Classification of upper-limb dysfunction severity and prediction of independence in activities of daily living after cervical spinal-cord injury.

STUDY DESIGN: Prospective observational study. OBJECTIVES: Classification of spinal-cord injury and prediction of independence in activities of daily living (ADL) based on performance evaluations such as upper-limb function have not been reported. Therefore, this study aimed to establish a severity classification and calculate cutoff values for independence in ADL using the Capabilities of Upper Extremity Test (CUE-T) for individuals with cervical spinal-cord injury (CSCI). SETTING: A spinal-cord injury rehabilitation center in Japan. METHODS: This study included individuals with subacute CSCI. Collected data included the CUE-T and Spinal Cord Independence Measure III (SCIM III) scores. The severity classification was used for the hierarchical cluster analysis using the CUE-T. The cutoff values of CUE-T scores for independence in ADL were calculated using an adjustment model with logistic regression analysis. The dependent variable was binary (independent/non-independent) for each SCIM III Self-care item, and the independent variable was CUE-T. RESULTS: A total of 71 participants were included in the analysis. The severity of upper-limb dysfunction was classified into four categories using CUE-T. Significant differences in upper-limb function and ADL were observed between clusters. The cutoff values for CUE-T score for independence in ADL ranged from 37 to 91 points. All cutoff values showed good results in the internal validation, sensitivity analysis. CONCLUSIONS: This study determined the severity of upper limb function in CSCI and the cutoff values of CUE-T scores for independence in ADL. These results may help set criteria and goals for interventions in the clinical and research fields. SPONSORSHIP: None.

Movement analysis of the distal transverse arch of the dominant hand while grasping and pinching objects: A descriptive, correlational research study.

BACKGROUND: The distal transverse arches obtained from active and passive motions of the hand and the used range of motion (u-ROM) of the hand arch in activities of daily living have rarely been reported. PURPOSE: This study aimed to investigate the distal transverse arch angle of the dominant hand, the influence of age, and the u-ROM of the arch when grasping and pinching objects. STUDY DESIGN: Descriptive and correlational research design. METHODS: The active and passive distal transverse arches of the dominant hand of 104 healthy subjects were measured using a goniometer. Additionally, the hand arch was measured when the subjects grasped and pinched objects. These data were used to analyze the correlation with age and to calculate the u-ROM (u-ROM %) rate of the distal transversal arch. Furthermore, the u-ROM% between the ring and fifth finger components of the hand arch was compared. RESULTS: The active and passive dorsal arch angles were 135.8 (10.0°) and 169.9 (11.5°), respectively. The distal transverse arch angle tended to decline with age (active: r = -0.18, p = 0.07, 95% confidence interval = -0.36 to 0.02; passive: r = -0.40, p ≤ 0.001, 95% confidence interval = -0.55 to -0.23). The u-ROM% of the hand arch in grasping and pinching ranged from 65.5 (9.8)% to 84.6 (11.6)% and from 52.1 (7.9)% to 67.4 (9.1)%, respectively, against active and passive motions. The ring finger component was significantly higher than the fifth finger component (active: p = 0.08 to <0.001, effect size = -0.17 to -0.69; passive: p ≤ 0.001, effect size= -0.71 to -0.86). A similar trend was observed in both men and women. CONCLUSIONS: Therapists should evaluate the movement of the distal transverse arch of the injured hand in detail and consider the age, sex, and component of the hand arch when intervening.

Verification of the minimal clinically important difference of the Capabilities of Upper Extremity Test in patients with subacute spinal cord injury.

