bluuebunny/crossref_metadata_2025 huggingface dataset:
Does switching from tobacco to reduced-risk products free up hospital resources?
Authors: Moscone Francesco
Published: August 2023

Promoting a shift from smoking tobacco to reduced-risk products—such as vapes and heat-not-burn tobacco—has the potential to ease the burden on healthcare resources, particularly health expenditure, if empirical evidence shows that reduced-risk products are an effective smoking cessation tool or can help to mitigate the risk of disease. However, there are notable variations in needs and provision of healthcare services between different regions. This article will explore this heterogeneity with the aim of understanding the different health impacts of switching from smoking to reduced-risk products across England, assessing the potential savings for the NHS and potential progress towards the goal of the country becoming smoke-free. This exploratory analysis of different sources of variation across regions offers policy insights to motivate further research.
Dietary hyperthyroidism in a dog with epileptic seizures
Authors: Foreman Max
Published: August 2023

This report discusses a case of suspected dietary hyperthyroidism in a 2-year-old male crossbreed dog. The dog presented with a history of tonic-clonic seizures, seen over the previous 6 months, and was refractory to increasing doses of phenobarbitone. Serum total thyroxine concentrations were persistently elevated on repeated sampling; the rest of the investigations were normal. The initial diet – a raw food diet – was tested and found to contain detectable levels of total thyroxine. Dietary hyperthyroidism was therefore proposed as a potential cause of seizures in this case.
EARLY TIBIAL SUBSIDENCE OF THE CEMENTLESS OXFORD UNICOMPARTMENTAL KNEE ARTHROPLASTY
Authors: Arthur Lachlan , Amin Ali , Rahman Azmi , Tu Shihfan Jack , Mellon Stephen , Murray David
Published: August 2023

Introduction

Anecdotal reports suggest some cementless Oxford Unicompartmental Knee Replacements (OUKRs) have painful early subsidence of the tibial component with valgus rotation and/or posterior tilting. The incidence of subsidence and its association with pain is poorly understood. This radiographic study aimed to evaluate the incidence of tibial subsidence and five-year patient reported outcome measures (PROMs) of a cementless OUKR cohort.

Methodology

Cementless OUKRs from a high-volume centre with acceptable post-operative and five-year radiographs were included. Subsidence was determined by measuring the angle of the tibial tray/tibial axis angle and distance between the tibial tray axis and fibula head on anteroposterior and lateral radiographs using a custom MATLAB program. Analysis of 5-year PROMs assessed the relationship between subsidence and pain. Radiographs indicating tibial subsidence were validated by two observers.

Results

Radiographs of 94 cementless OUKRs were analysed of which five tibial components had subsided (incidence=5%) with an average of 1.92° varus rotation and 2.97° posterior tilt. Subsidence appeared to occur within the first post-operative year with all tibial components fixed securely at 5 years. Two subsiders had moderate pain (ICOAP=20.5,15.9, AKSS Pain=20,45) and lower Oxford Knee Scores (OKS=26,31) compared to the cohort means (ICOAP=3.91, AKSS Pain=45.9, OKS = 43.6). These two subsiders had BMIs greater than 30.

Conclusion

This study found 5% of cementless OUKRs in the cohort underwent tibial subsidence. Subsidence with moderate pain occurred in 2% of cases, and pain may be associated with obesity. A larger study is needed to study subsidence in greater detail.
MEDIAL UNICOMPARTMENTAL KNEE ARTHROPLASTY: BENEFITS AND RISKS OF SIMULTANEOUS BILATERAL KNEE SURGERY
Authors: Petsiou Dioni , Nicholls Kate , Wilcocks Katharine , Matthews Andrew , Vachtsevanos Leonidas
Published: August 2023

Introduction

In patients with bilateral unicompartmental knee osteoarthritis, simultaneous bilateral surgery is cost effective, with both patient-specific and wider socioeconomic benefits. There are concerns however regarding higher complication rates with bilateral knee surgery. This study compares simultaneous bilateral unicompartmental knee arthroplasty (UKA), to single side UKA in terms of complications and outcomes.

Methodology

This is a retrospective case-control study of single side medial UKA patients (controls) and simultaneous bilateral medial UKA patients (cases). All patients underwent surgery between 2018 and 2022 by a single surgeon. The two cohorts were compared for perioperative blood loss (PBL), length of stay (LOS), complications (infections, blood clots, wound problems), Oxford Knee Score improvement (OKS) and revision surgery, with a follow-up period of up to 5 years.

Results

64 patients were followed up comprising 55 controls and 9 cases. Average length of stay for controls was 1.55 days and 2.22 days for cases (p=0.03). Average haemoglobin drop was 7.5g/l in controls and 12.8g/l in cases (p=0.04). The OKS improvement was comparable in both groups (p=0.95) with no complications and no revision surgery in either group.

Conclusion

The statistically significant differences in PBL and LOS were not clinically relevant. There were no blood transfusions and postoperative haemoglobin was within normal range in more than 60% of cases. Simultaneous bilateral unicompartmental knee arthroplasty is a financially favourable and safe option for patients with bilateral knee medial unicompartmental osteoarthritis.
SURVIVAL OF CEMENT-LINKED CUSTOM IMPLANTS AND THEIR MEDIUM-TERM OUTCOMES SUPPORT THEIR USE IN COMPLEX AND SALVAGE ARTHROPLASTY
Authors: Ali Asad , Ahmed Iftikaar , Shearman Alexander , McCulloch Robert
Published: August 2023

Introduction

Patients presenting with loosening or a fracture between ipsilateral hip and knee replacements provide a unique reconstructive challenge. We present mid-term results of the cement-over megaprosthesis (COM) when managing these complex cases. A COM is cement-linked to the stem of a well-fixed existing implant. We report the largest series to date and show that this may be preferable to total femoral replacement in a cohort of patients who often have significant co-morbidities.

