Osgood-Schlatter Disease (OSD) is a common cause of knee pain in adolescents experiencing rapid growth. The condition involves inflammation of the patellar tendon where it attaches to the tibial tuberosity, the bony bump just below the kneecap. This area of the shinbone contains a growth plate susceptible to injury from repetitive stress. While OSD is generally self-limiting and resolves once skeletal maturity is reached, a significant number of people experience persistent symptoms into adulthood. The key distinction for adults is whether symptoms represent a new onset or the continuation of problems that began during youth.
Understanding Osgood-Schlatter Disease
OSD is a traction apophysitis, defined as inflammation and microtrauma where a strong tendon pulls on a vulnerable growth center. The patellar tendon connects the large quadriceps muscle to the tibial tuberosity, which is softer cartilage during adolescence. Rapid bone growth during puberty often causes bones to lengthen faster than surrounding muscles and tendons can stretch. This imbalance increases tension on the patellar tendon during physical activities like running, jumping, and squatting. Repetitive pulling causes inflammation, resulting in pain, swelling, and tenderness directly over the bony prominence below the knee, but the condition generally resolves when the growth plate fuses into solid bone.
Why Symptoms Persist in Adulthood
True, new-onset OSD in a skeletally mature adult is extremely rare because the growth plates have closed and hardened into solid bone. However, symptoms that began in adolescence persist in approximately 10% of patients, leading to chronic knee pain. The adult pathology is a residual effect of trauma sustained during youth, not a problem with the growth plate itself. The most common anatomical reason for chronic adult pain is the formation of a residual bone fragment, known as an ossicle, at the patellar tendon attachment site. This ossicle is a piece of the tibial tuberosity pulled away during adolescence that never properly fused, causing mechanical irritation that often leads to secondary conditions like chronic patellar tendinitis or bursitis. The prominent, irregular bump can also cause chronic friction and inflammation in the overlying pre-tibial bursa, especially when kneeling.
Treatment Options for Skeletally Mature Patients
Managing chronic OSD symptoms in adults differs from the adolescent approach, which focuses on rest and waiting for skeletal maturity. Initial treatment for adults remains conservative, centered on reducing localized inflammation and improving knee joint biomechanics. This includes a targeted physical therapy program designed to enhance the flexibility of the quadriceps and hamstrings, reducing persistent tension on the tibial tuberosity. Activity modification and anti-inflammatory medications help manage flare-ups of pain and swelling. In select cases, advanced non-operative treatments, such as autologous-conditioned plasma injections, may be considered for refractory pain, though corticosteroid injections are generally avoided due to tissue damage risk.
Surgical Intervention
If conservative measures fail to provide sufficient relief, surgical intervention may be necessary, particularly when a painful ossicle is confirmed as the source of chronic pain. The most common procedure is ossicle excision, which involves the surgical removal of the residual bone fragment. Minimally invasive techniques, such as bursoscopic ossicle excision, can offer a faster post-operative recovery. In rare instances, a subtotal tibial tuberosity reduction may be performed to smooth the remaining bony prominence.