Scapular dyskinesis after treatment of proximal humerus fracture, a 3-dimensional motion analysis and clinical outcomes.

BACKGROUND: The alteration of scapular kinematics can predispose patients to shoulder pathologies and dysfunction. Previous literature has associated various types of shoulder injuries with scapular dyskinesis, but there are limited studies regarding the effect that proximal humeral fractures (PHFs) have on scapular dyskinesis. This study aims to determine the change in scapulohumeral rhythm following treatment of a proximal humerus fracture as well as differences in shoulder motion and functional outcomes among patients who presented with or without scapular dyskinesis. We hypothesized that differences in scapular kinematics would be present following treatment of a proximal humerus fracture, and patients who presented with scapular dyskinesis would subsequently have inferior functional outcome scores. METHODS: Patients treated for a proximal humerus fracture from May 2018 to March 2021 were recruited for this study. The scapulohumeral rhythm and global shoulder motion were determined using a 3-dimensional motion analysis (3DMA) and the scapular dyskinesis test. Functional outcomes were then compared among patients with or without scapular dyskinesis, including the SICK (scapular malposition, inferomedial border prominence, coracoid pain and malposition, and dyskinesis of scapular movement) Scapula Rating Scale, the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), the visual analog scale (VAS) for pain, and the EuroQol-5 Dimension 5-Level questionnaire (EQ-5D-5L). RESULTS: Twenty patients were included in this study with a mean age of 62.9 ± 11.8 years and follow-up time of 1.8 ± 0.2 years. Surgical fixation was performed in 9 of the patients (45%). Scapular dyskinesis was present in 50% of patients (n = 10). There was a significant increase in scapular protraction on the affected side of patients with scapular dyskinesis during abduction of the shoulder (P = .037). Additionally, patients with scapular dyskinesis demonstrated worse SICK scapula scores (2.4 ± 0.5 vs. 1.0 ± 0.4, P = .024) compared to those without scapular dyskinesis. The other functional outcome scores (ASES, VAS pain scores, and EQ-5D-5L) showed no significant differences among the 2 groups (P = .848, .713, and .268, respectively). CONCLUSIONS: Scapular dyskinesis affects a significant number of patients following treatment of their PHFs. Patients presenting with scapular dyskinesis exhibit inferior SICK scapula scores and have more scapular protraction during shoulder abduction compared to patients without scapular dyskinesis.

Tumor-to-bone distance and radiomic features on MRI distinguish intramuscular lipomas from well-differentiated liposarcomas.

BACKGROUND: To develop a machine learning model based on tumor-to-bone distance and radiomic features derived from preoperative MRI images to distinguish intramuscular (IM) lipomas and atypical lipomatous tumors/well-differentiated liposarcomas (ALTs/WDLSs) and compared with radiologists. METHODS: The study included patients with IM lipomas and ALTs/WDLSs diagnosed between 2010 and 2022, and with MRI scans (sequence/field strength: T1-weighted (T1W) imaging at 1.5 or 3.0 Tesla MRI). Manual segmentation of tumors based on the three-dimensional T1W images was performed by two observers to appraise the intra- and interobserver variability. After radiomic features and tumor-to-bone distance were extracted, it was used to train a machine learning model to distinguish IM lipomas and ALTs/WDLSs. Both feature selection and classification steps were performed using Least Absolute Shrinkage and Selection Operator logistic regression. The performance of the classification model was assessed using a tenfold cross-validation strategy and subsequently evaluated using the receiver operating characteristic curve (ROC) analysis. The classification agreement of two experienced musculoskeletal (MSK) radiologists was assessed using the kappa statistics. The diagnosis accuracy of each radiologist was evaluated using the final pathological results as the gold standard. Additionally, we compared the performance of the model and two radiologists in terms of the area under the receiver operator characteristic curves (AUCs) using the Delong's test. RESULTS: There were 68 tumors (38 IM lipomas and 30 ALTs/WDLSs). The AUC of the machine learning model was 0.88 [95% CI 0.72-1] (sensitivity, 91.6%; specificity, 85.7%; and accuracy, 89.0%). For Radiologist 1, the AUC was 0.94 [95% CI 0.87-1] (sensitivity, 97.4%; specificity, 90.9%; and accuracy, 95.0%), and as to Radiologist 2, the AUC was 0.91 [95% CI 0.83-0.99] (sensitivity, 100%; specificity, 81.8%; and accuracy, 93.3%). The classification agreement of the radiologists was 0.89 of kappa value (95% CI 0.76-1). Although the AUC of the model was lower than of two experienced MSK radiologists, there was no statistically significant difference between the model and two radiologists (all P > 0.05). CONCLUSIONS: The novel machine learning model based on tumor-to-bone distance and radiomic features is a noninvasive procedure that has the potential for distinguishing IM lipomas from ALTs/WDLSs. The predictive features that suggested malignancy were size, shape, depth, texture, histogram, and tumor-to-bone distance.

