Outcomes of ilium and iliosacral Ewing's sarcoma resection reconstructed with tibial strut allograft.

Aims: Ilium is the most common site of pelvic Ewing's sarcoma (ES). Resection of the ilium and iliosacral joint causes pelvic disruption. However, the outcomes of resection and reconstruction are not well described. In this study, we report patients' outcomes after resection of the ilium and iliosacral ES and reconstruction with a tibial strut allograft. Methods: Medical files of 43 patients with ilium and iliosacral ES who underwent surgical resection and reconstruction with a tibial strut allograft between January 2010 and October 2021 were reviewed. The lesions were classified into four resection zones: I1, I2, I3, and I4, based on the extent of resection. Functional outcomes, oncological outcomes, and surgical complications for each resection zone were of interest. Functional outcomes were assessed using a Musculoskeletal Tumor Society (MSTS) score and Toronto Extremity Salvage Score (TESS). Results: The mean age of the patients was 17 years (SD 9.1). At a mean follow-up of 70.8 months (SD 50), the mean functional outcomes were 24.2 points (SD 6.3) for MSTS and 81 points (SD 11) for TESS. The mean MSTS and TESS scores were associated with the iliac resection zone (< 0.001). Nine patients (20.9%) had local recurrence. The recurrence was not associated with the zone of iliac resection (p = 0.324). The two-year disease-free survival of the patients was 69.4%. The mean time to graft union was longer in patients with the I4 resection zone (p < 0.001). The complication rate was 34.9%, and nerve palsy (11.6%) was the most common. The rate of surgical complications was not associated with the resection zone. Conclusion: Reconstruction using tibial strut allograft is an efficient procedure after the resection of the ilium and iliosacral ES. Functional outcomes and complications of iliac ES depend on the resection zone, and inferior outcomes could be generally expected when more segments of the pelvic ring are resected, even if it is reconstructed.

Outcomes of Megaprosthesis Reconstruction for the Salvage of Failed Osteoarticular Allograft Around the Knee implanted before Skeletal Maturity in Primary Bone Sarcoma: A Case-Series.

Objectives: Functional expectations following the salvage of a failed osteoarticular allograft are poorly described. In this study, we aim to evaluate functional outcomes, implant survival, and complications of the megaprosthesis in salvaging a failed osteoarticular allograft around the knee. Methods: We retrospectively reviewed the medical profiles of 21 skeletally mature patients who underwent megaprosthesis reconstruction to salvage a failed osteoarticular allograft around the knee implanted before skeletal maturity. The location of reconstruction was the proximal tibia in 13 patients and the distal femur in eight patients. Knee function was evaluated by the Musculoskeletal Tumor Society (MSTS) score and the Toronto Extremity Salvage Score (TESS). Results: The mean age of patients was 16±1.7 years. The mean interval between the primary (allograft) and secondary (megaprosthesis) reconstructions was 59.4±23.6 months. At an average follow-up of 51.2 months, the mean knee range of motion was 101.2±15.6°. The mean MSTS score and TESS were 83.6±7 and 86.6±7.9, respectively. The mean limb length discrepancy was 2.5±1 cm before and 0.36±0.74 cm after the operation (P<0.001). Six postoperative complications (28.6%) occurred in this series, including one wound dehiscence, one periprosthetic fracture, two acute infections, one aseptic loosening, and one delayed periprosthetic infection. Only the last two complications required revision. Accordingly, the two- and five-year implant survivals were 95.7% and 90%, respectively. Conclusion: Megaprosthesis is a viable option for salvaging failed osteoarticular allografts around the knee. It also provides the opportunity to correct the limb length discrepancy.

Does the intercondylar approach provide a better outcome for chondroblastoma of the distal femur in skeletally immature patients?

