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Fulltext The assessment of immediate post-operative scoliosis correction using pedicle screw system by utilising the fulcrum bending technique

Chan CY, Kwan MK, Saravanan S, Saw LB, Deepak AS

Med J Malaysia, 2007 Mar;62(1):33-5.
PMID: 17682567 MyJurnal

Assessment of the curve flexibility is a crucial step in a surgeon's pre-operative planning for scoliosis surgery. Many techniques have been described. These include traction films, supine side bending films, push prone techniques, traction under general anaesthesia as well as fulcrum bending film. In this study, we studied the pre- and immediate post-operative radiographs of twenty eight adolescent idiopathic scoliosis (AIS) patients who were corrected using pedicle screw systems between January 2004 and August 2006. There were twenty two females and six male patients. The mean age of the patients were 17.5 years with a range of 12 to 38 years. Skeletal maturity of the patients was assessed by Risser's score. The majority was Risser 4 (15 cases, 53.6%). Based on King and Moe's classification, the most common curve was type 3 curve (15 cases, 53.6%). Among the twenty eight patients, twenty three patients underwent only posterior correction, while 5 patients underwent additional anterior release surgery. The mean pre-operative Cobb's angle for the posterior surgery group was 65.5 +/- 13.9 degrees and the mean post-operative Cobb's angle was 32.9 +/- 12.6 degrees. There was no difference between the mean correction estimated by fulcrum bending films (Fulcrum Flexibility) and the post- operative Correction Rate figures (44.2% vs. 49.9%). The mean Fulcrum Bending Correction Index (FBCI) in this group of patients is 112.8%. In the group of patients who underwent additional anterior release, their curves were noted to be larger and less flexible with the mean pre-operative Cobb's angle and Fulcrum Flexibility of 90.4 degrees +/- 9.3 degrees and 23.4% respectively. The Fulcrum Bending Correction Index (FBCI) for this group of patients was significantly higher than the posterior surgery group: i.e. 164.0% vs 112.8%. Thus, anterior release does help to improve the correction significantly. The fulcrum bending films give good pre-operative estimation of the amount of correction to be expected post-operatively. The fulcrum bending films can help to identify the curve types which might require anterior release in order to improve the scoliosis correction. Using the Fulcrum Bending Correction Index (FBCI) will also enable surgeons to quantify more accurately the amount of correction achieved by taking into account the inherent flexibility of the spine.

Matched MeSH terms: Range of Motion, Articular/physiology*
Fulltext Dynamic traction and passive mobilization for the rehabilitation of zone II flexor tendon injuries: a modified regime

Chai SC, Wong CW

Med J Malaysia, 2005 Jul;60 Suppl C:59-65.
PMID: 16381286

This retrospective study aims to evaluate the effectiveness of the modified regime for rehabilitation of Zone II flexor tendon injuries in Sibu Hospital. From January to December 2003, 8 patients with 15 injured digits were treated by using the combined method of dynamic traction and passive mobilization. According to Strickland's criteria, 14 (93.3%) digits achieved good to excellent outcomes and only 1 (6.7%) was rated as poor. No occurrence of tendon rupture was noted. The overall grip strength of the injured hand was 50.1% of the uninjured hand at 3 months after the repair. Our results compare favorably with the other published studies. We believed that this modified regime is as effective as other established regimes and suitable to be adopted in our setting. Further study with larger sample group will be required to consolidate our findings.

Matched MeSH terms: Motion Therapy, Continuous Passive*
Anthropometric and physiological profiles of sepak takraw players

