BOA Annual Congress 2024

Exploring the Long-Term Efficacy of Modified Dunn Osteotomy for Severe SCFE: The Birmingham Experience

Authors: Balakumar B, Marson B, Bache CE, Birmingham Childrens Hospital

Abstract:

The Modified Dunn osteotomy is a technique used to manage severe slipped capital femoral epiphysis in children. It helps reduce slips and prevent future complications. The Birmingham experience with this technique is being evaluated in this study to determine its efficacy.

We analysed the outcomes of 57 Modified Dunn osteotomy procedures performed on 56 children by the senior author between 2006 and 2019. In April 2024, we reviewed case notes to determine arthroplasty-free survival rates, avascular necrosis rates, and other complications requiring return to theatre.

The average age at time of slip was 13.5 (SD 1.5) years. The median time to case notes review was 7.6 [IQR 10.3-13.1] years. The 5- and 10-year arthroplasty-free survival was 98.2 (95% CI 99.8-88.0%) and 94.9% (95% CI 98.8-80.2%) respectively.  During follow-up, two patients got hip replacements. One for AVN and the other for cartilage damage.

Seven patients were diagnosed with avascular necrosis during the 2-year clinical review, resulting in a 12.3% incidence rate of AVN. Two patients had labral tears, and two cases required additional surgery due to postoperative instability. Out of the 32 children without a simultaneous contralateral pin, 5 (15.6%) developed a contralateral SUFE treated with a pin in situ. Modified Dunn osteotomy offers reliable hip preservation outcomes. 15% contralateral slip risk in children.  

Ten Years of Direct Skeletal Fixation for Military Veterans; An Overview of Outcomes

Authors: Handford, C. Toderita, D. Hindle, P. Kendrew, J. Evriviades, D. Ramasamy, A. Fenton, P. Foong, D. Bull, AJ, McMenemy, L. The UK Osseointegration Group.

Abstract:

Advancements in trauma care on Operations in Iraq and Afghanistan led to 'unexpected survivors,' primarily highly motivated above-knee amputees unable to mobilise with standard prosthetics due to complex soft tissue injuries. Using LIBOR funding, 21 veterans (35 femoral residuum’s) received OGAP-OPL Direct Skeletal Fixation.

Results from two patient cohorts, the first (13 patients) with surgeries averaging 7.69 (5-10) years and the second (8 patients) treated within the last 2 years following transition to an NHS Consultant led delivery model, indicate promising outcomes.

In the established cohort low explantation rates of 4% (1/23 implants) and minimal chronic suppressive antibiotic use of 15% (2/13 patients) reassure regarding complications due to uncontrolled infection.

The incidence of fractures 11% (4/35 femoral residuum’s) from falls whilst ambulant suggests successful rehabilitation.

Favourable patient-reported outcomes and functional benefits, coupled with cost-effectiveness, advocate for continued research and potential NHS adoption.

Provision of radiation PPE across North West England’s Trauma theatres. Is it adequate? 

Authors: H Sevenoaks, L Murphy, DS Johnson, North West Orthopaedic Research Collaborative.

Aim:

To determine if the orthopaedic surgical workforce were adequately protected by radiation personal protective equipment (PPE) available in trauma theatres in NW England.

Methods:

A snapshot audit of radiation PPE provision and orthopaedic surgical workforce demographics was undertaken between January - July 2023 across 11 hospitals in NW England. Size and appropriateness of radiation PPE for surgeon use (i.e. wraparound protection, ≥0.25mm lead weight equivalence) was correlated with size requirements of the workforce using a bespoke audit tool.

Results:

284 gowns/sets of radiation PPE were evaluated, in correlation with the requirements of 417 members of the medically qualified surgical workforce (FY1 - Consultant) across North West England. For 29.4% (n=123) of surgeons in the region, there was not a single appropriately sized wrap-around gown available for them in their trauma theatres, irrespective of other users requirements. Only 31.7% (n=90) of trauma theatre radiation PPE was acceptable for surgeon use.

Regionally, there was no significant difference in access to appropriately sized standard “unisex” PPE between different workforce groups (rotating vs. permanent staff) or between male and female surgeons. No trusts had enhanced female breast protection PPE available.

