Jumper’s Knee

Patellar tendinitis (tendinopathy), also known as jumper’s knee, is a common overuse injury of the patellar tendon. It is usually due to repetitive microtrauma of the connective tissue due to high-volume jumping, running and changing directions. It is most common among those who participate in jumping sports such as basketball, volleyball and gymnastics but has been seen among exercise enthusiasts due to poor lower limb biomechanics. Often, the site of disruption is at the inferior pole of the patella. Sufferers commonly experience a gradual onset of anterior knee pain during any jumping or acceleration-deceleration activities performed while training. This pain can be localized to the bottom portion of the patella or diffuse throughout the majority of the kneecap. In more severe cases, sufferers may complain of progressive discomfort during other activities that stretch the tendon such as sitting in a chair or stair climbing. This level of discomfort more often occurs when the tendon slightly thickens or is partially torn.

Aside from aggravating activities, risk factors such as older age, acute high volume exposure to unaccustomed stress, playing sports (basketball) on hard surfaces, decreased ankle mobility in dorsiflexion, incorrect landing mechanics (e.g., tibial translation), anthropometric variables such as taller height, and weakness or tightness within the musculature surrounding the knee (e.g., quadriceps, calves, and gluteals) can all have a part to play in the progression of patellar tendinitis. Diagnosis and treatment guidelines should be implemented by a physician or physical therapist and are often symptom specific. An exercise professional can have a part to play in some of the recovery process while following set guidelines defined by an appropriate medical professional.

Unfortunately, the full process of rehab and recovery can be relatively long for jumper’s knee; lasting up to a year among those prone to the issue. Ceasing the actions that caused the problem is step one. Rehab places a major focus on unloading the patellar tendon during daily movements, sport movements, or training activities - as well as correcting deleterious biomechanics. As with other overuse injuries, relative rest is critical to recovery; however, absolute rest can result in a weakened condition. Range of motion exercises should emphasize flexibility in ankle dorsiflexion (plantarflexors) as well as in the hamstrings, quadriceps and calves. This will improve landing mechanics and stability at the knee when impact forces are applied. Eccentric strengthening exercises also are vital to improve the resilience of the patellar tendon to future stress. Exercises such as a quarter squat performed on a decline board (as though the client is on a downhill slope) may be used. Decline stepping activities down a set of stadium stairs or otherwise may provide similar benefits.

Biomechanics at the hips, knees, and ankles will usually be analyzed by the physician or physical therapist to identify opportunities for patellar tendon unloading. In particular, ankle and calf movements can absorb significant amounts of force that would otherwise be transmitted to the knees. Back squatting is often an agitator and forward rebound lunges should be avoided. Additionally, it is important to direct energy during stepping into the heel to reduce cross-knee loading. Stepping through the heel with increased hip activity will redistribute weight and tension favorably for the patellar tendon. These modifications should be applied by the exercise professional during sessions as the client continues to heal.

Physical therapy may be mildly painful for the client, but a pain-free status is required before full healing can be declared. Unfortunately, no therapeutic modalities show compelling evidence for helping the recovery process of patellar tendinitis. Massage and self-myofascial release techniques, which the exercise professional may be qualified to implement, have not been found to be effective. Essentially, sufferers must slowly progress back to full function using the activities described previously as well as exercises that promote muscle balance at the knee for optimal patellar tracking. This requires maintaining balance between the vastus medialis and vastus lateralis. Gluteal activation and general hip extensor and knee flexor work can also be effective for reducing knee stress. Integrating any high-impact activities or plyometrics should be carefully monitored - after being permitted by the physical therapist. Some clients may find use in wearing a prophylactic device or stabilizing sleeve to promote optimal temperature, stability and blood flow to the region as training activities begin to increase in intensity again.

The following activities may help improve mobility and strength balance in the region surrounding the patellar tendon. Again, focusing on unloading the tendon through biomechanical modifications can go a long way in expediting recovery while still engaging in somewhat regular levels of activity.

Decline Quarter Squat	Short-height Hamstring Step-ups
Gluteal Bridge	Shallow Pistol Squat (TKE)
Hamstring and Calf Stretch	Quadriceps Stretch