Department of Orthopedic Surgery, Kyung Hee University Hospital, Seoul, Republic of Korea.
Department of Orthopedic Surgery, National Medical Center, Seoul, Republic of Korea.
Am J Sports Med. 2023 Apr;51(5):1194-1201. doi: 10.1177/03635465231156621. Epub 2023 Mar 16.
Recent biomechanical studies have reported that stress on the posterior cruciate ligament (PCL) graft increases as the posterior tibial slope (PTS) decreases (flattened) in knees with single-bundle (SB) and double-bundle PCL reconstruction. Clinical studies of SB PCL reconstruction have shown that a flattened PTS is associated with a lesser reduction in posterior tibial translation. There is no long-term study on the clinical outcomes and graft survival rates of SB PCL reconstruction based on the medial and lateral PTSs measured on magnetic resonance imaging.
Flattened medial and lateral PTSs are associated with poor clinical outcomes and graft survival rates at a minimum 10-year follow-up after SB PCL reconstruction.
Cohort study; Level of evidence, 3.
In this cohort study, we retrospectively reviewed 46 patients (mean age, 28.8 ± 9.9 years) who underwent primary SB PCL reconstruction between 2000 and 2009. They were followed up for a minimum of 10 years. The medial and lateral PTSs were measured on preoperative magnetic resonance imaging. As a previous study reported that a steeper medial or lateral PTS showed a higher risk of anterior tibial translation at thresholds of 5.6° and 3.8°, respectively, the patients were divided into 2 groups based on the cutoff values of both the medial (≤5.6° vs >5.6°) and lateral (≤3.8° vs >3.8°) PTSs. Clinical scores (International Knee Documentation Committee subjective score, Lysholm score, and Tegner activity score), radiological outcomes (side-to-side difference [SSD] on stress radiography and osteoarthritis progression), and graft survival rates were compared between the groups at the last follow-up.
All clinical scores and the progression of osteoarthritis demonstrated no significant difference between the 2 subgroups of both the medial and lateral PTS groups. The mean SSD on stress radiography after SB PCL reconstruction was significantly greater in patients with a medial PTS ≤5.6° than in patients with a medial PTS >5.6° (8.4 ± 3.9 vs 5.1 ± 2.9 mm, respectively; = .030), while the lateral PTS subgroups after SB PCL reconstruction demonstrated no significant difference. The minimum 10-year graft survival rate was significantly lower in patients with a medial PTS ≤5.6° (68.4% vs 92.6%, respectively; = .029) and a lateral PTS ≤3.8° (50.0% vs 91.7%, respectively; = .001).
A flattened medial PTS (≤5.6°) was associated with an increased SSD on stress radiography, and both flattened medial (≤5.6°) and lateral (≤3.8°) PTSs resulted in lower graft survival rates at a minimum 10-year follow-up after primary SB PCL reconstruction.
最近的生物力学研究表明，在单束（SB）和双束前交叉韧带（PCL）重建的膝关节中，随着胫骨后倾角（PTS）的降低（变平），PCL 移植物上的应力增加。SB PCL 重建的临床研究表明，平胫骨后倾角与胫骨后移的减少程度较小有关。目前还没有基于 MRI 测量的内侧和外侧 PTS 对 SB PCL 重建的临床结果和移植物存活率进行的 10 年以上的长期研究。
在 SB PCL 重建后至少 10 年的随访中，平的内侧和外侧 PTS 与较差的临床结果和移植物存活率相关。
队列研究；证据水平，3 级。
在这项队列研究中，我们回顾性分析了 2000 年至 2009 年间接受原发性 SB PCL 重建的 46 例患者（平均年龄 28.8 ± 9.9 岁）。他们的随访时间至少为 10 年。术前磁共振成像测量了内侧和外侧 PTS。由于之前的一项研究报告称，在分别为 5.6°和 3.8°的阈值下，更陡峭的内侧或外侧 PTS 显示出更高的前胫骨平移风险，因此根据内侧（≤5.6°与>5.6°）和外侧（≤3.8°与>3.8°）PTS 的截止值将患者分为 2 组。在最后一次随访时，比较了两组之间的临床评分（国际膝关节文献委员会主观评分、Lysholm 评分和 Tegner 活动评分）、影像学结果（应力位 X 线片上的侧-侧差异[SSD]和骨关节炎进展）和移植物存活率。
内侧和外侧 PTS 两组的所有临床评分和骨关节炎进展均无显著差异。与 PTS 内侧>5.6°的患者相比，接受 SB PCL 重建的患者 PTS 内侧≤5.6°的 SSD 明显更大（分别为 8.4 ± 3.9 与 5.1 ± 2.9mm； =.030），而接受 SB PCL 重建的外侧 PTS 亚组则无显著差异。与 PTS 内侧>5.6°的患者相比，接受 SB PCL 重建的患者 PTS 内侧≤5.6°的最小 10 年移植物存活率明显更低（分别为 68.4%与 92.6%； =.029），而 PTS 外侧≤3.8°的患者最小 10 年移植物存活率明显更低（分别为 50.0%与 91.7%； =.001）。
平的内侧 PTS（≤5.6°）与应力位 X 线片上的 SSD 增加有关，平的内侧（≤5.6°）和外侧（≤3.8°）PTS 均导致原发性 SB PCL 重建后至少 10 年的移植物存活率降低。
