Clinical measurement of functional dart thrower's motion in patients with unilateral wrist conditions undergoing nonoperative or postoperative hand therapy

STUDY DESIGN

Cross-sectional and descriptive study BACKGROUND: Functional dart thrower's motion (F-DTM) is an obliquely oriented wrist motion that occurs in activities such as throwing and drinking from a cup. There is limited data on clinical measurement of F-DTM.

PURPOSE OF THE STUDY

The purpose of this study was to 1) describe and establish reference scores for F-DTM measurement for nonoperative and postoperative wrist patients 2) compare F-DTM between the affected and nonaffected sides and 3) determine F-DTM score agreement across three consecutive trials.

METHODS

Two certified hand therapists evaluated F-DTM in consecutive adult patients with a unilateral wrist condition undergoing nonoperative or postoperative therapy. Three trials of goniometer measurements for radial extension (RE) and ulnar flexion (UF) were assessed on the nonaffected and affected wrists. A total arc F-DTM was computed. Mean, 95% confidence intervals (CI), and Cohen's d effect size described side-to-side differences in RE, UF, and total arc F-DTM. Agreement in scores across trials was assessed with an intraclass correlation coefficient (ICC).

RESULTS

Thirty-one nonoperative (mean ± SD age = 40.0 ± 13.9 years, 74% female, 94% right hand dominant) and 44 postoperative patients (mean ± SD age = 44.9 ± 14.9 years, 66% female, 84% right hand dominant) were enrolled. The average side-to-side difference, in degrees, in the nonoperative group was -6.4 (95% CI: -9.4 to -3.4, Cohen's d = 0.8) for RE, -10.4 (-16.7 to -4.0, d = 0.6) for UF, and -16.8 (-24.3 to -9.2, d = 0.8) for total arc F-DTM. The average side-to-side difference in the postoperative group was -33.6 (-38.8 to -28.3, d = 1.9) for RE, -34.7 (-40.6 to -28.7, d = 1.8) for UF, and -68.2 (-77.9 to -58.5, d = 2.1) for total arc F-DTM. The range of ICCs for F-DTM measurements was 0.82-0.96.

CONCLUSIONS

Goniometer measurement of F-DTM is a clinically feasible method to quantify functional motion loss in an injured wrist population, particularly patients with postoperatively managed wrist conditions.

Creation of 3D anatomical models illustrating an intact and centrally torn triangular fibrocartilage complex for patient education prior treatment

BACKGROUND

The triangular fibrocartilage complex (TFCC) is a composite structure located in the human wrist and is made up from fibrocartilage and ligaments. It consists of eight distinct structures, with the ligamentous structures acting as the major stabilizer of the distal radioulnar joint and with the articular disc acting as a shock absorber at the ulnocarpal joint. The articular disc can be called the triangular fibrocartilage (TFC). Thus, traumatic injuries of the TFCC ligamentous structures cause instability of the joint and a centrally torn TFC disc causes ulnar sided wrist pain. TFCC pathologies can be difficult for patients to understand in clinic, due to their complex three-dimensional (3D) nature. The purpose of this study was to produce 3D anatomical models illustrating the normal anatomy of the wrist joint with the TFCC structure and a pathological model with a centrally torn TFC. These models would be used in a hand clinic to aid explanation of this complex three-dimensional anatomical structure and their injury to patients and trainee doctors.

MATERIALS

Three fresh frozen forearm and hand specimens were dissected, 3D scanned, 3D printed and painted. These models were introduced into a hand clinic to aid explanation of the complex anatomical structures, with the first 50 patients being asked, on a visual analog scale of 0-10, to state how much the models helped their understanding of the condition.

RESULTS

Three 3D printed anatomical models were produced to illustrate the (1) forearm muscles and wrist tendons, (2) an intact TFC and (3) a centrally torn TFC. 48 of 50 patients surveyed completed the scale, with an average rating of 8.7 increase in understanding with the models.

CONCLUSION

Patient education and understanding is crucial as it enhances decision making between surgeon and patient. These 3D anatomical models were shown to increase patient's understanding of the pathology. This should consequentially improve discussions on corresponding treatment options during consultation.

