# Instrumental Evaluation of the Effects of Vertebral Consolidation Surgery on Trunk Muscle Activations and Co-Activations in Patients with Multiple Myeloma: Preliminary Results

## TL;DR

This study investigates how vertebroplasty surgery affects trunk muscle activity in multiple myeloma patients, finding increased muscle activation post-surgery and highlighting the need for early rehabilitation.

## Contribution

The study provides preliminary evidence on the impact of vertebroplasty on trunk muscle activation and co-activation in multiple myeloma patients.

## Key findings

- Vertebroplasty increases trunk muscle activation and co-activation in multiple myeloma patients.
- Patients show higher muscle activity compared to healthy controls after surgery.
- Early rehabilitation is recommended to prevent excessive co-activation post-surgery.

## Abstract

Multiple myeloma (MM) patients complain of pain and stiffness limiting motility. To determine if patients can benefit from vertebroplasty, we assessed muscle activation and co-activation before and after surgery. Five patients with MM and five healthy controls performed sitting-to-standing and lifting tasks. Patients performed the task before and one month after surgery. Surface electromyography (sEMG) was recorded bilaterally over the erector spinae longissimus and rectus abdominis superior muscles to evaluate the trunk muscle activation and co-activation and their mean, maximum, and full width at half maximum were evaluated. Statistical analyses were performed to compare MM patients before and after the surgery, MM and healthy controls and to investigate any correlations between the muscle’s parameters and the severity of pain in patients. The results reveal increased activations and co-activations after vertebroplasty as well as in comparison with healthy controls suggesting how MM patients try to control the trunk before and after vertebroplasty surgery. The findings confirm the beneficial effects of vertebral consolidation on the pain experienced by the patient, despite an overall increase in trunk muscle activation and co-activation. Therefore, it is important to provide patients with rehabilitation treatment early after surgery to facilitate the CNS to correctly stabilize the spine without overloading it with excessive co-activations.