OBJECTIVE: To evaluate magnetic resonance imaging (MRI) observer variability to detect ectopic insertion of the pectoralis minor tendon (EIPMT) and to investigate changes in the rotator interval in patients with EIPMT using MRI. MATERIALS AND METHODS: A total of 507 shoulder MRIs (male:female = 259:248; mean age, 55.4 years) were classified into 1) normal type insertion of the pectoralis minor tendon, 2) complete type EIPMT, and 3) partial type EIPMT independently by two radiologists. Inter-observer agreement was calculated using the kappa coefficient. Thickness of the fibrotic scar tissue in the subcoracoid triangle and humeral side axillary recess was measured. MRIs were reviewed by consensus with regard to the grade of fibrotic scar tissue proliferation in the rotator interval. Comparisons were made between normal and EIPMT and between partial and complete type EIPMT. RESULTS: The incidence of EIPMT was 13.4% (complete type, 7.7%; partial type, 5.7%). Inter-observer agreement was substantial (kappa = 0.775). Fibrotic scar tissue in the subcoracoid triangle was thicker, and the grade of fibrotic scar tissue proliferation in the rotator interval was higher in the EIPMT group than those in the control group. No significant difference was observed in the thickness of humeral side axillary recess. The thicknesses of fibrotic scar tissue in the subcoracoid triangle and humeral side axillary recess as well as the grade of fibrotic scar tissue in the rotator interval were not significantly different between complete and partial type EIPMT. CONCLUSION: MRI enabled detection of EIPMT with substantial observer agreement. Patients with EIPMT show a high tendency for fibrotic scar tissue proliferation in the rotator interval.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Female ; Humans ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; Rotator Cuff/pathology/*radiography ; Shoulder/pathology/radiography ; Tendons/pathology/*radiography ; Young Adult

OBJECTIVE: To correlate the acromiohumeral distance (AHD) using tomosynthesis and rotator cuff (RC) pathology and various anatomical indices and to assess the diagnostic reproducibility of tomosynthesis for the evaluation of subacromial impingement. MATERIALS AND METHODS: A retrospective review of 63 patients with clinically suspected subacromial impingement was conducted. Two musculoskeletal radiologists independently measured the following quantitative data: the AHD on plain radiographs and the AHD at three compartments (anterior, middle, and posterior) using tomosynthesis, computed tomography (CT) arthrography, or magnetic resonance (MR) arthrography. To investigate the association between the AHD and RC pathology and various anatomical indices, we reviewed the arthroscopic operation record as the referenced standard. RESULTS: The size of rotator cuff tear (RCT) in full-thickness tears displayed a significant inverse correlation with the middle and the posterior tomosynthetic AHDs (p < 0.05). The results of an ANOVA revealed that the middle tomosynthetic AHD retained a significant association with the type of RCT (p = 0.042), and the posterior tomosynthetic AHD retained significance for the size of RCT in a full-thickness tear (p = 0.024). The inter-modality correlation exhibited significant agreement especially among the plain radiography, tomosynthesis, and CT or MR arthrography (p < 0.05). The intraobserver and interobserver correlation coefficients (ICCs) displayed excellent agreement (ICC = 0.896–0.983). The humeral head diameter and glenoid height were significantly correlated with patient height and weight. CONCLUSION: Acromiohumeral distance measurement using tomosynthesis is reproducible compared with other modalities.
Arthrography ; Humans ; Humeral Head ; Pathology ; Radiography ; Retrospective Studies ; Rotator Cuff* ; Shoulder ; Tears

The role of acromioclavicular (A-C) arthritis in stage 2 and 3 impingement syndromes was investigated in this study. Twenty-seven patients with stage 2 and 3 impingement syndrome were evaluated both clinically and radiologically for the presence of A-C arthritis. Patients with A-C arthritis who were treated by conservative or surgical methods were rated before and after therapy according to the University of California at Los Angeles (UCLA) shoulder rating scale. The follow-up period ranged from 7 to 16 months, with an average of 13 months. A-C arthritis was diagnosed in 21 of 27 patients (one grade 2 and 20 grade 3, according to Kellegren). Clinical and radiological evaluation of these 21 patients revealed A-C joint pain and a positive lidocaine injection test in all (100%), a positive horizontal adduction test in 20 (95.2%), decreased joint space in 18 (85.75%) and osteophytes in 11 (52.4%). Surgical treatment was considered for 12 A-C arthritis patients; and distal clavicle resection was performed in 11 of these cases. The average score measured by the UCLA rating scale increased from 13 to 28 in the group treated with surgery (satisfactory result), and from 10 to 13 in the group treated with conservative therapy (unsatisfactory result). The results of this study may be interpreted as demonstrating that A-C arthritis is a common etiologic factor in chronic impingement syndromes and its co-existence has a strategic importance in the choice of treatment method. Surgical resection of the distal clavicle should be considered in the presence of this pathology since this technique provides excellent results in pain relief and appears to be superior to conservative therapy in these cases.
Acromioclavicular Joint*/radiography ; Acromioclavicular Joint*/pathology ; Adult ; Aged ; Arthritis/radiography ; Arthritis/pathology ; Arthritis/complications* ; Arthrography ; Cartilage, Articular ; Human ; Male ; Middle Age ; Shoulder Impingement Syndrome/complications*

