# A Retrospective Clinical Analysis of Pain and Spasticity Outcomes Following Gravity-Support Exoskeleton Therapy in Chronic Stroke

## TL;DR

This study compared the effects of a gravity-support exoskeleton and conventional therapy on pain and mobility in chronic stroke patients, finding both improved outcomes but no significant difference between the two.

## Contribution

The study provides a clinical comparison of exoskeleton therapy and conventional rehabilitation for chronic stroke pain and spasticity.

## Key findings

- Both therapies significantly reduced post-stroke pain and improved motor function.
- The exoskeleton modestly reduced spasticity but showed no significant advantage over conventional therapy.
- Quality-of-life improvements were inconsistent across patients.

## Abstract

Background: Post-stroke pain (PSP), particularly shoulder pain, is frequent and often underdiagnosed, limiting rehabilitation adherence and functional recovery. Current pharmacological and physical treatments offer only partial relief. Robotic-assisted therapy (RAT), such as the gravity-supporting Armeo® Spring exoskeleton, delivers intensive, task-specific training with visual 2D feedback that may also alleviate PSP while enhancing motor outcomes. This study investigates whether RAT performed with the Armeo® Spring reduces upper-limb PSP in chronic stroke patients versus conventional therapy and evaluates its effects on motor function and functional independence. Methods: In this retrospective parallel group study, 32 chronic post-stroke patients (8 females and 24 males with a mean age of 57 ± 11.74) were allocated to two groups: 16 received upper-limb RAT with the Armeo® Spring, a gravity-supporting exoskeleton, (RAT group) and 16 underwent conventional rehabilitation (CR). The RAT group completed one-hour sessions 6 days/week for 8 weeks, performing 2D/3D gamified tasks targeting shoulder, elbow and forearm movements. The CR group received an equivalent amount of standard therapy, including passive/active-assisted mobilization, Bobath-based neuromuscular facilitation and reaching exercises. Results: Both the Armeo® Spring and conventional therapy groups showed significant reductions in post-stroke pain (RAT p < 0.001 and conventional rehabilitation p = 0.004) and improvements in upper-limb motor function and functional independence (both p ≤ 0.002). Spasticity in the impaired limb decreased modestly in the RAT group (p = 0.031), with no significant between-group differences in pain or spasticity change (p = 0.437; p > 0.05, respectively). Conclusions: Gravity-support exoskeleton training reduced upper-limb spasticity, and no statistically significant between-group differences were observed compared with conventional physiotherapy for pain, mobility, and functional independence. Although clinical outcomes improved, health-related quality-of-life domains showed heterogeneous trajectories, underscoring the complexity of perceived health changes during chronic stroke rehabilitation. Larger randomized controlled trials incorporating neurophysiological and kinematic endpoints and longer follow-up are warranted to confirm effectiveness, particularly in chronic stroke and durability.