Aims

To assess the feasibility of a randomized controlled trial (RCT) that compares three treatments for acetabular fractures in older patients: surgical fixation, surgical fixation and hip arthroplasty (fix-and-replace), and non-surgical treatment.

Displaced acetabular fractures in the older patient present significant treatment challenges. There is evidence the morbidity and mortality associated is similar to the fractured neck of femur cohort. Despite growing literature, there remains significant controversy regarding treatment algorithms; varying between conservative management, to fracture fixation and finally surgical fixation and simultaneous THA to allow immediate full weight bearing.

£250k NIHR, Research for Patient Benefit (Ref: PB-PG-0815-20054). Trial ethical approval (17/EE/0271). After national consultation, 3 arms included; conservative management, fracture fixation and simultaneous fracture fixation with THA. Statistical analysis required minimum 12 patients/3 arms to show feasibility, with an optimum 20/arm. Inclusion criteria; patients >60 years & displaced acetabular fracture. Exclusion criteria: open fracture, THA in situ, pre-injury immobility, polytrauma. Primary outcome measure - ability recruit & EQ-5D-5L at 6 months. Secondary outcome measures (9 months); OHS, Disability Rating Index, radiographs, perioperative physiological variables including surgery duration, blood loss, complications and health economics.

11 UK level 1 major trauma centres enrolled into the trial, commenced December 2017. Failure surgical equipoise was identified as an issue regarding recruitment. Full trial recruitment (60 patients) achieved; 333 patients screened. 66% male, median age 76 (range 63–93), median BMI 25 (range 18–37), 87% full mental capacity, 77% admitted from own home. 75% fall from standing height. 60% fractures; anterior column posterior hemi-transverse. Trial feasibility confirmed December 2020. Presented data- secondary outcomes that are statistically significant in improvement from baseline for only the fix and replace arm, with acceptable trial complications. Issues are highlighted with conservative management in this patient cohort.

Our unique RCT informs design and sample size calculation for a future RCT. It represents the first opportunity to understand the intricacies of these treatment modalities. This RCT provides clinicians with information on how best to provide management for this medically complex patient cohort.

Despite the high prevalence of musculoskeletal disorders seen by primary care physicians, numerous studies have demonstrated deficiencies in the adequacy of musculoskeletal education at multiple stages of medical education. The aim of this study was to assess a newly developed undergraduate module in musculoskeletal medicine.

Introduction

Acetabular fractures are a challenging problem. It has been published that outcome is dependent upon the type of fracture, the reduction of the fracture and concomitant injuries. The end-points of poor outcome include avascular necrosis of the femoral head, osteoarthritis. However, we lack definitive statistics and so counselling patients on prognosis could be improved. In order to achieve this, more outcome studies from tertiary referral centres are required. We present the first long term follow up from a large tertiary referral centre in Ireland.

Introduction

Acetabular fractures are a challenging problem. It has been published that outcome is dependent upon the type of fracture, the reduction of the fracture and concomitant injuries. The end-points of poor outcome include avascular necrosis of the femoral head, osteoarthritis. However, we lack definitive statistics and so counselling patients on prognosis could be improved. In order to achieve this, more outcome studies from tertiary referral centres are required. We present the first long term follow up from a large tertiary referral Centre in Ireland.

Study Objective: To determine the feasibility of ultrasound-guided femoral nerve blockade performed by orthopaedic trainees.

Methods: This was a prospective study involving patients presenting to Acciedent & Emergency with fractured femurs requiring analgesia. Physicians performing the nerve blocks were orthopaedic trainees who had participated in a 1-hour training session. The participants underwent ultrasonography-guided femoral nerve blocks to provide analgesia. Any additional analgesia required was recorded. Subjects rated their pain on a Numerical Pain Rating Scale (NRS) before the nerve block and 30 & 60minutes after the nerve block. The primary outcomes for feasibility were the requirement for additional analgesia following injection and the median reduction in pain on the Numerical Pain Rating Scale after the nerve block. Secondary outcomes for feasibility included the median time for completion of the entire nerve block procedure for each subject (from initiation of ultrasonography to completion of the last injection) and the percentage of participants wishing to have the same procedure for similar injuries in the future. Other secondary outcomes included the percentage of participants with complications during the procedure including nerve and vascular injection.

Results: All procedures (100%) were completed without additional anesthesia or analgesia with significant reduction in Numerical Pain Rating Scale. There were no immediate complications

Conclusion: Orthopaedic trainees can perform ultrasound-guided femoral nerve blocks in the emergency department with high patient satisfaction, after minimal training.

Introduction: Despite a resurgence in cobalt-chromium metal-on-metal arthroplasty and hip resurfacing, the potential toxicity of cobalt ions in the periprosthetic area remains a cause for concern. Cytotoxic effects have been demonstrated in macrophages with cobalt ions inducing apoptosis and TNF-α secretion. A similar cytotoxic effect has been demonstrated in osteoblast-like cells. However, these studies assessed the acute cellular response to cobalt ions over 48 hours. To date, the effect on osteoblasts of chronic exposure to cobalt ions is unknown.

Aim: In this study we investigated the effect on osteoblasts of chronic exposure to cobalt ions. Specifically we investigated the chemokine response and effect on osteoblast function. We also investigated for a change in osteoblast phenotype to a less differentiated mesenchymal cell type.

Methods. Primary human osteoblasts were cultured and treated with cobalt (10ppm) over 21 days. Secreted chemokines (IL-8, MCP-1, TNF-α) were assayed using enzyme-linked immunosorbent assays (ELISA). Osteoblast function was assessed via alkaline phosphatase activity and calcium deposition. For a change in osteoblast phenotype, osteoblast gene expression was assessed using real time PCR. Immunoflourescent cell staining of actin filaments was used to examine for a change in osteoblast morphology.

