Management of bone defects is a common surgical challenge encountered following any high energy trauma. Femur fractures with bone loss account for 22% of all the fractures with bone loss/defect, and 5% to 10% of distal femur fractures are open injuries. It was estimated in 2008, that, more than 4.5 million open fractures occur annually in India. In this retrospective study, patients who received bone allograft from our tissue bank between May 2012 and September 2015 were analysed. Of the 553 allografts issued, at that point in time, 26 were used in patients who underwent reconstruction for distal Femur fractures primarily. Fractures with defect or bone loss from 12 cc (1cm) to 144 cc (12cm) were treated with either Internal or External fixation and bone allograft. Morcellised cancellous, or a cortical strut, were used to fill or reconstruct the defect or void. The radiological outcome in terms of fracture union was assessed and Knee society score was used to assess the functional outcome. Complications such as non- union, infection, stiffness and need of revision or additional procedures were also assessed. Osseous consolidation was achieved in all the 26 patients with a Median time of 24 weeks (16 to 60). The Median Functional Knee Society Score was 80, indicating satisfactory functional outcome. Infection was noted in one patient, but it was not attributed to the allograft. Additional minor procedures like bone marrow infiltration, corticotomy for bone lengthening were required in 10 patients. Our studycomprises the largest group of patients treated primarily with Allograft to reconstruct or fill the void of bone loss encountered with distal Femur fracture. Reconstruction of massive bone defects, in patients of distal Femur fractures, with bone allograft, shows encouraging results. The surgeon can achieve the goal of restoring form and function of these difficult injuries in a single stage and the technique will provide the freedom to reconstruct the bony defect up to 150 cc (12 cm length) and recreate the anatomy to near normal. This allows for early mobilisation of patients and restoration of their daily routine at the earliest

Structural bone allografts are a viable option in reconstructing massive bone defects in patients following musculoskeletal (MSK) tumour resection and revision hip/knee replacements. To decrease infection risk, bone allografts are often sterilised with gamma-irradiation, which consequently degrades the bone collagen connectivity and makes the bone brittle. Clinically, irradiated bone allografts fracture at rates twice that of fresh non-irradiated allografts. Our lab has developed a method that protects the bone collagen connectivity through ribose pre-treatment while still undergoing gamma-irradiation. Biomechanical testing of bone pretreated with our method provided 60–70% protection of toughness and 100% protection of strength otherwise lost with conventional irradiation. This study aimed to determine if the ribose-treated bone allografts are biocompatible with host bone. The New Zealand White rabbit (NZWr) radius segmental defect model was used, in which 15-mm critically-sized defects were created. Bone allografts were first harvested from the radial diaphysis of donor female NZWr, and treated to create 3 graft types: C=untreated controls, I=conventionally-irradiated (33 kGy), R=our ribose pretreated + irradiation method. Recipient female NZWr (n=24) were then evenly randomised into the 3 graft groups. Allografts were surgically fixed with a 0.8-mm Kirschner wire. Post-operative X-rays were taken at 2, 6, and 12 weeks, with bony healing assessed by a blinded MSK radiologist using an established radiographic scoring system. The reconstructed radii were retrieved at 12 weeks and analysed using bone histomorphometry and microCT. Kruskal-Wallis and Mann-Whitney tests were utilised to compare groups, with statistical significance when p<0.05. Radiographic analysis revealed no differences in periosteal reaction and degree of osteotomy site union between the groups at any time point. Less cortical remodeling was observed in R and I grafts compared to untreated controls at 6 weeks (p=0.004), but was no longer evident by 12 weeks. Radiographic union was achieved in all groups by 12 weeks. Histologic and microCT analysis further confirmed union at the graft-host bone interface, with the presence of mineralising callus and osteoid. Histomorphometry also showed the bridging external callus originated from host bone periosteum and a distinct cement line between allograft and host bone was present at the union site. Previous studies have shown that the presence of non-enzymatic glycation end products in bone can impair fracture healing. However, these studies investigated bony healing in the setting of diabetic states. Our findings showed that under normal conditions, ribose pretreated grafts healed at rates similar to controls via mechanisms also seen in retrieved human allografts clinically in use. These findings that grafts pretreated with our method are biocompatible with host bone in the rabbit help to further advance this technology for clinical trials

