A Gender-Bias-Mitigated, Data-Driven Precision Medicine System to Assist in the Selection of Biological Treatments of Grade 3 and 4 Knee Osteoarthritis: Development and Preliminary Validation of precisionKNEE

Objective To identify key variables predictive of patient responses to microfragmented adipose tissue (MFAT) treatment in knee osteoarthritis (KOA) and evaluate its potential to delay or mitigate the need for total knee replacement (TKR). Methods We utilised a dataset comprising 329 patients treated with MFAT for KOA, incorporating variables such as gender, age, BMI, arthritic aetiology, radiological grade, and Oxford Knee Scores (OKS) pre- and post-treatment. We employed random forest regressors for model training and testing, with gender bias mitigation and outlier detection to enhance prediction accuracy. Model performance was assessed through root mean squared error (RMSE) and mean absolute error (MAE), with further validation in a TKR-suitable patient subset. Results The model achieved a test RMSE of 6.72 and an MAE of 5.38, reflecting moderate predictive accuracy across the patient cohort. Stratification by gender revealed no statistically significant differences between actual and predicted OKS improvements (p-values: males = 0.93, females = 0.92). For the subset of patients suitable for TKR, the model presented an increased RMSE of 9.77 and MAE of 7.81, indicating reduced accuracy in this group. The decision tree analysis identified pre-operative OKS, radiological grade, and gender as significant predictors of post-treatment outcomes, with pre-operative OKS being the most critical determinant. Patients with lower pre-operative OKS showed varying responses based on radiological severity and gender, suggesting a nuanced interaction between these factors in determining treatment efficacy. Conclusion This study highlights the potential of MFAT as a non-surgical alternative for KOA treatment, emphasising the importance of personalised patient assessments. While promising, the predictive model warrants further refinement and validation with a larger, more diverse dataset to improve its utility in clinical decision-making for KOA management.

A Quantum-Enhanced Precision Medicine Application to Support Data-Driven Clinical Decisions for the Personalized Treatment of Advanced Knee Osteoarthritis: The Development and Preliminary Validation of precisionKNEE_QNN

Background Quantum computing and quantum machine learning (QML) are promising experimental technologies that can improve precision medicine applications by reducing the computational complexity of algorithms driven by big, unstructured, real-world data. The clinical problem of knee osteoarthritis is that, although some novel therapies are safe and effective, the response is variable, and defining the characteristics of an individual who will respond remains a challenge. In this study, we tested a quantum neural network (QNN) application to support precision data-driven clinical decisions to select personalized treatments for advanced knee osteoarthritis. Methodology After obtaining patients' consent and Research Ethics Committee approval, we collected the clinicodemographic data before and after the treatment from 170 patients eligible for knee arthroplasty (Kellgren-Lawrence grade ≥3, Oxford Knee Score (OKS) ≤27, age ≥64 years, and idiopathic aetiology of arthritis) treated over a two-year period with a single injection of microfragmented fat. Gender classes were balanced (76 males and 94 females) to mitigate gender bias. A patient with an improvement ≥7 OKS was considered a responder. We trained our QNN classifier on a randomly selected training subset of 113 patients to classify responders from non-responders (73 responders and 40 non-responders) in pain and function at one year. Outliers were hidden from the training dataset but not from the validation set. Results We tested our QNN classifier on a randomly selected test subset of 57 patients (34 responders, 23 non-responders) including outliers. The no information rate was 0.59. Our application correctly classified 28 responders out of 34 and 6 non-responders out of 23 (sensitivity = 0.82, specificity = 0.26, F1 Statistic = 0.71). The positive and negative likelihood ratios were 1.11 and 0.68, respectively. The diagnostic odds ratio was 2. Conclusions Preliminary results on a small validation dataset showed that QML applied to data-driven clinical decisions for the personalized treatment of advanced knee osteoarthritis is a promising technology to reduce computational complexity and improve prognostic performance. Our results need further research validation with larger, real-world unstructured datasets, as well as clinical validation with an artificial intelligence clinical trial to test model efficacy, safety, clinical significance, and relevance at a public health level.

Microbiological Profile of Fracture Related Infection at a UK Major Trauma Centre

Fracture Related Infection (FRI) represents one of the biggest challenges for Trauma and Orthopaedic surgery. A better understanding of the microbiological profile should assist with decision-making and optimising outcomes. Our primary aim was to report on the microbiological profile of FRI cases treated over a six-year period at one of Europe's busiest trauma centres. Secondarily, we sought to correlate our findings with existing anti-microbiological protocols and report on diagnostic techniques employed in our practice. All adult cases of FRI treated in our institution between 2016 and 2021 were identified, retrospectively. We recorded patient demographics, diagnostic strategies, causative organisms and antibiotic susceptibilities. There were 330 infection episodes in 294 patients. A total of 463 potentially pathogenic organisms (78 different species) were identified from cultures, of which 57.2% were gram-positive and 39.7% gram-negative. Polymicrobial cultures were found in 33.6% of cases and no causative organism was found in 17.5%. The most prevalent organisms were Staphylococcus aureus (24.4%), coagulase-negative Staphylococci (14%), Pseudomonas aeruginosa (8.2%), Enterobacter species (7.8%) and Escherichia coli (6.9%). Resistant gram-positive organisms (methicillin resistant Staphylococcus aureus or vancomycin-resistant Enterococci) were implicated in 3.3% of infection episodes and resistant gram-negatives (extended-spectrum beta-lactamase, ampC or carbapenemase-producing bacteria) in 13.6%. The organisms cultured in 96.3% of infection episodes would have been covered by our empirical systemic antibiotic choice of teicoplanin and meropenem. To our knowledge, this is the largest reported single-centre cohort of FRIs from a major trauma centre. Our results demonstrate patterns in microbiological profiles that should serve to inform the decision-making process regarding antibiotic choices for both prophylaxis and treatment.

Complications after talus fractures: A trauma centre experience

BACKGROUND

Talus fractures are anatomically complex, high-energy injuries that can be associated with poor outcomes and high complication rates. Complications include non-union, avascular necrosis (AVN) and post-traumatic osteoarthritis (OA). The aim of this study was to analyse the outcomes of these injuries in a large series.

