Effect of smoking and soft tissue release on risk of revision after total knee arthroplasty: a case- control study.
BACKGROUND
Increasing utilization of primary total knee arthroplasty (TKA) is projected to expand demand for revision TKA. Revision TKAs are procedurally complex and incur high costs on our financially constrained healthcare system. The purpose of this study was to use a case-control design to identify factors predisposing to revision TKA, particularly demographic, clinical and perioperative technical factors.


METHODS
We conducted a case control study to investigate patient, surgical and perioperative factors associated with greater risk of revision TKA. We included patients who received TKA at a tertiary center between 1996 and 2009. Cases (patients that had primary and revision TKA) were matched to controls (patients with primary TKA that was not revised) in a 1:2 ratio and risk of revision examined using conditional logistic regression.


RESULTS
We identified 146 cases and 290 controls. Patient factors independently associated with revision included male sex (OR 1.73; 95% CI 1.06-2.81) and smoking (OR 2.87; 1.33-6.19). Older age was associated with decreased risk (OR 0.83 per 5-year increment; 95% CI 0.75-0.92). Lateral release was the only technical factor associated with revision (OR 1.92; 1.07-3.43).


CONCLUSIONS
In this case control study younger patient age, male gender, soft tissue release and active smoking status were associated with increased revision risk. Although we do not know whether the risk of smoking arises from short- or long-term exposure, smoking cessation prior to TKA should be considered as an intervention for decreasing revision risk.
The Department of Orthopedic Surgery, Hospital for Special Surgery, New York, USA. nwachukwub@hss.edu.
Benedict U
BU
Nwachukwu
Department of Orthopedic Surgery, Boston, USA. EGURARY@partners.org.|Department of Biostatistics, Boston University School of Public Health, Boston, USA. EGURARY@partners.org.
Ellen B
EB
Gurary
Department of Orthopedic Surgery, Massachusetts General Hospital, Boston, USA. VLERNER@mgh.harvard.edu.
Vladislav
V
Lerner
Department of Orthopedic Surgery, Boston, USA. JCOLLINS13@partners.org.
Jamie E
JE
Collins
Department of Orthopedic Surgery, Boston, USA. TTHORNHILL@partners.org.
Thomas S
TS
Thornhill
Department of Orthopedic Surgery, Boston, USA. ELOSINA@partners.org.|Division of Rheumatology, Immunology and Allergy, Boston, USA. ELOSINA@partners.org.|Department of Biostatistics, Boston University School of Public Health, Boston, USA. ELOSINA@partners.org.
Elena
E
Losina
Department of Orthopedic Surgery, Boston, USA. jnkatz@partners.org.|Division of Rheumatology, Immunology and Allergy, Boston, USA. jnkatz@partners.org.|Orthopedic and Arthritis Center for Outcomes Research, Brigham and Women's Hospital, 75 Francis Street, BC-4016, Boston, MA, 02115, USA. jnkatz@partners.org.
Jeffrey N
JN
Katz
D000328:Adult; D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000639:trends*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology*; D011475:Prosthesis Failure / Q000009:adverse effects / Q000639:trends*; D012086:Reoperation / Q000639:trends; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology* / Q000639:trends*; D017695:Soft Tissue Injuries / Q000175:diagnosis / Q000453:epidemiology*; D016896:Treatment Outcome