CONTEXT: The number of patients with cervical spinal cord injury (CSCI) is increasing, and the Capabilities of Upper Extremity Test (CUE-T) is recommended for introduction in clinical trials. We calculated the minimal clinically important difference (MCID) of the CUE-T using an adjustment model with an interval of 1 month. DESIGN: This was a prospective study. SETTING: This study was conducted with participants from the Chiba Rehabilitation Center in Japan. PARTICIPANTS: The participants were patients with subacute CSCI. INTERVENTIONS: The CUE-T and spinal cord independence measure (SCIM) III were performed twice within an interval of 1 month. OUTCOME MEASURES: The MCID was calculated using an adjustment model based on logistic regression analysis. The participants were classified into an improvement group and a non-improvement group based on the amount of change in the two evaluations using the 10-point SCIM III MCID as an anchor. RESULTS: There were 52 participants (56.8 ± 13.5 years old, 45 men/7 women) with complete or incomplete CSCI: 18 in the improvement group and 34 in the non-improvement group. A significant regression equation was obtained when calculating the MCID, and the total, hand, and side scores were 7.7, 2.0, and 3.7 points, respectively. CONCLUSION: The calculated MCID of the CUE-T in this study was 7.7 points. The results of this study provide useful criteria for implementation in clinical trials. Future studies should use patient-reported outcomes, a more recommended anchor, and calculate the MCID using methods such as the patient's condition.

Evaluation of hand functions and distal radioulnar joint instability in elite wheelchair basketball athletes: a cross-sectional pilot study.

BACKGROUND: Wrist injury affects wheelchair basketball players' performance; however, the relationship between distal radioulnar joint (DRUJ) instability and hand functions is unclear. This cross-sectional pilot study investigated DRUJ instability in elite female wheelchair basketball athletes using force-monitor ultrasonography. METHODS: Nine elite female wheelchair basketball athletes (18 wrists) were included in the study. A triangular fibrocartilage complex (TFCC) injury was confirmed using magnetic resonance imaging (MRI). Hand functions were evaluated based on the range of motion (ROM) of wrist palmar flexion, dorsiflexion, radial deviation, and ulnar deviation; grip strength; arm circumference; forearm circumference; and DRUJ instability or pain using the ballottement test. The Mann-Whitney U test was used to compare parameters between the TFCC-injured and intact wrists. Radioulnar displacement was measured using force-monitor ultrasonography and pressure data, and the displacement-to-force ratio was used as an indicator of DRUJ instability. The correlation between the DRUJ displacement-to-force ratio and each hand function assessment was evaluated using Pearson correlation coefficient for the TFCC-injured and intact wrists. A generalized linear mixed model (GLMM) was used to estimate the relationship between hand functions and DRUJ instability. RESULTS: TFCC injuries in seven wrists were confirmed using MRI findings (38.9%). The ulnar deviation ROM values of the TFCC-injured wrist (n = 7) and intact (n = 11) groups were 38.6 ± 8.0° and 48.6 ± 7.8°, respectively. The ulnar deviation ROM was significantly smaller in the TFCC-injured wrists (p = 0.02, r = - 0.54). In the TFCC-injured wrists, no correlation was observed between the displacement-to-force ratio and the hand function assessment. In contrast, the displacement-to-force ratio negatively correlated with grip strength, arm circumference, and forearm circumference in the intact wrists (Pearson correlation coefficient r = - 0.78, - 0.61, and - 0.74, respectively). The GLMM showed that the displacement-to-force ratio significantly affected grip strength, arm circumference, and forearm circumference in the intact group. CONCLUSIONS: In intact wrists, correlations were observed between hand functions such as upper arm/forearm strength and DRUJ stability evaluated using ultrasound. Maintaining and strengthening grip strength, forearm circumference, and arm circumference are associated with DRUJ stability and may be related to TFCC injury prevention in wheelchair basketball athletes. TRIAL REGISTRATION: The protocol was registered with the UMIN Clinical Trials Registry (UMIN000043343) [Date of first registration: 16/02/2021].

Application of force-monitor ultrasonography to assess distal radioulnar joint instability in patients with triangular fibrocartilage complex injury.

