Objectives. Distraction osteogenesis (DO) mobilises bone regenerative potential and avoids the complications of other treatments such as bone graft. The major disadvantage of DO is the length of time required for bone consolidation. Mesenchymal stem cells (MSCs) have been used to promote bone formation with some good results. Methods. We hereby review the published literature on the use of MSCs in promoting bone consolidation during DO. Results. Studies differed in animal type (mice, rabbit, dog, sheep), bone type (femur, tibia, skull), DO protocols and cell transplantation methods. Conclusion. The majority of studies reported that the transplantation of MSCs enhanced bone consolidation or formation in DO. Many questions relating to animal model, DO protocol and cell transplantation regime remain to be further investigated. Clinical trials are needed to test and confirm these findings from animal studies. Cite this article: Y. Yang, S. Lin, B. Wang, W. Gu, G. Li. Stem cell therapy for enhancement of bone consolidation in distraction osteogenesis: A contemporary review of experimental studies. Bone Joint Res 2017;6:385–390. DOI: 10.1302/2046-3758.66.BJR-2017-0023

Aims. Distraction osteogenesis (DO) is a useful orthopaedic procedure employed to lengthen and reshape bones by stimulating bone formation through controlled slow stretching force. Despite its promising applications, difficulties are still encountered. Our previous study demonstrated that pulsed electromagnetic field (PEMF) treatment significantly enhances bone mineralization and neovascularization, suggesting its potential application. The current study compared a new, high slew rate (HSR) PEMF signal, with different treatment durations, with the standard Food and Drug Administration (FDA)-approved signal, to determine if HSR PEMF is a better alternative for bone formation augmentation. Methods. The effects of a HSR PEMF signal with three daily treatment durations (0.5, one, and three hours/day) were investigated in an established rat DO model with comparison of an FDA-approved classic signal (three hrs/day). PEMF treatments were applied to the rats daily for 35 days, starting from the distraction phase until termination. Radiography, micro-CT (μCT), biomechanical tests, and histological examinations were employed to evaluate the quality of bone formation. Results. All rats tolerated the treatment well and no obvious adverse effects were found. By comparison, the HSR signal (three hrs/day) treatment group achieved the best healing outcome, in that endochondral ossification and bone consolidation were enhanced. In addition, HSR signal treatment (one one hr/day) had similar effects to treatment using the classic signal (three three hrs/day), indicating that treatment duration could be significantly shortened with the HSR signal. Conclusion. HSR signal may significantly enhance bone formation and shorten daily treatment duration in DO, making it a potential candidate for a new clinical protocol for patients undergoing DO treatments. Cite this article: Bone Joint Res 2021;10(12):767–779

Aims. This study aims to enhance understanding of clinical and radiological consequences and involved mechanisms that led to corrosion of the Precice Stryde (Stryde) intramedullary lengthening nail in the post market surveillance era of the device. Between 2018 and 2021 more than 2,000 Stryde nails have been implanted worldwide. However, the outcome of treatment with the Stryde system is insufficiently reported. Methods. This is a retrospective single-centre study analyzing outcome of 57 consecutive lengthening procedures performed with the Stryde nail at the authors’ institution from February 2019 until November 2020. Macro- and microscopic metallographic analysis of four retrieved nails was conducted. To investigate observed corrosion at telescoping junction, scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX) were performed. Results. Adjacent to the nail’s telescoping junction, osteolytic changes were observed in bi-planar radiographs of 20/57 segments (35%) after a mean of 9.5 months (95% confidence interval 7.2 to 11.9) after surgery. A total of 8/20 patients with osseous alterations (40%) reported rest and ambulation pain of the lengthened segment during consolidation. So far, 24 Stryde nails were retrieved and in 20 (83%) macroscopic corrosion was observed at the nail’s telescoping junction. Before implant removal 11/20 radiographs (55%) of lengthened segments with these 20 nails revealed osteolysis. Implant retrieval analysis by means of SEM showed pitting and crevice corrosion. EDX detected chromium as the main metallic element of corrosion. Conclusion. Patients are exposed to the risk of implant-related osteolysis of unclear short- and long-term clinical consequences. The authors advocate in favour of an early implant removal after osseous consolidation. Cite this article: Bone Joint Res 2021;10(7):425–436

