Complete absence of acute compartment syndrome was observed in a consecutive series of 966 tibial fractures in African patients of diverse ethnic groups, reviewed retrospectively at our institution. Considering the incidences reported in the literature, we should have experienced between 22 and 86 cases of acute compartment syndrome. The purpose of this prospective study was to confirm these findings and at the same time to look for possible explanations for this unexpected observation. During a period of one year and four months, 257 tibial fractures were prospectively analyzed for clinical signs and late sequelae of acute compartment syndrome. In 156 of these patients, presenting 158 fractures of the tibia, the pressure in the anterior compartment was systematically measured. No single case of compartment syndrome was diagnosed in this series, and no late sequelae of acute compartment syndrome were noted. The hypothesis we forward for total absence of acute compartment syndrome is the favourable effect of the continuously high surrounding temperatures on safeguarding the arteriovenous pressure gradient and lowering the vascular resistance. We suggest that further investigation should be carried out to study this hypothesis.