Accuracy and Reliability of a Simple Calculation for Measuring Glenoid Bone Loss on 3-Dimensional Computed Tomography Scans

Functional Anatomy and Biomechanics of Shoulder Instability

The glenohumeral joint is the least congruent and least constrained joint with a complex relationship of static and dynamic stabilizers to balance its native mobility with functional stability. In the young athlete, anterior shoulder instability is multifactorial and can be a challenge to treat, requiring a patient-specific treatment approach. Surgical decision-making must consider patient-specific factors such as age, sport activity and level, underlying ligamentous laxity, and goals for return to activity, in addition to careful scrutiny of the underlying pathology to include humeral and glenoid bone loss and surrounding scapular bone morphology.

Artificial intelligence in shoulder and elbow surgery: overview of current and future applications

Artificial intelligence (AI) is amongst the most rapidly growing technologies in orthopedic surgery. With the exponential growth in healthcare data, computing power, and complex predictive algorithms, this technology is poised to aid providers in data processing and clinical decision support throughout the continuum of orthopedic care. Understanding the utility and limitations of this technology is vital to practicing orthopedic surgeons, as these applications will become more common place in everyday practice. AI has already demonstrated its utility in shoulder and elbow surgery for imaging-based diagnosis, predictive modeling of clinical outcomes, implant identification, and automated image segmentation. The future integration of AI and robotic surgery represents the largest potential application of AI in shoulder and elbow surgery with the potential for significant clinical and financial impact. This editorial's purpose is to summarize common AI terms, provide a framework to understand and interpret AI model results, and discuss current applications and future directions within shoulder and elbow surgery.

Objective calculation of glenoid bone loss in anterior shoulder instability based on the contour of the posteroinferior quadrant using the best-fit circle method: an accurate and reproducible evaluation

BACKGROUND

Glenoid bone loss is proposed to be an important risk factor for recurrent anterior shoulder instability. The purpose of the present study was to develop an accurate and reproducible method for quantifying a bone loss in patients with anterior shoulder instability.

METHODS

A total of 66 sets of computed tomography images of the glenoid were acquired and en face view was established. Based on the contour of the inferior half and posteroinferior quadrant of the glenoid, the best-fit circle was drawn using the least-squares method with a comparison of the radii. A bone loss was created via a simulated osteotomy, and a method for estimating the bone loss based on the contour of the posteroinferior quadrant was developed.

RESULTS

The radii of the best-fit circle were 29.30 ± 1.84 mm and 33.76 ± 2.04 mm, based on the inferior half and posteroinferior quadrant of the glenoid, respectively (P < .01). Bone loss quantification using the contour of the inferior half or posteroinferior quadrant with simulated osteotomy showed a significant difference (P < .01). For a 25% of glenoid bone loss, the estimated value using the traditional method on the contour of the posteroinferior quadrant was 34%. A new method for accurate bone loss quantification was developed based on the contour of the posteroinferior quadrant of the glenoid.

CONCLUSION

Estimation of the glenoid bone loss based on the rim of the posteroinferior quadrant may overestimate the glenoid bone loss due to the difference in the radius of the curvature of the inferior half and posteroinferior quadrant. A mathematical method developed to correct this error and may aid in more accurately, measuring the glenoid bone loss using the contour of the posteroinferior quadrant in patients with anterior shoulder instability.

Glenoid Bone Loss in Recurrent Shoulder Instability After Arthroscopic Bankart Repair: A Systematic Review

BACKGROUND

Glenoid bone loss has been reported to occur in as many as 86% of patients with recurrent shoulder stability. This systematic review evaluated the amount of glenoid bone loss associated with recurrent shoulder dislocation or subluxation and with worse patient-reported outcomes after arthroscopic Bankart repair. We hypothesized that the percentage of glenoid bone loss associated with recurrent instability after arthroscopic Bankart repair is lower than the previously proposed critical value of 25%.

METHODS

The systematic review included 528 patients with glenoid bone loss from 3 clinical studies. The percentage of bone loss was the value quantified and reported in each study. Failure was defined as recurrent dislocation or subluxation. The percentage of glenoid bone loss associated with recurrent shoulder dislocation or subluxation after arthroscopic Bankart labral repair was analyzed with receiver operating characteristic (ROC) curve analysis.

RESULTS

Recurrent dislocation or subluxation occurred in 23.7% (125) of 528 patients in the pooled study cohort. There was a significant difference in age between those in whom the arthroscopic Bankart repair failed and those in whom it did not (22.9 versus 24.3 years; p = 0.009). The ROC curve analysis demonstrated that ≥16.0% glenoid bone loss was predictive of recurrent shoulder dislocation or subluxation (Youden index = 0.59, sensitivity = 80%, specificity = 80%). In patients who did not sustain a recurrent dislocation or subluxation, the ROC curve analysis demonstrated that 20.0% glenoid bone loss was predictive of a Single Assessment Numeric Evaluation (SANE) score of <85% (Youden index = 0.93, sensitivity = 93%, specificity = 100%).

CONCLUSIONS

The critical amount of glenoid bone loss associated with an increased risk of persistent instability was found to be less than previously reported. Glenoid bone loss of ≥16.0% was found to place patients at higher risk for recurrent shoulder dislocation or subluxation after treatment with arthroscopic Bankart repair alone.

LEVEL OF EVIDENCE

Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Degree of articular injury as measured by CT cross sectional area is associated with physical function following the treatment of bicondylar tibial plateau fractures

BACKGROUND

Bicondylar tibial plateau fractures are complex injuries that commonly require surgical repair. Long-term clinical outcome has been associated with discrepancies in leg alignment, instability and condylar width abnormalities. While intuitive, the degree of articular damage at time of injury has not been linked to outcomes in patients with bicondylar tibial plateau fractures. The aim of this study was to quantify percentage of articular surface cross sectional area disruption and assess for correlation between the degree of articular injury and patient reported physical function.

METHODS

Retrospective cohort study at two level 1 trauma centers. 57 consecutive patients undergoing surgical repair for bicondylar tibial plateau fractures between 2013 and 2016.

MAIN OUTCOME MEASURE

Preoperative CT scans were reviewed, and the percentage of articular surface disruption cross sectional area was calculated. PROMIS® scores were collected from patients at a minimum of 2 years.

RESULTS

57 patients with an average age of 58 ± 14.3 years were included. The average PROMIS® score was 45.5. There was a correlation between percentage of articular surface disruption and total PROMIS® scores (0.4, CI: 0.2-0.5, p = .007) and the physical function of the PROMIS® score (0.4, CI: 0.2-0.6, p < .001).

CONCLUSION

Our method for calculating articular surface disruption on CT is a simple, reproducible and accurate method for assessing the degree of articular damage in patients with bicondylar tibial plateau fractures. We found that the percentage of cross-sectional articular surface disruption correlates with patient reported outcomes and physical function.