Introduction. Bone transport and distraction osteogenesis have been shown to be an effective treatment for significant bone loss in the tibia. However, traditional methods of transport are often associated with high patient morbidity due to the pain and scarring caused by the external frame components transporting the bone segment. Prolonged time in frame is also common as large sections of regenerate need significant time to consolidate before the external fixator can be removed. Cable transport has had a resurgence with the description of the balanced cable transport system. However, this introduced increasingly complex surgery along with the risk of cable weave fracture. This method also requires frame removal and intramedullary nailing, with a modified nail, to be performed in a single sitting, which raised concern regarding potential deep infection. An alternative to this method is our modified cable transport system with early intramedullary nail fixation. Internal cables reduce pain and scarring of the skin during transport and allow for well controlled transport segment alignment. The cable system is facilitated through an endosteal plate that reduces complications and removes the need for a single-stage frame removal and nailing procedure. Instead, the patients can undergo a pin-site holiday before nailing is performed using a standard tibial nail. Early intramedullary nailing once transport is complete reduces overall time in frame and allows full weight bearing as the regenerate consolidates. We present our case series of patients treated with this modified cable transport technique. Methodolgy. Patients were identified through our limb reconstruction database and clinic notes, operative records and radiographs were reviewed. Since 2019, 8 patients (5 male : 3 female) have undergone bone transport via our modified balanced cable transport technique. Average age at time of transport was 39.6 years (range 21–58 years) with all surgeries performed by the senior author. Patients were followed up until radiological union. We recorded the length of bone transport achieved as well as any problems, obstacles or complications encountered during treatment. We evaluated outcomes of full weight bearing and return to function as well as radiological union. Results. 4/8 bone defects were due to severely comminuted open fractures requiring extensive debridement. All other cases had previously undergone fixation of tibial fractures which had failed due to infection, soft tissue defects or mal-reduction. The mean tibial defect treated with bone transport was 41mm (range 37–78mm). From the start of cable transport to removal of external fixator our patients spent an average of 201 days in frame. 7/8 patients underwent a 2-week pin-site holiday and subsequent insertion of intramedullary nail 2 weeks later. One patient had sufficient bony union to not require further internal fixation after frame removal. 10 problems were identified during treatment. These included 4 superficial infections treated with antibiotics alone and 5 issues with hardware, which could be resolved in the outpatient clinic. 1 patient had their rate of transport slowed due to poor skin quality over the site of the regenerate. 4 obstacles resulted in a return to theatre for additional procedures. 1 patient had a re-do corticotomy and 3 had revision of their internal cable transport constructs due to decoupling or screw pull out. 1 patient had residual ankle joint equinus following treatment which required an Achilles tendon lengthening procedure. Another patient underwent treatment for DVT. There were no deep infections identified and no significant limb length discrepancies or deformities. Conclusions. Overall, we have found that our modified balanced cable transport technique has allowed for successful bone transport for significant defects of the tibia. We have learned from the obstacles encountered during this case series to avoid unnecessary return trips to theatre for our future transport patients. The internal cable system allowed all patients to complete their planned transport without excessive pin tract scarring or pain. Early conversion to intramedullary nail allowed for a shorter time in frame with continued full weight bearing as the regenerate consolidated. No metalwork failure or deformity has occurred in relation to docking site union. All patients have made a good return to pre-operative function during their follow-up period with no evidence of late complications such as deep infection

Introduction. This study aims to evaluate the effect of using different types of fixator on the quality of callus and complications during distraction osteogenesis in patients with achondroplasia. Materials and Methods. Forty-nine achondroplasia patients with a minimum follow-up of 36 months who underwent limb lengthening between 2005 and 2017 with external fixator only were included. Thirty-three of the patients underwent lengthening using classical Ilizarov frame, while spatial frame used for sixteen. Regenerate quality is evaluated according to the Li classification on the X-ray taken one month after the end of the distraction. Complications were noted in the follow-up period. Results. The mean age at the time of surgery was 8,6 years. The mean external fixation index (EFI) was 34,3 and 30,1 day/cm for spatial frame and Ilizarov frame respectively. Mean follow-up period of 161,62 months and mean fixator period of 257 days. Amount of lengthening was 7,2 cm for Ilizarov frame, and 7,5 cm for spatial frame. Rate of callus with good morphological quality seen at consolidation was 72,4% and 50% for Ilizarov and spatial frames respectively. Two groups show similar results of complication rates in terms of pin site infection, premature fibular consolidation, regenerate fracture, plastic deformation, knee contracture. However fibular nonunion rates were higher for Ilizarov-type fixator. Conclusions. Although spatial frame with computer assistance brings easier follow-up for deformity correction, Ilizarov-type external fixator show slightly higher rates of good quality callus during consolidation for patients with achondroplasia

