Patellar Tendonitis Or “Jumper’s Knee”

Patellar tendonitis, or jumper’s knee, occurs due to small tears in the patellar tendon. It is commonly seen in individuals who frequently jump – hence the name – but can also occur in running sports or sports that require rapid changes of direction.

Jumper’s knee is a condition that is frequently observed in the athlete population, but has a very good prognosis provided it is diagnosed and treated correctly. This post covers the symptoms, diagnostic tests, and treatment options for patellar tendonitis.

What Is Jumper’s Knee?

Jumper’s knee is an overuse injury of the knee extensor muscles in the knee. It occurs in people who perform repetitive activities where there is jumping, landing, acceleration, and sudden deceleration. Microtears can appear in the patellar tendon after these repetitive movements, particularly when there is insufficient time to rest between these activities.

These microtears are mostly seen at the inferior (lower) pole of the patella where patella tendon inserts into the patella bone (your kneecap). At first, there is just swelling and edema (fluid) in the tendon fibers.

However, if the activity continues, then the degenerative changes in the tendon can become irreversible until it finally thickens into an irregular fibrous envelope. The term ‘tendonitis’ is a misnomer because inflammatory cells are mostly absent in this condition – the term tendinopathy (disorder of the tendon) is more commonly used nowadays.

Jumper’s Knee Classification

Jumper’s knee is classified using the Blazina classification system, where symptoms are subdivided based on the onset in relation to physical activity. This classification divides jumper’s knee into four stages, namely:

Pain after a sports activity
Pain at the beginning of sports activity that disappears with a warm-up and sometimes may reappear with fatigue
Pain at rest and during a sports activity with simultaneous deterioration of performance
Rupture of the tendon

Another method used to classify jumper’s knee is based on the duration of symptoms:

Acute: when symptoms are present between 0 to 6 weeks
Sub-acute: when symptoms are present between 6 to 12 weeks
Chronic: after over 3 months of symptoms

Symptoms Of Patellar Tendonitis

Knee Pain

Knee pain can be caused by many factors. Overuse injuries, direct trauma to the knee and arthritis are the most common causes of knee pain. Damage to the knee structures may cause swelling, scar tissue formation (fibrosis), and loss of function of the joint. Pain is often accompanied by difficulty walking, weakness, and instability. When the knee is overused, the thigh and shin bones (femur and tibia), cartilage, or tendons may experience stress. This leads to pain and discomfort as well as stiffness in the knee. Overuse injuries are common among athletes who participate in sports that involve running, jumping…

Reduced Range of Motion in Knees

A knee can feel stiff if there is some swelling in or around the joint or muscle tightness can caused restricted motion This can occur from a problem in the knee joint, such as inflammation, arthritis, or infection, or an injury. The distance and direction that a joint may move are referred to as its range of motion. Various joints in the human body have specific normal ranges set by doctors and therpists. One study, for example, found that a normal knee should be able to bend to between 133 and 153 degrees. A typical knee should also be able to extend fully straight. Limitation of motion occurs when a person range of motion in any limb is reduced below the normal range….

Here are some classic signs and symptoms of patellar tendonitis:

Pain And Tenderness In The Patellar Tendon

The location of the pain and tenderness is very specific for patellar tendonitis. Jumper’s knee usually presents with well-localized pain and tenderness at the inferior pole of the patella, front of the knee below the kneecap. Pain in other parts of the tendon may be associated with other conditions like runner’s knee.

Localized Swelling

There may be localized swelling over the patellar tendon, with tenderness on palpation. This is a diagnostic sign in the absence of other movement restrictions in the knee.

Pain With Movement

Pain in the patella tendon is commonly worse with activities such as prolonged sitting, squatting, and climbing stairs. People with jumper’s knee may also experience knee pain with prolonged flexion, known as the “movie theater sign,” as this is the common position when sitting to watch a movie.

Patella tendon pain is usually very acute and sharp when there is an activity that suddenly loads the knee, such as jumping or running. Conversely, the pain often settles with rest or when the load is removed from the knee.

