Osgood Schlatter’s Disease, Osgood Schlatter’s Syndrome, OSD
Osgood Schlatter’s Syndrome is a knee condition of athletic adolescent boys and girls, affecting up to 20% of this active teenage group. In non-athletic children, the incidence is closer to 5%. It is self-limiting in nature and managed by simple reduction in activity, ice, anti-inflammatory drugs and bracing.
The ratio of boys to girls with Osgood Schlatter’s Syndrome is 3:1, with the ages most commonly affected coinciding with the growth spurts of boys and girls.
What Is Osgood Schlatter’s Syndrome?
The tibial tubercle or tibial tuberosity is a bony prominence just below the knee at the front. It is the point where the quadriceps muscle tendon inserts into the upper tibia, and takes all the force of the knee muscle’s activity. When we stand up, go up stairs or run, all the force of our major knee power muscle is transmitted through the tibial tubercle.
In adults this bony lump is firmly fixed to the shin bone, but in adolescents there is a growth plate present. Repeated vigorous activity causes traction (pulling) on this growth plate and this is thought to cause inflammation and pain. It usually settles once the growth plates fuse to the shin bone as we stop growing, at about 14 to 18 years of age.
Osgood Schlatter’s Syndrome and Sport
Many vigorous sports demand strong contractions of the major knee straightening muscle, the quadriceps. This pulls on the immature tibial tubercle and small stress fractures or pulling injuries can occur.
As the tubercle is pulled forward, the healing process forms bone behind it, leading to a more prominent tubercle. If the person goes on with sport, the tibial tubercle can become very prominent.
If the tubercle becomes enlarged, it can look obviously abnormal as well as getting in the way of functional activities such as kneeling. Kneeling puts all the weight through these enlarged bony areas and that is usually to uncomfortable to do for very long. In severe cases the bony lump may become separated from the shin bone and stay as a long-term unhealed area with pain.
How Does Osgood Schlatter’s Syndrome Show Up?
Knee pain below the knee at the front is most common complaint of people with Osgood Schlatter’s Syndrome. Pain is worse doing vigorous activities such as running and jumping, and better with rest or doing less stressful activities.
Sporty people, keen on lots of strong activity, are the worst affected. There may often be no particular incident or cause for the pain and the symptoms are often variable and vague in nature.
Physically there is tenderness over the tibial tubercle, with or without swelling of the area. The tubercle may be enlarged and pain can be brought on by strong contraction of the quadriceps muscle or by an activity such as jumping.
The physical examination is very specific with point tenderness over the tibial tubercle. Other physical examination findings may include the following: There are usually no other abnormal findings in the knee.
The cause of OSD is unknown but it is thought to be the result of repeated knee muscle contraction, causing small pulls or tears of the cartilage and fibrous parts of the growth plate of the tibial tubercle. Running and jumping are two of the most common sporting activities which are implicated in causing this syndrome.
Treatment Of Osgood Schlatter’s Syndrome
Rest or modification of activity is the mainstay of treatment. If the pain is going to be managed well, a reduction in sport is going to be necessary. In some cases sport has to stop and the person may be put into a plaster of Paris or a splint to rest.
A small knee brace called an infrapatellar strap can be used to alter the lines of force through the area, reducing the strain on the tibial tubercle.
Surgery is uncommon but can be used to remove unhealed areas of the tibial tubercle or to fix the tibial tubercle to the tibia.
The pain may take up to 6 months to two years to settle. If someone returns to their activity too soon, they may cause a recurrence of the condition. Athletes can work on improving the flexibility and strength of the quadriceps and hamstring muscles.
Initial return to sport may need to be reduced in intensity and high risk activities may need to be avoided.
The Long-term Outlook For Osgood Schlatter’s Syndrome
Overall the outcome is good. The syndrome usually settles once the growth plate at the tibial tubercle solidifies into bone, mostly by 18 years of age. Long-term consequences are uncommon, but include a very prominent tibial tubercle and the inability to kneel on hard surfaces due to the pressure on the bony point.
Osgood Schlatter’s Syndrome is a painful problem of the knee in sporting youngsters and is self-limiting in nature. Acute episodes can be managed by rest, ice and anti-inflammatory drugs. Daily stretching and strengthening of the quadriceps and hamstrings can be useful.