Breast Capsule Thickness and Clinical Capsular Contracture: A Systematic Review and Meta-Analysis.

Background: Capsular contracture is a leading cause of morbidity after breast augmentation and often necessitates reoperation. This study analyzes the association between breast capsule thickness and severity of capsular contracture, distinguishing benign from pathological cases.

Methods: Literature review was conducted across PubMed, Medline, and Web of Science according to PRISMA guidelines, for articles published between 2014 and 2024. Data extracted included author, year, sample size, age, implant type, capsule thickness, capsular contracture presence, and Baker score. A permutation test determined a minimum thickness cutoff associated with capsular contracture. Statistical meta-analysis, permutation analysis, and univariate Poisson regression were conducted using R 4.4.1 (Boston, MA).

Results: Of 649 publications, 12 met inclusion criteria, examining 590 breast samples from 403 patients. The mean capsular thickness was 708 µm. The capsular contracture rate was 47.6% of breasts and in 69.7% of patients. Meta-regression of 534 samples across nine studies including 25 unique patient groupings showed a pooled capsular contracture rate in breasts of 58.2% (95% CI: 28.2-83.1). Capsular thicknesses in the highest (OR 23.99, 95% CI: 13.31-45.10, p < 0.001) and middle (OR 16.22, 95% CI: 9.95-27.16, p < 0.001) tertiles had higher odds of contracture compared to the lowest tertile. Univariate Poisson regression showed a 0.069% (95% CI: 0.050-0.087, p < 0.001) increase in contracture per micrometer of capsule thickness. The minimum significant cutoff was 601.5 µm (p < 0.05), below which studies had significantly lower capsular contracture rates.

Conclusions: Capsule thickness correlates with capsular contracture, suggesting a measurable predictor for pathological contracture.

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