header advert
Results 1 - 15 of 15
Results per page:
Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 74 - 74
23 Feb 2023
Hunter S Baker J
Full Access

Acute Haematogenous Osteomyelitis (AHO) remains a cause of severe illness among children with the possibility of long-term consequences for growth and development. Previous research on sequelae from AHO rarely considers outcomes more than two years following treatment. This study aims to establish the quality of life of patients diagnosed with AHO in childhood up to 13 years after diagnosis, evaluating the impact on social, emotional, physical, and school function.

Children treated for AHO between 2008-2018 at a tertiary referral centre in New Zealand were identified. PedsQL™ questionnaires were conducted via phone with either the child or primary caregiver and responses analysed.

40 patients met inclusion criteria, were contactable by phone, and consented to participate. The mean age was 7 years (range 0-15) and most were female (60%). Health related quality of life (HRQOL) was scored as a percentage with most participants scoring >80% (n=27). Those who do experience reduced quality of life following treatment for AHO were likely to complain of pain, stiffness, or anxiety. The impact of significant childhood illness on mental health was not adequately captured by the PedsQL™ but was highlighted in qualitative feedback.

We conclude that the majority of children treated for AHO reported excellent health-related quality of life up to 13 years following treatment although an negative impact on mental health was reported using qualitative analysis. A refined scoring system is needed to assess the long-term impact of musculoskeletal infection.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 73 - 73
23 Feb 2023
Hunter S Baker J
Full Access

Acute Haematogenous Osteomyelitis (AHO) remains a cause of severe illness among children. Contemporary research aims to identify predictors of acute and chronic complications. Trends in C-reactive protein (CRP) following treatment initiation may predict disease course. We have sought to identify factors associated with acute and chronic complications in the New Zealand population.

A retrospective review of all patients <16 years with presumed AHO presenting to a tertiary referral centre between 2008-2018 was performed. Multivariate was analysis used to identify factors associated with an acute or chronic complication. An “acute” complication was defined as need for two or more surgical procedures, hospital stay longer than 14-days, or recurrence despite IV antibiotics. A “chronic” complication was defined as growth or limb length discrepancy, avascular necrosis, chronic osteomyelitis, pathological fracture, frozen joint or dislocation. 151 cases met inclusion criteria. The median age was 8 years (69.5% male). Within this cohort, 53 (34%) experienced an acute complication and 18 (12%) a chronic complication.

Regression analysis showed that contiguous disease, delayed presentation, and failure to reduce CRP by 50% at day 4/5 predicted an acutely complicated disease course. Chronic complication was predicted by need for surgical management and failed CRP reduction by 50% at day 4/5. We conclude that CRP trends over 96 hours following commencement of treatment differentiate patients with AHO likely to experience severe disease.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 105 - 105
23 Feb 2023
He W Masters R Baker J
Full Access

The minimisation of errors incurred during the learning process is thought to enhance motor learning and improve performance under pressure or in multitasking situations. If this is proven in surgical skills learning, it has the potential to enhance the delivery of surgical education. We aimed to compare errorless and errorful learning using the high-speed burr.

Medical students (n=30) were recruited and allocated randomly to an errorless or errorful group. The errorless learning group progressively learnt tasks from easy to difficult on cedar boards simulating bone. The errorful learning group also progressed through the same tasks but not in order of difficulty.

Transfer tasks assessed students’ performance of cervical laminoplasty on saw bone models to assess their level of learning from previous stages. During transfer task 2, students completed the procedure under time pressure and in the presence of distractors, in order to simulate real-life stressors in theatre. Accuracy, precision and safety of the procedure were scored by expert opinions from spine surgeons blinded to the grouping of the participants.

Both errorless and errorful learners demonstrated improvements in performance with increasing amounts of practice (demonstrated by the decreased time taken for the task as well as improvement in accuracy of the cuts (depth, width and smoothness). The performance of both groups was not impaired by the incorporation of a secondary task which required participants to multitask. No statistically significant difference in performance was noted between the two groups.