Conclusions:

Provision of radiation PPE to surgeons in trauma theatres is inadequate in North West England. This project has since been undertaken in Wessex, via their trainee led research collaborative, utilising our tool to reveal similar deficiencies. BOTA are disseminating our tool across regional representatives to facilitate national improvements in this domain. We encourage all surgeons to appraise their current radiation safety measures and PPE provision and where necessary, take steps to improve it.

QIP: Local provision of ionising radiation personal protective equipment (PPE) for female orthopaedic surgeons.

Authors: Madeleine Garner, Moneet Gill, Marta Karbowiak, Ankit Desai

Background:

Use of ionising radiation is commonplace in orthopaedic theatres. The ALARA principle is important for surgeons to be familiar with to mitigate risk to the patient, themselves and their colleagues. The operating surgeon and first assistant receive a significantly higher dose of radiation compared to other theatre staff and trainees typically use more fluoroscopy than consultants. Over the last 10yrs, observational studies have demonstrated an increased prevalence in breast cancer in female orthopaedic surgeons compared to case matched urology and plastic surgeons and a simulation study demonstrated radiation exposure to the UOQ of breast tissue was significantly reduced by PPE with axillary supplements, compared to standard gowns. Subsequently, the BOA published advice, specifically regarding appropriate gowns for female orthopods. The aim of this QIP was to highlight the lack of and subsequently improve local PPE provision.

Patients and Methods:

Systematically, all gowns across 4 orthopaedic theatres were reviewed. Each gown was assessed for: style, size, lead equivalent thickness, if broken, level of axillary coverage, if “personal” and associated thyroid collar.

Results:

45 gowns and 13 thyroid shields were found. Compared to BOA recommendations: a range of sizes were available and 97.8% met the minimum thickness. 86.7% were “tabard” style, deemed UNSUITABLE for female orthopods. There were no options with high axillary protection. No female orthopod had a custom fitted gown.

An intervention was made to purchase 2 new gowns, specifically designed for female orthopods. These were “vest and skirt” style with high axillary protection, elasticated back for better conformity and embroidered to ensure exclusive use.

Conclusions:

These new gowns gave current female orthopods adequate protection. Funding constraints, occupational health policy and rotational training meant we were only able to purchase 2 “non-fitted” gowns, compromising an element of protection to allow “best-fit-for-all”. We would advise trainees check there local PPE suitability and that departments replace broken tabard gowns with skirt/vests with high axillary protection, as these can be used universally.

An Artificial Intelligence Based Approach to Musculoskeletal Acute Knee injury Triage

Authors: James Dalrymple, Dylan Mistry, Ahmed El-Sheikh, Jiri Mocicka, Mr Shehzaad Khan, Royal National Orthopaedic Hospital

Intro

Acute knee injuries and knee pain affect 25% of the adult population at any one given time in the United Kingdom (UK). In 2023, NHS England reported 230,000 of accident and emergency attendances due to acute knee injuries with an average waiting time of 16.5 weeks to see a specialist for diagnosis. We know these injuries are a significant financial and resourceful burden on our healthcare system.

In addition to early and best care, recent studies have also displayed the importance of the early diagnosis and management of knee injuries, particularly with delayed treatment of anterior cruciate ligament injuries being shown to have poorer long term outcomes (1-6).

The current pathways for these injuries through our healthcare systems are cumbersome and can often result in a delayed diagnosis and/or treatment.

There has been a huge drive and investment in artificial intelligence (AI) over the last decade. It is estimated that AI could cut annual USA healthcare costs by $150 billion by 2026. A considerable component of the cost reduction stems from adopting a proactive health management approach, expected to result in fewer hospitalisations, fewer doctor visits, and reduced treatments.

Our aim is to present a proof of concept study to assess if using AI technology to triage acute knee injuries can correctly identify patients with knee injuries who require Magnetic Resonance Imaging (MRI) prior to specialist review, ultimately streamlining the triage process.

Methods

A retrospective review was performed of patients in a single centre who had attended an acute knee clinic (AKC) and been reviewed by a senior orthopaedic surgeon. A 17 point questionnaire was designed and inputted in to an algorithm using rule-based expert system AI. This emulates the decision-making ability of a human expert, which in our case, is a consultant knee surgeon. All questions were written in a format that a lay person would be able to answer without the need of a medical examination. Answers were multiple choice or binary options. The symptoms and signs from the clinic letters were inputted in to the AI algorithm questionnaire to produce a result if the patient required an MRI scan and a provisional diagnosis. Primary outcome measure was correct identification of patients by algorithm who needed an MRI scan. Secondary outcome was the ability to make the correct diagnosis.

