Dart-throwing Motion Research Articles

Analysis of a New Artificial Muscle Type Dynamic Orthosis for Wrist Joint Disease Using a Three-dimensional Motion Analyzer.

ABSTRACTObjectives:Recently, the dart-throwing motion (DTM) has attracted attention as a functional direction of wrist joint motion. Consequently, we devised a new artificial muscle-type dynamic orthosis (Dynamic Traction Splint by Artificial Muscle, DTSaM) to reproduce DTM. This study analyzed the automatic motion of the wrist joint using a three-dimensional motion analysis system to assess how closely the DTSaM replicates DTM.Methods:The DTSaM orthosis incorporates two McKibben-type rubber artificial muscles, and measurements were performed using image analysis software and a three-dimensional motion analysis system. The wrist radial angle (WRA) was defined as the angle between the line connecting the head of the index finger metacarpal to the radial styloid process and the line connecting the radial styloid process to the lateral epicondyle of the humerus. WRAs were investigated from 60° of palmar flexion to 60° of dorsiflexion.Results:For dorsiflexion, comparisons of radial deviation and wrist ulnar angle (WUA) between the motion obtained using the DTSaM orthosis and active DTM showed a significant difference (P <0.05) at 30° and 60°, respectively. For palmar flexion, the same comparison showed a significant difference for both the ulnar and radial deviations (30°, P <0.05; and 60°, P <0.01, respectively). Furthermore, WUA showed a significant difference at 50° (P <0.05). Intraclass correlation coefficient analyses yielded good reliability with an average value of ≥0.8.Conclusion:The DTSaM orthosis produces a motion similar to the DTM. It is hoped that the use of the DTSaM orthosis will help to shorten the treatment period for patients with wrist disease.

A Biomechanical Evaluation of the ECRL Tenodesis for Reconstruction of the Scapholunate Ligament

Reconstruction of the scapholunate ligament (SLL) in the setting of dynamic instability remains a surgical challenge, with lack of consensus on the best reconstructive procedure. Reconstruction of only the dorsal component may lead to volar gapping and abnormal wrist kinematics. This cadaveric active motion simulation study determined whether scapholunate (SL) motion, angulation, and contact are restored following open reconstruction using the extensor carpi radialis longus (ECRL) tenodesis, which reconstructs both the volar and the dorsal SLL components. Seven fresh-frozen cadaveric upper limbs (mean age, 68 ± 10.1 years) underwent a 4-stage protocol of cyclic dart-throw motion and flexion-extension motion (utilizing an active wrist motion simulator that used tendon load/motion-controlled actuation. Scaphoid and lunate motion, relative scaphoid translation, SL angle, and dorsal-volar SL diastasis were measured with (1) wrist ligaments intact, (2) following complete sectioning of the SLL, and (3) following SL reconstruction using the ECRL tenodesis technique. Complete SLL sectioning resulted in a typical pattern of SL instability. Following the ECRL tenodesis, lunate extension was not corrected. Scaphoid flexion, however, was not significantly different from the native state in FEM but remained significantly flexed during dart-throw motion. Differential dorsal and volar gapping did not significantly improve following ECRL tenodesis (dorsal, 1.2-2.3 mm; volar, 1.1-1.7 mm). This biomechanical study demonstrates that the ECRL tenodesis did not fully restore native carpal kinematics, despite dorsal and volar SLL, and scaphotrapeziotrapezoid reconstruction. Therapeutic IV.