In contrast to previous research, there was no significant difference between errorless or errorful learning to develop skills with a high-speed, side-cutting burr. In both groups, practical learning during the session has led to improvement in overall performance with the burr relevant to cervical laminoplasty.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 42 - 42
23 Feb 2023
Bekhit P Ou C Baker J
Full Access

Sarcopenia has been observed to be a predictor of mortality in international studies of patients with metastatic disease of the spine. This study aimed to validate sarcopenia as a prognostic tool in a New Zealand setting. A secondary aim of this study was to assess the intra-observer reliability of measurements of psoas and vertebral body cross sectional areas on computed tomography imaging.

A cohort of patients who had presented to Waikato Hospital with secondary neoplasia in the spinal column from 2014 to 2018 was selected. Cross sectional psoas and vertebral body areas were measured at the mid-pedicle L3 level, followed by calculation of the psoas to vertebral body cross sectional area ratio. Psoas to vertebral body cross sectional area ratio was compared with survivorship. The strength of the correlation between sarcopenia and survivorship was compared with the correlation between serum albumin and survivorship, as well as the correlation between the Metastatic Spine Risk Index (MSRI) and survivorship.

A total of 110 patients who received operative (34) and non-operative (76) were included. The results demonstrate that psoas to vertebral body cross sectional area ratio is not statistically significantly correlated with survivorship (p=0.53). Serum albumin is significantly correlated with survivorship (p<0.0001), as was the MSRI. There is good intra-observer and inter-observer reliability for measurements of psoas to vertebral body cross sectional area.

This study failed to demonstrate the utility for the psoas to vertebral body cross sectional area ratio that other studies have demonstrated in estimating survivorship. Serum albumin levels remain a useful prognostic indicator in patients with secondary tumours in the vertebral column.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 43 - 43
23 Feb 2023
Bekhit P Coia M Baker J
Full Access

Several different algorithms attempt to estimate life expectancy for patients with metastatic spine disease. The Skeletal Oncology Research Group (SORG) has recently developed a nomogram to estimate survival of patients with metastatic spine disease. Whilst the use of the SORG nomogram has been validated in the international context, there has been no study to date that validates the use of the SORG nomogram in New Zealand. This study aimed to validate the use of the SORG nomogram in Aotearoa New Zealand.

We collected data on 100 patients who presented to Waikato Hospital with a diagnosis of spinal metastatic disease. The SORG nomogram gave survival probabilities for each patient at each time point. Receiver Operating Characteristic (ROC) Area Under Curve (AUC) analysis was performed to assess the predictive accuracy of the SORG score. A calibration curve was also performed, and Brier scores calculated. A multivariate Cox regression analysis was performed.

The SORG score was correlated with 30 day (AUC = 0.72) and 90-day mortality (AUC = 0.71). The correlation between the SORG score and 90-day mortality was weaker (AUC = 0.69). Using this method, the nomogram was correct for 79 (79%) patients at 30-days, 59 patients (59%) at 90-days, and 42 patients (42%) at 365-days. Calibration curves demonstrated poor forecasting of the SORG nomogram at 30 (Brier score = 0.65) and 365 days (Brier score = 0.33). The calibration curve demonstrated borderline forecasting of the SORG nomogram at 90 days (Brier score = 0.28). Several components of the SORG nomogram were not found to be correlated with mortality.

In this New Zealand cohort the SORG nomogram demonstrated only acceptable discrimination at best in predicting life 30-, 90- or 356-day mortality in patients with metastatic spinal disease.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 63 - 63
23 Feb 2023
Tan R Jadresic M Baker J
Full Access

Māori consistently have poorer health outcomes compared to non-Māori within Aotearoa. Numerous worldwide studies demonstrate that ethnic minorities receive less analgesia for acute pain management. We aimed to compare analgesic management of a common orthopaedic injury, tibial shaft fracture, between Māori and non-Māori.

