Epidemiology and estimated economic impact of musculoskeletal injuries in polytrauma patients in a level one trauma centre in Singapore.

Introduction: Musculoskeletal injuries are the most common reason for surgical intervention in polytrauma patients. Methods: This is a retrospective cohort study of 560 polytrauma patients (injury severity score [ISS] >17) who suffered musculoskeletal injuries (ISS >2) from 2011 to 2015 in National University Hospital, Singapore. Results: 560 patients (444 [79.3%] male and 116 [20.7%] female) were identified. The mean age was 44 (range 3-90) years, with 45.4% aged 21-40 years. 39.3% of the patients were foreign migrant workers. Motorcyclists were involved in 63% of road traffic accidents. The mean length of hospital stay was 18.8 (range 0-273) days and the mean duration of intensive care unit (ICU) stay was 5.7 (range 0-253) days. Patient mortality rate was 19.8%. A Glasgow Coma Scale (GCS) score <12 and need for blood transfusion were predictive of patient mortality (p < 0.05); lower limb injuries, road traffic accidents, GCS score <8 and need for transfusion were predictive of extended hospital stay (p < 0.05); and reduced GCS score, need for blood transfusion and upper limb musculoskeletal injuries were predictive of extended ICU stay. Inpatient costs were significantly higher for foreign workers and greatly exceeded the minimum insurance coverage currently required. Conclusion: Musculoskeletal injuries in polytrauma remain a significant cause of morbidity and mortality, and occur predominantly in economically productive male patients injured in road traffic accidents and falls from height. Increasing insurance coverage for foreign workers in high-risk jobs should be evaluated.

Frailty, length of stay and cost in hip fracture patients.

A hip fracture causes high morbidity and mortality. Frailty is associated with adverse outcomes and increased costs. Frailty measured using the Hospital Frailty Risk Score (HFRS) is associated with higher costs and adverse outcomes. HFRS is useful as a fuss-free frailty measurement in the management of older adults with hip fractures. INTRODUCTION: Hip fractures account for an increasing number of hospital admissions around the world and are associated with high rates of morbidity and mortality. Frailty is increasingly recognized to be associated with adverse outcomes and increased costs. The purpose of this study is to determine the association of the Hospital Frailty Risk Score (HFRS) with the healthcare cost and outcomes in older adults who present with a hip fracture. METHODS: A retrospective analysis was performed on 1014 patients ≥ 60 years who presented with a hip fracture between January 2016 to June 2020. Each patient was classified into HFRS low, intermediate or high frailty cohorts. Demographics, hip fracture type, comorbidities, Charlson Comorbidity Index (CCI), American Society of Anesthesiologist score (ASA), costs, length of stay, time to surgery, complications, readmission rate and mortality were compared between the cohorts. RESULTS: Median total hospitalization costs were significantly higher in the highest HFRS (SGD$22,432) patients as compared to intermediate (SGD$18,759) and low HFRS (SGD$15,671) patients. The difference between the high and low groups remains significant after adjusting for covariates using quantile regression. Similar results were shown for median length of stay (14 vs 10 vs 8 days), total number of complications (2 vs 1 vs 0) and adjusted time to surgery (p < 0.05). HFRS was not associated with 30-day readmission or 30-day or 1-year mortality. CONCLUSION: Frailty is associated with a marked increase in total costs in hip fracture patients. HFRS proved useful in estimating LOS and outcomes for older patients with hip fractures.

Surgery for chronic arthropathy in people with haemophilia.

