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Söderqvist K, Identeg F, Zimmerman J, Senorski EH, Sansone M, Hedelin H. Validity and Reliability of Finger-Strength Testing in 6 Common Grip Techniques for the Assessment of Bouldering Ability in Men. Int J Sports Physiol Perform 2024; 19:290-298. [PMID: 38307010 DOI: 10.1123/ijspp.2023-0129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 11/11/2023] [Accepted: 11/15/2023] [Indexed: 02/04/2024]
Abstract
OBJECTIVE To determine the criterion validity and test-retest reliability of isometric finger-strength testing in 6 differentiated grip techniques for the assessment of bouldering ability among male climbers. METHODS We recruited participants at climbing gyms in Sweden and through online advertisements. We included climbers over 15 years of age with a minimum bouldering performance level of 17 International Rock Climbing and Research Association (IRCRA) for men and 15 IRCRA for women. We tested unilateral, maximal isometric peak finger strength in the front 3 drag, half crimp, closed crimp, 35 sloper, 45 × 90-mm, and 90 × 90-mm pinch through maximal force deloaded of a force plate. We analyzed criterion validity, test-retest reliability, and capacity to determine bouldering performance ability using a stepwise multivariable regression model. RESULTS Women were excluded from the analysis due to insufficient sample size (n = 16). Thirty-two male participants were included in the primary analysis. The median (interquartile range) age in the advanced and elite group was 27 (25; 35) and 23 (22; 32) years, respectively. The half crimp for the participants' weak and strong hand displayed the highest ability to determine bouldering grade performance, explaining 48% to 58% of the variance. In the stepwise regression, maximal strength in the half crimp and the front 3 drag collectively explained 66% of the variance for performance. CONCLUSION Strength in the half crimp proved the most important performance indicator. The results of this study provide a reliable and valid framework for maximal isometric peak finger-strength testing in advanced and elite male boulderers.
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Affiliation(s)
- Karl Söderqvist
- Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Fredrik Identeg
- Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Jonas Zimmerman
- Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Eric Hamrin Senorski
- Department of Health and Rehabilitation, Institute of Neuroscience and Physiology, Sahgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Mikael Sansone
- Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Hedelin
- Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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Wu X, Chen M, Lin S, Chen S, Gu J, Wu Y, Qu M, Gong W, Yao Q, Li H, Zou X, Chen D, Xiao G. Loss of Pinch Proteins Causes Severe Degenerative Disc Disease-Like Lesions in Mice. Aging Dis 2023; 14:1818-1833. [PMID: 37196110 PMCID: PMC10529740 DOI: 10.14336/ad.2023.0212] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Accepted: 02/12/2023] [Indexed: 05/19/2023] Open
Abstract
Degenerative disc disease (DDD) is one of the most common skeletal disorders affecting aged populations. DDD is the leading cause of low back/neck pain, resulting in disability and huge socioeconomic burdens. However, the molecular mechanisms underlying DDD initiation and progression remain poorly understood. Pinch1 and Pinch2 are LIM-domain-containing proteins with crucial functions in mediating multiple fundamental biological processes, such as focal adhesion, cytoskeletal organization, cell proliferation, migration, and survival. In this study, we found that Pinch1 and Pinch2 were both highly expressed in healthy intervertebral discs (IVDs) and dramatically downregulated in degenerative IVDs in mice. Deleting Pinch1 in aggrecan-expressing cells and Pinch2 globally (AggrecanCreERT2; Pinch1fl/fl; Pinch2-/-) caused striking spontaneous DDD-like lesions in lumbar IVDs in mice. Pinch loss inhibited cell proliferation and promoted extracellular matrix (ECM) degradation and apoptosis in lumbar IVDs. Pinch loss markedly enhanced the production of pro-inflammatory cytokines, especially TNFα, in lumbar IVDs and exacerbated instability-induced DDD defects in mice. Pharmacological inhibition of TNFα signaling mitigated the DDD-like lesions caused by Pinch loss. In human degenerative NP samples, reduced expression of Pinch proteins was correlated with severe DDD progression and a markedly upregulated expression of TNFα. Collectively, we demonstrate the crucial role of Pinch proteins in maintaining IVD homeostasis and define a potential therapeutic target for DDD.
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Affiliation(s)
- Xiaohao Wu
- Department of Biochemistry, School of Medicine, Shenzhen Key Laboratory of Cell Microenvironment, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Southern University of Science and Technology, Shenzhen, China.
| | - Mingjue Chen
- Department of Biochemistry, School of Medicine, Shenzhen Key Laboratory of Cell Microenvironment, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Southern University of Science and Technology, Shenzhen, China.
| | - Sixiong Lin
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
| | - Sheng Chen
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei, China.
| | - Jingliang Gu
- Department of Orthopedics, Shanghai municipal Hospital of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, China.
| | - Yuchen Wu
- Department of Endocrinology, Chongqing Traditional Chinese Medicine Hospital, Chongqing, China.
| | - Minghao Qu
- Department of Biochemistry, School of Medicine, Shenzhen Key Laboratory of Cell Microenvironment, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Southern University of Science and Technology, Shenzhen, China.
| | - Weiyuan Gong
- Department of Biochemistry, School of Medicine, Shenzhen Key Laboratory of Cell Microenvironment, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Southern University of Science and Technology, Shenzhen, China.
| | - Qing Yao
- Department of Biochemistry, School of Medicine, Shenzhen Key Laboratory of Cell Microenvironment, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Southern University of Science and Technology, Shenzhen, China.
| | - Huiping Li
- Department of Respiratory and Critical Care Medicine, Shenzhen People’s Hospital, Southern University of Science and Technology, Shenzhen, China.
| | - Xuenong Zou
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
| | - Di Chen
- Research Center for Human Tissues and Organs Degeneration, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
| | - Guozhi Xiao
- Department of Biochemistry, School of Medicine, Shenzhen Key Laboratory of Cell Microenvironment, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Southern University of Science and Technology, Shenzhen, China.
