Does Augmenting Irradiated Autografts With Free Vascularized Fibula Graft in Patients With Bone Loss From a Malignant Tumor Achieve Union, Function, and Complication Rate Comparably to Patients Without Bone Loss and Augmentation When Reconstructing Intercalary Resections in the Lower Extremity?

IF 4.2 2区 医学 Q1 ORTHOPEDICS
Arman Vahabi,Hüseyin Kaya,Bakıt Kerekulov,Ahmet Biçer,Burçin Keçeci,Dündar Sabah
{"title":"Does Augmenting Irradiated Autografts With Free Vascularized Fibula Graft in Patients With Bone Loss From a Malignant Tumor Achieve Union, Function, and Complication Rate Comparably to Patients Without Bone Loss and Augmentation When Reconstructing Intercalary Resections in the Lower Extremity?","authors":"Arman Vahabi,Hüseyin Kaya,Bakıt Kerekulov,Ahmet Biçer,Burçin Keçeci,Dündar Sabah","doi":"10.1097/corr.0000000000003599","DOIUrl":null,"url":null,"abstract":"BACKGROUND\r\nExtracorporeally irradiated autografting is a recognized technique in reconstruction after intercalary resections, but it has drawbacks such as nonunion and graft fracture. Because sterilized autografts lose some of their mechanical properties due to involvement of the cortex with tumor, the curettage, and the adverse effects of irradiation or other sterilization techniques, some have proposed adding vascularized fibula to augment the autograft. Because this potentially adds morbidity, we sought to address the value of adding vascular fibular grafts to reconstruction with irradiated autografts.\r\n\r\nQUESTIONS/PURPOSES\r\nComparing patients who received an extracorporeally radiated autograft alone with those who received such a graft augmented by a free vascularized fibular autograft: (1) Was the proportion of patients who did not achieve union by 12 months higher in the group that received the augmented (vascularized) graft? (2) Did the augmented-graft group demonstrate greater survivorship free from graft loss at 72 months than did the group receiving an irradiated graft alone? (3) Were there between-group differences in functional results? (4) Were there between-group differences in complications, defined as those substantial enough to result in further surgery?\r\n\r\nMETHODS\r\nIn our single-center study, conducted in a tertiary academic referral center, we performed a retrospective chart audit of patients undergoing intercalary resections for primary sarcomas of the femur and tibia. Between January 2002 and April 2023, three surgeons (HK, BK, DS) treated 345 patients for bone sarcoma of the femur or tibia. Of those, we considered 25% (85) treated with intercalary resection for primary bone sarcomas as potentially eligible. A further 7% (23 of 345) of patients were excluded because their reconstruction was performed using a technique other than irradiated autografts. Another 2% (6) had died prior to the minimum follow-up period of 24 months, another 1% (3) did not finish the 24-month follow-up, and 1% (3) were lost to follow-up for > 5 years, leaving 14% (50 of 345) for analysis here. Among these, 26% (13 of 50) of patients underwent reconstruction involving an extracorporeally irradiated autograft and augmentation with a vascularized fibula autograft. In the remaining 37 patients, reconstruction was performed using extracorporeally irradiated bone alone. During this period, intercalary resection was typically indicated for patients with primary bone sarcomas located in the metaphyseal or diaphyseal regions without articular involvement, provided that they demonstrated a favorable response to neoadjuvant therapy. In this predominantly young patient cohort, extracorporeally irradiated autografts were our preferred reconstruction method after sarcoma resection. Isolated extracorporeally irradiated autografts were selected for patients with radiologic evidence of adequate bone quality and preserved cortical integrity. In patients who have a tumor with extensive cortical destruction-yet still considered suitable for reconstruction after irradiation-vascularized fibular grafts were added to the irradiated autografts. In the group reconstructed with irradiated autograft alone, 54% (20 of 37) of patients were male and 46% (17) were female, with a median (range) age of 15 years (4 to 60). The diagnoses included osteosarcoma in 51% (19 of 37) of patients and Ewing sarcoma in 32% (12). The tumor was located in the tibia in 59% (22) of patients and in the femur in 41% (15). In the group receiving irradiated autograft augmented with vascularized fibula, 6 of the 13 patients were male and 7 were female, with a median (range) age of 13 years (6 to 40). Diagnoses included osteosarcoma in eight of 13 patients, Ewing sarcoma in four, and malignant mesenchymal tumor in one patient. Tumor originated from the femur in 11 patients and from the tibia in two. The two groups were similar in terms of histopathologic diagnosis, age, gender, follow-up duration, and tumor location within bone while the proportion of tumors originating from the femur