Giant cell tumour of bone.

Giant cell tumour of bone (GCTB) is a locally aggressive lesion that is difficult to treat as salvaging the joint can be associated with a high rate of local recurrence (LR). We evaluated the risk factors for tumour relapse after treatment of a GCTB of the limbs. A total of 354 consecutive patients with a GCTB underwent joint salvage by curettage and reconstruction with bone graft and/or cement or en bloc resection. Patient, tumour, and treatment factors were analyzed for their impact on LR. Patients treated with denosumab were excluded. There were 53 LRs (15%) at a mean 30.5 months (5 to 116). LR was higher after curettage (18.4%) than after resection (4.6%; p = 0.008). Neither pathological fracture (p = 0.240), Campanacci grade (p = 0.734), soft-tissue extension (p = 0.297), or tumour size (p = 0.872) affected the risk of recurrence. Joint salvage was possible in 74% of patients overall (262/354), and 98% after curettage alone (262/267). Of 49 patients with LR after curettage, 44 (90%) underwent repeated curettage and joint salvage. For patients treated by curettage, only age less than 30 years (p = 0.042) and location in the distal radius (p = 0.043) predicted higher LR. The rate of LR did not differ whether cement or bone graft was used (p = 0.753), but may have been reduced by the use of hydrogen peroxide (p = 0.069). Complications occurred in 15.3% of cases (54/354) and did not differ by treatment. Most patients with a GCTB can undergo successful joint salvage by aggressive curettage, even in the presence of a soft-tissue mass, pathological fracture, or a large lesion, with an 18.4% risk of local recurrence. However, 90% of local relapses after curettage can be treated by repeat joint salvage. Maximizing joint salvage is important to optimize long-term function since most patients with a GCTB are young adults. Younger patients and those with distal radius tumours treated with joint-sparing procedures have a higher rate of local relapse and may require more aggressive treatment and closer follow-up.

Comparison of Porous Tantalum Acetabular Implants and Harrington Reconstruction for Metastatic Disease of the Acetabulum.

BACKGROUND: The periacetabular region is a common location for metastatic disease. Although large lytic acetabular defects are commonly treated with a hip arthroplasty with a cemented component according to a Harrington-style reconstruction, the use of highly porous uncemented tantalum acetabular components has been described. Currently, there are no direct comparisons of these reconstructive techniques. The purpose of this study was to compare the outcomes of the Harrington technique and tantalum acetabular component reconstruction for periacetabular metastases. METHODS: From 2 tertiary sarcoma centers, we retrospectively reviewed 115 patients (70 female and 45 male) with an acetabular metastatic defect who had been treated between 2002 and 2015 with a total hip arthroplasty using either the cemented Harrington technique (78 patients) or a tantalum acetabular reconstruction (37 patients). The mean patient age was 61 years, and the most common Eastern Cooperative Oncology Group status was 3 (39 patients). The mean follow-up for surviving patients was 4 years. RESULTS: An additional surgical procedure was performed in 24 patients (21%). Harrington-style reconstructions were more likely to require a reoperation compared with tantalum reconstructions (hazard ratio [HR], 4.59; p = 0.003). The acetabular component was revised in 13 patients (11%); 5 patients (4%) underwent revisions that were due to loosening of the acetabular component. The 10-year cumulative incidence of revision of the acetabular component for loosening was 9.6% in the Harrington group and 0% in the tantalum group (p = 0.09). The mean Harris hip score significantly improved following reconstruction (31 to 67 points; p < 0.001), with no significant difference (p = 0.29) between groups. CONCLUSIONS: In patients with periacetabular metastatic disease treated with total hip arthroplasty, an acetabular reconstruction strategy utilizing highly porous tantalum acetabular components and augments successfully provided patients with a more durable construct with fewer complications compared with the cemented Harrington-style technique. LEVELS OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Quality Assurance in Custom Dental Devices: A Technologist's Perspective.

Manufacturing of custom-made dental devices such as removable dentures, fixed prosthodontics and orthodontics are subject to the requirements of the Medical Devices Directive (MDD). Many dental laboratories often enhance these requirements by implementing quality assurance procedures that then provide enhanced consistency. this paper provides a dental technologist's view of some of the systems currently being used in dental laboratories to provide a quality assured product and associated issues.

