Patellofemoral Pain Syndrome is sometimes called runners knee, sometimes it is called jumpers knee, sometimes it is called anterior knee pain and it has also been described as chondromalacia patella. This description is used for all kinds of pain in and around the front of the knee, especially around and under the kneecap or the patella. Anyone can get knee pain, but it mainly affects people that are more active like runners, dancers, basketball players and any other sporting activity. It is also very common in people in their teens and is more common in females than young males. It can also affect both knees but more commonly only one knee seems to be affected.
Causes
Patellofemoral pain very often occurs without injury, but it may happen through injury or as a result of trauma to the knee. It is always difficult as to the cause of patellofemoral pain as there could be more than one factor. It could be that the person starts a new or different activity, it may be an increase in activity, or the training times are longer, or the number of training periods increase. With all this information you can see why it is so difficult to find or know what the cause brings patellofemoral pain on. The knee joint is the middle joint of the leg, it is between the hip joint above and the ankle joint below. This makes the knee joint a central point of axis therefore any alterations in movement patterns in the hip or ankle may well have a bearing on the mechanical effects on the knee joint. Below is a list of possible causative factors:
- Abnormal Mechanics
- Footwear
- Training Methods
- Muscle Imbalance
- Hip Control
- Tight Muscles
- Ankle Instability
- Weak Muscles
All these factors may influence the mechanism of knee joint by increasing the mechanical forces at the patellofemoral joint.
PATELLAR TRACKING
The Patella or kneecap runs in a groove with the femur as the knee bends and straightens. This tracking mechanism is due to the muscle’s, ligaments and tendons in and around the patella that keeps the movement fluid and keeps the patella in this groove and in a pain free range of motion. This tracking mechanism can be disrupted with the resulting factor which is pain. Various treatment methods are put forward to aid and help the patella tracking and help reduce the pain.
PATELLA ALTA AND BAJA
These are medical names given to the positioning of the patella in relationship with the knee joint.
ALTA is the name given when the patella rides higher than what would be it in a normal position.
BAJA is the name given when the patella is lower than what should be the normal position. These different positions of the patella in the knee do not tend to cause trouble with the tracking mechanism of the knee joint.
BURSAE
This is a thin membrane sack located at friction points between a bone and soft tissue. The two common bursae at the front of the knee joint which are normally affected are the supra patella bursa, which sits above the patella and the infra patella bursa which is located below the patella. These Bursae can and very often do become inflamed which results in bursitis. The common symptoms of bursitis are swelling, pain and normally without redness and feeling hot. The swelling around the knee itself might affect the tracking of the patella.
CHONDROMALACIA PATELLA
The patella (kneecap) sits at the front of the knee joint and the underlying surface articulates with the condyles of the femur. It moves or tracks in grooves on movement as in walking or running. The underlying surface of the patella is covered by hyaline cartilage. It is known that the hyaline cartilage matrix is made of type ll collagen and chondroitin sulphate. The function of hyaline cartilage is to protect, support and allow friction free movement of a joint. Irritation of the cartilage on the underside of the patella (kneecap) can lead to knee pain. This is a common cause of anterior knee pain (AKP) in young people.
Signs and Symptoms
Chondromalacia patella is a common cause of knee pain. It is often referred to as patellofemoral pain syndrome.
- Pain in and around the knee
- Crepitus this is a grinding, grating, creaking, cracking and crunching sounds on movement.
- Aggravation through activity
- Raising from a chair
- Pain on Stairs going up and coming down.
- Feeling of stiffness in the knee.
How is chondromalacia Patella diagnosed?
Chondromalacia Patella must be suspected in young people that complain of anterior knee pain especially teenage females and young adults.
X-rays and MRIs are normally used to rule out other abnormalities and to confirm a diagnosis.
PATELLA SUBLUXATION
Patella subluxation is a partial dislocation of the patella (kneecap). In years of clinical practice, I have never seen a patient who has had a medial subluxation, that is where the patella (kneecap) partially dislocates to the inside of the knee joint. I have only had experience with patients who have had lateral patella subluxation. This is not to say it can never happen, but it must be a very rare occurrence. A few unfortunate patients have had to have a knee operation, which is an operation to rectify lateral patella subluxation. Lateral subluxation causes irritation of the under surface of the patella which causes patellofemoral pain. This type of operation is called a lateral release.
