A preliminary study in classification of the severity of spine deformation in adolescents with lumbar/thoracolumbar idiopathic scoliosis using machine learning algorithms based on lumbosacral joint efforts during gait.

To assess the severity and progression of adolescents with idiopathic scoliosis (AIS), radiography with X-rays is usually used. The methods based on statistical observations have been developed from 3D reconstruction of the trunk or topography. Machine learning has shown great potential to classify the severity of scoliosis on imaging data, generally on X-ray measurements. It is also known that AIS leads to the development of gait disorder. To our knowledge, machine learning has never been tested on spine intervertebral efforts during gait as a radiation-free method to classify the severity of spinal deformity in AIS. Develop automated machine learning algorithms in lumbar/thoracolumbar scoliosis to classify the severity of spinal deformity of AIS based on the lumbosacral joint (L5-S1) efforts during gait. The lumbosacral joint efforts of 30 individuals with lumbar/thoracolumbar AIS were used as distinctive features fed to the machine learning algorithms. Several tests were run using various classification algorithms. The labeling consisted of three classes reflecting the severity of scoliosis i.e. mild, moderate and severe. The ensemble classifier algorithm including k-nearest neighbors, support vector machine, random forest and multilayer perceptron achieved the most promising results, with accuracy scores of 91.4%. This preliminary study shows lumbosacral joint efforts can be used to classify the severity of spinal deformity in lumbar/thoracolumbar AIS. This method showed the potential of being used as an assessment tool to follow-up the progression of AIS as a radiation-free method, alternative to radiography. Future studies should be performed to test the method on other categories of AIS.

Is simultaneous bilateral total hip arthroplasty deleterious in a biomechanical point of view? A comparative gait analysis study.

PURPOSE: Uni- or bilateral hip osteoarthritis is a common disease generating pain, stiffness, and functional disabilities. Changes in the normal walking with higher energy expenditures are observed. Facing a cruel lack of biomechanical data, we decided to analyse the impact on the walking of single and simultaneous bilateral total hip arthroplasties (THA). METHOD: We conducted a prospective monocentric study, comparing two matched groups of 15 patients able to walk with symptomatic isolated uni- (group 1) or bilateral HO (group 2) and treated respectively by unilateral THA (UTHA) or simultaneous bilateral THA (SBTHA). Surgery was performed by a single surgeon with a direct anterior approach and approved by local ethical committee. Walking was assessed by a « 3D Gait analysis motion¼ pre and at 6 months post operatively. RESULT: In the UTHA group, recovery, i.e., efficiency of locomotor mechanism (p < 0.001) and pelvis sagittal balance (p = 0.031) improved, while external and total work (p = 0.010) decreased post operatively. In the SBTHA group, speed (p = 0.035), step length (p = 0.046), range of motion of knee sagittal stance (p = 0.009) and hip frontal (p = 0.031), and internal work are significatively higher (p < 0.001) post operatively. CONCLUSIONS: This original study attests that THA has a positive impact on walking and energetics outcome in UTHA and SBTHA.

Survey regarding prevention of surgical site infection after orthopaedic surgery in Belgium: are we on the right track?

