L4 fixation is not necessary in L5-Iliac spinopelvic fixation after trauma, but coadjutant transilio-transsacral fixation is.

INTRODUCTION: Spinopelvic dissociation (SPD) is a severe injury characterized by a discontinuity between the spine and the bony pelvis consisting of a bilateral longitudinal sacral fracture, most of the times through sacral neuroforamen, and a horizontal fracture, usually through the S1 or S2 body. The introduction of the concept of triangular osteosynthesis has shown to be an advance in the stability of spinopelvic fixation (SPF). However, a controversy exists as to whether the spinal fixation should reach up to L4 and, if so, it should be combined with transiliac-transsacral screws (TTS). OBJECTIVE: The purpose of this study is to compare the biomechanical behavior in the laboratory of four different osteosynthesis constructs for SPD, including spinopelvic fixation of L5 versus L4 and L5; along with or without TTS in both cases. MATERIAL AND METHODS: By means of a formerly described method by the authors, an unstable standardized H-type sacral fracture in twenty synthetic replicas of a male pelvis articulated to the lumbar spine, L1 to sacrum, (Model: 1300, SawbonesTM; Pacific Research Laboratories, Vashon, WA, USA), instrumented with four different techniques, were mechanically tested. We made 4 different constructs in 5 specimen samples for each construct. Groups: Group 1. Instrumentation of the L5-Iliac bones with TTS. Group 2. Instrumentation of the L4-L5-Iliac bones with TTS. Group 3. Instrumentation of L5-Iliac bones without TTS. Group 4: Instrumentation of L4-L5-Iliac bones without TTS. RESULTS AND CONCLUSIONS: According to our results, it can be concluded that in SPD, better stability is obtained when proximal fixation is only up to L5, without including L4 (alternative hypothesis), the addition of transiliac-transsacral fixations is essential.

Cost-effectiveness analysis of the Geriatric Fracture Center (GFC) concept: a prospective multicentre cohort study.

INTRODUCTION: Geriatric Fracture Centers (GFCs) are dedicated treatment units where care is tailored towards elderly patients who have suffered fragility fractures. The primary objective of this economic analysis was to determine the cost-utility of GFCs compared with usual care centres. METHODS: The primary analysis was a cost-utility analysis that measured the cost per incremental quality-adjusted life-year gained from treatment of hip fracture in GFCs compared with treatment in usual care centres from the societal perspective over a 1-year time horizon. The secondary analysis was a cost-utility analysis from a societal perspective over a lifetime time horizon. We evaluated these outcomes using a cost-utility analysis using data from a large multicentre prospective cohort study comparing GFCs versus usual care centres that took place in Austria, Spain, the USA, the Netherlands, Thailand and Singapore. RESULTS: GFCs may be cost-effective in the long term, while providing a more comprehensive care plan. Patients in usual care centre group were slightly older and had fewer comorbidities. For the 1-year analysis, the costs per patient were slightly lower in the GFC group (-$646.42), while the quality-adjusted life-years were higher in the usual care centre group (+0.034). The incremental cost-effectiveness ratio was $18 863.34 (US$/quality-adjusted life-year). The lifetime horizon analysis found that the costs per patient were lower in the GFC group (-$7210.35), while the quality-adjusted life-years were higher in the usual care centre group (+0.02). The incremental cost-effectiveness ratio was $320 678.77 (US$/quality-adjusted life-year). CONCLUSIONS: This analysis found that GFCs were associated with lower costs compared with usual care centres. The cost-savings were greater when the lifetime time horizon was considered. This comprehensive cost-effectiveness analysis, using data from an international prospective cohort study, found that GFC may be cost-effective in the long term, while providing a more comprehensive care plan. A greater number of major adverse events were reported at GFC, nevertheless a lower mortality rate associated with these adverse events at GFC. Due to the minor utility benefits, which may be a result of greater adverse event detection within the GFC group and much greater costs of usual care centres, the GFC may be cost-effective due to the large cost-savings it demonstrated over the lifetime time horizon, while potentially identifying and treating adverse events more effectively. These findings suggest that the GFC may be a cost-effective option over the lifetime of a geriatric patient with hip fracture, although future research is needed to further validate these findings. LEVEL OF EVIDENCE: Economic, level 2. TRIAL REGISTRATION NUMBER: NCT02297581.

