3 Causes of Knee Pain That Can Sidetrack You From Exercise

Knee pain is a common complaint among seasoned athletes, regular exercisers, and weekend warriors alike — especially with advancing age. Whether it appears whenever you bear weight, only flares during or after intense activity, or bothers you almost constantly, chronic knee pain can leave you sitting on the sidelines. 

If knee pain is making you less active, our Sports Medicine Oregon team can help.

Here, our board-certified orthopedists explore three top causes of persistent knee pain in active adults and explain how early evaluation and care can provide the relief you need to get back on track with your healthy lifestyle. 

Oh, my aching knee joint! 

Knee pain can stem from age-related degeneration, repetitive stress (overuse), acute injury, or a combination of these causes. Most cases emerge in one of the following ways:

• Slowly over time, such as mild knee pain that first appears at the end of the day, but gradually worsens in intensity and duration over time
• Immediately after trauma, such as right after a sports injury or accidental fall
• Delayed reaction after trauma, or knee pain that begins hours or days after injury 
• Suddenly and without warning, such as significant knee pain that occurs during normal activities for no apparent reason 

Where you feel knee pain depends on the part of the joint that’s injured or damaged. Some problems cause achiness deep inside the joint, while others trigger surface pain that seems to be just above or behind the knee. In some cases, knee pain may radiate around the joint and down your leg. 

Common causes of knee pain

Common knee pain problems include ligament sprains, tendon strain or inflammation, cartilage tears, and arthritis-related damage and inflammation. Three of the most frequent causes of knee pain that can make it hard to stay active are:

1. Patellofemoral pain syndrome

An estimated one in three people who visit the doctor for knee pain have patellofemoral pain syndrome (PFPS), an overuse injury also known as “runner’s knee.” PFPS causes:  

• Dull, aching pain behind or around the kneecap 
• Sharp pain during knee-intensive activities (i.e., squatting)
• Kneecap pain that worsens with exercise or inactivity
• Cracking sound or popping sensation in the knee joint 

Your kneecap (patella) is the bone at the front of your knee that protects the joint and supports key ligaments, muscles, and tendons. With PFPS, something — often repetitive stress from the same movement, or increased joint tension from imbalanced leg muscles — affects how your kneecap moves, irritating the underlying cartilage and causing pain.  

2. Degenerative meniscal tears

Menisci are two rubbery pieces of cartilage situated between the thigh bone (femur) and the shinbone (tibia), on either side of the knee joint. These tough, crescent-shaped discs provide stability, absorb shock, and distribute weight evenly across the joint. 

A split or torn meniscus is a frequent and painful acute knee injury among younger athletes, but it’s also a common degenerative injury among aging adults. With a chronic degenerative meniscal tear, you may initially experience no symptoms at all, followed by: 

• Persistent knee pain
• Knee stiffness and swelling
• Knee weakness and instability
• Joint “catching” or locking 
• Difficulty extending your knee

Degenerative meniscal injuries tend to be more complex, with fraying. They can occur with minimal stress because of age-related wear and weakness; they’re also a common early sign of osteoarthritis (OA) — or degenerative joint disease.

3. Joint degeneration (osteoarthritis)

OA — also known as “wear-and-tear” arthritis or degenerative joint disease — is the most common cause of knee pain in adults older than 50. OA breaks down the smooth cartilage tissue that cushions the ends of your bones within your knee joint, causing:      

• Joint friction and inflammation
• General joint pain and achiness
• Knee stiffness after inactivity
• Instability or knee “buckling”
• Reduced range of joint motion 
• Grinding sensations or sounds

Initially, OA may simply make the affected knee feel stiff and achy. As cartilage loss progresses, however, it can cause considerable pain that limits your mobility and makes daily tasks — including exercise — more challenging. 

Don’t get sidelined by knee pain

One of the most ironic things about knee pain that makes it hard to stay active is that in virtually every case, exercise is a fundamental part of joint rehabilitation. The first step? Seeking an expert evaluation to find out exactly what’s going on with your knee. 

Early care for most knee pain problems centers on physical therapy, or specific exercises and stretches designed to strengthen and balance muscles around the affected knee in order to take some pressure off the joint.   

Even with knee pain problems that ultimately require surgery — like most meniscus tears — exercise and continued movement are key to healing. 

Is knee pain making you less active? We can help. Call or click online to schedule a visit at your nearest Sports Medicine Oregon location in Tigard or Wilsonville, Oregon, today.