A comparison between directional and proportional methods in locating acupuncture points using dual-energy X-ray absorptiometry in Korean women.

The cun measurement system, an essential and convenient method for locating acupoints, has been widely used in the practice of acupuncture. However, the traditional cun measurement methods have been criticized for their lack of reliability. In addition, new technology has become available to measure the soft tissue and bone mass independently. The present study was conducted in order to determine if one cun, measured by the directional method, is consistent with proportional methods and to investigate whether both methods can be used to locate acupoints. The lengths of bone from several parts of the body in 47 Korean women were measured using Dual-Energy X-ray Absorptiometry. The lengths of each part of the body were compared with 3 cun measured by proportional methods, and the width of all four fingers measured at the level of the proximal inter-phalangeal joint used in the directional method. The results showed that one cun measured by the directional method was significantly different from one cun by proportional methods. The directional method is likely less dependable in locating acupoints than the proportional method.