was higher in the group treated with vascularized fibula augmentation (85% versus 41%; p < 0.05). Fixation technique, the ratio of the resected bone length to the entire bone, was noted using the first postoperative radiograph. Bony union, defined as bony bridging in at least three cortices, was assessed using two-plane radiographs. Patients who achieved bony union within the first 12 months without undergoing any additional surgical intervention were classified as having union. Patients whose autograft incorporation exceeded 12 months but ultimately achieved union before 15 months without the need for additional intervention were classified as having delayed union. Nonunion was defined as when patients demonstrated incomplete integration at the 15-month follow-up or when patients needed additional intervention before healing. The survival of extracorporeally irradiated autografts, free from any degree of loss (partial or complete graft loss attributed to graft fracture resorption or graft removal after infection or recurrence), was assessed using competing risk analysis, with death as a competing event at 72 months postoperatively. Functional outcomes were measured using the 1993 version of the Musculoskeletal Tumor Society (MSTS) scoring system with its six subheadings. Complications were defined as events that were substantial enough to result in surgery. Problems related to fibular donor site were also recorded.\r\n\r\nRESULTS\r\nIn patients who received reconstruction with irradiated autografts alone, graft loss occurred in five patients before union was achieved, and one patient died before 12 months; thus, these patients were excluded from analysis on union within 12 months. Among the remaining 31 patients, union was achieved within 12 months in 71% (22) of patients, delayed union in 16% (5) of patients, and nonunion in 13% (4) of patients. In the group in which vascularized fibula was used to augment the irradiated autograft, union occurred within 12 months in 9 of 13 patients, while delayed union and nonunion were observed in two patients each. There was no difference between the groups (p > 0.99). At 72 months, the cumulative incidence of graft loss was 32% (95% confidence interval [CI] 19.1% to 47.6%) in the irradiated autograft-alone group and 13% (95% CI 2.3% to 40.3%) in the fibula-augmented group. The cumulative incidence of death at 72 months was 25% (95% CI 13.9% to 40.3%) in the irradiated autograft-alone group and 20% (95% CI 5.0% to 48.6%) in the fibula-augmented group. Competing risk regression for graft loss, treating death as a competing event, showed no difference between the groups (subdistribution HR 0.42 [95% CI 0.10 to 1.84]; p = 0.25). The median (range) MSTS score in patients reconstructed with irradiated autograft alone was 27 (18 to 30), while the median (range) MSTS score in those reconstructed with irradiated autograft augmented with vascularized fibula was 24 (20 to 30), and there were no differences between the groups in terms of total MSTS scores or any of the MSTS subdomains. In patients reconstructed with irradiated autograft alone, a total of 28 complications were observed in 20 patients. For those patients, the median (range) time from surgery to complication was 15 months (2 to 72). In patients reconstructed with irradiated autograft augmented with vascularized fibula, a total of nine complications were observed in seven patients. For those patients, the median (range) time from surgery to occurrence of complication was 18 months (1 to 23). There was no difference between the two groups in terms of the proportion of patients who faced complication or the median time to occurrence of complications. A total of four patients experienced donor site-related problems, none of which resulted in further surgery.\r\n\r\nCONCLUSION\r\nDespite being applied in tougher lesions with less favorable bone quality, the addition of a vascularized fibula into extracorporeally irradiated autograft for reconstruction of intercalary resections yielded comparable outcomes in terms of bony union, graft survival, functional scores, and complications when compared with patients with more favorable host bone who received reconstruction with irradiated graft alone. Although our numbers were small, given the complexity and additional morbidity associated with vascularized fibular graft, its use might be reserved for selected patients in whom biological reconstruction is desired, but the host bone is deemed weakened and unlikely to be successful compared with those patients with more intact bone. Larger studies comparing this technique with other reconstruction options such as structural allografts, intercalary endoprostheses, or cement-rod constructs are needed to better define its role. We recommend reserving the use of vascularized fibula augmentation as a reinforcement strategy in reconstructions with irradiated autografts after intercalary resections of the femur and tibia, opting for it only when additional benefit is anticipated, given that it prolongs operative time, necessitates the involvement of a reconstructive surgery team, and introduces additional donor-site considerations.\r\n\r\nLEVEL OF EVIDENCE\r\nLevel III, therapeutic study.","PeriodicalId":10404,"journal":{"name":"Clinical Orthopaedics and Related Research®","volume":"40 1","pages":""},"PeriodicalIF":4.2000,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Clinical Orthopaedics and Related Research®","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1097/corr.0000000000003599","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ORTHOPEDICS","Score":null,"Total":0}
