Normal Wrist Research Articles

Effect of grip type, wrist motion, and resistance level on pressures within the carpal tunnel of normal wrists

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. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Musculoskeletal Ultrasound Objective Structured Clinical Examination: An Assessment of the Test

To determine the reliability and validity of an objective structured clinical examination (OSCE) for musculoskeletal ultrasound (MSUS). A 9-station OSCE was administered to 35 rheumatology fellows trained in MSUS and to 3 expert faculty (controls). Participants were unaware of joint health (5 diseased/4 healthy). Faculty assessors (n = 9) graded image quality with predefined checklists and a 0-5 global rating, blinded to who performed the study. Interrater reliability, correlation between a written multiple choice question examination (MCQ) and OSCE performance, and comparison of fellow OSCE results with those of the faculty were measured to determine OSCE reliability, concurrent validity, and construct validity. Assessors' interrater reliability was good (intraclass correlation coefficient [ICC] 0.7). Score reliability was good in the normal wrist and ankle stations (ICC 0.7) and moderate in the abnormal wrist and ankle stations (ICC 0.4). MCQ grades significantly correlated with OSCE grades (r = 0.52, P < 0.01). The fellows in the bottom quartile of the MCQ scored 3.07 on the OSCE, significantly worse than the top quartile fellows (3.32) and the faculty (3.29; P < 0.01). Scores also significantly discriminated bottom quartile fellows from faculty in the normal wrist and ankle stations (3.38 versus 3.78; P < 0.01), but not in the abnormal stations (3.37 versus 3.49; P = 0.08). MSUS OSCE is a reliable and valid method for evaluation of MSUS skill. Normal joint assessment stations are more reliable than abnormal joint assessment stations and better discriminate poorly performing fellows from faculty. Therefore, MSUS OSCE with normal joints can be used for the assessment of MSUS skill competency.

Transverse Ultrasound Assessment of Median Nerve Deformation and Displacement in the Human Carpal Tunnel during Wrist Movements

The symptoms of carpal tunnel syndrome, a compression neuropathy of the median nerve at the wrist, are aggravated by wrist motion, but the effect of these motions on median nerve motion are unknown. To better understand the biomechanics of the abnormal nerve, it is first necessary to understand normal nerve movement. The purpose of this study was to evaluate the deformation and displacement of the normal median nerve at the proximal carpal tunnel level on transverse ultrasound images during different wrist movements, to have a baseline for comparison with abnormal movements. Dynamic ultrasound images of both wrists of 10 asymptomatic volunteers were obtained during wrist maximal flexion, extension and ulnar deviation. To simplify the analysis, the initial and final shape and position of the median nerve were measured and analyzed. The circularity of the median nerve was significantly increased and the aspect ratio and perimeter were significantly decreased in the final image compared with the first image during wrist flexion with finger extension, wrist flexion with finger flexion and wrist ulnar deviation with finger extension (p < 0.01). There were significant differences in median nerve displacement vector between finger flexion, wrist flexion with finger extension and wrist ulnar deviation with finger extension (all p's < 0.001). The mean amplitudes of median nerve motion in wrist flexion with finger extension (2.36 ± 0.79 normalized units [NU]), wrist flexion with finger flexion (2.46 ± 0.84 NU) and wrist ulnar deviation with finger extension (2.86 ± 0.51 NU) were higher than those in finger flexion (0.82 ± 0.33 NU), wrist extension with finger extension (0.77 ± 0.46 NU) and wrist extension with finger flexion (0.81 ± 0.58 NU) (p < 0.0001). In the normal carpal tunnel, wrist flexion and ulnar deviation could induce significant transverse displacement and deformation of the median nerve.