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Stefan RR, Camic CL, Miles GF, Kovacs AJ, Jagim AR, Hill CM. Relative Contributions of Handgrip and Individual Finger Strength on Climbing Performance in a Bouldering Competition. Int J Sports Physiol Perform 2022;:1-6. [PMID: 35235904 DOI: 10.1123/ijspp.2021-0422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/19/2021] [Accepted: 10/27/2021] [Indexed: 11/18/2022]
Abstract
PURPOSE To determine the relative contributions of handgrip and individual finger strength for the prediction of climbing performance in a bouldering competition. A secondary aim was to examine the influence of body size, bouldering experience, and training habits. METHODS Sixty-seven boulderers (mean [SD], age = 21.1 [4.0] y; body mass = 69.5 [9.8] kg) volunteered for this study. Data collection occurred immediately before an indoor bouldering competition and involved the assessment of handgrip and individual finger maximal force production using an electronic handheld dynamometer. The bouldering competition consisted of 70 routes graded V0 to V8, with higher point values awarded for completing more difficult routes. Stepwise multiple regression analysis was used to examine the relative contributions of handgrip and individual finger strengths, body mass, height, bouldering experience, and bouldering frequency to the prediction of performance scores in the competition. RESULTS Ring finger pinch strength, bouldering experience, and bouldering frequency significantly (P < .05) contributed to the model (R2 = .373), whereas body mass; height; full handgrip strength, as well as index, middle, and little finger pinch strengths did not. The β weights showed that ring finger pinch strength (β = .430) was the most significant contributor, followed by bouldering experience (β = .331) and bouldering frequency (β = .244). CONCLUSIONS The current findings indicated that trainable factors contributed to the prediction of bouldering performance. These results suggest greater bouldering frequency and experience likely contribute to greater isolated individual finger strength, thereby optimizing preparation for the diverse handholds in competitive rock climbing.
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Piacenza A, Vittonetto D, Rossello MI, Testa M. Arthrodesis Versus Arthroplasty in Thumb Carpometacarpal Osteoarthritis: Impact on Maximal Voluntary Force, Endurance, and Accuracy of Pinch. J Hand Surg Am 2022; 47:90.e1-90.e7. [PMID: 34045112 DOI: 10.1016/j.jhsa.2021.03.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 01/16/2021] [Accepted: 03/12/2021] [Indexed: 02/02/2023]
Abstract
PURPOSE To investigate differences in pinch strength recovery among patients with first carpometacarpal joint osteoarthritis treated with either arthrodesis or suspension arthroplasty. METHODS Thirty-seven subjects who underwent arthrodesis or suspension arthroplasty for carpometacarpal osteoarthritis were included. Force exerted during maximal voluntary contraction (MVC) in a pinch task was measured. Maximal voluntary contraction was recorded using a haptic device equipped with a load cell from which an analog signal was acquired and digitized for visual feedback. Dynamic force was assessed by a task consisting of 10 repetitions, with a target of 70% of MVC. Endurance was assessed by the length of sustained pinch task at 30% of MVC. Task performance was quantified by mean distance and offset error from the target force as error indices, and standard deviation of force was used as index of force steadiness. RESULTS The arthrodesis group obtained considerably higher MVC values than the arthroplasty group. No notable differences were found for pinch endurance. The standard deviation for dynamic force was lower for arthroplasty, indicating greater force steadiness. CONCLUSIONS Arthrodesis is associated with greater pinch strength. Arthroplasty is associated with better pinch precision. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.
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Affiliation(s)
- Alberto Piacenza
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genova, Italy; Department of Recovery and Functional Reeducation Unit, Santa Corona Hospital, Pietra Ligure, Italy
| | - Debora Vittonetto
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genova, Italy
| | | | - Marco Testa
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genova, Italy.
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Dottor A, Camerone E, Job M, Barbiani D, Frisaldi E, Testa M. A new visual feedback-based system for the assessment of pinch force, endurance, accuracy and precision. A test-retest reliability study. Hand Ther 2021; 26:53-62. [PMID: 37969174 PMCID: PMC10634379 DOI: 10.1177/17589983211002550] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 02/17/2021] [Indexed: 11/17/2023]
Abstract
Introduction Given that pinch is a precision grip involved in sustained submaximal activities, a Sustained Contraction (SC) task could be associated to Maximal Voluntary Contraction (MVC). To better evaluate the thumb-index system, the test-retest reliability of pinch MVC and SC, measured by a visual feedback-based pinch gauge was assessed. Methods 26 healthy participants performed MVC and SC in two separate sessions. SC required to maintain 40%MVC as long as possible and it was evaluated in terms of time, accuracy (Mean Distance between force trace and target force, MD), precision (Coefficient of Variability of force trace, CV). MD and CV analyses were conducted dividing the SC task into three equivalent time stages (beginning, middle, exhaustion). Relative Reliability (RR) was measured by Intraclass Correlation Coefficient, and Absolute Reliability (AR) was measured by Standard Error of Measurement and by Bland-Altman plot. Results MVC and Time showed high RR and AR in both hands. RR of MD and CV in right hand was excellent in the beginning and middle stages, and fair in the exhaustion one, showing decreasing reliability as fatigue increases. In the left hand RR of MD and CV was generally lower. MD showed excellent reliability in the beginning stage and good reliability in the other stages. CV showed fair relative reliability at both beginning and middle stages, excellent in the last one. Conversely, it was observed high AR of MD and CV in all stages in both hands. Conclusions All indices are reliable to assess motor control of thumb-index pinch in both hands.
