对于患有股骨远端恶性骨肉瘤的患者而言，人们担心在从肿瘤的后部软组织中分离膝窝血管时，根据后部软组织肿块的程度，可能无法获得充分的切除间隙。外科医生在决定是否在与后部肿瘤直接接触的患者中分离膝窝血管时，缺乏指导性信息，以判断与膝窝血管与肿瘤间有正常组织的患者相比，是否存在与局部复发风险增加的关联（①）。在这种骨肉瘤解剖位置的患者中，肿瘤切除类型与胸部转移和总体生存率之间是否有关联（②）？我们对病人数据库进行了回顾性研究。从1994年8月1日至2019年12月31日，筛选出所有接受化疗和手术治疗的常规股骨远端骨肉瘤患者。对于存活的患者，要求至少进行2年的随访。共有545名符合这些标准的患者。我们排除了7%（37名患者）没有后部软组织肿块，9%（51名患者）有转移，0.7%（四名患者）有多发部位的骨肉瘤，1%（五名患者）死于化疗并发症，6%（30名患者）失访。总计418名患者（211名男性，207名女性）符合本研究条件。患者的平均年龄为17±6.6岁。所有患者均接受常规分期（平片、MRI、胸部CT和骨扫描）和术前化疗。我们依据膝窝血管与外骨肿瘤的关系将患者分为两组。两位高级作者分别对轴向MRI切片（T1、带对比剂的T1、T2和短时参数反转恢复图像）进行了分析。争议由高级骨骼肌肉放射科医生解决，并由患者的手术报告进行确认。第一组包括229名患者，膝窝血管与肿瘤之间存在明确的层面。所有患者均接受肢体保留治疗。第二组包括189名患者，膝窝血管与肿瘤粘连。该组继续细分为2a组（膝窝血管进行分离并进行肢体保留治疗；血管在某些区域与肿瘤之间剥离动脉外膜）和2b组（未试图分离血管，进行截肢或旋转成形术）。在进行旋转成形术时，血管会被切除和再吻合。对于第一组，进行肢体保留治疗的决定不容置疑。然而，在第二组中的患有粘连血管的患者中，教案委员会会进行决策。对于完全包裹血管或神经、非愈合的病理性骨折和肿瘤穿越皮肤的破溃的肿瘤，采用截肢或旋转成形术进行治疗。对于粘连但未被包裹的肿瘤，患者被提供肢体保留治疗。这通常是与患者共同决策的结果。我们对切除标本进行病理学评估，以评估边缘和肿瘤坏死。进行膝窝血管解剖术，将其从外膜上剥离的患者（2a组）的局部复发生存率（5年生存率为68% [95%CI 57% to 78%]）低于没有粘连肿瘤的患者（1组：96% [95%CI 93% to 99%]）和进行截肢或旋转成形术的粘连肿瘤患者（2b组：99% [95%CI 96 to 100]; p<0.01）。142名患者出现胸部转移。2a组胸部转移比例（59% [101中60例]）高于1组（24% [229中55例]）和2b组（31% [88中27例]; p<0.01）。5年总生存率在进行膝窝血管解剖术，将其从外膜上剥离的患者（2a组）中（51% [95%CI 40% to 63%]）低于没有粘连肿瘤的患者（1组：78% [95%CI 72% to 84%]）和进行截肢或旋转成形术的粘连肿瘤患者（2b组：71% [95%CI 60% to 82%]; p<0.01）。根据这些结果，在进行股骨远端骨肉瘤的肢体保留手术，并且膝窝血管粘连时，保留外膜间隙与局部复发的发生率增加和总体生存率较差相关。外科医生应该避免分离这些粘连的血管，或至少与患者讨论预期结果。未来的研究可以针对血管切除和血流重建在骨肉瘤管理中的结果进行研究。三级，治疗研究。版权所有于2023年骨科医师协会。

In patients who have osteosarcoma of the distal femur, there is concern that when dissecting the popliteal vessels from the posterior soft tissue extent of the tumor, a less-than-wide margin of resection may be achieved depending on the extent of the posterior soft tissue mass. Surgeons have little information to guide them when deciding whether dissecting the popliteal vessels in a patient in whom the vessels are in direct contact with a posterior mass will result in an increased likelihood of local recurrence compared with patients in whom the popliteal vessels are not in contact with the tumor mass.(1) Is dissecting the adherent popliteal artery and vein away from the posterior soft tissue extent of a distal femoral osteosarcoma by stripping them from their adventitia associated with an increased risk of local recurrence compared with patients in whom there is normal tissue between the tumor and vessels? (2) Is there an association with the type of tumor resection and the development of chest metastases and overall survivorship in this anatomic location?We retrospectively studied our patient database. From August 1, 1994, until December 31, 2019, all patients with conventional distal femoral osteosarcomas treated with chemotherapy and surgery were identified. A minimum of 2 years of follow-up was required for patients who were alive. A total of 545 patients matched these criteria. We excluded 7% (37 patients) who did not have a posterior soft tissue mass, 9% (51 patients) who has metastases, 0.7% (four patients) who had osteosarcomas in multiple sites, 1% (five patients) who died of chemotherapy complications, and 6% (30 patients) who were lost to follow-up. A total of 418 patients (211 men and 207 women) were eligible for this study. The mean age of the patients was 17 ± 6.6 years. All patients underwent routine staging (plain