Acetabular Fractures in older patients Intervention Trial (AceFIT): a feasibility triple-arm randomized controlled study.

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. Methods: Patients were recruited from seven UK NHS centres and randomized to a three-arm pilot trial if aged older than 60 years and had a displaced acetabular fracture. Feasibility outcomes included patients' willingness to participate, clinicians' capability to recruit, and dropout rates. The primary clinical outcome measure was the EuroQol five-dimension questionnaire (EQ-5D) at six months. Secondary outcomes were Oxford Hip Score, Disability Rating Index, blood loss, and radiological and mobility assessments. Results: Between December 2017 and December 2019, 60 patients were recruited (median age 77.4 years, range 63.3 to 88.5) (39/21 M/F ratio). At final nine-month follow-up, 4/60 (7%) had withdrawn, 4/60 (7%) had died, and one had been lost to follow-up; a 98% response rate (50/51) was achieved for the EQ-5D questionnaire. Four deaths were recorded during the three-year trial period: three in the non-surgical treatment group and one in the fix-and-replace group. Conclusion: This study has shown a full-scale RCT to be feasible, but will need international recruitment. The Acetabular Fractures in older patients Intervention Trial (AceFIT) has informed the design of a multinational RCT sample size of 1,474 or 1,974 patients for a minimal clinically important difference of 0.06 on EQ-5D, with a power of 0.8 or 0.9, and loss to follow-up of 20%. This observed patient cohort comprises a medically complex group requiring multidisciplinary care; surgeon, anaesthetist, and ortho-geriatrician input is needed to optimize recovery and rehabilitation.

The floating hip injury: a descriptive study and case-control analysis.

PURPOSE: A "floating hip" (FH) injury is a rare injury describing the simultaneous ipsilateral fracture of the femur and pelvis or acetabulum (P/A). We describe our experience with patients presenting with FH injuries and compare them to controls with similar P/A fractures but without femoral involvement. METHODS: Medical records and radiographs of FH patients and controls presenting to our tertiary centre between 2015 and 2020 were reviewed. Follow-up data from outpatient clinical records were also extracted. The control group were extensively matched by age, sex, body mass index, fracture classification and energy of injury. RESULTS: From 1392 recorded P/A fractures, 42 FH cases were identified (average age 39 years, 78.6% males). The most common femoral fracture was the midshaft (35.7%), followed by the neck of femur (26.2%). 90.5% of FH injuries were due to high-energy mechanisms. 64.3% of P/A fractures, and 100% of femoral fractures were managed surgically. Compared to controls, FH cases were more likely to have additional orthopaedic injuries (73.8% vs. 40.5%, p = 0.002), more total theatre admissions (mean 2.5 vs. 1.19, p < 0.001), longer hospital stays (28.3 vs. 14.9 days, p = 0.02), and a higher rates of post-op complications (53.8% vs. 20%, p = 0.025). CONCLUSIONS: We report differences in the presentation, management, and outcomes of FH injuries versus controls, even after extensive matching for confounders. These differences may inform future treatment strategies for the FH injury.

The clinical characteristics and management of paediatric pelvic fractures: a changing landscape based on skeletal maturity.

