Background. Back pain is a common orthopaedic problem which results in hospital admissions in severe cases. The aim of our study was to identify the reasons for back pain admissions and role of further investigations in the treatment of severe back pain. Methods. We collected data prospectively for all admissions between January and March 2011. Demographic details were recorded along with the reasons for admissions, time of admission, further investigations and treatment offered. Results. Total admissions were 850 and 58 (6.8%) had severe back pain.13 patients (22%) had fractures (Group-A); 16 patients (27%) did not require MRI scan (Group-B); 27 patients (50%) needed MRI scan of the lumbosacral spine (Group-C). The mean age of Group-A was 67 years (15–93). 3 were male and 10 females. 10 patients had lumbar and 3 had thoracic spine fractures. The mean age of Group-B was 59 years (32–87). 8 were male and 8 females. The mean age of Group-C was 47 years (23–79). 9 were male and 18 females. The mean hospital stay for Group-C was 5days (0–29). 16 patients (59%) were referred by GP, 5(18%) by emergency department and 3(11%) by physiotherapist. 9(43%) were admitted for pain control, 8(38%) with suspected Cauda Equina syndrome and 2(9%) for further investigations. 20 patients (83%) were admitted during the day, 3(12%) in the evening and 1(4%) during the night. No patient had Cauda equina syndrome on clinical and radiological examination. 12 patients(44%) had nerve root compression on the MRI scan and 7(58%) were offered surgery. Conclusions. Patients were older in group-A with a mean age of 67 years. 27% did not require MRI scan. 67% females admitted with back pain required an MRI scan. No patient had Cauda Equina Syndrome. 55% patients had no nerve root compression. MRI scan was performed to reassure the patients and clinicians with negative results in the presence of severe back pain and unclear neurological signs. Conflicts of interest. None. Sources of funding. None

Purpose and background. Whether to order an MRI scan or not for patients with low back and leg pain (LBP). Resources are limited. Waiting for diagnostic imaging impacts time to treatment and may be critical to the “18 week target”. We have looked into devising a system in which we can ordered MRI scans for patients with LBP pre-clinical assessment based on questionnaire and accessing their referral letter. Methods and results. 49 patient's referrals were looked into (randomly picked). 23 had a questionnaire filled by either themselves or their GPs. the rests had MRI scans ordered based on their referral letters. MRI scans were requested pre-clinical assessment for patients with symptoms spreading beyond their knees and willing to consider interventional treatments (injections or operations). We considered MRI positive if the report mentioned stenosis or disc prolapse causing nerve root or cauda compression. 7 out of the 23 fitted the criteria for MRI. 6 (85%) of them had positive results. 26 of the GP referrals letters had MRI out of those 16 (61%) had positive results. In total out of 33 MRI, 22 (66.7%) were positive. Conclusion. Our study showed that pre-clinic MRI scanning for patients with LBP is an effective method to find surgically treatable pathology. Using the questionnaire was more advantageous than the referral letter in order to identify patients who would benefit from pre-clinic MRI scanning. With the small numbers this is not statistically significant. We propose that rather than a blanket scanning, it would be reasonable to scan patients based on their referral letter. No Conflict of interest. No funding obtained. This abstract has not been previously published in whole or substantial part nor has it been presented previously at a national meeting

Aims and objectives. Our aim was to evaluate the indications for patients undergoing magnetic resonance imaging (MRI) of the knee prior to referral to an orthopaedic specialist, and ascertain whether these scans altered initial management. Materials and Method. We retrospectively reviewed all referrals received by a single specialist knee surgeon over a 1-year period. Patient demographics, relevant history, examination findings and past surgical procedures were documented. Patients having undergone MRI prior to referral were identified and indications for the scans recorded. These were reviewed against The NHS guidelines for Primary Care Physicians to identify if the imaging performed was appropriate in each case. Results. A total of 261 patients were referred between 1. st. July 2018 and 30. th. June 2019. 87/261 patients underwent MRI of the knee joint prior to referral. The mean patient age was 53 years with predominance of male patients (52 verses 35 females). 21/87 patients (24%) underwent the appropriate imaging prior to referral with only 13% of patients undergoing x-ray imaging before their MRI. In cases where MRI was not indicated, patients waited an average of 12 weeks between their scan and a referral being sent to the specialist knee surgeon. Conclusion. 76% of patients referred to orthopaedics had inappropriate MRI imaging arranged by their primary care physician. For a single consultant's referrals over 1 year these unnecessary MRI scans cost the NHS £13,200. Closer adherence to the guidelines by primary care physicians would result in a financial saving for the NHS, faster referral times and a more effective use of NHS resources

