Short-Term Outcomes of Noncemented Total Knee Arthroplasty in Patients With Morbid Obesity.

Introduction: Noncemented primary total knee arthroplasty (TKA) compromises over 14% of all primary TKA procedures reported in the American Joint Replacement Registry. While studies have indicated similar outcomes for cemented and noncemented TKA in obese individuals, the efficacy and safety of noncemented TKA in morbidly obese patients (body mass index [BMI] ≥ 40 kg/m2) remain unexplored. This study compares short-term postoperative outcomes and complications between noncemented and cemented TKA in morbidly obese patients.

Methods: A retrospective review of 605 cases of patients with a BMI of at least 40 kg/m2 (22.5% of 2,691 total cases at a single tertiary center) who underwent TKA was conducted. All patients had a minimum follow-up of 1 year. Data collected included age, BMI, sex, race, ethnicity, American Society of Anesthesiologists status, and the Charlson Comorbidity Index. Postoperative complications were tracked, including 90-day readmission, 1-year mortality, 1-year revision surgery, wound complications, fractures, and infections. Categorical variables were analyzed with chi-square tests and continuous variables with t-tests.

Results: Of the included patients with a BMI ≥ 40 kg/m2, 40 (6.6%) received noncemented TKA. The noncemented TKA group had a lower mean BMI (43.3 ± 3.1 vs. 45.0 ± 4.4; P = 0.012) and a higher proportion of male patients compared with the cemented group (n = 17 [42.5%] vs. n = 143 [25.3%]; P = 0.028). Surgical time was shorter for noncemented TKA (97 ± 27 minutes) than for cemented TKA (118.0 ± 39.4 minutes; P = 0.001). No significant differences were found in length of stay and postoperative complications, including 90-day readmission, 1-year mortality, revision surgery rates, wound complications, fractures, and infections.

Conclusion: The findings of the study suggest that noncemented TKA may be a feasible, safe alternative and not inferior to the standard cemented TKA in patients with morbid obesity with the benefit of decreasing surgical time.