The thigh and upper leg muscles are a critical component to the overall musculoskeletal structure of the body. The upper leg is composed of the femur (thigh bone), the longest and the heaviest bone in the skeleton, which forms a part of the hip joint at one end, and the knee joint at the opposing end. The femur supports the quadriceps (thigh muscles), a group of four powerful muscles positioned on the front of the thigh that are primarily responsible for the extension motion of the knee. The quadriceps is attached at the knee joint to the tibia (shin bone) by way of the quadriceps tendon.
The muscle and tendon that are responsible for the knee's opposing flexion (bending action) are the hamstrings. The hamstring tendon is also connected to the tibia, immediately below the rear of the knee joint. In most sports, the ideal ratio in the relative strength of the quadriceps to the hamstring is 3:2. Significant imbalances in this strength ratio can lead to significant injury in one or both of the muscle groups.
The upper thigh muscles are connected to the abductors (located at the upper and inner aspect of the thigh) and the groin muscles of the lower abdomen, which assist in both the stabilization of the body and the movement of the upper legs; the strength in these muscles forms a significant part of the core strength of any individual. At the rear of the upper thigh, the femur and connective tissues are supported by the gluteal muscles (buttocks). From the illiol bone of the hip to the tibia of the lower leg, the iliotibial (IT) band extends, constructed of a fibrous and thickened soft tissue material, called fascia, that provides stability to the entire upper leg.
One of the most common upper leg and thigh injury is a muscle or tendon strain, which can occur in any of the large muscle structures between the knee and the hip. A strain is an overextension of the muscle fibers that comprise the muscle organism, caused by either a repetitive movement or an imbalance in the relative strengths of the hamstring and the quadriceps. A strained tendon, often referred to as a "pull," frequently occurs in the hamstring, especially when the athlete moves explosively to accelerate. In some cases, certain of the long, cylindrical muscle fibers, which may number in the thousands, may be microscopically torn, without a rupture or other more serious damage to the muscle. Muscle strains are categorized according to their severity. A grade 1 strain produces a cramping or tightening sensation in the affected muscle. An athlete can often continue in a competition if the injury is immediately treated, provided that the athlete understands that the strain may become aggravated with continued stress directed into the tissues.
A grade 2 muscle strain will produce an immediate and pronounced pain in the region of the injury, and the athlete will usually not be able to continue in competition after the injury is sustained. A grade 3 strain is characterized by an immediate and direct stabbing sensation in the injured muscle. This injury will incapacitate the athlete until the damage to the tissue is healed.
Another common injury to the quadriceps is caused by a direct blow to the muscle. As a large prominent structure, the thigh is exposed to a considerable variety of traumas, most of which result in a contusion, creating swelling, bruising, and a limitation of movement and flexibility. Athletes in sports that involve the blocking or tackling of an opponent, and those sports that create incidental contact between opponents, such as soccer and basketball, frequently sustain these injuries.
All soft tissue injuries in the thigh or upper leg can be effectively treated in their initial stages with the RICE (rest/ice/compression/elevation) treatment method. Given the size of the quadriceps and hamstrings, the compression element to the RICE progression must be especially thorough. It is estimated that over 90% of these injuries can be resolved conclusively through RICE, or using the treatment in conjunction with the administration of a nonsteroidal anti-inflammatory drug (NSAID) to relieve pain and inflammation.
The most serious injury to the thigh or upper leg is a facture of the femur. In an adolescent person, this injury can be particularly worrisome if it affects the growth plate, the soft area of bone located at the epiphysis near the head of the femur, as the fracture may interrupt the proper growth of the bone. In an adult, a fracture is a debilitating injury that will often require surgery to insert one or more pins into the bone to provide it with support. Both injuries are caused by significant force being directed into the bone, such as may occur in a high speed collision.
Sports science research regarding the incidence of thigh and upper leg injuries has repeatedly identified a lack of stretching and flexibility in the athlete as a significant contributing factor to their causation. Stretches that promote harmony between the quadriceps, hamstrings, IT band, gluteal muscles, and groin will provide both greater inherent stability in movement and reduced risk of musculoskeletal injury in the structures.