BACKGROUND: The prevalence of os acromiale has been documented to be between 1% and 15% and is known to be clinically associated with subacromial impingement or rotator cuff tear. However, the prevalence of os acromiale in Korea has not yet been determined. The purpose of this study is to evaluate the prevalence of os acromiale in Korean patients who visited shoulder clinics and to investigate the correlations with rotator cuff tear. METHODS: We retrospectively reviewed the X-rays of patients visiting a shoulder clinic at a tertiary hospital in Korea from January 2011 to January 2012 to determine the frequency of os acromiale. X-ray findings were confirmed with magnetic resonance imaging (MRI) for patients who had these images available. MRI was also used to assess the status of the rotator cuff. The correlation between the presence of os acromiale either with gender, hand dominance or rotator cuff tear was analyzed statistically. RESULTS: A total of 2,946 shoulders from 1,568 patients were analyzed with X-rays. Thirteen cases out of 1,568 patients had an os acromiale; and there were five and eight cases of pre-acromiale and meso-acromiale, respectively. Thus, the prevalence of os acromiale in this study population was found to be 0.7 (7 cases per 1,000 patients). Bilaterality was found in two cases. Os acromiale was not more frequent according to gender (five males versus eight females, p = 0.525) and hand dominance was not associated with frequency of os acromiale (seven dominant arms versus six non-dominant arms, p = 0.631). A sub-analysis of shoulders with available MRIs (1,074 shoulders) revealed that there were two rotator cuff tears (40%) out of five cases of os acromiale, whereas 607 rotator cuff tears were observed (57%) among 1069 cases without os acromiale. This difference was not statistically significant (p = 0.656). CONCLUSIONS: The identified prevalence of os acromiale in Korean patients who visited shoulder clinics is 0.7%, which is much lower as compared with the prevalence of general population from other ethnic groups. No correlation was observed between rotator cuff tears and os acromiale in this study population.
Acromion/*pathology/*radiography ; Adult ; Aged ; Ambulatory Care Facilities ; Female ; Humans ; Joint Diseases/*epidemiology/pathology/radiography ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Prevalence ; Republic of Korea/epidemiology ; Retrospective Studies ; Rotator Cuff/*pathology/*radiography ; Shoulder Impingement Syndrome

OBJECTIVE: To compare the accuracy between a three-dimensional (3D) indirect isotropic T1-weighted fast spin-echo (FSE) magnetic resonance (MR) arthrography and a conventional two-dimensional (2D) T1-weighted sequences of indirect MR arthrography for diagnosing rotator cuff tears. MATERIALS AND METHODS: The study was approved by our Institutional Review Board. In total, 205 patients who had undergone indirect shoulder MR arthrography followed by arthroscopic surgery for 206 shoulders were included in this study. Both conventional 2D T1-weighted FSE sequences and 3D isotropic T1-weighted FSE sequence were performed in all patients. Two radiologists evaluated the images for the presence of full- or partial-thickness tears in the supraspinatus-infraspinatus (SSP-ISP) tendons and tears in the subscapularis (SSC) tendons. Using the arthroscopic findings as the reference standard, the diagnostic performances of both methods were analyzed by the area under the receiver operating characteristic curve (AUC). RESULTS: Arthroscopy confirmed 165 SSP-ISP tendon tears and 103 SSC tendon tears. For diagnosing SSP-ISP tendon tears, the AUC values were 0.964 and 0.989 for the 2D sequences and 3D T1-weighted FSE sequence, respectively, in reader I and 0.947 and 0.963, respectively, in reader II. The AUC values for diagnosing SSC tendon tears were 0.921 and 0.925, respectively, for reader I and 0.856 and 0.860, respectively, for reader II. There was no significant difference between the AUC values of the 2D and 3D sequences in either reader for either type of tear. CONCLUSION: 3D indirect isotropic MR arthrography with FSE sequence and the conventional 2D arthrography are not significantly different in terms of accuracy for diagnosing rotator cuff tears.
Adolescent ; Adult ; Aged ; Area Under Curve ; Female ; Humans ; Imaging, Three-Dimensional ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; ROC Curve ; Retrospective Studies ; Rotator Cuff/injuries/pathology/*radiography ; Sensitivity and Specificity ; Shoulder Joint/injuries/pathology/*radiography ; Tendons/pathology/radiography ; Young Adult