Prevention strategies are essential to reduce the rate of surgical site infection (SSI) in orthopaedic surgery. Members of the Royal Belgian Society for Orthopaedic Surgery and Traumatology (SORBCOT) and the Belgische Vereniging voor Orthopedie en Traumatologie (BVOT) were asked to answer a 28-question questionnaire on the internet about the application of surgical antimicrobial prophylaxis measures and to compare them with current inter- national recommendations. 228 practicing orthopedic surgeons responded to the survey from different regions (Flanders, Wallonia and Brussels), different hospitals (university, public and private), different levels of experience (< 5 years, 5 to 10 years and > 10 years) and different subspecialties (lower limb, upper limb and spine). Regarding the questionnaire: 7% systematically perform a dental check-up. 47.8% of the participants never carry out a urinalysis, 41.7% when the patient presents symptoms and 10.5% carry it out systematically. 2.6% systematically propose a pre-operative nutritional assessment. 5.3% of respondents suggest stopping biotherapies (Remicade®, Humira®, rituximab®, etc.) before an operation and 43.9% do not feel comfortable with this type of treatment. 47.1% suggest smoking cessation before the operation and 22% of them advise smoking cessation for a period of 4 weeks. 54.8% never carry out MRSA screening. 68.3% systematically per- formed hair removal, 18.5% when the patient had hirsutism. Among them, 17.7% use shaving with razors. Alcoholic Isobetadine is the most used product with 69.3% when disinfecting the surgical site. 42.1% of the surgeons chose a delay between the injection of antibiotic prophylaxis and the incision of less than 30 minutes, 55.7% between 30 and 60 minutes and 2.2% between 60 and 120 minutes. However, 44.7% did not wait for the injection time to be respected before incising. An incise drape is used in 79.8% of cases. The response rate was not influenced by the surgeon's experience. Most international recommendations in terms of prevention of surgical site infection are correctly applied. However, some bad habits are maintained. These include the use of shaving for depilation and the use of non-impregnated adhesive drapes. Practices that could be improved include management of treatment in patients with rheumatic diseases, a 4-week smoking cessation period, and treating positive urine tests only when symptomatic.

Touch® double mobility arthroplasty for trapeziometacarpal osteoarthritis: outcomes for 92 prostheses.

Trapeziometacarpal prostheses have been used in the treatment of first carpometacarpal joint osteoarthritis for many years. No studies have demonstrated statistical superiority over gold-standard trapeziectomy, but they have been proved to enable shorter convalescence, better pain relief and faster functional recovery. The aims of the present study were to report functional results in a large cohort treated with the Touch® new-generation dual mobility trapeziometacarpal prosthesis, with comparison to results in the literature. A retrospective study included 92 Touch® prostheses. Assessment comprised pre- and post-operative pain, QuickDASH score and satisfaction rate. Mean follow-up was 1.33 ± 0.4 years. Pain significantly improved after surgery. Functional QuickDASH scores did not significantly differ from those reported in the age-matched general population. Return to work was fast, at 2.6 months. Satisfaction scores were high. There were no major complications such as dislocation, fracture or loosening, but the rate of De Quervain's tenosynovitis was higher than in other studies. The Touch® prosthesis appeared to be a safe and stable implant, providing good satisfaction and very good functional scores and fast return to work and leisure activity. Considering the high rate of postoperative De Quervain's tenosynovitis, we suggest opening the first sheath of the extensors tendons while positioning the prosthesis.

Predicting physical activity recovery after hip and knee arthroplasty? A longitudinal cohort study.

BACKGROUND: Recovery of physical activity (PA) after telerehabilitation following knee and hip arthroplasty (TKA-THA) has rarely been studied. An improved understanding of PA recovery is needed, as it could be influenced by many factors such as age, gender or pre-operative physical function. OBJECTIVES: To assess PA recovery weekly for 3 months after TKA-THA and to determine perioperative factors that could help predict PA recovery at 3 months. METHODS: From one week before until 3 months after surgery, 132 patients wore a fitness tracker continuously. Each patient received personalized and daily exercises and feedback through a tablet. Before and after surgery, patient-reported outcome measures of symptoms, pain, activities of daily living and quality of life were recorded. A one-way repeated-measure ANOVA was used to assess the time effect on step count for each post-operative week. To predict the absolute step count at 3 months post-surgery, a backward multiple linear regression was used. RESULTS: Patients reached their pre-operative PA level at week 7, with no significant additional improvement by 3 months post-surgery. Pre-operative step count, the number of days using crutches and pre-operative symptoms explained 35% of the variability of step count at 3 months. CONCLUSION: This patient population receiving telerehabilitation reached their pre-operative PA level at 7-week post-surgery with no further improvement over the subsequent 5 weeks. The PA level at 3 months could be predicted by pre-operative step count, duration of crutches use, and pre-operative symptoms.

