Positive Factors Linked with Carpal Tunnel Syndrome Pain

Not everyone with carpal tunnel syndrome (CTS) experiences wrist or hand pain as a symptom. In fact, many people with CTS have numbness as the main problem. But that numbness can be so severe that it is interpreted by the brain as “pain”. In this study, researchers explored the possible factors linked with carpal tunnel syndrome pain.

The study involved 275 adults (ages 22 to 87) who were formally diagnosed with carpal tunnel syndrome (CTS) using history, nerve conduction studies, and clinical tests. Everyone was carefully assessed based on demographic factors such as tobacco use (smoking), body mass index (BMI), past medical history, and occupation. Age, hand dominance, use of tools that vibrate, and other health concerns were also noted.

Evidence from studies done so far support the understanding that carpal tunnel syndrome (CTS) usually presents with numbness, weakness, and atrophy of the muscles of the hand. There is no evidence that pain as a symptom is linked with (or will predict) positive results with nerve conduction studies.

There is sufficient evidence now to show that positive nerve conduction tests are a reliable diagnostic tool for CTS. Finding a symptom or other clinical test that might correlate with nerve conduction testing would be very helpful in predicting who might be experiencing CTS. This information could lead more quickly to an accurate diagnosis of CTS.

The researchers who conducted this study had two other questions (besides whether pain is a factor predicting carpal tunnel syndrome). They wanted to know if a specific questionnaire known as the Short Form-McGill pain questionnaire (SF-MPQ) would be a helpful tool for predicting CTS based on pain as a symptom. They also wanted to know if pain at the time of diagnosis was a factor in the later outcomes (results after one year).

Here are a few of the study findings:

  • Most of the patients (92 per cent) were right-handed.
  • Sixty per cent (60%) had bilateral carpal tunnel syndrome (i.e., affecting both hands).
  • One-third were smokers or used vibratory tools.
  • Nerve conduction tests were positive in 92 per cent of the group.

    The Phalen Sign (clinical test used to diagnose carpal tunnel syndrome) was positive in 91 per cent of the patients. A second test often used (Tinel sign) was only positive in 28 per cent of the group.
    Only one per cent of the patients were treated successfully (for pain) using wrist splints.

    Analysis of all the data drilled the results down to the following:

  • Pain did not correlate with exam findings or nerve conduction tests.
  • Smoking and bilateral carpal tunnel syndrome were the two factors that were linked with pain. Smoking was a stronger predictive factor than bilateral pain.
  • Pain was not a predictor of outcomes (i.e., getting better after a year’s time).
  • Nerve conduction tests are indeed an important way to confirm the diagnosis and should be done before starting treatment.

    Other studies have shown that depression or chronic pain can be the reason people smoke. So, tobacco use may not be the cause of the pain as much as other factors linking these two things together. And other studies have provided evidence that pain intensity with carpal tunnel syndrome is a direct effect of depression or nervous system dysfunction.

    The authors of this study concluded that pain is not a classic symptom of carpal tunnel syndrome. The questionnaire used (SF-MPQ) did not show pain linked with carpal tunnel syndrome. They question whether pain should be included in any diagnostic test such as the questionnaires often used to assess symptoms. They suggest that pain and numbness must be separated out as symptoms.