Aims: The epiphyseal approach to a chondroblastoma of the intercondylar notch of a child's distal femur does not provide adequate exposure, thereby necessitating the removal of a substantial amount of unaffected bone to expose the lesion. In this study, we compared the functional outcomes, local recurrence, and surgical complications of treating a chondroblastoma of the distal femoral epiphysis by either an intercondylar or an epiphyseal approach. Methods: A total of 30 children with a chondroblastoma of the distal femur who had been treated by intraregional curettage and bone grafting were retrospectively reviewed. An intercondylar approach was used in 16 patients (group A) and an epiphyseal approach in 14 (group B). Limb function was assessed using the Musculoskeletal Tumor Society (MSTS) scoring system and Sailhan's functional criteria. Results: At final follow-up, the mean MSTS score was 29.1 (SD 0.9) in group A and 26.7 (SD 1.5) in group B (p = 0.006). According to Sailhan's criteria, the knee function was good and fair in 14 (87.5%) and two (12.5%) patients of group A, and eight (57.1%) and six (42.9%) patients of group B, respectively (p = 0.062). The lesion had recurred in one patient (6.2%) in group A and four patients (28.6%) in group B. Limb shortening > 1 cm was recorded in one patient (6.2%) from group A and six patients (42.8%) from group B. Joint degeneration was noted in one patient from group A and three patients from group B. Conclusion: An intercondylar approach to a chondroblastoma of the middle two-quarters of the distal femoral epiphysis results in better outcomes than a medial or lateral epiphyseal approach: specifically, better limb function, a lower rate of recurrence, and a lower rate of physeal damage and joint degeneration.

The Effect of Multidimensional Spiritual Psychotherapy on the Quality of Life of Bone Cancer Survivors with a History of Lower Extremity Amputation.

INTRODUCTION: This study aimed to investigate the effect of multidimensional spiritual psychotherapy on anxiety, depression, and attitude towards self and god in bone cancer patients after amputation. METHOD: Forty one cancer patients with a history of Below-The-Knee amputation were recruited in this quasi-experimental study. The design included pre-and post-tests in experimental and control  groups. The experimental group received 15 sessions of multidimensional spiritual psychotherapy. Cattell Anxiety Inventory (CAI), Beck Anxiety Inventory (BAI), Beck's Depression Inventory (BDI), Religious Adherence Questionnaire (RAQ), and Self-concept-God concept questionnaire were administered for data collection. RESULTS: There was a significant difference between the control and experimental groups in terms of anxiety (P=0.0001), Depression (P=0.0001), God-image (P=0.035, F(1,38)=4.79), God-concept (P=0.006, F(1,38)=8.58), self-image (P=0.0001, F(1,38)=98.62), and self-concept (P=0.0001, F(1,38)=120.56), psychological evolution (P=0.0001, F(1,38)=19.36), and religious adherence (P=0.0001, F(1,38)=84.21). CONCLUSION: The results of the study indicated that the emphasis on spirituality and the implementation of spiritual care could improve the cancer amputated patients' well-being.

The clinical significance of CD44v6 in malignant and benign primary bone tumors.

BACKGROUND: The objective of this study was to assess the expression profile of CD44v6, a potential cancer stem cell marker, and its diagnostic and predictive significance in three distinct types of primary bone tumors. METHODS: In this study, we utilized real-time qRT-PCR and immunohistochemistry to examine the gene and protein levels of CD44v6 in a total of 138 fresh bone tissues. This included 69 tumor tissues comprising osteosarcoma (N = 23), chondrosarcoma (N = 23), and GCT (N = 23), as well as 69 corresponding non-cancerous tumor margins. Furthermore, we investigated the circulating level of CD44v6 by isolating peripheral blood mononuclear cells from 92 blood samples. Among these, 69 samples were obtained from patients diagnosed with primary bone tumors, while the remaining 23 samples were from healthy donors. The primary objectives of our investigation were to assess the correlation between CD44v6 expression levels and clinic-pathological features of the patients, as well as to evaluate the diagnostic and predictive values of CD44v6 in this context. RESULTS: In patients with osteosarcoma and chondrosarcoma tumors, both the gene and protein expression of CD44v6 were found to be significantly higher compared to the GCT group. Furthermore, the circulating level of CD44v6 was notably elevated in patients diagnosed with osteosarcoma and chondrosarcoma in comparison to the GCT group and patients with malignant tumor characteristics. Additionally, we observed a strong correlation between the gene and protein levels of CD44v6 and important tumor indicators such as tumor grade, metastasis, recurrence, and size at the tumor site. CD44v6 shows potential in differentiating patients with bone tumors from both control groups and tumor groups with severe and invasive characteristics from those with non-severe features. Importantly, the expression level of CD44v6 also demonstrated predictive value for determining tumor grade and the likelihood of recurrence. CONCLUSION: CD44v6 is likely to play a role in the development of primary bone tumors and has the potential to serve as a diagnostic biomarker for bone cancer. However, to obtain more accurate and conclusive findings, further mechanistic investigations involving larger population samples are necessary.

