Knee Injuries & Common Causes of Knee Pain

Physiotherapy is a widely used method of treatment for a range of knee injuries – providing an effective method of rehabilitation and pain relief.

The knee is an extremely complex joint, this modified hinge joint is one of the largest in the body, and a type of synovial joint. Three bones meet at the knee joint: the femur (thigh bone), the tibia (shin bone) and the patella (also known as the kneecap). The patella is a free-standing piece of bone which articulates with the femur as well as protecting the surface of the anterior knee joint. The knee joint is held in position and stabilised by a network of ligaments, tendons, muscles and joint capsule. It has a very important function, it not only allows full extension and flexion of the leg, but also supports the weight of the body.

The complex nature of the knee joint, as well as the constant strain put upon it due to movement and load, makes it more susceptible to injury and general wear and tear. Knee pain is a common occurrence, with a high percentage of the general population suffering from knee related discomfort at some point in their lives and it becomes even more prevalent in those who regularly engage in particular sporting activities.

knee injuries

Common Causes of Knee Pain

Knee pain can occur as a result of a number of different factors including trauma/injury, misalignment, over-use injuries, degeneration and arthritis.

Torn Ligaments and Tendons

A high percentage of injuries to the knee occur as a result of damage to the ligaments, tendons or cartilage. The soft tissues of the knee are what bind the joint together, the ligaments – tough bands of tissue, serve to connect bones to one another and the tendons connect muscle to bone.

Injured ligaments and tendons are usually categorised as sprains and graded on a level of severity from 1 to 3. Grade 1 describes mild damage to the ligament, Grade 2 describes severe stretching of the ligament and is often referred to as a partial tear, and Grade 3 describes a complete tear of the ligament.

ACL (Anterior Cruciate Ligament) Injuries

The ACL is one of two cruciate ligaments which run diagonally down the front of the leg, crossing in the middle of the knee. They connect the femur to the tibia and help stabilise the knee. The anterior cruciate ligament attaches at the front and back of the knee and the posterior cruciate ligament crosses to also attach at the front and the back. They are called “cruciate” as they cross over each other.

Injuries and tearing of the ACL are frequently seen in individuals engaged in contact sports such as football, rugby, basketball, skiing, etc. Tearing or damage to the ACL is usually caused by suddenly changing direction, twisting the legs and knees while the feet are firmly planted on the ground, or direct impact to the knee from a blow or during a collision, falling or landing poorly from a jump.

Symptoms of ACL injuries may include the following:

ACL injuries often occur with damage to other ligaments and tendons in the knee, causing severely painful symptoms. If ACL injury is suspected your doctor, consultant or physiotherapist may require diagnostic testing such as an MRI scan, X-Ray, or Ultrasound scan to rule out the possibility of any other conditions such as a fracture.

Treatment is usually in the form of rest, elevation, ice packs and the use of anti-inflammatory medicines to help treat the initial swelling.

Physiotherapy is the best method of rehabilitation, targeted exercises can reduce pain and swelling as well as restoring movement and strengthening the muscles.

In some ACL injuries, surgery may be recommended depending on the signs and symptoms.

Posterior Cruciate Ligament (PCL)

Posterior Cruciate Ligament (PCL) tears are of a similar nature to ACL injuries, these often occur as a result of a direct blow to the front of the knee during sporting activities or in an accident. In most cases PCL injuries tend to be partial tears at the worst, which usually resolve themselves with self care measures and specific exercises.

Collateral Ligament Injuries

Collateral ligaments are found at the sides of the knee – the Medial Collateral Ligament (MCL) connects the femur to the tibia, and the Lateral Collateral Ligament (LCL) connects the femur to the fibula (the smaller bone in the lower leg). These ligaments help to stabilise the knee and protect it from sideways motion. Any tears or sprains to either collateral ligaments are usually a result of a direct blow to the outside of the knee, or due to a twisting force and can be treated with pain relief medication, physiotherapy and rest when required.

Meniscal Tears and Cartilage Damage

The knee contains two different types of cartilage, Meniscal cartilage and Articular cartilage – the latter covers the ends of the femur, tibia and patella preventing the bones from grinding against one another and assisting in smooth motion. Injury and damage to cartilage in the knee however, usually refers to meniscal cartilage.

