Quantitative evidence of kinematics and functional differences in different graded trigger fingers

Comparison of finger kinematics between patients with hand osteoarthritis and healthy participants with and without joint protection programs

STUDY DESIGN

This is a cross-sectional, clinical observational study.

BACKGROUND

Finger range of motion (ROM) and functional performance are critical in many daily activities. Hand osteoarthritis (H-OA) is a prevalent disease that impairs both variables. Little quantitative research has been performed on finger kinematics during activities of daily living (ADLs) across health status and method of performance (with or without joint protection programs).

PURPOSE

The purpose of this research is to examine the effects of H-OA and method of performance on ROM in the thumb, index, and middle digits (flexion/extension and abduction/adduction) during ADLs.

METHODS

This study was conducted using 10 healthy participants (mean age: 28 years) and nine participants with H-OA (mean age: 72 years). All participants performed baseline ROM movements followed by 9 activities of daily living. These activities involved prehension type grasps and were performed with and without the recommended joint protection procedures specific to each task. Thumb IP and MCP, index distal interphalengeal (DIP) and proximal interphalengeal (PIP), and middle DIP and PIP joints were continuously recorded using an electromagnetic tracking system for ROM analysis.

RESULTS

Participants with H-OA had a statistically significant decrease in ROM when comparing values measured in the healthy cohort during active ROM (25° decrease) and ADL ROM (25° decrease) in the flex/ext direction. Similarly, following joint protection instruction, a statistically significant decrease in ROM was found during tasks in the flex/ext direction (healthy participant decrease in ROM: 17°, H-OA decrease in ROM:10°) CONCLUSIONS: This study demonstrated that people with hand arthritis move through a smaller arc of motion when performing some functional tasks as compared with the controls, and that with instruction on joint protection techniques, participants made significant changes in the amount of movement used to perform tasks, which supports a proof of principle of joint protection.

A method for measuring in vivo finger kinematics using electromagnetic tracking

Accurate in vivo measurement of finger joint kinematics is important for evaluation of treatment methods, implant designs, and for the development and validation of computer models of the hand. The main objective of this project was to develop a standardized finger kinematic measurement system employing electromagnetic (EM) tracking to measure in vivo finger motion pathways. A landmark digitization protocol was developed and used in vivo, in a biomechanical study using EM trackers secured to the finger segments. In vivo results for finger flexion/extension showed no significant differences between EM and goniometer results, 5°±3°; p = 0.735.

A Finite Element Model for Trigger Finger

The aim of this study was to develop a finite element model to investigate the forces on tendons which ensue due to trigger finger. The model was used to simulate both flexor and extensor tendons within the index finger; two test cases were defined, simulating a “mildly” and “severely” affected tendon by applying constraints. The finger was simulated in three different directions: extension, abduction and hyper-extension. There was increased tension during hyper-extension, with tension in the mildly affected tendon increasing from 1.54 to 2.67 N. Furthermore, there was a consistent relationship between force and displacement, with a substantial change in the gradient of the force when the constraints of the condition were applied for all movements. The intention of this study is that the simulation framework is used to enable the in silico development of novel prosthetic devices to aid with treatment of trigger finger, given that, currently, the non-surgical first line of treatment is a splint.

Effectiveness of proximal interphalangeal joint-blocking orthosis vs metacarpophalangeal joint-blocking orthosis in trigger digit management: A randomized clinical trial

STUDY DESIGN

Patients with Green's classification grade 2 or 3 A1-pulley trigger digit (TD) were recruited and randomized to receive the proximal interphalangeal joint-blocking orthosis (PIPJ-BO) or metacarpophalangeal joint-blocking orthosis (MCPJ-BO).

INTRODUCTION

TD is a common hand condition that can affect one's performance in activities of daily living. Conservative management of TD involves prescription of orthoses to facilitate recovery. No studies have evaluated the effectiveness of PIPJ-BO, optimal orthosis wear regime, and other factors affecting orthotic effectiveness.

PURPOSE OF THE STUDY

To compare the effectiveness of PIPJ-BO vs MCPJ-BO in TD management.

