Department of Orthopaedic Surgery at the University of California, Los Angeles, Los Angeles, CA, USA.
Rothman Orthopaedic Institute at Thomas Jefferson University, Philadelphia, PA, USA.
Clin Orthop Relat Res. 2023 Nov 1;481(11):2236-2243. doi: 10.1097/CORR.0000000000002765. Epub 2023 Jul 14.
Proximal femur replacements (PFRs) are an effective surgical option to treat primary and metastatic tumors causing large bony defects in the proximal femur. Given the relative rarity of these indications, current studies on PFR for oncologic indications are generally limited by patient volume or relatively short-term follow-up. Because recent advances in systemic therapy have improved the prognosis of patients who undergo limb salvage surgery for musculoskeletal tumors, data on the long-term durability of endoprosthetic reconstructions have become increasingly important.
QUESTIONS/PURPOSES: (1) How does the long-term survival of cemented bipolar PFRs compare with patient survival in patients who underwent PFR for benign, aggressive, and metastatic tumors? (2) What are common reasons for revisions of primary PFRs? (3) Which factors are associated with survival of primary PFRs? (4) What is the survivorship free from conversion of bipolar PFRs to THA?
Between January 1, 1980, and December 31, 2020, we treated 812 patients with an endoprosthetic reconstruction for an oncologic indication. All patients who underwent a primary PFR for an oncologic indication were included in this study. The study cohort consisted of 122 patients receiving a primary PFR. Eighteen patients did not reach a censored endpoint such as death, revision, or amputation within 2 years. Thirty-three patients died within 2 years of their surgery. Of the 122 patients with primary PFRs, 39 did not reach a censored endpoint and have not been seen within the past 5 years. However, the mean follow-up time for these patients was longer than 10 years. The Social Security Death Index was queried to identify any patients who may have died but might not have been captured by our database To allow for adequate follow-up, endoprosthetic reconstructions performed after December 31, 2020 were excluded. The mean age at the time of the index surgery was 48 ± 22 years. The mean follow-up time of surviving patients was 7 ± 8 years. All PFRs were performed using a bipolar hemiarthroplasty with a cemented stem, and all implants were considered comparable. Demographic, oncologic, procedural, and outcome data including prosthesis survival, patient survival, complication rates, and rates of conversion to THA were analyzed. Patient, prosthesis, and limb salvage survival rates were generated, with implant revision as the endpoint and death as a competing risk. Statistical significance was defined as p < 0.05.
Generally, patients with benign or low-grade (Stage I) disease outlived their implants (100% patient survival through 30 years; p = 0.02), whereas the opposite was true in patients with high-grade, localized Stage II disease (64% patient survival at 5 years [95% CI 49% to 76%]; p = 0.001) or widespread Stage III metastatic disease (6.2% patient survival at 5 years [95% CI 0.5% to 24%]; p < 0.001). Primary PFR implant survival at 5, 10, 20, and 30 years was 97% (95% CI 90% to 99%), 81% (95% CI 67% to 90%), 69% (95% CI 46% to 84%), and 51% (95% CI 24% to 73%), respectively. Eight percent (10 of 122) of primary PFRs were revised for any reason. The most common causes of revision were aseptic loosening (3% [four of 122]), infection (3% [three of 122]), breakage of the implant (2% [two of 122]), and tumor progression (1% [one of 122]). Follow-up time was the only factor that was associated with revision of primary PFRs. Neither segment length nor stem length were associated with revision of primary. Six percent (seven of 122) of PFRs were converted to THA at a mean 15 ± 8 years from the index procedure. Survivorship free from conversion to THA (accounting for death as a competing risk) was 94% (95% CI 85% to 99%), 86% (95% CI 68% to 94%). and 77% (95% CI 51% to 91%) at 10, 20, and 30 years, respectively.
Cemented bipolar PFRs for an oncologic indication are a relatively durable reconstruction technique. Given the relative longevity and efficacy of PFRs demonstrated in our study, especially in patients with high-grade or metastatic disease where implant survival until all-cause revision was longer than patient survival, surgeons should continue to seriously consider PFRs in appropriate patients. The relative rarity of these reconstructions limits the number of patients in this study as well as in current research; thus, further multi-institutional collaborations are needed to provide the most accurate prognostic data for our patients.
