Three-dimensional volume measurement of coracoid graft osteolysis after arthroscopic Latarjet procedure

Graft Position, Healing, and Resorption in Anterior Glenohumeral Instability: A Comparison of 4 Glenoid Augmentation Techniques

Background

The success of glenoid augmentation procedures depends on accurate placement and healing of the graft to the glenoid. Different glenoid augmentation techniques have been described, but no comparative studies between them exist.

Purpose

To assess the bone graft position, healing, and resorption in a group of patients treated with 1 of 4 procedures: arthroscopic anterior bone-block procedure using either (1) fresh-frozen iliac crest allograft or (2) iliac crest autograft, (3) open Latarjet, or (4) arthroscopic Latarjet.

Study Design

Cohort study; Level of evidence, 3.

Methods

A total of 40 patients (87.5% men; mean age, 29.5 ± 7.9 years) were included, with 10 patients in each of the procedure groups. The graft position in the axial and sagittal planes was assessed on postoperative computed tomography (CT). Graft healing and resorption were assessed in a second CT scan performed 1 year postoperatively. Qualitative variables were compared between the 4 procedures using the chi-square test, and quantitative variables were compared with the Student t test or Mann-Whitney U test.

Results

No differences were found between the procedures in the axial or sagittal position. The healing rate was significantly lower in the allograft bone-block group (20%) compared with the autograft bone-block (80%), open Latarjet (90%), and arthroscopic Latarjet (90%) groups (P < .001). Graft resorption developed in 17 of 40 (42.5%) cases overall. Osteolysis occurred in 100% of cases in the allograft bone-block group compared with 50% in the autograft group, 20% in the open Latarjet group, and 0% in the arthroscopic Latarjet group (P < .001). The glenoid surface area on 1-year CT scan was significantly lower in the allograft bone-block group compared with the autograft bone-block, open Latarjet, and arthroscopic Latarjet groups (P < .001).

Conclusion

Arthroscopic bone-block, open Latarjet, and arthroscopic Latarjet procedures provided accurate bone graft positioning. However, very high rates of osteolysis and nonunion were observed in the iliac crest fresh-frozen allograft bone-block procedure when compared with the other procedures.

Improvement of coracoid process union rates: a comparative study of conventional open and arthroscopic-assisted Bristow procedures for treating anterior shoulder instability in rugby players

BACKGROUND

The Bristow coracoid transfer procedure is a reliable technique for treating anterior shoulder instability in patients with large glenoid bone loss or those involved in collision sports. However, its success is marred by its inferior bone union rate of the coracoid process as compared to the Latarjet procedure. This study aimed to evaluate whether arthroscopic confirmation of the secured coracoid fixation during the Bristow procedure improves the bone union rate and clinical outcomes as compared to the open procedure.

METHODS

We retrospectively reviewed 104 rugby players (n = 111 shoulders) who underwent an open (n = 66 shoulders) or arthroscopy (AS)-assisted (n = 45 shoulders) Bristow procedure at our center from 2007 to April 2019. In the AS-assisted group, the screw fixation and coracoid stability and contact were confirmed under arthroscopic visualization. Graft union was evaluated through computed tomography at 3 months, 6 months, and 1 year postoperatively. Patient-reported outcome measures were assessed based on the American Shoulder and Elbow Surgeons score, Rowe score, and satisfaction rate. Recurrence, the rate of return to play (RTP), and the frequency of pain after RTP were also assessed.

RESULTS

The mean follow-up period was 73.5 (range: 45-160) months for the open group and 32.3 (range: 24-56) months for the AS-assisted group. In the former, the rates of bone union were 50%, 72.7%, and 88.9% at 3 months, 6 months, and 1 year, respectively. In contrast, the AS-assisted group had significantly greater bone union rates-88.9%, 93.3%, and 95.6% at 3 months, 6 months, and 1 year, respectively. Both groups showed significant improvement in the American Shoulder and Elbow Surgeons and Rowe scores compared to preoperative values as well as high satisfaction rates (open: 92%; AS-assisted: 95.7%). There were no statistically significant differences in the recurrence and RTP rates as well as the frequency of pain after RTP between the 2 groups.

CONCLUSION

The AS-assisted procedure allows early and high bone healing without compromising the clinical outcomes.