METHODS

We retrospectively collected data on 100 consecutive patients presenting to a single high volume major trauma centre with a talus fracture between March 2012 and March 2020. All patients were over the age of 18 with a minimum of 12 months follow up post injury. Retrospective review of case notes and imaging was conducted to collate demographic data and to classify fracture morphology. Whether patients were managed non-operatively or operatively was noted and where used, the type of operative fixation, outcomes and complications were recorded.

RESULTS

The mean age was 35 years (range: 18-76 years). Open injuries accounted for 22% of patients. An isolated talar body fracture was the most frequent fracture (47%), followed by neck fractures (20%). The overall non-union rate was 2% with both cases occurring in patients with open fractures. The AVN rate was 6%, with the highest prevalence in talar neck fractures. Overall rates of post-traumatic OA of the tibio-talar, sub-talar and talo-navicular joints were 12%, 8%, and 6%, respectively. These were higher after a joint dislocation, and higher in neck or head fractures. The postoperative infection rate was 6%. The overall secondary surgery rate was 9%. There were 2% of patients who subsequently underwent a joint arthrodesis.

CONCLUSION

Our study found that talar body fractures are more common than previously reported; however, talar neck fractures cause the highest rates of AVN and post-traumatic arthritis. Open fractures also carry a greater risk of complications. This information is useful during consenting and preoperatively when planning these cases to ensure adverse outcomes may be anticipated.

Intramedullary application of local antibiotic bullets for the treatment of long bone fracture related infection

PURPOSE

The optimal means of local antibiotic delivery for fracture related infection is unknown. Until now, intramedullary application of calcium sulphate based local antibiotics has been challenging. We report on the use of a newly available mode of preparation and delivery: the Stimulan Bullet Mat and Introducer (Biocomposites Ltd, Staffordshire, England).

METHODS

A retrospective analysis of prospectively collected data for infection cases at two separate tertiary referral institutions was performed. We included cases of long bone FRI with a retained intramedullary nail, treated with a single stage protocol of metalwork removal, debridement, local antibiotic application using the novel mould and applicator, with additional bony stabilisation and soft tissue reconstruction where required.

RESULTS

All 13 patients achieved infection remission rate with an average follow-up of 19.7 months (range 12-28). All 6 patients with infection around an unhealed fracture achieved union at an average 8 months (range 4-12) from debridement. No patients developed aseptic wound leak.

CONCLUSIONS

Antibiotic impregnated calcium sulphate can be used safely as part of a single stage treatment protocol for the treatment of long bone fracture related infection following intramedullary nailing. We have demonstrated high rates of infection remission and union, using a newly available intramedullary applicator.

A major trauma centre experience with gentamicin-coated tibial intramedullary nails (ETN PROtect™) in acute primary open fracture fixation and complex revision surgery

PURPOSE

Fracture-related infections (FRI) following intramedullary nailing for tibial shaft fractures remain challenging to treat with associated high patient morbidity and health care costs. Recently, antibiotic-coated nails have been introduced as a strategy to reduce implant related infection rates in high-risk patients. We present the largest single-centre case series on ETN PROtect® outcomes reporting on fracture union, infection rates and treatment complications.

METHODS

Fifty-six adult patients underwent surgery with ETN PROtect® between 01/09/17 and 31/12/20. Indications consisted of acute open fractures and complex revision cases (previous FRI, non-union surgery and re-fracture) with a mean of three prior surgical interventions. We report on patient demographics, union rates and deep infection. Minimum follow-up was one year.

RESULTS

One (1.8%) patient developed a deep surgical infection and associated non-union requiring further surgery. In addition, we identified three cases (5.4%) of aseptic non-union following facture treatment with ETN PROtect®. Of the five patients who underwent staged complex revision surgery for established FRI with ETN PROtect®, all had treatment failure with ongoing symptoms of deep infection requiring implant removal and further treatment.

CONCLUSION

Use of the ETN PROtect® nail in high-risk patients (open fractures and those initially treated with external fixation) and in those patients with aseptic non-unions, demonstrates promising outcomes in the prevention of implant-related infection. In our limited series we have failed to observe any benefit over uncoated nails, when used in treating cases of previously established FRI/osteomyelitis and would therefore advise caution in their use, especially in view of the high cost.

Pin-site Infection: A Systematic Review of Prevention Strategies

Introduction

Circular frame fixation remains a key tool in the armamentarium of the limb reconstruction surgeon. One of the key drawbacks is the onset of pin-site infection (PSI). As a result of limited evidence and consensus of PSI prevention, a wide variation in practice remains.

Aim

The principal aim of this review is to synthesise primary research concerning all aspects of treatment regarded as relevant to PSI in frame constructs.

Materials and methods

Comparative studies until week 26, 2021, were included in the trial. Studies were included that concerned patients undergoing management of a musculoskeletal condition in which pin-site care is necessary for over 4 weeks.

Results

Eighteen studies over a 13-year period were captured using the search strategy. Sulphadiazine and hydrogen peroxide cleansing was found to reduce PSI, with the use of low-energy fine wires and hydroxyapatite (HA)-coated pins also associated with lower infection rate. The remainder of studies found no significant improvement across interventions.

Conclusion

There is no superiority between weekly and daily care. Low-energy pin-insertion technique had lower rates of infection. Sulphadiazine has positive results as a pin-care solution, but more research is necessary to determine the most effective care regime. Current literature is limited by absence of established definitions and by a lack of studies addressing all aspects of care relevant to PSI.

How to cite this article

Shields DW, Iliadis AD, Kelly E, et al. Pin-site Infection: A Systematic Review of Prevention Strategies. Strategies Trauma Limb Reconstr 2022;17(2):93–104.

Percutaneous subtalar joint screw fixation of comminuted calcaneal fractures: a salvage procedure

INTRODUCTION

Malunited comminuted calcaneal fractures result in poor function due subtalar joint arthritis and altered biomechanics. We aimed to assess whether percutaneous subtalar joint screws after fracture reduction provide good outcomes for these difficult injuries.

METHODS

We retrospectively analysed 15 comminuted calcaneal fractures (in 14 patients) treated with percutaneous subtalar screw fixation. All patients had a minimum of 12 months' follow-up. Six patients had open injuries. On the preoperative and the latest postoperative radiograph, Bohlers angle, Gissane angle, calcaneal inclination, width and length, absolute foot height, and posterior facet height were measured. Preoperative computed tomography scans were used to classify the fractures by Sanders classification. Clinical outcome scores were recorded postoperatively.