Establishment of Iran Musculoskeletal Tumor Registry: A Study Protocol and Lessons Learned from Implementation and the Pilot Phase.

Background: The number of available musculoskeletal tumor registries is relatively small. We developed a registry system focused on the clinical aspects of musculoskeletal tumors to improve quality of care indexes through the development of updated national protocols. In this study, we describe our protocol, challenges, and the data collected during the implementation of the registry system in a single-specialty orthopedic center in Iran. Methods: Three main malignant bone tumors, including osteosarcoma, Ewing sarcoma, and chondrosarcoma, were included in the registry. After establishing a steering committee, we defined the minimum data set based on a literature review and suggestions from an expert panel. Accordingly, the data collection forms and the web-based software were developed. The collected information was categorized into 9 classes, including demographics, socioeconomic data, signs and symptoms, past medical history, family history, laboratory tests, tumor characteristics, primary treatment, and follow-up. Data collection was performed both retrospectively and prospectively. Results: Until September 21, 2022, a total of 71 patients were registered (21 patients prospectively and 50 patients retrospectively) and consisted of 36 (50.7%) cases of osteosarcoma, 13 (18.3%) cases of Ewing sarcoma, and 22 (31%) cases of chondrosarcoma. The implementation of the registry demonstrated promising data regarding the tumor characteristics, delay patterns, and socioeconomic status of the patients. Conclusion: The main lessons learned were to develop a monitoring system to make sure that the new staff is adequately trained for the registration process as well as avoid the inclusion of time-consuming useless data in the minimum data set.

Total Synovectomy and Bone Grafting/Cementation after Curettage of the Bone Lesion in Diffuse Type of Tenosynovial Giant Cell Tumor : A Retrospective Cohort Study.

Objectives: Although the diffuse type of tenosynovial giant cell tumor (D-TGCT) is rare, bone involvement is common in such lesions. However, the optimal management of bone lesions in D-TGCT is not well-described. In this study, we reported the outcomes of total synovectomy, curettage, and bone grafting/cementation in the treatment of D-TGCT with subchondral bone involvement. We also described the prevalence, demographic, and characteristic features of the lesions. Methods: In a retrospective study, we included 13 patients with D-TGCT of large joints and associated subchondral cyst/cyst-like bone lesions of ≥ 5 mm that were managed with total synovectomy and curettage. Cavities with a bone defect of ≤ 30 mm (n=12) were filled with bone grafts. Cavities of > 30 mm (n=1) were augmented with bone cement. The limb function was evaluated by the Musculoskeletal Tumor Society (MSTS) score. Results: The study population consisted of 6 (46.1%) males and 7 (53.9%) females with a mean age of 30 ± 7.9 years. The most frequent sites of involvement were the knees and ankle joints (n=5 each, 38.5%). The mean follow-up of the patients was 69.2 ± 32.9 months. The mean MSTS score of the patients was obtained at 98.2 ± 3.2 (range 90-100). The D-TGCT recurred in two patients, both of which were in the synovium. Postoperative complications were three cases of transient pain and one case of knee joint stiffness. While no patient had an osteoarthritic change in preoperative radiographs, two patients had osteoarthritic change (grade II) in the last follow-up, one in the knee and one in the hip. Conclusion: Curettage and filling the defect with bone graft or cement are adequate treatments for managing bone lesions in D-TGCT.

Outcomes of proximal humeral reconstruction with cemented osteoarticular allograft in pediatric patients: a retrospective cohort study.

