Noël L W Keijsers

Noël L W Keijsers
Sint Maartenskliniek · Department for Scientific Research

About

115
Publications
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Introduction

Publications

Publications (115)
Poster
Full-text available
BACKGROUND: End-stage osteoarthritis (OA) of the knee is characterized by pain and joint stiffness. When these symptoms substantially limit daily-life activities, total knee replacement (TKR) is considered. The decision towards TKR strongly hinges on subjective patient report of the extent of daily-life limitation, which may poorly reflect actual p...
Poster
Full-text available
Introduction: Restoration of physical functioning is a major aim of total joint arthroplasty, which is typically evaluated by subjective patient-reported outcome measures (PROMs). In this study, we aimed to investigate objective recovery of gait - including turning, upper body motion, and gait automaticity - after total knee (TKA) and hip arthropla...
Article
Full-text available
Objective: Toe walking due to progressive shortening of the calf muscles is common in people with hereditary spastic paraplegia. Achilles tendon lengthening is a treatment option, but clinicians are often hesitant to use this procedure, as it may result in weakening of the calf muscles and, subsequently, in reduced ankle power and knee instability...
Article
Full-text available
Gait impairments in people with hereditary motor and sensory neuropathy (also known as Charcot-Marie-Tooth disease) are the combined result of ankle-foot deformities, muscle weakness, and somatosensory impairments. People with hereditary neuropathies often experience pain and difficulties when walking, especially barefoot. They also trip and fall f...
Conference Paper
Full-text available
Background: Recent research has shown that leg dominance has an impact on gait and that this impact is significant enough that a leg dominance scores are worth developing. However, it remains unclear how leg dominance impacts plantar pressure measurements. Some studies assume that measurements from opposing feet are identical while others assume th...
Article
This study aims were twofold: (1) to evaluate the construct validity of the Repetitive Movement Test (RMT) a novel test developed for Wheelchair Rugby classification which evaluates arm coordination impairment at five joints – shoulder, elbow, forearm, wrist and fingers – and (2), pending sufficiently positive results, propose objective minimum imp...
Article
Background Since adequate sleep is essential for optimal inpatient rehabilitation, there is an increased interest in sleep assessment. Unobtrusive, contactless, portable bed sensors show great potential for objective sleep analysis. Objective The aim of this study was to investigate the feasibility of a bed sensor for continuous sleep monitoring o...
Article
Full-text available
Previous research showed that an Inertial Measurement Unit (IMU) on the anterior side of the shank can accurately measure the Shank-to-Vertical Angle (SVA), which is a clinically-used parameter to guide tuning of ankle-foot orthoses (AFOs). However, in this context it is specifically important that differences in the SVA are detected during the tun...
Article
Diagnosing foot complaints using plantar pressure videos is complicated by the presence of confounding factors (e.g. age, weight). Outlier detection could help with diagnosis, but these confounding factors result in data that is not independent and identically distributed (IID) with respect to a specific patient. To address this non-IID problem, we...
Preprint
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Background: Exoskeleton use by people with complete spinal cord injury (SCI) in daily life is still a challenge. To optimize its daily life use, a better understanding of the purpose of use and the accompanying improvements are needed. The perspective of experienced exoskeleton users provides an important contribution to the improvement of future e...
Article
Full-text available
The distance one can walk at a time could be considered an important functional outcome in people with a lower limb amputation. In clinical practice, walking distance in daily life is based on self-report (SIGAM mobility grade (Special Interest Group in Amputee Medicine)), which is known to overestimate physical activity. The aim of this study was...
Article
Full-text available
Introduction: Overuse injuries often start with a musculoskeletal complaint, which can progress over time to an injury. Little or no information is known about the development and severity of overuse injuries in military recruits. This study describes the musculoskeletal complaints in Dutch military recruits during their basic training and examine...
Article
Full-text available
A consequence of a complete spinal cord injury (SCI) is the loss of gait capacity. Wearable exoskeletons for the lower extremity enable household and community ambulation in people with SCI. This study assessed the amount, purpose, and location of exoskeleton use in the home and community environment, without any restrictions. The number of steps t...
Preprint
BACKGROUND Since adequate sleep is essential for optimal inpatient rehabilitation, there is an increased interest in sleep assessment. Unobtrusive, contactless, portable bed sensors show great potential for objective sleep analysis. OBJECTIVE The aim of this study was to investigate the feasibility of a bed sensor for continuous sleep monitoring o...