The Perfused, Pulseless Supracondylar Humeral Fracture: Intermediate-Term Follow-up of Vascular Status and Function

This study provides intermediate-term follow-up data on the vascular status of a cohort of children with a perfused, pulseless supracondylar humeral fracture who were managed with closed reduction, percutaneous pinning, and observation. Pediatric patients who sustained a perfused, pulseless supracondylar humeral fracture in the period from 2007 to 2011 and who had at least six months of clinical follow-up were identified and returned for evaluation. The primary outcome was vascular status as indicated by palpation of the radial pulse, the wrist brachial index, and arterial patency on duplex ultrasound. Secondary outcomes included functional parameters assessed with the Pediatric Outcomes Data Collection Instrument (PODCI), arm circumference, arm length, elbow motion, neurologic findings, muscle endurance, grip strength, and intolerance to cold. Follow-up data were obtained for twenty of thirty-six patients with a Gartland type-III fracture who had been managed with closed reduction and percutaneous pinning. Five patients had a return of a palpable pulse in the operating room after closed reduction and percutaneous pinning. All twenty had a palpable radial pulse at the time of the latest follow-up, and all nerve palsies resolved. Duplex ultrasound performed at the time of follow-up showed that fourteen patients had a patent brachial artery, five had brachial artery occlusion with large collateral vessels, and one had severe arterial stenosis. All fourteen patients with a patent brachial artery, two of the five with an occluded brachial artery, and the patient with a stenotic brachial artery had a normal wrist brachial index. Three patients with an occluded brachial artery had an abnormal wrist brachial index (0.73, 0.71, and 0.80). No differences between the injured and uninjured sides were observed with regard to arm circumference, arm length, elbow motion, muscle endurance, or grip strength. Thirteen of the twenty patients had higher functioning in all domains of the PODCI questionnaire compared with the general population. Two patients (one with an occluded artery and one with a patent artery) had lower values on the global functioning score. After an average of twenty months of follow-up, children with a perfused, pulseless supracondylar humeral fracture that had been treated with closed reduction, percutaneous pinning, and observation demonstrated a palpable distal radial pulse, normal growth of the arm, and good/excellent functional outcomes, although five of the twenty patients had an occluded brachial artery. Therapeutic level IV. See Instructions for Authors for a complete description of levels of evidence.

Contact areas of the scaphoid and lunate with the distal radius in neutral and extension: correlation of falling strategies and distal radial anatomy

The functional neutral of wrist movement is about 10° extension yet the distal radius has a volar tilt. This has not previously been explained. Assuming that the contact area between the carpus and the distal radius increased in wrist extension this would also help stabilize the carpus on the distal radius in positions where typically there is greater loading. To test this hypothesis we reconstructed three-dimensional structures of the carpal bones and distal radius using computed tomography scans of 13 normal wrists. The contact areas of the scaphoid with the distal radius were measured and were found progressively increased from flexion 20°, neutral, extension 20°, to extension 40°. The maximal increases in the contact area of the scaphoid and the distal radius was at full wrist extension. No significant changes in the contact areas of the lunate with the distal radius were found between the different positions. The contact characteristics provide greater stability to the carpus on the distal radius, and to help spread forces from impact to the wrist reducing the transmitted peak forces and thus the risk of distal radius and carpal injuries.

적외선카메라를 이용한 다트던지기 운동에서의 제한된 손목관절 움직임 분석

Abstract: Wrist joints consist of irregularly shaped carpal bones and other complicated structures. Thus, evaluatingthe motion of a wrist joint is a challenging task. In this study, we used an infrared camera to perform a kinematicanalysis of a dart-throwing motion. We measured the difference between the movement of a normal wrist and con-strained wrist (wrist with a wrist glove) in the dart-throwing motion with thirty six healthy participants. We measuredthe ulna flexion - radial extension motion using the attached passive marker and analyzed it using Polygon softwareand SPSS. The pitch and yaw motions with a glove was bigger than the ones without a glove by 20 and 15 degrees,respectively. On the other hand, the roll motion without a glove was bigger than the one with a glove by 7 degree.Wilcoxon signed rank test (p < 0.05) confirmed that there are significant differences between the motion with andwithout a glove. It was found that the magnitude of the pitch and yaw motion with a constrained wrist joint towardradial extension in dart-throwing motion is smaller than the one with a normal wrist joint. However, a normal wristjoint showed a bigger movement in the roll direction.Key words: Wrist joint, Dart -throwing motion, Infrared camera

