True Anteroposterior View Research Articles

Interobserver reliability of shoulder radiographic findings and correlation to MRI: a preliminary case series.

The aim of this study was to evaluate the interobserver reliability of measurements of the Acromiohumeral Distance (AHD) first described by Golding et al., the Critical Shoulder Angle (CSA), the Acromion Index with Glenoid Humeral (GH) and Glenoid Acromial (GA) distances, following the measuring method by Nyffeler et al., the Lateral Acromion Angle (LAA), as well as the morphology of the acromion according to Bigliani and the humeral head position according to Maloney in X-rays and MRI. Furthermore, the study assessed the correlation of measurement results in X-ray with those in MRI for AHD, CSA, GA, GH, AI, and LAA. A total of 187 patients who underwent shoulder joint X-ray and MRI examinations from 09/2016 to 05/2023 were included in the study. Patients with poor imaging quality, arthrosis or radical prior surgeries, like shoulder prosthetic surgery, status post humerus fractures, that have undergone surgery and therefore changed the anatomical features were excluded, what lead to a total study population of 78. X-ray measurements were performed by two observers in the true anteroposterior view, so that the humeral head and the glenoid are shown without overlap, providing a clear view into the joint space. MRI measurements were performed in oblique coronal MRI slices, using the most accurately depicted glenoid surface as a landmark. Interobserver measurement results showed a significance with p < 0.001 for the assessment of acromion type according to Bigliani, humeral head offset assessment according to Maloney, and AHD. No significance was found for interobserver reliability in measuring LAA. Additionally, there was a high correlation of measurement results in X-ray with measurements in MRI for, CSA, GH/GA, and consequently AI, a good correlation for AHD but no correlation could be shown for LAA. These findings provide valuable insights into the robustness of radiological parameters for evaluating shoulder pathology, offering promising prospects for clinical applications and further research. Nevertheless, the specific methodological considerations and patient characteristics should be taken into account when interpreting the results to ensure their accurate application in clinical practice.

Are acromiohumeral distance measurements on conventional radiographs reliable? A prospective study of inter-method agreement with ultrasonography, and assessment of observer variability.

This study aims to investigate the reliability of acromiohumeral distance (AHD) measurements using conventional radiographs and to compare non-standardized and standardized radiographs with intra-/interobserver reliability measurements. Between February 2021 and January 2022, a total of 110 shoulders of 55 patients (25 males, 30 females; mean age: 49.7±12.6 years; range, 25 to 77 years) were included. Radiographs were taken in four different positions: primarily shoulder anteroposterior (AP), true AP, standardized true AP, and standardized outlet views. The AHD was measured by three orthopedists. A prospective ultrasonography (US) evaluation was performed by an experienced physiatrist, and the relationship between US and radiographic measurements was evaluated. The intra- and interobserver reliability of radiographic measurements was assessed. On the standardized true AP view measurements, all observers showed a moderate to good agreement with US measurements (intraclass correlation coefficients [ICC]: 0.68-0.75). There was no significant difference between the AHD measurements of the senior orthopedist on standardized true AP and outlet views, and the US measurements. The intraobserver agreement of US measurements was excellent (ICC: 0.98, 95% confidence interval [CI]: 0.98-0.99), and the intraobserver agreement level of measurements on radiographs were good to excellent with a wide range of ICC values (ICC: 0.79-0.97). Interobserver reliability was the highest on the standardized outlet view, with an ICC of 0.91 and 0.88 in two measurement times. Interobserver reliability of other measurements were good with ICC values ranging from 0.82 to 0.88. The AHD measurements on radiographs are compatible with US measurements within up to 2 mm difference if standardization is ensured. Also, measurements on standardized views have a superior consistency with lower standard error of measurement and minimal detectable change values. Therefore, we recommend using standardized true shoulder AP and standardized outlet radiographs in clinical practice and studies, as these are the most accurate in demonstrating true AHD.

