BACKGROUND: This study was undertaken to evaluate the positional relationship between planes of the glenoid component (the scapular plane and the perpendicular plane to the glenoid) and its surrounding structures. METHODS: Computed tomography (CT) images of both shoulders of 100 patients were evaluated using the 3-dimensional CT reconstruction program (Aquarius®; TeraRecon). We determined the most lateral scapular bony structure of the scapular plane and measured the shortest distance between the anterolateral corner of the acromion and the scapular plane. The distance between the scapular plane and the midpoint of the line connecting the posterolateral corner of acromion and the anterior tip of the coracoid process (fulcrum axis) was also evaluated. The perpendicular plane was then adjusted to the glenoid and the same values were re-assessed. RESULTS: The acromion was the most lateral scapular structure of scapular plane and perpendicular plane to the glenoid. The average distance from the anterolateral corner of the acromion to the scapular plane was 10.44 ± 5.11 mm, and to the plane perpendicular to the glenoid was 9.55 ± 5.13 mm. The midpoint of fulcrum axis was positioned towards the acromion and was measured at 3.90 ± 3.21 mm from the scapular plane and at 3.84 ± 3.17 mm from the perpendicular plane to the glenoid. CONCLUSIONS: Our data indicates that the relationship between the perpendicular plane to the glenoid plane and its surrounding structures is reliable and can be used as guidelines during glenoid component insertion (level of evidence: Level IV, case series, treatment study).
Acromion ; Arthroplasty ; Humans ; Shoulder

No abstract available.
Acromioclavicular Joint* ; Acromion* ; Dislocations*

Rotator cuff injury and impingement syndrome have been thought to be related to the structure of acromion, such as subacromial distance, acromial type, acromial spur and acromial angle. Evaluation was done in 90 normal shoulders without impingement or rotator cuff injury, using shoulder X-ray series, composed of AP view, impingement view, and arch view. As results, 52(52.8%) of them had subacromial spur by the impingement views. The spur size was 12.4+/-4.5 mm and increased with age without statistical significance(p>0.05). The subacromial distance was 11.1+/-2.2 mm in AP view and 10.4+/-1.9 mm in arch view without statistical difference for age and sex(p>0.05). Among 90 normal shoulders, the acromion was quite often curved Type II, 51.1%, type I, 22.2%, and type III 26.7%. Mean acromial angle was 29.1 degrees in arch view and increased with age(p<0.05). Mean acromial tilt was 31.8 degrees without significant difference for age and sex(p>0.05). These results suggest their clinical relevance to the impingement syndrome and the rotator cuff injury.
Acromion ; Rotator Cuff ; Shoulder*

Isolated acromial fracture is not common and it frequently accompanies fractures to the coracoid process and glenoid bone and also injuries to the acromioclavicular joint. Furthermore, most of these combined acromial fractures have minimal displacement, which needs no additional treatment other than protection for a certain period of time. We have experienced a case of isolated fracture of the posterolateral angle of the acromion, which we reduced and fixated using K-wire and cannulated screws. We report on the technical aspects and clinical results of this reduction and fixation, along with a review of the literature.
Acromioclavicular Joint ; Acromion ; Displacement (Psychology)

Reverse total shoulder arthroplasty is one of the methods of surgical treatment for cuff tear arthropathy. Reverse total shoulder arthroplasty is increasingly being performed, but various complications have been reported. We experienced a case of acromion fracture after reverse total shoulder arthroplasty, which is quite a rare complication. So we report on this case along with reviewing the relevant literature.
Acromion ; Arthroplasty ; Fractures, Stress ; Shoulder

PURPOSE: The shape of the acromion was analyzed radiologically to assess the effect on rotator cuff tears. MATERIALS AND METHODS: The rotator cuff tear group consisted of 91 patients with a mean age 55.6 years (range, 27-85 years) and the normal shoulder articular disease (control) group consisted of 100 subjects with a mean age of 42.9 years (range, 18-72 years). The lateral extension of the acromion and the lateral acromial angle were measured on an oblique coronal MRI, and the anterior covering of the acromionon was measured on a supraspinatus outlet view. RESULTS: The lateral extension of the acrominon of the rotator cuff tear group of patients and the control group of subjects was 0.70+/-0.07 and 0.64+/-0.10, respectively. The lateral acromial angle was 72.6+/-6.5degrees and 76.4+/-6.5degrees, respectively, and the anterior covering of the acromion was measured to be 0.55+/-0.13 and 0.51+/-0.14, respectively. In a comparison with the control group of subjects, the lateral extension of the acrominon of the rotator cuff tear group of patients was larger and the lateral acromial angle was smaller; these findings were statistically significant (p<0.001). In addition, the correlation coefficients of the lateral extension of the acromion to the lateral acromial angle in the rotator cuff tear group of patients and in the control group of subjects was -0.44 and -0.46, respectively; a statistically significant correlation was seeen (p<0.001). CONCLUSION: The results suggest that the measurement of the lateral extension of the acromion and the lateral acromial angle determines the shape of the acromion, and thus it may represent a useful marker to confirm the interrelationship of a rotator cuff tear.
Acromion ; Humans ; Rotator Cuff ; Shoulder

