Introduction

The mobile-bearing (MB) total knee arthroplasty (TKA) design was introduced with the aim of reducing polyethylene wear and component loosening seen in the fixed-bearing (FB) design. A recent joint registry study has revealed increased risk for all-cause revision, but not revision for infection, in MB-TKA. We used the New Zealand Joint Registry (NZJR) to compare all-cause revision rates, and revision rates for aseptic loosening of MB-TKA compared with fixed bearing (FB) TKA.

Methods

All patients who underwent a primary TKA registered in the NZJR between the 1st January 1999 to 31st December 2021 were identified. Analysis compared MB to FB designs, with sub analysis of implants from a single company. We identified 135,707 primary TKAs, with 104,074 (76.7%) FB-TKAs and 31,633 (23.3%) MB-TKAs recorded. We examined all-cause revision rates, reasons for revision and performed survival analyses.

Introduction

A key outcome measured by national joint registries are revision events. This informs best practice and identifies poor-performing surgical devices. Although registry data often record reasons for revision arthroplasty, interpretation is limited by lack of standardised definitions of revision reasons and objective assessment of radiologic and laboratory parameters. Our study aim was to compare reasons for unicompartmental knee arthroplasty (UKA) revision reported to the New Zealand Joint Registry (NZJR) with reasons identified by independent clinical review.

Methods

A total of 2,272 patients undergoing primary medial and lateral UKA at four large tertiary hospitals between 2000 and 2017 were included. A total of 158 patients underwent subsequent revision with mean follow-up of 8 years. A systematic review of clinical findings, radiographs and operative data was performed to identify revision cases and to determine the reasons for revision using a standardised protocol. These were compared to reasons reported to the NZJR using Chi-squared and Fisher exact tests.

Introduction

This study assessed outcomes of total knee joint replacements (TKJR) in patients who had undergone previous periarticular osteotomy compared with unicompartmental knee replacement (UKR). Establishing a difference in the results of total knee joint replacements following these operations may be an important consideration in the decision-making and patient counselling around osteotomy versus UKR for the management of single-compartment osteoarthritis.

Method

Using data from the New Zealand Joint Registry, we identified 1,895 total knee joint replacements with prior osteotomy and 1,391 with prior UKR. Revision rates and patient-reported outcomes, as measured by the Oxford Knee Score (OKS), between these two groups were compared. Adjusted hazard ratios were also calculated to compare the groups.

Introduction

Debridement, antibiotics irrigation and implant retention (DAIR) is a common management strategy for hip and knee prosthetic joint infections (PJI). However, failure rates remain high, which has led to the development of predictive tools to help determine success. These tools include KLIC and CRIME80 for acute-postoperative (AP) and acute haematogenous (AH) PJI respectively. We investigated whether these tools were applicable to a Waikato cohort.

Method

We performed a retrospective cohort study that evaluated patients who underwent DAIR between January 2010 and June 2020 at Waikato Hospital. Pre-operative KLIC and CRIME80 scores were calculated and compared to success of operation. Failure was defined as: (i) need for further surgery, (ii) need for suppressive antibiotics, (iii) death due to the infection. Logistic regression models were used to calculate the area under the curve (AUC).

Introduction

The first VRAS TKA was performed in New Zealand in November 2020 using a Patient Specific Balanced Technique whereby VRAS enables very accurate collection of the bony anatomy and soft tissue envelope of the knee to plan and execute the optimal positioning for a balanced TKA

Method

The first 45 VRAS patients with idiopathic osteoarthritis of the knee was compared with 45 sequential patients who underwent the same TKA surgical technique using Brainlab 3 which the author has used exclusively in over 1500 patients. One and two year outcome data will be presented

Introduction

Robotic-assisted total knee arthroplasty (TKA) has demonstrated significant benefits, including improved accuracy of component positioning compared to conventional jig-based TKA. However, previous studies have often failed to associate these findings with clinically significant improvements in patient-reported outcome measures (PROMs). Inertial measurement units (IMUs) provide a more nuanced assessment of a patient's functional recovery after TKA. This study aims to compare outcomes of patients undergoing robotic-assisted and conventional TKA in the early postoperative period using conventional PROMS and wearable sensors.

