Department of Medical Imaging, Mount Sinai Hospital and University Health Network, University of Toronto, Toronto, Ontario, Canada.
Radiology. 2010 Apr;255(1):108-16. doi: 10.1148/radiol.09091119.
To determine the frequency of imaging findings and complications related to bioabsorbable femoral cross pins at follow-up magnetic resonance (MR) imaging studies after anterior cruciate ligament (ACL) reconstruction and compare these MR imaging findings with clinical evaluation findings.
The institutional review board approved this retrospective study, and informed consent was waived. Follow-up MR imaging studies (average, 26 months after surgery) in 218 patients with prior ACL reconstruction were retrospectively reviewed. Cross-pin fracture, posterior transcortical breach, migration, resorption, and lateral prominence of cross pins, as well as the cross-pin angle relative to the transepicondylar line, were investigated on MR images. The clinical evaluation included Lachman, anterior drawer, and pivot shift tests, as well as assessment for joint tenderness.
Fracture, posterior transcortical breach, migration, and lateral prominence of cross pins were excluded from analysis when at least one cross pin was completely resorbed (n = 16 patients). Forty-five fractured cross pins were seen in 35 (17%) of 202 patients. The posterior femoral cortex was breached in 57 (28%) of 202 patients. Migration of fractured pin fragments occurred in 12 (6%) of 202 patients. There was a significant relationship between fractures and posterior breach of cross pins (P = .001), as well as between cross-pin angles and fractures (P = .002). Both cross pins were completely resorbed in 12 (6%) of 218 patients (average time since surgery, 53 months; range, 8-92 months). No significant association was found between any MR imaging finding related to cross pins and clinical test findings.
Fracture and posterior transcortical breach of bioabsorbable femoral cross pins, commonly seen at follow-up MR imaging studies, do not correlate with clinical findings of joint instability or pain. Posteriorly angulated cross pins and posterior transcortical breach are significantly associated with cross-pin fractures.
在 ACL 重建后随访的磁共振成像（MR）研究中，确定与生物可吸收股骨交叉钉相关的影像学表现和并发症的频率，并将这些 MR 成像结果与临床评估结果进行比较。
本回顾性研究经机构审查委员会批准，且豁免了知情同意。回顾性分析了 218 例 ACL 重建后患者的随访 MR 成像研究（平均术后 26 个月）。在 MR 图像上研究了交叉钉的骨折、后皮质穿透、迁移、吸收和交叉钉的外侧突出，以及交叉钉相对于髁间线的角度。临床评估包括 Lachman、前抽屉和枢轴转移试验，以及关节压痛评估。
当至少一个交叉钉完全吸收时（n = 16 例患者），排除了交叉钉的骨折、后皮质穿透、迁移和外侧突出进行分析。在 202 例患者中的 35 例（17%）中发现了 45 个骨折的交叉钉。在 202 例患者中，有 57 例（28%）后股骨皮质穿透。在 202 例患者中，有 12 例（6%）发生了骨折钉碎片的迁移。交叉钉的骨折与后皮质穿透之间存在显著相关性（P =.001），交叉钉角度与骨折之间也存在显著相关性（P =.002）。在 218 例患者中，有 12 例（6%）的双侧交叉钉完全吸收（平均手术时间 53 个月，范围 8-92 个月）。没有发现任何与交叉钉相关的影像学表现与临床检查结果之间存在显著关联。
生物可吸收股骨交叉钉在随访的 MR 成像研究中常见的骨折和后皮质穿透与关节不稳定或疼痛的临床发现无关。向后成角的交叉钉和后皮质穿透与交叉钉骨折显著相关。
