Aim

To evaluate whether sonication of implant material and subsequent culturing add clinical relevance to culturing of tissue biopsies for improved antibiotic treatment in treatment of bone and joint infection.

Background

An improved understanding of intervertebral disc (IVD) structure and function is required for treatment development. Loading induces micro-fractures at the interface between the nucleus pulposus (NP) and the annulus fibrosus (AF), which is hypothesized to induce a cascade of cellular changes leading to degeneration. However, there is limited understanding of the structural relationship between the NP and AF at this interface and particularly response to load. Here, X-ray scattering is utilised to provide hierarchical morphometric information of collagen structure across the IVD, especially the interface region under load.

Aim

One of the surgical therapeutic options for periprosthetic joint infection (PJI) includes debridement, antibiotics, and implant retention (DAIR). Prognostically favorable criteria for DAIR include short duration of symptoms, stable implant, pathogen susceptible to a ‘biofilm-active’ antimicrobial agent, and intact soft-tissue conditions. Despite this, there is a proportion of failures after DAIR, possibly because the duration of infection is underestimated. With the hypothesis that the duration of infection correlates with the bacterial load, and hence, the bacterial load is associated with failure after DAIR, we aimed to investigate the association of bacterial load in the sonication fluid of mobile parts and clinical outcome after DAIR.

Introduction

Fracture related infection (FRI) is a challenging complication to manage in an orthoplastic setting. Consensus guidelines have been created to standardise the diagnosis of FRI and comprise confirmatory and suggestive criteria. In this study, the aim is to assess the diagnostic criteria and management of FRI with a particular focus on soft tissue reconstruction.

Aim

The time to onset of symptoms after fracture fixation is still commonly used to classify fracture-related infections (FRI). Early infections (<2 weeks) can often be treated with debridement, systemic antibiotics, irrigation, and implant preservation (DAIR). Late infections (>10 weeks) typically require implant removal as mature, antibiotic-tolerant biofilms have formed. However, the recommendations for delayed infections (2–10 weeks) are not clearly defined. Here, infection healing and bone healing in early and delayed FRI is investigated in a rabbit model with a standardized DAIR procedure.

Purpose of study and background

Psychological factors are considered to play a role in development and maintenance of chronic low back pain (CLBP). Stress or anxiety can change pain sensitivity; however, this has predominantly been studied in healthy individuals with limited work in individuals with musculoskeletal pain. The objective of this study was to quantify the effect of acute exposure to a psychosocial stressor on mechanical pain sensitivity in individuals with and without CLBP.

Introduction

The purpose of this study was to analyse the efficacy and complications associated with the use of Calcium Sulphate synthetic bone graft in a paediatric population. There are no published articles on the use in children.

There is no agreement as to the superiority or specific indications for cast treatment, percutaneous pinning or open fracture fixation for Bennett's fractures of the thumb metacarpal. We undertook this study to compare the outcomes of treatment for patients treated for Bennett's fracture in the medium term.

We reviewed 33 patients treated in our unit for a bennett's fracture to the thumb metacarpal with closed reduction and casting. Each patient was matched with a patient treated surgically. Patients were matched for sex, age, Gedda grade of injury and hand dominance. Patients were reviewed at a minimum of 5-years and 66-patients were reviewed in total. Patients were examined clinically and also asked to complete a DASH questionnaire score and the brief Michigan hand questionnaire. Follow up plain radiographs were taken of the thumb and these were reviewed and graded for degenerative change using the Eaton-Littler score.

Sixty-six patients were included in the study, with 33 in the surgical and non-surgical cohorts respectively. The average age was 39 years old. In each cohort, 12/33 were female, 19/33 were right-handed with 25% of individuals injuring their dominant hand. In each coort there were 16 Grade 1 fractures, 4 Grade 2 and 13 Grade 3 fractures. There was no difference between the surgically treated and cast-treatment cohorts of patients when radiographic arthritis, pinch grip, the brief Michigan Hand Questionnaire and pain were assessed at final review. The surgical cohort had significantly lower DASH scores at final follow-up. There was no significant difference in the normalised bMHQ scores.

Our study was unable to demonstrate superiority of either operative or non-operative fracture stabilization. Patients in the surgical cohort reported superior satisfaction and DASH scores but did not demonstrate any superiority in any other objectively measured domain.

