Rotating-hinge knee prostheses are commonly used to reconstruct the distal femur after resection of a tumour, despite the projected long-term burden of reoperation due to complications. Few studies have examined the factors that influence their failure and none, to our knowledge, have used competing risk models to do so. The purpose of this study was to determine the risk factors for failure of a rotating-hinge knee distal femoral arthroplasty using the Fine-Gray competing risk model. We retrospectively reviewed 209 consecutive patients who, between 1991 and 2016, had undergone resection of the distal femur for tumour and reconstruction using a rotating-hinge knee prosthesis. The study endpoint was failure of the prosthesis, defined as removal of the femoral component, the tibial component, or the bone-implant fixation; major revision (exchange of the femoral component, tibial component, or the bone-implant fixation); or amputation.Aims
Methods
Although internal hemipelvectomy is associated with a high incidence of morbidity, especially wound complications, few studies have examined rates of wound complications in these patients or have identified factors associated with the consequences. The present study aimed to: 1) determine the rate of wound and other complications requiring surgery after internal hemipelvectomy; and 2) identify factors that affect the rate of wound complications and can be used to stratify patients by risk of wound complications. The medical records of 123 patients undergoing internal hemipelvectomy were retrospectively reviewed, with a focus on both overall complications and wound complications. Logistic regression analyses were performed to examine the association between host, tumour, and surgical factors and rates of postoperative wound complications.Aims
Methods
We reviewed our initial seven-year experience
with a non-invasive extendible prosthesis in 34 children with primary bone
tumours. The distal femur was replaced in 25 cases, total femur
in five, proximal femur in one and proximal tibia in three. The
mean follow-up was 44 months (15 to 86) and 27 patients (79%) remain
alive. The prostheses were lengthened by an electromagnetic induction
mechanism in an outpatient setting and a mean extension of 32 mm
(4 to 80) was achieved without anaesthesia. There were lengthening
complications in two children: failed lengthening in one and the
formation of scar tissue in the other. Deep infection developed
in six patients (18%) and local recurrence in three. A total of
11 patients required further surgery to the leg. Amputation was
necessary in five patients (20%) and a two-stage revision in another.
There were no cases of loosening, but two patients had implant breakage
and required revision. The mean Musculoskeletal Tumor Society functional
score was 85% (60% to 100%) at last known follow-up. These early
results demonstrate that the non-invasive extendible prosthesis
allows successful lengthening without surgical intervention, but
the high incidence of infection is a cause for concern.
