Scapula

to identify the pattern of myoelectrical activity of muscles from the scapular region, after axillary lymphadenectomy in breast cancer. prospective cohort study including all the women submitted to axillary lymphadenectomy for surgical treatment of breast cancer, in a breast cancer reference center, from June to August 2006. The women were evaluated before, and after 3 and 12 months from the surgery, through physical and electromyographic examinations of the serratus anterior, upper trapezius and middle deltoid muscles. the patients' average age was 60.3 years old (DP+/-14.1), and the incidence of winged scapula at the physical examination was 64.9%. At the third-months evaluation, a reduction of 28.3 microV was observed in the myoelectrical activity of the serratus anterior muscle. At the twelveth-months evaluation and between the 3rd and the 12th month, there was an increment of 23.3 microV and 43.6 microV, respectively. For the upper trapezius, the increase was of 23.1 microV...

This study aimed to compare muscle activity in individuals with isolated acromioclavicular osteoarthritis (ACO), ACO associated with rotator cuff disease (ACO+RCD), and controls. Seventy-four participants (23 isolated ACO, 25 ACO+RCD, 26 controls) took part in this study. Disability was assessed with the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. Muscle activity of the upper trapezius (UT), lower trapezius (LT), serratus anterior (SA), and anterior deltoid (AD) was collected during arm elevation in the sagittal and scapular planes. Pain during motion was assessed with the numerical pain rating scale. Analysis of the DASH, pain and kinematics were reported in part 1 of this study. For each muscle, separate 2-way linear mixed-model ANOVAs were performed to compare groups. ACO+RCD group had more UT and AD activity than the the isolated ACO and control other groups, more AD activity than the isolated ACO group during the ascending phase, and more AD activity than t...

Bone loss in anterior glenohumeral instability occurs on both the glenoid and the humerus; however, existing biomechanical studies have evaluated glenoid and humeral head defects in isolation. Thus, little is known about the combined effect of these bony lesions in a clinically relevant model on glenohumeral stability. The purpose of this study was to determine the biomechanical efficacy of a Bankart repair in the setting of bipolar (glenoid and humeral head) bone defects determined via computer-generated 3-dimensional (3D) modeling of 142 patients with recurrent anterior shoulder instability. The null hypothesis was that adding a bipolar bone defect will have no effect on glenohumeral stability after soft tissue Bankart repair. Controlled laboratory study. A total of 142 consecutive patients with recurrent anterior instability were analyzed with 3D computed tomography scans. Two Hill-Sachs lesions were selected on the basis of volumetric size representing the 25th percentile (0.87 ...

Previous research has identified some specific exercises to correct scapular muscle balance and onset timing in healthy subjects. However, evidence for their effectiveness in overhead athletes with impingement symptoms has been lacking until now. A 6-week exercise program consisting of previously selected exercises is able to improve muscle activation and onset timing during shoulder elevation. This program may also change pain and functionality levels in overhead athletes with mild impingement symptoms. Case series; Level of evidence, 4. Forty-seven overhead athletes with mild impingement symptoms (25 men and 22 women) were enrolled in this study. Before and after the 6-week training program, the Shoulder Pain and Disability Index (SPADI) score was individually obtained and maximum voluntary isometric contraction (MVIC) values were determined by surface electromyography. Mean muscle activation levels, muscle ratio data, and muscle onset timing were assessed for the upper (UT), middle (MT), and lower (LT) trapezius and serratus anterior (SA) muscle during arm elevation in the scapular plane. Forty participants completed the exercise program. The SPADI scores significantly decreased from 29.86 ± 17.03 during initial assessment to 11.7 ± 13.78 during postmeasurements (P < .001). The 3 trapezius muscle parts showed increased MVIC values and decreased activation levels during arm elevation, whereas this was not the case for the SA muscle. After the training program, UT/SA significantly decreased, whereas UT/MT and UT/LT did not change (P < .05). No differences in muscle timing between pre- and postmeasurements could be identified. The LT showed significant earlier activation compared with UT (-0.47; P < .001) and MT (-0.49; P < .001). The serratus anterior showed significant earlier activation compared with the UT (-0.74; P < .001), MT (-0.76; P < .001), and LT muscles (F = 0.27; P = .046). This is the first longitudinal study to demonstrate that previously selected exercises (1) improve pain and function based on SPADI scores, (2) reduce relative trapezius muscle activation, and (3) alter UT/SA ratios. However, they were unable to change the timing of the scapular muscles during arm elevation when compared before and after a 6-week training program in overhead athletes with mild impingement symptoms.

The suprascapular notch (SSN) is the most common site of compression and injury of the suprascapular nerve (SN), which results in a neuropathy known as SN entrapment. The SSN is enclosed from the top by the superior transverse scapular ligament (STSL), creating a tunnel for the SN. On both sides of the SSN, below the STSL, the anterior coracoscapular ligament is found. This fibrous band can potentially narrow the opening and contribute to the occurrence of suprascapular entrapment syndrome. This study presents the first case of a bifid anterior coracoscapular ligament coexisting with an atypical SN course, which has never been described in the literature before. Knowledge of such anatomical variations can be helpful in arthroscopic and open procedures of the suprascapular region and confirms the safety of operative decompression for entrapment of the SN.

