Differences Between Subtalar Instability and Lateral Ankle Instability Focusing on Subtalar Ligaments Based on Three Dimensional Isotropic Magnetic Resonance Imaging.

OBJECTIVE: The purpose of this study was to assess the differences between subtalar instability (STI) and lateral ankle instability (LAI) focusing on subtalar ligaments using 3-dimensional (3D) isotropic magnetic resonance imaging (MRI). METHODS: Preoperative MRIs of 10 patients with STI who failed nonoperative treatment and consequently underwent arthroscopic subtalar reconstruction were compared with preoperative MRIs of 23 patients with LAI who underwent ligament repair or reconstruction. Dimensions of anterior capsular ligament (ACL), interosseous talocalcaneal ligament (ITCL), calcaneofibular ligament (CFL), and anterior talofibular ligament (ATFL) were measured. Tears of ACL, ITCL, CFL, ATFL, cervical ligament, and inferior extensor retinaculum were analyzed. RESULTS: Patients with subtalar instability had significantly lower ACL thickness and width than patients with LAI (thickness: 1.48 vs 2.12 mm, P = 0.045; width: 7.30 vs 8.64 mm, P = 0.029). An ACL thickness of 1.8 mm or less had sensitivity and specificity both at 75.0%, and an ACL width of 8 mm or less had sensitivity of 75.0% and specificity of 85.0% for discriminating STI from LAI. Absence or complete tear of ACL was more frequent in patients with STI than in patients with LAI (60.0% vs 13.0%, P = 0.010). The ATFL thickness was significantly greater in patients with LAI (P = 0.001). Complete tear of ATFL was more common in patients with LAI (P = 0.008). Complete tear of CFL was common in both the STI and LAI groups without significant difference (20.0% vs 21.7%). There was no significant difference in thickness and width of ITCL and in CFL thickness. Complete tear of ITCL, cervical ligament, and inferior extensor retinaculum were rare without significant difference. CONCLUSION: In patients with STI, the ACL is thin and narrow and more commonly absent or torn compared with patients with LAI. Complete tear of ATFL was more common in patients with LAI. Complete tear of CFL was commonly encountered in both the STI and LAI groups.

Evaluation of Anterolateral Ligament Injuries and Concomitant Lesions on Magnetic Resonance Imaging After Acute Anterior Cruciate Ligament Rupture.

PURPOSE: To evaluate the prevalence and characteristics of anterolateral ligament (ALL) injuries with a ruptured acute anterior cruciate ligament (ACL) and to analyze the presence of concomitant bone contusions and meniscal lesions. METHODS: From March 2015 to March 2017, we retrospectively analyzed 378 patients who underwent primary ACL reconstructions. Using magnetic resonance imaging, we evaluated the presence of ALL injury and concomitant lesions within 3 weeks of the injury. Meniscal tears were also identified on representative arthroscopic images. RESULTS: Following the inclusion criteria, we included a total of 275 patients in this study. The mean duration from ACL rupture to magnetic resonance imaging examination was 5.0 ± 6.0 days. We visualized ALL in 98.2% of patients, of whom 64% had ALL injuries (10.9%, 4.7%, and 48.4% were complete ruptures, Segond fracture, and partial ruptures, respectively). We found that ALL injuries were most commonly found in the femoral location. The intra- and interobserver agreement on the severity of ALL injury (κ = 0.83 and 0.81, respectively) and the location of ALL injury (κ = 0.85 and 0.84, respectively) were excellent. The association between ALL injury and lateral meniscal lesions was significant (P = .03). In particular, the proportion of the lateral meniscal posterior horn radial tears was significantly larger in nonintact ALL than in intact ALL (P = .042). The correlation between the severity of ALL injury and the degree of bone contusion at lateral compartments was significant but weak (P < .001). CONCLUSIONS: We found that more than half of acute ACL ruptures have ALL injuries. The presence of ALL injury was significantly associated with the presence of lateral meniscal lesions, especially lateral meniscal posterior horn radial tears, or lateral bone contusions. Interestingly, the severity of ALL injury significantly correlated with the degree of lateral bone contusions. LEVEL OF EVIDENCE: Level III, diagnostic cross-sectional study.

CT arthrography visualizes tissue growth of osteochondral defects of the talus after microfracture.