Results

Fifty three patients were included (30 male, 23 female); average age 29.1 (16-39). Mechanisms of injury included 28 from sport, 9 from activities of daily living, 5 from high energy and 11 from low energy. Fifty two patients went on to have an MRI scan performed as a result of the AKC consultation. Injury diagnosis from the AKC consultation were 28 ligament, 13 menisci, 2 minor fracture (osteochondral), 1 normal, 4 patellofemoral and 4 pending results. Our algorithm correctly identified 91% of patients (48) who needed a scan and identified the correct diagnosis in 81% of patients (43). Nineteen patients had dual diagnosis (i.e. ligament and menisci injury) and the AI algorithm was able to correctly identify both diagnosis in 63% of patients (12). Two patients (3.7%) were not recommended a scan from the algorithm. Further analysis showed that both patients had undisplaced posterior horn medial meniscal tears in an age group which would not routinely require initial surgical treatment. One patient (1.9%) did not have a scan, which the algorithm recommended that had a clinical diagnosis of a posterior cruciate and medial collateral ligament injury.

Discussion and Conclusion

This proof of concept study has shown that an AI based algorithm can correctly identify patients with acute knee injuries presenting to primary/secondary care that require MRI imaging with a very high sensitivity and low specificity. This could improve the efficiency and cost effectiveness of the normal patient pathway for these injuries. Ultimately resulting in quicker diagnosis and treatment of these injuries.

Despite this, our study is limited by it’s small sample size. AI technology requires thousands of data inputs in order to prove its reliability and in particular its external validity. There are also the cost implications of introducing such a system alongside the importance of maintaining patient confidentiality while utilising “big data”. 

We have shown a proof of concept in using an AI based machine learning algorithm to identify patients with acute knee injuries who require an MRI. This could be used to streamline current patient pathways to reduce cost, improve patient experience and ultimately improve patient outcomes. There is however significant hurdles to overcome prior to mainstream adoption of this technology.

Non-Selective Enhanced Recovery after Total Hip and Knee Arthroplasty: Experience of 1364 Consecutive Cases in a High-Volume Tertiary Centre

Authors: Menon D, Warren R, E Dickenson, Redfern D, Graham N, Thomas G, The Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Oswestry, Shropshire, School of Medicine, Keele University, Staffordshire

Introduction

Enhanced Recovery after Surgery (ERAS) in total joint arthroplasty improves clinical outcomes and patient satisfaction. However, current evidence is frequently based on its use in a selected healthy population with low patient numbers. This study reports outcomes of ERAS in patients undergoing lower limb arthroplasty not selected on co-morbidity status or age.

Methods

A standardised ERAS pathway was developed. Key themes included: 1. Pre-operative patient education via the ‘Joint School’ service 2. Nutritional status optimisation with high-energy drinks pre- and post-operatively 3. Standardisation of peri-operative analgesia 4. Early physiotherapy promoting post-operative mobilisation 5. Early telephone follow-up following discharge. 1364 patients undergoing ERAS following primary total hip (THA), total knee (TKA) and unicompartmental knee arthroplasty (UKA) between March 2023 and January 2024 were included. Outcomes included short-term (30-day) re-admission rate and length of stay.

Results

Individuals ranged from 19 to 96 years, with mean age 67.9 (SD: 10.6) years and mean ASA 2.1 (SD: 0.6). 91.8% cases followed the peri-operative anaesthetic protocol, and 42.5% attended Joint School pre-operatively. Mode post-operative day of mobilisation was 0 (day 0: 68.0%, day 1: 31.7%).

Similar short-term re-admission rates with significant reductions in mean LOS were noted when compared to 1076 primary THA/TKA performed between October 2022 and March 2023 6-months prior to ERAS pathway introduction (LOS: 1.9 [2.6] vs 3.9 [4.6] days, p<0.001; 30-day re-admissions: 1.4% vs 1.3%, p=0.99). Difference in mean LOS between ERAS and non-ERAS groups was greatest in individuals aged >80 years (≤60 years: 1.4 vs 3.0; 61-70 years: 1.6 vs 3.5; 71-80 years: 2.3 vs 4.0; >80 years: 3.0 vs 6.8). Individuals attending Joint School had lower mean LOS versus non-attenders (1.8 vs 2.9 days).