Introduction. The reconstruction of segmental long bone defects remains one of the holy grails of orthopaedic surgery. The optimal treatment of which remains a topic of great debate. This study aimed to evaluate the outcomes following the management of critical-sized bone defects using a classification-based treatment algorithm. Materials & Methods. A retrospective review of all patients undergoing treatment for segmental diaphyseal defects of long bones at a tertiary-level limb reconstruction unit was performed. The management of the bone defect was standardised as per the classification by Ferreira and Tanwar (2020). Results. A total of 96 patients (mean age 39.8, SD 15.2) with a minimum six months follow-up were included. Most bone defects were the result of open fractures (75/96) with 67% associated with Gustilo-Anderson IIIB injuries. There was a statistical difference in the likelihood of union between treatment strategies with more than 90% of cases undergoing acute shortening and bone transport achieving union and only 72% of cases undergoing the induced membrane technique consolidating (p=0.049). Of those defects that consolidated, there was no difference in the time to bone union between strategies (p=0.308) with an overall median time to union 8.33 months (95% CI 7.4 — 9.2 months). The induced membrane technique was associated with a 40% risk of sepsis. Conclusions. This study reported the outcomes of a standardised approach to the management of critical-sized bone defects. Whilst overall results were supportive of this approach, the outcomes associated with the induced membrane technique require further refinement of its indications in the management of critical-sized bone defects

Aim. Fracture-related infection (FRI) is a severe post-traumatic complication which can be accompanied with a soft-tissue defect or an avital soft-tissue envelope. In these cases, a thoroughly planned orthoplastic approach is imperative since a vital soft-tissue envelope is mandatory to achieve fracture union and infection eradication. The aim of our study was to analyse plastic surgical aspects in the management of FRIs, including the type and outcome of soft-tissue reconstruction (STR), and to investigate the long-term outcome of FRI after STR. Method. Patients with a lower leg FRI requiring STR that were treated from 2010 to 2018 at our center were included in this retrospective analysis. STR involved the use of local, pedicled and free flaps. The primary outcome was the success rate of STR, and the secondary outcome was long-term fracture consolidation and cure of infection. Results. Overall, 145 patients with lower leg FRI were identified, of whom 58 (40%) received STR. Muscle flaps were applied in 38, fascio-cutaneous flaps in 19 and a composite osteo-cutaneous flap in one case. All patients underwent successful STR (primary STR in 51/58 patients, 7/58 patients needed secondary STR). A high Charlson Comorbidity Index Score was a significant risk factor for flap failure (p=0.011). Patients with free-flap STR developed significantly more severe complications and needed more surgical interventions (Clavien-Dindo ≥IIIa; p=0.001). Out of the 43 patients that completed long-term follow-up (mean 24 months), fracture consolidation was achieved in 32 and infection eradication in 31. Polymicrobial infection was a significant risk factor for fracture non-union (p=0.002). American Society of Anesthesiologists (ASA) classification of 3 or higher (p=0.040) was a risk factor for persistence or recurrence of infection. Conclusions. In our population, 58/145 patients with FRI required STR. STR was successful in all patients eventually, in 7/58 patients secondary STR was necessary. Therefore, STR should be sought even if primary STR fails. Despite successful STR, the long-term composite outcome showed a high rate of failed fracture consolidation and failed eradication of infection, which was independent of primary STR failure

