Aims. Calcium sulphate (CaSO. 4. ) is a resorbable material that can be used simultaneously as filler of a dead space and as a carrier for the local application of antibiotics. Our aim was to describe the systemic exposure and the wound fluid concentrations of vancomycin in patients treated with vancomycin-loaded CaSO. 4. as an adjunct to the routine therapy of bone and joint infections. Patients and Methods. A total of 680 post-operative blood and 233 wound fluid samples were available for analysis from 94 implantations performed in 87 patients for various infective indications. Up to 6 g of vancomycin were used. Non-compartmental pharmacokinetic analysis was performed on the data from 37 patients treated for an infection of the hip. Results. The overall systemic exposure remained within a safe range, even in patients with post-operative renal failure, none requiring removal of the pellets. Local concentrations were approximately ten times higher than with polymethylmethacrylate (PMMA) as a carrier, but remained below reported cell toxicity thresholds. Decreasing concentrations in wound fluid were observed over several weeks, but remained above the common minimum inhibitory concentrations for Staphylococcus up to three months post-operatively. . Conclusion. This study provides the first pharmacokinetic description of the local application of vancomycin with CaSO. 4. as a carrier, documenting slow release, systemic safety and a release profile far more interesting than from PMMA. In particular, considering in vitro data, concentrations of vancomycin active against staphylococcal biofilm were seen for several weeks. Cite this article: Bone Joint J 2017;99-B:1537–44

Introduction. The purpose of this study was to analyse the efficacy and complications associated with the use of Calcium Sulphate synthetic bone graft in a paediatric population. There are no published articles on the use in children. Materials & Methods. A retrospective review was undertaken of the notes, microbiology, and X-Rays of 17 cases (in 15 patients) of calcium sulphate use in paediatric patients. As well as patient demographic data, data collected included indication, use of additional agents (antibiotics), return to theatre, and wound complications. Major complications were also assessed for. Results. There were 17 cases, in 15 patients, in our case series where calcium sulphate synthetic bone graft was used. The average patient age was 12.0 years (range 5 years – 17 years). Indications for use included likely infection (12), possible infection (3), and 2 elective finger cases (enchondroma and osteotomy). The humerus was the most common target site (5), followed by the femur (4), tibia (3), calcaneum (2), finger (2) and metatarsal (1) also included. There were positive intra-operative microbiology samples for eleven cases (Staphylococcus aureus and Staphylococcus epidermidis). Antibiotics were used in all cases except the elective finger surgery, and choice ranged between vancomycin, gentamicin, or a combination of both. Two patients required return to theatre for management of ongoing deep infection, although one case was later deemed to be non-infective osteomyelitis. Seven patients had undergone debridements prior to the definitive one with calcium sulphate (5 without Calcium Sulphate, 2 with Calcium Sulphate). Three patients experienced wound issues in the form of discharge/leakage, all were managed with dressings and did not require return to theatre. Conclusions. Calcium Sulphate synthetic bone graft, with addition of antibiotics, is an efficacious treatment in the paediatric population and is not associated with any major complications. Wound discharge should be observed for, and patients/parents warned about this, but only as per the adult population