Methodology

A retrospective analysis of patients undergoing COM between 2002–2022 was performed. Primary outcomes were defined as implant survival, displayed with survival analysis. Secondary outcomes included mortality and surgical complications. Functional outcomes included Visual Analogue Score (VAS), EuroQol-5D-3L and Musculoskeletal Tumour Society (MSTS) score at one year post operatively.

Results

34 patients underwent reconstructive cement-over technique. There were 20 custom distal femur replacements and 10 custom proximal femoral replacements. Two patients were revised, with a ten year implant survival of 94%. Fifteen patients died during the study period with an mean time to death of 66 months (25–109). The mean follow up was 75 months. 11 patients (32%) developed surgical complications. Mean VAS score was 4.9 (1–10), EuroQol-5D-3L index 0.45 (−0.59 – 0.88) and MSTS score was 16.8 (2–27) in 29 patients.

Conclusion

The COM technique provides good implant survivorship in complex cases with compromised bone stock and this series confirms this as an established alternative to total femoral replacement in these cases.
DO BODY MASS INDEX (BMI) AND PATELLOFEMORAL WEAR IMPACT ON FUNCTIONAL OUTCOMES OF UNICOMPARTMENTAL KNEE ARTHROPLASTY?
Authors: Myatt Darren , Marshall Morgan , Ankers Thomas , Robb Curtis
Published: August 2023

Unicompartment knee replacement (UKR) has been an effective treatment of isolated medial compartment osteoarthritis (OA). There has been several studies which suggest that patellofemoral (PFJ) wear may not be a relative contraindication for UKR with no statistical difference in failure rates. There is currently conflicting evidence on the role of BMI.

We will review if BMI and PFJ wear impacts on the post operative functional scores following UKR.

A retrospective review of a prospectively collected database was performed. Data was collected between 26/6/2014 and 25/8/2022. 159 UKR procedures were identified. BMI and PFJ cartilage wear were collected. Oxford knee scores (OKS) were collected at > 2 years. PFJ wear was split into International Cartilage Research Society (ICRS) grades I&II and III&IV.

159 UKR procedures were identified, of these 115 had 2 year follow up. There were 77 who had OKS recorded at 2 years. For PFJ wear there was no statistical difference in the median OKS at 2 years 45 vs 43.5 (p=0.408). Assessing the BMI the median was 29kg/m2, range 20–43kg/m2. Spearman's rank was performed to assess the correlation between BMI and >2 year OKS, this demonstrated a moderately negative correlation p(df)=−0.339 (CI 95% −0.538, −0.104) p=0.004.

There is no statistically significant difference in >2 year OKS following UKR regardless of PFJ wear. There is a moderately negative correlation between BMI and >2 year OKS which was significant p=0.004. Therefore BMI is a more important consideration when counselling patients for UKR.
IMPLEMENTATION AND EVOLUTION OF THE REGIONAL REVISION KNEE ARTHROPLASTY MULTIDISCIPLINARY TEAM MEETING IN SOUTH WEST LONDON
Authors: Afzal Irrum , Radha Sarkhell , Mitchell Philip
Published: August 2023

Multidisciplinary team (MDT) meetings in orthopaedic surgery are evolving. The goals include patient optimisation, surgical planning and discharge arrangements, individually on a patient specific basis. In line with British Association Surgery of the Knee and GIRFT guidelines, we report our regional experience on the implementation and evolution of our regional Revision Knee Arthroplasty MDT.

We undertook a retrospective review of the process, cases discussed and quality assurance conducted in the weekly MDT.

Since implementation of the MDT meeting in January 2019, 550 patients with painful joint replacements have been discussed. In May 2021, we formalised our ‘terms of reference’ and ‘standard operating procedures’ which are adhered to by the consultants operating within the network, all of whom attend the meeting. A proforma has been developed and is completed for all cases capturing all pertinent information. All cases are graded according to R1, R2, or R3 complexity scale. Since its inception, the MDT has looked at all post-operative imaging, we now describe a new classification system for grading the appearances. Confirmation of the pre-operative plan and actual surgical intervention is reviewed and audited. In addition, confirmation of indication of revision at the time of operation is reviewed and validated for accuracy with benefits to the unit, individual surgeon and the NJR.

In conclusion, the implementation of the revision MDT facilitating pre-operative revision arthroplasty discussion and post-operative quality assurance processes enable surgeons to educate, reflect on their practice and ensure that the highest standards of care are being provided.
ARE GOOD OUTCOMES IN TOTAL KNEE ARTHROPLASTY PREDICTIVE OF SUCCESS IN SEQUENTIAL CONTRALATERAL SURGERY?
Authors: Haque Seraj , Downie Samantha , Ridley David , Dalgleish Stephen , Nicol Graeme
Published: August 2023

Introduction

There is little published literature to support the claim that a successful total knee replacement (TKR) is predictive of future good outcomes on the contralateral side. The objective was to identify whether outcome from the first of staged TKRs could be used to predict the outcome of the contralateral TKR.

Methodology

This was a retrospective cohort study of 1687 patients over a 25-year period undergoing staged bilateral TKRs in a UK arthroplasty centre. A control group of 1687 patients undergoing unilateral TKR with matched characteristics was identified.

Primary outcomes: satisfaction and Knee Society Score (KSS) at one year.

Results

Preoperative status was comparable for pain, ROM and KSS (mean 41, 45, 43±14).

At one year, dissatisfaction was similar for all groups (4% first of staged TKR, 4% second of staged TKR, 5% controls). If the first TKR had a good outcome, the relative risk of a contralateral bad outcome was 20% less than controls (95% CI 0.6–1.2). If the first TKR had a poor outcome, the risk of a second poor outcome was 4 times higher (95% CI 2.8–6.1), increasing from 6% to 28% (absolute risk).