Jawis MN, Singh R, Singh HJ, Yassin MN

Br J Sports Med, 2005 Nov;39(11):825-9; discussion 825-9.
PMID: 16244191

OBJECTIVES: Anthropometric and physiological profiles of national sepak takraw players were determined.
METHODS: Thirty nine players, specialising in the three playing positions (tekong/server, feeder, and killer/spiker) were divided into three age categories of under 15 (U15), under 18 (U18), and under 23 (U23) years of age. Height, weight, percent body fat (%bf), maximum oxygen consumption (Vo(2max)), range of motion (ROM), back and leg strength, and heart rate, for the estimation of oxygen consumption during matches, were recorded. Statistical analysis was performed using one way ANOVA for independent measurements and data are presented as mean+/-standard deviation.
RESULTS: The U23 players were significantly taller and heavier with significantly better ROM of the neck, trunk, and ankle joints and back and leg strength than the U15 players. No significant difference was found in %bf between the three age categories. Mean maximum heart rate during exercise was significantly higher in the U15 group when compared to the U18 and U23 groups (p<0.05). Mean Vo2max was similar between the three groups. Estimated oxygen consumption during matches was 69.1%, 68.5%, and 56.4% of Vo2max in the killer, tekong, and the feeder groups, respectively.
CONCLUSIONS: The mean height, body weight, and cardiopulmonary capacities of the players were within the Malaysian population norms, but were somewhat lower than those of players of other court games from other countries. %bf was also lower in these players. This study provides the much needed anthropometric and physiological data of sepak takraw players for further development of this sport.

Matched MeSH terms: Range of Motion, Articular/physiology
Assessing the Flexibility of the Proximal Thoracic Segments Above the "Potential Upper Instrumented Vertebra" Using the Cervical Supine Side Bending Radiographs in Lenke 1 and 2 Curves for Adolescent Idiopathic Scoliosis Patients

Chan CYW, Chiu CK, Kwan MK

Spine (Phila Pa 1976), 2016 Aug 15;41(16):E973-E980.
PMID: 26909833 DOI: 10.1097/BRS.0000000000001516

STUDY DESIGN: A prospective study.
OBJECTIVE: The aim of this study was to analyze the proximal thoracic (PT) flexibility and its compensatory ability above the "potential UIV."
SUMMARY OF BACKGROUND DATA: Shoulder and neck imbalance can be caused by overcorrection of the main thoracic (MT) curve due to inability of PT segment to compensate.
METHODS: Cervical supine side bending (CSB) radiographs of 100 Lenke 1 and 2 patients were studied. We further stratified Lenke 1 curves into Lenke 1-ve: PT side bending (PTSB) 80.0% of cases of the PT segment were unable to compensate at T3-T6. In Lenke 1+ve curves, 78.4% were unable to compensate at T6, followed by T5 (75.7%), T4 (73.0%), T3 (59.5%), T2 (27.0%), and T1 (21.6%). In Lenke 1-ve curves, 36.4% of cases were unable to compensate at T6, followed by T5 (45.5%), T4 (45.5%), T3 (30.3%), T2 (21.2%), and T1 (15.2%). A significant difference between Lenke 1-ve and Lenke 1+ve was observed from T3 to T6. The difference between Lenke 1+ve and Lenke 2 curves was significant only at T2.
CONCLUSION: The compensation ability and the flexibility of the PT segments of Lenke 1-ve and Lenke 1+ve curves were different. Lenke 1+ve curves demonstrated similar characteristics to Lenke 2 curves.
LEVEL OF EVIDENCE: 3.

Matched MeSH terms: Range of Motion, Articular/physiology*
Measurement of range of motions of L3-L4 healthy spine through offsetting reflective markers and in silico analysis of meshed model

Kosalishkwaran G, Parasuraman S, Singh DKJ, Natarajan E, Elamvazuthi I, George J

Med Biol Eng Comput, 2019 Oct;57(10):2305-2318.
PMID: 31444622 DOI: 10.1007/s11517-019-02026-6

Degenerative disc disease (DDD) is a common condition in elderly population that can be painful and can significantly affect individual's quality of life. Diagnosis of DDD allows prompt corrective actions but it is challenging due to the absence of any symptoms at early stages. In studying disc degeneration, measurement of the range of motion (RoM) and loads acting on the spine are crucial factors. However, direct measurement of RoM involves increased instrumentation and risk. In this paper, an innovative method is proposed for calculating RoM, emphasizing repeatability and reliability by considering the posterior thickness of the spine. This is achieved by offsetting the position of markers in relation to the actual vertebral loci. Three geometrically identical finite element models of L3-L4 are developed from a CT scan with different types of elements, and thereafter, mesh element-related metrics are provided for the assessment of the quality of models. The model with the best mesh quality is used for further analysis, where RoM are within ranges as reported in literature and in vivo experiment results. Various kinds of stresses acting on individual components including facet joints are analysed for normal and abnormal loading conditions. The results showed that the stresses in abnormal load conditions for all components including cortical (76.67 MPa), cancellous (69.18 MPa), annulus (6.30 MPa) and nucleus (0.343 MPa) are significantly greater as compared to normal loads (49.96 MPa, 44.2 MPa, 4.28 MPa and 0.23 MPa respectively). However, stress levels for both conditions are within safe limits (167-215 MPa for cortical, 46 MPa for the annulus and 3 MPa for facets). The results obtained could be used as a baseline motion and stresses of healthy subjects based on their respective lifestyles, which could benefit clinicians to suggest corrective actions for those affected by DDD.

