Antibiotic-loaded biomaterials are often used in dead space management after excision of infected bone. This study assessed the chronological progression of new bone formation in infected defects, filled only with an absorbable, osteoconductive bone void filler with Gentamicin (1). 163 patients were treated for osteomyelitis or infected fractures with a single-stage excision, implantation of antibiotic carrier, stabilisation and wound closure. All had Cierny & Mader Type III (n=128) or Type IV (n=35) infection. No bone grafting was performed in any patient. Patients were followed up for a minimum of 12 months (mean 21.4 months; 12–56). Bone void filling was assessed on serial digitised, standardized radiographs taken immediately after surgery, at 6 weeks, 3, 6 and 12 months and then yearly. Data on defect size, location, degree of void filling, quality of the bone-biomaterial interface and material leakage were collected. Bone formation was calculated at final follow-up, as a percentage of initial defect volume, by determining the bone area on AP and lateral radiographs to the nearest 5%.Aim
Method
Nitrogen-containing bisphosphonates such as Zoledronic Acid (ZA) are used clinically for the treatment of skeletal diseases related with increased bone resorption. The gold standard is to administrate the drug through a systemic pathway, however this is often associated with high dosages, risk of side-effects, reduced site-specific drug delivery and hence, limited drug-effectiveness. A controlled local drug delivery, via a biomimetic bone graft, could be beneficial by direct and time-regulated application of significantly lower drug dosage at the site of interest. Thus, higher efficacy and reduced side-effects could be expected. In this experimental
A gentamicin-eluting biocomposite consisting of hydroxyapatite (HA) and calcium sulphate (CaS)*1 can provide effective dead space management and bone formation in chronic osteomyelitis. However, radiographic follow-up after implantation of this biomaterial has shown imaging features previously not described with other comparable bone graft substitutes. Last year we presented preliminary results with a follow-up of 6 months. Now we present the radiographic, µCT and histological one-year follow-up of the critical-size bone defect model in sheep. The aim of this study was to simulate the clinical situation in a large animal model to correlate different imaging techniques used in the clinic (Radiography, CT and MRI scans) with histological finding. Standardised bone defects were created in ten Merino-wool sheep (age two to four years). Large drill holes (diameter 2.5cm, depth 2cm, volume approx. 10ml) were placed in the medial femoral condyles of both hind legs and filled with gentamicin-eluting biocomposite. Initially surgery was carried out on the right hind leg. Three months later, an identical intervention was performed on the contralateral side. Animals were sacrificed at three and six weeks and 4.5, six and twelve months. Radiographs and MRI scans were taken immediately after sacrifice. Filled bone voids were harvested en-block and analysed using µCT, and histology.Aim
Methods
Eradication of infection in chronic osteomyelitis requires effective dead space management after debridement. Residual bacteria in biofilm may be resistant to normal levels of systemic antibiotic penetrating bone and will contribute to recurrence of osteomyelitis. This study evaluated a new antibiotic-loaded biocomposite in the eradication of chronic infection from bone defects. We report a prospective study of 100 patients with Cierny and Mader types III and IV chronic osteomyelitis, in 105 bones. Osteomyelitis followed open fracture or ORIF of closed fractures in 71%. Nine had concomitant septic arthritis. 80% had comorbidities (Cierny-Mader Class B hosts). Ten had infected non-unions. All patients were treated by a multidisciplinary team with a single-stage protocol including; debridement, multiple sampling, culture-specific systemic antibiotics, stabilisation, dead space filling with Cerament G™ and immediate primary skin closure. Stabilisation was required in 21 cases and 5 required joint fusion as part of the initial surgery. Plastic surgical skin closure was needed in 23 cases (18 free flaps). Patients were followed up for a minimum of one year (mean 19.5 months; 12–34).Aim
Patients and Method
A gentamicin-eluting biocomposite consisting of hydroxyapatite and calcium sulfate1 can provide effective dead space management in chronic osteomyelitis. However, radiographic follow-up after implantation of this novel material has consistently shown evidence of several unique imaging features previously not described with other comparable bone graft substitutes. Conclusive interpretation of these newly described imaging features is difficult as long term follow-up and histological correlation is not yet available. The aim of this study was to establish a large animal model, closely simulating the clinical situation in order to permit further analysis of imaging features in correlation with histological progression of bone remodelling. Standardised bone defects were created in ten Merino-wool sheep (age: two to four years). Large drill holes (diameter 2.5cm, depth 2cm, volume approx. 10ml) were placed in the medial femoral condyles of both hind legs and filled with a gentamicin antibiotic eluting bone graft substituteAim
Method
This study describes and correlates the radiographic and histologic changes which develop in a Gentamicin-eluting synthetic bone graft substitute 100 patients with COM were treated with a single stage procedure, including management of the dead space with insertion of a Gentamicin-eluting synthetic bone graft substitute Five patients had subsequent surgery, not related to recurrence of infection, which allowed biopsy of the implanted material. These biopsies were harvested between 12 days and 9 months after implantation. Tissue was fixed in formalin and stained with haematoxylin-eosin and immunohistochemically for bone matrix markers.Aim
Method
Chronic osteomyelitis may recur if dead space management, after
excision of infected bone, is inadequate. This study describes the
results of a strategy for the management of deep bone infection
and evaluates a new antibiotic-loaded biocomposite in the eradication
of infection from bone defects. We report a prospective study of 100 patients with chronic osteomyelitis,
in 105 bones. Osteomyelitis followed injury or surgery in 81 patients.
Nine had concomitant septic arthritis. 80 patients had comorbidities
(Cierny-Mader (C-M) Class B hosts). Ten had infected nonunions. All patients were treated by a multidisciplinary team with a
single-stage protocol including debridement, multiple sampling,
culture-specific systemic antibiotics, stabilisation, dead space
filling with the biocomposite and primary skin closure. Aims
Patients and Methods