Human femur fracture by mechanical compression: Towards the repeatability of bone fracture acquisition.

The increase in life expectancy combined with greater bone fragility over the years is causing a rise in the bone fracture cases. Femur fractures are the most important due to their high mortality rate. This multidisciplinary work is carried out in this context and focuses on the experimental reproduction of human femur fractures by compression. We describe a sequence of steps supervised by orthopaedic surgeons for the correct arrangement of specimens on the system set up to perform the experiment. The device applies force by compression until the human bone is fractured. All tests performed have been monitored and evaluated from different knowledge perspectives. The results obtained have demonstrated the repeatability of the fracture type in a controlled environment as well as identifying the main features involved in this process. In addition, the fractured bones have been digitized to analyze the fracture zone to recreate and evaluate future simulations.

Development of appropriateness criteria for hip arthroscopy in patients with femoroacetabular impingement. / Desarrollo de criterios de uso adecuado para la artroscopia de cadera en pacientes con choque femoroacetabular.

INTRODUCTION: The use of hip arthroscopy as a treatment for femoroacetabular impingement (FAI) has increased exponentially in recent years without robust evidence or consensus about the patients who benefit from it. OBJECTIVE: To develop explicit criteria for the appropriate indication of hip arthroscopy in FAI. METHOD: A panel of experts was formed with 11 traumatologists following the RAND/UCLA method to identify the appropriateness criteria for hip arthroscopy in patients with FAI. The panel made independent evaluations of each indication using a nine-point adequacy scale, then met face-to-face to vote using an iterative discussion process. The influence of the variables on the final score was studied using multinomial logistic regression models. The Classification and Regression Tree (CART) analysis was used to summarize the results in the form of decision trees. RESULTS: Twenty-three point four percent of the 192 scenarios evaluated in the face-to-face meeting was considered appropriate (40% agreement), 26.6% uncertain and 50% inappropriate (75% agreement). The most influential variables in considering the use of arthroscopy appropriate were: joint symptoms compatible with shock test, duration of symptoms, functionality, age and Hip Outcome Score (HOS) scale. CONCLUSIONS: We developed an explicit set of criteria for the appropriate use of hip arthroscopy in FAI using the RAND/UCLA method, providing a tool that would identify patients who are potential candidates for surgical treatment using arthroscopic hip surgery.

Chondrocytes extract from patients with osteoarthritis induces chondrogenesis in infrapatellar fat pad-derived stem cells.

OBJECTIVE: Infrapatellar fat pad of patients with osteoarthritis (OA) contains multipotent and highly clonogenic adipose-derived stem cells that can be isolated by low invasive methods. Moreover, nuclear and cytoplasmic cellular extracts have been showed to be effective in induction of cell differentiation and reprogramming. The aim of this study was to induce chondrogenic differentiation of autologous mesenchymal stem cells (MSCs) obtained from infrapatellar fat pad (IFPSCs) of patients with OA using cellular extracts-based transdifferentiation method. DESIGN: IFPSCs and chondrocytes were isolated and characterized by flow cytometry. IFPSCs were permeabilized with Streptolysin O and then exposed to a cell extract obtained from chondrocytes. Then, IFPSCs were cultured for 2 weeks and chondrogenesis was evaluated by morphologic and ultrastructural observations, immunologic detection, gene expression analysis and growth on 3-D poly (dl-lactic-co-glycolic acid) (PLGA) scaffolds. RESULTS: After isolation, both chondrocytes and IFPSCs displayed similar expression of MSCs surface makers. Collagen II was highly expressed in chondrocytes and showed a basal expression in IFPSCs. Cells exposed to chondrocyte extracts acquired a characteristic morphological and ultrastructural chondrocyte phenotype that was confirmed by the increased proteoglycan formation and enhanced collagen II immunostaining. Moreover, chondrocyte extracts induced an increase in mRNA expression of chondrogenic genes such as Sox9, L-Sox5, Sox6 and Col2a1. Interestingly, chondrocytes, IFPSCs and transdifferentiated IFPSCs were able to grow, expand and produce extracellular matrix (ECM) on 3D PLGA scaffolds. CONCLUSIONS: We demonstrate for the first time that extracts obtained from chondrocytes of osteoarthritic knees promote chondrogenic differentiation of autologous IFPSCs. Moreover, combination of transdifferentiated IFPSCs with biodegradable PLGA 3D scaffolds can serve as an efficient system for the maintenance and maturation of cartilage tissue. These findings suggest its usefulness to repair articular surface in OA.

Low-energy spontaneous femoral fractures in patients with long-term bisphosphonate therapy.

Long-term bisphosphonate therapy has been associated with low-energy subtrochanteric and femoral diaphyseal fractures in recent reports. We report three cases of a characteristic pathologic fracture of the subtrochanteric part of femoral, one of them bilateral.

Effect of vitamin C on fracture healing in elderly Osteogenic Disorder Shionogi rats.