Common Causes Of Patellar Tendonitis

Here is a list of the most common ways that someone may develop jumper’s knee:

Tendon Tear

An injury to the patellar tendon during a sudden acceleration or deceleration movement can cause a tear to the patellar tendon which affects the ability to extend the knee. The tear can start as microtears which cause jumper’s knee, but might ultimately progress to a partial or complete tear. Tears to the patellar tendon commonly occur during accelerated abrupt movements, such as in sports or in an accident which results in injury to the knee.

Repetitive Jumping

Athletes in sports that require frequent and repetitive jumping, such as volleyball, basketball, and long and high jumps, especially on hard surfaces, may begin to experience patellar tendonitis.

Repetitive high power movements can cause microtears in the patellar tendon. These microtears may lead to degeneration of the tendon over time, which can result in patellar tendonitis.

Overuse

Overuse of the knee, where the knee has to constantly support greater loads than it can handle, can lead to jumper’s knee. This can occur over a short period, or gradually over an extended period of time. Factors that contribute to this include deconditioning, inadequate rest between exercise sessions, and a higher BMI.

Other factors that can lead to overuse of the patellar tendon include a higher waist-to-hip ratio, a leg-length difference of more than 20 mm, a lower foot arch height, weaker quadriceps, and poorer vertical jump performance as required in certain professions like football, dancing, and gymnastics.

All of these factors contribute to the likelihood of developing jumper’s knee as they may increase the load through the leg, causing the patellar tendon to overcompensate.

Common Treatments For Patellar Tendonitis

Below is a list of treatment options for patellar tendonitis:

Rest

The first method to treat patellar tendonitis is to rest the knee and the patellar tendon. By allowing time for the knee to adequately rest, the patella tendon can have time to rejuvenate and heal.

However, it’s important to note that prolonged periods of sitting is not the same as rest. In fact, prolonged sitting may worsen the pain and symptoms of jumper’s knee. Rather, rest should include deloading the knee by avoiding painful positions or activities, such as stairs or sport. When it is necessary to sit, you can rest with your leg extended over a stool or chair.

Elevating Your Knee

Elevating the knee helps reduce the swelling of the patellar tendon by reducing unwanted blood flow to the joint. This will reduce the edema, redness, and the pain in the lower part of the patella.

Ice Packs

Ice packs and cold therapy will constrict the blood vessels and decrease unwanted blood flow to the area, thereby reducing swelling and pain. You can use cold therapy intermittently every 15-20 minutes as needed for this.

Taping And Bracing Of The Knee

You can use kinesiology tape to help support the knee. If you have never done this before, you can ask your doctor or physical therapist to help you tape the knee for support. The KT tape increases muscle tension and keeps them in a state of contraction. It can also decrease the pain and improve inflammation by increasing circulation.

You can also use knee support bands and caps, infrapatellar straps, or braces to support the knee (1). These knee support devices limit excessive patella tendon strain at the site of the jumper’s knee.

They also help by increasing the patella-to-patellar tendon angle and decreasing the patellar tendon length, thereby reducing any excessive tendon stretch which could worsen the symptoms of jumper’s knee.

Stretching And Strengthening

Stretching and strengthening exercises under the supervision of a physical therapist can help to both treat and prevent jumper’s knee. Targeted exercises can strengthen the quadriceps and other muscles that support the knee to help distribute the load equally across the knee joint.

Common exercises a physical therapy may prescribe for jumper’s knee may include a hamstring stretch, calf stretch, kneeling hip flexor stretch, wall slides, and straight leg raises. Physical therapy is often used in conjunction with other treatments to rehabilitate the knee, such as over-the-counter or prescription medication.

Regenexx – Ortho-Biologic Options

Often the conservative treatments above fail and patients continue to suffer through pain. For many years the only other option was corticosteroid injections or surgery.

Corticosteroids can help temporarily but long term runs the risk of further injuring the tendon which can lead to tendon ruptures (4)! Orthobiologics have bridged the gap in orthopedic care over the past 15-20 years.

PRP (platelet rich plasma) is a good option for mild to moderate cases. The growth factors found in platelets help stimulate tendon repair by stimulating local repair cells to aid in healing.

BMC (bone marrow concentrate) is a good option where the damage to the tendon is more severe. Dr. Centeno discussed this back in 2019 when he highlighted the results of his brother’s damaged and torn patella tendon.

