What causes it?
Generally speaking, patellofemoral dysfunction occurs under one of two broad circumstances; either when the patella is forced with excessive pressure against the underlying femur or when it is pulled excessively either laterally or medically against the groove. In either case, this would cause irritation and abrasion of the cartilage (underside) of the patella, resulting in inflammation and pain. Quite often this pain is experienced in the patella tendon that runs through from the patella to the shin bone.
The management and prevention of PFD begin with an understanding of the risk factors that predispose to this injury. Excessive pressure of the patella against the underlying femur generally results from excessively tight quadricep muscles which is best addressed through massage to local soft tissues and appropriate stretching exercises. There are several risk factors that can cause the patella to ride excessively on the side of the groove, invariably along the lateral (outside) side of the groove. There are three primary causes of improper patellar tracking:
- Weakness of the inner quadriceps muscle, vastus medialis obliquus (VMO)
- Restricitive iliotibial band
- Improper lower extremity biomechanics (hip to feet must be considered)
When weakness of the VMO is present, the lateral pulling forces of the vastus lateralis (the quadricep muscle on the outer thigh) and the iliotibial band result in the lateral tracking of the patella.
Of all of the conditions that predispose to lateral tracking of the patella, there are numerous studies that confirm the fact that biomechanical abnormalities are potentially the most common and significant of PFD.
It is common to relate biomechanical problems, most commonly excessive subtalar (joint in the foot) pronation. This causes the arch of the foot to flatten or roll in resulting in internal rotation of the hip. Internal rotation of the hip causes the quadriceps to pull somewhat obliquely rather than in a functional straight position which leads to maltracking of the patella.
This is an easy thing to observe during functional movements like a single legged squat or running. During these movements the foot and the knee will track in different directions. When the foot is turned out in relation to the knee, or the knee turned in, in relation to the foot, this is a significant risk factor for patellofemoral dysfunction.
How can it be managed?
Management of this problem falls into three broad categories:
- Acute management
As with most overuse injuries, the acute (initial) phase is managed with significant activity changes. Generally, activities that induces symptoms are discontinued. During this phase, ice, non-steroidal anti-inflammatory medications and physiotherapy led treatment and exercises/stretches are recommended. There are also a number of patellofemoral sleeves available that provide warmth and compression while helping the patella track more efficiently in its groove.
When biomechanic faults are identified as possible causes for this problem, this should immediately be addressed. Treatment, exercises and orthotic support (if deemed necessary) should then mimic the biomechanical needs.
A useful tip when attempting to assess the severity of the injury and the progress and success of treatment is to monitor two particular symptoms. The first is related to a common complaint of pain after sitting for varying periods of time. The period of time required to produce the symptoms should improve to the point when it is not felt at The reason why pain is felt in sitting by PFD sufferers is because the patellofemoral joint is under the highest degree of compression when the knee is bent 90 degrees. This increased pressure will contribute to more pain from the already inflamed patellofemoral joint.
The other symptom frequently reported by patients is pain going up and down stairs or hills. This occurs because, again, the patellofemoral joint is under higher levels of compression due to increased quadricep activity and degree of knee flexion when going up and down stairs and hills. Both of these symptoms can be very useful indicators as to the success of treatment and helpful determinants as to the person’s ability to return to activity.
As symptoms improve, rehabilitation of those structures predisposing to this injury can be initiated. Strengthening of the VMO is a key factor in the rehabilitation of this injury, and numerous studies have been performed to determine which of the many exercises available for this purpose are indeed most effective and least irritating. The medical literature indicates that the three most beneficial exercises are:
1. Static tightening the VMO when seated or lying with the knee extended for a period of 7-10 seconds, and repeated 10-15 times per session and repeated several times per day
2. “Wall sits/squats”– standing with your back to a wall with 20-30 degrees of knee flexion while squeezing an object such as a volleyball between the knees. The squeezing of the object between the knees is important because this recruits the groin muscles (adductors) which are an attachment point of the VMO. As a result, by tightening the adductors, the patient is indeed selectively strengthening the VMO relative to the other quadriceps. Hold as long as the correct muscles are being recruited until fatigue. Repeat several times throughout the day.
3) Side-step-ups (generally when symptoms improve sufficiently) with varying height of step to be determined by the status of the patient and the patient’s injury. This is an excellent exercise to selectively recruit the VMO and gluteus (buttock) muscles. Repeat 10-30 times several times a day.
n addition to exercise rehabilitation, stretching is also important to reduce muscle tensions onto the Patellofemoral joint. The following stretches are effective during PFD rehabilitation.
1) Iliotibial (IT) band stretch – standing, place the pelvis in neutral and cross your legs with the leg being stretched behind. Slide the hip sideways to towards the leg being stretched. Reach the same side arm of the leg being stretched up and over the head leaning the body with it to the opposite side while slightly leaning forward.
2) Glutes stretch – aitting with knees approximately bent at 90 degrees, place the ankle of one leg onto the opposite leg’s knee.
3) Quadriceps stretch – pull heel towards buttocks, find the pelvic neutral position and pull the knee back towards the other knee to increase stretch.
4) Hamstring stretch – place heel of the leg to be stretched on a step/stair. Tighten the front of the thigh and move the foot towards the body bending from the ankle. Tilt the pelvis back and bend forward from the hips keeping the back straight.
As symptoms subside and normal function through appropriate stretching and strengthening exercises is joined with appropriate biomechanic intervention, conditioning exercise can be advanced. A gradual return to running/sport should be introduced through a walk-run program which should involve initially running on flat surfaces only and beginning with a fairly modest pace. As the athlete progresses in their work-outs, hill training should be the last aspect of training to be introduced, since this is the area of greatest stress to the patellofemoral joint.
Elite Therapy is a multidisciplinary sports therapy and physiotherapy clinic in Coventry. We treat a range of injuries both sporting and non-sporting as well as back, neck and musculoskeletal pain. Elite Therapy’s services include assessment and diagnosis, physiotherapy, sports therapy, massage therapy, taping and ultrasound. There is also an on-site rehabilitation gym and studio for the Pilates and yoga classes.