Submaximal cardiopulmonary exercise testing to assess preoperative aerobic capacity in patients with knee osteoarthritis scheduled for total knee arthroplasty: a feasibility study

OBJECTIVE: To investigate the feasibility of submaximal cardiopulmonary exercise testing (CPET) in patients with knee osteoarthritis (OA) scheduled for primary total knee arthroplasty (TKA) surgery. Secondly, to assess their preoperative aerobic capacity. METHODS: In this observational, single-center study, participants performed a submaximal CPET 3-6 weeks before surgery. To examine their experiences, participants completed a questionnaire and one week later they were contacted by telephone. CPET was deemed feasible when five feasibility criteria were met. Aerobic capacity was evaluated by determining the oxygen uptake (VO2) at the ventilatory anaerobic threshold (VAT) and oxygen uptake efficiency slope (OUES). OUES values were compared with two sets of normative values. RESULTS: All feasibility criteria were met as 14 representative participants were recruited (recruitment rate: 60.9%), and all participants were able to perform the test and reached the VAT. No adverse events occurred, and all participants were positive toward submaximal CPET. The median VO2 at the VAT was 12.8 mL/kg/min (IQR 11.3-13.6). The median OUES/kg was 23.1 (IQR 20.2-28.9), 106.4% and 109.4% of predicted. CONCLUSION: Submaximal CPET using cycle ergometry seems feasible in patients with knee OA scheduled for TKA surgery to evaluate preoperative aerobic capacity

Is it possible to use the Structural Dimension Analysis of Motor Memory (SDA-M) to investigate representations of motor actions in stroke patients?

Braun SM, Beurskens AJ, Schack T, et al. Is it possible to use the Structural Dimension Analysis of Motor Memory (SDA-M) to investigate representations of motor actions in stroke patients? Clinical Rehabilitation. 2007;21(9):822-832.Objective: To determine the feasibility of the Structural Dimension Analysis of Motor Memory (SDA-M), a method derived from sports psychology, in establishing the mental representations of complex movements in patients after stroke. Design: Case series of patients, with age-matched healthy controls. Setting: A rehabilitation nursing home. Subjects: Sixteen patients 3-26 weeks after their stroke, and 16 controls. Intervention: Each control had the SDA-M performed within a 10-day period. Each stroke patient had the SDA-M performed once. In the SDA-M the subject was asked to state for each of 10 actions involved in drinking from a cup whether it is functionally close to each of the other nine or not. Main measures: The raw data from the SDA-M were transformed through cluster analysis into Euclidean distances and tree diagrams to illustrate the internal representation of the action. Results: All subjects were able to perform the assessment. Healthy controls all had a similar set of Euclidean distances and tree diagrams that were 'normal'. The tree diagrams remained very similar on the three occasions. Four stroke patients had tree diagrams that were 'normal'. The remaining twelve had tree diagrams that differed greatly both from the 'normal' and from each other, with much less clustering of actions. Patients with more severe stroke appeared to have more disordered tree diagrams. Conclusion: The Structural Dimension Analysis of Motor Memory (SDA-M) is a feasible method for investigating the mental representation of internal motor action plans in stroke patients, giving similar data in stable healthy people and revealing abnormal patterns in patients after stroke