What Is Plica Syndrome?

by Joy Keller on Dec 15, 2016

Body Lab

This irritating knee issue can be hard to pinpoint but fairly simple to manage.

Clients sometimes experience general pain in the knee during or after an exercise session, and while it's not within your scope of practice to diagnose, a broad understanding of issues that affect this important joint can be helpful. Here's a snapshot of plica syndrome.

Plica is a fold of synovial tissue that's a "remnant" of embryologic development. The knee is initially divided into three compartments by membranes, which are then resorbed by the third or fourth month of fetal life (Scuderi et al. 1997). In up to 60% of people, however, this doesn't happen. While that will not always cause problems, sometimes it will.

In short: Of the adults with this unabsorbed membrane around the knee (usually mediopatellar), a few will face discomfort:

  • pain in the front of the knee, often toward the inside, especially with kneeling, squatting or rising from a seated position
  • catching, locking and clicking
  • pain and tenderness under the kneecap
  • inflammation and tightness

How to Help Clients

If you suspect a client has plica syndrome, refer him or her to a qualified medical professional and follow the professional's advice. Also, reassess the client's biomechanics and review your programming. Revise it to include activities that are less likely to irritate and inflame the plica. Mike Bracko, PhD, a Calgary, Alberta—based exercise physiologist, advises avoiding repetitive-knee-flexion pursuits like running, biking, elliptical training or stair climbing. "It's important to maintain quad strength, however," says Bracko. "Program light-weight, half-range-of-motion (45-degree) squats or lunges (closed-chain exercises), 10 repetitions, 1–2 sets."

Also, as part of a corrective-exercise program, look for muscular imbalances in the quadriceps and hips, as well as compromised mobility.


Scuderi, G.R., McCann, P.D., & Bruno, P.J. 1997. Sports Medicine: Principles of Primary Care. St. Louis: Mosby.

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About the Author

Joy Keller

Joy Keller IDEA Author/Presenter

Joy Keller is executive editor of IDEA Fitness Journal and IDEA Fit Business Success, and is also a certified personal trainer, indoor cycling instructor, yoga teacher (RYT 200) and Reiki Master. Joy joined IDEA Health & Fitness Association in 2002, and brought with her a wealth of information about how to fine-tune communication channels, after having spent her formative career years specializing in business-to-business journalism. Before she even graduated with honors from the respected University of Georgia journalism school, Joy was offered a job at one of the most successful trade publishing companies in the southeast, Shore Varrone, Inc. She made her mark in the automotive aftermarket industry as a creative thinker and journalist with an intuitive knack for researching and understanding niche audiences. Joy has worked on several titles, including Auto Trim & Restyling News, Truck Accessory News, Digital Output Magazine, Retail & Construction News, Miata magazine, Ford Racing, and many more. Her passion, however, lies with health and fitness. She was the associate editor of ACE Certified News while working at the American Council on Exercise, and transitioned that publication from a newsletter to a magazine. She has enjoyed 17 years at IDEA, where she has launched several publications, including the award-winning Inner IDEA Body-Mind Spirit Review, IDEA Pilates Today and IDEA Fit Business Success. Joy is a content creator and media 2.0 advocate who takes pride in discovering the unique information needs of qualified audiences, and she is dedicated to serving those needs while following the highest available standards.