Low-grade central osteosarcoma (LGCOS), a rare type of osteosarcoma, often has misleading radiological and pathological features that overlap with those of other bone tumours, thereby complicating diagnosis and treatment. We aimed to analyze the clinical, radiological, and pathological features of patients with LGCOS, with a focus on diagnosis, treatment, and outcomes. We retrospectively analyzed the medical records of 49 patients with LGCOS (Broder’s grade 1 to 2) treated between January 1985 and December 2017 in a single institute. We examined the presence of malignant features on imaging (periosteal reaction, cortical destruction, soft-tissue invasion), the diagnostic accuracy of biopsy, surgical treatment, and oncological outcome.Aims
Methods
Dislocation rates are reportedly lower in patients requiring
proximal femoral hemiarthroplasty than for patients undergoing hip
arthroplasty for neoplasia. Without acetabular replacement, pain
due to acetabular wear necessitating revision surgery has been described.
We aimed to determine whether wear of the native acetabulum following
hemiarthroplasty necessitates revision surgery with secondary replacement
of the acetabulum after proximal femoral replacement (PFR) for tumour
reconstruction. We reviewed 100 consecutive PFRs performed between January 2003
and January 2013 without acetabular resurfacing. The procedure was
undertaken in 74 patients with metastases, for a primary bone tumour
in 20 and for myeloma in six. There were 48 male and 52 female patients,
with a mean age of 61.4 years (19 to 85) and median follow-up of
two years (interquartile range (IQR) 0.5 to 3.7 years). In total,
52 patients presented with a pathological fracture and six presented
with failed fixation of a previously instrumented pathological fracture.Aims
Patients and Methods
We investigated whether improvements in design have altered the outcome for patients undergoing endoprosthetic replacement of the distal femur after resection of a tumour. Survival of the implant and ‘servicing’ procedures have been documented using a prospective database, review of the design of the implant and case records. In total, 335 patients underwent a distal femoral replacement, 162 having a fixed-hinge design and 173 a rotating-hinge. The median age of the patients was 24 years (interquartile range 17 to 48). A total of 192 patients remained alive with a mean follow-up of 12 years (5 to 30). The risk of revision for any reason was 17% at five years, 33% at ten years and 58% at 20 years. Aseptic loosening was the main reason for revision of the fixed-hinge knees while infection and fracture of the stem were the most common for the rotating-hinge implant. The risk of revision for aseptic loosening was 35% at ten years with the fixed-hinge knee, which has, however, been replaced by the rotating-hinge knee with a hydroxyapatite collar. The overall risk of revision for any reason fell by 52% when the rotating-hinge implant was used. Improvements in the design of distal femoral endoprostheses have significantly decreased the need for revision operations, but infection remains a serious problem. We believe that a cemented, rotating-hinge prosthesis with a hydroxyapatite collar offers the best chance of long-term survival of the prosthesis.
