The knee is the most complex joint in the body and has a wide range of movements. The National Institute of Arthritis, Musculoskeletal and Skin Diseases notes that it is also the most likely to be injured because it is one of the most used joints and it bears the weight of the body during sitting, standing and other movements. The structure of the knee is important for its wide range of function. The knee joint is able to flex, extend and also rotate slightly.
Bones and Muscles
The knee is made up of four bones: the thigh or femur bone, the tibia or lower leg bone, the fibula which runs parallel to the tibia and the knee cap or patella. The bones of the legs are bound together at the knee joint by muscles, cartilage, tendons and ligaments. The main muscles that support the knee are the quadriceps muscles that extend from the thigh to the front of the knee and the hamstrings that run from the back of the thigh to the back of the knee joint.
Ligaments
The ligaments of the knee are important to bind and stabilize the joint. The four main ligaments of the knee joint are the medial collateral ligament or MCL, the posterior collaterol ligament or LCL, the anterior cruciate ligament or ACL and the posterior cruciate ligament or PCL. LightPhysio.com explains that the cruciate ligaments run diagonally in opposite directions along the joint, forming an ‘X.’ The ACL holds the tibia bone of the lower leg in place from the front of the knee joint while the PCL prevents backwards movement of the tibia. The cruciate ligaments are very important in strengthening the knee and preventing dislocation during jogging, running, kicking and other high impact movements. The MCL and LCL stabilize the knee from the outside on both the inner and outer sides of the joint.
Knee Nerves
The Chester Knee Clinic in the U.K. explains that specialized nerves in the knee joint allow sensory orientation of the joint so that individuals can coordinate movements, such as walking, running, standing and sitting. If the knee joint is injured or damaged, the nerves may be affected, which can cause pain as well as a loss of positioning. This can affect balance and natural movement. Physiotherapy exercises help to heal the nerves and retrain the position receptors of the knee.
Knee Injuries
The knee joint is susceptible to pain, injuries and damage from wear and tear, overuse, arthritis, falls, accidents and sports injuries. The anterior cruciate ligament is the most commonly injured part of the knee. Injury to this ligament usually occurs if the knee joint is suddenly pivoted or jerked while the foot remains stationary. The National Institute of Arthritis, Musculoskeletal and Skin Diseases note that damage, injuries, sprains and tears or ruptures of ligaments and tendons are common causes of pain and swelling of the knee joint. Diseases that degenerate the bone and cartilage in the knee also cause pain, inflammation and swelling in the joint. These include conditions such as rheumatoid arthritis, osteoarthritis and osteoporosis or loss of bone density. The patella, or knee cap, can also become injured, damaged and completely or partially dislocated due to accidents, injuries or weakened knee structures.
Knee Joint Injury Treatments
Treatments for knee joint damage and injury include medication, icing the area, rest, physiotherapy exercises and surgery. Physical therapy is an important part of treatment for pain and damage that affects knee function and to help recovery after knee surgery. The Chester Knee Clinic recommends a diverse range of weight-bearing and motion exercises to improve knee function and rehabilitation of the joint. Physiotherapy helps to strengthen the muscles and ligaments to improve joint health and flexibility. According to research published in the British Medical Journal, physical therapy exercises help to improve knee pain and movement after surgery.
References
- Chester Knee Clinic & Cartilage Repair Centre: Rehabilitation
- British Medical Journal: Effectiveness of Physiotherapy Exercise After Knee Arthroplasty for Osteoarthritis: Systematic Review and Meta-Analysis of Randomised Controlled Trials
- National Institute of Arthritis, Musculoskeletal and Skin Diseases: Knee Problems
- Light Speed Physio: Physiotherapy for Knee Injuries & Knee Pain
