OBJECTIVETo investigate the relationship of the greater tuberosity and the lateral fin of the prosthesis by using cadaveric research.

METHODSNine pairs of fresh-frozen upper extremity specimens (n = 18) were collected. Two-part anatomical neck fracture models were created by osteotomy along the anatomical neck. A standardized humeral head replacement procedure was carried out. The prosthesis was implanted in 20 degrees and 40 degrees of retroversion respectively, and the distance between the bicipital groove and lateral fin of the prosthesis was measured.

RESULTSThe lateral fins of prostheses in all specimens were located behind the bicipital groove. The average distances were 7.3 mm in 20 degrees retroversion and 4.0 mm in 40 degrees retroversion.

CONCLUSIONIt is better to fix the greater tuberosity over the lateral fin during humeral head replacement.

Arthroplasty, Replacement ; methods ; Humans ; Humerus ; anatomy & histology ; surgery ; Shoulder Fractures ; surgery ; Shoulder Joint ; anatomy & histology ; surgery

Briefly discuss some recognation problems about acupuncture treatment of periarthritis of shoulder at present and put forward the methods for diagnosis and acupuncture treatment based on accurate location.
Acupuncture Therapy ; methods ; Humans ; Meridians ; Periarthritis ; therapy ; Shoulder Joint ; anatomy & histology ; physiology ; Shoulder Pain ; therapy

INTRODUCTIONDetailed anatomical knowledge of the suprascapular notch (SSN) is important for the management of entrapment neuropathy and interventional procedures. The objective of the present study was to collect data on the morphological features and anatomical variations of the SSN in an Indian population.

METHODSWe studied 268 human scapulae of unknown sex (126 right-sided, 142 left-sided) taken from the Department of Anatomy, Dayanand Medical College and Hospital, India. SSNs were classified as either type I, II, III, IV or V, based on the shape of the inferior border of the incisura, and comparison of the SSN's vertical and transverse diameters. The shape of the SSN (i.e V- or U-shaped), if present, was also recorded.

RESULTSType II SSN was the most common (50.00%), followed by type I, type IV and type III (32.46%, 9.70% and 7.84%, respectively). For right-sided type II SSNs, the transverse and vertical diameters were 9.1 ± 3.2 mm and 5.2 ± 1.9 mm, respectively, while those for left-sided type ll SSNs were 9.2 ± 2.4 mm and 5.1 ± 1.8 mm, respectively. Generally, the transverse diameter of type II SSN was found to be greater than that of type III SSN. The incidence of U-shaped SSN was 51.49%, while that of V-shaped SSN was 2.99%.

CONCLUSIONThis study of the morphometrical characteristics and anatomical variations of SSN provides an anatomical database of SSN in the Indian context. This database will be of use in surgical procedures, as the information can be used to ensure adequate access to and complete decompression of the suprascapular nerve.

Humans ; India ; Nerve Compression Syndromes ; diagnosis ; Scapula ; anatomy & histology ; surgery ; Shoulder Joint ; injuries

Acromioclavicular Joint ; anatomy & histology ; injuries ; surgery ; Fracture Fixation ; instrumentation ; methods ; Humans ; Male ; Shoulder Dislocation ; surgery

OBJECTIVETo explore the distribution rules of proximal and distal focus of muscle meridian region in scapulohumeral periarthritis.

METHODSThree hundred and six shoulder joints of affected side were selected in 216 patients of scapulohumeral periarthritis. Under the guidance of muscle meridian theory, with the anatomical characteristics of muscle meridian focuses, the frequency and location where proximal and distal focus appeared were calculated by palpation.