In spite of extensive accounts describing the blood supply to the femoral head, the prediction of avascular necrosis is elusive. Current opinion emphasises the contributions of the superior retinacular artery but may not explain the clinical outcome in many situations, including intramedullary nailing of the femur and resurfacing of the hip. We considered that significant additional contribution to the vascularity of the femoral head may exist. A total of 14 fresh-frozen hips were dissected and the medial circumflex femoral artery was cannulated in the femoral triangle. On the test side, this vessel was ligated, with the femoral head receiving its blood supply from the inferior vincular artery alone. Gadolinium contrast-enhanced MRI was then performed simultaneously on both control and test specimens. Polyurethane was injected, and gross dissection of the specimens was performed to confirm the extraosseous anatomy and the injection of contrast. The inferior vincular artery was found in every specimen and had a significant contribution to the vascularity of the femoral head. The head was divided into four quadrants: medial (0), superior (1), lateral (2) and inferior (3). In our study specimens the inferior vincular artery contributed a mean of 56% (25% to 90%) of blood flow in quadrant 0, 34% (14% to 80%) of quadrant 1, 37% (18% to 48%) of quadrant 2 and 68% (20% to 98%) in quadrant 3. Extensive intra-osseous anastomoses existed between the superior retinacular arteries, the inferior vincular artery and the subfoveal plexus.

Biplane video X-ray (BVX) – with models segmented from magnetic resonance imaging (MRI) – is used to directly track bones during dynamic activities. Investigating tibiofemoral kinematics helps to understand effects of disease, injury, and possible interventions. Develop a protocol and compare in-vivo kinematics during loaded dynamic activities using BVX and MRI. BVX (60 FPS) was captured whilst three healthy volunteers performed three repeats of lunge, stair ascent and gait. MRI scans were performed (Magnetom 3T Prisma, Siemens). 3D bone models of the tibia and femur were segmented (Simpleware Scan IP, Synopsis). Bone poses were obtained by manually matching bone models to X-rays (DSX Suite, C-Motion Inc.). Mean range of motion (ROM) of the contact points on the medial and lateral tibial plateau were calculated using custom MATLAB code (MathWorks). Results were filtered using an adaptive low pass Butterworth filter (Frequency range: 5-29Hz). Gait and Stair ascent activities from one participant's data showed increased ROM for medial-lateral (ML) translation in the medial compartment but decreased ROM in anterior-posterior (AP) translation when comparing against the same translations on the lateral compartment of the tibial plateau. Lunge activity showed increased ROM for both ML and AP translation in the medial compartment when compared with the lateral compartment. These results highlight the variability in condylar translations between different activities. Understanding healthy in-vivo kinematics across different activities allows the determination of suitable activities to best investigate the kinematic changes due to disease or injury and assess the efficacy of different interventions. Acknowledgements: This research was supported by the Engineering and Physical Sciences Research Council (EPSRC) doctoral training grant (EP/T517951/1)