Glenoid Track Assessment at Imaging in Anterior Shoulder Instability: Rationale and Step-by-Step Guide

Anterior shoulder dislocation is the most common form of joint instability in humans, usually resulting in soft-tissue injury to the glenohumeral capsuloligamentous and labral structures. Bipolar bone lesions in the form of fractures of the anterior glenoid rim and posterolateral humeral head are often associated with anterior shoulder dislocation and can be a cause or result of recurrent dislocations. Glenoid track assessment is an evolving concept that incorporates the pathomechanics of anterior shoulder instability into its management. Currently widely endorsed by orthopedic surgeons, this concept has ramifications for prognostication, treatment planning, and outcome assessment of anterior shoulder dislocation. The glenoid track is the contact zone between the humeral head and glenoid during shoulder motion from the neutral position to abduction and external rotation. Two key determinants of on-track or off-track status of a Hill-Sachs lesion (HSL) are the glenoid track width (GTW) and Hill-Sachs interval (HSI). If the GTW is less than the HSI, an HSL is off track. If the GTW is greater than the HSI, an HSL is on track. The authors focus on the rationale behind the glenoid track concept and explain stepwise assessment of the glenoid track at CT or MRI. Off-track to on-track conversion is a primary goal in stabilizing the shoulder with anterior instability. The key role that imaging plays in glenoid track assessment warrants radiologists' recognition of this concept along with its challenges and pitfalls and the production of relevant and actionable radiology reports for orthopedic surgeons-to the ultimate benefit of patients. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

CT methods for measuring glenoid bone loss are inaccurate, and not reproducible or interchangeable

Aims

Glenoid bone loss is a significant problem in the management of shoulder instability. The threshold at which the bone loss is considered "critical" requiring bony reconstruction has steadily dropped and is now approximately 15%. This necessitates accurate measurement in order that the correct operation is performed. CT scanning is the most commonly used modality and there are a number of techniques described to measure the bone loss however few have been validated. The aim of this study was to assess the accuracy of the most commonly used techniques for measuring glenoid bone loss on CT.

Methods

Anatomically accurate models with known glenoid diameter and degree of bone loss were used to determine the mathematical and statistical accuracy of six of the most commonly described techniques (relative diameter, linear ipsilateral circle of best fit (COBF), linear contralateral COBF, Pico, Sugaya, and circle line methods). The models were prepared at 13.8%, 17.6%, and 22.9% bone loss. Sequential CT scans were taken and randomized. Blinded reviewers made repeated measurements using the different techniques with a threshold for theoretical bone grafting set at 15%.

Results

At 13.8%, only the Pico technique measured under the threshold. At 17.6% and 22.9% bone loss all techniques measured above the threshold. The Pico technique was 97.1% accurate, but had a high false-negative rate and poor sensitivity underestimating the need for grafting. The Sugaya technique had 100% specificity but 25% of the measurements were incorrectly above the threshold. A contralateral COBF underestimates the area by 16% and the diameter by 5 to 7%.

Conclusion

No one method stands out as being truly accurate and clinicians need to be aware of the limitations of their chosen technique. They are not interchangeable, and caution must be used when reading the literature as comparisons are not reliable.

Surgical treatment of shoulder instability in active-duty service members with subcritical glenoid bone loss: Bankart vs. Latarjet

INTRODUCTION

Subcritical bone loss has been identified as a risk factor for potentially inferior outcomes following typical arthroscopic soft tissue repair. One alternative that has been presented as an option for patients with bone loss is the Latarjet, an ipsilateral coracoid transfer to the anteroinferior glenoid. The purpose of this study is to compare the outcomes between the arthroscopic Bankart repair and the open Latarjet for the treatment of anterior shoulder instability in patients with subcritical bone loss. We hypothesize that the open Latarjet will provide higher patient-reported outcome measure scores and lower rates of dislocation.

METHODS

A retrospective cohort comparison of patients with anterior glenohumeral instability procedures was performed. Inclusion criteria included symptomatic anterior shoulder instability, subcritical glenoid bone loss (13.5%-24%), surgical treatment with arthroscopic Bankart repair or open Latarjet, and minimum follow-up of 2 years. Outcomes included recurrent instability (defined as postoperative dislocation or subjective subluxation), permanent physical restrictions, Western Ontario Shoulder Index (WOSI), and Single Assessment Numeric Evaluation (SANE) scores.

RESULTS

Forty-seven patients were included, 25 of whom underwent an arthroscopic Bankart repair and 23 patients an open Latarjet. The average bone loss was 17.8% and 19.3%, respectively. Overall, 8 patients experienced recurrent instability, 6 in the arthroscopic Bankart group and 2 in the open Latarjet group (P = .162). The average postoperative SANE score for arthroscopic Bankart group was 48% and for the open Latarjet group, 84% (P < .001). The average postoperative WOSI score for the arthroscopic Bankart group was 53.6% and for the open Latarjet group, 67.9% (P = .069). There were significantly more patients placed on permanent physical restrictions in the arthroscopic Bankart repair group (16) compared with open Latarjet (3) (P < .001).

CONCLUSION

In patients with subcritical glenoid bone loss (defined as 13.5%-24%), patients treated with an open Latarjet have insignificantly higher SANE and WOSI scores and lower permanent physical restrictions than patients treated with an arthroscopic Bankart repair. We found no statistically significant difference in recurrent instability rates between the open Latarjet and arthroscopic Bankart repair (P = .162).

Editorial Commentary: Shoulder Remplissage Is a Beneficial Addition to Bankart or Glenoid Bone Loss Treatment: Stay on Track and Use Wisely

In patients with on-track shoulder Hill-Sachs lesions, the addition of remplissage using a double-pulley technique to Bankart repair improves outcomes including residual apprehension and without loss of external rotation. A caveat is that measurement of both the Hill-Sachs lesion and glenoid bone loss may be inconsistent. A second caveat is that determination of the glenoid track can be affected by scapular positioning. Not all "on-track" lesions are alike. In terms of outcome assessment, apprehension has up to 95% specificity for anterior shoulder instability and is a key finding in determining the results of shoulder stabilization. Recurrent instability may not be as sensitive of an outcome measure, because patients will avoid positions of apprehension. Finally, remplissage should be used cautiously in peripheral track lesions. For smaller Hill-Sachs lesions, remplissage can provide extraordinary success, and for larger lesions that are close to engaging, glenoid bone loss must also be treated, especially in a younger, active patient.

Patella-Posterior Turning Point of the Distal Femur Distance Is a Potential Indicator for Diagnosing Patella Alta in Recurrent Patellar Dislocation Population

PURPOSE

To introduce a simple patellar height measurement method (patella-posterior turning point of the distal femur [P-PTP] Distance) independent of patellar anatomy with standardized patient position, and tested the reliability, validity, and diagnostic accuracy compared with commonly used ratios in knee extension.

METHODS

We retrospectively reviewed 418 computed tomography (CT) images of the knee joint in a group of patients who were diagnosed recurrent patellar dislocation (RPD). With the three-dimensional (3D) CT reconstructed knee, patellar height was qualitatively assessed by the patellar engagement with the femoral trochlea in terminal knee extension to divide RPD population into case (patella alta) and control group. With digitally reconstructed lateral radiographs, patellar height was measured with P-PTP distance (perpendicular distances between the distal edge of patella articular surface and posterior turning point of distal femur), and four commonly used ratios: Caton-Deschamps index, Modified Insall-Salvati index, Blackburne-Peel index, and Insall-Salvati index. An unpaired t-test was conducted to determine significant differences between groups. Correlation coefficient, intra- and inter-observer reliability, receiver operating characteristic (ROC) curves and the area under the ROC curve (AUC) were also calculated.