BACKGROUND: Chronic arthropathy is a potentially debilitating complication for people with haemophilia - a genetic, X-linked, recessive bleeding disorder, characterised by the absence or deficiency of a clotting factor protein. Staging classifications, such as the Arnold-Hilgartner classification for haemophilic arthropathy of the knee, radiologically reflect the extent of knee joint destruction with underlying chronic synovitis. Management of this highly morbid disease process involves intensive prophylactic measures, and chemical or radioisotope synovectomy in its early stages. However, failure of non-surgical therapy in people with progression of chronic arthropathy often prompts surgical management, including synovectomy, joint debridement, arthrodesis, and arthroplasty, depending on the type of joint and extent of the damage. To date, management of people with mild to moderate chronic arthropathy from haemophilia remains controversial; there is no agreed standard treatment. Thus, the benefits and disadvantages of non-surgical and surgical management of mild to moderate chronic arthropathy in people with haemophilia needs to be systematically reviewed.  OBJECTIVES: To assess the efficacy and safety of surgery for mild to moderate chronic arthropathy in people with haemophilia A or B. SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Coagulopathies Trials Register, CENTRAL, MEDLINE, Embase, CINAHL, and two trial registers to August 2022. We also handsearched relevant journals and conference abstract books. SELECTION CRITERIA: Randomized controlled trials (RCTs) and quasi-RCTs comparing surgery and non-surgical interventions, for any joint with chronic arthropathy, in people with haemophilia, who were at least 12 years old. DATA COLLECTION AND ANALYSIS: The review authors did not identify any trials to include in this review. MAIN RESULTS: The review authors did not identify any trials to include in this review. AUTHORS' CONCLUSIONS: The review authors did not identify any trials to include in this review. Due to a lack of research in this particular area, we plan to update the literature search every two years, and will update review if any new evidence is reported. There is a need for a well-designed RCT that assesses the safety and efficacy of surgical versus non-surgical interventions for chronic arthropathy in people with haemophilia.

3D printing in fracture treatment : Current practice and best practice consensus.

The use of 3D printing in orthopedic trauma is supported by clinical evidence. Existing computed tomography (CT) data are exploited for better stereotactic identification of morphological features of the fracture and enhanced surgical planning. Due to complex logistic, technical and resource constraints, deployment of 3D printing is not straightforward from the hospital management perspective. As a result not all trauma surgeons are able to confidently integrate 3D printing into the daily practice. We carried out an expert panel survey on six trauma units which utilized 3D printing routinely. The most frequent indications are acetabular and articular fractures and malalignments. Infrastructure and manpower structure varied between units. The installation of industrial grade machines and dedicated software as well as the use of trained personnel can enhance the capacity and reliability of fracture treatment. Setting up interdisciplinary jointly used 3d printing departments with sound financial and management structures may improve sustainability. The sometimes substantial logistic and technical barriers which impede the rapid delivery of 3D printed models are discussed.

[3D printing in fracture treatment : Current practice and best practice consensus]. / 3D-Druck in der Frakturversorgung : Aktuelle Praxis und "Best-practice"-Konsens.

The use of 3D printing in orthopedic trauma is supported by clinical evidence. Existing computed tomography (CT) data are exploited for better stereotactic identification of morphological features of the fracture and enhanced surgical planning. Due to complex logistic, technical and resource constraints, deployment of 3D printing is not straightforward from the hospital management perspective. As a result not all trauma surgeons are able to confidently integrate 3D printing into the daily practice. We carried out an expert panel survey on six trauma units which utilized 3D printing routinely. The most frequent indications are acetabular and articular fractures and malalignments. Infrastructure and manpower structure varied between units. The installation of industrial grade machines and dedicated software as well as the use of trained personnel can enhance the capacity and reliability of fracture treatment. Setting up interdisciplinary jointly used 3d printing departments with sound financial and management structures may improve sustainability. The sometimes substantial logistic and technical barriers which impede the rapid delivery of 3D printed models are discussed.

Epidemiology of pelvic and acetabular fractures in a tertiary hospital in Singapore.