Does previous arthroscopic Bankart repair influence coracoid graft osteolysis in Latarjet procedure? A case-control study with computed tomography scan data

BACKGROUND

The Latarjet procedure is commonly performed in the treatment of recurrent shoulder instability and is also indicated as a salvage procedure for recurrence after failed arthroscopic Bankart repair. Although this procedure has shown success, there has been an increased awareness of complications in recent studies, especially graft osteolysis. Most relevant research has focused on the pathophysiology, incidence, or location of graft osteolysis or the risk factors for graft osteolysis; however, the data are limited to primary Latarjet procedures. This study aimed to investigate the effect of previous arthroscopic Bankart repair surgery on coracoid bone graft osteolysis in the Latarjet procedure.

METHODS

This retrospective case-control study analyzed data from patients who underwent primary Latarjet procedures or revision Latarjet procedures following failed arthroscopic Bankart repair. Clinical outcome measures included range of motion, the Subjective Shoulder Value, and the Rowe score. Volumetric analysis of each transferred coracoid graft was performed using early postoperative and late postoperative computed tomography scan data, and the amount of graft osteolysis was then calculated as the percentage of volume reduction of each graft.

RESULTS

A total of 32 patients who met the inclusion criteria were included in this study, with 24 patients in the primary Latarjet group (group I) and 8 patients in the revision Latarjet group (group II). The mean age of the patients was 32.5 ± 7.7 years, and the mean follow-up duration was 52.1 ± 8.9 months. Both study groups showed significant improvement in the Subjective Shoulder Value compared with baseline (P < .05). Comparison of postoperative clinical outcome measures showed no significant difference in any outcome parameter between the 2 study groups (P > .05). No recurrence was observed during the follow-up period. A positive apprehension sign was present in 6 patients (25%) in group I and 4 patients (50%) in group II (P > .05). Analysis of radiologic data revealed that all patients underwent some degree of graft osteolysis, with varying osteolysis ratios between 12% and 98%. The mean osteolysis ratio of the coracoid graft was 67.3% ± 22.6% in group I and 69.4% ± 25.6% in group II, with no significant difference between the 2 groups (P > .05).

CONCLUSION

The findings of this study suggest that a considerable amount of coracoid graft osteolysis is observed after both primary Latarjet procedures and revision Latarjet procedures following failed arthroscopic Bankart repair. Previous arthroscopic Bankart repair did not seem to have a significant influence on the amount of graft osteolysis, and both primary and revision Latarjet procedures showed satisfactory clinical outcomes.

Stability of novel cow-hitch suture button coracoid bone graft fixation in Latarjet procedures: a biomechanical study

BACKGROUND

The Latarjet procedure is widely used to address anterior shoulder instability, especially in case of glenoid bone loss. Recently, cortical suture button fixation for coracoid transfer has been used to mitigate complications seen with screw placement. The aim of this biomechanical study was to evaluate the stability of a novel and cost-effective cow-hitch suture button technique, designed to be performed through a standard open deltopectoral approach, and compare this to a well-established double suture button technique.

MATERIALS AND METHODS

We randomly assigned 12 fresh frozen cadaveric shoulders to undergo the Latarjet procedure with either 4 suture button (S&N EndoButton) fixations (SB group; n = 6, age 72 ± 9.8 years) or cow-hitch suture button technique using a 1.7-mm FiberTape looped sequentially in 2 suture buttons (Arthrex Pectoralis Button) placed from anterior on the posterior glenoid (CH-SB group; n = 6, age 73 ± 9.3 years). After fixation, all shoulders underwent biomechanical testing with direct loading on the graft via a material testing system. Cyclic loading was performed for 100 cycles (10-100 N) to determine axial displacement with time; each graft was then monotonically loaded to failure.

RESULTS

The maximum cyclic displacement was 4.3 ± 1.6 mm for the cow-hitch suture button technique and 5.0 ± 1.7 mm for the standard double suture button technique (P = .46). Ultimate load to failure and stiffness were, respectively, 190 ± 82 N and 221 ± 124 N/mm for the CH-SB technique and 172 ± 48 N and 173 ± 34 N/mm for the standard double SB technique (P = .66 and .43). The most common failure mode was suture cut-through at the anteroinferior aspect of the glenoid for both fixation groups.