INTRODUCTION: Paediatric pelvic fractures (PPFs) are uncommon but signify serious trauma. A comprehensive multidisciplinary approach is needed due to a high number of associated injuries. This study aims to retrospectively analyse PPFs over a 5-year period and evaluate how advancing skeletal maturity changes fracture patterns and management plans. METHODS: The trauma database was retrospectively reviewed for pelvic fractures in patients aged ≤ 18 years. Radiographs and CT scans were used to classify pelvic injuries according to the modified Torode classification and determine the status of the triradiate cartilage (open: skeletally immature; closed: skeletally mature). Data collected also included the mechanism of injury, clinical and functional outcomes, and associated injuries. Logistic regression analysis was performed to identify risk factors for associated abdominal injuries. RESULTS: 65 PPFs (2.8% of paediatric trauma admissions during the study period) were classified as type I (3.1%), type II (7.7%), type IIIa (32.3%), type IIIb (38.5%), type IV (18.5%) according to the modified Torode classification. The mean age was 13.41 ± 3.82. Skeletally immature children were more likely to be hit by a motor vehicle as a pedestrian (p < 0.001), be intubated (p = 0.009), acquire Torode type II (p = 0.047) and rami fractures (p = 0.037), and receive chest (p = 0.005) and head injuries (p = 0.046). Skeletally immature children were also less likely to acquire Torode type IV fractures (p = 0.018), receive surgical treatment for their pelvic injuries (p = 0.036), and had a faster time to full weight bearing (p = 0.013). Pelvis AIS score ≥ 4 (OR 5.3; 95% CI 1.3-22.6; p = 0.023) and a pedestrian accident (OR 4.9; 95% CI 1.2-20.7; p = 0.030) were risk factors for associated abdominal injuries. There was a strong association between a higher pelvic fracture grade and the proportion of patients with closed triradiate cartilage (p = 0.036), hospital length of stay (p = 0.034), mean pelvic AIS score (p = 0.039), a pelvis AIS score of ≥ 4 (p = 0.022), mean ISS (p = 0.003), an ISS score between 25 and 75 (p = 0.004), average time to FWB (p = 0.001), requirement of blood products (p = 0.015), and a motor vehicle accident (p = 0.037). CONCLUSION: PPFs occurring in skeletally mature and immature patients are significantly different in terms of mechanism of injury, fracture severity, fracture pattern, and management strategy. There is a high rate of associated injuries, necessitating an integrated multidisciplinary approach in paediatric trauma centres.

Fix and replace: Simultaneous fracture fixation and hip replacement for acetabular fractures in older patients.

INTRODUCTION: Displaced acetabular fractures in the elderly present significant treatment challenges. The 'fix and replace' concept involves open reduction and internal fixation of the acetabulum, providing bony stability to accept the press-fit of an acetabular cup, with a cemented femoral stem. This allows early mobilisation and the advantages this confers. This study of 57 patients treated with fix and replace describes our technique, outcomes, and survival analysis. METHODS: A retrospective review of 57 'fix and replace' procedures in patients aged over 60 was performed. Data was collected on mechanism, fracture type, demographics, time to surgery, comorbidity index, complications, EQ-5D and Oxford hip scores (OHS). Radiographs were reviewed for fracture healing, implant loosening, cup migration, and heterotopic ossification. RESULTS: 57 patients aged 60 to 95 had fix and replace surgery. The median ASA score was 3. The mean Charlson Index was 4.8. 45 patients had a low-energy fall, 6 had a road traffic accident, 3 fell off a bicycle, and 1 mechanism was unclear. The fracture patterns were anterior column posterior hemitransverse (67%), associated both columns (9%), posterior column (9%), posterior column and posterior wall (9%), and transverse (2%). The mean time to surgery was 8.4 days (0-14). 26 out of 57 (46%) received a blood transfusion. Mean length of stay was 17.6 days (7-86). The mean follow-up was 35.5 months. 4 dislocations were treated with closed reduction, whilst 1 required excision arthroplasty. 2 infections resolved with debridement, antibiotics, and implant retention (DAIR), whilst 1 required a two-stage revision. 1 acetabular component had migrated requiring revision. The median pre-injury OHS was 44 (26-48) compared to 37.3 (28-48) at 1 year. There were no deaths at 30-days, whilst at 1 year 7 patients had died. Kaplan Meier survival analysis showed mean survival was 1984.5 days. Implant survival was 90% at 1 year. CONCLUSION: While fix and replace is conceptually attractive, this medically complex patient group requires considerable support peri­ and post-operatively. Further studies are required to provide clinicians with more information to decide on how best to provide a holistic management strategy for such injuries in this frail patient cohort.