INTRODUCTION. Allograft reconstruction after resection of primary bone sarcomas has a non-union rate of approximately 20%. Achieving a wide surface area of contact between host and allograft bone is one of the most important factors to help reduce the non-union rate. We developed a novel technique of haptic robot-assisted surgery to reconstruct bone defects left after primary bone sarcoma resection with structural allograft. METHODS. Using a sawbone distal femur joint-sparing hemimetaphyseal resection/reconstruction model, an identical bone defect was created in six sawbone distal femur specimens. A tumor-fellowship trained orthopedic surgeon reconstructed the defect using a simulated sawbone allograft femur. First, a standard, ‘all-manual’ technique was used to cut and prepare the allograft to best fit the defect. Then, using an identical sawbone copy of the allograft, the novel haptic-robot technique was used to prepare the allograft to best fit the defect. All specimens were scanned via CT. Using a separately validated technique, the surface area of contact between host and allograft was measured for both (1) the all-manual reconstruction and (2) the robot-assisted reconstruction. All contact surface areas were normalized by dividing absolute contact area by the available surface area on the exposed cut surface of host bone. RESULTS. The mean area of contact between host and allograft bone was 24% (of the available host surface area) for the all-manual group and 76% for the haptic robot-assisted group (p=0.004). CONCLUSIONS. This is the first report to our knowledge of using haptic robot technology to assist in structural bone allograft reconstruction of defects left after primary bone tumor resection. The findings strongly indicate that this technology has the potential to be of substantial clinical benefit. Further studies are warranted

Osteogenic augmentation is required in various orthopaedic conditions. Autograft is the gold standard but has limitations of increased morbidity and limited amount. Bone graft substitutes are costly and limited and don't integrate with host bone. Deep freezed allografts are a viable option, though not widely used in India and there are sparse reports in literature. This paper studies early efficacy of deep freezed bone allografts in treatment of fractures requiring bone graft. This is a prospective descriptive study. Strict inclusion and exclusion criteria as per standard guidelines were followed. We have a in-house facility of gamma irradiated deep freezed allografts available in hospital. 20 patients with comminuted fracture, delayed / malunion / nonunion, depressed intra articular fractures were operated during one year and followed up for at least 24 weeks. Sloof's Criteria was used for assessing osteointegration of grafts. Efficacy was authenticated by observing complications like serous discharge from surgical site, infection (superficial/deep), rejection of graft, clinical and radiological integration of graft, maintenance of articular reduction etc. Allografts have not only accepted well but fractures have healed and bone integration is at various stages. Only one patients got infected (5%). The overall success rate in terms of adequate osteointegration is 95 %. 19 out of 20 patients in our study group had either attained or at various stages of osteointegration and healing. We concluded that deep freezed bone allografts is a viable option in patients with fractures requiring bone grafts, thus give satisfactory surgical outcome, with no serious side effects

A radiation sterilisation dose (RSD) of 25 kGy is commonly recommended for sterilisation of allograft bone. However, the mechanical and biological performance of allograft bone is gamma dose-dependent. Therefore, this study aimed to apply Method 1 – ISO 11137–2: 2006 to establish a low RSD for frozen bone allografts. Two groups of allograft bones were used: 110 femoral heads (FH) and 130 structural and morselized bones (SMB). The method included the following stages: bioburden determination using 10 FHs and 30 SMBs; verification dose selection using table six in the ISO standard and bioburden; the verification dose was used to irradiate 100 samples from each group; then irradiated bone segments were tested for sterility. The criterion for accepting the RSD as valid is that there must be no more than two non-sterile samples out of 100. The radiation sterilisation dose is then established based on table five, ISO 11137– 2: 2006. The bioburden of both types of frozen allograft was zero. The verification dose chosen was 1.3 kGy. Two hundred bone segments were irradiated at 1.3 kGy. The average delivery gamma dose was 1.23 kGy (with minimum dose of 1.05 kGy maximum dose of 1.41kGy), which is acceptable according to the ISO standard. Sterility tests achieved 100% sterility. Accordingly, 11 kGy was established as a valid RSD for those frozen bone allografts. A reduction in the RSD from 25 kGy to 11 kGy will significantly improve bone allograft mechanical and biological performance because our data show that this dose level improves the mechanical toughness and osteoclast activity of the allograft by more than 10 and 100 percent, respectively, compared with bone allografts irradiated at 25 kGy. A low RSD of 11 kGy was established for allograft bones manufactured at Queensland Bone Bank by applying dose validation method 1 (ISO 11137.2-2006) that is internationally accepted