Method

100 patients with symptomatic end-stage knee osteoarthritis undergoing primary TKA were included in this study (44 robotic-assisted TKA and 56 conventional TKA). Functional outcomes were assessed using ankle-worn IMUs and PROMs. IMU- based outcomes included impact load, impact asymmetry, maximum knee flexion angle, and bone stimulus. PROMs, including Oxford Knee Score (OKS), EuroQol-Five Dimension (EQ-5D-5L), EuroQol Visual Analogue Scale (EQ-VAS), and Forgotten Joint Score (FJS-12) were evaluated at preoperative baseline, weeks 2 to 6 postoperatively, and at 3-month postoperative follow-up.

Introduction

Recent technological advancements have led to the introduction of robotic-assisted total knee arthroplasty to improve the accuracy and precision of bony resections and implant position. However, the in vivo accuracy is not widely reported. The primary objective of this study is to determine the accuracy and precision of a cut block positioning robotic arm.

Method

Seventy-seven patients underwent total knee arthroplasty with various workflows and alignment targets by three arthroplasty-trained surgeons with previous experience using the ROSA® Knee System. Accuracy and precision were determined by measuring the difference between various workflow time points, including the final pre-operative plan, validated resection angle, and post-operative radiographs. The mean difference between the measurements determined accuracy, and the standard deviation represented precision.

Introduction

Acetabular component loosening with associated bone loss is a challenge in revision hip arthroplasty. Trabecular Metal (TM) by Zimmer Biomet has been shown to have greater implant survivorship for all-cause acetabular revision in small cohort retrospective studies. Our study aims to review outcomes of acetabular TM implants locally.

Method

This is a retrospective observational study using data from Auckland City and North Shore Hospitals from 1st of January 2010 to 31st of December 2020. Primary outcome is implant survivorship (re-revision acetabular surgery for any cause) demonstrated using Kaplan-Meier analysis. Secondary outcome is indication for index revision and re-revision surgery. Multivariate analysis used to identify statistically significant factors for re-revision surgery.

Background

Increasing evidence suggests a link between the bearing surface used in total hip arthroplasty (THA) and the occurrence of infection. It is postulated that polyethylene has immunomodulatory effects and may influence bacterial function and survival, thereby impacting the development of periprosthetic joint infection (PJI). This study aimed to investigate the association between polyethylene type and revision surgery for PJI in THA using data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). We hypothesized that the use of XLPE would demonstrate a statistically significant reduction in revision rates due to PJI compared to N-XLPE.

Methods

Data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) spanning September 1, 1999, to December 31, 2021, were used to compare the infection revision rates between THA using N-XLPE and XLPE. We calculated the Cumulative Percentage Revision rate (CPR) and Hazard Ratio (HR) while controlling for factors like age, sex, body mass index (BMI), American Society of Anesthesiologists’ (ASA) grade, and head size.

Background

Obesity has been linked with increased rates of knee osteoarthritis. Limited information is available on the survival and functional outcome results of rTKR in the obese patients. This registry-based study aimed to identify whether BMI is an independent risk factor for poorer functional outcomes and /or implant survival in rTKA.

Methods

New Zealand Joint Registry (NZJR) data of patients who underwent rTKA from 1st January 2010 to January 2023 was performed. Demographics, American Society of Anesthesiologists (ASA), BMI, Operative time, indications for revision and components revised of the patients undergoing rTKA was collected. Oxford knee score (OKS) at 6 months and rates of second revision (re- revision) were stratified based on standardised BMI categories.

Introduction

A common acute orthopaedic presentation is an ulcerated or infected foot secondary to diabetic neuropathy. Surgical debridement or amputation are often required to manage this complication of diabetes. International literature indicates that amputation may lead to further complications and an increased mortality rate. The aim of this study is to investigate the mortality rate associated with different surgical interventions. This will inform surgical management of patients presenting with acute foot complications from diabetes.

Methods

This is a retrospective review of patients with diabetic foot infections aged >16 years attending Middlemore Hospital over a 10-year period (2012–2021). Clinical records were examined to determine whether patients were managed with no surgery, surgery but not amputation, or amputation. We recorded relevant baseline characteristics and comorbidities. Regression models were used to determine factors associated with mortality.