A Reference Range of Dart-Thrower's Motion at the Wrist in a Healthy Adult Population

PURPOSE

Dart-thrower's motion (DTM) is a functional wrist movement from maximum radial extension to maximum ulnar flexion. This study defines a reference range of DTM in a healthy population.

METHODS

Goniometric measurements were collected from both wrists of 200 healthy volunteers. Mean age was 21.1 years (range, 18-25 years), 126 volunteers (63%) were female, and 177 (89%) were right-handed. Volunteers also reported perceived difficulty of performing DTM.

RESULTS

For male subjects, the mean arc of motion was 126° (range, 83°-166°) for dominant and 114° (range, 62°-148°) for nondominant wrists. For female subjects, the mean values were 129° (range, 79°-170°) and 126° (range, 70°-167°), respectively. On multiple regression analysis, female subjects had a significantly increased range of dominant and nondominant arc of motion compared with males. Older subjects had significantly increased dominant but reduced nondominant arc of motion. High inter- and intrarater reliability was observed for goniometric measurement of DTM (intraclass correlation coefficients, 0.93-0.98).

CONCLUSIONS

This study quantified a reference range of DTM in normal individuals.

CLINICAL RELEVANCE

This study provides a reference range for DTM in a young adult population, which may aid clinical comparison of measurements of wrist movement and evaluation of conditions and treatments that impact DTM.

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

STUDY DESIGN

Scoping review.

INTRODUCTION

Dart 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 STUDY

To 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.

METHODS

A 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.

RESULTS

Of 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.

DISCUSSION

The 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.

CONCLUSIONS

Caution 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.

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.

Clinical measurement of the dart throwing motion of the wrist: variability, accuracy and correction

Despite being functionally important, the dart throwing motion is difficult to assess accurately through goniometry. The objectives of this study were to describe a method for reliably quantifying the dart throwing motion using goniometric measurements within a healthy population. Wrist kinematics of 24 healthy participants were assessed using goniometry and optical motion tracking. Three wrist angles were measured at the starting and ending points of the motion: flexion-extension, radial-ulnar deviation and dart throwing motion angle. The orientation of the dart throwing motion plane relative to the flexion-extension axis ranged between 28° and 57° among the tested population. Plane orientations derived from optical motion capture differed from those calculated through goniometry by 25°. An equation to correct the estimation of the plane from goniometry measurements was derived. This was applied and differences in the orientation of the plane were reduced to non-significant levels, enabling the dart throwing motion to be measured using goniometry alone.

Psychometric properties of the goniometric assessment of the Dart Thrower’s Motion

Introduction

The Dart Thrower’s Motion is an important movement for hand function. A goniometric clinical measure of Dart Thrower’s Motion has been developed. However, its validity and reliability in people with wrist and hand injury is not known. This study investigated the inter-rater and test–retest reliability and criterion validity of the Dart Thrower’s Motion measure.

Methods

A cross-sectional design was used. Thirty-five participants with hand or wrist injury completed the goniometric assessment of the Dart Thrower’s Motion and goniometric wrist active range of motion assessment three times in a hand clinic. Two assessors and a reader to record the results were involved. Participants also completed the patient-rated wrist and hand evaluation.

Results

The intraclass correlation coefficients were 0.70–0.83 and 0.91–0.92, respectively for inter-rater and test–retest reliability in the injured hands indicating moderate to high reliability. The Pearson correlation coefficients between the Dart Thrower’s Motion measure and wrist active range of motion assessment ranged from 0.45 to 0.73, and with patient-rated wrist and hand evaluation ranged from −0.36 to −0.53. The results indicate that goniometric assessment of the Dart Thrower’s Motion has acceptable criterion validity.

Conclusion

The goniometric assessment of Dart Thrower’s Motion can be considered a valid and reliable clinical measure for measuring the impact of the injury to one’s hand and wrist range of motion and function. It shows its clinical utility in people with hand and wrist injury. It is hoped this simple measure can be eventually implemented in clinical settings, allowing for an increased understanding of an individual’s functional use of the hand and wrist.