Deep learning-based screening tool for rotator cuff tears on shoulder radiography

BackgroundEarly diagnosis of rotator cuff tears is essential for appropriate and timely treatment. Although radiography is the most used technique in clinical practice, it is difficult to accurately rule out rotator cuff tears as an initial imaging diagnostic modality. Deep learning-based artificial intelligence has recently been applied in medicine, especially diagnostic imaging. This study aimed to develop a deep learning algorithm as a screening tool for rotator cuff tears based on radiography. MethodsWe used 2803 shoulder radiographs of the true anteroposterior view to develop the deep learning algorithm. Radiographs were labeled 0 and 1 as intact or low-grade partial-thickness rotator cuff tears and high-grade partial or full-thickness rotator cuff tears, respectively. The diagnosis of rotator cuff tears was determined based on arthroscopic findings. The diagnostic performance of the deep learning algorithm was assessed by calculating the area under the curve (AUC), sensitivity, negative predictive value (NPV), and negative likelihood ratio (LR−) of test datasets with a cutoff value of expected high sensitivity determination based on validation datasets. Furthermore, the diagnostic performance for each rotator cuff tear size was evaluated. ResultsThe AUC, sensitivity, NPV, and LR− with expected high sensitivity determination were 0.82, 84/92 (91.3%), 102/110 (92.7%), and 0.16, respectively. The sensitivity, NPV, and LR− for full-thickness rotator cuff tears were 69/73 (94.5%), 102/106 (96.2%), and 0.10, respectively, while the diagnostic performance for partial-thickness rotator cuff tears was low at 15/19 (78.9%), NPV of 102/106 (96.2%) and LR− of 0.39. ConclusionsOur algorithm had a high diagnostic performance for full-thickness rotator cuff tears. The deep learning algorithm based on shoulder radiography helps screen rotator cuff tears by setting an appropriate cutoff value. Level of evidenceLevel III: Diagnostic Study.

Quantification of joint space width with different grades of manual traction in patients with adhesive capsulitis-A fluoroscopic study

Adhesive capsulitis causes adaptive shortening of the non-contractile structures around the shoulder joint which may affect the distraction distance or joint space width (JSW) between the glenoid and humeral head. Joint traction is a commonly used manual therapy technique to reduce pain and gain range of motion in patients with adhesive capsulitis. However, changes in JSW with manual traction are not objectively assessed. This study aimed to find differences in shoulder JSW with different grades of traction and made comparisons between the affected and the unaffected side using 2D fluoroscopy. Forty-one subjects (24 males, 17 females; age 53.9±7.9 years) diagnosed with adhesive capsulitis with low to moderate joint irritability were included. Their mean duration of symptoms was 5.25±1.7 months. True anteroposterior view images of the shoulder were taken with the patient in a supine position with their arms held at 75° of abduction. Images of the affected and unaffected side were taken while no traction, grade 2 and grade 3 manual traction were applied. The JSW was determined as the linear distance between the articular surfaces. Repeated measures ANOVA with post hoc testing was used for analysing differences across the sides (affected and unaffected side) and conditions (No, grade 2 and grade 3 traction). There was no significant interaction between conditions and sides (P=0.99). Averaged across sides, the JSW with grade 2 or 3 traction was 0.18 and 0.23 mm more than the no traction condition (P=0.013 and P=0.001, respectively). There were no differences in the JSW with grade 2 or 3 traction. Averaged across the conditions, the JSW on the unaffected side was 0.21 mm more than the affected side (P=0.03). The study demonstrates that adhesive capsulitis causes a reduction in JSW at 75° abducted position and grade 2 or 3 manual traction can significantly increase this JSW. Clinical Trial Registry India: CTRI/2018/12/016657.

Reliability and accuracy of the critical shoulder angle measured by anteroposterior radiographs: using digitally reconstructed radiograph from 3-dimensional computed tomography images

Accuracy of current standard radiographic measurement of the critical shoulder angle (CSA) is not well established. This study analyzed the reliability and accuracy of the CSA measurements obtained via anteroposterior (AP) radiographs, using a digitally reconstructed radiograph (true AP view) generated from a computed tomography image as the gold standard. The CSA was measured on the radiographs and true AP views of 88 consecutive patients who had undergone shoulder arthroscopy for rotator cuff tears. Intraobserver and interobserver reliabilities of the CSA, measured by 2 orthopedic surgeons, were evaluated, and the average deviation of the CSA between radiographs and true AP views was calculated. Moreover, we compared the deviation of CSA between standard AP films (types A1 and C1) and nonstandard AP films (other types) against the Suter-Henninger criteria. Intraobserver and interobserver reliabilities were almost perfect on radiographs (0.96, 0.86) and true AP views (0.93, 0.85). The average deviation of CSA was 2.1°±1.6° for observer 1 and 2.2°±1.9° for observer 2. The percentage of cases with deviations of 2° or more when compared with the true AP view was 42% (37 of 88) for observer 1 and 53% (47 of 88) for observer 2. Only 22% (19 of 88) of films were standard AP films. The average deviation of CSA was not significantly different between standard and nonstandard AP films for observer 1 (standard 1.9°±1.3°; nonstandard 2.1°±1.7°; P=.76) and observer 2 (standard 1.6°±1.5°; nonstandard 2.4°±1.9°; P=.09). The CSA measurements using radiography were highly congruent, but a large measurement deviation occurred between radiographs and true AP views. The clinical usefulness and role of CSA in diagnosis require careful consideration.