BACKGROUND: There is no agreement on the best choice of proximal humeral reconstruction following tumor resection in pediatric patients. We reviewed the functional outcomes, oncologic outcomes, and surgical complications in pediatric patients after proximal humeral reconstruction with cemented osteoarticular allograft. METHODS: Eighteen patients aged 8-13 years who underwent proximal humeral osteoarticular allograft reconstruction following resection of primary bone sarcoma were included. The mean follow-up period was 88 ± 31.7 months. At the last follow-up assessment, limb function was evaluated based on shoulder range of motion, Musculoskeletal Tumor Society score, and Toronto Extremity Salvage Score. Tumor recurrence and postoperative complications were extracted from the patients' medical records. RESULTS: Mean active forward flexion of the shoulder was 38° ± 18°. Mean active abduction was 48° ± 18°. Mean active external rotation was 23° ± 9°. The mean Musculoskeletal Tumor Society score was 73.4% ± 11.2%. The mean Toronto Extremity Salvage Score was 75.6% ± 12.9%. Local recurrence occurred in 1 patient. Metastasis developed after the operation in 2 additional patients. We recorded 6 postoperative complications in this series, including 1 superficial infection, 1 late-onset deep infection, 1 allograft fracture, 2 cases of nonunion, and 2 cases of shoulder instability. Two complications required allograft removal. CONCLUSION: In pediatric patients, reconstruction of the proximal humerus with cemented osteoarticular allograft results in acceptable oncologic and functional outcomes while the postoperative complication rate seems to be lower than that of other available techniques.

Scapular Osteosarcoma Treated by Scapulectomy with or Without Scapular Allograft: A Retrospective Case Series.

Background: Osteosarcoma of the scapula is extremely rare. Hence, there is no consensus regarding its optimal management. In this study, we report the demographics, characteristic features, and outcomes of scapulectomy with or without scapular allograft reconstruction in a series of patients with primary scapular osteosarcoma. Materials and Methods: Twelve patients with primary scapular osteosarcoma who were treated by scapulectomy with or without scapular allograft reconstruction (five and seven patients, respectively) were included. The allograft was fixed in place using a dacron tape without a plate or screw. The function of the shoulder was evaluated using the Musculoskeletal Tumor Society (MSTS) score for the upper extremity and Toronto Extremity Salvage Score (TESS). Results: The study population included seven (58.3%) males and five (41.7%) females with a mean age of 30 ± 8.2 years. The histologic type of the tumor was osteoblastic in the majority of patients (n = 8, 66.7%). At an average follow-up of 6.5 ± 2.3 years, only one local recurrence (8.3%) occurred in our patients that coincided with lung metastasis. The mean MSTS score was 78.7 ± 3.8% and 66.2 ± 4% in patients with and without scapular allograft, respectively (P = 0.006). The mean TESS was 78.6 ± 5.6 and 68.4 ± 2.4 in patients with and without scapular allograft, respectively (P = 0.005). The overall 5-year survival of the patients was 85.7%. Conclusion: Osteosarcoma of scapula more frequently occurs in the fourth decade of life, mainly presented with a sclerotic radiologic appearance. Patients with scapular allograft impaction after scapulectomy have better functional outcomes compared to those without boney reconstruction.

Intraosseous Ganglion Cyst of the Talus Treated With Curettage and Bone Grafting Through a Medial Malleolus Osteotomy.

BACKGROUND: Intraosseous ganglion cyst (IGC) of the talus is a rare entity. There is no consensus regarding the best surgical approach to the talus. In this study, we evaluated the outcomes of curettage and bone grafting of the talus IGC via medial malleolus osteotomy. METHODS: Seventeen patients with talus IGC who were treated between 2002 and 2020 using curettage and bone grafting through a medial malleolus osteotomy were included. The outcome measures were ankle range of motion (ROM), pain, and function. The ankle pain was evaluated by the visual analog scale (VAS). The ankle function was evaluated by the Toronto extremity salvage score (TESS) and Musculoskeletal Tumor Society (MSTS) score. RESULTS: The study population included 10 men and 7 women with a mean age of 34.9 ± 18.8 years and a mean follow-up of 5.4 ± 3 years. The mean size of the lesion was 2.6 ± 0.8 cm. Postoperatively, mean ankle dorsiflexion and plantar flexion were 19.4 ± 5.8 degrees and 36.7 ± 5.3 degrees, respectively. The mean VAS was 0.9 ± 1.1. The mean MSTS score and TESS were 96.2 ± 3.5 and 94.5 ± 4.1, respectively. Two patients developed ankle osteoarthritis after 3 years (1 stage I and 1 stage II). One of these patients (stage II) also had recurrence after 6 months (recurrence rate: 6.7%). CONCLUSION: Talus IGC could be adequately managed with curettage and bone grafting through a medial malleolus osteotomy. Even so, mild pain and reduced ankle ROM remain in some patients. LEVEL OF EVIDENCE: Level IV, retrospective cohort study.

