A new approach to characterize postural deficits in chemotherapy-induced peripheral neuropathy and to analyze postural adaptions after an exercise intervention

Abstract

Background Postural instability presents a common and disabling consequence of chemotherapy-induced peripheral neuropathy (CIPN). However, knowledge about postural behavior of CIPN patients is sparse. With this pilot study, we used a new approach to i) characterize postural impairments as compared to healthy subjects, ii) allocate possible abnormalities to a set of parameters describing sensorimotor function, and iii) evaluate the effects of a balance-based exercise intervention. Methods We analyzed spontaneous and externally perturbed postural control in eight CIPN patients before and after a balance-based exercise intervention by using a modification of an established postural control model. These findings were compared to 15 matched healthy subjects. Results Spontaneous sway amplitude and velocity were larger in CIPN patients compared to healthy subjects. CIPN patients’ reactions to external perturbations were smaller compared to healthy subjects, indicating that patients favor vestibular over proprioceptive sensory information. The balance-based exercise intervention up-weighted proprioceptive information in patients. Conclusions CIPN patients’ major postural deficit may relate to underuse of proprioceptive information that results in a less accurate posture control as spontaneous sway results indicate. The balance-based exercise intervention is able to partially correct for this abnormality. Our study contributes to a better understanding of postural impairments in CIPN patients and suggests an effective treatment strategy.

Type of exercise may influence postural adaptations in chemotherapy‐induced peripheral neuropathy

“…confirmed the assumption that poor balance performance in CIPN is related to the impaired interpretation of somatosensory information. In line with their study, we detected abnormally low use of proprioceptive cues in CIPN patients potentially interfering with effective posture control by evaluating perturbed stance and applying a model‐based analysis strategy in a pilot approach 19 . Then, we compared the postural behavior of eight CIPN patients to healthy control participants before and after 12 weeks of intervention (endurance, balance, and strength training).…”

“…Functional impairments and postural instability due to CIPN carry relevant health risks for affected patients 2,4,5,10 . While there are many reports about CIPN‐induced postural instability, 3,5,12,13,21,53 the underlying postural control mechanisms have barely been described 3,11,19,53 —in particular when it comes to characterizing different exercise effects 19 . The aim of the present exploratory study was, therefore, to quantify the exercise effect based on the set of abnormalities derived from comparing the quiet and perturbed stance of patients to healthy control participants via a model‐based analysis.…”

“…Only our aforementioned pilot study has so far identified relevant parameters responsible for postural adaptations in CIPN after exercising. There, we additionally implemented a balance‐based exercise intervention that induced a sensory shift toward the postural behavior of healthy control participants by up‐weighting proprioception despite CIPN 19 . This pilot approach had certain limitations (e.g., no patient control group, small sample size, multimodal intervention), 19 but it nevertheless formed the basis for the present study.…”

Cancer survivors post-chemotherapy exhibit unique proprioceptive deficits in proximal limbs

“…Increased visual dependency has been previously observed in cancer patients with CIPN during standing balance. Many postural studies reported a greater increase in postural sway in the absence of vision in cancer patients than that in healthy controls and attributed such changes to CIPN-related somatosensory de cits [22][23][24]. However, the type and location of the somatosensory de cits were often overlooked in these postural studies.…”

“…However, the type and location of the somatosensory de cits were often overlooked in these postural studies. Kneis et al [24] suggested involvement of proprioceptive dysfunction but did not specify the location of the de cits; others simply attributed the de cits to abnormal sensory symptoms in distal limbs (e.g., feet) without assessing the proximal joints [22,23].…”