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Affiliation(s)
- Alberto Dottor
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Eleonora Camerone
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Mirko Job
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Diletta Barbiani
- Department of Neuroscience, University of Turin Medical School, Turin, Italy
| | - Elisa Frisaldi
- Department of Neuroscience, University of Turin Medical School, Turin, Italy
| | - Marco Testa
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
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Symons J. Mechanical Effect of Performance Pressure Boots on Cadaveric Equine Hindlimb Fetlock Biomechanics. Animals (Basel) 2021; 11:ani11040958. [PMID: 33808243 PMCID: PMC8066513 DOI: 10.3390/ani11040958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/22/2021] [Accepted: 03/26/2021] [Indexed: 11/26/2022] Open
Abstract
Simple Summary Pressure boots are performance enhancing equipment used by showjumping horses. Showjumping is scored by knocked down obstacle rails and time. Similar to weighted boots, pressure boots are intended to improve the hindlimb retraction of jumping horses to reduce the likelihood of knocking down rails on course. Manufacturers describe pressure boots as using acupressure to improve a horse’s awareness of their own limbs. However, this mechanism has not been verified within the scientific literature. The size and shape of features on the interior boot surface suggest a mechanical mechanism may affect anatomical structures within the lower limb. This research aims to characterize the mechanical effect of pressure boots by measuring forces and joint angles of cadaveric limbs with and without a pressure boot applied. Cadaveric limbs with a pressure boot applied required greater compressive loads to flex the fetlock joint than limbs without a pressure boot applied. This difference in compressive loads increased with increasing fetlock flexion angle. Differences in limb compressive loads contributed to greater tensile loads of palmar tendons and ligaments, specifically the suspensory apparatus. Greater tensile loading of tendons and ligaments may increase the likelihood of musculoskeletal injury and warrant concern for animal welfare of equine showjumping athletes. Abstract Pressure boots are applied to hind limbs of showjumping horses with the intent to enhance jumping form. Manufacturers claim acupressure points enhance proprioception of hind limbs. With this increased awareness, horses are expected to retract their hind limbs to clear jump rails. This research aimed to investigate a more direct, mechanical effect of pressure boots on hind limb biomechanics. Cadaveric hind limbs (n = 6) were mechanically loaded in axial compression (3 cycles at 0.25 Hz, displacement control ~3300 N) with (2 trials) and without (2 trials) a pressure boot applied. During mechanical loading, fetlock angle was measured using bone fixed pins with retroreflective markers (30 Hz). Changes in limb load and fetlock angle between unloaded and loaded states, as well as average fetlock joint stiffness, were compared between trials with and without the pressure boot via ANOVA. Differences in measured loads between trials with and without the boot were observed in both unloaded (Δ = 6 N, p = 0.05) and loaded states (Δ = 25 N, p = 0.002). Trials with the boot had greater average fetlock stiffness (Δ = 3 N/degree, p = 0.001). Differences in loads with and without boots may increase with greater fetlock angles when cantering and jumping. These mechanical effects of pressure boots may contribute to greater tensile loading of palmar tendons and ligaments, and likelihood of musculoskeletal injury that can be related to animal welfare issues.
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Affiliation(s)
- Jennifer Symons
- Shiley School of Engineering, University of Portland, Portland, OR 97203, USA
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Lo VEW, Chao SM, Tu HH. Normative Hand Strength of Healthcare Industry Workers in Central Taiwan. Int J Environ Res Public Health 2020; 18:ijerph18010187. [PMID: 33383773 PMCID: PMC7795098 DOI: 10.3390/ijerph18010187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/20/2020] [Accepted: 12/25/2020] [Indexed: 11/30/2022]
Abstract
Objectives: The purpose of this study is to establish the norms of hand grip strength in the healthcare industry in Taiwan and propose models to predict the strength of hand movement by regression with demographic and anthropometric factors. Methods: This is a cross-sectional study with a stratified convenience sample of workers in healthcare service industries in central Taiwan. Three hundred twenty-nine healthy subjects were recruited. Strength of different hand movement were tested three times in both hands and rests were given between tests. Results: Female strength of these hand movement was 59.1% to 73.0% that in males (p < 0.001). In general, the hand strength of male workers in the healthcare industry was less than that of male workers in the manufacturing industry (p < 0.001). In the prediction model, sex and weight played important roles in predicting hand strength. Conclusions: The norms of different types of hand strength was investigated the first time in workers in the healthcare industry in Taiwan. The tasks performed by healthcare personnel vary widely, and this variable should be considered in a future prediction model.
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Affiliation(s)
- Victor Ei-Wen Lo
- Department of Occupational Safety and Health, China Medical University, Taichung City 40604, Taiwan;
- Correspondence: ; Tel.: +886-4-2296-7979 (ext. 6213)
| | - Shu-Min Chao
- Department of Occupational Safety and Health, China Medical University, Taichung City 40604, Taiwan;
| | - Hsin-Hung Tu
- Department of Computer-Aided Industrial Design, Overseas Chinese University, Taichung City 40721, Taiwan;
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Li L, Li Y, Wang H, Chen W, Liu X. Effect of Force Level and Gender on Pinch Force Perception in Healthy Adults. Iperception 2020; 11:2041669520927043. [PMID: 32547724 PMCID: PMC7249577 DOI: 10.1177/2041669520927043] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 04/25/2020] [Indexed: 11/29/2022] Open
Abstract
This study investigated the effects of both force level and gender on pinch force reproduction errors in normal participants during an ipsilateral force reproduction task. In total, 20 healthy participants were asked to generate a range of levels of reference forces ranging from 5% to 60% maximal voluntary isometric contraction (MVIC) in increments of 5% MVIC using the tip pinch and to reproduce these forces using the same hand. The results showed that the males more accurately and consistently reproduced the forces than did the females, and the most accurate estimation occurred at approximately 20% to 35% MVIC. This finding can help us better understand the reasons for the higher rate of musculoskeletal disorders in females than in males and to develop tools and preventive strategies to decrease the rate of hand injuries in both genders.
