Infection in primary total knee replacement.
OBJECTIVE
To determine the infection rate and identify the risk factors of primary total knee replacement in a general hospital and discuss possible preventive measure.


METHODS
Retrospective study.


METHODS
Regional hospital, Hong Kong.


METHODS
All cases of primary total knee replacement performed between the period July 1997 and June 2006 were reviewed.


METHODS
Infection rate of primary total knee replacement and its relationship to risk factors.


RESULTS
In the defined period, 479 total knee replacements were performed in 353 patients (291 female and 62 male); 105 women and 21 men had bilateral replacements. The mean patient age was 69 (range, 40-88) years. In all, 447 knees had osteoarthritis, and 32 had rheumatoid arthritis. The mean follow-up period was 46 (range, 1-107) months; 345 knees were followed up longer than 24 months, but seven had no postoperative follow-up. Wound infection was defined by clinical, bacteriological, and/or histological examination. Primary total knee replacement was invariably performed in a theatre with vertical laminar flow, under prophylactic antibiotic cover, and body exhaust suits, water impermeable gowns, and double gloves were always used. The overall infection rate was 3.0% (14/472); the acute deep infection rate (within 4 weeks) was 0.2% (1/472), the delayed deep infection rate (4 weeks-2 years) was 0.6% (2/345). The superficial infection rate was 1.9% (9/472) and the late deep infection rate (after 2 years) was 0.6% (2/345). Diabetic patients had a three-fold higher risk of infection than non-diabetic patients, though this difference did not attain statistical significance (P=0.077).


CONCLUSIONS
Our infection rates for primary total knee replacement were comparable to those encountered internationally.
Fan
Jason C H
JC
Department of Orthopaedics and Traumatology, Alice Ho Miu Ling Nethersole Hospital, Tai Po, Hong Kong. fchjason@netvigator.com
Hung
H H
HH
Fung
K Y
KY
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D003428:Cross Infection / Q000453:epidemiology; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006764:Hospitals, Community / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016459:Prosthesis-Related Infections / Q000453:epidemiology*; D012189:Retrospective Studies; D013530:Surgical Wound Infection / Q000453:epidemiology*