Robustness of Radiomic Features: Two-Dimensional versus Three-Dimensional MRI-Based Feature Reproducibility in Lipomatous Soft-Tissue Tumors.

This retrospective study aimed to compare the intra- and inter-observer manual-segmentation variability in the feature reproducibility between two-dimensional (2D) and three-dimensional (3D) magnetic-resonance imaging (MRI)-based radiomic features. The study included patients with lipomatous soft-tissue tumors that were diagnosed with histopathology and underwent MRI scans. Tumor segmentation based on the 2D and 3D MRI images was performed by two observers to assess the intra- and inter-observer variability. In both the 2D and the 3D segmentations, the radiomic features were extracted from the normalized images. Regarding the stability of the features, the intraclass correlation coefficient (ICC) was used to evaluate the intra- and inter-observer segmentation variability. Features with ICC > 0.75 were considered reproducible. The degree of feature robustness was classified as low, moderate, or high. Additionally, we compared the efficacy of 2D and 3D contour-focused segmentation in terms of the effects of the stable feature rate, sensitivity, specificity, and diagnostic accuracy of machine learning on the reproducible features. In total, 93 and 107 features were extracted from the 2D and 3D images, respectively. Only 35 features from the 2D images and 63 features from the 3D images were reproducible. The stable feature rate for the 3D segmentation was more significant than for the 2D segmentation (58.9% vs. 37.6%, p = 0.002). The majority of the features for the 3D segmentation had moderate-to-high robustness, while 40.9% of the features for the 2D segmentation had low robustness. The diagnostic accuracy of the machine-learning model for the 2D segmentation was close to that for the 3D segmentation (88% vs. 90%). In both the 2D and the 3D segmentation, the specificity values were equal to 100%. However, the sensitivity for the 2D segmentation was lower than for the 3D segmentation (75% vs. 83%). For the 2D + 3D radiomic features, the model achieved a diagnostic accuracy of 87% (sensitivity, 100%, and specificity, 80%). Both 2D and 3D MRI-based radiomic features of lipomatous soft-tissue tumors are reproducible. With a higher stable feature rate, 3D contour-focused segmentation should be selected for the feature-extraction process.

Three-dimensional motion analysis of ten common Asian sitting positions in daily living and factors affect range of hip motions.

