In this paper, we propose a method to achieve improved number plate detection for mobile devices by applying a multiple convolutional neural network (CNN) approach. First, we processed supervised ...CNNverified car detection and then we applied the detected car regions to the next supervised CNN-verifier for number plate detection. In the final step, the detected number plate regions were verified through optical character recognition by another CNN-verifier. Since mobile devices are limited in computation power, we are proposing a fast method to recognize number plates. We expect for it to be used in the field of intelligent transportation systems. KCI Citation Count: 0
There is a broad spectrum of complications during or after surgical procedures, with differing incidences reported in the published literature. Heterogeneity can be explained by the lack of an ...established evidence-based classification system for documentation and classification of complications in a standardized manner.
The objective of this study was to identify predictive risk factors for perioperative and early postoperative morbidities in spine surgeries of different complexities in a large cohort of consecutive patients.
This study is a retrospective case series.
The outcome measures are the occurrence of perioperative and early postoperative morbidities.
A classification of surgical complexity (Grades I–III) was created and applied to 1,009 patients who consecutively underwent spine surgery at a single university hospital. The incidence and the type of perioperative and early postoperative morbidities were documented. Multivariate binary logistic regression analyzed risk factors for (1) hospital stay of ≥10 days, (2) intermediate care unit (IMC) stay of ≥24 hours, (3) blood loss of >500 mL, and occurrence of a (4) surgical or (5) medical morbidity.
A deviation from the regular postoperative course (defined as “morbidity”) included surgical reasons, such as relapse of symptoms of any kind (3.3%), wound healing problems (2.4%), implant-associated complications (1.6%), postoperative neurologic deficits (1.5%), infection (1.5%), fracture (0.8%), and dural tear in need of revision (0.6%). Medical reasons included anemia (1.8%), symptomatic electrolyte derailment (1.0%), and cardiac complications (0.7%), among others. An independent risk factor associated with a surgical reason for an irregular postoperative course was male gender. Risk factors associated with a medical reason for an irregular postoperative course were identified as preoperatively high creatinine levels, higher blood loss, and systemic steroid use. Independent risk factors for a prolonged hospitalization were preoperatively high C-reactive protein level, prolonged postoperative IMC stay, and revision surgery. Spinal stabilization or fusion surgery, particularly if involving the lumbosacral spine, age, and length of surgery were associated with blood loss of >500 mL. Higher surgical complexity, involvement of the pelvis in instrumentation, American Society of Anesthesiologists Grade ≥III, and preoperatively higher creatinine levels were associated with a postoperative IMC stay of >24 hours.
The present study confirms several modifiable and non-modifiable risk factors for perioperative and early postoperative morbidities in spine surgery, among which surgical factors (such as complexity, revision surgery, and instrumentation, including the pelvis) play a crucial role. A classification of surgical complexity is proposed and validated.
Shoulder instabilities have been classified according to the etiology, the direction of instability, or on combinations thereof. The current authors describe a classification system, which ...distinguishes between static instabilities, dynamic instabilities, and voluntary dislocation. Static instabilities are defined by the absence of classic symptoms of instability and are associated with rotator cuff or degenerative joint disease. The diagnosis is radiologic, not clinical. Dynamic instabilities are initiated by a trauma and may be associated with capsulolabral lesions, defined glenoid rim lesions, or with hyperlaxity. They may be unidirectional or multidirectional. Voluntary dislocation is classified separately because dislocations do not occur inadvertently but under voluntary control of the patient.
Background In the presence of severe osteoarthritis, osteonecrosis, or proximal humeral fracture, the contralateral humerus may serve as a template for the 3-dimensional (3D) preoperative planning of ...reconstructive surgery. The purpose of this study was to develop algorithms for performing 3D measurements of the humeral anatomy and further to assess side-to-side (bilateral) differences in humeral head retrotorsion, humeral head inclination, humeral length, and humeral head radius and height. Methods The 3D models of 140 paired humeri (70 cadavers) were extracted from computed tomographic data. Geometric characteristics quantifying the humeral anatomy in 3D were determined in a semiautomatic fashion using the developed computer algorithms. The results between the sides were compared for evaluating bilateral differences. Results The mean bilateral difference of the humeral retrotorsion angle was 6.7° (standard deviation SD, 5.7°; range, −15.1° to 24.0°; P = .063); the mean side difference of the humeral head inclination angle was 2.3° (SD, 1.8°; range, −5.1° to 8.4°; P = .12). The side difference in humeral length (mean, 2.9 mm; SD, 2.5 mm; range, −8.7 mm to 10.1 mm; P = .04) was significant. The mean side difference in the head sphere radius was 0.5 mm (SD, 0.6 mm; range, −3.2 mm to 2.2 mm; P = .76), and the mean side difference in humeral head height was 0.8 mm (SD, 0.6 mm; range, −2.4 mm to 2.4 mm; P = .44). Conclusions The contralateral anatomy may serve as a reliable reconstruction template for humeral length, humeral head radius, and humeral head height if it is analyzed with 3D algorithms. In contrast, determining humeral head retrotorsion and humeral head inclination from the contralateral anatomy may be more prone to error.