Conclusion

Patients undergoing the second of staged TKRs with a previous good outcome are likely to do well in their second procedure (94 in 100 will go on to have a second good outcome). Of those with a previous poor outcome, 28 in 100 will have a second poor outcome. The trend was persistent despite correcting for gender, age, BMI, and diagnosis.
DIFFERENCES IN EARLY RECOVERY FOLLOWING UNICOMPARTMENTAL KNEE ARTHROPLASTY WITH DAY-CASE AND STANDARD CARE PATHWAYS, ASSESSED USING NOVEL PATIENT-REPORTED MEASURES
Authors: Rahman Azmi , Strickland Louise , Pandit Hemant , Jenkinson Crispin , Murray David
Published: August 2023

Background

Daycase pathways which aim to discharge patients the same day following Unicompartmental Knee Replacement have been introduced in some centres, though most continue with Standard pathways. While Daycase pathways have cost savings, recovery data comparing pathways is limited. This study aims to compare patient-reported early recovery between Daycase and Standard pathways following UKR.

Method

This study was carried out in two centres that originally used the same Standard recovery pathway for UKR. In one centre, the Standard pathway was modified into a Daycase pathway. 26 Daycase-Outpatient, 11 Daycase-Inpatient, and 18 Standard patients were recruited. Patients completed the Oxford Arthroplasty Early Recovery Score (OARS) and SF-36 (Acute) measure between Days 1–42.

Results

Standard patients had significantly better Day-1 scores than Daycase patients, but this difference rapidly diminished, and from Day-3 onwards both groups had near-identical scores (OARS Day-1, 59 vs 37, p=0.002, stemming from differences in Pain, Nausea/Feeling-Unwell, Function/Mobility subscores p=0.003,0.014,0.011. OARS Day-3 48 vs 49, p=0.790).

Daycase-Outpatients had a higher overall OARS (p=0.002), recovering 1–2 weeks faster than Daycase-Inpatients. OARS subscores demonstrated that Daycase-Outpatients had better Pain, Nausea/Feeling-Unwell, Fatigue/Sleep scores (p=0.020,0.0004,0.019 respectively). SF-36 scores corroborate OARS scores.

Conclusion

The Standard cohort had better Day-1 scores than the Daycase cohort, likely due to later mobilisation and stronger inpatient analgesia; these differences diminished by Day-3. Daycase-Outpatients recovered substantially faster than Daycase-Inpatients – likely due to the factors that delayed their discharge. The convergence of scores at 6 weeks demonstrates that both pathways have similar early recovery outcomes.
INTERFERENCE AND KEEL DESIGN SIGNIFICANTLY INFLUENCE SAGITTAL MICROMOTION IN CEMENTLESS UNICOMPARTMENTAL KNEE ARTHROPLASTY
Authors: Rahman Azmi , Heath David , Mellon Stephen , Murray David
Published: August 2023

Introduction

In cementless UKR, early post-operative tibial fractures are 7x more common in very small tibias. A smaller keel has been shown to reduce this fracture risk, but its effect on fixation is unassessed. This mechanical study assesses the effect of keel interference and size on sagittal micromotion of the tibial component in physiological loading positions.

Method

A high-resolution Digital Image Correlation setup was developed and validated to an accuracy of 50 micrometres. Variants of tibial components were 3D-printed: standard, no-interference, no-keel, and a new small keel. Components were implanted into bone-analogue foam which was machined to a CT-reconstructed small tibia, using surgical technique. Tibias were loaded to 200N in physiological loading positions: 8mm (step-up) and 15mm (lunge) posterior to midpoint, and micromotion was assessed.

Results

In all tests, anterior lift-off was the largest micromotion observed. In ‘step-up’, a standard keel moved more than the no-interference and no-keel variants (340μm-vs-63μm-vs-30μm, p=0.002). In ‘lunge’ loading, the no-interference and no-keel variants moved more than the standard (826μm-vs-1003μm-vs-521μm, p=0.039).

The small keel experienced less micromotion in ‘step-up’ (245μm-vs-340μm p=0.233, overall p=0.009) and ‘lunge’ (378μm-vs-521μm p=0.265, overall p=0.006) than the standard keel.

Conclusion

The keel protects against large tibial micromotion during lunge movement. Counterintuitively, interference increases micromotion during step-up movement, likely due to implant pivoting around the bone-keel interface. Results suggest patients should be advised against lunge movements early post-operatively. The new smaller keel fixes similarly or better than the standard keel, making it viable for replacing the standard keel to potentially reduce fracture risk.
PROSPECTIVE RANDOMIZED STUDY USING PHARMACOGENETICS TO OPTIMIZE PERIOPERATIVE PAIN MANAGEMENT AFTER TOTAL KNEE ARTHROPLASTY
Authors: Kraus Molly , Bingham Joshua , Kekic Adrijana , Erickson Colby , Grilli Christopher , Seamans David , Upjohn David , Hentz Joseph , Clarke Henry , Spangehl Mark
Published: August 2023

Introduction

Adverse reactions to pain medication and pain can delay discharge after outpatient knee arthroplasty (TKA). Pharmacogenomics is an emerging tool that might help reduce adverse events by tailoring medication use based on known genetic variations in the CYP genes determining drug metabolism. This study was undertaken to evaluate whether pre-operative pharmacogenomic testing could optimize peri-operative pain management in patients undergoing total knee arthroplasty (TKA).

Methods

This prospective, randomized study was performed in adults undergoing primary TKA. Patients in the experimental group underwent pre-operative pharmacogenomic evaluation and medication adjustments. Medications were not optimized for control patients. The Overall Benefit of Analgesic Score (OBAS) at 24 hours post-op was the primary outcome. Postoperative pain scores (VAS scale), total opioid use, time in recovery, and time to discharge were also compared.

