Knee and hip osteoarthritis (OA) are two of the leading causes of disability globally. Knee OA is characterized by gradual degeneration of articular cartilage, leading to pain, stiffness, and functional limitations. Patients older than 50 years typically present with knee OA, but it can manifest earlier, particularly following traumatic knee injuries. Symptoms include pain, effusion, stiffness, and reduced range of motion. Radiographs commonly are used to confirm a diagnosis of knee OA. Nonsurgical management options include weight loss, lifestyle interventions, orthotic and assistive devices, pain medications (eg, nonsteroidal anti-inflammatory drugs, acetaminophen), and intra-articular injections. The main injectable treatments are corticosteroids, platelet-rich plasma, and hyaluronic acid. These are used as adjunctive therapies for knee OA. It is essential to differentiate between knee and hip OA and understand differences in patient characteristics, treatment approaches, and outcomes. Knee OA can be successfully managed with nonsurgical treatments. Many patients with knee OA can achieve pain relief and improved function without surgery. In contrast, for hip OA there is no evidence that delaying total hip arthroplasty is beneficial. Total hip arthroplasty is considered one of the most effective orthopedic procedures and typically results in pain relief and restoration of joint function in patients with hip OA.

Case 1. GH is a 57-year-old patient with history of coronary artery disease, hypertension, and type 2 diabetes who presents with pain and stiffness in the left knee. The history indicates that he tore the anterior cruciate ligament in a snow skiing accident when he was a teenager. GH says his knee symptoms have slowly worsened over the past decade. He says his knee function is better overall with regular physical activity, but more intense exercise and activities performed on uneven ground, such as backpacking, usually result in increased pain and swelling. He says ibuprofen helps but wonders about the safety of its long-term use.