Endocrine Abstracts

Acromegaly triggers, and is associated with, peripheral nervous system modifications and joint degenerations, which are considered to impact the walking balance of patients with acromegaly (PWA). Therefore, to better understand if these systemic degenerations impact the transitory adaptations in locomotor patterns of these patients, this study aims to establish the walking balance deficits of PWA. Walking balance was evaluated in PWA (n=8) in biochemical remission and a control group of patients with non-functioning pituitary adenomas (PNA, n=8). The groups were of similar age, sex, and BMI and all participants underwent surgery to remove the pituitary adenoma. Self-reported survey data was used to compare joint pain, functional disability scores, and history of joint surgery between groups. PWA reported significantly higher back, hip, and knee pain and greater functional disability of the hip and knee than PNA. However, the history of joint surgery did not significantly differ between groups. Walking balance was assessed using the Timed Up and Go (TUG) test, the Dynamic Gait Index (DGI) score, and muscle energy patterns during obstructed walking (10% leg length obstacle). The kinematics and kinetics of walking were calculated by measuring bipedal ground reaction forces and centre of pressure (COP) using two AMTI force plates with one underneath each foot. Lower limb kinematics were measured using a 7-body segment model with anatomical 3D positions recorded using a 14-camera OptiTrack motion capture system. Force plate and motion capture systems were synchronized and sampled at 200 Hz. Lower limb kinematics and kinetics were calculated using Visual 3D. The outcome measures of the study consisted of TUG time, DGI score, and differences in joint power during obstructed walking. PWA took more time to complete the TUG task but did not have a lower DGI score (ceiling effect). There was no significant difference found in obstructed walking speed or obstructed walking stride length between the PWA and PNA groups. The muscle energy pattern adaptations required for crossing obstacles show a possible trend with a decrease in frontal plane energy generation by the hip abductors of the support leg and sagittal plane energy absorption by the knee extensors of the passing leg. These findings suggest that PWA may employ a different strategy to control hip abduction when adapting to an obstacle compared to PNA. These results show that changes in the mechanics of walking in PWA may indicate a potential alteration in muscle activation strategies.