BACKGROUND: Sitting involves many activities of daily life and requires most motion in the hip joint. Asians have more hip flexion and external rotation motions than Westerners owing to cultural and lifestyle differences. Being aware of the normal range of hip motion is essential in clinical practice. Limited research has focused on the hip motions of common sitting positions. The objective was to determine the hip motions of 10 common sitting positions, and to determine whether gender or being overweight affects the range of hip motions. METHODS: An experimental cross-sectional study was conducted to determine hip motions by using a standard, three-dimensional, motion-analysis system. Healthy subjects performed 10 sitting positions during 3 trials. All hip-kinematic data were measured on the dominant leg of each participant, except for the right- and left-monk positions (both hips were analyzed). Density plots were constructed and statistical analyses were performed to detect the differences between groups (male and female; non-overweight and overweight). RESULTS: The 48 participants comprised 24 males and 24 females. Most were right-leg dominant (45 participants, 93.8%). Of the 22 participants in the overweight group (body mass index ≥23 kg/m2), 18 (75%) were male. Squatting showed the highest flexion angle (99.7°, 47.3°-122°). Cross-legged sitting had the highest abduction angle (28.9°, 9.9°-45.7°) and the largest external rotation angle (62°, 37.6°-81.7°). In the female group, there were trends toward a greater flexion angle (4 out of 10 sitting positions) and a smaller abduction angle (6 out of 9 positions), with P values < 0.05. As to body weight, the overweight participants had a smaller flexion angle but a greater abduction angle, with 5 out of 9 positions having a P value < 0.05. Kinematic data of the transverse plane revealed that the heterogeneity of the rotational angles depended on the sitting position. CONCLUSIONS: This study provided the functional hip motions of common Asian sitting positions. The kinematic data can be utilized in clinical practice as reference values to determine safe positions. Gender and being overweight affected the hip angles in the sagittal and frontal planes. TRIAL REGISTRATION: Number TCTR20181021004 , retrospectively registered at the Thai Clinical Trials Registry (http//:www.clinicaltrials.in.th).

Comminution plays no role in worsening fracture healing of conservatively treated middle third clavicular fractures.

OBJECTIVE: Middle third clavicular fracture is effectively treated by conservative means. Previous studies showed that comminution and displacement of clavicular fractures might affect fracture healing. However, the clavicle horizontally aligns in the shoulder girdle and has different biomechanics from vertical weight-bearing bones. Therefore, this study was conducted with the hypothesis that comminution has no effect in worsening fracture healing and union configurations in conservatively treated middle third clavicular fractures. METHODS: One hundred ninety-eight middle third clavicular fractures treated by conservative means were reviewed and divided into 2 groups. Group 1, simple fractures, included 97 patients. Group 2, comminuted fractures, included 101 patients. Patient demographic data, initial fracture deformities, and union configurations such as angulation, overlying, and displacement were measured. Union rate and union complications such as delayed nonunion were evaluated. Data were analyzed for statistically significant differences (p<0.05). RESULTS: Initial deformities of Group 1 and Group 2 were 11.94°±9.59° and 9.40°±8.57° angulation, 12.24±12.96 and 11.76±10.06 mm of overlying, and 13.31±8.63 and 13.72±7.42 mm of displacement, respectively, and exhibited no significant differences (p>0.05). Union rate and union complications of Group 1 were 74/97 (76.29%) and 23/97 (23.71%), respectively. For Group 2, the rates were 82/101 (81.19%) and 19/101 (18.81%), respectively. Union configuration of Group 1 and Group 2 were 13.76°±10.63° and 12.80°±8.65° angulation, 11.93±10.75 and 11.52±9.38 mm of overlying, and 9.79±8.33 and 10.74±6.68 mm of displacement, respectively, and showed no significant differences between the groups. CONCLUSION: Comminution plays no role in worsening fracture healing of conservatively treated middle third clavicular fractures in terms of healing rate, union complications, and union configurations.

Vertical pelvic ring displacement in pelvic ring injury: Measurements in pelvic outlet radiograph and in cadavers.