A large critical shoulder angle (CSA) >35° is associated with the development of rotator cuff tearing. Lateral acromioplasty (AP) has the theoretical potential to prevent rotator cuff tearing and/ or ...to reduce the risk of re-tears after repair. It is, however unclear which part of the lateral acromion has to be reduced to obtain the desired CSA. It was the purpose of this study to determine which part of the lateral acromion has to be resected to achieve a desired reduction of the CSA in a given individual.
First, the influence of the exact radiographic projection on the CSA was examined. Second, the influence of anterolateral versus strict lateral AP on the CSA was studied in eight scapulae with different anatomic characteristics. Differences in CSA reduction were investigated using paired t-test or Wilcoxon test.
Scapular rotation in the sagittal and axial plane had a marked influence on the radiologically measured CSA ranging from -6 to +16°. Overall, lateral AP of 5/10mm reduced the CSA significantly greater than anterolateral AP of 5mm/10mm 5mm: 2.3° (range: 0.7°-3.6°) SD±0.8° vs. 1.2° (range: 0°-3.3°) SD±1.1°, p=0.0002/10mm: 4.8° (range: 2.1°-7°) SD±1.3° vs. 2.7° (range: 0°-5.3°) SD±1.7°, p=0.0001. Depending on scapular anatomy anterolateral AP did not alter CSA at all.
For comparison of pre- and postoperative CSA, the exact orientation of the X-ray and the spatial orientation of the scapula must be as identical as possible. Anterolateral AP may not sufficiently correct CSA in scapulae with great acromial slopes and smaller relative external rotation of the acromion as the critical acromial point (CAP) may be located too posteriorly and thus is not addressed by anterolateral acromioplasty. Consistent reduction of the CSA could be achieved by lateral AP in all eight scapulae.
Most studies demonstrated, that training on a virtual reality based arthroscopy simulator leads to an improvement of technical skills in orthopaedic surgery. However, how long and what kind of ...training is optimal for young residents is unknown. In this study we tested the efficacy of a standardized, competency based training protocol on a validated virtual reality based knee- and shoulder arthroscopy simulator.
Twenty residents and five experts in arthroscopy were included. All participants performed a test including knee -and shoulder arthroscopy tasks on a virtual reality knee- and shoulder arthroscopy simulator. The residents had to complete a competency based training program. Thereafter, the previously completed test was retaken. We evaluated the metric data of the simulator using a z-score and the Arthroscopic Surgery Skill Evaluation Tool (ASSET) to assess training effects in residents and performance levels in experts.
The residents significantly improved from pre- to post training in the overall z-score: - 9.82 (range, - 20.35 to - 1.64) to - 2.61 (range, - 6.25 to 1.5); p < 0.001. The overall ASSET score improved from 55 (27 to 84) percent to 75 (48 to 92) percent; p < 0.001. The experts, however, achieved a significantly higher z-score in the shoulder tasks (p < 0.001 and a statistically insignificantly higher z-score in the knee tasks with a p = 0.921. The experts mean overall ASSET score (knee and shoulder) was significantly higher in the therapeutic tasks (p < 0.001) compared to the residents post training result.
The use of a competency based simulator training with this specific device for 3-5 h is an effective tool to advance basic arthroscopic skills of resident in training from 0 to 5 years based on simulator measures and simulator based ASSET testing. Therefore, we conclude that this sort of training method appears useful to learn the handling of the camera, basic anatomy and the triangulation with instruments.
Background Little is known of the mechanisms that lead to the muscle changes associated with rotator cuff disorders. We have observed that the magnetic resonance imaging (MRI) appearance of fatty ...infiltration (FI) and muscle atrophy (MA) differ between chronic cuff tears and suprascapular neuropathy, suggesting different pathophysiology. This study compares the different MRI changes that occur in chronic cuff tears and suprascapular neuropathy. Methods Two groups were retrospectively identified: (1) RCT group (20 shoulders): patients with chronic tears of the supraspinatus and/or infraspinatus without electromyographic (EMG) evidence of suprascapular neuropathy; (2) neuro group (17 shoulders): patients with EMG documented suprascapular nerve dysfunction and absence of a rotator cuff tear. Magnetic resonance arthrograms were analyzed for the degree of FI and MA, and the morphology of the muscle was assessed, in particular the muscle border, pattern of FI, and extent of involvement. Results The muscle changes that occur following chronic cuff tears differ from that following denervation secondary to suprascapular neuropathy, especially with respect to the muscle border, degree of perineural fat, and overall distribution of FI. Highly specific and characteristic morphological patterns of FI exist for both chronic cuff tears and suprascapular neuropathy. Conclusion Chronic rotator cuff tendon tears and suprascapular neuropathy are both associated with FI and MA of the rotator cuff muscles. The pattern of FI is markedly different in the 2 situations. These findings have diagnostic potential and may serve as a basis for further research concerning type, severity, and evolution of FI under different conditions and after treatment.