Partial meniscectomy patients have a greater likelihood for the development of early osteoarthritis (OA). To prevent the onset of early OA, patient-specific treatment algorithms need to be created that predict patient risk to early OA after meniscectomy. The aim of this work was to identify patient-specific risk factors in partial meniscectomy patients that could potentially lead to early OA. Partial meniscectomy patients operated between 01/2017 and 12/2019 were evaluated in the study (n=317). Exclusion criteria were other pathologies or surgeries for the evaluated knee and meniscus (n = 114). Following informed consent, an online questionnaire containing demographics and the “Knee Injury and Osteoarthritis Outcome Score” (KOOS) questionnaire was sent to the patient. Based on the KOOS pain score, patients were classified into “low” (> 75) and “high” (< 75) risk patients, indicating risk to symptomatic OA. The “high risk” patients also underwent a follow-up including an MRI scan to understand whether they have developed early OA. From 203 participants, 96 patients responded to the questionnaire (116 did not respond) with 61 patients considered “low-risk” and 35 “high-risk” patients. Groups that showed a significant increased risk for OA were patients aged > 40 years, females, overweight (BMI >25 kg/m2 ≤ 30 kg/m2), and smokers (*p < 0.05). The “high-risk”-follow-up revealed a progression of early osteoarthritic cartilage changes in seven patients, with the remaining nineteen patients showing no changes in cartilage status or pain since time of operation. Additionally, eighteen patients in the high-risk group showed a varus or valgus axis deviation. Patient-specific factors for worse postoperative outcomes after partial meniscectomy and indicators for an “early OA” development were identified, providing the basis for a patient-specific treatment approach. Further analysis in a multicentre study and computational analysis of MRI scans is ongoing to develop a patient-specific treatment algorithm for meniscectomy patients

Recent studies on animal models focused on the effect of preserving tendon remnant of rotator cuff on tendon healing. A positive effect by combining tendon remnant preservation and small bone vents on the greater tuberosity in comparison with standard tendon-to-bone repair has been shown. The purpose of the present clinical study was to evaluate the efficacy of biologic augmentation of arthroscopic rotator cuff repair by maintaining tendon remnant on rotator cuff footprint combined with small bone vents of the greater tuberosity. A retrospective study was conducted. All patients who underwent arthroscopic rotator cuff repair associated with small bone vents (nanofractures) and tendon footprint preservation were considered eligible for the study. Inclusion criteria were: diagnosis of full-thickness rotator cuff tear as diagnosed at preoperative magnetic resonance imaging (MRI) and confirmed at the time of surgery; minimum 24-month of follow-up and availability of post-operative MRI performed not earlier than 6 months after surgery. Exclusion criteria were: partial thickness tears, irreparable tears, capsulo-labral pathologies, calcific tendonitis, gleno-humeral osteoarthritis and/or previous surgery. Primary outcome was the ASES score. Secondary outcomes were: Quick-DASH and WORC scores, and structural integrity of repaired tendons by magnetic resonance imaging (MRI) performed six months after surgery. A paired t-test was used to compare pre- and postoperative clinical outcomes. Subgroup analysis was performed according to tear size. Significance was set at p < 0.05. The study included 29 patients (M:F = 15:14). Mean age (+ SD) of patients was 61.7 + 8.9 years. Mean follow-up was 27.4 ± 2.3 months. Comparison between pre- and postoperative functional scores showed significant clinical improvement (p < 0.001). Subgroup analysis for tear size showed significant differences in the QuickDASH score (0.04). Particularly, a significant difference in the QuickDASH score could be detected between medium and large tears (p=0.008) as well as medium and massive lesions (p=0.04). No differences could be detected between large and massive tears (p= 0.35). Postoperative imaging showed healed tendons in 21 out of 29 (72%) cases. Preservation of tendon remnant combined with small bone vents in the repair of medium-to-massive full-thickness rotator cuff tears provided significant improvement in clinical outcome compared to baseline conditions with complete structural integrity in 72% of the cases