Objectives. Despite promising results have shown by osteogenic cell-based demineralized bone matrix composites, they need to be optimized for grafts that act as structural frameworks in load-bearing defects. The aims of this study is attempt to assess the effects of laser perforations on osteoinduction in cortical bone allografts. Methods. Sixteen wistar rats were divided into two groups according to the type of structural bone allograft; the first: partially demineralized only (Donly) and the second: partially demineralized laser-perforated (DLP). Trans-cortical holes were achieved by Er:YAG laser at a wave length of 2.94 µm in four rows of three holes approximated cylindrical holes 0.5 mm in diameter, with centres 2.5 mm apart. Histologic and histomorphometric analysis were performed at 12 weeks. Results. Statistical analysis showed significant differences between the 2 groups at 3 months. Results showed that partially demineralized laser-perforated grafts had substantially higher incorporation by woven bone than partially demineralized grafts; yet this difference at the interface gap remained insignificant. In DLP allografts healing at the junction was more complete and a wider area was in contact with host and graft surfaces. Conclusions. Based on the results of this study, it may be concluded that surface changes induced by Er:YAG laser, accelerated bone healing with good osteoinduction results and the process might have improved, if they could have been supplemented with the proper stipulations

Introduction. BAG-S53P4 has similar mechanical properties as cortical bone tissue and can be used as an additive to bone allografts. The aim of this study was to evaluate the effect of adding BAG-S53P4 to chemically treated allografts with controlled grain size distribution. Methods. Allografts were prepared and chemically cleaned under sterile conditions. 30 samples were mixed with BAG-S53P4 additive (BG) and compared to a control group (CG) with similar grain size distribution and composition in weight. All samples underwent a uniaxial compression test after compaction with a dropped weight apparatus. The yield limit was determined by a uniaxial compression test and density was recorded. The two groups were tested for statistical differences with the student's t-Test. Results. Adding BAG-S53P4 to the chemically treated allografts with controlled grain size distribution did not affect the yield limit after compaction. No statistically significant difference regarding the yield limit could be found between CG and BG after compaction (p=0.432).). The yield limit yield limit showed an increase of approximately 96% in CG and 93 % in BG, which confirms the importance of impacting bone chips used for load bearing applications like in hip arthroplasty. Conclusions. Adding BAG-S53P4 seems to have a less profound impact on the yield stress limit. In BG particles smaller than 4 mm were substituted with BAG-S53P4. Achieving a high density may not be the major goal for the bone remodeling process as it may actually obstruct new osteocytes from growing into the allograft material. Adding BAG-S53P4 seems to have limited impact on the yield stress limit. From a biomechanical point of view, BAG-S53P4 can be used as a substitute in total hip replacement if access to bone allograft material is limited

Aims. To evaluate the place of the massive prostheses in the most complex periprosthetic infections cases (PJis). Method. Between 2011 and 2017, 516 hip and knee revisions for periprosthetic infections had been performed in our hospital by the same senior surgeon. We report a prospective series of 58 patients treated between 2011 and the end of 2017. 26 males and 32 females with on average 69,4 years old (38–86). Infection involved TKA in 39 cases (26 TKA revisions, 11 primary TKA), THA in 18 cases (10 revisions, 7 primary THA), a femoral pseudoarthrosis with posttraumatic gonarthrosis in one case and a septic humeral pseudoarthrosis in one case. We used one stage procedures in 38 cases (14 hips, 23 knees, 1 shoulder) and 20 two stages surgeries (16 knees and 4 hips). Additional technics used with massive prostheses, all for TKA PJis: 4 massive extensor systemallografts performed two times in a one stage procedure, two local flaps (medial gastronecmienmuscle). Two perioperative hyperbaric procedures used to limit the risks of wound complications. Results. The average follow-up is 38 months (12–62 months). The rate of sucess to treat the infection at this follow-up is 89,7 %. We report our feedback of the different massive components uses and the qualities/defaults we noted. The most frequent complication was skin events like wound swelling and delayed cicatrisations in 13 cases. 3 cases of one stages needed a complementary debridement in the three weeks after the surgery with always a good local and infectious evolution. This series report 5 failures of two stages TKA revisions. In 4 cases, the initial local soft tissues conditions were compromised. Conclusions. The use of massive prostheses to treat PJIs is a good option for the complex cases. It can be a good alternative of knee arthrodesis. These components must be used, preferentially for oldest patients, in cases of extreme bone loss or extensed osteitis to secure the bone debridement and the quality of the reconstruction. In our series, the one stage procedure is a validated option even by using complementary technics as bone allografts, extensor system allografts or flaps. The two stages procedure is a secondary option, particularly when softtissues status is compromised before or after the debridement, and mostly for the knees