A comparison of osteoarticular allografts and allograft-prosthesis composites for reconstruction of the distal femur after resection of a bone tumour in childhood : a retrospective study.

AIMS: Osteoarticular reconstruction of the distal femur in childhood has the advantage of preserving the tibial physis. However, due to the small size of the distal femur, matching the host bone with an osteoarticular allograft is challenging. In this study, we compared the outcomes and complications of a resurfaced allograft-prosthesis composite (rAPC) with those of an osteoarticular allograft to reconstruct the distal femur in children. METHODS: A retrospective analysis of 33 skeletally immature children with a malignant tumour of the distal femur, who underwent resection and reconstruction with a rAPC (n = 15) or osteoarticular allograft (n = 18), was conducted. The median age of the patients was ten years (interquartile range (IQR) 9 to 11) in the osteoarticular allograft group and nine years (IQR 8 to 10) in the rAPC group (p = 0.781). The median follow-up of the patients was seven years (IQR 4 to 8) in the osteoarticular allograft group and six years (IQR 3 to 7) in the rAPC group (p = 0.483). Limb function was evaluated using the Musculoskeletal Tumor Society (MSTS) score. RESULTS: At final follow-up, the knee was unstable in 9/18 patients (50%) in the osteoarticular allograft group and 2/15 patients (13%) in the rAPC group (p = 0.026). The median range of motion (ROM) of the knee was 117° (IQR 115° to 120°) in the osteoarticular allograft group and 100° (IQR 95° to 105°) in the rAPC group (p < 0.001). The median MSTS score was 25 (IQR 23 to 26) in the osteoarticular allograft group and 28 (IQR 26 to 29) in the rAPC group (p = 0.007). Osteoarthritic change was detected in 11/18 patients (61%) in the osteoarticular allograft group and in 4/15 (26%) patients in the rAPC group (p = 0.048). CONCLUSION: In our series, a resurfaced allograft-prosthesis composite provided better knee stability and function, with a lower rate of osteoarthritis; an osteoarticular allograft was associated with better knee ROM.Cite this article: Bone Joint J 2022;104-B(10):1174-1179.

Effect of an Endoprosthetic Reconstruction Tube and Medial Gastrocnemius Flap on Extensor Mechanism Function After Oncologic Prosthesis Reconstruction of the Proximal Tibia.

BACKGROUND: Extensor mechanism reconstruction after the proximal tibial resection and implantation of a megaprosthesis is challenging. In this study, we evaluated the effectiveness of the Trevira tube and medial gastrocnemius flap in restoring extensor mechanism following the resection of proximal tibial tumor and implantation of megaprosthesis. METHODS: Forty patients who underwent endoprosthetic implantation following the resection of proximal tibial tumor and patellar tendon reconstruction with the Trevira tube and medial gastrocnemius flap were included. The outcome measures were knee range of motion, extensor mechanism function, patellar position, and limb function subjectively evaluated through Toronto Extremity Salvage Score and objectively through Musculoskeletal Tumor Society score. The mean follow-up of the patients was 6.1 years. RESULTS: The patellar position was normal in 28 (70%) patients, patella baja in 3 (7.5%) patients, and patella alta in 9 (22.5%) patients. The mean active knee range of motion was 98.9 ± 17° (range: 85°-125°). Extension lag was present in 7 (17.5%) patients (range: 5°-20°). The mean Toronto Extremity Salvage Score of patients was 92.1 ± 6.9% (range: 85-100). The mean Musculoskeletal Tumor Society score of the patients was 87.7 ± 13 (range: 73.3-100). Postoperative complications included aseptic wound dehiscence (2 patients), aseptic loosening of the tibial component (1 patient), periprosthetic fracture in the femur (2 patients), and wound infection (1 patient). CONCLUSION: Trevira tube combined with gastrocnemius flap augmentation is a suitable procedure for restoring extensor mechanism after proximal tibial resection and megaprosthesis implantation.