METHODS

Outcome measures included pain numerical rating scale, Green's classification grading, and Quick Disability of the Arm, Shoulder and Hand. Orthosis wear duration was also collated. Patients were followed up for 2 months, and changes between initial and final assessment score within each group and between both groups were analyzed.

RESULTS

Thirty-five patients with 43 TD were included in final analysis. Twenty-three TD were allocated PIPJ-BO while 20 with MCPJ-BO. Pain reduction was observed in both groups, but reduction was greater in PIPJ-BO group (P = .02). About 47.83% in PIPJ-BO group and 40% in MCPJ-BO group improved by at least 1 Green's classification grade. There was only significant improvement in Quick Disability of the Arm, Shoulder and Hand score for PIPJ-BO group (P = .0007), and duration of orthosis wear was significantly longer in the PIPJ-BO group (P = .0010). Advancing age was found to have higher rate of orthosis failure.

DISCUSSION

Findings suggest that both orthoses are effective in reducing pain and disability and improve in triggering symptoms, with PIPJ-BO being more superior. Moreover, PIPJ-BO is less restrictive, has better cosmesis and allowed better functional performance than MCPJ-BO.

CONCLUSION

PIPJ-BO is more effective than MCPJ-BO in pain reduction and achieved better functional outcome. Orthosis wear of 24 hours for more than 8 weeks is recommended.

Outcomes of Corticosteroid Treatment for Trigger Finger by Stage

BACKGROUND

Although steroid injection remains a common first-line treatment of trigger finger, clinical experience suggests that not all cases of trigger finger respond the same. The purpose of this study was to use a classification system for trigger finger that is simple and reproducible, and produces clearly definable, clinically relevant cutoff points to determine whether responsiveness to steroid injection correlates to clinical staging.

METHODS

The authors conducted a prospectively collected longitudinal study of trigger finger patients separated into four stages of severity. Each subject received a single injection of 6 mg of dexamethasone acetate. One-month outcomes were analyzed to evaluate the efficacy of steroid injection. These outcomes were further stratified based on baseline characteristics and stage of triggering.

RESULTS

A total of 99 digits and 69 subjects were included. Two variables were found to be significant in predicting response to initial injection: (1) multiple affected digits and (2) stage severity. Patients with multiple involved fingers were 5.8 times more likely to have no resolution of symptoms compared with those with a single affected finger. For every level of stage increase, the odds doubled for having no resolution of symptoms.

CONCLUSIONS

Steroid injection remains a viable first-line option for patients presenting with mild triggering (stage 1 and 2). For more severe triggering (stage 3 and 4) or multiple affected digits, the success of steroid injection is significantly lower at 1 month. For the latter patients, surgery may be a more reasonable initial treatment.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Dynamic Functional Assessment of Hand Motion Using an Animation Glove: The Effect of Stenosing Tenosynovitis

BACKGROUND

The aim of the present study is to determine whether an animation glove can be utilized to provide a reliable and reproducible assessment of dynamic hand function and whether this assessment is altered in the setting of hand pathology.

METHODS

Ten subjects without known hand pathology and 11 subjects with known stenosing tenosynovitis were assessed on tasks involving hand function at varied speeds, including forceful and gradual making of a fist and the quick and slow grip of a baseball using an animation glove to record range of motion and measures of velocity (CyberGlove II).

RESULTS

In normal subjects, peak extension and flexion velocity of the index and middle finger was highest in the metacarpophalangeal and lowest in the distal interphalangeal; however, the converse was true in the ring finger. In those subjects with stenosing tenosynovitis, the animation glove was able to detect a triggering event during assessment. Furthermore, there was a significant decrease in the maximum velocity of the proximal interphalangeal joint observed with the slow fist task in both flexion and extension (55%, P < .01) in the affected hand when compared with the unaffected hand.

CONCLUSIONS

The CyberGlove II can be utilized in the dynamic functional analysis of the hand and is able to detect a triggering event in subjects with known stenosing tenosynovitis. Those subjects demonstrate a significant decrease in maximum velocity in slow fist tasks, highlighting the need for comprehensive assessment to ascertain the full extent of functional limitations that can occur in the setting of hand pathology.

Evaluating Hand Function in Clients with Trigger Finger

Background

Trigger finger (TF) is a common hand pathology frequently encountered in hand clinics. Occupational therapists predominantly assess TF symptoms as opposed to using standardized hand functioning assessments. The purpose of this study was to assess the construct validity of dexterity and grip strength assessments for clients with TF.