Aims. Delayed postoperative inoculation of orthopaedic implants with persistent wound drainage or bacterial seeding of a haematoma can result in periprosthetic joint infection (PJI). The aim of this in vivo study was to compare the efficacy of vancomycin powder with vancomycin-eluting calcium sulphate beads in preventing PJI due to delayed inoculation. Methods. A mouse model of PJI of the knee was used. Mice were randomized into groups with intervention at the time of surgery (postoperative day (POD) 0): a sterile control (SC; n = 6); infected control (IC; n = 15); systemic vancomycin (SV; n = 9); vancomycin powder (VP; n = 21); and vancomycin bead (VB; n = 19) groups. Delayed inoculation was introduced during an arthrotomy on POD 7 with 1 × 10. 5. colony-forming units (CFUs) of a bioluminescent strain of Staphylococcus aureus. The bacterial burden was monitored using bioluminescence in vivo. All mice were killed on POD 21. Implants and soft-tissue were harvested and sonicated for analysis of the CFUs. Results. The mean in vivo bioluminescence in the VB group was significantly lower on POD 8 and POD 10 compared with the other groups. There was a significant 1.3-log. 10. (95%) and 1.5-log. 10. (97%) reduction in mean soft-tissue CFUs in the VB group compared with the VP and IC groups (3.6 × 10. 3. vs 7.0 × 10. 4. ; p = 0.022; 3.6 × 10. 3. vs 1.0 × 10. 5. ; p = 0.007, respectively) at POD 21. There was a significant 1.6-log. 10. (98%) reduction in mean implant CFUs in the VB group compared with the IC group (1.3 × 10. 0. vs 4.7 × 10. 1. , respectively; p = 0.038). Combined soft-tissue and implant infection was prevented in 10 of 19 mice (53%) in the VB group as opposed to 5 of 21 (24%) in the VP group, 3 of 15 (20%) in the IC group, and 0% in the SV group. Conclusion. In our in vivo mouse model, antibiotic-releasing calcium sulphate beads appeared to outperform vancomycin powder alone in lowering the bacterial burden and preventing soft-tissue and implant infections. Cite this article: Bone Joint J 2024;106-B(6):632–638

Aims

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.

In bone and joint infections, several materials can be used for local antibiotic elution at site of infection. Polymethylmethacrylate (PMMA) cement is often used. Recently the use of antibiotic impregnated dissolvable synthetic pure calcium sulphate beads [Stimulan R]1 has been used as an alternative, due to several perceived advantages. We present our experience of using Calcium sulphate beads in infections involving the upper limb. From Jan 2012 to Jan 2015, we used Calcium sulphate beads in 7 complex upper limb infections including 1 elbow replacement, 2 infected non unions, 2 shoulder replacement, 1 wrist fusion and I ORIF elbow. We used combination of Vancomycin and Gentamicin in the beads, using manufacturer's mixing guide for optimum setting. Arthroplasty infections underwent explantation, addition of antibiotic impregnated calcium sulphate beads in the joint space, followed by a second stage, and systemic antibiotics. Fracture non-union cases had surgical debridement, calcium sulphate beads and systemic antibiotics. Follow up (6months to 2 years) indicate no recurrence of infection in any case. The most common organisms isolated were Coagulase negative staphylococcus and Staphylococcus aureus. Others included Group B Streptococcus, Serratia marscesens and Corynebacterium spp. In 2 of 7 cases there was significant drainage from the wound. This settled without further input. For fracture non-union fixation, there was no need to do second procedure to remove beads as they dissolve. In cases of staged revisions, the beads were inserted at first stage with microbiological clearance at 2nd stage. At present there are no reports in the literature of the use of this product in the upper limb. Our experience suggests use of dissolvable pure Calcium sulphate beads impregnated with selected antibiotics, is an effective adjunct to current treatments. Aseptic drainage has been reported and this was seen in some of our cases. It is postulated that the use of Calcium sulphate beads in more superficial joints may lead to more drainage. It may be necessary to avoid packing any beads in the subcutaneous spaces and using lower volumes in upper limb. Further work will include long-term follow up and any evidence of relapse or recurrence of infection

