PT on the Net Research

Swelling in the Knee


I have a potential client who has had problems with her knee swelling up in the past. When her knee swelled, it would cause the vastus lateralis to tighten. Over time, this has caused an imbalance in her quadricep and causes her knee to lock up from time to time. How would I correct this imbalance?


Very interesting question. Your question has me wanting to know a lot more about your client, as further information would help me to determine the cause of the swelling, which in turn would help in the treatment and rehabilitation of your client.

The main thing I would be seeking the answer to is why is the knee swelling up? Swelling of the knee is not typically normal unless there is some underlying cause, which could range from something as simple overuse and aggravation of the bursa or patellar tendon to a meniscal (cartilage) injury.

Only after more questioning and a musculoskeletal assessment would we be able to determine why the knee is swelling up. Some of the questions that would help to determine the cause of the knee swelling would include:

The reason it is important to ask these questions and carry out an assessment is because it will help guide you in making your diagnosis. Some would argue that the treatment and rehabilitation can only be as good as the diagnosis.

My first recommendation would be to refer your client out to a manual therapist (Osteopath or Physiotherapist) for this musculoskeletal assessment. They should be able to identify the exact extent of the injury and help give you instruction on the best way forward for treatment and rehab. If it is simply a patellar tracking disorder or irritation of bursa or patellar tendon, they will be able to treat this, correct any imbalances and give you advice on how best to treat this problem. If they suspect there is something a little more serious such as collateral ligament or meniscal damage, then they may refer your client off for an MRI Scan or Orthopedic assessment to determine the exact extent of the injury. Either way, your role as the personal trainer is essential in rehabilitating them back to being able to carry out everyday activities and exercise.

The most likely causes of this swelling are going to be:

Your client’s problem could lie directly with the knee itself (as described by the possibilities above) or it could in fact be secondary to a problem elsewhere. Your client needs to be put through a screening process to rule out any serious issues as well as determining whether the areas above or below (foot, ankle, hip, pelvis and lower back) are in fact creating, maintaining or aggravating this problem. Almost in all situations affecting the knee, there will be some biomechanical changes occurring in the foot, ankle, hip, pelvis or lower back. The body is one unit that works together, and when one area is affected, another has to work harder to compensate.

Even if there is an underlying mechanical problem directly at the knee (i.e., patellar tendonitis or bursitis issue), pain or inflammation around the knee will cause your client to develop aberrant motor patterns. Pain is the often the easiest and quickest way to inhibit any muscle activity - in this particular case, probably the vastus medialis. The response is the vastus lateralis and other lateral structures overpower the medial structures, resulting in tightening of the lateral structures, causing possible patellar tracking issues, possible swelling around the knee and altered gait patterns that will affect the muscles and joints at the feet, ankle, hip, pelvis and lower back.

Your job as a personal trainer could be to help try and identify any of these imbalances. This could be anything from identifying which muscles are tighter and which muscles are weaker. You should always compare left to right and look for asymmetries. You can start doing this by carrying out general stretch tests for the lower back, hip/pelvis and lower limb. By stretching tight muscles, you are helping to correct this balance. Some of the muscles that need to be tested include:

You could also test for muscle weakness and imbalances by carrying out a functional screen of the hip, pelvis and lower extremity. An easy way to do this would be by using the Reebok Movement Screens on the PTN web site. Simply observing one’s gait and getting your client to squat, lunge, single leg squat, step up/down will tell you a lot about their body and how they move. You should be looking for any glitches in movement, any hitching, cheating, lack of movement, etc in the hips, knees, foot/ankle left to right.

By carrying out these functional tests, you will be able to identify any general movement pattern problems and hopefully the underlying cause of these. Take the gluteus maximus and medius, for example. Both play an important role in stabilizing the hip and pelvis, and in individuals who have an imbalance, they may be suffering from lower back pain, hip, pelvis or knee pain. You may possibly observe the knees buckle inward on a one legged squat. You may notice the hip drop on a step up. If you are interested in learning more about these screening processes and correcting any movement problems, check out the work of Gary Gray or Gray Cook. Often the screening process itself can be turned into an exercise program itself. Identify the weak muscles and use your knowledge of exercises to go about strengthening these areas.

By working in conjunction with a manual therapist, you will find that you will be able to correct these imbalances much quicker and help get your get your client back on track to achieving her goals.

Failure to do something about your client’s injury could well lead to chronic knee pain, early degeneration in the knee or possibly the development of a secondary problem in the foot, ankle, hip, pelvis or lower back.