Discussion

This standardised ERAS protocol is safe and effective, demonstrating high early post-operative mobilisation rates and low 30-day re-admission rates. Reduced LOS associated with ERAS, due to early recovery and return to function, has enormous potential to increase bed capacity in a cost-effective manner. Pre-operative patient education appears a key driver in improving outcomes. Reduction in morbidity appear most marked in individuals of increasing age and co-morbid status, and individuals should therefore not be selected for based on these factors.

Figure 1 – Components of the ERAS Pathway

Table 1- Comparison of LOS and 30-day re-admission rates between ERAS and Non-ERAS Cohorts

WARP: Results Of The Wycombe Arthroplasty Rapid-Recovery Pathway

Authors: John McNamara, Jane Eastman, Sakis Pollalis, Aniko Frigyik, Royal Berkshire Hospital 

Background

Enhanced recovery after surgery (ERAS) protocols produce significant clinical and economic benefits in a range of surgical subspecialties. The development and implementation of such programmes are a growing area of interest in orthopaedics. Rapid recovery programmes offer a multimodal approach directed towards systemic modulation of the surgical stress response to enhance patient outcomes.

Objectives

The Wycombe Arthroplasty Rapid-Recovery Pathway was designed to streamline hip and knee joint arthroplasty to reduce time spent in hospital whilst optimising outcomes in an NHS District General Hospital. The pathway has been designed to manage patient expectations, maximise efficiency, reduce anaesthetic and surgical stress to the patient, optimise pain management and ensure timely therapy input and follow up post-discharge.

Study Design & Methods

1218 patients were admitted acorss a 2 year period to Wycombe General Hospital for elective joint replacement. 378 (31%) of pateints were admitted under the WARP pathway, 839 (69%) were admitted on the standard pathway. Baseline characteristics were similar for both cohorts. Data was collected on operation type, anaesthetic choice, physiotherpy sessions, time of mobilisation, length of stay and inpatient morbidity data.

Results

378 (31%) patients were admitted under the WARP pathway with an average length of stay of 2.2 days with 3.5 physio sessions, 60% had no day two morbidity, 11% were discharged as a day case. 43% mobilised on day 0. 839 (69%) pateints were concurrently admitted on the standard pathway, average length of stay was 3.6 days with 4.2 physio sessions, 49% had no day two morbidity. 0% were discharged on the day of surgery. 12% mobilised on day 0.

Conclusions

Our cohort study shows that the initiation of a Rapid Recovery pathway for joint arthroplasty decreases length of stay, decreases the time to first mobilisation, and decreases inpatient morbidity from joint arthroplasty in an NHS District General Hospital

Early Management of Paediatric Forearm Fractures in a Major Trauma Centre: An audit of BOAST Guidelines

Introduction:

The forearm is the most common site of fracture in the paediatric population. Recently published British Orthopaedic Association Standards for Trauma and Orthopaedics (BOAST) guidance has provided clarity in the management of these injuries. In fractures not requiring surgical intervention, early closed manipulation and casting is a suitable treatment option that avoids operative morbidity, theatre resource and reduces length of stay. The aim of this audit was to assess adherence to this guidance in the East of Scotland.

Methods:

All paediatric patients with forearm fractures were identified from East of Scotland trauma lists from 01/03/2023 to 31/08/2023. Their management was compared to the gold standard BOAST guideline: “Early Management of the Paediatric Forearm Fracture” using their inclusion and exclusion criteria.

Results:

79 patients were identified as having had a forearm fracture(s), of which 29 (37%) were excluded. Of the remaining 50, 41 patients (82%) underwent manipulation and cast application in theatre; the other 9 (18%) were treated without a general anaesthetic. The most common injuries sustained were isolated distal radius fractures (25, 50%) and dual midshaft radius and ulna fractures (13, 26%).   

Discussion:

Hospitalisation can be a distressing experience for paediatric patients. Most patients included in this cohort required at least an overnight stay in the paediatric unit and a general anaesthetic. This audit has identified scope for improvement with adherence to national guidance. We propose that a trust pathway for early reduction of these injuries could streamline the hospital route for paediatric patients whilst reducing costs.

