Outcomes in transhumeral upper limb amputation with osseointegration and targeted muscle reinnervation: A preliminary observational cohort study.

Background: Little is known about outcomes associated with the combination of osseointegration (OI) and targeted muscle reinnervation (TMR) in upper limb amputation (ULA).

Objectives: To describe functional outcomes of three cases with OI and TMR who used myoelectric prostheses and compare outcomes to matched control groups.

Design: An observational cohort, quasiexperimental design with nonequivalent control groups was used. Wilcoxon Mann-Whitney and Fisher's exact tests compared outcomes between OI cases, control group 1 (six myoelectric/hybrid users without TMR or OI), and control group 2 (seven myoelectric/hybrid users with TMR but not OI). Hedges' g effect sizes (ES) were calculated.

Setting: Community dwelling adults.

Participants: U.S. veterans and civilians with transhumeral ULA.

Interventions: OI and TMR.

Main outcome measures: We employed 11 dexterity measures, 5 functional measures, 5 prosthesis satisfaction measures, 4 quality of life measures, 7 patient experience measures, 4 measures of prosthesis use, and 10 pain measures.

Results: Comparison 1: Cases had higher scores than controls on Brief Activity Measure for ULA (ES = 1.59; p = .08), Prosthesis Evaluation Questionnaire Residual Limb Health (ES = 1.54; p = .09), Patient Experience Measure Intuitiveness (2.33; p = .07), and h/d of prosthesis use (ES = 1.40; p = .09). Comparison 2: Cases had better prosthesis satisfaction as measured by the Trinity Amputation and Prosthesis Experience Satisfaction Scale (ES = 2.36; p = .05); Orthotics and Prosthetics User Survey Client Satisfaction with Devices (CSD) 8 (ES = -2.70; p = .08); CSD-W Comfort (ES = 3.51; p = .05); and the CSD-W Appearance (ES = 2.36; p = .09), higher scores of the Upper Extremity Functional Scale for Prosthesis Users One-handed Task scale (ES = 2.27; p = .05); the Modified Prosthesis Evaluation Questionnaire (PEQ) Residual Limb Health scale (ES = 1.95; p = .07); and Patient Experience Measure (PEM) Intuitiveness scales (ES = 2.28; p = .05). Cases had greater prosthesis use, measured by d/wk of wear, d/wk of use, h/d of wear, and h/d of use with ES ranging from 0.93 to 2.03 and p values from .05 to .08 for nonparametric tests.

Conclusion: Cases with OI and TMR reported better residual limb health, greater intuitiveness, and more hours of daily prosthesis use than controls. Further study with larger samples is warranted to investigate the additive benefit of both OI and TMR.