Osgood-Schlatter Disease (OSD) is a common cause of knee pain primarily affecting active children and adolescents. It involves irritation and inflammation where the patellar tendon connects to the shinbone, known as the tibial tubercle. Since OSD is tied to skeletal growth, true new-onset OSD cannot occur in a fully grown adult. However, a significant minority of individuals experience residual symptoms or pain that persists years after their growth plates have closed. This ongoing discomfort is a direct consequence of the condition they experienced during their youth.
OSD’s Origin: Why It Is a Pediatric Condition
Osgood-Schlatter Disease is classified as a traction apophysitis, which is an inflammation of a growth plate where a tendon attaches to the bone. The condition is strictly limited to the years of skeletal immaturity because it relies on the presence of the open growth plate (apophysis) at the tibial tubercle. This area is made of cartilage, which is significantly softer and more vulnerable to stress than mature bone.
The powerful quadriceps muscles connect to the kneecap and then via the patellar tendon to the tibial tubercle. Repetitive, forceful contractions, common in sports involving running and jumping, transmit strong pulling forces to this immature cartilage site. This repeated traction causes microtrauma, inflammation, and pain at the attachment point. OSD typically coincides with a child’s growth spurt, when bones lengthen rapidly and muscles may become relatively tighter, increasing strain on the vulnerable growth plate.
The Transition to Adulthood: When Symptoms Typically End
The self-limiting nature of OSD is directly linked to skeletal maturity. The growth plate, the site of irritation, is composed of cartilage until the end of adolescence. Symptoms usually resolve completely once the growth plate at the tibial tubercle fuses, or ossifies, into solid bone. This fusion creates a strong, stable bony attachment site that can withstand the intense pulling forces of the patellar tendon. For the majority of people who had OSD, the pain and inflammation vanish entirely upon reaching skeletal maturity, usually around the ages of 14 to 18.
Symptomatic Residual OSD in Adults
While the original OSD injury cannot recur, symptomatic residual OSD affects adults who had the disease in their youth. This adult pain results from permanent anatomical changes left behind after the growth plate closed. The most common cause of persistent pain is the formation of an ossicle, a small, non-united fragment of bone. This ossicle fragmented during adolescence but failed to merge with the shinbone when the growth plate fused.
Remaining embedded within the patellar tendon, the ossicle can become painful years later due to chronic irritation or direct pressure. Activities like kneeling commonly aggravate the localized tenderness and swelling. Estimates suggest that approximately 10% of people who had OSD as children continue to experience some symptoms into their adult years.
Management Options for Adult Residual Symptoms
Treatment for symptomatic residual OSD focuses on alleviating pain caused by the persistent bony prominence or ossicle. Initial management begins with non-surgical, conservative methods aimed at reducing inflammation and improving knee function. These approaches often include physical therapy to stretch tight muscles and strengthen surrounding musculature, such as the quadriceps and hamstrings. Pain relief is commonly achieved through non-steroidal anti-inflammatory drugs (NSAIDs) and by modifying activities to avoid direct pressure on the painful bump.
When conservative treatment fails after six to twelve months, surgical intervention may be considered. The procedure involves excising, or removing, the painful ossicle and any surrounding inflamed tissue. This operation is reserved for cases of persistent, debilitating pain, and a high success rate is reported for symptom resolution.