Results

76 patients enrolled. 93% of patients had a poor-intermediate phenotype for at least one of four CYP genes. OBAS did not differ significantly between the two groups (4.2 control vs. 4.7 experimental; 95% CI −1.1 to 2.1) and was below the minimum clinically important difference of 2.0 points. Furthermore, there were no differences in any OBAS subscale including pain, satisfaction, or nausea. There were no differences in time in the recovery area or to discharge from hospital, or narcotic use.

Conclusions

Despite many patients having a poor-intermediate phenotype for a CYP gene, pharmacogenomic testing prior to TKA and medication adjustment did not improve anesthesia or pain management outcomes, time to discharge or mean total opioid use after surgery.
ITEM RESPONSE THEORY VALIDATION OF THE FORGOTTEN JOINT SCORE FOR PEOPLE UNDERGOING TOTAL KNEE ARTHROPLASTY
Authors: Khatri Chetan , Harrison Conrad , Scott Chloe , Clement Nick , MacDonald Deborah , Metcalfe Andrew , Rodrigues Jeremy
Published: August 2023

Background

The Forgotten Joint Score (FJS) is a 12-item patient reported outcome measurement instrument. It was developed with classical test theory, without testing assumptions such as unidimensionality (all items reflect one underlying factor), appropriate weighting of each item, no differential item function (DIF, different groups answer the same way), and monotonicity (people with higher function have higher score). We applied item response theory (IRT) to improve the validity of FJS to contemporary standards to optimise it for ongoing use.

Research Questions

Does the FJS reflect one latent trait? Can an IRT model be fitted to the FJS to provide interval-scaled measurement?

Methodology

Participants undergoing primary total knee replacement provided pre-operative and post-operative (6-months) responses for FJS. An exploratory factor analysis (EFA), confirmatory factor analysis (CFA) and Mokken analysis were conducted. The data were fitted to a graded response model (GRM).

Results

1288 response patterns were analysed. EFA showed a one factor model (all 12 items load to one underlying trait). CFA demonstrated excellent model fit (X2 <0.001, Tucker Lewis Index=0.96, Comparative Fit Index=0.96). Items did not have equal weighting. The FJS demonstrated good monotonicity with no differential item functioning by sex, age, or body mass index.

Conclusions

The FJS meets key validity assumptions supporting its use in clinical practice and research. The IRT-adapted FJS provides continuous measurements with greater granularity including individual measurement error. This adapted score has advantages over traditional FJS scoring, being interval scaled (using GRM) and can be retrospectively applied to existing response sets.
EXTRA-ARTICULAR KNEE LIGAMENT RECONSTRUCTIONS USING LARS (LIGAMENT AUGMENTATION AND RECONSTRUCTION SYSTEM) SYNTHETIC GRAFTS IN ELITE ATHLETES
Authors: Ball Simon , Jones Mary , Pinheiro Vitor Hugo , Church Sam , Williams Andy
Published: August 2023

Introduction

The aim of this study was to determine if elite athletes could return to professional sport after MCL or PLC reconstruction using LARS ligaments and to demonstrate the safety and efficacy of LARS by reporting sport longevity, subsequent surgeries and complications.

Methods

A retrospective review of all extra-articular knee ligament reconstructions in elite athletes utilising LARS ligaments by 3 knee surgeons between January 2013 and October 2020 was undertaken. Return to play (RTP) was defined as competing at professional level or national/ international level in amateur sport.

Results

Sixty-four (84.2%) MCL and 12 (15.8%) PLC reconstructions utilising LARS in elite athletes were included. 52 (68.4%) underwent concomitant cruciate(s) reconstruction. The mean age was 25.1 years (SD +/− 4.50. Most were football (35, 46.1%) or rugby players (35, 46.1%).

Sixty-seven athletes (88.2%) RTP with 65 (97.0%) of these playing at the same or higher Tegner level. 56 (83.6%) and 20 (57.1%) were still playing at 2 and 5 years post-surgery.

Six (7.9%) players (5 of whom RTP) required further surgery relating to the LARS / metalwork and there was one case of adverse local inflammatory reaction to the synthetic material. There was one MCL re-rupture, sustained 4 years after RTP.

Conclusion

Utilising LARS in extra-articular knee ligament reconstructions allows 88.2% of athletes, with a variety of knee ligament injuries, to return to elite sport. The low morbidity rates coupled with 57% of athletes still playing 5 years post-surgery suggests the LARS is safe and effective in these cases.
COMPARISON OF SIMPLIFIED MCL RECONSTRUCTIONS TO CONTROL VALGUS AND ANTEROMEDIAL ROTATORY INSTABILITY (AMRI): BIOMECHANICAL EVALUATION IN VITRO
Authors: Bartolin Petra Bonacic , Shatrov Jobe , Ball Simon V , Holthof Sander R , Williams Andy , Amis Andrew A
Published: August 2023

Introduction

Previous research has shown that, notwithstanding ligament healing, properly selected MCL reconstruction can restore normal knee stability after MCL rupture. The hypothesis of this work was that it is possible to restore knee stability (particularly valgus and AMRI) with simplified and/or less-invasive MCL reconstruction methods.

Methods

Nine unpaired human knees were cleaned of skin and fat, then digitization screws and optical trackers were attached to the femur and tibia. A Polaris stereo camera measured knee kinematics across 0o-100o flexion when the knee was unloaded then with 90N anterior-posterior force, 9Nm varus-valgus moment, 5Nm internal-external rotation, and external+anterior (AMRI) loading. The test was conducted for the following knee conditions: intact, injured: transected superficial and deep MCL (sMCL and dMCL), and five reconstructions: (long sMCL, long sMCL+dMCL, dMCL, short sMCL+dMCL, short sMCL), all based on the medial epicondyle isometric point and using 8mm tape as a graft, with long sMCL 60mm below the joint line (anatomical), short sMCL 30mm, dMCL 10mm (anatomical).