Method

Sixty-three participants with TF and 66 healthy controls were administered the Functional Dexterity Test (FDT), Purdue Pegboard Test (PPT), and Jamar® Hydraulic Hand Dynamometer (JD) and completed the Disabilities of Arm Shoulder and Hand questionnaire (DASH). TF symptoms were graded using the Quinnell classification.

Results

Statistically significant differences were found between the groups in dexterity and grip strength. A statistically significant difference between the three TF grades was found on the PPT. All three test scores were moderately correlated with the DASH scores.

Conclusion

This study provides innovative evidence for the validity of common hand function assessments for individuals with TF and recommends incorporating these tools in clinical practice. Further research is needed with larger samples and better representation of each TF clinical grade.

Stenosing flexor tenosynovitis: Validity of standard assessment tools of daily functioning and quality of life

STUDY DESIGN

Cross-sectional.

INTRODUCTION

Stenosing flexor tenosynovitis (SFT) is a common hand disease, yet there is a lack of valid standard assessments for this population.

PURPOSE OF THE STUDY

Validation of assessment for the evaluation of disability and quality of life related to SFT clinical severity.

METHODS

Sixty five participants with SFT were matched to 71 controls. Participant's symptoms were graded using the Quinnell classification. Disability and quality of life were evaluated using the DASH and WHOQOL-BREF questionnaires.

RESULTS

Small to moderate correlations were found between SFT grade and the DASH and WHOQOL-BREF. Both questionnaires differentiated between the first and third clinical grades and between SFT and healthy groups.

DISCUSSION

Both questionnaires are useful tools to distinguish between participants with SFT and controls and between mild and severe clinical grades.

CONCLUSION

The DASH and WHOQOL-BREF may be implemented in the clinical management and research of SFT.

LEVEL OF EVIDENCE

Diagnostic III.

Using the international classification of functioning to examine the impact of trigger finger

PURPOSE

To evaluate the impact of trigger finger (TF) on hand motor function, activity and participation (A&P) and quality of life (QOL), and to evaluate the association between personal factors (age and gender, disease severity) and body functions (dexterity and strength) with A&P and QOL in patients with TF.

METHODS

Sixty-six patients with TF (study group) and 66 healthy volunteers (control group) participated in the study. TF symptoms were graded using the Quinnell classification. A&P was evaluated using the Disabilities of Arm Shoulder and Hand questionnaire and the QOL using the World Health Organization Quality of Life questionnaire. Dexterity was evaluated using the Functional Dexterity Test and the Purdue Pegboard Test; hand strength was evaluated using the Jamar Dynamometer and Pinch Gauge.

RESULTS

The comparisons between the study and control groups revealed significant differences in all measures. The study group reported lower perceived QOL, A&P and reduced hand strength and dexterity. Hierarchical regression analyses revealed that (a) the severity of TF contributed significantly to the explained variance of QOL, while demographics and hand functioning did not; (b) demographics, TF severity and hand function all contributed significantly to the explained variance of A&P.

CONCLUSION

The findings of the study point to the importance of addressing the functional implications and QOL of individuals with TF. Implications for Rehabilitation Although trigger finger is considered to be a mild hand pathology, it has a wide-ranging impact on hand functioning, daily activities and quality of life. Clinicians should include assessments of these outcomes in the treatment of individuals with trigger finger. Treatment efficacy should be evaluated with International Classification of Functioning outcomes, and not limited to symptomatology.

Finger movement function after ultrasound-guided percutaneous pulley release for trigger finger: effects of postoperative rehabilitation

OBJECTIVE

To develop and test a postoperative rehabilitation protocol for use by individuals with trigger finger undergoing ultrasound-guided percutaneous pulley release.

DESIGN

Nonrandomized controlled trial.

SETTING

Hospital and local community.

PARTICIPANTS

Individuals suffering from trigger finger with joint contracture (N=21) were recruited and grouped into an intervention group (n=9) or a control group (n=12).