BACKGROUND: Vertical pelvic ring displacement (VPRD) is a serious injury and needs assessment. Pelvic outlet radiographs are routinely taken. However, relationship of radiographic and actual VPRD is still in question. Thus, measurement of VPRD from pelvic radiographs was studied. MATERIALS AND METHODS: 2 dry pelvic bones and 1 sacrum from same cadaver was reconstructed to be the pelvic ring. Five specimens were enrolled. 10, 20 and 30 mm vertical displacement of right pelvic bone was performed at levels of sacroiliac joint and pubic symphysis for representing right VPRD. Then, the pelvis was set sacral inclination at 60° from X-ray table for outlet and anteroposterior pelvic radiographs. Right VPRD was measured by referring to superior most pelvic articular surface of both sacroiliac joints and sacral long axis. Radiographic VPRD and actual displacement were analyzed by Pearson correlation coefficient at more than 0.90 for the strong correlation and strongly significant simple regression analysis was set at P < 0.01. RESULTS: Radiographic VPRD from outlet and anteroposterior pelvic views at 10 mm actual displacement were 20.12 ± 1.98 and 4.08 ± 3.76 mm, at 20 mm were 40.31 ± 1.97 and 9.94 ± 7.27 mm and at 30 mm were 58.56 ± 2.53 and 11.29 ± 2.89 mm. Statistical analyses showed that radiographic VPRD from pelvic outlet view is 1.95 times of actual displacement with strong correlation at 0.992 coefficient and strongly significant regression analysis (P < 0.001) with 0.984 of R (2) value. Whereas, the measurement from anteroposterior pelvic radiograph was not strongly significant. CONCLUSION: Pelvic outlet radiograph provides efficient measurement of VPRD with 2 times of actual displacement.

Measurement technique of calcaneal varus from axial view radiograph.

BACKGROUND: Medial displaced posterior calcaneal tubercle creates varus deformity of an intraarticular calcaneal fracture. The fracture involves posterior calcaneal facet and the calcaneal body so we developed a measurement technique representing the angle between posterior facet and long axis of calcaneus using lateral malleolus and longitudinal bone trabeculae of posterior calcaneal tubercle as references to obtain calcaneal varus angle. MATERIALS AND METHODS: 52 axial view calcaneal radiographs of 26 volunteers were studied. Angles between posterior facet and long axis of calcaneus were measured using the measurements 1 and 2. Angle of measurement 1, as gold standard, was obtained from long axis and posterior facet of calcaneus whereas measurement 2 was obtained from a line, perpendicular to apex curve of lateral cortex of the lateral malleolus and a line parallel to the longitudinal bone trabeculae of posterior calcaneal tubercle. No more than 3° of difference in the angle of both measurements was accepted. Reliability of the measurement 2 was statistically tested. RESULTS: Angles of measurement 1 and 2 were 90.04° ± 4.00° and 90.58° ± 3.78°. Mean of different degrees of both measurements was 0.54° ± 2.31° with 95% of confidence interval: 0.10°-1.88°. The statistical analysis of measurement 1 and 2 showed more than 0.75 of ICC and 0.826 of Pearson correlation coefficient. CONCLUSION: Technique of measurement 2 using lateral malleolus and longitudinal bone trabeculae of posterior calcaneal tubercle as references has strong reliability for representing the angle between long axis and posterior facet of calcaneus to achieve calcaneal varus angle.

Acetabular roof arc angles and anatomic biomechanical superior acetabular weight bearing area.

BACKGROUND: Acetabular fracture involves whether superior articular weight bearing area and stability of the hip are assessed by acetabular roof arc angles comprising medial, anterior and posterior. Many previous studies, based on clinical, biomechanics and anatomic superior articular surface of acetabulum showed different degrees of the angles. Anatomic biomechanical superior acetabular weight bearing area (ABSAWBA) of the femoral head can be identified as radiographic subchondral bone density at superior acetabular dome. The fracture passes through ABSAWBA creating traumatic hip arthritis. Therefore, acetabular roof arc angles of ABSAWBA were studied in order to find out that the most appropriate degrees of recommended acetabular roof arc angles in the previous studies had no ABSAWBA involvement. MATERIALS AND METHODS: ABSAWBA of femoral head was identified 68 acetabular fractures and 13 isolated pelvic fractures without unstable pelvic ring injury were enrolled. Acetabular roof arc angle was measured on anteroposterior, obturator and iliac oblique view radiographs of normal contralateral acetabulum using programmatic automation controller digital system and measurement tools. RESULTS: Average medial, anterior and posterior acetabular roof arc angles of the ABSAWBA of 94 normal acetabulum were 39.09 (7.41), 42.49 (8.15) and 55.26 (10.08) degrees, respectively. CONCLUSIONS: Less than 39°, 42° and 55° of medial, anterior and posterior acetabular roof arc angles involve ABSAWBA of the femoral head. Application of the study results showed that 45°, 45° and 62° from the previous studies are the most appropriate medial, anterior and posterior acetabular roof arc angles without involvement of the ABSAWBA respectively.