Matched MeSH terms: Motion; Range of Motion, Articular
Changes in Muscle Activity in Response to Assistive Force during Isometric Elbow Flexion

Loh PY, Hayashi K, Nasir N, Muraki S

J Mot Behav, 2020;52(5):634-642.
PMID: 31571525 DOI: 10.1080/00222895.2019.1670128

This study investigated the muscle activity and force variability in response to perturbation of assistive force during isometric elbow flexion. Sixteen healthy right-handed young men (age: 22.0 ± 1.1 years; height: 171.9 ± 4.8 cm; weight 68.4 ± 11.2 kg) were recruited and the muscle activity of biceps brachii and triceps brachii were assessed using surface electromyography. Workload force and assistive force applied on isometric elbow flexion significantly affected the changes in both biceps and triceps muscle activities. A higher assistive force was shown to result in reduced biceps muscle activity compared to the unassisted period. In contrast, the efficiency of the assistive force acting on the biceps decreased as the assistive force increased. In general, the force variability of the biceps muscle remained approximately the same at lower workload force conditions than that at higher workload force conditions. In conclusion, higher assistive force may not yield a higher performance efficiency in human-assistive force interaction.

Matched MeSH terms: Range of Motion, Articular/physiology
Racial variations in knee joint laxity: A comparative study of the Jordanian Arab and Malay populations

Bashaireh KM, Yabroudi MA, Nawasreh ZH, Al-Zyoud SM, Bashir NB, Aleshawi AJ, et al.

Knee, 2020 Aug;27(4):1205-1211.
PMID: 32711883 DOI: 10.1016/j.knee.2020.05.003

BACKGROUND: A high incidence of joint laxity has been reported among Asians compared with Western populations, but clear differences between more specific ethnic populations have not been established. This study aimed to determine the average knee laxity in the Malaysian and Jordanian populations.
METHODS: Jordanian and Malaysian medical students from our institution were invited to participate in the study. General demographic data and factors affecting joint laxity were obtained from each participant using a printed questionnaire. Both knees were examined using the anterior drawer test while in 90° of flexion. Knee laxity was measured by three separate independent investigators through a knee laxity tester.
RESULTS: One hundred and eighty-six participants (95 females) were enrolled in the study. Among them, 108 Malaysians participated. The Jordanians had significantly higher knee laxity in both knees compared with the Malaysians. The mean average right knee laxity for Jordanians was 2.98 mm vs. 2.72 mm for Malaysians (P = 0.005). Similarly, the mean average left knee laxity for Jordanians was 2.95 mm, while for Malaysians, it was 2.62 mm (P = 0.0001). Furthermore, smokers had significantly more laxity in both knees. After performing a multivariate linear regression analysis for all factors, race was the only independent factor that affected knee laxity in both knees.
CONCLUSIONS: Race is directly associated with knee laxity. Jordanians tend to have more laxity in knee joints compared with Malaysians. Larger multi-center and genetic studies are recommended to establish the racial differences between different ethnic groups.

Matched MeSH terms: Range of Motion, Articular/physiology*
The effect of motion and signalling on drivers' ability to predict intentions of other road users

Lee YM, Sheppard E

Accid Anal Prev, 2016 Oct;95(Pt A):202-8.
PMID: 27450792 DOI: 10.1016/j.aap.2016.07.011

