Peak Jump Power Reflects the Degree of Ambulatory Ability in Patients with Mitochondrial and Other Rare Diseases

Side alternating vibration training in patients with mitochondrial disease: a pilot study

Background

Side alternating vibration training (SAVT) is a mechanical oscillation using a vibrating platform that simulates exercise. We hypothesized that patients with mitochondrial myopathies, who experience muscle weakness, may see an improvement in muscle power with SAVT.

Methods

Patients with mitochondrial disease started either a treatment (SAVT) or control phase (standing without vibration) for 12 weeks, then 12 weeks of washout, and then a 12-week cross-over. The main outcome measure was peak jump power (PJP). We compared this to a natural history cohort from clinic.

Results

Seven out of 13 patients completed at least 80% of their SAVT sessions and were analyzed. The ΔPJP after the control phase was -2.7 ± 1.7 W/kg (mean ± SEM), SAVT was +2.8 ± 0.6 W/kg (p < 0.05) and from the natural history cohort was -2.4 ± 0.8 W/kg/year.

Conclusions

SAVT is well tolerated and may improve muscle power in mitochondrial disease patients.

Experience with jumping mechanography in children with cerebral palsy

OBJECTIVES

Jumping mechanography provides robust motor function indicators among healthy children. The aim of the study was to assess the reproducibility and validity of jumping mechanography conducted as single two-legged jump (S2LJ) in children with cerebral palsy (CP).

METHODS

215 S2LJ investigations from a sample of 75 children with CP were eligible for evaluation. For the estimation of the reproducibility, only the baseline set of data per patient were used. Gross motor function was evaluated by the Gross Motor Function Measure (GMFM-66). In 135 S2LJ investigations, GMFM-66 was assessed within a week in the same child. This data was used for validity assessment.

RESULTS

Coefficients of variation for the main outcome parameters ranged between 6.15-9.71%, except for jump height (CV%=27.3%). The intraclass correlation coefficients for peak velocity (V_max) and peak power relative to body weight (P_max/mass) was 0.927 and 0.931. V_max and P_max/mass were also the test parameters with the strongest correlation to the GMFM-66 score (⟩0.7).

CONCLUSIONS

S2LJ assessed in the present study provided reproducible outcome measures particularly for Vmax and Pmax/mass in children with CP. Further, V_max and P_max/mass showed the strongest correlation with the GMFM-66 score and seem to be the most relevant evaluation criteria.