RESULTSThe percentages of the frequency that the focus of muscle meridian of Hand-Yangming, Hand-Shaoyang, Hand-Taiyang, and three yin meridians of hand appeared at proximal points of shoulder joint were 25.6% (1 146/5 657), 30.9% (1 749/5 657), 19.0% (1 075/5 657), and 24.5% (1 387/5 657), respectively, the focuses of muscle meridian region were Jianyuci, Juguci, Xiaoshuoci, Naohuici, etc. The percentages of the frequency that the focus of muscle meridian region appeared at distal points of shoulder joint were 31.77% (287/905), 23.2% (210/905), 10.9% (99/905), and 34.1% (304/905), the focuses of muscle meridian were Yangxici, Shousanlici, Yangchici, etc.

CONCLUSIONThe location and frequency of proximal and distal focus of muscle meridian in scapulohumeral periarthritis are closely related with the anatomical structure and biomechanical characteristics of the shoulder joints, thus new therapy for scapulohumeral periarthritis is implied.

Acupuncture Points ; Acupuncture Therapy ; Adult ; Aged ; Female ; Humans ; Male ; Meridians ; Middle Aged ; Palpation ; Periarthritis ; diagnosis ; therapy ; Shoulder Joint ; anatomy & histology

The motions of humeral external rotation with and without the anterior band of inferior glenohumeral ligament complex (AB-IGHL) were simulated. As a result of comparison, the contact pressure and contact force are all higher when the AB-IGHL was included in the model. Therefore, it is theoretically proved that the AB-IGHL constrains the motion of humerus during humeral external rotation. The predicted values for von Mises and the maximum tense force in the AB-IGHL were 4.433 MPa and 37.32 N respectively, occurring on the humeral side of the ligament. This approach to evaluating the function of AB-IGHL would provide greater insight into the mechanical contribution of AB-IGHL to joint function, identify the mechanism of a hurt to AB-IGHL, and provide a quantitative means for developing low-risk rehabilitation protocols.
Finite Element Analysis ; Humans ; Ligaments, Articular ; physiology ; Range of Motion, Articular ; Rotation ; Shoulder Joint ; anatomy & histology ; physiology ; Tensile Strength

We developed a three-dimensional finite element model of the shoulder glenohumeral joint after shoulder arthroplasty including humerus shaft, scapular, scapular cartilage and eight muscles, while each of the muscles was simulated with 50 spring elements. To reduce the element number and improve the analytical precision, we used mixed tetrahedral and hexahedral elements in the model. We then used the model to calculate the biomechanics of the shoulder glenohumeral joint after hemiarthroplasty during humeral external rotation. Results showed that the maximum joint reaction force was 374.72 N and the maximum contact stress was 6. 573 MPa together with the contact areas at 40 degrees external rotation. These might be one of the reasons for prosthetic disarticulation, and would provide theoretical bases to prosthetic design.
Biomechanical Phenomena ; Finite Element Analysis ; Humans ; Humeral Head ; anatomy & histology ; Models, Anatomic ; Prosthesis Design ; Range of Motion, Articular ; Rotation ; Shoulder Joint ; anatomy & histology

OBJECTIVETo investigate the in vivo and three-dimensional (3D) length changes of the glenohumeral ligaments during shoulder abduction using open magnetic resonance imaging (MRI).

METHODSFrom 2007 to 2008 3D attachment points of the glenohumeral ligaments were obtained by anatomical study and computed tomographic scanning of 10 embalmed cadaveric shoulders, including the superior glenohumeral ligament (SGHL), middle glenohumeral ligament (MGHL), the anterior band of the inferior glenohumeral ligament (AIGHL), axillary pouch and the posterior band of the inferior glenohumeral ligament (PIGHL). Then an in vivo study was conducted, in which 14 right shoulder joints of 14 healthy volunteers were evaluated in 7 isometric abduction positions (0 degrees , 30 degrees , 60 degrees , 90 degrees , 120 degrees , 150 degrees and 180 degrees ) using a noninvasive 3D motion-analysis system. 3D models of the shoulders and located the attachment points of the ligaments were created. Ligament lengths were based on the shortest calculated paths between each origin and insertion in 3D space along the 3D bone surface for each abduction position.