PURPOSE: Little is known about the arthroscopic or radiographic outcomes after arthroscopic microfracture of osteochondral lesions of the talus (OLTs). The purpose of this study was to investigate tissue growth after arthroscopic microfracture of OLTs using computed tomography arthrography (CTA) and to identify the relationship between CTA findings and clinical outcomes. We hypothesized that the morphology of the repaired tissue would be similar to that of normal anatomy and correlate with the clinical outcomes. METHODS: Forty-two ankles treated using arthroscopic microfracture of OLTs between 2009 and 2014 were monitored. CTA was performed post-operatively at 6 months and at 1 and 2 years after surgery. The post-operative thickness of the repaired tissue associated with OLT (grade) and the volume of the subchondral cystic lesions were evaluated using CTA. Clinical outcomes, including the pain visual analog scale (VAS) and American Orthopaedic Foot and Ankle Society (AOFAS) ankle functional scores, were evaluated and correlated with CTA. RESULTS: The proportion of fully grown tissue (grade 3) increased over time; specifically, the rates were 12/40 (33.3%) at 6 months, 11/18 (61.1%) at 1 year, and 8/10 (80%) at 2 years after surgery (p = 0.005). The VAS pain (p < 0.001) and AOFAS scores (p < 0.001) were also improved at the final follow-up; however, they were not associated with repaired tissue thickness as shown by CTA (n.s.). CONCLUSIONS: After microfracture of OLTs, tissue growth in the osteochondral defects was well visualized using CT arthrography and was observed in most cases. However, the CTA findings were not related to the clinical outcomes. LEVEL OF EVIDENCE: IV.

Automated detection and classification of the proximal humerus fracture by using deep learning algorithm.

Background and purpose - We aimed to evaluate the ability of artificial intelligence (a deep learning algorithm) to detect and classify proximal humerus fractures using plain anteroposterior shoulder radiographs. Patients and methods - 1,891 images (1 image per person) of normal shoulders (n = 515) and 4 proximal humerus fracture types (greater tuberosity, 346; surgical neck, 514; 3-part, 269; 4-part, 247) classified by 3 specialists were evaluated. We trained a deep convolutional neural network (CNN) after augmentation of a training dataset. The ability of the CNN, as measured by top-1 accuracy, area under receiver operating characteristics curve (AUC), sensitivity/specificity, and Youden index, in comparison with humans (28 general physicians, 11 general orthopedists, and 19 orthopedists specialized in the shoulder) to detect and classify proximal humerus fractures was evaluated. Results - The CNN showed a high performance of 96% top-1 accuracy, 1.00 AUC, 0.99/0.97 sensitivity/specificity, and 0.97 Youden index for distinguishing normal shoulders from proximal humerus fractures. In addition, the CNN showed promising results with 65-86% top-1 accuracy, 0.90-0.98 AUC, 0.88/0.83-0.97/0.94 sensitivity/specificity, and 0.71-0.90 Youden index for classifying fracture type. When compared with the human groups, the CNN showed superior performance to that of general physicians and orthopedists, similar performance to orthopedists specialized in the shoulder, and the superior performance of the CNN was more marked in complex 3- and 4-part fractures. Interpretation - The use of artificial intelligence can accurately detect and classify proximal humerus fractures on plain shoulder AP radiographs. Further studies are necessary to determine the feasibility of applying artificial intelligence in the clinic and whether its use could improve care and outcomes compared with current orthopedic assessments.

Subtalar instability: imaging features of subtalar ligaments on 3D isotropic ankle MRI.