Poster
Full-text available
An inertial measurement unit (IMU) seems to be a responsive measurement tool to assess the shank to vertical angle during walking (SVA). To be clinically applicable for tuning ankle foot orthosis (AFOs), the accuracy should be improved.
Article
Background: The aetiology of chronic therapy resistant plantar fasciitis (CTRPF) is multifactorial with more focus in recent times on the gastroc-soleus complex. This study evaluates the effect of lengthening the gastrocnemius muscle in CTRPF. Methods: All patients with CRTPF complaints for at least one year underwent the same standard conservative...
Article
Full-text available
The Shank-to-Vertical Angle (SVA) is a commonly used parameter to describe orthotic alignment. 3D gait analysis (3DGA) or 2D video analysis are usually used to assess the SVA, but are not always feasible in clinical practice. As an alternative, an Inertial Measurement Unit (IMU) attached and aligned to the shank might be used. This study aimed to i...
Article
Full-text available
Recovery of the walking function is one of the most common rehabilitation goals of neurological patients. Sufficient and adequate sleep is a prerequisite for recovery or training. To objectively monitor patients’ progress, a combination of different sensors measuring continuously over time is needed. A sensor-based technological platform offers pos...
Article
Full-text available
Background: In infants with indications of upper cervical dysfunction, the Flexion-Rotation-Test and Lateral-Flexion-Test are used to indicate reduced upper cervical range-of-motion (ROM). In infants, the inter-rater reliability of these tests is unknown. Objective: To assess the inter-rater reliability of subjectively and objectively measured ROM...
Article
Full-text available
Quantitative analyses of plantar pressure images typically occur at the group level and under the assumption that individuals within each group display homogeneous pressure patterns. When this assumption does not hold, a personalized analysis technique is required. Yet, existing personalized plantar pressure analysis techniques work at the image le...
Article
Powered robotic exoskeletons are a promising solution to enable standing and walking in patients with spinal cord injury (SCI). Although training and walking with an exoskeleton in motor complete SCI patients is considered safe, the risks of unexpected (technical) adverse events and the risk of fractures are not fully understood. This article repor...
Article
Full-text available
Purpose of the article: Learning to use an exoskeleton is time consuming and diverse between users. Knowledge about trainability of exoskeleton skills is relevant for planning and expectation management. The objective was to assess predictors of exoskeleton skill performance during and after exoskeleton training. Materials and methods: Twenty-four...
Article
Background: Improvement of balance control is an important rehabilitation goal for patients with motor and sensory impairments. To quantify balance control during walking, various stability outcome measures have described differences between healthy controls and patient groups with balance problems. To be useful for the evaluation of interventions...
Article
Introduction: This study investigated the effect of operative claw toe correction with release of the metatarsophalangeal (MTP) joint, repositioning of the plantar fat pad and resection of the proximal interphalangeal joint on foot kinematics, plantar pressure distribution and Foot Function Index (FFI). Methods: Prospective experimental study wi...
Article
Full-text available
Background: Gait impairments are common and disabling in chronic stroke patients. Pes equinovarus deformity is one of the primary motor deficits underlying reduced gait capacity after stroke. It predisposes to stance-phase instability and subsequent ankle sprain or falls. This instability is most pronounced when walking barefoot. Tarsal fusion is...
Conference Paper
Full-text available
This study characterizes plantar pressure differences between hallux valgus patients and healthy controls using statistical parametric mapping (SPM). The plantar pressure differences are minimal which, combined with previous studies, suggest high variability in the plantar pressures of hallux valgus patients.
Poster
Full-text available
While dynamic plantar pressure measurements are commonly used for clinical evaluation of gait-related problems, computational analysis techniques for these datasets are few and far between. To address this issue, we introduce an open-access database of plantar pressure videos for researchers to develop algorithms around.
Article
Background: Although posterior spinal correction and fusion surgery (PSF) of adolescent idiopathic scoliosis (AIS) limits counter rotation between thorax and pelvis, the physical function, and more specifically gait of these patients is only slightly affected after PSF. Possibly, shoulders-thorax counter-rotation increases to compensate for the lo...
Article
Data reduction techniques are commonly applied to dynamic plantar pressure measurements, often prior to the measurement’s analysis. In performing these data reductions, information is discarded from the measurement before it can be evaluated, leading to unknown consequences. In this study, we aim to provide the first assessment of what impact data...