The Use of ß-Blockers and the Risk of Undergoing a Knee Arthroplasty: A Nested Case-Control Study.

BACKGROUND: Research has indicated that ß-blockers may downregulate various inflammatory mediators that are involved in osteoarthritis (OA). The objective of this study was to analyze the likelihood of total knee arthroplasty (TKA) among patients with OA who were being treated with ß-blockers. METHODS: A nested case-control study was conducted with use of clinical records from our institutional database. We included patients who attended our outpatient clinic with a history of new-onset knee pain between 2010 and 2019. The case group included individuals who had undergone primary TKA between 2018 and 2019, whereas the control group included subjects who had not undergone TKA. Controls were matched by date of birth ±2 years, sex, calendar time (first outpatient visit ±1 year), and the grade of arthritis; the control-to-case ratio was 1:1. Adherence to ß-blocker use was measured with use of the proportion of days covered (PDC) (i.e.,<0.25, ≥0.25 to <0.75, ≥0.75), and the cumulative effect was measured on the basis of the total number of years of treatment with ß-blockers. A binary logistic regression analysis adjusted to potential confounders was carried out to assess the risk of TKA associated with the intake of ß-blockers. RESULTS: A total of 600 patients were included (300 in the case group and 300 in the control group). Compared with non-users, any use of ß-blockers during the follow-up period was associated with a reduction in the likelihood of undergoing TKA (adjusted odds ratio [OR], 0.51; 95% confidence interval [CI], 0.34-0.77). The adjusted ORs for the use of selective ß1-blockers and nonselective ß1-blockers were 0.69 (95% CI, 0.36 to 1.31) and 0.42 (95% CI, 0.24 to 0.70), respectively. The adjusted ORs for any recent use, PDC of <0.25, PDC of ≥0.25 to <0.75, and PDC of ≥0.75 were 0.65 (95% CI, 0.51 to 0.99), 0.62 (95% CI, 0.21 to 1.85), 0.32 (95% CI, 0.09 to 1.22), and 0.55 (95% CI, 0.34 to 0.88), respectively. Regarding the cumulative effect of ß-blockers, the adjusted ORs for the use for <1 year, ≥1 to <5 years, and ≥5 years were 0.41 (95% CI, 0.20 to 0.85), 0.52 (95% CI, 0.21 to 1.33), and 0.36 (95% CI, 0.22 to 0.60), respectively. CONCLUSIONS: The use of nonselective ß-blockers was associated with a lower likelihood of undergoing TKA. Patients treated for prolonged periods were at a lower likelihood for undergoing TKA. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Geriatric fracture centre vs usual care after proximal femur fracture in older patients: what are the benefits? Results of a large international prospective multicentre study.