BACKGROUND: MRI analysis of subtalar ligaments in the tarsal sinus has not been well performed. We retrospectively investigated the appearance of subtalar ligaments using 3D isotropic MRI and compared imaging findings of subtalar ligaments between patients with subtalar instability (STI) and controls. METHODS: Preoperative MRIs of 23 STI patients treated with arthroscopic subtalar reconstruction were compared to MRIs of 23 age- and sex-matched control subjects without STI. Thickness and width of anterior capsular ligament (ACL) and interosseous talocalcaneal ligament (ITCL) as well as thickness of calcaneofibular ligament (CFL) and anterior talofibular ligament (ATFL) were measured. Abnormalities in ACL, ITCL, CFL, ATFL, cervical ligament, and inferior extensor retinaculum were analyzed. RESULTS: STI patients had significantly smaller ACL thickness and ACL width than controls (ACL thickness: 1.73 mm vs. 2.22 mm, p = 0.007; ACL width: 7.21 mm vs. 8.80 mm, p = 0.004). ACL thickness of ≤2.1 mm had a sensitivity of 66.7% and a specificity of 66.7% for diagnosis of STI. ACL width of ≤7.9 mm had a sensitivity of 80.0% and a specificity of 76.2% for the diagnosis of STI. However, thickness and width of ITCL, thickness of CFL, or thickness of ATFL was not significantly different between the two groups. Absence or complete tear of ACL was significantly more frequent in STI patients than that in controls (34.8% vs. 8.7%, p = 0.035). Complete tear of CFL and ATFL was more common in STI patients than that in controls, although the difference between the two groups was not statistically significant. Abnormalities of ITCL, cervical ligament, or inferior extensor retinaculum were not significantly different between the two groups. CONCLUSIONS: MRI features of thin or narrow ACLs may suggest STI. Absence or complete tear of ACL was significantly more common in STI patients than that in controls.

Stress ultrasound in baseball players with ulnar collateral ligament injuries: additional value for predicting rehabilitation outcome.

BACKGROUND: The purpose of this study was to evaluate the additional value of stress ultrasound (US) for predicting rehabilitation outcome in baseball players with ulnar collateral ligament (UCL) injury. METHODS: Stress US and magnetic resonance imaging (MRI) in 41 baseball players with UCL injury who received rehabilitation treatment for more than 6 weeks were retrospectively compared between the rehabilitation group (n = 23) and surgery group (n = 18). The MRI grade of UCL injury was assessed as intact continuity, low-grade partial tear, high-grade partial tear, and complete tear. To estimate sonographic joint laxity, we assessed 3 sonographic criteria as present or absent: ligamentous waviness, joint gapping, and intra-articular ring-down artifact. In addition, the presence of concomitant tenderness was checked during stress US. The diagnostic validity of MRI with and without stress US was analyzed as a predictor for the rehabilitation outcome. RESULTS: The MRI grade was higher in the surgery group than in the rehabilitation group (P < .001). Sonographic joint laxity showing the ring-down artifact and concomitant tenderness with stress were significantly more frequent in the surgery group (P = .024 and P = .006, respectively). Sensitivity, specificity, and accuracy were 61.1%, 86.9%, and 75.6%, respectively, for MRI alone and 83.3%, 56.5%, and 68.2%, respectively, for the combination of MRI with joint laxity showing the ring-down artifact. For MRI in combination with joint laxity and concomitant tenderness, these values were 72.2%, 82.6%, and 78.0%, respectively. CONCLUSION: The addition of stress US showing the ring-down artifact and concomitant tenderness was helpful for predicting the rehabilitation outcome of UCL injuries.

Superior Labral Cleft after Superior Labral Anterior-to-Posterior Tear Repair: CT Arthrographic Features and Correlation with Clinical Outcome.

PURPOSE: To evaluate the presence of a superior labral cleft at postoperative computed tomographic (CT) arthrography after superior labral anterior-to-posterior lesion (SLAP) repair and to correlate CT arthrographic appearance with clinical outcomes. MATERIALS AND METHODS: The institutional review board approved this retrospective study, and the requirement to obtain informed consent was waived. Fifty-six patients who underwent CT arthrography after arthroscopic SLAP repair were included. Two musculoskeletal radiologists retrospectively reviewed CT arthrographic images for the presence, size, location, direction, and shape of a superior labral cleft, which was defined as a detectable contrast material-filled focal discontinuity of the labrum within anchor fixation sites of the glenoid. In addition, the glenoid osteolysis ratio was calculated on the basis of the CT arthrographic images. Clinical outcome was evaluated with use of the American Shoulder and Elbow Surgeons (ASES) scoring system. Continuous variables, such as patient age, interval between imaging and surgery, ASES score, and osteolysis ratio, were compared by using the Mann-Whitney U test. RESULTS: A superior labral cleft was observed in 27 of the 56 patients (48%). The mean width and depth of the superior labral clefts was 2.1 mm ± 1.1 and 2.8 mm ± 0.8, respectively. The superior labral clefts extended posterior to the biceps anchor in 16 of the 27 patients (59%), were curved medially in 24 (89%), and had a smooth margin in 22 (81%). No significant association was observed between the presence of a superior labral cleft and the ASES score (P = .805) or patient age (P = .290). Superior labral clefts were observed more commonly in cases with a long interval since surgery (P = .007) and a high osteolysis ratio (P = .011). CONCLUSION: Superior labral clefts are frequently observed on CT arthrographic images after arthroscopic SLAP repair and do not correlate with clinical outcome.