CONCLUSIONS

The cow-hitch suture button technique resulted in a similar elongation, stiffness, and failure load compared to an established double suture button technique. Therefore, this cost-effective fixation may be an alternative, eligible for open approaches, to the established double suture button techniques.

Clinical Outcomes, Union Rates, and Complications of Screw Versus Button Fixation in the Bristow-Latarjet Procedure for Anterior Shoulder Instability: A Systematic Review and Meta-Analysis

Background

The Latarjet procedure is a common procedure for treating critical glenoid bone loss in anterior shoulder instability. Implants such as the screw and cortical button are widely used. The aim of this study was to compare studies on screw versus button fixation techniques in the Bristow-Latarjet procedure for anterior shoulder instability in terms of clinical outcomes, union rates, and complications.

Methods

The PubMed, Scopus, and Embase databases were searched to find comparative studies that reported outcomes of using screw versus button fixation in the Bristow-Latarjet procedure following the 2020 Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Studies that directly compared the screw and button fixation techniques and provided postoperative patient-reported outcomes, union rates, or complications were included. The Methodology Index for Non-Randomized Research (MINORS) criteria were used to assess the quality of the included studies. Odds ratios (ORs) were calculated for dichotomous outcomes whereas mean differences were calculated for continuous outcomes.

Results

Five articles included a total of 877 shoulders. All five studies had level 3 evidence. There was no statistically significant difference between the two techniques using the Walch-Duplay score, visual analog scale for pain, American Shoulder and Elbow Surgeons score, Simple Shoulder Test, range of motion, and graft union rates. However, the button fixation technique had statistically significantly higher recurrence rates than the screw fixation technique (OR, 0.24; 95% confidence interval, 0.10-0.58; p = 0.001).

Conclusions

The screw fixation technique had statistically significantly lower recurrence rates than the button fixation technique. However, there was no significant difference between screw and button fixation techniques regarding postoperative patient-reported outcomes, range of motion, graft union rates, nerve injury rates, infection rates, and reoperation rates.

Bone formation of the coracoid bone graft after the Bristow procedure assessed using three-dimensional computed tomography

BACKGROUND

The Bristow procedure has been shown to be a reliable method to prevent recurrent anterior shoulder instability by compensating for glenoid bone loss and producing the sling effect. The degree of postoperative morphological change in the coracoid bone graft is speculated to influence glenohumeral joint stability; however, the details of these changes after the Bristow procedure remain unknown. This study was performed to quantify the postoperative change in the coracoid bone graft volume as assessed by three-dimensional computed tomography (3D-CT).

METHODS

The Bristow procedure was performed on 17 shoulders in 17 patients from August 2018 to January 2020. All patients were men, and their mean age at surgery was 17.9 years. The mean follow-up duration was 21.4 months. Within the first week after the operation (Time 0) and at the final follow-up, 3D-CT was used to determine the total coracoid bone graft volume. The clinical outcomes were evaluated using the Japanese Orthopaedic Association (JOA) shoulder score, the University of California Los Angeles (UCLA) shoulder score, and the Western Ontario Shoulder Instability Index (WOSI).

RESULTS

The mean volume of the total coracoid bone graft was 1.26 ± 0.29 cm3 at Time 0 and 1.90 ± 0.36 cm3 at the final follow-up (p < 0.0001). The mean JOA score, UCLA score, and WOSI were significantly better at the final follow-up than preoperatively (p < 0.001). No postoperative infection, neurovascular injury, or recurrent instability of the glenohumeral joint occurred.

CONCLUSIONS

In the Bristow procedure, the volume of the total coracoid bone graft as shown by 3D-CT was significantly greater at the final follow-up than at Time 0, and bone formation of the coracoid bone graft was found after the Bristow procedure.

Screw-Related Complications May Occur at a Greater Rate After Arthroscopic Versus Open Latarjet Procedure: A Systematic Review

Purpose

To determine the rate of complications attributable to the use of screw fixation during the Latarjet procedure and to delineate screw-related complications for open and arthroscopic Latarjet surgery.

Methods

A systematic review of the literature was performed by querying MEDLINE and EMBASE computerized databases for relevant articles that reported clinical outcomes associated with the Latarjet procedure. Clinical studies of open and/or arthroscopic Latarjet surgery that employed screw fixation of the coracoid were included in our analysis.