Results

No significant changes were found in anterior or posterior translation, or varus at any stage. MCL deficiency caused increased valgus, external rotation and AMRI instabilities. All reconstructions restored valgus stability. The isolated long sMCL allowed residual external rotation and AMRI instability, while the short sMCL did stabilise AMRI. Both 2-strand reconstructions (dMCL+sMCL) restored stability.

Conclusion

All tested techniques, except long sMCL, restored valgus and AMRI stability of the knee. The single femoral tunnel is satisfactory for both the dMCL and sMCL grafts.
A WEARABLE SENSING SYSTEM FOR CONTINUOUS MONITORING OF KNEE CONDITION
Authors: Alabdullah Meernah , Liu Aiqin , Xie Shane
Published: August 2023

Rehabilitation exercise is critical for patients’ recovery after knee injury or post-surgery. Unfortunately, adherence to exercise is low due to a lack of positive feedback and poor self-motivation. Therefore, it is crucial to monitor their progress and provide supervision. Inertial measurement unit (IMUs) based sensing technology can provide remote patient monitoring functions. However, most current solutions only measure the range of knee motion in one degree of freedom. The current IMUs estimate the orientation-angle based on the integrated raw data, which might lack accuracy in measuring knee motion. This study aims to develop an IMU-based sensing system using the absolute measured orientation-angle to provide more accurate comprehensive monitoring by measuring the knee rotational angles.

An IMU sensing system monitoring the knee joint angles, flexion/extension (FE), adduction/abduction (AA), and internal/external (IE) was developed. The accuracy and reliability of FE measurements were validated in human participants during squat exercise using measures including root mean square error (RMSE) and correlation coefficient.

The RMSE of the three knee angles (FE, AA, and IE) were 0.82°, 0.26°, and 0.11°, which are acceptable for assessing knee motion. The FE measurement was validated in human participants and showed excellent accuracy (correlation coefficient of 0.99°). Further validation of AA and IE in human participants is underway.

The sensing system showed the capability to estimate three knee rotation angles (FE, AA, and IE). It showed the potential to provide comprehensive continuous monitoring for knee rehabilitation exercises, which can also be used as a clinical assessment tool.
NOVEL SINGLE-STRAND ‘SHORT ISOMETRIC CONSTRUCT’ (SIC) MEDIAL COLLATERAL LIGAMENT RECONSTRUCTION RESTORES VALGUS AND ROTATIONAL STABILITY THROUGHOUT KNEE RANGE OF MOTION
Authors: Borque Kyle , Han Shuyang , Gold Jonathan , Sij Ethan , Laughlin Mitzi , Amis Andrew , Williams Andy , Noble Philip , Lowe Walter
Published: August 2023

Introduction

Persistent medial laxity increases the risk of failure for ACL reconstruction. To address this, multiple reconstruction techniques have been created. To date, no single strand reconstruction constructs have been able to restore both valgus and rotational stability. In response to this, a novel single strand Short Isometric Construct (SIC) MCL reconstruction was developed.

Methods

Eight fresh-frozen cadaveric specimens were tested in three states: 1) intact 2) after sMCL and dMCL transection, and 3) after SIC MCL reconstruction. In each state, four loading conditions were applied at varying flexion angles: 90N anterior drawer, 5Nm tibial external rotation torque, 8Nm valgus torque, and combined 90N anterior drawer plus 5Nm tibial external rotation torque.

Results

Transection of the sMCL and dMCL resulted in increased laxity with external rotation torque, valgus torque, and combined anterior drawer plus external rotation. SIC MCL reconstruction restored external rotation and valgus stability to intact levels throughout all degrees of flexion. In the combined test SIC MCL reconstruction also restored stability to intact levels for both anterior distraction and external rotation throughout the range of motion. No significant differences were noted between intact and SIC reconstruction.

Conclusion

The single-limb short isometric construct (SIC) MCL reconstruction restored native valgus and rotatory stability to a sMCL- and dMCL-deficient knee in biomechanical testing.
FIXATION OF OSTEOCHONDRITIS DISSECANS AND TRAUMATIC OSTEOCHONDRAL FRACTURE OF THE KNEE WITH BIODEGRADABLE HEADLESS COMPRESSION SCREWS
Authors: Houston James , Everett Samuel , Choudhary Awais , Middleton Simon , Mandalia Vipul
Published: August 2023

Introduction

Symptomatic osteochondritis dissecans (OCD) and traumatic osteochondral fractures (OCF) are treated with fixation with either metal or bioabsorbable device. We performed a comparative review of patients with OCD and traumatic OCF stabilised with Bio-Compression screws which are headless absorbable compression screws. Our aim was to determine whether there was a difference in outcomes between presentations.

Methods

Retrospective single-centre cohort study of all patients with OCD and OCF treated with Bio-Compression screw between July 2017 and September 2022. All patients followed up until discharge with satisfactory clinical outcome. Primary outcome was return to theatre for ongoing pain or mechanical symptoms. Secondary outcome was evidence of fixation failure on follow-up MRI scan.

Results

20 patients included; 8 OCF and 12 OCD. Average age 21 (OCF), 24 (OCD). The most common location was patella (58%) in OCF or the medial femoral condyle (75%) in OCD. Traumatic defects were smaller (2.6cm2 vs 3.3cm2) although this was not statistically significant (p=0.28). In the OCF group one patient went on to have further surgery. There were no re-operations in the OCD group. Both groups had good outcomes and similar times to discharge. There was no evidence of fixation failure of Bio-Compression screws on MRI scans.