Valgus extension overload syndrome in adolescent baseball players: clinical characteristics and surgical outcomes.

BACKGROUND: Little is known about the clinical characteristics and surgical outcomes of valgus extension overload syndrome (VEOS) in adolescent athletes. We evaluated posteromedial compartment pathology, including combined lesions, and reported the surgical outcomes in adolescent baseball players. METHODS: We retrospectively reviewed the medical records of 13 male adolescent baseball players (mean age, 15.4 years) who underwent arthroscopic olecranon tip resection (n = 9) or staged operations (arthroscopic olecranon tip resection, followed by medial collateral ligament reconstruction 2 weeks later; n = 4). The shape of the tip fragment was used to classify the olecranon into 2 types: type 1, dot-like fragment (n = 3); type 2, triangular-shape fragment (n = 10). Four outcome measures were analyzed: range of motion, visual analog scale (VAS) pain score, rate of return to play, and Conway scale score. RESULTS: At a mean follow-up of 3.3 years (range, 2-6 years), the mean VAS pain score decreased from 4.1 preoperatively to 1.1 postoperatively (P < .05). Preoperative mean extension and supination were 4.2° and 70.0°, which improved to 1° (P < .05) and 76.2° (P < .05), respectively. The overall rate of return to play was 85% (11 of 13). On the Conway scale, 8 of 13 patients (62%) were classified as excellent. Patients who underwent isolated arthroscopic surgery reported less pain postoperatively and achieved a higher grade on the Conway scale than patients who underwent staged operations. CONCLUSIONS: Arthroscopic resection of olecranon tip yielded favorable outcomes at a minimum of 2 years of follow-up. Patients with concomitant ulnar collateral ligament insufficiency had less optimal outcomes than those with isolated posteromedial impingement.

Revisit to scapular dyskinesis: three-dimensional wing computed tomography in prone position.

BACKGROUND: Three-dimensional (3D) wing computed tomography (CT) showed a high inter-rater reliability in assessing scapular dyskinesis. METHODS: The 330 scapular movements of 165 patients were classified into 4 types by 7 blinded observers. Then, 3D wing CT was performed with patients prone, and 4 blinded observers measured 5 angles, consisting of upward rotation (UR) superior translation (ST), anterior tilting (AT), protraction (PRO), and internal rotation (IR). The inter-rater reliability (IRR) of 2 methods was calculated, and cutoff values were determined for the 5 angles on the 3D wing CT images. RESULTS: The IRR was 0.783 for the observational method of scapular dyskinesis and 0.981 for 3D wing CT in the prone position. UR and ST angles were significantly larger in type 3 more than in the other types (P < .001, P < .001), and the AT angle showed a similar pattern in type 1 (P < .001). The PRO angle was significantly larger in types 1, 2, and 3 more than in type 4 (P < .001, P < .001, P = .013), and the IR angle was significantly larger in type 2 more than in the other types (P < .001). The cutoff values of the 5 angles were UR, 117°; ST, 90°; AT, 8°; PRO, 99°; and IR, 51°. The UR angle showed a significant correlation with glenohumeral internal rotation deficit (odds ratio, 0.436; P = .029) and the IR angle with MDI (odds ratio, 8.947; P = .048). CONCLUSION: The patients with a high UR angle showed a low rate of glenohumeral internal rotation deficit and those with a high IR angle had a high rate of the MDI in affected shoulder by the determinant of the cutoff value of the 5 angles. LEVEL OF EVIDENCE: Level III, development of diagnostic criteria with nonconsecutive patients, diagnostic study.

Multidirectional instability of the shoulder: rotator interval dimension and capsular laxity evaluation using MR arthrography.

