Hamstrings injuries

The importance of hamstrings for sport and everyday life

The Back of the thigh is responsible for numerous movements that are required in sport as well as in everyday life. The hamstrings are particularly active during explosive movements such as sprints, jumps, quick changes of direction or kicking movements. They also provide stability and control the movement of the leg when walking and standing. A healthy and strong Biceps femoris and the other hamstring muscles are therefore essential for optimum freedom of movement and pain relief.

A recent meta-analysis of 5,952 documented injuries shows that Hamstring injuries account for around 10 % of all injuries in field-based team sports (Maniar et al., 2022). The strain is particularly high in football, where the hamstrings account for between 5 and 15 % of all injuries. The re-injury rate is alarmingly high at up to 68 % (Diemer et al., 2021). These figures illustrate the importance of targeted prevention and rehabilitation for the Back of the thigh are.

Anatomy of the back of the thigh: focus on the biceps femoris

The Hamstrings are made up of three muscles: Biceps femoris, Semitendinosus and Semimembranosus. They originate on the ischium (ischial tuberosity) and attach to the lower leg. The Biceps femoris runs along the outer side of the back of the thigh and attaches to the head of the fibula (caput fibulae). The other two muscles attach to the inside of the tibia. All three muscles are biarticular, i.e. they cross both the hip and knee joints. This allows them to extend the hip, bend the knee and rotate it - functions that are essential for athletic performance and everyday movements.

Why are the hamstrings so susceptible to injury?

The high susceptibility to injury of the Back of the thigh can be explained by various factors. The hamstrings transmit enormous forces between the leg and torso during fast movements. They are particularly challenged during explosive actions such as sprinting, abrupt braking or rapid changes of direction. Most Hamstring injuries occur without direct contact - usually in the transition between muscle and tendon, often during sprinting or maximum stretching.

The Biceps femoris is particularly frequently affected: Up to 80 % of all hamstring injuries affect this muscle (Gronwald et al., 2022). Another risk factor is an imbalance between the anterior and posterior thigh muscles. If the muscles on the back of the thigh are too weak or too shortened compared to the quadriceps, the risk of muscle injuries increases significantly.

Typical symptoms and diagnosis of hamstring injuries

A sudden, stabbing pain in the Back of the thigh is the classic symptom of an acute hamstring injury. Those affected often report a "clicking" or "tearing" sensation during exercise. In the case of a torn muscle fiber, mobility is usually restricted immediately, while overloading tends to lead to dull, pulling pain. Swelling or bruising can also occur.

A precise medical diagnosis is important to determine the type and extent of the injury. In addition to the clinical examination, imaging such as ultrasound or MRI can be useful to detect muscle fiber tears or tendon involvement. Complaints without a clearly recognizable traumatic cause should always be carefully investigated by means of a differential diagnosis.

Hamstring rehabilitation: safely back to activity

After the diagnosis of a Hamstring injury rehabilitation should begin as early as possible. The aim is to restore the freedom of movement of the Back of the thigh and minimize the risk of re-injury. A task-based approach has proven its worth, as the requirements vary depending on the type of sport and the extent of the injury.

Rehabilitation is divided into several phases that are individually adapted:

• Acute phase: Pain relief and anti-inflammation are the main focus. Weight-bearing is reduced, but complete immobilization should be avoided.

• Build-up phase: Gradually increasing the load, targeted strengthening exercises for the hamstrings and in particular the Biceps femoris. In addition, exercises for core stability and the gluteal muscles are integrated.

• Sport-specific phase: Getting back into running and sprint training, improving movement coordination and agility.

• Return-to-play: Increase the level of exertion until full resumption of sporting activity, always under control of the pain intensity (ideally below 4/10 on the pain scale).

It is important that the exercises are individually adapted to the patient's needs and goals. Close supervision by experienced physiotherapists supports a safe and effective return to activity.

Prevention: How to protect the back of your thighs

To prevent injuries to the Hamstrings and the Biceps femoris a balanced training program is recommended:

• Regular strength training for the Back of the thigh, to compensate for muscular imbalances.

• Targeted stretching and mobilization before and after intensive exercise.

• Thorough warm-up before training and competition.

• Optimization of running and sprinting technique as well as exercises to improve core stability and agility.

Prevention is particularly important for footballers and runners, as the strain on the body's muscles can be very high. Back of the thigh is particularly high in these sports.