We studied the effect of vitamin C on fracture healing in the elderly. A total of 80 elderly Osteogenic Disorder Shionogi rats were divided into four groups with different rates of vitamin C intake. A closed bilateral fracture was made in the middle third of the femur of each rat. Five weeks after fracture the femora were analysed by mechanical and histological testing. The groups with the lower vitamin C intake demonstrated a lower mechanical resistance of the healing callus and a lower histological grade. The vitamin C levels in blood during healing correlated with the torque resistance of the callus formed (r = 0.525). Therefore, the supplementary vitamin C improved the mechanical resistance of the fracture callus in elderly rats. If these results are similar in humans, vitamin C supplementation should be recommended during fracture healing in the elderly.

Dietary fat intake and the risk of osteoporotic fractures in the elderly.

OBJECTIVE: To explore the association between fat intake, serum lipids and the risk of osteoporotic fractures in the elderly. DESIGN: A hospital-based case-control study. SETTING: The study was conducted at a tertiary centre and referral hospital for the province of Jaén (Spain). SUBJECTS: Cases (n=167) were patients aged 65 years or more with a low-energy fracture selected from the population attended at the hospital. Controls (patients without antecedents of any fracture) were 1:1 matched to cases by sex and age (n=167). METHODS: Diet was assessed by a semiquantitative food frequency questionnaire. Serum total cholesterol and high-density lipoprotein (HDL) cholesterol were also measured. RESULTS: Participants in the two upper quartiles of polyunsaturated fat (PUFA) intake showed an increased risk of fracture, with statistically significant differences with respect to the first quartile in the adjusted model (odds ratio (OR)=3.59; 95% confidence interval (CI)=1.06-12.1 and OR=5.88; 95% CI=1.38-25.02); P=0.01 for the trend test). A higher ratio of monounsaturated fat (MUFA) to PUFA was associated with a reduced risk of fracture (OR=0.20; 95% CI=0.07-0.60 for the fourth quartile; P=0.002 for the trend test). The intake of omega-6 fatty acids was associated with an elevated risk of fracture (OR=3.41; 95% CI=1.05-11.15 for the fourth quartile; P=0.01 for the trend test). HDL-cholesterol levels were inversely associated with the risk of fracture (test for trend P=0.03 across quartiles). CONCLUSIONS: PUFA intake was associated with an increased risk of osteoporotic fractures in the elderly, whereas a high ratio of MUFA:PUFA was associated with decreased risk.

Clonidine decreases intraoperative bleeding in middle ear microsurgery.

BACKGROUND: The antihypertensive drug clonidine is a centrally acting alpha2 agonist useful as a premedicant because of its sedative, anxiolytic, and analgesic properties. We examined the effect of clonidine given as an oral preanesthetic medication in producing a bloodless surgical field in patients undergoing middle ear microsurgery. We also evaluated whether the administration of clonidine would alter the reflex cardiovascular response to laryngoscopy and endotracheal intubation, anesthetic requirement, postoperative pain intensity and consumption of analgesics, and pre- and postoperative sedation and anxiety. METHODS: A prospective, randomized, double-blind clinical trial was performed in 40 patients scheduled for elective middle ear surgery under general anesthesia. Twenty-one patients received clonidine (300 microg p.o.) 90 min prior to arrival at the operating theater and 19 received placebo (control group). The hemodynamic endpoint of the anesthetic management was maintenance of hypotension for producing a bloodless surgical field. The desired control of the cardiovascular system was attained with isoflurane (inspired concentration increments of 0.25 vol% up to a maximum of 1.5 vol%)+/-fentanyl (bolus of 1 microg. kg-1)+/-urapidil (bolus of 0.3 mg. kg-1) as needed. Intraoperative bleeding was assessed on a four-point scale from 0=no bleeding to 3=abundant bleeding. RESULTS: There was less bleeding in the clonidine group (mean+/-SEM) than in the control group (0.75+/-0.3 vs 1.1+/-0.4, P<0.05). Patients given clonidine required a mean inspired isoflurane concentration of 0.63+/-0.1 vol% as compared with 1.01+/-0.2 vol% in controls (P<0.05). Fentanyl requirements were also significantly lower (57.10 vs 79.42 microg. kg-1, P<0.05). Four clonidine-treated patients required urapidil to achieve satisfactory hypotension as compared with 11 controls (P<0.05). Clonidine attenuated the associated cardiovascular response following laryngoscopy and intubation, and was more effective than placebo in achieving a satisfactory preoperative sedation and decreasing intensity of postoperative pain. Preoperative anxiety and incidence of adverse events was similar in both groups. CONCLUSION: Premedication with clonidine reduced bleeding in middle ear microsurgery, attenuated hyperdynamic response to tracheal intubation, and reduced isoflurane, fentanyl, and urapidil requirements for controlled hypotension.

Reproducibility of patellofemoral CT scan measurements.