Introduction: Pelvic and acetabular fractures (PAFs) usually result from high-energy, potentially life-threatening accidents. They are one of the major injuries that lead to death in patients involved in such accidents. We studied the recent epidemiology of these injuries in Singapore. Methods: This is a retrospective data analysis of all trauma patients who underwent surgery for PAFs from 2008 to 2016 in a tertiary trauma centre in Singapore. Data including patient demographics, mechanism of injury and associated injuries was collected. Results: A total of 169 patients were admitted for PAFs over the eight-year period. The majority (79.3%) were male. The mean age was 41 (range 13-79) years. Most patients (51.5%) were Chinese. The most common mechanisms of injury were road traffic accidents (53.8%), falls (33.1%) and crush injuries (13.0%). 46.2% sustained acetabular fractures, while 44.4% sustained pelvic fractures. PAFs were most commonly associated with upper and lower limb injuries, followed by spinal and thoracic injuries. Average of length of stay in hospital was 24 (range 2-375) days. Conclusion: PAF predominantly affects young working males. Compared to previously published local data, there has been a significant reduction in the incidence of PAFs, likely due to improved road and work safety. The demographics of PAFs have changed, with fewer injuries in females (20.7% vs. 33.3%), a reduction in the proportion of injuries in the Chinese (51.5% vs. 70.1%). While road traffic accidents remain the most common cause, crush injuries are now more prevalent (13.0%).

Standard versus customised locking plates for fixation of schatzker ii tibial plateau fractures.

AIM: 3D-printed implants could improve the capture of fracture fragments for improved stability of tibial plateau fracture fixation. The aim of this study was to compare the biomechanical strength of fixation constructs using standard and customised 3D-printed proximal tibial locking plates for fixation of tibial plateau fractures. METHODS: This is a biomechanical study utilising six pairs of cadaveric tibiae. Fractures were created in an identical fashion using an osteotome and mallet, and fixed using either a standard, commercially-available proximal tibia locking plate or a customised 3D-printed plate. Design and production of the customised plates followed a "3D printing at point-of-care" model. Customised stainless steel 316 L plates were produced within a local additive manufacturing laboratory based upon pre-operative CT scans. Determination of implant choice within each cadaver pair was performed via simple randomisation. Following fracture fixation, the tibiae were skeletalised and biomechanically tested using a customised loading jig and a size-matched femoral knee prosthesis. The constructs were loaded cyclically from 100 N to approximately three times the cadaveric body-weight at 5 Hz for 10 000 cycles. Every 1000 cycles, the test was paused and the tibia was physically checked for failure. If failure had not occurred by the end of the testing cycle, the construct was loaded to failure and the load at which the construct failed was noted. RESULTS: Fixation constructs using the 3D-printed plates performed comparably to those using the standard plates. There was no significant difference in the degree of fracture fragment displacement in both constructs. Overall longitudinal construct stiffness and load to failure was higher in the 3D-plates group but this did not reach statistical significance. CONCLUSION: Production of customised plates for proximal tibia fractures at point-of-care is feasible, however fixation constructs with these plates did not provide any biomechanical advantage over standard plates in terms of axial loading stiffness.

Post-Processing and Surface Characterization of Additively Manufactured Stainless Steel 316L Lattice: Implications for BioMedical Use.

Additive manufacturing of stainless steel is becoming increasingly accessible, allowing for the customisation of structure and surface characteristics; there is little guidance for the post-processing of these metals. We carried out this study to ascertain the effects of various combinations of post-processing methods on the surface of an additively manufactured stainless steel 316L lattice. We also characterized the nature of residual surface particles found after these processes via energy-dispersive X-ray spectroscopy. Finally, we measured the surface roughness of the post-processing lattices via digital microscopy. The native lattices had a predictably high surface roughness from partially molten particles. Sandblasting effectively removed this but damaged the surface, introducing a peel-off layer, as well as leaving surface residue from the glass beads used. The addition of either abrasive polishing or electropolishing removed the peel-off layer but introduced other surface deficiencies making it more susceptible to corrosion. Finally, when electropolishing was performed after the above processes, there was a significant reduction in residual surface particles. The constitution of the particulate debris as well as the lattice surface roughness following each post-processing method varied, with potential implications for clinical use. The work provides a good base for future development of post-processing methods for additively manufactured stainless steel.

Point-of-Care 3D Printing: A Feasibility Study of Using 3D Printing for Orthopaedic Trauma.