Biomechanical study of a low-cost external fixator for diaphyseal fractures of long bones.

BACKGROUND: External fixation improves open fracture management in emerging countries. However, sophisticated models are often expensive and unavailable. We assessed the biomechanical properties of a low-cost external fixation system in comparison with the Hoffmann® 3 system, as a reference. METHODS: Transversal, oblique, and comminuted fractures were created in the diaphysis of tibia sawbones. Six external fixators were tested in three modes of loading-axial compression, medio-lateral (ML) bending, and torsion-in order to determine construction stiffness. The fixator construct implies two uniplanar (UUEF1, UUEF2) depending the pin-rods fixation system and two biplanar (UBEF1, UBEF2) designs based on different bar to bar connections. The designed low-cost fixators were compared to a Hoffmann® 3 fixator single rod (H3-SR) and double rod (H3-DR). Twenty-seven constructs were stabilized with UUEF1, UUEF2, and H3-SR (nine constructs each). Nine constructs were stabilized with UBEF1, UBEF2, and H3-DR (three constructs each). RESULTS: UUEF2 was significantly stiffer than H3-SR (p < 0.001) in axial compression for oblique fractures and UUEF1 was significantly stiffer than H3-SR (p = 0.009) in ML bending for transversal fractures. Both UUEFs were significantly stiffer than H3-SR in axial compression and torsion (p < 0.05), and inferior to H3-SR in ML bending, for comminuted fractures. In the same fracture pattern, UBEFs were significantly stiffer than H3-DR (p = 0.001) in axial compression and torsion, while only UBEF1 was significantly stiffer than H3-DR in ML bending (p = 0.013). CONCLUSIONS: The results demonstrated that the stiffness of the UUEF and UBEF device compares to the reference fixator and may be helpful in maintaining fracture reduction. Fatigue testing and clinical assessment must be conducted to ensure that the objective of bone healing is achievable with such low-cost devices.

Frequency and risk factors of complications after surgical treatment of ankle fractures : a retrospective study of 433 patients.

Ankle fractures are frequently treated using surgical interventions, and are associated with a high rate of postoperative complications. We wonder if complications can be anticipated and correlated to patient demographics, lifestyle, fracture or surgery related factors. We retrospectively reviewed all medical reports of patients who underwent ankle fracture surgery between 2013 and 2017. We focused our risks factors analysis on 5 common complications : poor wound healing, surgical site infection, malunion, nonunion and chronic pain. Multivariate logistic regression was performed to analyze significant risk factors for these complications. We identified 433 patients. Complications were present in 26% of the cases. The most frequent complication was poor wound healing (10%) associated with deep surgical site infection in 6%. Malunion was found in 7% and nonunion in 3%. Seven percent of patients suffered from chronic pain. More severe fractures happened to be a risk factor for poor wound healing (p = 0,032) and malunion (p < 0,001). Open fractures had respectively 6 to 9 times more mal- (p = 0,012) and nonunion (p = 0,018). Overweight patients with alcohol abuse were doubling their chances of cutaneous (p = 0,030) and infectious (p = 0,040) complications, and tripling their risks of ankle fracture nonunion (p = 0,003). Female and patients operated at night (p = 0,045) seemed to be more at risk to develop chronic pain (p = 0,028). Complications of ankle fracture treatment are frequent and their risks increases with more complex and open fractures. This study brings new evidence concerning the combined effect of overweight and alcohol abuse on poor wound healing, surgical site infection and non-union.

Can infection be predicted after intramedullary nailing of tibial shaft fractures?

Despite the progress in tibial fracture care, some patients contract infection following intramedullary nailing. We analyzed which risk factors could predict infection in 171 tibial fractures. The independent variables included age, gender, body mass index, and comorbidities, along with external factors of fracture pattern, nailing settings, and treatment processing time. A multiple logistic regression was used to identify infection risk factors. The risk of infection significantly increased according to the open grading, the fractures' classification, time until antibiotic administration, and time until nailing. Gustilo type I fractures presented a higher rate of infection than expected, explained by a longer delay before surgery. The probabilistic equation allows infection prediction with high sensitivity and specificity. In total, we showed that no antibiotics' prescription in emergency service and a transverse fracture pattern were predictors of infection. An infection risk score can be computed, aiding surgeons in decision making. Outcomes could improve keeping these observations in mind. Level of evidence: Retrospective cohort study. Level iii.