Introduction. The purpose of this research is to compare the quality of life in children during gradual deformity correction using external fixators with intramedullary lengthening nails. Materials and Methods. Prospective analysis of children during lower limb lengthening. Group A included children who had external fixation, patients in group B had lengthening nails. Patients in each group were followed up during their limb reconstruction. CHU-9D and EQ-5DY instruments were used to measure quality of life at fixed intervals. The first assessment was during the distraction phase (1 month postop.), the second was during the early consolidation phase (3 months postop.) and the final one was late consolidation phase (6–9 months depends on the frame time). Results. Group B patients reported significantly better utility compared to Group A. This was observed during all the stages of the treatment. Group B children were less worried (P 0.004), less sad (P 0.0001), less pain (p <0.0001), less tired (P 0.0002), better school work (P0.0041), better sleep (p 0.016), more able to do sports activities (p 0.004) and, they were more independent (p <0.0001) compared to group B. QALYS was better for the nails group compared to external fixation group 0.44 compared to 0.36 for external fixators. Conclusions. Lengthening nails had the potential to improve the quality of life and utility compared to external fixation. This will help further economic evaluation to measure ICER to further explore the cost effectiveness of these devices

Aims. Return to sport following undergoing total (TKA) and unicompartmental knee arthroplasty (UKA) has been researched with meta-analyses and systematic reviews of varying quality. The aim of this study is to create an umbrella review to consolidate the data into consensus guidelines for returning to sports following TKA and UKA. Methods. Systematic reviews and meta-analyses written between 2010 and 2020 were systematically searched. Studies were independently screened by two reviewers and methodology quality was assessed. Variables for analysis included objective classification of which sports are safe to participate in postoperatively, time to return to sport, prognostic indicators of returning, and reasons patients do not. Results. A total of 410 articles were found, including 58 duplicates. Seven articles meeting inclusion criteria reported that 34% to 100% of patients who underwent TKA or UKA were able to return to sports at 13 weeks and 12 weeks respectively, with UKA patients more likely to do so. Prior experience with the sport was the most significant prognostic indicator for return. These patients were likely to participate in low-impact sports, particularly walking, cycling, golf, and swimming. Moderate-impact sport participation, such as doubles tennis and skiing, may be considered on a case-by-case basis considering the patient’s prior experience. There is insufficient long-term data on the risks to return to high-impact sport, such as decreased implant survivorship. Conclusion. There is a consensus that patients can return to low-impact sports following TKA or UKA. Return to moderate-impact sport was dependent on a case-by-case basis, with emphasis on the patient’s prior experience in the sport. Return to high-impact sports was not supported. Patients undergoing UKA return to sport one week sooner and with more success than TKA. Future studies are needed to assess long-term outcomes following return to high-impact sports to establish evidence-based recommendations. This review summarizes all available data for the most up-to-date and evidence-based guidelines for returning to sport following TKA and UKA to replace guidelines based on subjective physician survey data. Cite this article: Bone Jt Open 2022;3(3):245–251

Aims. The aim of this study was to inform the epidemiology and treatment of slipped capital femoral epiphysis (SCFE). Methods. This was an anonymized comprehensive cohort study, with a nested consented cohort, following the the Idea, Development, Exploration, Assessment, Long-term study (IDEAL) framework. A total of 143 of 144 hospitals treating SCFE in Great Britain participated over an 18-month period. Patients were cross-checked against national administrative data and potential missing patients were identified. Clinician-reported outcomes were collected until two years. Patient-reported outcome measures (PROMs) were collected for a subset of participants. Results. A total of 486 children (513 hips) were newly affected, with a median of two patients (interquartile range 0 to 4) per hospital. The annual incidence was 3.34 (95% confidence interval (CI) 3.01 to 3.67) per 100,000 six- to 18-year-olds. Time to diagnosis in stable disease was increased in severe deformity. There was considerable variation in surgical strategy among those unable to walk at diagnosis (66 urgent surgery vs 43 surgery after interval delay), those with severe radiological deformity (34 fixation with deformity correction vs 36 without correction) and those with unaffected opposite hips (120 prophylactic fixation vs 286 no fixation). Independent risk factors for avascular necrosis (AVN) were the inability of the child to walk at presentation to hospital (adjusted odds ratio (aOR) 4.4 (95% CI 1.7 to 11.4)) and surgical technique of open reduction and internal fixation (aOR 7.5 (95% CI 2.4 to 23.2)). Overall, 33 unaffected untreated opposite hips (11.5%) were treated for SCFE by two-year follow-up. Age was the only independent risk factor for contralateral SCFE, with age under 12.5 years the optimal cut-off to define ‘at risk’. Of hips treated with prophylactic fixation, none had SCFE, though complications included femoral fracture, AVN, and revision surgery. PROMs demonstrated the marked impact on quality of life on the child because of SCFE. Conclusion. The experience of individual hospitals is limited and mechanisms to consolidate learning may enhance care. Diagnostic delays were common and radiological severity worsened with increasing time to diagnosis. There was unexplained variation in treatment, some of which exposes children to significant risks that should be evaluated through randomized controlled trials. Cite this article: Bone Joint J 2022;104-B(4):519–528

