Magnetic Resonance Imaging Assessment of the Femoral Tunnel Position in Medial Patellofemoral Ligament Reconstruction

Correct femoral tunnel position in medial patellofemoral ligament (MPFL) reconstruction is essential to maintain proper biomechanics of the patellofemoral joint throughout the range of movement. Several techniques have been described for MPFL reconstruction, however, there are few reports describing the accuracy of femoral tunnel positioning assessed postoperatively. Ten patients having recurrent patellar dislocation with MPFL reconstruction performed in our centre from 2009 to 2013 were analysed. Femoral tunnel position was guided by intraoperative X-ray with landmarks described by Schottle et al, 2007. Postoperative magnetic resonance imaging (MRI) was performed on both knees, and femoral tunnel was assessed with reference to the femoral origin of the MPFL in the nonoperated side. All cases showed an intact MPFL graft, with the majority demonstrating satisfactory femoral tunnel position based on postoperative MRI. MPFL reconstruction with anatomic positioning of the femoral tunnel guided by intraoperative X-ray showed satisfactory accuracy in postoperative MRI results, indicating that a well-positioned MPFL graft results in better clinical outcomes. 在內側髕韌帶（MPFL）重建手術中，正確的股骨隧道位置是確保髕股關節在活動時，有正常生物力學的關鍵。雖然文獻上有幾種MPFL重建的技術，但是僅少數報告描述手術後股骨隧道位置的準確度。 我們分析了十名因復發性髕骨脫位，於2009 - 2013年在我們的中心進行MPFL重建手術的病人。手術中應用了X光和由PB Schottle等人描述的解剖標誌來決定股骨隧道的位置。手術後病人接受兩邊膝蓋的磁共振掃瞄MRI，並用非手術那邊MPFL的股骨原點來評估手術邊的股骨隧道位置是否準確。 術後MRI顯示所有病例中的MPFL接技（graft）完整，股骨隧道的位置大部分令人滿意。 在MPFL重建手術中，用術中X光引導和解剖標誌來決定股骨隧道的位置，有不錯的準確度。一個放在準確位置的MPFL graft，有較好的臨床效果。