Introduction: In this study, we evaluated the differences and measurement accuracy in the force-displacement relationship of the distal radioulnar joint (DRUJ) between patients with triangular fibrocartilage complex (TFCC) injury and healthy controls using force-monitor ultrasonography. Methods: This study included 11 TFCC injury patients and 22 healthy controls. We evaluated differences in the force-displacement relationship of the DRUJ in these patients using force-monitor ultrasonography. Cyclic compression was applied to the dorsal surface of the ulnar head. Distance between the dorsal surface of the distal radius and ulnar head at the DRUJ level was measured in the initial and pressed-down positions. Changes in radioulnar displacement, applied force, and displacement-to-force ratio were measured. Furthermore, we compared the parameters between the affected and unaffected wrists and between TFCC injury patients and controls. Results: The radioulnar displacement and displacement-to-force ratio were significantly larger in the affected wrists than in the unaffected wrists (P = 0.003 and P = 0.02). The affected/unaffected side ratio of radioulnar displacement and displacement-to-force ratio were significantly larger in the TFCC injury patients than in the controls (P = 0.003 and P = 0.02). The area under the curve was 0.82 for the affected/unaffected ratio of the radioulnar displacement. The optimal cutoff value indicated by the receiver-operating characteristic curve for the affected/unaffected ratio of the radioulnar displacement was 1.71; the sensitivity and specificity were 82% and 86%, respectively. Conclusions: Assessing the DRUJ instability with force-monitor ultrasonography may help identify TFCC-injured wrists.

Quantitative assessment of the course of distal radioulnar joint instability.

Introduction: There is a lack of methods to objectively evaluate improvement in distal radioulnar joint (DRUJ) instability through treatment. We used ultrasonography to assess DRUJ instability and calculated the minimal detectable change (MDC) in healthy individuals. MDC was used to evaluate post-treatment changes in a patient with triangular fibrocartilage complex (TFCC) injury. Methods: DRUJ instability was evaluated using force-monitor ultrasonography in eight healthy male participants to determine MDC and in a man in his 60s who underwent surgery and rehabilitation for TFCC injury (Palmer classification: type 2C). In the patient, DRUJ instability was measured pre-operatively, 3 months postoperatively, and 1 year post-operatively. Self-reported hand and upper limb functional ability were also recorded. The transducer of the force-monitor ultrasonographic system was used to apply cyclic compressions to the wrists automatically and measure DRUJ displacements. The amount of displacement was calculated using the distance between the radius and ulna before and during cyclic compression to the wrists. The applied pressure was measured as the force to the wrist, and the displacement-to-force ratio was calculated. Results: The 95% confidence MDC95 for radioulnar displacement, displacement force, and displacement-to-force ratio were 0.27-0.31 mm, 0.30-0.59 N, and 0.12-0.15 mm/N, respectively. The patient's post-operative decrease in displacement exceeded the MDC95. DRUJ stability, pain, and use of the affected hand in daily life improved. Discussion: Force-monitor ultrasonography can quantitatively evaluate post-treatment improvement in DRUJ stability over time. MDC for DRUJ instability can assess recovery after treatment or rehabilitation and determine changes resulting from interventions.

Interaction of the Left-Right Somatosensory Pathways in Patients With Thalamic Hemorrhage: A Case Report.

Neural plasticity compensates for the loss of motor function after stroke. However, whether neural plasticity occurs in the somatosensory pathways after stroke is unknown. We investigated the left-right somatosensory interaction in two hemorrhagic patients using a paired somatosensory evoked potentials (p-SEPs) recorded at CP3 and CP4, which was defined as an amplitude difference between the SEPs of paired median nerve stimulations to both sides and that of single stimulation to the affected side. Patient 1 (61-year-old, left thalamic hemorrhage) has a moderate motor impairment, severe sensory deficit, and complained of pain in the affected right upper limb. Patient 2 (72-year-old, right thalamic hemorrhage) had slight motor and sensory impairments with no complaints of pain. Single SEPs (s-SEPs) were obtained by stimulation of the right and left median nerves, respectively. For paired stimulations, 1 ms after the first stimulation to the non-affected side, followed by a second stimulation to the affected side. In patient 1, a s-SEP with stimulation to the non-affected side and a p-SEP were observed in CP4. However, a s-SEP was not observed in either hemisphere with stimulation to the affected side. On the other hand, in patient 2, a s-SEP in CP3 with stimulation to the non-affected side and in CP4 with stimulation to the affected side were observed; however, a p-SEP was not observed. In addition, to investigate the mechanism by which ipsilateral median nerve stimulation enhances contralateral p-SEP in patient 1, we compared the SEP averaged over the first 250 epochs with the SEP averaged over the second 250 epochs (total number of epochs recorded: 500). The results showed that in the patient 1, when the bilateral median nerve was stimulated continuously, the habituation did not occur and the response was larger than that of the s-SEP with unilateral median nerve stimulation. In the current case report, the damage to the thalamus may cause neuroplasticity in terms of the left-right interaction (e.g., left and right S1). The somatosensory input from the affected side may interfere with the habituation of the contralateral somatosensory system and conversely increase the response.