Results

From 692 articles identified initially, 32 studies met eligibility criteria. The study cohort comprised 2,758 shoulders, with a mean age of patients ranged from 17 to 62 years, and the mean duration of follow-up ranged from 0.3 to 25.6 years. Twenty-two studies reported outcomes of an open Latarjet technique whereas 10 studies reported on an arthroscopic Latarjet technique. Across all studies, the overall complication rate ranged from 1.4% to 36%. The rate of screw-related complications ranged from 0% to16%, and the rate of screw removal ranged from 0% to 18%. Among the subset of studies that reported specific indications for screw removal, the most common indications were pain and screw loosening. Reported rates of screw-removal among arthroscopic Latarjet procedures range from 0% to 18% and among open procedures range from 0% to 7.3%.

Conclusions

(1) Up to one-third of the overall surgical complications associated with the Latarjet procedure may be related to the use of screw fixation, (2) arthroscopic Latarjet procedure did not decrease the rate of screw related complications. The reported rate of screw-removal may be higher after the arthroscopic Latarjet procedures (up to 18%) than after open procedures (up to 7,3%), and is mainly indicated for persistent shoulder pain and/or screw loosening.

Level of Evidence

Level IV, systematic review of Level III-IV studies.

Radiological and Histological Analyses of Nonrigid Versus Rigid Fixation for Free Bone Block Procedures in a Rabbit Model of Glenoid Defects

BACKGROUND

Nonrigid fixation techniques have been recently introduced in free bone block (FBB) procedures to treat substantial glenoid bone loss in patients with anterior shoulder instability. However, the radiological and histological effectiveness of nonrigid fixation versus conventional rigid fixation have not been comprehensively understood in vivo.

PURPOSE

To (1) explore the radiological and histological characteristics of nonrigid fixation for FBB procedures in a rabbit model of glenoid defects and (2) further compare them with those of conventional rigid fixation.

STUDY DESIGN

Controlled laboratory study.

METHODS

Unilateral shoulder glenoid defects were created in 36 mature New Zealand White rabbits, of which 24 underwent FBB procedures using allogenic iliac crest bone and were randomly divided into rigid fixation (RF) and nonrigid fixation (N-RF) groups, with the remaining divided into 2 control groups: 6 with sham surgery for glenoid defects (GD group) and 6 native glenoids (normal group). In the RF and N-RF groups, 6 rabbits were sacrificed at 6 or 12 weeks postoperatively for radiological and histological analyses of the reconstructed glenoid, and all rabbits in the GD and normal groups were sacrificed at 12 weeks. The radiological glenoid morphology was evaluated via micro-computed tomography. Moreover, the graft-glenoid healing and graft remodeling processes were determined using histological staining.

RESULTS

At 6 weeks, both the N-RF and RF groups had similarly improved radiological axial radian and en face area of the glenoid compared with the GD group, but the N-RF group showed superiority in restoration of the glenoid radian and area compared with the RF group at 12 weeks, with the native glenoid as the baseline. Histologically, the bone graft in both groups was substantively integrated into the deficient glenoid neck at 6 and 12 weeks, showing similar osseous healing processes at the graft-glenoid junction. Moreover, the bone graft histologically presented similar regenerated vascular density, total graft bone, and integrated graft bone in both groups. In contrast, the N-RF group had a different remodeling profile on radiological and histological analyses regarding regional bone resorption, mineralization, and fibrous tissue replacement during osseointegration.

CONCLUSION

Compared with rigid fixation, nonrigid fixation resulted in superior reconstructed glenoid morphology radiologically and similar graft-glenoid osseous healing histologically, showing different graft remodeling profiles of regional bone resorption, mineralization, and fibrous tissue replacement.

CLINICAL RELEVANCE

The nonrigid fixation technique can be feasible for FBB procedures to treat glenoid bone loss in anterior shoulder instability. More clinical evidence is required to determine its pros and cons compared with conventional rigid fixation.

Coracoid graft resorption after the Latarjet procedure does not depend on the preoperative glenoid defect

BACKGROUND

The primary purpose was to compare coracoid graft resorption after the Latarjet procedure in patients without preoperative glenoid bone loss vs. those with more than critical glenoid loss. The secondary purposes were to compare the functional outcomes and to investigate the association of graft position, angle of the screws, preoperative glenoid defect, age at surgery, and smoking status with graft resorption.