Effectiveness of surgical reconstruction to restore radiocarpal joint mechanics after scapholunate ligament injury: An in vivo modeling study

Disruption of the scapholunate ligament can cause a loss of normal scapholunate mechanics and eventually lead to osteoarthritis. Surgical reconstruction attempts to restore scapholunate relationship show improvement in functional outcomes, but postoperative effectiveness in restoring normal radiocarpal mechanics still remains a question. The objective of this study was to investigate the benefits of surgical repair by observing changes in contact mechanics on the cartilage surface before and after surgical treatment. Six patients with unilateral scapholunate dissociation were enrolled in the study, and displacement driven magnetic resonance image-based surface contact modeling was used to investigate normal, injured and postoperative radiocarpal mechanics. Model geometry was acquired from images of wrists taken in a relaxed position. Kinematics were acquired from image registration between the relaxed images, and images taken during functional loading. Results showed a trend for increase in radiocarpal contact parameters with injury. Peak and mean contact pressures significantly decreased after surgery in the radiolunate articulation and there were no significant differences between normal and postoperative wrists. Results indicated that surgical repair improves contact mechanics after injury and that contact mechanics can be surgically restored to be similar to normal. This study provides novel contact mechanics data on the effects of surgical repair after scapholunate ligament injury. With further work, it may be possible to more effectively differentiate between treatments and degenerative changes based on in vivo contact mechanics data.

Scapholunate ligament injury adversely alters in vivo wrist joint mechanics: An MRI‐based modeling study

We investigated the effects of scapholunate ligament injury on in vivo radiocarpal joint mechanics using image-based surface contact modeling. Magnetic resonance images of 10 injured and contralateral normal wrists were acquired at high resolution (hand relaxed) and during functional grasp. Three-dimensional surface models of the radioscaphoid and radiolunate articulations were constructed from the relaxed images, and image registration between the relaxed and grasp images provided kinematics. The displacement driven models were implemented in contact modeling software. Contact parameters were determined from interpenetration of interacting bodies and a linear contact rule. Peak and mean contact pressures, contact forces and contact areas were compared between the normal and injured wrists. Also measured were effective (direct) contact areas and intercentroid distances from the grasp images. Means of the model contact areas were within 10 mm(2) of the direct contact areas for both articulations. With injury, all contact parameters significantly increased in the radioscaphoid articulation, while only peak contact pressure and contact force significantly increased in the radiolunate articulation. Intercentroid distances also increased significantly with injury. This study provides novel in vivo contact mechanics data from scapholunate ligament injury and confirms detrimental alterations as a result of injury.

Dart-throwing motion in patients with scapholunate instability: a dynamic four-dimensional computed tomography study

When the normal wrist rotates along the 'dart-throwing' plane, the proximal row remains still, with most motion occurring at the midcarpal joint. Whether this behaviour is maintained when the scapholunate ligaments are torn is not known. If this is the case, patients having a scapholunate ligament repair could benefit from early dart-throwing exercises without the risk of pulling the sutures apart. Using dynamic computer tomography, we analysed the carpal behaviour of six normal wrists and six wrists with scapholunate instability during dart-throwing motion. In the normal wrists, the scaphoid and lunate did not flex or extend, but translated along the frontal plane an average 5.9 and 5.6 mm, respectively. When the scapholunate ligaments were torn, the scaphoid shifted towards the radial styloid considerably more than the lunate (12.8 mm versus 4.8 mm; p = 0.005), inducing a scapholunate gap. Based on these findings, we cannot recommend dart-throwing exercises after scapholunate ligament repair, unless the joint is stabilized with wires or screws.

