Complications after hand surgery in patients with a raised International Normalized Ratio.

A multicentre database was used to compare complications in 231 patients with an elevated International Normalized Ratio with 1626 control patients with a normal International Normalized Ratio. Patients with International Normalized Ratios measured within 48 hours of hand surgery were identified. Logistic regression models were used to assess the association between anticoagulation and reoperation rates, emergency department visits and hospital readmissions for the first 30 days after operation. The group with a raised International Normalized Ratio had a significantly higher Charlson Comorbidity Score. An elevated International Normalized Ratio was associated with an odds ratio for a post-operative emergency department visit of 3.3 and an odds ratio of 4.7 for readmission. There was no statistically significant difference in early reoperations between the two groups. LEVEL OF EVIDENCE: III.

The quality of randomised controlled trials involving surgery from the hand to the elbow: a critical analysis of the literature.

AIMS: Our purpose was to determine the quality of current randomised controlled trials (RCTs) in hand surgery using standardised metrics. MATERIALS AND METHODS: Based on five-year mean impact factors, we selected the six journals that routinely publish studies of upper extremity surgery. Using a journal-specific search query, 62 RCTs met our inclusion criteria. Then three blinded reviewers used the Jadad and revised Coleman Methodology Score (RCMS) to assess the quality of the manuscripts. RESULTS: Based on the Jadad scale, 28 studies were of high quality and 34 were of low quality. Methodological deficiencies in poorly scoring trials included the absence of rate of enrolment, no power analysis, no description of withdrawal or dropout, and a failure to use validated outcomes assessments with an independent investigator. CONCLUSION: A large number of RCTs in hand, wrist, and elbow surgery were of suboptimal quality when judged against the RCMS and Jadad scales. Even with a high level of evidence, study design and execution of RCTs should be critically assessed. Methodological deficiencies may introduce bias and lead to statistically underpowered studies. Cite this article: Bone Joint J 2017;99-B:94-9.

A knotless bidirectional-barbed tendon repair is inferior to conventional 4-strand repairs in cyclic loading.

UNLABELLED: We divided 21 flexor digitorum profundus tendons in the index, middle and ring fingers in seven cadaver hands into three groups. The tendons were cut in zone 2 and repaired using a 4-strand cruciate core suture repair with one of the following three materials in each group: (1) a knotless repair with a 2-0 bidirectional-barbed suture, which has similar tensile strength as a 4-0 non-barbed suture used in the other two groups; (2) a knotted locking repair with a non-barbed 4-0 conventional suture; and (3) a non-locking repair with a non-barbed 4-0 knotless suture. The repaired fingers were cyclically loaded through a simulated active range of motion to a 5 N load. We monitored and recorded the gap sizes at regular intervals during the test. The 2-0 bidirectional-barbed suture group and non-barbed suture groups developed gaps of 2.2 mm after 10 cycles and 2.4 mm after 20 cycles, respectively. Over 1000 cycles, the mean gaps were 3.2 mm in the 4-0 conventional suture group and 9.1 mm in the 2-0 bidirectional-barbed group. The tendons in the 2-0 bidirectional-barbed group gapped earlier, with statistically significant differences compared with those in the locking repair with a non-barbed 4-0 knotless suture group. The repair strength of the barbed suture technique was inferior to the cruciate repairs using a conventional 4-0 non-barbed suture tested in this cyclic-loading model. LEVEL OF EVIDENCE: Level V.

Evaluation of pisotriquetral motion pattern using four-dimensional CT: initial clinical experience in asymptomatic wrists.