Contralateral and Ipsilateral Interactions in the Somatosensory Pathway in Healthy Humans.

Hyper-adaptability, the ability to adapt to changes in the internal environment caused by neurological disorders, is necessary to recover from various disabilities, such as motor paralysis and sensory impairment. In the recovery from motor paralysis, the pre-existing neural pathway of the ipsilateral descending pathway, which is normally suppressed and preserved in the course of development, is activated to contribute to the motor control of the paretic limb. Conversely, in sensory pathways, it remains unclear whether there are compensatory pathways which are beneficial for the recovery of sensory impairment due to damaged unilateral somatosensory pathways, such as thalamic hemorrhage. Here, we investigated the interaction between the left and right somatosensory pathways in healthy humans using paired median nerve somatosensory evoked potentials (SEPs). Paired median nerve SEPs were recorded at CP3 and CP4 with a reference of Fz in the International 10-20 System. The paired median nerve stimulation with different interstimulus intervals (ISIs; 1, 2, 3, 5, 10, 20, 40, 60, and 100 ms) was performed to test the influence of the first stimulus (to the right median nerve) on the P14, P14/N20, and N20/P25 components induced by the second stimulus (left side). Results showed that the first stimulation had no effect on SEP amplitudes (P14, P14/N20, and N20/P25) evoked by the second stimulation in all ISI conditions, suggesting that there might not be a neural connectivity formed by a small number of synapses in the left-right interaction of the somatosensory pathway. Additionally, the somatosensory pathway may be less diverse in healthy participants.

Skeletal Muscle Mass and Higher-Level Functional Capacity in Female Community-Dwelling Older Adults.

PURPOSE: In this study, our purpose was to examine the relationship between skeletal muscle mass and higher-level functional capacity in female community-dwelling older adults. Participant(s) and Methods: In this cross-sectional study, we targeted 55 female community-dwelling older adults aged 65 years and above participating in long-term care prevention classes in Ibaraki Prefecture between 2018 and 2020. We excluded individuals with cognitive impairment and those judged as having sarcopenia. The variables of interest included age, height, weight, body mass index, skeletal muscle mass index (SMI), handgrip strength, step count, and family structure. We calculated the SMI by dividing the extremities' total lean mass by the square of the height (in m), while the number of steps was calculated using the three-axis accelerometer Actigraph GT3X®. We measured skeletal muscle mass via bioelectrical impedance analysis using the InBody270 body composition analyzer and muscular strength as grip strength. RESULTS: We observed significant relationships between skeletal muscle mass and Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) (ß = 0.336, p < 0.01) and handgrip strength (ß = 0.230). CONCLUSION: In this study, a relationship between skeletal muscle mass and higher-level functional capacity was demonstrated among elderly female community residents.

Assessment of distal radioulnar joint stability in healthy subjects: Changes with dominant hand, sex, and age.

