Abstract. Objectives. This abstract provides an update on the Open Ankle Models being developed at the University of Bath. The goal of this project is to create three fully open-source finite element (FE) ankle models, including bones, ligaments, and cartilages, appropriate musculoskeletal loading and boundary conditions, and heterogeneous material property distribution for a standardised representation of ankle biomechanics and pre-clinical ankle joint analysis. Methods. A computed tomography (CT) scan data (pixel size of 0.815 mm, and slice thickness of 1 mm) was used to develop the 3D geometry of the bones (tibia, talus, calcaneus, fibula, and navicular). Each bone was given the properties of a heterogeneous elastic material based on the CT greyscale. The density values for each bone element were calculated using a linear empirical relation, ρ= 0.0405 + (0.000918) HU and then power law equations were utilised to get the Young's Modulus value for each bone element [1]. At the bone junction, a thickness of cartilage ranging from 0.5–1 mm, and was modelled as a linear material (E=10 MPa, ν=0.4 [2]). All ligament insertions and positions were represented by four parallel spring elements, and the ligament stiffness and material attributes were applied in accordance with the published literature [2]. The ankle model was subjected to static loading (balance standing position). Four noded tetrahedral elements were used for the discretization of bones and cartilages. All degrees of freedom were restricted at the proximal ends of the tibia and fibula. The ground reaction forces were applied at the underneath of the calcaneus bone. The interaction between the cartilages and bones was modelled using an augmented contact algorithm with a sliding elastic contact between each cartilage. A tied elastic contact was used between the cartilages and the bone. FEbio 2.1.0 (University of Utah, USA) was used to construct the open-source ankle model. Results. When the double-legged stance phase loading condition was taken into consideration, stress at the antero-medial tibial wall (ranged from 1 to 7 MPa) was found to be similar to the prior work [2], indicating bulk of the load transfer was through this region. The maximum principal strain was predicted at the different regions on bones around the ankle joint. The proximal surface of the talus, and tibial distal surface were shown to have the highest maximum principal strains followed by antero-medial walls of the tibia bone, at the proximal location. Conclusions. The present open 3D FE model of the ankle will assist researchers in better understanding ankle biomechanics, precisely predicting load transfer, and examining the ankle to address unmet clinical needs for this joint. The results of the current investigation are realistic in terms of load transfer and stress-strain distribution across the ankle joint and well comparable to those reported in the literature [2]. However, sensitivity and ankle instability simulations will be performed in future work to investigate the model's reliability and robustness. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Swelling following an ankle fracture is commonly believed to preclude surgical fixation, delaying operative treatment to allow the swelling to subside. This is in an attempt to achieve better soft tissue outcomes. We aim to identify whether pre-operative ankle swelling influences postoperative wound complications following ankle fracture surgery. This is a prospective cohort study of 80 patients presenting to a tertiary referral centre with operatively managed malleolar ankle fractures. Ankle swelling was measured visually and then quantitatively using the validated ‘Figure-of-eight’ technique. Follow-up was standardised at 2, 6, and 12 weeks post-operatively. Wound complications, patient co-morbidities, operative time, surgeon experience, and hospital stay duration were recorded. The complication rate was 8.75% (n=7), with 1 deep infection requiring operative intervention and all others resolving with oral antibiotics and wound cares. There was no significant difference in wound complication rates associated with quantitative ankle swelling (p=0.755), visual assessment of ankle swelling (p=0.647), or time to operative intervention (p=0.270). Increasing age (p=0.006) and female gender (p=0.049) had a significantly greater probability of wound complications. However, BMI, smoking status, level of the operating surgeon, and tourniquet time were not significantly different. Visual assessment of ankle swelling had a poor to moderate correlation to ‘Figure-of-eight’ ankle swelling measurements ICC=0.507 (0.325- 0.653). Neither ankle swelling nor time to surgery correlates with an increased risk of postoperative wound complication in surgically treated malleolar ankle fractures. Increasing patient age and female gender had a significantly greater probability of wound infection, irrespective of swelling. Visual assessment of ankle swelling is unreliable for quantifying true ankle swelling. Operative intervention at any time after an ankle fracture, irrespective of swelling, is safe and showed no better or worse soft tissue outcomes than those delayed for swelling