A retrospective cohort study from January 1st, 2015, to December 31st 2020 inclusive. Eligible patients were 16-65 years old and had isolated closed tibial shaft fractures. 104 patients were included in the study, 48 Māori and 56 Non-Māori. Baseline demographics were similar between the 2 cohorts. The primary outcome measure was type of analgesia charted on the ward. Secondary outcome measures were pre-hospital medications given, pain scores on arrival to the emergency department (ED) and the ward, time to analgesia in ED and type of analgesia given in ED. Statistics were calculated using Fisher's exact test, Pearson's chi-squared test or Wilcoxson's rank sum test as appropriate

No statistically significant differences were found in opiates or synthetics charted to Māori vs Non-Māori (83% vs 89% and 77% vs 88% respectively), opiates given in ED, time to analgesia in ED or ED and ward arrival pain scores. Of statistical significance is that Māori were less likely to receive pre-hospital medication compared to Non-Māori (54% vs 80% respectively, p=0.004)

Māori were significantly less likely to receive pre-hospital pain medication compared to Non-Māori. However no other statistically significant findings were found when comparing pain scores, time to analgesia or type of pain relief charted for Māori vs non-Māori.

The reasons for Māori receiving significantly less prehospital medication were not explored in this study and further investigation is required to reduce the bias that exists in this area.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 5 - 5
23 Feb 2023
Coia Jadresic M Baker J
Full Access

Numerous prediction tools are available for estimating postoperative risk following spine surgery. External validation studies have shown mixed results. We present the development, validation, and comparative evaluation of novel tool (NZSpine) for modelling risk of complications within 30 days of spine surgery.

Data was gathered retrospectively from medical records of patients who underwent spine surgery at Waikato Hospital between January 2019 and December 2020 (n = 488). Variables were selected a priori based on previous evidence and clinical judgement. Postoperative adverse events were classified objectively using the Comprehensive Complication Index. Models were constructed for the occurrence of any complication and significant complications (based on CCI >26). Performance and clinical utility of the novel model was compared against SpineSage (https://depts.washington.edu/spinersk/), an extant online tool which we have shown in unpublished work to be valid in our local population.

Overall complication rate was 34%. In the multivariate model, higher age, increased surgical invasiveness and the presence of preoperative anemia were most strongly predictive of any postoperative complication (OR = 1.03, 1.09, 2.1 respectively, p <0.001), whereas the occurrence of a major postoperative complication (CCI >26) was most strongly associated with the presence of respiratory disease (OR = 2.82, p <0.001).

Internal validation using the bootstrapped models showed the model was robust, with an AUC of 0.73. Using sensitivity analysis, 80% of the model's predictions were correct. By comparison SpineSage had an AUC of 0.71, and in decision curve analysis the novel model showed greater expected benefit at all thresholds of risk.

NZSpine is a novel risk assessment tool for patients undergoing acute and elective spine surgery and may help inform clinicians and patients of their prognosis. Use of an objective tool may help to provide uniformity between DHBs when completing the “clinician assessment of risk” section of the national prioritization tool.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_2 | Pages 55 - 55
10 Feb 2023
Goddard-Hodge D Baker J
Full Access

Reduced cervical spine canal AP diameter is linked to the development of spinal cord injury and myelopathy. This is of particular interest to clinicians in New Zealand, given a unique socio-ethnic make-up and prevalent participation in collision sport. Our study builds upon previous unpublished evidence, by analysing normal cervical spine CT scans to explore morphological differences in the sub-axial cervical spine canal, between New Zealand European, Māori and Paciāca individuals.

670 sub-axial cervical vertebrae (C3-C7) were analysed radiographically using high resolution CT trauma scans, showing no acute pathology with respect to the cervical spine. All measurements were made uPlising mulP-planar reconstruction software to obtain slices parallel to the superior endplate at each vertebral level. Maximal canal diameter was measured in the AP and transverse planes. Statistical analysis was performed using analysis of variance (ANOVA).

We included 250 Maori, 250 NZ European and 170 Paciāca vertebrae (455 male, 215 female). Statistically and clinically signiācant differences were found in sagittal canal diameter between all ethnicities, at all spinal levels. NZ European vertebrae demonstrated the largest AP diameter and Paciāca the smallest, at all levels. Transverse canal diameter showed no signiācant difference between ethnicities, however the raatio of AP:transverse diameter was signiācantly different at all spinal levels except C3. Subjective morphological differences in the shape of the vertebral canal were noted, with Māori and Paciāca patients tending towards a flatter, curved canal shape.

