Enhancement of a virtual reality wheelchair simulator to include qualitative and quantitative performance metrics.

The increasing importance of inclusive design and in particular accessibility guidelines established in the U.K. 1996 Disability Discrimination Act (DDA) has been a prime motivation for the work on wheelchair access, a subset of the DDA guidelines, described in this article. The development of these guidelines mirrors the long-standing provisions developed in the U.S. In order to raise awareness of these guidelines and in particular to give architects, building designers, and users a physical sensation of how a planned development could be experienced, a wheelchair virtual reality system was developed. This compares with conventional methods of measuring against drawings and comparing dimensions against building regulations, established in the U.K. under British standards. Features of this approach include the marriage of an electromechanical force-feedback system with high-quality immersive graphics as well as the potential ability to generate a physiological rating of buildings that do not yet exist. The provision of this sense of "feel" augments immersion within the virtual reality environment and also provides the basis from which both qualitative and quantitative measures of a building's access performance can be gained.

Distal ulnar growth arrest.

Four cases of arrest of distal ulnar physeal growth occurring in children ages 7 to 13 years had follow-up for 2 to 10 years. Each patient developed bowing of the radial diaphysis, ulnar translation of the distal radial epiphysis, and increased ulnar angulation of the distal radiocarpal joint surface. Growth discrepancies were documented in both the ulna (range 2.2 to 3.9 cm) and to a lesser extent the radius (range 0.2 to 1.6 cm) when compared to the opposite forearm in each patient. The progression of deformity appeared to be greatest during adolescence. Radial deviation and pronation were limited to varying degrees in each case. No patient had significant pain or functional impairment, but the cosmetic appearance was always displeasing. Indications for surgical treatment include increasing ulnar angulation of the distal radial articular surface, progressive loss of motion, and displeasing cosmetic appearance.