CT and MRI studies reflect that people who present with carpal tunnel syndrome have a smaller carpal canal, and this correlates with an increased pressure within the carpal tunnel confirmed by needle pressure transducer pressure measurement.Computerized tomography (CT) and magnetic resonance imaging (MRI) studies performed at the Mayo Clinic and elsewhere confirmed the reliability of assessing carpal tunnel volume with these modalities. Thus, one can look at the carpal tunnel before and after endoscopic carpal tunnel release and tell what the volume is.
The most likely person to develop carpal tunnel syndrome is a woman over the age of 30 with a family history of hand pain or numbness. Diabetes, obesity and arthritis involving the neck (cervical spine) and/or the base of the neck are additional risk factors.
Identical Twins
Identical twins only rarely identify themselves as such unless they are seen directly together; i.e. even when taking family history, oftentimes an identical twin will go unnoted because a person doesn't designate them as such. Whether this is because they don't like to draw attention to their identical twin or they think nothing of it is unclear. In fact, in the United States, identical twins are quite a frequent occurrence.
It stands to reason that if the shape and size of the wrist are responsible for the pressure within the wrist that an identical twin would be more likely than not to develop carpal tunnel syndrome if their counterpart had developed it. In fact, when we are able to get the identical in for questioning and testing, even those that are asymptomatic, I have usually been able to identify obvious significant nerve entrapment at the level of the carpal tunnel and sometimes cubital tunnel, as well. The youngest identical twins I have identified this on were about 16 years old.