The management of chronic osteomyelitis is fraught with difficulties; a multi-disciplinary team approach is recommended for optimum outcome. Thorough debridement, dead space management and organism targeted antibiotic therapy the gives best clinical results. Calcium sulphate beads impregnated with antibiotic is an absorbable option for prolonged local antibiotic elution and dead space management. This study aims to analyse the early results of single stage management of osteomyelitis with antibiotic impregnated calcium sulphate beads. Following surgical debridement, calcium sulphate impregnated typically with tobramycin and/or vancomycin is inserted to obliterate the dead space. Intravenous antibiotics – typically teicoplanin and piperacillin-tazobactam – are administered until culture results permit rationalisation to narrow spectrum agents. Patients are followed up in Infectious Diseases and Orthopaedic clinics for a period of 12 months and discharged if quiescence is achieved. We conducted a retrospective analysis of our prospective database to identify patients treated with our single stage protocol for chronic osteomyelitis. We excluded patients that had (1) less than 6 months of follow up, (2) incomplete metal-ware removal, (3) patients lost to follow up. Fourteen patients (9 men, 5 women) with mean age of 41 (16–73) years and mean follow up of 9 (6–12) months were included in study. Eleven patients had previous surgeries involving internal fixation; the rest were primary osteomyelitis. Seven patients had washouts and removal of metal-ware procedures for osteomyelitis prior to referral to the bone infection service. Clinical, radiographic, and laboratory (microbiological, biochemical and haematological) methods were used to monitor response to treatment. Cierney-Mader classification determined that 8 patients were classed as type A (normal hosts); 4 as BS (systemically compromised); 2 as BLS (locally and systemically compromised). Anatomic analysis suggested 7 were Type 1 (medullary osteomyelitis); the remaining 7 were type 3 (localised disease). Five patients were staged IA; three each staged IIIA and IIIBS; and one each staged IBs, IBLS, IIIBLS. Staphylococcus Aureus was the commonest causative organism. Follow up radiograph monitoring indicated absorption of the beads by 3 months. There has been no evidence of recurrence based on clinical, radiographic and blood based parameters in all patients. Short-term results of single stage osteomyelitis treatment with calcium sulphate beads impregnated with antibiotics are promising

A multimodality approach is needed for management of infected joint replacement prostheses and infected skeletal metalwork. We present our results in six patients managed surgically with standard techniques, with the addition of a local antibiotic delivery system using absorbable Calcium Sulphate beads. A retrospective study was undertaken of 6 patients with established musculoskeletal infection in relation to existing metalwork. Two patients had infection in the hip replacement prosthesis, three had infected prosthetic knee joints and one had infection in a femoral locking plate. All were treated with extensive debridement, revision / retention of implants, parenteral antibiotics and local antibiotics. Patients were followed up in clinic for resolution of inflammatory markers and subsidence of signs of infection. Control of infection was achieved in five patients at average 19 months followup. One patient had persistent infection and has undergone further surgery. In this preliminary study, we found local antibiotic delivery using absorbable calcium sulphate beads to be an effective adjuvant to standard debridement, parenteral antibiotics and revision of implants

Bone and joint infections of the lower limbs cause significant morbidity for patients. Infection is a devastating complication for prosthetic joint replacements. In this large case series from a single centre in the NE of England, we present our experience of using antibiotic impregnated dissolvable synthetic pure calcium sulphate beads [Stimulan R]1 for local elution of antibiotics at the site of infection. At our centre, from August 2012 to Jan 2015, antibiotic impregnated dissolvable synthetic pure calcium sulphate beads [Stimulan R]1 was used for local elution of antibiotics in 45 patients with lower limb bone or joint infections. Tailored plans were made by Orthopedic surgeon and Microbiologist MDTs based on bacteria and sensitivities. Cases included 20 THR, 13 TKR, 5 Hemiarthroplasties, 4 tibial nonunions, 1 infected femoral plate and 2 paediatric osteomyelitis. Organisms isolated – Coagulase negative Staphs, Staph aureus, MRSA, E coli, Enterococcus, Enterobacter cloacae, Serratia and 1 Salmonella typhimurium!!. In our cases, a combination of Vancomycin and Gentamicin was added to Stimulan beads following manufacturer's mixing guide. In 2 cases, we added Ceftazidime to the beads and Daptomycin in 1 case. In bone infections, surgical debridement and systemic antibiotics were also needed. All arthroplasty infections underwent explantation with addition of antibiotic impregnated beads either at single stage or both stages of 2 stage revisions and systemic antibiotics. Follow up (ranging 9months to 2 years) indicates no failure so far. The beads caused no excessive wound drainage. There was no need to remove beads as they dissolve. In the cases where a staged revision was performed, the beads were inserted at first stage and there was microbiological clearance of infection at 2nd stage. Our series includes some experince in paediatric cases too. As far as we are aware, this is the largest series in the UK from a single centre reporting experience with Stimulan in infected bone and joints of the lower limbs. Our experience suggests use of dissolvable pure Calcium sulphate beads impregnated with carefully selected antibiotics, works as an effective adjunct to current treatments and offers flexibility with choice of antiobiotics that can be added locally. Acknowledgements. Biocomposites UK for supporting attendance at EBJIS. Authors control ownership of all data and analysis