Background. Lateral ankle instability is a common problem, but the precise role of the lateral ankle structures has not been accurately investigated. This study aimed to accurately investigate lateral ankle complex stability for the first time using a novel robotic testing platform. Method. A six degrees of freedom robot manipulator and a universal force/torque sensor were used to test 10 foot and ankle specimens. The system automatically defined the path of unloaded plantar/dorsi flexion. At four flexion angles: 20° dorsiflexion, neutral flexion, 20° and 40° of plantarflexion; anterior-posterior (90N), internal-external (5Nm) and inversion-eversion (8Nm) laxity were tested. The motion of the intact ankle was recorded first and then replayed following transection of the lateral retinaculum, Anterior Talofibular Ligament (ATFL) and Calcaneofibular Ligament (CFL). The decrease in force/torque reflected the contribution of the structure to restraining laxity. Data were analysed using repeated measures of variance and paired t-tests. Results. The ATFL was the primary restraint to anterior drawer (P< 0.01) and the CFL the primary restraint to inversion throughout range (P< 0.04), but with increased plantarflexion the ATFL's contribution increased. The ATFL had a significant role in resisting tibial external rotation, particularly at higher levels of plantarflexion, contributing 63% at 40° (P< 0.01). The CFL provided the greatest resistance to external tibial rotation, 22% at 40° plantarflexion (P< 0.01). The extensor retinaculum and skin did not offer significant restraint in any direction tested. Conclusion. This study shows accurately for the first time the significant role the ATFL and CFL have in rotational ankle stability. This significant loss in rotational stability may have implications in the aetiology of osteophyte formation and early degenerative changes in patients with chronic ankle instability. This is the first time the role of the lateral ankle complex has been quantified using a robotic testing platform

Introduction. Chronic ankle instability is a common condition that can be effectively treated with arthroscopic lateral ankle ligament reconstruction to restore ankle stability and function. The aim of this study was to assess the functional outcomes of arthroscopic lateral ligament reconstruction using the MOXFQ, VAS, and EQ5D patient-reported outcome measures (PROMs). Methods. This prospective series included 38 patients who underwent arthroscopic lateral ligament reconstruction for chronic ankle instability between December 2019 and April 2022. All patients completed the MOXFQ, VAS, and EQ5D PROMs preoperatively, as well as at6, and 12 months postoperatively. The MOXFQ is a disease-specific PROM that assesses foot and ankle function, while the VAS measures pain and the EQ5D evaluates health-related quality of life. Results. At the 12-month follow-up, the mean MOXFQ Index score had improved significantly from 53.3 ± 23.1 preoperatively to 16.0 ±21.1 (p < 0.001). Similarly, the mean VAS score had improved from 36.2 ± 22.4 preoperatively to 14.7 ± 15.0 (p < 0.001), and the meanEQ5D score had improved from 0.55 ± 0.26 preoperatively to 0.87 ± 0.12 (p < 0.001). No major complications were observed. Conclusion. Arthroscopic lateral ligament reconstruction is an effective treatment for chronic ankle instability, with significant improvements in clinical and health-related quality of life outcomes

Introduction. Fibula contributes to weight bearing and serves as a lateral buttress to the talus. Fibular shortening leads to ankle valgus, distal tibial epiphyseal wedging and ankle instability. Trauma, infection and skeletal dyplasias are the common causes of fibular shortening in children. Aim was to review this cohort who underwent fibular lengthening and ankle reconstruction. Materials and Methods. Retrospective review from a prospective database of clinical and radiographic data of all children who underwent fibular lengthening for correction of ankle valgus. Distraction osteogenesis with external fixator was performed for all cases. Results. Eight children with 10 fibulae (average age: 10 years) were followed up for an average of 75.6 months. In older children, corrective tibial osteotomy was performed in addition to fibular lengthening. TSF frame mounted with mini-rail fixator was used in seven children who required adjuvant tibial correction and mini-rail was used for bilateral fibular lengthening in one. Remodelling of the wedged distal tibial epiphysis was noted in 75%. Talar tilt and mLDTA improved in 66.7% and fibular station in 85.7% limbs. Seven year old girl required re-lengthening. Two children developed fibular non-union. Proximal fibular migration was observed in one child, in whom the tibial wire did not engage the fibula. Conclusions. Restoration of tibial mechanical axis and lateral talar buttress is necessary to correct ankle valgus. Stabilisation of fibula to the tibia is prudent during distraction. Younger children may require re-lengthening. Remodelling of the triangular tibial epiphysis can be achieved when done early

