Prosthetic joint infections (PJI) are one of the most devastating complications of joint replacement surgery. They are associated with significant patient morbidity and carry a significant economic cost to treat. The management of PJI varies from antibiotic suppression, debridement, antibiotics, and implant retention (DAIR) procedures through to single/multiple stage revision procedures. Concerns have been raised recently in relation to the rising number of revision arthroplasty procedures that are being undertaken in relation to infection. This database aims to collect data on all PJIs that have been managed in the Australian Capital Territory (ACT) region. This will allow us to investigate the microbial trends, outcomes of surgical intervention and patient outcomes within our local population.

This database will incorporate diagnostic, demographic, microbiological and treatment information in relation to local PJI cases. The data will be collated from the local infectious diseases database, hospital medical records, and where available the Australian Orthopaedic Association National Joint Replacement Registry Data.

The first 100 cases of PJI were assessed. 76% were defined as being acute. 56% of the patients received antibiotics prior to their diagnosis however only 3% were culture negative. 89% were monomicrobial and 11% polymicrobial. The intended management strategy was a DAIR in 38% of patients and a 2-stage revision in 12% of cases. The intended management strategy was successful in 46% of the patients.

The ACT is uniquely placed to analyze and create a local PJI database. This will allow us to guide further treatment and local guidelines in terms of management of these complex patients.

Staphylococcus aureus is the most frequently isolated organism in periprosthetic joint infections. The mechanism by which synovial fluid (SF) kills bacteria has not yet been elucidated, and a better understanding of its antibacterial characteristics is needed. We sought to analyze the antimicrobial properties of exogenous copper in human SF against S. aureus.

SF samples were collected from patients undergoing total elective knee or hip arthroplasty. Different S. aureus strains previously found to be sensitive and resistant, UAMS-1 and USA300 WT, respectively, were used. We performed in-vitro growth and viability assays to determine the capability of S. aureus to survive in SF with the addition of 10µM of copper. We determined the minimum bactericidal concentration of copper (MBC-Cu) and evaluated the sensitivity to killing, comparing WT and CopAZB-deficient USA300 strains.

UAMS-1 evidenced a greater sensitivity to SF when compared to USA300 WT, at 12 (p=0.001) and 24 hours (p=0.027). UAMS-1 significantly died at 24 hours (p=0.017), and USA300 WT survived at 24 hours. UAMS-1 was more susceptible to the addition of copper at 4 (p=0.001), 12 (p=0.005) and 24-hours (p=0.006). We confirmed a high sensitivity to killing with the addition of exogenous copper on both strains at 4 (p=0.011), 12 (p=0.011), and 24 hours (p=0.011). Both WT and CopAZB-deficient USA300 strains significantly died in SF, evidencing a MBC-Cu of 50µM against USA300 WT (p=0.011).

SF has antimicrobial properties against S. aureus, and UAMS-1 was more sensitive than USA300 WT. The addition of 10µM of copper was highly toxic for both strains, confirming its bactericidal effect. We evidenced CopAZB-proteins involvement in copper effluxion by demonstrating the high sensitivity of the mutant strain to lower copper concentrations. Thus, we propose CopAZB-proteins as potential targets and the use of exogenous copper as possible treatment alternatives against S. aureus.

Anterior cruciate ligament (ACL)-retaining total knee arthroplasty (TKA) has been associated with more physiologic motion patterns, more normal knee kinematics, and higher patient preference than ACL-sacrificing implant designs. However, it remains unclear how many osteoarthritic patients can be expected to have an intact ACL at the time of surgery in order to undergo ACL-retaining TKA. A systematic literature review was performed in November 2018 using the PubMed and EMBASE databases. Papers written in English, with more than 10 adult patients relevant to the research question were included, whereas cadaveric, revision, animal and simulation studies and conference abstracts were excluded. Data on ACL retention during intraoperative assessment or MRI scans were extracted and analysed using proportional meta-analyses. Twenty-six eligible publications (4167 knees) were included: 20 using intraoperative assessment, 4 using MRI, and 2 using both. Intraoperative assessment of the ACL during TKA showed that the ligament was present in 78% (95% confidence interval [CI]: 72–84%) and intact in 55% (95% CI: 45–65%) of the patients examined. MRI scans revealed higher percentages of ACL presence and intactness than intraoperative assessment, with 91% (95% CI: 79–96%) of the ACL being present and 68% (95% CI: 28–92%) intact. Fewer studies reported on MRI results compared to studies reporting on the intraoperative status of the ACL. In conclusion, intraoperative assessment suggests that over half of the osteoarthritic patients have an intact ACL at the time of TKA surgery, some of whom may qualify for bicruciate-retaining arthroplasty.

