Choi Yun Seong, Yoon Jung-Ro, Shin Young-Bin, Lee Seung Hoon
Department of Orthopaedic Surgery, Veterans Health Service Medical Center.
Department of Orthopaedic Surgery, Veterans Health Service Medical Center.
Knee. 2024 Dec;51:173-180. doi: 10.1016/j.knee.2024.09.008. Epub 2024 Sep 30.
This study investigated bone mineral density (BMD) around the knee joint to clarify the mechanism by which tibia deformation exceeds that of the femur in patients with end-stage knee osteoarthritis (KOA).
We retrospectively analyzed 193 patients who underwent total knee arthroplasty for end-stage KOA with varus alignment. Preoperative T-score of the femur neck and femur total using dual-energy X-ray absorptiometry (DXA) and hounsfield units (HU) of the distal femur and proximal tibia using computed tomography (CT) were measured to asess the BMD. HU was measured by dividing the femur and tibia into medial, lateral, and total parts, respectively. Patients with medial proximal tibial angle (MPTA) ≥ 85° were considered 'group 1', and MPTA < 85° were 'group 2'. The HU between femur and tibia were compared in group 1. T-score, HU, and HU difference between group 1 and group 2 were compared.
The HU of the proximal tibia was lower than that of the distal femur (femur lateral > femur medial > tibia medial > tibia lateral). T-score (femur neck, femur total) and HU (femur lateral, femur total, tibia lateral) were lower in group 2 than in group 1. There was no difference in femur-tibia HU difference between groups.
The medial tibia collapse more than the medial femur in varus endstage KOA was associated with the lower BMD of the proximal tibia than that of the distal femur, and the MPTA collapse was affected by the absolute value of BMD rather than by the femur-tibia BMD difference.
本研究调查了膝关节周围的骨密度（BMD），以阐明终末期膝关节骨关节炎（KOA）患者胫骨变形超过股骨的机制。
我们回顾性分析了193例行全膝关节置换术的终末期内翻型KOA患者。采用双能X线吸收法（DXA）测量术前股骨颈和全股骨的T值，采用计算机断层扫描（CT）测量股骨远端和胫骨近端的骨密度单位（HU）以评估骨密度。HU分别通过将股骨和胫骨分为内侧、外侧和整体部分来测量。胫骨近端内侧角（MPTA）≥85°的患者被视为“第1组”，MPTA＜85°的患者为“第2组”。比较第1组股骨和胫骨之间的HU。比较第1组和第2组之间的T值、HU和HU差值。
胫骨近端的HU低于股骨远端（股骨外侧＞股骨内侧＞胫骨内侧＞胫骨外侧）。第2组的T值（股骨颈、全股骨）和HU（股骨外侧、全股骨、胫骨外侧）低于第1组。两组之间股骨-胫骨HU差值无差异。
内翻型终末期KOA中，胫骨内侧比股骨内侧塌陷更严重，这与胫骨近端骨密度低于股骨远端有关，且MPTA塌陷受骨密度绝对值影响，而非受股骨-胫骨骨密度差值影响。