RESULTS

Mean age was 34.2 ± 14.2 years. Minimum follow-up was 12 months (mean 17.2 ± 4.4 months). Nine patients had a Sanders 4, 3 had a Sanders 3AB, 2 had a Sanders 3BC, and 1 had a Sanders 3AC fracture. Eighty percent of patients had their angle of Gissane, absolute foot height, calcaneal length and inclination restored by this technique. Bohlers angle was restored back into the normal range in 54% of patients. Mean postoperative AOFAS score was 74 ± 11. AOFAS scores positively correlated with postoperative Bohlers angle (Pearson's correlation coefficient 0.85; p = 0.004). One patient (7%) had a wound breakdown postoperatively and three patients (20%) had heel pain from the screws, which improved after removal.

CONCLUSION

Percutaneous subtalar screws offer a reliable option to restore calcaneal anatomy in comminuted calcaneal fractures, with low complication rates. Over 80% of patients had their angle of Gissane, calcaneal length and inclination restored, and over 50% of patients had all radiological parameters restored by this technique. It offers the benefits of percutaneous reduction and fixation and this procedure may be considered an effective first stage prior to definitive subtalar fusion. Further work is needed to review the longer-term outcomes and the conversion rate to arthrodesis.

LEVEL OF EVIDENCE

IV (case series), Therapeutic.

Monomeric C-Reactive Protein: Current Perspectives for Utilization and Inclusion as a Prognostic Indicator and Therapeutic Target

Monomeric C-reactive protein (mCRP), once thought to be a figment of the imagination and whose biological activity was ascribed to its sodium azide preservative, has now pronounced itself as a critical molecule playing a direct role in mediating many of the acute and chronic aberrant pathological responses to inflammation. In this focused mini review, we describe the currently attributed pathobiological interactions of mCRP in disease, where its tissue and cellular distribution and deposition have recently been clearly characterized and linked to inflammation and other pathway-associated progression of neurological and cardiovascular complications and deleterious outcomes. and focus upon current opinions as to the diagnostic and prognostic potential of mCRP-plasma circulating protein and define the possible future therapeutics including ongoing research attempting to block CRP dissociation with small molecule inhibitors or prevention of cell surface binding directly using antibodies or modified orphan drug targeting directed towards CRP, inhibiting its cellular interactions and signaling activation. There is no doubt that understanding the full influence of the biological power of mCRP in disease development and outcome will be considered a critical parameter in future stratified treatment.

Medial approach for subtalar distraction bone block arthrodesis

Subtalar distraction bone block arthrodesis is a useful technique commonly employed in the management of calcaneal and talar fracture malunion. Traditionally it is performed via a posterolateral or extensile lateral approach, however such approaches have been associated with wound complications, particularly secondary to the added stress caused by the subtalar distraction crucial to this technique. Medial approaches to the subtalar joint have been used in other procedures but have not been reported in subtalar distraction bone block arthrodesis. A novel case and technique illustrating the medial approach for subtalar distraction bone block arthrodesis is discussed. LEVEL OF CLINICAL EVIDENCE: Level 4.

A novel technique to assess rotational deformities in lower extremities using CT-based motion analysis

Rotational deformities following intramedullary (IM) nailing of tibia has a reported incidence of as high as 20%. Common techniques to measure deformities following IM nailing of tibia are either based on clinical assessment, plain X-rays or Computed Tomography (CT) comparing the treated leg with the uninjured contralateral side. All these techniques are based on examiners manual calculation inherently subject to bias. Following our previous rigorous motion analysis and symmetry studies on hemi pelvises, femurs and orthopaedic implants, we aimed to introduce a novel fully digital technique to measure rotational deformities in the lower legs. Following formal institutional approval from the Imperial College, CT images of 10 pairs of human lower legs were retrieved. Images were anonymized and uploaded to a research server. Three dimensional CT images of the lower legs were bilaterally reconstructed. CT-based motion analysis (CTMA) was used and the mirrored images of the left side were merged with the right side proximally as stationary and distally as moving objects. Discrepancies in translation and rotation were automatically calculated. Our study population had a mean age of 54 ± 20 years. There were six males and four females. We observed a greater variation in translation (mm) of Centre of Mass (COM) in sagittal plane (95% CI − 2.959–.292) which was also presented as rotational difference alongside the antero-posterior direction or Y axis (95% CI .370–1.035). In other word the right lower legs in our study were more likely to be in varus compared to the left side. However, there were no statistically significant differences in coronal or axial planes. Using our proposed fully digital technique we found that lower legs of the human adults were symmetrical in axial and coronal plane. We found sagittal plane differences which need further addressing in future using bigger sample size. Our novel recommended technique is fully digital and commercially available. This new technique can be useful in clinical practice addressing rotational deformities following orthopaedic surgical intervention. This new technique can substitute the previously introduced techniques.

Effect of Demineralized Bone Matrix, Bone Marrow Mesenchymal Stromal Cells, and Platelet-Rich Plasma on Bone Tunnel Healing After Anterior Cruciate Ligament Reconstruction: A Comparative Micro-Computed Tomography Study in a Tendon Allograft Sheep Model

Background:

The effect of demineralized bone matrix (DBM), bone marrow–derived mesenchymal stromal cells (BMSCs), and platelet-rich plasma (PRP) on bone tunnel healing in anterior cruciate ligament reconstruction (ACLR) has not been comparatively assessed.

Hypothesis:

These orthobiologics would reduce tunnel widening, and the effects on tunnel diameter would be correlated with tunnel wall sclerosis.

Study Design:

Controlled laboratory study.

Methods:

A total of 20 sheep underwent unilateral ACLR using tendon allograft and outside-in interference screw fixation. The animals were randomized into 4 groups (n = 5 per group): Group 1 received 4mL of DBM paste, group 2 received 10 million BMSCs in fibrin sealant, group 3 received 12 mL of activated leukocyte-poor platelet-rich plasma, and group 4 (control) received no treatment. The sheep were euthanized after 12 weeks, and micro-computed tomography scans were performed. The femoral and tibial tunnels were divided into thirds (aperture, midportion, and exit), and the trabecular bone structure, bone mineral density (BMD), and tunnel diameter were measured. Tunnel sclerosis was defined by a higher bone volume in a 250-µm volume of interest compared with a 4-mm volume of interest surrounding the tunnel.

