Impact of unilateral mastectomy on body posture: A prospective longitudinal observational study.

ABSTRACT

Objective: Unilateral mastectomy is known to induce postural alterations, yet the temporal development pattern of these changes remains elusive. This study aimed to explore the impact of unilateral mastectomy on body posture. Methods: A prospective, longitudinal, observational study with a one-group repeated-measures design was conducted. Patients undergoing unilateral mastectomy were recruited from a university-affiliated hospital in Western China and monitored for 12 months post-surgery. A trained nurse assessed seven postural baseline parameters on the day of suture removal and at 3, 6, and 12 months after unilateral mastectomy. Two parameters were in the sagittal plane (forward head posture and trunk rotation angle), and five were in the coronal plane (neck tilt, shoulder asymmetry, scapular asymmetry, scapular asymmetry relative to the spine, and pelvic tilt). Results: The final analysis included 159 patients. Baseline prevalence of most postural abnormalities ranged from 50.94% to 59.75%, with mean deviations between 2.74 and 4.51 mm. At 12 months post-mastectomy, prevalence and mean deviations increased by more than 30% and 3.50 mm, respectively, compared to baseline. Postural abnormalities increased gradually in the first 3 months, notably between the 3rd and 6th months, and slowed between the 6th and 12th months. On the mastectomy side, coronal plane abnormalities significantly increased within 12 months earlobe to acromion distance (Wald χ2 = 45.283, P < 0.001), depressed shoulder height (Wald χ2 = 42.253, P < 0.001), depressed scapula height (Wald χ2 = 31.587, P < 0.001), scapula to spine distance (Wald χ2 = 45.283, P < 0.001), and elevated pelvic height (Wald χ2 = 48.924, P < 0.001). Conclusions: Postural changes are common post-unilateral mastectomy, with prevalence and deviation increasing gradually, particularly between 3 and 6 months post-mastectomy. Early rehabilitation initiation is recommended to mitigate postural changes. Trial registration ChiCTR2000040897.