Department of Functional Reconstruction for the Knee Joint, Faculty of Medicine, Hokkaido University, Sapporo, Japan.
Centre for Sports Medicine, Hokkaido University Hospital, Sapporo, Japan.
Am J Sports Med. 2021 May;49(6):1561-1569. doi: 10.1177/03635465211002537. Epub 2021 Apr 2.
The effect of high tibial osteotomy (HTO) on the stress distribution across the knee joint is not completely understood. Subchondral bone density is considered to reflect the pattern of stress distribution across a joint surface.
To assess the distribution of subchondral bone density across the proximal tibia in nonarthritic knees and in the knees of patients with osteoarthritis (OA) before and after HTO.
Cohort study; Level of evidence, 3.
We retrospectively collected radiological and computed tomography data from 16 patients without OA (control group) and 17 patients with OA. Data from the OA group were collected before and 1.5 years after HTO. Subchondral bone density of the proximal tibia was assessed with computed tomography-osteoabsorptiometry. The locations and percentages represented by high-density areas (HDAs) on the articular surface were quantitatively analyzed.
The ratio of the HDA of the medial compartment to the total HDA (medial ratio) was significantly higher in the preoperative OA group (mean, 80.1%) than in the control group (61.3%) ( < .001). After HTO, the medial ratio decreased significantly to 75.1% ( = .035 in comparison with preoperative values) and was significantly correlated with the hip-knee-ankle angle in both groups: control ( = -0.551; = .033) and OA ( = -0.528; = .043). The change in medial ratio after HTO was significantly correlated with the change in hip-knee-ankle angle ( = 0.587; = .035). In the medial compartment, the HDA in the most lateral region of 4 subregions increased after HTO, but that in 3 medial subregions decreased.
In this exploratory study, HTO shifted the HDA of the medial compartment of the proximal tibial articular surface toward the lateral compartment. In contrast, the HDA of the most lateral region of the medial compartment increased after HTO. This change in subchondral bone density may result from the change in stress distribution.
高位胫骨截骨术（HTO）对膝关节内的应力分布的影响尚未完全阐明。软骨下骨密度被认为反映了关节表面的应力分布模式。
评估非骨关节炎膝关节和骨关节炎（OA）患者 HT0 前后膝关节软骨下骨密度在胫骨近端的分布。
队列研究；证据水平，3 级。
我们回顾性地从 16 例无 OA（对照组）和 17 例 OA 患者中收集放射学和计算机断层扫描数据。OA 组的数据在 HT0 前和 1.5 年后收集。使用计算机断层扫描-骨吸收测量法评估胫骨近端软骨下骨密度。对关节表面高密度区（HDA）的位置和百分比进行定量分析。
术前 OA 组（平均 80.1%）的内侧间室 HDA 与总 HDA 的比值（内侧比值）明显高于对照组（61.3%）（<.001）。HT0 后，内侧比值显著下降至 75.1%（与术前值相比，=.035），且与两组的髋膝踝角均显著相关：对照组（= -0.551；=.033）和 OA 组（= -0.528；=.043）。HT0 后内侧比值的变化与髋膝踝角的变化显著相关（=0.587；=.035）。在内侧间室中，4 个亚区最外侧区域的 HDA 在 HT0 后增加，而 3 个内侧亚区的 HDA 减少。
在这项探索性研究中，HTO 将胫骨近端关节表面内侧间室的 HDA 向外侧间室转移。相反，HT0 后内侧间室最外侧区域的 HDA 增加。软骨下骨密度的这种变化可能是由于应力分布的变化所致。
