Chronic Jumper’s Knee
What is Chronic Jumper’s Knee?
Chronic jumper’s knee is the common term used to describe patellar tendinosis. It generally occurs when a patellar tendonitis has persisted for more than around 6 weeks, when it is then referred to as ‘chronic’ and sometimes alternatively called chronic patellar tendinopathy. Chronic jumper’s knee is characterized by degenerative changes in the patellar tendon. This is the tendon that connects the kneecap (patella) to the shin bone (tibia) in the leg. The patellar tendon’s role is to work with the muscle in the front of the thigh, the quadriceps, allowing you to extend the knee when you kick, run and jump. Chronic jumper’s knee weakens the tendon causing long-term pain.
What causes Chronic Jumper’s Knee?
Chronic jumper’s knee is an overuse injury that is caused by repeated stress on the patellar tendon. Athletes who participate in sports that demand repetitive and explosive jumping, kicking and landing actions, such as volleyball, basketball, dancing and soccer are commonly diagnosed with jumper’s knee, although the condition can also occur with other physical activities, such as running or even weightlifting too.
When the patellar tendon is subjected to the intense forces of jumping and landing over and over again, the stress results in tiny tears in the tendon. The body attempts to repair these tiny tears through natural inflammatory processes. Acute (short-term) patellar tendonitis, or jumper’s knee, often occurs following an injury and involves an active inflammatory process by the body. If treated correctly, recovery time is generally 3-6 weeks. However, if it is left untreated and the affected leg continues to be used, as the tears multiply, they cause intense pain from inflammation and weakening of the tendon. Over the period of weeks and sometimes months, chronic jumper’s knee develops, where degenerative changes occur in the tendon. Some of these changes include the development of abnormal blood vessels, and at the cellular level include the absence of inflammatory cells in the tendon, poor healing, and disorganization and poor quality of the collagen fibres, which often present as decreased tensile strength.
It is commonly accepted that many factors can contribute to the development of chronic jumper’s knee. These include intrinsic factors (those that are pertaining to the person or athlete themselves) such as strength imbalances, postural alignment, structure of the feet and flexibility. However extrinsic (outside) factors such as the physical load on the leg, repetition, intensity, frequency and duration of exercise are thought to be the primary cause contributing to this overuse syndrome.
When it occurs in older people, chronic jumper’s knee is usually a result of degeneration that happens due to repetitive micro-damage over time, or sometimes an acute injury to the tendon that hasn’t allowed adequate healing. These types of traumatic patellar tendinopathy are, however, much less common than overuse injury.
What are the symptoms of Chronic Jumper’s Knee?
Whilst every patient experiences symptoms differently, some of the most common symptoms of chronic jumper’s knee are:
- Tenderness and pain around the patellar tendon area
- Pain when jumping, running, or walking
- Pain with bending or straightening the knee
- Tenderness felt behind the lower part of the kneecap
- The knee often feels incredibly stiff first thing in the morning.
For the syndrome to be chronic, these symptoms will have been present for at least 6 weeks.
Initially the pain may be felt at the beginning of physical activity or after an intense workout. If the condition is left untreated, the pain usually worsens and inhibits the patient from playing their sport. As the condition progresses to become chronic jumper’s knee, daily routine activities such as climbing stairs or getting on and off a chair may start to become a problem.
Some of the symptoms experienced with chronic jumper’s knee may resemble those seen with other conditions too, so it is always best to speak to your sports podiatrist for a correct diagnosis.
How is Chronic Jumper’s Knee Diagnosed?
Chronic jumper’s knee, or patellar tendinopathy, is generally suspected when a patient has had symptoms that have lasted for more than 6 weeks. Your sports podiatrist will make enquiries about your past health, your symptoms and your exercise program. They will conduct a thorough physical examination to confirm the diagnosis. For patients with severe symptoms or if there is no improvement with early conservative treatment, an MRI or ultrasound may be recommended so that the structures inside the knee can be visualized at great detail, and a treatment and rehabilitation plan can be devised.
Treatment options for Chronic Jumper’s Knee
You can begin your treatment for chronic jumper’s knee at home, simply by resting the affected leg. RICE (rest, ice, compression, elevation) can be used if there is swelling.
Once you have consulted with your sports podiatrist and confirmed your diagnosis and extent of the injury, they will be able to recommend a treatment protocol for your individual condition. Treatment for chronic jumper’s knee usually follows one of three approaches: conservative, injection-based, or surgical.
Conservative treatments are non-invasive. Some examples include: -Bracing, which can be used to relieve pain without restricting movement.
-Eccentric exercise has been an essential component of conservative therapy for chronic jumper’s knee for many years, and there is a substantial amount of clinical evidence to support the efficacy of this approach. Your podiatrist will be able to recommend whether this is an appropriate approach to therapy for your condition, and if so, they will guide you through particular controlled exercises that are safe and beneficial. A main goal of exercise for treatment and rehabilitation for chronic jumper’s knee, is to strengthen the quadriceps and stretch the hamstrings.
-Extracorporeal Shockwave Therapy (EST) delivers a targeted pressure sound wave into the affected tendon. The pressure breaks down scar tissue and causes micro-trauma, signalling the brain to direct healing processes to the area. Shock wave therapy also stimulates the release of pain-relieving substances into the blood.
- Injection-based treatment:
There are a variety of injection therapies that are used in the treatment of chronic jumper’s knee. These include dry needling, platelet-rich- plasma, autologous blood, corticosteroids, hyperosmolar dextrose, and sclerosing substances. These injections aim to promote a healing response within the tendon, with the exception of sclerosing substances, which aim to destroy the abnormal blood vessels that are often present with chronic jumper’s knee.
- Surgical treatment:
Surgery is often a last resort for the treatment of chronic jumper’s knee, when all other treatment options have been exhausted, or in severe cases. Surgery is most commonly arthroscopic, and aims to debride and resection the patellar pole.
Recovering from Chronic Jumper’s Knee
The time it takes to recover from chronic jumper’s knee largely depends on the extent of the injury and the condition of the tendon when the treatment protocol is commenced. It is reasonable to expect that it will take at least a few months, but up to 6-8 or more months to fully recover, depending on the individual circumstances. Your sports podiatrist can discuss expected recovery time with you during your consultation.
Chronic Jumper’s Knee prevention
To reduce your risk of developing chronic jumper’s knee, you can take the following steps:
- Work on strengthening and stretching your muscles: strong thigh muscles (quadriceps) and flexible hamstrings (back of the leg) will help the patellar tendon to better-handle the stresses that cause chronic jumper’s knee.
- Improve your exercise technique: undertaking correct exercise technique is always beneficial in injury prevention. Consider taking lessons or professional instruction, especially when starting a new sport or exercise equipment.
- Don’t continue to exercise through pain: as soon as you notice any exercise-related knee pain, stop exercising and rest. Address the pain by seeing your doctor or podiatrist, who will be able to conduct an assessment and make recommendations for your recovery and safe return to exercise.
Please note that the information contained in this article should not be taken as general advice. If you think you have chronic jumpers knee then you should consult with a suitably qualified sports podiatrist. Appointments can be made online www.sydneypodiatrist.net.au or by calling 93883322.
Karl Lockett – sports podiatrist.