This operation is done to treat or rectify what is thought to be patella maltracking caused by tightness in the structures on the outer side of the patella (kneecap). Lateral release surgery involves releasing the tight retinaculum on the outer side of the kneecap. The lateral retinaculum is a fibrous tissue on the lateral (outer) side of the kneecap. There is also a medial (inner) side retinaculum and these structures help support the position of the kneecap as it tracks in the grooves of the femur. There are several factures as to why the lateral retinaculum gets tight and pulls the patella (kneecap) to the outer side. As the patella (kneecap) shifts to the outer side of the knee it is thought this abnormal movement stretches the inner structure of the knee like the medial retinaculum.
WHAT ARE THE SYMPTOMS?
Here are some of the symptoms that might be experienced following a patella subluxation.
- Pain at the front of the knee
- Swelling
- Feeling of stiffness in the knee joint
- Knee or leg giving way
- Feeling of instability
- Clicking sensation of the patella
CAUSES OF PATELLA SUBLUXATION
Patella subluxation mainly affect the young and active people and is common in jumping, extreme activity and contact sports. The problem is that after an initial injury, the chances of it happening again or even dislocating are very high. Conservative approach is the first choice of treatment and this begins with R.I.C.E. which stands for:
- Rest
- Ice
- Compression
- Elevation
Initially you might need the use of crutches for the first few days.
Over the counter medications such as painkillers or anti-inflammatories.
Start gradual knee exercises.
Recovery may take 4 to 6 weeks before returning to sport.
PATELLA DISLOCATION
Patella dislocations are common and is often caused by knocking the patella (kneecap) or a direct blow to the knee. Other causes like a sudden change in direction, jumping and landing on a twisted knee can bring about a dislocation of the patella.
SIGNS AND SYMPTOMS
When the patella (kneecap) dislocates normally laterally (outer side) the patella will look out of place and be on the outer side of the knee. In a lot of circumstances, it may pop back into place very soon after the trauma.
Severe pain
Swelling
Not able to straighten the knee
Not able to walk
A popping sound and sensation.
If the patella remains dislocated you will need to go to hospital, if the patella pops back into place it would still be advisable to seek medical advice in the first instance. The hospital might want to X-ray the knee to rule out any other damage. They may administer crutches; get you fitted with a knee brace and prescribe pain medication.
Treatment and Rehabiliatation
Surgery is usually only necessary if there is a diagnosis of a fracture or other structural damage.
Surgery might be done if you have a history of recurrent subluxations or if you have dislocated the patella before.
A knee brace may be needed for a week or more for comfort in walking.
Recovery usually takes about 6 to 8 weeks maybe longer before returning to sports.
RECOMMENDED EXERCISES
Achilles Stretch
Stand facing a wall at arm’s length, palms of the hands against the wall.
Take a pace forward with the unaffected leg and knee.
Bend the unaffected knee until you feel a stretch in the calf muscle.
Hold this position for 20 seconds and then relax.
Repeat the exercise x 3.
Iliotibial Band Stretch
Standing in an upright position, hold onto a works surface for balance.
Cross the affected knee behind the opposite leg and place the foot flat on the floor.
Lean over to the unaffected side until you feel a stretch on the affected side.
Hold this position for 20 seconds and then relax.
Repeat the exercise x 3.
Quadriceps Stretch
Standing side on at a work surface, have the unaffected knee on the inside.
Grasp the ankle of the affected knee pull the foot up towards the buttock.
Slowly pull the leg backwards until you feel the stretch at the front of your thigh.
Hold this position for 20 seconds and then relax.
Repeat the exercise x 3.
ATL Physio advises that stretching exercises are to be done before and after these strengthening exercises.
STRENGTHENING EXERCISES
Deep Squats
Stand side on at a work surface.
Rest the inner hand on the work surface for balance.
Feet shoulder width apart.
Slowly squat down as far as you can.
Remain in a squat position for 2 to three seconds.
Then stand up and repeat the exercise x 10.
Semi Squats
Stand side on at a work surface.
Place a ball between the knees.
Squeezing a ball between the knees.
Slowly bend the knees and squat down to 90 degrees.
Hold the squat position for 2 to 3 seconds.
Then stand up and repeat the exercise x 10
ADDUCTOR RESISTED EXERCISE
Fix or anchor a resistance band to a table leg or something that will not move.
Place the resistance band around the ankle of the affected side.
Stand with feet astride with no slackness in the resistance band.
Use the back of a chair for balance if needed.
Bring the foot with the resistance band together and crossing the other leg.
Take the foot in front of the other leg and return to the start position.
This time bring the foot together crossing the other leg behind.
Return to the start position (see our video for instruction)
Repeat the exercise alternating crossing the leg front and rear 10 to 20 times.