AIM: The aim of this study was to assess the feasibility of 3D printing a customised implant at the point of care from a manufacturing and logistics perspective. We hypothesised that customised plate production would be possible within a clinically relevant time frame of 72 hours using currently available technology. MATERIALS AND METHODS: This study uses 6 cadaveric lower limbs to simulate real-life surgical patients. Split-depressed lateral tibial plateau fractures were created in an identical fashion in the cadaveric lower limbs. CT scans of the fractures were obtained and digital reconstructions were used to design customised patient and fracture-specific 3D-printed plates. These were subsequently printed in medical grade stainless steel 316L and post-processed at a local additive manufacturing centre. Surgical fixation of the fractures was then carried out using these plates, following which post-operative X-rays were obtained. The time taken for each step in plate production from the initiation of pre-operative CT scan to the completion of the post-operative X-ray was recorded. RESULTS: Six customised proximal tibia locking plates were produced with accompanying surgical drill guides. The mean total time taken for plate fabrication from completion of CT scan was approximately 24 hours and 7 minutes, with a maximum of 28 hours and 46 minutes. CONCLUSION: Production of patient-specific 3D printed plates for fixation of proximal tibia fractures at the point of care is achievable within a clinically acceptable time frame provided adequate manufacturing facilities and skilled manpower are in place.

Computer-Navigated versus Conventional Total Knee Arthroplasty: A Meta-Analysis of Functional Outcomes from Level I and II Randomized Controlled Trials.

The main purpose of this article is to provide an up-to-date systematic review and meta-analysis comparing functional outcomes of total knee arthroplasty using either computer navigation (NAV-TKA) or conventional methods (CON-TKA) from the latest assemblage of evidence. This study was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-Analysis of Observational Studies in Epidemiology guidelines. All Level I and II randomized controlled trials (RCTs) in PubMed, EMBASE, and Cochrane that compared functional outcomes after NAV- and CON-TKA were included in the review. Selected end points for random effects, pairwise meta-analysis included Knee Society Knee Score (KSKS), KS Function Score (KSFS), KS Total Score (KSTS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and range of motion at three arbitrary follow-up times. A total of 24 prospective RCTs comprising 3,778 knees were included from the initial search. At long-term follow-up (>5 years), NAV-TKA exhibited significantly better raw KSKS (p = 0.001) (low-quality evidence), contrary to CON-TKA, which reflected significantly better raw KSTS (p = 0.004) (high-quality evidence). While change scores (KSKS, WOMAC) from preoperative values favor CON-TKA at short-term (<6 months) and medium-term follow-up (6-60 months), long-term follow-up change scores in KSKS suggest the superiority of NAV-TKA over CON-TKA (p = 0.02) (very low-quality evidence). Overall, sizeable dispersion of nonstatistically significant functional outcomes in the medium term was observed to eventually converge in the long term, with less differences in functional outcome scores between the two treatment methods in short- and long-term follow-up. While raw functional outcome scores reflect no differences between NAV and CON-TKA, long-term follow-up change scores in KSKS suggest superiority of NAV-TKA over its conventional counterpart. Prospective studies with larger power are required to support the pattern of diminishing differences in functional outcome scores from medium- to long-term follow-up between the two modalities.

Robot-Assisted versus Conventional Total and Unicompartmental Knee Arthroplasty: A Meta-analysis of Radiological and Functional Outcomes.

The study aims to provide an up-to-date systematic review and meta-analysis comparing radiological and functional outcomes of total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA) using either robotic assistance or conventional methods from the latest assemblage of evidence. This study was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and MOOSE (Meta-analysis of Observational Studies in Epidemiology) guidelines. All studies in PubMed, EMBASE, Medline, and Cochrane that reported radiological and functional outcomes after TKA or UKA with either robotic or conventional methods were included in the review. Selected endpoints for random effects, pairwise meta-analysis included operative details, radiological outcomes (mechanical axis, component angle deviation, and outliers), and functional outcomes (American Knee Society Score, Knee Society Function Score, revision and complication rate, range of motion (ROM), Hospital for Special Surgery score, and Western Ontario and McMaster Universities Osteoarthritis Index). A total of 23 studies comprising 2,765 knees were included from the initial search. Robot-assisted TKA and UKA were associated with significantly better component angle alignment accuracy (low-to-high quality evidence) at the cost of significantly greater operation time. Robot-assisted UKA was found to have significantly better short-term functional outcomes compared with conventional UKA (moderate-to-high quality evidence). Robot-assisted TKA, however, did not exhibit significantly better short- and midterm subjective knee outcome scores compared with its conventional counterpart (high-quality evidence). Robot-assisted TKA and UKA were associated with nonstatistically significant improved ROM and lesser rates of revision. Robot-assisted total and unicompartmental knee arthroplasty leads to better radiological outcomes, with no significant differences in mid- and long-term functional outcomes compared with conventional methods for the former. Larger prospective studies with mid- and long-term outcomes are required to further substantiate findings from the present study.