OBJECTIVES: To compare the rotator interval and capsular dimension as measured on MR arthrography between patients with clinically diagnosed multidirectional instability (MDI) and control subjects with no instability. MATERIALS AND METHODS: We retrospectively reviewed a consecutive series of 658 shoulders that had undergone MR arthrography between 2006 and 2010. Of these, 97 shoulders were included in the present study. These shoulders were divided into two groups according to the clinically established diagnoses. The MDI group comprised 47 shoulders with atraumatic multidirectional shoulder instability, and the control group comprised 50 shoulders with no instability. Two independent observers measured the width and depth of the rotator interval, and the capsular dimensions at the anterior, anteroinferior, inferior, posteroinferior, and posterior regions in the two groups using MR arthrography. RESULTS: The rotator interval width and depth were significantly greater in the MDI group (width, observer 1, 17.7 mm, observer 2, 17.9 mm; depth, observer 1, 8.9 mm, observer 2, 8.8 mm) than in the control group (width, observer 1, 14.3 mm, observer 2, 14.5 mm; depth, observer 1, 5.9 mm, observer 2, 6.2 mm) (p < .001). The capsular dimensions at the inferior and posteroinferior regions were significantly larger in the MDI group (inferior, observer 1, 27.9 mm, observer 2, 27.8 mm; posteroinferior, observer 1, 27.0 mm, observer 2, 27.1 mm) than in the control group (inferior, observer 1, 25.7 mm, observer 2, 25.3 mm; posteroinferior, observer 1, 23.3 mm, observer 2, 23.6 mm) (p < .05). A width greater than 15.2 mm or a depth greater than 6.4 mm of the rotator interval, suggesting MDI, had sensitivities of 81 and 92 % for observer 1, and 79 and 94 % for observer 2, and specificities of 66 and 72 % for observer 1, and 62 and 66 % for observer 2, respectively. CONCLUSIONS: Measurements of the rotator interval and the size of the distended inferior and posteroinferior joint capsule on MR arthrography are greater in shoulders with clinical MDI than in stable shoulders.

A machine learning-integrated stepwise method to discover novel anti-obesity phytochemicals that antagonize the glucocorticoid receptor.

As a type of stress hormone, glucocorticoids (GCs) affect numerous physiological pathways by binding to the glucocorticoid receptor (GR) and regulating the transcription of various genes. However, when GCs are dysregulated, the resulting hypercortisolism may contribute to various metabolic disorders, including obesity. Thus, attempts have been made to discover potent GR antagonists that can reverse excess-GC-related metabolic diseases. Phytochemicals are a collection of valuable bioactive compounds that are known for their wide variety of chemotypes. Recently, various computational methods have been developed to obtain active phytochemicals that can modulate desired target proteins. In this study, we developed a workflow comprising two consecutive quantitative structure-activity relationship-based machine learning models to discover novel GR-antagonizing phytochemicals. These two models collectively identified 65 phytochemicals that bind to and antagonize GR. Of these, nine commercially available phytochemicals were validated for GR-antagonist and anti-obesity activities. In particular, we confirmed that demethylzeylasteral, a phytochemical of the Tripterygium wilfordii Radix, exhibits potent anti-obesity activity in vitro through GR antagonism.

Chronologic change in the growth plate after radiofrequency-induced thermal injury: MRI-histologic correlation.

OBJECTIVE: The purposes of this study were to assess chronologic changes in normal growth plate after radiofrequency-induced thermal injury and to evaluate the feasibility of MRI for revealing alteration of the growth plate. MATERIALS AND METHODS: Radiofrequency ablation was performed on the right proximal tibia of 13 8-week-old New Zealand White rabbits. An 18-gauge cooled-tip electrode with a 5-mm active tip was placed distal to the physis under fluoroscopic guidance. MRI, including T1- and T2-weighted images, gradient-recalled echo images, and contrast-enhanced T1-weighted images, was performed 2, 4, and 12 weeks after ablation. Rabbits were sacrificed 2 (n = 4), 4 (n = 4), and 12 weeks (n = 5) after ablation. The sequential changes in the ablated zone, the injured physis, and the nonablated portion of the physis were correlated between MRI features and histologic results. RESULTS: Diameter of the nonenhancing lesion on MR images strongly correlated with the size of the region of coagulation necrosis at gross examination. The intraclass correlation coefficients were 0.98 and 0.94 for the long and short axes (p < 0.001). On gradient-recalled echo images, physial conspicuity was less in the injured physis than in the nonablated portion and less in the ablated than the control tibia. Physial conspicuity was graded for comparison with physial thickness at microscopic examination. The thickness of the physis was less in the ablated than in the control tibia 4 and 12 weeks after treatment (p < 0.05, paired Student t test). The cartilage column of the injured physis was delaminated 2 weeks after treatment, and a bone bridge through the injured physis was detected at 4 weeks. CONCLUSION: Radiofrequency-induced thermal injury causes early closure of the physis. MRI can depict the extent of radiofrequency-induced thermal injury and alterations in the physis that lead to early closure.