Fluoroscopic measurements of the glenohumeral joint position and space in true anteroposterior and axillary views – a reliability study

Two-dimensional (2D) fluoroscopy has been used in shoulder pathologies to estimate the humeral head position (HHP) in the true anteroposterior (AP) view. However, there is a lack of evidence regarding the reliability estimating it in the axillary view and in measuring the shoulder joint space width (JSW). True AP view images (n=36) of subjects with adhesive capsulitis were taken in supine in multiple arm abduction positions. The axillary view images (n=48) were taken in supine and prone in 75° of abduction. The HHP was assessed in the glenoid reference frame. The position and radius of the humeral head along with the superior, inferior, anterior, posterior, and middle JSWs were measured in each image. All the images were coded and randomly presented twice to a physiotherapist at a gap of 48-72 h for intra-rater reliability and to 2 therapists and an orthopaedic surgeon for inter-rater reliability. Reliability was expressed using intraclass correlation coefficients (ICC) and standard error of measurement (SEM). In both the views, inter-rater, and intra-rater reliability was excellent for the radius of the humeral head (inter-rater – 0.95-0.97 and intra-rater -0.98)], moderate (ICC: 0.70 and 0.76), and excellent (ICC: 0.89 and 0.93) for HHP. The reliability for JSWs was moderate to good (ICC: 0.66-0.82) for inter-rater and good to excellent (ICC: 0.75-0.95) for intra-rater analysis. The SEM for HHP and JSWs were &lt;0.4 mm for intra-rater analysis, and &lt;0.7 mm for inter-rater reliability in both views. The study demonstrated that the glenohumeral arthrokinematic parameters can be measured with good to excellent levels of reliability when using 2 D fluoroscopy. The study is part of a clinical trial (Clinical Trial Registry India: CTRI/2018/12/016657).

Inter-rater agreement among shoulder surgeons on treatment options for proximal humeral fractures among shoulder surgeons.

BackgroundThe treatment approach for proximal humeral fractures is determined by various factors, including patient age, sex, dominant arm, fracture pattern, presence of osteoporosis, preexisting arthritis, rotator cuff status, and medical comorbidities. However, there is a lack of consensus in the literature regarding the optimal treatment for displaced proximal humeral fractures. This study aimed to assess and quantify the decision-making process for either conservative or surgical treatment and the choice of surgical method among shoulder surgeons when treating proximal humeral fractures.MethodsForty sets of true anteroposterior view, scapular Y projection view, and three-dimensional computed tomography of proximal humeral fractures were provided to 12 shoulder surgeons along with clinical information. Surveys regarding Neer classification, decisions between conservative and surgical treatments, and chosen methods were conducted twice with an interval of 2 months. The factors affecting the treatment plans were also assessed.ResultsThe inter-rater agreement was fair for Neer classification (kappa=0.395), moderate for the decision between conservative and surgical treatments (kappa=0.528), and substantial for the chosen method of surgical treatment (kappa=0.740). The percentage of agreement was 71.1% for Neer classification, 84.6% for the decision between conservative and surgical treatment, and 96.4% for the chosen method of surgical treatment. The fracture pattern was the most crucial factor in deciding between conservative and surgical treatments, followed by age and physical activity.ConclusionsThe decision between conservative and surgical treatment for proximal humeral fractures showed good agreement, while the chosen method between osteosynthesis and arthroplasty showed substantial agreement among shoulder surgeons.