OBJECTIVE: To compare the image quality of shoulder CT arthrography performed using 120 kVp and 140 kVp protocols. MATERIALS AND METHODS: Fifty-four CT examinations were prospectively included. CT scans were performed on each patient at 120 kVp and 140 kVp; other scanning parameters were kept constant. Image qualities were qualitatively and quantitatively compared with respect to noise, contrast, and diagnostic acceptability. Diagnostic acceptabilities were graded using a one to five scale as follows: 1, suboptimal; 2, below average; 3, acceptable; 4, above average; and 5, superior. Radiation doses were also compared. RESULTS: Contrast was better at 120 kVp, but noise was greater. No significant differences were observed between the 120 kVp and 140 kVp protocols in terms of diagnostic acceptability, signal-to-noise ratio, or contrast-to-noise ratio. Lowering tube voltage from 140 kVp to 120 kVp reduced the radiation dose by 33%. CONCLUSION: The use of 120 kVp during shoulder CT arthrography reduces radiation dose versus 140 kVp without significant loss of image quality.
Adult ; Aged ; Contrast Media/diagnostic use ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies ; Radiation Dosage ; Radiographic Image Interpretation, Computer-Assisted ; Shoulder/*radiography/surgery ; Shoulder Dislocation/pathology/radiography ; Signal-To-Noise Ratio ; *Tomography, X-Ray Computed

OBJECTIVE: To optimize the dose of contrast agent and the level of energy for dual-energy computed tomography (DECT) arthrography of the shoulder joint and to evaluate the benefits of the optimized imaging protocol. MATERIALS AND METHODS: Dual-energy scans with monochromatic spectral imaging mode and conventional single energy scans were performed on a shoulder phantom with 10 concentrations from 0 to 210 mg/mL of iodinated contrast medium at intervals of 15 or 30 mg/mL. Image noise, tissue contrast, and beam hardening artifacts were assessed to determine the optimum dose of contrast agent and the level of monochromatic energy for DECT shoulder arthrography in terms of the lowest image noise and the least beam hardening artifacts while good tissue contrast was maintained. Material decomposition (MD) imaging for bone-iodine differentiation was qualitatively assessed. The optimized protocol was applied and evaluated in 23 patients. RESULTS: The optimal contrast dose and energy level were determined by the phantom study at 60 mg/mL and 72 keV, respectively. This optimized protocol for human study reduced the image noise and the beam-hardening artifacts by 35.9% and 44.5%, respectively. Bone-iodine differentiation by MD imaging was not affected by the iodine concentration or level of energy. CONCLUSION: Dual-energy scan with monochromatic spectral imaging mode results in reduced image noise and beam hardening artifacts.
Analysis of Variance ; Artifacts ; Contrast Media/*diagnostic use ; Female ; Humans ; Male ; Middle Aged ; Phantoms, Imaging ; Shoulder Joint/pathology/*radiography ; Signal-To-Noise Ratio ; *Tomography, X-Ray Computed

Shoulder dislocation is frequently encountered by orthopedists, and closed manipulation is often sufficient to treat the injury in an acute setting. Although most dislocations are diagnosed and managed promptly, there are rare cases that are missed or neglected, leading to a chronically dislocated state of the joint. They are usually irreducible and cause considerable pain and functional disability in most affected patients, prompting the need to find a surgical method to reverse the worsening conditions caused by the dislocated joint. However, there are cases of even greater rarity in which chronic shoulder dislocations are asymptomatic with minimal functional or structural degeneration in the joint. These patients are usually left untreated, and most show good tolerance to their condition without developing disabling symptoms or significant functional loss over time. We report on one such patient who had a chronic shoulder dislocation for more than 2 years without receiving treatment.
Accidental Falls ; Aged ; Humans ; Magnetic Resonance Imaging ; Male ; Radiography ; Range of Motion, Articular ; Recurrence ; *Rotator Cuff Injuries/diagnosis/diagnostic imaging/physiopathology ; *Shoulder/diagnostic imaging/pathology/physiopathology ; *Shoulder Dislocation/diagnosis/diagnostic imaging/physiopathology