Surgical treatment of lateral ankle instability. Does allograft tendon have a better functional result?

Surgical treatment of lateral ankle instability can be performed with or without allograft. We compared these two technical options referring to patients' functional, radiological and ultrasound data. Forty patients were surgically treated for lateral pain- ful instability of the ankle. Twenty patients underwent ligamentoplasty using the Broström-Gould technique and twenty underwent a ligamentoplasty by allograft tendon. Patients were matched in age and gender. The assessment was done at 2.5 years postoperatively by functional scores (Olerud & Molander, and Foot & Ankle Outcome), dynamic x-rays (focused on varus and anterior drawer stress tests) and ultrasound examination (focused on anterior talo-fibular and calcaneo-fibular ligaments). No significant difference was found between the two techniques for all scores. Functional scores were more than 75% and the complication rate was low (<10%). Regarding the surgical technique, the tendon allograft could not prove to be more beneficial.

Assessment of Resection Margins in Bone Tumor Surgery.

Limb salvage surgery is now the preferred procedure for bone tumor surgery. To decrease the risk of local recurrence, it is crucial to obtain adequate resection margins. The obtained margins must be evaluated postoperatively because they influence what treatment is given subsequently when margins are not adequate (e.g., surgical revision and radiotherapy). The study aims to evaluate margin assessment of tumor specimen by MRI compared to conventional histology (to establish the viability of using MRI) and assess the accuracy of a patient-specific instrument when narrow margins were aimed. The resection margins in 12 consecutive patients that were operated on for bone tumor resection were prospectively analyzed using three methods: MRI of the resection specimen, macroscopic evaluation of specimen slices, and microscopic pathological evaluation. The assessments were qualitative (R0, R1, and R2) and quantitative (distance in mm). MRI, macroscopic, and microscopic margins generated similar results for both the qualitative (all resections were R0) and quantitative assessments. The median error in safe margins was 2 mm with a surgical guide (PSI) and 5 mm without a surgical guide. Local recurrences were not detected after a mean follow-up period of 3.7 years (range, 2.1-5 years); however, four patients died during the study. In conclusion, MRI is a valuable tool for assessing safe margins. When specimens are not available for pathological assessment (e.g., extracorporeally irradiated autograft or autoclaved autograft), MRI could be used to evaluate margins. In particular, when tumor volume is high, MRI could also help to focus the pathological examination on areas of concern.

Predictors of mechanical complications after intramedullary nailing of tibial fractures.

INTRODUCTION: Intramedullary (IM) nailing is the gold standard treatment for tibial shaft fractures, but can be associated with various mechanical complications, including delayed union. HYPOTHESIS: We believe that complications do not occur randomly, but in certain conditions that contribute to their development. Risk factors likely to predict delayed union can be identified to support prevention. MATERIALS AND METHODS: A cohort of 171 fractures treated by IM nailing between 2005 and 2015 was reviewed retrospectively. Independent variables included intrinsic, patient-related factors and extrinsic factors such as those related to the fracture or surgery. A multiple logistic regression model was used to determine which factors can predict each type of complication. RESULTS: Delayed union occurred in 22.8% of patients. Smoking and high-energy trauma were risk factors. Hardware breakage was significantly reduced (p<0.05) when the nail diameter was greater than 10mm. A nail diameter/reamer diameter ratio outside the recommended limits (0.80-0.99) was more likely to be associated with screw failure. Diabetes is a risk factor for hardware migration, which itself is associated with other complications. DISCUSSION: Nonunion is the most common complication after IM nailing of tibial shaft fractures. Smoking cessation after a fracture is necessary in our opinion, even if the literature is ambivalent on this aspect and stopping to smoke once the fracture occurs may not be sufficient to prevent a poor outcome. Use of a nail diameter/reamer diameter between 0.80 and 0.99 favors union and prevents hardware breakage. Hardware migration in a diabetic patient may be a warning sign of other types of complications. LEVEL OF EVIDENCE: Retrospective cohort study. Level IV.

