Knee Pain

What are the Most Common Causes of Knee Pain?

Injury is likely the most common cause of knee pain associated with athletes and active persons. There are four ligaments that connect your shinbone to your thighbone. The ACL injury is a rupture in the anterior cruciate ligament, which is one of these four ligaments.

Another common cause of knee pain is a torn meniscus. The meniscus is a tough, hard rubbery cartilage that performs like a shock absorber in the knee joint. It can tear with sudden twisting motions of the knee when bearing weight or simply due to degeneration with aging.

Bursitis of the knee is another common cause of knee pain along with irritation of tendons surrounding the knee. Inflammation of a bursa (fluid-filled sacs cushioning the joints) caused by injury or age. Another cause of knee pain is patellar tendinitis, which is the irritation and inflammation a tendon or tendons. This is also referred to as “runner’s knee”. Age can also be a factor in knee pain as arthritis is common in older persons and affects the joints.

What are Common Symptoms of Knee Pain?

The most common symptoms of knee pain are stiffness and swelling, warm to the touch and reddish in color, weak or unstable, gritty feeling or frequent popping. More severe symptoms may necessitate that you seek medical attention, symptoms such as inability to bear weight, noticeable swelling, if you are unable to fully extend or flex your knee, if you have an obvious deformity in your knee, if you have other symptoms accompanied by fever, or if your knee is unstable or gives out.

For an ACL tear, the most common immediate symptom is a feeling of a “pop” that may also be audible. Meniscal tears may present with clicking, locking or popping. Additionally, a decreased range of motion may result.

Degenerative arthritis may also result in decreased range of motion, pain with weight bearing, and increased pain after periods of inactivity. Some textbooks refer to this as “movie theater syndrome”. Those with arthritis typically have discomfort after getting up from sitting for a period of time, with the analogy being sitting in one place for a couple of hours to watch a movie.

How do Doctors Diagnose this Type of Pain?

An injury is an obvious cause of knee pain, for other factors your Chicago pain doctor may examine your knee by doing a series of tests or they may require x-rays to be taken in order to get a clear image of the joint to see if arthritis is a factor. An MRI may be necessary to determine if a torn ligament is the cause.

There are a series of instability tests that are performed to see if the ACL is injured or the collateral ligaments are unstable. There are also tests to help diagnose a meniscal tear, which is usually correlated with what is seen on the X-rays and MRI.

What are the Most Common Treatment Options for Knee Pain?

Alternative methods and conservative treatments will be the first option to relieve a patient’s knee pain.

• Acupuncture – for arthritis in particular there are now several research studies proving its effectiveness.
• Bracing – patellar sleeves, functional braces, unloaders.
• Cane
• Physical therapy to improve range of motion and relieve pain.
• Heat and ice treatments.
• Massage therapy soft tissue manipulation.
• Ultrasound therapy using high-energy sound waves to improve blood circulation.
• Transcutaneous electric nerve stimulation (TENS units).
• Medications including NSAIDs, Tylenol, short-term Opiates.
• Prescription Pain Creams – very effective and do not enter the bloodstream.
• Steroid Injections (Cortisone)
• Hyaluronic Acid Injections – Synvisc, Orthovisc.
• PRP injections to accelerate healing and repair

Surgery is usually only considered after all options with conservative methods have been exhausted, or found to be ineffective. Knee pain symptoms from a damaged meniscus or ACL may be treated with a minimally invasive arthroscopy.

For more severe cases a partial prosthesis or total knee replacement may be needed for the patient to be pain free. Joints may be made from chrome, titanium or cobalt alloy. Joint replacement of the knee may involve two types of procedures: cemented (uses a bone cement for extra support) or cementless (uses a material allowing for natural growth).

Top 10 Nonoperative Knee Pain Treatments

Osteoarthritis (OA) is the leading reason for functional disability in older adults, and it disables 10% of Americans over the age of 60 years. The most common joint affected by OA is the knee joint. Find out about the top 10 nonoperative knee pain therapies.

RICE

For simple knee sprains and overuse injuries, RICE (rest, ice, compression, elevation) will help. The patient rests the affected leg for several days, applies ice in 20-minute intervals, uses a compression wrap (ACE bandage), and elevates the knee to decrease swelling.

