Patellar Tendonitis

Patellar tendonitis is an injury of the tendon that connects your kneecap – the patella – to your shinbone.

You use the patellar tendon every time you extend your leg, like when you’re kicking, running, or jumping, which is why patellar tendonitis is most common in jumping sports such as volleyball or basketball. However, it can occur in non-athletes as well.

Getting rid of patellar tendonitis can take anywhere between less than 3 months1 and up to 15 years2. The key to a fast recovery is doing the right things early on and avoiding certain treatment mistakes that cause setbacks. This page will tell you everything you need to know.

Symptoms

In patellar tendonitis the pain will only be on the front of the knee. You will feel it directly in the patellar tendon, either right below the kneecap or where the patellar tendon attaches to the shinbone.

The pain will get worse with activities such as running, jumping, squatting, kneeling, or sitting, and although the pain response is usually immediate, it can also take up to 48 hours to set in.

Squatting, running, and jumping can worsen patellar tendonitis.
Squatting, running, and jumping can worsen the symptoms.

In the early stages of patellar tendonitis you will only get pain after intense exercise or sports, but as the injury progresses you may begin to feel it during sports and later on even while at rest. The sooner you start rehab, the shorter your recovery will be.

You need to see a doctor immediately if you have one of the following symptoms:

  • Your knee is swollen or red
  • Your pain is getting worse or is very sharp
  • Your pain prevents you from doing everyday activities
  • You have a locking sensation in your knee
  • Your knee feels unstable

Causes

The most common cause of patellar tendonitis is repeated overuse of the tendon over a longer period of time. Usually this overuse is a combination of training too hard and training too frequently.

Repeated overuse interrupts the tendon’s attempts to grow stronger in response to the training loads and as this continues, cellular changes inside the tendon begin to occur3. Unless the overuse is stopped, the tendon will slowly begin to grow weaker, which in turn makes future overuse more likely.

That’s why training through the pain can add months to your recovery time.

Contrary to popular belief tendonitis is NOT caused by inflammation4. Inflammation does play a minor role in the injury5, but tendonitis is not an inflammatory response per se, which is why suppressing inflammation through anti-inflammatories will actually be detrimental in most situations (see section on treatment below).

A less frequent cause of patellar tendonitis is direct trauma to the tendon6, like suffering a fall or getting hit in the knee.

Risk Factors

Risk factors for patellar tendonitis include:

  • High training volume7 (e.g., 8.94-times normal risk for more than 20 hours of weekly training time8)
  • Big increases in training load and or training volume9
  • Having a higher vertical leap10
  • Muscular problems such as tight hamstrings, calves, or quadriceps muscles11
  • Improper jumping mechanics12
  • Training on hard surfaces13
  • Participation in jumping sports14, especially volleyball15 or basketball16
  • No gradual return to sports after a rest period of 6+ weeks17
  • Diabetes18
  • Older age (odds ratio of 4.209)19
  • Abnormal estrogen levels20
  • Central adiposity for men and peripheral adiposity for women21
  • Autoimmune or connective tissue diseases (e.g., psoriatic arthritis)22

 

Frequenly Asked Questions

How do you treat patellar tendonitis?

According to academic research the most effective treatment for patellar tendonitis is doing slow strengthening exercises for the patellar tendon. In contrast, passive treatments like PRP-injections or shockwave therapy are not supported by strong evidence.

How long does it take for tendonitis in the knee to heal?

It can take anywhere between less than 3 months and up to 15 years. The key to a fast recovery is doing the right things early on and avoiding certain treatment mistakes that cause setbacks.

What is the fastest way to heal patellar tendonitis?

The fastest way to heal patellar tendonitis is to start rehab as soon as the diagnosis was made by working with someone with expert knowledge about the injury. Unfortunately, most people ignore the pain and train through it, which makes recovery take longer.

Does patellar tendonitis ever go away?

With the right approach, every tendon can get stronger. It’s merely a question of finding a strengthening exercise that works for you and then doing it consistently over a longer period of time. With this approach people have gotten better even after years of pain.

Can you walk with patellar tendonitis?

In almost all cases walking is safe for someone with this injury.

Will a knee brace help patellar tendonitis?

A knee brace can reduce pain temporarily, but it will not lead to long-term improvement. To make a tendon stronger you need to do slow strengthening exercises.
References
[1] J. L. Cook et al., “A cross sectional study of 100 athletes with jumper’s knee managed conservatively and surgically. The Victorian Institute of Sport Tendon Study Group,” British journal of sports medicine 31, no. 4 (1997).

[2] M. Kongsgaard et al., “Corticosteroid injections, eccentric decline squat training and heavy slow resistance training in patellar tendinopathy,” Scandinavian journal of medicine & science in sports 19, no. 6 (2009).

[3] A. Del Buono et al., “Tendinopathy and inflammation: some truths,” International journal of immunopathology and pharmacology 24, 1 Suppl 2 (2011): 46.

[4] Ibid., p. 45.

[5] J. D. Rees, M. Stride, and A. Scott, “TENDONS: TIME TO REVISIT INFLAMMATION?,” British journal of sports medicine 47, no. 9 (2013).