AIM: To characterise the normal motion pattern of the pisotriquetral (PT) joint during wrist extension and flexion, as well as observer performance of measurements using four-dimensional (4D)-computed tomography (CT) acquisitions and double-oblique multiplanar reconstruction (MPR) technique in asymptomatic contralateral joints of patients with unilateral wrist pain. MATERIALS AND METHODS: In this Health Insurance Portability and Accountability Act (HIPAA)-compliant institutional review board-approved study, 4D-CT was performed on the asymptomatic contralateral wrists of 10 patients (mean age: 46 years; M/F: 6/4) for comparison to the symptomatic side. Two independent observers defined the "oblique-sagittal" plane for PT joint measurements. Measurements were obtained for the anteroposterior (AP) interval and craniocaudal (CC) excursion during the extension-flexion arc of wrist motion. RESULTS: The median (interquartile range) of the AP interval was 0.65 mm (0.55-1 mm) in extension, 1.1 mm (0.8-1.82 mm) in the neutral position, and 4.65 mm (2.07-5.87 mm) in flexion. Likewise, the median of the CC excursions in asymptomatic wrists were 0 mm in extension, 0.27 mm (0-0.37 mm) in the neutral position, and 0.28 mm (0.18-0.31 mm) in flexion. The AP interval measurements obtained at wrist flexion were larger than measurements obtained at wrist extension. There was a strong consistency in AP interval difference measurements between the two observers (ICC=0.80; p<0.01); however, CC excursion difference measurements did not reach the significance threshold between the two observers (ICC=0.40; p=0.11). CONCLUSION: PT joint kinematics in asymptomatic wrists demonstrates an increase in AP interval and CC excursion during wrist flexion. MPR techniques provide good interobserver agreements for AP interval measurements. The reported intervals for asymptomatic joints can be used as a reference for asymptomatic wrists.

Comparison of digital nerve sensory recovery after repair using loupe or operating microscope magnification.

UNLABELLED: Our purpose was to determine whether there was a significant difference in sensory recovery after digital nerve repair using loupe magnification or an operating microscope. We identified patients aged 21-75 who had primary proper digital nerve repairs at least 24 months before our study. A total of 12 patients with 13 digital nerve injuries repaired with loupe magnification and nine patients with 12 digital nerve injuries repaired using the operating microscope, agreed to return for assessment by a therapist blinded to treatment. We found no significant difference in sensory recovery between the two groups as measured by static two-point discrimination, moving two-point discrimination, and Semmes-Weinstein monofilament. There were also no significant differences in average Disabilities of the Arm Shoulder and Hand or visual analogue pain scores. LEVEL OF EVIDENCE: IV.

Long-term outcomes following single-portal endoscopic carpal tunnel release.

BACKGROUND: There is limited published information about long-term outcomes and recurrence rates following single-portal endoscopic carpal tunnel release. METHODS: We reviewed symptom and function outcomes from a prospectively collected database of patients who underwent single-portal endoscopic carpal tunnel release at a minimum of 8 years follow-up. Out of 207 patients in the original database, we were able to confirm correct current contact information for 106 patients. Of these, 91 patients with 115 single-portal endoscopic carpal tunnel releases agreed to participate. All of these patients were eligible for this long-term follow-up study based on documented preoperative and 6-month postoperative Levine-Katz questionnaire scores. Patients then completed a current update of the Levine-Katz questionnaires to assess function and symptom outcomes at latest follow-up. RESULTS: The average 6-month postoperative scores were significantly lower compared with the average preoperative scores and were maintained at long-term follow-up. There were no significant differences in average change in scores at long-term follow-up compared to 6-months postoperative. CONCLUSIONS: Single-portal endoscopic carpal tunnel release is an effective surgical treatment for carpal tunnel syndrome. Low recurrence rates and maintenance of low symptom and function scores can be expected at 8 to 10 years following this technique.

Peripheral Quantitative CT (pQCT) Using a Dedicated Extremity Cone-Beam CT Scanner.

PURPOSE: We describe the initial assessment of the peripheral quantitative CT (pQCT) imaging capabilities of a cone-beam CT (CBCT) scanner dedicated to musculoskeletal extremity imaging. The aim is to accurately measure and quantify bone and joint morphology using information automatically acquired with each CBCT scan, thereby reducing the need for a separate pQCT exam. METHODS: A prototype CBCT scanner providing isotropic, sub-millimeter spatial resolution and soft-tissue contrast resolution comparable or superior to standard multi-detector CT (MDCT) has been developed for extremity imaging, including the capability for weight-bearing exams and multi-mode (radiography, fluoroscopy, and volumetric) imaging. Assessment of pQCT performance included measurement of bone mineral density (BMD), morphometric parameters of subchondral bone architecture, and joint space analysis. Measurements employed phantoms, cadavers, and patients from an ongoing pilot study imaged with the CBCT prototype (at various acquisition, calibration, and reconstruction techniques) in comparison to MDCT (using pQCT protocols for analysis of BMD) and micro-CT (for analysis of subchondral morphometry). RESULTS: The CBCT extremity scanner yielded BMD measurement within ±2-3% error in both phantom studies and cadaver extremity specimens. Subchondral bone architecture (bone volume fraction, trabecular thickness, degree of anisotropy, and structure model index) exhibited good correlation with gold standard micro-CT (error ~5%), surpassing the conventional limitations of spatial resolution in clinical MDCT scanners. Joint space analysis demonstrated the potential for sensitive 3D joint space mapping beyond that of qualitative radiographic scores in application to non-weight-bearing versus weight-bearing lower extremities and assessment of phalangeal joint space integrity in the upper extremities. CONCLUSION: The CBCT extremity scanner demonstrated promising initial results in accurate pQCT analysis from images acquired with each CBCT scan. Future studies will include improved x-ray scatter correction and image reconstruction techniques to further improve accuracy and to correlate pQCT metrics with known pathology.

