Abstract P6-08-03: Incidence of winged scapula after breast cancer surgery with axillary dissection - Preliminary results

Abstract

Abstract Background: The axillary dissection during breast cancer surgery can cause a condition known as Winged Scapula. This condition, which may affect shoulder mobility, occurs when an injury to the long thoracic nerve weakens the serratus anterior muscle. Therefore, we conducted this study to determine the incidence of Winged Scapula and its impact on shoulder mobility. Method: We included patients with breast cancer and surgical indication for axillary dissection in a prospective study in the Gynecological Department of São Paulo Federal University. We excluded women with pre-surgery winged scapula, neurological diseases, orthopedic shoulder problems, comprehension difficulties and those undergoing autologous tissue reconstructions. We physically evaluated 84 patients before the surgery and again fifteen days after. We used the Hoppenfeld test (present or absent) to assess Winged Scapula incidence, the lateral scapular slide test (asymmetry - yes or no) to assess scapular position, and the 4-type method to assess scapular dyskinesia. In addition, we used a goniometer for flexion, extension, adduction and abduction to measure shoulder range of motion (ROM). Finally, patients indicated their level of pain using a scale from 0 to 10. Results: The McNemar test was used to statistically analyze the incidence of Winged Scapula and scapular asymmetry. Winged Scapula incidence was 7.1% with a 95% confidence interval ranging from 1.6% to 12.6% (p = 0.041). The lateral scapular slide test showed no statistical significance, which means the surgery did not cause scapular asymmetry. Scapular dyskinesia was analyzed through the Wilcoxon Signed Rank Test. There was no statistically significant evidence that surgery caused scapular dyskinesia (p = 0.904). We used the Paired T-Test to compare pre and post-operative shoulder ROM and pain. Flexion, adduction and abduction shoulder ROM presented a statistically significant reduction (p = 0.000). Respectively, the mean reductions were 34.19o (SD = 27.34), 6.6o (SD = 11.04) and 37.23o (SD = 33.09). Extension was the only movement without a significant change in range (p = 0.0156). Reported pain increased significantly after surgery (p = 0.003), from 1.476 (SD = 3.024) to 2.702 (SD = 2.853). A two-way Analysis of Variance (ANOVA) compared the ROM of the patients with Winged Scapula to those without. In ANOVA, a p > 0.05 indicates that there is no statistically significant difference in the way both groups vary. In this analysis both groups showed the same patter over time in all movements; flexion (p = 0.242), extension (p = 0.187), adduction (p = 0.096) and abduction (p = 0.793). Therefore, patients with Winged Scapula showed the same pattern of ROM reduction as patients without. Conclusion: We found that the axillary dissection during breast cancer surgery caused Winged Scapula 7.1% of the time, and that there was no relationship between the surgery and scapular asymmetry and dyskinesia. Furthermore, this surgical procedure also reduced shoulder ROM (flexion, adduction and abduction) and increased pain fifteen days after surgery. Finally, we could find no evidence that Winged Scapula led to a smaller shoulder ROM in recent post-operative physical analysis. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-08-03.