Introduction. The management of open or unstable ankle and distal tibial fractures pose many challenges. In certain situations, hindfoot nailing (HFN) is indicated, however this depends on surgeon preference and regional variations exist. This study sought to establish the current management and outcomes of complex ankle fractures in the UK. Methods. A National collaborative study in affiliation with BOTA was conducted and data retrospectively collected between January 1. st. – June 30. th. 2019. Adult patients with open and closed complex ankle fractures (AO43/44) were included. Complex fractures included the following patient characteristics: diabetes ± neuropathy, rheumatoid arthritis, alcoholism, polytrauma and cognitive impairment. We obtained data on fixation choice and patient outcomes. Institutional approval was obtained by all centres, and statistical analysis was performed including propensity matching. Results. Fifty-six centres provided data for 1360 patients. The average age of the cohort was 53.9 years ±19 (SD) with a male/female ratio of 1:1.3. 920 patients were ASA 1/2, 440 were ASA 3/4; 316 had diabetes, and 275 were open fractures. Most fractures were AO44 (71.2%) and more commonly associated with diabetes (P<0.001), alcoholism (P<0.007), open (P<0.013), and advanced age (55.7 vs. 46.3). 1227 patients underwent primary-fixation (111 HFN), with the remainder treated with external-fixation (84 definitive). Of the 111 HFN, 35% underwent primary fusion. Wound complication and thromboembolic rates were greater in the HFN group compared to ORIF groups (P<0.003), being more evident in the HFN group with primary fusion even after propensity matching. However, 1081 patients were non-weightbearing post-op contrary to the BOAST guidance. Conclusion. This is the first National collaborative audit of complex ankle fractures. Hindfoot nails were used in 9% of patients and we observed more complications in this group when compared to other cohorts. Despite BOAST guidance, only 21% of patients undergoing operative management were instructed to fully weightbear post-operatively

Fragility ankles fractures in the geriatric population are challenging to manage, due to fracture instability, soft tissue compromise, patient co-morbidities. Traditional management options include open reduction internal fixation, or conservative treatment, both of which are fraught with high complication rates. We aimed to present functional outcomes of elderly patients with fragility ankle fractures treated with tibiotalocalcaneal nails. 171 patients received a tibiotalocalcaneal nail over a six-year period, but only twenty met the inclusion criteria of being over sixty and having poor bone stock, verified by radiological evidence of osteopenia or history of fragility fractures. Primary outcome was mortality risk from co-morbidities, according to the Charlson co-morbidity index (CCI), and patients’ post-operative mobility status compared to pre-operative mobility. Secondary outcomes include intra-operative and post-operative complications, six-month mortality rate, time to mobilisation and union. The mean age was 77.82 years old, five of whom are type 2 diabetics. The average CCI was 5.05. Thirteen patients returned to their pre-operative mobility state. Patients with low CCI are more likely to return to pre-operative mobility status (p=0.16; OR=4.00). Average time to bone union and mobilisation were 92.5 days and 7.63 days, respectively. Mean post-operative AOFAS ankle-hindfoot and Olerud-Molander scores were 53.0 (range 17-88) and 50.9 (range 20-85), respectively. There were four cases of broken distal locking screws, and four cases of superficial infection. Patients with high CCI were more likely to acquire superficial infections (p=0.264, OR=3.857). There were no deep infections, periprosthetic fractures, nail breakages, non-unions. TTC nailing is an effective treatment methodology for low-demand geriatric patients with fragility ankle fractures. This technique leads to low complication rates and early mobilisation. It is not a life-changing procedure, with many able to return to their pre-operative mobility status, which is important for preventing the loss of socioeconomic independence

Background. In fixation of the fibula in ankle fractures, AO advocate using a lag screw and one-third tubular neutralisation plate for simple patterns. Where a lag screw cannot be placed, bridging fixation is required. A local pilot service evaluation previously identified variance in use of locking plates in all patterns with significant cost implications. The FAIR study aimed to evaluate current practice and implant use across the United Kingdom (UK) and review outcomes and complication rates between different fibula fixation methods. Method. The study was supported by CORNET, the North East trainee research collaborative, and BOTA. Data was collected using REDCap from 22 centres in the UK retrospectively for a one-year period between 1. st. January 2019 and 31. st. December 2019 on injury mechanism, fracture characteristics, comorbidities, fixation and complications. Follow-up data was collected to at least two-years from the time surgery. Results. 1448 ankle fractures which involved fixation of the fibula were recorded; one-third tubular plate was used in 866 (59.8%) cases, a locking plate in 463 (32.0%) cases and other methods in 119 (8.2%) cases. There was significant difference between centres (p<0.001) in implant type used. Other factors associated with implant type were age, diabetes, osteoporosis, open fractures, fracture pattern and the presence of comminution. Incidence of lateral wound breakdown was higher in locking plates than one-third tubular plates (p<0.05). There was no significant difference in infection, non-union, fixation failure or removal of metalware. Conclusion. There is significant variation in practice in the UK in implant use for fixation of the fibula in ankle fractures. Potentially unnecessary use of locking plates, where a one-third tubular shows equivalent outcomes, incurs additional cost and may increase the risk of lateral wound breakdown. We would encourage surgeons with high locking plate usage to evaluate their own unit's practice against this data