Calcium sulphate (CaSO. 4. ) is a recognised form of delivery of antibiotic for the treatment of bone infection. Complications inherent in the rapid reabsorption are well recognised (predominantly that of wound breakdown and leakage). There is little data on the frequency of these complications. The purpose of this study was to quantify the incidence of wound leakage from CaSO. 4. and the service impact in orthopaedic surgery. Infective limb reconstruction cases managed with gentamicin impregnated CaSO. 4. between 2004–2012 were identified. Co-morbidities and factors influencing wound leakage were recorded. Medical and wound care notes were analysed. Episodes of delayed discharge and unscheduled clinic attendance due to wound leakage were recorded. 80 patients (18 female, 62 male), with a mean age of 45 years (18–80 years, median 46 years) underwent 84 procedures utilising CaSO. 4. 47 were in the tibia, 14 in the femur, 10 in the humerus. A mean of 36 mL (4–150 mL, median 22 ml, unknown in 18 cases) was used. 31 cases (37%) had post-operative wound leakage, the majority from the tibia(55%) and femur(25%). 21 cases (25%) leaked within the first week. Each 10 ml rise in CaSO. 4. volume lead to a 50% rise in leakage incidence. Leak duration ranged from 4 days–10 months. The majority leaked between 1–4 months before ceasing spontaneously and without specific treatment. 14 cases (17%) required a cumulative 32 unscheduled clinic appointments for leakage. Further surgery was required for infection in 7 cases (8.3%). Delayed discharge was not clearly attributable to CaSO. 4. The mode of skin closure and cultured organism did not affect leakage. CaSO. 4. has unpredictable leakage, but is present in 1/3 of patients. Volume of CaSO. 4. impacts on leakage. Leakage usually self-resolves and does not clearly impact on final outcomes. The cost impact of ongoing wound care and additional clinic appointments may be substantial

Chronic osteomyelitis is a challenging problem and a growing burden for the National Health Service. Conventional method of treatment is 2 stage surgery, with debridement and prolonged courses of antibiotics. Recently single stage treatment of chronic osteomyelitis is gaining popularity due decreased patient morbidity and cost effectiveness. Dead space management in single stage treatment is accomplished by either a muscle / myocutaneous or antibiotic loaded calcium sulphate beads. We analysed the cost effectiveness of two dead space management strategies in single stage treatment of osteomyelitis. Study is designed to analyse the health economics at 2 time points; 45 days post surgery and 2 years post surgery. We report preliminary results at 45 days post surgery. Setting – Level 1 trauma centre and university hospital. Approval – Ethics committee approved study. 10 patients in each group were retrospectively analysed through patient records. Each group was identified for standard demographics, duration of procedure, hospital stay, type and duration of postoperative antibiotics, number of out patient visits in first 45 days and recurrence of infection. Table attached details the results of both groups. In health technology assessment four quadrant model, CSB appears in quadrant II suggesting that it is more cost effective. Based on small data set and on assessment only evaluating cost, at 45 days assessment, antibiotic calcium sulphate beads from a Health Economic Cost Effectiveness Analysis offers a better economic outcome. This is holding constant the morbidity of the patients and effectiveness, assuming both treatments are standards of care, which is best evaluated at 24 months. Acknowledgements. Biocomposites for funding the cost of health economist

