Body mass index (BMI) and associations of periprosthetic fracture risk after TKA: A systematic review

Abstract

Introduction: Total knee arthroplasty (TKA) is one of the most common elective orthopaedic surgeries. Periprosthetic fracture is a rare but potentially devastating complication after TKA. Several known risk factors exist, but the association of body mass index (BMI) with periprosthetic fractures remains largely unknown. This study aims to determine if increased BMI correlates with increased rates of periprosthetic fractures around a TKA. Methods: A systematic review was conducted across MEDLINE/Pubmed, Cochrane, and Embase databases to evaluate for BMI and TKA periprosthetic fracture. The search used a combination of keywords and Medical Subject Heading (MeSH) terms. Titles and abstracts were screened for inclusion criteria. Full texts were screened and incorporated into this review if they met the inclusion criteria. Meta-analysis was not conducted due to different classifications of BMI categories used and wide variations in statistical analysis and reporting methods in the primary studies. Results: This review found four retrospective cohort studies and one retrospective case-control study, all level 3 evidence. The studies' results were mixed, and there was no clear association between BMI and the risk of periprosthetic fracture following TKA. Articles that met inclusion criteria in this review demonstrated a lack of a clear and standardized categorization for BMI which prevented meta-analysis of the data. Conclusion: BMI does not currently exhibit any clear association with the risk of periprosthetic fracture in patients who undergo TKA. Additional prospective and retrospective evidence with standardized BMI classes and longer study durations are needed to determine if BMI is truly associated with the risk of periprosthetic fracture. Level of evidence: III.

Keywords

• BMI
• Periprosthetic fracture
• Obesity
• Underweight
• Overweight