INTERVENTIONS

All the participants underwent the same surgical procedure performed by the same surgeon. A 4-week postoperative rehabilitation program was designed based on the wound healing process. The intervention group received postoperative rehabilitation after the surgery, whereas the control group received no treatment after the surgery.

MAIN OUTCOME MEASURES

The finger movement functions were quantitatively evaluated before and 1 month after the surgery using a 3-dimensional motion capture system. The fingertip workspace and joint range of motion (ROM) were evaluated while the participant was performing a sequential 5-posture movement, including finger extension, intrinsic plus, straight fist, full fist, and hook fist.

RESULTS

The intervention group demonstrated significantly more improvements than the control group in the fingertip workspace (49% vs 17%), ROM of the distal interphalangeal (DIP) joint (16% vs 4%), ROM of the proximal interphalangeal (PIP) joint (21% vs 5%), and total active ROM (17% vs 5%).

CONCLUSIONS

This pilot study evaluated a postoperative rehabilitation protocol for trigger finger and demonstrated its effects on various finger functions. Participants who underwent the rehabilitation program had significantly more improvements in the fingertip workspace, ROM of the DIP and PIP joints, and total active ROM.

Clinical and pathological correlates of severity classifications in trigger fingers based on computer-aided image analysis

Background

The treatment of trigger finger so far has heavily relied on clinicians’ evaluations for the severity of patients’ symptoms and the functionality of affected fingers. However, there is still a lack of pathological evidence supporting the criteria of clinical evaluations. This study’s aim was to correlate clinical classification and pathological changes for trigger finger based on the tissue abnormality observed from microscopic images.

Methods

Tissue samples were acquired, and microscopic images were randomly selected and then graded by three pathologists and two physicians, respectively. Moreover, the acquired images were automatically analyzed to derive two quantitative parameters, the size ratio of the abnormal tissue region and the number ratio of the abnormal nuclei, which can reflect tissue abnormality caused by trigger finger. A self-developed image analysis system was used to avoid human subjectivity during the quantification process. Finally, correlations between the quantitative image parameters, pathological grading, and clinical severity classification were assessed.

Results

One-way ANOVA tests revealed significant correlations between the image quantification and pathological grading as well as between the image quantification and clinical severity classification. The Cohen’s kappa coefficient test also depicted good consistency between pathological grading and clinical severity classification.

Conclusions

The criteria of clinical classification were found to be highly associated with the pathological changes of affected tissues. The correlations serve as explicit evidence supporting clinicians in making a treatment strategy of trigger finger. In addition, our proposed computer-aided image analysis system was considered to be a promising and objective approach to determining trigger finger severity at the microscopic level.

Occupation-based assessments and treatments of trigger finger: a survey of occupational therapists from Israel and the United States

The purpose of this study was to describe the reported evaluation and treatment methods commonly administered by occupational therapy (OT) specialists in hand therapy for patients with trigger finger (TF). Sixty-one therapists from Israel and the United States completed an electronic survey. Sixty-nine per cent of the therapists reported evaluating TF symptoms (body function level) as part of their assessment protocol; however, only 25% reported the use of occupation-based measures for the assessment of people with TF. All therapists reported using orthoses to treat TF, yet significant differences were found between the groups regarding the frequency of using physical agent modalities, exercise and activity modifications. The results of the study point to the limited use of occupation-based assessments and to a lack of consensus regarding treatment guidelines for TF. The study is limited by a restricted sample size and a low response rate from US therapists, which warrant caution in generalization of the findings. Further research is needed to study the broad implications of TF in order to inform the assessment of TF in OT and to establish the foundations for future treatment efficacy studies.

One digit interruption: the altered force patterns during functionally cylindrical grasping tasks in patients with trigger digits