Introduction. Antibiotic loaded absorbable calcium sulphate beads (ALCSB) are an increasingly popular adjunct in the treatment of musculoskeletal infections including osteomyelitis and peri-prosthetic joint infections (PJI). Limited data exist regarding the clinical indications and biochemical outcomes of ALCSB in PJI cases. Aims. To determine the proportion of organisms that were sensitive to the gentamicin and vancomycin that we add to the ALCSB as a part of our treatment protocol and to determine the prevalence of postoperative hypercalcaemia when used for treatment of hip and knee DAIR (debridement and implant retention) and revision arthroplasty for PJI. Methods. A retrospective review of 160 hip and knee revisions using ALCSB performed between June 2015 and May 2018 at a tertiary unit was performed. 10–40 cc of ALCSB was used for each case containing vancomycin and gentamicin. Data recorded included patient demographics, comorbidities, indication for surgery, operative intervention, microbiological results and serum biochemistry for calcium levels. Results. The cohort consisted of 91 males and 69 females, with a mean age of 69.0 years (21.3 to 93.1) and mean BMI of 34.7(12.6 to 48.1). 56 (35%) had single-stage revision, 45 (28.1%) had first stage revision, 35 (21.9) had DAIR, 19 (11.9%) had second stage revision and 5 (3.1%) other procedures. Organisms included staphylococcus aureus (30.0%), culture-negative (27.5%), staphylococcus epidermidis (18.1%), and pseudomonas aeruginosa (3.1%). 54.3% were sensitive to both vancomycin and gentamicin, 25.0% to vancomycin only and 8.6% to gentamicin only. 11.9% (19/160) of patients had transient post-operative hypercalcaemia (normal range 2.2–2.7mmol/L), peaking at day 6–7 and resolved with hydration by day 10 postoperatively. Preoperatively, 26.9% had albumin <35 g/L and 49.3% had some degree of renal impairment with an eGFR <90 ml/min. Conclusion. The use of ALCSB allows local delivery of vancomycin and gentamicin in lower limb PJI. Organisms were sensitive to this antibiotic combination in 88% cases. Care must be taken to monitor calcium for 10 days post-operatively

Introduction:. Periprosthetic joint infection (PJI) is a devastating diagnosis that carries a significant rate of associated mortality and places a large burden on health care systems. Treatment protocols often include combined intravenous antibiotics and staged revision surgery with locally-delivered antibiotics via PMMA cement spacers and/or beads. One disadvantage of PMMA is the need for later removal. Antibiotic releasing Calcium Sulphate beads (CaSO. 4. ) have had promising results in revision joint surgery and are absorbable, making later removal unnecessary. We report on use in a tertiary referral centre in the UK and present our initial findings. Methods & Results:. CaSO. 4. beads containing 1 gram of Vancomycin and 240 mg of tobramycin per 10 cc was implanted in 12 patients between August 2012 and December 2012, all having undergone revision joint surgery for PJI. Of these patients; 7 were men and 5 women, mean age was 57 years (range 39–72) with a mean ASA grade of 2 (1–4). Indications were infected Total Hip Replacement (n = 7), infected Total Knee Replacement (n = 4) and infected metal on metal hip resurfacing (n = 1). Three procedures were emergencies, with the remainder being semi-elective procedures. One patient had single-stage revision THR. At latest follow up 10 patients had made a full recovery, with normal function and inflammatory markers. Two patients were awaiting a second stage revision procedure. Mean follow up was 2 months (1–4). Conclusion:. Implantable calcium sulphate beads are a new therapeutic agent for use in periprosthetic infection, with improved drug eluting properties and total absorption radiographically within two to three weeks. This study is the first to report its use in the UK, with encouraging data supporting its use in revision arthroplasty surgery