Acute coccydynia related to precoccygeal calcific tendinitis.

Symptomatic deposits of calcium hydroxyapatite have been reported in various sites other than the shoulders or hips. Sudden-onset coccydynia can lead to the discovery of calcific deposition in the precoccygeal region. We present the case of precoccygeal calcific tendinitis in a patient with acute coccydynia.

Effects of epidural TNF-α inhibitor injection: analysis of the pathological changes in a rat model of chronic compression of the dorsal root ganglion.

OBJECTIVES: To evaluate the efficacy of a single direct epidural injection of tumor necrosis factor (TNF)-α inhibitor to reduce the pathological changes in nerve fiber injuries in a rat model of chronic compression of the dorsal root ganglion (CCD). MATERIALS AND METHODS: A surgical procedure for CCD was performed in 17 adult male F-344 rats. The effects of the epidural TNF-α inhibitors on CCD-induced pathological changes were investigated. Three groups of rats (n = 17) were used: (1) CCD + saline (n = 4), (2) CCD + triamcinolone (n = 5), and (3) CCD + TNF-α inhibitors (n = 8). Their dorsal root ganglia and nerve roots were removed on postoperative day 14. The intraneural edema, demyelination, and Wallerian degeneration of all 17 rats were scored pathologically. RESULTS: The pathology scores of the rats in the TNF-α inhibitor treatment group (1.38 ± 0.74) indicated a mild degree of intraneural edema compared to the saline treatment group (2.25 ± 0.50, p = 0.041). In addition, rats in the TNF-α inhibitor treatment group (2.13 ± 0.35) had a mild degree of demyelination compared to the saline treatment group (2.75 ± 0.50, p = 0.038) and the triamcinolone treatment group (2.80 ± 0.45, p = 0.019). The differences in the pathology scores for Wallerian degeneration were not statistically significant in all three study groups (p = 0.658). CONCLUSION: The epidural injection of a TNF-α inhibitor was more effective than a placebo and comparable to triamcinolone in reducing pathological nerve injury progression.

Is arthroscopic coracoplasty necessary in subcoracoid impingement syndrome?

PURPOSE: The purpose of this study was to analyze the outcomes of arthroscopic coracoplasty in the treatment of subcoracoid impingement syndrome. METHODS: We compared 23 shoulders that underwent arthroscopic coracoplasty for the treatment of subcoracoid impingement syndrome with 28 shoulders that did not undergo arthroscopic coracoplasty for the treatment of subcoracoid impingement syndrome, which comprised the control group. All the shoulders had subcoracoid and subacromial impingement syndrome with or without rotator cuff tear. Subcoracoid impingement was defined as a coracohumeral distance of less than 6 mm on the preoperative magnetic resonance image with anterior shoulder pain or tenderness. The 2 groups were further divided into several subgroups according to the size of concomitant rotator cuff tear, and a comparative analysis of functional outcomes after surgery among the subgroups was performed. RESULTS: In the 2 groups, the overall functional outcomes improved after surgery. The study group showed a significant increase in internal rotation compared with that in the control group (P = .001) at the last follow-up. The large to massive rotator cuff tear subgroup of the study group showed a significant increase in internal rotation (P = .017). On the other hand, no significant difference was seen in the subgroups with small to medium rotator cuff tears including isolated subscapularis tears. The no rotator cuff tear subgroup of the study group showed a significant increase in internal rotation (P = .046). CONCLUSIONS: Arthroscopic coracoplasty for subcoracoid impingement syndrome can provide a satisfactory outcome. In particular, a significant increase in internal rotation of the treated group was achieved after surgery in comparison with the untreated group, especially in the large to massive rotator cuff tear subgroup and in the no rotator cuff tear subgroup. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Cyst-like solid tumors of the musculoskeletal system: an analysis of ultrasound findings.

