Hall Joanna, Laslett Laura L, Martel-Pelletier Johanne, Pelletier Jean-Pierre, Abram François, Ding Chang-Hai, Cicuttini Flavia M, Jones Graeme
Menzies Institute for Medical Research, University of Tasmania, Private Bag 23, Hobart, Tasmania, 7000, Australia.
Osteoarthritis Research Unit, University of Montreal Hospital Research Centre (CRCHUM), Montreal, Quebec, Canada.
BMC Musculoskelet Disord. 2016 Jan 14;17:25. doi: 10.1186/s12891-016-0879-0.
Change in knee cartilage volume is frequently used as a proxy for change in knee joint space width over time, but longitudinal data on these associations is limited. We aimed to determine whether change in knee cartilage volume, new or worsening meniscal extrusion (ME), meniscal tears and cartilage defects over 2.4 years correlated with change in joint space width (JSW) over 5 years in older community dwelling adults.
Participants (n = 153) had their right knee imaged using MR imaging and x-ray at baseline, and after 2.4 years (MRI) and 5 years (x-ray). Cartilage volume, cartilage defects, meniscal extrusions and meniscal tears were assessed on sagittal T1-weighted fat-suppressed MRI. JSW was assessed using standard fixed semi-flexed view radiographs, and scored on those with adequate alignment.
Participants were 51-79 (mean 62) years old; 48% were female. Cartilage volume reduced over time (medial -134 ± 202 μL/year, lateral -106 ± 165 μL/year, p < 0.001), as did JSW (medial -0.05 ± 0.16 mm/year, lateral -0.12 ± 0.24 mm/year, p < 0.001). In multivariable analysis, the only consistent predictor of change in JSW was new or worsening ME (medial tibia R(2) 3.1%, p = 0.031; medial femur R(2) 3.2%, p = 0.024); change in cartilage volume correlated with change in JSW laterally (R(2) 4.8%, p = 0.007) and was borderline medially (R(2) 2.2%, p = 0.064); there was no association for meniscal tears or cartilage defects. The magnitude of these associations were similar albeit somewhat greater for ME in participants with radiographic OA (R(2) 6.2%, p = 0.017).
Change in ME and cartilage volume weakly predict change in JSW, but the vast majority of the variation remains unexplained. Since MRI examines cartilage directly while radiographs examine it indirectly, these results cast doubt on the validity of using JSW as a proxy measure of cartilage loss.
膝关节软骨体积的变化常被用作膝关节间隙宽度随时间变化的替代指标，但关于这些关联的纵向数据有限。我们旨在确定在2.4年中膝关节软骨体积的变化、新出现或加重的半月板挤出（ME）、半月板撕裂和软骨缺损是否与老年社区居住成年人5年中关节间隙宽度（JSW）的变化相关。
参与者（n = 153）在基线时、2.4年后（MRI）和5年后（X线）对其右膝进行磁共振成像（MR成像）和X线成像。在矢状面T1加权脂肪抑制MR图像上评估软骨体积、软骨缺损、半月板挤出和半月板撕裂。使用标准的固定半屈曲位X线片评估JSW，并对那些对线良好的片子进行评分。
参与者年龄在51 - 79岁（平均62岁）；48%为女性。软骨体积随时间减少（内侧 -134±202 μL/年，外侧 -106±165 μL/年，p < 0.001），JSW也随时间减少（内侧 -0.05±0.16 mm/年，外侧 -0.12±0.24 mm/年，p < 0.001）。在多变量分析中，JSW变化的唯一一致预测因素是新出现或加重的ME（胫骨内侧R(2) 3.1%，p = 0.031；股骨内侧R(2) 3.2%，p = 0.024）；软骨体积的变化与外侧JSW的变化相关（R(2) 4.8%，p = 0.007），在内侧接近临界值（R(2) 2.2%，p = 0.064）；半月板撕裂或软骨缺损无关联。在有放射学骨关节炎的参与者中，这些关联的程度相似，尽管ME的关联程度略大（R(2) 6.2%，p = 0.017）。
ME和软骨体积的变化对JSW变化的预测作用较弱，但绝大多数变化仍无法解释。由于MR成像直接检查软骨，而X线片间接检查软骨，这些结果对将JSW用作软骨丢失替代指标的有效性提出了质疑。