RESULTS

198 knee images (198 patients) were included for final evaluation. Patella alta was present in 72 knees (36.3%) with RPD. The effect size was relatively large between the case and control group for P-PTP distance (d = -1.619; 95% CI, -1.948 to -1.286). P-PTP distance correlated moderately to strongly with four commonly used ratios (P < .001). Intraobserver and interobserver reliability was good for P-PTP distance. The AUC of the ROC curve was categorized as excellent for P-PTP distance, better than other measurements (P < .001), and the cutoff value was 4.2 mm with the highest sensitivity (86.11%) and specificity (84.92%).

CONCLUSIONS

The measurement method, P-PTP distance, showed good intra-observer and inter-observer reliability, well correlated with commonly used ratios, and presented best diagnostic accuracy among commonly used ratios for predicting RPD. P-PTP distance might be a potential indicator for identifying patella alta in RPD patients when supine and knee extended.

CLINICAL RELEVANCE

The measurement reported in this study may help in advancing clinical evaluation of patella alta, providing an alternative and simple method to measure patellar height. Standing or weight-bearing plain lateral radiographs obtained from the routine practice should be further assessed in the next step to further validate the method.

Area Measurement Percentile of 3-Dimensional Computed Tomography Has the Highest Interobserver Reliability When Measuring Anterior Glenoid Bone Loss

PURPOSE

To determine the accuracy of glenoid bone loss measurement and the difference between 3 methods of measurement, as well as the measurements application to previously published studies.

METHODS

A list of patients with anterior bony glenoid defects was created through a search of electronic medical records. Three surgeons reviewed each patient's advanced imaging (computed tomography [CT], 3-dimensional [3D] CT, or magnetic resonance imaging), and glenoid bone loss was measured by 3 different methods: (1) linear measurement percentile (LMP), (2) area measurement percentile (AMP), and (3) circle-line method (CLM). The intraclass correlation coefficients between reviewers and mathematical differences between measurement techniques were calculated.

RESULTS

The images of 125 patients with anterior glenoid bone loss were measured. For all imaging studies, the intraclass correlation coefficient was greatest with the AMP (0.738) and CT with 3D reconstruction (0.735). Within the entire sample, average bone loss measured 21.3% (range, 5.6%-43.5%) by the LMP method, 15.7% (range, 1.6%-42.2%) by the CLM, and 16.5% (range, 2.3%-40.3%) by the AMP method. On average, the difference between the LMP and AMP methods was 4.8%. When the AMP and LMP methods were compared, the greatest difference in measurement was 5.9%, and this occurred at an LMP of 19.1%, which was an AMP of 13.2%.

CONCLUSIONS

When measuring anterior glenoid bone loss, CT with 3D reconstruction and the AMP method have the greatest interobserver reliability. Furthermore, the greatest difference between the LMP and AMP methods occurs at an LMP between 18.3% and 20.0% and an AMP between 12.4% and 14.2%, with the difference ranging from 5.7% to 5.9%.

CLINICAL RELEVANCE

When measuring anterior glenoid bone loss, evaluation of CT with 3D reconstruction is more reliable than magnetic resonance imaging evaluation. Furthermore, the AMP method has the greatest interobserver reliability when compared with the LMP method and CLM.

Glenoid Bone Loss Determination: Validity and Reliability of the Constellation Technique Versus the Sagittal Best Fit Circle Technique

OBJECTIVE

To propose a new method for glenoid bone loss measurement, the constellation technique (CST); determine its reliability and accuracy; and compare the validity of CST with that of the conventional technique (CVT) and standard measurements for ratio calculation.

MATERIALS AND METHODS

Sixty shoulders with intact glenoids and no glenohumeral instability and arthritis underwent CT scans. Simulated osteotomies were conducted on the 3D models of glenoids at two cutting locations, expressed as clock face times (2:30-4:20; 1:30-5:00). Two experienced surgeons compared three methods for glenoid bone loss measurement; CVT (best-fit circle), CST ('5S' steps), and standard measurement. Eight undergraduates remeasured five randomly chosen shoulders with moderate to severe bone loss. Intraclass correlation coefficients (ICCs) were calculated for raters.

RESULTS

With a defect range between 2:30 and 4:20, all 60 glenoids demonstrated minimal bone loss (< 15%); while between 1:30 and 5:00, 42 shoulders were with moderate bone loss (15-20%), and 18 shoulders with severe bone loss (≥ 20%). For experienced raters, no significant differences were noted between protocos for all categories of bone loss (p ≥ 0.051), with good inter- and intraobserver reliability indicated by ICC. For novice raters, post hoc Tukey analysis found that CST was more accurate in one patient with a standard mean bone loss of 23.2% ± 1.9% compared with CVT.

CONCLUSION

The CST turned the key step of glenoid defect evaluation from deciding an en face view to determining the glenoid inferior rim. The protocol is simple, accurate, and reproducible, especially for novice raters.

Tibial Tuberosity-Trochlear Groove Distance and Its Components in Patients with and without Episodic Patellar Dislocation: A Study of 781 Knees

BACKGROUND

The purposes of the present study were (1) to measure the tibial tuberosity-trochlear groove distance and its components with the knee in extension, (2) to determine their diagnostic performance in distinguishing between patients with and without episodic patellar dislocation, and (3) to investigate the relationship of each component to the total tibial tuberosity-trochlear groove distance.

METHODS

We retrospectively reviewed computed tomography (CT) images of the knee joint in a group of patients with episodic patellar dislocation and a group of control subjects who were treated for another type of knee disorder in our institution between 2015 and 2021. Tibial tuberosity-trochlear groove distance, tibial tubercle lateralization, trochlear groove medialization, and knee rotation were measured on axial images. Partial correlation analysis of the measured parameters was performed after adjusting for remaining variables. Receiver operating characteristic (ROC) curves and the areas under the ROC curves (AUCs) were assessed to assess the diagnostic accuracy. A subgroup analysis based on femoral trochlear dysplasia classification was also performed.

RESULTS

After screening of 653 patients (947 knees) in our hospital's patient registry, a total of 521 patients (781 knees) were analyzed, including 541 knees (69.3%) with episodic patellar dislocation and 240 knees (30.7%) without episodic patellar dislocation (control group). The tibial tuberosity-trochlear groove distance demonstrated the best diagnostic performance, with the AUC being significantly better than that for other parameters (p < 0.001). The tibial tuberosity-trochlear groove distance was moderately to strongly correlated with knee rotation and trochlear groove medialization in the control and episodic patellar dislocation groups (p < 0.001). However, tibial tubercle lateralization showed a weak correlation with the tibial tuberosity-trochlear groove distance in the control group and moderate correlation in the episodic patellar dislocation group (p < 0.001). Knees with a type-D femoral trochlea had a significantly greater tibial tuberosity-trochlear groove distance than those with a type-A, B, or C femoral trochlea (p ≤ 0.011).