Axial view of the shoulder. Description of a technique

Shoulder fracture is one of the most frequently treated injuries in trauma centers, with an overall incidence that appears to have increased in recent years, ranging from 219 to 419 cases per 100 000 person-years.In clinical terms, shoulder girdle injury is difficult to diagnose due to the close relationship between the shoulder and the chest, and imaging identification of the different types of injuries can be challenging.In this context, X-rays are the most appropriate method and the cornerstone of the initial approach to shoulder trauma, and at least 3 views are recommended: true anteroposterior view (AP), axial or axillary projection or modified axial projection (Velpeau view), and lateral scapula shoulder or Y view. However, patient positioning is often problematic due to the additional pain associated with limb mobilization in order to achieve the proper position for radiographic projection.The following is the description of a technique for performing an axial shoulder projection that is free of these complications, easy to standardize, and applicable to any traumatic or degenerative disease of the proximal humerus or glenohumeral joint, which, to the best of the authors’ knowledge, has not been previously published.

Brodie’s Abscess of the Proximal Humerus Metaphysis: A Case Report

Introduction:Primary subacute pyogenic osteomyelitis, or Brodie’s abscess was initially documented by Sir Benjamin Brodie in 1832. We present a case report with a 6-months follow-up period, demonstrating the successful diagnosis and surgical treatment of a focal lesion of the proximal metaphysis of the right humerus in a 21-years-old female. The pathology of hematologic osteomyelitis and its role in the development of a subacute abscess along with a review of literature and an in detail description of the pathogenesis of Brodie’s abscess is discussed and submitted.Case Presentation:A 21- years -old healthy female with a history of fall sustaining injury to the right shoulder one 1 year back followed by which she presented to the outpatient clinic with a swelling over her right shoulder. The patient was managed conservatively with analgesics and was relieved of pain over a course of one 1 week of medications, the patient now presents with pain and swelling in the right shoulder joint on and off since the episode of fall one 1 year back, which had increased over a period of past one 1 week. A week before the most recent presentation she started experiencing some discomfort and pain in her right shoulder. No recent trauma was reported. A mild swelling appeared over the proximal part of the humerus. There were no constitutional symptoms of fever or any illness reported. On examination, there was noted a painful restriction of ROM at the right shoulder joint with no rotator cuff injury. Laboratory investigations were suggestive of raised inflammatory markers. Radiograph of the right shoulder taken in the true antero-posterior view with the shoulder in the neutral rotation was suggestive of an oval lucency with surrounding sclerosis in the proximal metaphyseal region of the humerus. Magnetic resonance imaging MRI of the right shoulder joint showed features consistent with Brodie’s abscess in the proximal metaphyseal region of the humerus. Surgical debridement of the abscess was planned. The right shoulder of the patient was immobilized by a universal shoulder immobilizer for 3 days post -operatively and then Pphysiotherapy for shoulder range of movements was started. Infectious parameters decreased and there were no complications in the postoperative period. Regular follow follow-up for two 2 weeks showed clinical improvement. At 6 months follow- up, the patient had made full recovery with radiographic improvement.Conclusion :Brodie’s abscess was first described by Sir Benjamin Brodie in 1832. Primary hematogenous subacute osteomyelitis is rarely seen in the proximal metaphysis of the humerus. With appropriate surgical debridement and aggressive antibiotic cover, a near 100% success rate is observed in the treatment of Brodie’s abscess with no residual deformities in the affected bones or restrictions in the range of movements in the neighboring joints.

Implication of bone morphology in degenerative rotator cuff lesions: A prospective comparative study between greater tuberosity angle and critical shoulder angle

BackgroundDegenerative rotator cuff tear is a frequent and multifactorial pathology. The role of bone morphology of the greater tuberosity and lateral acromion has been validated, and can be measured with two plain radiographic markers on true anteroposterior views: the greater tuberosity angle (GTA) and the critical shoulder angle (CSA). However, the interdependence of both markers remains unknown, as well as their relationship with the level of professional and sports activities involving the shoulder. The aim of this prospective comparative study was to describe the correlation between the GTA and CSA in patients with degenerative rotator cuff tears. HypothesisGTA and CSA are independent factors from one another and from demographic factors, such as age, dominance, sports, or professional activities. Patient and methodsAll patients presenting to a shoulder specialized clinic were assigned to two groups. The first consisted of patients with a symptomatic degenerative rotator cuff tear visible on MRI and the control group consisted of patients with any other shoulder complaints and no history or visible imaging of any rotator cuff lesion. ResultsThere were 51 shoulders in 49 patients in the rotator cuff tear group (RCT) and 53 shoulders in 50 patients in the control group. Patient demographics were similar in both groups. Mean GTA was 72.1°±3.7 (71.0–73.1) in the RCT group and 64.0°±3.3 (63.1–64.9) in the control group (p<0.001). Mean CSA was 36.7°±3.7 (35.7–37.8) in the RCT group, and 32.1°±3.7 (31.1–33.1) in the control group (p<0.001). A summation of GTA and CSA values over 103° increased the odds of having a rotator cuff tear by 97-fold (p<0.001). There was no correlation between GTA and CSA, nor between GTA or CSA and age, sex, tear size, or dominance. Patients with different levels of professional and sports activities did not have significantly different GTA or CSA values. ConclusionGTA and CSA are independent radiologic markers that can reliably predict the presence of a degenerative rotator cuff tear. A sum of both values over 103° increases the odds of having a rotator cuff tear by 97-fold. These markers are not correlated with patient demographic or environmental factors, suggesting that the variability of the native acromion and greater tuberosity morphology may be individual risk factors for rotator cuff tear. Level of evidenceII; diagnostic study.

