Search

Periprosthetic femoral fractures with long stem implants, poor bone stock and loosening pose a considerable surgical challenge. We describe a reconstruction technique using a custom-made mega-prosthesis, cement-linked to the femoral stem of a well-fixed existing implant. Clinical and radiological outcomes were assessed at our tertiary referral centre. There were 15 patients with a periprosthetic femoral fracture: 5 proximal and 10 distal femoral arthroplasties linked to existing femoral stems. The survival rate was 93.3% at a mean follow-up of 5.3 years (0.5-19.3) with 1 revision. We present a salvage technique with good intermediate-term outcomes for highly selected patients with complex periprosthetic femoral fractures, as another option to conventional fixation methods. Specifically, it allows immediate weight bearing and avoids some of the morbidity of total femoral arthroplasty or amputation., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: The objective of this study was to examine the degree of osteointegration into a hydroxyapatite-coated collar and relate this finding to aseptic loosening in patients with a distal femoral replacement used to treat primary bone cancer. Our hypothesis was that the implant collar would increase osteointegration and reduce the rate of aseptic implant loosening., Methods: Sixty-one patients treated with a primary cemented distal femoral prosthesis between 1992 and 2001 were included in this study. The mean duration of follow-up was 8.5 years (range, two to eighteen years). Extracortical bone growth into the grooved hydroxyapatite-coated collar was quantified radiographically. Histological sections through four hydroxyapatite-coated collars and four implants with no collar, retrieved following amputation due to local recurrence or at autopsy at a mean of 3.5 years (range, 1.4 to 6.1 years) after implantation, were evaluated as well., Results: Five (8%) of the implants were revised because of aseptic loosening, 3% of the implants fractured, and 3% were revised because of infection. Six limbs (10%) required amputation because of local tumor recurrence. On radiographs, osteointegration into the collar was seen to have occurred in 70% of the patients and did not correlate with sex, age, diagnosis, or length of time postoperatively. Histological analysis showed mature lamellar bone within the grooves of the hydroxyapatite-coated collar, and bone was observed in direct contact with the hydroxyapatite coating. Extracortical bone failed to make direct contact with the surface of the implants manufactured without a collar., Conclusions: The use of cemented distal femoral massive bone tumor prostheses with a hydroxyapatite-coated collar located at the shoulder of the implant was followed by a low (8%) rate of revision due to aseptic loosening. The use of hydroxyapatite grooved collars may lead to osteointegration of the implant shoulder (collar) and may reduce the rate of aseptic loosening.

Background: Patients with skeletal dysplasia are prone to degenerative hip disease thus requiring THA at a younger age than the general population. This is a technically demanding procedure with high complication and revision rates. Achieving good femoral fixation can be challenging because of the abnormal features of the hip., Questions/purposes: We therefore determined: (1) survivorship, (2) function, (3) radiographic findings, and (4) complications associated with a cementless custom-made femoral component used in THAs for patients with skeletal dysplasia and compared these parameters with those from other types of femoral fixation., Patients and Methods: Between 1992 and 2005, 40 THAs were performed in 25 patients with skeletal dysplasia using custom-made cementless femoral components. There were 15 men and 10 women with a mean age of 37.5 years (range, 18-61 years) and a mean height of 145 cm (range, 120-173 cm). Patients were followed clinically and radiographically for a minimum of 4.3 years (mean, 10.1 years; range, 4.3-18.2 years)., Results: The survivorship rates for the femoral and acetabular components were 92% and 70%, respectively, at 220 months. Revision arthroplasty was performed in four of 40 hips (10%). In two, the acetabular component was revised for aseptic loosening, one had both components revised for aseptic loosening, and one had an isolated femoral component revision for deep infection. The mean Harris hip score improved from 41 (range, 27-57) preoperatively to 80 (range, 51-94) at final followup. There were two intraoperative proximal femoral fractures and one dislocation., Conclusions: When compared with studies with equal followup, custom-made cementless components in THAs for patients with skeletal dysplasia apparently had lower revision and complication rates with comparable function and higher midterm survival.

