Slevin Omer, Schmid Florian A, Schiapparelli Filippo-Franco, Rasch Helmut, Amsler Felix, Hirschmann Michael T
Department of Orthopedic Surgery, Meir General Hospital, Kfar Saba, Israel.
Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland (Bruderholz, Liestal, Laufen), 4101, Bruderholz, Switzerland.
Knee Surg Sports Traumatol Arthrosc. 2017 Nov;25(11):3605-3610. doi: 10.1007/s00167-017-4627-2. Epub 2017 Jun 26.
As patellar tracking and loading is influenced by tibial tuberosity and trochlear groove (TT-TG) distance, patellar height, thickness and tilt as well as TKA component position, it was our hypothesis that these parameters significantly correlate with patellar BTU intensity and localization in SPECT/CT. The purpose of the study was to investigate whether TKA component position as well as the height, thickness and tilt of the unresurfaced patella influences the intensity and the distribution pattern of BTU in SPECT/CT.
A total of 62 consecutive patients who underwent primary TKA without patellar resurfacing were prospectively included. Demographic data such as age, gender, side and type of primary TKA were noted. All patients underwent clinical and radiological examination in a specialized knee clinic, including standardized radiographs (anterior-posterior and lateral weight bearing, patellar skyline view) and Tc-99m-HDP-SPECT/CT before, 12 and 24 months after TKA. SPECT/CT images were analysed on 3D reconstructed images. Rotational, sagittal and coronal position of the tibial and femoral TKA components was assessed using a previously validated analysis software. Measurements of BTU including intensity and anatomical distribution pattern were also performed from 3D data. The patellar height, thickness and tilt were measured, and the distance between TT and TG was measured using axial CT images. Univariate analysis was performed to identify any correlations between BTU and TKA component position and patellar measurements (p < 0.05).
The highest median BTU was measured in the superior posterior parts of the patella. A statistically significant correlation was found between valgus alignment of the femoral TKA and increased BTU at the lateral patellar regions (p < 0.05). External rotation of the tibial TKA correlated with increased BTU at the lateral superior joint adjacent part (p < 0.05). No correlation was found between the tibial TKA position (varus-valgus, anterior and posterior slope), TT-TG distance, patellar height and patellar BTU values.
A significant correlation of increased patellar BTU was found with femoral valgus TKA alignment. These findings highlight the importance of femoral TKA position in coronal plane with regard to post-operative patellar tracking. Moreover, these facts might explain anterior knee pain in unhappy TKA with femoral valgus alignment.
Diagnostic study, Level II.
由于髌股轨迹和负荷受胫骨结节与滑车沟（TT-TG）距离、髌骨高度、厚度和倾斜度以及全膝关节置换（TKA）组件位置的影响，我们的假设是这些参数与SPECT/CT中髌骨骨小梁骨单位（BTU）强度及定位显著相关。本研究的目的是调查TKA组件位置以及未进行表面置换的髌骨的高度、厚度和倾斜度是否会影响SPECT/CT中BTU的强度和分布模式。
前瞻性纳入62例连续接受初次TKA且未进行髌骨表面置换的患者。记录年龄、性别、患侧及初次TKA类型等人口统计学数据。所有患者均在专业膝关节诊所接受临床和影像学检查，包括标准化X线片（前后位和侧位负重位、髌骨轴位像）以及TKA术前、术后12个月和24个月的锝-99m-亚甲基二膦酸盐（Tc-99m-HDP）-SPECT/CT检查。在三维重建图像上分析SPECT/CT图像。使用先前验证的分析软件评估胫骨和股骨TKA组件的旋转、矢状和冠状位。还从三维数据中测量BTU，包括强度和解剖分布模式。测量髌骨高度、厚度和倾斜度，并使用轴向CT图像测量TT与TG之间的距离。进行单因素分析以确定BTU与TKA组件位置和髌骨测量值之间的任何相关性（p < 0.05）。
髌骨后上部测得的BTU中位数最高。发现股骨TKA外翻对线与髌骨外侧区域BTU增加之间存在统计学显著相关性（p < 0.05）。胫骨TKA外旋与外侧上关节相邻部位BTU增加相关（p < 0.05）。未发现胫骨TKA位置（内翻-外翻、前后倾斜度）、TT-TG距离、髌骨高度与髌骨BTU值之间存在相关性。
发现髌骨BTU增加与股骨TKA外翻对线显著相关。这些发现突出了股骨TKA在冠状面位置对于术后髌股轨迹的重要性。此外，这些事实可能解释了股骨外翻对线的不满意TKA患者的膝前疼痛。
诊断性研究，二级。