Correlation Between Subclinical Median Neuropathy and the Cross-Sectional Area of the Median Nerve at the Wrist

Although subclinical median neuropathy is not uncommon, its correlation with sonographic changes to the median nerve at the wrist has not been studied. We included 62 subjects (with 107 wrists) who reported experiencing no hand numbness. All subjects underwent nerve conduction studies (NCS) and sonography for median nerve at the pisiform level. The cross-sectional area (CSA), perimeter, long axis and short axis of median nerve were obtained off-line by manual tracing with a mouse and computed by one algorithm written in MatLab. Eighteen wrists met the inclusion criteria of subclinical median neuropathy. The CSA, perimeter and long axis of the median nerve were significantly different between normal and abnormal NCS wrists. Mixed model analysis showed that subclinical neuropathy was associated with enlarged CSA, but the other demographic variables (gender, age and body mass index and occupational categories) were not. Our findings support the use of both patient symptoms and NCS to define normal subjects during further studies. In addition, enlarged CSA within asymptomatic individuals should raise concern for subclinical median neuropathy.

Scaphocapitate Arthrodesis for Treatment of Scapholunate Instability in Manual Workers

To assess the long-term efficacy of scaphocapitate arthrodesis for treatment of chronic scapholunate instability in high-demand patients. We retrospectively analyzed the clinical and radiographic results of 20 manual workers who underwent scaphocapitate arthrodesis for chronic scapholunate instability at a mean follow-up of 10 years (range, 1-23 y). We measured range of motion and grip strength; pain on a scale of 0 to 5; Quick Disabilities of the Arm, Shoulder, and Hand score; and ability to return to work. We assessed radiographs for union, carpal height and alignment, signs of ulnar translation or radiocarpal arthritis, and hardware problems. At most recent follow-up, the arc of motion averaged 87° for flexion-extension and 41° for the radioulnar deviation. The postoperative average maximum grip strength was 21 kg, which was 60% of the opposite, normal wrist. Pain was significantly reduced. The average postoperative Quick Disabilities of the Arm, Shoulder, and Hand score was 19, and the return-to-work rate was 90%. Radiographic analysis showed union in all patients, improvement of carpal height and scaphoid angle, no evidence of ulnar translation, and a 30% rate of radiocarpal osteoarthritis. This report of long-term results demonstrates the efficacy of scaphocapitate limited carpal arthrodesis for the treatment of chronic rotatory subluxation of the scaphoid. We conclude that continued use of this procedure is warranted. Therapeutic IV.

Wrist Biomechanics: In the Normal Wrist, Following Injury and After Surgical Treatment

Biomechanical studies have shown that surgical treatments for osteoarthritis and rheumatoid arthritis frequently decrease the amount of possible wrist motion, alter the load distribution between the radius and ulna and increase the contact pressure in the wrist joint. Both wrist motion and carpal bone motion are decreased with carpal bone arthrodesis and wrist ligament injury. Relative loading between the distal radius and ulna is altered by ulnar shortening. Carpal bone fusion alters the wrist joint contact pressure. Research continues to be needed to biomechanically examine the consequences of surgical treatments as well as to evaluate the long term clinical consequences of surgery. Keywords: Wrist biomechanics, kinematics , kinetics

MID-MOTION DEFORMATION OF MEDIAN NERVE DURING FINGER FLEXION: A NEW INSIGHT INTO THE DYNAMIC AETIOLOGY OF CARPAL TUNNEL SYNDROME

Carpal tunnel syndrome (CTS) exists in a spectrum of severity and symptoms with a dynamic component. We aim to study dynamic nerve-tendon interrelationships in normal and mild CTS wrists during a fist motion, with dynamic ultrasound. We observed that in normal wrists, the nerve arcs in an ulnar-volar direction and changes from a circular shape to a flat oval during motion. In CTS candidates, however, the curvature and distance of the nerve's path are reduced, while nerve shape remains relatively constant. In all candidates, the nerve is compressed against the flexor retinaculum, with the nerve subject to less compression in normal candidates as it moves dorsally into a recess. These findings suggest that besides mechanical compression from increased carpal tunnel contents alone, a decrease in nerve gliding movement may lead to CTS symptomatology. Furthermore, we identified that maximum nerve deformation occurs mid-motion, supporting the use of wrist splints for symptom relief.