The body’s repair cells are concentrated from bone marrow aspirate, processed, and re-introduced via ultrasound guidance into the affected tendon along. These injected cells stimulate repair of the microtears in the patella tendon and help it to recover. Tendon repair with Regenexx has been shown to be very successful (2).

Together these treatments have reduced the need for more invasive surgical treatments.

Surgery For Jumper’s Knee

Surgical treatment for jumper’s knee is a last resort, reserved only for individuals where conservative treatment has failed, or when the symptoms are severe and the tendon tear has progressed.

During a patella tendon surgery, called open debridement, the patellar tendon is debrided by removing the disorganized fibrous tissue and degenerative areas. The tendon is reattached with sutures or anchors.

Increasingly, tissue debridement and release is completed through on open incision in the front of the knee overlying the tendon. One reason to exhaust all options prior to having surgery on your patella tendon, surgical success rate can be as low as 50% (5).

While success may be a coin flip, the other side of that coin in some cases means you are worse than where you started!

Physical Therapy for Patellar Tendonitis

Patellar tendonitis, often referred to as jumper’s knee, is a common ailment among athletes and active individuals. This condition can significantly impact one’s mobility and quality of life. Fortunately, physical therapy offers a beacon of hope, providing effective strategies for managing and overcoming this challenge. In this comprehensive guide, we delve into the world of physical therapy for patellar tendonitis, offering insights and actionable advice to help you bounce back stronger.

Prolotherapy Injections

It has been successful in the treatment of many disorders including neck, shoulder, knee, and ankle pain. Dr. Centeno recently published an article in The Journal of Prolotherapy in which he discusses the use of x-ray guidance with prolotherapy. This ensures that the injection is in the correct place to maximize clinical results. Dr. Centeno discusses the use of prolotherapy for the treatment of neck, knee, sacroiliac joint, ankle, ischial tuberosity, and shoulder pain. At the Centeno-Schultz Clinic x-ray guided prolotherapy is just one of the therapies utilized in the successful treatment of pain. Regenerative injection therapy (RIT) or prolotherapy…

PRP for Patellar Tendinopathy

The prepared PRP is then ready for injection or application to the target area. This may involve the use of ultrasound or other guidance techniques to ensure precise delivery of PRP to the injured or affected tissue. The resulting PRP is rich in platelets, which contain a high concentration of growth factors and bioactive proteins that are thought to promote tissue healing and regeneration. These growth factors, such as platelet-derived growth factor (PDGF), transforming growth factor-beta (TGF-β), and vascular endothelial growth factor (VEGF), play a key role in the regenerative properties of PRP.

PRP Injections

PRP is short for platelet-rich plasma, and it is autologous blood with concentrations of platelets above baseline values. The potential benefit of platelet-rich plasma has received considerable interest due to the appeal of a simple, safe, and minimally invasive method of applying growth factors. PRP treatments are a form of regenerative medicine that utilizes the blood healing factors to help the body repair itself by means of injecting PRP into the damaged tissue. In regenerative orthopedics, it is typically used for the treatment of muscle strains, tears, ligament and tendon tears, minor arthritis, and joint instability. There have been more than 30 randomized controlled trials of PRP…

PRP Knee Injections

PRP stands for Platelet-Rich Plasma. Platelets are blood cells that prevent bleeding. They contain important growth factors that aid in healing. Plasma is the light yellow liquid portion of our blood. So PRP is simply a concentration of a patient’s own platelets that are suspended in plasma and are used to accelerate healing. PRP is NOT stem cell therapy. Regrettably, blood contains few circulating stem cells. Rich sources of stem cells are bone marrow and fat. PRP is rich in growth factors. There are many different types of growth factors with different properties. VEGF is a very important one as it can increase the blood flow to an area.

Tenex Procedure

The Tenex Health TX® System is a minimally-invasive, percutaneous procedure using ultrasonic energy to treat pain-generating soft and hard tissue conditions. This treatment is clinically proven to remove tendon pain for over 85% of patients1,2,3,4,5. If conservative approaches such as physical therapy, cortisone injections, medication, and downtime do not provide relief, Tenex may be your next option.Using this technique, we help patients restore musculoskeletal function, may provide quick pain relief, and avoid invasive surgery and dangerous drugs. Tenex may also be effective if you have had a failed surgical procedure. Your doctor will use image-guidance to identify and target the…

Who Is At Risk Of Jumper’s Knee?