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Affiliation(s)
- Lin Li
- Department of Physical Education, Renmin University of China
| | - Yanxia Li
- College of Physical Education, Langfang Teachers University, Hebei, China
| | - Huihui Wang
- School of Physical Education, Zunyi Medical University, Guizhou, China
| | - Wenqi Chen
- School of Sociology and Population Studies, Renmin University of China
| | - Xinyu Liu
- School of Sociology and Population Studies, Renmin University of China
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Cole TS, Almefty KK, Godzik J, Muma AH, Hlubek RJ, Martinez-Del-Campo E, Theodore N, Kakarla UK, Turner JD. Functional improvement in hand strength and dexterity after surgical treatment of cervical spondylotic myelopathy: a prospective quantitative study. J Neurosurg Spine 2020; 32:1-7. [PMID: 32032958 DOI: 10.3171/2019.10.spine19685] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 10/28/2019] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Cervical spondylotic myelopathy (CSM) is the primary cause of adult spinal cord dysfunction. Diminished hand strength and reduced dexterity associated with CSM contribute to disability. Here, the authors investigated the impact of CSM severity on hand function using quantitative testing and evaluated the response to surgical intervention. METHODS Thirty-three patients undergoing surgical treatment of CSM were prospectively enrolled in the study. An occupational therapist conducted 3 functional hand tests: 1) palmar dynamometry to measure grip strength, 2) hydraulic pinch gauge test to measure pinch strength, and 3) 9-hole peg test (9-HPT) to evaluate upper extremity dexterity. Tests were performed preoperatively and 6-8 weeks postoperatively. Test results were expressed as 1) a percentile relative to age- and sex-stratified norms and 2) achievement of a minimum clinically important (MCI) difference. Patients were stratified into groups (mild, moderate, and severe myelopathy) based on their modified Japanese Orthopaedic Association (mJOA) score. The severity of stenosis on preoperative MRI was graded by three independent physicians using the Kang classification. RESULTS The primary presenting symptoms were neck pain (33%), numbness (21%), imbalance (12%), and upper extremity weakness (12%). Among the 33 patients, 61% (20) underwent anterior approach decompression, with a mean (SD) of 2.9 (1.5) levels treated. At baseline, patients with moderate and low mJOA scores (indicating more severe myelopathy) had lower preoperative pinch (p < 0.001) and grip (p = 0.01) strength than those with high mJOA scores/mild myelopathy. Postoperative improvement was observed in all hand function domains except pinch strength in the nondominant hand, with MCI differences at 6 weeks ranging from 33% of patients in dominant-hand strength tests to 73% of patients in nondominant-hand dexterity tests. Patients with moderate baseline mJOA scores were more likely to have MCI improvement in dominant grip strength (58.3%) than those with low mJOA scores/severe myelopathy (30%) and high mJOA scores/mild myelopathy (9%, p = 0.04). Dexterity in the dominant hand as measured by the 9-HPT ranged from < 1 in patients with cord signal change to 15.9 in patients with subarachnoid effacement only (p = 0.03). CONCLUSIONS Patients with CSM achieved significant improvement in strength and dexterity postoperatively. Baseline strength measures correlated best with the preoperative mJOA score; baseline dexterity correlated best with the severity of stenosis on MRI. The majority of patients experienced MCI improvements in dexterity. Baseline pinch strength correlated with postoperative mJOA MCI improvement, and patients with moderate baseline mJOA scores were the most likely to have improvement in dominant grip strength postoperatively.
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Chen CE, Wang TH. A modified technique for high-tension wound closure. J Am Acad Dermatol 2019; 83:e339-e340. [PMID: 31279021 DOI: 10.1016/j.jaad.2019.06.1298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Revised: 06/18/2019] [Accepted: 06/26/2019] [Indexed: 11/17/2022]
Affiliation(s)
- Ching-En Chen
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Surgery, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Tien-Hsiang Wang
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Surgery, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
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Kim YR, Kim CE, Yoon H, Kim SK, Kim SJ. S1 Employs Feature-Dependent Differential Selectivity of Single Cells and Distributed Patterns of Populations to Encode Mechanosensations. Front Cell Neurosci 2019; 13:132. [PMID: 31024261 PMCID: PMC6460949 DOI: 10.3389/fncel.2019.00132] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 03/18/2019] [Indexed: 11/23/2022] Open
Abstract
The primary somatosensory (S1) cortex plays an important role in the perception and discrimination of touch and pain mechanosensations. Conventionally, neurons in the somatosensory system including S1 cortex have been classified into low/high threshold (HT; non-nociceptive/nociceptive) or wide dynamic range (WDR; convergent) neurons by their electrophysiological responses to innocuous brush-stroke and noxious forceps-pinch stimuli. Besides this “noxiousness” (innocuous/noxious) feature, each stimulus also includes other stimulus features: “texture” (brush hairs/forceps-steel arm), “dynamics” (dynamic stroke/static press) and “intensity” (weak/strong). However, it remains unknown how S1 neurons inclusively process such diverse features of brushing and pinch at the single-cell and population levels. Using in vivo two-photon Ca2+ imaging in the layer 2/3 neurons of the mouse S1 cortex, we identified clearly separated response patterns of the S1 neural population with distinct tuning properties of individual cells to texture, dynamics and noxiousness features of cutaneous mechanical stimuli. Among cells other than broadly tuned neurons, the majority of the cells showed a highly selective response to the difference in texture, but low selectivity to the difference in dynamics or noxiousness. Between the two low selectivity features, the difference in dynamics was slightly more specific, yet both could be decoded using the response patterns of neural populations. In addition, more neurons are recruited and stronger Ca2+ responses are evoked as the intensity of forceps-pinch is gradually increased. Our results suggest that S1 neurons encode various features of mechanosensations with feature-dependent differential selectivity of single cells and distributed response patterns of populations. Moreover, we raise a caution about describing neurons by a single stimulus feature ignoring other aspects of the sensory stimuli.
