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Updated: Jun 3, 2026
Standardized Histomorphometric Evaluation of Osteoarthritis in a Surgical Mouse Model
Published on: May 6, 2020
Summary and recommendations of the OARSI FDA osteoarthritis Assessment of Structural Change Working Group
P G Conaghan1, D J Hunter, J F Maillefert
1Section of Musculoskeletal Disease, University of Leeds, Leeds, UK. p.conaghan@leeds.ac.uk
Objective:
The Osteoarthritis Research Society International initiated a number of working groups to address a call from the US Food and Drug Administration (FDA) on updating draft guidance on conduct of osteoarthritis (OA) clinical trials. The development of disease-modifying osteoarthritis drugs (DMOADs) remains challenging. The Assessment of Structural Change (ASC) Working Group aimed to provide a state-of-the-art critical update on imaging tools for OA clinical trials.
Methods:
The Group focussed on the performance metrics of conventional radiographs (CR) and magnetic resonance imaging (MRI), performing systematic literature reviews for these modalities. After acquiring these reviews, summary and research recommendations were developed through a consensus process.
Results:
For CR, there is some evidence for construct and predictive validity, with good evidence for reliability and responsiveness of metric measurement of joint space width (JSW). Trials off at least 1 and probably 2 years duration will be required. Although there is much less evidence for hip JSW, it may provide greater responsiveness than knee JSW. For MRI cartilage morphometry in knee OA, there is some evidence for construct and predictive validity, with good evidence for reliability and responsiveness. The responsiveness of semi-quantitative MRI assessment of cartilage morphology, bone marrow lesions and synovitis was also good in knee OA.
Conclusions:
Radiographic JSW is still a recommended option for trials of structure modification, with the understanding that the construct represents a number of pathologies and trial duration may be long. MRI is now recommended for clinical trials in terms of cartilage morphology assessment. It is important to study all the joint tissues of the OA joint and the literature is growing on MRI quantification (and its responsiveness) of non-cartilage features. The research recommendations provided will focus researchers on important issues such as determining how structural change within the relatively short duration of a trial reflects long-term change in patient-centred outcomes.
Insights
Conventional radiography and MRI are effective imaging tools for osteoarthritis clinical trials. Radiographic joint space width is recommended for structural modification trials, while MRI is preferred for cartilage assessment, guiding future research for disease-modifying osteoarthritis drugs.
Area of Science:
- Orthopedics and Rheumatology
- Medical Imaging
- Clinical Trial Design
Background:
- Osteoarthritis Research Society International (OARSI) working groups addressed FDA guidance for osteoarthritis (OA) clinical trials.
- Developing disease-modifying osteoarthritis drugs (DMOADs) presents significant challenges.
- The Assessment of Structural Change (ASC) Working Group focused on updating imaging tools for OA trials.
Framework:
- Systematic literature reviews evaluated performance metrics for conventional radiography (CR) and magnetic resonance imaging (MRI).
- Consensus processes synthesized review findings into summary and research recommendations.
- Focus on reliability, responsiveness, construct validity, and predictive validity of imaging metrics.
Implementation:
- CR: Joint space width (JSW) shows good reliability and responsiveness, particularly for hip JSW, though trials may require 1-2 years.
- MRI: Cartilage morphometry in knee OA demonstrates good reliability and responsiveness.
- MRI: Semi-quantitative assessment of cartilage, bone marrow lesions, and synovitis shows good responsiveness in knee OA.
Implications:
- Radiographic JSW remains a viable option for structure modification trials, acknowledging potential long trial durations.
- MRI is now recommended for cartilage morphology assessment in OA clinical trials.
- Future research should integrate imaging of all joint tissues and correlate short-term structural changes with long-term patient outcomes.
