MPFL reconstruction and tibial tubercle osteotomy for treating recurrent instability of patella associated with high grade trochlear dysplasia

The aim of this study is to observe the results and complications of medial patellofemoral ligament reconstruction with a modified Fulkerson osteotomy, in patients with recurrent instability of patella associated with high-grade trochlear dysplasia. A minimal lateral release was performed whenever tight lateral structures leading to an excessive patellar tilt were encountered after completion of bony realignment. We hypothesized that MPFL reconstruction with modified Fulkerson osteotomy would efficiently treat patellar instability associated with high grade trochlear dysplasia, by realigning the extensor mechanism and recreating the check-rein effect of the MPFL on the medial side. A prospective observational study of 26 knees (21 patients) who underwent simultaneous MPFL reconstruction and distal realignment with modified Fulkerson osteotomy from June 2014 to February 2019. Surgery was performed at a single center by the senior author. Radiological outcomes were measured by X-ray images at monthly follow up and an MRI scan at 6 months post-surgery to re-evaluate CD ratio, TT-TG distance and patellar tilt. Patient outcomes were measured with Kujala, Lysholm & International Knee Documentation Committee (IKDC) subjective knee evaluation form preoperatively, at 6 months, 1 year and 2 year follow up visits.本研究旨在观察复发性髌骨不稳合并重度滑车发育不良患者，采用改良Fulkerson截骨联合髌股内侧韧带（medial patellofemoral ligament, MPFL）重建术的治疗效果与并发症。当骨性重排完成后，若发现外侧软组织紧张导致髌骨过度倾斜，则实施有限外侧松解术。本研究假设：通过重新调整伸肌装置的力线，并重建髌股内侧韧带在内侧的缰绳约束效应，改良Fulkerson截骨联合MPFL重建术可有效治疗合并重度滑车发育不良的髌骨不稳。本研究为前瞻性观察性研究，纳入2014年6月至2019年2月期间，由同一位资深主刀医师在单中心完成手术的21例患者共26个膝关节，所有患者均接受改良Fulkerson截骨联合MPFL重建的远端力线矫正手术。影像学结局通过术后每月随访的X线影像，以及术后6个月的磁共振成像（magnetic resonance imaging, MRI）扫描进行评估，以重新评估CD比值（CD ratio）、胫骨结节-股骨滑车沟距离（TT-TG distance）及髌骨倾斜角。患者临床结局分别于术前、术后6个月、1年及2年随访时，采用Kujala评分、Lysholm评分及国际膝关节文献委员会（International Knee Documentation Committee, IKDC）主观膝关节评估量表进行测评。