PURPOSE: There has been few published on arthroscopy of metacarpophalangeal joint (MCPJ) despite increasingly being used worldwide. The purpose of this study was to investigate the effectiveness of arthroscopy for pathologies around MCPJ of the thumb. METHODS: Between September 2007 and June 2015, 56 patients (56 thumb) who underwent arthroscopy of the MCPJ were retrospectively studied. Preoperative diagnoses, which were made through physical examination, plain radiograph, stress radiography, ultrasound, and magnetic resonance images (MRI), were compared with arthroscopic findings. Therapeutic arthroscopic surgeries were performed according to the needs of each patient. Functional outcomes were assessed with physical examination as well as disabilities of the arm, shoulder and hand (DASH) score and Michigan Hand outcomes Questionnaire (MHQ) score at an average 7.3 months follow-up. RESULTS: Six patients who suspected with collateral ligament injuries in MRI confirmed different diagnoses under arthroscopy. At final follow-up, the mean range of flexion contracture of the MCPJ was 5°, and the mean range of further flexion was 52.7°. Grip and pinch strength averaged 87.2% and 79.3% of contralateral side. Mean DASH and MHQ score were improved from 48.1 and 44.6, preoperatively to 14.9 and 26.3, postoperatively (p<0.001, p=0.012, respectively). All patients were satisfied with their outcomes at final follow-up, except 4 patients who noted joint stiffness or chronic pain around the thumb. CONCLUSION: Our results revealed that arthroscopy is helpful for both diagnostic and therapeutic purposes of acute and chronic painful MCPJ of the thumb. However, further studies are needed to expand the applications of arthroscopy of MCPJ of the thumb.
Arm ; Arthroscopy* ; Chronic Pain* ; Collateral Ligaments ; Contracture ; Diagnosis ; Follow-Up Studies ; Hand ; Hand Strength ; Humans ; Joints ; Magnetic Resonance Imaging ; Metacarpophalangeal Joint* ; Michigan ; Pathology ; Physical Examination ; Pinch Strength ; Radiography ; Retrospective Studies ; Shoulder ; Thumb* ; Ultrasonography

OBJECTIVETo study the clinicopathologic features and differential diagnosis of myxoid dermafibrosarcoma protuberans (DFSP).

METHODSThe clinical and pathologic features of 16 cases of myxoid DFSP were reviewed.

RESULTSThere were altogether 15 males and 1 female. The age of the patients ranged from 11 to 73 years (mean = 47 years and median = 48 years). The commonest site of involvement was trunk (number = 11), followed by shoulder (number = 2), head and neck (number = 2), and extremity (number = 1). Similar to conventional DFSP, most patients presented with a slowly enlarging subcutaneous nodule which showed a rapid recent growth in some cases. Amongst the 16 cases studied, 12 occurred de novo and 4 represented local recurrence. The tumors ranged from 2 to 10 cm in greatest dimension (mean = 5 cm and median = 4 cm). Histologically, they were poorly circumscribed and located in the dermis, with focal infiltration into the underlying subcutaneous tissue. Seven cases were purely myxoid and composed of spindly and stellate cells with delicate arborizing vascular meshwork. The remaining 9 cases were predominantly myxoid (> 50%), with 5 cases containing cellular areas resembling conventional DFSP and 4 cases showing fibrosarcomatous transformation. In addition, foci of giant cell fibroblastoma-like areas were noted in 1 case. Immunohistochemical study showed that the tumors cells were positive for CD34. The staining was weak in the myxoid areas, as compared with conventional DFSP. Of the 4 recurrent cases, one patient developed lung metastases.

CONCLUSIONSMyxoid DFSP represents a rare variant of DFSP and may pose important diagnostic pitfalls. It is especially so if the tumor purely consists of myxoid element. Familiarity with the histologic features helps to avoid misdiagnosis.

Abdominal Wall ; Adolescent ; Adult ; Aged ; Antigens, CD34 ; metabolism ; Child ; Dermatofibrosarcoma ; diagnostic imaging ; immunology ; pathology ; surgery ; Diagnosis, Differential ; Female ; Head and Neck Neoplasms ; diagnostic imaging ; immunology ; pathology ; surgery ; Humans ; Lung Neoplasms ; secondary ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; Radiography ; Shoulder ; Skin Neoplasms ; diagnostic imaging ; immunology ; pathology ; surgery ; Young Adult