Ask Dr. Hildahl: How Is Carpal Tunnel Syndrome Identified?
Hand specialist Dr. Blake Hildahl explains how symptoms aid diagnosis of carpal tunnel syndrome.
We depend on healthy wrists for a multitude of daily tasks. When persistent numbness and tingling make it painful to use our hands, we could be experiencing symptoms of carpal tunnel syndrome. The carpal tunnel is a narrow passageway in the wrist. The median nerve runs through this passageway along with the tendons that bend the fingers. Carpal tunnel syndrome is caused when inflammation narrows the passageway, compressing the median nerve. Hand specialist Dr. Blake Hildahl shares a helpful metaphor to explain this painful condition.
Diagnosing carpal tunnel syndrome
“We think about the wrist when we talk about carpal tunnel,” says Dr. Hildahl. “People may not realize that the median nerve comes down from the spine, and runs through the arm into the fingertips. My medical school mentor used a garden hose analogy to describe how compression of the nerve happens. I thought it made a ton of sense, so now I use this analogy with my patients.”
Dr. Hildahl tells his patients to think of their median nerve as a garden hose. “Imagine the hose coming out of your neck and going down to your fingertips and back. It brings water, or nerve sensation, along that path from brain to fingertips. At any point along the path, from spine to wrist, someone could be stepping on the garden hose—in effect, compressing the nerve. Based on the severity of the compression—or kinking of the hose, the hand and the brain are no longer able to send signals back and forth, just like a hose is unable to send water.”
When the compression occurs at the wrist, it’s called carpal tunnel syndrome. Typically, carpal tunnel affects the thumb side of the hand. Some people also experience shooting pain in their arm.
Complex carpal tunnel syndrome
Carpal tunnel syndrome is not always confined to a wrist compression. “A garden hose can be kinked in multiple places, and so can the median nerve,” explains Dr. Hildahl. “This is called a double crush. Double crush commonly occurs when the nerve is crushed in the spine as well as at the wrist. Think of it as a hose that is pinched in two spots. When symptomatic pain extends farther up the forearm, that is a clue that tells me there may be more than one compression. I also look at my patient’s legs and gait, because a spine compression can cause trouble with walking.”
When nerve conditions are suspected, Dr. Hildahl uses an electromyogram (EMG) test to detect the source of compression. Patients with a median nerve compression and also spine compression may be sent to the spine team. “Our spine colleagues can treat the crush in the neck,” he explains. “The goal is to accurately identify the source of the nerve pressure and relieve it, so you can return to normal activity.”
The risk of ignoring carpal tunnel syndrome symptoms
“Sometimes, if a garden hose has been pinched for too long, the hose won’t reshape when you remove the pressure,” says Dr. Hildahl. “If you’ve been ignoring carpal tunnel symptoms, your nerve may have compression that is not reversible. We are usually talking about symptoms that have gone on for years without being addressed. Sustained pressure on the nerve will eventually cause weakness in hand muscles. It’s to your advantage to consult a hand specialist when symptoms arise. Once the hand muscles are affected, we can’t always completely reverse the damage.”
“My job as a physician is to relieve the pressure or compression around the nerve,” says Dr. Hildahl. “There are a lot of structures in the wrist that are channeled through a small area. Here at Summit, we have a range of treatment options to ease the pressure, relieve the pain, and get you back to full hand function.”
Summit Orthopedics provides personalized hand and wrist expertise
The function of our hands is integrated through our wrists and arms to our shoulders; a problem anywhere along our arm may have a significant impact on hand function and quality of life. If you experience an injury or uncomfortable symptoms, our fellowship-trained hand and wrist surgeons are here to help. Summit physicians receive the highest levels of training and exclusively provide individualized care for conditions of the hand, wrist, and elbow.
Summit has convenient locations across the Minneapolis-St. Paul metro area, serving Minnesota and western Wisconsin. We have state-of-the-art centers for comprehensive orthopedic care in Eagan, MN, Vadnais Heights, MN, and Woodbury, MN, as well as additional community clinics throughout the metro and southern Minnesota.
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