People living with multiple sclerosis (MS) often experience impaired balance, difficulty walking, mild to severe muscle weakness, and sensory disturbances. Each of these symptoms can put extra strain on the body as patients struggle to stay mobile and active.
Osteoarthritis (OA) is the most common joint disorder that causes symptoms in the United States. It affects approximately 10 percent of men and 13 percent of women aged 60 years or older.
Pain and disability caused by osteoarthritis can make climbing stairs and walking difficult. Increased risk factors include older age, female gender, obesity, knee injury, repetitive use of joints, muscle weakness, and joint looseness. Radiographic signs of OA include osteophytes (also called bone spurs), joint space narrowing, and breakdown of cartilage.
Although OA is generally considered to be a “wear and tear” condition affecting older adults, it can also affect individuals in their 40s and 50s. I was first diagnosed with knee osteoarthritis in my early 40s, several years after being diagnosed with MS in my mid-30s. My case of OA is tricompartmental, meaning that it affects each of three joint areas where the thigh bone and lower leg come together and behind the kneecap. Eventually I will need total knee replacement on both my left and right knees.
Do MS symptoms lead to osteoarthritis?
One of the more complex risk factors for knee OA is muscle weakness, particularly in the quadriceps. MS can be associated with weak thigh muscles. Researchers examining potential associations between MS and osteoarthritis hypothesized that the knee joint in people with MS might be more greatly affected due to problems with balance and muscle weakness and may result in earlier joint degeneration.
To test this theory, researchers used ultrasound to investigate whether there is a correlation between the breakdown of femoral cartilage — the cartilage that covers the end of the thigh bone — and MS-related disease parameters.
Researchers recruited 79 people with MS (aged 18-50, able to walk with or without assistance, and no history of knee injury or rheumatic disease) and 60 healthy age- and sex-matched controls. Several outcomes, including disability, physical functioning, pain, and balance, were measured in the study. Ultrasound was used to evaluate the sharpness, clarity, and thickness of cartilage.
Scores for pain, stiffness, and physical function were significantly worse in the MS group compared to those of the control group. Members of the MS group had more impaired balance. Researchers found that the femoral cartilages of patients with MS were significantly more degenerated compared with healthy controls. Also, members of the MS group had more effusion — swelling or “water on the knee” — than did controls. Results of the study were published in the Journal of Rehabilitation Medicine.
Overall, this study demonstrated that patients with MS may have more rapid cartilage degeneration and increased effusion in their knees compared with healthy controls and that the intra-articular changes may be visualized with ultrasonography. However, the degeneration of cartilage was not associated with disease-related parameters. Further studies investigating the effect of spasticity, muscle strength, and sensory deficits are needed to clarify the impact of MS on knee degeneration.
How do you treat osteoarthritis?
According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), common treatments for osteoarthritis include:
- Medicines to reduce pain, such as aspirin and acetaminophen;
- Medicines to reduce swelling and inflammation, such as ibuprofen and nonsteroidal anti-inflammatory drugs (NSAIDs);
- Exercises to improve movement and strength; and
- Weight loss.
What types of exercise are best for someone with knee problems?
Three types of exercise are best for people with arthritis:
- Range-of-motion exercises to help maintain or increase flexibility and relieve stiffness in the knee;
- Strengthening exercises to help maintain or increase muscle strength that will in turn support and protect joints with arthritis; and
- Aerobic or endurance exercises to improve heart function and blood circulation, help with weight control, and reduce swelling in some joints.
For my own knee osteoarthritis, I have received corticosteroid injections, physical therapy, and hyaluronate viscosupplementation injections which are designed to help improve lubrication and cushioning inside the joint. I also ride my bicycle for exercise and follow strengthening and flexibility exercises prescribed by my physical therapist.
Researchers do not have clear answers as to why people with MS may have earlier and more significant cartilage degeneration compared to healthy individuals. However, more recent studies have indicated that the immune system plays a role in the development of OA. I look forward to researchers continuing to look for answers.
Eroglu S, Inal EE, et al. Ultrasound detection of knee joint degeneration in patients with multiple sclerosis. J Rehabil Med. 2016;48(7):604-8. doi: 10.2340/16501977-2099.
Orlowsky EW, Kraus VB. The Role of Innate Immunity in Osteoarthritis: When Our First Line of Defense Goes on the Offensive. The Journal of Rheumatology. 2015;42(3):363-371. doi:10.3899/jrheum.140382.
Zhang Y, Jordan JM. Epidemiology of Osteoarthritis. Clinics in geriatric medicine. 2010;26(3):355-369. doi:10.1016/j.cger.2010.03.001.