Abstract. Objectives. Magnetic resonance imaging (MRI) is one of the most widely used investigations for knee pain as it provides detailed assessment of the bone and soft tissues. The aim of this study was to report the frequency of each diagnosis identified on MRI scans of the knee and explore the relationship between MRI results and onward treatment. Methods. Consecutive MRI reports from a large NHS trust performed in 2017 were included in this study. The hospital electronic system was consulted to identify whether a patient underwent x-ray prior to the MRI, attended an outpatient appointment or underwent surgery. Results. 4466 MRI knees were performed in 2017 with 71.2% requested in primary care and 28.1% requested in secondary care. The most common diagnosis was signs of arthritis (55.2%), followed by meniscal tears (42.8%) and ACL tears (8.3%). 49.4% of patients who had an MRI attended outpatients and 15.6% underwent surgery. The rate of knee surgery was significantly higher for patients who had their scans requested in secondary care (32.9% vs 8.9%, p < 0.001). Conclusion. The rate of surgical intervention following MRI is low and given these results it seems unlikely that the scan changes practice in most cases. The rate of surgery and outpatient follow up was significantly higher in scans requested by secondary care. We urge clinicians avoid wasteful use of MRI and recommend the use of plain radiography prior to MRI where arthritis may be present

Several studies have evaluated the risk of peroneal nerve (PN) injuries in all-inside lateral meniscal repair using standard knee magnetic resonance imaging (MRI) with the 30 degrees flexed knee position which is different from the knee position during actual arthroscopic lateral meniscal repair. The point of concern is “Can the risk of PN injury using standard knee MRIs be accurately determined”. To evaluate and compare the risk of PN injury in all-inside lateral meniscal repair in relation to both borders of the popliteus tendon (PT) using MRIs of the two knee positions in the same patients. Using axial MRI studies with standard knee MRIs and figure-of-4 with joint fluid dilatation actual arthroscopic lateral meniscal repair position MRIs, direct lines were drawn simulating a straight all-inside meniscal repair device from the anteromedial and anterolateral portals to the medial and lateral borders of the PT. The distance from the tip of each line to the PN was measured. If a line touched or passed the PN, a potential risk of iatrogenic injury was noted and a new line was drawn from the same portal to the border of the PN. The danger area was measured from the first line to the new direct line along the joint capsule. In 28 adult patients, the closest distances from each line to the PN in standard knee MRI images were significantly shorter than arthroscopic position MRI images (all p-values < 0.05). All danger areas assessed in the actual arthroscopic position MRIs were included within the danger areas as assessed by the standard knee MRIs. We found that the standard knee MRIs can be used to determine the risk of peroneal nerve injury in arthroscopic lateral meniscal repair, although the risks are slightly overestimated

Cervical spine facet tropism (CFT) defined as the facets’ joints angles difference between right and left sides of more than 7 degrees. This study aims to investigate the relationship between cervical sagittal alignment parameters and cervical spine facets’ tropism. A retrospective cross-sectional study carried out in a tertiary center where cervical spine magnetic resonance imaging (MRI) radiographs of patients in orthopedics/spine clincs were included. They had no history of spine fractures. Images’ reports were reviewed to exclude those with tumors in the c-spine. A total of 96 patients was included with 63% of them were females. The mean of age was 45.53± 12.82. C2-C7 cobb's angle (CA) and C2-C7 sagittal vertical axis (SVA) means were −2.85±10.68 and 1.51± 0.79, respectively. Facet tropism was found in 98% of the sample in at least one level on either axial or sagittal plane. Axial C 2–3 CFT and sagittal C4-5 were correlated with CA (r=0.246, P 0.043, r= −278, P 0.022), respectively. In addition, C2-C7 sagittal vertical axis (SVA) was moderately correlated with axial c2-3 FT (r= −0.330, P 0.006) Also, several significant correlations were detected in our model Cervical vertebral slopes and CFT at the related level. Nonetheless, high BMI was associated with multi-level and multiplane CFT with higher odd's ratios at the lower levels. This study shows that CFT at higher levels is correlated with increasing CA and decreasing SVA and at lower levels with decreasing CA. Obesity is a risk factor for CFT

