Clinical reasoning in cognitive rehabilitation therapy.

BACKGROUND: Many who provide cognitive rehabilitation therapy (CRT) are unaware of the theoretical rationale that underlies their decisions concerning therapeutic intervention. Can the survivor form goals for treatment? When should treatment end? When should the therapist retrain skills, provide remedial cognitive treatments, or simply adapt surroundings because a survivor is too handicapped to be treated at all? OBJECTIVE: This paper combines theory with the author's experience to provide therapists with a structure for clinical reasoning in their daily practice. METHOD: The discussion begins with a description of different models of recovery after brain injury. It goes on to discuss similarities, commonalities, and general principles that can be derived from all of them. It ends with suggestions for treatment that serve as useful guidelines for therapists in their practices. CONCLUSION: Combining the clinician's clinical intuition with knowledge of the theory of CRT can greatly improve the quality of treatment the therapist provides.

Physical strain and mechanical efficiency in hubcrank and handrim wheelchair propulsion.

The physical strain and mechanical efficiency of manual wheelchair propulsion using handrim and hubcrank propelled racing wheelchairs were studied during a submaximal wheelchair exercise test on a stationary roller ergometer. Ten healthy male able-bodied subjects conducted two exercise tests in a random order and measurements of phyical strain (oxygen uptake, minute ventilation, respiratory exchange ratio, heart rate) and gross mechanical efficiency were obtained. During the experiment torque data, speed and power output were determined at a sample frequency of 0.1 Hz. Analysis of variance for repeated measures (p < 0.05) was used to establish differences. The hubcrank propulsion mechanism showed a significantly lower physical strain and higher gross mechanical efficiency in comparison with the handrim propulsion mechanism. The lower strain and higher efficiency in propelling the hubcrank partly seems to be due to the continuous biphasic cyclic propulsion movement, which allows both push and pull forces to be exerted. This involves flexor and extensor muscles around elbow and shoulder, leading to a reduced tendency to fatigue in individual muscles in the upper extremity. The more natural and neutral wrist-hand orientation also seems to diminish finger flexor activity and wrist-stabilizing muscle activity, and will thus reduce physical strain both with respect to the cardiorespiratory and musculoskeletal systems. The latter may influence the tendency to develop carpal tunnel problems positively. The reduced strain of the hubcrank propulsion mechanism clearly has a number of advantages over handrims for the human engine in the short and long run. However, technical innovation should address current practical problems of steering and braking. Clearly, hubcranks can be used in low-seated wheelchairs (i.e. racing wheelchairs) only, and in subjects with a sufficiently large range of motion in the upper extremity. Moreover, the increased width is a drawback of hubcranks. Care should be taken while negotiating door posts.