Results:

Compared with the controls, the DBM group had a significantly higher bone volume fraction (bone volume/total volume [BV/TV]) (52.7% vs 31.8%; P = .020) and BMD (0.55 vs 0.47 g/cm³; P = .008) at the femoral aperture and significantly higher BV/TV at femoral midportion (44.2% vs 32.9%; P = .038). There were no significant differences between the PRP and BMSC groups versus controls in terms of trabecular bone analysis or BMD. In the controls, widening at the femoral tunnel aperture was significantly greater than at the midportion (46.7 vs 41.7 mm²; P = .034). Sclerosis of the tunnel was common and most often seen at the femoral aperture. In the midportion of the femoral tunnel, BV/TV (r = 0.52; P = .019) and trabecular number (r_S = 0.50; P = .024) were positively correlated with tunnel widening.

Conclusion:

Only DBM led to a significant increase in bone volume, which was seen in the femoral tunnel aperture and midportion. No treatment significantly reduced bone tunnel widening. Tunnel sclerosis in the femoral tunnel midportion was correlated significantly with tunnel widening.

Clinical Relevance:

DBM might have potential clinical use to enhance healing in the femoral tunnel after ACLR.

600 The Use of a Wide-Awake Local Anaesthesia No Tourniquet (WALANT) Technique in Foot and Ankle Procedures - A Randomised Control Trial

Introduction

Wide awake local anaesthesia no tourniquet (WALANT) is a widely used technique in upper limb procedures that has gained increasing popularity during the coronavirus pandemic. The benefit of WALANT for foot and ankle surgeries is less clear, especially in patients with multiple comorbities. The primary aim of this study was to compare post-operative pain levels in patients undergoing ankle fracture fixation. Secondary objectives included comparison of intra-operative patient experiences, clinical outcomes, and patient satisfaction 1-year post-procedure.

Method

129 patients presenting with ankle fractures were enrolled in a multicenter randomised control trial from February 2016 to January 2020. Patients with medial malleolar, lateral malleolar, bimalleolar or trimalleolar fractures received either WALANT (62 patients) or spinal anaesthesia (67 patients). A 5ml solution of 0.9% saline and 2% lidocaine with 1: 100,000 adrenaline was used for WALANT.

Results

Compared to patients who received spinal anaesthesia, those in the WALANT group experienced less post-operative discomfort and were more satisfied 1-year post-procedure (p-value = 0.003). Surgical outcomes were similar for both groups. Cost analysis revealed that WALANT is significantly more economical.

Conclusions

WALANT is an effective and safe anaesthetic for foot and ankle procedures. Without use of a tourniquet, it reduces post-operative pain and so, eases patient recovery.

Outcomes of posterior malleolar fixation in ankle fractures in a major trauma centre

AIMS

Ongoing controversy exists over the indications and benefits of posterior malleolar fixation in ankle fractures. The aim of this pragmatic study was to evaluate the outcomes of posterior malleolar fracture fixation in ankle fractures in the setting of a major trauma centre. Our hypothesis is that posterior malleolus fixation leads to improved clinical outcomes.

METHODS

A total of 320 patients were identified with operatively treated ankle fractures involving a posterior malleolus component, at our institution between January 2012 and January 2018, ensuring a minimum 2 year follow-up. Of these patients, 160 had the posterior malleolus fixed as part of their surgery and 160 did not. Patient demographics, surgical details and complications were assessed. The Manchester-Oxford Foot Questionnaire (MOXFQ) was the primary patient outcome measure.

RESULTS

Fixation of the posterior malleolus was associated with a statistically significant improvement in patient outcomes. Mean MOXFQ score in the unfixed posterior malleolus group was 24.03 (0 - 62), compared to 20.10 (0 - 67) in the fixed posterior malleolus group (p = 0.04). Outcomes were worse with increasing size of posterior malleolar fragment. Metalwork-related issues were higher in the posterior malleolus fixed group (24/160 (15%) versus 10/160 (6.2%)) and re-operation rate was double.

CONCLUSION

This study demonstrates that in the practical setting of a major trauma unit, fixation of the posterior malleolar fracture leads to improved patient outcomes but with increased metalwork risks and reoperation rates.

Characterisation of Novel Angiogenic and Potent Anti-Inflammatory Effects of Micro-Fragmented Adipose Tissue

Adipose tissue and more specifically micro-fragmented adipose tissue (MFAT) obtained from liposuction has recently been shown to possess interesting medicinal properties whereby its application supports pain reduction and may enhance tissue regeneration particularly in osteoarthritis. Here we have characterised samples of MFAT produced using the Lipogems^® International Spa system from eight volunteer individuals in order to understand the critical biological mechanisms through which they act. A variation was found in the MFAT cluster size between individual samples and this translated into a similar variation in the ability of purified mesenchymal stem cells (MSCs) to form colony-forming units. Almost all of the isolated cells were CD105/CD90/CD45+ indicating stemness. An analysis of the secretions of cytokines from MFAT samples in a culture using targeted arrays and an enzyme-linked immunosorbent assay (ELISA) showed a long-term specific and significant expression of proteins associated with anti-inflammation (e.g., interleukin-1 receptor alpha (Il-1Rα) antagonist), pro-regeneration (e.g., hepatocyte growth factor), anti-scarring and pro-angiogenesis (e.g., transforming growth factor beta 1 and 2 (TGFβ1/2) and anti-bacterial (e.g., chemokine C-X-C motif ligand-9 (CXCL-9). Angiogenesis and angiogenic signalling were notably increased in primary bovine aortic endothelial cells (BAEC) to a different extent in each individual sample of the conditioned medium whilst a direct capacity of the conditioned medium to block inflammation induced by lipopolysaccharides was shown. This work characterises the biological mechanisms through which a strong, long-lasting, and potentially beneficial effect can be observed regarding pain reduction, protection and regeneration in osteoarthritic joints treated with MFAT.

