What Foot Pain?
Foot Pain Explained by Las Vegas, Summerlin, and Henderson Nevada’s Top Pain Doctors
The feet are an unarguably important part of the body. Pain felt in them can have a significant effect on function and movement. Foot pain has a variety of sources, including injury, arthritis, and age. It can result from damage to the muscles, bones, or joints in the feet. Pain can be experienced while walking or moving the feet or toes.
Causes of Foot Pain
The nerves that control sensation in the feet are located in the lumbar (lower back) or sacral (tailbone) region. If these nerves are injured or inflamed, the result is pain in the hips or lower extremities. This can be caused by a number of factors. Injury to the lower back, hips, or legs is among these. Complex regional pain syndrome is a condition that can affect the entire lower extremity, including the feet. Some cancers or cancer treatments can also cause pain in these areas, as they can cause damage to spinal nerves leading to the feet. Spinal surgery on the lower back can also cause inadvertent nerve damage and this can manifest as foot pain.
Other sources of foot pain are mechanical damage simply from prolonged standing or wearing tight, high heeled, or unsupportive shoes. Athletic activity and carrying heavy weights may also be factors. Some genetic diseases, such as Charcot-Marie-Tooth syndrome, can cause deformities in the feet, resulting in pain and in some cases an inability to walk over time. Inflammation is also associated with chronic pain, and diseases in which inflammatory molecules are released into joints or tissues, such as arthritis, are also a source of foot pain.
Treatments for Foot Pain
A first line of treatment for this type of pain is conventional painkillers, administered orally or intravenously. Opioids are often prescribed to cancer patients to treat pain, and to patients after a failed back surgery. These are well-known drugs such as morphine and fentanyl. They block pain receptors that are found in the spinal cord. They do, however, have drawbacks as a treatment option due to their high addictive indexes. There are various alternatives to opioids that also act to stop pain signaling in the spinal nerves affected in hip and foot pain.
Sacral or lumbar nerve blocks are injections of anesthetic medications (e.g lidocaine or bupivacaine) into the nerves affected. These injections also often contain steroids to treat the inflammation that is often a source of pain. The risks of these procedures are nerve damage and inadvertent injection into a blood vessel or into the wrong area of the spine. This can cause numbness and paralysis in severe cases. Temporary complications such as headache are common with lumbar injections.
Another nerve-blocking technique is radiofrequency ablation. In this procedure, the skin and tissue over the nerve is numbed with local anesthetic and a probe is inserted until it comes into close proximity to it. The probe will then apply electro-thermal energy to the nerve, destroying small parts of the nerve responsible for transmitting pain signals. This will not prevent its normal functions (i.e. its sensory signals). In some isolated cases, this can occur or inadvertently create problems with movement. Other risks of ablation are infections at the probe insertion site, failure of the procedure, bleeding, and discomfort. The procedure can achieve several months of pain relief if successful.
Another option to relieve chronic pain may be the implantation in the lumbar region of a spinal cord stimulator (SCS), which causes interference to the pain signaling from its location near the spinal nerve involved in sending it. SCS is associated with risks of spinal scarring, which can cause pain of itself, and inadvertent nerve damage. Other risks include bleeding and infection of the insertion site, and inadvertent amplification of pain responses. They are effective in many cases, and are increasingly popular in lower extremity pain control.
Foot pain can be discomfiting and debilitating, as it obviously can adversely affect day-to-day movement and function. These types of pain can have many sources, including foot injury, occupational hazards such as prolonged standing, and genetic diseases. Pain in the lower extremities is also associated with inflammatory conditions including arthritis. As pain signals are controlled by major spinal nerves, treatments for chronic pain can be directed at them specifically. These treatments are opioids, spinal nerve block, radiofrequency ablation, or spinal cord stimulation.
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