Does the use of polymethyl-methacrylate cement after intralesional curettage of giant cell tumors of appendicular bone guarantee reduced local recurrence rates? A retrospective analysis.

PURPOSE: Polymethyl-methacrylate cement (PMMA) is often used as bone defect reconstruction material after surgical removal of giant cell tumors. The purpose of this study was to investigate if the application of PMMA improves the local recurrence rates for giant cell tumors (GCT) of appendicular bone treated with intralesional curettage. METHODS: A retrospective analysis of all appendicular GTCs treated at two major Danish sarcoma centres between the 1st of January 1998 and December 31st 2013; minimum follow-up of 3.0 years (median: 8.9; 1.3-18.7 years). Kaplan-Meier survival model, log-rank and multivariate Cox regression were used to calculate and compare local recurrence rates. p-values <0.05 were considered statistically significant. RESULTS: 102 patients (M59/F43), median age 31Y (11-84) were included in this study. The overall 3-years local recurrence-rate was 19.9% (95%CI: 11.9-27.9%); 91% had occurred within 3 years. In patients treated with intralesional curettage (n = 64), the 3-years recurrence-rate was 30.6% (95%CI: 18.8-42.4%), compared to 2.6% (95%CI: 0.0-7.8%) in patients treated with wide resection or amputation (n = 38), p < .001. The 3-years recurrence-rate for patients treated with intralesional curettage and reconstruction using PMMA was 29.0% (95%CI: 12.6-45.4%) and without PMMA: 31.8% (95%CI: 15.2-48.4%), p = .83. CONCLUSION: We found that the use of PMMA for bone defect reconstruction after intralesional curettage of GTCs in the appendicular skeleton did not ensure a reduced risk of local recurrence.

Occlusive wound closure prevents prolonged wound discharge-A randomised controlled trial in patients undergoing tumour resection and endoprosthetic reconstruction of the proximal femur because of metastatic bone disease.

Prolonged wound discharge is a common postoperative complication of orthopaedic procedures and a risk factor for implant-related infection. Occlusive wound closure methods have previously been suggested to reduce or even prevent this complication. We performed a randomised controlled trial on 70 patients who underwent surgical treatment for metastatic bone disease involving the proximal femur at our centre between January 2017 and August 2018. At conclusion of the tumour resection and endoprosthetic reconstruction procedure, patients were randomised to either occlusive wound closure (n = 35), using the Dermabond Prineo-22 skin closure system, or routine wound closure with conventional skin staples (n = 35). Skin closure with occlusive wound closure resulted in a lesser degree (P < .0001) and shorter duration of postoperative wound discharge (HR 2.89 [95% CI 1.6-5.05], P < .0018). Compared with staples, surgical wounds were already dry after a mean of 3.5 days [95% CI 3.2-3.9] versus 6.1 days [95% CI 4.8-7.3] (P < .0001). Prolonged wound discharge for 7 days or more was observed in 23% of patients (n = 8) in the Staples-group but was entirely absent in the occlusive wound closure group (P < .003). This study provides strong evidence that occlusive wound closure reduces frequency, degree, and duration of wound discharge in a patient population at particularly high risk for this complication.

Establishment and effects of allograft and synthetic bone graft substitute treatment of a critical size metaphyseal bone defect model in the sheep femur.

Assessment of bone graft material efficacy is difficult in humans, since invasive methods like staged CT scans or biopsies are ethically unjustifiable. Therefore, we developed a novel large animal model for the verification of a potential transformation of synthetic bone graft substitutes into vital bone. The model combines multiple imaging methods with corresponding histology in standardized critical sized cancellous bone defect. Cylindrical bone voids (10 ml) were created in the medial femoral condyles of both hind legs (first surgery at right hind leg, second surgery 3 months later at left hind leg) in three merino-wool sheep and either (i) left empty, filled with (ii) cancellous allograft bone or (iii) a synthetic, gentamicin eluting bone graft substitute. All samples were analysed with radiographs, MRI, µCT, DEXA and histology after sacrifice at 6 months. Unfilled defects only showed ingrowth of fibrous tissue, whereas good integration of the cancellous graft was seen in the allograft group. The bone graft substitute showed centripetal biodegradation and new trabecular bone formation in the periphery of the void as early as 3 months. µCT gave excellent insight into the structural changes within the defects, particularly progressive allograft incorporation and the bone graft substitute biodegradation process. MRI completed the picture by clearly visualizing soft tissue ingrowth into unfilled bone voids and presence of fluid collections. Histology was essential for verification of trabecular bone and osteoid formation. Conventional radiographs and DEXA could not differentiate details of the ongoing transformation process. This model appears well suited for detailed in vivo and ex vivo evaluation of bone graft substitute behaviour within large bone defects.