Optimal surgical management of proximal humeral fractures remains controversial. We report our experience and the study on our surgical technique for proximal humeral fractures and fracture-dislocations using locking plates in conjunction with calcium sulphate augmentation and tuberosity repair using high strength sutures. We used the extended deltoid-splitting approach for fracture patterns involving displacement of both lesser and greater tuberosities and for fracture-dislocations. We retrospectively analysed 22 proximal humeral fractures in 21 patients. 10 were male and 11 female with an average age of 64.6 years (Range 37 to 77). Average follow-up was 24 months. Fractures were classified according to Neer and Hertel systems. Pre-operative radiographs and CT scans in three and four-part fractures were done to assess the displacement and medial calcar length for predicting the humeral head vascularity. According to the Neer classification, there were 5 two-part, 6 three-part, 5 four-part fractures and 6 fracture-dislocations (2 anterior and 4 posterior). Results were assessed clinically with DASH scores, modified Constant & Murley scores and serial post-operative radiographs. The mean DASH score was 16.18 and modified Constant & Murley score was 64.04 at the last follow-up. 18 out of 22 cases achieved good clinical outcome. All the fractures united with no evidence of infection, failure of fixation, malunion, tuberosity failure, avascular necrosis or adverse reaction to calcium sulphate bone substitute. There was no evidence of axillary nerve injury. The CaSO4 bone substitute was replaced by normal appearing trabecular bone texture at an average of 6 months in all patients

Aim. Bone and implant-associated infections caused by microorganisms that grow in biofilm are difficult to treat because of persistence and recurrence. Systemic administration of antibiotics is often inefficient because the poor vascularization of the site of infection. This issue has led to the development of biomaterials capable to locally deliver high doses of therapeutic agents to the injured bone with minimal systemic effects. In this context, calcium sulphate/hydroxyapatite (CS/HA) bone graft substitutes are widely used being safe, osteoconductive and resorbable biomaterials that can be easily enriched with consistent amounts of antibiotics. In this in vitro study, the capability of the eluted antibiotics to select the tested bacterial strains for antibiotic resistance was evaluated to confirm the safe use of the product. Method. S. aureus, S. epidermidis and P. aeruginosa isolated in our Institute from bone and joint infection with different resistance phenotypes were used. 6 × 2.5 mm CS/HA discs were generated by pouring the antibiotic loaded formulations in a mold and were used as a modified disk diffusion test. The resistance selection was evaluated by subculturing cells growing on the edge of the zone of inhibition (ZOI) for seven days. Minimum inhibitory concentrations (MICs) of gentamicin and vancomycin were determined by broth microdilution method before and after the selection of resistance assay. In addition, MICs were assessed after seven day passage on antibiotic free agar plates to evaluate if eventual decrease of antibiotic susceptibility was stable or only transient. Results. Commonly, no adaptation in presence of both CS/HA formulations was observed by analysing ZOI on agar medium. The kinetic of decrease of the ZOI was similar between the strains, with the exception of gentamicin resistant staphylococci in presence of gentamicin loaded CS/HA, which was faster with respect to the susceptible strains. Conclusions. The present study shows that elution of gentamicin and vancomycin from CS/HA bone graft substitutes did not induce a decrease in susceptibility to these antibiotics in an in vitro setting, suggesting the safe use of the product