The ankle radiograph is a commonly requested investigation as the ankle joint is commonly injured. Each radiograph exposes 0.01 mSv of radiation to the patient that is equivalent to 1.5 days of natural background radiation [1]. The aim of the clinical audit was to use the Ottawa Ankle Rule to attempt to reduce the number of ankle radiographs taken in patients with acute ankle injuries and hence reduce the dose of ionising radiation the patient receives. A retrospective audit was undertaken. 123 ankle radiograph requests and radiographs taken between May and July 2018 were evaluated. Each ankle radiograph request including patient history and clinical examination was graded against the Ottawa Ankle Rule. The rule states that 1 point(s) indicates radiograph series; (1) malleolar and/or midfoot pain; (1) tenderness over the posterior 6cm or tip of the lateral or medial malleolus (ankle); (1) tenderness over the navicular or the base of the fifth metatarsal (foot); (1) unable to take four steps both immediately and in the emergency department [2]. Patients who score 0 do not need radiograph series. Each radiograph was reviewed if a fracture was present or not. The clinical audit identified 14 true positives where the Ottawa Ankle Rule scored 1 and the patient had an ankle fracture, and 2 false negatives (sensitivity 88%). There were 81 false positives, and 23 true negatives (specificity 22%). Therefore, a total of 23/123 ankle radiographs were unnecessary which is equivalent to 34.5 days of background radiation. The negative predictive value of the Ottawa Ankle Rule in this audit was 92%. The low rate of Ottawa rule utilisation may unnecessarily cause patient harm that should be addressed. An educational intervention with physicians combined with integration of the Ottawa rule scoring in ankle radiograph requests is planned with re-audit in 6 months

One assumed function of Total Ankle Replacement (TAR) is that by maintaining ankle joint motion we can protect the other hind foot joints from further degredation. 1. However, there is no work to our knowledge that compares hindfoot outcomes between TAR and arthrodesis. Sokolowski et al. found that 68% of TAR patients had no radiological progression of subtalar arthritis after TAR, and 4% went on to fusion. 2. However, no evaluation of the other hindfoot joints was made and no comparison made to other treatment. We performed a retrospective review of all patients at our centre who had had a TAR or ankle arthrodesis since 2002. Case notes and imaging were reviewed and all instances of hindfoot treatment (injections or surgical procedures) noted. Patients were excluded who had no documentation, were followed up at other hospitals, had prior hindfoot fusion, or were having staged surgeries at the time of index treatment. Chi squared analysis was used to compare the cohorts. 214 arthrodesis cases and 302 TAR were eligible. The average age was 57. Average time to follow up was 13 years (4–21). At the time of abstract submission 107 sets of notes had been reviewed fully. Full analysis will be performed by conference. 14% of TAR patients went on to have further procedures to the hindfoot joints while 35% of arthrodesis patients had further procedures (p=0.014). There was also a significant difference in the number of patients progressing to fusion of a further hindfoot joint between groups (TAR- 4%, arthrodesis- 20%, p=0.01). These data suggest that TAR are protective of symptomatic change of hindfoot joints. Patients with TAR had fewer hindfoot fusions than those with arthrodesis and also fewer procedures of any form, including injections