This study aimed to elucidate the differences in distal radioulnar stability in dominant/nondominant hand, sex, and age. Bilateral wrists of 60 healthy subjects were evaluated using force-monitoring ultrasonography. This apparatus was developed to apply cyclic compression and measure applied force to displacement during an ultrasound exam. The transducer was placed on the dorsal side of the distal radioulnar joint, and the center of the ulnar head was displayed on the monitor. The distance between the dorsal surface of the distal radius and the ulnar head was measured at an initial and at a pressed-down position. The radioulnar displacement, applied force to displacement, and displacement-to-force ratio were evaluated. The results were compared between the dominant and nondominant hands, and between males and females, and among different age groups. There were no significant differences in the parameters between the dominant and nondominant hands. The applied force to displacement was significantly greater in the male group compared with the female group. There were significant effects for the different age groups in all parameters (displacement: F = 3.67, p = .008; applied-force: F = 3.08, p = .019; displacement-to-force ratio: F = 4.66, p = .002). Our results indicated that the stability of distal radioulnar joint differed depending on age and sex. Age and sex should be considered when assessing distal radioulnar joint stability.

Postoperative diagnostic potentials of median nerve strain and applied pressure measurement after carpal tunnel release.

BAKGROUND: The objective of this study is to investigate the prognostic values of median nerve strain and applied pressure measurement for the assessment of clinical recovery after carpal tunnel release. METHODS: Forty-five wrists, from 45 idiopathic carpal tunnel syndrome patients who treated with open carpal tunnel release, were evaluated by ultrasound. Median nerve strain, pressure applied to the skin, and ratio of pressure-strain were measured at the proximal part of the carpal tunnel. In addition, distal latencies in the motor and sensory nerve conductions studies and cross-sectional area of median nerve were measured. The parameters were compared before and after the open carpal tunnel release. According to patient recovery, the receiver operating characteristic curves were generated to evaluate the prognostic values of the parameters. The areas under the receiver operating characteristic curves were compared among parameters. RESULTS: There was a significant increase in the median nerve strain, and significant decreases in the pressure applied to the skin and ratio of pressure-strain after carpal tunnel release (P < 0.01). There were significant decreases in the distal latencies and the cross-sectional area after carpal tunnel release (P < 0.01). The areas under the curves were 0.689, 0.773, 0.811, 0.668, 0.637, and 0.562 for the pressure, strain, pressure-strain ratio, motor latency, sensory latency, and area, respectively. CONCLUSIONS: The results suggest that elasticity of the median nerve and pressure around the nerve recover quickly after carpal tunnel release. Pressure-strain ratio was the most reliable parameter to reflect clinical recovery. The measurement of strain and applied pressure can be useful indicators to evaluate effectiveness of the carpal tunnel release. TRIAL REGISTRATION: Registered as NCT04027998 at ClinicalTrials.gov. Retrospectively registered on July 22, 2019.

Quantitative assessment of distal radioulnar joint stability with pressure-monitor ultrasonography.

BACKGROUND: Diagnosing distal radioulnar joint (DRUJ) instability remains a challenge as it relies on physical examination. To quantitatively assess DRUJ stability, a pressure-monitor ultrasound system was developed. The objective of this study was to evaluate the force-displacement relationship of DRUJ in normal subjects. METHODS: Nine wrists of 9 asymptomatic volunteers were evaluated. The pressure-monitor ultrasound system was developed to apply pressure to the tissue with a pre-determined cycle and displacement of the transducer. Each subject was imaged sitting with the elbow flexed and forearm pronated. The dorsal surface of the distal radius and the center of the ulnar head were displayed at DRUJ level. The pressure toward palmar direction was applied to the distal ulna with different levels of transducer displacements, i.e., 1 mm, 2 mm, and 3 mm. The distance between the dorsal surface of the ulnar head and the dorsal surface of the distal radius was measured. The first measurement was performed at the initial position, and the second measurement was performed when the transducer pressed down the ulna to the degree that the ulnar head had shifted to the most palmar position. At the same time, the pressure to the transducer was measured. The changes of radioulnar distance (=the measurement at the most palmar position-the measurement at the initial position) and pressure, and pressure/distance ratio were compared among the different transducer displacements. RESULTS: The pressure was significantly increased as the transducer displacement became larger (P < 0.01). The changes of radioulnar distance were smaller in the 1 mm displacement condition compared to the 2 and 3 mm displacement conditions (P < 0.05). The pressure/distance ratio was larger in the 1 mm displacement condition compared to the 2 and 3 mm displacement conditions (P < 0.05). CONCLUSIONS: A method to assess DRUJ stability by measuring changes in radioulnar distance and force application was developed. It was found that the application of 2 mm displacement and 200 g force was the critical stress for the capsuloligamentous structures to start stabilizing DRUJ. This methodology and the indices may be clinically useful to investigate the mechanical properties of patients with DRUJ instability.