Aim. Since July 2013 our group has been using an antibiotic bone substitute, composed of calcium sulphate, hydroxyapatite and gentamicin sulphate (CSH + HA + GS), in the treatment of osteomyelitis (OM) in diabetic foot. The aim of this work was to evaluate the mid-term efficacy of this treatment regime on outcomes. A favourable outcome in diabetic foot includes no recurrence of OM, healed soft tissues and the ability to weight-bear. Method. To date we have used the CSH + HA + GS bone substitute in 24 diabetic patients with OM. In this study we reviewed patients treated from July 2013 to December 2014, in which we used CSH + HA + GS to treat OM of the forefoot, midfoot and hind foot, and evaluated how many patients are able to walk and fully weight-bear at present. We identified 11 pts treated during this time period; 1 with bilateral 1. St. metatarsal-head OM due to plantar ulcers, 5 with midfoot OM secondary to Charcot deformities and ulcers, 5 with hind foot OM due to pressure ulcers or Charcot deformity. We continuously monitored the patients for recurrence of OM, ulcers and soft tissue inflammation in our outpatient department. Results. Of the 11 patients, two died during follow up (both patients had calcaneal ulcers; one died in the 1. st. month and one in the 2. nd. month after treatment, both due to cardiovascular disease). For the remaining nine patients, we had an average of 25 (17–33) months follow-up. One patient did not heal, presenting with a persistent mid-foot lesion in a Charcot foot. Another patient with bilateral forefoot ulcers had a plantar ulcer recurrence under the left 1. st. metatarsal foot, 19 months after bone substitute application and primary healing. This patient is still weight-bearing on the right foot, as are the remaining 6 patients. In 7 patients (1 with bilateral forefoot, 4 with mid-foot and 3 with hind foot OM) no recurrence of OM or ulcers was observed. Conclusions. This study suggests that a CSH + HA + GS bone substitute can be used to treat diabetic foot OM. Our mid-term results show good clinical outcomes in terms of ulcer healing, no recurrence of OM and weight-bearing

Aim. Open fractures with bone loss and skin lesions carry a high risk of infection and complication. Treatment options are usually a two-stage approach (debridement, temporary stabilization with external fixation followed by open reduction and stabilization with plate). We describe an experience for a single stage procedure with an antibiotic eluting bone graft substitute (BGS) for prophylaxis of implant-related infection. Method. Between December 2014 and January 2016 were analysed the data of twenty-six patients with open fractures (Gustilo and Anderson grade I and II) or with skin lesion and high risk of contamination and bone loss. They where treated with debridement of soft tissue, closed reduction of fracture, placement of a plate augmented with BGS eluting antibiotic (gentamicin (1) and/or Vancomicin (2)). Ampicillin and sulbactam 3g three times daily was used as systemic antibiotic prophylaxis minimum for one week. Clinical outcome and radiographic bone defect filling were assessed by blinded observers. Results. From 2014 to 2015 twelve male and fourteen female with mean age 53yrs (24–77) were treated with plate and BGS. Fracture locations were four distal femur (m:4; f: 1), four tibial plateau (m:3; f:1), one proximal humerus (f:1), seven calcaneus (m:4; f: 3), one talus (m:1), four forearm (m:3), one elbow (f:1) and two phalanx (m: 2). Follow up was fourteen month (range: 3 – 26 months). During follow-up no implant-related infection was observed. One patient developed sterile seroma, which was treated conservatively. The calcium sulphate phase of BS dissolved in all cases within 4–6 weeks. Bone ingrowth was assessed at 1, 2, 3, 6 and 12 months. On six patients large bone was treated with a revision surgery (autologous cancellous bone graft combined with BGS and antibiotic. No complications were reported. Conclusions. We suggest the application of poly therapy for the treatment of bone defects. BGS eluting antibiotic is easy to use and offers the opportunity for a one-stage procedure and might reduce the risk of implanted-related infection and allow early joint mobilization. Good early clinical outcomes were observed in almost all cases. More studies and larger series are necessary to confirm the potential for the prophylaxis of infection in the treatment of open fractures. (1): CERAMENT™|G. (2): CERAMENT™|V”