It is common belief that consolidated intramedullary nailed trochanteric femur fractures can result in secondary midshaft or supracondylar fractures, involving the distal screws, when short or long nails are used, respectively. In addition, limited data exists in the literature to indicate when short or long nails should be selected for treatment. The aim of this biomechanical cadaveric study was to investigate short versus long Trochanteric Femoral Nail Advanced (TFNA) fixation in terms of construct stability and generation of secondary fracture pattern following trochanteric fracture consolidation. Eight intact human cadaveric femur pairs were assigned to 2 groups of 8 specimens each for nailing using either short or long TFNA with blade as head element. Each specimen was first biomechanically preloaded at 1 Hz over 2000 cycles in superimposed synchronous axial compression to 1800 N and internal rotation to 11.5 Nm. Following, internal rotation to failure was applied over an arc of 90° within 1 second under 700 N axial load. Torsional stiffness, torque at failure, angle at failure and energy at failure were evaluated. Fracture patterns were analyzed. Outcomes in the groups with short and long nails were 9.7±2.4 Nm/° and 10.2±2.9 Nm/° for torsional stiffness, 119.8±37.2 Nm and 128.5±46.7 Nm for torque at failure, 13.5±3.5° and 13.4±2.6° for angle at failure, and 887.5±416.9 Nm° and 928.3±461.0 Nm° for energy at failure, respectively, with no significant differences between them, P≥0.167. Fractures through the distal locking screw occurred in 5 and 6 femora instrumented with short and long nails, respectively. Fractures through the lateral entry site of the head element were detected in 3 specimens within each group. For short nails, fractures through the distal shaft region, not interfacing with the implant, were detected in 3 specimens. From biomechanical perspective, the risk of secondary peri-implant fracture after intramedullary nailed trochanteric fracture consolidation is similar when using short or long TFNA. Moreover, for both nail versions the fracture pattern does not unexceptionally involve the distal locking screw

Renal Osteodystrophy is a type of metabolic bone disease characterized by bone mineralization deficiency due to electrolyte and endocrine abnormalities. Patients with chronic kidney disease (CKD) are more likely to experience falls and fractures due to renal osteodystrophy and the high prevalence of risk factors for falls. Treatment involves medical management to resolve the etiology of the underlying renal condition, as well as management (and prevention) of pathological fractures. A 66-year-old female patient, with severe osteoporosis and chronic kidney disease undergoing haemodialysis, has presented with multiple fractures along the years. She was submitted to bilateral proximal femoral nailing as fracture treatment on the left and prophylactically due to pathological bone injury on the right, followed by revision of the left nail with a longer one after varus angulation and fracture distal to the nail extremity. Meanwhile, the patient suffered a pathological fracture of the radial and cubital diaphysis and was submitted to conservative treatment with cast, with consolidation of the fracture. Posteriorly, she re-fractured these bones after a fall and repeated the conservative treatment. Clinical management: There is a multidisciplinary approach to manage the chronic illness of the patient, including medical management to resolve the etiology and consequences of her chronic kidney disease, pain control, conservative or surgical fracture management and prevention of falls. The incidence of chronic renal disease is increasing and the patients with this condition live longer than previously and are more physically active. Thus, patients may experience trauma as a direct result of increased physical activity in a setting of weakened pathologic bone. Their quality of life is primarily limited by musculoskeletal problems, such as bone pain, muscle weakness, growth retardation, and skeletal deformity. A multidisciplinary approach is required to treat these patients, controlling their chronic diseases, managing fractures and preventing falls