A previous study of 166 patients (Coldham, G. et al. 2006) found cervical canal AP diameter to be narrower in Māori and Paciāca patients than in NZ Europeans. Our study, evaluating the normal population, conārms these differences are likely reflecPve of genuine variation between these ethniciPes. Future research is required to critically evaluate the morphologic differences noted during this study.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_9 | Pages 41 - 41
1 May 2017
Staunton P Baker J Green J Devitt A
Full Access

Background The internet is an increasingly utilised resource for accessing information regarding a variety of heath conditions. YouTube is a popular video sharing platform used to both seek and distribute information online.

Materials & Methods

A search for ‘scoliosis’ was carried out using YouTube's search engine and data was collected on the first fifty videos returned. A JAMA score (to determine currency, authorship, source and disclosure) and scoliosis specific score (that measures the amount of information on the diagnosis and treatment options as devised by Mathur et al in 2005; scored 0–32) was recorded for each video to measure quality objectively. Additionally the number of views, number of comments and feedback positivity was documented for each. Data analysis was conducted using R 3.1.4/R Studio 0.98 with control for the age of each video in analysis models.

Results

The average number of views per video was 71,152 with an average length of 7 minutes 32 seconds. Thirty six percent of the videos fell under the authorship category of personal experience. The average JAMA score was 1.32/4 and average scoliosis specific score was 5.38/32. There was a positive correlation between JAMA score and number of views P=0.003. However in contrast there was a negative correlation between scoliosis specific score and number of views P=0.01.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 159 - 159
1 Sep 2012
Baker J Green J Synnott K Stephens M Poynton A Mulhall K
Full Access

Background

The internet has revolutionized the way we live our lives. Over 60% of people nationally now have access to the internet. Healthcare is not immune to this phenomenon. We aimed to assess level of access to the internet within our practice population and gauge the level of internet use by these patients and ascertain what characteristics define these individuals.

Method

A questionnaire based study. Patients attending a mixture of trauma and elective outpatient clinics in the public and private setting were invited to complete a self-designed questionnaire. Details collected included basic demographics, education level, number of clinic visits, history of surgery, previous clinic satisfaction, body area affected, whether or not they had internet access, health insurance and by what means had they researched their orthopedic complaint.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 183 - 183
1 Sep 2012
Baker J Mullett H
Full Access

Purpose

The aim of this study was to report the outcomes of a series of patients with clavicle fracture non-union who had undergone open reduction and internal fixation using a contoured locking plate without the use of distant bone graft.

Methods

Patients were identified using the hospital database. Records were reviewed to determine basic demographics, operative findings, and radiological outcome. Patients were contacted and details about initial injury and treatment, and return to work and sport were recorded. Disabilities of Arm, Shoulder and Hand (DASH) for both operated and non-operated shoulders were completed.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 166 - 166
1 Sep 2012
Baker J Walsh P Mulhall K
Full Access

Introduction

Matrix metalloproteinases (MMP) play a key role in cartilage degradation in osteoarthritis. Statins are a potential suppressor of MMPs. The aim of this research was to assess the efficacy of Pravastatin in suppressing MMP gene and protein expression in an in vitro model.

Methods

We stimulated normal human chondrocytes with IL-1b for 6 hours to induce MMP expression and then treated with Pravastatin (1, 5 & 10 mM) for a further 18 hours. Cells stimulated with IL-1b but not treated with Pravastatin served as controls. Real-time PCR was used to assess expression of MMP-3 and MMP-9 mRNA. MMP enzyme activity was assessed using a fluorescent MMP-specific substrate. Staistical analysis was performed using ANOVA.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XVII | Pages 50 - 50
1 May 2012
Baker J Byrne D Walsh P Mulhall K
Full Access

Introduction

Local anaesthetic has been reported to have a detrimental effect on human chondrocytes both in vitro and in vivo. Magnesium, an NMDA-receptor antagonist, may be an alternative intra-articular analgesic agent following arthroscopy. We aimed to report the dose response effect of commonly used local anaesthteitc on chondrocyte viability and also report on the effect of adding magnesium to local anaesthetic.

