Prevention:
Adherence to a tailored rehabilitation and continued self-management is crucial in reducing your risk of future injury and ensure you don’t spend more time on the sidelines. Research has identified eccentric loading exercises of the hamstring can significantly prevent new and recurrent hamstring injuries. These exercises are shown in the following videos; arabesque, Nordic curls.
It is important to have all of the other risk factors to hamstring injuries identified, so if you have suffered a hamstring strain or would like a specific prevention program put in place contact your closest Physiohealth clinic.
References
Brukner. P, & Khan. K. (2016). Clinical sports medicine (5ed.). New South Wales: McGraw Hill education