CONCLUSIONS

Tibial tuberosity-trochlear groove distance, a reliable predictor of episodic patellar dislocation, was affected more by knee rotation and trochlear groove medialization and was less affected by tibial tubercle lateralization, and it increased with an increasing grade of femoral trochlear dysplasia. The correlation of the tibial tuberosity-trochlear groove distance and its components as noted in the current study will help to achieve a better understanding of the tibial tuberosity-trochlear groove distance.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Computed Tomography Imaging Analysis of the MPFL Femoral Footprint Morphology and the Saddle Sulcus: Evaluation of 1094 Knees

Background:

The medial patellofemoral ligament (MPFL) has been reported to be anatomically attached from an osseous saddle region (saddle sulcus) between neighboring landmarks on the femur, including the adductor tubercle (AT), medial epicondyle (ME), and medial gastrocnemius tubercle (MGT). However, the position and prevalence of the saddle sulcus remain unknown.

Purpose:

To study the femoral footprint of MPFL and the prevalence of the saddle sulcus with computed tomography (CT) imaging; quantify the position of the saddle sulcus; and determine the relevant factors of the identified position and measuring distances.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

A total of 1094 knees in 753 patients were studied. Knees were organized into an anterior cruciate ligament reconstruction (ACLR) group (controls) and a recurrent patellar dislocation (RPD) group. Using 3-dimensionally reconstructed CT images, the authors determined the prevalence of the saddle sulcus and its position relative to the AT, the ME, the Schöttle point (1.3 mm anterior to the distal posterior cortex and 2.5 mm distal to the posterior origin of the medial femoral condyle), and the Fujino point (approximately 10 mm distal to the AT). Analysis of covariance was used to adjust for age, sex, side, and body mass index on the measurements.

Results:

There were 555 knees in the control group and 539 knees in the RPD group. The MPFL femoral footprint presented as an oblique, oblong, osseous region (saddle sulcus) in 75.7% of knees (75.0%, ACLR group vs 76.4%, RPD group; P < .001). The saddle sulcus was located a mean of 12.2 mm (95% CI, 12.0-12.4 mm) from a line connecting the apex of the AT to the ME (AT-ME) and a mean of 7.6 mm (95% CI, 7.5-7.8 mm) posteriorly perpendicular to that line. The location as a proportion of the AT-ME distance was 63.1% (95% CI, 62.6%-63.7%) in the X direction and 39.8% (95% CI, 39.1%-40.5%) in the Y direction. The Schöttle and Fujino points lay anterior and proximal to the saddle sulcus more than 5 mm away from the center of the saddle sulcus. Women had a higher prevalence of saddle sulcus (odds ratio [OR], 1.33 [95% CI, 1.00-1.75]; P = .046) compared with men.

Conclusion:

The saddle sulcus was identified in 75.7% of knees from the medial femoral aspect, with its center located consistently between the AT and ME.

CT estimation of glenoid bone loss in anterior glenohumeral instability

Aims

Recurrent dislocation is both a cause and consequence of glenoid bone loss, and the extent of the bony defect is an indicator guiding operative intervention. Literature suggests that loss greater than 25% requires glenoid reconstruction. Measuring bone loss is controversial; studies use different methods to determine this, with no clear evidence of reproducibility. A systematic review was performed to identify existing CT-based methods of quantifying glenoid bone loss and establish their reliability and reproducibility

Methods

A Preferred Reporting Items for Systematic reviews and Meta-Analyses-compliant systematic review of conventional and grey literature was performed.

Results

A total of 25 studies were initially eligible. Following screening, nine papers were included for review. Main themes identified compared 2D and 3D imaging, as well as linear- compared with area-based techniques. Heterogenous data were acquired, and therefore no meta-analysis was performed.

Conclusion

No ideal CT-based method is demonstrated in the current literature, however evidence suggests that surface area methods are more reproducible and lead to fewer over-estimations of bone loss, provided the views used are standardized. A prospective imaging trial is required to provide a more definitive answer to this research question. Cite this article: Bone Jt Open 2022;3(2):114–122.

[Comparison of Short-term Results of Preoperative Planning Combined with Fluorescence Video-assisted Thoracoscopic Precision Segmentectomy and Traditional Thoracoscopic Segmentectomy in the Treatment of Early Lung Adenocarcinoma]

背景与目的

肺癌的死亡率居所有恶性肿瘤的第一位，但对于早期肺腺癌患者不同的肺段切除术之间手术效果及对肺功能的影响研究较少。本研究旨在评估术前规划联合荧光胸腔镜精准肺段切除术与传统肺段切除术两种手术方式对早期肺腺癌患者肺功能保留程度和近期结果比较。

方法

前瞻性选取2020年1月1日-2020年10月31日于中国科学技术大学附属第一医院胸外科行胸腔镜肺段切除术患者60例，精准组30例，传统组30例，比较两组患者临床病理特征、围手术期资料和术后肺功能情况。

结果

精准组在手术时间上较传统组更短，差异有统计学意义（P < 0.05）。术前肺功能精准组与传统组的用力肺活量（forced vital capacity, FVC）、一秒用力呼气容积（forced expiratory volume in one second, FEV₁）和一氧化碳弥散量（carbon monoxide diffusing capacity, DLCO）分别为：（3.65±0.63）L vs（3.54±0.64）L、（2.72±0.50）L vs（2.54±0.48）L及（20.36±3.02）mL/mmHg/min vs（19.16±3.18）mL/mmHg/min，差异均无统计学意义（P > 0.05）。术后1个月肺功能精准组与传统组的FVC、FEV₁和DLCO分别为：（3.35±0.63）L vs（2.89±0.57）L、（2.39±0.54）L vs（2.09±0.48）L及（17.43±3.10）mL/mmHg/min vs（15.78±2.86）mL/mmHg/min，差异均有统计学意义（P < 0.05）；术后3个月肺功能精准组与传统组的FVC和DLCO分别为：（3.47±0.63）L vs（3.20±0.56）L、（19.38±3.02）mL/mmHg/min vs（17.79±3.21）mL/mmHg/min，差异均无统计学意义（P > 0.05）。

结论

术前规划联合荧光胸腔镜精准肺段切除术在段间平面识别、解剖血管及术后恢复等方便提供了优势，明显缩短了手术时间，使治疗更为精准。

Three-Dimensional Quantification of Glenoid Bone Loss in Anterior Shoulder Instability: The Anatomic Concave Surface Area Method

Background

Recurrent shoulder instability may be associated with glenoid erosion and bone loss. Accurate quantification of bone loss significantly influences the contemplation of surgical procedure. In addition, assessment of bone loss is crucial for surgical planning and accurate graft placement during surgery.

Purpose

To quantify the concave surface area of glenoid bone loss by using 3-dimensional (3D) segmented models of the scapula and to compare this method with the best-fit circle and glenoid height/width methods, which use the glenoid rim for bone loss estimations.

Study Design

Cohort study (diagnosis); Level of evidence, 2.