OBJECTIVE: The aim of this study was to determine the effect of treatment in geriatric fracture centres (GFC) on the incidence of major adverse events (MAEs) in patients with hip fractures compared with usual care centres (UCC). Secondary objectives included hospital-workflow and mobility-related outcomes. DESIGN: Cohort study recruiting patients between June 2015 and January 2017. Follow-up was 1 year. SETTING: International (six countries, three continents) multicentre study. PARTICIPANTS: 281 patients aged ≥70 with operatively treated proximal femur fractures. INTERVENTIONS: Treatment in UCCs (n=139) or GFCs (n=142), that is, interdisciplinary treatment including regular geriatric consultation and daily physiotherapy. OUTCOME MEASURES: Primary outcome was occurrence of prespecified MAEs, including delirium. Secondary outcomes included any other adverse events, time to surgery, time in acute ward, 1-year mortality, mobility, and quality of life. RESULTS: Patients treated in GFCs (n=142) had a mean age of 81.9 (SD, 6.6) years versus 83.9 (SD 6.9) years in patients (n=139) treated in UCCs (p=0.013) and a higher mean Charlson Comorbidity Index of 2.0 (SD, 2.1) versus 1.2 (SD, 1.5) in UCCs (p=0.001). More patients in GFCs (28.2%) experienced an MAE during the first year after surgery compared with UCCs (7.9%) with an OR of 4.56 (95% CI 2.23 to 9.34, p<0.001). Analysing individual MAEs, this was significant for pneumonia (GFC: 9.2%; UCC: 2.9%; OR, 3.40 (95% CI 1.08 to 10.70), p=0.027) and delirium (GFC: 11.3%; UCC: 2.2%, OR, 5.76 (95% CI 1.64 to 20.23), p=0.002). CONCLUSIONS: Contrary to our study hypothesis, the rate of MAEs was higher in GFCs than in UCCs. Delirium was revealed as a main contributor. Most likely, this was based on improved detection rather than a truly elevated incidence, which we interpret as positive effect of geriatric comanagement. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov: NCT02297581.

Should concurrent infections be treated before performing hip arthroplasty for hip fracture?

AIMS: A systematic literature review focusing on how long before surgery concurrent viral or bacterial infections (respiratory and urinary infections) should be treated in hip fracture patients, and if there is evidence for delaying this surgery. METHODS: A total of 11 databases were examined using the COre, Standard, Ideal (COSI) protocol. Bibliographic searches (no chronological or linguistic restriction) were conducted using, among other methods, the Patient, Intervention, Comparison, Outcome (PICO) template. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for flow diagram and checklist. Final reading of the complete texts was conducted in English, French, and Spanish. Classification of papers was completed within five levels of evidence (LE). RESULTS: There were a total of 621 hits (526 COre; 95 Standard, Ideal) for screening identification, and 107 records were screened. Overall 67 full-text articles were assessed for eligibility, and 21 articles were included for the study question. A total of 46 full-text articles were excluded with reasons. No studies could be included in quantitative synthesis (meta-analyses), and there were many confounding variables including surgeons' experience, prosthesis models used, and surgical technique. CONCLUSION: Patients with hip fracture and with a viral infection in the upper respiratory tract or without major clinical symptoms should be operated on as soon as possible (LE: I-III). There is no evidence that patients with coronavirus disease 2019 (COVID-19) should be treated differently. In relation to pneumonia, its prevention is a major issue. Antibiotics should be administered if surgery is delayed by > 72 hours or if bacterial infection is present in the lower respiratory tract (LE: III-V). In patients with hip fracture and urinary tract infection (UTI), delaying surgery may provoke further complications (LE: I). However, diabetic or immunocompromised patients may benefit from immediate antibiotic treatment. Cite this article: Bone Joint Res 2020;9(12):884-893.

Composition and characteristics of trabecular bone in osteoporosis and osteoarthritis.