Background. Impaction bone grafting (IBG) using a circumferential metal mesh is one of the options that allow restoration of the femoral bone stock and stability of the implant in hip arthroplasty. Here we examined the clinical and radiographic outcome of this procedure with a cemented stem and analyzed experimentally the initial stability of mesh–grafted bone–cemented stem complexes. Methods. We retrospectively reviewed 6 hips (6 patients) that had undergone femoral revisions with a circumferential metal mesh, impacted bone allografts, and a cemented stem. The mean follow-up period was 2.9 years (range, 1.4–3.8 years). Hip joint function was evaluated with the Japanese Orthopaedic Association hip score, and radiographic changes were determined from radiographs. The initial resistance of cemented stem complexes to axial and rotational force was measured in a composite bone model with various segmental losses of the proximal femur. Results. The hip score improved from 50 (range, 10–84) preoperatively to a mean of 74 (range, 67–88) at the final follow-up. The overall implant survival rate was 100% at 4 years when radiological loosening or revision for any reason was used as the endpoint. No stem subsided more than 3 mm vertically within 1 year after implantation. Computed tomography showed reconstitution of the femoral canal in a metal mesh. In mechanical analyses, there was no influence on the stem stability to axial compression during the repeated axial compression test between IBG reconstruction rates. On the other hand, for IBG reconstruction rate of 66.7%, grafted bone-Sawbone juntion was buckled under the axial breaking force. In contrast, under rotational load, the rotation angles of the stainless mesh were strongly affected by the IBG reconstruction rate. Conclusions. The short-term results show good outcomes for reconstruction of proximal bone loss with impaction bone allografts and a circumferential mesh. The procedure should be applied in cases where the circumferential proximal bone loss is less than half of the stem length implanted

Primary malignant bone tumor often requires a surgical treatment to remove the tumor and sometimes restore the anatomy using a frozen allograft. During the removal, there is a need for a highest possible accuracy to obtain a wide safe margin from the bone tumour. In case of reconstruction using a bone allograft, an intimate and precise contact at each host-graft junction must be obtained (Enneking 2001). The conventional freehand technique does not guarantee a wide safe margin nor a satisfying reconstruction (Cartiaux 2008). The emergence of navigation systems has procured a significant improvement in accuracy (Cartiaux 2010). However, their use implies some constraints that overcome their benefits, specifically for long bones. Patient-specific cutting guides become now available for a clinical use and drastically simplify the intra-operative set-up. We present the use of pre-operative assistances to produce patient-specific cutting guides for tumor resection and allograft adjustment. We also report their use in the operative room. We have developed technical tools to assist the surgeon during both pre-operative planning and surgery. First, the tumor extension is delineated on MRI images. These MRI images are then merged with Computed Tomography scans of the patient. The tumor and the CTscan are loaded in custom software that enables the surgeon to define target (desired) cutting planes around the tumor (Paul 2009) including a user-defined safe margin. Finally, cutting guides are designed on the virtual model of the patient as a mould of the bone surface surrounding the tumor, materialising the desired cutting planes. When required, a massive bone allograft is selected by comparing shapes of the considered patient's bone and available allografts. The resection planes are transferred onto the selected allograft and a second guide is designed for the allograft cutting. The virtually-designed cutting guides are then manufactured by a rapid prototyping machine using biocompatible material. This procedure has been used to excise a local recurrence of a tibial sarcoma and reconstruct the anatomy using a frozen tibial allograft. The pre-operative planning using virtual models of the patient's bone, tumor and the available allografts enabled the surgeon to localise the tumor, define the desired cutting planes and select the optimal allograft. Patient- and allograft-specific guides have been designed and manufactured. A stable and accurate positioning of guide onto the patient's tibia was made easier thanks to the plate formerly put in place during the previous surgery. An accurate positioning of the allograft cutting guide has been obtained thanks to its design. The obtained reconstruction was optimal with a adjusted allograft that was perfectly fitting the bone defect. The leg alignment was also optimally restored. Computer assistances for tumor surgery are progressively appearing. We have presented at CAOS 2010 an optical navigation system for tumor resection in the pelvis that was promising. However, such a tool is not well adapted for long bones. We have used patient-specific guides on a clinical case to assess the feasibility of the technique and check its accuracy in the resection and reconstruction. The surgeon has benefited from the 3D planning to define his strategy. He had the opportunity to select the optimal transplant for his patient and plan the same cuttings for the allograft and the patient. During the surgery, guide positioning was straightforward and accurate. The bone cuttings were very easy to perform. The use of custom guides decreases the operating time when compared to the conventional procedure since there is no need for measurements between cutting trajectories and anatomical landmarks. Furthermore, the same cutting planes were performed around the tumor and onto the allograft to obtain a transplant that optimally fills the defect. We recommend the use of such an intra-operative assistance for tumor surgery