Methods

A total of 36 consecutive preoperative bilateral computed tomography scans of patients eligible for a primary Latarjet procedure were selected from our institutional surgical database (mean patient age, 29 ± 9 years; 31 men and 5 women). The 3D models of both scapulae were generated using medical segmentation software and were used to map the anatomic concave surface area (ACSA) of the inferior glenoid using the diameter of the best-fit circle of the healthy glenoid. Bone loss was calculated as a ratio of the difference between surface areas of both glenoids (healthy and pathological) against the anatomic circular surface area of the healthy glenoid (the ACSA method). These results were compared with bone loss calculations using the best-fit circle and glenoid height/width methods. Inter- and intraobserver reliability were also calculated.

Results

The mean (± SD) bone loss calculated using the ACSA, the best-fit circle, and glenoid height/width methods was 9.4% ± 6.7%, 14.3% ± 6.8%, and 17.6% ± 7.3%, respectively. The ACSA method showed excellent interobserver reliability, with an intraclass correlation coefficient (ICC) of 0.95 versus those for the best-fit circle (ICC, 0.71) and glenoid height/width (ICC, 0.79) methods.

Conclusion

Quantification of instability-related glenoid bone loss is reliable using the 3D ACSA method.

Editorial Commentary: Delphi Expert Consensus Clarifies Evidence-Based Medicine for Shoulder Instability and Bone Loss

Anterior glenohumeral instability with glenoid bone loss is a difficult problem and often requires open procedures with bone block augmentation. The current evidence suggests glenoid bone loss of 20% or more as a cutoff value indicating augmentation. Expert consensus-based techniques, such as the Delphi, clarify evidence-based medicine and allow pooling of expert opinion in a scientific fashion. These methods suggest that 3-dimensional computed tomography should be used to evaluate bone loss, previous dislocations, or failed soft-tissue surgery; Hill-Sachs lesions are poorly quantified by standard imaging; and, in cases with a bone deficit of >20%, glenoid bone graft should be considered. No consensus was reached regarding glenoid track evaluation, magnetic resonance imaging for evaluation of bone loss, safety of arthroscopic Latarjet, remplissage use for Hill-Sachs lesions of less than 30%, indications for a shoulder sling for 4 to 6 weeks after surgery, or postoperative rehabilitation timing and range-of-motion protocols.

Effectiveness of Latarjet for anterior shoulder instability in patients with seizure disorder

Background

A paucity of literature exists on the outcomes after Latarjet for anterior shoulder instability in patients with seizure disorders (SDs). The purpose of this study was to determine the effectiveness of the Latarjet procedure for anterior shoulder instability in patients with SDs.

Methods

A retrospective review of patients undergoing Latarjet from 2013 to 2017 for anterior shoulder instability with minimum 2 years of clinical follow-up was performed. Patients were divided into two groups: patients diagnosed with SD, and patients without a history of seizure (control). Demographics, indications, SD details, and postoperative outcomes were collected. The incidence of complications, recurrent instability, revision surgery, and repeat seizure(s) were also examined.

Results

A total of 53 patients were identified, including 10 shoulders in 9 patients with an SD (88.9% male; mean age, 29.2 years [range, 20-37]), and 44 shoulders in 44 non-SD patients (86.4% male; mean age, 30.3 years [range, 18-52]). The mean follow-up time was 3.4 (range, 2.2-4.8) and 3.8 (range, 2.1-5.6) years in the SD and control group, respectively. During the follow-up period, 4 of 9 (44.4%) patients with an SD (50% shoulders) had a recurrent seizure postoperatively. Of those 4 patients, three sustained a recurrent dislocation of the operative shoulder(s) resulting from a postoperative seizure, including one who dislocated bilateral shoulders from a single seizure event after bilateral Latarjet procedures. There was no recurrent instability in patients who did not sustain a seizure in the postoperative period. Having a seizure in the postoperative period significantly increased the risk of recurrent dislocation (OR = 39.9, P = 0.04).

Conclusions

Latarjet is a successful operation for recurrent anterior shoulder instability in patients without an SD. While it can still be successful in patients with SD, adequate control of seizures postoperatively is paramount to prevent recurrent instability episodes. Patients with an SD can be advised that if their seizures can remain controlled, they have a high likelihood of clinical success equal to that of patients without an SD.

Mathematical modeling of glenoid bone loss demonstrate differences in calculations that May affect surgical decision making

Objective

Two glenoid bone loss calculations are compared across a range of anatomic glenoid sizes.

Methods

20 cadaveric paired glenoid diameters were measured to create glenoid models with bone loss calculated in 1 mm linear increments up to 50% bone loss comparing the linear measurement percentage (LMP) to the circle line method (CLM) gold standard.

Results

The LMP overestimates glenoid bone loss at every potential 1 mm increment across each glenoid model until bone loss reaches 50%.

Conclusion

The widely-used LMP method overestimates bone loss compared to a gold standard potentially misguiding surgeons towards bony reconstruction in shoulder instability during preoperative planning.

Accuracy of Currently Available Methods in Quantifying Anterior Glenoid Bone Loss: Controversy Regarding Gold Standard-A Systematic Review

PURPOSE

To determine the accuracy of glenoid bone loss-measuring methods and assess the influence of the imaging modality on the accuracy of the measurement methods.

METHODS

A literature search was performed in the PubMed (MEDLINE), Embase, and Cochrane databases from 1994 to June 11, 2019. The guidelines and algorithm of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) were used. Included for analysis were articles reporting the accuracy of glenoid bone loss-measuring methods in patients with anterior shoulder instability by comparing an index test and a reference test. Furthermore, articles were included if anterior glenoid bone loss was quantified using a ruler during arthroscopy or by measurements on plain radiograph(s), computed tomography (CT) images, or magnetic resonance images in living humans. The risk of bias was determined using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool.

RESULTS

Twenty-one studies were included, showing 17 different methods. Three studies reported on the accuracy of methods performed on 3-dimensional CT. Two studies determined the accuracy of glenoid bone loss-measuring methods performed on radiography by comparing them with methods performed on 3-dimensional CT. Six studies determined the accuracy of methods performed using imaging modalities with an arthroscopic method as the reference. Eight studies reported on the influence of the imaging modality on the accuracy of the methods. There was no consensus regarding the gold standard. Because of the heterogeneity of the data, a quantitative analysis was not feasible.

CONCLUSIONS

Consensus regarding the gold standard in measuring glenoid bone loss is lacking. The use of heterogeneous data and varying methods contributes to differences in the gold standard, and accuracy therefore cannot be determined.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II, III, and IV studies.

Use of the Contralateral Glenoid for Calculation of Glenoid Bone Loss: A Cadaveric Anthropometric Study

PURPOSE

The purpose of this study was to determine if there are significant side-to-side anthropometric differences between paired glenoids.

METHODS

Forty-six matched-pair cadaver glenoids were harvested, and their glenoid heights (GHs) and glenoid widths (GWs) were measured with digital calipers. The glenoid surface area was calculated using the standard assumption that the inferior two-thirds of the glenoid is a perfect circle.

RESULTS

There was a statistically significant difference between matched-pair GHs of 0.96 ± 3.07 mm (P = .020) and GWs of 0.46 ± 1.64 mm (P = .033). There was a significant difference of glenoid cavity area of 20.30 ± 81.53 mm2 (P = .044), or a difference of ∼3%. A total of 4 of 46 pairs of glenoids (8.6%) showed a difference in width >3 mm.