METHODS

Sixty consecutive patients with recurrent anterior instability were treated by the Latarjet procedure as the index procedure, irrespective of the glenoid bone loss between 2018 and 2021. Fifty-five patients were evaluated via computed tomography scans after a minimum of 1 year after surgery (range: 1-4 years). Twenty-five patients had no prior glenoid defect (No-defect group), 24 patients had preoperative glenoid defects ≥15% (Critical defect group), and 6 patients had glenoid defects between 5% and 15%. The No-defect group (n = 25) was compared with the Critical defect group (n = 24). Multivariate logistical regression was performed to evaluate the association of independent factors with the grade of resorption for all 55 patients in the cohort.

RESULTS

Major graft resorption at the level of the superior screw was observed in 72%-84% of patients in the No-defect group (n = 25) and in 75%-83% of patients in the Critical defect group (n = 24) (P = 1, P = 1; no significant difference). No to mild resorption at the level of the inferior screw was observed in 96% of patients in the No-defect group and 100% of patients in the Critical defect group (P = 1; no significant difference). Postoperative Rowe scores (100 [95-100] vs. 100 [95-100]; P = .8) and shoulder subjective value (87 [11] vs. 86 [9]; P = .9) were not significantly different between the 2 groups. None of the independent factors, including the corresponding screw angle, the mediolateral graft positioning, prior glenoid defect, age, and smoking status, were associated with graft resorption in multivariate logistical regression.

CONCLUSIONS

Graft resorption after the Latarjet procedure does not depend on the preoperative glenoid defect. The coracoid graft may be mostly resorbed around the superior screw but mildly or none at the level of the inferior screw, but this graft resorption is not dependent on the smoking status, age, prior glenoid defect, mediolateral graft positioning, and the angle of the screws.

Arthroscopic double-button Latarjet osteolysis and remodeling at 1-year follow-up

HYPOTHESIS

The aim of this study was to evaluate the osteolysis rate, graft remodeling, and risk factors for osteolysis at the 1-year threshold after an arthroscopic Latarjet procedure with double-button fixation.

METHOD

In this multicenter, retrospective study, postoperative computed tomography scans obtained after an arthroscopic Latarjet procedure with double-button fixation to treat anterior shoulder instability were analyzed at 15 days and at 3, 6, and 12 months. Graft volume, dimensions, and morphologic remodeling were analyzed.

RESULTS

Twenty-seven patients were included (mean age, 26 years). At 1 year, osteolysis occurred in 19 of 27 patients (70%). The volume initially decreased until 6 months' follow-up (-35%; range, -75% to +26%) and then increased until our last follow-up. At 1 year, the graft volume decreased by 17% (range, -61% to +56%) compared with the immediate postoperative volume. In multivariate analysis, the rate of osteolysis was inversely associated with an unhealed graft at 3 months (P = .02; β coefficient = -44.50 [95% confidence interval, -81 to -8]). The maximal height of the graft significantly grew 0.2 cm (range, -55 to +124 mm) (P = .015). In the sagittal plane, osteolysis occurred in the superior part in 100% of patients (27 of 27) whereas bone formation occurred in the inferior part. In the axial plane, osteolysis occurred in the anterior part whereas bone formation occurred in the posterior part. In the articular part, the observed remodeling was aimed to obtain a new anatomic and congruent glenoid.

CONCLUSIONS

At 1 year after an arthroscopic Latarjet procedure with double-button fixation, osteolysis occurred in 70% of patients. The rate of osteolysis was 17% of the initial volume. Osteolysis occurred mainly during the first 6 months, in the anterior and superior parts. Remodeling led to a circular anatomic glenoid. This osteolysis did not cause any recurrence of instability or require revision surgery.

Validation of a Novel Patient Specific CT-Morphometric Technique for Quantifying Bone Graft Resorption Following the Latarjet Procedure