Most trigger digit (TD) patients complain that they have problems using their hand in daily or occupational tasks due to single or multiple digits being affected. Unfortunately, clinicians do not know much about how this disease affects the subtle force coordination among digits during manipulation. Thus, this study examined the differences in force patterns during cylindrical grasp between TD and healthy subjects. Forty-two TD patients with single digit involvement were included and sorted into four groups based on the involved digits, including thumb, index, middle and ring fingers. Twelve healthy subjects volunteered as healthy controls. Two testing tasks, holding and drinking, were performed by natural grasping with minimal forces. The relations between the force of the thumb and each finger were examined by Pearson correlation coefficients. The force amount and contribution of each digit were compared between healthy controls and each TD group by the independent t test. The results showed all TD groups demonstrated altered correlation patterns of the thumb relative to each finger. Larger forces and higher contributions of the index finger were found during holding by patients with index finger involved, and also during drinking by patients with affected thumb and with affected middle finger. Although no triggering symptom occurred during grasping, the patients showed altered force patterns which may be related to the role of the affected digit in natural grasping function. In conclusion, even if only one digit was affected, the subtle force coordination of all the digits was altered during simple tasks among the TD patients. This study provides the information for the future studies to further comprehend the possible injuries secondary to the altered finger coordination and also to adopt suitable treatment strategies.

Quantifying catch-and-release: the extensor tendon force needed to overcome the catching flexors in trigger fingers

The extensor tendon forces required to overcome the catching flexors in trigger fingers are unknown. A biomechanical model with moment equilibrium equations and method of least squares was developed for estimating the tendon force at triggering in trigger fingers. Trigger fingers that exhibited significant catching and sudden release during finger extension were tested. A customized "pulling tester" was used to pull the finger from flexion to extension and provide synchronic measurement of the pulling force. The displacement of the tested finger was measured by a motion capture system. This preliminary study presents kinematic and kinetic data at triggering of 10 trigger fingers. The distal and proximal interphalangeal (PIP) joints presented sudden release while the metacarpophalangeal (MCP) joint started extension in the early phase of finger extension. The tendon tension of flexor digitorum profundus was greater than that of flexor digitorum superficialis (FDS) in six fingers, and less than that of FDS in three fingers. The tension of two flexor tendons was almost equal in one finger. At the PIP and MCP joints, 1.54 times the force of flexors was needed for the extensors to overcome the catching flexors in trigger fingers. This biomechanical model provides clinicians with a clearer idea of the tendon force at triggering. The quantitative results may help in the understanding of movement characteristics of trigger fingers. These findings are useful to better understand the etiology and nature of trigger finger development, and thus aid in further development of better assessments and treatments related to this.

Manipulability analysis of human thumb, index and middle fingers in cooperative 3D rotational movements of a small object

The combined motion of the human thumb, index and middle fingers while rotating a small object across the extended, intermediate and flexed planes with respect to the fingers was analyzed. Auto reflective markers were attached on the fingers to track their motion across three postures and planes via a 3D motion capture system. Central, right and left rotation postures were considered in each plane for investigation and the rotation experiments were performed with 30 healthy subjects. The obtained data were used to compute the finger joint angles. Based on the three criteria of (i) manipulability measure, (ii) major axis direction angle of the manipulability ellipsoid and (iii) ratio of the minor over major axis lengths, the collective behavior of the fingers was studied. It has been found after analysis that the thumb and middle finger were active, while the index finger operated passively when manipulating small objects in cooperative rotational motion across the three planes. Activeness refers to the independence of a digit in controlling the motion of an object whereas passiveness denotes its dependence on other digits. An active finger governs the motion of an object whereas a passive finger simply supports it. The results of this investigation are of great importance in planning treatment for rehabilitation and for designing controllers for robotic therapists, finger exoskeletons and prostheses.

A retrospective review to determine the long-term efficacy of orthotic devices for trigger finger

PURPOSE

To evaluate the use of orthotic devices (splints) in an attempt to resolve trigger finger.

METHODS

Data were extracted from 46 charts during a five-year period from January 2005 to December 2010. At ten weeks, patients were seen for follow-up assessment of pain and stage of stenosing tenosynovitis (SST). One-year follow-up was performed to determine if the patients required further surgical intervention or steroid injection. The data were analyzed to determine the efficacy of orthosis intervention.

RESULTS

Mean pain score preorthotic is 5.63 and postorthotic is 1.20. Mean SST score preorthotic is 3.93 and postorthotic is 1.21. There was an 87% (40 patients) success rate with the orthotic intervention; 4.3% (two patients) had surgery and 8.5% (four patients) received a steroid injection in the year after orthotic application.

CONCLUSION

This study demonstrated the efficacy of orthoses for the reduction of pain and SST score for patients who have trigger finger.

LEVEL OF EVIDENCE

3.