Carpal tunnel volume changes of the wrist under distraction.

This study attempts to determine changes in carpal canal volume with distraction across the wrist. Uniform longitudinal distraction was maintained with two external fixators on the radial and ulnar aspects of the forearm axis of five cadaver specimens. After CT scanning, volume determinations were made at 5 mm increments beginning at the lunocapitate joint to a point 1.5 cm distal to the middle finger carpometacarpal joint. There was a statistically significant decrease of the mean total carpal canal volume from 0 to 4.54 kg of distraction, with no statistically significant decrease from 0 to 2.27 kg or 2.27 to 4.54 kg. The largest decrease occurred at 15 and 20 mm distal to the proximal edge of the transverse carpal ligament corresponding to the level of the hamate hook. Reduction in mean carpal canal volume was 10.2% and 7.5% at these distances, respectively, from 0 to 4.54 kg of distraction. Progressive distraction across the wrist causes a decrease in total carpal canal volume.

Dynamic performance of the mechanism of an automatically deployable ROPS.

The mechanism for an automatically deployable ROPS (AutoROPS) has been designed and tested. This mechanism is part of an innovative project to provide passive protection against rollover fatality to operators of new tractors used in both low-clearance and unrestricted-clearance tasks. The device is a spring-action, telescoping structure that releases on signal to pyrotechnic squibs that actuate release pins. Upper post motion begins when the release pins clear an internal piston. The structure extends until the piston impacts an elastomeric ring and latches at the top position. In lab tests the two-post structure consistently deployed in less than 0.3 s and latched securely. Static load tests of the telescoping structure and field upset tests of the fully functional AutoROPS have been successfully completed.

Static load test performance of a telescoping structure for an automatically deployable ROPS.

The automatically deployable ROPS was developed as part of an innovative project to provide passive protection against overturn fatality to operators of new tractors used in both low-clearance and unrestricted-clearance tasks. The primary objective of this phase of the research was to build a telescoping structure that would prove that a ROPS can be built that will (1) reliably deploy on signal, (2) rise in a sufficiently short amount of time, (3) firmly latch in its deployed position, and (4) satisfy SAE J2194 testing requirements. The two-post structure had previously been found to meet deployment time criteria, and design analyses indicated that neither the slip-fit joint nor the latch pins would fail at test loading. Four directions of static loading were applied to the structure to satisfy SAE requirements. For the series of static loading tests, the raised structure was found to maintain a protective clearance zone after all loads were applied. The structure is overly stiff and should be redesigned to increase its ability to absorb ground-impact energy. Results of dynamic tests and field upset tests are reported in companion articles. The next phase of development is to optimize the structure so that it will plastically deform and absorb energy that would otherwise be transferred to the tractor chassis.

Balance, mobility, and falls among elderly African American women.

OBJECTIVE: To compare balance, mobility, recent falls, and injuries among elderly African American and white women. DESIGN: This was a nonexperimental study. Participants, who were older than 65 yr of age, able to walk at least 30 ft, not residing in a nursing home, and with no acute medical problems, were recruited from 17 senior citizens' community centers. RESULTS: Compared with white women (n=180), African American women (n = 118) took fewer medications, had greater body mass indexes, had less muscle strength, and had more medical conditions and neurologic abnormalities. Additionally, these women were less active and had poorer performances on an obstacle course. The two groups had a similar histories of falls and injuries. For both groups, activity level and neurologic findings were predictors of obstacle course performance. For white women, muscle strength was an additional predictor of obstacle course performance. An additional predictor for African American women was range of motion. CONCLUSION: The poorer balance and mobility of African American women compared with white women may have consequences such as their functional dependence, resulting in their greater use of hospitals and formal and informal health services.

Modifying a functional obstacle course to test balance and mobility in the community.