Background. Despite promising results have shown by osteogenic cell-based demineralized bone matrix composites, they need to be optimized for grafts that act as structural frameworks in load-bearing defects. The purpose of this experiment is to determine the effect of bone marrow mesenchymal stem cells seeding on partially demineralized laser-perforated structural allografts that have been implanted in critical femoral defects. Materials and Methods. Thirty-two wistar rats were divided into four groups according to the type of structural bone allograft; the first: partially demineralized only (Donly), the second: partially demineralized stem cell seeded (DST), the third: partially demineralized laser-perforated (DLP), and the fourth: partially demineralized laser-perforated and stem cell seeded (DLPST). Trans-cortical holes were achieved in four rows of three holes approximated cylindrical holes 0.5 mm in diameter, with centres 2.5 mm apart. P3 MSCs were used for graft seeding. Histologic and histomorphometric analysis were performed at 12 weeks. Results. DLP grafts had the highest woven bone formation, where most parts of laser pores were completely healed by woven bone. DST and DLPST grafts surfaces had extra vessel-ingrowth-like porosities. Furthermore, in the DLPST grafts, a distinct bone formation at the interfaces was noted. Conclusion. This study indicated that surface changes induced by laser perforation, accelerated angiogenesis induction by MSCs, which resulted in endochondral bone formation at the interface. Despite non-optimal results, stem cells showed a tendency to improve osteochondrogenesis, and the process might have improved, if they could have been supplemented with the proper stipulations

Fresh-frozen allograft bone is frequently used in orthopaedic surgery. We investigated the incidence of allograft-related infection and analysed the outcomes of recipients of bacterial culture-positive allografts from our single-institute bone bank during bone transplantation. The fresh-frozen allografts were harvested in a strict sterile environment during total joint arthroplasty surgery and immediately stored in a freezer at −78° to −68° C after packing. Between January 2007 and December 2012, 2024 patients received 2083 allografts with a minimum of 12 months of follow-up. The overall allograft-associated infection rate was 1.2% (24/2024). Swab cultures of 2083 allografts taken before implantation revealed 21 (1.0%) positive findings. The 21 recipients were given various antibiotics at the individual orthopaedic surgeon's discretion. At the latest follow-up, none of these 21 recipients displayed clinical signs of infection following treatment. Based on these findings, we conclude that an incidental positive culture finding for allografts does not correlate with subsequent surgical site infection. Additional prolonged post-operative antibiotic therapy may not be necessary for recipients of fresh-frozen bone allograft with positive culture findings. Chang Gung Medical Foundation

Aim. To prevent infections after orthopaedic surgery, intravenous antibiotics are administered perioperatively. Cefazolin is widely used as the prophylactic antibiotic of choice. Systemic antibiotic therapy may however be less effective in longstanding surgery where bone allografts are used. Bone chips have been shown to be an effective carrier for certain types of antibiotics and may provide the necessary local antibiotic levels for prophylaxis. To be efficient a prolonged release is required. In contrast to vancomycin with proven efficient prolonged release from Osteomycin, this has not been described for cefazolin. We developed a protocol to bind cefazolin to bone chips by means of a hydrogel composed of proteins naturally present in the human body. Method. Three types of bone chips were evaluated: fresh frozen, decellularized frozen and decellularized lyophilized. Bone chips were incubated with 20 mg/ml cefazolin or treated with liquid hydrogel containing either 1 mg/ml fibrin or 1 mg/ml collagen and 20 mg/ml cefazolin. The cefazolin hydrogel was distributed in the porous structure by short vacuum treatment. Bone chips with cefazolin but without hydrogel were either incubated for 20 min- 4h or also treated with vacuum. Cefazolin elution of bone chips was carried out in fetal bovine serum and analysed by Ultra Performance Liquid Chromatography – Diode Array Detection. Results. Soaking of bone chips without hydrogel resulted in a quick release of cefazolin, which was limited to 4 hours. When vacuum was applied elution of >1 µg/ml cefazolin was measured for up to 36 hours. Combination with collagen hydrogel resulted in a higher cefazolin concentration released at 24 hours (3.9 vs 0.3 µg/ml), but not in a prolonged release. However, combination of decellularized frozen bone chips with fibrin hydrogel resulted in an initial release of 533 µg/ml followed by a gradual decline reaching the minimal inhibitory concentration for S. aureus at 72 hours (1.7 µg/ml), while not measurable anymore after 92 hours. Conclusions. Processed bone chips with hydrogel-cefazolin showed a markedly prolonged cefazolin release. When combined with a fibrin hydrogel, high initial peak levels of cefazolin were obtained, followed by a decreasing release over the following three days. This elution profile seems desirable, with high initial levels to maximize anti-bacterial action and low levels for a limited time to stimulate osteogenesis. Further preclinical studies are warranted to show effectiveness of hydrogel-cefazolin impregnated bone chips