Gait abnormalities following slipped capital femoral epiphysis treated with in situ fixation.

BACKGROUND: Slipped capital femoral epiphysis (SCFE) is a common disorder in adolescent for which no consensus exists regarding management. The aim of the present study was to analyze gait modifications following SCFE treated with in situ fixation (ISF) and to relate it to radiologic stage. RESEARCH QUESTION: To verify if gait biomechanics are impaired in patients with SCFE and to try to determine a degree of slippage from which gait modifications would appear. METHODS: We evaluated 16 patients treated by ISF for SCFE with slippage ranging from 11° to 61°. Gait variables were compared to normal population according to age and walking speed and were normalized in Z-scores. RESULTS: Spatiotemporal parameters, mechanical and energetic variables were inferior to |1.5| Z-scores and considered as normal. Kinematics showed increase of pelvic tilt and hip adduction. Kinetic variables showed modifications with increased hip extension moment. There was also a strong increase in power of hip extensor. Hip extension moment and power of hip extensors were significantly correlated to radiologic stage. Analysis of ROC curves showed a cut-off value of slippage about 25°-30° affecting kinematics of pelvis and hip and kinetic variables. CONCLUSION: The gait variables were close to normal values. Main modifications were observed in kinematic and kinetic data with a significant increase in extension moment and power generated at the operated hip. This could participate to long-term joint degradation observed in SCFE, even in mild slips. The clinical message is to control regularly SCFE with initial slippage greater than >25-30° to allow for early diagnosis of premature hip osteoarthritis.

Rasch analysis of the Forgotten Joint Score in patients undergoing knee arthroplasty.

PURPOSE: The purpose of this study was to test the hypothesis that the "Forgotten Joint Score" (FJS-12) is a unidimensional interval-level scale. Unidimensionality refers to measuring a single attribute, i.e., the single ability to forget the arthroplasty. If this property is not verified, the interpretation of the score can be confusing. Unidimensionality is an essential prerequisite of construct validity and required if FJS-12 response data are to be validly summated into a single score. Interval-level dimension is an essential prerequisite of the parametric statistics. Rasch analysis was used to test our study hypothesis. METHODS: The FJS-12 questionnaire was validated in 248 unilateral knee arthroplasty patients. Successive analyses were used to select items with good psychometric qualities to constitute the new "FJS". The external validity was assessed with the KUJALA questionnaire. RESULTS: Quantity of relevant items was greater than 50%. Of the 12 original items, nine showed disturbed thresholds, indicating that patients were unable to discriminate among the five levels for these items. The data set was reanalyzed using a four-level scale. The new analysis indicated that the internal consistency was good (r = 0.84). Three items did not fit with the model and they were removed. The nine items of the final scale defined a unidimensional and linear measure of the forgotten joint, and showed a continuous progression in their difficulty. The perception of difficulty was group-independent. The correlation coefficient was moderate between FJS and KUJALA score (r = 0.4). CONCLUSIONS: This new and items reduced FJS can be used in clinical practice with good psychometric qualities. It provides a reliable tool to follow up patient's evolution and document changes related to knee arthroplasty. This valid FJS is needed in evaluating patients' assessment, one indicator of quality of care. LEVEL OF EVIDENCE: III-Therapeutic.

Effect of Radial Nerve Release on Lateral Epicondylitis Outcomes: A Prospective, Randomized, Double-Blinded Trial.