To evaluate the functional outcome of open humerus diaphyseal fractures treated with the Three-stitch technique of antegrade humerus nailing. This is a retrospective study conducted at the Department of Orthopaedics in D. Y. Patil University, School of Medicine, Navi Mumbai, India. The study included 25 patients who were operated on from January 2019 to April 2021 and follow-ups done till May 2022. Inclusion criteria were adult patients with open humerus diaphyseal fractures (Gustilo-Anderson Classification). All patients with closed fractures, skeletally immature patients, and patients with associated head injury were excluded from the study. All patients were operated on with a minimally invasive Three-stitch technique for antegrade humerus nailing. All patients were evaluated based on DASH score. Out of the 25 patients included in the study, all patients showed complete union. The mean age of the patients was 40.4 years (range 23–66 years). The average period for consolidation of fracture was 10.56 weeks (range 8–14 weeks). The DASH score ranged from 0 to 15.8 with an average score of 2.96. Five patients reported complications with three patients of post-operative infection and delayed wound healing and two patients with screw loosening. All complications were resolved with proper wound care and the complete union was noted. None of the patients had an iatrogenic neurovascular injury. Three-stitch antegrade nailing technique is a novel method to treat diaphyseal humerus fractures and provides excellent results. It has various advantages such as minimal invasiveness, minimal injury to the rotator cuff, fewer infection rates, minimal iatrogenic injuries, and good functional outcomes. Therefore, this treatment modality can be effectively used for open humerus diaphyseal fractures

Introduction. The FitBone lengthening nail (Orthofix UK) is an intramedullary device licensed for the lengthening of long bones in adults in the UK. It contains a motor powered by electricity transmitted via an induction coil placed underneath the skin. It was developed in Germany two decades ago but uptake in the UK has only started more recently. The aim of this study was to review the first cohort of FitBone lengthening nails in a unit with significant experience of other lengthening nails (including PRECICE and Stryde). Materials & Methods. Demographic, clinical and radiological data was prospectively collected on all FitBone cases starting in February 2022. Accuracy of lengthening rate, patient satisfaction and implant issues were all considered. Complications and learning points were recorded and discussed by the multidisciplinary team involved in the patients care. Results. Eleven lengthening nails were inserted between February and November 2022 (6 right femurs, 5 left femurs). The average patient age was 31 (16–57) with 4 females and 7 males. The average lengthening achieved was 44mm (13– 70) over an average of 59 days (35 to 104). Significant technical issues were encountered in this cohort of patients including slow opening up at osteotomy site (3 requiring speeding up of programme), early consolidation (one requiring re-do osteotomy) and backing out of locking screws (3 out of 11 nails). There were also patient use concerns with difficulty using the motor and the inability to reverse the lengthening without an additional component to the motor. Conclusions. We present the first UK cohort of patients with femoral lengthening using the FitBone implant and device. We highlight the technical and patient issues encountered during this learning curve and propose solutions to avoid these pitfalls

Introduction. The practice of limb lengthening using intramedullary nails has surged in popularity in recent years. Our study explores the relationship between femur lengthening and overall height gain in adults undergoing cosmetic limb lengthening with telescoping magnetic intramedullary lengthening nails (MILNs). Materials & Methods. Demographic information, pre- and postoperative radiographic data, and secondary outcomes, such as mechanical angles and sagittal alignment, were analyzed for 42 adult femurs MILNs (PRECICE 2, NuVasive, Inc.). Height was assessed with a digital stadiometer. Limb lengthening was defined as the amount of nail distraction seen on a calibrated weight bearing X-ray at consolidation. mLDFA, mMPTA, MAD, AMA, and femoral sagittal bow were evaluated as secondary outcomes. Results. Mean starting height was 163.5 cm (SD 10.4, range 137–179) Post -lengthening mean height increased to 171.1 cm (SD 10.1, range 146.7–185.3). Average height gain was 7.5 cm (SD 1.3 cm, range 5.1–9.5). Average femoral lengthening was 7.3 cm (SD 1.14, range 4.1–10.1). There were no statistically significant difference between height gain and femur lengthening. Secondary outcomes showed reductions in femoral sagittal bow and AMA. Conclusions. We conclude that measuring femur lengthening is a reliable and accurate method of measuring gained height in deformity-free patients undergoing limb lengthening. We further reason that straightening of both femoral and spinal sagittal bow counteracts potential lengthening loss over the anatomical axis, versus mechanical axis lengthening