Introduction

Comparative studies examining Fixed-Bearing (FB) and Mobile-Bearing (MB) Total Ankle Replacement (TAR) designs have demonstrated similar results and successful long-term outcomes for both. To date there has been no study directly comparing FB and MB designs of the same prosthesis. We present the first prospective randomised trial comparing patient satisfaction, functional outcomes and radiographic results of the Salto Talaris Fixed-Bearing and the Salto Mobile-Bearing Total Ankle Replacement in the treatment of end-stage ankle arthritis.

Methods

A total of 108 adult patients with end-stage ankle arthritis were enrolled in the study between November 2014 and October 2021 with similar demographic comparison. Prospective patient-reported outcomes and standardised weightbearing ankle radiographs were performed preoperatively, at 6 weeks, 6 months and 12 months post-operatively, followed by yearly intervals. All surgeries were performed by a single non-design orthopaedic foot and ankle specialist with experience in over 200 Salto and Salto Talaris TAR prior to the study. Radiographs were examined independently by two clinicians. Complete patient data and radiographs were available for 103 patients with an average follow up of 2 years.

Introduction

A subset of patients in cast awaiting fixation of ankle fractures require conversion to delayed external fixation (dEF). We aimed to evaluate the effect of delayed versus planned external fixation (pEF), then identify objective characteristics contributing to need for conversion.

Method

We extracted data from our booking system to identify all ankle external fixation procedures between 2010 to 2022. Exclusions included open fractures, the skeletally immature, and pilon or talus fractures. Fractures were classified using the AO/OTA classification, then a matched cohort was identified based on fracture classification. We compared the planned, delayed and matched cohorts for demographics, posterior malleolar fragment (PMF) ratio, and degree of displacement at presentation.

Introduction

The condition of the soft tissues surrounding an ankle fracture influences timing and treatment of injuries. Conventional treatment used an open approach to facilitate anatomical reduction and rigid internal fixation. Intramedullary devices for fibular fractures provide a safe alternative in patients in which the condition of the soft tissue envelope or the patient's co-morbidities may benefit from a less invasive approach. We compared outcomes for patients treated with open reduction internal fixation (ORIF) with those undergoing treatment with fibular nails (FN)

Methods

13 consecutive patients treated with fibular nails (FN) were compared with 13 age-matched patients that underwent open reduction and internal fixation (ORIF). All patients were followed to union. Study outcomes were time from admission to surgery, length of stay, wound failure, implant failure, revision surgery, OMAS and SF-36

INTRODUCTION

Stimulation of angiogenesis via the delivery of growth factors (GFs) like vascular endothelial growth factor (VEGF) is a promising strategy for the treatment of avascular necrosis (AVN). Tyraminated poly-vinyl-alcohol hydrogels (PVA-Tyr), which have the ability to covalently incorporate GFs, were proposed as a platform for the controlled delivery of therapeutic levels VEGF to the necrotic areas[1]. Nevertheless, PVA hydrophilicity and bioinertness limits its integration with the host tissues. The aim of this study was to investigated the effectiveness of incorporating gelatin, an FDA-approved, non-immunogeneic biomaterial with biological recognition sites, as a strategy to facilitate blood vessels invasion of PVA-Tyr hydrogels and to restore the vascular supply to necrotic tissues.

METHODS

Progressively higher gelatin concentrations (0.01–5wt%) were incorporated in the PVA-Tyr network. Hydrogel physico-chemical properties and endothelial cell attachment were evaluated. Afterwards, the capability of the released VEGF and gelatin to promote vascularization was evaluated via chorioallantoic membrane (CAM) assay. VEGF-loaded PVA-Tyr hydrogels with or without gelatin (n=7) were implanted in a subcutaneous mouse model for 3 weeks. Vascularization (CD31+ cells) and cell infiltration (H&E) were evaluated. Finally, AVN was induced in 6 weeks old male piglets as previously described [2]. A transphyseal hole (3mm) was drilled and PVA-Tyr hydrogels with 1% gelatin were delivered in the defects. Piglets were euthanized after 4 weeks and microCT analysis was performed.

