A clinical investigation into a new bone void filler is giving
first data on systemic and local exposure to the anti-infective
substance after implantation. A total of 20 patients with post-traumatic/post-operative bone
infections were enrolled in this open-label, prospective study.
After radical surgical debridement, the bone cavity was filled with
this material. The 21-day hospitalisation phase included determination
of gentamicin concentrations in plasma, urine and wound exudate, assessment
of wound healing, infection parameters, implant resorption, laboratory
parameters, and adverse event monitoring. The follow-up period was
six months. Objective
Method
We performed a randomised, radiostereometric study comparing two different bone cements, one of which has been sparsely clinically documented. Randomisation of 60 total hip replacements (57 patients) into two groups of 30 was undertaken. All the patients were operated on using a cemented Charnley total hip replacement, the only difference between groups being the bone cement used to secure the femoral component. The two cements used were Palamed G and Palacos R with gentamicin. The patients were followed up with repeated clinical and radiostereometric examinations for two years to assess the micromovement of the femoral component and the clinical outcome. The mean subsidence was 0.18 mm and 0.21 mm, and the mean internal rotation was 1.7° and 2.0° at two years for the Palamed G and Palacos R with gentamicin bone cements, respectively. We found no statistically significant differences between the groups. Micromovement occurred between the femoral component and the cement, while the cement mantle was stable inside the bone. The Harris hip score improved from a mean of 38 points (14 to 54) and 36 (10 to 57) pre-operatively to a mean of 92 (77 to 100) and 91 (63 to 100) at two years in the Palamed G and Palacos R groups, respectively. No differences were found between the groups. Both bone cements provided good initial fixation of the femoral component and good clinical results at two years.
To date, all surgical techniques used for reconstruction
of the pelvic ring following supra-acetabular tumour resection produce
high complication rates. We evaluated the clinical, oncological
and functional outcomes of a cohort of 35 patients (15 men and 20
women), including 21 Ewing’s sarcomas, six chondrosarcomas, three sarcomas
not otherwise specified, one osteosarcoma, two osseous malignant
fibrous histiocytomas, one synovial cell sarcoma and one metastasis.
The mean age of the patients was 31 years (8 to 79) and the latest
follow-up was carried out at a mean of 46 months (1.9 to 139.5)
post-operatively. We undertook a functional reconstruction of the pelvic ring using
polyaxial screws and titanium rods. In 31 patients (89%) the construct
was encased in antibiotic-impregnated polymethylmethacrylate. Preservation
of the extremities was possible for all patients. The survival rate
at three years was 93.9% (95% confidence interval (CI) 77.9 to 98.4),
at five years it was 82.4% (95% CI 57.6 to 93.4). For the 21 patients
with Ewing’s sarcoma it was 95.2% (95% CI 70.7 to 99.3) and 81.5%
(95% CI 52.0 to 93.8), respectively. Wound healing problems were
observed in eight patients, deep infection in five and clinically
asymptomatic breakage of the screws in six. The five-year implant survival
was 93.3% (95% CI 57.8 to 95.7). Patients were mobilised at a mean
of 3.5 weeks (1 to 7) post-operatively. A post-operative neurological
defect occurred in 12 patients. The mean Musculoskeletal Tumor Society
score at last available follow-up was 21.2 (10 to 27). This reconstruction technique is characterised by simple and
oncologically appropriate applicability, achieving high primary
stability that allows early mobilisation, good functional results
and relatively low complication rates. Cite this article:
The objective of this study is to determine an optimal antibiotic-loaded
bone cement (ALBC) for infection prophylaxis in total joint arthroplasty
(TJA). We evaluated the antibacterial effects of polymethylmethacrylate
(PMMA) bone cements loaded with vancomycin, teicoplanin, ceftazidime,
imipenem, piperacillin, gentamicin, and tobramycin against methicillin-sensitive Objectives
Methods
We describe a patient who developed a delayed-type hypersensitivity reaction to piperacillin/tazobactam in the cement beads and a spacer inserted at revision of total replacement of the left knee. We believe that this is the first report of such a problem. Our experience suggests that a delayed-type hypersensitivity reaction should be considered when a mixture of antibiotics such as piperacillin/tazobactam has been used in the bone cement, beads or spacer and the patient develops delayed symptoms of pain or painful paraesthesiae, fever, rash and abnormal laboratory findings in the absence of infection. The diagnosis was made when identical symptoms were induced by a provocation challenge test.