Certain individuals are at greater risk for jumper’s knee due to their occupation or other pre-existing conditions. Studies have shown that jumper’s knee is very common in elite athletes due to overuse of the patellar tendon (3). For example, athletes who play volleyball, basketball, or compete in the long and high jump have a higher incidence of jumper’s knee.

Other risk factors include:

igament laxity,
tightness of the quadriceps and hamstring muscles,
excessive Q-angle of the knee,
abnormal patellar height,
a history of ongoing knee inflammation or injury,
excessive force or loading of the knee,
excessive volume and frequency of training,
ground hardness,
body mass index,
leg-length difference,
the arch height of the foot, and
quadriceps strength.

How Is Patellar Tendonitis Diagnosed?

Jumper’s knee or patella tendonitis is diagnosed by the following methods:

Physical Examination Of The Knee

A doctor will start by thoroughly examining the entire lower extremity to look for muscular or functional deficits at the hip, knee, and ankle. This is because a misaligned foot or heel can put excess strain on the knee extensor tendons.

A doctor will also examine the patella closely to check for swelling over the patellar tendon. In the jumper’s knee, the patellar tendon is tender to palpate. Other obvious signs of a jumper’s knee are Basset’s sign and the “passive extension-flexion” sign. These signs are considered positive when there is reduced tenderness to palpation in the flexed knee position.

Another diagnostic test during examination is the “standing active quadriceps sign.” The sign is considered positive when there is reduced tenderness to palpation as the quadriceps muscle contracts.

Apart from the physical exam, there are multiple scales to evaluate tendon overuse. An example is the Victorian Institute of Sport Assessment (VISA) score which evaluates symptoms and functionality in patellar tendinopathy.

Diagnostic Tests

There is no gold standard imaging test for jumper’s knee. Instead, a variety of tests are used to examine the knee and rule in or rule out certain factors.

In cases where injury to the bone is suspected, a doctor may request an x-ray. Although there are radiographic changes in the tendon, such as elongation of the involved pole of the patella, calcification, and increased density within the patellar tendon matrix, these changes are usually only seen within six months of the onset of symptoms.

Ultrasound is emerging as the leading imaging test for jumper’s knee. It is also non-invasive, can be repeated multiple times, and yields a dynamic image of the knee. During our examination, it is standard to utilize a diagnostic ultrasound to better evaluate the tendon.

Teauty of ultrasound is that we can see in real time, while you are in the office, what it looks like. And based off that we can better educate on plan moving forward and treatment options.

Pictures below show normal tendon on the left compared to patella tendinopathy on the right.

In cases of chronic jumper’s knee, an MRI scan is helpful to see if the tendon is thickened or affected in any way. Both ultrasound and MRI can detect abnormalities in the patellar tendon and indicate the severity of the condition.

Recovery And Follow-Up

Most cases of jumper’s knee resolve without surgical management. However, symptom resolution and return to sport can be very slow.

Recovery depends on the severity of pain, the grade of dysfunction, the athlete’s sport, the quality of rehabilitation, and the athlete’s performance level.

In cases of mild tendinopathy, the patient can return to sport in as little as 20 days, however in severe cases this could take 90 days or more. Those with severe dysfunction may require six to 12 months to recover. Patients who require surgery usually take about four months to recover. The surgery requires the knee to be immobilized in full extension for two weeks.

After that, a progressive range of rehabilitation exercises can begin. Full weight-bearing as tolerated may begin from day one, depending on the orders from the surgeon.

Jumper’s Knee Has A Good Prognosis

The prognosis of jumper’s knee is excellent as most patients will recover without surgery. However, the recovery process does take time and requires input from healthcare professionals.

At Centeno-Schultz Clinic (CSC), our clinicians, orthopedic specialists and physical therapists will help you get the best results. They will assess and monitor you closely, tailoring the therapy based on your progress and future goals. If you have a jumper’s knee, schedule a visit with one of our board-certified, fellowship-trained doctors today.