To quantify the electromyographic activity in the shoulder girdle musculature during ipsilateral kinetic chain exercises performed in a shoulder immobilizer in asymptomatic men. Descriptive. Motion analysis laboratory at a tertiary care center. Five asymptomatic male volunteers, ages 24 to 32 years. Fine-wire (supraspinatus, infraspinatus, upper subscapularis) and surface (deltoids, trapezii, biceps, serratus anterior) electrodes recorded electromyographic activity from each muscle during a split-stance cross-body rotation (twisting to the opposite side at high, mid, and low levels), split stance attempted ipsilateral floor touch, and attempted overhead reach. All movements were initiated from the immobilized scapula and were tested with and without a combined step. Mean peak normalized (percentage of maximum voluntary contraction [%MVC]) electromyographic activity of each muscle during each exercise. For all exercises, biceps and infraspinatus activity remained low (<10% MVC), whereas upper subscapularis activity was moderate to very high (29%-68% MVC). Supraspinatus activity was low (<20% MVC) for all motions except the attempted overhead reach (23% MVC). Serratus electromyographic activity was less than 20% of MVC for all motions and was most responsive to added stepping (23%-136% MVC without stepping vs 24%-199% MVC with stepping). Cross-body rotation at lower heights progressively increased serratus activity while decreasing supraspinatus, upper trapezius, and anterior deltoid activity. Based on these electromyographic data, selected kinetic chain exercises could potentially be implemented during periods of shoulder immobilization. All exercises examined could potentially be safe after superior labral anteroposterior repair, but not after subscapularis repair. All exercises, with the exception of the attempted overhead reach, could potentially be safe after supraspinatus repair, with or without concomitant infraspinatus repair. Early activation of the serratus anterior could potentially be achieved by performing cross-body rotations, particularly at lower heights.

The purpose of this study was to record the basic morphometric values of the acromion. Forty-four pairs of dried scapulas were reviewed. Acromial shape was evaluated in relation to sex, symmetry and presence of subacromial enthesophytes and classified according to Bigliani with the following results: type I (flat): 26.1%, type II (curved): 55.6% and type III (hooked): 18.1%. There was a greater percentage of type III in men (56.2% vs. 43.7%) and type I in women (56.5% vs. 43.4%). Acromial morphology was symmetric in 29 acromia (65.9%). Enthesophytes were most common in type III (75%). A rough inferior surface of the acromion was most frequently found in type III (81.2%). Nine other scapular osteological parameters were also measured. Many differences were noted between male and female scapulae. The great variety of morphological features is assumed to be related to rotator cuff pathology and other shoulder impairments.

Carrying heavy loads that compress the shoulders is a possible etiological factor for both accessory and long thoracic nerve entrapment. In our patient, shouldering heavy loads damaged both nerves. A 27-year-old right-hand-dominant man was referred because of difficulty in raising his arms after a brief period of painful episodes due to heavy load bearing on both shoulders. Atrophic muscles around the shoulders, depressed and winged scapula were noted. An EMG confirmed entrapment of long thoracic and accessory nerves. An exercise program was instituted; 16 months after initial referral, though winged scapula was still noted, manual muscular strength had returned without functional limitation.

The presence of a diarthrotic coracoclavicular joint, as represented by an articular facet on the conoid tubercle of the clavicle and the superior surface of the coracoid process of the scapula, was investigated. The sample consisted of 60 white and 180 black South African (60 Sotho, 60 Xhosa and 60 Zulu) skeletons. Each group consisted of 30 male and 30 female skeletons. The presence of the articular facet was recorded as either bilateral, unilateral left or unilateral right. The effect of clavicular length, scapular size and first rib angle on the presence of the coracoclavicular joint was also investigated. The presence of the articular facet was noted in 23 (9.6%) of the 240 individuals studied. Of these 23 individuals, 6 (26.1%) were white and 17 (73.9%) were black. Males (56.5%) presented a higher incidence of this anomaly than females (43.5%). The articular facet occurred bilaterally in 47.9% (11/23), unilaterally on the left in 30.4% (7/23) and unilaterally on the right in 2...

Aim To find out the predictors of scapula fractures in
high-impact blunt trauma patients and the predictors of
missing them in the emergency department (ED).
Methods This is a retrospective descriptive review of
patients treated at a single hospital over a 3.5-year period.
The study included 1,039 high-impact blunt trauma
patients of any age. The patients were divided into two
groups: patients with scapula fractures (the patient group)
and others (the control group). The patient group was reassessed
into two subgroups: patients with and without
missed scapula fractures. Logistic regression analysis was
used to assess the predictors of a scapular fracture in the
ED.
Results The incidence of scapula fractures was 4%. The
Injury Severity Scores (ISS) of the scapula fracture group
were significantly higher than those of the control group
(P\0.0001). Patients with scapula fractures were significantly
older (P\0.001). Patients with scapular body
fractures stayed for significantly longer in the intensive
care unit (ICU) (P = 0.039) and their mean Abbreviated
Injury Scale (AIS)face score was higher (P = 0.04) compared
to scapular fractures without body parts. Scapula
fractures were missed in 35.7% of patients. All bilateral
scapula fractures were missed. Computerized tomography
showing shoulder region or scapula was obtained in 26.7%
of missed injuries.
Conclusion After matching for ISS, the mortality of
patients with scapula fracture was significantly higher than
the control group. We observed that fractures in the glenoid
and scapular neck occurred higher than in the body region.
We found that the seniority of the ED doctor, consultation
ratio for orthopedics in ED, and the existence of brain
contusion were important parameters for missing scapula
fractures in ED.