BACKGROUND: Bone strength depends on multiple factors such as bone density, architecture and composition turnover. However, the role these factors play in osteoporotic fractures is not well understood. PURPOSE: The aim of this study was to analyze trabecular bone architecture, and its crystal and organic composition in humans, by comparing samples taken from patients who had a hip fracture (HF) and individuals with hip osteoarthritis (HOA). METHODS: The study included 31 HF patients and 42 cases of HOA who underwent joint replacement surgery between 1/1/2013 and 31/12/2013. Trabecular bone samples were collected from the femoral heads and analyzed using a dual-energy X-ray absorptiometry, micro-CT, and solid-state high-resolution magic-angle-spinning nuclear magnetic resonance (MAS-NMR) spectroscopy. RESULTS: No differences in proton or phosphorus concentration were found between the two groups using 1H single pulse, 31P single pulse, 31P single pulse with proton decoupling NMR spectroscopy, in hydroxyapatite (HA) c-axis or a-axis crystal length. Bone volume fraction (BV/TV), trabecular number (Tb.N), and bone mineral density (BMD) were higher in the HO group than in the HF group [28.6% ± 10.5 vs 20.3% ± 6.6 (p = 0.026); 2.58 mm-1 ± 1.57 vs 1.5 mm-1 ± 0.79 (p = 0.005); and 0.39 g/cm2 ± 0.10 vs. 0.28 g/cm2 ± 0.05 (p = 0.002), respectively]. The trabecular separation (Tp.Sp) was lower in the HO group 0.42 mm ± 0.23 compared with the HF group 0.58 mm ± 0.27 (p = 0.036). In the HO group, BMD was correlated with BV/TV (r = 0.704, p < 0.001), BMC (r = 0.853, p < 0.001), Tb.N (r = 0.653, p < 0.001), Tb.Sp (-0.561, p < 0.001) and 1H concentration (-0.580, p < 0.001) in the HO group. BMD was not correlated with BV/TV, Tb.Sp, Tb.Th, Tb.N, Tb.PF, 1H concentration or HA crystal size in the HF group. CONCLUSIONS: Patients with HO who did not sustain previous hip fractures had a higher femoral head BMD, BV/TV, and Tb.N than HF patients. In HO patients, BMD was positively correlated with the BV/TV and Tb.N and negatively correlated with the femoral head organic content and trabecular separation. Interestingly, these correlations were not found in HF patients with relatively lower bone densities. Therefore, osteoporotic patients with similar low bone densities could have significant microstructural differences. No differences were found between the two groups at a HA crystal level.

Editorial. The Challenges of Orthopaedic Trauma in Spain.

Spain is considered the healthiest nation in the world, due to lifepromoting aspects such as good diet, care facilities and a favourable family environment. However, although increased life expectancy is an indicator of development, it may have a negative impact on the other two variables of health service efficiency, namely health expenditure per capita and its relative weight in Gross Domestic Product.

Pin tract infection prophylaxis and treatment.

Pin tract infection in external fixation (ExFix) is a frequent finding which can eventually lead to loosening, osteomyelitis and loss of fixation. Its diagnosis is based on high empiricism and low validity, although it is possible to distinguish between minor and major infection. The first is limited to soft tissues, whereas the latter includes bone involvement. The rate of infection after conversion of external fixation to intramedullary nailing (IMN) is not well known. Unfortunately, papers referring to infection after the conversion of ExFix to intramedullary nailing (IMN) are of evidence level IV or V. It is suggested that conversion of ExFix to IMN should be carried out in a 2 step regimen. The time interval of 2 step regimen is uncertain although some authors have recommended to occur within 9 days. There is no consensus as to which prophylaxis protocol should be applied prior to conversion. In order to throw more light into this important issue, registries capturing important related parameters to the development of infection should be established.

Damage control orthopaedics: State of the art.

Damage control orthopaedics (DCO) originally consisted of the provisional immobilisation of long bone - mainly femur - fractures in order to achieve the advantages of early treatment and to minimise the risk of complications, such as major pain, fat embolism, clotting, pathological inflammatory response, severe haemorrhage triggering the lethal triad, and the traumatic effects of major surgery on a patient who is already traumatised (the "second hit" effect). In recent years, new locations have been added to the DCO concept, such as injuries to the pelvis, spine and upper limbs. Nonetheless, this concept has not yet been validated in well-designed prospective studies, and much controversy remains. Indeed, some researchers believe the indiscriminate application of DCO might be harmful and produce substantial and unnecessary expense. In this respect, too, normalised parameters associated with the acid-base system have been proposed, under a concept termed early appropriate care, in the view that this would enable patients to receive major surgical procedures in an approach offering the advantages of early total care together with the apparent safety of DCO. This paper discusses the diagnosis and treatment of severely traumatised patients managed in accordance with DCO and highlights the possible drawbacks of this treatment principle.

Development of trauma systems in Europe-reports from England, Germany, the Netherlands, and Spain.