Purpose
Glenohumeral osteoarthritis (OA) represents a challenging problem in young, physically active patients. It was the purpose of this investigation to evaluate the results of a pilot study ...involving glenoid resurfacing with a glenoid allograft combined with a hemiarthroplasty on the humeral side.
Methods
Between April 2011 to November 2013, 5 patients (3 men, 2 women, mean age 46.4, range 35-57) with advanced OA of the glenohumeral joint, were treated with a humeral head replacement combined with replacement of the glenoid surface with an osteochondral, glenoid allograft.
Results
Overall, clinically, there was one excellent, one satisfactory and three poor results. Mean preoperative subjective shoulder value (SSV) was 34% (range: 20-50%) and preoperative relative Constant-Murley-Score (CSr) was 43 points (range: 29-64 points). Three patients with poor results had to be revised within the first three years. Their mean pre-revision SSV and CSr were 38% (range: 15-80%) and 36 points (range: 7-59 points) respectively. One patient was revised 9 years after the primary procedure with advanced glenoid erosion and pain and one patient has an ongoing satisfactory outcome without revision. Their SSVs were 60% and 83%, their CSr were 65 points and 91 points, 9 and 10 years after the primary procedure, respectively. Mean follow-up was 7 years (2-10 years) and mean time to revision was 4 years (range: 1-9 years).
Conclusion
The in-vivo pilot study of a previously established in-vitro technique of osteochondral glenoid allograft combined with humeral HA led to three early failures and only one really satisfactory clinical outcome which, however, was associated with advanced glenoid erosion. Osteochondral allograft glenoid resurfacing was associated with an unacceptable early failure rate and no results superior to those widely documented for HA or TSA, so that the procedure has been abandoned.
Level of evidence
Level IV, Case Series, Treatment Study.
BackgroundReports have demonstrated that reverse shoulder arthroplasty restores overhead elevation but fails to restore active external rotation. The teres minor muscle-tendon unit contributes to ...active external rotation, and its deficiency may impair the clinical outcome. It was therefore the purpose of this study to evaluate the influence of fatty infiltration of the teres minor muscle on the clinical outcome after reverse total shoulder replacement.MethodsForty-two shoulders in forty-two patients (average age, seventy-one years) with painful cuff tear arthropathy or an irreparable rotator cuff deficiency with pseudoparesis were treated with a reverse Delta-III shoulder arthroplasty and followed clinically for a minimum of twenty-four months. Preoperatively, fatty infiltration of the teres minor was assessed, according to the grading system of Goutallier et al., with use of magnetic resonance imaging. The effect of teres minor fatty infiltration on the subjective and objective outcomes of the reverse shoulder arthroplasty was evaluated.ResultsThe thirty shoulders with stage-0, 1, or 2 fatty infiltration of the teres minor muscle (group 1) had a significantly better ultimate Constant score, a significantly better subjective shoulder value, and significantly greater preoperative-to-postoperative improvement than the twelve shoulders with stage-3 or 4 fatty infiltration (group 2). In group 1 the relative Constant score increased by an average of 41% and the subjective shoulder value increased by an average of 44%, whereas in group 2 the respective increases were 32% (p = 0.033) and 25% (p = 0.018). Group 1 had an average increase of 6.2 points in the score for extremity positioning, whereas group 2 gained only 5.3 points (p = 0.033). Group 1 had a net gain of 9° of external rotation with the arm at the side compared with an average net loss of 7° in group 2 (p < 0.001).ConclusionsStage-3 or 4 fatty infiltration of the teres minor compromises the clinical outcome of reverse shoulder arthroplasty for the treatment of irreparable rotator cuff tears.Level of EvidencePrognostic Level II. See Instructions to Authors for a complete description of levels of evidence.
Optimal radii of curvature of the articulating surfaces of the prosthetic components are factors associated with the longevity of cemented glenoid components in anatomical total shoulder ...arthroplasty. It was the purpose of this study, to evaluate the radiographic and clinical performance of an anatomical glenoid component of a total shoulder arthroplasty (TSA) with respect to radial mismatch of the glenoid and humeral component.
In a retrospective study 75 TSA were analyzed for their clinical and radiographic performance with computed tomography by independent examiners using an established methodology. The study group was divided in two groups, one with mismatch < 4.5 mm (n:52) the others with mismatch ≥4.5 mm (n:23) and analyzed for confounding variables as indication, primary or revision surgery, age, gender, glenoid morphology and implant characteristics.
The mean glenohumeral radial mismatch was 3.4 mm (range 0.5-6.9). At median follow-up of 41 months (range 19-113) radiographic loosening (defined as modified Molé scores ≥6) was present in 7 cases (9.3%). Lucencies around the glenoid pegs (defined as modified Molé score ≥ 1) were present in 34 cases (45%). Radiolucencies were significantly associated with a radial mismatch < 4.5 mm (p = 0.000). The pre- to postoperative improvements in Subjective Shoulder Value and absolute Constant Score were significantly better in the group with a mismatch ≥4.5 mm (p = 0.018, p = 0.014).
A lower conformity of the radii of humerus and glenoid seems to improve the loosening performance in TSA. Perhaps cut-off values regarding the recommended mismatch need to be revalued in the future.
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