PURPOSE: The purpose of our study was to examine the result of lateral epicondylitis surgery with and without posterior interosseous nerve release. METHODS: We conducted a prospective, randomized, double-blind single-center clinical trial in 54 patients treated surgically for lateral epicondylitis, without any EMG or imaging sign of compression of the posterior interosseous nerve at the arcade of Frohse. The patients were equally divided into intervention (supplemental radial nerve release) and control groups (no radial nerve release). Clinical symptoms and disability related to the upper extremity were assessed by a blinded assessor prior to surgery, using both the Quick Disabilities of the Arm, Shoulder, and hand (QuickDASH) and Mayo Elbow Performance Score (MEPS) and again at 1-, 3-, and 6-month intervals after surgery. RESULTS: Significant improvement was observed in both groups from the first month after surgery and for the whole evaluation period for both the MEPS and the QuickDASH scores. CONCLUSIONS: Radial nerve release, in association with surgical treatment for lateral epicondylitis, was not associated with greater improvement. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic I.

Gait in patients with adolescent idiopathic scoliosis. Effect of surgery at 10 years of follow-up.

PURPOSE: To assess radiological and gait biomechanical changes before, at one and 10 years after surgery in AIS patients. METHODS: This clinical prospective study included fifteen adult women (mean[SD] age: 26 [1] years) diagnosed with thoraco-lumbar/lumbar AIS and operated 10 years ago. Clinical, radiological and gait variables, including kinematics, electromyography (EMG), mechanics and energetics were compared between presurgery (S0), 1 year (S1) and 10 years (S2) postsurgery period using a one way repeated measure ANOVA. RESULTS: The Cobb angle of the scoliosis curve was reduced by 55% at 1 year postsugery but only by 37% at 10 years postsurgery suggesting a loss of 32% over time. Frontal plumb line C7-S1 distance was significantly improved by surgery (-44%) and remained stable at 10 years postsurgery. Lower limb kinematics was not affected by the surgery at long term. Excessive bilateral activation of lombo-pelvic muscles, observed before surgery, decreased significantly at S1 and S2 period. Mechanical energy increased significantly between S0, S1 and S2 session, without any change for the energetic variables. CONCLUSIONS: Between 1 and 10 years post-surgery, thoraco-lumbar/lumbar AIS women showed a few decompensation of the curve without any change of the improved frontal body balance. Lower limbs and pelvic motion, during gait, was not affected by the surgery. But presurgical excessive EMG activity of the lumbo-pelvic muscle and reduced mechanical energy produced to walk get similar to normal patterns. Only the oxygen consumption remained excessive probably due to physical deconditioning or postural instability.

Assessment of upper limb spasticity in stroke patients using the robotic device REAplan.

OBJECTIVE:  To assess the capacity of the robotic device REAplan to measure overall upper limb peak resistance force, as a reflection of upper limb spasticity. METHODS:  Twelve patients with chronic stroke presenting upper limb spasticity were recruited to the study. Patients underwent musculocutaneous motor nerve block to reduce the spasticity of elbow flexor muscles. Each patient was assessed before and after the motor nerve block. Overall the REAplan measured upper limb resistance force. The robot passively mobilized the patient's upper limb at various velocities (10, 20, 30, 40 and 50 cm/s) in a back-and-forth trajectory (30 cm). The peak resistance force was analysed for each forward movement. Ten movements were performed and averaged at each velocity condition. RESULTS: The overall upper limb resistance force increased proportionally to the mobilization velocity (p< 0.001). Resistance force decreased after the motor nerve block at 40 and 50 cm/s (p < 0.05). Overall upper limb resistance force results showed excellent correlation with the Modified Ashworth Scale for elbow flexor muscles, for each velocity condition equal or higher than 30 cm/s (ρ >0.6). CONCLUSION:  This study proposes a new, valid, reliable and sensitive protocol to quantify upper limb resistance force using the REAplan, as a reflection of upper limb spasticity.

Pedicle screw insertion accuracy in terms of breach and reposition using a new intraoperative cone beam computed tomography imaging technique and evaluation of the factors associated with these parameters of accuracy: a series of 695 screws.

