03955562 is referenced by 13 patents and cites 4 patents.

The range of motion that an individual can move his head or other body portions can be measured and recorded in an apparatus having a base with a plurality of switches mounted thereto in a plurality of predetermined positions with each switch being actuated by movement of the base as the individual moves his particular body part through available angles in predetermined directions. The switches actuate a display board, having lights and/or a graph, to maintain a display of the available range of motion the individual can move his head or other body portion.

Title
Apparatus for measuring range of motion
Application Number
5/578549
Publication Number
3955562
Application Date
May 19, 1975
Publication Date
May 11, 1976
Inventor
Edward L Farrar Jr
1315 S. Orange Ave., Orlando, 32806
FL, US
Agent
Duckworth Hobby & Allen
IPC
A61B 5/10
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