Major trauma systems have evolved in many European countries and have resulted in improved care in terms of mortality and morbidity. Many of the systems have similar history, with reports of either poor services, or a single disaster, driving change of policy and set up. We report on 4 European systems, looking at the background, set up and some of the results. Similar issues are identified including the importance of triage, the concentration of specialist skills which require patients to bypass hospitals, and the standardization of treatment protocols. The issues of rehabilitation and the increasing importance of measuring outcome with patient reported metrics are discussed.

Assessing bone quality through mechanical properties in postmenopausal trabecular bone.

BACKGROUND: The inner structure of trabecular bone is a result of structural optimization provided by remodeling processes. Changes in hormonal status related to menopause cause bone tissue loss and micro-architectural deterioration with a consequent susceptibility to fracture. Accumulation of micro-damage in bone, as a function of the rate of production and rate of repair, underlies the development of stress fractures, increasing fragility associated to age and osteoporosis, especially in transmenopausal women. PATIENTS AND METHODS: Quasi-static and nano-dynamic mechanical characterization were undertaken in trabecular bone from femoral neck biopsies of postmenopausal women. AFM (Atomic Force Microscopy) complementary studies were performed to determine nano-roughness (SRa) and the fibrils width of collagen. Nanoindentations were used to quantify transmenopausal changes in intrinsic mechanical properties of trabecular bone: hardness (Hi), modulus of Young (Ei), complex modulus (E*), tan delta (δ), storage modulus (E') and loss modulus (E"). RESULTS: As result of the quasi-static measurements, 0.149 (0.036) GPa and 2.95 (0.73) GPa of Hi and Ei were obtained, respectively. As result of the nano-dynamic measurements, 17.94 (3.15), 0.62 (0.10), 13.79 (3.21 and 6.39 (1.28) GPa of E*, tan (δ), E' and E" were achieved, respectively. 101.07 SRa and 831.28 nm of fibrils width were additionally obtained. CONCLUSIONS: This study poses a first approach to the measurement of bone quality in postmenopausal trabecular bone by combining quasi-static, nano-DMA analysis and tribology of dentin surface through AFM characterization.

Biochemical assessment of nanostructures in human trabecular bone: Proposal of a Raman microspectroscopy based measurements protocol.

BACKGROUND: Improvements to the understating of the compositional contributions of bone mineral and organic components to the competence of trabecular bone are crucial. The purpose of this study was to propose a protocol to study biochemical composition of trabecular bone, based on two combined Raman analysis methodologies. MATERIAL AND METHODS: Both cluster and single point Raman mappings were obtained, in order to assess bone degeneration associated with aging, disease, or injury, and to help in the evaluation and development of successful therapies. In this study, human trabecular bone has been analysed throughout a) Raman cluster analysis: bone mineral content, carbonate-to-phosphate ratio (both from the mineral components), the crosslinking and nature/secondary structure of collagen (both from the organic components); and b) Single point Raman spectra, where Raman points related to the minerals and organic components were also obtained, both techniques were employed in spectra attained at 400 to 1700 cm-1. RESULTS: Multivariate analysis confirmed: 1) the different spectral composition, 2) the existence of centroids grouped by chemical affinity of the various components of the trabecular bone, and 3) the several traces of centroids and distribution of chemical compositional clusters. CONCLUSIONS: This study is important, because it delivers a study protocol that provides molecular variations information in both mineral and collagen structure of trabecular bone tissue. This will enable clinicians to benefit knowing the microstructural differences in the bone subjected to degeneration of their patients.

Surgical Infection after Posterolateral Lumbar Spine Arthrodesis: CT Analysis of Spinal Fusion.

