Hamstring: the most prevalent injury among sports enthusiasts

Muscle injuries are among the main concerns in sports related injuries, especially in elite teams. Hamstrings are the most common muscles to be injured and are unique in their kind – Dr. Omar Mustafa, Physiotherapist at Canadian Specialist Hospital, Dubai.

They are located in posterior thigh muscles, between the hip and the knee and they include 3 different muscles which are semimembranosus, semitendinosus and biceps femoris. They are highly involved in the motion of the knee and the hip.

Injuries can be classified based on MRI findings from grade 0 to grade 4 injuries.

• Grade 0 injury indicates presence of clinical symptoms and the average time to return to play would be 1-2 weeks.
• Grade 1 injury signifies less than 10% of the muscle cross section damage and usually takes 2-3 weeks to return to play.
• Grade 2 injury is between 10% to 50% of muscle damage with 4-6 weeks’ time to return to play, whereas, grade 3 is more than 50% muscle damage with 5-8 weeks of time for recovery.
• Lastly, grade 4 injury signifies complete tear of the muscle and in this case, timings are indicative and may vary.

Hamstrings can be injured mainly in 2 ways, i.e. due to violent contraction while bending the knee, such as, during the pushing phase of the run, or most commonly when the muscle is stretched, in order to brake the extension of the knee in the slowing down phase of the run or after shooting.

The rehabilitation process should start immediately, but the best practice to follow is still under debate. “Generally, in the early phase we reduce the swelling by wrapping the muscle with an elastic band, apply ice and keep the limb elevated to ease the return of blood. At this stage, we also apply anti-inflammatory cream and prescribe pain killers to fight symptoms. After few days of inflammatory phase, the real rehabilitation phase begins, being aimed at optimizing the healing process and reducing the impairment of the eventual scar inside the muscle which is considered an important cause of re-injury”, added Omar.

Physiotherapy at this stage includes gentle stretching, segmental contraction and modalities such as ultrasound therapy, laser therapy, TECAR therapy, and shock wave therapy. After the healing phase, and sometimes also during its course, the player is reintroduced into the field to examine the recovery by jogging, running and sport related specific activities to restore the coordination and flexibility of the muscles.

Recent studies have given rise to proposed adjuvant treatments that may enhance muscle healing, decrease fibrosis, and provide a smoother transition back to competition. Proposed treatments include intramuscular or myotendinous junction steroid injections, PRP (platelet-rich plasma) and ACS (autologous conditioned serum injections), angiotensin II receptor blockers such as losartan, and muscle-derived stem cells. As of now, the results of studies proposing these treatments appear promising. However, more studies are required in order to better determine their efficacy and allow for their use in clinical practice.