Conclusions

Within the limits of this relatively small cohort there is no significant difference between outcomes for OCD or traumatic OCF fixation with Bio-Compression screws. Both groups demonstrate good outcomes irrespective of the location or the aetiology of the fragment.
POLYACRYLAMIDE HYDROGEL VERSUS HYALURONIC ACID IN KNEE OSTEOARTHRITIS: A SUBGROUP ANALYSIS OF A RANDOMIZED STUDY
Authors: Bliddal Henning , Beier Jannie , Hartkopp Andreas , Conaghan Philip , Henriksen Marius
Published: August 2023

Introduction

The effectiveness of single intra-articular injections of polyacrylamide hydrogel (iPAAG) and hyaluronic acid (HA) was compared in subgroups of participants from an RCT based on baseline age, BMI or Kellgren-Lawrence (KL) grade.

Methodology

239 participants were randomised to 6 mL iPAAG (Arthrosamid; n=119) or 6 mL HA (Synvisc-One; n=120). Participants continued analgesics (except 48 hours prior to visits) and non-pharmacological therapy. Topical therapies and intra-articular corticosteroids were not allowed. Pre-specified subgroup analyses (age: <70 years, ≥70 years; BMI: normal, overweight, obese; KL grade: 2, 3, 4, 2–3) of change from baseline in WOMAC pain subscale at 52 weeks were based on the least squares means for the treatment-by-week interaction effect using a mixed model for repeated measurement with a restricted maximum likelihood-based approach.

Results

Across all patients, change from baseline in WOMAC pain subscale in the iPAAG group was non-inferior to HA at 26 weeks and approached superiority (p=0.0572) at 52 weeks. Treatment differences for change from baseline in WOMAC pain subscale in favour of iPAAG over HA were statistically significant for the age <70 years (p=0.019), BMI normal (p=0.011) and KL grade 2–3 (p=0.033) subgroups. Treatment differences for all other subgroups favoured iPAAG, except for KL grade 4 which favoured HA, without reaching statistical significance.

Conclusion

iPAAG approached superiority to HA across all participants at 52weeks, but demonstrated statistical superiority in participants with normal BMI, participants <70 years old or participants with KL score 2–3. iPAAG represents a useful alternative to HA for the treatment of knee OA.
COMPARISON OF OPEN VERSUS CLOSED REDUCTION AND FIXATION WITH LOCKING PLATES OF SUPRACONDYLAR PERIPROSTHETIC FEMORAL FRACTURES WITH STABLE PROSTHESES
Authors: Sidhu Gur Aziz Singh
Published: August 2023

INTRODUCTION

The anatomic distal femoral locking plate (DF-LCP) has simplified the management of supracondylar femoral fractures with stable knee prostheses. Osteoporosis and comminution seem manageable, but at times, the construct does not permit early mobilization. Considerable soft tissue stripping during open reduction and internal fixation (ORIF) may delay union. Biological plating offsets this disadvantage, minimizing morbidity.

Materials

Thirty comminuted periprosthetic supracondylar fractures were operated from October 2010 to August 2016. Fifteen (group A) were treated with ORIF, and fifteen (group B) with closed (biological) plating using the anatomical DF-LCP. Post-operatively, standard rehabilitation protocol was followed in all, with hinged-knee-brace supported physiotherapy. Clinico-radiological follow-up was done at 3 months, 6 months, and then yearly (average duration, 30 months), and time to union, complications, failure rates and function were evaluated.

Results

Average time to union was 4.5 months (range, 3–6 months) in group A, and 3.5 months (range, 2.5–5 months) in group B. Primary bone grafting was done in twelve patients (all group A). At final follow-up, all fractures had healed, and all (but two) patients were walking unsupported, with no pain or deformity, with average knee range of motion (ROM) of 90° (range, 55 to 100°). Two patients had superficial infection (group A), two had knee stiffness (group A), one had shortening of 1.5cm (group B) and one had valgus malalignment of 10 degrees (group B).

Conclusion

Biological plating in comminuted supracondylar fractures about stable TKA prostheses is an excellent option, may obviate need for bone grafting, and reducing complications.
LONG-TERM SURVIVAL RATES ARE SIMILAR WITH OR WITHOUT PATELLAR RESURFACING AFTER TOTAL KNEE ARTHROPLASTY, HOWEVER, HIGHER REVISION RATE WITHOUT PATELLAR RESURFACING CAN BE PROSTHETIC-SPECIFIC: A NATIONAL JOINT REGISTRY ANALYSIS
Authors: Chrastek David , Boddu Krishna
Published: August 2023

Introduction

The role of patellar resurfacing in total knee arthroplasty remains controversial. We questioned the effect of patellar resurfacing on the early and late revision rates after total knee arthroplasty.

Materials and Methods

We analysed the data of cumulative revisions of primary knee replacement from the NJR 19th Annual Report. NJR included secondary patellar resurfacing as a revision. We compared differences in the 3-year and 15-year revision rates between the patellar resurfacing and non-resurfacing for the different combinations of total knee replacements using a paired t-test. We performed subgroup analysis for the five combinations with the highest volumes.

Results

Twenty-seven implant combinations had the 15-year revision rates reported. Patellar resurfacing group had lower mean 3-year revision rate of 1.68 (SD 0.7) compared to 2.02 (SD 0.9) in non-resurfacing group (p=0.05). However, 15-year revision rate was similar between the two groups (mean 5.7, SD 2.1 vs. mean 5.7, SD 2.2; p = 0.46).

High volume implants showed that two combinations (NexGen CR and PS) had similar revision rates at 3 and 15 years between resurfacing and non-resurfacing groups. Three combinations (PFC Sigma CR and PS and Genesis 2 CR) had higher revision rate in non-resurfacing group at 3 years (p=0.01) and the difference persisted at 15 years (p=0.05).