At least seven parameters have been described for the measurement of patellofemoral malalignment on CT scanning; three of which measure lateral patellar tilt, two lateral patellar shift and two femoral trochlear dysplasia. We studied 22 knees in 18 patients complaining of patellofemoral pain in order to investigate the reproducibility of these methods. CT scans of the patellofemoral joint were performed in each knee at 0 degrees and 20 degrees of flexion. The seven parameters were recorded from each scan by three independent observers in a blind study. The reproducibility was studied by means of the intraclass correlation coefficient (ICC). Parameters measuring lateral patellar tilt showed excellent reliability (ICC>75%). The measurements of lateral patellar shift and femoral trochlear dysplasia showed a fair or poor correlation (ICC<75%). We suggest that parameters for measuring lateral patellar tilt only should be used from CT scanning when planning treatment for patello-femoral malalignment.

Effect of 25-OH-vitamin D on fracture healing in elderly rats.

To investigate the effect of 25-OH-vitamin D supplements (calcidiol) on fracture healing in the elderly, an experimental model with 15 18-month-old female Wistar rats was designed. An experimental fracture in the middle third of both femora of each rat was made. Then the rats were randomly assigned to two groups: one group was subcutaneously treated with 25-OH-vitamin D during all healing processes, and the other group (the control group) was not. After 5 weeks of healing, the animals were killed and both femora were extracted. Blood samples were collected before fracture and at death to determine the levels of 25-OH-vitamin D. All bones that were extracted were subjected to a torsion test to assess healing; a significantly greater maximum shear force before failure was supported in the treated group (p < 0.01). Moreover, a positive correlation (p < 0.01; r=0.55) was found between blood levels of 25-OH-vitamin D at death and the mechanical strength of the callus. Thus, the administration of 25-OH-vitamin D after the experimental fracture significantly improved the mechanical strength of the fractured bone. If similar results are found in the human, then treatment with 25-OH-vitamin D after the occurrence of a fracture would be a good way to improve fracture healing in the elderly.

Value of the carpal compression test in the diagnosis of carpal tunnel syndrome.

In order to determine the efficacy of the carpal compression test (CCT) in the diagnosis of the carpal tunnel syndrome (CTS), we conducted a prospective study on 200 consecutive hands diagnosed as having CTS. A control group of 100 healthy volunteers with no symptoms of CTS were also assessed. The results of the CCT in the patients and controls were compared with those obtained with Phalen's and Tinel's tests. CCT achieved a sensitivity of 87%, and a specificity of 95%. It is a simple, fast and very reliable provocative test, and should be routinely used in the diagnosis of CTS. This test is also an appropriate manoeuvre in wrists with limited range of motion or pain that cannot be assessed with Phalen's wrist flexion test.

CT scanning of the patellofemoral joint. The quadriceps relaxed or contracted?

A study of the patellofemoral joint in patients with patellofemoral pain has been carried out in 14 patients (18 knees) to compare CT scans with the knee extended fully and the quadriceps muscle contracted or relaxed. The purpose was to decide whether both examinations are necessary in young adults with suspected patellar malalignment. The patients were selected randomly. Thirteen knees were also examined in 20 degrees of flexion. The lateral patellar angle and the lateral patellar shift were measured. Linear regression analysis showed a proportional relationship between measurement with the quadriceps contracted and relaxed. Therefore, only one examination is needed and is easier to carry out in the relaxed state. Radiation to the patient and costs are reduced.

Congenital pseudarthrosis of the tibia.

The present concepts of the aetiology, prevention and treatment of congenital pseudarthrosis of the tibia are discussed. The satisfactory results of Ilizarov's method and vascularised fibular grafting make these methods optimal choices for treatment. When they are not available, a bone graft with intramedullary fixation is a valuable alternative.

Effects of medial prefrontal cortex stimulation on the spontaneous activity of the ventral pallidal neurons in the rat.

The neural connections from the medial prefrontal cortex to the ventral pallidum were investigated in urethane-anesthetized rats. Extracellular recordings were made from 124 spontaneously firing neurons in the ventral pallidum while the medial prefrontal cortex was electrically stimulated. The most frequent response to prefrontal cortex stimulation was inhibition of the firing rate of 72.3% of the neurons with orthodromic response (mean latency: 14.4 +/- 1.6 ms). Excitatory responses were found in 27.7% of the neurons with orthodromic response (mean latency: 8.5 +/- 1.4 ms). Frequency histograms of latencies were unimodal in both types of responses. Fifty-nine neurons (47.6% of the total tested) showed no change in spontaneous firing after medial prefrontal cortex stimulation. The electrophysiological results support previous anatomical findings of connections between the medial prefrontal cortex and the ventral pallidum. These projections play a predominantly inhibitory role in the spontaneous activity of ventropallidal neurons, and show topographical organization. This inhibition may modulate the motor performance of motivated behaviors.