CONCLUSIONS

This study demonstrates the fallacy of use of the contralateral glenoid in measuring glenoid bone loss. Although many paired samples exhibited similar side-to-side glenoid measurements, the number of cadaveric pairs that showed differences of >3 mm was substantial. Caution should be taken when using calculation methods that include this assumption for surgical decision making, as surface area, GW, and GH were all shown to have statistically significant side-to-side differences in their measurements.

CLINICAL RELEVANCE

Many methods exist for measuring glenoid bone loss after anterior shoulder dislocation, but some of the current methods may be inaccurate and lead to unreliable estimations.

Latarjet Procedure for the Treatment of Anterior Glenohumeral Instability

Anterior glenohumeral instability is common, with 21.9 first-time dislocations per 100,000 individuals per year. Recurrent instability is more likely to occur in patients who are younger, of male sex, and have bone defects or ligament laxity. The open Latarjet procedure is effective for the treatment of recurrent anterior glenohumeral instability and is preferred over arthroscopic Bankart repair in the presence of glenoid bone loss. The Latarjet procedure involves transferring the coracoid to the anterior aspect of the glenoid in the following steps. Step 1: Preoperative planning includes an assessment of glenoid deformation and the integrity of the rotator cuff. The degree of bone loss is measured with use of the circle-line method. Step 2: The patient is in the beach-chair position with the arm in a pneumatic arm holder. A parallel drill guide system with 3.75-mm cannulated screws is utilized. Step 3: A 5-to-6-cm incision is made along the anterior axillary line. The deltopectoral interval is established, and the cephalic vein is mobilized laterally. The coracoacromial ligament is transected 15 mm lateral to the coracoid to allow later repair to the anterior capsule. The pectoralis minor is released subperiosteally off the medial coracoid. A 90° oscillating saw is used to transect the coracoid medially to laterally. The coracohumeral ligament is released. Step 4: Two 4.0-mm drill-holes are made 1 cm apart through the coracoid. The undersurface is decorticated. Step 5: The subscapularis is split at the junction of the upper two-thirds and lower one-third. A longitudinal capsulotomy is performed parallel to the glenoid. Step 6: Soft tissue, including the capsule and labrum, is removed from the anterior aspect of the glenoid. The bone is decorticated with an osteotome and a rasp. Step 7: The coracoid is positioned flush or 1 mm recessed relative to the glenoid. Two 1.6-mm guidewires are placed with use of a parallel drill guide followed by a cannulated reamer and two 3.75-mm cannulated screws. Step 8: The coracoacromial ligament is repaired to the capsule. Step 9: The subscapularis split is repaired laterally. The deltopectoral interval and skin are closed in a standard fashion. A standardized rehabilitation protocol is employed postoperatively. The Latarjet procedure results in significantly lower rates of recurrent glenohumeral instability and revision compared with the arthroscopic Bankart procedure (3% and 1% compared with 28.4% and 21%, respectively); however, complication rates as high as 30% have been reported, as well as a risk for nerve injury. The videos included in this article highlight the critical steps required to optimize outcomes and minimize complications when performing the Latarjet procedure.

Editorial Commentary: Methodology of Measuring Bone Loss in Recurrent Shoulder Instability Surgery: Traditional Computed Tomography Scan and Magnetic Resonance Imaging Do Not Tell the Full Story

When measuring bone loss in recurrent shoulder instability, both computed tomography (CT) scan and magnetic resonance imaging (MRI) are accurate using the circle method. However, measurement of on- versus off-track lesions can be inconsistent, and measuring Hill-Sachs lesions on MRI relative to an extrapolated rotator cuff attachment is difficult. In the end, determination of on- versus off-track treatment is quite difficult, and for this determination, differences between CT scan and MRI may be clinically imperceptible. Thus, for now, we, and we believe, other surgeons will continue to stick with the circle technique when determining individual patient treatment for recurrent shoulder instability.

Progression of Erosive Changes of Glenoid Rim After Arthroscopic Bankart Repair

PURPOSE

To evaluate changes of the glenoid after arthroscopic Bankart repair (ABR) in patients with different preoperative glenoid structures.

METHODS

Patients who underwent ABR for traumatic anterior shoulder instability were retrospectively investigated. They were divided into 3 groups on the basis of preoperative glenoid structure by computed tomography (CT): normal glenoid (group N), glenoid erosion (group E), or glenoid defect associated with a bony Bankart lesion (group B). Shoulders in group B were also stratified according to the postoperative status of the bone fragment (union, nonunion, or resorbed). Postoperative changes of glenoid width (Δ) (increase: Δ ≥5%, stable: Δ >-5% to <5%, decrease: Δ ≤-5%) and the extent of glenoid bone loss were investigated by 3-dimensional CT.

RESULTS

A total of 186 shoulders were divided into 3 groups: group N (n = 61), group E (n = 46), and group B (n = 79). At initial postoperative CT, the glenoid width was decreased in 41 shoulders, stable in 20 shoulders, and increased in no shoulders from group N. The respective numbers were 27, 18, and 1 in group E, and 50, 22, and 7 in group B. The glenoid width was reduced in all groups (mean percent change: -8.8%, -5.9%, and -6.1%, respectively). In group B, glenoid width decreased in most of the shoulders without bone union. The glenoid bone loss on the preoperative and postoperative final CT was, respectively, 0% and 8.6% in group N (P < .0001), 9.9% and 12.4% in group E (P = .03), and 10.4% and 7.2% in group B (P = .01). Final glenoid bone loss >13.5% was recognized in 18.2% of group N, 35.7% of group E, and 21.8% of group B.

CONCLUSIONS

Glenoid width often decreased after ABR because of anterior glenoid rim erosion, and this change was frequent in patients with preoperative normal glenoid, glenoid erosion, or without postoperative union of a bony Bankart lesion.

LEVEL OF EVIDENCE

Level 3, Case-control study.

Does Bone Loss Imaging Modality, Measurement Methodology, and Interobserver Reliability Alter Treatment in Glenohumeral Instability?

PURPOSE

To determine, in the context of measuring bone loss in shoulder instability, whether measurement differences between magnetic resonance imaging (MRI) and computed tomography (CT), linear-based and area-based methods, and observers altered the proposed treatment when a standardized algorithm was applied.

METHODS

This was a retrospective, comparative imaging study of preoperative patients with anterior shoulder instability with both an MRI and CT scan within 1 year of one another. On parasagittal images reoriented en face to the glenoid, 2 attending orthopaedic surgeons measured glenoid width, glenoid area, glenoid defect width, and glenoid defect area. On axial images maximal Hill-Sachs width was measured. From these, linear percent glenoid bone loss (%GBL) and area %GBL were calculated, and on-versus off-track was determined. With these results, a recommended treatment was determined by applying a standardized algorithm, in which the Latarjet procedure was selected for %GBL >20%, arthroscopic labral repair and remplissage for off-track lesions with %GBL <20%, and arthroscopic labral repair on-track shoulders with %GBL <20%.