Cycling-related trauma admissions to the major trauma centre in the cycling capital of the United Kingdom.

PURPOSE: This study aims to characterise cycling related injuries presenting to a major trauma centre located within a region with the highest rates of cycling in the UK. METHODS: A retrospective analysis of cycling related trauma admissions occurring between January 2012 and June 2020 was performed. Our institution's electronic patient record system was used to collect relevant data for analysis including age, gender, mechanism of injury, Glasgow coma scale (GCS) on arrival, incident date and time, injured body regions, 30-day mortality, helmet use and intubation rate. Comparison was made between groups of patients based on mechanism of injury. RESULTS: A total of 605 cycling related trauma cases were identified, with 52 being excluded due to incomplete data. The most common mechanism was 'fall from cycle' (53.5%). The 'cyclist v vehicle' group was associated with a significantly higher Injury Severity score (ISS), lower GCS and higher intubation rate. Helmet wearers were significantly older than non-wearers and helmet use was associated with a significantly reduced risk of head injury, lower ISS and intubation rate and a higher GCS. DISCUSSION: With a likely increase in future cycling uptake, it is crucial that effective interventions are implemented to improve the safety of cyclists. The findings of this study may be used to guide any such intervention. A multi-faceted strategy involving driver and cyclist education, effective road infrastructure changes and helmet promotion campaigns specifically targeting the younger generation could be employed.

The Harrington plus reconstruction for pelvic and acetabular metastases.

BACKGROUND: Surgical management of periacetabular bone metastases is challenging. The Harrington Plus reconstruction is a modification of the original Harrington rod technique. An intrapelvic suprapectineal plate is used, with the aim of reconstructing a disrupted anterior column and reducing the risk of failure in cases where there is extensive medial bone loss. METHODS: A retrospective review of the 13 patients who have undergone the Harrington Plus procedure to date was performed. Mobility status, EQ5D and Oxford Hip scores were assessed. RESULTS: There was a significant improvement in mobility status, EQ5D and Oxford Hip Scores at 6 months postoperatively (p < 0.05). Two patients returned to theatre for debridement of infection. There were no postoperative dislocations, cup medialisation or cases of loosening of the prosthesis. No patient required revision arthroplasty surgery. CONCLUSION: The Harrington Plus procedure produces a reliable construct that allows patients with extensive periacetabular metastatic defects to fully weight-bear. Careful patient selection and multidisciplinary management is essential.

Factors associated with mortality in older patients sustaining pelvic or acetabular fractures.

INTRODUCTION: This study aimed to investigate potential factors, including delay to surgical stabilisation, affecting mortality in older patients sustaining pelvic or acetabular (PA) fractures. MATERIALS AND METHODS: A retrospective review of the Trauma Audit and Research Network (TARN) database was performed to identify older patients (aged 65 and over) sustaining PA fractures treated surgically in a UK Major Trauma Centre (MTC) between 2015 and 2019. Chi-squared and Fisher tests were used to compare 1-year mortality rates following operative intervention between patients treated within 72 h and after 72 h. Kaplan-Meier curves were used to visualise survival probability; significant predictors of survival were found using Cox proportional hazard models. RESULTS: Of 564 older patients with PA fractures, 70 met the inclusion criteria. The mean age was 76.1 years. The overall 1-year mortality rate was 20%. When patients were grouped by time to surgery (fracture fixation within or greater than 72 h), there was no statistically significant difference in 1-year mortality. Patients whose surgery was delayed more than 72 h were more likely to have longer hospital stays (p = 0.002) or to have suffered from polytrauma (p = 0.025). Age, Charlson Co-morbidities Index (CCI) and pre-op mobility status were associated with statistically significant differences in overall mortality. The same factors were associated with a significantly increased hazard of death in the multivariate Cox proportional hazards model. Patient gender, mechanism of injury, Injury Severity Score (ISS) > 15 and head injury were not significant predictors of mortality. CONCLUSION: Surgical intervention within 72 h of injury did not result in decreased mortality in older patients with PA fractures. The 1-year mortality rate between older PA fractures and hip fractures was comparable. Consideration should be given to a combined multidisciplinary approach between orthogeriatric and expert PA surgeons for these patients.