The purpose of this study was to define the risk and incidence of eventual ankle arthroplasty or fusion after documented ankle fracture in a large cohort, and compare that rate to matched healthy patients from the general population. The Ontario health insurance plan (OHIP) physician billing database, Institute for Clinical Evaluative Sciences (ICES) Physician Database, the Canadian Institute for Health Information (CIHI) databases, Discharge Abstract Database (DAD) and Same Day Surgery (SDS) were used to identify patients treated surgically and non-surgically for ankle fractures. Each patient was matched to four individuals from the general population (13.5 million) with no documented prior treatment for ankle fracture, according to age, sex, income, and urban/rural residence. Fusion and replacement incidence was compared using time-to-event analysis (Kaplan-Meier). A Cox Proportional Hazards model was used to explore the influence of patient, provider and surgical factors on time to surgery. We identified 45,444 (58.8% female, mean age 48.7 years) and 140, 629 (53.9% female, mean age 47.1 years) patients who had undergone open reduction internal fixation (ORIF) or non-operative management of an ankle fracture (NOA), respectively. Among ORIF patients, n=237 (0.5%) and n=69 (0.15%) patients underwent fusion or arthroplasty after a median 2.8 and 6.9 years, respectively. Among non-operatively treated ankle fractures, n=198 (0.14%) and n=36 (0.03%) patients underwent fusion or arthroplasty after a median of 3.2 and 5.6 years, respectively. Surgical treatment (vs. non-operatively treated fracture), older age, greater co-morbidity and a history of infection post fracture significantly increased the risk of eventual fusion or arthroplasty (HR 3.6 (3.1–4.3), p < 0 .001, HR 1.01 (1.01–1.02), p=0.009, HR 1.2 (1.1–1.3), p < 0 .001, HR 11.3 (6.8–18.7), p < 0 .001, respectively). Compared to matched controls, the risk of fusion/arthroplasty was not independent of time, following an exponential decay pattern. ORIF patient risk was 20 times greater than the general population in the first three years post-ORIF, and approached the risk of non-operatively treated patients (HR 4.5 (95CI: 3.5–5.8), p < 0 .0001) by approximately 14 years out from injury on time and comorbidity adjusted KM curves. Rates of fusion/arthroplasty are very low after ORIF and non-operative treatment of an ankle fracture in the general population of a public healthcare system. Utilization patterns suggest fusion is more common earlier, and arthroplasty remote, which may be a factor of patient age, injury severity, and complications from initial injury/surgery. Patients who underwent ORIF have >20 times the risk of fusion/arthroplasty in the short-term, however, the risk decreases over time eventually approaching that of non-operatively treated patients (∼4.5x the general population) when compared to non-fractured controls

Syndesmotic ankle lesions involve disruption of the osseous tibiofibular mortise configuration as well as ligamentous structures stabilizing the ankle joint. Incomplete diagnosis and maltreatment of these injuries is frequent, resulting in chronic pain and progressive instability thus promoting development of ankle osteoarthritis in the long term. Although the pathogenesis is not fully understood, abnormal mechanics has been implicated as a principal determinant of ankle joint degeneration after syndesmotic ankle lesions. Therefore, the focus of this presentation will be on our recent development of a computationally efficient algorithm to calculate the contact pressure distribution in patients with a syndesmotic ankle lesion, enabling us to stratify the risk of OA development in the long term and thereby guiding patient treatment

Ligament integrity is directly associated with ankle stability. Nearly 40% of ankle sprains result in chronic ankle instability, affecting biomechanics and potentially causing osteoarthritis. Ligament replacement could restore stability and avoid this degenerative pathway, but a greater understanding of ankle ligament behaviour is required. Additionally, autograft or allograft use is limited by donor-site morbidity and inflammatory responses respectively. Decellularised porcine grafts could address this, by removing cellular material to prevent acute immune responses, while preserving mechanical properties. This project will characterise commonly injured ankle ligaments and damage mechanisms, identify ligament reconstruction requirements, and investigate the potential of decellularised porcine grafts as a replacement material. Several porcine tendons were evaluated to identify suitable candidates for decellularisation. The viscoelastic properties of native tissues were assessed using dynamic mechanical analysis (DMA), followed by ramp to ‘sub-rupture’ at 1% strain/s, and further DMA. Multiple samples (n=5) were taken along the graft to assess variation along the tendon. When identifying suitable porcine tendons, a lack of literature on human ankle ligaments was identified. Inconsistencies in measurement methods and properties reported makes comparison between studies difficult. Preliminary testing on porcine tendons suggested there is little variation in viscoelastic properties along the length of tendon. Testing also suggested strain rates of 1%/s sub-rupture was not large enough to affect viscoelastic properties (no changes in storage or loss moduli or tanẟ). Further testing is underway to improve upon low initial sample numbers and confirm these results, with varying strain rates to identify suitable sub-rupture sprain conditions. This work highlights need for new data on human ankle ligaments to address knowledge gaps and identify suitable replacement materials. Future work will generate this data and decellularise porcine tendons of similar dimensions. Collagen damage will be investigated using histology and lightsheet microscopy, and viscoelastic changes through DMA

