0
Research Papers

Assessment of Workspace Attributes Under Simulated Index Finger Proximal Interphalangeal Arthrodesis

[+] Author and Article Information
Paul G. Arauz

Manufacturing and Automation Laboratory,
Department of Mechanical Engineering,
Stony Brook University,
Stony Brook 11790, NY
e-mail: paul.arauz@stonybrook.edu

Sue A. Sisto

Professor
Rehabilitation Research and Movement
Performance Laboratory,
School of Health Technology and Management,
Stony Brook University,
Stony Brook 11794, NY
e-mail: sue.sisto@stonybrook.edu

Imin Kao

Professor
Manufacturing and Automation Laboratory,
Department of Mechanical Engineering,
Stony Brook University,
Stony Brook 11790, NY
e-mail: imin.kao@stonybrook.edu

1Corresponding author.

Manuscript received October 12, 2015; final manuscript received March 8, 2016; published online March 25, 2016. Assoc. Editor: Zong-Ming Li.

J Biomech Eng 138(5), 051005 (Mar 25, 2016) (11 pages) Paper No: BIO-15-1506; doi: 10.1115/1.4032967 History: Received October 12, 2015; Revised March 08, 2016

This article presented an assessment of quantitative measures of workspace (WS) attributes under simulated proximal interphalangeal (PIP) joint arthrodesis of the index finger. Seven healthy subjects were tested with the PIP joint unconstrained (UC) and constrained to selected angles using a motion analysis system. A model of the constrained finger was developed in order to address the impact of the inclusion of prescribed joint arthrodesis angles on WS attributes. Model parameters were obtained from system identification experiments involving flexion–extension (FE) movements of the UC and constrained finger. The data of experimental FE movements of the constrained finger were used to generate the two-dimensional (2D) WS boundaries and to validate the model. A weighted criterion was formulated to define an optimal constraint angle among several system parameters. Results indicated that a PIP joint immobilization angle of 40–50 deg of flexion maximized the 2D WS. The analysis of the aspect ratio of the 2D WS indicated that the WS was more evenly distributed as the imposed PIP joint constraint angle increased. With the imposed PIP joint constraint angles of 30 deg, 40 deg, 50 deg, and 60 deg of flexion, the normalized maximum distance of fingertip reach was reduced by approximately 3%, 4%, 7%, and 9%, respectively.

FIGURES IN THIS ARTICLE
<>
Copyright © 2016 by ASME
Topics: Kinematics , Design
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 3

The active ROM of the MCP and DIP joints of the index finger when the PIP joint is UC and constrained to selected angles of 0 deg, 20 deg, 30 deg, 40 deg, 50 deg, and 60 deg of flexion

Grahic Jump Location
Fig. 1

(a) Schematic illustration of the articulated index finger segment model. The 2D WS of the PIP joint constrained finger model described in Eq. (1). The parameters are as follows: l1 = 42 mm, l2 = 23 mm, and l3 = 19 mm. The ROM for θ2 and θ4 are: −30 ≤ θ2 ≤ 90 deg and 0 ≤ θ4 ≤ 80 deg. The PIP joint constraint angle is: θ3 = 60 deg. The 2D WS boundaries are represented by curves C1, C2, C3, and C4. The WS area, perimeter, and the maximum distance of fingertip reach are: Ac = 2870 mm2, pc = 308 mm, and Dc = 76 mm, respectively. Note that the perimeter, pc, is calculated by adding the lengths of curves C1, C2, C3, and C4. (b) An initial posture of reference angles of the equivalent kinematic model of the index finger. Note that the length of the UC finger is given by L = l1 + l2 + l3.

Grahic Jump Location
Fig. 2

Finger postures with 9.5 mm spherical markers attached and the PIP joint splinted. The 80 mm light-extension frame with two markers attached to the fingertip prevented marker occlusion during finger motions. Finger postures during task performance: (a) full extension of the MCP and DIP joints, and (b) full flexion of the MCP and DIP joints.

Grahic Jump Location
Fig. 4

The experimental 2D WS boundaries when the PIP joint is UC (gray circles) and constrained (gray dots). The black solid line shows the 2D WS boundaries C1, C2, C3, and C4 of the finger model. The model used a constant (average of all subjects) ROM of the joints. The parameters are as follows: l1 = 44 mm, l2 = 26 mm, and l3 = 18 mm. The ROM for θ2 and θ4 are: −30 ≤ θ2 ≤ 90 deg and 0 ≤ θ4 ≤ 80 deg. Model and experimental constrained areas are: (a) 2178 and 1260 mm2, (c) 2908 and 2729 mm2, and (d) 2908 and 2315 mm2, with the PIP constrained angle at 0 deg, 40 deg, and 60 deg of flexion, respectively. Experimental (gray dots) and model (black solid line) angles of the MCP (θ2) joint plotted on the horizontal axis, and those of the DIP (θ4) joint on the vertical axis of a rectangular coordinate system during generation of the WS boundaries C1, C2, C3, and C4 for one subject with the PIP constrained to: (b) 0 deg, (d) 40 deg, and (f) 60 deg of flexion.

Grahic Jump Location
Fig. 5

The design indices: (a) pertaining to the WS area, IA; (b) pertaining to the WS aspect ratio, Ia; and (c) pertaining to the maximum distance of fingertip reach, ID, of the constrained finger with experimental data of all subjects

Grahic Jump Location
Fig. 6

Comparison of design indices of the constrained finger between the experimental data of one subject (subject no. 4) and model prediction. The parameters of the model are as follows: l1 = 44 mm, l2 = 26 mm, and l3 = 18 mm. The ROM for θ2 and θ4 are:−30 ≤ θ2 ≤ 90 deg and 0 ≤ θ4 ≤ 80 deg.

Grahic Jump Location
Fig. 7

The weighted-sum criterion, f in Eq. (10), as a function of the PIP joint angle θ3, for different sets of αi. The experimental measurements and theoretical prediction are presented in (a) and (b), respectively.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In