Purpose. The aim of this study was to compare the clinical outcomes of the revision TKA in which trabecular metal cones and femoral head allografts were used for large bone defect. Method. Total 53 patients who have undergone revision TKA from July 2013 to March 2017 were enrolled in this study. Among them, 24 patients used trabecular metal cones, and 29 patients used femoral head allografts for large bone defect. There were 3 males and 21 females in the metal cone group, while there were 4 males and 25 females in the allograft group. The mean age was 70.2 years (range, 51–80) in the femoral head allograft group, while it was 79.1 years (range, 73–85) in the metal cone group. Bone defect is classified according to the AORI classification and clinical outcomes were evaluated with Visual Analogue Scale (VAS), Hospital Special Surgery-score (HSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), and ROM. Operation time was also evaluated. We used radiographs to check complications such as migration or loosening. We took follow-up x-rays and 3D CT of the patients, to assess the mean bone union period. Shapiro-Wilk test was done to check normality and Student T-test and Mann Whitney U-test were done for comparison between two groups. Result. The mean follow-up period was 3 .75 years (Range; 2.1 ∼ 5.75). The pre-op scores did not show significant difference. The mean VAS in the allograft and trabecular metal cone groups was 2.1 ± 0.87 and 1.8 ± 0.53, respectively (p = 0.16). The mean HSS score were 76.3 ± 5.51 and 79.2 ± 4.12 respectively (p = 0.13) and the mean WOMAC scores were 15.1 ± 3.25 and 14.8 ± 3.31 respectively (p = 0.06), and the mean KOOS scores were 27.8 ± 4.77 and 25.5 ± 4.84, respectively (p = 0.07). The mean ROM ranges were 100.6 ± 17.54 and 101.3 ± 19.22, respectively (p = 0.09). But the mean operation time of the allograft and trabecular metal cone groups was 137 minutes (Range; 111–198) and 102minutes (Range; 93 −133) (p=0.02) respectively, which showed statistical significance. In follow-up x-rays, no migration or loosening of the implants, osteolysis and other complications were found in both groups. In follow-up 3D CT, osteointegration was seen at the trabecular metal cone site, host bone being interpreted to the host bone. The allograft group showed fibrous and stable union in follow-up 3D CT. Conclusion. According to this study, in case of revision TKA with large bone defect, using whether allograft or trabecular metal cones did not affect the clinical outcomes. However, operation time was significantly shorter in trabecular metal cone group, therefore, in patients with poor general condition along with severe underlying diseases, usage of trabecular metal cone would be a better choice to shorten operation time and ease postoperative care. Keywords. Revision TKA, metal cone, allograft, bone defect. For any figures or tables, please contact authors directly

Aims. 1. A two-stage revision remains as the “gold standard” treatment for chronically infected total knee arthroplaties. 2. Evaluate technical challenges in two stage revision. Materials and Methods. Fourteen septic knee prostheses were revised with a minimum follow-up of 2 years. Static antibiotic-impregnated cement spacers were used in all cases. Intravenous antibiotics according to sensitivity test of the culture were applied during patients’ hospital stay and continued up to 3 weeks. Oral antibiotics were given for another 3 weeks. Second-stage surgery was undertaken after control of infection with normal erythrocyte sedimentation rate and C-reactive protein values. Extensile techniques were used if needed and metallic augments were employed for bone loss in revision of both femur and tibia components. Results. The average interval between the first-stage resection and reimplantation was 7 weeks. Significant improvement was obtained with respect to visual analog scale pain and clinical and functional scores, and infection was not seen in all cases following a two-stage revision total knee arthroplasty. Radiographic evaluation showed suitable alignment without signs of mechanical loosening. Average range of movement achieved was 0 to 100 degrees. Most common knee infected was the second knee in bilateral cases. Conclusions. This technique is a reasonable procedure in chronic infection in knee arthroplasty and provides proper functional and clinical results. However, it sometimes requires extensile surgical approaches that could imply arduous surgeries. Metallic augments with cement less stems available in most of the knee revision systems are a suitable alternative to handle bone deficiencies, avoiding the use of bone allograft with its complications