INTRODUCTION

Simulation plays an important role in surgical education and the ability to perfect surgical performance. Simulation can be enhanced by adding various layers of realism to the experience. Haptic feedback enhances the simulation experience by providing tactile responses and virtual reality imagery provides an immersive experience and allows for greater appreciation of three-dimensional structures. In this study, we present a proof-of-concept haptic simulator to replicate key steps of a cervical laminoplasty procedure. The technology uses affordable components and is easily modifiable so that it can be used from novice through to expert level. Custom models can be easily added ensuring the simulator can be used in a wide range of orthopaedic applications from baseline education through to day of surgery pre-operative simulation.

METHOD

We used the Unity Game Engine, the 3D Systems “Touch” Haptic Feedback Device (HFD), and a Meta Quest VR headset. Our system uses a number of complex algorithms to track the shape and provide haptic feedback of a virtual bone model. This allows for simulation of various tools including a high-speed burr, Kerrison rongeur and intraoperative X-rays.

Introduction

The health sector contributes the equivalent of 4.4% of global net emissions to the climate carbon footprint. It has been suggested that between 20% and 70% of health care waste originates from a hospital's operating room, the second greatest component of this are the textiles used, and up to 90% of waste is sent for costly and unneeded hazardous waste processing.

Waste from common orthopaedic operations was quantified, the carbon footprint calculated, and cost of disposal assessed. A discussion of the circular economy of textiles, from the author of the textile guidance to the Green Surgery Report follows.

Methods

The amount of waste generated from a variety of trauma and elective orthopaedic operations was calculated across a range of hospital sites. The waste was separated primarily into clean and contaminated, paper or plastic. The carbon footprint and the cost of disposal across the hospital sites was subsequently calculated.

Introduction

Major trauma during military conflicts involve heavily contaminated open fractures. Staphylococcus aureus (S. aureus) commonly causes infection within a protective biofilm. Lactoferrin (Lf), a natural milk glycoprotein, chelates iron and releases bacteria from biofilms, complimenting antibiotics. This research developed a periprosthetic biofilm infection model in rodents to test an Lf based lavage/sustained local release formulation embedded in Stimulin beads.

Method

Surgery was performed on adult rats and received systemic Flucloxacillin (Flu). The craniomedial tibia was exposed, drilled, then inoculated with S. aureus biofilm. A metal pin was placed within the medullary cavity and treatments conducted. Lf in lavage solutions: The defect was subject to 2× 50 mL lavage with 4 treatment groups (saline only, Lf only, Bactisure with Lf, Bactisure with saline). Lf embedded in Stimulin beads: 4 bead types were introduced (Stimulin only, Lf only, Flu only, Lf with Flu). At day 7, rats are processed for bioluminescent and X-ray imaging, and tibial explants/pins collected for bacterial enumeration (CFU).

Introduction

This study aimed to assess the relationship between preparation times and operative procedures for elective orthopaedic surgery. A clearer understanding of these relationships may facilitate list organisation and thereby contribute to improved operating theatre efficiency.

Methods

Two years of elective orthopaedic theatre data was retrospectively analysed. The hospital medical information unit provided de- identified data for 2015 and 2016 elective orthopaedic cases, from which were selected seven categories of procedures with sufficient numbers to allow further analysis - primary hip and knee replacement, spinal surgery, shoulder surgery (excluding shoulder replacement), knee surgery, foot and ankle surgery (excluding ankle replacement), Dupuytrens surgery and general orthopaedic surgery. The data analysed included patient age, ASA grade, operation, operation time, and preparation time (calculated as the time from the start of the anaesthetic proceedings to the patient's admission to Recovery, with the operating time [skin incision to skin closure] subtracted). Statistical analysis of the data was undertaken.

Introduction

Individuals with significant hip and knee trauma receive total knee (TKA) and total hip arthroplasty (THA) as definitive end-stage procedures. In Aotearoa, injury-related costs, including workers compensation, may be funded by ACC. With a steady increase of arthroplasty procedures in Aotearoa, we aim to understand the magnitude and characteristics of such procedures to inform future healthcare strategies.

Method

This is a longitudinal collaborative study from 1st January 2000 to 31st December 2020, using ACC and New Zealand Joint Registry databases. Total cost was subcategorised into social and medical cost for analysis.