A previously reported functional obstacle course (FOC) developed to assess elderly persons with and without balance and mobility impairment was used in a hospital-based study of 237 participants. A new modified version of the FOC was developed for use in a community-based study, by placing some obstacles next to walls instead of between parallel bars. These modifications eliminate the need for parallel bars or for extra personnel to interchange the obstacles. We were concerned that the modifications could affect performance scores, because touching or holding onto the now eliminated parallel bars could influence FOC scores under the original scoring system. To determine the effect of these modifications on FOC performance, we tested 36 volunteers, (18 fallers [falls within last year] and 18 non-fallers), on the modified parts of the old and new versions of the FOC. Random testing order and inter-trial rests were used. For both the old and new FOC versions, we summed quality and task completion time scores from the six modified obstacles (artificial turf, carpet, pine bark, sand, up ramp and down ramp) to create scores for quality and time. Our hypothesis was that there would be no performance difference between the original and modified obstacle course. Using a two-factor repeated-measures analysis of variance, we found no difference in quality scores between the two FOC versions and no effect of an interaction between faller status and the course versions. We did find that the time was approximately 2 seconds longer for the new version; however, the time increase was the same for fallers and non-fallers. These data show that fallers and non-fallers have comparable performance on both versions of the FOC; however, to compare the two obstacle courses we recommend an adjustment of 2 seconds in time scores. The obstacle course modifications will facilitate more extensive and efficient use of the obstacle course as a research tool to assess balance and mobility.

Finite element modeling of ROPS in static testing and rear overturns.

Even with the technological advances of the last several decades, agricultural production remains one of the most hazardous occupations in the United States. Death due to tractor rollover is a prime contributor to this hazard. Standards for rollover protective structures (ROPS) performance and certification have been developed by groups such as the Society of Automotive Engineers (SAE) and the American Society of Agricultural Engineers (ASAE) to combat these problems. The current ROPS certification standard, SAE J2194, requires either a dynamic or static testing sequence or both. Although some ROPS manufacturers perform both the dynamic and static phases of SAE J2194 testing, it is possible for a ROPS to be certified for field operation using static testing alone. This research compared ROPS deformation response from a simulated SAE J2194 static loading sequence to ROPS deformation response as a result of a simulated rearward tractor rollover. Finite element analysis techniques for plastic deformation were used to simulate both the static and dynamic rear rollover scenarios. Stress results from the rear rollover model were compared to results from simulated static testing per SAE J2194. Maximum stress values from simulated rear rollovers exceeded maximum stress values recorded during simulated static testing for half of the elements comprising the uprights. In the worst case, the static model underpredicts dynamic model results by approximately 7%. In the best case, the static model overpredicts dynamic model results by approximately 32%. These results suggest the need for additional experimental work to characterize ROPS stress levels during staged overturns and during testing according to the SAE standard.

Obstacle course performance and risk of falling in community-dwelling elderly persons.

OBJECTIVE: To determine the efficacy of obstacle course performance scores in predicting persons at risk for falls, after adjusting for age, sociodemographic, health-status, and physiologic variables. DESIGN: Correlational descriptive study design utilizing a logistic regression model. SETTING: Community setting. PATIENTS OR PARTICIPANTS: A convenience sample of 352 community-dwelling elderly individuals at sites in a metropolitan area. MAIN CRITERION MEASURE: Number of falls reported prospectively during a 2-year follow-up period. RESULTS: Obstacle course performance, fall history, symptoms of balance dysfunction, and activity level distinguished those who fell and those who did not 12 and 18 months later. At 24 months, range of motion and number of medications also were significant. In multivariate logistic regression, only history of a fall was a significant predictor of future falling at 12 and 18 months; at 24 months, the presence of balance dysfunction symptoms was the significant predictor of those who fell. CONCLUSIONS: The obstacle course, as a predictor of future falls, is not superior to the question of whether or not an individual has fallen in the previous year, and is not recommended to predict future falls. The obstacle course may be better as a short-term indicator of response to a rehabilitation program for balance and mobility.

Comparison of a functional obstacle course with an index of clinical gait and balance and postural sway.