Biomechanical Effects of Radioscapholunate Fusion With Distal Scaphoidectomy and Triquetrum Excision on Dart-Throwing and Wrist Circumduction Motions

Distal scaphoid and triquetrum excisions can improve the range of wrist motion after radioscapholunate (RSL) fusion, but little is known about the kinematics of dart-throwing and global circumduction motions. We hypothesized that these excisions could increase the range of motion without causing midcarpal instability. Seven fresh-frozen cadaver upper extremities were mounted on a testing apparatus after isolation and preloading of the tendons of the flexor carpi radialis, flexor carpi ulnaris, extensor carpi radialis, and extensor carpi ulnaris. Sequential loadings of the flexor carpi ulnaris and extensor carpi radialis simulated active dart-throwing motion. Passive circumferential loading produced the wrist circumduction motion. We measured the range of wrist motions with an electromagnetic tracking system in 4 experiments: intact, simulated RSL fusion, RSL fusion with distal scaphoid excision, and RSL fusion with distal scaphoid and total triquetrum excisions. To evaluate midcarpal stability, we conducted passive mobility testing of the distal carpal row in the radial, volar, ulnar, and dorsal directions. Radioscapholunate fusion decreased the dart-throwing motion to a mean of 46% of the baseline value; distal scaphoid and triquetrum excisions increased the mean arc to 50% and 62%, respectively. Radioscapholunate fusion diminished the wrist circumduction to a mean of 43% of the baseline value, which increased to a mean of 58% and 74% after distal scaphoid and triquetrum excision, respectively. A significant increase in radial deviation was noted after distal scaphoid excision, and subsequent triquetrum excision significantly increased motion in the ulnar-palmar direction. Regarding midcarpal stability, dorsal translation significantly increased after distal scaphoid and triquetrum excisions. Distal scaphoid and triquetrum excision after RSL fusion improved both dart-throwing and circumduction motions, but dorsal midcarpal instability occurred. Subsequent carpal excisions may improve short-term outcome by increasing motions in a RSL-fused wrist; however, a potential risk of midcarpal instability should be considered.

How Much Scaphoid Can be Safely Resected? A Biomechanical Analysis of the Effects of Distal Scaphoid Resection.

Resection of the distal pole of the scaphoid has been advocated as a simple alternative to other wrist salvage procedures for scaphoid nonunion advanced collapse and scaphotrapezio-trapezoid arthritis. However, the extent of scaphoid that may be resected without adversely affecting carpal kinematics has never been clearly defined. Seven cadaveric upper extremities were tested in a custom motion wrist simulator. A 3-stage sequential sectioning of the distal scaphoid protocol was performed in 25% increments then cyclic active wrist flexion-extension and dart thrower's motion trials were recorded. The extent of distal scaphoid resection had no effect on overall wrist range of motion. The lunate assumed a more extended position following resection of the distal scaphoid compared to intact. At 25%, 50%, and 75% of distal scaphoid resection, the lunate extended to 13.32° ± 9.4°, 23.43° ± 7.5°, and 15.81° ± 16.9°, respectively. The capitate migrated proximally with 25% and 50% distal scaphoidectomy, and proximally and radially with 75% of the scaphoid resected. Resection of 75% of the scaphoid resulted in unstable wrist kinematics. Resection of up to 25% of the distal scaphoid did not significantly influence carpal kinematics and induced mild lunate extension deformity. Resection of 50% of the scaphoid induced further and potentially clinically significant lunate extension and dorsal intercalated segment instability. Further removal of 75% of the distal scaphoid induced capitate migration radially and unpredictable wrist kinematics. Consequently, removal of over 25% of the scaphoid should be avoided or supplemented with partial wrist fusion.

Loading at the distal radius and ulna during active simulated dart throw motion

Loading at the distal forearm during dart throw motion (DTM) has been examined under static loads but there is no consensus on how loading is affected by active motion. In this work two implants were designed to measure forearm loading in a cadaveric model of wrist motion. Loads through the radius and ulna were significantly greater in reverse DTM than forward DTM. Radius loads were greatest in extended and radial deviated positions, and ulnar loads were greatest in flexed and ulnar deviated position. This work gives insight into the biomechanics of loading of the forearm to guide further studies.