Diabetes mellitus is a risk factor for complications after operative management of ankle fractures. Generally, diabetic sequelae such as neuropathy and nephropathy portend greater risk; however, the degree of risk resulting from these patient factors is poorly defined. We sought to evaluate the effects of the diabetic sequelae of neuropathy, chronic kidney disease (CKD), and peripheral vascular disease (PVD) on the risk of complications following operative management of ankle fractures. Using a national claims-based database we analyzed patients who had undergone operative management of an ankle fracture and who remained active in the database for at least two years thereafter. Patients were divided into two cohorts, those with a diagnosis of diabetes and those without. Each cohort was further stratified into five groups: neuropathy, CKD, PVD, multiple sequelae, and no sequelae. The multiple sequelae group included patients with more than one of the three sequelae of interest: CKD, PVD and neuropathy. Postoperative complications were queried for two years following surgery. The main complications of interested were: deep vein thrombosis (DVT), surgical site infection, hospital readmission within 90 days, revision internal fixation, conversion to ankle fusion, and below knee amputation (BKA). We identified 210,069 patients who underwent operative ankle fracture treatment; 174,803 had no history of diabetes, and 35,266 were diabetic. The diabetic cohort was subdivided as follows: 7,506 without identified sequelae, 8,994 neuropathy, 4,961 CKD, 1,498 PVD, and 12,307 with multiple sequelae. Compared to non-diabetics, diabetics without sequelae had significantly higher odds of DVT, infection, readmission, revision internal fixation and conversion to ankle fusion (OR range 1.21 – 1.58, p values range Compared to uncomplicated diabetics, diabetics with neuropathy alone and diabetics with multiple sequelae were found to have significantly higher odds of all complications (OR range 1.18 – 31.94, p values range < 0.001 - 0.034). Diabetics with CKD were found to have significantly higher odds of DVT, readmission, and BKA (OR range 1.34 – 4.28, p values range < 0.001 - 0.002). Finally, diabetics with PVD were found to have significantly higher odds of DVT, readmission, conversion to ankle fusion, and BKA (OR range 1.62 - 9.69, p values range < 0.001 - 0.039). Diabetic patients with sequelae of neuropathy, CKD or PVD generally had higher complication rates than diabetic patients without these diagnoses. Unsurprisingly, diabetic patients with multiple sequalae are at the highest risk of complications and had the highest odds ratios of all complications. While neuropathy is known to be associated with postoperative complications, our analysis demonstrates that CKD represents a significant risk factor for multiple complications following the operative management of ankle fractures and has rarely been discussed in prior studies

The incisura fibularis (IF) provides intrinsic stability to the ankle joint complex by interlocking the distal tibia and fibula. Despite a high frequency of ligamentous ankle injuries, scant attention has been given to the morphology of the IF morphology incisura fibularis in the onset and development of these lesions. Therefore, we systematically reviewed the relation between ligamentous ankle disorders and the morphometrics of the IF. A systematic literature search was conducted on following databases: PubMed, Embase and Web of Science. Search terms consisted of ‘ankle trauma’, ‘ankle injury’, ‘ankle sprain’, ‘ankle fracture’, ‘tibiofibular’, ‘fibular notch’, ‘fibular incisura’, ‘incisura fibularis’, ‘morphometric analysis’, ‘ankle syndesmosis’, ‘syndesmotic stability’. The evaluation instrument developed by Hawker et al. was used to assess the quality of the selected studies. This protocol was performed according to the PRISMA guidelines and is registered on PROSPERO (CRD42021282862). Nineteen studies were included and consisted of prospective cohort (n=1), retrospective comparative (n=10), and observational (n=8) study design. Comparative studies have found certain morphological characteristics in patients with ankle instability. Several studies (n=5) have correlated a shallow IF depth with a higher incidence of ankle injury. A significant difference has also been found concerning the incisura height and angle (n=3): a shorter incisura and more obtuse angle have been noted in patients with ankle sprains. The mean Hawker score was 28 out of 36 (range=24-31). A shallower IF is associated with ligamentous ankle lesions and might be due to a lower osseous resistance against tibiofibular displacement. However, these results should be interpreted in light of moderate methodological quality and should always be correlated with clinical findings. Further prospective studies are needed to further assess the relation between the incisura morphometrics and ligamentous disorders of the ankle joint. Keywords: ankle instability, ankle injury, incisura fibularis, fibular notch, tibiofibular morphometrics, ankle syndesmosis

Aim. Ankle fracture surgery comes with a risk of fracture-related infection (FRI). Identifying risk factors are important in preoperative planning, in management of patients, and for information to the individual patient about their risk of complications. In addition, modifiable factors can be addressed prior to surgery. The aim of the current paper was to identify risk factors for FRI in patients operated for ankle fractures. Method. A cohort of 1004 patients surgically treated for ankle fractures at Haukeland University hospital in the period of 2015–2019 was studied retrospectively. Patient charts and radiographs were assessed for the diagnosis of FRI. Binary logistic regression was used in analyses of risk factors. Regression coefficients were used to calculate the probability for FRI based on the patients’ age and presence of one or more risk factors. Results. FRI was confirmed in 87 (9%) of 1004 patients. Higher age at operation (p < 0.001), congestive heart failure (CHF), p = 0.006), peripheral artery disease (PAD, p = 0.001), and current smoking (p = .006) were identified as risk factors for FRI. PAD and CHF were the risk factors displaying the strongest association with FRI with an adjusted odds ratio of 4.2 (95% CI 1.8–10.1) and 4.7 (95% CI 1.6–14.1) respectively. Conclusions. The prevalence of FRI was 9% after surgical treatment of ankle fractures. The combination of risk factors found in this study demonstrate the need for a thorough, multidisciplinary, and careful approach when faced with an elderly or frail patient with an ankle fracture. The results of this study help the treating surgeons to inform their patients of the risk of FRI prior to ankle fracture surgery