Posterior acetabular arc angle of unstable posterior hip fracture-dislocation.

PURPOSE: Posterior hip fracture-dislocation needs stability evaluation. A previous study in the normal acetabulum has shown that the coronal posterior acetabular arc angle (PAAA) could be used to assess an unstable posterior hip fracture. Our study was designed to assess PAAA of unstable posterior hip fracture-dislocation and whether posterior acetabular wall fracture involves the superior acetabular dome. METHODS: Using coronal computed tomography (CT) of the acetabulum and 3D reconstruction of the lateral pelvis, we measured coronal, vertical PAAA and posterior acetabular wall depth of 21 unstable posterior hip fracture-dislocations and of 50% normal contralateral acetabula. Posterior acetabular wall fracture was assessed to determine whether the fracture involved the superior acetabular dome and then defined as a high or low wall fracture using vertical PAAA in reference to the centroacetabulo-greater sciatic notch line. RESULTS: The coronal PAAA of unstable posterior hip fracture-dislocations and of 50% of the posterior acetabular wall of normal the contralateral acetabulum were 54.48° (9.09°) and 57.43° (5.88°) and corresponded to 15.06 (4.39) and 15.61 (2.01) mm of the posterior acetabular wall without significant difference (p > 0.05). The vertical PAAA of unstable posterior hip fracture-dislocation was 101.67° (20.44°). There were 16 high posterior acetabular wall fractures with 35.00 (16.18) vertical PAAA involving the acetabular dome and 5 low wall fractures. High posterior wall fractures resulted in four avascular necroses of the femoral head, three sciatic nerve injuries and one osteoarthritic hip. CONCLUSION: Coronal and vertical PAAA of unstable posterior hip fracture-dislocations were 54.48° and 101.67°. Vertical PAAA assesses high or low posterior acetabular wall fracture by referring to the centroacetabulo-greater sciatic notch line. High posterior wall fracture seems to be the most frequent and is involved with many complications.

The anatomical safe zone for medial opening oblique wedge high tibial osteotomy.

INTRODUCTION: The end of medial opening oblique wedge high tibial osteotomy (HTO) points into a narrow area between the articular cartilage of the posterolateral proximal tibia and proximal tibiofibular joint (PTFJ) at the tibial site, which is an anatomical safe zone (ASZ) for osteotomy. We studied the ASZ and its relation to the fibular tip, including the level of posterior cruciate ligament (PCL) insertion, to avoid penetration into the knee and PTFJ, and PCL injury by osteotomy. METHODS: Ten pairs of embalmed cadaveric legs were disarticulated at the knee joint and then examined. Soft tissues at the proximal tibia were removed. The posterior capsule of the PTFJ was incised to identify the articular cartilage of the PTFJ at the tibial site. The height of the fibular tip and the thickness of the ASZ were measured and calculated to determine the relationship between the ASZ and fibular tip. The level of PCL insertion was measured from the posterior articular surface of the proximal tibia to the distal attachment of the PCL. RESULTS: The average height of the fibular tip and the thickness of the ASZ were 5.43 ± 1.53 mm and 4.12 ± 1.60 mm, respectively. On average, the fibular tip was 1.31 ± 1.28 mm higher than the ASZ, and the level of PCL insertion was 10.10 ± 1.88 mm. CONCLUSION: To ensure safety during medial opening oblique wedge HTO, the end of osteotomy should point accurately into the ASZ at a level just below the fibular tip as reference. Proximal osteotomy thickness should not be less than 10 mm at the level of PCL insertion.