Trauma epidemiology after easing of lockdown restrictions: experience from a level-one major trauma centre in England.

PURPOSE: The COVID-19 pandemic transformed the delivery of trauma care. We examined the effect of lockdown easing on trauma presentation and management from one Major Trauma Centre (MTC). METHODS: Data was retrospectively analysed from Trauma Audit and Research Network (TARN) on patients presenting to our MTC with trauma. The first 47 days of lockdown (23rd March-9th May 2020, period 1) were compared with the next 47 (10th May-26th June 2020, period 2) and last (27th June-13th August 2020, period 3). Data collected included demographics, mechanism and severity of injury, management and length of stay. RESULTS: 1249 patients were included; 62.2% were male with a mean age of 57.73. Footfall declined in April 2020 compared with 2019 (56 vs. 143) but rebounded by May (123 vs. 120 patients). Road traffic collisions increased over periods one-three (18.8% vs. 23% vs. 30.1%, p = 0.038); deliberate self-harm (DSH) increased in period two compared with one and three (6.3% vs. 3.4% vs. 1.4%, p = 0.03), respectively. When compared with 2019, the 2020 patient age was lower, with less trauma relating to alcohol (7.3% vs. 13.2%, p = 0.009), but more from DSH (3.6% vs. 2.1%, p = 0.10). In 2020 less patients were assessed by a consultant and trauma team, with a shorter stay in hospital and critical care. CONCLUSION: This is the first study to document trauma trends through a lockdown and thereafter. After lockdown easing, trauma footfall rapidly rebounded to 2019 levels. This should be acknowledged in resource allocation decisions if future lockdowns are necessitated.

Sequential low molecular weight heparin and rivaroxaban for venous thromboprophylaxis in pelvic and acetabular trauma.

INTRODUCTION: Patients with pelvic trauma are at high risk of thromboembolic complications, but effective methods of prophylaxis are still to be accepted widely. The incidence of venous thromboembolism (VTE) has been reported to be as high as 61%, which represents the commonest cause of morbidity and mortality in this cohort. New oral anticoagulants are now available and may be used instead of LMWH injections for extended prophylaxis. Rivaroxaban has not been comprehensively considered in the previous pelvic and acetabular trauma literature, but its known benefits include increased patient compliance, especially in the minority of patients who are unable to self-administer injections, and that it does not require monitoring. MATERIALS AND METHODS: All patients referred to our pelvic trauma service between 2015 and 2020 were considered for this study, exclusion criteria involved those patients who had contraindications to rivaroxaban, those who were referred to our service but were never managed at our centre and those managed by other teams (e.g. neurosurgery). Operative patients were initially managed with LMWH until 24 h post-operatively when they started rivaroxaban. Conservatively managed patients started Rivaroxaban straight away. Data were collected on demographics, injury mechanism, fracture classification and clinically relevant VTE and bleeding events up until 3 months post discharge. RESULTS: The overall incidence of VTE was 2%. These represented 3 DVTs and 3 PEs, and occurred in patients who were managed operatively. No major bleeding events were observed. There were two minor bleeding events, both occurring in patients who were managed conservatively with rivaroxaban alone, and they did not require further intervention. 90% of patients surveyed expressed preference for oral prophylaxis. Reported compliance with rivaroxaban was 100%. CONCLUSION: Our data show that this VTE regimen protocol is safe and effective in this group of injured patients and is at least non-inferior to the standard prophylaxis of LMWH alone.

Pushing the Surgical Limits: Primary Total Knee Arthroplasty Using Rotational Prosthesis in a 96-Year-Old Lady with End-Stage Osteoarthritis.