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Affiliation(s)
- Yoo Rim Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, South Korea.,Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, South Korea
| | - Chang-Eop Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, South Korea.,Department of Physiology, College of Korean Medicine, Gachon University, Gyeonggi-do, South Korea
| | - Heera Yoon
- Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul, South Korea
| | - Sun Kwang Kim
- Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul, South Korea.,Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
| | - Sang Jeong Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, South Korea.,Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, South Korea.,Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, South Korea
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Kordi Yoosefinejad A, Ghaffarinejad F, Hemati M, Jamshidi N. Comparison of grip and pinch strength in young women with and without hyperkyphosis: A cross-sectional study. J Back Musculoskelet Rehabil 2019; 32:21-26. [PMID: 29865029 DOI: 10.3233/bmr-170932] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Hyperkyphosis is a common postural defect with high prevalence in the 20 to 50 year old population. It appears to compromise proximal scapular stability. Grip and pinch strength are used to evaluate general upper extremity function. OBJECTIVE The aim of this study was to compare pinch and grip strength between young women with and without hyperkyphosis. METHODS Thirty young women (18-40 years old) with hyperkyphosis and 30 healthy women matched for age and body mass index participated in the study. Hyperkyphosis was confirmed by measuring the kyphosis angle with a flexible ruler. Grip strength was measured with the Waisa method and a dynamometer. Pinch strength was assessed with a pinch meter. RESULTS Grip (P= 0.03) and pinch strength (P= 0.04) were significantly lower in women with hyperkyphosis compared to the control group. Kyphosis angle correlated weakly with grip (r= 0.26) and pinch strength (r= 0.23). CONCLUSIONS Hyperkyphotic posture has led to decreased grip and pinch strength compared to people without hyperkyphosis.
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Affiliation(s)
- Amin Kordi Yoosefinejad
- Physical Therapy Department, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.,Rehabilitation Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Farahnaz Ghaffarinejad
- Physical Therapy Department, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.,Rehabilitation Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mahbubeh Hemati
- Physical Therapy Department, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Narges Jamshidi
- Physical Therapy Department, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
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Sankar K, Patil S, Krishnamurthy S. Analysis of grip and pinch strength using inverse dynamics simulation technique. Proc Inst Mech Eng H 2018; 232:1063-1070. [PMID: 30175939 DOI: 10.1177/0954411918798400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Grip strength is the function of musculotendinous action across the finger joints and varies while dealing objects of varying size and shape. Increasing object size requires greater effort by the fingers to grip. The main objective of this study is to analyse the variation in grip and pinch strength exerted on objects of various sizes and shapes in a short span of time. OpenSim 3.3 is open-source musculoskeletal modelling software used for performing simulations in a dynamic environment. The generic wrist model in OpenSim has movements on index finger and thumb only, for study purpose. Objects of various sizes were designed and imported in OpenSim. This study determines the joint moments exerted by the fingers during grip activities. Original model was modified and custom joints were placed in the proximal and distal phalanx joints of the fingers. This allowed the finger segments to undergo translational and rotational movements. Coordinates of the custom joints were adjusted to provide constraints in the joint movement to hold the objects in position. For grip strength, objects of various sizes and shapes were imported to OpenSim. Simulation was carried out for gripping the objects for a specified time period. The force generated by the synergistic movements of finger segments was compared among grip and pinch of different objects. This method is used to determine the grip and pinch strength by handling objects of different shapes and sizes under the influence of time.
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Affiliation(s)
- Krishnakumar Sankar
- 1 Department of Translational Medicine and Research, SRM Medical College Hospital and Research Centre, SRM Institute of Science and Technology, Kattankulathur, India
| | - Shantanu Patil
- 1 Department of Translational Medicine and Research, SRM Medical College Hospital and Research Centre, SRM Institute of Science and Technology, Kattankulathur, India
| | - Sridhar Krishnamurthy
- 2 Institute of Craniofacial, Aesthetic and Plastic Surgery, SRM Institutes for Medical Science, Chennai, India
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Park S, Spirduso W, Eakin T, Abraham L. Force and Directional Force Modulation Effects on Accuracy and Variability in Low-Level Pinch Force Tracking. J Mot Behav 2017; 50:210-218. [PMID: 28846066 DOI: 10.1080/00222895.2017.1327412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The authors investigated how varying the required low-level forces and the direction of force change affect accuracy and variability of force production in a cyclic isometric pinch force tracking task. Eighteen healthy right-handed adult volunteers performed the tracking task over 3 different force ranges. Root mean square error and coefficient of variation were higher at lower force levels and during minimum reversals compared with maximum reversals. Overall, the thumb showed greater root mean square error and coefficient of variation scores than did the index finger during maximum reversals, but not during minimum reversals. The observed impaired performance during minimum reversals might originate from history-dependent mechanisms of force production and highly coupled 2-digit performance.
