What is Knee Pain?
For the amount of force it handles, it is not surprising that knee pain is the most common joint ailment. Chances are someone from a local sports team is currently recovering from a knee injury, but knee pain isn’t just a problem for athletes. Almost 20% of adults report knee pain annually—more than double any other joint (Adults Reporting Joint Pain or Stiffness in the Past 30 Days )1. From mild swelling and discomfort, to structural bone or ligament damage, knee pain consistently proves to be one of the most inconvenient, worrisome ailments. Proper diagnosis is paramount when treating knee problems. Continued activity on a structurally damaged can permanently damage the joint and vastly increase recovery time.
The knee’s primary function — to bend and extend — is critical to walking. Made up of an inner, outer and lateral compartment, the knee joint connects the femur and tibia to the kneecap. The joint is surrounded by ligaments, which strap the inside and outside of patella to provide stability. The meniscus is a cartilage pad, which separates the kneecap from both joints. Fluid-filled bursa sacs surround the entire joint to reduce friction and promote smooth motion. Large thigh muscles move the knee. (Knee Pain)2. With aging, this complicated joint is susceptible to degeneration. Osteoarthritis, which is sometimes known as degenerative arthritis, is one of the most common causes of knee pain. The wear and tear of years of use can cause cartilage in the knee to deteriorate. The result is bone-on-bone contact between joints, which can make movement uncomfortable. More debilitating forms of knee degenerative pain include rheumatoid arthritis and gout, which build up uncomfortable material in joints. Osgood-Schlatter syndrome also results in a disruptive build-up but occurs more commonly in athletes(Staff)3. A combination of heat and ice is usually recommended for these progressive ailments, along with physical therapy. Ice can help alleviate tissue build-up and swelling, and stretching takes pressure off the joint.
More serious knee problems involve structural damage, which may be more painful and more involved solutions. Anterior crucial ligament tears are the most common form of structural knee damage. Most commonly a sports injury, ACL tears usually occur from a knee being traumatically twisted. This injury sometimes induces a “popping” sensation upon initial trauma. Meniscus tears are another common structural knee injury. When the cartilage between joints is torn, it can cause swelling and limit motion. In some cases, the torn piece of cartilage can flip inside the joint, causing the knee to lock. Some ligaments sprains can be treated with rest and anti-inflammatory remedies but tears usually require surgery. Ligament surgery takes months of rest and exercise to build up strength in the joint. Meniscus tears require a less invasive arthroscopic surgery and patients usually recover in 4-6 weeks. (Knee Arthriscopic Surgery)4
Like any other bone, knee pain can be the result of a simple bruise. The complicated nature of this joint and its importance to daily life make it wise to not assume the pain will dissipate, however. When caught early, knee discomfort can be sorted out with exercises and slight life-style changes, such as running on a treadmill instead of hard pavement.
Types of Knee Pain
The main movement of the knee is bending (flexion) and straightening (extension). The knee is also capable of twisting, which is what accounts for many traumatic injuries to the ligaments of the knee. Some symptoms of this type of injury include a “popping” sound, immediate inability to bear weight on the affected limb, or a sensation that the knee is going to “give way.” These types of injuries typically warrant surgical referral. Twisting can also cause injury to the tendons (tendonitis) or the meniscus. Both of these types of injuries can cause pain and swelling, as well as difficulty straightening the leg. Another main cause of knee pain is degeneration.
Osteoarthritis of the knee is considered a “wear and tear” condition in which the cartilage in the knee degenerates as we age. When osteoarthritis becomes severe, there is no more (or very little) cartilaginous cushion between the knee bones, which can cause significant pain. Chondromalacia patella is also a type of degeneration, and generally means that there is damage to the cartilage beneath the kneecap.
Knee Pain Treatment
The most important aspect of treating knee pain is establishing a diagnosis, usually by way of knee MRI. There are several injections that may help knee pain. One of the most common injections is a corticosteroid injection directly into the knee joint. This type of injection reduces inflammation and pain. Viscosupplementation (Orthovisc, Synvisc) provides lubrication to the knee joint for persons with degenerative conditions such as osteoarthritis.
The most common type of nerve block for knee pain is called a saphenous nerve block, which can provide relief to persons with many types of knee pain, including people who have undergone total knee replacement. Other very helpful treatment modalities for knee pain include chiropractic therapy, gait analysis, bracing, and TENS unit application. Physical therapy can help to strengthen the muscles surrounding the knee joint, improving its stability. Utilizing ice on the knee can help decrease pain and swelling. Anti-inflammatory medications (ibuprofen, naproxen sodium, Celebrex) are the mainstay of treatment for people with knee pain, however other types of medication may be helpful as well. If a person is experiencing an acute-type injury of the knee, an orthopedic surgery referral is typically warranted.
- Adults Reporting Joint Pain or Stiffness in the Past 30 Days . (n.d.). Retrieved July 11, 2011, from Centers for Disease Control and Prevention : www.cdc.gov/Features/dsJointPain
- Knee Pain. (n.d.). Retrieved July 11, 2011, from MedicineNet: www.medicinenet.com/knee_pain
- Staff, M. C. (n.d.). Knee Pain: Causes. Retrieved July 11, 2011, from Mayo Clinic.
- Knee Arthriscopic Surgery. (n.d.). Retrieved July 11, 2011 , from Encylopedia of Surgery : www.surgeryencyclopedia.com/Fi-La/Knee-Arthroscopic-Surgery
- Kim, Philip (2004). Advanced Pain Management Techniques: An Overview of Neurostimulation. Retrieved February 16, 2010 from: http://www.medscape.com/viewarticle/473431 Tennent, TD, Birch, NC, and MJ Holmes (et al)(1998).
- Knee Pain and the Infrapatellar Branch of the Saphenous Nerve. Journal of the Royal Society of Medicine 1998;91:573-575.
- The Center for Orthopaedics & Sports Medicine (2003). Knee Joint- Anatomy and Function. Retrieved February 16, 2010 from: http://www.arthroscopy.com/sp05001.htm The Mayo Clinic (2008).
- Knee Pain. Retrieved February 16, 2010 from: http://www.mayoclinic.com/health/knee-pain/DS00555