Why Your Sporty Teenager’s Knee May Be Hurting

If they participate in sports, it could be Osgood-Schlatters disease

Image/MedikaLife/CC License

A father of one of your children's basketball friends gives you a call out of the blue. Their fourteen-year-old has suddenly developed a bump on their left knee. It’s painful and is restricting their child's movement. Worst of all, playing basketball seems to be aggravating it. Chances are, it’s Osgood-Schlatters disease.

What is Osgood-Schlatter’s disease?

Osgood-Schlatter’s disease, also known as osteochondrosis or traction apophysitis of the tibial tubercle, is a common cause of anterior (front) knee pain in the skeletally immature (typically between the ages of 8 and 15) athletic population. Common sports seen in association with the condition include:

• Basketball
• Volleyball
• Sprinters
• Gymnastics
• Football

The condition will normally get better by itself, but may in rare instances persist into adulthood, when surgery may be considered as an option to remove the bump.

Image courtesy of Medika

Symptoms

Typically, this condition occurs in children between the ages of 8 and 15 that are exposed to activities that include sprinting and jumping, actions that jar the knee. Pain begins as a dull ache localized over the tibial tubercle (see image above), gradually increasing with activity. This will occur gradually and does not require any blow or trauma to the area.

Pain is increased particularly by running, jumping, direct knee trauma, kneeling, and squatting. An enlarged prominence (bump) at the tibial tubercle is present with tenderness over the site of the patellar tendon (see image above) insertion. Poor flexibility of the quadriceps and hamstrings may be present, and as a result, may in some instances contribute to the condition. Knee extensions and active or passive knee flexion will be painful.

Treatment / Management

Ultimately, the condition is self-limiting (heals on its own) but may persist for up to 2 years until the apophysis (a natural protuberance or bump from a bone) fuses. Treatment includes relative rest and activity modification from the offending activity as guided by the level of pain. There is no evidence to suggest that rest speeds up recovery, but activity restriction is effective in reducing pain.

Patients may participate in sports as long as the pain resolves with rest and does not limit sports-associated activities. Local application of ice and Non-Steroidal Anti-inflammatory Drugs (NSAIDs) can be used for pain relief. A protective knee pad may be worn over tibial tubercle (see image)to protect from direct trauma.

Hamstring stretching and both quadriceps stretching and strengthening exercises can be a useful adjunct. If the pain does not respond to conservative measures, your doctor may recommend physical therapy. In severe, prolonged cases a short period of knee immobilization may be considered. There is no evidence to recommend injection therapy or surgical intervention for Osgood-Schlatter disease.

Stretching for rehabilitation

Image Courtesy of Medika

These exercises, provided with thanks by the Summit Medical Group, will offer relief. You can start stretching the muscles in the back of your leg by doing the hamstring and calf stretches right away. When you have only a little discomfort in the upper part of your shin, you can do the rest of the exercises.

