Knee Osteoarthritis: Managing Pain and Preserving Function

What Happens to the Knee in Osteoarthritis

Osteoarthritis (OA) is the most common form of arthritis, affecting an estimated 32.5 million adults in the United States. In the knee, it occurs when the articular cartilage — the smooth, slippery tissue that covers the ends of the bones and allows them to glide against each other — breaks down over time. As cartilage thins and becomes irregular, the joint loses its normal cushioning, bone surfaces begin to contact each other, and the surrounding tissue responds with inflammation, swelling, and bone spur formation.

The result is a knee that is stiff in the morning, painful after activity, prone to swelling with extended use, and increasingly limited in its range of motion. The medial (inner) compartment of the knee is most commonly affected, which can produce a visible bowing of the leg as the joint space narrows asymmetrically.

Osteoarthritis is not simply a consequence of aging. Risk factors include previous knee injury (especially ACL tears or meniscus damage), obesity, family history, malalignment of the knee, and repetitive loading from certain occupational activities.

Non-Surgical Management

The treatment of knee OA is stepwise. Surgery — specifically total knee replacement — is an effective and proven procedure, but it is not the right first step for most patients. A structured non-surgical program addresses pain, function, and quality of life for many years before replacement becomes necessary, if ever.

Exercise and physical therapy form the foundation of conservative management. Strengthening the muscles around the knee — quadriceps, hamstrings, and hip abductors — reduces the load on the joint surface with every step. Low-impact exercise such as cycling and swimming maintains cardiovascular fitness and joint mobility without the impact loading of running. Walking, when tolerated, is also beneficial; activity restriction alone is not a treatment strategy.

Weight management has a direct, quantifiable effect on knee OA symptoms. Each pound of body weight generates approximately three to four pounds of force on the knee during walking. Meaningful weight reduction produces proportional reductions in joint loading and symptom severity.

Corticosteroid injections reduce joint inflammation and provide pain relief measured in weeks to months. They are most effective when combined with physical therapy rather than used in isolation.

Hyaluronic acid (viscosupplementation) injections supplement the synovial fluid that lubricates the joint. Results are variable — some patients experience meaningful symptom relief for six months or longer, others notice little benefit. Viscosupplementation is generally considered when steroid injections are no longer providing adequate duration of relief.

Platelet-rich plasma (PRP) injections use concentrated growth factors derived from the patient's own blood to modulate inflammation and support tissue health. Clinical trial data suggests PRP produces more sustained improvement in pain and function than corticosteroid or hyaluronic acid injections in patients with early to moderate knee OA, with effects lasting up to 12 months.

When Surgery Is Indicated

Total knee replacement is one of the most reliably successful procedures in orthopedics, with published data showing that more than 90 percent of implants remain functional at 15 years. It is appropriate when non-surgical treatment has been adequately tried and symptoms remain severe enough to significantly limit daily life — particularly when pain is present at rest or at night and when walking distance is substantially curtailed.

Partial knee replacement (unicompartmental arthroplasty) is an option for patients whose arthritis is confined to one compartment of the knee. It preserves more native bone and tissue and is associated with faster recovery than total replacement, though not every patient is a candidate.

The timing of surgery is a shared decision between you and your surgeon, informed by the severity of your symptoms, your functional goals, and your overall health.

If you're dealing with knee pain from arthritis, the specialists at Maryland Orthopedic Specialists can help. Call (301) 515-0900 or [schedule an appointment online](https://www.mdorthospecialists.com/contact).