Level III, therapeutic study.
股骨近端置换术（PFR）是治疗原发性和转移性肿瘤导致股骨近端大骨缺损的有效手术选择。鉴于这些适应症相对少见，目前关于 PFR 治疗肿瘤适应症的研究通常受到患者数量或相对短期随访的限制。由于系统治疗的最新进展改善了接受保肢手术治疗肌肉骨骼肿瘤的患者的预后，关于假体重建的长期耐用性的数据变得越来越重要。
问题/目的：(1) 与接受保肢手术治疗的良性、侵袭性和转移性肿瘤患者的患者生存率相比，骨水泥双极 PFR 的长期生存率如何？(2) 原发性 PFR 翻修的常见原因有哪些？(3) 哪些因素与原发性 PFR 的生存率相关？(4) 从双极 PFR 到 THR 转换的生存率是多少？
1980 年 1 月 1 日至 2020 年 12 月 31 日期间，我们为 812 名接受骨肿瘤治疗的患者进行了假体重建。本研究纳入了所有接受骨肿瘤保肢手术的患者。研究队列由 122 名接受原发性 PFR 的患者组成。18 名患者在 2 年内未达到死亡、翻修或截肢等删失终点。33 名患者在手术后 2 年内死亡。在 122 名接受原发性 PFR 的患者中，有 39 名未达到删失终点，且在过去 5 年内未接受过随访。然而，这些患者的平均随访时间超过了 10 年。我们查询了社会保障死亡指数以确定可能已经死亡但可能没有被我们的数据库捕获的患者。为了允许进行充分的随访，排除了 2020 年 12 月 31 日后进行的假体重建。指数手术时的平均年龄为 48 ± 22 岁。存活患者的平均随访时间为 7 ± 8 年。所有 PFR 均采用骨水泥半髋关节置换术联合骨水泥固定柄进行，所有植入物均被认为是可比的。分析了包括假体生存率、患者生存率、并发症发生率和 THR 转换率在内的人口统计学、肿瘤学、手术和结果数据。以假体翻修为终点，以死亡为竞争风险，生成患者、假体和肢体保肢生存率。统计学意义定义为 p < 0.05。
一般来说，患有良性或低级别（I 期）疾病的患者比他们的植入物寿命更长（30 年的患者生存率为 100%；p = 0.02），而患有高级别、局部 II 期疾病（5 年的患者生存率为 64%[95%CI 49%至 76%]；p = 0.001）或广泛 III 期转移性疾病（5 年的患者生存率为 6.2%[95%CI 0.5%至 24%]；p < 0.001）的患者则相反。5、10、20 和 30 年时，原发性 PFR 假体生存率分别为 97%（95%CI 90%至 99%）、81%（95%CI 67%至 90%）、69%（95%CI 46%至 84%）和 51%（95%CI 24%至 73%）。8%（122 例中有 10 例）的原发性 PFR 因任何原因而翻修。最常见的翻修原因是无菌性松动（3%[122 例中有 4 例]）、感染（3%[122 例中有 3 例]）、假体断裂（2%[122 例中有 2 例]）和肿瘤进展（1%[122 例中有 1 例]）。随访时间是唯一与原发性 PFR 翻修相关的因素。骨段长度和柄长度均与原发性 PFR 翻修无关。6%（122 例中有 7 例）的 PFR 在指数手术后 15 ± 8 年转换为 THR。考虑到死亡是竞争风险，从双极 PFR 到 THR 转换的无生存率为 94%（95%CI 85%至 99%）、86%（95%CI 68%至 94%）和 77%（95%CI 51%至 91%），分别为 10、20 和 30 年。
对于肿瘤适应症，骨水泥双极 PFR 是一种相对耐用的重建技术。鉴于我们的研究中 PFR 的相对长寿和有效性，特别是在高级别或转移性疾病患者中，假体生存直到所有原因翻修的时间长于患者生存时间，外科医生应继续认真考虑在适当的患者中使用 PFR。这些重建的相对罕见限制了本研究以及当前研究中的患者数量；因此，需要进一步的多机构合作，为我们的患者提供最准确的预后数据。
III 级，治疗性研究。