Failure in making the correct judgment about the intention of an approaching vehicle at a junction could lead to a collision. This paper investigated the impact of dynamic information on drivers' judgments about the intentions of approaching cars and motorcycles, and whether a valid or invalid signal was provided was also manipulated. Participants were presented with videoclips of vehicles approaching a junction which terminated immediately before the vehicle made any manoeuvre, or images of the final frame of each video. They were asked to judge whether or not the vehicle would turn. Drivers were better in judging the manoeuvre of approaching vehicles in dynamic than static stimuli, for both vehicle types. Drivers were better in judging the manoeuvre of cars than motorcycles for videos, but not for photographs. Drivers were also better in judging the manoeuvre of approaching vehicles when a valid signal was provided than an invalid signal, demonstrating the importance of providing a valid signal while driving. However, drivers were still somewhat successful in their judgments in most of the conditions with an invalid signal, suggesting that drivers were able to focus on other cues to intention. Finally, given that dynamic stimuli more closely reflect the demands of real-life driving there may be a need for drivers to adopt a more cautious approach while inferring a motorcyclist's intentions.

Matched MeSH terms: Motion Perception*
Changes in organisation of instep kicking as a function of wearing compression and textured materials

Hasan H, Davids K, Chow JY, Kerr G

Eur J Sport Sci, 2017 Apr;17(3):294-302.
PMID: 27739339 DOI: 10.1080/17461391.2016.1241829

This study investigated effects of wearing compression garments and textured insoles on modes of movement organisation emerging during performance of lower limb interceptive actions in association football. Participants were six skilled (age = 15.67 ± 0.74 years) and six less-skilled (age = 15.17 ± 1.1 years) football players. All participants performed 20 instep kicks with maximum velocity in four randomly organised insoles and socks conditions, (a) Smooth Socks with Smooth Insoles (SSSI); (b) Smooth Socks with Textured Insoles (SSTI); (c) Compression Socks with Smooth Insoles (CSSI); and (d), Compression Socks with Textured Insoles (CSTI). Results showed that, when wearing textured and compression materials (CSSI condition), less-skilled participants displayed significantly greater hip extension and flexion towards the ball contact phase, indicating larger ranges of motion in the kicking limb than in other conditions. Less-skilled participants also demonstrated greater variability in knee-ankle intralimb (angle-angle plots) coordination modes in the CSTI condition. Findings suggested that use of textured and compression materials increased attunement to somatosensory information from lower limb movement, to regulate performance of dynamic interceptive actions like kicking, especially in less-skilled individuals.

Matched MeSH terms: Range of Motion, Articular/physiology
Biomechanical investigation on the influence of the regional material degeneration of an intervertebral disc in a lower lumbar spinal unit: A finite element study

Masni-Azian, Tanaka M

Comput Biol Med, 2018 07 01;98:26-38.
PMID: 29758454 DOI: 10.1016/j.compbiomed.2018.05.010

Intervertebral disc degeneration involves changes in its material properties that affect the mechanical functions of the spinal system. However, the alteration of the biomechanics of a spinal segment through specific material degradation in a specific region is poorly understood. In this study, the influence of the constitutive material degeneration of disc tissues on the mechanics of a lower lumbar spinal unit was examined using a three-dimensional nonlinear finite element model of the L4-L5 functional spinal unit. Different grades of disc degeneration were simulated by introducing a degeneration factor to the corresponding material properties to represent fibrous nucleus, increased fibre and ground substance laxity, increased fibre stiffness and total annular fracture along posterior and posterolateral regions. The model was loaded with an axial compression of 500 N and pure moments of up to 10 Nm to simulate extension, flexion, lateral bending and axial rotation. To validate the model, the spinal motion and intradiscal pressure of healthy and degenerated discs with existing in vitro data were compared. The disc with a fibrous nucleus and the presence of intradiscal pressure increase the spinal instability during flexion and axial rotation, and the absence of intradiscal pressure increases the spinal instability in all directions. Bulging displacement and shear strains in the disc with total fracture and ground substance laxity are high in all of the loading cases. Our study could provide useful information to enhance our understanding of the influence of each constitutive component of the intervertebral disc on the mechanics of the spinal segment.

Matched MeSH terms: Range of Motion, Articular/physiology
Statistical factorial analysis approach for parameter calibration on material nonlinearity of intervertebral disc finite element model

Masni-Azian, Tanaka M

Comput Methods Biomech Biomed Engin, 2017 Aug;20(10):1066-1076.
PMID: 28532164 DOI: 10.1080/10255842.2017.1331345

In the biomechanics field, material parameters calibration is significant for finite element (FE) model to ensure a legit estimation of biomechanical response. Determining an appropriate combination of calibration factors is challenging as each constitutive component responds differently. This study proposes a statistical factorial analysis approach using L16(4(5)) orthogonal array to evaluate material nonlinearity and applicable calibration factor of the intervertebral disc FE model in pure moment. The calibrated model exhibits improved agreement to the experimental findings for all directions. Appropriate combination of calibration parameter reduces the estimation gap to the experimental findings, ensuring agreeable biomechanical responses.