Monomeric C-Reactive Protein Localized in the Cerebral Tissue of Damaged Vascular Brain Regions Is Associated With Neuro-Inflammation and Neurodegeneration-An Immunohistochemical Study

Monomeric C-reactive protein (mCRP) is now accepted as having a key role in modulating inflammation and in particular, has been strongly associated with atherosclerotic arterial plaque progression and instability and neuroinflammation after stroke where a build-up of the mCRP protein within the brain parenchyma appears to be connected to vascular damage, neurodegenerative pathophysiology and possibly Alzheimer's Disease (AD) and dementia. Here, using immunohistochemical analysis, we wanted to confirm mCRP localization and overall distribution within a cohort of AD patients showing evidence of previous infarction and then focus on its co-localization with inflammatory active regions in order to provide further evidence of its functional and direct impact. We showed that mCRP was particularly seen in large amounts within brain vessels of all sizes and that the immediate micro-environment surrounding these had become laden with mCRP positive cells and extra cellular matrix. This suggested possible leakage and transport into the local tissue. The mCRP-positive regions were almost always associated with neurodegenerative, damaged tissue as hallmarked by co-positivity with pTau and β-amyloid staining. Where this occurred, cells with the morphology of neurons, macrophages and glia, as well as smaller microvessels became mCRP-positive in regions staining for the inflammatory markers CD68 (macrophage), interleukin-1 beta (IL-1β) and nuclear factor kappa B (NFκB), showing evidence of a perpetuation of inflammation. Positive staining for mCRP was seen even in distant hypothalamic regions. In conclusion, brain injury or inflammatory neurodegenerative processes are strongly associated with mCRP localization within the tissue and given our knowledge of its biological properties, it is likely that this protein plays a direct role in promoting tissue damage and supporting progression of AD after injury.

Mesenchymal stromal cells and platelet-rich plasma promote tendon allograft healing in ovine anterior cruciate ligament reconstruction

PURPOSE

The effect of bone marrow mesenchymal stromal cells (BMSCs) and platelet-rich plasma (PRP) on tendon allograft maturation in a large animal anterior cruciate ligament (ACL) reconstruction model was reported for the first time. It was hypothesised that compared with non-augmented ACL reconstruction, BMSCs and PRP would enhance graft maturation after 12 weeks and this would be detected using magnetic resonance imaging (MRI).

METHODS

Fifteen sheep underwent unilateral tendon allograft ACL reconstruction using aperture fixation and were randomised into three groups (n = 5). Group 1 received 10 million allogeneic BMSCs in 2 ml fibrin sealant; Group 2 received 12 ml PRP in a plasma clot injected into the graft and bone tunnels; and Group 3 (control) received no adjunctive treatment. At autopsy at 12 weeks, a graft maturation score was determined by the sum for graft integrity, synovial coverage and vascularisation, graft thickness and apparent tension, and synovial sealing at tunnel apertures. MRI analysis (n = 2 animals per group) of the signal-noise quotient (SNQ) and fibrous interzone (FIZ) was used to evaluate intra-articular graft maturation and tendon-bone healing, respectively. Spearman's rank correlation coefficient (r) of SNQ, autopsy graft maturation score and bone tunnel diameter were analysed.

RESULTS

The BMSC group (p = 0.01) and PRP group (p = 0.03) had a significantly higher graft maturation score compared with the control group. The BMSC group scored significantly higher for synovial sealing at tunnel apertures (p = 0.03) compared with the control group. The graft maturation score at autopsy significantly correlated with the SNQ (r = - 0.83, p < 0.01). The tunnel diameter of the femoral tunnel at the aperture (r = 0.883, p = 0.03) and mid-portion (r = 0.941, p = 0.02) positively correlated with the SNQ.

CONCLUSIONS

BMSCs and PRP significantly enhanced graft maturation, which indicates that orthobiologics can accelerate the biologic events in tendon allograft incorporation. Femoral tunnel expansion significantly correlated with inferior maturation of the intra-articular graft. The clinical relevance of this study is that BMSCs and PRP enhance allograft healing in a translational model, and biological modulation of graft healing can be evaluated non-invasively using MRI.

Antiseptic Use in Orthopaedic Wounds

Objectives: The aim of this study is to review the available literature addressing the safety and efficacy of antiseptics in surgical wounds. The different antiseptic solutions, irrigation volumes, time scales and delivery methods have been compared so that evidence-based recommendations on antiseptic use in orthopaedic, foot and ankle surgical procedures can be proposed. Methods: A literature search was performed using the online databases Medline and EMBase to identify in-vitro and in-vivo studies pertaining to antiseptic use in an orthopaedic context. Terms including antiseptic, irrigation fluid, bacitracin, hydrogen peroxide, povidone-iodine and chlorhexidine were searched. Literature published in English from inception to July 2020 in which the full text was accessible was considered for inclusion. Cellular and animal studies were included on the basis that authors analysed antiseptic efficacy and/or toxic effect of antiseptic on cells present in orthopaedic wounds. Clinical studies that met the criteria for inclusion in this review assessed antiseptic use in a surgical context, with a focus on foot and ankle procedures.         These included case reports, case series, case control, prospective and retrospective studies as well as randomised controlled trials. Studies were categorised as in-vitro, animal and human studies. Twenty-three, eleven and forty-four studies were identified as in-vitro, animal and       human studies respectively. These have been summarised and presented herein in a narrative format. Results: There is strong evidence that skin preparation with antiseptics before orthopaedic procedures reduces the risk of post-operative infection. Conclusion: Routine prophylactic intra-operative antiseptic use should be performed with caution as they increase the risk of local and systemic complications. However, there is strong evidence supporting the use of antiseptics pre-operatively when preparing the skin. Determining the best antiseptic preparation remains a matter of debate since a single agent or solution is not effective against all organisms. Further research is therefore needed to assess the efficacy of antiseptics in prevention and treatment of infections.

Intra-Operative 3-Dimensional Imaging (O-arm) in Foot and Ankle Trauma Surgery: Report of 2 Cases and Review of the Literature

Background:

Intraoperative two-dimensional (2D) fluoroscopy is the standard imaging modality available to orthopaedic surgeons worldwide. It is well-accepted, however, multiplanar 3 dimensional (3D) CT scanning is superior to 2D imaging for visualising joint surfaces and is now a fundamental feature of the pre-operative planning of intra-articular fractures.