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Affiliation(s)
- Sangsoo Park
- a Department of Kinesiology , University of Massachusetts Amherst
| | - Waneen Spirduso
- b Department of Kinesiology and Health Education , The University of Texas at Austin
| | - Tim Eakin
- b Department of Kinesiology and Health Education , The University of Texas at Austin
| | - Lawrence Abraham
- b Department of Kinesiology and Health Education , The University of Texas at Austin
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Barden HLH, Baguley IJ, Nott MT, Heard R, Chapparo C. Computerised pinch dynamometry in the assessment of adult hand spasticity. Aust Occup Ther J 2014; 61:415-23. [PMID: 25331157 DOI: 10.1111/1440-1630.12141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/12/2014] [Indexed: 11/29/2022]
Abstract
BACKGROUND/AIM The hand engages with the environment through the grasp, stabilisation, manipulation and release of objects during everyday tasks, activities and routines. Upper motor neuron syndrome following acquired brain injury may negatively impact hand function, reducing strength, range of motion and motor control. It is important for clinicians to reliably measure such impacts, particularly for the impact of intervention and to monitor change in performance over time. Therefore, the aim of this study was to investigate the test-retest reliability and construct validity of Dynamic Computerised pinch Dynamometry for measuring fine hand motor performance following acquired brain injury. METHODS The Dynamic Computerised pinch Dynamometry protocol was completed by 36 community dwelling adults and 27 healthy adults using a simulated pinch and release task in lateral and pincer grip positions. Measurements were conducted over two testing occasions approximately five weeks apart. Dynamic Computerised pinch Dynamometry output was evaluated to determine the test-retest reliability and construct validity of the measure. RESULTS Test-retest reliability scores using Kendall coefficient of concordance ranged from W = 0.61-0.94. Dynamic Computerised pinch Dynamometry discriminated between participants with and without acquired brain injury (z = 4.97-6.50, P < 0.05) and between the affected and non-affected hand of participants with acquired brain injury (z = 3.37-5.22, P < 0.001). CONCLUSIONS Dynamic Computerised pinch Dynamometry in both lateral and pincer positions had fair to excellent test-retest reliability, and had good construct validity for discrimination between participants with and without acquired brain injury as well as between the affected and non-affected hand of participants with acquired brain injury.
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Affiliation(s)
- Hannah L H Barden
- Brain Injury Rehabilitation Service, Westmead Hospital, Wentworthville, Australia; Faculty of Health Sciences, The University of Sydney, Sydney, Australia
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Nishimura M, Kumsta C, Kaushik G, Diop SB, Ding Y, Bisharat-Kernizan J, Catan H, Cammarato A, Ross RS, Engler AJ, Bodmer R, Hansen M, Ocorr K. A dual role for integrin-linked kinase and β1-integrin in modulating cardiac aging. Aging Cell 2014; 13:431-40. [PMID: 24400780 PMCID: PMC4032615 DOI: 10.1111/acel.12193] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2013] [Indexed: 12/19/2022] Open
Abstract
Cardiac performance decreases with age, which is a major risk factor for cardiovascular disease and mortality in the aging human population, but the molecular mechanisms underlying cardiac aging are still poorly understood. Investigating the role of integrin-linked kinase (ilk) and β1-integrin (myospheroid, mys) in Drosophila, which colocalize near cardiomyocyte contacts and Z-bands, we find that reduced ilk or mys function prevents the typical changes of cardiac aging seen in wildtype, such as arrhythmias. In particular, the characteristic increase in cardiac arrhythmias with age is prevented in ilk and mys heterozygous flies with nearly identical genetic background, and they live longer, in line with previous findings in Caenorhabditis elegans for ilk and in Drosophila for mys. Consistent with these findings, we observed elevated β1-integrin protein levels in old compared with young wild-type flies, and cardiac-specific overexpression of mys in young flies causes aging-like heart dysfunction. Moreover, moderate cardiac-specific knockdown of integrin-linked kinase (ILK)/integrin pathway-associated genes also prevented the decline in cardiac performance with age. In contrast, strong cardiac knockdown of ilk or ILK-associated genes can severely compromise cardiac integrity, including cardiomyocyte adhesion and overall heart function. These data suggest that ilk/mys function is necessary for establishing and maintaining normal heart structure and function, and appropriate fine-tuning of this pathway can retard the age-dependent decline in cardiac performance and extend lifespan. Thus, ILK/integrin-associated signaling emerges as an important and conserved genetic mechanism in longevity, and as a new means to improve age-dependent cardiac performance, in addition to its vital role in maintaining cardiac integrity.