Article
Full-text available
Background: Wearable exoskeletons can be a powerful tool for the facilitation of ambulation of complete Spinal Cord Injury (SCI) subjects, which has several psychological and physical advantages. However, exoskeleton control is difficult for this group of users and requires a long period of training. People with SCI not only lack the motor control...
Article
Full-text available
Many patients with incomplete spinal cord injury (iSCI) have impaired gait and balance capacity, which may impact daily functioning. Reduced walking speed and impaired gait stability are considered important underlying factors for reduced daily functioning. With conventional therapy, patients are limited in training gait stability, but this can be...
Article
Previous gait analysis studies of patients with an ankle arthrodesis have reported increased motion in the adjacent joints. However, of similar importance are the forces that act on the ipsi- and contralateral joints and the effect of ankle arthrodesis with regard to balance control. The purpose of the present study was to determine the joint momen...
Article
Background: Pedobarography produces large sets of plantar pressure samples that are routinely subsampled (e.g. using regions of interest) or aggregated (e.g. center of pressure trajectories, peak pressure images) in order to simplify statistical analysis and provide intuitive clinical measures. Research question: We hypothesize that these data r...
Article
Background context: Adolescent idiopathic scoliosis (AIS) patients perform surprisingly well after spinal correction and fusion. It was previously hypothesized that, during gait, certain mechanisms compensate for the loss in spinal motion. Still, previous studies could not identify such compensatory mechanisms in the lower body. Purpose: This st...
Article
Full-text available
Importance Gait impairments are common in patients with chronic supratentorial upper motor neuron lesions and are a source of disability. Clinical management aimed at improving the gait pattern in these patients is generally perceived as a challenging task because many possible abnormalities may interact. Moreover, a multitude of treatment options...
Article
Full-text available
Purpose: To investigate the effects of posterior spinal fusion (PSF) and curve type on upper body movements in Adolescent Idiopathic Scoliosis (AIS) patients during gait. Methods: Twenty-four girls (12-18 years) with AIS underwent PSF. 3D-Gait-analyses were performed preoperatively, at 3 months and 1 year postoperatively. Mean position (0° repre...
Article
Trunk coordination is essential for many activities of daily living in wheelchair users. This study investigated whether Fitts' law is applicable to trunk movements in a sitting position. Fourteen healthy adults performed two series of 24 tasks of trunk flexion–extension movements in a sitting position. The results showed significant linear relatio...
Article
Full-text available
For safe application of exoskeletons in people with spinal cord injury at home or in the community, it is required to have completed an exoskeleton training in which users learn to perform basic and advanced skills. So far, a framework to test exoskeleton skills is lacking. The aim of this study was to develop and test the hierarchy and reliability...
Article
The authors regret to have included an incorrect panel of Fig. 1 to the manuscript. In Fig. 1, the bottom right panel (pelvis, transversal plane) has an incorrect colour setting. Line colour and line type should represent measurement time (pre-operative, 3 months post-operative, and 12 months post-operative) and walking speed (0.45, 1.35, and 2.22...
Article
The cover image, by V. C. Altmann et al., is based on the Original Article The impact of trunk impairment on performance-determining activities in wheelchair rugby, DOI: 10.1111/sms.12720. Photo Credit: V. C. Altmann and Miranda Dood.
Article
Background Despite impressive results of the pharmacological management of rheumatoid arthritis, still certain patients suffer from rheumatoid forefoot problems. Surgical treatment of these forefoot deformities can be an option. In literature no high-quality studies on this topic can be found. The goal of present study is to compare the results of...
Article
Background: Ankle arthrodesis provides satisfactory functional outcome based on basic daily activities, but information regarding more demanding tasks is limited. Also, studies reporting longer term survival and complication rates are sparse and concern small study populations. This study reports functional outcome with more focus on demanding tas...
Article
International Federations in Paralympic sport should develop evidence based classification, based on the relative strength of association between impairment and activities that determine sport specific performance. The purpose of the current study was to assess the relationship between trunk strength impairment and three activities that determine p...
Article
Introduction Previous studies show a limited alteration of gait at normal walking speed after spinal fusion surgery for adolescent idiopathic scoliosis (AIS), despite the presumed essential role of spinal mobility during gait. This study analyses how spinal fusion affects gait at more challenging walking speeds. More specifically, we investigated w...