Surgical management of acetabular fractures in older patients remains controversial. The purpose of this study is to compare outcomes of primary THA with outcomes after THA for acute acetabular fractures (aTHA) as well as outcomes following delayed THA (dTHA) following prior acetabular fracture.

We analyzed data from a large, national administrative claims database containing diagnostic, procedural, and demographic records from over 157 million patients. We identified all patients undergoing primary total hip arthroplasty THA continuously enrolled in the database at least 2 years prior and after the index procedure. Patients with an initial diagnostic code for acetabular fracture occurring the same day as the THA were classified as acute acetabular fractures. Patients with an initial acetabular fracture diagnostic code occurring at least 6 months before THA were classified as chronic acetabular fractures. The comparator group was patients undergoing THA with no history of acetabular fracture. There were 426,734 patients undergoing primary THA, 235 patients undergoing aTHA and 1,255 patients undergoing dTHA.

Patients with an aTHA had higher complication rates, including revisions (9.8% vs 5.6%,), dislocations (8.9% vs 6.4%), and periprosthetic fracture (5.1% vs 2.3%) compared to dTHA. After adjusting for age, sex, region, and comorbidities, receiving an aTHA increased the odds of revision (OR = 3.65 [95% CI: 2.30–5.49]), dislocation (OR = 4.09 [95% CI: 2.53–6.27]), and periprosthetic fracture (OR = 4.29 [95% CI: 2.26–7.36]) compared to primary THA. Receiving a dTHA significantly increased the odds of revision (adjusted OR = 1.80 [95% CI: 1.40–2.27]), dislocation (adjusted OR = 2.50 [95% CI: 1.97–3.13]), and periprosthetic fracture (adjusted OR = 1.99 [95% CI: 1.34–2.83]) compared to primary THA.

Patients undergoing aTHA in the treatment of an acetabular fracture have significantly increased rates of revision, periprosthetic fracture, and dislocation compared to dTHA and primary THA.

The aim of this investigation is to firstly quantify the burden of disease, and secondly qualify the organisms being cultured during debridement to establish their sensitivities to available antibiotics. This study will also look at the concomitant burden of Human Immunodeficiency Virus (HIV) and Diabetes Mellitus (DM) in cases of hand sepsis, to establish whether these two disease processes require special consideration and treatment tailoring.

The method employed to collect the data will be retrospective collection of patient information, using random sampling. Included patients will be adult patients who undergo debridement and have a sample registered on the National Health Laboratory System (NHLS). The daily intake sheet will be used to collect patients details and these details will then be used to collect results of intra-operative specimens using the NHLS. These patient details will also be used to check patients’ HIV results and HBA1c (Glycated Haemoglobin A1c) results.

Majority of the specimens revealed Methicillin Sensitive Staphylococcus Aureus (MSSA), with a reassuringly low rate of Methicillin Resistant Staphylococcus Aureus (MRSA) when compared to international data. The yield of patients tested for HIV or DM was lower than expected, despite this being the standard of care.

The projected impact of this study will be assessment of the current burden of disease and then clarification of our current management strategy, in order to assess if it would be possible to change to a more cost-effective antibiotic with a narrower spectrum of bacteria coverage. The potential exists to not only implement cost saving measures, but also promote antibiotic stewardship by decreasing the practice of empiric broad-spectrum antibiotic use.

The purposes of this study were to report the accuracy of stem anteversion for Exeter cemented stems with the Mako hip enhanced mode and to compare it to Accolade cementless stems.

We reviewed the data of 25 hips in 20 patients who underwent THA through the posterior approach with Exeter stems and 25 hips in 19 patients with Accolade stems were matched for age, gender, height, weight, disease, and approaches. There was no difference in the target stem anteversion (20°–30°) between the groups. Two weeks after surgery, CT images were taken to measure stem anteversion.

The difference in stem anteversion between the plan and the postoperative CT measurements was 1.2° ± 3.8° (SD) on average with cemented stems and 4.2° ± 4.2° with cementless stems, respectively (P <0.05). The difference in stem anteversion between the intraoperative measurements and the postoperative CT measurements was 0.75° ± 1.8° with Exeter stems and 2.2° ± 2.3° with Accolade stems, respectively (P <0.05).