The SU-PERiosteum – improving bone biology using novel chimeric fibulaperiosteal flap

Authors: Gagori Bandopadhyay, Steven Lo, Indira Yonjan2, Anna Rose, Giles Roditi, Colin Drury, Angus Maclean, Glasgow Royal Infirmary, Glasgow, Canniesburn Regional Plastic
Surgery and Burns Unit, Glasgow

Introduction:

The presence of pluripotent mesenchymal cells in the periosteum along with the growth factors produced or released following injury provides this tissue with an important role in bone healing. Utilising this property, vascularised periosteal flaps may increase the union rates in recalcitrant atrophic long bone non-union. The novel chimeric fibula-periosteal flap utilises the periosteum raised on an independent periosteal vessel, thus allowing the periosteum to be inset freely around the osteotomy site, improving bone biology.

Patients and methods:
Ten patients, with established non-union, underwent fibula-periosteal chimeric flaps

(2016-2022) at the Canniesburn Plastic Surgery Unit, UK. Preoperative CT angiography was performed to identify the periosteal branches. A case-control approach was used. Patients acted as their own controls, which obviated patient specific risks for non-union. One osteotomy site was covered by the chimeric periosteal flap and one without. In two patients both the osteotomies were covered using a long periosteal flap.

Results:
The mean bone gap was 7.5 cm. A chimeric periosteal flap was used in 12 of the 20 osteotomy sites. Union rate of 100% (11/11) was noted with periosteal flap osteotomies, versus those without flaps at 28.6% (2/7) (p = 0.0025). Time to union was also reduced in the periosteal flaps at 8.5 months versus 16.75 months in the control group (p = 0.023). Survival curves with a hazard ratio of 4.1, equating to a 4 times higher chance of union with periosteal flaps (log-rank p = 0.0016) was observed.

Conclusion:
The chimeric fibula-periosteal flap provides an option for atrophic recalcitrant nonunions where use of vascularised fibula graft alone may not provide an adequate biological environment for consolidation.

Single Mobility Thumb CMCJ Replacement: early results in a single surgeon cohort

Authors: Ekemini Ekpo, Sameer Gidwani, Guy's and St Thomas' NHS Foundation Trust

Objective:

Thumb carpometacarpal joint (CMCJ) osteoarthritis is a common and debilitating condition affecting 1.5% of the population. Trapeziectomy been considered the gold standard for surgical management. However, CMCJ replacement is also an option, particularly in younger, higher demand patients, as it potentially offers better preservation of pinch strength and a faster recovery.

Study Design and Methods:

A prospective cohort study design was used. All patients who underwent a Maia thumb CMCJ replacement from January 2017 to January 2024 by a single surgeon were included. Data collected included age, sex, pre-operative and post operative Patient Rated Wrist/Hand Evaluation (PRWHE), and pre- and post-operative lateral pinch strength. All complications and subsequent revisions were also recorded.

Results:

There were 35 patients in total. The mean age of patients undergoing CMCJ replacement was 59.3 years. 86% were female and 14 % were male. The mean follow up was 40 months (1-76). The mean pre-operative PRWHE score was 59.3. The mean pre-operative key pinch was 3.5kg. Postoperatively, the mean PRWHE score decreased to 15.6 while the mean key pinch score increased to 6.5kg. Four patients suffered minor complications which resolved with steroid injections.  

Conclusion:

Single mobility CMCJ replacement has demonstrated improved function and excellent pain outcomes with a low revision rates in our series. We recommend its use in active patients with minimally affected STT joints. Further studies are required that compare the outcomes of trapeziectomy versus implants, and single versus dual mobility implants, both in terms of complications and longevity. 

What are the demographics and ethnicity of patients who have THR/TKR at SWLEOC: Do interventions and outcomes vary by age, sex, ethnicity or social deprivation?

Author: Olusegun Ayeko, University Hospitals Plymouth

Aims:
The aim of this study is to describe the demographics of patients undergoing hip and knee replacement at The South West London Elective Orthopaedic Centre (SWLEOC) and examine whether they are associated with 1-year Patient Reported Outcome Measures and the change from baseline.

Patients:
SWLEOC patients who underwent primary Total Hip or Knee joint replacement during the whole calendar years 2019 and 2021.

Methods:
A retrospective analysis of prospectively collected data from SWLEOC was obtained electronically. The primary outcome measures were changes in Oxford Hip and Knee Scores, EQ-5D Index and EQ-5D-VAS scores from baseline to 1-year. The secondary outcomes were time on waiting list and length of stay. We calculated associations of age, sex, ethnicity and deprivation with baseline, 1-year and the change in Patient Reported Outcome Measures using multivariable regression.