Abstract. The lateral ligaments of the ankle composed of the anterior talofibular (ATFL), calcaneofibular (CFL) and posterior talofibular ligaments (PTFL), are amongst the most commonly injured ligaments of the human body. Although treatment methods have been explored exhaustively, healing outcomes remain poor with high rates of re-injury, chronic ankle instability and pain persisting. The introduction and application of tissue engineering methods may target poor healing outcomes and eliminate long-term complications, improving the overall quality of life of affected individuals. For any surgical procedure or tissue-engineered replacement to be successful, a comprehensive understanding of the complete anatomy of the native structure is essential. Knowledge of the dimensions of ligament footprints is vitally important for surgeons as it guides the placement of bone tunnels during repair. It is also imperative in tissue-engineered design as the creation of a successful replacement relies on a thorough understanding of the native anatomy and microanatomical structure. Several studies explore techniques to describe ligament footprints around the body, with limited studies describing in-depth footprint dimensions of the ATFL, CFL and PTFL. Techniques currently used to measure ligament footprints are complex and require resources which may not be readily available, therefore a new methodology may prove beneficial. Objectives. This study explores the application of a novel technique to assess the footprint of ankle ligaments through a straightforward inking method. This method aims to enhance surgical technique and contribute to the development of a tissue-engineered analogue based on real anatomical morphometric data. Methods. Cadaveric dissection of the ATFL, CFL and PTFL was performed on 12 unpaired fresh frozen ankles adhering to regulations of the Human Tissue (Scotland) Act. The ankle complex with attaching ligaments was immersed in methylene blue. Dissection of the proximal and distal entheses of each ligament was carried out to reveal the unstained ligament footprint. Images of each ligament footprint were taken, and the area, length and width of each footprint were assessed digitally. Results. The collective area of the proximal entheses of the ATFL, CFL and PTFL measures 142.11 ± 12.41mm2. The mean areas of the superior (SB) and inferior band (IB) of the distal enthesis of the ATFL measured 41.72 ± 5.01mm2 and 26.66 ± 3.12mm2 respectively. The footprint of the distal enthesis of the CFL measured 146.07 ± 14.05mm2, while the footprint of the distal PTFL measured 126.26 ± 8.88mm2. The proximal footprint of the ATFL, CFL and PTFL measured 11.06 ± 0.69mm, 7.87 ± 0.43mm and 10.52 ± 0.63mm in length and 8.66 ± 0.50mm, 9.10 ± 0.92mm and 14.41 ± 1.30mm in width on average. The distal footprint of the ATFL (SB), ATFL (IB), CFL and PTFL measured 10.92 ± 0.81 mm, 8.46 ± 0.46mm, 13.98 ± 0.93mm and 11.25 ± 0.95mm in length and 7.76 ± 0.59mm, 7.51 ± 0.64mm, 18.98 ± 1.15mm and 24.80 ± 1.25mm in width on average. Conclusions. This methodology provides an effective approach in the identification of the footprint of the lateral ligaments of the ankle to enhance surgical precision and accuracy in tissue-engineered design. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Background. Ankle fractures are often associated with ligamentous injuries of the distal tibiofibular syndesmosis, the deltoid ligament and are predictive of ankle instability, early joint degeneration and long-term ankle dysfunction. Detection of ligamentous injuries and the need for treatment remain subject of ongoing debate. In the classic article of Boden it was made clear that injuries of the syndesmotic ligaments were of no importance in the absence of a deltoid ligament rupture. Even in the presence of a deltoid ligament rupture, the interosseous membrane withstood lateralization of the fibula in fractures up to 4.5mm above the ankle joint. Generally, syndesmotic ligamentous injuries are treated operatively by temporary fixation performed with positioning screws. But do syndesmotic injuries need to be treated operatively at all?. Methods. The purpose of this biomechanical cadaveric study was to investigate the relative movements of the tibia and fibula, under normal physiological conditions and after sequential sectioning of the syndesmotic ligaments. Ten fresh-frozen below-knee human cadaveric specimens were tested under normal physiological loading conditions. Axial loads of 50 Newton (N) and 700N were provided in an intact state and after sequential sectioning of the following ligaments: anterior-inferior tibiofibular (AITFL), posterior-inferior tibiofibular (PITFL), interosseous (IOL), and whole deltoid (DL). In each condition the specimens were tested in neutral position, 10 degrees of dorsiflexion, 30 degrees of plantar flexion, 10 degrees of inversion, 5 degrees of eversion, and externally rotated up to 10Nm torque. Finally, after sectioning of the deltoid ligament, we triangulated Boden's classic findings with modern instruments. We hypothesized that only after sectioning of the deltoid ligament; the lateralization of the talus will push the fibula away from the tibia. Results. During dorsiflexion and external rotation the ankle syndesmosis widened, and the fibula externally rotated after sequential sectioning of the syndesmotic ligaments. After the AITFL was sectioned the fibula starts rotating externally. However, the external rotation of the fibula significantly reduced when the external rotation torque was combined with axial loading up to 700N as compared to the external rotation torque alone. The most relative moments between the tibia and fibula were observed after the deltoid ligament was sectioned. Conclusion. Significant increases in movements of the fibula relative to the tibia occur when an external rotation torque is provided. However, axial pressure seemed to limit external rotation because of the bony congruence of the tibiotalar surface. The AITFL is necessary to prevent the fibula to rotate externally when the foot is rotating externally. The deltoid ligament is the main stabilizer of the ankle mortise