This study demonstrated a high precision of anteversion for Exeter cemented stems with the Mako enhanced mode and its clinical accuracy was better with the cemented stems than that with the cementless stems. Although intraoperative stem anteversion measurements with the Mako system were more accurate with the cemented stems than that with the cementless stem, the difference was about 1° and the accuracy of intra-operative anteversion measurements was quite high even with the cementless stems. The smaller difference in stem anteversion between the plan and postoperative measurements with the cemented stems suggested that stem anteversion control was easier with cemented stems under the Mako enhanced mode than that with cementless stems.

Intraoperative stem anteversion measurement with Mako total hip enhanced mode was accurate and it was useful in controlling cemented stem anteversion to the target angle.

Aim

Debridement, antibiotics, and implant retention (DAIR) is a viable treatment option for acute periprosthetic joint infections (PJI). The landmark DATIPO trial of Bernard et al. concluded that six weeks is not non-inferior to 12-week antibiotic therapy for DAIR. However, it is unknown if suppressive antibiotic treatment (SAT) would improve patient outcomes. Therefore, our study aims to evaluate the utility of SAT after 12 weeks of therapy.

Background

Chronic low back pain (CLBP) is the leading cause of disability worldwide. Immersive virtual reality (IVR) can be delivered using head mounted display (HMD) to interact with 3D virtual environment (VE). IVR has shown promising results in management of chronic pain conditions, using different mechanisms (e.g., exposure to movement and distraction). However, it has not been widely tested for CLBP. Future development of IVR intervention needs inputs from gatekeepers to determine key considerations, facilitators and barriers. This qualitative study aimed to explore views and opinions of physiotherapists about IVR intervention for adults with CLBP.

Abstract

In the Unites States, approximately 24% of people undergoing primary total knee or total hip arthroplasty (TKA, THA) are chronic opioid users pre-operatively. Few studies have examined the incidence of opioid use prior to TKA/THA and whether it predicts outcomes post-surgery in the Australian context. The aim was to determine: (i) the proportion of TKA and THA patients who use opioids regularly (daily) pre-surgery; (ii) if opioid use pre-surgery predicts (a) complication and readmission rates to 6-months post-surgery, (b) patient-reported outcomes to 6-months post-surgery.

A retrospective cohort study was undertaken utilising linked individual patient-level data from two independent databases comprising approximately 3500 people. Patients had surgery between January 2013 and June 2018, inclusive at Fairfield and Bowral Hospitals.

Following data linkage, analysis was completed on 1185 study participants (64% female, 69% TKA, mean age 67 (9.9)). 30% were using regular opioids pre-operatively. Unadjusted analyses resulted in the following rates in those who were vs were not using opioids pre-operatively (respectively); acute adverse events (39.1% vs 38.6%), acute significant adverse events (5.3% vs 5.7%), late adverse events: (6.9% vs 6.6%), total significant adverse events: (12.5% vs 12.4%), discharge to inpatient rehab (86.4% vs 88.6%), length of hospital stay (5.9 (3.0) vs 5.6 (3.0) days), 6-month post-op Oxford Score (38.8 (8.9) vs 39.5 (7.9)), 6 months post-op EQ-VAS (71.7 (20.2) vs 76.7 (18.2), p<0.001), success post-op described as “much better” (80.2% vs 81.3%).

Adjusted regression analyses controlling for multiple co-variates indicated no significant association between pre-op opioid use and adverse events/patient-reported outcomes.

Pre-operative opioid use was high amongst this Australian arthroplasty cohort and was not associated with increased risk of adverse events post-operatively. Further research is needed in assessing the relationship between the amount of pre-op opioid use and the risk of post-operative adverse events.

Purpose of study

Cauda Equina Syndrome (CES) is a surgical emergency. With Physiotherapists increasingly taking on first-contact and spinal triage roles, screening for CES must be as thorough and effective as possible. This study explores whether Physiotherapists are asking the correct questions, in the correct way and investigates their experiences when screening for this serious condition.

Obesity is associated with worse outcomes following total knee/hip arthroplasty (TKA/TKA). This study aimed to determine the feasibility of a dietitian-led low-inflammatory weight-loss program for people with obesity awaiting arthroplasty.

Quasi-experimental pilot study enrolled people with obesity waitlisted for primary TKA/THA into ‘usual care’ (UC) or weight-loss (low-inflammatory diet) program (Diet). Recruitment occurred between July 2019 and February 2020 at Fairfield and Campbelltown Hospitals. Assessments at baseline, pre-surgery, time of surgery and 90-days following surgery included anthropometric measurements, patient-reported outcomes, serum biomarkers and 90-day postoperative complication rate.