We experienced acromial erosion and subsequent fracture after the treatment of Rockwood type V acromioclavicular dislocation with hook plate and coracoclavicular ligament augmentation. It was treated by using a surgical technique to address an acromial fracture and subsequent losses of reduction in acromioclavicular joint with two trans-acromial cortical screws (crossbar technique). The reduction state of acromioclavicular joint could be maintained by these two screws. Our crossbar technique could be considered as a good salvage procedure for the reduction loss caused by cutout or significant erosion of acromion after insertion of clavicular hook plate.
Acromioclavicular Joint ; Acromion ; Dislocations ; Ligaments

PURPOSE: We evaluated the correlation of the anatomic parameters of the acromion those represent on the magnetic resonance image (MRI) of impingement syndrome. MATERIALS AND METHODS: From June, 2004 to December, 2005, 71 cases were surgically proven to be impingement syndrome, and the anterior acromial hooking angle, the lateral acromial hooking angle (AAHA and LAHA) and the acromial hooking index (AHI: the sum of the AAHA and LAHA) were compared to 16 control cases. At the same period, 55 cases were surgically proven to be partial or full thickness rotator cuff tear, and age, gender and twelve anatomic parameters, including the acromial type, the acromial angle, the anterior covering, the acromial slope, the AAHA, the lateral acromial angle, the acromial torsional angle, the lateral acromial angulation, the LAHA, the lateral covering, the acromiohumeral distance and the AHI were assessed. RESULTS: The AAHA and AHI were increased as impingement syndrome proceeded. The acromial type and acromial angle, and the AAHA, LAHA and AHI showed significant differences between the controls and the rotator cuff tear patients on univariant analysis. On multivariant analysis, gender was most strongly correlated with rotator cuff tear. Age, AAHA and the acromial angle showed similar correlation, respectively. CONCLUSION: The coronal acromial shape is correlated with rotator cuff tear, and it is important to correct the lateral acromial shape when performing acromioplasty.
Acromion ; Humans ; Magnetic Resonance Spectroscopy ; Rotator Cuff

Supraspinatus outlet view and thirty-degree caudal tilt view have been used for the diagnosis of rotator cuff disease. Because scapula is moving on the thoracic cage, these two views are not always easy to take. The purposes of this study were to investigate the detectability of these views, to compare both views and to observe the interobserver reliability of these views. Supraspinatus outlet views and thirty-degree caudal tilt views were taken from 66 shoulders with clinically diagnosed rotator cuff disease. The shape of the acromions was examined on the supraspinatus outlet views and the size and shape of the acromions were analyzed on the thirty-degree caudal tilt views. An orthopaedic resident, an orthopaedic staff and a radiologic staff reviewed the all films without knowing the opinions of others. Suprapinatus outlet views were not-acceptable in average 43.9% and thirty-degree caudal tilt view were not-acceptable in average 12.6%. All of the three observes had same opinions in 43.9% for the supraspinatus outlet views, and in 45.5% for in thirty-degree caudal tilt views. Disagreement among all three observes was noticed in 13.6% for the supraspinatus outlet views and in 3.0% for in thirty-degree caudal tilt views. In the supraspinatus outlet views, the hooked acromions appeared in average 12.1%. In the thirty-degree caudal tilt view, acromial spurs appeared in average 27.3%. Only 2.5% in average showed hooked acromion on supraspinatus outlet view and acromial spur on thirty-degree caudal tilt view. Thirty-degree caudal tilt view is easier to take and more reliable than supraspinatus outlet view. In is better to take both supraspinatus outlet view and thirty-degree caudal tilt view for each patients with rotator cuff diseases. Radiologic findings should be judged on the base of clinical feature.
Acromion ; Diagnosis ; Humans ; Rotator Cuff ; Scapula ; Shoulder

Acromial fractures are well-documented complications subsequent to reverse shoulder arthroplasty (RSA), and most appear as stress fractures with no history of single trauma. To date, no study has reported the occurrence of acute displaced acromial fracture due to sudden strong deltoid contraction during heavy work. Displacement of the fracture results in a challenging surgery since it is difficult to obtain adequate fixation in thin and osteoporotic bones. We report a rare case of acute displaced acromial fracture after successful RSA treatment, using a novel technique of open reduction and internal fixation, applying two 4.5 mm cannulated screws and lateral clavicle precontoured plate.
Acromion ; Arthroplasty ; Clavicle ; Fractures, Stress ; Scapula ; Shoulder