What is a Hardware Block?
Hardware blocks explained by Denver, Golden, Aurora, Boulder, Broomfield, Jefferson, and Littleton Colorado’s top pain doctors
A leading use of healthcare consultation is to seek treatment for pain associated with spinal disorders. Spine problems, particularly those that may require surgical intervention, are associated with advancing age. Evidence suggests that over 300,000 spinal fusions—a common type of back surgery—are carried out in the U.S. per year. Spinal fusion is a procedure that joins one or more pairs of vertebrae (spinal bones) together. It is done to prevent movement of damaged vertebrae, which is associated with chronic pain. This instability of the spine may be caused by any injury or disease that degrades normal spinal conformation.
Spinal fusion also alleviates stenosis, which is a painful compression of the spinal cord caused by the build-up of scar tissue or other material on the interior surfaces of vertebrae. Many fusion surgeries are also performed to treat degenerations of spinal tissue. In the course of a spinal fusion, items of hardware (i.e. surgical devices) are implanted into the spine in order to maintain its normal structure until the biological component of the fusion takes effect. These can include screws, clamps, or bone grafts. Hardware can cause pain by mechanical interaction with spinal nerves or by stimulating an immune response that includes inflammation. Inflammation is also a cause of chronic pain.
A hardware block is a minimally invasive procedure that can treat chronic pain that arises as a consequence of a fusion surgery. Many post-fusion patients find chronic pain is a reaction to the hardware implanted in the course of their surgeries. A hardware block can also act as a diagnostic tool in eliminating this possibility while locating the source of pain. If hardware-related pain is detected, blocks or other treatment options can then be used to manage this condition.
How is a Hardware Block Performed?
A hardware block typically takes an hour or less to perform. The patient is asked to assume a position that will allow easy access to the area of the spine affected. The physician will anesthetize the area of skin over the area where the hardware has been implanted and inject a nerve block through it. Nerve blocks contain local anesthetics such as lidocaine that effectively block pain when injected into the spine. Nerve blocks are not associated with high risks of pain or discomfort from the injection.
When the procedure is complete, the patient is moved to a recovery area and monitored for a time. If the patient reports significant pain relief, this indicates a high probability that the hardware is the source of pain. If the pain instead persists, it is most likely to be related to another underlying condition, and the hardware is not provoking a noxious reaction.
The patient may be advised to restrict movement, and to rest for the 24 hours following a hardware block. Some complications are associated with hardware block. These are rare, but may include infection, tenderness around the injected area, dizziness, nausea, hematoma, headache, local anesthetic side-effects, and allergic reaction. Side effects of anesthetics include chest discomfort, cardiac anomalies such as arrhythmia, and temporary neurological events, such as a headache. If any of these are experienced following a hardware block, medical attention should be sought.
Conditions Related to Hardware Block Treatment
Hardware blocks are associated with relief from chronic pain caused by surgical implantations in the course of spinal fusion procedures. They are also effective in diagnosing hardware-related pain. Hardware blocks allow assessment of the outcomes of fusion surgeries, and whether or not instrumentations are the cause of a patient’s pain.
Hardware blocks are a non-surgical, minimally invasive procedure associated with relief from chronic pain following spinal fusion surgery. Constant pain is often a reaction to the hardware or surgical devices/instruments implanted in the course of fusions to restore spinal integrity. Hardware blocks are injections of nerve-blocking compounds into the patient’s spine in areas where instruments have been placed. They can also be used to diagnose surgical hardware-related pain. If this is found to be the source of pain, further blocks or other treatments can be used to manage it in the future.
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- Department of Medicine, University of Mississippi Medical Center, Jackson.
- Requests for reprints should be addressed to Richard D. deShazo, MD, Department of Medicine, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS 39216.