3D-surface scan based validated new measurement technique of femoral joint line reconstruction in total knee arthroplasty

PurposeThis study aimed to validate a new joint line measurement technique in total knee arthroplasty for separated assessment of the medial and lateral femoral joint line alteration with 3D-surface scan technology. Separate assessment of the medial and lateral joint line alteration may improve TKA alignment assessment regarding to joint line restoration in kinematic alignment and use of robotic-assisted TKA surgery.MethodsThe medial and lateral joint line difference after TKA implantation on an artificial bone model was analyzed and compared with a 3D-scan and full femoral radiographs pre- and postoperatively. Radiographic analysis included the perpendicular distance between the most distal point of the medial and lateral condyle and the reproduced preoperative lateral distal femoral angle (LDFA). For evaluation of validity and reliability, radiographs were captured initially with true anteroposterior view and subsequently with combined flexion and rotation malpositioning. Reliability of the introduced measurement technique in between three observers was tested with intraclass correlation coefficient (ICC).ResultsRadiographic measurement showed a mean difference of 0.9 mm on the medial side and 0.6 mm on the lateral side when compared to the 3D-surface scan measurement. The reliability of measurement accuracy was ≤ 1 mm in x-rays with < 10° flexion error regardless to malrotation in these images. The ICC test showed very good reliability for the medial joint line evaluation and good reliability for lateral joint line evaluation (ICC 0.92, ICC 0.86 respectively).ConclusionThe new introduced joint line measurement method showed a sufficient reliability, accuracy and precision. It provides separated information about medial and lateral joint line alteration in TKA surgery in absolute values.Level of evidenceV - Experimental Study

True Mechanical Alignment is Found Only on Full-Limb and not on Standard Anteroposterior Radiographs

PurposeThe purpose of this study was to compare alignment measured on standard anteroposterior (AP) radiographs versus full-length weight-bearing radiographs.MethodsPatients were prospectively enrolled from June 2019 to August 2019 from a single orthopedic surgeon’s practice if they were ≥ 18 years of age, obtained both AP and full-length alignment radiographs and were capable of full weight-bearing with appropriate positioning. Patients were excluded if they were < 18 years of age, had previous knee arthroplasty, previous knee or hip osteotomy, were unable to bear full weight on both limbs, and if the patient’s body habitus precluded appropriate visualization of necessary landmarks on the radiographs. Tibiofemoral angles were measured on AP radiographs using 2 techniques (AP angles 1 and 2). Linear regression and paired t tests were used to compare measurements. The minimal clinically important difference was defined as < 2°.ResultsThere were 120 patients (62 males, 58 females) with an average age of 45 ± 17 years who were enrolled. There were positive correlations between average alignment on full-length weight-bearing and AP radiographs for AP angle 1 (r = 0.72) and AP angle 2 (r = 0.76) measurement techniques (P < .001). There was a significant difference in mean alignment between full-length weight-bearing and AP measurements (AP angle 1: 2.5° difference; AP angle 2: 4.4° difference; P < .001). Frequency distributions for the minimal clinically important difference between true mechanical alignment and AP views demonstrated that 46.7% of patients had ≥ 2° difference for AP angle 1, and 78.3% of patients had ≥ 2° difference for AP angle 2.ConclusionThe average absolute difference in alignment measured between standard AP radiograph and full-length weight-bearing radiograph views was significant, with 46.7% to 78.3% of patients having a greater than 2° absolute difference between these 2 views. In cases where precise objective alignment measurement is necessary, full-length weight-bearing radiographs are recommended over standard AP radiographs for presurgical planning so as to reduce potential error in over- or underestimation of the true mechanical alignment.Study DesignProspective case-comparison; Level of evidence, 1.