Objective:

We present two cases in which the use of 3D intraoperative imaging and the O-arm® (Medtronic, Minneapolis, USA) led to immediate intraoperative revision to optimise fixation and articular congruity. A review of the current literature is also provided.

Methods:

During the trial period of the O-arm at our major trauma centre, intra-operative imaging was used in the lower limb trauma setting. The O-arm was used intra-operatively in a comminuted pilon fracture and a displaced talus fracture. We recorded all the intra-operative events, including quality of reduction, implant positioning and operation time. Each patient was followed-up for 12 months post-operation and was finally assessed with x-rays and the AOFAS score.

Results:

In both the cases, either fracture reduction or the implant position/usage that was observed with 2D fluoroscopy was revised following a 3D intra-operative scan. No postoperative complications were noted and the healing process was uneventful. X-rays at the final follow-up were excellent and acceptable for the talus and pilon fracture, respectively, with corresponding clinical results and AOFAS score.

Conclusion:

Although frequently used in spinal surgery, to the best of our knowledge, the use of intra-operative 3D techniques in lower limb trauma is sparse and sporadically reported. We present our cases in which the most current innovative imaging techniques influenced intra-operative outcomes without compromising patient safety. We feel that this is a real example of how innovation can positively influence patient care.

What Is the Best Method to Differentiate Acute Charcot Foot From Acute Infection?

RECOMMENDATION

Differentiation between acute Charcot neuroarthropathy (CN) and acute infection/osteomyelitis is complex and requires multiple (>1) diagnostic criteria. These criteria include an emphasis on the presence of neuropathy, history, and physical examination. The absence of skin wounds and resolution of swelling/erythema with elevation makes the likelihood of infection very low. In unclear cases, laboratory testing, histologic examination and culturing of bone specimens, scintigraphy, and imaging, especially magnetic resonance imaging (MRI), may be of benefit.

LEVEL OF EVIDENCE

Moderate.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Is There a Role for the Use of Dilute Povidone-Iodine (Betadine) Irrigation or Other Antiseptic Irrigation Solutions During Total Ankle Arthroplasty (TAA) or Other Foot and Ankle Procedures?

RECOMMENDATION

With regard to total ankle arthroplasty (TAA), there is a lack of evidence to recommend for or against the use of betadine solution.

LEVEL OF EVIDENCE

Consensus.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Should Treatment of Diabetic Foot Osteomyelitis Be Based on Bone Biopsies?

RECOMMENDATION

Yes. Bone biopsies play both a crucial diagnostic and interventional role in the management of diabetic foot infection. Although bone biopsies are not required in every case of diabetic foot infection, their most important role is in guiding accurate antibiotic treatment, as they provide more accurate microbiological information than superficial soft tissue samples in patients with diabetic foot osteomyelitis.

LEVEL OF EVIDENCE

Moderate.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Does Revascularization Prior to Foot and Ankle Surgery Reduce the Incidence of Surgical Site Infection (SSI)?

RECOMMENDATION

Several studies support the effect of peripheral vascular disease (PVD) on wound healing and surgical site infection (SSI). Despite this, there have been no specific studies proving the beneficial effect of revascularization on SSI prior to operative intervention in the setting of traumatic or elective foot and ankle surgery. The majority of studies on revascularization are in the setting of diabetic foot infection or established ischemia. We recommend that in the presence of an inadequate vascularization in the foot and ankle, vascular optimization should be undertaken prior to elective surgery.

LEVEL OF EVIDENCE

Limited.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

What Is the Diagnostic "Algorithm" for Infected Total Ankle Arthroplasty (TAA)?

RECOMMENDATION

Patients who present with clinical symptoms and signs of periprosthetic ankle infection (pain, erythema, warmth, sinus tract, abscess around the wound) and sinus tracts communicating with the ankle/subtalar joint are likely to have total ankle arthroplasty (TAA) infection. In the absence of a sinus tract, elevated inflammatory markers (erythrocyte sedimentation rate [ESR] and C-reactive protein [CRP]) should prompt ankle joint aspiration for cell count, differential, and culture. The joint aspiration is to be repeated. If the same organism is identified in at least 2 cultures of synovial fluid, the patient is diagnosed to have an infection. If the repeat aspiration is negative, further investigation is warranted. In patients not requiring operative intervention for other reasons, nuclear imaging should be considered for diagnosis. If an operation is indicated, histologic examination (>5 neutrophils/high-power field) or synovial fluid analysis is conducted to confirm infection.

LEVEL OF EVIDENCE

Limited.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Treating the Many Using a Few: A Novel Approach for the Application of External Fixators in Mass Casualties

Aim

The aim of this is to allow the use of unsterile kit (clamps and rods) in situations where the demand for external limb fixators exceeds the available sterile equipment.

Background

In view of the recent rise in violence and terrorist activity, we have to be prepared for situations causing major incidences. These can place a large strain on our operating theaters and the available surgical kit due to the potential number of casualties.

Materials and methods

We propose a sterile dressing technique during the application of an external limb fixator that provides an adequate seal around the pin sites and allows the use of simply decontaminated external fixator parts.

Conclusion

This technique prevents the intraoperative contamination of the clamps and connecting rods, which allow for a sterile barrier to minimize pin site infections.

How to cite this article

Vris A, Al-Obaedi O, Vaghela KR, et al. Treating the Many Using a Few: A Novel Approach for the Application of External Fixators in Mass Casualties. Strategies Trauma Limb Reconstr 2019;14(2):92–93.

All Internal Bone Transport: Use of a Lengthening Nail and Double Plating for Management of Femoral Bone Loss

Background

Variety of techniques for management of segmental femoral bone loss have been described, each with different advantages and challenges during treatment. The development of motorized lengthening nails has provided a potential for all internal bone transport, avoiding some of the difficulties with external fixation in the femur. At present, there is limited published literature on experiences in this technique.

Aim

The development of this technique aimed to overcome the difficulties previously reported for internal bone transport in the femur, particularly varus deformity and joint stiffness.