Credibility and Confidence in Your Dental Laboratory Work-How Quality Assurance Systems Can Be Used in the Manufacturing of Individual Custom-Made Dental Devices.

Manufacturing of custom-made dental devices such as removable dentures, fixed prosthodontics and orthodontics are subject to the requirements of the Medical Devices Directive (MDD). Many dental laboratories often enhance these requirements by implementing quality assurance procedures that then provide enhanced consistency. This paper provided a personal view of some of the systems currently being used in dental laboratories to provide a quality assured product and associated issues.

Uncemented tumor endoprostheses at the knee: root causes of failure.

UNLABELLED: Although cemented tumor endoprostheses are the most commonly used method for reconstruction of the distal femur or proximal tibia after resection of primary bone tumors, aseptic loosening remains a common complication. Uncemented tumor prostheses may minimize this problem. We investigated the root causes of prosthetic failure for 99 patients with a fixed-hinge, bone-ingrowth Kotz Modular Femur and Tibia Resection System endoprosthesis and compared complications that led to implant failure with results in the literature. Of the 74 distal femoral implants and 25 proximal tibial implants, 25 patients had complications that resulted in prosthetic failure (removal of the prosthesis) at a median of 24.1 (range, 0.8-72.6) months. Failure was caused by prosthesis (n = 18) or oncologic-related (n = 7) complications. However, limb-salvage was possible for 87 of 99 patients. Smaller stem size in the distal femur and longer bone resection length in the proximal tibia were significantly associated with increased risk of prosthetic failure by multivariate analysis. The risk of stem fracture (6 of 99 patients) and infection (10 of 99 patients) was higher than other reports, but aseptic loosening (2 of 99 patients) was uncommon. These results suggest that although the bone-ingrowth surface of this prosthesis leads to a very low aseptic loosening rate, the higher risk of stem fracture and infection must be addressed in future implant designs. LEVEL OF EVIDENCE: Therapeutic study, level IV-1 (case series).

Acetabular metastases: planning for reconstruction and review of results.

The treatment of acetabular bone metastases presents numerous clinical challenges including the necessity for careful patient selection for surgery, determination of the extent of bone destruction, and providing the patient with stable surgical reconstruction of the pelvis. There are relatively few patient series reported in the literature to inform treatment planning, surgical reconstruction techniques, and patient outcomes. We describe a rationale for assessment of patients with acetabular metastases and options for reconstruction. The three general principles for surgical treatment of metastatic bone disease (tumor removal, filling of the resultant bone defect, and bypass of the defect) are defined for acetabular metastases. The results of surgical treatment are described with reference to recent articles in the literature. The reconstruction of acetabular metastatic disease is a major surgical procedure with a significant risk of complications. The surgeon must be certain that the patient's longevity and potential improvement in quality of life justify the risk of the operation.

Large segment allograft survival is improved with intramedullary cement.

BACKGROUND AND OBJECTIVES: The most common cause of failure in large segment bone allografts used for oncologic reconstruction is allograft fracture. Reinforcement with pressurized intramedullary cement may improve the mechanical properties of allografts. METHODS: We reviewed the prospectively collected records of 45 patients who underwent en bloc resection of an extremity bone tumor and reconstruction using an allograft with intramedullary cement. RESULTS: Seven allografts were used for arthrodesis, 20 were intercalary, and 18 were osteochondral. Twenty eight of 45 patients were alive at a mean 5.8 years (SD 1.9; range 3-11.2) with 24 allografts in situ. In these 45 patients, there were four allograft fractures and four infections. Six of these complications resulted in allograft removal. The estimated 5-year allograft survival rate was 86% (95% confidence interval 74-98%). Seven patients required secondary autogenous bone grafting for non-unions. Function measured by the Toronto Extremity Salvage Score and the 1987 and 1993 Musculoskeletal Tumor Society Rating Scales demonstrated a consistent pattern with worse function in patients with osteochondral allografts and best function with intercalary allografts. CONCLUSIONS: These results suggest the addition of intramedullary cement to large segment bone allografts improves their survival by decreasing the fracture risk, particularly for allografts used for arthrodesis and intercalary reconstructions.