Hip resurfacing may be a useful surgical procedure when patient selection is correct and only implants with superior performance are used. In order to establish a body of evidence in relation to hip resurfacing, pseudotumour formation and its genetic predisposition, we performed a case-control study investigating the role of HLA genotype in the development of pseudotumour around MoM hip resurfacings. All metal-on-metal (MoM) hip resurfacings performed in the history of the institution were assessed. A total of 392 hip resurfacings were performed by 12 surgeons between February 1st 2005 and October 31st 2007. In all cases, pseudotumour was confirmed in the preoperative setting on Metal Artefact Reduction Sequencing (MARS) MRI. Controls were matched by implant (ASR or BHR) and absence of pseudotumour was confirmed on MRI. Blood samples from all cases and controls underwent genetic analysis using Next Generation Sequencing (NGS) assessing for the following alleles of 11 HLA loci (A, B, C, DRB1, DRB3/4/5, DQA1, DQB1, DPB1, DPA1). Statistical significance was determined using a Fisher's exact test or Chi-Squared test given the small sample size to quantify the clinical association between HLA genotype and the need for revision surgery due to pseudotumour. Both groups were matched for implant type (55% ASR, 45% BHR in both the case and control groups). According to the ALVAL histological classification described by Kurmis et al., the majority of cases (63%, n=10) were found to have group 2 histological findings. Four cases (25%) had group 3 histological findings and 2 (12%) patients had group 4 findings. Of the 11 HLA loci analysed, 2 were significantly associated with a higher risk of pseudotumour formation (DQB1*05:03:01 and DRB1*14:54:01) and 4 were noted to be protective against pseudotumour formation (DQA1*03:01:01, DRB1*04:04:01, C*01:02:01, B*27:05:02). These findings further develop the knowledge base around specific HLA genotypes and their role in the development of pseudotumour formation in MoM hip resurfacing. Specifically, the two alleles at higher risk of pseudotumour formation (DQB1*05:03:01 and DRB1*14:54:01) in MoM hip resurfacing should be noted, particularly as patient-specific genotype-dependent surgical treatments continue to develop in the future.
Europe has found itself at the epicentre of the COVID-19 pandemic. Naturally, this has placed added strain onto healthcare systems internationally. It was feared that the impact of the COVID-19 pandemic could overrun the Irish healthcare system. As such, the Irish government opted to introduce a national lockdown on the 27 March 2020 in an attempt to stem the flow of admissions to hospitals. Similar lockdowns in the UK and New Zealand have resulted in reduced emergency department presentations and trauma admissions. The aim of this study is to assess the effect of the national lockdown on trauma presentations to a model-3 hospital in Dublin, Ireland. A retrospective study was conducted. All emergency department presentations between 27 March 2019 to 27 April 2020 and 27 March 2020 to 27 April 2020 were cross-referenced against the National Integrated Medical Imaging System-Picture Archiving Communication System (NIMIS-PACS) radiology system to identify those with radiologically proven skeletal trauma. These patients were grouped according to sex, age, discharge outcome, mechanism of injury, and injury location.Aims
Methods
The emergence of a new variant of subtrochanteric stress fractures of the femur affecting patients on oral bisphosphonate therapy has only recently been described. This fracture is often preceded by pain and distinctive radiographic changes, and associated with a characteristic fracture pattern. We undertook a review of this cohort of patients in our service. A retrospective review was carried out looking for patients with subtrochanteric fractures who were taking oral bisphosphonates presenting with a low velocity injury over a two year period. Clinical data and radiographs were assessed.Introduction
Method
Hip fractures pose a significant burden on the healthcare system. Hyperglycaemia and a state of Type 2 diabetes exists post operatively. Being normoglycaemic has well documented benefits. Pre operative carbohydrate loading has been shown to have two good effects. It decrease hyperglycaemia post operatively and allows the patient to undergo less strict fasting protocols. Insulin resistance to date has not been examined in these patients and this was determined using a validated formula (HOMA/IR). Three trauma hospitals were enrolled and patients with hip fractures requiring operative fixation were enlisted. Exclusion criteria: diabetic patients and inability to imbibe. 100 neck of femur fractures were examined. 46 patients were fasted normally. 32 test patients were given a carbohydrate rich drink pre operatively the night before surgery and in the morning up to 2 hours prior to surgery. 22 patients were excluded. Serum random glucose and insulin levels were taken on admission. Fasting serum glucose and insulin levels were taken on day one post operatively.Aims
Methods
The two most common complications of femoral impaction bone grafting are femoral fracture and massive implant subsidence. We investigated fracture forces and implant subsidence rates in embalmed human femurs undergoing impaction grafting. The study consisted of two arms, the first examining the force at which femoral fracture occurs in the embalmed human femur, and the second examining whether significant graft implant/subsidence occurs following impaction at a set force at two different impaction frequencies. Using a standardized impaction grafting technique with modifications, an initial group of 17 femurs underwent complete destructive impaction testing, allowing sequentially increased, controlled impaction forces to be applied until femoral fracture occurred. A second group of 8 femurs underwent impaction bone grafting at constant force, at an impaction frequency of 1 Hz or 10 Hz. An Exeter stem was cemented into the neomedullary canals. These constructs underwent subsidence testing simulating the first 2 months of postoperative weight bearing.Background and purpose
Methods