RESULTSDuring shoulder abduction, the 3D distance of SGHL was found to elongated and attained maximal length at 30 degrees abduction (P = 0.2). MGHL and AIGHL attained maximal length at 60 degrees (P < 0.05) and 120 degrees (P < 0.05) abduction, respectively. Pouch and PIGHL reached the maximal length at 180 degrees abduction (P < 0.05).

CONCLUSIONSThe SGHL limits inferior translation of the humeral head at 30 degrees of abduction. MGHL maintains maximum anterior stability at 60 degrees of abduction. AIGHL prevents anterior dislocation of the humeral head at 120 degrees of abduction. In 180 degrees abduction, pouch provided anterior stability and PIGHL has the contribution to the inferior stability.

Aged ; Aged, 80 and over ; Female ; Humans ; Imaging, Three-Dimensional ; Ligaments, Articular ; anatomy & histology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Models, Anatomic ; Shoulder Joint ; anatomy & histology

The purpose of this review was to demonstrate magnetic resonance (MR) arthrography findings of anatomy, variants, and pathologic conditions of the superior glenohumeral ligament (SGHL). This review also demonstrates the applicability of a new MR arthrography sequence in the anterosuperior portion of the glenohumeral joint. The SGHL is a very important anatomical structure in the rotator interval that is responsible for stabilizing the long head of the biceps tendon. Therefore, a torn SGHL can result in pain and instability. Observation of the SGHL is difficult when using conventional MR imaging, because the ligament may be poorly visualized. Shoulder MR arthrography is the most accurately established imaging technique for identifying pathologies of the SGHL and associated structures. The use of three dimensional (3D) volumetric interpolated breath-hold examination (VIBE) sequences produces thinner image slices and enables a higher in-plane resolution than conventional MR arthrography sequences. Therefore, shoulder MR arthrography using 3D VIBE sequences may contribute to evaluating of the smaller intraarticular structures such as the SGHL.
Adult ; *Breath Holding ; Female ; Humans ; Imaging, Three-Dimensional/*methods ; Ligaments, Articular/*anatomy & histology/pathology ; Magnetic Resonance Imaging/*methods ; Male ; Middle Aged ; Shoulder Impingement Syndrome/*diagnosis ; *Shoulder Joint/injuries ; Tendon Injuries/diagnosis

BACKGROUND: The aim of this study was to determine if there were significant differences in glenohumeral joint morphology between North American and East Asian populations that may influence sizing and selection of shoulder arthroplasty systems. METHODS: Computed tomography reconstructions of 92 North American and 58 East Asian patients were used to perform 3-dimensional measurements. The proximal humeral position was normalized in all patients by aligning it with the scapular plane utilizing anatomic landmarks. Measurements were performed on the humerus and scapula and included coronal and axial humeral head radius, humeral neck shaft and articular arc angles, glenoid height and width, and critical shoulder angle. Glenohumeral relationships were also measured and included lateral distance to the greater tuberosity and acromion, abduction lever arm, and acromial index. Parametric and nonparametric statistical analyses were used to compare population metrics. RESULTS: East Asian glenohumeral measurements were significantly smaller for all linear metrics (p < 0.05), with the exception of acromial length, which was greater than in the North American cohort (p < 0.001). The increase in acromial length affected all measurements involving the acromion including abduction lever arms. No difference was found between the neck shaft and articular angular measurements. CONCLUSIONS: The East Asian population exhibited smaller shoulder morphometrics than their North American cohort, with the exception of an extended acromial overhang. The morphologic data can provide some additional factors to consider when choosing an optimal shoulder implant for the East Asian population, in addition to creating future designs that may better accommodate this population.
African Americans/*statistics & numerical data ; Aged ; Anthropometry ; Asian Continental Ancestry Group/*statistics & numerical data ; European Continental Ancestry Group/*statistics & numerical data ; Female ; Humans ; Male ; Prosthesis Design ; Republic of Korea/epidemiology ; Shoulder/*anatomy & histology ; Shoulder Joint/*anatomy & histology ; Shoulder Prosthesis ; United States/epidemiology