Hamstring muscles: outline of anatomy
The hamstring muscles, or simply hamstring or hamstring, are three muscles located in the posterior region of the thigh called respectively: semimebranosus, semitendinosus, hamstring. These three muscles share: origin (ischial tuberosity), innervation (tibial nerve), biarticularity and function (leg flexor and thigh extensor).
Stretching and Tearing of the Hamstrings
Hamstring strains and tears are injuries caused by intense or too abrupt contractions during knee flexion or hip extension. This explains why, the stretching and especially the tearing of the hamstring muscles are more common in centometrists, long jumpers, middle distance runners, tennis players and athletes of other disciplines characterized by sudden jerks, strong decelerations (eccentric work) and abrupt changes of pace.
Causes
To generate movement, the various muscles or muscle groups work in synchrony: when a muscle is shortened, the muscle with the opposite function must relax and stretch in such a way as not to impede movement.
When a kick (leg extension) is performed, the quadriceps muscle contracts and the hamstrings lengthen. The same thing happens when the thigh approaches the abdomen.
On the other hand, when the knee is bent (leg flexion), bringing the heels closer to the pelvis, the hamstrings contract and the quadriceps relaxes.
In many athletes there is a certain imbalance of strength between the hamstring muscles and the quadriceps in favor of the latter. Because of this imbalance, the hamstring muscles tend to tire earlier than the quadriceps. In a tired muscle the muscle tendon organs of the Golgi and the neuromuscular spindles may become ineffective in preventing its excessive lengthening (hamstring stretching / tearing) following quadriceps contraction. This alteration can also prevent the muscle from shortening too much, subjecting its fibers to excessive contractions and predisposing the muscle to localized tears especially in the point where the muscle fibers merge with those tendons (musculotendinous passage).
Symptoms
The tearing of the hamstring muscles is responsible for a violent and sharp pain that arises in the back of the thigh immediately after the trauma.
Other typical symptoms are: pain on palpation, hematoma and tactile perception of a step in the back of the thigh near the injured area (in case of severe injury).
Muscle strains can be classified using a severity scale consisting of three stages (or degrees).
In the first stage, the less severe tears that cause only modest muscle breaks (less than 5% of the fibers) are included; Partial or complete ruptures of the muscle are classified respectively as second and third degree tears.
The symptoms, of course, are all the more severe the greater the number of injured muscle fibers.
First degree injuries are barely noticeable and, apart from slight local hypertonia (muscle contracture), do not normally cause swelling or significant movement restrictions. In the occasion of a second degree hamstring tear, the injury interferes with normal walking, causes pain on palpation and knee flexion movement against resistance and in the last degrees of knee extension. Finally, in third degree muscle tears, the athlete often hears a noise similar to a snap at the time of the injury; in these cases, moreover, the pain is particularly intense and the affected subject, who generally tends to collapse immediately to the ground , is forced to walk with the help of crutches.
Diagnosis
For the diagnosis of a hamstring strain or tear, information from a hamstring exam is very important. imaging, such as muscle-tendon ultrasound or magnetic resonance imaging; as well as for diagnostic confirmation, these instrumental tests allow the doctor to establish the exact extent of the muscle injury.
Treatment
In the acute phase of the trauma (first two or three days) apply the R.I.C.E protocol (rest, elevation, compression, ice).
Anti-inflammatory drugs may be helpful in this early stage to reduce pain and inflammation.
After three to five days, as the pain and swelling subside, it is important to start a program of strengthening and strengthening exercises. stretching. The strengthening of the hamstrings, in fact, is necessary to prevent the chronicization of the lesions. However, it is important to gradually increase the intensity of these exercises: in the initial phase, for example, it is necessary to work with moderate loads and a high number of repetitions; in this way the local inflow of blood, oxygen and nutrients will be favored, facilitating the regeneration process and limiting the formation of scar tissue. Among the most useful physical therapies we mention ultrasounds and therapy.
Surgery is only necessary in the most severe cases or when the lesions become chronic.
Prevention
- Always perform a general and specific warm-up of the muscles
- Make sure you are in the right physical condition to withstand the effort
- Carefully evaluate the practicability of the pitch
- Choose suitable clothing, cover up well in the winter months and, if necessary, use specific ointments during the heating phase
- Always perform stretching exercises to improve muscle elasticity and flexibility both in the preparatory and in the relaxing phase
