Login to Access Video or Poster Abstract: 561
Date & Time: May 15, 2011 03:30 PM
Session Title: Pediatrics: Congenital Anomalies - Lower Urinary Tract & Genitalia
Sources of Funding: Source of Funding: none

INTRODUCTION AND OBJECTIVES:
The etiology of testicular torsion is not well described. It has been hypothesized that colder temperatures cause asymmetric contraction of the cremaster muscle leading to asymmetric rotation with consequent twisting and elevation of the spermatic cord in susceptible patients. Consequently, testis torsion has come to be regarded as more common in colder months as an ?urban legend? without evidence. Prior single institution studies on seasonal or temperature variation in the incidence of testicular torsion have not definitively answered this hypothesis. Our objective was to determine whether testicular torsion is more common in colder weather using a national pediatric dataset.

METHODS:
Using the 2000, 2003 and 2006 Healthcare Cost and Utilization Project Kids? Inpatient Database (KID), testicular torsion events were identified using a diagnosis of torsion combined with a procedure for orchiopexy or orchiectomy. The percentage of cases occurring each month on a national and regional level was determined using both unweighted and weighted data. As some states do not have sufficient temperature variation to plausibly lead to testicular torsion, subgroup analysis was performed using only ?cold states,? those having an average temperature <5° Celsius for ?4 months per year. The hypothesis that the incidence of testicular torsion is higher in colder seasons than expected was tested with ?2 goodness of fit analysis.

RESULTS:
There were 2413 episodes of testicular torsion among boys ?18 years reported in the 2000, 2003 and 2006 KID: winter (26.9%), spring (25.7%), summer (23.5%) and fall (23.8%). This was not significantly different from the null hypothesis of equivalent distribution among the different seasons (p=0.06). At a regional level, the seasonal distribution of cases (winter, spring, summer, fall, respectively) was: Northeast (27.5%, 25.7%, 23.4%, 23.4%), Midwest (25.5%, 25.7%, 26.8%, 22.0%), South (26.8%, 25.7%, 23.2%, 24.3%) and West (27.2%, 25.8%, 22.1%, 24.9%). Limiting analysis to cold states, the distribution was winter 26.9%, spring 26.0%, summer 23.6%, and fall 23.5% (p=0.25). There was not significant variation in the monthly distribution of torsion events for all states and for cold states only. These data observations were unchanged when weighted national estimates were calculated for each month accounting for hospital strata, clustering and discharge weight.

CONCLUSIONS:
Testicular torsion is evenly distributed across all seasons. The hypothesis that cold weather is related to the incidence of testicular torsion is not supported by data from a large representative national dataset.

Authors

Casey, Jessica T.; Lautz, Timothy B.; Zhao, Lee C.; Maizels, Max