OBJECTIVE: Proximal femur tumor resection often leads to hip joint instability and functional loss. Various methods have been clinically applied to repair hip joint soft tissue function, but deficiencies remain. This study aims to evaluate the advantages and disadvantages of the ligament advanced reinforcement system (LARS) tumor tube in assisting soft tissue function reconstruction in patients undergoing tumor type artificial hip replacement surgery.
METHODS: This study included 85 patients (41 males, 44 females) with proximal femoral tumors treated at the Xiangya Bone Tumor Treatment Center from January 2012 to January 2022, aged 10 to 79 (38.5±18.2) years. Among them, 13 cases had benign aggressive tumors, 45 had primary malignant bone tumors, and 27 had bone metastases. Clinical data, imaging data, and intraoperative photos were collected. Patients were followed up and postoperative functional evaluations were conducted using the Musculoskeletal Tumor Society (MSTS) scoring system and Harris hip joint scoring system to assess limb function and hip joint function.
RESULTS: Preoperative pathological fractures were present in 37 cases (43.5%), with a lesion length of (9.4±2.9) cm. Among non-metastatic tumor patients, 7 experienced postoperative recurrence, including 6 cases of osteosarcoma and 1 case of fibrosarcoma. Pulmonary metastases occurred in 9 osteosarcoma patients. Five patients required reoperation due to postoperative complications, including 3 cases of deep vein thrombosis, 1 case of giant cell granuloma, and 1 case of prosthesis infection. Postoperatively, 5 patients exhibited Trendelenburg gait, and 6 had leg length discrepancies. The postoperative MSTS score was 26.7±1.4, and the Harris score was 89.6±5.3.
CONCLUSIONS: The LARS tumor tube can effectively assist in reconstructing the soft tissue function of the hip joint and greatly reduce postoperative complications, making it an effective technical improvement in joint function reconstruction in tumor type artificial hip replacement surgery.
目的: 股骨近端肿瘤切除常导致髋关节不稳定和功能缺失，临床上已有多种方法用于修复髋关节软组织功能，但仍存在不足。本研究旨在评价韧带高级加固系统(ligament advanced reinforcement system，LARS)肿瘤管对辅助肿瘤型人工髋关节置换术患者软组织功能重建的优势与不足。方法: 2012年1月至2022年1月本研究共纳入湘雅骨肿瘤治疗中心的股骨近端肿瘤患者85例(男41例，女44例)，年龄10~79(38.5±18.2)岁，其中良性侵袭性肿瘤13例，原发恶性骨肿瘤45例，骨转移瘤27例。收集患者的临床资料、影像学资料和术中照片，对患者进行随访和术后功能评价。分别采用肌肉骨骼肿瘤学会(Musculoskeletal Tumor Society，MSTS)评分系统和Harris髋关节评分系统评价患者的肢体功能和髋关节功能。结果: 37例(43.5%)患者术前合并病理性骨折，病灶长度为(9.4±2.9) cm。非转移瘤患者术后复发7例，其中骨肉瘤6例，纤维肉瘤1例。9例骨肉瘤患者出现肺转移。5例因术后并发症再次手术，其中3例为深静脉血栓形成，1例为巨细胞肉芽肿，1例为假体周围感染。5例术后出现Trendelenburg步态。6例术后出现双下肢不等长。患者术后MSTS评分为26.7±1.4，Harris评分为89.6±5.3。结论: LARS肿瘤管可以有效辅助重建患者髋关节的软组织功能，并极大地减少了术后并发症的发生，是肿瘤型人工髋关节置换术中关节功能重建的有效技术改良。.

METHODS: A 71-year-old man with castration-resistant Stage IVB prostate cancer developed symptomatic oligometastatic disease in the lumbar spine and bilateral proximal femurs. He was treated with a single-position L2-L4 kyphoplasty with concomitant prone left-sided femoral prophylactic cephalomedullary nailing. Six months later when he again lost the ability to ambulate, he was treated with a single-position L4-L5 laminectomy for an epidural tumor with prone right-sided femoral prophylactic cephalomedullary nailing.
CONCLUSIONS: Single-position prone surgery of the spine and prone femoral nailing is feasible and improves on traditional multiposition approaches, eliminating the need to reposition or change tables during management.

