Dislocation of the hip remains a major complication after periacetabular tumour resection and endoprosthetic reconstruction. The position of the acetabular component is an important modifiable factor for surgeons in determining the risk of postoperative dislocation. We investigated the significance of horizontal, vertical, and sagittal displacement of the hip centre of rotation (COR) on postoperative dislocation using a CT-based 3D model, as well as other potential risk factors for dislocation. A total of 122 patients who underwent reconstruction following resection of periacetabular tumour between January 2011 and January 2020 were studied. The risk factors for dislocation were investigated with univariate and multivariate logistic regression analysis on patient-specific, resection-specific, and reconstruction-specific variables.Aims
Methods
There is an increased risk of dislocation of the hip after the resection of a periacetabular tumour and endoprosthetic reconstruction of the defect in the hemipelvis. The aim of this study was to determine the rate and timing of dislocation and to identify its risk factors. To determine the dislocation rate, we conducted a retrospective single-institution study of 441 patients with a periacetabular tumour who had undergone a standard modular hemipelvic endoprosthetic reconstruction between 2003 and 2019. After excluding ineligible patients, 420 patients were enrolled. Patient-specific, resection-specific, and reconstruction-specific variables were studied using univariate and multivariate analyses.Aims
Methods
The early mortality in patients with hip fractures from bony metastases is unknown. The objectives of this study were to quantify 30- and 90-day mortality in patients with proximal femoral metastases, and to create a mortality prediction tool based on biomarkers associated with early death. This was a retrospective cohort study of consecutive patients referred to the orthopaedic department at a UK trauma centre with a proximal femoral metastasis (PFM) over a seven-year period (2010 to 2016). The study group were compared to a matched control group of non-metastatic hip fractures. Minimum follow-up was one year.Aims
Methods
Extracorporeal irradiation of an excised tumour-bearing
segment of bone followed by its re-implantation is a technique used
in bone sarcoma surgery for limb salvage when the bone is of reasonable
quality. There is no agreement among previous studies about the
dose of irradiation to be given: up to 300 Gy have been used. We investigated the influence of extracorporeal irradiation on
the elastic and viscoelastic properties of bone. Bone was harvested
from mature cattle and subdivided into 13 groups: 12 were exposed
to increasing levels of irradiation: one was not and was used as
a control. The specimens, once irradiated, underwent mechanical
testing in saline at 37°C. The mechanical properties of each group, including Young’s modulus,
storage modulus and loss modulus, were determined experimentally
and compared with the control group. There were insignificant changes in all of these mechanical properties
with an increasing level of irradiation. We conclude that the overall mechanical effect of high levels
of extracorporeal irradiation (300 Gy) on bone is negligible. Consequently
the dose can be maximised to reduce the risk of local tumour recurrence. Cite this article:
We determined the efficacy of a devitalised autograft
(n = 13) and allograft (n = 16) cortical strut bone graft combined
with long-stem endoprosthetic reconstruction in the treatment of
massive tumours of the lower limb. A total of 29 patients (18 men:11
women, mean age 20.1 years (12 to 45) with a ratio of length of
resection to that of the whole prosthesis of >
50% were treated
between May 2003 and May 2012. The mean follow-up was 47 months
(15 to 132). The stem of the prosthesis was introduced through bone
graft struts filled with cement, then cemented into the residual
bone. Bone healing was achieved in 23 patients (86%). The mean Musculoskeletal
Tumour Society functional score was 85% (57 to 97). The five-year
survival rate of the endoprostheses was 81% (95% confidence intervals
67.3 to 92.3). The mean length of devitalised autografts and allografts
was 8.6 cm (5 to 15), which increased the ratio of the the length
of the stem of the prosthesis to that of the whole length of the
prosthesis from a theoretical 35% to an actual 55%. Cortical strut bone grafting and long-stem endoprosthetic reconstruction
is an option for treating massive segmental defects following resection
of a tumour in the lower limb. Patients can regain good function
with a low incidence of aseptic loosening. The strut graft and the
residual bone together serve as a satisfactory bony environment
for a revision prosthesis, if required, once union is achieved. Cite this article:
Previously, we showed that case-specific non-linear
finite element (FE) models are better at predicting the load to failure
of metastatic femora than experienced clinicians. In this study
we improved our FE modelling and increased the number of femora
and characteristics of the lesions. We retested the robustness of
the FE predictions and assessed why clinicians have difficulty in
estimating the load to failure of metastatic femora. A total of
20 femora with and without artificial metastases were mechanically
loaded until failure. These experiments were simulated using case-specific
FE models. Six clinicians ranked the femora on load to failure and
reported their ranking strategies. The experimental load to failure
for intact and metastatic femora was well predicted by the FE models (R2 =
0.90 and R2 = 0.93, respectively). Ranking metastatic
femora on load to failure was well performed by the FE models (τ =
0.87), but not by the clinicians (0.11 <
τ <
0.42). Both the
FE models and the clinicians allowed for the characteristics of
the lesions, but only the FE models incorporated the initial bone
strength, which is essential for accurately predicting the risk
of fracture. Accurate prediction of the risk of fracture should
be made possible for clinicians by further developing FE models.