radiographs, MRI, chest CT, and bone scan) and received preoperative chemotherapy. The patients were divided into two groups according to the relationship between the popliteal vessels and the posterior extent of the extraosseous tumor. Axial MRI slices (T1, T1 with contrast, T2, and short tau inversion recovery) were analyzed separately by the two senior authors. Disputes were settled by a senior musculoskeletal radiologist and confirmed by the patient's operative report. In Group 1, which included 229 patients, there was a clear plane between the popliteal vessels and tumor. All patients underwent limb salvage. In Group 2, which had 189 patients, the popliteal vessels adhered to the tumor. This group was further subdivided into Groups 2a (patients in whom the vessels were dissected and limb salvage was performed; dissection of the popliteal vessels from the tumor entailed stripping the vessels from its adventitia in some areas) and 2b (patients in whom no attempt was made to dissect the vessels, and amputation or rotationplasty was performed). When rotationplasty was performed, the vessels were resected and reanastomosed. The decision to perform limb salvage in Group 1 was not debatable; however, in patients in Group 2, who had adherent vessels, the decision was made by the tumor board. Tumors with complete encasement of the vessels or nerves, nonunited pathologic fractures, and fungating of the tumor through the skin were treated by amputation or rotationplasty. Patients with tumors with adherent vessels that were not encased were offered limb salvage. This was often a shared decision with the patient. We performed a pathologic evaluation of the resected specimens to evaluate margins and tumor necrosis in all specimens.Local recurrence-free survivorship was worse in patients with adherent tumors who underwent dissection of the vessels by stripping them from their adventitia (Group 2a; 68% at 5 years [95% CI 57% to 78%]) than in those without adherent tumors (Group 1: 96% [95% CI 93% to 99%]) and patients with adherent tumors who had amputation or rotationplasty (Group 2b: 99% [95% CI 96 to 100]; p < 0.01). Chest metastases developed in 142 patients. The proportion of chest metastases was higher in Group 2a (59% [60 of 101]) than in Group 1 (24% [55 of 229]) and Group 2b (31% [27 of 88]; p < 0.01). Five-year overall survivorship was worse in patients with adherent tumors who underwent dissection of the vessels by stripping them from their adventitia (Group 2a: 51% at 5 years [95% CI 40% to 63%]) than in those without adherent tumors (Group 1: 78% [95% CI 72% to 84%]) and patients with adherent tumors who had amputation or rotationplasty (Group 2b: 71% [95% CI 60% to 82%]; p < 0.01).In light of these findings, when performing limb salvage for distal femoral osteosarcoma with adherent vessels, leaving an adventitial margin is associated with an increase in the incidence of local recurrence and poorer overall survivorship. Surgeons should refrain from dissecting these adherent vessels or at minimum discuss the expected outcomes with the patient. Future studies could target the outcome of vascular resection and bypass graft in the management of osteosarcoma.Level III, therapeutic study.Copyright © 2023 by the Association of Bone and Joint Surgeons.