Home exercise in the dart-throwing motion plane after distal radius fractures: A pilot randomized controlled trial

IntroductionDuring daily functions, our wrist moves through an oblique plane, named the dart-throwing motion (DTM) plane. This plane is considered a more stable plane because the proximal carpal row remains relatively immobile. However, rehabilitation programs that incorporate exercising in the DTM plane have yet to be explored. Purpose of the StudyThe purpose of this study was to evaluate the rehabilitation outcomes after treatment in the DTM plane compared with outcomes after treatment in the sagittal plane after distal radius fracture. Study DesignThis is a pilot randomized controlled trial. MethodsSubjects after open reduction internal fixation were assigned into a research group (N = 12; ages 48.7 ± 7.3) and a control group (N = 12; ages 50.8 ± 15). The control group activated the wrist in the sagittal plane, whereas the research group activated the wrist in the DTM plane. Range of motion, pain levels, functional hand motor skills tests, and satisfaction from self-training exercise were measured before and after a 12-session intervention. ResultsThe outcome measures were similar between the treatment groups. The research group reported significantly higher satisfaction rates than the control group on topics such as general satisfaction (research group: 3.4 ± 0.7, control group: 2. 5 ± 1.2, P = .030), motivation to exert oneself (research group: 2.8 ± 1.0, control group: 2.3 ± 1.2, P = .009), progressed function (research group: 3.4 ± 0.7, control group: 2.4 ± 1.1, P = .012), and self-training contribution to the daily function (research group: 3.4 ± 0.7, control group: 2.5 ± 1.2, P = .030). Discussion and ConclusionPilot results do not favor one treatment method over the other. However, exercising in the DTM plane may contribute to the satisfaction of the client and increase self-training motivation.

Functional Dart-Throwing Motion: A Clinical Comparison of Four-Corner Fusion to Radioscapholunate Fusion Using Inertial Motion Capture.

Background Dart-throwing motion (DTM) is an important functional arc of the wrist from radial extension to ulna flexion. An aim of partial fusion surgery of the wrist is to maintain maximal functional motion while addressing the pathology. The radioscapholunate (RSL) fusion, accompanied with partial resection of the distal scaphoid, is thought to allow better DTM than other partial wrist fusions such as the four-corner fusion (4CF). Question Does an RSL fusion allow better functional DTM than 4CF, and how does this range compare with healthy wrists and the patient's contralateral wrist? Patients and Methods Patients who have undergone an RSL fusion or 4CF at our tertiary center were identified and invited to present to have their DTM arc measured. To accurately measure DTM, a previously validated inertial measurement device was used. Patient's functional DTM arc was measured in both unrestrained (elbow and shoulder free to move) and restrained (elbow and shoulder immobilized) fashions. This was compared with their contralateral wrist and a group of healthy control volunteers. Results Overall five RSL fusions, 10 4CF and 24 control patients were enrolled in the study. There was no significant difference between functional DTM when 4CF and RSL fusion were compared. Both had significantly reduced functional DTM arc than control patients. There was no significant difference between the operated wrist compared with the patient's contralateral unoperated wrist. Conclusion RSL fusion is not significantly better at maintaining functional DTM when compared with 4CF. Both surgeries result in decreased functional DTM arc when compared with control patients. This is a cohort study and reflects a level of evidence IV. Level of Evidence This is a Leve IV, cohort study.

Proposal for a Method to Measure the Range of Dart-Throwing Motion

PurposeTo examine the reliability of a novel technique to measure the range of the dart-throwing motion.MethodsTwo raters measured the range of the dart-throwing motion in 40 healthy subjects. For the measurement, subjects were asked to perform a simulated hammering motion using various experimental tools (a real hammer, a thick wooden rod, and a thin wooden rod). The inclination angle of the tool in the vertical plane was measured with a manual goniometer at the maximal position of radial extension and ulnar flexion. The sum of these angles was defined as the range of the dart-throwing motion. To evaluate relative interrater reliability, intraclass correlation coefficients were calculated. To account for absolute reliability, Bland-Altman analysis was performed.ResultsIntraclass correlation coefficients ranged 0.72 to 0.86. Bland-Altman analysis revealed that some systematic errors existed when the measurement was carried out with the real hammer or the thin rod, but not the thick rod. The 95% confidence intervals of minimal detectable change for the thick rod were 36.0° and 35.8° for the dominant and nondominant sides, respectively. Measured values between the experimental tools were similar.ConclusionsRelative reliability was shown to be good or moderate for each set of measurements. Some refinements are required to reduce measurement error. Accuracy of measurement should also be confirmed.Clinical relevanceNo standardized methods for measuring the range of the dart-throwing motion have yet been established. Our technique can be performed rapidly and with easily available materials, producing reliable measurements for the range of the dart-throwing motion.

