Towards the definition of a patient-specific rehabilitation program for TKA: A new MRI-based approach for the easy volumetric analysis of thigh muscles.

After Total Knee Arthroplasty (TKA), a global post-operative rehabilitation programme is commonly performed. However, this current program is not always adapted to every patient and it could be improved by deeply reinforcing weaker thigh muscles. To do this, a muscle volume estimation coupled with force evaluation is required to therefore adapt the rehabilitation as a specific patient exercise plan. In this paper, we presented an MRI protocol allowing the acquisition of the whole thigh as well as a semi-automated pipeline to segment two main groups of thigh muscles, i.e., the quadriceps femoris and the hamstrings muscles. The pipeline is based on a few cross-sections manually labelled and a 3D-spline interpolation using directed graphs corresponding points. The seven muscles of ten thighs (70 muscles in total) were segmented and reconstructed in 3D. To assess this pipeline, three types of metrics (volumetric similarity, surface distance, and classical measures) were employed. Furthermore, the inter-muscle overlapping was calculated as an additional metric. The results showed mean DICE was 99.6% (±0.1), Hausdorff Distance was 4.9 mm (±1.8) and Absolute Volume Difference was 2.97 cm3 (±1.94) in comparison to the manual ground truth. The average overlap was 2.05% (±0.54).Clinical Relevance- The proposed segmentation method is fast, accurate and possible to integrate in the clinical workflow of TKA.

European consensus on the concepts and measurement of the pathophysiological neuromuscular responses to passive muscle stretch.

BACKGROUND AND PURPOSE: To support clinical decision-making in central neurological disorders, a physical examination is used to assess responses to passive muscle stretch. However, what exactly is being assessed is expressed and interpreted in different ways. A clear diagnostic framework is lacking. Therefore, the aim was to arrive at unambiguous terminology about the concepts and measurement around pathophysiological neuromuscular response to passive muscle stretch. METHODS: During two consensus meetings, 37 experts from 12 European countries filled online questionnaires based on a Delphi approach, followed by plenary discussion after rounds. Consensus was reached for agreement ≥75%. RESULTS: The term hyper-resistance should be used to describe the phenomenon of impaired neuromuscular response during passive stretch, instead of for example 'spasticity' or 'hypertonia'. From there, it is essential to distinguish non-neural (tissue-related) from neural (central nervous system related) contributions to hyper-resistance. Tissue contributions are elasticity, viscosity and muscle shortening. Neural contributions are velocity dependent stretch hyperreflexia and non-velocity dependent involuntary background activation. The term 'spasticity' should only be used next to stretch hyperreflexia, and 'stiffness' next to passive tissue contributions. When joint angle, moment and electromyography are recorded, components of hyper-resistance within the framework can be quantitatively assessed. CONCLUSIONS: A conceptual framework of pathophysiological responses to passive muscle stretch is defined. This framework can be used in clinical assessment of hyper-resistance and will improve communication between clinicians. Components within the framework are defined by objective parameters from instrumented assessment. These parameters need experimental validation in order to develop treatment algorithms based on the aetiology of the clinical phenomena.

Quantitative study of knee joint surface configurations using a morpho-functional approach.

Several models exist in the literature to describe knee kinematics. In this paper we propose a morpho-functional approach based on the determination of a simulated kinematics of flexion/extension from a unique CT scan acquisition. We will compare this kinematics to the real one obtained from experiments on one cadaver. In parallel, we have developed quantitative tools for the assessment of the motion. As the computation of these tools depends on the bone morphology, they can describe the state of the joint, which is not classical in the literature. Both tools follow the evolution of the distances between two bones during motion. They are called the Figure of Articular Coherence and the Index of Articular Coherence. In order to verify the relevance of these tools, we have tested them to compare different surgeries of Anterior Cruciate Ligament (ACL) reconstruction.

A survey of medical and paramedical involvement in children with cerebral palsy in Britanny: preliminary results.

AIM: To describe the amount of medical and paramedical involvement in a sample of Breton children with cerebral palsy as a function of the Gross Motor Function Classification System (GMFCS). MATERIALS AND METHODS: This is a transversal descriptive study. All children with cerebral palsy in Brittany were eligible. Parents who accepted to participate were asked to fill in a questionnaire regarding medical and paramedical involvement with their child. RESULTS: One hundred and thirty-three parents participated. 40.6% of the children were level I on the GMFCS, 20.3% II, 12.03% III, 13.53% IV and 13.53% were level V. Thirty-nine percent of the children took at least one medication (of which 43% were antiepileptic drugs). 33.1% of the children had received at least one injection of botulinum toxin within the year. Forty-four percent used a mobility aid. Eighty-five percent of the children had at least one orthotic device, most often a night ankle-foot orthosis. The median number of rehabilitation sessions per week was 3.85 [0.5-11.5]. The frequency and type of sessions were mostly related to the GMFCS level. CONCLUSION: This study reports high levels of medical and paramedical involvement. Studies must attempt to define optimal practice.

ANSO study: evaluation in an indoor environment of a mobile assistance robotic grasping arm.