Conclusions

Although revision rate in total knee arthroplasty was higher without patellar resurfacing at 3 years, at 15 years the difference was not significant. However, the higher revision without patellar resurfacing can be prosthetic combination specific which surgeons need to be aware of.
OUTCOME OF TREATMENT FOLLOWING ARTHROSCOPIC REPAIR OF BUCKET HANDLE MENISCUS TEARS IN ADULTS
Authors: Nanjundaiah Raghavendra , Guro Randy , Chandratreya Amit , Kotwal Rahul
Published: August 2023

Aims

We studied the outcomes following arthroscopic primary repair of bucket handle meniscus tears to determine the incidence of re-tears and the functional outcomes of these patients.

Methodology

Prospective cohort study. Over a 4-year period (2016 to 2020), 35 adult patients presented with a bucket handle tear of the meniscus. Arthroscopic meniscal repair was performed using either the all inside technique or a combination of all-inside and inside-out techniques. 15 patients also underwent simultaneous arthroscopic anterior cruciate ligament reconstruction. Functional knee scores were assessed using IKDC and Lysholm scores.

Results

Mean patient age at surgery was 27 years (range, 17 to 53years). Medial meniscus was torn in 20 and lateral in 15 cases. Zone of tear was white on white in 19, red on white in 9 and red on red in 7 cases. Average delay from injury to surgery was 4 months. At a mean follow-up of 4.5 years, the meniscus repair failed in 3 patients (8.5 %). Outcome following re-tear was meniscus excision. Average IKDC scores in patients with intact repair were 74.04 against 56.67 in patients with a failed repair (p< 0.0001). Similarly, Lyshlom scores were 88.96 and 67.333, respectively (p<0.0001).

Conclusion

The survivorship of primary repair of bucket handle meniscus tears in our series was 91.5% at medium term follow-up. Functional outcomes were significantly poor in patients with a failed repair compared to those with an intact repair.
Esp8266 module use in animal production: a review
Authors: Zanetoni Hiago Henrique Rocha , Souza Maria Angela de , Paranhos Charles de Oliveira , Queiroz Daniel Marçal de , Sousa Fernanda Campos de
Published: August 2023

The thermal environment in livestock buildings affects the productive and reproductive performance of animals. Therefore, monitoring thermal environment variables is necessary. This study reviewed the applicability of the electronic device ESP8266 module to monitoring animal production. The ESP8266 module is a microcontroller that enables the collection, storage and transmission of data that influence livestock production. The data collected are transferred to cloud computing systems allowing the development of supervisory systems that can be accessed by smartphones, tablets or computers. With this type of microprocessor, it is possible to develop autonomous management systems for animal production. Connected devices using the internet of things, artificial intelligence, machine learning and blockchain will facilitate the analysis of data from the production chain and the appropriate decision-making. Managers of livestock production systems will be in charge of following up and monitoring the processes.
Dynamic 3D phase-shifting profilometry based on a corner optical flow algorithm
Authors: Lu Shi , Weng Hui , Dai Mingyou , Zhang Bohan , Xu Zhengyang , Gu Haoshuang , Liu Y. , Li Yuebin , Peng Kuang
Published: August 2023

Real-time 3D reconstruction has been applied in many fields, calling
for many ongoing efforts to improve the speed and accuracy of the used
algorithms. Phase shifting profilometry based on the Lucas–Kanade
optical flow method is a fast and highly precise method to construct
and display the three-dimensional shape of objects. However, in this
method, a dense optical flow calculation is required for the
modulation image corresponding to the acquired deformed fringe
pattern, which consumes a lot of time and affects the real-time
performance of 3D reconstruction and display. Therefore, this paper
proposes a dynamic 3D phase shifting profilometry based on a corner
optical flow algorithm to mitigate this issue. Therein, the Harris
corner algorithm is utilized to locate the feature points of the
measured object, so that the optical flow needs to calculate for only
the feature points which, greatly reduces the amount of calculation
time. Both our experiments and simulations show that our method
improves the efficiency of pixel matching by four times and 3D
reconstruction by two times.
Laser beam array spot steering customized trajectories using the acousto-optic effect
Authors: Guessoum Amir , Bencheikh Abdelhalim
Published: August 2023

We demonstrate a proof of principle of a technique for array laser beam steering according to a generalized elliptical path, using the acousto-optic effect. We explore the dynamic trajectories of the diffraction orders of a Gaussian beam, diffracted by a dynamic 2D sinusoidal phase grating. The latter is generated by two crossed acoustic waves propagating in a transparent medium, giving rise to 2D dynamic sinusoidal refractive index variation. We particularly emphasize the case where the two crossed acoustic waves are modulated in frequency and have a phase difference. In such case, the resulting diffraction orders are dynamic and follow some particular trajectory’s shapes, from linear and circular to generalized elliptical shapes. Inspired by Poincaré and Bloch spheres used to represent polarization and quantum states, we suggest the sphere volume trajectory shape to represent all trajectories’ shapes of all diffraction orders.
Ultra-large near-infrared omnidirectional photonic bandgaps in cascaded one-dimensional photonic crystals containing all-dielectric metamaterials
Authors: Cheng Zhaoming , She Yuchun , Panda Abinash , Feng Mingku , Li Jiaosheng , Wu Feng
Published: August 2023