Article
Objectives: Anterior Cruciate Ligament (ACL) deficiency may result in abnormal lower limb loading with increased foot pronation. This study evaluated spatiotemporal parameters and plantar pressure distribution during walking in participants with and without an ACL rupture. Design: Cross-sectional. Methods: Plantar pressure was measured in 42 u...
Article
Aims: The concept of 'classification' has, similar to many other diseases, been found to be fundamental in the field of diabetic medicine. In the current study, we aimed at determining efficacy measures of a recently published plantar pressure based classification system. Methods: Technical efficacy of the classification system was investigated...
Article
Background: Comparing the dynamic pedobarographic patterns of individuals is common practice in basic and applied research. However, this process is often time-consuming and complex, and commercially available software often lacks powerful visualization and interpretation tools. Methods: We propose a simple method for displaying pixel-level pedo...
Article
Functional outcomes after surgery for low-grade isthmic spondylolisthesis(LGIS) is reported limitedly for combined posterior and anterior approach procedures. Imbalances in the sagittal alignment of spine and pelvis are increasingly seen as the reason for the development and progression of LGIS. Aims of this study: 1) functional outcome, 2) the eff...
Article
Study aim: To investigate differences in the center of pressure (COP) during gait and single leg stance between subjects with persistent complaints (PC) and without persistent complaints (NPC) after a lateral ankle sprain. Methods: 44 patients who consulted the general practitioner, 6-12 months prior to inclusion, with a lateral ankle sprain wer...
Article
Full-text available
Purpose In this prospective study, the changes in kinetics and kinematics of gait and clinical outcomes after a varus osteotomy (tibial, femoral or double osteotomy) in patients with osteoarthritis (OA) of the knee and a valgus leg alignment were analysed and compared to healthy subjects. Methods Twelve patients and ten healthy controls were includ...
Article
Full-text available
Background: It is unclear whether proximal interphalangeal joint (PIPJ) resection or fusion leads to superior clinical outcome in patients undergoing hammertoe surgery. The purpose of this study was to prospectively evaluate a series of patients undergoing this surgery. Methods: Patients with one or more toes with rigid PIP flexion deformity wer...
Article
Full-text available
Locomotor malfunction represents a major problem in some neurological disorders like stroke and spinal cord injury. Robot-assisted walking devices have been used during rehabilitation of patients with these ailments for regaining and improving walking ability. Previous studies showed the advantage of brain-computer interface (BCI) based robot-assis...
Data
Gait cycles were determined according to the right heel strike (red dots) using the accelerometer’s data from the right (blue continue line) leg. The left leg’s accelerometer data is as well illustrated (black dotted line) for comparisons. (TIF)
Data
Power density analysis of EMG artifacts in healthy volunteers. a. Spectral density analysis over all electrodes for active and passive walking and the baseline before passive and active walking conditions. b. Topographic distribution of event related desynchronization (ERD) and synchronization (ERS) in the mu (8–12 Hz), beta (15-30Hz) and low gamma...
Article
Objective: To determine the validity of the Trunk Impairment Classification system (TIC) with four possible scores (0, most impaired, 0.5, 1.0, 1.5, least impaired) in relation to objective instrumented measures of impairment. Design: TIC scores were compared to objective measures of neuromusculoskeletal trunk impairment in a cross sectional des...
Article
Background Patients with lateral ankle sprains represent a large group in general practice (GP) and one-third report persistent complaints, which include pain, instability or re-sprains. Objective To investigate differences in the centre of pressure (COP) during gait and single leg stance between subjects with persistent complaints (PC) and without...
Article
Background: Discrepancies observed between clinical findings and a weightbearing foot X-ray might be caused by a patients' positioning. This study's main objective was to determine the effect of a subjects' posture on the osseous relations of the foot. Methods: Anatomical markers were placed on the skin of the foot of 17 subjects. A plantar pres...
Article
Comparing plantar pressure measurements (PPM) of a patient following an intervention or between a reference group and a patient-group is common practice in clinical gait analysis. However, this process is often time consuming and complex, and commercially available software often lacks powerful visualization and interpretation tools. In this paper,...
Article
Full-text available
Objectives: To determine patient independency, health-related and disease-specific quality of life (QOL), gait pattern, and muscle strength in patients after salvage arthroplasty for failed internal fixation of a femoral neck fracture. Design: Secondary cohort study to a randomized controlled trial. Setting: Multicenter trial in the Netherland...