Bone graft resorption following the Latarjet procedure has received considerable concern. Current methods quantifying bone graft resorption rely on two-dimensional (2D) CT-scans or three-dimensional (3D) techniques, which do not represent the whole graft volume/resorption (i.e., 2D assessment) or expose patients to additional radiation (i.e., 3D assessment) as this technique relies on early postoperative CT-scans. The aim of the present study was to develop and validate a patient-specific, CT-morphometric technique combining image registration with 3D CT-reconstruction to quantify bone graft resorption following the Latarjet procedure for recurrent anterior shoulder instability. Pre-operative and final follow-up CT-scans were segmented to digitally reconstruct 3D scapula geometries. A virtual Latarjet procedure was then conducted to model the timepoint-0 graft volume, which was compared with the final follow-up graft volume. Graft resorption at final follow-up was highly correlated to the 2D gold standard-technique by Zhu (Kendall tau coefficient = 0.73; p < 0.001). The new technique was also found to have excellent inter- and intra-rater reliability (ICC values, 0.931 and 0.991; both p < 0.001). The main finding of this study is that the technique presented is a valid and reliable method that provides the advantage of 3D-assessment of graft resorption at long-term follow-up without the need of an early postoperative CT-scan.

[Short-term effectiveness of modified arthroscopic Latarjet procedure with double EndoButtons for recurrent anterior shoulder dislocation]

OBJECTIVE

To evaluate the short-term effectiveness of modified arthroscopic Latarjet procedure with double EndoButtons for recurrent anterior shoulder dislocation.

METHODS

Between January 2019 and November 2020, 36 patients with recurrent anterior shoulder dislocation were treated by modified arthroscopic Latarjet procedure with double EndoButtons. There were 26 males and 10 females, with an average age of 27.8 years (range, 18-36 years). The number of shoulder dislocations ranged from 3 to 12 times, with an average of 6.5 times. The disease duration ranged from 5 to 36 months, with an average of 16.2 months. Preoperative shoulder fear test was positive, and the Beighton score of joint relaxation was 0-4, with an average of 1.3. Imaging examination showed that the defect width of the ipsilateral glenoid bone was 16%-28%, with an average of 21.5%. Postoperative complications, recurrent dislocation, subluxation, and instability of shoulder joint were recorded. Shoulder range of motion was examined, including forward flexion, external rotation at side, external rotation at 90° abduction, and internal rotation. Shoulder joint function was evaluated by Walch-Duplay score, American Association for Shoulder and Elbow Surgery Score (ASES), and ROWE score. X-ray film and CT images were taken to observe the shaping of coracoid process graft.

RESULTS

All incisions healed by first intention, and no vascular or nerve injury occurred. All patients were followed up 12-28 months, with an average of 19.9 months. During follow-up, no shoulder dislocation recurred, and shoulder fear test was negative. At last follow-up, there was no significant difference in shoulder forward flexion, external rotation at side, external rotation at 90° abduction, and internal rotation when compared with preoperative values (P>0.05). The Walch-Duplay score, ASES score, and ROWE score of shoulder function significantly improved (P<0.05). Postoperative imaging examination showed that coracoid process graft was at the same level with the glenoid in 33 cases (91.7%), medial in 1 case (2.8%), and lateral in 2 cases (5.6%); the center of coracoid process graft was mainly located between 3 to 5 o'clock in 33 cases (91.7%), higher than 3 o'clock in 1 case (2.8%), and lower than 5 o'clock in 2 cases (5.6%). There was no obvious glenohumeral joint degeneration during follow-up, and the coracoid process graft gradually formed concentric circles with the humeral head.

CONCLUSION

The modified arthroscopic Latarjet procedure with double EndoButtons can effectively treat recurrent anterior shoulder dislocation, and the short-term effectiveness is satisfactory, and the position of coracoid process graft is accurate.

Comparison of two coracoid process transfer techniques on stress shielding using three-dimensional finite-element model

Background

We created patient-based 3D finite-element (FE) models that simulate the congruent-arc Latarjet (CAL) and traditional Latarjet (TL) procedures and then compared their stress distribution patterns with different arm positions and glenoid defects.

Methods

The computed tomography data of 10 adult patients (9 men and 1 woman, ages: 18–50 years) were used to develop the 3D FE glenohumeral joint models. Twenty-five and 35% bony defects were created on the anterior glenoid rim, and the coracoid process was transferred flush with the glenoid by the traditional and congruent-arc techniques using two half-threaded screws. A load was applied to the greater tuberosity toward the center of the glenoid, and a tensile force (20 N) was applied to the coracoid tip along the direction of the conjoint tendon. The distribution patterns of the von Mises stress in the traditional and congruent-arc Latarjet techniques were compared.