Expression pattern and clinical significance of ß-catenin gene and protein in patients with primary malignant and benign bone tumors.

This study is aimed to unravel the status of local and circulating ß-catenin in different primary bone tumors and its relevance to tumor types, severity, and chemotherapy. The ß-catenin mRNA expression level and the expression of the protein (intensity level) were evaluated in tumor tissue and peripheral blood mononuclear cells of 150 patients with different types of primary bone tumors (78 malignant and 72 benign tumors) using Real-Time PCR and immunohistochemistry. The ß-catenin mRNA expression level and the expression of the protein were increased in bone tumors which was positively correlated with the tumor malignancy. Amongst osteosarcoma, Ewing's Sarcoma, chondrosarcoma, osteochondroma, Giant Cell Tumor, and exostosis tumors, the osteosarcoma, and Giant Cell Tumor groups showed the highest level of ß-catenin expression. The ß-catenin expression in malignant bone tumors was significantly correlated with tumor grade, size, metastasis, tumor recurrent, and the level of response to chemotherapy. A similar pattern of ß-catenin gene expression and its association with tumor characteristics was detected in the patient's peripheral blood cells. The simultaneous increase in the expression of the ß-catenin gene and protein in tumor tissue and in circulating blood cells and its relationship with tumor severity indicates the possible promoting role of ß-catenin in primary bone tumor pathogenesis.

Non-spinal Hydatid Disease of Bone: A Series of Nine Cases.

Background: Extra-spinal osseous hydatid disease is reported in a small number of case series. In the present study, we report our experience with extra-spinal hydatid disease of the bone in a series of nine patients. Methods: In this retrospective study, the patients who were diagnosed with an extra-spinal osseous hydatid disease were included. All patients were treated surgically. Preoperative anthelmintic drugs were employed for the cysts that were diagnosed before the operation. Postoperative chemotherapy was performed for all patients. Results: The study population included nine patients, including seven males and two females, with a mean age of 45.2±7.9 years and an average follow-up of 4.1±2.7 years. Non-specific pain was the most common symptom at presentation. Pelvic bones were the most frequent site of involvement. Serologic tests were false negative in seven patients. The disease was diagnosed preoperatively in five patients, and all of them were located in flat bones. The cysts were treated by radical excision in four patients, extended curettage in four patients, and amputation in one patient. The recurrence of the lesion was recorded in two patients who were treated by intralesional curettage. One case of suppuration was the only postoperative complication of this series. Conclusion: Osseous hydatid disease is a serious disease with challenging diagnosis, difficult treatment, and significant morbidity. Preoperative diagnosis is generally easier in flat bones. Radical resection is the optimal treatment of this disease, while non-radical resection is associated with a higher risk of recurrence.

How the Choice of Osteosynthesis Affects the Complication Rate of Intercalary Allograft Reconstruction? A Systematic Review and Meta-analysis.

Background: There is no clear consensus on the optimal type of fixation in intercalary allograft reconstruction. In this study, we aimed to compare the rate of most common complications following the plate and nail fixation of the intercalary allograft. Materials and Methods: We searched PubMed, EMBASE, Web of Science, Scopus, and Cochrane Library. Studies in which the complication rate of the single bridging plate and intramedullary nail fixation was extractable were included. Studies that used extra procedures such as cementation and fibular vascular graft augmentation were excluded. The primary outcome was the fixation-specific rate of nonunion. Secondary outcomes were the fixation-specific rate of fracture, infection, and local recurrence. Results: In total, 13 studies with 431 reconstructions (352 reconstructions in the plate group and 79 reconstructions in the intramedullary nailing group) were included in this study. In the plate fixation, the rate of nonunion, fracture, infection and local recurrence was 12%, 11%, 11%, and 3%, respectively. In the intramedullary nail fixation, the rate of nonunion, fracture, infection, and local recurrence was 37%, 5%, 4%, and 0%, respectively. The rate of nonunion was significantly higher in the intramedullary nail group (OR = 6.34; 95% CI 2.98-13.49, P < 0.001). The rate of fracture, infection, and local recurrence was not significantly different between the two fixation methods. Conclusions: Intramedullary nail is associated with a significantly higher rate of nonunion. Since the rate of other complications was not significantly different between the two osteosynthesis types, plate fixation could be considered as a better type of fixation. Supplementary Information: The online version contains supplementary material available at 10.1007/s43465-021-00563-7.