Machine learning–based identification of hip arthroplasty designs

BackgroundThe purposes of this study were to develop a machine learning–based implant recognition program and to verify its accuracy. MethodsPostoperative anteroposterior (AP) X-rays (≥300 dpi) were collected of patients who underwent total hip arthroplasty. X-rays with a wire or plate added and those without a true anteroposterior view were excluded. A total of 170 X-ray images of hip implants from 29 brands were collected from five hospitals and a Google image search. These collected images were manually reorganised to ensure appropriate labelling. Collected images were preprocessed to have grey-scaled pixels with histogram equalisation for efficient training. Images varied by +10/−10°, and 3606 unique images derived from the original 170 images were created for training. Discussion of the validation set being derived 25% of training set. The recognition model structure consisted of two steps: object detection and clustering. Model training was performed with Keras deep learning platform. ResultsThe 170 X-ray images of hip implants were used to build a stem detection model using YOLOv3. Manually labelled images were successfully trained into the stem detection model. Evaluation of 58 newly labelled X-ray images showed highly accurate stem detection (mean average precision > 0.99). Fully connected layers generated 29 class outputs. After training, a receiver operating characteristic curve was generated with a test set containing 25% of all stem-cropped images, yielding an area under the curve of 0.99. ConclusionFemoral stem identification in patients with total hip arthroplasty was very accurate. This technology could be used to collect large-scale implant information. The translational potential of this articleThis program has the following clinical relevance. First, we can prepare the implants needed for revision surgery by identifying the old types of implants. Second, it can be used to diagnose peripheral osteolysis or periprosthetic fracture by further developing the ability to sensitise implant detection. Third, an automated implant detection system will help organise imaging data systematically and easily for arthroplasty registry construction.

TL 18167 - Reproducibility assessment of the Lauge-Hansen, Danis-Weber and AO classifications of ankle fractures

Introduction: Although there are some studies on the reproducibility of various classifications of ankle fractures, they are controversial and lack consensus on which classification is the most appropriate. Thus, the objective of this study is to identify which of the 3 main ankle fracture classifications has the highest intra- and interobserver reproducibility and to assess whether the medical training stage of the participants affects the evaluation. Methods: Radiographs of 30 patients with ankle fracture in anteroposterior (AP), profile and true AP views were selected. All images were evaluated by 11 participants at different stages of their medical training (5 residents and 6 orthopedic surgeons) and at 2 different times. Intra- and interobserver agreement was analyzed using the weighted Cohen's kappa coefficient. Paired Student's t-tests were performed to assess whether the degree of interobserver agreement significantly differed between classification methods. Results: The results showed significant agreement in all classifications when analyzing intraobserver agreement alone. The Danis-Weber classification showed a highly significant (p&lt;0.0001) moderate-to-excellent interobserver agreement. The Danis-Weber classification had, on average, a significantly higher degree of agreement than the other classification methods (p&lt;0.0001). Conclusion: The Danis-Weber classification had the highest reproducibility among the classification methods evaluated in this study.

Learning Curves in the Arthroscopic Latarjet Procedure: A Multicenter Analysis of the First 25 Cases of 5 International Surgeons

