Comparison of Shoulder Protraction Strength and Electromyography Activity of Serratus Anterior and Pectoralis Major in Subjects With or Without a Winged Scapula

The Incidence of Winged Scapula after Thoracic Cancer Surgery: A Prospective Cohort Study

BACKGROUND

 Lung cancer is the leading cause of cancer-related deaths, and surgery is still the first treatment of choice in early and locally advanced cases. One of the iatrogenic complications is the serratus anterior palsy, which could lead to a winged scapula (WS). Unfortunately, the incidence of this deficit in thoracic surgery is unclear. Our primary aim was to determine the incidence of WS in lung cancer patients in a single-center experience.

METHODS

 We conducted a retrospective analysis of prospectively collected data with patients eligible for oncological thoracic surgery from March 2013 until January 2014. A physical evaluation of the WS was performed pre- and postoperatively, at the discharge and after 1 year of follow-up.

RESULTS

 A total of 485 patients were evaluated; 135 (27.8%) showed WS. Longer operative time (p < 0.0001), type of surgery (p < 0.0001), lymphadenectomy (p < 0.0001), and neoadjuvant treatment prior surgery (p = 0.0005) were significantly related to the WS injury. Multivariable analysis showed that type of surgery was significantly associated with WS (p < 0.0001). After 1 year, 41.6% still had WS.

CONCLUSION

 The incidence of WS was similar to the literature. As WS incidence is underdiagnosed, assessment and correct education about possible deficits or impairments should be improved. Moreover, when a minimally invasive approach is not planned, it is a good clinical practice to discuss surgical strategies with surgeons to reduce this deficit.

Electromyographic analysis of shoulder-complex muscles performing overhead presses with dumbbell, kettlebell, and bottom-up kettlebell

INTRODUCTION

Kettlebell exercises, specifically the bottom-up grip, have become increasingly popular in training programs. The purpose of this research was to determine if a bottom-up kettlebell grip favorably alters the electromyography (EMG), activity in the medial deltoid (MD), serratus anterior (SA), and lower trapezius (LT), muscles compared to using a dumbbell or traditional kettlebell grip during overhead shoulder presses.

METHODS

Twenty-eight healthy, male, Division III collegiate baseball players (mean age = 19.8 ± 1.28 years) performed five overhead presses of equal weight, 11.34 kg (25 lbs), using a dumbbell (DB), kettlebell w/traditional grip (KB), and kettlebell held with a bottom-up grip (KBU).

RESULTS

For the MD, there was significantly greater EMG activity using the DB compared to KBU, but no significant differences between the DB and KB, or KB and KBU. For the SA, greater EMG activity was noted using the KBU compared to KB, and KBU compared to DB, but no differences between KB and DB. For the LT, greater EMG activity was noted using the DB compared to KB, but no differences between DB and KBU, or KB and KBU.

CONCLUSION

The KBU press only elicited greater EMG activity in the SA. The DB elicited greater EMG activity in both the MD and LT. Shoulder-complex EMG activity varies with different types of overhead presses using equivalent loads.

Comparison of the Effects of Isometric Horizontal Abduction on Shoulder Muscle Activity During Wall Push-Up Plus and Wall Slide in Individuals With Scapular Winging

CONTEXT

Wall push-up plus (WPP) and wall slide (WS) are commonly prescribed in early rehabilitation to increase serratus anterior (SA) muscle activity. For individuals with scapular winging (SW), synergistic muscles such as upper trapezius (UT) and pectoralis major (PM) may compensate for weak SA during scapular movement. However, no studies have applied isometric horizontal abduction (IHA) during WS in individuals with SW nor have compared it with WPP with IHA.

OBJECTIVES

This study compared the effects of IHA on shoulder muscle activity during WPP and WS exercises in individuals with SW.

DESIGN

Cross-sectional study; 2-way repeated-measures analysis of variance was used to assess the statistical significance of observed differences in SA, UT, PM, lower trapezius (LT), and infraspinatus (IS) muscle activities.

SETTING

Research laboratory.

PATIENTS

We recruited 30 individuals with SW comprising 20 men and 10 women.

INTERVENTIONS

The individuals performed WPP and WS exercises with and without IHA using Thera-Band.

MAIN OUTCOME MEASURES

Surface electromyography was used to measure muscle activity of the SA, UT, PM, LT, and IS during the isometric phase of WPP and WS. Maximal voluntary isometric contractions were recorded to normalize electromyographic data.

RESULTS

There was no significant interaction between IHA application and exercise type for any of the shoulder muscles. IHA application increased SA (P = .008), UT (P = .001), LT (P = .009), and IS (P = .000) activities and decreased PM (P = .001) activity compared with those without IHA. WS exercises elicited higher PM (P = .017) and LT (P = .011) activities than WPP.

CONCLUSION

WPP and WS with IHA may be effective in increasing the muscle activities of shoulder stabilizers and preventing overactivation of PM activity. WPP may be recommended for individuals with overactivated PM, whereas WS may be used to increase LT activity.