OBJECTIVE: Parosteal Osteosarcoma is a well-differentiated, low-grade bone sarcoma. It most commonly occurs in the third decade of life, usually in the distal femur. This study aims to perform a literature review about the types of reconstructions reported and to analyze the results of an updated technique of resection using custom-made 3D-printed cutting guides.
METHODS: We perform a systematic literature review about parosteal osteosarcoma, evaluating treatments, margins, local recurrence, complications, and functional results when available. We also report a case treated in our Center with a revisited technique introducing custom-made 3D-printed cutting guides.
RESULTS: We analyzed 12 studies with a total of 151 patients. The distal femur was the most frequently reported site (81.5%). After distal femur resection, reconstruction was performed with graft in most cases (48%), followed by prosthetic reconstruction (40%). Margins were wide in 85.5% of cases. The total incidence of local recurrence was 11%. Functional results were excellent in all cases, with a mean MSTS score of 86%. In our case, with the help of the jigs, the surgical technique was relatively easy, graft fusion excellent and fast, margins wide, and functional results excellent.
CONCLUSIONS: In the literature, the most commonly used type of reconstruction after resection is biological with graft. Indeed, despite the increasing number of prosthetic reconstructions, the historical diaphysometaphyseal hemiresection and graft is still indicated in parosteal osteosarcoma of the distal femur. New technologies, such as the jigs we used, allow significant advantages during the procedure: reduce the resection and graft preparation time, allow a better match between components, and help to obtain safer margins, sparing as much bone as possible.

BACKGROUND: Total femur replacement (TFR) has become increasingly significant as a salvage procedure for both oncologic reconstruction and complex nononcologic conditions such as revision arthroplasty. Despite its effectiveness in limb salvage, TFR is associated with high complication and failure rates, which vary depending on the underlying indication.
METHODS: This systematic review and meta-analysis adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive search of MEDLINE, EMBASE, Web of Science, and Cumulative Index to Nursing and Allied Health Literature databases was conducted, focusing on studies that reported outcomes of TFR in oncologic and nononcologic cases. Primary outcomes included failure mode and rates according to the Henderson classification, functional outcomes scores, and mobility status. Data were analyzed using random-effects models and generalized linear mixed models.
RESULTS: A total of 35 studies involving 1,002 patients were included. The majority of TFRs were performed for oncologic reasons (63.7%). The mean Musculoskeletal Tumor Society (MSTS) score was 66%, with a limb salvage rate of 89%. The meta-analysis revealed a combined failure rate of 34%. For type 4 failures (infection), nononcologic patients exhibited a significantly higher rate at 18% (95% confidence interval [CI], 12%-26%, I2 = 46%, p < 0.01) compared with 8% in oncologic patients (95% CI, 6%-12%, I2 = 0%). Regarding combined types 1 to 4 failures, oncologic patients had a rate of 20% (95% CI, 25%-52%, I2 = 60%), whereas nononcologic patients faced a higher rate of 37% (95% CI, 12%-26%, I2 = 63%) (p < 0.05), indicating a significant difference. There were no significant differences in the MSTS score. In addition, there were no notable differences when comparing failure modes 1, 2, and 3 independently. Mobility analysis showed that approximately 70% of patients required walking aids after surgery.
CONCLUSIONS: TFR offers a valuable limb salvage option in both oncologic and nononcologic scenarios, despite its high failure rates. Although functional outcomes were similar between groups, the higher failure rate in nononcologic cases and the poor overall quality of evidence warrant further comprehensive assessments into predictors of outcomes to optimize results.
METHODS: Level III. See Instructions for Authors for a complete description of levels of evidence.

The distal femur is one of the most common sites for primary bone tumors. As the tumor progresses and bone destruction worsens, it can severely affect knee function and even pose a threat to life. In cases where only one condyle is affected and requires resection, preserving the healthy contralateral condyle can substantially enhance the biomechanics of the knee. Furthermore, preserving bone stock may enable future salvage procedures in the event of initial surgery failure, be it from fractures or osteoarthritis. Distal femoral unicondyle resection can offer better functional outcomes in select cases. However, it is essential to prioritize oncological safety with adequate margins over short-term knee function. Currently, the primary methods for reconstruction after the excision of a unicondylar tumor include allograft transplantation (bi- or uni-condylar) and prosthetic or allograft-prosthesis composite replacement (APC). However, there is currently some controversy regarding the optimal surgical reconstruction method, and a consensus within the academic community has yet to be reached. Moreover, due to the rarity of bone tumors, extensive clinical data from a single center is limited. Current studies are mainly retrospective and single-center, lacking sufficient cases and follow-up duration. This article reviews surgical reconstruction after solitary condylar excision in distal femoral tumors. It summarizes, compares, and analyzes mainstream reconstruction methods, exploring their technical details and clinical outcomes to highlight their potential in bone oncology.