BACKGROUND: Older adults commonly experience falls because of balance and mobility problems. Better assessment methods are needed to understand and correct balance and mobility disorders. METHODS: We used a low technology, functional obstacle course (FOC) to measure balance and mobility in 352 community-dwelling elderly participants. To establish concurrent validity of the FOC, we compared performance on the FOC with two established measures of balance and mobility: performance on the Tinetti Index (TI) and postural sway area measured on a force platform. RESULTS: Bivariate correlation analyses revealed significant inverse correlations between FOC completion time, the TI balance and gait subscores, and the TI total score (r = -.73 to -.78). The FOC quality scores and TI balance and subscores gait and TI total scores (r = .76 to .82) were significantly positively correlated. FOC time had significant, but small, positive correlations with sway area with eyes open (r = .18) and closed (r = .17) and nonsignificant correlation with sway area with visual feedback. FOC quality also had significant, but smaller, inverse correlations with sway area with eyes open (r = -.024) and closed (r = -.015), and nonsignificant correlation with sway area with visual feedback. Regression analysis showed that TI gait and balance measures accounted for most of the variance found in FOC performance. CONCLUSIONS: Our findings support the position that the FOC and the TI measure dynamic balance, whereas postural sway measures a different aspect of balance. Advantages of the FOC include the evaluation of environmentally influenced falls and balance problems.

Dynamometer for rat plantar flexor muscles in vivo.

A dynamometer is designed and fabricated to measure the force output during static and dynamic muscle actions of the plantar flexor muscles of anaesthetised rats in vivo. The design is based on a computer-controlled DC servomotor capable of angular velocities in excess of 17.5 rad s-1. The system controls the range of motion, angular velocity and electrical stimulation of the muscles, while monitoring the force output at the plantar surface of the foot. The force output is measured by a piezo-electric load cell that is rated at 5 kg capacity. Angular velocity and position are measured by a DC tachometer and potentiometer, respectively. All measurement devices are linear (r2 = 0.9998). The design minimises inertial loading during high-speed angular motions, with a variation in force output of less than 0.2%. The dynamometer proves to be an accurate and reliable system for quantifying static and dynamic forces of rat plantar flexor muscles in vivo.

Rehabilitation of elderly fallers: pilot study of a low to moderate intensity exercise program.

OBJECTIVE: The role of exercise in the prevention of falls and fall-related injuries among elderly persons is unclear. The objective of this study was to assess the response to an exercise-based rehabilitation program intended to improve balance and mobility and reduce or prevent falls. DESIGN: Pretest-posttest experimental design with repeated measures at baseline, immediately postintervention, and 6 months postintervention. To assess the effect of repeated exposure to our main outcome measure (the obstacle course), half of the participants (randomly selected) were allowed to practice on the obstacle course. SETTING: A veterans affairs medical center. PARTICIPANTS: Elderly, ambulatory, community-dwelling volunteers recruited from among local outpatients at our medical center. INTERVENTION: Sixty-five volunteers completed a 6-week supervised low to moderate intensity program of stretching, postural control, endurance walking, and coordination exercises designed to improve balance and mobility. Participants were divided into 2 groups: 34 participants who did not practice on the obstacle course during their exercise program and 31 participants who practiced on the obstacle course in addition to their otherwise identical exercise program. MAIN OUTCOME MEASURES: Performance on a functionally oriented obstacle course and self-reported falls and fall-related injuries. RESULTS: No significant performance differences were found between the two groups. After intervention, mean qualitative obstacle course scores improved modestly (5%) and mean obstacle course completion time decreased by 15% from baseline. These postintervention pairwise performance differences were clinically important but not statistically significant. Relative to baseline levels, postintervention falls and injuries did not change significantly. CONCLUSIONS: Our exercise intervention may have the potential to improve functional performance. However, some modifications are necessary to enhance efficacy. The obstacle course may be a useful tool in the evaluation of elderly persons with balance and mobility impairment in the rehabilitation setting.

The obstacle course: a tool for the assessment of functional balance and mobility in the elderly.

Many conventional methods employed in the assessment of balance and mobility in the elderly are expensive, difficult to administer, rely heavily on complex technology, or provide limited functional information so essential to the planning and implementation of rehabilitation interventions. The author has developed a functionally oriented obstacle course for use in the rehabilitation setting, to aid in the evaluation of elderly subjects with balance and mobility dysfunction. The obstacle course consists of 12 simulated functional tasks. Qualitative and quantitative individual task and overall scores are given for each obstacle course performance. A description of the design and rationale for the obstacle course is presented. For demonstration purposes, nonexperimental obstacle course performance data from a small group of elderly volunteers is included. With further validation studies, the obstacle course has potential to become a useful tool in the evaluation and rehabilitation of balance and mobility disorders, in order to aid in the prevention of falls and fall-related injuries in the elderly.