Knee Painby John Howick
One of the most common complaints I see in young athletes is knee pain. Often it is due to muscle imbalance secondary to a growth spurt and other times it is just from overuse. Most of the conditions and treatment I will talk about apply to adults but one of the conditions is specific to youngsters.
Patellofemoral Pain Syndrome (also know as Chondromalacia Patella or "Runners Knee") is the most common cause of knee pain in both children and adults. It is an irritation of the undersurface of the kneecap (patella) and the joint surface of the thighbone (femur). The knee cap sits within the tendon of the front thigh muscle (quadriceps) and it slides up and down a groove in the femur as the knee is bent or straightened. If the quadriceps muscles are too tight they can increase the pressure on the kneecap causing pain. If the kneecap is not centered in the groove it can cause an uneven pressure which can be painful. The kneecap can get "out of alignment" due to: tight quadriceps, hamstrings and iliotibial band, weak inner quadriceps (VMO), weak outer hip muscles (gluteus medius), tight calf muscles and flat feet (over-pronation). All these factors respond to appropriate exercise. Occasionally a child may present with true alignment problems within the bones themselves. Exercise can still often be helpful to compensate for these problems or to prevent them from worsening. Good running shoes and simple over the counter insoles can help with over-pronation. Patellofemoral pain is not a serious problem and it does not indicate that the child will later develop early arthritis in the knee. In most cases children will "grow out" of the problem once their strength, coordination and flexibility improves. Surgery is very rarely indicated to correct knee cap alignment or clean up the irritated joint surfaces.
Patellar Tendinopathy (also know as "Jumper's Knee") is an irritation of the tendon which runs from the bottom of the kneecap to the shin bone (Tibia). The tendon is often very tender to touch and becomes more painful with sprinting, kicking, jumping and running down hills. Walking down stairs can also be painful. Sometimes the tendon becomes swollen and thickened. This condition is caused by the same factors listed above for Patellofemoral pain. Treatment will be listed below. This problem often responds very well to wearing a small strap wrapped around the knee to decrease the force on the tendon.
Osgood-Schlatter's Disease. This condition is only found in children. As a child develops, their limbs are transformed from mostly cartilage as a baby to completely bone when they reach adulthood. At the front of the shin there is bump where the patellar tendon attaches called the tibial tuberosity. This area of bone develops separately from the main portion of the tibia. When adolescents become heavily involved in sports, their tendons pull on this bone growth area and can produce inflammation and swelling. The bone can build up and form a larger than normal bump. In the past, children with Osgood Schlatter's were pulled out of all activity for a year. It was found stopping activity did not improve recovery. In fact in every case, Osgood Schlatter's will eventually just go away on it's own. The only long-term consequence is the presence of a larger "shin bump" which usually causes no problems as an adult. What is now recommended is that activity be kept to a level that does not cause pain lasting after the sport is completed. If the child complains of pain at night disturbing their sleep or they limp the day after activity they need to take a break from their sport until the symptoms settle. This condition may respond to the patellar tendon strap mentioned above. Soft kneepads may help to protect a very tender shin. Gentle exercises help improve muscle imbalance but care must be taken not to put too much force through the irritated area.
Treatment for all these conditions is similar. Ice is used to control pain and swelling. Rest is important to settle down the irritation so that specific exercises can begin. Proper stretching techniques should be taught for the quadriceps, hamstrings and calf muscles. Gentle strengthening exercise should then be progressed to improve inner quadriceps (VMO) and outer hip strength and control. If a pain persists the knee cap or patellar tendon can be taped to improve alignment. Parents can be taught how to tape the knee or specific Patellofemoral braces can be purchased. These braces have a hole for the patella and a felt "donut or horseshoe" which keeps the patella in a better position. A physiotherapist can help you or your child develop an appropriate rehabilitation program. Children often recover very quickly and may only require a few treatments.
When dealing with children suffering overuse injuries we must remember that sometimes kids today are just doing a bit too much. If a child does not respond to ice and appropriate rehabilitation, parents may need to take a look at the number of hours a young athlete is participating in intense sport. Taking a break or winding things down a little may be just what's needed.