引用次数: 0

Abstract

BACKGROUND Extracorporeally irradiated autografting is a recognized technique in reconstruction after intercalary resections, but it has drawbacks such as nonunion and graft fracture. Because sterilized autografts lose some of their mechanical properties due to involvement of the cortex with tumor, the curettage, and the adverse effects of irradiation or other sterilization techniques, some have proposed adding vascularized fibula to augment the autograft. Because this potentially adds morbidity, we sought to address the value of adding vascular fibular grafts to reconstruction with irradiated autografts. QUESTIONS/PURPOSES Comparing patients who received an extracorporeally radiated autograft alone with those who received such a graft augmented by a free vascularized fibular autograft: (1) Was the proportion of patients who did not achieve union by 12 months higher in the group that received the augmented (vascularized) graft? (2) Did the augmented-graft group demonstrate greater survivorship free from graft loss at 72 months than did the group receiving an irradiated graft alone? (3) Were there between-group differences in functional results? (4) Were there between-group differences in complications, defined as those substantial enough to result in further surgery? METHODS In our single-center study, conducted in a tertiary academic referral center, we performed a retrospective chart audit of patients undergoing intercalary resections for primary sarcomas of the femur and tibia. Between January 2002 and April 2023, three surgeons (HK, BK, DS) treated 345 patients for bone sarcoma of the femur or tibia. Of those, we considered 25% (85) treated with intercalary resection for primary bone sarcomas as potentially eligible. A further 7% (23 of 345) of patients were excluded because their reconstruction was performed using a technique other than irradiated autografts. Another 2% (6) had died prior to the minimum follow-up period of 24 months, another 1% (3) did not finish the 24-month follow-up, and 1% (3) were lost to follow-up for > 5 years, leaving 14% (50 of 345) for analysis here. Among these, 26% (13 of 50) of patients underwent reconstruction involving an extracorporeally irradiated autograft and augmentation with a vascularized fibula autograft. In the remaining 37 patients, reconstruction was performed using extracorporeally irradiated bone alone. During this period, intercalary resection was typically indicated for patients with primary bone sarcomas located in the metaphyseal or diaphyseal regions without articular involvement, provided that they demonstrated a favorable response to neoadjuvant therapy. In this predominantly young patient cohort, extracorporeally irradiated autografts were our preferred reconstruction method after sarcoma resection. Isolated extracorporeally irradiated autografts were selected for patients with radiologic evidence of adequate bone quality and preserved cortical integrity. In patients who have a tumor with extensive cortical destruction-yet still considered suitable for reconstruction after irradiation-vascularized fibular grafts were added to the irradiated autografts. In the group reconstructed with irradiated autograft alone, 54% (20 of 37) of patients were male and 46% (17) were female, with a median (range) age of 15 years (4 to 60). The diagnoses included osteosarcoma in 51% (19 of 37) of patients and Ewing sarcoma in 32% (12). The tumor was located in the tibia in 59% (22) of patients and in the femur in 41% (15). In the group receiving irradiated autograft augmented with vascularized fibula, 6 of the 13 patients were male and 7 were female, with a median (range) age of 13 years (6 to 40). Diagnoses included osteosarcoma in eight of 13 patients, Ewing sarcoma in four, and malignant mesenchymal tumor in one patient. Tumor originated from the femur in 11 patients and from the tibia in two. The two groups were similar in terms of histopathologic diagnosis, age, gender, follow-up duration, and tumor location within bone while the proportion of tumors originating from the femur was higher in the group treated with vascularized fibula augmentation (85% versus 41%; p < 0.05). Fixation technique, the ratio of the resected bone length to the entire bone, was noted using the first postoperative radiograph. Bony