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Introduction

The purpose of this study was to compare pre-operative acetabular cup parameters using this novel dynamic imaging sequence to the Lewinnek safe zone

Techniques for fixation of the lateral malleolus have remained essentially unchanged since the 1960s, but are associated with complication rates of up to 30%. The fibular nail is an alternative method of fixation requiring a minimal incision and tissue dissection, and has the potential to reduce complications.

We reviewed the results of 105 patients with unstable fractures of the ankle that were fixed between 2002 and 2010 using the Acumed fibular nail. The mean age of the patients was 64.8 years (22 to 95), and 80 (76%) had significant systemic medical comorbidities.

Various different configurations of locking screw were assessed over the study period as experience was gained with the device. Nailing without the use of locking screws gave satisfactory stability in only 66% of cases (4 of 6). Initial locking screw constructs rendered between 91% (10 of 11) and 96% (23 of 24) of ankles stable. Overall, seven patients had loss of fixation of the fracture and there were five post-operative wound infections related to the distal fibula. This lead to the development of the current technique with a screw across the syndesmosis in addition to a distal locking screw. In 21 patients treated with this technique there have been no significant complications and only one superficial wound infection. Good fracture reduction was achieved in all of these patients. The mean physical component Short-Form 12, Olerud and Molander score, and AAOS Foot and Ankle outcome scores at a mean of six years post-injury were 46 (28 to 61), 65 (35 to 100) and 83 (52 to 99), respectively. There have been no cases of fibular nonunion.

Nailing of the fibula using our current technique gives good radiological and functional outcomes with minimal complications, and should be considered in the management of patients with an unstable ankle fracture.

Six week old male Sprague-Dawley rats were administered intravenous clozapine, quetiapine, haloperidol or vehicle once daily for a period of 42 days with access to only high fat diet and their weight was monitored regularly. At the end of the study the rats were killed and the tibiae excised and bone mineral density (BMD) measured with dual X-ray absorptiometry and bone architecture assessed with micro-computed tomography (micro-CT) and associated software. Results were subjected to one-way ANOVA and post hoc Dunnetts multiple comparison test.

All treatment groups were compared to control. There were no significant differences in body weight between the different groups at completion of the study. Clozapine treated animals alone showed a significant reduction in bone mineral density (p<0.05) however no differences were seen with haloperidol and quetiapine. Both haloperidol and quetiapine, but not clozapine, treatment showed a significant reduction in the bone to tissue volume ratio (BV/TV) by approximately 23% (p<0.05) and an increase in trabecular number (TbN) by approximately 21% (p<0.05). Trabecular bone architecture parameters for haloperidol and quetiapine, but not clozapine, showed more rod like and disconnected structure as reflected in the increases in structure model index (SMI) of around 15% (p<0.05) and trabecular pattern factor (TbPf) by 22% (p<0.05).

This data demonstrates that in rats receiving a high fat diet, haloperidol and quetiapine have an adverse effect on bone micro-architecture without significant change in whole body bone mineral density.

Clozapine did not affect bony architecture in a significant manner as reported in our earlier study, though bone mineral density was reduced. Reasons for the different effect of clozapine in this study are still uncertain but may be related to the significant weight loss seen at the end point of the previous study. Causes for osteoporosis and increased fracture risk in schizophrenia may include smoking history, malnutrition, limited sun exposure and compliance.

Long term administration of both typical and atypical anti-psychotics may have a negative effect on bone and is a further factor that can influence this risk. An awareness of this relationship is useful in the orthopaedic management of schizophrenic patients.

TKA (Total Knee Arthroplasty) is a successful operation. Soft tissue problems with TKA are difficult to treat. Flap surgery is successful in treating this problem and salvaging the prostheses. We present results of flap surgery for complicated TKAs over a ten year period, performed by a single surgeon.