Introduction. The presence of pluripotent mesenchymal cells in the periosteum along with the growth factors produced or released following injury provides this tissue with an important role in bone healing. Utilising this property, vascularised periosteal flaps may increase the union rates in recalcitrant atrophic long bone non-union. The novel chimeric fibula-periosteal flap utilises the periosteum raised on an independent periosteal vessel, thus allowing the periosteum to be inset freely around the osteotomy site, improving bone biology. Materials & Methods. Ten patients, with established non-union, underwent fibula-periosteal chimeric flaps (2016–2022) at the Canniesburn Plastic Surgery Unit, UK. Preoperative CT angiography was performed to identify the periosteal branches. A case-control approach was used. Patients acted as their own controls, which obviated patient specific risks for non-union. One osteotomy site was covered by the chimeric periosteal flap and one without. In two patients both the osteotomies were covered using a long periosteal flap. Results. Union rate of 100% (11/11) was noted with periosteal flap osteotomies, versus those without flaps at 28.6% (2/7) (p = 0.0025). Time to union was also reduced in the periosteal flaps at 8.5 months versus 16.75 months in the control group (p = 0.023). Survival curves with a hazard ratio of 4.1, equating to a 4 times higher chance of union with periosteal flaps (log-rank p = 0.0016) was observed. Conclusions. The chimeric fibula-periosteal flap provides an option for atrophic recalcitrant non-unions where use of vascularised fibula graft alone may not provide an adequate biological environment for consolidation

Introduction. The use of vascularised fibula grafts is an accepted method for reconstructing the distal femur following resection of malignant childhood tumours. Limitations relate to the mismatch of the cross-sectional area of the transplanted fibula graft and thel ocal bone, instability of the construct and union difficulties. We present midterm results of a unique staged technique—an immediate defect reconstruction using a double-barrel vascularised fibula graft set in in A-frame configuration and a subsequent intramedullary femoral lengthening. Materials & Methods. We retrospectively included 10 patients (mean age 10 y)with an osteosarcoma of the distal femur, who were treated ac-cording to the above-mentioned surgical technique. All patients were evaluated with regards to consolidation of the transplanted grafts, hypertrophy at the graft-host junctions, leg length discrepancies, lengthening indices, complications as well as functional outcome. Results. The mean defect size after tumour resection was 14.5 cm, the mean length of the harvested fibula graft 22 cm, resulting in a mean (acute) shortening of 4.7 cm (in 8 patients). Consolidation was achieved in all cases, 4 patients required supplementary bone grafting. Hypertrophy at the graft-host junctions was observed in78% of the evaluable junctions. In total 11 intramedullary lengthening procedures in 9 patients had been performed at the last follow up. The mean Muskuloskeletal Society Rating Scale(MSTS) score of the evaluable 9 patients was 85% (57% to 100%)with good or excellent results in 7 patients. Conclusions. A-frame vascularised fibula reconstructions showed encouraging results with respect to defect reconstruction, length as well as function and should therefore be considered a valuable option for reconstruction of the distal femur after osteosarcoma resection. The surgical implementation is demanding though, which is emphasized by the considerable high number of com-plications requiring surgical intervention, even though most were not serious

Periprosthetic joint infection (PJI) in geriatric and/or multimorbid patients is an enormous challenge for orthopaedic surgeons. Revision procedures have also been demonstrated to expose patients to higher infection risks. Prior patient stratification according to presumed infection risks, followed by a more potent local antibiotic prophylaxis protocol with selective use of DALBC, is an interesting strategy to decrease the burden of PJI in high risk patients. The PubMed & EMBASE databases were screened for publications pertaining to the utilization of DALBC in cement for infection prophylaxis & prosthesis fixation. 6 preclinical & 7 clinical studies were identified which met the inclusion criteria and were stratified by level of clinical evidence. Only those studies were considered which compared the PJI outcome in the DALBC vs the SALBC group. (1). DALBC have been shown to exert a much stronger and longer lasting inhibition of biofilm formation on many PJI relevant bacteria (gram-positive and gram-negative pathogens) than single gentamicin-only containing cements. (2). DALBC use (COPAL G+C) in the intervention arm of 7 clinical studies has led to a significant reduction of PJI cases in a) cemented hemiarthroplasty procedures (3 studies, evidence level I and III), in b) cemented septic revision surgeries (2 studies, evidence level III), in c) cemented aseptic knee revisions (1 study, evidence level III) and in d) cemented primary arthroplasties in multi-morbid patients (1 study, evidence level III-IV). These benefits were not associated with more systemic side effects or a higher prevalence of broad antimicrobial resistancies. Use of DALBC is likely to be more effective in preventing PJI in high risk patients. The preliminar findings so far may encourage clinicians to consolidate this hypothesis on a wider clinical range