ACCURATE QUANTITATIVE MEASUREMENT OF LUNATE UNCOVERING RATIO — IS GILULA'S SEMIQUANTITATIVE TEST RELIABLE?

The Gilula's test suggests the presence of ulnocarpal translation when 50% or more of the lunate lies medial to the ulnar edge of radius. The purpose of this study was to examine the reliability of this semiquantitative test as there was inconsistency between the previous publications in regarding 50% as the cutoff value for the normal lunate uncovering ratio (LUR). We utilized the Picture Archiving and Communication System to investigate radiographs of 299 normal adult wrists and emphasized defined radiographic landmarks for accurate quantitative measurement. Our mean LUR was 35%(SD8) with a range of 8 to 49%. Therefore we re-affirmed the reliability of the Gilula's test since none of our normal wrists had a LUR of 50% or greater.

SCAPHOID TRANSLATION MEASUREMENTS IN NORMAL WRISTS

The purpose of this study was to establish a normal measure of scaphoid position in the radioulnar plane in standard neutral, radial and ulnar deviation posteroanterior radiographs. This measurement may allow indirect evaluation of the radiocarpal ligaments and comparison between normal and pathologic states (following radius fractures, perilunate dislocations). Measurements were trialed on 74 normal wrist radiographs and 25 cadaver wrists. We evaluated the distance between the radial styloid and the scaphoid and corresponding scaphoid width. The ratio of distance/width at the mid styloid level (0.35, imprecision SD = 0.1) had the lowest random error and is therefore the most precise measurement of true scaphoid translation. This measurement is independent of scapholunate ligament integrity and may provide a better assessment of the radiocarpal component of ulnar translational instability. Abnormal movement of the scaphoid in the radioscaphoid joint likely reflects ligamentous injury. Identifying and addressing these injuries may prevent the development of arthritis.

In-vivo dynamic and static three-dimensional joint space distance maps for assessment of cartilage thickness in the radiocarpal joint

BackgroundThe assessment of the joint space thickness is an important clinical parameter for diagnosing osteoarthritis. The accuracy of joint space thickness evaluation from radiographs is limited due to anatomical complexity of the wrist. We propose using distance maps estimated from 3-dimensional and 4-dimensional images reflecting joint space thickness distribution over the relevant part of the articular surface. MethodsIn this paper we investigate the difference between joint space thicknesses acquired from dynamic distance maps to static distance maps. A dynamic distance map gives for every point on a subchondral bone surface the shortest distance to the opposing subchondral bone surface during wrist motion. We hypothesize that the joint space thickness calculated from dynamic distance maps provide a better reflection of the functional joint space thickness. The diagnostic potential of the dynamic joint space thickness measurement is illustrated by comparing data from distance maps of osteoarthritic wrists with normal wrists. FindingsIn 10 healthy wrists which are examined, dynamic joint space thickness is smaller than static acquired joint space thickness suggesting that dynamic distance maps provide a better estimate of the measured joint space thickness than joint space thickness based on a static joint space thickness. In 3 examined osteoarthritic wrists the joint space thickness is smaller than in healthy individuals. Moreover, the difference between dynamic and static joint space thickness is smaller in pathological joint parts. InterpretationThe method presented in this paper demonstrates the feasibility of in vivo dynamic distance maps to detect joint space thickness in the radiocarpal joint of healthy individuals.