Fibular strut allograft or bone cement for reconstruction after curettage of a giant cell tumour of the proximal femur : a retrospective cohort study.

AIMS: Giant cell tumours (GCTs) of the proximal femur are rare, and there is no consensus about the best method of filling the defect left by curettage. In this study, we compared the outcome of using a fibular strut allograft and bone cement to reconstruct the bone defect after extended curettage of a GCT of the proximal femur. METHODS: In a retrospective study, we reviewed 26 patients with a GCT of the proximal femur in whom the bone defect had been filled with either a fibular strut allograft (n = 12) or bone cement (n = 14). Their demographic details and oncological and nononcological complications were retrieved from their medical records. Limb function was assessed using the Musculoskeletal Tumor Society (MSTS) score. RESULTS: Mean follow-up was 116 months (SD 59.2; 48 to 240) for the fibular strut allograft group and 113 months (SD 43.7; 60 to 192) for the bone cement group (p = 0.391). The rate of recurrence was not significantly different between the two groups (25% vs 21.4%). The rate of nononcological complications was 16.7% in the strut allograft group and 42.8% in the bone cement group. Degenerative joint disease was the most frequent nononcological complication in the cement group. The mean MSTS score of the patients was 92.4% (SD 11.5%; 73.3% to 100.0%) in the fibular strut allograft group and 74.2% (SD 10.5%; 66.7% to 96.7%) in the bone cement group (p < 0.001). CONCLUSION: Given the similar rate of recurrence and a lower rate of nononcological complications, fibular strut grafting could be recommended as a method of reconstructing the bone defect left by curettage of a GCT of the proximal femur. Cite this article: Bone Joint J 2022;104-B(2):297-301.

Does the adherence of distal femur parosteal osteosarcoma to the neurovascular bundle increase the rate of local recurrences?

BACKGROUND: Proximity of tumor to the neurovascular bundle (NVB) makes achieving a wide margin difficult. In low-grade parosteal osteosarcoma (POS), it is not clear whether adherence of tumor to NVB increases the rate of local recurrence (LR). In this study, we evaluated whether tumor adherence to the NVB increases the risk of LR in low-grade POS of the distal femur? HYPOTHESIS: We hypothesized that if the thin neurovascular barrier (the adventitia of the vessels and the epineurium of the nerve) prevents tumor penetration, the rate of LR should be comparable between the lesions with and without a continuous layer of healthy fatty tissue between the tumor and NVB. MATERIALS AND METHODS: In a retrospective survey, 30 patients with low-grade POS of the posterior aspect of the distal femur were evaluated for the proximity of mass to NVB. Based on the proximal to distal T1 axial MRI sections, the tumors were divided into two groups including the tumors with an uninterrupted (group A) and interrupted (group B) rim of fatty tissue between the mass and NVB. The rate of LR was compared between the two study groups. The concordance of MRI in detecting NVB adherence was checked with pathology specimen. RESULTS: Using MRI, we identified 16 cases in group A and 14 cases in group B. The MRI status of fatty rim was concordant with pathology specimen in 96.4% of cases. The mean follow-up period of the two groups was not statistically different (117±27.6 vs. 105.8±29.4 months, respectively, p=0.29). The other baseline characteristics of the two groups were statistically comparable, as well. The rate of LR was 12.5% (2 out of 16 patients) in group A and 14.3% (2 out of 14 patients) in group B (95% CI: 0.142-9.586, p=0.87). The 10-year recurrence-free survival was 87.5% for group A and 85.7% for group B (p=0.9). DISCUSSION: The absence of a continuous rim of fatty tissue between the tumor and NVB in MRI does not increase the risk of LR in low-grade POS of the distal femur. LEVEL OF EVIDENCE: IV.

Are Fibular Allograft Struts Useful for Unicameral Bone Cysts of the Proximal Humerus in Skeletally Mature Patients?