We present an update of the clinical and radiological results of 62 consecutive acetabular revisions using impacted morsellised cancellous bone grafts and a cemented acetabular component in 58 patients, at a mean follow-up of 22.2 years (20 to 25). The Kaplan-Meier survivorship for the acetabular component with revision for any reason as the endpoint was 75% at 20 years (95% confidence interval (CI) 62 to 88) when 16 hips were at risk. Excluding two revisions for septic loosening at three and six years, the survivorship at 20 years was 79% (95% CI 67 to 93). With further exclusions of one revision of a well-fixed acetabular component after 12 years during a femoral revision and two after 17 years for wear of the acetabular component, the survivorship for aseptic loosening was 87% at 20 years (95% CI 76 to 97). At the final review 14 of the 16 surviving hips had radiographs available. There was one additional case of radiological loosening and four acetabular reconstructions showed progressive radiolucent lines in one or two zones. Acetabular revision using impacted large morsellised bone chips (0.5 cm to 1 cm in diameter) and a cemented acetabular component remains a reliable technique for reconstruction, even when assessed at more than 20 years after surgery.
Bone cements produced by different manufacturers vary in their mechanical properties and antibiotic elution characteristics. Small changes in the formulation of a bone cement, which may not be apparent to surgeons, can also affect these properties. The supplier of Palacos bone cement with added gentamicin changed in 2005. We carried out a study to examine the mechanical characteristics and antibiotic elution of Schering-Plough Palacos, Heraeus Palacos and Depuy CMW Smartset bone cements. Both Heraeus Palacos and Smartset bone cements performed significantly better than Schering-Plough Palacos in terms of mechanical characteristics, with and without additional vancomycin (p <
0.001). All cements show a deterioration in flexural strength with increasing addition of vancomycin, albeit staying above ISO minimum levels. Both Heraeus Palacos and Smartset elute significantly more gentamicin cumulatively than Schering-Plough Palacos. Smartset elutes significantly more vancomycin cumulatively than Heraeus Palacos. The improved antibiotic elution characteristics of Smartset and Heraeus Palacos are not associated with a deterioration in mechanical properties. Although marketed as the ‘original’ Palacos, Heraeus Palacos has significantly altered mechanical and antibiotic elution characteristics compared with the most commonly-used previous version.
This study reviews the predisposing features, the clinical, and laboratory findings at the time of diagnosis and the results of single-stage revision of prosthetic replacement of the elbow for infection. Deep infection occurred in six of 305 (1.9%) primary total elbow replacements. The mean follow-up after revision was 6.8 years (6 months to 16 years) and the mean age at the time of revision was 62.7 years (56 to 74). All six cases with infection had rheumatoid arthritis and had received steroid therapy. The infective organism was
Revision arthroplasty after infection can often be complicated by both extensive bone loss and a relatively high rate of re-infection. Using allograft to address the bone loss in such patients is controversial because of the perceived risk of bacterial infection from the use of avascular graft material. We describe 12 two-stage revisions for infection in which segmental allografts were loaded with antibiotics using iontophoresis, a technique using an electrical potential to drive ionised antibiotics into cortical bone. Iontophoresis produced high levels of antibiotic in the allograft, which eluted into the surrounding tissues. We postulate that this offers protection from infection in the high-risk peri-operative period. None of the 12 patients who had two-stage revision with iontophoresed allografts had further infection after a mean period of 47 months (14 to 78).
Antibiotic prophylaxis is routinely administered during joint replacement surgery and may predispose patients to