Dorsal Intercarpal Ligament Preserving Arthrotomy and Capsulodesis for Scapholunate Dissociation

Carpal instability secondary to scapholunate (SL) ligament tears can lead to a significant disability of the wrist. Different surgical procedures have been proposed to treat SL instability. A variety of dorsal capsulodesis techniques tethering the scaphoid have been used in patients with SL dissociation. We report a novel technique of modified dorsal intercarpal ligament (DICL) capsulodesis for the treatment of SL dissociation. The surgical indication for this procedure is complete SL ligament tear with a reducible carpal malalignment and no secondary osteoarthritis. This procedure is indicated when the remnant of torn ligament in the dorsal SL interosseous space is available for repair. First, carpal malalignment is corrected and the scaphoid and the lunate are temporarily fixed with a transosseous screw or Kirschner wires. Using a dorsal approach, the DICL is then exposed, which originates from the triquetrum and attaches to the scaphoid, trapezium, and trapezoid. The distal and proximal borders of the ligament are identified and elevated without detaching the attachment sites. The DICL is transferred proximally to reinforce the dorsal SL interosseous ligament. The wrist joint is immobilized for 3 weeks postoperatively, and dart-throwing motion is permitted until temporary SL fixation is removed at 2 to 3 months after surgery. A wrist brace is recommended until 3 to 6 months after the first surgery depending on the patient's occupation and sports activity.

The effect of surgery for basal osteoarthritis of the thumb on dart thrower's motion.

This study aimed to identify the effects of basal thumb surgery on the range of dart thrower's motion. Thirteen fresh-frozen cadaveric specimens were placed in a customized jig. Simulated scaphotrapeziotrapezoid joint fusion was carried out on all specimens. Half the specimens then underwent trapeziectomy and the rest had excision of the distal pole of the scaphoid. Simulated scaphotrapeziotrapezoid fusion reduced the range of dart thrower's motion to 89% of the range in the intact wrists, from a mean of 117° to 104°. Although this reduction is not large, it was statistically significant. Simulated trapeziectomy caused a very small increase in dart thrower's motion range compared with the range in the intact wrists. Simulated distal pole of scaphoid excision did not change the range of dart thrower's motion. These results may inform preoperative decisions for surgical management of basal osteoarthritis of the thumb.

In-vivo three-dimensional motion analysis of the wrist during dart-throwing motion after midcarpal fusion and radioscapholunate fusion.

We recorded the dart-throwing motion and basic motion tasks in patients following radioscapholunate fusion and midcarpal fusion with a three-dimensional motion capture system invivo, using digital infrared cameras to track the movement of reflective skin markers on the hand and forearm. During the dart-throwing motion, 20 healthy volunteers showed a median range of motion of 107°. As expected, patients had significantly reduced wrist range of motion during basic motion tasks and dart-throwing motion compared with the healthy controls, except for ulnar flexion occurring in the dart-throwing motion in patients treated by midcarpal fusion and radial deviation after midcarpal fusion or radioscapholunate fusion. In addition, patients who had undergone radioscapholunate fusion had significantly reduced range of motion during dart-throwing motion compared with patients after midcarpal fusion.