Addressing severe proximal femoral bone loss in revision hip surgery is a challenging reconstructive problem. The use of modular proximal femoral megaprostheses is one of many available options to address this. This is a retrospective review of 15 patients who had undergone limb salvage at our institution using a modular proximal femoral replacement. There were 8 males and 7 females with a mean age of 67 years (34 to 85) and a mean follow-up of 60 months (1 to 99). Indications included re-implantation for deep infection in nine patients, aseptic loosening in three, periprosthetic fracture in two and painful excision arthroplasty in one. Mean Harris hip score increased from 28 (13 to 49) pre-operatively to 69 (39 to 85) at final follow-up (paired t-test, p < 0.0001) and mean Toronto Extremity Salvage score increased from 26% (14 to 40) to 71% (35 to 82) (paired t-test, p < 0.0001). Prosthesis survival with revision as the endpoint was 87% at 5 years. There were two dislocations (14%) and there was failure to eradicate deep infection in two. Modular proximal femoral replacement provided good function and versatility with an acceptable complication rate for patients with severe proximal femoral bone loss with or without infection.

We treated three patients with aneurysmal bone cysts and seven with giant cell tumours who presented with a large osteolytic lesion in peri-articular areas of the knee. The patients age ranged from 8 to 49 years (mean 25 years). The average tumour volume was measured at 39.8 cm(3) (range 18 to 65 cm(3)). The tumour cavities were treated with curettage, phenolisation and application of a composite bone graft substitute containing 35% calcium-sulphate hemihydrate and 65% hydroxyapatite granules. All patients were followed up for 4.0 to 5.2 years (mean 4.5 years). Tumour recurrence was noted in two cases. In the remaining patients consolidation of the lesion was considered complete at a mean of 4.5 months (3-6.5 months). During follow-up no deformities developed and no radiological signs of joint degeneration were noted. All patients regained close to normal function, with a mean Musculoskeletal Tumour Society Rating Score of 95.1%. Due to their good osteoconductive abilities, composite synthetic bone graft substitute combining porous hydroxyapatite with calcium-sulphate appears to be an effective alternative to autologous cancellous bone graft in the treatment of large osteolytic lesions in peri-articular areas around the knee joint. They bear major advantages through ubiquitous availability and the avoidance of morbidity associated with iliac crest harvest. Concerns remain as the radio-opaque appearance of the bone graft substitute may potentially delay the detection of tumour recurrence.

Background: Aseptic loosening of massive bone tumor implants is a major cause of prosthesis failure. Evidence suggests that an osteointegrated hydroxyapatite (HA)-coated collar would reduce the incidence of aseptic loosening around the cemented intramedullary stem in distal femoral bone tumor prostheses. Because these implants often are used in young patients with a tumor, such treatment might extend the longevity of tumor implants. Questions/purposes We asked whether (1) HA-coated collars were more likely to osteointegrate; (2) HA collars were associated with fewer progressive radiolucent lines around the stem-cement interface; and (3) HA-coated collars were associated with less bone loss at the bone-shoulder implant junction? Methods: Twenty-two patients were pair-matched to one of two groups-either (1) implants with a HA-coated ingrowth collar (HA Collar Group); or (2) implants without an ingrowth collar (Noncollar Group). Age, sex, and length of followup were similar in both groups. HA-coated collars were developed and used at our institution from 1992 to address the high failure rate attributable to aseptic loosening in patients with massive bone tumor implants. Before this, smooth titanium shafts were used routinely adjacent to bone at the transection site. The minimum followup was 2 years (mean, 7 years; range, 2-12 years). Radiographs obtained throughout the followup period were analyzed and osteointegration at the shaft of the implant quantified. Radiolucent line progression around the cemented stem was semi-quantitatively assessed and cortical bone loss at the bone-shoulder implant junction was measured during the followup period. Results: Comparison of the most recent radiographs showed nine of 11 patients had osteointegrated HA collars, whereas only one patient in the Noncollar Group had osteointegration (p > 0.001). The radiolucent line score quantified around the cemented stem was lower in the HA Collar Group when compared with the Noncollar Group (p = 0.001). Results showed an increase in cortical bone loss at the bone-shoulder implant junction in the Noncollar Group when compared with the HA Collar Group (p < 0.001). Conclusions: Osteointegration at the implant collar resulted in fewer radiolucent lines adjacent to the intramedullary cemented stem and decreased cortical bone loss immediately adjacent to the transection site. These results suggest that the HA collar may help reduce the risk of aseptic loosening in patients with this type of implant, but longer followup and a larger prospective comparison series are necessary to prove this more definitively. [ABSTRACT FROM AUTHOR]