Location specific radiographic joint space width for osteoarthritis progression

Abstract

Summary Objective To establish the performance of location specific computer measures of radiographic joint space width (JSW) compared to measurements of minimum joint space width (mJSW) for the assessment of medial compartment knee osteoarthritis (OA). The study also investigated the most disease-responsive location for measuring medial compartment JSW. Methods Serial bilateral Posterior Anterior (PA) conventional radiographs acquired with a fixed flexion protocol were obtained 36 months apart in 118 persons with knee OA participating in the Health, Aging and Body Composition (Health ABC) Study. Measurements of medial compartment mJSW and JSW at seven fixed locations were facilitated by the use of semi-automated software that delineated the femoral and tibial margins of the joint. A human reader operated custom software to verify and correct the software-drawn margins where necessary. Paired images were displayed with the reader blinded to the chronological order. The amount of joint space narrowing was measured and the standardized response mean (SRM) was used as a metric to quantify performance. Results For all subjects, the mJSW SRM value was 0.42 while, for the most responsive location specific measure of JSW, it was SRM = 0.46. For subjects with a Kellgren–Lawrence (KL) score less than or equal to 1, mJSW (SRM = 0.40) was more responsive than the new measures (Maximum SRM = 0.30). For KL = 2 or 3, SRM = 0.49 for mJSW, and SRM = 0.74 for the most responsive location specific measure of JSW. Improved responsiveness was observed in the more central portion of the joint on the more diseased knees. Conclusions Location specific computer measures of JSW are feasible and potentially provide a superior method to assess radiographic OA for more diseased subjects. This new measure has the potential to improve the power of clinical studies that use a fixed flexion protocol.

The Intensive Diet and Exercise for Arthritis (IDEA) trial: 18-month radiographic and MRI outcomes

“…1). Based upon superior responsiveness from prior analyses we selected the JSWx ¼ 0.225 as the preferred location for the fixed coordinate JSW measure 25 .…”

Sensitivity of different measures of frontal plane alignment to medial and lateral joint space narrowing: From the osteoarthritis initiative

“…The FTA measurement was defined using a coordinate system to identify the distal aspect of the femoral condyles based on anatomical landmarks for establishing a location-specific joint space width measurement (Fig. 2) [13,14]. Using the largest prominence of the medial and lateral femoral condyles, two lines were identified perpendicular to a tangent at the distal aspect of the condyles.…”

“…However, a novel, highly automated method for measuring FTA was recently presented by Iranpour-Boroujeni et al [12] and alignment data obtained with this method are now available for most of the osteoarthritis initiative (OAI) cohort. This method does not define FTA by the shaft but utilizes more local information around the joint space and femoral condyles [12][13][14]. The authors reported greater intra-rater and inter-rater reliability [12] for measuring FTA than the traditional method in participants with knee OA, and somewhat greater correlation with HKA (r ¼ 0.75) than for the traditional FTA measurements (r ¼ 0.68).…”

Radiological Pain Predictors in Knee Osteoarthritis, a Four Feature Selection Comparison: Data from the OAI

“…1.6, from which quantitative data were obtained, and Right knee symptom status, from which the predicted variable, chronic pain, was obtained. This information was pre analyzed by a radiologist group associated to the OAI using the OARSI quantitative grading scale [28,29][30-32].…”