INTRODUCTION

Tuberculosis (TB) is a public health challenge. However, musculoskeletal involvement represents 10–15% of all extrapulmonary cases. Upper extremity involvement is extremely rare. The slow progressive course of clinical symptoms and lack of radiological signs lead to difficulties in establishing early diagnosis. Hence, the patients who have tuberculosis of the wrist are usually misdiagnosed. We report 5 cases of tuberculosis of the wrist seen in our unit from the year 2012 to 2021.

METHODS

Cases were retrospectively evaluated on demographics, nature of history, clinical presentation, culture finding, and histopathological findings from 2012 to 2021 at our unit.

Objective

Carpal tunnel release surgery is a commonly performed procedure for alleviating symptoms of median nerve compression and restoring hand function. With pressure on theatre time these procedures are now commonly performed in a step-down out-patient facility under local anaesthetic. The choice of suture for skin closure in this procedure can impact the quality of wound healing, patient outcomes and the follow-up required however the question of the best type of suture remains unanswered. The purpose of this study was to compare the outcomes of absorbable and non-absorbable sutures using a randomised control trial design.

Methods

Eighty patients diagnosed with bilateral carpal tunnel syndrome were enrolled and underwent outpatient carpal tunnel release surgery under local anaesthetic in a staged fashion. Random number generation was used to assign each hand to receive interrupted nylon or Vicryl Rapide sutures. Pre-operative data collection included patient demographics, ASA, inflammatory conditions, smoking status as well as a Boston Carpal Tunnel Questionnaire (BCTQ) for each hand. Patients were followed up at 2 and 6 weeks after each operation and the BCTQ was repeated along with the Patient and Observer Scar Assessment Scale and the VAS score for wound discomfort. This study has approval from the DHB ethics committee, Local Iwi, HDC and ANZ Clinical Trials:ACTRN12623000100695.

Introduction

Despite the rising popularity of 1st carpometacarpal joint (CMCJ) arthrodesis as one of the surgical options for basilar thumb arthritis, the available literature on this is poor. This study aims to investigate post-operative pinch and grip strength following 1st CMCJ arthrodesis, at a minimum of 1 year follow-up. Complication rates, range of motion and patient reported scores were also evaluated.

Methods

A retrospective cohort (2012–2020) was used, which included patients who had arthrodesis performed by the Hands surgeons at Counties Manukau DHB. In a 15 minute visit, we took the measurements using our standard dynamometer and pinch gauge, and collected three questionnaires [QuickDASH, PRWHE, PEM]. For analysis, we compared our results to the preoperative measures, contralateral hand, and to a previous study on a similar cohort looking at thumb strength following trapeziectomy.

Introduction

Flexor sheath infections require prompt diagnosis, and management with intravenous antibiotics and/or surgical washout followed by physiotherapy. Complication rates as high as 38% have been reported.

Methods

A retrospective review was carried out of all patients between January 2014 and May 2021 attending with a suspected or confirmed diagnosis of flexor sheath infection. Age, gender, co-morbidities, cause of infection, management, and subsequent complications recorded.

Introduction and Aim

Quadriceps strength is crucial for physical function in patients with knee osteoarthritis (KOA). This study aimed to investigate the effect of combining blood flow restriction (BFR) with low-intensity training (LIT) on quadricep strength in patients with advanced KOA.

Methods

Patients with advanced KOA were block randomized by gender into the control or BFR group. The control group received LIT with leg press (LP) and knee extension (KE) at 30% of 1-repetition maximum (1-RM), while the BFR group underwent the same training with 70% limb occlusion.

Physical function and patient-reported outcomes were assessed up to 16 weeks.

Introduction

Day stay surgery for anterior cruciate ligament (ACL) reconstructions is an increasingly common practice and has driven clinicians to come up with postoperative pain regimes that allow same day mobilisation and a safe and timely discharge. There is a paucity of literature surrounding the use of intraosseous (IO) ropivacaine used as a Bier's block to provide both intraoperative and postoperative analgesia in lower limb surgery.

Methods

This patient blinded, pilot study randomised 15 patients undergoing ACL reconstruction to receive either IO ropivacaine 1.5 or 2.0 mg/kg; or 300 mg of ropivacaine as local infiltration (standard of care). Toxic plasma levels of ropivacaine have been defined in the literature and therefore the primary outcome for this study was arterial plasma concentration of ropivacaine as a means to determine its safety profile. Samples were taken via an arterial line at prespecified times after tourniquet deflation. Secondary outcomes that we were interested in included immediate postoperative pain scores using the visual analogue scale (VAS) and perioperative opioid equivalent consumption.

