From the Guidelines
The primary risk factors for knee arthritis include advancing age, obesity, previous knee injuries, repetitive stress on the joints, genetics, and female gender, as supported by the most recent study 1. The risk factors for knee arthritis are multifaceted and can be categorized into patient-level and joint-related factors.
- Advancing age is a significant factor, as cartilage naturally deteriorates over time, with most people developing some degree of arthritis after age 60 1.
- Excess weight places tremendous pressure on knee joints, with each pound of body weight creating four pounds of pressure on the knees during walking 1.
- Previous injuries such as ACL tears, meniscus damage, or fractures significantly increase arthritis risk by altering joint mechanics and causing premature cartilage wear 1.
- Occupations or activities requiring repetitive knee bending, kneeling, or heavy lifting accelerate joint degeneration, as evidenced by strong and moderate levels of evidence for increased risk of knee OA in men and women engaged in these activities 1.
- Genetic predisposition plays a role, with family history increasing risk, particularly for osteoarthritis, and women, especially after menopause, develop arthritis more frequently than men, likely due to hormonal factors and anatomical differences 1. Other contributing factors include certain metabolic conditions like diabetes, joint malalignment issues such as bowlegs or knock-knees, and inflammatory conditions like rheumatoid arthritis, which can increase the risk of developing knee arthritis 1. Understanding these risk factors helps identify individuals who may benefit from preventive strategies like weight management, proper exercise techniques, and early intervention for knee injuries, ultimately reducing the morbidity, mortality, and improving the quality of life for those affected by knee arthritis.
From the Research
Risk Factors for Knee Arthritis
- Age is a common risk factor for knee osteoarthritis (OA), with incidence rising by increasing average age of general population 2
- Weight is also a significant risk factor, with being overweight (pooled OR 1.98,95% CI 1.57-2.20) and obesity (pooled OR 2.66,95% CI 2.15-3.28) associated with onset of knee pain 3
- Trauma to joint due to repeating movements, such as squatting and kneeling, is a risk factor for knee OA 2
- Previous knee injury is a significant risk factor, with a pooled OR of 2.83 (95% CI 1.91-4.19) 3 and 3.02 (95% CI 1.93,4.71) 4
- Female gender is also a risk factor, with a pooled OR of 1.68 (95% CI 1.37-2.07) 3
- High bone mineral density is associated with an increased risk of incident radiographic KOA, with an OR of 1.82 (1.12,2.94) 4
- Occupational physical activity is a modifiable risk factor that contributes to radiographic or symptomatic KOA 4
Modifiable Risk Factors
- Overweight/obesity accounts for 14% of incident radiographic KOA and is a key target for prevention of development of knee pain 3, 4
- Previous knee injury accounts for 5.1% of cases of new onset of knee pain 3
- Novel strategies addressing known modifiable risk factors, including overweight/obesity, knee injuries, and occupational physical activity, are needed to reduce overall burden of KOA 4