Development of a novel Triage Tool for Total Knee Surgery
Mark Harrison MD, FRCS(C), Mike Brean B.IS, Wilma Hopman MSc, John Hope BSc, T. Derek
Cooke FRCS(C)
Departments of Surgery and School of Rehabilitation Therapy Queens University, Kingston
General and Hotel Dieu Hospitals
Summary:
Objective: To evaluate a triage tool, based on patient self-report disability assessment and standardized
radiographic score, to determine appropriateness for total knee arthroplasty surgery.
Design: A prospective study to compare the triage tool with information from the referral letter.
Setting: Academic Health Science Centre
Participants: Patients referred to the adult orthopaedic knee clinic over a 1-year period.
Interventions: Patients underwent a standardized battery of self- report disability questionnaires and
standardized radiographs in addition to their usual consult with an orthopedic surgeon.
Results: Of the 172 patients assessed, 131 were appropriate for surgery and 81 of subjects underwent
surgery.
The information provided in the referral letter was not sufficient to calculate urgency and did not
correlate with whether patients were booked for surgery. The triage tool based on the self-report
disability questionnaire and standardized radiographic score correlated strongly with the subject being
appropriate for TKA (p<.001).
Objective: To evaluate a triage tool, based on patient self-report disability assessment and standardized
radiographic score, to determine appropriateness for total knee arthroplasty surgery.
Methods:
Subjects were 181 adults over age 40 with complaints of knee pain enrolled from the new
patient referrals of the knee clinic at a medium sized Canadian academic centre. Participants
completed 5 disability questionnaires: SF 12; WOMAC; Tegner & Lysholm questionnaire; Functional
Comorbidity Index; and an Inflammatory Disorder Questionnaire prior to their orthopaedic
consultation.
Standardized radiographic assessment was performed on a standing frontal and ten degree
skyline images for joint space (0-3), osteophytes (0-3), erosion (0-4) and subluxation (0-3).
Radiographic assessment was performed by trained readers who were blinded to the clinical data.
The primary care physician referral letter was scored based on the NHS-NICE guidelines for
pain, disability, sleeplessness, loss of independence and impairment of daily activities to determine if it
contained the necessary information to allow for assessment of urgency and need for surgery.
The diagnosis and decision for surgery was performed by the orthopedic surgeon independent
from the data collection of the clinical disability questionnaires. The consultation letter from
orthopedic surgeon to family physician was reviewed to determine if the subject was appropriate for
surgery independent of whether surgery occurred.
Results:
Nine subjects were excluded due to diagnoses other than knee pain, leaving 172 subjects
included in the analysis.
The majority of referral letters from the family physician did not include the minimum data
necessary to allow for prioritization of the referral regarding the urgency of the patient’s condition.
Fewer than 41% of letters contained information regarding pain severity, limitations in ADLs or
disability. There was no correlation between whether the referral letter addressed these criteria and
whether the patient was appropriate for and/or booked for surgery.
131 subjects were deemed appropriate for surgery by the orthopaedic surgeon; however, only
81 underwent surgery. The 50 subjects who did not undergo surgery had multiple reasons for their
decision not to have surgery including: minimal impairment in daily activities (39); morbid obesity (7);
unstable medical condition (7); and age (9).
Subjects deemed appropriate for surgery (n=131) compared to those not appropriate for surgery
(n=41) were statistically older 66.9 (SD 10.2) years versus 61.3 (SD10.1) (P<.001), with worse WOMAC
arthritis specific disability scores 45.4 (SD 19) versus 32.8 (SD17) and worse WCWL-HKPT scores 46.9
(SD23) versus 28.5 (SD20) and had higher radiographic scores of 5.97 (SD 2.2) versus 3.8 (SD 1.2)
Stepwise multiple regression analysis was performed to assess the factors that determined if patients
were appropriate for surgery. Initially all questionnaires were included in the regression model, but
items were excluded if they did not have statistical significance. The variables in the final regression
model that predicted if subjects “were appropriate for surgery” were age (p =.003), WOMAC total
score (p= .011) and total radiographic score (p<.001). The regression model suggested that the odds
ratio of being appropriate for surgery increased by 1.86 times for every one-point increase in total xray score, by 1.90 times for every ten year increase in age and by 1.32 times with each 10-point
increase in WOMAC.
Conclusion: These results suggest that an evidence based triage tool based on the combination of
Disability Evaluation and Radiographic Grading may be useful in determining the need for TKA surgery. It
may allow for patients with high scores to be seen rapidly by an arthroplasty surgeon, while subjects with
low scores may be referred for non-surgical care.