Incidence of First-Time Lateral Patellar Dislocation: A 21-Year Population-Based Study

Area of Science:

• Orthopaedic epidemiology
• Patellofemoral joint biomechanics
• Public health surveillance

Background:

• First-time lateral patellar dislocation is a common orthopaedic injury.
• Understanding its incidence and trends is crucial for public health and clinical management.
• Adolescents represent a key demographic for this injury.

Purpose of the Study:

• To determine the incidence of first-time lateral patellar dislocation in a defined population.
• To analyze temporal trends in patellar dislocation rates.
• To report the surgical treatment rates for this condition.

Main Methods:

• A retrospective cohort study design was employed.
• Data were collected from a geographic cohort county database (1990-2010).
• Age- and sex-specific incidence rates were calculated and analyzed for trends using Poisson regression.

Main Results:

• The overall age- and sex-adjusted incidence was 23.2 per 100,000 person-years.
• Adolescents aged 14-18 years exhibited the highest incidence (147.7/100,000 person-years).
• A significant decline in incidence was observed in adolescent girls and young men, yet the overall rate remained stable.

Conclusions:

• Lateral patellar dislocation is a frequent orthopaedic injury with a notable incidence in adolescents.
• The incidence in adolescents is higher than previously documented.
• Despite some declining trends, the overall incidence remained consistent over the study period.