We present the case of a 96-year-old patient treated for severe osteoarthritis with primary total knee arthroplasty (TKA) using a rotational prosthesis. The patient had significant medical comorbidities and her independence was limited due to her severe functional immobility. This case demonstrates that TKA can be a safe procedure with good outcomes in nonagenarians with severe osteoarthritis. Thorough discussion of treatment options is crucial for elderly patients with multiple medical comorbidities. TKA in the nonagenarian population can restore function and independence for patients which may reduce the burden on social care.

Dynamic hip screw fixation of subtrochanteric femoral fractures.

INTRODUCTION: A subtrochanteric proximal femur fracture occurs in the 5 cm of bone immediately distal to the lesser trochanter. UK national guidelines advise that adults with subtrochanteric fractures should be treated with an intramedullary nail (IMN). This study aims to compare peri-operative outcome measures of patients with subtrochanteric fractures treated with either an IMN or a dynamic hip screw (DHS) construct. MATERIALS AND METHODS: We retrospectively reviewed subtrochanteric fractures presenting at our institution over 4.5 years (October 2014-May 2019), classifying them into two treatment groups; IMN and DHS. These groups were compared on outcome measures including surgical time, blood loss, radiation dose area product (DAP), length of stay, re-operation rate and mortality. RESULTS: During the time period studied, 86 patients presented with a subtrochanteric fracture of the femur; with 74 patients (86%) receiving an IMN and 12 (14%) receiving a DHS. The comparative outcome measures reaching statistical significance were blood loss and radiation DAP. The DHS group showed a significantly lower mean blood loss of 776 ml compared to 1029 ml in the IMN group. Also, the DHS group showed a significantly lower mean DAP of 150.30 mGy cm2 compared to 288.86 mGy cm2 in the IMN group. CONCLUSION: Although UK national guidelines recommend treating all subtrochanteric fractures with an IMN; the outcome measures assessed in our study did not show use of an IMN to be superior to a DHS. The DHS group showed a lower estimated blood loss and a reduced DAP. This, along with the reduced financial cost associated with a DHS, may support the use of DHS over IMN for certain subtrochanteric fractures of the femur. There may not be a single favourable implant for the treatment of subtrochanteric fractures as a whole; instead different subtypes of fracture may be amenable to a number of fixation devices. Choice of implant should be determined locally and based on existing and future clinical and health economic research.

Knee Fix or Replace Trial (KFORT): a randomized controlled feasibility study.

AIMS: The aim of this study was to assess the feasibility of conducting a full-scale, appropriately powered, randomized controlled trial (RCT) comparing internal fracture fixation and distal femoral replacement (DFR) for distal femoral fractures in older patients. PATIENTS AND METHODS: Seven centres recruited patients into the study. Patients were eligible if they were greater than 65 years of age with a distal femoral fracture, and if the surgeon felt that they were suitable for either form of treatment. Outcome measures included the patients' willingness to participate, clinicians' willingness to recruit, rates of loss to follow-up, the ability to capture data, estimates of standard deviation to inform the sample size calculation, and the main determinants of cost. The primary clinical outcome measure was the EuroQol five-dimensional index (EQ-5D) at six months following injury. RESULTS: Of 36 patients who met the inclusion criteria, five declined to participate and eight were not recruited, leaving 23 patients to be randomized. One patient withdrew before surgery. Of the remaining patients, five (23%) withdrew during the follow-up period and six (26%) died. A 100% response rate was achieved for the EQ-5D at each follow-up point, excluding one missing datapoint at baseline. In the DFR group, the mean cost of the implant outweighed the mean cost of many other items, including theatre time, length of stay, and readmissions. For a powered RCT, a total sample size of 1400 would be required with 234 centres recruiting over three years. At six months, the EQ-5D utility index was lower in the DFR group. CONCLUSION: This study found that running a full-scale trial in this country would not be feasible. However, it may be feasible to undertake an international multicentre trial, and our findings provide some guidance about the power of such a study, the numbers required, and some challenges that should be anticipated and addressed. Cite this article: Bone Joint J 2019;101-B:1408-1415.

