Normative spleen size in tall healthy athletes: implications for safe return to contact sports after infectious mononucleosis.

OBJECTIVE

To establish normative parameters of the spleen by ultrasonography in tall athletes.

DESIGN

Prospective cohort observational study.

SETTING

University of Buffalo, Erie County Community College, University of Texas at Tyler, and Austin College.

PARTICIPANTS

Sixty-six athletes enrolled and finished the study. Height requirements were at least 6 feet 2 inches for men and at least 5 feet 7 inches in women.

INTERVENTIONS: Measurement of spleen size in tall athletes.

MAIN OUTCOME MEASURES: Ultrasound measurements of spleen size in tall athletes were compared with "normal-sized" controls from the literature. Mean, SD, and variance determined the sample distribution, and a one sample t test compared measurements in tall athletes with historical measurements in the average height population. Statistical significance was defined as P < 0.05.

RESULTS

Mean height was 192.26 cm (SD, ± 6.52) for men and 176.54 cm (SD, ± 5.19) for women. Mean splenic measurements for all subjects were 12.19 cm (SD, ± 1.45) for spleen length, 8.88 cm (SD, ± 0.96) for spleen width, and 5.55 cm (SD, ± 0.76) for spleen thickness. The study mean for spleen length was 12.192 cm (95% confidence interval, 11.835-12.549) and population mean was 8.94 cm (2 tailed t test, P < 0.01). In this population of tall athletes, normal spleen size was significantly larger than the normal spleen size of an average individual.

CONCLUSIONS

In the clinical arena, it can be difficult to know when the tall athletes with splenomegaly from infectious mononucleosis can safely return to contact sports. Previously, there has not been a sufficient "norm" for this population, but this study helps to establish baseline values.