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Affiliation(s)
- Mayuko Nishimura
- Development, Aging and Regeneration Program; Sanford-Burnham Medical Research Institute; 10901 North Torrey Pines Road La Jolla CA 92037 USA
| | - Caroline Kumsta
- Development, Aging and Regeneration Program; Sanford-Burnham Medical Research Institute; 10901 North Torrey Pines Road La Jolla CA 92037 USA
| | - Gaurav Kaushik
- Sanford Consortium for Regenerative Medicine; University of California at San Diego; 2880 Torrey Pines Scenic Drive La Jolla CA 92037 USA
| | - Soda B. Diop
- Development, Aging and Regeneration Program; Sanford-Burnham Medical Research Institute; 10901 North Torrey Pines Road La Jolla CA 92037 USA
| | - Yun Ding
- School of Medicine; VA San Diego Healthcare System; University of California at San Diego; 3350 La Jolla Village Drive, Cardiology Section 111A San Diego CA 92161 USA
| | - Jumana Bisharat-Kernizan
- Development, Aging and Regeneration Program; Sanford-Burnham Medical Research Institute; 10901 North Torrey Pines Road La Jolla CA 92037 USA
| | - Hannah Catan
- Development, Aging and Regeneration Program; Sanford-Burnham Medical Research Institute; 10901 North Torrey Pines Road La Jolla CA 92037 USA
| | - Anthony Cammarato
- Division of Cardiology; Department of Medicine; School of Medicine; Johns Hopkins University; Baltimore MD 21287 USA
| | - Robert S. Ross
- School of Medicine; VA San Diego Healthcare System; University of California at San Diego; 3350 La Jolla Village Drive, Cardiology Section 111A San Diego CA 92161 USA
| | - Adam J. Engler
- Sanford Consortium for Regenerative Medicine; University of California at San Diego; 2880 Torrey Pines Scenic Drive La Jolla CA 92037 USA
| | - Rolf Bodmer
- Development, Aging and Regeneration Program; Sanford-Burnham Medical Research Institute; 10901 North Torrey Pines Road La Jolla CA 92037 USA
| | - Malene Hansen
- Development, Aging and Regeneration Program; Sanford-Burnham Medical Research Institute; 10901 North Torrey Pines Road La Jolla CA 92037 USA
| | - Karen Ocorr
- Development, Aging and Regeneration Program; Sanford-Burnham Medical Research Institute; 10901 North Torrey Pines Road La Jolla CA 92037 USA
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McGorry RW, Fallentin N, Andersen JH, Keir PJ, Hansen TB, Pransky G, Lin JH. Effect of grip type, wrist motion, and resistance level on pressures within the carpal tunnel of normal wrists. J Orthop Res 2014; 32:524-30. [PMID: 24391059 PMCID: PMC4305197 DOI: 10.1002/jor.22571] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 12/05/2013] [Indexed: 02/04/2023]
Abstract
Elevated carpal tunnel pressure (CTP) has been associated with carpal tunnel syndrome. This study systematically evaluated the effect of wrist motion resistance and grip type on CTP during wrist motion typical of occupational tasks. CTP during four wrist motion patterns, with and without resistance, and with and without gripping, was measured in vivo in 14 healthy individuals. CTP measured during compound motions fell between that measured in the cardinal planes of wrist flexion/extension and radial/ulnar deviation. Generally, with no active gripping there was little pressure change due to wrist angular displacement or resistance level. However, concurrent active pinch or power grip increased CTP particularly in motions including extension. CTP typically did not increase during wrist flexion, and in fact often decreased. Extension motions against resistance when employing a pinch or power grip increase CTP more than motions with flexion. Results could help inform design or modification of wrist motion intensive occupational tasks. © 2014 The Authors.
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Affiliation(s)
- Raymond W McGorry
- Liberty Mutual Research Institute for Safety71 Frankland Road, Hopkinton, Massachusetts, 01748
| | - Nils Fallentin
- Liberty Mutual Research Institute for Safety71 Frankland Road, Hopkinton, Massachusetts, 01748
| | - Johan H Andersen
- Danish Ramazzini Centre, Department of Occupational Medicine, Regional Hospital HerningHerning, Denmark
| | - Peter J Keir
- Department of Kinesiology, McMaster UniversityHamilton, Ontario, Canada
| | - Torben B Hansen
- Orthopaedic Research Unit, Regional Hospital HolstebroHolstebro, Denmark
| | - Glenn Pransky
- Liberty Mutual Research Institute for Safety71 Frankland Road, Hopkinton, Massachusetts, 01748
| | - Jia-Hua Lin
- Liberty Mutual Research Institute for Safety71 Frankland Road, Hopkinton, Massachusetts, 01748
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Abstract
The fingertip has an important role in bi-digital pinch quality, and pulp loss is common and difficult to solve. The pulp switch consists of a pulp island flap with a homodigital neurovascular pedicle, vascularized by the palmar digital artery of the non-dominant pulp transposed to the dominant pulp side. We report the results in 16 patients treated for loss of the dominant half of a digital pulp from January 2000 to December 2008. On review after a minimum of 6 (range 6-18) months, the Weber's test demonstrated an average of 8 mm in static 2 point discrimination test for all digits, except the ring finger. In the monofilament Semmes-Weinstein test, we obtained a score of 3.61 for the thumb and little fingers, and 4.31 for the other fingers. We did not find partial or total necrosis of the flap. The pulp switch flap gave satisfactory functional results for viability, sensitivity, and digital mobility providing a sensate bi-digital pinch with acceptable aesthetic results in a single surgical procedure.
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Affiliation(s)
- J Braga Silva
- Service of Hand Surgery and Reconstructive Microsurgery, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
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Nataraj R, Li ZM. Integration of marker and force data to compute three-dimensional joint moments of the thumb and index finger digits during pinch. Comput Methods Biomech Biomed Engin 2013; 18:592-606. [PMID: 23947659 DOI: 10.1080/10255842.2013.820722] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
This study presents methodology to determine joint moments of the digits of the hand during pinch function. This methodology incorporates steps to identify marker-based kinematic data defining aligned coordinate systems for individual digit segments and joint centre locations. The kinematic data are then transformed to a common reference frame along with the force data collected at pinch contact of a customised apparatus in three dimensions. These methods were demonstrated with a pilot investigation to examine the static joint moments occurring during two-digit oppositional precision pinch at a particular end point force level applied at the digit pads. Notable abduction joint moments at the proximal joints of both digits were observed, which implicate the role of respective intrinsic and extrinsic muscles in maintaining pinch grasp. Examining differences in joint moment results when substituting selected steps of this methodological approach suggested greater relative importance for joint centre identification and segment coordinate system alignment.