union, defined as bony bridging in at least three cortices, was assessed using two-plane radiographs. Patients who achieved bony union within the first 12 months without undergoing any additional surgical intervention were classified as having union. Patients whose autograft incorporation exceeded 12 months but ultimately achieved union before 15 months without the need for additional intervention were classified as having delayed union. Nonunion was defined as when patients demonstrated incomplete integration at the 15-month follow-up or when patients needed additional intervention before healing. The survival of extracorporeally irradiated autografts, free from any degree of loss (partial or complete graft loss attributed to graft fracture resorption or graft removal after infection or recurrence), was assessed using competing risk analysis, with death as a competing event at 72 months postoperatively. Functional outcomes were measured using the 1993 version of the Musculoskeletal Tumor Society (MSTS) scoring system with its six subheadings. Complications were defined as events that were substantial enough to result in surgery. Problems related to fibular donor site were also recorded. RESULTS In patients who received reconstruction with irradiated autografts alone, graft loss occurred in five patients before union was achieved, and one patient died before 12 months; thus, these patients were excluded from analysis on union within 12 months. Among the remaining 31 patients, union was achieved within 12 months in 71% (22) of patients, delayed union in 16% (5) of patients, and nonunion in 13% (4) of patients. In the group in which vascularized fibula was used to augment the irradiated autograft, union occurred within 12 months in 9 of 13 patients, while delayed union and nonunion were observed in two patients each. There was no difference between the groups (p > 0.99). At 72 months, the cumulative incidence of graft loss was 32% (95% confidence interval [CI] 19.1% to 47.6%) in the irradiated autograft-alone group and 13% (95% CI 2.3% to 40.3%) in the fibula-augmented group. The cumulative incidence of death at 72 months was 25% (95% CI 13.9% to 40.3%) in the irradiated autograft-alone group and 20% (95% CI 5.0% to 48.6%) in the fibula-augmented group. Competing risk regression for graft loss, treating death as a competing event, showed no difference between the groups (subdistribution HR 0.42 [95% CI 0.10 to 1.84]; p = 0.25). The median (range) MSTS score in patients reconstructed with irradiated autograft alone was 27 (18 to 30), while the median (range) MSTS score in those reconstructed with irradiated autograft augmented with vascularized fibula was 24 (20 to 30), and there were no differences between the groups in terms of total MSTS scores or any of the MSTS subdomains. In patients reconstructed with irradiated autograft alone, a total of 28 complications were observed in 20 patients. For those patients, the median (range) time from surgery to complication was 15 months (2 to 72). In patients reconstructed with irradiated autograft augmented with vascularized fibula, a total of nine complications were observed in seven patients. For those patients, the median (range) time from surgery to occurrence of complication was 18 months (1 to 23). There was no difference between the two groups in terms of the proportion of patients who faced complication or the median time to occurrence of complications. A total of four patients experienced donor site-related problems, none of which resulted in further surgery. CONCLUSION Despite being applied in tougher lesions with less favorable bone quality, the addition of a vascularized fibula into extracorporeally irradiated autograft for reconstruction of intercalary resections yielded comparable outcomes in terms of bony union, graft survival, functional scores, and complications when compared with patients with more favorable host bone who received reconstruction with irradiated graft alone. Although our numbers were small, given the complexity and additional morbidity associated with vascularized fibular graft, its use might be reserved for selected patients in whom biological reconstruction is desired, but the host bone is deemed weakened and unlikely to be successful compared with those patients with more intact bone. Larger studies comparing this technique with other reconstruction options such as structural allografts, intercalary endoprostheses, or cement-rod constructs are needed to better define its role. We recommend reserving the use of vascularized fibula augmentation as a reinforcement strategy in reconstructions with irradiated autografts after intercalary resections of the femur and tibia, opting for it only when additional benefit is anticipated, given that it prolongs operative time, necessitates the involvement of a reconstructive surgery team, and introduces additional donor-site considerations. LEVEL OF EVIDENCE Level III, therapeutic study.