暂无摘要。

BACKGROUND: Surgical treatment for hinge failure in mega-prosthesis continues to be a challenge. This study introduces a new method for treating hinge failure by using a unilateral prosthesis and hinge revision.
METHODS: We here present two patients who underwent mega-prosthesis reconstruction after resection of osteosarcoma in the distal femur. To address the issue of knee hyperextension after mega-prosthesis reconstruction, one patient underwent three revision surgeries, two surgeries were performed using the original hinge, and one surgery involved a newly designed hinge. To resolve the problem of dislocation, one patient underwent three revisions, with the first two revisions not involving hinge replacement and the third revision involving a newly designed hinge. Two replacements of unilateral prosthesis and hinge renovations were successful.
CONCLUSIONS: Unilateral prosthesis and newly designed hinge device revision are effective in treating the failure of old-fashioned mega-prosthesis hinges.

METHODS: This is a first report describing preservation of the femoral head by transcervical resection of proximal femoral Ewing sarcoma in 2 pediatric patients. A unique Capanna reconstruction supported joint salvage. At 1 year, Pediatric Outcomes Data Collection Instrument and Pediatric Toronto Extremity Salvage Score outcomes were excellent. Surveillance magnetic resonance imaging was without evidence of recurrence or impaired perfusion to the femoral head.
CONCLUSIONS: We demonstrate the feasibility of hip joint preservation and maintenance of femoral head viability after transcervical resection of pediatric proximal femur bone sarcomas while preserving the medial circumflex femoral artery. This technique may be a preferred option over joint sacrifice and endoprosthetic replacement in young patients when tumor margins permit.

BACKGROUND: Metastatic femoral tumors may lead to pathological fractures during daily activities. A CT-based finite element analysis of a patient\'s femurs was shown to assist orthopedic surgeons in making informed decisions about the risk of fracture and the need for a prophylactic fixation. Improving the accuracy of such analyses ruqires an automatic and accurate segmentation of the tumors and their automatic inclusion in the finite element model. We present herein a deep learning algorithm (nnU-Net) to automatically segment lytic tumors within the femur.
METHODS: A dataset consisting of fifty CT scans of patients with manually annotated femoral tumors was created. Forty of them, chosen randomly, were used for training the nnU-Net, while the remaining ten CT scans were used for testing. The deep learning model\'s performance was compared to two experienced radiologists.
RESULTS: The proposed algorithm outperformed the current state-of-the-art solutions, achieving dice similarity scores of 0.67 and 0.68 on the test data when compared to two experienced radiologists, while the dice similarity score for inter-individual variability between the radiologists was 0.73.
CONCLUSIONS: The automatic algorithm may segment lytic femoral tumors in CT scans as accurately as experienced radiologists with similar dice similarity scores. The influence of the realistic tumors inclusion in an autonomous finite element algorithm is presented in (Rachmil et al., \"The Influence of Femoral Lytic Tumors Segmentation on Autonomous Finite Element Analyses\", Clinical Biomechanics, 112, paper 106192, (2024)).

OBJECTIVE: Oncological distal femur resections can leave a proximal femur too short to host a stem. Reconstructive techniques are then challenging. The purpose of the study is to compare implant survival, complication rate and MSTS of two different options.
METHODS: We retrospectively divided 33 patients with primary bone tumours of distal femur in Group 1 (16 patients reconstructed with knee megaprosthesis with proximal bone augmentation, APC) and Group 2 (17 patients reconstructed with total femur prosthesis, TFP). Less than 12 cm of remaining proximal femur were planned for all resections.
RESULTS: MSTS score at 2 years is 25 ± 5 for Group 1 and 19 ± 7 for Group 2 (confidence interval [C.I.] 95%, p = 0.02). At 5 years it is 27 ± 2 for Group 1 and 22 ± 6 for Group 2 (C.I. 95%, p = 0.047). Failure and complication rates are lower for Group 1, but no statistical significance was reached. In APC reconstruction, union at the host-allograft junction was achieved in 16 out of 16 patients using the telescopic bone augmentation technique.
CONCLUSIONS: APC provides higher functional results compared to TFP after extended distal femur resection. In APC reconstruction, telescopic augmentation is excellent for achieving union at the host-allograft junction.