Infected nonunion of the femur or tibia diaphysis requires resection of infected bone, stabilization of bone and reconstruction of bone defect. External fixation of the femur is poorly tolerated by patients. In 2004 authors introduced in therapy for infected nonunions of tibia and femur diaphysis coating of IMN with a layer of antibiotic loaded acrylic cement (ALAC) containing 5% of culture specific antibiotic. Seven patients with infected nonunion of the diaphysis of femur (2) and tibia (2) were treated, aged 20–63 years, followed for 2–9 years (average 5,5 years). All have been infected with S. aureus (MSSA: 2 and MRSA: 4) or Staph. epidermidis (1) and in one case with MRSA and Pseudomonas aeruginosa. All patients underwent 3 to 6 operations before authors IMN application. Custom-made IMN coated with acrylic cement (Palamed) loaded fabrically with gentamycin with admixture of 5% of culture-specific antibiotic: vancomycin (7 cases) and meropeneme (1 case) was used for bone stabilization. Static interlocking of IMN was applied in 4 cases and dynamic in 2 cases. In 1 case the femur was stabilized with IMN without interlocking screws. In 2 cases IMN was used for fixation of nonunion at docking site after bone transport. In 3 cases ALAC was used as temporary defect filling and dead space management. In one case after removal of IMN coated with ALAC, a new custom made Gamma nail and tubular bone allograft ranging 11 cm was used for defect reconstruction. Infection healing was achieved in all 7 cases, bone union was achieved in 4 from 7 cases. In 1 case of segmental diaphyseal defect ranging over 12 cm infection was healed, but bone defect was not reconstructed. This patient is waiting for total femoral replacement. In another case of segmental defect of 11 cm infection is healed, but allograft substitution and remodeling by host bone is poor. In the 3rd case of lacking bone healing, the 63 year old patients was noncooperative and not willing to walk in walker with weight bearing. This patient refused further treatment. Custom-made intramedullary nail coated with a layer of acrylic cement loaded with 5% of culture specific antibiotic can provide local infection control, offer comfortable bone stabilization, and replace standard IM nail in therapy for difficult to treat infected diaphyseal nonunion of femur or tibia

To evaluate the value of the use of massive prostheses in periprosthetic infections both in one stage and two stages procedures. Between 2008 and 2014, 236 revisions for PJI had been performed in our hospital by the same surgeon. For the most complex cases, we decided to introduce megaprostheses in our practice in 2011. We report a prospective series of 33 infected patients treated between 2011 and the end of 2014, 14 male and 19 female with on average 67.9 years old (38–85) Infection involved TKA in 22 cases (17 TKA revisions, 4 primary TKA), THA in 9 cases (6 revisions, 3 primary THA), a femoral pseudo-arthrosis with posttraumatic gonarthrosis in one case and a septic humeral pseudoarthrosis in one case. We used a total femoral component for two patients: the first one for a hip PJI with extended diaphyseal bone loss and multiples sinus tracks, and the second one for a massive infected knee prosthesis used in a knee reconstruction for liposarcoma. We used one stage procedures in 20 cases (8 hips, 12 knees, 1 shoulder) and two stages in 13 cases (12 knees and 1 hip). Additional technics included 3 massive extensor system allografts, two local flaps. Perioperative hyperbaric treatment was used for 2 patients. The average follow up is 19.8 months (6–48 months). The most frequent complications were wound swelling and delayed healing in 8 cases;). In 3 cases of one stage surgery a complementary debridement was necessary in the three weeks after the surgery with always a good local and infectious evolution. VAC therapy was used in four cases with good results. We report one early postoperative dead. In summary, the use of massive prostheses in PJI is a good option for complex cases. It can be a good alternative to knee arthrodesis. These components must be used preferentially for older patients, in cases of extreme bone loss or extensive osteomyelitis to secure the bone debridement and the quality of the reconstruction. In our series, the one stage procedure is a validated option even by using complementary technics as bone allografts, extensor system allografts or flaps. We believe the two stages surgery is a secondary option, particularly when soft tissues status is compromised before or after the debridement, and mostly for the knees. The longevity of the implantation must be evaluate by a long term follow up