Methods

Human chondrocytes were grown under standard conditions. Cells were exposed to either lignocaine (0.5, 1, 2%), levobupivacaine (0.125, 0.25, 0.5%), bupivacaine (0.125, −.25, 0.5%) or ropivacaine (0.1875, 0.375, 0.75%) for 15 minutes. Cells were also exposed to a local anesthetic agent with the addition of magnesium (10, 20, or 50%). Cells exposed to media or saline served as controls. The MTS assay was used to assess cell viability 24-hours after exposure.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XVIII | Pages 20 - 20
1 May 2012
Baker J Walsh P Mulhall K
Full Access

Introduction

Local anaesthetic has been reported to have a potentially detrimental effect on human chondrocytes both in vitro and in vivo. Due to chondroproliferative effects, magnesium may be an alternative intra-articular analgesic agent following arthroscopy. We aimed to examine the dose response effect of commonly used local anaesthetics on chondrocyte viability and also to report on the effect of adding magnesium to the local anesthetic agent.

Methods

Human chondrocytes were grown under standard culture conditions. Cells were exposed to either lignocaine (0.5, 1, 2%), levobupivacaine (0.125, 0.25, 0.5%), bupivacaine (0.125, 0.25, 0.5%) or ropivacaine (0.1875, 0.375, 0.75%) for 15 minutes. Cells were also exposed to a local anesthetic agent with the addition of magnesium (10, 20, or 50%). Cells exposed to culture media or saline served as controls. The MTS assay was used to assess cell viability 24 hours after exposure. One-way ANOVA were used to test for statistical significance.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_II | Pages 145 - 145
1 May 2011
Lui D Baker J Devitt B Kiely P Synnott K Poynton A
Full Access

Introduction: Definitions of surgical site infections are based on those of CDC, published in 1992. Infections that occur within 30 days of surgery are classified as:

Superficial – involves only the skin or subcutaneous tissue.

Deep – involves the deep tissues (i.e. fascial and muscle layers).

Organ / space – where part of the anatomy is manipulated during surgical procedure and within one year if an implant is in place.

Between 2006 and 2008 the infection rates of the National Spinal Surgery Unit have been closely monitored as part of a multidisciplinary team approach led in large part by the Infection Control Team. A surveillance protocol was developed. They prospectively monitored every spinal surgery patient as part of a infection control data base. Biographical and medical history data were collated including diabetic status, prophylactic antibiotic use and surgical procedure. Information was collated and feedback on changes was examined by audit which was conducted regularly.

Methods: As part of the routine audit of the NSSU department a deep infection rate of 3.5% was noted in 2006. The infection control team set up a specific unit to co ordinate surveillance of NSSU. We describe simple and evidence based protocols for prophylactic antibiotic use in conjunction with the Pharmacy, Infection Control and Microbiology department was organised in running with international standards. Furthermore, surgical, nursing and paramedical staff, involved in the NSSU, were swabbed routinely. New rigid guidelines were introduced in theatre for draping patients including the addition of topical alcohol use and 8 minute minimum bethidine drying time.

Results: From 2006, deep infection rate was 3.5%. This was followed by a 2.49% in 2007 and 1.79% in 2008. Of note the deep infection rate in 2004 was 5.5% (2 years prior to implementation of Infection Control protocols).

Conclusions: The National Spinal Surgery Unit was able to decrease the deep infection rate by 51% over 3 years by the implementation of careful prospective surveillance by a multidisciplinary team involving an Infection Control team which monitored the NSSU prospectively as well as co-ordinating changes in the protocol of antibiotic use as well peri-operative sterile techniques. We describe simple protocols which can be easily used in other institutions to aid in the mitigation of deep spinal surgical infection.