Outcome of total hip arthroplasty, but not of total knee arthroplasty, is related to the preoperative radiographic severity of osteoarthritis. A prospective cohort study of 573 patients.
OBJECTIVE
There is no consensus on the impact of radiographic severity of hip and knee osteoarthritis (OA) on the clinical outcome of total hip arthroplasty (THA) and total knee arthroplasty (TKA). We assessed whether preoperative radiographic severity of OA is related to improvements in functioning, pain, and health-related quality of life (HRQoL) 1 year after THA or TKA.


METHODS
This prospective cohort study included 302 THA patients and 271 TKA patients with hip or knee OA. In the THA patients, preoperatively 26% had mild OA and 74% had severe OA; in the TKA patients, preoperatively 27% had mild OA and 73% had severe OA. Radiographic severity was determined according to the Kellgren and Lawrence (KL) classification. Clinical assessments preoperatively and 1 year postoperatively included: sociodemographic characteristics and patient-reported outcomes (PROMs): Oxford hip/knee score, hip/knee injury and osteoarthritis outcome score (HOOS/KOOS), SF36, and EQ5D. Change scores of PROMs were compared with mild OA (KL 0-2) and severe OA (KL 3-4) using a multivariate linear regression model.


RESULTS
Adjusted for sex, age, preoperative scores, BMI, and Charnley score, radiographic severity of OA in THA was associated with improvement in HOOS "Activities of daily living", "Pain", and "Symptoms", and SF36 physical component summary ("PCS") scale. In TKA, we found no such associations.


CONCLUSIONS
The decrease in pain and improvement in function in THA patients, but not in TKA patients, was positively associated with the preoperative radiographic severity of OA.
a Department of Orthopaedics , Leiden University Medical Center , Leiden , the Netherlands.
Claire
C
Tilbury
a Department of Orthopaedics , Leiden University Medical Center , Leiden , the Netherlands.
Maarten J
MJ
Holtslag
b Department of Orthopaedics , Rijnland Hospital , Leiderdorp , the Netherlands.
Rutger L
RL
Tordoir
a Department of Orthopaedics , Leiden University Medical Center , Leiden , the Netherlands.
Claudia S
CS
Leichtenberg
b Department of Orthopaedics , Rijnland Hospital , Leiderdorp , the Netherlands.
Suzan H M
SH
Verdegaal
c Department of Radiology , Leiden University Medical Center , Leiden , the Netherlands.
Herman M
HM
Kroon
d Department of Medical Statistics and Bioinformatics , Leiden University Medical Center , Leiden , the Netherlands.
Marta
M
Fiocco
a Department of Orthopaedics , Leiden University Medical Center , Leiden , the Netherlands.
Rob G H H
RG
Nelissen
a Department of Orthopaedics , Leiden University Medical Center , Leiden , the Netherlands.
Thea P M
TP
Vliet Vlieland
D000328:Adult; D000367:Age Factors; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000379:methods*; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods*; D016009:Chi-Square Distribution; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D010147:Pain Measurement; D011183:Postoperative Complications / Q000453:epidemiology / Q000503:physiopathology; D011300:Preoperative Care / Q000379:methods; D011446:Prospective Studies; D011475:Prosthesis Failure; D011859:Radiography; D020127:Recovery of Function; D012086:Reoperation / Q000379:methods; D018570:Risk Assessment; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D016896:Treatment Outcome