与没有骨丢失和骨增强的患者相比,在下肢骨间切除重建时,放射增强自体移植物与游离带血管的腓骨移植物在恶性肿瘤骨丢失患者中是否能达到愈合、功能和并发症发生率?
背景:自体放射植骨是骨间切除术后重建的一种公认的技术,但它存在骨不愈合和植骨骨折等缺点。由于肿瘤累及皮质、刮除以及辐照或其他灭菌技术的不良影响,灭菌的自体移植物失去了一些机械性能,一些人建议添加带血管的腓骨来增强自体移植物。由于这可能会增加发病率,我们试图解决增加血管腓骨移植物重建与辐照自体移植物的价值。问题/目的:比较单独接受体外放射自体移植物的患者与接受游离带血管的腓骨自体移植物增强的患者:(1)在接受增强(带血管)移植物的组中,12个月未愈合的患者比例是否更高?(2)增强移植物组是否比单独接受放射移植物组在72个月时表现出更大的无移植物损失的存活率?(3)各组功能结果是否有差异?(4)组间是否存在并发症的差异,即那些严重到足以导致进一步手术的并发症?方法:在我们的单中心研究中,在一个三级学术转诊中心进行,我们对股骨和胫骨原发性肉瘤行鞘间切除术的患者进行了回顾性图表审计。在2002年1月至2023年4月期间,三位外科医生(HK, BK, DS)治疗了345名股骨或胫骨骨肉瘤患者。其中,我们认为25%(85例)的原发性骨肉瘤行癌间切除术可能符合条件。另有7%(345例中的23例)的患者被排除在外,因为他们的重建是使用辐照自体移植物以外的技术进行的。另有2%(6)例患者在最短随访期24个月前死亡,1%(3)例患者未完成24个月的随访,1%(3)例患者失去了50 ~ 50年的随访,剩下14%(345例中的50例)在此进行分析。其中,26%(13 / 50)的患者接受了体外辐照自体移植物和带血管的自体腓骨移植物的重建。在其余37例患者中,仅使用体外照射骨进行重建。在此期间,对于位于干骺端或干骺端的原发性骨肉瘤患者,如果对新辅助治疗表现出良好的反应,则通常需要行骨间切除术。在这个以年轻患者为主的队列中,体外辐照自体移植物是我们首选的肉瘤切除术后重建方法。对于具有足够骨质量和保留皮质完整性的放射学证据的患者,选择分离的体外辐照自体移植物。对于有广泛皮质破坏的肿瘤患者,在照射后仍认为适合重建,血管化腓骨移植物被添加到照射后的自体移植物中。在单独放疗自体移植物重建组中,54%(20 / 37)为男性,46%(17)为女性,年龄中位数(范围)为15岁(4 - 60岁)。37例患者中有19例(51%)被诊断为骨肉瘤,12例(32%)被诊断为尤文氏肉瘤。肿瘤22例(59%)位于胫骨,15例(41%)位于股骨。在接受带血管腓骨的放射自体移植物增强组中,13例患者中6例为男性,7例为女性,中位(范围)年龄为13岁(6至40岁)。13例患者中有8例为骨肉瘤,4例为尤文氏肉瘤,1例为恶性间质瘤。肿瘤起源于股骨11例,胫骨2例。两组在组织病理学诊断、年龄、性别、随访时间和肿瘤在骨内的位置方面相似,而血管化腓骨增强组肿瘤起源于股骨的比例更高(85%对41%;P < 0.05)。固定技术,切除骨长度与整个骨的比例,通过术后第一次x线片记录。使用双平面x线片评估骨愈合,定义为至少三个皮质的骨桥接。在前12个月内实现骨愈合而未接受任何额外手术干预的患者被归类为骨愈合。自体移植物融合超过12个月,但最终在15个月前愈合而无需额外干预的患者被归类为延迟愈合。不愈合定义为患者在15个月的随访中表现出不完全融合或患者在愈合前需要额外干预。 采用竞争风险分析评估体外辐照自体移植物的生存,无任何程度的损失(由于移植物骨折吸收或感染或复发后移植物切除导致的部分或完全移植物损失),术后72个月死亡为竞争事件。功能结果使用1993年版的肌肉骨骼肿瘤协会(MSTS)评分系统进行测量,评分系统有六个小标题。