In conventional one-dimensional (1-D) photonic crystals (PCs) consisting of isotropic dielectrics, photonic bandgaps (PBGs) substantially shift toward shorter wavelengths as incident angle increases. This strong blueshift characteristic of PBGs significantly reduces the widths of near-infrared omnidirectional photonic bandgaps (OPBGs). Recently, researchers achieved a kind of special PBG called angle-insensitive PBGs in 1-D PCs containing all-dielectric elliptical metamaterials (EMMs). The emergence of angle-insensitive PBGs provides us a possibility to achieve ultra-large near-infrared OPBGs. Herein, we design two 1-D PCs containing all-dielectric EMMs with near-infrared angle-insensitive PBGs in different wavelength ranges. By cascading two 1-D PCs containing all-dielectric EMMs together, we achieve an ultra-large near-infrared OPBG with a width up to 1.004 µm (relative bandwidth of 63.9%). In addition, the width of the near-infrared OPBG demonstrates robustness against the layer thickness. Our work not only provides a feasible route to achieving ultra-large near-infrared OPBGs, but also facilitates the design of broadband omnidirectional mirrors.
Large lateral photovoltaic effect with ultrafast optical relaxation time in SnS2/n-Si junctions
Authors: Zhu Ziyao , Ouyang Zining , Hu Junbei , Qi Hongkai , Pei Yujuan , Zhang Lingli , Wang Xianjie
Published: August 2023

A large lateral photovoltaic effect (LPE) with a fast optical response time is necessary to develop high-performance position-sensitive detectors. In this paper, we report an LPE with a high self-powered position sensitivity and ultrafast optical relaxation time in SnS2/n−Si junctions prepared using pulsed laser deposition. A large built-in electric field was generated at the SnS2/Si interface, which resulted in a large LPE with a positional sensitivity of up to 116 mV/mm. Furthermore, the measurement circuit with multiple parallel resistors had a strong influence on the ultrafast optical response time of the LPE and the fastest optical relaxation time observed was ∼0.44µs. Our results suggest that the SnS2/Si junction would be a promising candidate for a wide range of optoelectronic device applications.
Humanoid-shaped WaveFlex biosensor for the detection of food contamination
Authors: Singh Ragini , Zhang Wen , Liu Xuecheng , Zhang Bingyuan , Kumar Santosh
Published: August 2023

High-toxicity secondary metabolites called aflatoxin are naturally
produced by the fungus Aspergillus. In a warm, humid
climate, Aspergillus growth can be considerably
accelerated. The most dangerous chemical among all aflatoxins is
aflatoxin B1 (AFB1), which has the potential to cause cancer and
several other health risks. As a result, food forensicists now
urgently need a method that is more precise, quick, and practical for
aflatoxin testing. The current study focuses on the development of a
highly sensitive, specific, label-free, and rapid detection method for
AFB1 using a novel humanoid-shaped fiber optic WaveFlex biosensor
(refers to a plasmon wave-based fiber biosensor). The fiber probe has
been functionalized with nanomaterials (gold nanoparticles, graphene
oxide and multiwalled carbon nanotubes) and anti-AFB1 antibodies to
enhance the sensitivity and specificity of the developed sensor. The
findings demonstrate that the developed sensor exhibits a remarkable
low detection limit of 34.5 nM and exceptional specificity
towards AFB1. Furthermore, the sensor demonstrated exceptional
characteristics such as high stability, selectivity, reproducibility,
and reusability. These essential factors highlight the significant
potential of the proposed WaveFlex biosensor for the accurate
detection of AFB1 in diverse agricultural and food samples.
Design of an ultra-wideband switchable terahertz metamaterial absorber using a VO2 transversally open ring structure
Authors: Li Jing , Ma Binyi , Liu Yanfei , Guo Honglei , Wu Qiannan , Li Mengwei
Published: August 2023

This paper proposes a switchable terahertz (THz) metamaterial absorber based on vanadium dioxide (VO2), which can not only realize ultra-wideband (UWB) perfect absorption in the THz range, but also has the ability to adjust the absorption rate by regulating the conductivity of VO2. When VO2 conductivity is 2×105S/m, the designed UWB absorber can achieve over 90% absorption in the frequency range of 2.62–10 THz. Simultaneously, the peak absorption intensity of the absorber can also be regulated dynamically ranging from 100% to 0.8% when the conductivity of VO2 is adjusted to change from 2×105 to 20 S/m. Furthermore, the designed absorber has the advantages of polarization insensitivity and wide-angle absorption. For TE polarization with an incident angle of less than 40° and TM polarization with an incident angle of less than 60°, the absorption rate remains above 90%. The UWB absorber has the advantages of simple structure, wide tuning range, and good absorption performance, and it has potential applications in many fields such as THz filtering, invisibility, sensing, optoelectronic switches, and so on.
Performance of polar coded probabilistic shaped PAM8 with systematic interleaver and identically distributed pilot in weak turbulence
Authors: Liu Xiaoyu , Liu Zhiyang , Xiao Shilin , Fu Xiangyu , Yang Weiying , Hu Weisheng
Published: August 2023

In this paper, for the first time to the best of our knowledge, we investigate the experiment of polar coded probabilistic shaped 8-ary pulse amplitude modulation (PS-PAM8) in weak turbulence. A systematic interleaver (SIL) is proposed to improve the polar code performance for PS-PAM8, compatible with the 5 G channel coding standard. Considering the effects of turbulence and shaped constellations, the pilot with identical distributions as the transmitted data is used for dynamic channel estimation to avoid demodulation failure. Moreover, the application of hybrid equalization with nonlinear and linear equalizers effectively reduces the receiver sensitivity. In 25 GBd transmission over a 4 m free-space link, the transmission performance of polar coded PAM8 schemes with SIL is better than that of the low-density parity check code by 1.0 dB, and the power budget is further saved by 0.72∼0.83 dB after linear equalization. Meanwhile, the shaping gains of polar coded PS-PAM8 with SIL and hybrid equalization are up to 2.0 dB at 1.5 bits/channel use. In addition, different weak turbulence conditions can be generated inside a chamber, and the observed channel fading is consistent with the log-normal model. The results show that the proposed polar coded PS scheme can improve the Q-factor by 0.49∼1.74 dB in different turbulence conditions.