The menisci consist of two disc shaped pieces of cartilage positioned between the femur and the tibia, they act as shock absorbers and help to keep the knee stable. Meniscal tearing in the knee often occurs as a result of sporting activities – especially during contact sports. It can also however, be due to degenerative changes –  as we age our cartilage thins, becoming more prone to wear and tear.

Symptoms of a meniscal tear may include the following:

Mild damage to the meniscal cartilage will usually resolve itself with pain relief medication, rest and gentle exercises. More severe damage however will not and should not be left untreated.

Rehabilitation with physiotherapy and one of a number of possible surgical techniques, may be used in more severe cases.


Tendonitis refers to inflammation of the tendon, this can occur in any part of the body – in the knee it is known as Patellar tendonitis, also referred to colloquially as ‘jumper’s knee’ – a relatively common overuse disorder of the knee, frequently seen in physically active middle-aged individuals and may be due to degenerative changes to the tendon. Symptoms may include localised pain and swelling as well as difficulty moving.

Patellar tendonitis may be the result of a sudden sharp movement or impact, or repetitive over use. Physiotherapy and pain relief medication are usually the first treatments, in more severe cases surgery may be required.


The bursae are small fluid filled sacs which serve to cushion the knee joints, as well as allowing the ligaments and tendons to glide easily over the joints. Bursitis occurs when any of the bursae in the knee become inflamed, it most frequently occurs on the inner side of the knee below the joint and over the knee cap. Bursitis can be a result of physical activity, osteoarthritis or infection. Symptoms are usually described as sensations of pain, swelling and of localised heat.

Physiotherapy can help improve flexibility as well as improving strength and range of motion. Other treatments include pain relief medication, corticosteroid injections, and in more severe cases surgery.


When the bones of the knee move out of alignment or slip out of place, dislocation occurs, causing painful and debilitating symptoms. In the majority of cases this is caused by heavy impact such as a fall, accident or sports related contact. In rarer cases, it may the result of a pre-existing abnormality to the structure of the knee.

Dislocation can also cause damage to the surrounding soft tissue structure, making recovery a longer process.

Physiotherapy techniques are used to help regain a normal range of motion whilst the knee is healing, the exercises will help to rehabilitate weakened muscles and strengthen the knee, helping to keep it stable.


A fractured patella is a break or crack in the patella. It is often caused as a result of direct impact such as in a car crash, or a fall or during contact sports.

Symptoms of a patella fracture include:

Imaging will be required to confirm the diagnosis, such as X-Ray.

In the case of a simple fracture, use of a cast or splint to keep the bone stable while it heals should suffice. Physiotherapy will be required as part of the healing process to strengthen and rehabilitate the surrounding tissues.

In many cases, however the fracture is more complicated and causes a piece of bone to move out of place, in these instances surgery is usually required to put the pieces of bone back together.

Physiotherapy will play a vital role in regaining a full range of motion and strengthening the surrounding soft tissue structures.

Degenerative Changes – Osteoarthritis

As we age our bodies are subject to degenerative changes as the wear and tear repair cycle begins to slow down and deteriorate. Osteoarthritis in the knee is common, with a gradual onset of symptoms including pain, stiffness and swelling. It typically involves the breakdown of cartilage in the knee and the subsequent growth of osteophytes – bony growths which develop in response to the degeneration of the cartilage.

The onset of osteoarthritis in the knee is slow and is influenced by a number of factors such as genetics, age, weight and healthy living. Maintaining a healthy weight and lifestyle are extremely important in the prevention and management of osteoarthritis – physiotherapy is an integral component in the treatment of knee osteoarthritis, helping to strengthen and improve flexibility.

Contact ProPhysiotherapy

ProPhysiotherapy offer a team of highly skilled professional physiotherapists, specialising in the management and rehabilitation of knee related complaints –  our treatment is based on well-established techniques, supported by academic research. We tailor our treatment programmes to suit individual requirements, providing our patients with support as well as educating on how to manage and improve symptoms. For more information, get in touch today. Earlsfield: 020 8879 1555 Wimbledon: 020 8946 2800


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