Overview
The patella tendon / ligament joins the kneecap (patella) to the shin bone or tibia. This tendon is extremely strong and allows the quadriceps muscle group to straighten the leg. The quadriceps actively straighten the knee in jumping to propel the individual off the ground as well as functioning in stabilizing their landing. As such this tendon comes under a large amount of stress especially in individuals who actively put extra strain on the knee joint such as those who regularly perform sports that involve direction changing and jumping movements. With repeated strain, micro-tears as well as collagen degeneration may occur as a result in the tendon. This is known and patellar tendinopathy or “jumpers knee.”
Causes
Activities/sports that involved direction changing and jumping movements
Symptoms
Pain at the bottom and front of the kneecap especially pressing or palpating
Aching and stiffness after exertion
Pain when contracting the quadriceps muscles
Affected tendon may appear larger than the unaffected side
Calf weakness
Diagnosis
Physical examination
MRI
Treatment
Rest
Training adaption
Cold therapy
Knee support
Sports massage
Eccentric strengthening
Anti-inflammatory medications
Ultrasound or laser therapy
Physical therapy
Surgery
Source: http://www.sportsinjuryclinic.net/sport-injuries/knee-pain/jumpers-knee