Definitive Surgery Is Safe in Borderline Patients Who Respond to Resuscitation.

OBJECTIVES: We hypothesize that in adequately resuscitated borderline polytrauma patients with long bone fractures (femur and tibia) or pelvic fractures, early (within 4 days) definitive stabilization (EDS) can be performed without an increase in postoperative ventilation and postoperative complications. DESIGN: Retrospective cohort study. SETTING: Level 1 trauma center. PATIENTS: In total, 103 patients were included in this study; of whom, 18 (17.5%) were female and 85 (82.5%) were male. These patients were borderline trauma patients who had the following parameters before definitive surgery, normal coagulation profile, lactate of <2.5 mmol/L, pH of ≥7.25, and base excess of ≥5.5. INTERVENTION: These patients were treated according to Early Total Care, definitive surgery on day of admission, or Damage Control Orthopaedics principles, temporizing external fixation followed by definitive surgery at a later date. Timing of definitive surgical fixation was recorded as EDS or late definitive surgical fixation (>4 days). MAIN OUTCOME MEASURES: Primary outcome measured was the duration of ventilation more than 3 days post definitive surgery and presence of postoperative complications. RESULTS: Thirty-five patients (34.0%) received Early Total Care, whereas 68 (66.0%) patients were treated with Damage Control Orthopaedics. In total, 51 (49.5%) of all patients had late definitive surgery, whereas 52 patients (50.5%) had EDS. On logistic regression, the following factors were found to be predictive of higher rates of postoperative ventilation ≥ 3 days, units of blood transfused, and time to definitive surgery > 4 days. Increased age, head abbreviated injury score of 3 or more and time to definitive surgery were found to be associated with an increased risk of postoperative complications. CONCLUSIONS: Borderline polytrauma patients with no severe soft tissue injuries, such as chest or head injuries, may be treated with EDS if adequately resuscitated with no increase in need for postoperative ventilation and complications. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Finite element analysis of bone and implant stresses for customized 3D-printed orthopaedic implants in fracture fixation.

3D printing allows product customisation to be cost efficient. This presents opportunity for innovation. This study investigated the effects of two modifications to the locking compression plate (LCP), an established orthopaedic implant used for fracture fixation. The first was to fill unused screw holes over the fracture site. The second was to reduce the Young's modulus by changing the microarchitecture of the LCP. Both are easily customisable with 3D printing. Finite element (FE) models of a fractured human tibia fixed with 4.5/5.0 mm LCPs were created. FE simulations were conducted to examine stress distribution within the LCPs. Next, a material sweep was performed to examine the effects of lowering the Young's modulus of the LCPs. Results showed at a knee joint loading of 3× body weight, peak stress was lowered in the modified broad LCP at 390.0 MPa compared to 565.1 MPa in the original LCP. It also showed that the Young's modulus of material could be lowered to 50 GPa before the minimum principal stresses increased exponentially. These findings suggested the modifications could lead to improved performances of fracture fixation, and therefore likely that other orthopaedic implants survivorship could also be enhanced by customisation via 3D printing. Graphical abstract.

A comparison of Streptococcus agalactiae septic arthritis and non-Streptococcus agalactiae septic arthritis.