Pulmonary embolism following complex trauma: UK MTC observational study.

OBJECTIVES: To describe the incidence of pulmonary embolism (PE) in a critically ill UK major trauma centre (MTC) patient cohort. METHODS: A retrospective, multidataset descriptive study of all trauma patients requiring admission to level 2 or 3 care in the East of England MTC from 1 November 2014 to 1 May 2017. Data describing demographics, the nature and extent of injuries, process of care, timing of PE prophylaxis, tranexamic acid (TXA) administration and CT scanner type were extracted from the Trauma Audit and Research Network database and hospital electronic records. PE presentation was categorised as immediate (diagnosed on initial trauma scan), early (within 72 hours of admission but not present initially) and late (diagnosed after 72 hours). RESULTS: Of the 2746 trauma patients, 1039 were identified as being admitted to level 2 or 3 care. Forty-eight patients (4.6%) were diagnosed with PE during admission with 14 immediate PEs (1.3%). Of 32.1% patients given TXA, 6.3% developed PE compared with 3.8% without TXA (p=0.08). CONCLUSION: This is the largest study of the incidence of PE in UK MTC patients and describes the greatest number of immediate PEs in a civilian complex trauma population to date. Immediate PEs are a rare phenomenon whose clinical importance remains unclear. Tranexamic acid was not significantly associated with an increase in PE in this population following its introduction into the UK trauma care system.

Advancement of the Harrington technique for reconstruction of pathological fractures of the acetabulum.

A 59-year-old man presented with hip pain secondary to metastatic prostate carcinoma affecting multiple sites, including his left acetabulum. The patient's prognosis was good, he was active, independent, with a good quality of life, so was offered surgical reconstruction. The Harrington method involves passing metal rods from the ileum to the ischium and pubis to create a scaffold for hip replacement. This is the gold standard for reconstruction of acetabular metastatic defects. However, this method is prone to failure by medialisation of the construct in the long term. We present our technique of employing a novel modification to the Harrington reconstruction that offers additional support medially with a suprapectineal plate. This construct is strong and durable enough to facilitate immediate weight-bearing and prevent long-term medialisation.

Bilateral lower limb ischaemia following acetabular reconstruction and arthroplasty.

The incidence of acetabular fractures has increased markedly in patients over 60 in the last quarter of a century, with open reduction and internal fixation being regarded to be the treatment of choice in most patients with displaced acetabular fractures. Lower limb ischaemia following acetabular fixation or arthroplasty is rare. However, such complications can be limb or life threatening, and therefore, it is important to recognise them as early as possible. We present the case of a 70-year-old man with no significant medical history who underwent acetabular fixation with simultaneous arthroplasty complicated with bilateral lower limb ischaemia. We highlight the importance of having a high degree of suspicion which allows early diagnosis and corrective measures to be implemented which can ultimately lead to excellent outcome.

Dual mobility total hip dislocation-femoral stem loosening while attempting closed reduction: a cautionary note.

A 77-year-old man sustained an acetabular fracture after falling from a staircase and landing on his right side. He fractured the anterior column of his acetabulum and the quadrilateral plate. He underwent a single-stage open reduction and internal fixation of the fracture combined with a dual mobility total hip arthroplasty (THA). He sustained a traumatic hip dislocation 1 month postoperatively. Closed reduction was attempted at another hospital, and the femoral stem was pulled out. We believe this was caused by the polyliner being hitched either to the acetabular cup or in the soft tissues around the ilium. We present this case to caution orthopaedic surgeons that dual mobility THA dislocations are difficult to diagnose as the polyliner is not clearly seen on X-rays, and reduction attempts may lead to worsening of an already difficult situation.

Management of the open book APC II pelvis: Survey results from pelvic and acetabular surgeons in the United Kingdom.