OBJECTIVE: To evaluate the reliability and functional acceptability of the ''Synthetic Autonomous Majordomo'' (SAM) robotic aid system (a mobile Neobotix base equipped with a semi-automatic vision interface and a Manus robotic arm). MATERIALS AND METHODS: An open, multicentre, controlled study. We included 29 tetraplegic patients (23 patients with spinal cord injuries, 3 with locked-in syndrome and 4 with other disorders; mean SD age: 37.83 13.3) and 34 control participants (mean SD age: 32.44 11.2). The reliability of the user interface was evaluated in three multi-step scenarios: selection of the room in which the object to be retrieved was located (in the presence or absence of visual control by the user), selection of the object to be retrieved, the grasping of the object itself and the robot's return to the user with the object. A questionnaire was used to assess the robot's user acceptability. RESULTS: The SAM system was stable and reliable: both patients and control participants experienced few failures when completing the various stages of the scenarios. The graphic interface was effective for selecting and grasping the object ­ even in the absence of visual control. Users and carers were generally satisfied with SAM, although only a quarter of patients said that they would consider using the robot in their activities of daily living.

Physical and rehabilitation medicine (PRM) care pathways: adults with severe traumatic brain injury.

This document is part of a series of guidelines documents designed by the French Physical and Rehabilitation Medicine Society (SOFMER) and the French Federation of PRM (FEDMER). These reference documents focus on a particular pathology (here patients with severe TBI). They describe for each given pathology patients' clinical and social needs, PRM care objectives and necessary human and material resources of the pathology-dedicated pathway. 'Care pathways in PRM' is therefore a short document designed to enable readers (physician, decision-maker, administrator, lawyer, finance manager) to have a global understanding of available therapeutic care structures, organization and economic needs for patients' optimal care and follow-up. After a severe traumatic brain injury, patients might be divided into three categories according to impairment's severity, to early outcomes in the intensive care unit and to functional prognosis. Each category is considered in line with six identical parameters used in the International Classification of Functioning, Disability and Health (World Health Organization), focusing thereafter on personal and environmental factors liable to affect the patients' needs.

Unstable gait due to spasticity of the rectus femoris: gait analysis and motor nerve block.

We present the case of a 54 year-old man presenting with a right Brown-Séquard plus syndrome (BSPS) after a traumatic cervical spinal cord injury. After being operated on with selective tibial neurotomy and triceps surae lengthening because of a right spastic equinus foot, he developed a gait disorder at high speed. The patient complained about an instability of the right knee. Observational gait analysis exhibited an oscillating, flexion/extension motion of the right knee during stance, which was confirmed by gait analysis. Dynamic electromyographic recordings exhibited a clonus of the right rectus femoris (RF) during stance. The spastic activity of the RF and the abnormal knee motion totally reversed after a motor nerve block of the RF, as well as after botulinum toxin type A injection into the RF. We emphasize that complex, spastic gait disorders can benefit from a comprehensive assessment including gait analysis and nerve blocks.

Robust local estimation in anisotropic diffusion process.

In this work we propose to use an anisotropic diffusion process using robust statistics. We show that smoothing, while preserving edges, helps the segmentation of upper limb bones (shoulder) in MRI data bases. The anisotropic diffusion equation is mainly controlled using an automatic edge stopping function based on Tukey's biweight function, which depends on the values of gradients pixels. These values are divided into two classes: high gradients for pixels belonging to edges or noisy pixels, low ones otherwise. This process also depends on a threshold gradient parameter which splits both former classes. So a robust local estimation method is proposed to better eliminate the noise in the image while preserving edges. Firstly, the efficiency of the model in the noise reduction is quantified using an entropy criterion on synthetic data with different noise levels to evaluate the smoothing of the regions. Secondly, we use the Pratt's Figure of Merit (FOM) method to evaluate edges preservation. Eventually, a qualitative edge evaluation is given on a MRI volume of the shoulder joint.

Effectiveness of nitrous oxide and analgesic cream (lidocaine and prilocaine) for prevention of pain during intramuscular botulinum toxin injections in children.

AIMS: To evaluate the effectiveness of an analgesic protocol with nitrous oxide and anaesthetic cream (lidocaine and prilocaine, EMLA) for children undergoing botulinum toxin injections. PATIENTS AND METHODS: Prospective study including 51 injection sessions, 34 children with a mean age of 5.94 (range 2-15) and 209 injected muscles. Pain was evaluated with the Children's Hospital of Eastern Ontario Pain Scale (CHEOPS), the Visual Analogue Scale (VAS) and the Face Pain Scale (FPS) for the children and with a VAS for the parents. RESULTS: CHEOPS score for the 51 sessions was 8.50 (S.D. 3.56). Forty-nine percent of scores were above the therapeutic threshold of 9; 25% of the children evaluated the pain above the therapeutic threshold of 3; 44.74% of the parents' estimations exceeded 3. No correlation was found between age, weight, number of injected muscle and CHEOPS score. CONCLUSION: The association of MEOPA and anaesthetic cream is only effective for 50% of children. This is much lower than treatments for other types of acute induced pain in children. Botulinum toxin injections and cerebral palsy children present certain specificities which require improvements in this analgesic protocol.

Shoulder motion analysis using simultaneous skin shape registration.

A new non-invasive approach is proposed to study joint motions. It is based on dynamic tracking of the skin shape. A robust simultaneous registration algorithm (Iterative Median Closest Point) is used to follow the evolving shape and compute the rigid motion of the underlying bone structures. This new method relies on the differentiation of the rigid and elastic parts of the shape motion. A skin marker network is tracked by a set of infrared cameras. Unlike usual techniques, the algorithm tracks the instantaneous polyhedral shape embedding this network. This innovating approach is expected to minimize bias effect of skin sweeps and give some new information about the underlying soft tissue activities. Current application addresses the motion of the shoulder complex (humerus, clavicle and scapula). It is compared with two marker-based methods published in the literature. Preliminary results show significant differences between these three approaches. The new approach measurements give rise to greater rotations.