[6] Giorgio Garau et al., “Traumatic patellar tendinopathy,” Disability & Rehabilitation 30, 20-22 (2008): 1616.

[7] Martin Hägglund, Johannes Zwerver, and Jan Ekstrand, “Epidemiology of patellar tendinopathy in elite male soccer players,” The American journal of sports medicine 39, no. 9 (2011).

[8] Sarah Morton et al., “Patellar Tendinopathy and Potential Risk Factors: An International Database of Cases and Controls,” Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine (2017).

[9] M. K. Drew and C. Purdam, “Time to bin the term ‘overuse’ injury: is ‘training load error’ a more accurate term?,” British journal of sports medicine 50, no. 22 (2016).

[10] Øystein Lian et al., “Performance characteristics of volleyball players with patellar tendinopathy,” The American journal of sports medicine 31, no. 3 (2003).

[11] Sarah Morton et al., “Patellar Tendinopathy and Potential Risk Factors: An International Database of Cases and Controls,” Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine (2017); E. Witvrouw et al., “Intrinsic risk factors for the development of patellar tendinitis in an athletic population. A two-year prospective study,” The American journal of sports medicine 29, no. 2 (2001); Peter Malliaras et al., “Patellar Tendinopathy: Clinical Diagnosis, Load Management, and Advice for Challenging Case Presentations,” The Journal of orthopaedic and sports physical therapy 45, no. 11 (2015): 895.

[12] van der Worp, H et al., “Jumper’s knee or lander’s knee? A systematic review of the relation between jump biomechanics and patellar tendinopathy,” International journal of sports medicine 35, no. 8 (2014).

[13] A. Ferretti, “Epidemiology of jumper’s knee,” Sports medicine (Auckland, N.Z.) 3, no. 4 (1986).

[14] Peter Malliaras, Lower Limb Tendinopathy Course (London, 31.10.2016).

[15] A. Ferretti, P. Papandrea, and F. Conteduca, “Knee injuries in volleyball,” Sports medicine (Auckland, N.Z.) 10, no. 2 (1990).

[16] Ivo J. H. Tiemessen et al., “Risk factors for developing jumper’s knee in sport and occupation: a review,” BMC research notes 2 (2009).

[17] Yu-Long Sun et al., “Temporal response of canine flexor tendon to limb suspension,” Journal of applied physiology (Bethesda, Md. : 1985) 109, no. 6 (2010); J. A. Hannafin et al., “Effect of stress deprivation and cyclic tensile loading on the material and morphologic properties of canine flexor digitorum profundus tendon: an in vitro study,” Journal of orthopaedic research : official publication of the Orthopaedic Research Society 13, no. 6 (1995); James H.-C. Wang, Qianping Guo, and Bin Li, “Tendon Biomechanics and Mechanobiology—A Minireview of Basic Concepts and Recent Advancements,” Journal of Hand Therapy 25, no. 2 (2012): 138; M. K. Drew and C. Purdam, “Time to bin the term ‘overuse’ injury: is ‘training load error’ a more accurate term?,” British journal of sports medicine 50, no. 22 (2016).

[18] A. Del Buono et al., “Tendinopathy and inflammation: some truths,” International journal of immunopathology and pharmacology 24, 1 Suppl 2 (2011): 45; Jessica E. Ackerman et al., “Obesity/Type II diabetes alters macrophage polarization resulting in a fibrotic tendon healing response,” PLOS ONE 12, no. 7 (2017); Tom A. Ranger et al., “Is there an association between tendinopathy and diabetes mellitus? A systematic review with meta-analysis,” British journal of sports medicine 50, no. 16 (2016).

[19] J. E. Taunton et al., “A retrospective case-control analysis of 2002 running injuries,” British journal of sports medicine 36, no. 2 (2002): 98.

[20] Esra Circi et al., “Biomechanical and histological comparison of the influence of oestrogen deficient state on tendon healing potential in rats,” International Orthopaedics 33, no. 5 (2009): 1466; Stephen H. Liu et al., “Estrogen Affects the Cellular Metabolism of the Anterior Cruciate Ligament,” The American journal of sports medicine 25, no. 5 (2016): 704; W. D. Yu et al., “Combined effects of estrogen and progesterone on the anterior cruciate ligament,” Clinical orthopaedics and related research, no. 383 (2001): 281.

[21] James E. Gaida et al., “Asymptomatic Achilles tendon pathology is associated with a central fat distribution in men and a peripheral fat distribution in women: a cross sectional study of 298 individuals,” BMC Musculoskeletal Disorders 11, no. 1 (2010).

[22] Peter Malliaras et al., “Patellar Tendinopathy: Clinical Diagnosis, Load Management, and Advice for Challenging Case Presentations,” The Journal of orthopaedic and sports physical therapy 45, no. 11 (2015): 895.

Picture Credit: https://www.injurymap.com/free-human-anatomy-illustrations
Martin Koban

About Martin Koban

I’m Martin Koban and I help people with knee pain get back to living a normal life. I’ve worked with professional athletes, recreational athletes, and regular people from all around the world.

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