title: Total Knee Arthroplasty in the Younger Patient.
abstract: The rate of total knee arthroplasty (TKA) utilization in younger patients (< 65 years old) is increasing. Little is known regarding demographics and in-hospital outcomes in this population. The National Hospital Discharge Survey (NHDS) database was searched using International Classification of Diseases, Ninth Revision (ICD-9) procedure codes for patients admitted to U.S. hospitals for unilateral primary TKA between 2001 and 2010. Patients were separated into young (< 65 years of age) and senior cohorts (≥ 65 years of age). ICD-9 diagnosis and procedure codes were used to identify demographics, hospital length of stay, in-hospital adverse events, mortality, and discharge disposition. Trends were evaluated by linear regression with Pearson correlation coefficient (r) and statistical comparisons were made using Studentt-test and chi-square analysis. The young cohort accounted for 38.4% of TKAs performed from 2001 to 2005, increasing to 42.7% of TKAs from 2006 to 2010. They had a higher percentage of males (36.4 vs. 34.2%,p< 0.001). Rates of obesity (11.1 vs. 6.0%,p< 0.001) and morbid obesity (5.8 vs. 1.9%,p< 0.001) were significantly higher, yet they had less comorbidities (4.7 vs. 5.2,p< 0.001), and lower rates of transfusion (12.2 vs. 19.8%,p< 0.001), pulmonary embolism (PE) (0.31 vs. 0.49%,p< 0.020), and mortality (0.03 vs. 0.18%,p< 0.001). Patients < 65 years old undergoing TKA have almost double the rate of obesity of patients ≥ 65 years old. This could explain the higher rates of periprosthetic infection and aseptic mechanical failure seen in younger patients. However, the young cohort had a more favorable discharge disposition and lower mortality and risk of PE than elderly patients.
authors: Department of Orthopaedics, University of Illinois at Chicago, Chicago, Illinois.
authors: Sapan H
authors: SH
authors: Shah
authors: Department of Orthopaedics, University of Illinois at Chicago, Chicago, Illinois.
authors: Brian E
authors: BE
authors: Schwartz
authors: Department of Orthopaedics, University of Illinois at Chicago, Chicago, Illinois.
authors: Aaron R
authors: AR
authors: Schwartz
authors: Department of Orthopaedics, University of Illinois at Chicago, Chicago, Illinois.
authors: Benjamin A
authors: BA
authors: Goldberg
authors: Department of Orthopaedics, University of Illinois at Chicago, Chicago, Illinois.
authors: Samuel J
authors: SJ
authors: Chmell
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000401:mortality*; D002648:Child; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000150:complications / Q000453:epidemiology; D010351:Patient Discharge / Q000706:statistics & numerical data; D011183:Postoperative Complications / Q000453:epidemiology* / Q000209:etiology; D012189:Retrospective Studies; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D055815:Young Adult