• Hamstring stretch on wall: Lie on your back with your buttocks close to a doorway. Stretch your uninjured leg straight out in front of you on the floor through the doorway. Raise your injured leg and rest it against the wall next to the door frame. Keep your leg as straight as possible. You should feel a stretch in the back of your thigh. Hold this position for 15 to 30 seconds. Repeat 3 times.
• Standing calf stretch: Stand facing a wall with your hands on the wall at about eye level. Keep your injured leg back with your heel on the floor. Keep the other leg forward with the knee bent. Turn your back foot slightly inward (as if you were pigeon-toed). Slowly lean into the wall until you feel a stretch in the back of your calf. Hold the stretch for 15 to 30 seconds. Return to the starting position. Repeat 3 times. Do this exercise several times each day.
• Quadriceps stretch: Stand at an arm’s length away from the wall with your injured side farthest from the wall. Facing straight ahead, brace yourself by keeping one hand against the wall. With your other hand, grasp the ankle on your injured side and pull your heel toward your buttocks. Don’t arch or twist your back. Keep your knees together. Hold this stretch for 15 to 30 seconds.
• Rectus femoris stretch: Kneel on your injured knee on a padded surface. Place your other leg in front of you with your foot flat on the floor. Keep your head and chest facing forward and upright and grab the ankle behind you. Gently bring your ankle back toward your buttocks until you feel a stretch in the front of your thigh. Hold 15 to 30 seconds. Repeat 2 to 3 times.
• Straight leg raises: Lie on your back with your legs straight out in front of you. Bend the knee on your uninjured side and place the foot flat on the floor. Tighten the thigh muscle on your injured side and lift your leg about 8 inches off the floor. Keep your leg straight and your thigh muscle tight. Slowly lower your leg back down to the floor. Do 2 sets of 15.
• Prone hip extension: Lie on your stomach with your legs straight out behind you. Fold your arms under your head and rest your head on your arms. Draw your belly button in towards your spine and tighten your abdominal muscles. Tighten the buttocks and thigh muscles of the leg on your injured side and lift the leg off the floor about 8 inches. Keep your leg straight. Hold for 5 seconds. Then lower your leg and relax. Do 2 sets of 15.
• Knee stabilization: Wrap a piece of elastic tubing around the ankle of your uninjured leg. Tie a knot in the other end of the tubing and close it in a door at about ankle height.
• Stand facing the door on the leg without tubing (your injured leg) and bend your knee slightly, keeping your thigh muscles tight. Stay in this position while you move the leg with the tubing (the uninjured leg) straight back behind you. Do 2 sets of 15.
• Turn 90 degrees so the leg without tubing is closest to the door. Move the leg with tubing away from your body. Do 2 sets of 15.
• Turn 90 degrees again so your back is to the door. Move the leg with tubing straight out in front of you. Do 2 sets of 15.
• Turn your body 90 degrees again so the leg with tubing is closest to the door. Move the leg with tubing across your body. Do 2 sets of 15.
• Side-lying leg lifts: Lie on your uninjured side. Tighten the front thigh muscles on your injured leg and lift that leg 8 to 10 inches (20 to 25 centimeters) away from the other leg. Keep the leg straight and lower it slowly. Do 2 sets of 15.
• Clam exercise: Lie on your uninjured side with your hips and knees bent and feet together. Slowly raise your top leg toward the ceiling while keeping your heels touching each other. Hold for 2 seconds and lower slowly. Do 2 sets of 15 repetitions.

For Healthcare Professionals

Epidemiology

Osgood-Schlatter’s disease is one of the most common causes of knee pain in the skeletally immature, adolescent athlete. Onset coincides with adolescent growth spurts between ages 10 to 15 years for males and 8 to 13 years for females. The condition is more common in males and occurs more frequently in athletes that participate in sports that involve running and jumping. In adolescents, age 12 to 15, the prevalence of Osgood Schlatter disease is 9.8% (11.4% in males, 8.3% in females). Symptoms present bilaterally in 20% to 30% of patients.

Pathophysiology

The tibial tubercle develops as a secondary ossification center that provides attachment for the patellar tendon. Bone growth exceeds the ability of the muscle-tendon unit to stretch sufficiently to maintain previous flexibility leading to increased tension across the apophysis. The physis is the weakest point in the muscle-tendon-bone-attachment (as opposed to the tendon in an adult) and therefore, at risk of injury from repetitive stress.

With repeated contraction of the quadriceps muscle mass, especially with repeated forced knee extension as seen in sports requiring running and jumping (basketball, football, gymnastics), softening, and partial avulsion of the apophyseal ossification center may occur with a resulting osteochondritis.

The appearance and closure/fusion of the tibial tubercle occurs in the following sequence pattern:

• Tibial tubercle is entirely cartilaginous (age < 11 years)
• Apophysis forms (age 11 to 14 years)
• Apophysis fuses with the proximal tibial epiphysis (age 14 to 18 years)
• The proximal tibial epiphysis and tibial tubercle apophysis fuses with the rest of the proximal tibia (age > 18 years)

Refractory Cases

In up to 10% of cases, symptoms may persist >1–2 years beyond skeletal maturity. In skeletally mature patients with persistent symptoms, ossicle excision may be performed.