Autologous bone grafting for bone defect reconstruction is associated with complications including donor site morbidity, infection risk, pain and surgical time. Therefore, bone graft substitutes provide an alternative for distinct indications and different characteristics with regard to their mechanical properties and resorption rates. In order to fill the loss of bone substance and to control the infection, we tried the efficacy of Cerament™G, a new absorbable composite of Calcium Sulphate and Hydroxyapatite with Gentamicin. We present 3 male patients aged between 45 and 68 years affected by post-traumatic severe septic non union of femur, tibia and foot. The first patient with femur fracture was involved in a car accident (mixed flora Acinetobacter Baumanii, MRSA and Klebsiella pneumoniae carbapenemase (KPC)-producing), the second patient with femur and foot fracture falled by height in a work accident (MRSA) and the third one had a chronic tibial osteomyelitis several years after a road accident (Pseudomonas Aeruginosa). All 3 patients had undergone previous surgery. The first patient had several operations including multiple bone resection and debridement with external fixator, occlusion of superficial femoral artery with arterial bypass and finally debridement with implantation of Cerament™ G with external fixator and long term antibiotic therapy. The other 2 patients were subjected to resection of tissue septic with debridement, implantation of Cerament™ G and soft tissue closure and systemic antibiotics. Clinical and radiographic outcome were assessed at final follow-up (mean 8 months; range 8–18). The follow-up was 8–18 months with examining clinical, radiographic, CT scan and laboratory tests. The patients had self-limiting fluid leakage. There was no recurrence of infection during the follow-up period. Bone ingrowth occurred in all cases with limb shortening. Cerament™ G gives good elution of antibiotic and allows bone ingrowth. The implantation of Cerament™ G was associated with good clinical outcomes and satisfactory bone consolidation. We acknowledge Antonella Esposito for septic nursing assistance

Aim. 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. Methods. 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. Results. We present our radiographic, µCT and histological results after a follow-up of twelve months. The bio-composite was clearly visible on all post-operative radiographs and resorbed over the next four months following the before described pattern of “halo sign” and “marble sign”. µCT images of the “halo sign” show degradation of the biocomposite starting at its surface, with the degradation products CaS and HA carried into the periphery of the bone void. µCT images of the “marble sign” showed the further degradation of the biocomposite from the surface to its core, leaving a “marble shaped” remnant of the biocomposite behind. These remnants are completely resorbed at 4.5 months. µCT scans at twelve and six months' reveal progression of trabecula bone formation. The histological results confirm the µCT findings. Conclusion. We have established a large animal model, which mimics the clinical situation and reproduces comparable radiographic post implantation features previously observed in clinical cases (including the “halo” and the “marble” sign). Using µCT imaging and histology we can describe and understand the biodegradation process and the bone formation capacity of the biocomposite in detail. *1 CERAMENTTM|G, BONESUPPORT, Lund, Sweden. *2 CERAMENTTM|G

Aim

Megaprosthesis have become a standard option in limb preserving surgery after bone resection in musculoskeletal tumors. Recently they have also been used in complex revision arthroplasty in cases with massive bone loss. The aim of this study was to analyze the incidence of periprosthetic joint infection (PJI) both in primary oncology cases and aseptic revision cases and analyze which are the significant risk factors for PJI with a special interest on the use of prophylactic antibiotic loaded calcium sulfate beads

We report our experience using a biodegradable calcium sulphate antibiotic carrier containing tobramycin in the surgical management of patients with chronic osteomyelitis. The patients were reviewed to determine the rate of recurrent infection, the filling of bony defects, and any problems with wound healing. A total of 193 patients (195 cases) with a mean age of 46.1 years (16.1 to 82.0) underwent surgery. According to the Cierny–Mader classification of osteomyelitis there were 12 type I, 1 type II, 144 type III and 38 type IV cases. The mean follow-up was 3.7 years (1.3 to 7.1) with recurrent infection occurring in 18 cases (9.2%) at a mean of 10.3 months post-operatively (1 to 25.0). After further treatment the infection resolved in 191 cases (97.9%). Prolonged wound ooze (longer than two weeks post-operatively) occurred in 30 cases (15.4%) in which there were no recurrent infection. Radiographic assessment at final follow-up showed no filling of the defect with bone in 67 (36.6%), partial filling in 108 (59.0%) and complete filling in eight (4.4%). A fracture occurred in nine (4.6%) of the treated osteomyelitic segments at a mean of 1.9 years (0.4 to 4.9) after operation.

We conclude that Osteoset T is helpful in the management of patients with chronic osteomyelitis, but the filling of the defect in bone is variable. Prolonged wound ooze is usually self-limiting and not associated with recurrent infection.

Cite this article: Bone Joint J 2014; 96-B:829–36