Department of Orthopaedic Surgery, University of Pittsburgh Medical Center, UPMC Rooney Sports Complex, 3200 South Water Street, Pittsburgh, PA, 15203, USA.
Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Knee Surg Sports Traumatol Arthrosc. 2023 Jul;31(7):2998-3006. doi: 10.1007/s00167-023-07312-3. Epub 2023 Jan 12.
This study aimed to evaluate posterolateral tibial plateau impaction fractures and how they contribute to rotatory knee laxity using quantitative pivot shift analysis. It was hypothesised that neither the presence of nor the degree of involvement of the plateau would affect rotatory knee laxity in the ACL-deficient knee.
A retrospective review of prospectively collected data on 284 patients with complete anterior cruciate ligament (ACL) injuries was conducted. Posterolateral tibial plateau impaction fractures were identified on preoperative MRI. The patients were divided into two cohorts: "fractures" or "no fractures". The cohort with fractures was further categorised based on fracture morphology: "extra-articular", "articular-impaction", or "displaced-articular fragment". All data were collected during examination under anaesthesia performed immediately prior to ACL reconstruction. This included a standard pivot shift test graded by the examiner and quantitative data including anterior tibial translation (mm) via Rolimeter, quantitative pivot shift (QPS) examination (mm) via PIVOT tablet technology, and acceleration (m/sec) during the pivot shift test via accelerometer. Quantitative examinations were compared with the contralateral knee.
There were 112 patients with posterolateral tibial plateau impaction fractures (112/284, 39%). Of these, 71/112 (63%) were "extra-articular", 28/112 (25%) "articular-impaction", and 13/112 (12%) "displaced-articular". Regarding the two groups with or without fractures, there was no difference in subjective pivot shift (2 ± 0 vs 2 ± 0, respectively, n.s.), QPS (2.4 ± 1.6 mm vs 2.7 ± 2.2 mm, respectively, n.s.), anterior tibial translation measurements (6 ± 3 mm vs 5 ± 3 mm, respectively, n.s.), or acceleration of the knee during the pivot (1.7 ± 2.3 m/s vs 1.8 ± 3.1 m/s, respectively, n.s.). When the fractures were further subdivided, subgroup analysis revealed no significant differences noted in any of the measured examinations between the fracture subtypes.
This study showed that the posterolateral tibial plateau impaction fractures are commonly encountered in the setting of ACL tears; however, contrary to previous reports, they do not significantly increase rotatory knee laxity. This suggests that this type of concomitant injury may not need to be addressed at the time of ACL reconstruction.
Level III.
本研究旨在通过定量旋转试验分析评估后外侧胫骨平台挤压骨折及其对膝关节旋转松弛的影响。我们假设，ACL 缺失膝关节中，平台的存在与否及其受累程度均不会影响膝关节的旋转松弛度。
对 284 例完全前交叉韧带（ACL）损伤患者的前瞻性数据进行回顾性分析。术前 MRI 识别后外侧胫骨平台挤压骨折。将患者分为两组：“骨折”或“无骨折”。骨折组进一步根据骨折形态分为：“关节外”、“关节撞击”或“关节内移位骨折块”。所有数据均在 ACL 重建前进行的麻醉下检查中收集。这包括由检查者进行的标准旋转试验和通过 Rolimeter 进行的前胫骨平移（mm）、通过 PIVOT tablet 技术进行的定量旋转试验（QPS）检查（mm）和通过加速度计进行的旋转试验期间的加速度（m/sec）。定量检查与对侧膝关节进行比较。
112 例（112/284，39%）患者存在后外侧胫骨平台挤压骨折。其中，71/112（63%）为“关节外”，28/112（25%）为“关节撞击”，13/112（12%）为“关节内移位骨折块”。对于有或无骨折的两组，主观旋转试验（分别为 2±0 和 2±0，n.s.）、QPS（分别为 2.4±1.6 和 2.7±2.2，n.s.）、前胫骨平移测量（分别为 6±3 和 5±3，n.s.）或膝关节旋转期间的加速度（分别为 1.7±2.3 和 1.8±3.1，n.s.）无差异。当骨折进一步细分时，亚组分析显示，在骨折亚组之间，任何测量检查均未发现显著差异。
本研究表明，ACL 撕裂时后外侧胫骨平台挤压骨折很常见；然而，与先前的报告相反，它们并不会显著增加膝关节的旋转松弛度。这表明这种类型的伴随损伤可能不需要在 ACL 重建时处理。
III 级。