Introduction

The Oxford Unicompartmental Knee Replacement (OUKA) is the most popular unicompartmental knee replacement (UKR) in the New Zealand Joint Registry with the majority utilising cementless fixation. We report the 10-year radiological outcomes.

Methods

This is a prospective observational study. All patients undergoing a cementless OUKA between May 2005 and April 2011 were enrolled. There were no exclusions due to age, gender, body mass index or reduced bone density.

All knees underwent fluoroscopic screening achieving true anteroposterior (AP) and lateral images for radiographic assessment. AP assessment for the presence of radiolucent lines and coronal alignment of the tibial and femoral components used Inteliviewer radiographic software. The lateral view was assessed for lucencies as well as sagittal alignment.

Background

Anterior cruciate ligament (ACL) reconstruction with concomitant meniscal injury occurs frequently. Meniscal repair is associated with improved long-term outcomes compared to resection but is also associated with a higher reoperation rate. Knowledge of the risk factors for repair failure may be important in optimizing patient outcomes.

Purpose

This study aimed to identify the patient and surgical risk factors for meniscal repair failure, defined as a subsequent meniscectomy, following concurrent primary ACL reconstruction.

Objectives

Post-infective arthritis is an important sequalae of septic arthritis(SA). While total knee arthroplasty(TKA) is an effective treatment for said arthritis, previous SA brings challenges for treatment planning. Using prospectively collected data from a cohort of patients with knee SA, this study aims to determine the proportion of patients requiring eventual TKA, and risk factors of developing prosthetic joint Infection(PJI).

Methods

All cases of 1st episode knee SA from 01/01/2000 to 31/12/2020 were identified in the Auckland region. Patient records and NZJR records of all cases were searched to identify subsequent TKA. PJI following arthroplasty was identified using ICM criteria.

Univariate and multivariate analysis was performed to determine risk factors for developing PJI.

Aim

Clavicular osteotomy was described as an adjunct to deltopectoral approach for improved exposure of the glenohumeral joint. This study aims to present contemporary outcomes and complications associated with the routine use of clavicular osteotomy by a single surgeon in a regional setting within New Zealand.

Methods

A retrospective case series of patients who have undergone any shoulder arthroplasty for any indication between March 2017 to August 2022. This time period includes all patients who had clavicular osteotomy(OS) and patients over an equal time period prior to the routine use of osteotomy as a reference group (N-OS).

Oxford Shoulder Score (OSS) and a Simple Shoulder Test (STT) were used to assess functional outcomes and were compared with the reported literature. Operative times and Complications were reviewed.

Introduction

The purpose of this study was to compare implant survivorship and functional outcomes in patients undergoing reverse total shoulder arthroplasty (RTSA) for acute proximal humeral fracture (PHF) with those undergoing elective RTSA in a population-based cohort study.

Methods

Prospectively collected data from the New Zealand Joint Registry from 1999 to 2021 and identified 7,277 patients who underwent RTSA. Patients were categorized by pre-operative indication, including acute PHF (10.1%), rotator cuff arthropathy (RCA) (41.9%), osteoarthritis (OA) (32.2%), rheumatoid arthritis (RA) (5.2%) and old traumatic sequelae (4.9%). The PHF group was compared with elective indications based on patient, implant, and operative characteristics, as well as post-operative outcomes (Oxford Shoulder Score [OSS], and revision rate) at 6 months, 5 and 10 years after surgery. Survival and functional outcome analyses were adjusted by age, sex, ASA class and surgeon experience.

Introduction

The Te Whatu Ora Southern catchment area covers the largest geographical region in New Zealand (over 62,000 km2) creating logistical challenges in providing timely access to emergency neck of femur (NOF) fracture surgery. Current Australian and New Zealand guidelines recommend that NoF surgery be performed within 48 hours of presentation. The purpose of this study was to compare the outcomes for patients with NoF fractures who present directly to a referral hospital (Southland Hospital) compared to those are transferred from rural peripheral centres.