Technique

We describe the technique of double plating with bone transport utilizing a magnetic lengthening nail to manage segmental femoral bone loss. The benefits of the technique are discussed, along with specific challenges and lessons that have been learned through experience of internal bone transport.

Conclusion

Use of a magnetic lengthening nail and double plating as a method of all internal bone transport provides an option for the management of massive femoral bone loss, while avoiding some of the challenges that have been reported with the existing techniques.

Clinical significance

This technique provides an additional method in the armamentarium of the trauma or limb reconstruction surgeon treating massive femoral bone loss.

How to cite this article

Wright J, Bates P, Heidari N, et al. All Internal Bone Transport: Use of a Lengthening Nail and Double Plating for Management of Femoral Bone Loss. Strategies Trauma Limb Reconstr 2019;14(2):94–101.

‘Rail and Nail’ bifocal management of atrophic femoral nonunion

Aims

The management of a significant bony defect following excision of a diaphyseal atrophic femoral nonunion remains a challenge. We present the outcomes using a combined technique of acute femoral shortening, stabilized with a long retrograde intramedullary nail, accompanied by bifocal osteotomy compression and distraction osteogenesis with a temporary monolateral fixator.

Patients and Methods

Eight men and two women underwent the ‘rail and nail’ technique between 2008 and 2016. Proximal locking of the nail and removal of the external fixator was undertaken once the length of the femur had been restored and prior to full consolidation of the regenerate.

Results

The mean lengthening was 7 cm (3 to 11). The external fixator was removed at a mean of 127 days (57 to 220). The mean bone healing index was 28 days/cm and the mean external fixation index was 20 days/cm (11 to 18). There were no superficial or deep infections.

Conclusion

This small retrospective study shows encouraging results for a combined technique, enabling compression of the femoral osteotomy, alignment, and controlled lengthening. Removal of the fixator and proximal locking of the nail reduces the risk of complications and stabilizes the femur with the maximum working length of the nail. Cite this article: Bone Joint J 2018;100-B:634–9.

Evaluation of a cooling/heating-assisted microextraction instrument using a needle trap device packed with aminosilica/graphene oxide nanocomposites, covalently attached to cotton

Evaluation of the first commercial sample of a cooling/heating-assisted microextraction instrument.

Computer hexapod-assisted orthopaedic surgery provides a predictable and safe method of femoral deformity correction

Aims

Computer hexapod assisted orthopaedic surgery (CHAOS), is a method to achieve the intra-operative correction of long bone deformities using a hexapod external fixator before definitive internal fixation with minimally invasive stabilisation techniques. The aims of this study were to determine the reliability of this method in a consecutive case series of patients undergoing femoral deformity correction, with a minimum six-month follow-up, to assess the complications and to define the ideal group of patients for whom this treatment is appropriate.

Patients and Methods

The medical records and radiographs of all patients who underwent CHAOS for femoral deformity at our institution between 2005 and 2011 were retrospectively reviewed. Records were available for all 55 consecutive procedures undertaken in 49 patients with a mean age of 35.6 years (10.9 to 75.3) at the time of surgery.

Results

Patients were assessed at a mean interval of 44 months (6 to 90) following surgery. The indications were broad; the most common were vitamin D resistant rickets (n = 10), growth plate arrest (n = 6) and post-traumatic deformity (n = 20). Multi-planar correction was required in 33 cases. A single level osteotomy was performed in 43 cases. Locking plates were used to stabilise the osteotomy in 33 cases and intramedullary nails in the remainder. Complications included two nonunions, one death, one below-knee deep vein thrombosis, one deep infection and one revision procedure due to initial under-correction. There were no neurovascular injuries or incidence of compartment syndrome.

Conclusion

This is the largest reported series of femoral deformity corrections using the CHAOS technique. This series demonstrates that precise intra-operative realignment is possible with a hexapod external fixator prior to definitive stabilisation with contemporary internal fixation. This combination allows reproducible correction of complex femoral deformity from a wide variety of diagnoses and age range with a low complication rate. Cite this article: Bone Joint J 2017;99-B:283–8.

Assessment of penetration of dorsal screws after fixation of the distal radius using ultrasound: cadaveric study

INTRODUCTION

Volar locking plates are used to treat unstable and displaced fractures of the distal radius. Potential advantages of stable anatomical reduction (eg early mobilisation) can be limited by penetration of dorsal screws, leading to synovitis and potential rupture of extensor tendons. Despite intraoperative imaging, penetration of dorsal screws continues to be a problem in volar plating of the distal radius. Ultrasound is a well recognised, readily available, diagnostic tool used to assess soft-tissue impingement by orthopaedic hardware. In this cadaveric study, we wished to ascertain the sensitivity and specificity of ultrasound for identification of protrusion of dorsal screws after volar plating of the distal radius.

METHODS

Four adult, unpaired phenol-embalmed cadaveric distal radii were used. A VariAx™ Distal Radius Volar Locking Plate system (Stryker, Kalamazoo, MI, USA) was employed for instrumented fixation. A portable SIUI CTS 900 ultrasound machine (Providian Medical, Eastlake, OH, USA) was used to image the dorsal cortex to ascertain screw penetration.

RESULTS

Specificity and sensitivity of ultrasound for detection of screw protrusion through the dorsal cortex was 100%.

CONCLUSIONS

Ultrasound was found to be a safe and accurate method for assessment of dorsal-screw penetration through the dorsal cortex of the radius after volar plating of the distal radius. It also aids diagnosis of associated tendon disorders (eg tenosynovitis) that might cause pain and limit wrist function.

Hardware complications related to the surgical fixation of slipped capital femoral epiphyses

Slipped upper femoral epiphysis is a disabling condition with an annual incidence of 2-13 per 100,000. In situ surgical fixation is the preferred initial treatment for both stable and unstable slipped capital femoral epiphysis (SCFE) cases. The main aim is to avoid further slippage and complications such as osteonecrosis and chondrolysis. The choice of medical implants in managing this condition has changed along the years from large nail-like devices to cannulated screws. The biomechanical properties of different fixation techniques have been studied. All implants have been associated with complications that can occur intraoperatively as well as in the early and late postoperative periods. This report examines a number of different implants used and identifies complications and ways on how to avoid such complications. It also looks at the complications directly related to medical implants in the management of SCFE. We looked at published literature in peer-reviewed journals describing the use of the different medical implants and the documented complications. We also examined literature that suggests ways on how to avoid and manage these complications. A review of the current literature is presented in this text.