RESULTS

In total, 53 patients with mean ± standard deviation 45 ± 83 days between scans were include with a CT linear %GBL of 23.5 ± 9.6% (range 0%-47%). CT lead to larger measurements of %GBL than MRI (linear P = .008, area P = .003), and fewer shoulders being considered on-track (33.0% vs 40.5%), which would alter treatment in 25% to 34%. Linear measurements produced larger values for %GBL (CT, P < .001; MRI, P < .001), which would alter treatment in 25%. For %GBL, inter-rater reliability was good, with intraclass correlation coefficients varying from 0.727 to 0.832 and Kappa varying from 0.57 to 0.62, but these inter-rater differences would alter treatment in 31%.

CONCLUSIONS

The significant differences in bone loss measurement between imaging modality, measurement method, and observers may lead to differences in treatment in up to 34% of cases. Linear CT measurements resulted in the most aggressive treatment recommendations.

LEVEL OF EVIDENCE

Retrospective Comparative Study: Diagnostic, Level III.

Reliability of the measurement of glenoid bone defect in anterior shoulder instability

Background:

The size of the glenoid bone defect is an important index in selecting the appropriate treatment for anterior shoulder instability. However, the reliability of glenoid bone defect measurement is controversial. The purpose of the present study was to investigate the reliabilities of measurements of the glenoid bone defect on computed tomography and to explore the predisposing factors leading to inconsistency of these measurements.

Methods:

The study population comprised 69 consecutive patients who underwent surgery for recurrent anterior shoulder dislocation in Peking University Fourth School of Clinical Medicine from March 2016 to January 2017. The glenoid bone defect was measured by three surgeons on ‘self-confirmed’ and ‘designated’ 3-D en-face views, and repeated after an interval of 3 months. Measurements included the ratio of the defect area to the best-fit circle area, and the ratio of the defect width to the diameter of the best-fit circle. The inter- and intra-observer reliabilities of the measurements were evaluated using intraclass correlation coefficients (ICCs). The maximum absolute inter- and intra-observer differences and the cumulative percentages of cases with inter- and intra-observer differences greater than these respective levels were calculated.

Results:

Almost all linear defect values were bigger than the areal defect values. The inter-observer ICCs for the areal defect were 0.557 and 0.513 in the ‘self-confirmed’ group and 0.549 and 0.431 in the ‘designated’ group. The inter-observer reliabilities for the linear defect were moderate or fair in the ‘self-confirmed’ group (ICC = 0.446, 0.374) and ‘designated’ group (ICC = 0.402, 0.327). The ICCs for intra-observer measurements were higher than those for inter-observer measurements. The respective maximum inter- and intra-observer absolute differences were 13.9% and 13.2% in the ‘self-confirmed’ group, and 15.8% and 9.8% in the ‘designated’ group.

Conclusions:

The areal measurement of the glenoid bone defect is more reliable than the linear measurement. The reliability of the glenoid defect areal measurement is moderate or worse, suggesting that a more accurate and objective measurement method is needed in both en-face view and best-fit circle determination. Subjective factors affecting the glenoid bone loss measurement should be minimized.

Insufficient consensus regarding circle size and bone loss width using the ratio-"best fit circle"-method even with three-dimensional computed tomography

PURPOSE

Glenoid bone integrity is crucial for shoulder stability. The purpose of this study was to investigate a non-invasive method for quantifying bone loss regarding reliability and accuracy to detect glenoid bone deficiency in standard two-dimensional (2D) and three-dimensional (3D) computed tomography (CT) measurements at different time points. It was hypothesized that the diameter of the circle used would significantly differ between raters, rendering this method inaccurate and not allowing for an exact estimation of glenoid defect size.

METHODS

Fifty-two shoulder CTs from 26 patients (26 2D-CTs; 26 3D-CTs) with anterior glenoid bone defects were evaluated by 6 raters at time 0 (T0) and at least 3 weeks after (T1) to assess the glenoid bone defect using the ratio method ("best fit circle"). Inter- and intra-rater differences concerning circle dimensions (circle diameter), measured width of bone loss and calculated percentage of bone loss (length-width-ratio) were compared in 2D- versus 3D-CT scans. The intraclass coefficient (ICC) was used to determine the inter- and intra-rater agreement.

RESULTS

The mean circle diameter difference in 2D-CT was 2.0 ± 1.9 mm versus 1.8 ± 1.5 mm in 3D-CT, respectively (p < 0.01). Mean width of bone loss in 2D-CT was 1.9 ± 1.7 mm compared to 1.7 ± 1.5 mm in 3D-CT, respectively (p < 0.01). The mean difference of bone loss percentage was 5.1 ± 4.8% in 2D-CT and 4.8 ± 4.5% in 3D-CT (p < 0.01). No significant differences concerning circle diameter, bone loss width and bone loss percentage were detected comparing T0 and T1. Circle diameter, bone loss width and bone loss percentage measurements in 3D-CT were significantly smaller compared to 2D-CT at T0 and T1 (p < 0.01). Agreement (ICC) was fair to good for all indicators of circle diameter (range 0.76-0.83), bone loss width (range 0.76-0.86) and percentage of bone loss (range 0.85-0.91). Overall, 3D-CT showed superior agreement compared to 2D-CT.

CONCLUSION

The ratio method varies in all glenoid parameters and is not valid for consistently quantifying glenoid bone defects even in 3D computed tomography. This must be taken into consideration when determining proper surgical treatment. The degree of glenoid bone loss alone should not be used to decide for or against a bony procedure. Rather, it is more important to define a defect size as "critical" and to also take other patient-specific factors into consideration so that the best treatment option can be undertaken. Application of the "best fitting circle" is a source of error when using the ratio method; therefore, care should be taken when measuring the circle diameter.

LEVEL OF EVIDENCE

III.

Management of Recurrent Anterior Shoulder Instability With Bipolar Bone Loss: A Systematic Review to Assess Critical Bone Loss Amounts

BACKGROUND

There is increasing evidence to suggest that the amount of glenoid bone loss to indicate bone block procedures may be lower than previously thought, particularly in the presence of a Hill-Sachs defect.

PURPOSE

To better establish treatment recommendations for anterior shoulder instability among patients with bipolar bone lesions.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

A systematic review of the literature was performed with PubMed, EMBASE, Cochrane Library, and Scopus databases according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. Studies evaluating outcomes of operative management in anterior shoulder instability that also reported glenoid bone loss in the presence of Hill-Sachs defects were included. Recurrence rates, glenoid bone loss, and humeral bone loss were pooled and analyzed with forest plots stratified by surgical procedure. Methods of quantification were analyzed for each article qualitatively.