To analyze the learning curves of 5 experienced, fellowship-trained shoulder surgeons and their respective 25 first arthroscopic Latarjet cases in regard to surgical time, graft placement, complication rates, and recurrent instability. The first 25 arthroscopic Latarjet procedures of 5 surgeons were retrospectively analyzed in an international multicenter setting, and thus 125 patients were included in this study. The surgical time, intraoperative and postoperative events out of the ordinary, and graft positioning were examined. The 125 patients consisted of 16 women (12.8%) and 109 men (87.2%). In 81.6% (n= 102), surgery was undertaken as a first-line procedure, whereas 18.4% (n= 23) were revisions. Surgical time decreased significantly from an average of 123.8minutes (range 70 to 210) to 92.6minutes (range 50 to 160) from the first 5 cases to the last 5 cases of each surgeon within a period of <2years. Overall, 22 events in 21 patients requiring additional treatment were reported (17.6%). Five (4%) were unlikely to affect final outcome and did not require revision surgery. Twelve (9.6%) required revision surgery that was not trauma related yet was prone to affect outcomes. Five events were trauma-related (4%), 4 requiring revision surgery and 1 treated conservatively. Overall, 6 patients (4.8%) had recurrent shoulder instability, 3 as a result of a traumatic event. Conventional radiology showed the bone-block in ideal positioning in 93 cases (74.4%), flush with the glenoid in a true anteroposterior view. In 3 cases (2.4%), it was considered too high, 15 too low (12%), 5 too lateral (4%), and 15 too medial (12%). Some patients had combinations of the above. This analysis shows that surgical time in arthroscopic Latarjet can be significantly reduced after only 20 cases. However, complication rates did not decrease over this time. The authors believe that the arthroscopic Latarjet is a challenging yet viable technique to treat anterior shoulder instability, achieving results equal to the open technique with advantages of the arthroscopic setting. Level IV, retrospective cohort study.

Syndesmosis assessment in postoperative patients subjected to surgical treatment of supra-syndesmotic fracture

Objective: To demonstrate the patterns of syndesmosis reconstruction in ankle fractures via the measurement of pre-established and universally accepted parameters. Methods: In a retrospective study, fractures with radiographic images obtained during the postoperative period showing fixation of the distal tibiofibular syndesmosis were selected. After this selection, fracture reduction and syndesmosis fixation were evaluated by measuring radiographic parameters in the selected cases. Results: Twenty-three patients (63.8%) were male. Fourteen fractures (38.8%) were operated on by a senior surgeon (foot and ankle specialist). All syndesmoses were fixed with only 1 screw, and 35 patients (97.2%) had syndesmosis fixation involving 3 cortices. The mean syndesmosis fixation height from the articular surface was 2.20cm. Four fractures (11.1%) presented radiographic signs of medial ligament reconstruction. Regarding measurement of the tibiofibular space, in the anteroposterior (AP) view, 33 patients (91.6%) had values within the normal range. Regarding the tibiofibular overlap, in the AP view, 19 patients (52.7%) had measurements with values greater than 10mm (normal). In the evaluation of tibiofibular overlap, in the true AP view, all patients (100%) presented measurements greater than 1mm (normal). Regarding the measurement of the talocrural angle, only 1 patient did not have normal parameters. Regarding the medial clear space, only 2 patients (5.5%) had values above normal during the postoperative period. Conclusion: The adoption of objective parameters, in a standardized manner and relative to the contralateral side, adds additional value to the evaluation and ensures an accessible and reproducible method for the evaluation of these injuries. Level of Evidence II; Prognostics Studies; Retrospective Study.

Progressive glenoid bone loss caused by erosion in humeral head resurfacing.

Cementless surface replacement of the shoulder represents an alternative to conventional stemmed anatomic prostheses. Glenoid erosion is awell-known complication in hemiarthroplasty. However, there is limited data concerning radiographic evaluation and prognostic factors for this phenomenon. The aim of our study was to determine the development of glenoid erosion following shoulder resurfacing using anew measurement technique and detect potential prognostic factors. We performed aretrospective analysis on 38shoulders undergoing humeral head resurfacing with amean follow-up of 65.4± 43months. Clinical and radiographic evaluation followed astandardized protocol including pre- and postoperative Constant score, active range of motion, and X‑rays in true anteroposterior view. Three independent observers performed measurements of glenoid erosion. We found good interobserver reliability for glenoid erosion measurements (intraclass correlation coefficient [ICC] 0.74-0.78). Progressive glenoid erosion was present in all cases, averaging 5.5± 3.9 mm at more than 5years' follow-up. Male patients demonstrated increased glenoid bone loss within the first 5years (p< 0.04). The mean Constant score improved to 55.4± 23.6 points at the latest follow-up. Younger age was correlated to increased functional outcome. Revision rate due to painful glenoid erosion was 37%. Glenoid erosion can be routinely expected in patients undergoing humeral head resurfacing. Painful glenoid erosion leads to deterioration in functional outcome and necessitates revision surgery in ahigh percentage of cases.

The Corona Dentis: Description of an Anatomic Variant with Technical Implications for Anterior Odontoid Screw Placement.