Do the presence of pathologic changes and the level of operator experience alter the rate of intra-articular injection of the first metatarsophalangeal joint? A cadaver study

BACKGROUND

Injections, punctures, and aspirations of the first metatarsophalangeal joint are common interventions. Accurate intra-articular placement of the needle is a prerequisite for the achievement of desirable results and the avoidance of complications. We evaluated the rate of successful intra-articular injections and the influence of the degree of operator experience in achieving this success.

METHODS

A total of 106 cadaveric metatarsophalangeal joints were injected with a methylene blue-containing solution and subsequently dissected to distinguish intra-articular from periarticular injections. To evaluate the importance of experience, 38 injections were performed by a student, 38 by a trained resident, and 30 by an experienced surgeon. In the second part of the study, we examined the relation of pathologic findings of the metatarsophalangeal joint and the accuracy of intra-articular injection.

RESULTS

The overall rate of unintentional periarticular injections remained low (9.4%; 10 of 106 joints). The student achieved a successful intra-articular injection in 86.8% of joints (33 of 38), the resident in 92.1% (35 of 38), and the specialist in 93.3% (28 of 30). The number of extra-articular injections increased significantly with the presence of deformity (hallux valgus) and arthritis of the first metatarsophalangeal joint.

CONCLUSIONS

The presence of pathologic changes reduces the rate of successful intra-articular joint puncture. However, the overall frequency of successful intra-articular injections can be improved through experience and the use of imaging.

Fracture of the ulnar styloid process negatively influences the outcome of paediatric fractures of the distal radius

In paediatric patients with fractures of the distal radius, the consequences of associated ulnar styloid fractures are often underestimated. These may include persisting pain or functional deficits. The aim of the present study was to report the outcome of these fractures using a modified DASH-Score. All children with distal radius fractures treated in a two years period were analysed; only patients with a concomitant fracture of the ulnar styloid were included in the study.In addition, children with a non-union of the styloid at cast removal were asked to complete a postal questionnaire; the data were compared to those in a group of patients with isolated distal radius fractures. Patients reporting problems and those with a modified DASH score over 0.5 were invited for a long-term follow-up clinical and radiological examination. A concomitant fracture of the ulnar styloid was present in 11% of all distal radius fractures. At the time of cast removal 46 patients (89%) showed a delayed union of the ulnar styloid. The modified DASH Score of these patients at an average of 31 months (range: 24-40 months) was significantly worse (3.8; range: 0-24.2) compared to 0.7 (range 0-27.7) in the patients with isolated radius fractures after a mean of 27 months (range: 21-42 months). At follow-up, 7 patients showed a non-union of the ulnar styloid. Fractures of the base of the styloid process were more likely to develop non-union compared to fractures of its tip. The presence of an ulnar styloid fracture negatively influences the outcome of distal radius fractures. Patients with lesions of the ulnar styloid should be followed until union is observed and/or they are asymptomatic.

Computer-aided analysis of radial head morphometry

Operative treatment of displaced and comminuted radial head fractures involves internal fixation with plates and screws in cases where reconstruction is possible and replacement with a radial head prosthesis when comminution renders the radial head unreconstructable. The purposes of this study were to evaluate the morphometry of the radial head using a modern technique and to compare the findings with several commercially available radial head prostheses. Computed tomography scans of 30 cadaveric elbows and 3-dimensional reconstructions were used to analyze the morphometry of the proximal radius. Results were compared with the manufacturer data of several radial head prostheses. Mean diameter of the radial head at the level of the fovea was 19±1.58 mm (range, 15.82-21.81 mm) in the anteroposterior plane and 18.62±1.78 mm (range, 15.48-22.21 mm) in the radioulnar plane. Mean diameter of the radial head at its widest part was 23.15±1.94 mm (range, 19.45-26.49 mm) in the anteroposterior plane and 22.44±1.73 mm (range, 19.64-25.44 mm) in the radioulnar plane. Mean diameter of the radial head at the level of the head-neck junction was 15.42±1.59 mm (range, 11.80-18.46 mm) in the anteroposterior plane and 14.75±1.39 mm (range, 12.32-17.31 mm) in the radioulnar plane. Statistically significant sex differences existed in the maximum diameter of the radial head, the diameter at the level of the head-neck junction, and the length of the radial head. Currently available radial head prostheses cover the range of sizes encountered. Products with a choice of head and stem sizes in any combination are preferable. In unstable elbow fractures, correct implant size is an important factor to avoid subluxation of the radial head (Mason type IV fractures) if collateral ligaments are sufficient.

Acetabular fractures in children: a review of the literature

Injury to the acetabular growth plate is rare. Accordingly, data on the incidence in the literature are controverse. Other difficulties include the clear definition of a pediatric acetabular injury. The modified classification according to Salter-Harris described by Bucholz is used in immature patients. The majority of these injuries can be treated conservatively. In severely displaced injuries or in the presence of intra-articular pathologies open procedures are recommended. The main long-term complication is the development of posttraumatic acetabular dysplasia which should be early detected by regular check-ups until the completion of growth. Overall, the long-term results are satisfactory.

The influence of ultrasound guidance in the rate of success of acromioclavicular joint injection: an experimental study on human cadavers

BACKGROUND

Injections of the acromioclavicular joint (ACJ) are performed routinely in patients with ACJ arthritis, both diagnostically and therapeutically. The aim of this prospective controlled study was to estimate the frequency of successful intra-articular ACJ injections with the aid of sonographic guidance versus non-guided ACJ injections.

MATERIALS AND METHODS

A total of 80 cadaveric ACJs were injected with a solution containing methylene blue and subsequently dissected to distinguish intra- from peri-articular injections. In 40 cases the joint was punctured with sonographic guidance, whereas 40 joints were injected in the control group without the aid of ultrasound.

RESULTS

The rate of successful intra-articular ACJ injection was 90% (36 of 40) in the guided group and 70% (28 of 40) in the non-guided group. Ultrasound was significantly more accurate for correct intra-articular needle placement (P = .025).

DISCUSSION

The use of ultrasound significantly improves the accuracy of ACJ injection.