What is knee pain?
What causes knee pain?
Injury and degeneration are the main causes of knee pain. The knee is capable of bending (flexion) and straightening (extension), but also capable of twisting, which is what accounts for many traumatic injuries to the ligaments of the knee. A knee injury can affect the ligaments, tendons, or fluid-filled sacs that surround the knee joint, as well as the bones, cartilage, and ligaments that form the joint itself.
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.
Some symptoms of a knee 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. With a degenerative condition, you may experience chronic pain, swelling, and difficulty straightening the leg.
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.
If the patient does not respond to more conservative treatments, neuromodulation through spinal cord stimulation may be considered. Spinal cord stimulation involves placing small electrodes within the epidural space of the spine. The theory behind spinal cord stimulation is that stimulation of the large nerve fibers will inhibit the small nerve fibers, thus blocking the sensation of pain.
The most important aspect of treating knee pain is establishing a diagnosis, usually by way of knee MRI. Once the diagnosis is complete, there are several treatments that can help alleviate pain.
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. Neuropathic medications (gabapentin, Lyrica) are beneficial for persons who have neuropathic pain symptomatology (burning, numbness, “pins and needles”), and opioid medications (hydrocodone, oxycodone) are beneficial for people with acute knee injuries.