CT を用いた手関節リバース・ダーツスロー・モーションの3 次元動態解析:─橈骨手根関節と手根中央関節の回転角度と運動方向の検討─

CT を用いた手関節リバース・ダーツスロー・モーションの3 次元動態解析:─橈骨手根関節と手根中央関節の回転角度と運動方向の検討─

Exo-Wrist: A Soft Tendon-Driven Wrist-Wearable Robot With Active Anchor for Dart-Throwing Motion in Hemiplegic Patients

Constraint-induced movement therapy (CIMT) is an effective recovery protocol for patients with stroke. However, not all the stroke patients can participate in CIMT. Devices that assist the movement of the affected side could help increase the number of stroke patients who can participate in CIMT like protocol. In this letter, a soft cable-driven wrist-wearable robot called Exo-Wrist, which assists the wrist of a paretic arm in performing the dart-throwing motion (DTM) with an active forearm anchor, is proposed. To increase the force transmission efficiency while preventing medical issues due to long-term pressure, a corset active anchor, which compresses the body only when anchoring is needed, is developed. A moving pulley mechanism and a three-layered structure increase the functionality of the anchor. Considering the natural movement of wrist extension and the frequently-used wrist motions in daily life, the wrist is assisted along the DTM direction, and the method to find a personal DTM is introduced. A 3D-printed custom wrist armlet is developed to hold the tendon path and exert a torque along the DTM direction. Together with a hand assistive device, Exo-Wrist could be used as a tool to help stroke patients with difficulty in wrist extension to participate in task-oriented rehabilitation protocols such as CIMT.

Functional Dart Thrower’s Motion (DTM) of the Wrist and the Injured Scapholunate Interosseous Ligament: A Scoping Review

Abstract Date Presented 04/05/19 Primary Author and Speaker: Jamie Bergner Contributing Authors: Jennifer Farrar, Rogelio Coronado

Does Object Height Affect the Dart Throwing Motion Angle during Seated Activities of Daily Living?

Complex wrist motions are needed to complete various daily activities. Analyzing the multidimensional motion of the wrist is crucial for understanding our functional movement. Several studies have shown that numerous activities of daily livings (ADLs) are performed using an oblique plane of wrist motion from radial-extension to ulnar-flexion, named the Dart Throwing Motion (DTM) plane. To the best of our knowledge, the DTM plane angle performed during ADLs has not been compared between different heights (e.g. table, shoulder and head height), as is common when performing day-to-day tasks. In this study, we compared DTM plane angles when performing different ADLs at three different heights and examined the relationship between DTM plane angles and limb position. We found that height had a significant effect on the DTM plane angles - the mean DTM plane angle was greater at the lower level compared to the mid and higher levels. A significant effect of shoulder orientation on mean DTM plane angles was shown in the sagittal and coronal planes. Our findings support the importance of training daily tasks at different heights during rehabilitation following wrist injuries, in order to explore a large range of DTM angles, to accommodate needs of common ADLs.

Implementation of the Dart-throwing Motion Plane in Hand Therapy After Distal Radius Fractures

Implementation of the Dart-throwing Motion Plane in Hand Therapy After Distal Radius Fractures

Dart thrower's motion and the injured scapholunate interosseous ligament: A scoping review of studies examining motion, orthoses, and rehabilitation

Study DesignScoping review. IntroductionDart thrower's motion (DTM) of the wrist primarily arises from the midcarpal joint, and minimizes stress to the scapholunate interosseous ligament (SLIL). After SLIL injury or surgery, early controlled DTM may reduce the effects of prolonged immobilization, while protecting SLIL integrity. Purpose of the StudyTo summarize the literature on the effects of DTM on the injured and surgically repaired SLIL and the extent to which various DTM orthotic designs promote SLIL recovery. MethodsA systematic literature search was conducted within 6 databases for articles published between 2003 and March 2018. Eligible studies examined DTM in the context of SLIL injury or repair. Relevant data were extracted by 2 independent reviewers. ResultsOf 425 identified articles, 15 were eligible for inclusion. Five biomechanical studies examined the influence of DTM on the injured SLIL, whereas 5 articles described DTM orthotic designs. Also included were five articles that reported outcomes when DTM was used in the rehabilitation protocol. DiscussionThe included studies suggest limiting end ranges of DTM in the injured/repaired SLIL, while blocking orthogonal plane movements. Custom orthotic designs may accomplish this goal. DTM has been used in comprehensive therapy programs in small case studies reporting short-term and intermediate clinical outcomes. ConclusionsCaution should be exercised with using DTM on the torn SLIL as gap increases, particularly at the end-range motion. Orthosis designs have potential to limit this motion to midrange, while allowing early movement. Further high-level research is needed to understand the influence of DTM on injured and postsurgical populations.