Introduction. Acetabular reconstruction of a total hip arthroplasty (THA) for a case with severe bone loss is most challenging for surgeon. Relatively high rate of failure after the reconstruction surgery have been reported. We have used Kerboull-type acetabular reinforcement devices with morsellised or bulk bone allografts for these cases. The purpose of this study was to examine the midterm results of revision THA using Kerboull-type acetabular reinforcement devices. Patients and methods. We retrospectively reviewed 20 hips of revision THA (20 patients) between February 2002 and August 2010. The mean age of the patients at the time of surgery was 67.4 years (range 45–78). All of the cases were female. The mean duration of follow-up was 6.5 years (range 2.1–10.4). The reasons of revision surgeries were aseptic loosening in 10 hips, migration of bipolar hemiarthroplasty in 8 hips, and rheumatoid arthritis in 2 hips. We classified acetabular bone defects according to the American Academy of Orthopaedic Surgeons (AAOS) classification; we found two cases of Type II and eighteen cases of Type III. In terms of bone graft, we performed both bulk and morsellised bone grafts in 6 hips and morsellised bone grafts only in 14 hips. We assessed cup alignment using postoperative computed tomography (CT) and The post-operative and final follow-up radiographs were compared to assess migration of the implant. We measured the following three parameters: the angle of inclination of the acetabular device (Fig. 1); the horizontal migration (Fig. 2a); and vertical migration (Fig. 2b). Substantial migration was defined as a change in the angle of inclination of more than 3 degrees or migration of more than 3 mm. The pre- and postoperative hip functions were evaluated using the Japanese Orthopaedic Association (JOA) hip score. Results. The mean cup inclination and anteversion were 38.4 degrees and 10.6 degrees, respectively. The mean change in the angle was 1.9 degrees in inclination of the device. The average horizontal migration was 1.0 mm, and the vertical migration was 2.0 mm. Only one hip showed substantial migration with breakage of the device. This failure case represented a large amount of posterior pelvic tilt in standing position postoperatively. The mean JOA hip score was increased from 46.7 to 74.8. Discussion. Poor outcome using Kerboull-type reinforcement plate with morsellised bone graft only has been demonstrated by many reports. In these literatures, bulk bone graft was recommended particularly in the case of large bone defect such as larger than half of the rounded plate of the device or more than 2 cm of thickness. In our case series, acetabular reconstruction using a Kerboull- type acetabular reinforcement device and bone graft gives satisfactory mid-term results even with morsellized bone graft only. One possible interpretation is that most of our cases had relatively small bone defect according to the staging of severity of the superior segmental bone loss made by Kawanabe et al. We suggest that the progressive posterior pelvic tilt should be considered to be a risk of poor outcome of the acetabular reconstruction using this device. To view tables/figures, please contact authors directly

Introduction:. Two-stage revision is a widely accepted and performed intervention for septic total knee arthroplasty (TKA), with an infection eradication rate exceeding 90% in most studies. The ‘2-in-1’ single stage revision has recently been reported to have favourable results. Aim:. To evaluate the early clinical results of single-stage reimplantation of infected TKA using stepped metaphyseal femoral and tibial sleeves. Methods:. From March 2009 to January 2010, 8 patients with a diagnosis of infected total knee arthroplasty were treated with ‘2 in 1’ single-stage reimplantation in our institution. There were 4 men and 4 women with an average age of 71 years. The revision operation was performed in patients presenting with an infected TKA and who had mild to moderate tibial or femoral bone loss. We used extraction of implants, debridement and lavage in the first stage and re-draped patients prior to the second stage which included the definitive implantation. All the patients received intravenous antibiotics for two weeks and oral antibiotics were continued for further 6–12 weeks until the serum CRP & WBC were normal. None of these patients required intra operative bone allografting. Results:. Clinical evaluation at the last follow up showed significant improvement in the knee pain and stiffness score. Radiological evaluation was done using the Knee Society system. None of the knees showed evidence of infection or loosening at the mean follow up of eighteen months. Conclusion:. Metaphyseal femoral and tibial sleeves may enable reconstruction of contained and uncontained bone stock, insertion of a stable implant and control of infection in a single operation in revision TKR for infection. The increased morbidity and cost of a two-stage procedure is thus avoided

The biological properties of morselised bone allograft treated with either a supercritical fluid process or low-dose (15 kGy) gamma irradiation were compared using radiological, histological and immunohistological techniques. The aims were to investigate any differences in the biological properties of supercritical fluid treated allograft and low-dose gamma irradiated allograft in-vivo. Rabbit allograft were cleaned of all soft tissue, cartilage and processed into ‘corticancellous crunch’ using a Noviomagus Bone Mill. Pooled samples were either gamma irradiated (15 kGy) or treated by NovaSterilis using super critical carbon dioxide. A well-reported tibial defect model in ten rabbits was used to examine the in vivo response of the different treatments at two and four weeks following surgery (n=5 per time point). Radiographic (x-ray, CT and micro CT), histology and immunohistochemistry was used to assess the in vivo response. Radiographic results revealed an initial response to the gamma-irradiated samples compared to SCF. Histology confirmed this reaction to be inflammatory in nature at two weeks that continued at four weeks for the gamma irradiated samples. In contrast, the SCF treated sample demonstrated new bone formation while the inflammatory reaction was muted compared to the gamma irradiated samples. Four week x-rays and histology confirmed new bone formation in both groups while the lack of significant inflammatory response in the SCF group was noted. Allograft sterilisation techniques do not result in the same initial response when evaluated in vivo. Removal of lipids and cellular debris following SCF treatment may influence the in vivo response. While both techniques can provide a sterile product, the in vivo response requires further investigation