OBJECTIVE: To determine the incidence of infection after instrumented lumbar spine surgery, the demographic and surgical variables associated with acute infection, and the influence of infection and debridement on the consolidation of spinal fusion. METHODS: After obtaining approval from the hospital ethics committee, an observational study was made on a prospective cohort of consecutive patients surgically treated by posterolateral lumbar spine arthrodesis (n = 139, 2005-2011). In all cases, the minimum follow-up period was 18 months. The following bivariate analysis was conducted of demographic and surgical variables: non-infection group (n = 123); infection group (n = 16). Fusion rates were determined by multislice CT. Logistic regression analysis was performed. RESULTS: Incidence of deep infection requiring debridement: 11.51% (95% confidence interval, 5.85-17.18]). Bivariate analysis: differences were observed in hospital stay (7.0 days [range, 4-10] vs 14.50 days [range, 5.25-33.75]; P = 0.013), surgical time (3.15 h vs 4.09 h; P = 0.004), body mass index (25.11 kg/m2 [22.58-27.0] vs 26.02 kg/m2 [24.15 to 29.38]; P = 0.043), Charlson comorbidity index (median, 0 vs 1; P = 0.027), and rate of unsuccessful consolidation according to CT (18.4% vs 72.7%; P = 0.0001). In a model of multivariate logistic regression, taking as the dependent variable unsuccessful arthrodesis after 1 year, and adjusting for the other independent variables (infection, body mass index, Charlson comorbidity index, and surgical time), the only variable that was significantly associated with an outcome of unsuccessful spinal fusion after 1 year was infection, with OR = 12.44 (95% confidence interval, 2.50-61.76). CONCLUSION: Deep infection after instrumented lumbar spine arthrodesis is a common complication that compromises the radiographic outcome of surgery. Patients who develop a postoperative infection and require debridement surgery are 12 times less likely to achieve satisfactory radiological fusion.

Spinopelvic injuries. Facts and controversies.

Spinopelvic injuries result from high energy trauma with overloading through the sacrum. These lesions can accomplish either bone fractures, ligament injuries or, most commonly, both. They may be accompanied with other associated life threatening injuries and cause biomechanical instability with potential fracture non-union, mal-union and subsequent lifetime pain and disability. Surgical stabilization of spinopelvic injuries requires planning in order to apply the appropriate osteosynthesis principles (compression; neutralization; buttressing and tension band). In general terms simple sacral fractures can be treated under compression by iliosacral screws. However, as more complex ones cannot be compressed, they need vertical support and neutralization of shearing forces (neutralization and buttressing principles). For that purpose, spinopelvic instrumentations appear to be the current appropriate technique of stabilization. In the herein paper the general principles of sacral fracture osteosynthesis are discussed, as well as its application to spinopelvic injuries. Controversies on positioning, surgical approach, per-operative traction, sacral laminectomy, type of biomechanical construct, length of fixation, screws length, mode of weight bearing, and osteosynthesis hardware removal are discussed.

Inter-individual gene variants associated with trabecular bone plasticity: A step forward in the personal genomics of degenerative bone disease.

Continuing tissue destruction in osteoarthrosis is maintained by molecular pathways related to an unbalanced chondrocyte metabolism, the loss of reactive oxygen species (ROS) homeostasis, increase catabolism in a degraded matrix and the limited response to growth factors due to cell aging. Rare deleterious gene variants driving relevant molecular pathways may play a key role in the pathogenesis and genetic control of common diseases and may also influence the common gene variants observed in GWAS. We use molecular profiling technologies based on massive sequencing of genes to interrogate clinical samples for a variety of molecules involved in the pathogenesis pathways of OA and also to derive new insights for drug targeting discovery at an early stage of the disease. By whole-exome sequencing performed in OA patients with extreme phenotypes and in non-related individuals without clinical evidence of OA, the most predominant of the rare gene variants found were non-synonymous single-nucleotide variants (SNV) from exonic DNA regions and with missense functional effects predicting a moderate impact on protein function. A total of 629, 577, and 639 gene variants for the TPF, COA, and ANHNF patients, respectively, were found not to be shared with the 20 non-disease-related individuals. After subtraction of the 306 variants shared among the OA patients, we obtained the individual profiles of 323, 271, and 333 gene variants, for the TPF, COA, and ANHNF patients, respectively. After filtering by the bioinformatics, genetic, and biological criteria established to assess the clinical consequences, comparative analysis of trio sequences using integrative genome visualization tool clearly demonstrate the differences between patients. Analysis of the collagen gene variants identified 78, 20, and 43 genetic collagen variants for the three extreme phenotypes. Rare gene variants encoding for proteins that are less abundant in the trabecular bone matrix, together with those responsible for the control and regulation of bone turnover and plasticity of subchondral trabecular bone, play important roles in OA and help to define the clinical phenotype.