PURPOSE: The goals of this study were to assess the accuracy of pedicle screw insertion using an intraoperative cone beam computed tomography (CBCT) system, and to analyze the factors potentially influencing this accuracy. METHODS: Six hundred and ninety-five pedicle screws were inserted in 118 patients between October 2013 and March 2016. Screw insertion was performed using 2D-fluoroscopy or CBCT-based navigation. Accuracy was assessed in terms of breach and reposition. All the intraoperative CBCT scans, done after screw insertion, were reviewed to assess the accuracy of screw placement using two established classification systems: Gertzbein and Heary. Generalized linear mixed models were used to model the odds (95% CI) for a screw to lead to a breach according to the independent variables. RESULTS: The breach rate was 11.7% using the Gertzbein classification and 15.4% using the Heary classification. Seventeen screws (2.4%) were repositioned intraoperatively. The only factor affecting statistically the odds to have a breach was the indication of surgery. The patients with non-degenerative disease had a significantly higher risk of breach than those with degenerative disease. CONCLUSION: Use of intraoperative CBCT as 2D-fluoroscopy or coupled with a navigation system for pedicle screw insertion is accurate in terms of breach occurrence and reposition. However, these rates depend on the classification or grading system used. Use of a navigation system does not decrease the risk of breach significantly. And the risk of breach is higher in non-degenerative conditions (trauma, scoliosis, infection, and malignancy disease) than in degenerative diseases.

Joint torque variability and repeatability during cyclic flexion-extension of the elbow.

BACKGROUND: Joint torques are generally of primary importance for clinicians to analyze the effect of a surgery and to obtain an indicator of functional capability to perform a motion. Given the current need to standardize the functional evaluation of the upper limb, the aim of this paper is to assess (1) the variability of the calculated maximal elbow joint torque during cyclic elbow flexion-extension movements and (2) participant test-retest repeatability in healthy young adults. Calculations were based on an existing non-invasive method including kinematic identification and inverse dynamics processes. METHODS: Twelve healthy young adults (male n = 6) performed 10 elbow flexion-extension movement carrying five different dumbbells (0, 1, 2, 3 and 4 kg) with several flexion-extension frequencies (½, (1)/3, » Hz) to evaluate peak elbow joint torques. RESULTS: Whatever the condition, the variability coefficient of trial peak torques remained under 4 %. Bland and Altman plot also showed good test-retest, whatever the frequency conditions for the 0, 1, 2, and 3 kg conditions. CONCLUSION: The good repeatability of the flexion-extension peak torques represents a key step to standardize the functional evaluation of the upper limb.

Nature of passive musculoarticular stiffness increase of ankle in female subjects with fibromyalgia syndrome.

The objective of this study was to assess the passive elastic and viscous stiffness components of ankle in young, middle-aged and old adult female fibromyalgia subjects and compare the results with age-matched healthy control subjects. The passive musculoarticular stiffness of the ankles of 60 fibromyalgia subjects and 52 controls was quantified by measuring the ankle resistance to imposed sinusoidal rotary displacements at nine different oscillation frequencies. For each frequency, the resulting torque response of the ankles was decomposed into elastic and viscous components of the total stiffness. The self-perceived stiffness intensity of the ankles was assessed in fibromyalgia subjects by means of a visual analogue scale. Two-way ANOVA test indicated a significant effect of fibromyalgia (P < 0.001) and age (P < 0.001) on elastic stiffness results and a significant effect of age (P < 0.001) on viscous stiffness results. Post hoc Holm-Sidak test indicated that younger and middle-aged fibromyalgia subjects had a significant elastic stiffness increase of more than two times that of controls (P = 0.038 and P < 0.001, respectively). Middle-aged fibromyalgia subjects had a significant viscous stiffness increase of 1.2 times that of controls (P = 0.038). No significant differences in stiffness were observed between older fibromyalgia subjects and controls. In conclusion, the self-perceived stiffness increase of ankle reported by younger and middle-aged fibromyalgia subjects is due to changes in elastic and/or viscous musculoarticular structures around the ankle. The absence of changes in older fibromyalgia subjects is probably related to the ageing process of controls.