Orthotics and Footwear

To treat knee pain associated with OA with varus deformity, special lateral-wedged insoles are used. Two recent randomized controlled trials found that these orthotics decrease patient consumption of knee pain. Elevated joint load is associated with progression of knee OA, so experts recommend a specially designed flexible, flat shoe for walking.

Knee Bracing

External bracing of the knees alleviates knee pain. Commonly used devices include rest braces, un-loading knee braces, patellar taping, and knee sleeves. Rest braces are made of stiff composite material that is specifically designed for joint immobilization. In a recent study, simple neoprene knees sleeves decreased pain, improved function, and improved quality of light. These are often used for varus malalignment of the knee due to OA progression. Un-loading knee braces can improve balance and stabilize the joint. In addition, patellar taping is done using adhesive, rigid tape that is positioned to the patella. In a large review of studies, patellar taping of the knee produced significant reduction of pain.

Physical Therapy

Many cases of knee pain can be alleviated using physical therapy. Prolonged inactivity of the knee joints can result in deconditioned muscles and periarticular stiffness. Physical therapy exercises improves muscle function and relieves pain. In a longitudinal study involving 2,000 patients, improving knee extensor strength with physical therapy lowered the incidence of symptomatic knee OA. In the Fitness Arthritis and Seniors Trial (FAST), PT improved function, pain, and disability in adults aged 60 years and older.

Oral Medications

Knee pain can often be treated using medications. Commonly prescribed agents include:

• Acetaminophen – Tylenol has both anti-pyretic and analgesic actions, and it is recommended for mild knee OA.
• NSAIDs – Nonsteroidal anti-inflammatory drugs can reduce inflammation, swelling, and joint stiffness. Many studies confirm these agents are effective for knee pain.
• Tramadol – This is an atypical analgesic that is proven in many clinical studies to relieve knee pain.
• Opiates – Narcotic analgesics can be used when other medications do not help. In a large meta-analysis involving over 6,000 patients, opiates were found superior to other medicines for OA pain.

Topical Agents

Topical agents are include topical Capsaicin, topical NSAIDs, lidocaine patches, and Aspercreme. These medications penetrate the skin and work directly at the site of pain. In a recent study, Voltaren gel used for 8 weeks lowered patients’ pain scores by 45%.

Corticosteroid Joint Injections

OA knee pain can be treated using a corticosteroid agent, which is injected into the knee joint. A few studies have shown that corticosteroid knee injections offers long-term effects, but most studies show benefits lasting between 3 and 6 weeks. The doctor first cleans the skin of the knee using an antiseptic, and then inserts the needle into the joint. If excessive fluid is present, the doctor can aspirate it before injecting the medication.

Hyaluronic Acid Joint Injections

Common name brands of hyaluronic acid include Hyalgan, Synvisc, Orthovisc, and Euflexxa. These agents are administered as a series, given weekly for 3-5 weeks, or given once every 3-6 months. Hyaluronic acid mimics normal joint fluid, which is often depleted with knee OA and injury.

Alternative Agents and Nutraceuticals

Herbal and nutritional supplements have been reported to decrease arthritis pain. These agents include methylsulfonylmethane (MSM), s-adenosylmethionine (SAM-e), ginger extracts, and avocado-soybean unsaponifiables (ASUs). Glucosamine is a substance many people take to improve physical function and stiffness. In the glucosamine sulfate unum in die efficacy (GUIDE) trial, researchers compared glucosamine sulfate to acetaminophen and a placebo. They found that glucosamine demonstrated better pain relief than the Tylenol.

Chiropractic Treatment

Chiropractic treatment aims to reduce pain and joint inflammation by using supportive devices, icing the area, and using ultrasound to promote soft tissue healing. Specific chiropractic manipulation techniques are applied to areas of restricted movement in the knee joint, which can improve overall knee function.

Resources

Al-Hakim W, Jaiswal PK, Khan W, & Johnstone D (2012). The Non-Operative Treatment of Anterior Knee Pain. Open Orthop J, 6, 320-326.

Mushtaq S, Choudhary R, & Scanzello CR (2011). Non-surgical treatment of osteoarthritis-related pain in the elderly. Curr Rev Musculoskelet Med, 4(3), 113-122.