Nanostructure in the trabecular bone of postmenopausal women: Mechanical and chemical analysis.

The possibility of diagnosis and prediction of multiple disorders in trabecular bone through nano-biomechanics and chemical analysis are summarized. Improvements to the understating of the compositional contributors of bone mineral and organic components to mechanical competence are crucial. Viscoelastic properties and Raman characterization have been used to evaluate possible alterations of the trabecular bone associated with aging, disease, or injury. In this study, the trabecular bone of postmenopausal women has been analyzed throughout. (a) Nanomechanical characterization, by using nano-DMA: complex modulus, tan δ, loss modulus (E'), and storage modulus (E'); and (b) Raman analysis: relative presence of minerals, carbonate-to-phosphate ratio (both from the mineral components), the crosslinking and nature/secondary structure of collagen (both from the organic components). Complementary nano-morphological studies were done assessing roughness (SRa) and collagen fibrils width, on this trabecular bone. A general idea of the behavior of the viscoelastic performance can be obtained by the Tan δ (E″/E'), that achieved 0.98GPa of damping. 249nm and 0.898µm of SRa roughness and fibrils width were obtained, respectively. The relative presence of minerals, the carbonate-to-phosphate ratio, the crosslinking and the nature/secondary structure of collagen, between 700 and 1700cm-1, were also obtained, in order to propose a study protocol for trabecular bone characterization.

Floating hip and associated injuries.

AIM: To describe our experience in treating patients diagnosed with floating hip injury and to communicate the outcomes achieved and the rate of complications. A secondary aim is to compare the results of this group in terms of quality of life with those of patients presenting with a fracture either of the pelvis or of the acetabulum, but in which the femoral segment is not involved. PATIENTS AND METHODS: This is a descriptive study of the patients diagnosed with floating hip injury (25 patients) who were treated at our hospital between 2004 and 2007, with a minimum follow-up of seven years. The results are compared with those of a control group of 56 patients diagnosed with an isolated pelvic or acetabular injury. We describe the injuries and the associated lesion. The patients' quality of life was assessed using the EUROQOL tool. RESULTS: Among the floating hip group of patients, three suffered an additional arterial lesion and were later treated with a supracondylar amputation. Seven patients presented heterotopic ossification. No significant difference was observed between the study and control groups, according to the EUROQOL tool, although the scores for every dimension were lower among the floating hip patients. Among the patients in the control group, the quality of life scores were also affected in every dimension of the EUROQOL scale. DISCUSSION AND CONCLUSIONS: The addition of a femoral fracture to a pelvic or acetabular injury, the so-called floating hip, is a devastating injury which has an important impact on patients' quality of life, going beyond that experienced by patients with isolated injuries. Nevertheless, our results did not reflect statistically significant differences in the quality of life among the three groups analyzed: isolated fractures, floating hip and floating hip resulting in amputation.

Severe tibial plateau fractures (Schatzker V-VI): open reduction and internal fixation versus hybrid external fixation.

Tibial plateau fractures (TPF) are highly prone to complications and adverse effects. Their treatment has long been a matter of controversy, as fracture patterns and possible damage to soft tissues can easily aggravate complications. On the one hand, open reduction and internal fixation (ORIF) techniques provide a good approach to joint shape restoration and biomechanics, but they may also provoke a higher rate of soft-tissue complications. On the other, hybrid external fixation (HEF), although allowing little facility for reduction, may, theoretically, produce much less damage to the soft tissues. We present 93 cases of TPF classified as type V or VI that were followed up for at least 24 months. There were no statistical differences among them in relation to consolidation, secondary malalignment or range of motion, according to whether ORIF or HEF was employed. However, when external fixation followed open reduction, both superficial and deep-infection rates were higher.