RESULTS

Thirteen articles were included in the final analysis, with a total of 778 patients. The mean ± SD age was 24.9 ± 8.6 years. The mean follow-up was 30.1 months (range, 11-240 months). Only 13 of 408 (3.2%) reviewed bipolar bone loss articles quantified humeral and/or glenoid bone loss. Latarjet procedures had the greatest glenoid bone loss (21.7%; 95% CI, 14.8%-28.6%), followed by Bankart repairs (13.1%; 95% CI, 9.0%-17.2%), and remplissage (11.7%; 95% CI, 5.5%-18.0%). Humeral bone loss was primarily reported as percentage bone loss (22.2%; 95% CI, 13.1%-31.3% in Bankart repairs and 31.7%; 95% CI, 21.6%-41.1% in Latarjet) or as volumetric defects (439.1 mm³; 95% CI, 336.3-541.9 mm³ in Bankart repairs and 366.0 mm³; 95% CI, 258.4-475.4 mm³ in remplissage). Recurrence rates were as follows: Bankart repairs, 19.5% (95% CI, 14.5%-25.8%); remplissage, 4.4% (95% CI, 1.3%-14.0%); and Latarjet, 8.7% (95% CI, 5.0%-14.7%). Bankart repairs were associated with significantly greater recurrence of instability in included articles (P = .013).

CONCLUSION

There exists a need for universal and consistent preoperative measurement of humeral-sided bone loss. The presence of concomitant Hill-Sachs defects with glenoid pathology should warrant more aggressive operative management through use of bone block procedures. Previously established values of critical glenoid bone loss are not equally relevant in the presence of bipolar bone loss.

Sub-region based radiomics analysis for survival prediction in oesophageal tumours treated by definitive concurrent chemoradiotherapy

BACKGROUND

Evaluating clinical outcome prior to concurrent chemoradiotherapy remains challenging for oesophageal squamous cell carcinoma (OSCC) as traditional prognostic markers are assessed at the completion of treatment. Herein, we investigated the potential of using sub-region radiomics as a novel tumour biomarker in predicting overall survival of OSCC patients treated by concurrent chemoradiotherapy.

METHODS

Independent patient cohorts from two hospitals were included for training (n = 87) and validation (n = 46). Radiomics features were extracted from sub-regions clustered from patients' tumour regions using K-means method. The LASSO regression for 'Cox' method was used for feature selection. The survival prediction model was constructed based on the sub-region radiomics features using the Cox proportional hazards model. The clinical and biological significance of radiomics features were assessed by correlation analysis of clinical characteristics and copy number alterations(CNAs) in the validation dataset.

FINDINGS

The overall survival prediction model combining with seven sub-regional radiomics features was constructed. The C-indexes of the proposed model were 0.729 (0.656-0.801, 95% CI) and 0.705 (0.628-0.782, 95%CI) in the training and validation cohorts, respectively. The 3-year survival receiver operating characteristic (ROC) curve showed an area under the ROC curve of 0.811 (0.670-0.952, 95%CI) in training and 0.805 (0.638-0.973, 95%CI) in validation. The correlation analysis showed a significant correlation between radiomics features and CNAs.

INTERPRETATION

The proposed sub-regional radiomics model could predict the overall survival risk for patients with OSCC treated by definitive concurrent chemoradiotherapy. FUND: This work was supported by the Zhejiang Provincial Foundation for Natural Sciences, National Natural Science Foundation of China.

Arthroscopic Remplissage for Anterior Shoulder Instability: A Systematic Review of Clinical and Biomechanical Studies

PURPOSE

To examine the clinical outcomes and biomechanical data supporting the use of the remplissage procedure.

METHODS

A query of the Embase, PubMed, Scopus, and Web of Science databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines from 2000 to 2017. Data were extracted from included studies for a qualitative review of both clinical and biomechanical outcomes.

RESULTS

After review, 18 clinical and 10 biomechanical studies were available for analysis; 10 of 18 clinical studies (55.6%) were Level IV evidence. Within the clinical studies, there were 567 patients (570 shoulders) evaluated with follow-up ranging from 6 to 180 months. Overall, 5.8% of shoulders (33 of 570) displayed recurrent instability after arthroscopic remplissage. Of the shoulders with recurrent instability, 42.4% of shoulders (14 of 33) underwent further surgical management. In all studies evaluating pre- and postoperative patient-reported outcomes, the arthroscopic remplissage procedure improved patient-reported outcomes a statistically significant amount postoperatively. Within individual clinical studies, external rotation with the arm in neutral was the most consistently limited range of motion (ROM) parameter, with deficits compared with the contralateral shoulder ranging from 9° to 14°. Biomechanical analysis appeared to corroborate the clinical results, although significant conclusions were limited by heterogeneity of reporting.

CONCLUSIONS

Arthroscopic remplissage performed in conjunction with arthroscopic Bankart repair is a safe and effective procedure for patients with engaging Hill-Sachs lesions and subcritical glenoid bone loss. Although both the included clinical and biomechanical studies would suggest minimal changes in glenohumeral ROM following the remplissage procedure, strong conclusions are limited by the heterogeneity in reporting ROM data and lack of comparative studies.

LEVEL OF EVIDENCE

IV, systematic review.

Variations in the Anatomic Morphology of the Lateral Distal Tibia: Surgical Implications for Distal Tibial Allograft Glenoid Reconstruction

BACKGROUND

Distal tibial allograft glenoid augmentation has been introduced as a viable treatment approach for glenoid bone loss in conjunction with shoulder instability. No previous study, however, has assessed the morphologic variation of the distal tibia at the incisura as it relates to graft dimensions for glenoid augmentation. Increased concavity at the lateral distal tibia necessitates removal of the lateral cortex to obtain a flat surface, which may have implications for the strength of surgical fixation.

PURPOSE

To assess the morphologic variation of the distal tibia at the incisura as it relates to graft dimensions for glenoid augmentation.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Magnetic resonance images of the ankle were reviewed for morphology assessment of the appearance and depth of the distal tibia. A classification system was created reflecting the suitability for glenoid augmentation. Type A tibias contained a flat contour of the lateral tibia at the articular surface, indicative of an ideal graft. Type B tibias had slight concavity with a central depth <5 mm and were deemed acceptable grafts. Type C tibias had deep concavity with a central depth >5 mm and were deemed unacceptable. Statistical analysis was performed via univariate analyses to compare patient demographics against acceptable morphology for glenoid augmentation.

RESULTS

Eighty-five study patients met inclusion criteria (53 male, 32 female; mean age ± SD, 35.1 ± 10.3 years). Overall, 12 patients (14.1%) demonstrated type A morphology, with 61 patients (71.8%) having type B morphology for a total of 85.9% of acceptable grafts for glenoid augmentation. The interrater reliability was moderate to strong between observers (kappa value = 0.841). On univariate analysis, sex was the only variable significantly associated with an acceptable graft, with 100% of female patients having acceptable morphology, as compared with 77% of male patients ( P = .004).

CONCLUSION

Variable morphology of the distal tibia at the incisura was found: 14.1% of patients demonstrated an ideal morphology for glenoid augmentation; an additional 71.8% were deemed suitable for graft usage; and 14.1% of tibias had unacceptable morphology. Sex was a significant factor for predicting acceptable grafts.

CLINICAL RELEVANCE

This information will assist surgeons in accepting or rejecting grafts based on the epidemiology of the distal tibial morphology as it relates to glenoid augmentation.

Award Winning Research Recognized

One of the joys of the editorial team is selecting the annual Journal Awards. Recognizing research excellence is what we do. If a manuscript was ultimately selected for publication, it is already excellent, as we publish less than 20% of original scientific article submissions, and we received more than 1,300 such submissions in 2017. To be one of our award winners is to be truly "elite."