In an attempt to alleviate symptoms of the disease, patients with knee osteoarthrosis (KOA) frequently alter their gait patterns. Understanding the underlying pathomechanics and identifying KOA phenotypes is essential for improving treatments. We aimed to investigate altered kinematics in patients with KOA to identify subgroups. Sixty-six patients with symptomatic KOA scheduled for total knee arthroplasty and 12 age-matched healthy volunteers with asymptomatic knees were included. We used k-means to separate the patients based on dynamic radiostereometric assessed knee kinematics. Ligament lesions, KOA score, and clinical outcome were assessed by magnetic resonance imaging, radiographs, and patient reported outcome measures, respectively. We identified four clusters that were supported by clinical characteristics. Compared with the healthy group; The flexion group (n=20): revealed increased flexion, greater adduction, and joint narrowing and consisted primarily of patients with medial KOA. The abduction group (n=17): revealed greater abduction, joint narrowing and included primarily patients with lateral KOA. The anterior draw group (n=10): revealed greater anterior draw, external tibial rotation, lateral tibial shift, adduction, and joint narrowing. This group was composed of patients with medial KOA, some degree of anterior cruciate ligament lesion and the greatest KOA score. The external rotation group (n=19): revealed greater external tibial rotation, lateral tibial shift, adduction, and joint narrowing while no anterior draw was observed. This group included primarily patients with medial collateral and posterior cruciate ligament lesions. Patients with KOA can, based on their gait patterns, be classified into four subgroups, which relate to their clinical characteristics. The findings add to our understanding of associations between disease pathology characteristics in the knee and the pathomechanics in patients with KOA. A next step is to investigate if patients in the pathomechanic clusters have different outcomes following total knee arthroplasty

One-fourth of all ankle trauma involve injury to the syndesmotic ankle complex, which may lead to syndesmotic instability and/or posttraumatic ankle osteoarthritis in the long term if left untreated. The diagnosis of these injuries still poses a deceitful challenge, as MRI scans lack physiologic weightbearing and plain weightbearing radiographs are subject to beam rotation and lack 3D information. Weightbearing cone-beam CT (WBCT) overcomes these challenges by imaging both ankles during bipedal stance, but ongoingdebate remains whether these should be taken under weightbearing conditions and/or during application of external rotation stress. The aim of this study is study therefore to compare both conditions in the assessment of syndesmotic ankle injuries using WBCT imaging combined with 3D measurement techniques. In this retrospective study, 21 patients with an acute ankle injury were analyzed using a WBCT. Patients with confirmed syndesmotic ligament injury on MRI were included, while fracture associated syndesmotic injuries were excluded. WBCT imaging was performed in weightbearing and combined weightbearing-external rotation. In the latter, the patient was asked to internally rotate the shin until pain (VAS>8/10) or a maximal range of motion was encountered. 3D models were developed from the CT slices, whereafter. The following 3D measurements were calculated using a custom-made Matlab® script; Anterior tibiofibular distance (AFTD), Alpha angle, posterior Tibiofibular distance (PFTD) and Talar rotation (TR) in comparison to the contralateral non-injured ankle. The difference in neutral-stressed Alpha angle and AFTD were significant between patients with a syndesmotic ankle lesion and contralateral control (P=0.046 and P=0.039, respectively). There was no significant difference in neutral-stressed PFTD and TR angle. Combined weightbearing-external rotation during CT scanning revealed an increased AFTD in patients with syndesmotic ligament injuries. Based on this study, application of external rotation during WBCT scans could enhance the diagnostic accuracy of subtle syndesmotic instability