Type 2 odontoid fractures are the most common cervical fractures among the elderly. Neurologic deficit is usually caused by myelopathy as a result of posterior dens migration. Direct anterior screw placement provides stabilization and can preserve C1-C2 movement. The presence of a bony excrescence on the anterior superior tip of the dens may lead to placement of a screw of incorrect length. Twenty C2 dry specimens were examined for the presence of a corona dentis, which is a bony excrescence in the coronal plane near the apex of the dens. When identified, measurements of the corona dentis were performed using calipers and a ruler. In addition, anteroposterior (AP) and lateral fluoroscopy was performed on all specimens found to have a corona dentis. A corona dentis was found on 20% of our C2 specimens and had an average width of 9 mm and an average height of 4.5 mm. The average width of the dens did not vary as the normal tip of the dens transitioned into the coronae. In no specimen did the corona dentis seem to be composed of trabecular bone and it was seen as a superior projection of cortical bone on fluoroscopy. On fluoroscopy, the corona dentis could be identified on a true AP projection. In angulated AP views, fluoroscopic images overestimated the length of the corona dentis. We describe a new entity termed the corona dentis because of its crownlike feature. It is a superior cortical bone protrusion and should be noted as a variant of the dens during anterior odontoid screw placement. Its propensity to increase the height of the dens markedly can lead to higher rates of neurologic deficits during type 2 odontoid fractures if not appreciated. A true AP view is critical for correct screw size placement.

True anteroposterior view pedicle screw insertion technique

BackgroundThe wide use of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) surgery in the treatment of degenerative disc disease of lumbar spine in spinal surgery highlights the gradual decrease in the use of traditional pedicle screw insertion technology. This study aims to analyze the accuracy of the true anteroposterior view pedicle screw insertion technique in MIS-TLIF surgery, compare it with conventional pedicle screw insertion technology, and discuss its clinical application value.MethodsFifty-two patients undergoing true anteroposterior view (group A) and 87 patients undergoing conventional pedicle screw insertion (group B) were diagnosed with lumbar disc herniation or lumbar spinal stenosis. Time for screw placement, intraoperative irradiation exposure, accuracy rate of pedicle screw insertion, and incidence of neurovascular injury were compared between the two groups.ResultsThe time for screw placement and intraoperative irradiation exposure was significantly less in group A. Penetration rates of the paries lateralis of vertebral pedicle, medial wall of vertebral pedicle, and anterior vertebral wall were 1.44%, 0%, and 2.40%, respectively, all of which were significantly lower than that in group B. No additional serious complications caused by the placement of screw were observed during the follow-up period in patients in group A, but two patients with medial penetration underwent revision for unbearable radicular pain.ConclusionThe application of true anteroposterior view pedicle screw insertion technique in MIS-TLIF surgery shortens time for screw placement and reduces the intraoperative irradiation exposure along with a higher accuracy rate of screw placement, which makes it a safe, accurate, and efficient technique.

The influence of radiographic viewing perspective and demographics on the critical shoulder angle

Accurate assessment of the critical shoulder angle (CSA) is important in clinical evaluation of degenerative rotator cuff tears. This study analyzed the influence of radiographic viewing perspective on the CSA, developed a classification system to identify malpositioned radiographs, and assessed the relationship between the CSA and demographic factors. Glenoid height, width, and retroversion were measured on 3-dimensional computed tomography reconstructions of 68 cadaver scapulae. A digitally reconstructed radiograph was aligned perpendicular to the scapular plane, and retroversion was corrected to obtain a true anteroposterior (AP) view. In 10 scapulae, incremental anteversion/retroversion and flexion/extension views were generated. The CSA was measured, and a clinically applicable classification system was developed to detect views with >2° change in CSA vs. true AP view. The average CSA was 33° ± 4°. Intraobserver and interobserver reliability was high (intraclass correlation coefficient ≥ 0.81) but decreased with increasing viewing angle. Views beyond 5° anteversion, 8° retroversion, 15° flexion, and 26° extension resulted in >2° deviation of the CSA compared with the true AP view. The classification system was capable of detecting aberrant viewing perspectives with sensitivity of 95% and specificity of 53%. Correlations between glenoid size and CSA were small (R ≤ 0.3), and CSA did not vary by gender (P = .426) or side (P = .821). The CSA was most susceptible to malposition in anteversion/retroversion. Deviations as little as 5° in anteversion resulted in a CSA >2° from true AP view. A new classification system refines the ability to collect true AP radiographs of the scapula. The CSA was unaffected by demographic factors.