Applications of weightbearing computed tomography (WBCT) imaging in the foot and ankle have emerged over the past decade. However, the potential diagnostic benefits are scattered across the literature, and a concise overview is currently lacking. Therefore, we aimed to systematically review all reported diagnostic applications per anatomical region in the foot and ankle. A systematic literature search was performed in the electronic databases PubMed, EMBASE, Cochrane Library, and Web of Science. Search terms consisted of “weightbearing/standing CT and ankle, hind-, mid- or forefoot”. English language studies analyzing the diagnostic applications of WBCT were included. Studies were excluded if they simulated weightbearing CT, described normal subjects, included cadaveric samples or samples were case reports. The modified Methodological Index for Non-Randomized Studies (MINORS) was applied for quality assessment. The added value was defined as the review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and registered in the Prospero database (CRD42019106980). A total of 48 studies (prospective N=8, retrospective N=36, cohort study N=1, diagnostic N=2, prognostic comparative study N=1) were found to be eligible for review. The following diagnostic applications were identified per anatomical area in the foot: ankle (osteoarthritis N=5, ligament injury N=6); hindfoot (deformity N=9); midfoot (Lisfranc injury N=2, flatfoot deformity N=13, osteoarthritis N=1); forefoot (hallux valgus N=12). The identified studies contained diagnostic applications that could not be used on plain radiographs. The mean MINORS equaled 10.1 on a total of 16 (range: 8 to 12). Diagnostic applications of weightbearing CT imaging are most frequently studied in hindfoot deformity, but other area's areas are on the rise. Post-processing of images was identified as the main added value compared to WBRX. However, the findings should be interpreted with caution as the average quality score was moderate. Therefore, future prospective studies are warranted to consolidate the role of WBCT in diagnostic and therapeutic algorithms

The use of implant biomaterials for prosthetic reconstructive surgery and osteosynthesis is consolidated in the orthopaedic field, improving the quality of life of patients and allowing for healthy and better ageing. However, there is the lack of advanced innovative methods to investigate the potentialities of smart biomaterials, particularly for the study of local effects of implant and osteointegration. Despite the complex process of osseointegration is difficult to recreate in vitro, the growing challenges in developing alternative models require to set-up and validate new approaches. Aim of the present study is to evaluate an advanced in vitro tissue culture model of osteointegration of titanium implants in human trabecular bone. Cubic samples (1.5×1.5 cm) of trabecular bone were harvested as waste material from hip arthroplasty surgery (CE AVEC 829/2019/Sper/IOR); cylindrical defects (2 mm Ø, 6 mm length) were created, and tissue specimens assigned to the following groups: 1) empty defects- CTR-; 2) defects implanted with a cytotoxic copper pin (Merck cod. 326429)- CTR+; 3) defects implanted with standard titanium pins of 6 µm-rough (ZARE S.r.l) -Ti6. Tissue specimens were cultured in mini rotating bioreactors in standard conditions, weekly assessing viability. At the 8-week-timepoint, immunoenzymatic, microtomographic, histological and histomorphometric analyses were performed. The model was able to simulate the effects of implantation of the materials, showing a drop in viability in CTR+, differently from Ti6 which appears to have a trophic effect on the bone. MicroCT and histological analysis supported the results, with lower BV/TV and Tb.Th values observed in CTR- compared to CTR+ and Ti6 and signs of matrix and bone deposition at the implant site. The collected data suggest the reliability of the tested model which can recreate the osseointegration process in vitro and can therefore be used for preliminary evaluations to reduce and refine in vivo preclinical models. Acknowledgment: This work was supported by Emilia-Romagna Region for the project “Sviluppo di modelli biologici in vitro ed in silico per la valutazione e predizione dell'osteointegrazione di dispositivi medici da impianto nel tessuto osseo”