Matched MeSH terms: Range of Motion, Articular/physiology
In silico study of glenoid perforation during total shoulder arthroplasty: the effects on stress & micromotion

Wahab AHA, Saad APM, Syahrom A, Kadir MRA

Comput Methods Biomech Biomed Engin, 2020 Apr;23(5):182-190.
PMID: 31910663 DOI: 10.1080/10255842.2019.1709828

Glenoid perforation is not the intended consequence of the surgery and must be avoided. The analysis on biomechanical aspect of glenoid vault perforation remains unknown. The purpose of this study is to determine the impact of glenoid perforation towards stress distribution and micromotion at the interfaces. Eight glenoid implant models had been constructed with various size, number and type of fixation. A load of 750 N was applied to centre, superior-anterior and superior-posterior area. Implant perforation had minimal impact on stress distribution and micromotion at the interfaces. However, cement survival rate for implant without perforation was the highest with a difference of up to 37% compared to other perforated models. Besides that, implant fixation and high stresses at the implant had more of an impact on implant instability than implant perforation. As a conclusion, glenoid perforation did not influence the stress distribution and micromotion, but, it reduced cement survival rate and increase the stress critical volume.

Matched MeSH terms: Motion*
Fulltext Quantification of muscles activations and joints range of motions during oil palm fresh fruit bunch harvesting and loose fruit collection

Teo YX, Chan YS, Gouwanda D, Gopalai AA, Nurzaman SG, Thannirmalai S

Sci Rep, 2021 07 22;11(1):15020.
PMID: 34294775 DOI: 10.1038/s41598-021-94268-4

Although global demand for palm oil has been increasing, most activities in the oil palm plantations still rely heavily on manual labour, which includes fresh fruit bunch (FFB) harvesting and loose fruit (LF) collection. As a result, harvesters and/or collectors face ergonomic risks resulting in musculoskeletal disorder (MSD) due to awkward, extreme and repetitive posture during their daily work routines. Traditionally, indirect approaches were adopted to assess these risks using a survey or manual visual observations. In this study, a direct measurement approach was performed using Inertial Measurement Units, and surface Electromyography sensors. The instruments were attached to different body parts of the plantation workers to quantify their muscle activities and assess the ergonomics risks during FFB harvesting and LF collection. The results revealed that the workers generally displayed poor and discomfort posture in both activities. Biceps, multifidus and longissimus muscles were found to be heavily used during FFB harvesting. Longissimus, iliocostalis, and multifidus muscles were the most used muscles during LF collection. These findings can be beneficial in the design of various assistive tools which could improve workers' posture, reduce the risk of injury and MSD, and potentially improve their overall productivity and quality of life.

Matched MeSH terms: Range of Motion, Articular*
Dosimetric evaluation near lung and soft tissue interface region during respiratory-gated and non-gated radiotherapy: A moving phantom study

Jong WL, Ung NM, Vannyat A, Rosenfeld AB, Wong JHD

Phys Med, 2017 Oct;42:39-46.
PMID: 29173919 DOI: 10.1016/j.ejmp.2017.08.011

Challenges in treating lung tumours are related to the respiratory-induced tumour motion and the accuracy of dose calculation in charged particle disequilibrium condition. The dosimetric characteristics near the interface of lung and Perspex media in a moving phantom during respiratory-gated and non-gated radiotherapy were investigated using Gafchromic EBT2 and the MOSkin detector. The MOSkin detectors showed good agreement with the EBT2 films during static and gated radiotherapy. In static radiotherapy, the penumbral widths were found to be 3.66mm and 7.22mm in Perspex and lung media, respectively. In non-gated (moving) radiotherapy with 40mm respiratory amplitude, dose smearing effect was observed and the penumbral widths were increased to 28.81mm and 26.40mm, respectively. This has been reduced to 6.85mm and 9.81mm, respectively, in gated radiotherapy with 25% gating window. There were still some dose discrepancies as compared to static radiotherapy due to the residual motion. This should be taken into account in the margin generation for the target tumour.

