Institute of Anatomy, Paracelsus Medical University, Salzburg and Nuremberg, Salzburg, Austria, and Chondrometrics GmbH, Ainring, Germany.
Arthritis Rheumatol. 2015 Jan;67(1):152-61. doi: 10.1002/art.38881.
Anterior cruciate ligament (ACL) rupture involves an increased risk of osteoarthritis. The purpose of this study was to explore changes in cartilage thickness over 5 years after ACL rupture.
A total of 121 young active adults (ages 18-35 years; 26% women) from the Knee ACL, Nonsurgical versus Surgical Treatment (KANON) study, who had acute traumatic rupture of the ACL were studied. Sagittal magnetic resonance images were acquired within 4 weeks of ACL rupture (baseline) and at the 2-year and 5-year followup assessments. Medial and lateral femorotibial cartilage was segmented (with blinding to acquisition order), and the mean cartilage thickness was computed across 16 femorotibial subregions. Total femorotibial cartilage thickness change was the primary analytic focus. Maximal subregional mean cartilage thickness loss (ordered value 1 [OV1]) and gain (ordered value 16 [OV16]), independent of its specific location in individual knees, were the secondary analytic focus.
Overall femorotibial cartilage thickness increased by 31 μm/year over 5 years (95% confidence interval 18, 44). The increase was similar in men and women and was significantly greater in those younger, as compared with those older, than the median age (25.3 years). The rate of total cartilage thickness change did not differ significantly between the first 2 years and the later 3 years. However, the maximal annualized subregional cartilage loss (OV1) and gain (OV16) were both significantly greater (P < 0.001 and P < 0.05, respectively) during the earlier interval than during the later interval (-115 versus -54 μm [OV1] and 116 versus 69 μm [OV16]).
Cartilage thickening was observed over 5 years following ACL injury, particularly in the medial femorotibial compartment and in younger subjects. Major perturbations in cartilage homeostasis were seen over the first 2 years after ACL rupture, with simultaneous subregional thinning and thickening occurring within the same cartilage plate or compartment.
前交叉韧带（ACL）断裂会增加患骨关节炎的风险。本研究旨在探讨 ACL 断裂后 5 年内软骨厚度的变化。
共纳入 121 名来自 Knee ACL，非手术与手术治疗（KANON）研究的急性创伤性 ACL 断裂的年轻活跃成年人（年龄 18-35 岁；26%为女性）。在 ACL 断裂后 4 周内（基线）和 2 年及 5 年随访时获取矢状面磁共振成像。对内侧和外侧股胫关节软骨进行分割（对采集顺序进行盲法），并计算 16 个股胫关节分区的平均软骨厚度。总股胫关节软骨厚度变化是主要分析重点。最大分区平均软骨厚度损失（有序值 1 [OV1]）和增加（有序值 16 [OV16]），无论其在个体膝关节中的具体位置如何，均为次要分析重点。
总体而言，5 年内股胫关节软骨厚度每年增加 31μm（95%置信区间 18，44）。男性和女性的增加情况相似，且比中位数年龄（25.3 岁）年轻的患者比年龄较大的患者增加更明显。总软骨厚度变化率在最初 2 年和之后 3 年之间没有显著差异。然而，最大年度分区软骨损失（OV1）和增加（OV16）在前 2 年期间均显著大于后 3 年（分别为 P < 0.001 和 P < 0.05）（-115 对-54μm [OV1]和 116 对 69μm [OV16]）。
ACL 损伤后 5 年内观察到软骨增厚，尤其是在内侧股胫关节分区和年轻患者中。ACL 断裂后最初 2 年内观察到软骨内稳态的重大波动，同一软骨板或分区内同时出现分区变薄和增厚。