Assessment of Velocity, Range, and Smoothness of Wrist Circumduction Using Flexible Electrogoniometry

To quantify the range, velocity, and smoothness of wrist circumduction, to explore the oblique functional plane of wrist circumduction, and to establish the reproducibility and reliability of these measures. Forty healthy subjects with a mean age of 43 years and without a history of wrist pathology or pain participated in this study. We used a flexible electrogoniometer with a twin-axis sensor to measure the relative angles between the 2 end blocks while the subject performed maximum excursion of flexion-extension, radioulnar deviation, and circumduction of the wrist held in a standardized, fully pronated position. A software package was used to further analyze the characteristics of the circumduction curve or oval such as the mean area (designated as degree-degree or oo) shape, size, rate, smoothness, and orientation. The mean area of circumduction (4729 [degree-degree]) and circumference (265°) of the circumduction curve indicated the total range of circumduction. The velocity of circumduction (mean 179°/s) and the time (1.6 second) taken to complete 1 cycle of circumduction were similar in both hands. The 4 quadrants for the velocity of circumduction showed that the velocity was faster in the radioulnar deviation quadrants compared with flexion and extension. Quadrant analysis showed the smoothness was greater in the radioulnar deviation quadrants than in the flexion and extension quadrants. The oblique planes of the circumduction curves of all the normal wrists lie in ulnopalmar and radiodorsal direction with a mean angle of 28° to the vertical flexion and extension plane. This technique was accurate and reliable in measuring the velocity, range, and smoothness of wrist circumduction.

Scaphoid Fracture: Functional Outcome Following Fixation with Herbert Screw

Most scaphoid fractures though heal uneventfully with cast treatment, immobilization with cast is associated with complication like wrist stiffness. Open reduction and fixation with Herbert Screw though technically demanding procedure can yield excellent results and prevents complication like nonunions and loss of wrist function. To assess clinical outcome and radiological union of scaphoid fracture after operative management following Herbert screw fixation in patient attending Dhulikhel Hospital. All scaphoid fracture, treated from Feb 2007 till Feb 2011, were retrospectively studied in Dhulikhel Hospital, Kathmandu University Hospital. Fifteen patients with scaphoid fractures were treated with Herbert screw. Fourteen were males and one was female. Serial radiographs were taken to assess radiographic union and functional outcome was assessed using Modified Mayo wrist score. Out of 15 patients, 13 scaphoid had waist fractures and two had proximal pole fractures. All scaphoid were treated with open reduction and Herbert screw fixation either by volar approach or by dorsal approach. All fractures maintained good alignment post operatively. Nine (60%) patients had excellent results with normal wrist range of motion, five (33.3%) patients had good results and one (6.7%) patient had poor outcome. In 14 (93.3%) patients good radiological union was seen at final follow up at six months time. Fixation with Herbert screw for scaphoid fracture is an effective and convenient way of treatment with satisfactory functional outcome and less complication.

Bicolumnar Fusion for Scaphoid Nonunion Advanced Collapse Without Bone Grafting

Scaphoid nonunion advanced collapse leading to wrist osteoarthritis is treated by 4-corner fusion, capitolunate arthrodesis, and 3-corner fusion with a variety of hardware and bone grafting techniques as reported in the literature. However, such procedures have been associated with complications such as nonunion, hardware failure, and deep infection. On the basis of the same concept of these intercarpal fusions with the aim to transmit the load of the wrist, we present bicolumnar fusion to fuse the capitolunate articulation and the triquetrohamate articulation and preserve the articulation between the 2 columns, maintaining much of the normal anatomy and physiology of the normal wrist. This technique has allowed the use of screws for compression of both articulations and achieve union without the use of bone grafting.

3차원 영상을 이용한 다트 던지기 운동에서의 주상골, 유두골, 월상골의 움직임 분석

The primary purpose of this study was to analyze the motion of the scaphoid, capitate, and lunate during dart-throwing motion by three-dimensional modeling. Five series of CT images of five normal right wrists were acquired from five motion steps from radial extension to ulnar flexion in the dart-throwing motion plane. Segmentation and three-dimensional modeling of bones from CT images was performed using Analyze. Distances among centroids of the scaphoid, capitate and lunate and angles between principal axes of three carpal bones were calculated to analyze the motion by using MATLAB. As the wrist motion changed from radial extension to ulnar flexion, the distance between two adjacent bones decreased. The scaphoid and lunate rotated less than the capitates during dart-throwing motion. This study reports the Three-dimensional in vivo measurement of carpal motion using CT images.