Pathological fractures of the humerus are associated with pain, morbidity, loss of function and a diminished quality of life. We report our experience of stabilising these fractures using polymethylmethacrylate and non-locking plates. We undertook a retrospective review over 20 years of patients treated at a tertiary musculoskeletal oncology centre. Those who had undergone surgery for an impending or completed pathological humeral fracture with a diagnosis of metastatic disease or myeloma were identified from our database. There were 63 patients (43 men, 20 women) in the series with a mean age of 63 years (39 to 87). All had undergone intralesional curettage of the tumour followed by fixation with intramedullary polymethylmethacrylate and plating. Complications occurred in 14 patients (22.2%) and seven (11.1%) required re-operation. At the latest follow-up, 47 patients (74.6%) were deceased and 16 (25.4%) were living with a mean follow-up of 75 months (1 to 184). A total of 54 (86%) patients had no or mild pain and 50 (80%) required no or minimal assistance with activities of daily living. Of the 16 living patients none had pain and all could perform activities of daily living without assistance. Intralesional resection of the tumour, filling of the cavity with cement, and plate stabilisation of the pathological fracture gives immediate rigidity and allows an early return of function without the need for bony union. The patient’s local disease burden is reduced, which may alleviate tumour-related pain and slow the progression of the disease. The cemented-plate technique provides a reliable option for the treatment of pathological fractures of the humerus.
The use of allografts for the treatment of bone tumours in children is limited by nonunion and the difficulty of finding a suitable graft. Furthermore, appositional growth can’t be expected of an allograft. We used an overlapping allograft in 11 children, with a mean age of ten years (4 to 15), with a mean follow-up of 24.1 months (20 to 33). There were five intercalary and six intra-articular resections, and the tumours were in the femur in six cases and the humerus in five. Rates of union, times to union, remodelling patterns and allograft-associated complications were evaluated. No allograft was removed due to a complication. Of the 16 junctional sites, 15 (94%) showed union at a mean of 3.1 months (2 to 5). Remodelling between host and allograft was seen at 14 junctions at a mean of five months (4 to 7). The mean Musculoskeletal Tumor Society score was 26.5 of 30 (88.3%). One case of nonunion and another with screw protrusion required re-operation. Overlapping allografts have the potential to shorten time to union, decrease rates of nonunion and have positive appositional growth effect.
We review the treatment of pelvic Ewing’s sarcoma by the implantation of extracorporeally-irradiated (ECI) autografts and compare the outcome with that of other reported methods. We treated 13 patients with ECI autografts between 1994 and 2004. There were seven males and six females with a median age of 15.7 years (interquartile range (IQR) 12.2 to 21.7). At a median follow-up of five years (IQR 1.8 to 7.4), the disease-free survival was 69% overall, and 75% if one patient with local recurrence after initial treatment elsewhere was excluded. Four patients died from distant metastases at a mean of 17 months (13 to 23). There were three complications which required operative intervention; one was a deep infection which required removal of the graft. The functional results gave a mean Musculoskeletal Tumor Society score of 85% (60% to 97%), a mean Toronto extremity salvage score of 86% (69% to 100%) and a mean Harris hip score of 92 (67 to 100). We conclude that ECI grafting is a suitable form of treatment for localised and resectable pelvic Ewing’s sarcoma.
Between 1996 and 2003, 16 patients (nine female, seven male) were treated for a primary bone sarcoma of the femur by wide local excision of the tumour, extracorporeal irradiation and re-implantation. An additional vascularised fibular graft was used in 13 patients (81%). All patients were free from disease when reviewed at a minimum of two years postoperatively (mean 49.7 months (24 to 96). There were no cases of infection. Primary union was achieved after a median of nine months (interquartile range 7 to 11). Five host-donor junctions (16%) united only after a second procedure. Primary union recurred faster at metaphyseal junctions (94% (15) at a median of 7.5 months (interquartile range 4 to 12)) than at diaphyseal junctions (75% (12) at a median of 11.1 months (interquartile range 5 to 18)). Post-operatively, the median Musculoskeletal Tumour Society score was 85% (interquartile range 75 to 96) and the median Toronto Extremity Salvage score 94% (interquartile range 82 to 99). The Mankin score gave a good or excellent result in 14 patients (88%). The range of movement of the knee was significantly worse when the extracorporeally irradiated autografts were fixed by plates rather than by nails (p = 0.035). A total of 16 (62%) of the junctions of the vascularised fibular grafts underwent hypertrophy, indicating union and loading. Extracorporeal irradiation autografting with supplementary vascularised fibular grafting is a promising biological alternative for intercalary reconstruction after wide resection of malignant bone tumours of the femur.
We reviewed retrospectively the results in 211 consecutive patients who had undergone limb salvage for bone neoplasia with endoprosthetic reconstruction of the proximal femur (96), distal femur (78), proximal tibia (30) and total femur (7). Their mean age was 50 years (11 to 86) and the mean follow-up period was 37.3 months (1 to 204). A total of 35 (16.6%) prostheses failed. Overall, implant survival was 78% (95% confidence interval (CI) 0.29 to 0.54) at five years, 60% (95% CI 0.93 to 2.35) at ten years and 60% (95% CI 1.27 to 3.88) at 15 years. Survivorship of the limb was 97.6% (95% CI 1.73 to 3.35) at ten years. The gender, age, diagnosis and location of the tumour were not prognostic variables for failure. Modular endoprosthetic replacement in the lower limb is a durable long-term reconstructive option, with the implants generally outlasting the patient.