OBJECTIVE: When evaluating superficial soft tissue masses with ultrasonography, it is not always clear whether the mass is cystic or solid. We reviewed sonograms of soft tissue masses, which were interpreted as cystic but confirmed as solid tumors. MATERIALS AND METHODS: We scanned a database of patients with superficial soft tissue masses from two different institutions. Four hundred and thirty lesions were evaluated with ultrasonography and then confirmed surgically. Twenty-three masses were identified, of which initial interpretation on gray scale included cystic tumor which pathology revealed to be solid tumors. All images were evaluated by two musculoskeletal radiologists, regarding internal echogenicity of lesions, presence of posterior enhancement, margins, size, and internal vascularity. RESULTS: Of 23 masses, there were 5 giant cell tumors of the tendon sheath, 4 schwannomas, 3 vascular leiomyomas, 2 benign fibrous histiocytomas, 2 dermatofibrosarcoma protuberans, 2 granular cell tumors, 1 dermatofibroma, 1 fibroma of the tendon sheath, 1 fibromatosis, 1 eccrine spiradenoma, and 1 granulation tissue. Masses were hypoechoic in 16 and anechoic in 7 cases. Posterior enhancement was present in 9, and 10 masses showed no internal vascularity on color Doppler imaging. Margins were smooth in 13, smooth with mild lobulation in 7, and lobulated in 3 cases. Mean size was 2.3 cm. CONCLUSION: On ultrasonography, solid soft tissue tumors may be confused with cystic masses. Such cases are not common, and fibrous tumors are the most frequent. Care should be given to these solid tumors that have a cystic appearance and even lack internal vascularity on color Doppler imaging to enhance diagnosis of cystic and solid masses.

Spreading epidural hematoma and deep subcutaneous edema: indirect MRI signs of posterior ligamentous complex injury in thoracolumbar burst fractures.

OBJECTIVES: The purpose of this study was to evaluate the diagnostic value of a spreading epidural hematoma (SEH) and deep subcutaneous edema (DSE) as indirect signs of posterior ligamentous complex (PLC) injuries on MR imaging of thoracolumbar burst fractures. MATERIALS AND METHODS: We retrospectively reviewed spinal MR images of 43 patients with thoracolumbar burst fractures: 17 patients with PLC injuries (study group) and 26 without PLC injuries (control group). An SEH was defined as a hemorrhagic infiltration into the anterior or posterior epidural space that spread along more than three vertebrae including the level of the fracture. A DSE was regarded as a fluid-like signal lesion in the deep subcutaneous layer of the back, and its epicenter was at the burst fracture level. The frequency of the SEH/DSE in the two groups was analyzed. In addition, the association between each sign and the degree of vertebral collapse, the severity of central canal compromise, and surgical decisions were analyzed. RESULTS: Magnetic resonance images showed an SEH in 20 out of 43 patients (46%) and a DSE in 17 (40%). The SEH and DSE were more commonly seen in the study group with PLC injuries (SEH, 15 out of 17 patients, 80%; DSE, 16 out of 17 patients, 94%) than in the control group without PLC injuries (SEH, 5 out of 26, 19%; DSE, 1 out of 26, 4%) (P <0.0001). The SEH and DSE were significantly associated with surgical management decisions (17 out of 20 patients with SEH, 85%, vs 8 out of the 23 without SEH, 35%, P =0.002; 15 out of 17 with DSE, 88%, vs 10 out of 26 without DSE, 38%, P =0.002). The SEH and DSE did not correlate with the degree of vertebral collapse or the severity of central canal compromise. CONCLUSION: The SEH and DSE may be useful secondary MR signs of posterior ligamentous complex injury in thoracolumbar burst fractures.

Effect of atelocollagen on the healing status after medial meniscal root repair using the modified Mason-Allen stitch.

