Focal osteochondral and cartilage defects of the knee are increasingly recognized in physically active adults and represent an important precursor to early osteoarthritis. Conventional conservative treatments frequently fail to restore function, while surgical options such as microfracture demonstrate variable durability. Platelet-rich plasma (PRP) and mesenchymal stem cell–based therapies have therefore emerged as biologic strategies aimed at joint preservation.

We report the case of a 42-year-old physically active male who presented with persistent anterior and lateral knee pain, weakness, and functional limitation following repetitive snowboarding jumps without direct traumatic impact. Serial magnetic resonance imaging demonstrated progression of tibial cartilage fissuring, osteochondral defect formation, lateral tibiofemoral full-thickness cartilage degeneration, and associated synovial changes. The patient failed to improve with rehabilitation, corticosteroid injection, and standard-concentration PRP. Arthroscopic microfracture was recommended; however, the patient elected to proceed with a series of high-concentration leukocyte-poor PRP injections combined with soluble hyaluronic acid. Three treatment sessions administered over four months resulted in gradual clinical improvement, restoration of quadriceps strength and knee stability, and interval MRI evidence of osteochondral defect healing with early cartilage infilling.

This case illustrates the potential role of repetitive high-concentration PRP combined with hyaluronic acid as a joint- preserving option in carefully selected patients with focal cartilage injury, demonstrating both symptomatic improvement and radiologic healing of osteochondral pathology with concomitant cartilage repair. Randomized controlled trials are warranted to validate these findings.