Knee pain is common, representing a significant socioeconomic burden. Caused by a variety of pathologies, its evaluation in primary-care is challenging. Subsequently, an over-reliance on magnetic resonance imaging (MRI) exists. Prior to orthopaedic surgeon referral, many patients receive no, or incorrect, imaging. Electronic-triage (e-triage) tools represent an innovative solution to address this problem. The primary aim of this study was to ascertain whether an e-triage tool is capable of outperforming existing clinical pathways to determine the correct pre-hospital imaging based on knee pain diagnosis. Patients ≥18 years with a new presentation of knee pain were retrospectively identified. The timing and appropriateness of imaging was assessed. A symptom-based e-triage tool was developed, using the Amazon LEXbotplatform, and piloted to predict five common knee pathologies and suggest appropriate imaging. 1462 patients were identified. 17% of arthroplasty patients received an ‘unnecessary MRI’, whilst 28% of arthroscopy patients did not have a ‘necessary MRI’, thus requiring a follow-up appointment, with a mean delay of three months (SD 2.6, range 0.2-20.2). Using NHS tariffs, a wasted cost through unnecessary/necessary MRIs and subsequent follow-up appointments was estimated at £45,816. The e-triage pilot was trialled with 41 patients (mean age:58.4 years, 58.5% female). Preliminary diagnoses were available for 34 patients. Using the highest proportion of reported symptoms in the corresponding group, the e-triage tool correctly identified three of the four knee pathologies. The e-triage tool did not correctly identify anterior cruciate ligament injuries (n=3). 79.2% of participants would use the tool again. A significant number of knee pathology patients received incorrect imaging prior to their initial hospital appointment, incurring delays and unnecessary costs. A symptom-based e-triage tool was developed, with promising pilot data and user feedback. With refinement, this tool has the potential to improve wait-times and referral quality, whilst reducing costs

A Morel-Lavallee lesion (MLL) is a benign cystic lesion that occurs due to injury to the soft-tissue envelope's perforating vascular and lymphatic systems, resulting in a distinctive hemolymphatic fluid accumulation between the tissue layers. The MLL has the potential to make a significant impact on the treatment of orthopaedic injuries. A 79-year-old male patient community ambulatory with assisting aid (cane) known case of Diabetes mellitus, hypertension, bronchial asthma and ischemic heart disease. He was brought to the Emergency, complaining of right hip discomfort and burning sensation for the last 5 days with no history of recent trauma at all. Patient had history of right trochanteric femur fracture 3 years ago, treated with DHS in a privet service. Clinical and Radiological assessment showed that the patient mostly has acute MLL due to lag screw cut out. We offered the patient the surgical intervention, but he refused despite explaining the risks of complications if not treated and preferred to receive the conservative treatment. Compression therapy management explained to him including biker's shorts (instructed to be worn full-time a day) and regular follow up in clinic. Symptom's improvement was reported by the patient in the subsequent visits. In the polytrauma patient, a delayed diagnosis of these lesions is conceivable due to the presence of more visible injuries. It's located over the greater trochanter more commonly, but sometimes in other areas such as the lower lumbar region, the thigh, or the calf. Incorrect or delayed diagnosis and care can have unfavorable outcomes such as infection, pseudocyst development, and cosmetologically deformity. Magnetic resonance imaging (MRI) and ultrasound will aid in MLL diagnosis. However, the effectiveness of MLL therapy remains debatable. We strongly believe that the MLL caused due to tangential shear forces applied to the soft tissue leads to accumulation of the blood and/or lymph between the subcutaneous and overlying fascia and it often misdiagnosed due to other distracting injuries. Nontheless, in our case we reported MLL occur due to internal pressure on the fascia caused by cut out of DHS lag screw

Meniscal injuries affect over 1.5 million people across Europe and the USA annually. Injury greatly reduces knee joint mobility and quality of life and frequently leads to the development of osteoarthritis. Tissue engineered strategies have emerged in response to a lack of viable treatments for meniscal pathologies. However, to date, constructs mimicking the structural and functional organisation of native tissue, whilst promoting deposition of new extracellular matrix, remains a bottleneck in meniscal repair. 3D bioprinting allows for deposition and patterning of biological materials with high spatial resolution. This project aims to develop a biomimetic 3D bioprinted meniscal substitute. Meniscal tissue was characterised to effectively inform the design of biomaterials for bioprinting constructs with appropriate structural and functional properties. Histology, gene expression and mass spectrometry were performed on native tissue to investigate tissue architecture, matrix components, cell populations and protein expression regionally across the meniscus. 3D laser scanning and magnetic resonance imaging were employed to acquire the external geometrical information prior to fabrication of a 3D printed meniscus. Bioink suitability was investigated through regional meniscal cell encapsulation in blended hydrogels, with the incorporation of growth factors and assessed for their suitability through rheology, scanning electron microscopy, histology and gene expression analysis. Meniscal tissue characterisation revealed regional variations in matrix compositions, cellular populations and protein expression. The process of imaging through to 3D printing highlighted the capability of producing a construct that accurately replicated meniscal geometries. Regional meniscal cell encapsulation into hydrogels revealed a recovery in cell phenotype, with the incorporation of growth factors into the bioink's stimulating cellular re-differentiation and improved zonal functionality. Meniscus biofabrication highlights the potential to print patient specific, customisable meniscal implants. Achieving zonally distinct variations in cell and matrix deposition highlights the ability to fabricate a highly complex tissue engineered construct. Acknowledgements: This work was undertaken as part of the UK Research and Innovation (UKRI)-funded CDT in Advanced Biomedical Materials