INTRODUCTION: Addition of collagen during medial meniscal root repair (MMRR) may improve meniscal root healing minimising fibrous scar tissue formation. The purpose of this study was to verify the effect of atelocollagen on MMRR using the modified Mason-Allen stitch when compared with that of the conventional pullout repair by assessing the clinical and radiological outcomes. HYPOTHESIS: It was hypothesised that atelocollagen would enhance the healing effect on the meniscal root following MMRR. Moreover, we presumed that MMRR with atelocollagen application might reduce meniscal extrusion by promoting healing. MATERIALS AND METHODS: A total of 47 patients who underwent MMRR using the modified Mason-Allen stitch between 2015 and 2016 were included, and they were divided into group A (atelocollagen application; n=25) and group R (MMRR without atelocollagen application; n=22). The postoperative clinical outcomes, radiological outcomes, and meniscal root healing and medial compartment cartilage status on follow-up magnetic resonance imaging (MRI) were compared between the two groups. RESULTS: Mean follow-up duration was 26.4±4.8 months in group A and 27.1±5.2 months in group R (p=0.598). Mean duration from surgery to follow-up MRI was 12.5±1.4 months in group A and 12.7±1.2 months in group R (p=0.604). The subjective knee scores improved significantly in both groups at the last follow-up (all, p<0.001). The Kellgren-Lawrence (K-L) grade progressed in 16% and 22.7% in group A and group R, respectively (p=0.351). Follow-up MRI showed progression of cartilage loss in the medial compartment in 28% and 40.9% in group A and group R, respectively (p=0.355). In terms of meniscal root healing, 18 (72%) and 12 (54.5%) patients had complete healing, and 6 (24%) and 8 (36.4%) patients had partial healing in groups A and R, respectively. The mean value of the intra-meniscal signal intensity (IMSI) of the meniscal root based on MRI in group A was significantly lower than that in group R (p<0.001). The medial meniscal extrusion in groups A and R decreased by 0.2±0.1mm and 0.1±0.3mm following MMRR without significant differences (p=0.056 and p=0.229, respectively). The IMSI presented significant negative correlations with the root healing status and significant positive correlations with K-L grade progression (p<0.05). DISCUSSION: Atelocollagen application during MMRR yielded lower IMSIs, suggesting better healing, than did conventional pullout root repair. However, this technique could not demonstrate beneficial effects on meniscal extrusion. LEVEL OF EVIDENCE: III, retrospective case-control study.

MR imaging assessment of the spine: infection or an imitation?

Magnetic resonance (MR) imaging is a powerful diagnostic tool that can be used to help evaluate spinal infection and to help distinguish between an infection and other clinical conditions. In most cases of spinal infection, MR images show typical findings such as vertebral endplate destruction, bone marrow and disk signal abnormalities, and paravertebral or epidural abscesses. However, it is not always easy to diagnose a spinal infection, particularly when some of the classic MR imaging features are absent or when there are unusual patterns of infectious spondylitis. Furthermore, noninfectious inflammatory diseases and degenerative disease may simulate spinal infection. It is necessary to be familiar with atypical MR imaging findings of spinal infection and features that may mimic spinal infection to avoid misdiagnosis and inappropriate treatment.

Evaluation of the mydriatic effect of intracameral lidocaine hydrochloride injection in eyes of clinically normal dogs.

OBJECTIVE-To evaluate the mydriatic effect of intracameral injection of preservative-free 1% and 2% lidocaine hydrochloride solutions and determine the onset and duration of mydriasis according to the concentration and volume of lidocaine administered in healthy dogs. ANIMALS-5 healthy adult Beagles weighing 7 to 10 kg, with no apparent ocular disease. PROCEDURES-A double-blind randomized 9-session crossover trial was designed. Both eyes were assigned to 9 treatments with a minimum 7-day washout period between treatments: 0.1, 0.2, and 0.3 mL of 2% lidocaine solution; 0.1, 0.2, and 0.3 mL of 1% lidocaine solution; and 0.1, 0.2, and 0.3 mL of balanced salt solution. Dogs were anesthetized, and the allocated treatment was injected intracamerally after aspiration of the same volume of aqueous humor from the anterior chamber of each eye. Two perpendicular pupil diameters were measured. Intraocular pressure, heart rate, respiratory rate, ECG readings, and end-tidal partial pressure of CO(2) were monitored. RESULTS-Intracameral injection of 1% or 2% lidocaine solutions in volumes of 0.1 to 0.3 mL induced a significant degree of mydriasis, and the effect was maintained for 74 to 142 minutes. Lidocaine injection had no significant effect on intraocular pressure, heart rate, respiratory rate, ECG readings, or end-tidal partial pressure of CO(2). CONCLUSIONS AND CLINICAL RELEVANCE-Intracameral lidocaine injection in healthy dogs induced mydriasis, the timing of which was affected by concentration and volume of lidocaine. This technique could serve as an alternative to topically administered mydriatics for intraocular surgery in dogs.