Results

The mean von Mises on the graft was significantly greater for the TL technique than for the CAL. While the von Mises stress was greater in the distal medial part of the graft in the TL models, a higher stress concentration was observed in the distal lateral edge of the coracoid graft in the CAL models. The proximal medial part of the graft exhibited significantly lower von Mises stress than the distal medial part when compared according to technique, defect size, and arm position. Increasing the glenoid defect from 25 to 35% resulted in a significant increase in stress on the lateral side of the graft in both models.

Conclusion

The stress distribution patterns and stress magnitude of the coracoid grafts differed according to the procedure. Due to placing less stress on the proximal–medial part of the graft, the CAL technique may lead to insufficient stimulation for bone formation at the graft–glenoid interface, resulting in a higher incidence of graft osteolysis.

Clinical relevance The CAL technique may lead to a higher incidence of graft osteolysis.

Level of evidence

Basic Science Study; Computer Modeling.

Implant-free iliac crest bone graft procedure shows anatomic remodelling without redislocation in recurrent anterior shoulder instability after short-term follow-up

INTRODUCTION

With the help of a J-shaped bicortical iliac crest bone graft, the morphology of the glenoid can be augmented without having to use screws to achieve glenohumeral stability. The aim of this retrospective clinical study was to evaluate the clinical stability and function of the shoulder joint as well as the radiological remodelling process and arthropathic outcomes following the J-bone graft technique.

MATERIALS AND METHODS

34 patients with recurrent shoulder dislocations and bony glenoid defects were treated with the J-bone graft technique between 2010 and 2018 at our level-I trauma centre. 15 patients (18 shoulders) could be recruited for the study. Pain levels, ASES, UCLA, SST, DASH, Rowe and WOSI Scores were collected using questionnaires. In 13 patients (16 shoulders) the Constant Score, ROM, CT with 3D reconstruction of the glenoid to assess the graft remodelling and X-rays were performed additionally.

RESULTS

None of the patients suffered subluxations or recurrent dislocations during the follow-up period. The overall complication rate was 11%. The evaluation using objective and subjective shoulder function scores yielded good-to-excellent results. Radiological assessment at follow-up showed a low rate of moderate-to-severe arthritis (12%) and a high rate of shoulders without any signs of arthritic degeneration (53%). The CT scans all revealed an almost complete restoration of the glenoid with none of the grafts being resorbed. A rise in the average glenoid circumference and glenoid area could be demonstrated between preoperative measurements (81.6 and 82.4%, respectively) and follow-up measurements (104 and 102.5%, respectively).

CONCLUSION

The results of this study show a successful stabilisation of the shoulder joint and a low complication rate following the J-bone graft technique. Remodelling of the bone graft could be demonstrated, which in turn led to an almost perfect glenoid surface area of 100%.

Open Bristow Versus Open Latarjet for Anterior Shoulder Instability in Rugby Players: Radiological and Clinical Outcomes

Background:

Coracoid transfer is a reliable method for managing anterior shoulder instability in athletes who play contact sports; however, differences between the Bristow and Latarjet procedures are unclear.

Purpose:

To compare clinical outcomes and rates of bone union and bone resorption of the coracoid process between the open Bristow and open Latarjet procedures in rugby players.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Rugby players who underwent an open Bristow or an open Latarjet procedure were retrospectively reviewed for anterior shoulder instability, and 66 shoulders in the Bristow group and 35 in the Latarjet group were included. Graft union and resorption were evaluated using computed tomography at 3 months to 1 year postoperatively. Patient-reported outcome measures (American Shoulder and Elbow Surgeons score, Rowe score, and satisfaction rate) were obtained at a mean follow-up of 74 months (range, 45-160 months) for Bristow and 64 months (range, 50-76 months) for Latarjet procedures. Recurrence and the rate of return to play (RTP), frequency of pain after RTP, and retirement rate after RTP were also assessed.

Results:

In 97.1% of the Latarjet procedure cases, bone union of the coracoid was achieved at 3 months postoperatively; however, bone union was achieved in only 72.7% of the Bristow procedure cases at 6 months postoperatively. Bone resorption of the coracoid process occurred in 6.1% of shoulders after the Bristow procedure, whereas 100% of shoulders showed bone resorption after the Latarjet procedure. No statistical differences were found in outcome scores between the 2 procedures. Subluxation and persistent pain after returning to sports were identified at a significantly higher rate in the Latarjet group (5 shoulders [14%] and 9 shoulders [26%], respectively) than in the Bristow group (2 shoulders [3%] and 2 shoulders [3%]) (P = .0471 and P = .001, respectively).

