Related Experiment Video
Updated: Jun 18, 2026

Non-Invasive Compression-Induced Anterior Cruciate Ligament (ACL) Injury and In Vivo Imaging of Protease Activity in Mice
Published on: September 29, 2023
July--as good a time as any to be injured
R Grant Highstead1, Laura S Johnson, Laura C Johnson
1Washington Hospital Center, Washington, DC, USA.
Background:
Recent studies have suggested worse outcomes for patients hospitalized during the beginning of the academic calendar, though these findings have not been reproduced among trauma patients. This study compares outcomes of patients during the beginning of the academic year with those at the end of the academic year.
Methods:
Retrospective trauma registry analysis of a large urban level I trauma center. Patients admitted during April/May (ENDYEAR group) or July/August (FRESH group) between 1998 and 2007 were included. Demographic and injury parameters were recorded, and outcomes compared including crude mortality, complication rate, length of stay (LOS), and intensive care unit LOS (ICU-LOS). TRISS methodology was used to evaluate risk-adjusted performance.
Results:
Three thousand sixty-seven patients were included in the FRESH group and 3626 in the ENDYEAR group. Groups were similar in age (36 +/- 17 years and 36 +/- 17 years, p = 0.39) and mean Injury Severity Score (8 +/- 11 and 8 +/- 10, p = 0.85). There was no difference in LOS (4.6 +/- 0.2 days versus 4.5 +/- 0.2 days, p = 0.92) or ICU-LOS (5.6 +/- 0.2 days versus 5.3 +/- 0.2 days, p = 0.96). Per patient complication rates for the FRESH and ENDYEAR groups were 6% and 6% (p = 0.8), total complication rates were 12% and 13% (p = 0.07), and crude mortality was 7% and 6% (p = 0.11), respectively. FRESH and ENDYEAR groups had similar W-Statistics (1.0 and 1.2) and z scores (3.5 and 4.4).
Conclusion:
Outcomes were similar between patients injured at the beginning of the academic year compared with the end of the academic year. Our data does not support the concept of a July effect in level I trauma centers.
Related Concept Videos
Burn Injuries
The damage results in the death of skin cells, which can lead to a massive loss of fluid. Dehydration, electrolyte imbalance, and renal and circulatory failure follow, which can be fatal. Burn patients are treated with intravenous fluids to offset...
Fractures: Bone Repair
Minor fractures with no bone displacement are treated by immobilizing the fractured bone using a cast or splint. However, in the case of fractures with displaced bones, the broken bones are repositioned before immobilization to ensure successful healing without deformation and loss of function. The realignment of fractured bone ends is performed through a process called reduction. If the procedure...
The Availability Heuristic
Appendicitis
Acute Kidney Injury III: Clinical Manifestations
Healing II: Complications