97 people consented to the study (UC, n=47, mean age 67, BMI 37, TKA 79%; Diet, n=50, mean age 66, BMI 36, TKA 72%). Baseline characteristics indicated gross joint impairments and poor compliance with a low-inflammatory diet. Study feasibility criteria included recruitment rate (52%), proportion of diet patients that improved compliance to low-inflammatory diet by ≥10% (57%) and had ≥60% attendance of dietitian consultations (72%), proportion of patients who undertook serum biomarkers (55%).

By presurgery assessments, the diet group had more patients who cancelled their surgery due to symptom improvement (4 vs 0), reduced waist-circumference measurements, increased compliance with the Low-Inflammatory diet and preservation of physical activity parameters. More usual care participants experienced at least one postoperative complication to 90-days (59% vs 47%) and were discharged to inpatient rehabilitation (21% vs 11%). There was no difference in weight change, physical function, and patient-reported outcome measures from pre-surgery to 90-days post-surgery, and length of hospital stay.

Using pre-determined feasibility criteria, conducting a definitive trial is not feasible. However, intervention audit demonstrated high intervention fidelity.

Pilot data suggest our program may promote weight loss but the clinical effects for most are modest. Further research utilising a stronger intervention may be required to assess the effectiveness of a pre-arthroplasty weight-loss intervention.

The external fixator is an invaluable device when treating acute complex trauma and in limb reconstruction. It is therefore important to ensure its efficient and safe application to avoid complications. A lot of research has been done to evaluate the factors around external fixator stability, pin site infections and more is still being done to understand pin loosening. The purpose of this study was to evaluate other factors that may contribute in external fixator pin loosening. The aim was to evaluate if the different Schanz pin insertion techniques contribute to pin loosening.

Two tibia diaphyses from two cadavers were each divided into three sections. Three different drilling techniques were repeated in each of the sections. A total of 36 Schanz pins were inserted and a section cut out of the bone in front of the pins was done allowing visual inspection of the pin hole for features of thread stripping. These features were predefined as thread pattern disruption, smoothening and shallow imprint on the cortex.

Evidence of pin thread stripping was seen in all of the pin insertion techniques. The first method where the hole was pre-drilled and pin inserted with the drill showed 100% thread stripping. The second method of pre-drilling and hand insertion showed the least amount with 16.7% of pin stripping noted and 66.7% pin thread stripping was observed when inserting the pin with power without pre-drilling the pilot hole using the third method.

Different pin insertion techniques result in varying amounts of pin thread stripping. The most amount of thread stripping occurs when a Schanz pin is inserted with power after pre-drilling. This finding, although not measured scientifically, supports the current recommendation of pre-drilling and manual insertion of the pin. In future, more scientific measurement are necessary to quantify these findings and assess their clinical significance.

Elevated blood cobalt secondary to metal-on-metal (MoM) hip arthroplasties has been shown to be a risk factor for developing cardiovascular complications including cardiomyopathy. Published case reports document cardiomyopathy in patients with blood cobalt levels as low as 13µg/l. Clinical studies have found conflicting evidence of cobalt-induced cardiomyopathy in patients with MoM hips. The extent of cardiovascular injury, measured by global longitudinal strain (GLS), in patients with elevated blood cobalt levels has not previously been examined.

Sixteen patients with prospectively collected blood cobalt ion levels above 13µg/l were identified and matched with eight patients awaiting hip arthroplasty with no history of cobalt implants. Patients underwent echocardiogram assessment including GLS.

Patients with MoM hip arthroplasties had a mean blood cobalt level of 29µg/l compared to 0.01µg/l in the control group. There was no difference or correlation in EF, left ventricular (LV) end systolic dimension, LV end diastolic dimension, fractional shortening, ventricular wall thickness or E/e’ ratio. However, GLS was significantly reduced in patients with MoM hip arthroplasties compared to those without (−15.2% v −18%, (MoM v control) p= 0.0125). Pearson correlation demonstrated that GLS is significantly correlated with blood cobalt level (r= 0.8742, p=0.0009).

For the first time, this study has demonstrated reduced cardiac function in the presence of normal EF as assessed by GLS in patients with elevated cobalt above 13µg/l. As GLS is a more sensitive measure of systolic function than EF, routine echocardiogram assessment including GLS should be performed in all patients with MoM hip arthroplasties and elevated blood cobalt.

Abstract