Conservative management remains the gold standard for many fractures of the humeral diaphysis with union rates of over 90% often quoted. Success with closed management however is not universal. A retrospective review of all conservatively managed fractures between 2001 and 2005 was undertaken to investigate a suspected high non-union rate and identify possible causes. The overall non-union rate was 39.2% (11 of 28 cases). There was no difference in axial distraction at presentation, however following application of cast there was significantly more distraction in the non-union group (1.2 v 5.09mm, p<0.01). All humeral fractures were admitted, lightweight U-slabs were applied by a technician, distraction was avoided, patients abstained from NSAIDS, consultant reviewed radiographs before discharge and patients were converted early to functional brace.Phase 1
Changes to practise
A comprehensive met-analysis of anterior knee pain post intramedullary nailing of the tibia was performed by Katsoulis et al in 2006. The principle findings were that 47.4% of patients had anterior knee pain at 2 years post tibial nailing. Worse results were found following a patella tendon splitting approach when compared with a medial para-patellar tendon approach. These conclusions were drawn from 20 studies including 1460 patients. Currently both approaches to the proximal tibia for nailing are used at JCMH Blanchardstown. A retrospective study was performed to compare the results of tendon splitting and tendon sparing approaches to tibial nails and to compare the results of JCMH with those stated in literature. Patients who underwent tibial nailing in 2007 and 2008 were identified using the hospital coding system. Those patients who were treated under the care of Mr Kenny had a medial para-tendinous approach and those treated the care of Mr O'Flanagan and Mr Keogh had a tendon splitting approach. Apart from the approach the nailing technique using the Trigen Knee Nail and the post operative physiotherapy protocol were identical. Follow up included questions regarding knee pain and return to previous function. Specifically: Knee pain that affects daily life, Knee pain on kneeling, Knee pain on ascending or descending stairs, Return to work and Return to sports or active hobbies.Introduction
Method
Surgical experience has been shown to improve the clinical outcomes in Total hip arthroplasty. The objective of this study was to compare clinical and radiological outcomes between Consultants and NCHDs grade surgeons for the Exeter total hip replacement taken from the Cappagh National Orthopaedic Hospital Joint Register. Between 2005 and 2008, 2749 primary total hip replacements were done, 433(15.78%) were Exeter total hip system. 380(86%) out of 433 were included in the study, 227(59%) were females and 154(41%) were males. A consultant was the primary surgeon for 193(51%) patients and an NCHD was the primary surgeon for 187(49%) patients. Mean age, at time of operation was 68 years. Clinical outcome was assessed with WOMAC and SF36 scoring system. Patients were invited to fill in the WOMAC and SF36 questionnaire, pre-operatively, at 6 months and at 2 years after the operation. Radiographs were evaluated for radiolucency with a standardized technique.Introduction
Methods & Materials
The incidence of osteochondral lesions following ankle fractures varies in the literature between 17-70%. They are commonly associated with chronic pain and swelling in patients diagnosed with such pathology. There is less evidence about the relationship between OCL and the development of post-traumatic osteoarthritis, the most common type of ankle arthritis. Through the use of MRI 8 weeks following ankle fractures, we investigated the incidence of OCL in patients treated both surgically and conservatively for ankle fractures of all AO subtypes.Introduction
Methods
A laboratory based study investigating fracture forces and implant subsidence rates in embalmed human femurs undergoing impaction grafting. Human femurs were harvested from cadavers for destructive impaction testing. An initial group of femurs underwent destructive impaction testing, using the impaction grafting technique as described by Gie et al, modified, allowing increasing, controlled impaction forces to be applied until femoral fracture occurred. A second group of embalmed human femurs underwent impaction bone grafting at constant force, with varied impaction frequencies. An Exeter stem was cemented into the neo-medullary canals. These constructs underwent subsidence testing simulating the first 2 months post-operative weight-bearing.Summary
Methods
The process of femoral impaction grafting requires vigorous impaction to obtain adequate stability but the force of impaction has not been determined. This process has been reported to result in femoral fractures with rates reaching 16%. The aims of this study were to determine the threshold force required for femoral impaction grafting, to determine the affect cortical thickness, canal diameter and bone mineral density (BMD) have on this threshold force and to measure subsidence of an Exeter prosthesis following impaction at the threshold force. Adult sow femurs were prepared and placed through a DEXA scanner and the BMD and canal diameter measured. Thirty five femurs were impacted with morsellised bone chips and an increasing force of 0.5kN was applied until the femur fractured. Using callipers the cortical thickness of the bone was measured along the fracture line. Once the threshold force was determined 5 femurs were impacted to this threshold force and an Exeter stem was cemented into the neomedullary canal and a 28mm Exeter head attached. Axial cyclic loading was performed between 440N (swing phase of gait) and 1320N (stance phase of gait) for 150,000 cycles at a frequency of 3Hz. The position sensor of the hydraulic testing machine measured the subsidence. 29 tests were successfully completed. The threshold force was found to be 4kN. There was no significant correlation between the load at fracture and the cortex: canal ratio or the bone mineral density. Following impaction with the maximum force of 4kN the average subsidence for the 5 femurs was 0.276mm (range 0.235 – 0.325mm). In this animal study the threshold force was 4kN. Minimal axial subsidence of the implant occurred when impacting the graft with this threshold force. We therefore achieved a stable construct without fracture which is the ultimate goal for the revision hip surgeon.
