Inspiratory Muscle Performance Is Related to Seated Balance Function in People With Spinal Cord Injury: An Observational Study.

OBJECTIVE: To examine the relationship between inspiratory muscle performance (IMP) and functional sitting balance (FSB) in persons with chronic spinal cord injury (SCI). We hypothesized that a moderate correlation would be found between IMP and FSB and that individuals with better balance would have better IMP. DESIGN: The SCI-specific modification of the Function in Sitting Test (FIST-SCI) measured FSB. The IMP measures included (1) maximal inspiratory pressure (MIP), (2) sustained MIP (SMIP), and (3) inspiratory duration. Upper extremity motor score (UEMS) and level of injury (LOI) were taken from International Standards for Neurological Classification of Spinal Cord Injury examinations. Spearman correlational analyses assessed relationships among these factors in the sample (N=37). Mann-Whitney U tests explored differences between 2 comparison group pairs (tetraplegia group [TG] vs paraplegia group [PG]; independent transfer group [ITG] vs assisted transfer group [ATG]). Regression analysis examined variables predictive of FSB in the TG. SETTING: Research facility. PARTICIPANTS: Volunteers with tetraplegia (n=21, American Spinal Injury Association Impairment Scale (AIS) A=8, B=7, C=6) and paraplegia (n=16, AIS A=9, B=4, C=3) (N=37). INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: IMP, LOI, UEMS, FIST-SCI. RESULTS: UEMS, MIP, SMIP, and LOI had moderate to high correlations with FIST-SCI scores (ρ=0.720 (P<.001), 0.480 (P=.003), 0.467 (P=.004), 0.527 (P=.001), respectively). UEMS, MIP, and FIST-SCI scores were higher in the PG and ITG than the TG and ATG, respectively (PG vs. TG P values=<.001, .008, .002, respectively, and ITG vs. ATG P values=<.001, .032, <.001, respectively). Further, SMIP and UEMS predicted FIST-SCI balance scores in the TG, accounting for 55% of total variance (P<.001) (FIST-SCI=11.88+0.03 [SMIP]+0.425 [UEMS]). CONCLUSIONS: The relationship between IMP and balance appears preserved after SCI. FSB was predicted, in part, via UEMS and SMIP in the TG. Future research should focus on the effect of SCI-based breathing interventions on FSB.

Psychometric Testing and Clinical Utility of a Modified Version of the Function in Sitting Test for Individuals With Chronic Spinal Cord Injury.

OBJECTIVES: Seated balance (SB) is substantially compromised and greatly impacts the function of individuals living with a spinal cord injury (SCI). A clinically applicable criterion standard measure for SB does not exist for this population. Initial validation and reliability analysis of the Function in Sitting Test (FIST) in SCI has been published, but the authors of this study report that modifications to the tool may be necessary. This study aimed to explore the psychometrics and clinical utility of a modified version of the FIST to better measure SCI-specific functional tasks in sitting. DESIGN: The FIST was modified (FIST-SCI) by an expert panel and used by 2 graders to evaluate the SB of individuals with chronic SCI (cSCI) on 2 separate days. The Motor Assessment Scale item 3 (MAS-SCI) was included as a comparison measure. SETTING: Research facility. PARTICIPANTS: Individuals with cSCI longer than 1 year (N=38) participated in the study. Injury levels of individuals participating in this study spanned C1 to T10 (American Spinal Injury Association Impairment Scale A, 17 subjects; B, 12 subjects; and C, 9 subjects). Thirteen individuals required assistance to transfer. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Validity, reliability, internal consistency, sensitivity, specificity, and responsiveness. RESULTS: Validity testing found a moderate relationship between the MAS-SCI and the FIST-SCI (ρ, .522; P<.05). FIST-SCI scores distinguished individuals requiring assistance to transfer from those who were independent (t=4.51; P<.05). Inter- and intra-rater reliability were excellent (intraclass correlation coefficient (2,k)=.985 and .983, respectively) and internal consistency was excellent (α=.94). A FIST-SCI cutoff score of 45 or greater was 92% sensitive and specific in characterizing transfer ability. Standard error of the measure (1.3) and minimal detectable change (3.5) were similar to previous work. CONCLUSIONS: Initial validity of the FIST-SCI is reported, but further assessment is required. Reliability is excellent in the cSCI population. FIST-SCI scores provide clinical insight into the seated functional ability of individuals with cSCI.