Patellofemoral Pain Syndrome
Pain arising from the joint between the knee cap (patella) and thigh bone (femur) causing pain at the front of the knee. Typically in association with excessive activity such as squatting, lunging, jumping, running or kneeling and abnormal alignment of the knee cap. Associated with pain on firmly touching the patellofemoral joint (i.e. edge of the knee cap) and occasionally a grinding sensation behind the knee cap. Arguably the most common cause of pain at the front of the knee.

Medial Meniscal Tear
Damage to cartilage located at the inner aspect of the knee joint (medial meniscus) usually due to carrying excessive weight or twisting. Pain is usually located at the inner knee and often increases on firmly touching a specific area of the inner knee joint line. A clicking, catching or locking sensation may also be present. Symptoms are usually exacerbated with excessive weight, deep squatting and twisting activities.

Lateral Meniscal Tear
Damage to cartilage located at the outer knee joint (lateral meniscus) usually due to excessive weight bearing or twisting forces. Pain is usually located at the outer aspect of the knee and often increases on firmly touching a specific area of the outer knee joint line. A clicking, catching or locking sensation may also be present. Symptoms are usually exacerbated with excess weight, deep squatting and twisting activities.

Knee Arthritis
A degenerative process whereby there is gradual eroding of the surfaces of the knee joint with subsequent inflammation. May occur following a specific injury or, more commonly, due to repetitive forces going through the knee over a period of time. There is usually stiffness or loss of range of movement in the knee, swelling and sometimes an associated limp or clicking/grinding sensation during certain movements. Pain may be located at the front, sides or back of the knee and is typically aggravated by weight bearing activities. Pain may also increase on firmly touching the knee joint line. More common in older patients.

Patella Tendonitis
A condition characterised by tissue damage and inflammation to the patella tendon resulting in pain at the front of the knee just below the knee cap. Usually an overuse injury resulting from repetitive running, jumping, squatting or kicking activities. Pain is usually experienced on firmly touching the patella tendon and swelling or puffiness may be present. Pain may also increase when performing a single leg squat or when stretching the quadriceps muscle.

Iliotibial Band Syndrome
A common injury in runners causing damage and inflammation to tissue located at the outer aspect of the knee due to rubbing of the iliotibial band (ITB) over the bone prominence situated at the outer aspect of the knee (femoral epicondyle). Associated with pain on firmly touching the femoral epicondyle at the outer aspect of the knee.

Fat Pad Impingement
Compression of fatty tissue located at the front of the knee directly below the knee cap, usually due to repetitive knee hyperextension activities (e.g. standing with knees hyperextended). Typically associated with significant pain, pain on firmly touching the region directly below the knee cap on either side of the patella tendon and exacerbation of symptoms during knee extension activities.

Baker’s Cyst
A condition characterised by local swelling situated behind the knee typically as a result of knee joint injuries (such as a meniscal tear or knee osteoarthritis).

Hamstring Tendonitis
Tissue damage and inflammation to one or more hamstring tendon at its attachment to the inner or outer aspect of the back of the knee resulting in pain at the back of the knee. Usually an overuse injury resulting from repetitive acceleration and deceleration activities. Pain is usually experienced on firmly touching the affected hamstring tendon. Pain may also increase when performing a hamstring curl or when stretching the hamstring muscle.

Referred Pain
Pain referred to the knee from another source such as the lower back or hip joint, often associated with symptoms above or below the knee (such as lower back pain or stiffness or pain in the hip, buttock, groin, thigh, lower leg, ankle or foot). Typically associated with pain on firmly touching the region responsible for the referred pain or loss of movement in that region. Sometimes in association with pins and needles or numbness in the affected leg or foot.

Less Common Injuries

Osgood Schlatters Disease

A condition affecting adolescents during a period of rapid growth resulting in inflammation of the growth plate located at the top of the shin bone (tibia) where the patella tendon attaches to shin bone just beneath the knee cap. Occurs in association with high activity levels such as running, jumping, squatting or climbing stairs. There is usually an increased bone prominence at the top of the tibia (beneath the knee cap) that is sore to firmly touch. Pain may also increase during activities such as squatting, running, jumping, kneeling and climbing stairs.

Sinding Larsen Johanssen Disease

A condition affecting adolescents during a period of rapid growth, resulting in inflammation of the growth plate located at the bottom of the knee cap. Occurs in association with high activity levels such as running, jumping, squatting or climbing stairs. There is often an increased bone prominence at the bottom of the patella that is sore to firmly touch. Pain may also increase during activities such as squatting, running, jumping, kneeling and climbing stairs.

Pre-Patellar Bursitis
Inflammation of the fluid filled sac (known as a bursa) located directly on top of the knee cap (pre-patellar bursa) typically as a result of excessive kneeling on hard surfaces. Associated with significant swelling at the front of the knee and often pain on firmly touching the pre-patellar bursa.

Quadriceps Tendonitis
A condition characterised by tissue damage and inflammation to the quadriceps tendon at its attachment to the top of the knee cap resulting in pain at the front of the knee. Usually an overuse injury resulting from repetitive running, jumping, squatting or kicking activities. Pain is usually experienced on firmly touching the quadriceps tendon at its attachment to the top of the knee cap. Pain may also increase when performing a deep squat or when stretching the quadriceps muscle.

Stress Fracture of the Patella
Stress fracture of the knee cap, usually due to a recent increase in activity such as jumping or running; associated with localised tenderness on firmly touching the affected region of the bone.

Perthes’ Disease
Damage to the bone and cartilage of the head of the thigh bone located in the hip joint. Occurs in children, usually between the ages of 4 and 10. Results in a limp or a dull ache in the thigh, groin or knee. Typically associated with reduced hip range of movement.

Slipped Capital Femoral Epiphysis
Disruption of the growth plate of the upper thigh bone at the hip joint. Usually occurs in older children (particularly between 12 and 15 years) either suddenly or, more commonly, gradually over time. The most common presentation is a limp. Often the only pain that is felt may be in the knee. Typically associated with reduced hip range of movement.