并发症被定义为足以导致手术的事件。有关腓骨供体部位的问题也被记录。结果单独行放射自体移植物重建的患者中,5例患者在愈合前发生移植物丢失,1例患者在12个月内死亡;因此,这些患者被排除在12个月内的愈合分析之外。在其余31例患者中,71%(22例)的患者在12个月内愈合,16%(5例)的患者延迟愈合,13%(4例)的患者不愈合。在带血管腓骨增强放射自体移植物的组中,13例患者中有9例在12个月内愈合,而延迟愈合和不愈合各有2例。两组间差异无统计学意义(p < 0.99)。在72个月时,单独自体移植物照射组移植物损失的累积发生率为32%(95%可信区间[CI] 19.1%至47.6%),腓骨增强组为13%(95%可信区间[CI] 2.3%至40.3%)。单独自体骨移植组72个月的累计死亡率为25% (95% CI 13.9% ~ 40.3%),腓骨增强组为20% (95% CI 5.0% ~ 48.6%)。将死亡视为竞争事件的移植物丧失的竞争风险回归显示两组间无差异(亚分布HR 0.42 [95% CI 0.10至1.84];P = 0.25)。仅用辐照自体移植物重建的患者的中位(范围)MSTS评分为27分(18至30分),而用带血管腓骨的辐照自体移植物重建的中位(范围)MSTS评分为24分(20至30分),两组之间在总MSTS评分或任何MSTS亚域方面没有差异。在仅用辐照自体移植物重建的患者中,20例患者共观察到28例并发症。对于这些患者,从手术到并发症的中位(范围)时间为15个月(2至72)。在接受带血管腓骨的辐照自体移植物重建的患者中,7例患者共观察到9例并发症。这些患者从手术到发生并发症的中位时间(范围)为18个月(1 ~ 23个月)。两组在出现并发症的患者比例或并发症发生的中位时间方面没有差异。共有4名患者经历了与供体部位相关的问题,没有一例导致进一步的手术。结论:尽管将带血管的腓骨加入体外辐照自体移植物中用于骨质量较差的坚硬病变重建,但与仅用辐照移植物重建具有较好宿主骨的患者相比,在骨愈合、移植物存活、功能评分和并发症方面的结果相当。尽管我们的研究人数很少,但考虑到带血管腓骨移植物的复杂性和额外的发病率,它可能被保留给那些需要生物重建的患者,但与那些骨骼更完整的患者相比,宿主骨被认为是虚弱的,不太可能成功。需要更大规模的研究来比较该技术与其他重建选择,如结构异体移植物、骨间内假体或水泥棒结构,以更好地确定其作用。我们建议保留将带血管的腓骨增强作为一种加固策略,用于股骨和胫骨间质切除后辐照自体移植物重建,只有当预期有额外的益处时才选择它,因为它延长了手术时间,需要重建手术团队的参与,并引入了额外的供体部位考虑。证据等级:III级,治疗性研究。
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来源期刊
CiteScore
7.00
自引率
11.90%
发文量
722
审稿时长
2.5 months
期刊介绍: Clinical Orthopaedics and Related Research® is a leading peer-reviewed journal devoted to the dissemination of new and important orthopaedic knowledge. CORR® brings readers the latest clinical and basic research, along with columns, commentaries, and interviews with authors.
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