Treatment of benign and borderline bone tumors with combined curettage and bone defect reconstruction.

PURPOSE:: The management of bone defects following simple curettage of bone tumors is controversial and in light of the numerous emerging substitutes for bone grafts, we wished to review and report our experience with the use of cancellous allograft bone in the treatment of benign and borderline bone tumors. METHODS:: We reviewed the medical records of 164 consecutive patients with benign or borderline bone tumors treated with simple curettage at our orthopedic oncology center between 2009 and 2013. Postoperative radiological changes were evaluated by a modified Neer's classification in defects that were subsequently reconstructed with allograft bone ( n = 133). RESULTS:: Simple curettage with subsequent defect filling using allograft bone was the surgical procedure performed in the majority of our patients (81%) and was associated with a low overall 2.5-year local recurrence (LR; 9.8%) and complication rate (7.5%). The radiological appearance of the grafted defects was deemed satisfactory in 85% of cases, with signs of either complete or partial healing present 6-12 months postoperatively. With respect to pathology, we found high rates of LR in giant cell tumors (GCTs) of bone, simple cysts (SCs) in children, and preexisting local recurrent disease. We did not observe any allograft-related complications. CONCLUSIONS:: Simple curettage and bone defect reconstruction with bone allograft is a sufficient treatment for most benign bone lesions and is associated with a low complication rate. For high-risk entities, such as GCTs of bone, SCs in children, and recurrent disease, additional adjuvant treatment could be considered to avoid LR.

Comparison of two alternative wound closure methods for tumor arthroplasty of the hip: A frequency matched cohort study.

OBJECTIVE: To examine the effect of an alternative wound closure method after tumor arthroplasty of the hip compared to routine wound closure with skin staples. METHOD: Single center, frequency matched cohort study. We reviewed all patients who underwent tumor resection and endoprosthetic reconstruction of the proximal femur for pathologic fracture due to metastatic bone disease or malignant hematologic bone disease at our center between 2010 and 2014. All patients treated with occlusive wound closure (OWC), a combination of intradermal suture, Steri-Strips™, and an occlusive skin adhesive, during this period ( n = 35), were compared to an equally sized frequency matched group of patients having undergone routine wound closure with conventional skin staples. RESULTS: Patients with OWC were significantly faster to achieve dry wound status and consequently had significantly shorter administration of antibiotics and hospital stay. Compared to the patients with conventional wound closure with staples, their wounds were already dry after a mean 3.4 days (vs. 6.7 days [95%CI: 3-3.8 vs. 5.5-7.9], p < 0.0001), they received antibiotics for a mean 4.2 days (vs. 6.8 days [95%CI: 3.7-4.8 vs. 5.5-8.0], p < 0.0003) and their mean hospital stay was 6.3 days (vs. 8.0 days [95%CI: 5.5-7 vs. 6.8-9.3], p < 0.015). Prolonged wound discharge (PWD) for 7 days or more was observed in 34% of patients ( n = 12) in the conventional group, whereas this complication was completely absent ( n = 0) in the investigational group. For every three patients treated with OWC, one complication of PWD over 7 days is avoided (number needed to treat = 3). CONCLUSION: Compared to conventional staples, OWC appears to significantly reduce wound complications, use of antibiotics, and hospital stay in patients undergoing tumor arthroplasty procedures of the hip. As such, it may also contribute to a reduction of the substantially increased risk for prosthetic joint infection in this patient population.

Persistent wound drainage after tumor resection and endoprosthetic reconstruction of the proximal femur.

PURPOSE: To examine the prevalence of prolonged wound drainage (PWD) after tumor resection and endoprosthetic reconstruction of the hip. METHODS: Retrospective review of 86 consecutive patients with metastatic bone disease, malignant hematologic bone disease or bone sarcoma, treated with tumor resection and subsequent endoprosthetic reconstruction of the proximal femur, between 2010 and 2012, in a single center. RESULTS: PWD for 7 days or more was observed in 41 cases (48%). The wounds only ceased oozing after a mean of 8.4 days, leading to prolonged administration of prophylactic antibiotics (mean 8.7 days) and length of hospital stay (mean 10.2 days). Total femur replacement, bone sarcoma and additional pelvic reconstruction were identified as significant independent risk factors for an even longer duration of PWD. CONCLUSION: Compared to conventional hip arthroplasty, PWD appears to be significantly more prevalent in patients undergoing tumor arthroplasty procedures of the hip. Given the potentially increased risk for periprosthetic joint infection (PJI), increased awareness, identification and implementation of adequate strategies for prevention and treatment of this avoidable complication are warranted.