Test-retest reliability of goniometric measurements of the range of dart-throwing motion.

[Purpose] To examine the reliability of using a manual goniometer for measuring the range of dart-throwing motion. [Participants and Methods] The range of dart-throwing motion in 24 healthy participants was measured by three raters on the same day, and one rater repeated the measurement on another day of the same week. The stationary arm of the goniometer was placed along the radius, and the moveable arm was placed along the shaft of the second metacarpal, approximately 45° supinated from Lister’s tubercle. All of the participants performed the dart-throwing motion on a plane that passed through the anatomical neutral wrist position, inclined 45° to the orthogonal anatomical plane. [Results] The intra-rater reliability was moderate (0.5–0.75) only for some parameters of the radial extension, and the intraclass correlation coefficients (ICCs) of all other parameters were <0.5. For the inter-rater reliability, the ICCs of all parameters were <0.5. Brand-Altman analysis revealed some fixed biases between the raters, although no proportional bias was observed. [Conclusion] The goniometric measurement procedure examined in this study appeared to be unsuitable for clinical use because of its poor reliability.

Wrist Plane of Motion and Range During Daily Activities

The dart-throwing motion (DTM) is a multiplane wrist motion that is needed for many daily occupations. Mobilization along the DTM plane may be essential for rehabilitation after wrist injury, but DTM angles are reported for the dominant hand alone, so their relevance to injury in the nondominant hand cannot be surmised. The aim of this study was to quantify the DTM plane angles for both hands during different activities of daily living (ADLs). Forty-three healthy participants wore a twin-axis electrogoniometer during ADLs. No significant differences were found between the DTM plane angles of the dominant (20°-45°) and nondominant (15°-40°) hands. These angles varied by task and across participants. The DTM plane is a functional motion used by both hands during ADLs. Because the DTM plane angle differs among hands, tasks, and individual clients, wrist rehabilitation involving the DTM plane should not be limited to a singular DTM plane angle.

Qualification of Wrist Functional Performance During Dart Thrower's Movement.

Recently, numerous comprehensive studies have been concentrating on the intricate kinematics of the wrist joint functionality captured with dart thrower's movement. It is envisaged that the wrist capability in performing daily activities can be more accurately characterized or encapsulated in the dart thrower's movement. This study examines the characteristic function of wrist movements during dart-throwing motion using only gyroscopic data measured from inertial sensors. A multi-dimensional form of dart throwing trajectory is described using quaternion representation associated with distance metric to quantitatively validate the functional wrist performance between two cohorts; healthy controls and patients. Eight normal subjects and eight patients engaged in a series of clinical trials conducted after undergoing post-surgical reconstructive procedures of the wrist joint. The discriminative results in terms of silhouette clustering evaluation show that the use of distance metric values based quaternion trajectory is well-matched consistently with subjective expert assessments. Our proposed approach captures the relative motions underpinning the wrist joint instead of relying on the traditional measure based on the range of motion measure. Therefore, this paper proposes a reliable approach to dynamically capture the wrist functionality during dart thrower's movement; a movement envisaged to describe the ability to engage in daily life activities. These quantitative outcomes in terms of measurement consistency will provide insightful information in understanding the significant changes in wrist joint signatures associated with various scenarios.