BACKGROUND: Although most unicameral bone cysts (UBCs) are either successfully treated or have healed by the time of skeletal maturity, a small proportion of patients will have persistent UBCs beyond the age of skeletal maturity. More reliable methods are needed to treat persistent UBCs in the humerus because these cysts are associated with a high risk of fracture due to thinning of the humeral cortex. In this study, we evaluated whether inserting a fibular strut allograft into the humerus would be associated with healing of the cyst and union of associated pathologic fractures in skeletally mature patients with a UBC of the proximal humerus. QUESTIONS/PURPOSES: (1) How effective is inserting a fibular strut allograft in the healing of proximal humerus UBCs in skeletally mature patients with bone cysts and associated fractures? (2) What are the functional results of this procedure? (3) What complications are associated with this procedure? METHODS: Between 2005 and 2018, we surgically treated 23 skeletally mature patients with persistent humeral UBCs and any of the following indications: a progressive cyst that was not responsive to aspiration and 2 to 3 steroid injections, a cyst with a pathologic fracture, and a cyst at high risk of fracture. Of those, patients with a cyst located in the proximal humerus and a defect length more than 6 cm (n = 18) were considered eligible to be treated with insertion of a fibular strut allograft through a hole created in the greater tuberosity. A further two patients were excluded because they were treated by other surgical methods. From the remaining 16 patients, two patients were lost to follow-up before 2 years and could not be analyzed in this study. Another two patients had incomplete datasets, leaving 12 for analyses in this retrospective study. Three patients presented with a pathologic fracture. Complete filling of the cysts with bone within 24 months was regarded as healing, and after 24 months it was classified as delayed healing. Cyst consolidation with small residual areas of osteolysis was considered healed with residual radiographic appearance. Fracture union was determined by the clear observation of at least three of four cortical views bridged by bone in the radiographic follow-up 3 months after the operation. Fractures in which the cortices were not bridged by bone after 3 months were regarded as a delayed union. The functional outcome of the patients was assessed by the Musculoskeletal Tumor Society (MSTS) scoring system, with a total score ranging from 0 to 30. A higher score was indicative of less pain and better function. MSTS scores were obtained through a chart review by an orthopaedist who was not involved in the care administered. RESULTS: At a median (range) follow-up of 57 months (33 to 87), the cyst was completely healed in nine patients and healed with residual cyst in the remaining three. Union was observed within 3 months in all patients who presented with a pathologic fracture. The median MSTS score of the patients was 30 (28 to 30). No postoperative complications such as persistent pain or re-fracture were observed. CONCLUSION: The primary goal of treating a UBC of the proximal humerus is to prevent fracture of the affected bone; insertion of a fibular strut graft in this study met this goal. Therefore, we believe a fibular strut allograft insertion is worth consideration when treating proximal humeral UBCs in skeletally mature patients. Further studies will be needed to determine whether this approach has benefits compared with other treatment options. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Evaluation of local and circulating osteopontin in malignant and benign primary bone tumors.

PURPOSE: The development of novel and efficient biomarkers for primary bone cancers is of grave importance. METHODS: The expression pattern of osteopontin (OPN) was investigated in the 153 patients with benign (n = 72) and malignant (n = 81) primary bone cancers. Both local and circulating OPN mRNA expression levels and their protein concentration in serum and tumor site were assessed using real-time qRT-PCR, ELISA, and immunohistochemistry techniques, respectively. As a control, 29 healthy individuals were considered. The number of 153 tumor tissue specimens and the 153 paired margins were taken on surgical resection from the patients. 153 blood samples were also drained from all participants, then peripheral blood mononuclear cells (PBMC) and sera were separated. RESULTS: The mean mRNA expression was significantly higher in all of the cancerous tissues than the paired margins and the PBMC of the patients than the controls. Consistently, the protein concentrations of OPN in serum and tumor tissues were significantly higher in the patients. Furthermore, the malignant cases had significantly elevated the mRNA levels and the protein compared to the benign cases. OPN could potentially differentiate the patients from the controls with 100% sensitivity and specificity in serum. Moreover, OPN could predict some of the malignant cases' clinicopathological features, including metastasis, recurrence, grade, and response to chemotherapy. CONCLUSIONS: In conclusion, OPN might be involved in the pathogenesis of primary bone tumors and can be considered as a potential biomarker to bone cancer diagnosis.