Reliability of Quantitative Assessment of Distal Radioulnar Joint Stability With Force-Monitor Ultrasonography.

The purpose of this study was to evaluate the reliability of ultrasound assessment of the displacement-force relationships for distal radioulnar joint (DRUJ) stability. Non-dominant wrists of 10 healthy male subjects were evaluated by force-monitor ultrasonography. This apparatus was developed to apply cyclic compression to the wrist with pre-determined transducer displacement conditions in the range of 0.1-3.0 mm. The subject's wrist was placed on the table with the forearm in the pronated position. The transducer was placed on the dorsal surface of the distal radius and ulna, perpendicular to the long axis of the forearm. The center of the ulnar head was at the DRUJ level. The distance between the dorsal surface of the distal radius and the ulnar head was measured at an initial and a pressed-down position. Changes in radioulnar displacement, force to the wrist and the displacement/force ratio were evaluated. The measurements were performed independently by two raters. The intra-class correlation coefficients (ICCs) for the radioulnar displacement were 0.76, 0.68, and 0.93, in the 1.0, 2.0, and 3.0 mm transducer displacement conditions, respectively. The ICCs for the force to the wrist were 0.18, 0.67, and 0.34, in different transducer displacement conditions, respectively. The ICCs for the displacement/force ratios were 0.68, 0.67, and 0.97, in different transducer displacement conditions, respectively. The highest ICC for the radioulnar displacement and the displacement/force ratio was observed in the 3.0 mm displacement condition. This assessment of displacement-force relationships may be useful to quantify DRUJ stability. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2053-2060, 2019.

Measurement of wrist flexion and extension torques in different forearm positions.

BACKGROUND: Forceful activities of the wrist were considered to be a risk factor for the epicondylitis. However, there are still conflicting evidence concerning work-relatedness of epicondylitis. The main problem is that there is little information about which forearm postures are capable of withstanding higher torque loads and the extent of the differences in the torques generated by different forearm postures. The objective of this study was to investigate the differences in wrist flexion and extension torques among different forearm positions in healthy subjects. METHODS: Twenty wrists of 10 asymptomatic volunteers were evaluated. The apparatus to measure the wrist torque consisted of a handle with a force sensor and a table to place the forearm in different positions. The direction of the handle can change when measuring different forearm positions. The forearm of the examinee was secured to the table. The participants were asked to exert themselves in maximal isometric contraction for wrist flexion or extension, and to maintain it for 5 s. Each evaluation of the flexion and extension torque was conducted twice. Three forearm positions were evaluated: neutral, pronation, and supination. The intra-class correlation coefficients between first and second measurements were evaluated for the maximum torque. The maximum torques and flexion/extension ratio were compared among the positions. In addition, the agility and endurance for the wrist extension/flexion torques were compared among the positions. RESULTS: The intra-class correlation coefficients between first and second measurements were 0.928 and 0.866 for the wrist flexion and extension measurements, respectively. The highest torques for the wrist flexion and extension were observed in the supination and pronation positions, respectively (P < 0.01). There was a higher extension/flexion ratio in the supination position compared to the other positions (P < 0.05). There was a superior agility for the wrist flexion in the supination position compared to the pronation position. CONCLUSIONS: The normal balance of the wrist flexion-extension torques in different forearm positions were characterized. This information might aid the provision of advice regarding the optimal positions for performing specific tasks and could help to elucidate the pathophysiology of epicondylitis.