The results of this questionnaire show that the opinion of pelvic and acetabular surgeons in the UK and Republic of Ireland vary as to the best method of fixation for APC II pelvic injuries. A single anterior plate and single sacroiliac joint (SIJ) screw was the most popular fixation method, chosen by 34%. 74% favour a single, opposed to two orthogonal anterior plates. Posterior fixation supplementing anterior plating is preferred by 63% of surgeons, 58% use a single versus 42% two SIJ screws. Case by case assessment and intraoperative screening to assess stability is essential when considering whether to stabilise the SIJ.

A retained stitch in time saves 9 - but does it increase the risk of deep prosthetic infection?

INTRODUCTION: During the posterior approach to the hip, the short external rotators are detached and secured with stay sutures. At the time of definitive closure, some surgeons incorporate the initial sutures into their repair while others discard for fresh sutures, presumably as an infection prevention measure. We have conducted a pilot study to investigate whether the incorporation of the primary stay sutures may constitute an infection risk to the patient undergoing a total hip replacement through the posterior approach. MATERIALS AND METHODS: The pilot study was conducted between August 2014 and June 2015. A pair of suture specimens were sent from 25 patients to microbiology, 1 set of primary stay sutures and 1 set of control sutures. All operations were carried out by the senior author through a posterior approach. RESULTS: All specimens were analysed for bacterial and fungal growth, using extended cultures. 1 set of primary sutures had a positive growth, likely from skin contamination; 1 set of control sutures also had a positive growth, likely from environmental contamination. CONCLUSIONS: Our pilot study suggests that the practice of incorporating the primary stay sutures for definitive soft tissue repair of the short external rotators, rather than exchanging them for new sutures, can be deemed safe.

Fix and replace: An emerging paradigm for treating acetabular fractures in older patients.

Acetabular fractures in older patients are challenging to manage. The "fix and replace" construct may present a new paradigm for the management of these injuries. We present the current challenge of acetabular fractures in older patients. We present this in the context of the current literature. This invited editorial presents early results from our centre and the ongoing challenges are discussed.

Adult-onset hypophosphatasia diagnosed following bilateral atypical femoral fractures in a 55-year-old woman.

We report the case of a 55-year-old woman who presented to the emergency department having woken from sleep with right sided thigh swelling. Pelvic radiographs revealed bilateral atypical subtrochanteric femoral fractures (ASFFs). In the two years leading up to this admission, the patient had experienced gradually increasing pain and weakness in her legs which had resulted in a decrease in her mobility from fully mobile to bed-bound. During this time a neurologist had organised a magnetic-resonance imaging (MRI) scan of the brain and spine which was normal. There was no history of bisphosphonate (BP) use. Historical and admission blood tests revealed a persistently low serum alkaline phosphatase (ALP), with all other results within normal limits. The patient was treated with intramedullary nailing of both femurs and histological analysis of bone reamings were characteristic of hypophosphatasia (HPP). The patient was independently mobilising with a walking frame on discharge. Subsequent genetic testing revealed bi-allelic pathogenic variants in the TNSALP gene: c.526G>A, p.(Ala176Thr) and c.1171C>T, p.(Arg391Cys). HPP is an inborn error in metabolism caused by mutation in the gene coding for tissue non-specific alkaline phosphatase (TNSALP), resulting in a decrease in serum ALP concentrations. The age at which it presents which can vary from childhood to middle age, with symptoms ranging from perinatal death to late-onset osteomalacia. In those patients who survive to adulthood, there is a predisposition to fractures, including ASFFs. Treatment with asfotase alfa (a bone-targeted, recombinant human TNSALP) has been approved for perinatal, infantile and paediatric-onset hypophosphatasia. This case emphasises the importance of viewing persistent low ALP as a 'red flag' in patients presenting with musculoskeletal symptoms. Timely diagnosis and treatment of HPP can reduce the risk of serious complications, such as those experienced by this patient.