Division of Sports Medicine, Department of Orthopedic Surgery, Chicago, Illinois, U.S.A.
Orthopaedic Biomechanics laboratory, Rush University Medical Center, Chicago, Illinois, U.S.A.
Arthroscopy. 2020 Nov;36(11):2900-2908. doi: 10.1016/j.arthro.2020.07.007. Epub 2020 Jul 28.
To analyze the topographic matching of oblong osteochondral allografts to treat large oval medial femoral condyle (MFC) lesions using computer simulation models. The secondary objective was to determine whether lateral femoral condyle (LFC) grafts would have a similar surface matching when compared with MFC grafts in this setting.
Human femoral hemicondyles (10 MFCs, 7 LFCs) underwent 3-dimensional computed tomography. Models were created from computed tomography images and exported into point-cloud models. Donor-recipient matches with large condylar width mismatch were excluded. The remaining specimen were divided into 3 donor-recipient groups with 2 defect sizes (17 × 30 mm and 20 × 30 mm): 20 MFC donor (MFCd)-MFC recipient (MFCr), 27 ipsilateral LFC donor (LFCd)-MFCr, and 26 contralateral LFCd-MFCr. Grafts were optimally virtually aligned with the MFCr defect. Mismatch of the articular cartilage and subchondral bone surfaces between the graft and the defect and articular step-off were calculated.
MFCd grafts resulted in articular cartilage surface mismatch and peripheral step of less than 0.5 mm for both defect sizes. The subchondral bone surface mismatch was significantly greater than the articular cartilage surface mismatch (P < .01) in both defect sizes). Conversely, the ipsilateral and contralateral LFCd grafts resulted in significantly greater articular cartilage surface mismatch and step-off for both defect sizes when compared to MFCd grafts (P < .01).
Oblong MFC allografts provide acceptable topographic matching for large oval MFC lesions when condylar width differences are minimized. However, concern exists in using oblong LFC allografts for MFC defects, as this can result in increased peripheral step-off and surface mismatch.
These data reinforce the ability to use oblong MFC osteochondral allograft for treating oval cartilage lesions of the MFC when condylar width is considered. Although other studies have demonstrated LFCs can be used to treat circular defects on the MFC, this may not be true for oblong grafts.
通过计算机模拟模型分析长椭圆形同种异体骨软骨移植治疗大面积椭圆形股骨内侧髁（MFC）病变的表面匹配情况。次要目的是确定在这种情况下，与 MFC 移植物相比，外侧髁（LFC）移植物是否具有相似的表面匹配。
对 10 个 MFC 和 7 个 LFC 进行人体股骨半髁 3 维计算机断层扫描。从计算机断层扫描图像创建模型，并将其导出到点云模型中。排除与大髁宽度不匹配的供体-受体匹配。其余标本根据供体-受体匹配分为 3 组，每组有 2 种不同的缺损大小（17×30mm 和 20×30mm）：20 个 MFC 供体（MFCd）-MFC 受体（MFCr）、27 个同侧 LFC 供体（LFCd）-MFCr 和 26 个对侧 LFCd-MFCr。将移植物与 MFCr 缺损进行最佳虚拟对齐。计算移植物与缺损之间的关节软骨和软骨下骨表面的不匹配以及关节台阶。
对于两种缺损大小，MFCd 移植物的关节软骨表面不匹配和外周台阶均小于 0.5mm。在两种缺损大小中，软骨下骨表面不匹配均明显大于关节软骨表面不匹配（P<.01）。相反，同侧和对侧 LFCd 移植物的关节软骨表面不匹配和台阶对于两种缺损大小均明显大于 MFCd 移植物（P<.01）。
当髁宽度差异最小化时，长椭圆形 MFC 同种异体骨移植可为大面积椭圆形 MFC 病变提供可接受的表面匹配。然而，对于使用长椭圆形 LFC 同种异体骨移植治疗 MFC 缺损，存在一定的担忧，因为这可能导致外周台阶增加和表面不匹配。
这些数据强化了在考虑髁宽度的情况下，使用长椭圆形 MFC 骨软骨同种异体移植治疗 MFC 椭圆形软骨病变的能力。尽管其他研究表明 LFC 可用于治疗 MFC 上的圆形缺损，但对于长椭圆形移植物可能并非如此。