Matched MeSH terms: Motion*
Fulltext Dynamic finite element analysis of mobile bearing type knee prosthesis under deep flexional motion

Anuar MA, Todo M, Nagamine R, Hirokawa S

ScientificWorldJournal, 2014;2014:586921.
PMID: 25133247 DOI: 10.1155/2014/586921

The primary objective of this study is to distinguish between mobile bearing and fixed bearing posterior stabilized knee prostheses in the mechanics performance using the finite element simulation. Quantifying the relative mechanics attributes and survivorship between the mobile bearing and the fixed bearing prosthesis remains in investigation among researchers. In the present study, 3-dimensional computational model of a clinically used mobile bearing PS type knee prosthesis was utilized to develop a finite element and dynamic simulation model. Combination of displacement and force driven knee motion was adapted to simulate a flexion motion from 0° to 135° with neutral, 10°, and 20° internal tibial rotation to represent deep knee bending. Introduction of the secondary moving articulation in the mobile bearing knee prosthesis has been found to maintain relatively low shear stress during deep knee motion with tibial rotation.

Matched MeSH terms: Range of Motion, Articular
Fulltext Development of biological movement recognition by interaction between active basis model and fuzzy optical flow division

Yousefi B, Loo CK

ScientificWorldJournal, 2014;2014:238234.
PMID: 24883361 DOI: 10.1155/2014/238234

Following the study on computational neuroscience through functional magnetic resonance imaging claimed that human action recognition in the brain of mammalian pursues two separated streams, that is, dorsal and ventral streams. It follows up by two pathways in the bioinspired model, which are specialized for motion and form information analysis (Giese and Poggio 2003). Active basis model is used to form information which is different from orientations and scales of Gabor wavelets to form a dictionary regarding object recognition (human). Also biologically movement optic-flow patterns utilized. As motion information guides share sketch algorithm in form pathway for adjustment plus it helps to prevent wrong recognition. A synergetic neural network is utilized to generate prototype templates, representing general characteristic form of every class. Having predefined templates, classifying performs based on multitemplate matching. As every human action has one action prototype, there are some overlapping and consistency among these templates. Using fuzzy optical flow division scoring can prevent motivation for misrecognition. We successfully apply proposed model on the human action video obtained from KTH human action database. Proposed approach follows the interaction between dorsal and ventral processing streams in the original model of the biological movement recognition. The attained results indicate promising outcome and improvement in robustness using proposed approach.

Matched MeSH terms: Motion Perception
Fulltext A comparison between subvastus and midvastus approaches for staged bilateral total knee arthroplasty:a prospective, randomised study

Masjudin T, Kamari Zh

Malays Orthop J, 2012 Nov;6(3):31-6.
PMID: 25279053 DOI: 10.5704/MOJ.1207.0018

This prospective randomised study was undertaken to compare surgical parameters as well as clinical and radiological outcomes of subvastus (SV) to midvastus (MV) approaches in staged bilateral total knee arthroplasty (TKA). Twenty-three patients, aged 55-76 years, who underwent staged bilateral TKAs, were followed up for 6 months. The SV approach was used on one knee and MV approach on the other. We found similar lateral retinacular release rates and patellar resurfacing rates between the two approaches .The SV approached knees had a more significant blood loss and increased operative time compared to the MV approached knees but they achieved significantly earlier active straightleg raises (SLR) postoperatively (p<0.05 for all). The average postoperative pain, flexion, and Knee Society scores were comparable for both approaches. TKA via SV vs. MV approaches provides comparable satisfactory short-term clinical and radiological outcomes, even though there was slightly more difficulty, more blood loss and longer operative times with the SV approach.

