Abstract
This thesis presents four studies focusing on outcomes of gait performance using gait analysis and/or the Six-minute-walk test (6MWT), in patients with post-polio syndrome (PPS). Further, resistance training in combination with Coenzyme Q10 (Q10) and intravenous immunoglobulin treatment (IvIg) in PPS patients was evaluated.
Study I was a test-retest reliability study where 23 PPS patients completed three 6MWT. Results of the study pointed to increased fatigue in later tests among patients who walked with walking aids. The intra-class correlation coefficient (ICC2.1) values were high indicating high reliability. The standard error of measurement (SEM) and the smallest real difference (SRD) were reasonably small implying that the 6MWT has acceptable sensitivity and can be used to detect real clinical changes in a group as well as in a single individual.
Study II aimed to investigate, with gait analysis, that is, 3-dimensional (3D) movement analysis during a clinical 6MWT, gait variables and the influence of fatigue, in 18 PPS patients compared to 11 healthy controls. The results indicated fatigability in the PPS group compared to the controls. A distinct plantar-flexed ankle at initial contact (IC) was seen in the PPS patients. However, the most striking finding of the study was related to the hip joint which, at foot-off (FO), was flexed in the patients while extended in the controls. The increased hip flexion at FO was negatively correlated with walking speed.
Study III was a randomized placebo-controlled study, evaluating the effect of resistance training combined with oral supplementation with Q10 in 14 patients with PPS. The result confirmed that muscle training leads to increased muscle strength, muscle endurance and mental health. There were, however, no statistically significant differences between the Q10 group and the placebo group for any of the evaluations.
Study IV evaluated the effects of treatment with IvIg on primarily gait ability, measured with 3D gait analysis, in 17 PPS patients. A sub-group performed a 12-week muscular resistance training programme. Walking distance and isometric knee flexion strength increased while hip- and knee flexion at FO decreased after the 12 weeks for all participants. IvIg, in combination with training, resulted in a further increase in walking distance as well as improved general health and less general fatigue.
In conclusion, the 6MWT is a reliable test for evaluating gait ability in PPS patients. One test may be enough for clinical purposes, but the best results of two tests can be used for research purposes. Compared to healthy controls, PPS patients walked with plantar-flexed ankle at IC and an increased hip flexion at FO. The latter negatively correlated with walking speed. Muscle training had positive effects in PPS patients regarding walking distance as well as muscle strength and mental health, with no added benefit from supplementation with Q10. Treatment with IvIg resulted in increased walking distances and isometric knee flexion strength as well as a decreased hip- and knee flexion at FO. An additional training programme had some further positive effects. However, whether muscle training enhances the effect of IvIg cannot be fully answered on the basis of the present data.