Results:
There were 2,502 Total Hip Replacements and 2,763 Total Knee Replacements 2411 and 2611 patients respectively. Patients younger than 60 years, female sex, South Asian ethnicity and in the most deprived decile had lower baseline and 1-year Oxford Hip and Knee Scores. Changes in PROM score and waiting list time did not vary between patient demographic and ethnicity groups.

Conclusion:
Age, sex, ethnicity and deprivation are intertwined in health behaviour and outcomes, with negative associations observed. It must be recognised that detrimental biases and risks exist for these groups.

Tönnis angle and Acetabular depth ratio: predictors of dislocation following hemiarthroplasty for hip fracture

Authors: Vatsal Gupta, Mohamed Yassin, Darryl Ramoutar, Thomas Hunter

Background:

Despite efforts to mitigate possible modifiable risk factors, dislocations following hemiarthroplasty for hip fracture still occur, with reported incidence rates ranging from 1.5 to 11%. The aim of this study was to investigate whether acetabular dysplasia is a significant contributing factor to dislocation, and since non-modifiable, whether it should affect patient selection for this treatment option.

Methods:

This is a multicentre nested case-control study of patients treated at 2 separate centres over a 10-year period from January 2011 to December 2020. All cases of hemiarthroplasty dislocation following hip fracture were identified from local databases, and 4 random controls were selected for every case. Tönnis angle (TA) and Acetabular-depth-ratio (ADR) was measured on the injured side using AP pelvis radiographs. Patients with TA > 10° and/or ADR < 250 were considered to have abnormal acetabular morphology.

Results:

35 cases of dislocation were identified and 140 random controls were selected. Cases of dislocation had a larger mean TA (8.8° vs. 5.5°, p < 0.001) and lower mean ADR (254 vs. 289, p < 0.001) than controls. 20 out of 35 (57%) cases were considered to have abnormal acetabular morphology, compared to 19 out of 140 (14%) controls. The odds of dislocation is 8.5 times greater (odds ratio = 8.49, 95%CI = 3.73, 19.39) in patients with abnormal TA and/or ADR.

Conclusions:

This study demonstrates that TA > 10° and ADR < 250 are useful criteria to identify patients at greater risk of hip hemiarthroplasty dislocation due to acetabular dysplasia. Special consideration to preoperative planning should be taken in these patients. Future research should focus on methods to minimise risk in this subset of patients, including evaluating total hip arthroplasty with dual mobility component vs hemiarthroplasty.

Hyponatraemia in lower limb arthroplasty increases length of stay but reliably corrects on follow-up bloods. Can we safely discharge patients earlier?

Authors: Alexander Denning, Rabia Iqbal, Julia Craggs, Ffion Byrn, Toby Briant-Evans

Introduction

Postoperative hyponatraemia is common in elective orthopaedics, however patient management guidelines are lacking. Literature on hyponatraemia’s effect on length of stay (LOS) is limited and there is paucity of data on follow-up bloods. We analysed LOS and follow-up bloods aiming to identify trends which may aid our discharge decisions in elective orthopaedic patients with hyponatraemia.

Methods

We performed retrospective data collection over 6 months in 2023 at 2 hospitals performing lower limb arthroplasty. We collated the patient demographics, pre, post-operative and follow-up sodium levels performed following discharge.

Results

We included 456 patients. 214 had TKR, 203 had THR and 39 had UKR. 25% patients had postoperative hyponatraemia, of those 70% were mild, 26% were moderate, 4% were severe. The groups were matched for mean age (hyponatraemia 70, normal 69) and mean ASA (hyponatraemia 2.8,  normal 2.6). Our data showed the LOS for hyponatraemic patients was 3.6 days compared to 2.3 in those with normal postoperative sodium. 25% of hyponatraemic patients had follow-up outpatient bloods, 95% showed an increase in sodium, with an average increase of 4.5mmoL. 90% returned back to their baseline hyponatraemia level.

Conclusion

We demonstrate that LOS in patients with postoperative hyponatraemia is over a 1 day more than patients with normal postoperative sodium. We also demonstrated a reliable correction in sodium levels once discharged. We feel we can use this data to implement guidelines to discharge patients with postoperative hyponatraemia sooner, taking strain off the service and allowing patients to return to their home comforts earlier.