Evaluation of Peripheral Vascular Impairment in the Fingers of Baseball Players

Abstract

PURPOSE: Digital vessel trauma from repetitive impact on the fingers and hand is a concern for baseball players (BPs). Laser-Doppler blood perfusion imaging (LDPI) is a technique that employs two-dimensional horizontal scanning of the blood flow in a specific tissue, without the necessity for surface contact. The LDPI method may have the benefit of detecting vasospastic abnormalities and occlusion of the digital arteries, which generally appears as an inhomogeneous reaction to the cold. This study used LDPI to investigate whether the changes in finger skin blood flow that occurred in response to a cold water immersion test depended on the position of BPs. METHODS: The study included 57 male university BPs, aged 20 ± 1 years, who play at 3 different positions. From this study subject group, there were: 18 pitchers, 23 infielders (InF), and 16 outfielders (OtF). A cold provocation test was carried out by immersing a subject’s catching hand into cold water (10°C) for 10 min. Repeated image scanning of skin blood flow on the palm was performed every 2 min before, during, and after cold water immersion, by using LDPI. The mean blood perfusion values in the index finger area were calculated on each color-coded image. A numerical perfusion reading was also obtained for each measurement site in terms of the voltage (V). From the perfusion reading and the mean blood pressure, we calculated the cutaneous vascular conductance (CVC). The finger skin temperature was recorded by using an electrode thermistor attached to the skin on the dorsal side of the index finger. RESULTS: CVC values of the InF were significantly lower compared with those of the OtF at pre-immersion (2.4 ± 0.6 V/mmHg vs. 3.3 ± 1.0 V/mmHg, p < 0.01) and at early post-immersion (1.2 ± 0.4 V/mmHg vs. 1.5 ± 0.5 V/mmHg, p < 0.05). However, the index finger skin temperature did not significantly differ among the different player positions at any measurement point. CONCLUSIONS: These findings suggest that the changes in finger skin blood flow that occurred in response to cold water immersion, as measured by using LDPI, were dependent on the position of the BP. Repetitive trauma caused by the impact of a baseball also leads to peripheral vascular impairment in the index finger on the gloved hand of InF. Therefore, this method can be used for the assessment of peripheral circulatory function in BPs.