Hand kinematics in osteoarthritis patients while performing functional activities

PURPOSE

To identify the impact of kinematic limitations on hand osteoarthritis patients' ability to perform daily living activities.

METHODS

An experiment was performed on 33 patients and 32 healthy subjects. Active ranges of motion (AROM) of 16 hand joint angles were measured, together with scores of different hand tests of dexterity (Box and Block, Nine Hole Peg, Kapandji) and function (Sollerman Hand Function Test, SHFT). Functional ranges of motion (FROM) were recorded during SHFT tasks. Results by task are also reported.

RESULTS

Patients' AROM is limited in flexion of thumb carpometacarpal and interphalangeal, and finger metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints, and in palmar arch. Patients scored worse in gross dexterity and opposition, but only Kapandji score was correlated with AROM limitations. Pain is mostly reported in patients with limited extension of finger MCP and PIP joints. Patients used significantly different FROM in almost all the joints, and needed more time to accomplish the SHFT tasks.

CONCLUSIONS

AROM measurements can be used as indicators for early diagnosis. Patients use specific strategies to accomplish each task, arising from AROM limitations; some tasks with very extreme postures. The tasks where precision or force are required for thumb are the most affected ones.Implications for rehabilitationActive range of motion is an indicator for early hand osteoarthritis diagnosis.Patients' functional ranges are reduced, and thumb opposition and gross dexterity are hindered.Rehabilitation should focus especially on tasks requiring precision and thumb strength.Rehabilitation should favor the improvement of task completion times.

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.

Complex thumb motions and their potential clinical value in identifying early changes in function

BACKGROUND

Early diagnosis and treatment of osteoarthritis of the thumb allows for early interventions that may mitigate osteoarthritis progression and decrease severity later in life. Early identification of motion changes is limited by the clinical reliance on single planar measurements using goniometry. Multi-planar measurements using motion capture can provide insights into joint function and pathophysiology that cannot be obtained from single-plane goniometry measurements. Thus, the goals of this research were 1) to determine differences in thumb motions across three groups of participants (young healthy (n = 23), older healthy (n = 11), and those with carpometacarpal osteoarthritis (n = 24)) and 2) to determine if multi-planar motions provided additional movement information in comparison to standard planar measures.

METHODS

In this study, a motion capture system was used to collect standard clinical ranges of motion and complex multi-planar tasks. Differences in motion patterns due to aging and osteoarthritis were identified. Motions tested included palmar adduction-abduction, radial adduction-abduction, metacarpophalangeal flexion-extension, interphalangeal flexion-extension, functional adduction-abduction, opposition, and circumduction.

FINDINGS

Results indicated that motion capture was capable of detecting changes in carpometacarpal mobility that were not detected using standard approaches. Our results suggested that use of multi-planar measurements have the potential to identify changes that are indicators of early stages of osteoarthritis.

INTERPRETATION

Early indicators are clinically useful as they will enhance patient treatment by permitting the application of treatment approaches sooner, potentially leading to reduced overall functional deficits.

Mapping Together Kinetic and Kinematic Abilities of the Hand

Millions of people have reduced hand function; this loss of function can be due to injury, disease, or aging. Loss of hand function is identified as reduced motion abilities in the fingers or a decrease in the ability of the fingers to generate force. Unfortunately, there are limited data available regarding each finger's ability to produce force and how those force characteristics vary with changes in finger posture. To relate motion and force abilities of the fingers, first, an approach to measure and map them together is needed. The goal of this work was to develop and demonstrate a method to quantify the force abilities of the fingers and map these forces to the kinematic space associated with each finger. Using motion capture and multiaxis load cells, finger forces were quantified at different positions over their ranges of motion. These two sets of data were then converted to the same coordinate space and mapped together. Further, the data were normalized for the index finger and mapped as a population space model. The ability to quantify motion and force data for each finger and map them together will provide an improved understanding of the effects of treatments and rehabilitation, identifying functional loss due to injury or disease, and device design.

Evaluation of the controlled grip force exertion tasks associated with age, gender, handedness and target force level

INTRODUCTION

Force control of the hand is an essential factor for operating tools and moving objects. Therefore, a method for quantifying hand functionality more accurately and objectively is very important.

METHODS

The present study included 60 healthy participants (30 elderly and 30 young adults) to evaluate the effects of age, gender and target force levels on tracking performance. Tracking performance was quantified by measuring the difference between target force levels and exerted force.

RESULTS

Females exerted 59.6% of the maximum grip strength of males and the elderly group exerted 70.5% of maximum grip strength compared with the young group. The elderly group showed 3.1 times larger tracking error than the young group. There was a significant difference in females between the young and elderly groups, indicating age-related decline in hand function is more pronounced in females. The difference in grip force control ability between the elderly and young groups was significant at the low target force level (5% maximum voluntary contraction).

CONCLUSIONS

The results of this study could be used for hand function evaluation guidelines. In addition, this study could be used as a tool for physiotherapy to improve hand function and prevent its decline in elderly people.

On redundancy resolution of the human thumb, index and middle fingers in cooperative object translation

Redundancy in motion, and synergy in neuromuscular coordination provides significant versatility to the human fingers while performing coordinated grasping and manipulation tasks in several ways. This paper explores how humans may resolve the redundancy in their thumb, index and middle fingers when these digits flex to cooperatively translate a small object toward the palm. It is observed that humans actively employ a secondary subtask of maximizing instantaneous manipulability that helps determine all intermediate finger configurations when performing the primary subtask of following a tip trajectory. This behavior is accurately captured by an inverse kinematic model based on aredundancyparameter. The joint angles get determined unambiguously though the redundancy parameter is shown to depend on the instantaneous finger configurations and also, to attain negative values. Further, this parameter is noted to vary significantly across subjects performing the same kinematic task. The findings, that are based on the experimental finger motion data garnered from 12 subjects, are reckoned to be of significant importance, especially in reference to the challenges in design and control of finger exoskeletons for cooperative manipulation.

Workspace Shape and Characteristics for Human Two- and Three-Fingered Precision Manipulation

GOAL

To study precision manipulation, which involves repositioning an object in the fingertips and is used in everyday tasks such as writing and key insertion, and also for domain-specific tasks such as small scalpel cuts, using tweezers, and hand soldering.

METHODS

In this study, the range of positions (workspace) through which 19 participants manipulated a 3.3-4.1 cm-diameter object are measured with a magnetic tracker. Each participant performed two conditions: a two-finger thumb-index finger condition and a three-finger thumb-index-middle finger condition.

RESULTS

The observed workspaces, normalized to a 17.5 cm hand length, are small compared to free-finger trajectories; for the two-finger trials, 68% of points are within 1.05 cm of the centroid and 95% are within 2.31 cm, while the three-finger case shows a narrower distribution, with 68% of points within 0.94 cm of the centroid and 95% of points within 2.19 cm. The longest axis is a long thin arc in the proximal-palmar plane. Analysis of fingertip workspaces shows that the index fingertip workspace volume is the most linear predictor of object workspace (R(2) = 0.98).

CONCLUSION

Precision manipulation workspace size and shape is shown, along with how the fingers are used during the manipulation.

SIGNIFICANCE

The results have many applications, including normative data for rehabilitation, guidelines for ergonomic device design, and benchmarking prosthetic and robotic hands.