The clinical term “Phalen’s Maneuver” refers to a provocative test used in the diagnosis of carpal tunnel syndrome. We also know this as a wrist-flexion test 1. Carpal tunnel syndrome (CTS) refers to a condition that puts pressure on a nerve in your wrist. This condition causes tingling, numbness, and pain in your hand and fingers.
You can often treat it yourself, but it can take months to get better. The other symptoms of carpal tunnel syndrome include an ache or pain in your finger, hand, or arm, numbness in the hands, a weak thump, or difficulties in your gripping. These symptoms usually worse at night and start slowly and go again. To solve this problem, your doctor will suggest Phalen’s maneuver for your recovery.
To diagnose carpal tunnel syndrome and rule out the other causes of hand and wrist pain, your doctor may use a handful of tests. These tests include Phalen’s maneuver, Tinel’s sign, and a two-point discrimination test 2.
During Phalen’s maneuver, your doctor will ask you to press the back of your hands and fingers together with your wrists flexed in completion and your fingers pointed down. You will stay in that position for at least one or two minutes. If your finger develops a tingle or gets numb, then you have carpal tunnel syndrome. Now, we will discuss the mechanism of the Phalen’s maneuver.
Usually, the lumbrical muscle attaches in part to the flexor digitorum profundus tendons. When you flex your wrists, your flexor digitorum profundus contracts in a proximal direction and draws the lumbricals along with it. In some people, the lumbrical muscle dragged into the carpal tunnel with their flexor digitorum profundus contraction. That’s where the Phalen’s maneuver works and moderately increases the pressure in the carpal tunnel via this mass effect. This technique also compresses the median nerve within the carpal tunnel and produces characteristic symptoms to give a positive result of carpal tunnel syndrome 3.
The most characteristic symptoms include burning, tingling, or numb sensation over the thumb, index, middle, and ring fingers. But there’s a question about the sensitivity of this test. Research estimates the sensitivity of the Phalen’s maneuver ranged from 51% to 91% and specificity from 33% to 88% 4.
Your doctor may suggest you to perform another test called “Reverse Phalen’s test”. This reverse Phalen’s test usually performs by maintaining your full wrist and finger extension for two minutes. This test significantly increases pressure in the carpal tunnel within 10 seconds of the wrist posture change. In contrast, the change in carpal tunnel pressure in the standard Phalen’s test results in modest and increases after 20 to 30 seconds 5.
Study found only 4 mm Hg of the average pressure change for standard Phalen’s test at one and two minutes and 34 mm Hg of the average pressure change for the reverse Phalen’s test at one minute 4. Reverse Phalen’s maneuver test increases intra-carpal canal hydrostatic pressure as compared to a standard Phalen’s maneuver test.
Surgery usually cures carpal tunnel syndrome. Before surgery, your physician will decide about the best treatment for you. Your doctor might recommend you to have carpal tunnel surgery after a Phalen’s maneuver if you have 2:
Surgeon will inject local anesthetics to remove your sensation and make a minor cut in your hand. Then, he will cut the carpal tunnel inside your wrist so that it can no longer give pressure on your nerve. This simple procedure requires only 20 minutes to complete and you can get back to your normal activities after a month of your operation 5. After this operation, you do not have to stay in the hospital overnight and the complications are rare.