Muscular forces and joint angles in small-handed pianists: A pilot study on the 7/8 size keyboard versus the full size keyboard

This pilot study examined whether the use of a 7/8 keyboard contributed to the physical ease of small-handed pianists in comparison with the conventional piano keyboard. A secondary research question focused on the transition from one keyboard to the other. For the purposes of this study, we adopted David Steinbuhler's postulated hand span of 8 inches or less as defining a "small-handed" pianist. The goal was to measure muscle loading and hand span during performance of the excerpt. Data collection included each participant being monitored using electromyography via surface electrodes, which were attached to the upper back/shoulder, parts of the hand and arm, and the masseter muscle of the jaw. Subjects were also fitted with electrogoniometers to capture how the span from the first metacarpophalangeal (MCP) joint to the fifth MCP joint moved according to performance demands, as well as recording wrist flexion and extension, radial and ulnar deviation. The findings were that smallhanded pianists preferred the smaller keyboard and were able to transition smoothly between it and the conventional keyboard. The maximal angle of hand span while playing a difficult piece averaged about 5° smaller on the radial side and 10° smaller on the ulnar side for the 7/8 keyboard, leading to perceived comfort (ease) and better performance as rated by the subjects.