It is known that the gait dynamics of elderly substantially differs from that of young people. However, it has not been well studied how this age-related gait dynamics affects the knee biomechanics, e.g., cartilage mechanical response. In this study, we investigated how aging affects knee biomechanics in a female population using subject-specific computational models. Two female subjects (ages of 23 and 69) with no musculoskeletal disorders were recruited. Korea National Institute for Bioethics Policy Review Board approved the study. Participants walked at a self-selected speed (SWS), 110% of SWS, and 120% of SWS on 10 m flat ground. Three-dimensional marker trajectories and ground reaction forces (Motion Analysis, USA), and lower limbs’ muscle activities were measured (EMG, Noraxon USA). Knee cartilage and menisci geometries were obtained from subjects’ magnetic resonance images (3T, GE Health Care). An EMG-assisted musculoskeletal finite element modeling workflow was used to estimate knee cartilage tissue mechanics in walking trials. Knee cartilage and menisci were modeled using a transversely isotropic poroviscoelastic material model. Walking speed in SWS, 110%, and 120% of SWS were 1.38 m/s, 1.51 m/s, and 1.65 m/s for the young, and 1.21 m/s, 1.34 m/s and 1.46 m/s for the elderly, respectively. The maximum tensile stress in the elderly tibial cartilage was ~25%, ~33%, and ~32% lower than the young at SWS, 110%, and 120% of SWS, respectively. These preliminary results suggest that the cartilage in the elderly may not have enough stimulation even at 20% increases in walking speed, which may be one reason for tissue degeneration. To enhance these findings, further study with more subjects and different genders will investigate how age-related gait dynamics affects knee biomechanics. Acknowledgments: Australian NHMRC Ideas Grant (APP2001734), KITECH (JE220006)

Anterior cruciate ligament reconstruction (ACLR) using a semitendinosus (ST) autograft, with or without gracilis (GR), results in donor muscle atrophy and varied tendon regeneration. The effects of harvesting these muscles on muscle moment arm and torque generating capacity have not been well described. This study aimed to determine between-limb differences (ACLR vs uninjured contralateral) in muscle moment arm and torque generating capacity across a full range of hip and knee motions. A secondary analysis of magnetic resonance imaging was undertaken from 8 individuals with unilateral history of ST-GR ACLR with complete ST tendon regeneration. All hamstring muscles and ST tendons were manually segmented. Muscle length (cm), peak cross-sectional area (CSA) (cm. 2. ), and volume (cm. 3. ) were measured in ACLR and uninjured contralateral limbs. OpenSim was used to simulate and evaluate the mechanical consequences of changes in normalised moment arm (m) and torque generating capacity (N.m) between ACLR and uninjured contralateral limbs. Compared to uninjured contralateral limbs, regenerated ST tendon re-insertion varied proximal (+) (mean = 0.66cm, maximum = 3.44cm, minimum = −2.17cm, range = 5.61cm) and posterior (+) (mean = 0.38cm maximum = 0.71cm, minimum = 0.02cm, range = 0.69cm) locations relative to native anatomical positions. Compared to uninjured contralateral limbs, change in ST tendon insertion point in ACLR limbs resulted in 2.5% loss in peak moment arm and a 3.4% loss in peak torque generating capacity. Accounting for changes to both max isometric force and ST moment arm, the ST had a 14.8% loss in peak torque generating capacity. There are significant deficits in ST muscle morphology and insertion points following ST-GR ACLR. The ST atrophy and insertion point migration following ACLR may affect force transmission and distribution within the hamstrings and contribute to persistent deficits in knee flexor and internal rotator strength