Methods

A retrospective cohort study identified 79 patients with NoF who were transferred from rural peripheral centres to a referral hospital for operative management between January 2011 to December 2020. This cohort was matched 1:1 by age and sex to patients with NoF who presently directly to the referral hospital over the same period. The primary outcome was to compare time to surgery between the groups and secondary outcomes were to compare length of hospital stay, complication rates and mortality rates at 30-days and 1-year.

Introduction

Autologous fat grafting has favourable potential as a regenerative strategy and is the current gold-standard to repair large contour defects, as needed in breast reconstruction after mastectomy and traumatic soft tissue reconstruction. Clinically, there is a limit on the volume of lipoaspirate which can be utilised to repair a soft-tissue defect. Surgical complications are the result of poor structural fidelity of lipoaspirate and graft resorption as a filling material and are hindered further by poor graft vascularisation. This study aims to develop injectable lipoaspirate-derived adipose tissue grafts with enhanced biologically and clinically-admissible structural and functional properties adopting light photocrosslinking of unmodified lipoaspirate.

Methods

Patient-derived lipoaspirate was harvested and crosslinked using novel photoinitiator and exposure to visible light (wavelength 450nm) in surgery, establishing bonds between extracellular matrix (ECM) proteins within the material. The degree of crosslinking was tuned (photoinitiator concentration, light exposure, light intensity) and covalent bond formation measured using mass spectrometry. To predict patient response, SWATH-MS was used to identify differences in patient ECM and crosslinked grafts were implanted in vivo using a subcutaneous mouse model. Functional vessel formation and resorption were quantified using micro-CT and tissue-remodelling was assessed via histology.

Aims

Using the Australian and New Zealand Hip Fracture Registry (ANZHFR) data, this study aimed to identify patient, fracture, and management factors associated with survival, mobility and residential status at 120 days. This will allow future interventions to target modifiable risk factors to improve the overall care of patients with hip fractures.

Methods

All NZ patients from 2018 – 2020 were included. Baseline demographics, management factors, and outcomes were recorded. Key outcomes were change in walking status, residential status and survival at 120 days. Univariate analysis was performed to compare differences in demographics, surgical and management factors for the key variables. Multivariate analysis was conducted to identify factors independently associated with outcomes.

Aims

Hip fracture is a common injury in the elderly. Recent studies in orthopaedic access have demonstrated inequities affecting Māori. This study aimed to compare the demographic differences between Māori and NZ Europeans with hip fractures, identify any deficiencies in initial, surgical and post op care and in outcomes.

Methods

All cases in New Zealand from 2018–2020 were included. Key outcomes included time to theatre from admission, change in walking status, residential status and survival at 120 days post fracture.

Univariate analysis compared differences in demographics, surgical and management factors between ethnicities. Key outcome comparisons were conducted using multivariate analysis to assess whether ethnicity was an independent risk factor for outcomes.

Introduction

Distal femur fractures have traditionally been stabilized with either lateral locking plate or retrograde intramedullary nail. Dual-plates and nail-plate combination fixation have the theoretical biomechanical advantage, faster union and allows patients to weight bear immediately.

The aim of this study is to compare single vs combination fixation, and evaluate outcomes and complications.

Method

We retrospectively reviewed all patients over 60, admitted to Christchurch Hospital, between 1st Jan 2016 and 31st Dec 2022, with an AO 33A/33B/33C distal femur fracture. Patient demographics, fracture characteristics, operation details, and follow up data were recorded.

Primary outcomes are union rate, ambulatory status at discharge, and surgical complications. Secondary outcomes include quality of reduction, operation time and rate of blood transfusions.

Introduction

Management of Vancouver type B1 and C periprosthetic fractures in elderly patients requires fixation and an aim for early mobilisation but many techniques restrict weightbearing due to re-fracture risk. We present the clinical and radiographic outcomes of our technique of total femoral plating (TFP) to allow early weightbearing whilst reducing risk of re-fracture.

Methods

A single-centre retrospective cohort study was performed including twenty-two patients treated with TFP for fracture around either hip or knee replacements between May 2014 and December 2017. Follow-up data was compared at 6, 12 and 24 months.

Primary outcomes were functional scores (Oxford Hip or Knee score (OHS/OKS)), Quality of Life (EQ-5D) and satisfaction at final follow-up (Visual Analogue Score (VAS)). Secondary outcomes were radiographic fracture union and complications.