Displaced articular calcaneus fractures: classification and fracture scores: a preliminary study.

OBJECTIVE: To review and group configurations of displaced articular calcaneal fracture advantaged for classification and radiographic fracture scores. MATERIAL AND METHOD: Between 2002 and 2011, medical records and radiographs of patients who sustained acute displaced articular calcaneal fractures were reviewed. The calcanealfracture configurations were grouped as avulsion, bending, burst, or combination. Radiographic displaced articular calcaneal fracture score was designed to include Bohler and Gissane angles, degrees of posterior subtalar joint line parallel, degrees of varus, and burst. The calcaneal fracture score was modified as power of the fracture response to treatment (PFRT). Prevalence of the fracture types, pre- and post-reduction fracture scores including PFRT were studied and statistically analyzed. RESULTS: Sixty-four patients had 77 acute displaced articular calcaneal fractures. The classification consisted of type I avulsion, type II compression bending, type III compression burst, type IV avulsion burst, and type V bending burst. Type IV is the most common. The radiographic calcaneal fracture scores were 10 points. Pre-, post-reduction calcaneal fracture scores and PFRTof type I, II, III, IV, and V were 4.17 (0.41), 0 and 1 (0), 4.63 (2.13), 0.50 (0.93) and 0.84 (0.35), 6.94 (2.05), 3.18 (1.38) and 0.50 (0.27), 8.03 (1.12), 3.03 (2.42) and 0.62 (0.30), and 7.22 (2.11), 3.00 (2.50) and 0.59 (0.29) respectively. Statistical analysis showed significant difference (p < 0.05). PFRT for screw and pin fixation of type I plus II, IV and V were 1.00 (0) and 1.00 (0), 0.64 (0.27) and 0.60 (0.36), and 0.54 (0.28) and 0.51 (0.45) respectively. PFRT for plate of type III was 0.54 (0.16). PFRT for casting of type I plus II, III, and IV were 0.50 (0.71), 0.27 (0.46), and 0.35 (0.33) respectively. CONCLUSION: The classification consisted of five types, which were based on injury mechanisms as avulsion, bending, and burst. The radiographic calcaneal fracture scores contained 10 points and were used for determining complexity of the fractures. PFRT was used for evaluating efficacy of fracture treatment.

The second fracture of the same clavicle: prevalence and fracture configurations.

OBJECTIVE: To study second fracture at the same clavicle including prevalence, fracture configurations related to malunion types of the first fracture, and healing. MATERIAL AND METHOD: Between 2008 and 2011, the authors reviewed medical records and radiographs of the clavicles of patients who sustained acute clavicular fractures from motorcycle accident. Second fracture at the same clavicle and prevalence were studied. Malunion of the first fracture of the same clavicle were typed and configurations of the second fracture at the same clavicles were described related to type of the malunion. RESULTS: There were 552 clavicular fractures. Four cases of which sustained a second fracture at the same clavicles. Malunion of the first clavicular fracture of the four cases were typed: type I, extension, type II, flexion, and type III, bayonet. There were one, two, and one case of second clavicular fractures of the type I, II, and III clavicular malunion. The configuration of second clavicular fracture of the type I malunion clavicle is located at lateral fragment, inferior displacement, and dorsal angulation with dorsal cortex conminution. The type II malunion clavicle is located at lateral fragment with minimal displacement. For the type III malunion clavicle, the second fracture is located at medial fragment with mild inferior displacement and inferior angulation. The four cases of the second fractures of the same clavicles healed within two months without complication. CONCLUSION: The prevalence of second fracture at the same clacicles was 7.2:1000. The three types of the first fracture malunion were extension, flexion, and bayonet. The configuration of the second fracture at the same clavicles depends on malunion types of the first clavicular fracture. They healed without complication.