INTRODUCTION: Streptococcus agalactiae (Group B Streptococcus, GBS) is an uncommon cause of septic arthritis in the adult population. In recent years, there has been an increase in the incidence of GBS septic arthritis. This study aims to compare the clinical presentation, investigations, microbiology and outcome of management in patients with GBS and non-GBS septic arthritis. METHODS: Retrospective review of hospital surgical records was done to identify all patients treated surgically at our institution from January 2011 to January 2016 for primary septic arthritis. Patients were categorised into two groups: those with culture-proven GBS septic arthritis and those with causative pathogens that were not GBS. Patients who were medically unfit for surgical intervention as well as those who declined interventional procedures were excluded from the study. RESULTS: A total of 83 patients were included in the study: 62 (74.7%) had non-GBS septic arthritis and 21 (25.3%) had GBS septic arthritis. Patients with GBS septic arthritis were more likely to have polyarticular involvement (p < 0.001) and involvement of less common sites such as the elbow joint. They were also more likely to have elevated inflammatory markers (C-reactive protein > 150 mg/L; p = 0.017) and positive blood cultures (p = 0.02), and were typically healthy adults with no medical comorbidities (p = 0.012). CONCLUSION: Patients with GBS septic arthritis were more likely to present with polyarticular involvement, positive blood cultures and higher levels of C-reactive protein on admission, and tended to be healthier individuals with no medical comorbidities.

Accuracy of sacroiliac screw placement with and without intraoperative navigation and clinical application of the sacral dysmorphism score.

INTRODUCTION: Percutaneously-placed sacroiliac (SI) screws are currently the gold-standard fixation technique for fixation of the posterior pelvic ring. The relatively high prevalence of sacral dysmorphism in the general population introduces a high risk of cortical breach with resultant neurovascular damage. This study was performed to compare the accuracy of SI screw placement with and without the use of intraoperative navigation, as well as to externally validate the sacral dysmorphism score in a trauma patient cohort. PATIENTS AND METHODS: All trauma patients who underwent sacroiliac screw fixation for pelvic fractures at a level 1 trauma centre over a 6 year period were identified. True axial and coronal sacral reconstructions were obtained from their pre-operative CT scans and assessed qualitatively and quantitatively for sacral dysmorphism - a sacral dysmorphism score was calculated by two independent assessors. Post-operative CT scans were then analysed for breaches and correlated with the hospital medical records to check for any clinical sequelae. RESULTS: 68 screws were inserted in 36 patients, most sustaining injuries from road traffic accidents (50%) or falls from height (36.1%). There was a male preponderance (83.3%) with the majority of the screws inserted percutaneously (86.1%). Intraoperative navigation was used in 47.2% of the patient cohort. 30.6% of the cohort were found to have dysmorphic sacra. The mean sacral dysmorphism scores were not significantly different between navigated and non-navigated groups. Three cortical breaches occurred, two in patients with sacral dysmorphism scores >70 and occurring despite the use of intraoperative navigation. There was no significant difference in the rates of breach between navigated and non-navigated groups. None of the breaches resulted in any clinically observable neurovascular deficit. CONCLUSION: The sacral dysmorphism score can be clinically applied to a cohort of trauma patients with pelvic fractures. In patients with highly dysmorphic sacra, reflected by high sacral dysmorphism scores, intraoperative navigation is not in itself sufficient to prevent cortical breaches. In such patients it would be prudent to consider instrumentation of the lower sacral corridors instead.

Unstable Open Posterior Subtalar Dislocation Treated With a Ring External Fixator: A Case Report and Review of the Literature.