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Affiliation(s)
- Raviraj Nataraj
- a Departments of Biomedical Engineering , Orthopaedic Surgery, and Physical Medicine and Rehabilitation, Cleveland Clinic , Cleveland , OH , USA
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Abstract
A methodology was established to investigate the contact mechanics of the thumb and the index finger at the digit-object interface during precision pinch. Two force/torque transducers were incorporated into an apparatus designed to overcome the thickness of each transducer and provide a flexible pinch span for digit placement and force application. To demonstrate the utility of the device, five subjects completed a pinch task with the pulps of their thumb and index finger. Inter-digit force vector coordination was quantified by examining the 1) force vector component magnitudes, 2) resultant force vector magnitudes, 3) coordination angle - the angle formed by the resultant vectors of each digit, 4) direction angles - the angle formed by each vector and the coordinate axes, and 5) center of pressure locations. It was shown that the resultant force magnitude of the index finger exceeded that of the thumb by 0.8 ± 0.3 N and that the coordination angle between the digit resultant force vectors was 160.2 ± 4.6°. The experimental apparatus and analysis methods provide a valuable tool for the quantitative examination of biomechanics and motor control during dexterous manipulation.
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Affiliation(s)
- Tamara L Marquardt
- Hand Research Laboratory, Departments of Biomedical Engineering, OrthopaedicSurgery, and Physical Medicine and Rehabilitation, Cleveland Clinic, Cleveland, OH
| | - Zong-Ming Li
- Hand Research Laboratory, Departments of Biomedical Engineering, OrthopaedicSurgery, and Physical Medicine and Rehabilitation, Cleveland Clinic, Cleveland, OH
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Ziv E, Patish H, Dvir Z. Grip and pinch strength in healthy subjects and patients with primary osteoarthritis of the hand: a reproducibility study. Open Orthop J 2008; 2:86-90. [PMID: 19478930 PMCID: PMC2687110 DOI: 10.2174/1874325000802010086] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 04/07/2008] [Accepted: 04/22/2008] [Indexed: 11/22/2022] Open
Abstract
Grip, Key Pinch (KP), 3 Point Pinch (3PP) and 2 Point Pinch (2PP) strengths were measured twice weekly in 32 women with primary osteoarthritis of the hand (POAH) and 25 healthy women. Reproducibility was assessed by standard error of measurement (SEM) and the coefficient of variation (CV). Cutoff values for significant improvement or deterioration were determined and expressed, respectively, as either the smallest detectable difference (SDD) or critical difference (CD). The SDD and CD of grip and pinch strengths were higher in POAH patients than in the healthy group. Among the pinch tests the 2PP findings were least reproducible. The relatively high SDD and CD scores indicate that improvement may be detected only in patients with moderate to severe weakness of grip and pinch. Furthermore, in POAH patients, diagnosing strength changes using the 2PP test is invalid due to low reproducibility.
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Affiliation(s)
- Efrat Ziv
- Department of Occupational Therapy, Sackler Faculty of Medicine, Tel Aviv University
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Abstract
Myogenic differentiation is a highly orchestrated, multistep process that is coordinately regulated by growth factors and cell adhesion. We show here that integrin-linked kinase (ILK), an intracellular integrin- and PINCH-binding serine/threonine protein kinase, is an important regulator of myogenic differentiation. ILK is abundantly expressed in C2C12 myoblasts, both before and after induction of terminal myogenic differentiation. However, a noticeable amount of ILK in the Triton X-100-soluble cellular fractions is significantly reduced during terminal myogenic differentiation, suggesting that ILK is involved in cellular control of myogenic differentiation. To further investigate this, we have overexpressed the wild-type and mutant forms of ILK in C2C12 myoblasts. Overexpression of ILK in the myoblasts inhibited the expression of myogenic proteins (myogenin, MyoD, and myosin heavy chain) and the subsequent formation of multinucleated myotubes. Furthermore, mutations that eliminate either the PINCH-binding or the kinase activity of ILK abolished its ability to inhibit myogenic protein expression and allowed myotube formation. Although overexpression of the ILK mutants is permissive for the initiation of terminal myogenic differentiation, the myotubes derived from myoblasts overexpressing the ILK mutants frequently exhibited an abnormal morphology (giant myotubes containing clustered nuclei), suggesting that ILK functions not only in the initial decision making process, but also in later stages (fusion or maintaining myotube integrity) of myogenic differentiation. Additionally, we show that overexpression of ILK, but not that of the PINCH-binding defective or the kinase-deficient ILK mutants, prevents inactivation of MAP kinase, which is obligatory for the initiation of myogenic differentiation. Finally, inhibition of MAP kinase activation reversed the ILK-induced suppression of myogenic protein expression. Thus, ILK likely influences the initial decision making process of myogenic differentiation by regulation of MAP kinase activation.
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Affiliation(s)
- Yao Huang
- Department of Cell Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
- The Cell Adhesion and Matrix Research Center, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
| | - Ji Li
- Department of Cell Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
- The Cell Adhesion and Matrix Research Center, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
| | - Yongjun Zhang
- Department of Cell Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
- The Cell Adhesion and Matrix Research Center, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
| | - Chuanyue Wu
- Department of Cell Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
- The Cell Adhesion and Matrix Research Center, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
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