In current practice in the UK there are three main approaches to investigating suspected scaphoid fractures not seen on initial plain film x-rays. Early MRI of all cases. Review all cases in clinic at two weeks with repeat x-rays. Hybrid model. Virtual Fracture Clinic (VFC) triage to reduce those who are seen in clinic at two weeks by:. ∘. Organising early MRI for those with high-risk presentation. ∘. Discharging those with an alternative more likely diagnosis. Our unit uses the VFC model. We aimed to evaluate its efficiency, safety, clinical outcomes and economic viability. All patients attending the emergency department with either a confirmed or suspected scaphoid fracture between March and December 2020 were included (n=305). Of these 297 were referred to the VFC: 33 had a confirmed fracture on x-ray and 264 had a suspected fracture. Of the suspected fractures reviewed in VFC 14% had an MRI organised directly owing to a high-risk presentation, 79% were brought for fracture clinic review and 17% discharged with an alternative diagnosis such as osteoarthritis. Of those subsequently reviewed in fracture clinic at two weeks: 9% were treated as scaphoid fractures (based on clinical suspicion and repeat x-rays), 17% had MRI or CT imaging organised, 5% did not attend and 69% were discharged. Overall, 17% of cases initially triaged, had further imaging – 41 MRIs and 5 CTs. MRI detected: 5% scaphoid fracture, 17% other fracture, 24% bone contusion, complete ligament tear 10%, partial ligament tear 39% and normal study 10%. The results of MRI minimally affected management. 3 patients were taken out of plaster early, 1 patient was immobilized who was not previously and no patients underwent operative management. In the following 12-month period one patient re-presented with a hand or wrist issue. This approach avoided 218 MRIs, equating to £24000 and 109 hours of scanner time. VFC triage and selective use of MRI scanning is a safe, efficient and cost-effective method for the management suspected scaphoid fractures. This can be implemented in units without the resource to MRI all suspected scaphoid fractures from the emergency department

Distal radius fractures are common, particularly in post-menopausal women. Several factors have been identified such as osteopenia and an increased risk of falling. We hypothesised that increased soft tissue padding from muscle and fat in the volar hand may confer an element of protection against fractures more in men than women and more in younger than older patients. The aim of the study was to assess for thenar and hypothenar thickness and assess whether it varies between sexes and changes with age. We retrospectively evaluated hand MRI scans performed for non-acute conditions in adults without previous injury or surgery. Using the Patient Archiving and Communication System (PACS) we measured the distance (mm) from the volar surface of the trapezium to the skin, the hook of the hamate to skin and the pisiform to skin as measures of thenar and hypothenar thickness. We also recorded the sex and age of the subjects. Soft tissue thickness was corrected for hand size by dividing by capitate length which we measured; we have already established this as a surrogate measure of hand size. The scans of 51 men (mean age 35, range 19–66) years and 27 women (mean age 49, range 19–79) years were reviewed. Men had significantly thicker soft tissues compared to women over both the thenar and hypothenar eminences (p=0.0001). Soft tissue thickness did not change significantly with age (p> 0.05). The study confirms a significant difference in volar hand soft tissue thickness between men and women accounting for differences in hand size. Our previous research has shown how we fall onto our outstretched hands in the upper limb falling reflex and we have shown that padding the thenar and hypothenar eminences reduces force transmission to the forearm bones. In theory thicker thenar and hypothenar musculature would help protect against distal radius fractures following a fall on an outstretched hand. The thinner musculature on women may further predispose them to an increased risk of distal radius fractures. Further research is needed to assess for any loss of volar hand soft tissue thickness beyond age 75 years