Christopher J. Centeno, MD

Christopher J. Centeno, M.D. is an international expert and specialist in Interventional Orthopedics and the clinical use of bone marrow concentrate in orthopedics. He is board-certified in physical medicine and rehabilitation with a subspecialty of pain medicine through The American Board of Physical Medicine and Rehabilitation. Dr. Centeno is one of the few physicians in the world with extensive experience in the culture expansion of and clinical use of adult bone marrow concentrate to treat orthopedic injuries. His clinic incorporates a variety of revolutionary pain management techniques to bring its broad patient base relief and results. Dr. Centeno treats patients from all over the US who…

John Schultz, MD

John R. Schultz M.D. is a national expert and specialist in Interventional Orthopedics and the clinical use of bone marrow concentrate for orthopedic injuries. He is board certified in Anesthesiology and Pain Medicine and underwent fellowship training in both. Dr. Schultz has extensive experience with same day as well as culture expanded bone marrow concentrate and sees patients at the CSC Broomfield, Colorado Clinic, as well the Regenexx Clinic in Grand Cayman. Dr. Schultz emphasis is on the evaluation and treatment of thoracic and cervical disc, facet, nerve, and ligament injuries including the non-surgical treatment of Craniocervical instability (CCI). Dr. Schultz trained at George Washington School of…

John Pitts, M.D.

Dr. Pitts is originally from Chicago, IL but is a medical graduate of Vanderbilt School of Medicine in Nashville, TN. After Vanderbilt, he completed a residency in Physical Medicine and Rehabilitation (PM&R) at Emory University in Atlanta, GA. The focus of PM&R is the restoration of function and quality of life. In residency, he gained much experience in musculoskeletal medicine, rehabilitation, spine, and sports medicine along with some regenerative medicine. He also gained significant experience in fluoroscopically guided spinal procedures and peripheral injections. However, Dr. Pitts wanted to broaden his skills and treatment options beyond the current typical standards of care.

Jason Markle, D.O.

Post-residency, Dr. Markle was selected to the Interventional Orthopedic Fellowship program at the Centeno-Schultz Clinic. During his fellowship, he gained significant experience in the new field of Interventional Orthopedics and regenerative medicine, honing his skills in advanced injection techniques into the spine and joints treating patients with autologous, bone marrow concentrate and platelet solutions. Dr. Markle then accepted a full-time attending physician position at the Centeno-Schultz Clinic, where he both treats patients and trains Interventional Orthopedics fellows. Dr. Markle is an active member of the Interventional Orthopedic Foundation and serves as a course instructor, where he trains physicians from around the world.

Brandon T. Money, D.O., M.S.

Dr. Money is an Indiana native who now proudly calls Colorado home. He attended medical school at Kansas City University and then returned to Indiana to complete a Physical Medicine and Rehabilitation residency program at Indiana University, where he was trained on non-surgical methods to improve health and function as well as rehabilitative care following trauma, stroke, spinal cord injury, brain injury, etc. Dr. Money has been following the ideology behind Centeno-Schultz Clinic and Regenexx since he was in medical school, as he believed there had to be a better way to care for patients than the status quo. The human body has incredible healing capabilities…

References

1. Lavagnino M, Arnoczky SP, Dodds J, Elvin N. Infrapatellar Straps Decrease Patellar Tendon Strain at the Site of the Jumper’s Knee Lesion: A Computational Analysis Based on Radiographic Measurements. Sports Health. 2011;3(3):296-302. doi:10.1177/1941738111403108

2. Docheva D, Müller SA, Majewski M, Evans CH. Biologics for tendon repair. Adv Drug Deliv Rev. 2015;84:222-239. doi:10.1016/j.addr.2014.11.015

3. Rudavsky A, Cook J. Physiotherapy management of patellar tendinopathy (jumper’s knee). J Physiother. 2014 Sep;60(3):122-9.

4. Lu H, Yang H, Shen H, Ye G, Lin XJ. The clinical effect of tendon repair for tendon spontaneous rupture after corticosteroid injection in hands: A retrospective observational study. Medicine (Baltimore). 2016 Oct;95(41)

5. Haber DB, Ruzbarsky JJ, Arner JW, Vidal AF. Revision Patellar Tendon Repair With Anchors, Allograft Augmentation, and Suspensory Fixation. Arthrosc Tech. 2020 Oct 24;9(11):