Ankle fractures are among the most common types of fractures. If surgery is not performed within 12 to 24 hours, ankle swelling is likely to develop and delay the operative fixation. This leads to patients staying longer in the ward waiting and increased hospital occupancy. This prolonged stay has significant financial implication as well as it is frustrating for both patients and health care professionals. The aim was to formulate a pathway for the ankle fracture patients coming to the emergency department, outpatients and planned for operative intervention. To identify whether pre-operative hospital admissions of stable ankle fracture patients are reduced with the implementation of the pathway. We formulated an ankle fracture fixation pathway, which was approved for use in December 2020. A retrospective analysis of 6 months hospital admissions of ankle fracture patients in the period between January to June 2020. The duration from admission to the actual surgery was collected to review if some admissions could have been avoided and patients brought directly on the surgery day. A total of 23 patients were included. Mean age was 60.5 years and SD was 17years. 94% of patients were females. 10 patients were appropriately discharged.7 Patients were appropriately admitted. 6 Patients were unnecessarily admitted. These 6 patients were admitted on presentation to ED. Retrospective analysis of this audit showed that this cohort of patients met the safe discharge criteria and could have been discharged. Duration of unnecessary stay ranged from 1 to 11 days (21 days in total). Total saving could have been £6300. Standards were met in 74% of cases. Preoperative hospital admission could be reduced with the proposed pathway. It is a valuable tool to be used and should be implemented to reduce unnecessary hospital admissions

Background. Supination-external rotation (SER) injuries make up 80% of all ankle fractures. SER stage 2 injuries (AITFL and Weber B) are considered stable. SER stage 3 injury includes disruption of the posterior malleolus (or PITFL). In SER stage 4 there is either medial malleolus fracture or deltoid injury too. SER 4 injuries have been considered unstable, requiring surgery. The deltoid ligament is a key component of ankle stability, but clinical tests to assess deltoid injury have low specificity. This study specifically investigates the role of the components of the deep deltoid ligament in SER ankle fractures. Aim. To investigate the effect of deep deltoid ligament injury on SER ankle fracture stability. Methods. Four matched pairs (8 specimens) were tested using a standardised protocol. Specimens were sequentially tested for stability when axially loaded with a custom rig with up to 750N. Specimens were tested with: ankle intact; lateral injury (AITFL and Weber B); additional posterior injury (PITFL); additional anterior deep deltoid; additional posterior deep deltoid; lateral side ORIF. Clinical photographs and radiographs were recorded. In addition, dynamic stress radiographs were performed after sectioning the deep deltoid and then after fracture fixation to assess tilt of the talus in eversion. Results. All specimens with an intact posterior deep deltoid ligament were stable when loaded and showed no talar tilt on dynamic assessment. Once the posterior deep deltoid ligament was sectioned there was instability in all specimens. Surgical stabilisation of the lateral side prevented talar shift but not talar tilt. Conclusion. If the posterior deep deltoid ligament is intact SER fractures may be managed without surgery in a plantigrade cast. Without immobilisation the talus may tilt, risking deltoid incompetence