Traumatic dislocation of the subtalar joint is an infrequently occurring injury, with open true posterior dislocation an even rarer injury. We describe our treatment of a young motorcyclist who was brought into hospital after a road traffic accident, having sustained an open posterior subtalar dislocation. After initial reduction and resuscitation in the emergency department, he was taken to the operating theater for emergent wound debridement and external fixation of his ankle using a unilateral external fixator device. After 2 subsequent repeat debridements, this was changed to a ring external fixator device, followed by split-thickness skin grafting of his wound. He was allowed full weightbearing and was discharged from hospital 10 days after his last operation. He continued to improve clinically at his outpatient appointments to the 1-year follow-up point, with his external fixator removed at 6 weeks postoperatively. At the last follow-up appointment, he had successfully returned to his previous employment. To the best of our knowledge, only 1 other description of an open posterior dislocation has been reported, which was managed nonoperatively after wound debridement. Ours is the first reported case of an open posterior dislocation managed surgically using a ring external fixator. We believe the ability to allow immediate weightbearing resulting from the additional stability provided by this type of fixation is advantageous, with a theoretical reduction in the risk of periarticular osteoporosis and calf muscle atrophy. The early mobilization afforded by this treatment is hoped to improve the typically poor long-term outcomes for these patients.

Actinobacillus hominis osteomyelitis: First reported case in the English language medical literature.

INTRODUCTION: Actinobacillus hominis is currently a rarely reported pathogen. It has previously been associated with respiratory tract infections and bacteraemia in debilitated patients. However, under-reporting may occur due to misidentification by commonly used laboratory bacterial identification systems. This case is, to the best of our knowledge, the first reported case of A. hominis osteomyelitis in the English language medical literature. CASE PRESENTATION: A 37-year-old male presented with a painful foot. He had no previous foot problems, history of injury or animal contact. Osteomyelitis was confirmed by magnetic resonance imaging (MRI), and blood cultures were positive for Gram-variable bacilli. The organism was identified initially as Pasteurella pneumotropica by the local routine diagnostic laboratory and as a Pasteurella species by the UK National Reference Laboratory (Colindale, London, UK), using standard operating procedures at the time. It was finally identified as an A. hominis using 16S rRNA gene sequence analysis. Difficulties in the accurate identification of this organism remain current, as other biochemical identification systems have also resulted in misidentifications. The patient refused admission and intravenous antibiotics. He was successfully treated using an 8-week course of oral ciprofloxacin and amoxicillin based on antibiotic disc susceptibility testing resulting in clinical, serological and radiological resolution. CONCLUSION: Laboratories should maintain a high index of suspicion for A. hominis as several commonly used bacterial identification systems may not accurately identify the organism. Colonial morphology and absence of animal contact should prompt consideration of this organism in appropriate clinical situations. Oral ciprofloxacin and amoxicillin treatment was successful in this case.

Bisphosphonate-induced periprosthetic fracture: a cause of painful total hip arthroplasty.

Background. Cases have been reported in the literature of periprosthetic fractures associated with the use of bisphosphonates occurring in the long term following a Total Hip Replacement (THR). We report an interesting case of periprosthetic fracture secondary to bisphosphonate use only a few months after a THR. Case Report. A 72-year-old lady (on bisphosphonates for 10 years) underwent a THR for osteoarthritis. She was pain-free in the first four months postoperatively. Thereafter, she developed spontaneous onset of pain in the lateral aspect of her thigh and groin and found it difficult to weight-bear. X-rays and blood tests were unremarkable. An ultrasound and MRI scan showed no evidence of effusion/collection or periprosthetic fracture. A radionuclide bone scan showed an abnormal appearance of the right femoral shaft. A subsequent CT scan showed an oblique vertical split on the anterior surface of the upper right femoral shaft. This stress fracture was managed nonoperatively with protected weight bearing. She has progressed well with good clinical and radiological signs of fracture healing. Conclusion. This case is an important addition to our knowledge that bisphosphonate-induced periprosthetic stress fractures can be a cause of hip pain only a few months following a THR.

Fracture of an Exeter 'cement in cement' revision stem: a case report.

The 'cement in cement' technique for revision hip arthroplasty has become popular in recent years, particularly in relation to polished taper stems. Since 2006 a short Exeter stem with 44 mm offset has been available specifically for this purpose. We report a fracture of such a stem in the absence of trauma 5 years after the revision procedure. The patient had a BMI of 27.8 and the proximal cement mantle gave good support to the stem. The fracture initiated and propagated from the introducer hole on the shoulder of the prosthesis. Macroscopically there was no defect in this area. This may be an unusual case of fatigue failure.