Gonarthrosis is the medical term for osteoarthritis of the knee joint, a common degenerative condition. This progressive disorder involves the breakdown of cartilage within the knee, which acts as a natural cushion between the bones. Gonarthrosis significantly impacts a person’s quality of life, causing persistent pain, chronic inflammation, and reduced joint mobility.
The Mechanics of Gonarthrosis and Contributing Factors
The mechanics of gonarthrosis involve the deterioration of articular cartilage, the smooth tissue covering the ends of the femur and tibia. This protective layer becomes frayed and thinned, leading to a loss of joint space and allowing the underlying bones to rub against one another. The body attempts to stabilize the joint by forming small, bony projections called osteophytes, which limit motion.
Several factors accelerate this wear-and-tear process. Advancing age is a primary factor, as the body’s ability to repair cartilage diminishes. Excess body weight creates chronic mechanical loading, increasing stress on the joint surfaces during activities. Previous knee injuries, such as meniscus tears, ligament damage, or fractures, can destabilize the joint and accelerate cartilage breakdown. Genetic predisposition and congenital malalignment of the leg, such as bow legs or knock knees, can also unevenly distribute weight and concentrate pressure.
Identifying the Symptoms and Diagnostic Methods
The physical manifestations of gonarthrosis typically develop gradually, linked to the degree of cartilage loss. A hallmark symptom is localized pain that intensifies with movement and subsides with rest. Patients commonly experience joint stiffness, particularly after periods of inactivity, such as in the morning or after sitting.
Another frequent complaint is crepitus, a grinding, clicking, or cracking sensation during knee movement. In advanced cases, the joint may occasionally “lock” or feel unstable, leading to a sensation of the knee “giving way.” Diagnosis is confirmed through a physical examination and diagnostic imaging.
During the physical examination, the doctor assesses the knee’s range of motion, checks for tenderness, and observes for swelling. X-rays are the most common imaging tool, as they clearly show bone changes. These images reveal characteristic signs of gonarthrosis, including joint space narrowing due to cartilage loss and the presence of osteophytes. The extent of damage seen on X-rays is often graded using standardized systems to guide treatment.
Primary Non-Surgical Treatment Approaches
Initial management of gonarthrosis focuses on reducing pain and improving function. Lifestyle modifications are central, particularly weight management, which is highly effective because it directly reduces the load placed on the knee joint. Low-impact exercises, such as swimming, walking, or cycling, help maintain fitness and muscle strength without stressing the joint surfaces.
Physical therapy strengthens the muscles surrounding the knee, especially the quadriceps and hamstrings. Strengthening the quadriceps is important because it enhances joint stability and acts as a dynamic shock absorber, reducing stress on the damaged cartilage. Therapeutic exercise also helps preserve or increase the range of motion and overall physical function.
Medications manage pain and inflammation, with nonsteroidal anti-inflammatory drugs (NSAIDs) being a common option, available as oral tablets or topical creams. Localized injection therapies are used for individuals who do not respond adequately to oral medication.
Intra-articular injections typically involve two main types: corticosteroids and viscosupplementation. Corticosteroid injections provide potent anti-inflammatory effects for temporary, short-term relief from acute pain flares. Viscosupplementation involves injecting a gel-like substance containing hyaluronic acid directly into the joint space. This supplemental injection helps restore lubrication and improve the fluid’s shock-absorbing properties.
Surgical Interventions for Advanced Joint Damage
Surgery is reserved for cases where non-surgical treatments have failed.
Arthroscopy
Arthroscopy is a minimally invasive procedure used to remove loose fragments of cartilage or bone. However, for advanced, widespread gonarthrosis, arthroscopy is generally not considered a long-term solution.
Osteotomy
An osteotomy involves cutting and reshaping the bone, typically the tibia, to realign the leg. This surgery is performed primarily on younger patients with disease concentrated on one side of the joint. The goal is to shift weight-bearing forces to the healthier compartment, preserving the natural joint and delaying the need for total replacement.
Total Knee Arthroplasty (TKA)
The definitive surgical treatment for end-stage gonarthrosis is Total Knee Arthroplasty (TKA), or total knee replacement. During TKA, the damaged cartilage and bone surfaces are removed and replaced with prosthetic components made of metal and polyethylene plastic. A Partial Knee Arthroplasty may be performed if the damage is confined to only one section of the knee, resulting in a smaller incision and quicker recovery.