Results: Chemokine (IL-8) secretion by osteoblasts was significantly increased after 7 days of stimulation with cobalt ions. In parallel with this, osteoblast function was also significantly inhibited as demonstrated by reduced alkaline phosphatase activity and calcium deposition. Regarding osteoblast phenotype, FSP-1, CTGF and TGF-β gene expression were upregulated after 7 days exposure indicating a transition in osteoblast phenotype to a less differentiated mesenchymal cell type. Immunoflourescent staining of actin filaments also showed a change in osteoblast morphology. Taken together, these data demonstrate cobalt ions induce a change in the osteoblast phenotype to that of a mesenchymal cell type. This is the first study to investigate osteoblast plasticity in the context of periprosthetic osteolysis.

Conclusion: After prolonged exposure to cobalt ions, IL-8 chemokine secretion is increased which attracts neutrophils to the periprosthetic area. Furthermore, osteoblasts no longer function as osteogenic cells as demonstrated by a decrease in osteoblast alkaline phosphatase activity and calcium deposition. Instead, they undergo transition to a mesenchymal cell type as demonstrated by an increase in the expression of genes associated with a mesenchymal cell lineage. Instead of secreting osteoid matrix the new cell type secretes unmineralized collagen. Cobalt ions are not benign and may play an important role in periprosthetic osteolysis by inducing osteoblasts to undergo transition to a less differentiated mesenchymal cell type.

Introduction: Despite a resurgence in cobalt-chromium metal-on-metal arthroplasty, the potential toxicity of metal ions in the periprosthetic area remains a cause for concern. Studies to date have assessed the acute effect of cobalt ions on osteoblasts over 48 hours. The aim of our study was to determine the response of osteoblasts to cobalt ions over a prolonged period of exposure.

Methods. Primary human osteoblasts were cultured and treated with cobalt (10ppm) over 21 days. Osteoblast function was assessed via alkaline phosphatase activity and calcium deposition. ELISA were used to assess chemokine (IL-8, MCP-1 and TNF-α) secretion. Osteoblast gene expression was assessed using microarray analysis and real time PCR. Immunoflourescent cell staining of actin filaments was used to examine osteoblast morphology.

Results: Chemokine (IL-8) secretion by osteoblasts was significantly increased after 10 days of stimulation with cobalt ions. In parallel with this, osteoblast function was also significantly inhibited as demonstrated by reduced alkaline phosphatase activity and calcium deposition. Regarding osteoblast phenotype, FSP-1, CTGF and TGF-β gene expression were upregulated indicating a transition in osteoblast phenotype. Immunoflourescent staining of actin filaments also showed a change in osteoblast morphology. Taken together, these data show cobalt ions induce a change in the osteoblast phenotype to that of a mesenchymal cell type.

Conclusion: After 10 days of treatment with cobalt ions, osteoblasts no longer function as osteogenic cells. they undergo transition to a mesenchymal cell type. Furthermore, IL-8 secretion is increased which attracts neutrophils to the periprosthetic area thereby contributing to the inflammatory response that characterises osteolysis.

Horse riding is a popular competitive sport and leisure pursuit worldwide. Previous research has highlighted the unpredictable and independent nature of horses and high injury risk inherent in travelling at speeds of up to 65kph, 3-metres above the ground on an animal weighing between 450–500kg. In Ireland, jockeys register with the Turf Club as either professional or amateur with the remaining riders participating as unregistered.

The aim of this study is to determine the national incidence of acute spinal cord injury (ASCI) and vertebral body injury (VBI) in horse riding in the Republic of Ireland, and to compare and contrast injury characteristics in registered and unregistered riders over an 11-year period (1995–2005).

Chart review and structured telephone interview was performed in all cases to determine mechanism of injury, discipline, protective equipment, immediate management and whether the rider considered the injury could be prevented. American Spinal Injuries Association (ASIA) impairment score was used to classify outcome. Data for injuries sustained in competitive racing, for both registered and unregistered riders, was correlated with Irish Turf Club race records to ensure accuracy.

Results: Sixteen cases of ASCI and 46 of VBI were identified over the study period (Table 1). Over the study period, there was a mean annual incidence of 1.5 (1 to 4) ASCI and 4 VBI (0 to 7). Cervical injuries were significantly more likely to result in ASCI (n=14 (52%), p=0.004) than either thoracic or lumbar injuries. Riders who had an ASCI spent more days in hospital (p=0.007); were less likely to have had a previous riding injury (p= 0.046); and following injury, less likely to return to horse riding at any level (p= 0.033). Seven ASCI (44%) and ten VBI (22%) patients were managed operatively. Three ASCI (19%) and 4 VBI (9%) occurred in registered riders. A fall in flight jumping was the commonest injury pattern (32%) overall, with 60% of ASCI and 26% of VBI by this mechanism occurring in registered riders. Overall, only 19% of riders report wearing a back protector at the time of injury. Of these, 30% sustained cervical injury, 17% thoracic injury and 0% lumbar injury. For ASCI riders, final ASIA impairment classification was A= 4, B= 2, D= 4 and E= 5.

Conclusion: Equestrian sports, both for registered and unregistered riders pose substantial risk. Despite greater compliance with wearing of protective equipment, registered riders are at increased risk of sustaining ASCI than unregistered risers. Morbidity is significant following ASCI, with ten riders permanently disabled as a direct result of participation.