Matched MeSH terms: Range of Motion, Articular
Fulltext View-Invariant Visuomotor Processing in Computational Mirror Neuron System for Humanoid

Dawood F, Loo CK

PLoS One, 2016;11(3):e0152003.
PMID: 26998923 DOI: 10.1371/journal.pone.0152003

Mirror neurons are visuo-motor neurons found in primates and thought to be significant for imitation learning. The proposition that mirror neurons result from associative learning while the neonate observes his own actions has received noteworthy empirical support. Self-exploration is regarded as a procedure by which infants become perceptually observant to their own body and engage in a perceptual communication with themselves. We assume that crude sense of self is the prerequisite for social interaction. However, the contribution of mirror neurons in encoding the perspective from which the motor acts of others are seen have not been addressed in relation to humanoid robots. In this paper we present a computational model for development of mirror neuron system for humanoid based on the hypothesis that infants acquire MNS by sensorimotor associative learning through self-exploration capable of sustaining early imitation skills. The purpose of our proposed model is to take into account the view-dependency of neurons as a probable outcome of the associative connectivity between motor and visual information. In our experiment, a humanoid robot stands in front of a mirror (represented through self-image using camera) in order to obtain the associative relationship between his own motor generated actions and his own visual body-image. In the learning process the network first forms mapping from each motor representation onto visual representation from the self-exploratory perspective. Afterwards, the representation of the motor commands is learned to be associated with all possible visual perspectives. The complete architecture was evaluated by simulation experiments performed on DARwIn-OP humanoid robot.

Matched MeSH terms: Motion
Oral biopsy turnaround time: 20-year experience of the Department of Oral Pathology, Oral Medicine and Periodontology, Faculty of Dentistry, University of Malaya

Siar CH, Tan BH

J Oral Sci, 2000 Dec;42(4):205-10.
PMID: 11269378

The turnaround time (TAT) for oral biopsies received for histological examination by the Department of Oral Pathology, Oral Medicine and Periodontology, Faculty of Dentistry, University of Malaya, for the years 1978, 1988 and 1998 was evaluated. For the three years studied, TATs for 61, 233 and 463 specimens were retrospectively analysed. Testing intervals, that is, from the dates the surgeons procured the specimens, the laboratories accessioned them and until the pathologists signed off the diagnoses, were used to calculate TAT. The performance level of the respective pathologists, the growth of tissue diagnostic services and the possible variables that influence TAT were also evaluated. As prompt diagnosis means prompt treatment, which in turn has a bearing on prognosis, the TAT pertinent to oral malignant tumors was emphasized. The mean TAT, its mode and median fell significantly in 1998 compared with the previous 2 years; it was lower for soft tissue than for hard tissue specimens, and lower for malignant, than for non-malignant specimens. The progression of tissue diagnostic services is up to a satisfactory level, as 88.89 % of biopsies could render diagnoses within a fair period of time in 1998.

Matched MeSH terms: Time and Motion Studies
Periprosthetic Fractures after Total Knee Arthroplasty: the Influence of Pre-Operative Mechanical Factors versus Intraoperative Factors

Zainul-Abidin S, Lim B, Bin-Abd-Razak HR, Gatot C, Allen JC, Koh J, et al.

Malays Orthop J, 2019 Jul;13(2):28-34.
PMID: 31467648 DOI: 10.5704/MOJ.1907.005

Introduction: Periprosthetic fractures are a devastating complication following total knee arthroplasty. Little is known about the effect of mechanical factors on the incidence of periprosthetic fractures. The aim of this study was to examine the correlation between pre-operative mechanical factors, like side of surgery, coronal alignment and pre-operative range of motion and intra-operative factors, and the incidence of a periprosthetic fracture, following primary total knee arthroplasty (TKA). Materials and Methods: Forty-two patients with periprosthetic fractures (PPF) after primary TKA were identified from our hospital arthroplasty registry. These patients were matched two-to-one for gender and age at primary knee arthroplasty to 84 patients without PPF. The incidence of periprosthetic fracture with regards to laterality, coronal alignment and pre-operative range of motion was analysed. Intra-operative factors like implant type, patellar resurfacing and notching were also analysed using logistic regression. Results: Coronal alignment, pre-operative range of motion and patella resurfacing were not significant predictors of periprosthetic fractures. Anterior femoral notching was found to be significantly higher in the fracture group with an odds ratio of 17. Left sided surgery was also significantly higher in the periprosthetic fracture group. Conclusion: Periprosthetic fractures are 17 times more likely to occur in a knee with anterior femoral notching. Preoperative factors like coronal alignment and poor preoperative range of motion do not seem to increase the risk of periprosthetic fractures after TKA.

Matched MeSH terms: Range of Motion, Articular

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