Between 1996 and 2005, 31 patients (32 knees) underwent flap surgeries for TKAs. Four of these procedures were done prophylactically in patients with previous knee surgeries. Gastrocnemius, medial fasciocutaneous and anterior compartment flaps were used either solely or in combination based on the size of the defect. The data was collected retrospectively from case-notes and correspondence from the treating orthopaedic surgeons. All the knees included in the study had a minimum follow up of 6 months.

The patients were aged between 50 and 94 years. Indication for primary TKA was osteoarthritis in 26 patients and rheumatoid arthritis in 5. The index orthopaedic surgery was a primary knee arthroplasty in 14 and revision in 13. The average duration between the TKA and flap surgery was 11 weeks (range 1 – 52). Gastrocnemius was the most commonly used local flap (17 cases). Anterior compartment flap was used in 5 cases and in the rest combination of flaps was used. Coagulase -ve Staph. aureus was the most commonly isolated organism from the perioperative wound swabs. Successful soft tissue cover was achieved in 29 of 32 knees (92%). Overall, TKA was salvaged in 23 of 32 knees (72%) and 3 knees (9.7%) underwent arthrodesis. Three (9.7%) patients had above knee amputation, two of these had post op MRSA infection. We could not use a functional knee scoring system due to inadequate information available.

We conclude local flap surgery is a viable and successful procedure for providing soft tissue cover for complicated TKAs with good results.

Shoulder pain represents a significant burden of disease in the general population, yet there is a lack of evidence about the effectiveness of routinely used interventions. Current management of ‘painful arc’ of the shoulder in Primary Care is not evidence-based.

Over a six-month period patients with ‘painful arc’ of less than six months duration were recruited via their GPs. Eligible patients were consented to enter the trial and were then randomised, by sealed envelopes, to one of four arms of the study: control (normal analgesia and/or non-steroidal anti-inflammatory medication), a specified and repeatable Exercise and Manual Therapy Package (EMTP), a course of up to three subacromial steroid injections or both the EMTP and the steroid injections. The interventions and clinic follow-ups were over an 18-week period. A final postal questionnaire was sent out at one year. The progress of the patients was monitored using the Oxford Shoulder Score (OSS) and the SF36 general health questionnaire.

Seventy-nine GPs referred 186 patients, of whom 112 were randomised (Control=27, EMTP=29, Injections=28, Both=28). 64 patients were female and 48 male. The mean age was 54.5 years (range 23-88 years). Ninety patients completed the trial (Control=20, EMTP=22, Injections=26, Both=22). Sixty-two returned the follow-up questionnaire.

By paired sample t-tests, no significant differences were found between the OSS scores or SF-36 (physical health total) at the beginning and end of the intervention period, or at one year, in any group. There were no differences in changes in scores between groups. Two patients in the injection group went on to surgery, along with one each in the control and EMTP groups.

We have found no significant differences in outcome between steroid injections, a physiotherapy package, both treatments, or symptomatic treatment in our group of patients presenting with symptoms of painful arc of the shoulder.

Patients with spinal cord injuries have been seen to have increased healing of attendant fractures. This for the main has been a clinical observation with laboratory work confined to rats. While the benefits in relation to quicker fracture healing are obvious, this excessive bone growth (heterotopic ossification) also causes unwanted side effects, such as decreased movement around joints, joint fusion and renal tract calculi. However, the cause for this phenomenon remains unclear.

This paper evaluates two groups with spinal column fractures – those with neurological compromise (n=10) and those without (n=15), and compares them with a control group with isolated long bone fractures (n=12). Serum was taken from these patients at five specific time intervals post injury (1 day, 5 days, 10 days, 42 days (6 weeks) and 84 days (12 weeks)). These samples were then analysed for levels of Transforming Growth Factor-Beta (TGF-β using the ELISA technique. This cytokine has been shown to stimulate bone formation after both topical and systemic administration.

Results show TGF-β levels of 142.79+/-29.51 ng/ml in the neurology group at 84 days post injury. This is higher than any of the other time points within this group (p=0.009 vs. all other time points, ANOVA). Furthermore, this level is also higher than the levels recorded in the no neurology (103.51+/-36.81 ng/ml) and long bone (102.28=/-47.58 ng/ml) groups at 84 days post-injury (p=0.009 and p=0.04 respectively, ANOVA).

In conclusion, the results of this work, carried out for the first time in humans, offers strong evidence of the causative role of TGF-β in the increased bone turnover and attendant complications seen in patients with acute spinal cord injuries.