Osgood-Schlatter Disease (OSD)
(Other terms for it are: idiopathic osetochondrosis of the tibial tubercle, traction apophysitis, apophysitis of the tibial tubercle, osteochondritis juvenilis)
It is important to realize that the term “disease” is a misnomer as the problem with Osgood-Schlatter disease is not systemic or infectious but mechanical in nature. It is a traction or pulling of the apophysitis of the tibial tubercle (bony prominence on the top part of the shin bone) at the site of where the patellar tendon inserts. It is the result of either the sudden or continuous strain on the patellar tendon caused by the overpull of the quadriceps mechanism, particularly during growth spurts.
This is the most common cause of knee pain in adolescent athletes, especially in sports requiring repetitive quadriceps contraction such as jumping, kicking like basketball, soccer and volleyball. It occurs in a 3:1 ratio of male to female and common between the ages of 8-13 in females and 10-16 in males. The condition is associated with the growth spurt of puberty and affects the take-off leg most commonly in jumping sports.
- Typically with repetitive movements from training in sports there is something called a stress reaction of the apophysis (the site of where the patellar tendon attaches) which is a constant pulling of the patellar tendon (ligament) at the tibial tubercle.
- Adolescent growth spurt
- Recurring microfractures of the tibial tubercle
- Strenuous repetitive quadriceps activity
- Short patellar tendon
- Muscle tightness or spasm in specific muscles such as hamstrings, quads, gastrocs
- Abnormal Q-angle
- Patella alta (high sitting patella on the femur bone)
OSD can sometimes be difficult to diagnose. Other disorders can present similar symptoms such as chondromalacia patella, patellar tendonitis, quadriceps tendon avulsion, infra or prepatellar bursitis, stress fracture of proximal tibia. So how does a physical therapist tell if it is in fact OSD and not one of the other possibilities. Taking into account some of the information already discussed and understanding the clinical presentation of this disorder is imperative to receiving a proper diagnoses.
First, there is localized swelling over the tibial tubercle. Second, often times there is malalignment of the leg such as pronated feet or genu valgum (valgus deformity). Third, it is common to see a high-rising patella (patella alta) and there may be atrophied quadriceps muscle if it is a longstanding problem. Fourth, visibly you can see an abnormal gait pattern (limping). You may see the person with OSD walk with a flexed knee or with the knee locked in extension to avoid quadriceps activity which will trigger the pain. Fifth, when touching the area of the tibial tuberosity or site of patellar tendon, tenderness is evident and it is graded from slight to severe. Lastly, there is also warmth in the area. X-rays will ultimately confirm the diagnosis and determine the severity of the problem.
Treatment follows a 3 step process:
1) decrease pain
2) increase flexibility
3) return to normal activities
The first thing that needs to be understood is that pain needs to be reduced. One should avoid physical activities requiring deep knee bending or resisted knee extension for 1-4 months. Restrict running, stairs and walking barefoot before the age of 15. You must wear supportive shoes and not loose sneakers. Iontophoresis is a good option because it inhibits pain from the electrical current. The current is localized to the small area where the OSD is present and is a method of administering medication without injecting the tendon junction, thus avoiding tendon damage. Medication prescribed by your doctor would likely be NSAID’s (Nonsteroidal anti-inflammatory drugs) to reduce inflammation. Also, it is critical to ice regularly for 10 to 15 minutes or use an ice cup directly on the area for 5 minutes multiple times per day. Cortisone injections are not suggested because it has the risk of causing degenerative changes to the patellar tendon.
Bracing or strapping is good idea to reduce tension on the bone where the tendon is pulling from. A brace such as an infrapatellar strap is suggested. If you are a basketball or volleyball player wear a knee pad or donut pad.
If no treatment is done and this lingers, it can last 1 to 2 years. Make sure you understand this is a temporary problem linked to a growth spurt where the bone outgrows the muscle. Minor discomfort is acceptable but pain causing a limp or loss of sleep is not. The enlarged tibial tubercle is permanent.
As said previously, once pain has been reduced, the next phase is learning flexibility exercises, specifically in the quadriceps. Make sure to heat the muscle or warm up before stretching. The stretch should ALWAYS be felt in the body of the muscle NOT at the site of where the tendon attaches to the bone where your pain is located. If atrophy is present, then quadricep strengthening may be indicated as long as the specific exercise is pain free. Make sure to always ice after strengthening exercises or after excessive standing or activity.
Author: Avi Bregman, PT, MPT