Conclusion:

The Latarjet procedure had an advantage in the early and high rate of bone union but was at a disadvantage in bone resorption compared with the Bristow procedure. Subluxation and pain after returning to sports were more frequent in patients who underwent the open Latarjet procedure than in those who underwent the open Bristow procedure.

Arthroscopic Technique for Distal Tibial Allograft Bone Augmentation With Suture Anchor Fixation for Anterior Shoulder Instability

Recurrent instability associated with glenoid bone loss is a commonly encountered problem after anterior shoulder dislocation. Surgical management with bony augmentation can be achieved with several allograft or autograft options. Fixation strategies also vary, including screw, suture button, or suture anchor fixation. Concerns exist regarding screw fixation because of the technical difficulty of a medial portal establishment, as well as the potential for graft osteolysis. Suture button fixation for osteochondral graft fixation has been previously described. However, no description of graft fixation using suture anchors exists. We describe an arthroscopic technique for glenoid augmentation using distal tibial allograft with suture anchor fixation.

Arthroscopic Latarjet: 2 or 4 Cortical Buttons for Coracoid Fixation? A Case-Control Comparative Study

BACKGROUND

While 2 screws are traditionally used for coracoid bone block fixation, no gold standard technique has yet been established when using cortical buttons.

PURPOSE

To compare anatomic and clinical outcomes of the arthroscopic Latarjet procedure using either 2 or 4 buttons for coracoid bone block fixation.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 23 patients with 4-button fixation (group 4B) were matched for age at surgery, sex, and follow-up to 46 patients who had 2-button fixation (group 2B). All patients underwent guided arthroscopic Latarjet (using coracoid and glenoid guides), and a tensioning device was used to rigidify the suture button construct and get intraoperative bone block compression. The primary outcome was assessment of bone block positioning and healing using computed tomography scans performed at 2 weeks and at least 6 months after surgery. The mean ± standard deviation follow-up was 49 ± 7 months (range, 24-64 months).

RESULTS

The bone block healing rate was similar in both groups: 91% in group 4B versus 95.5% in group 2B. The transferred coracoid was flush to the glenoid surface in 21 patients (91%) in group 4B and 44 patients (96%) in group 2B (P = .6); it was under the equator in 22 patients (96%) in group 4B and 44 patients (96%) in group 2B (P≥ .99). There was no secondary bone block displacement; the rate of bone block resorption was similar between the groups: 28% in group 4B and 23% in group 2B (P = .71). Patient-reported outcomes, return to sports, and satisfaction were also similar between the groups. The operating time was significantly longer in group 4B (95 vs 75 minutes; P = .009).

CONCLUSION

A 4-button fixation technique did not demonstrate any anatomic or clinical advantages when compared with a 2-button fixation technique, while making the procedure more complex and lengthening the operating time by 20 minutes. A 2-button fixation is simple, safe, and sufficient to solidly fix the transferred coracoid bone block. The use of drill guides allows accurate graft placement, while the use of a tensioning device to rigidify the suture button construct provides high rates of bone block healing with both techniques (>90%).

Intra-articular biomechanical environment following modified Bristow and Latarjet procedures in shoulders with large glenoid defects: relationship with postoperative complications

BACKGROUND

Although coracoid transfers including the modified Bristow and Latarjet procedures are widely used to treat anterior shoulder instability, the influence of the choice of procedure on the biomechanical outcomes is not well characterized. We aimed to clarify the intra-articular stress distribution following these 2 procedures using 3-dimensional finite-element analysis and to investigate the role of stress distribution in the pathophysiology of postoperative complications.

METHODS

Overall, 6 male patients aged 17-47 years with unilateral anterior shoulder instability were recruited. Computed tomographic digital imaging and communications in medicine (CT-DICOM) data of the contralateral (healthy) shoulder of each patient was obtained and used for developing the 3-dimensional normal glenohumeral joint model. A 25% bony defect was created in the anterior glenoid rim where the coracoid process was transferred in the standing and lying-down positions to create the Bristow and Latarjet models, respectively. The arm position was set as 0° or 90° abduction. The Young moduli of the humerus and scapula were calculated using CT data, and set as 35.0 MPa and 113.8 GPa for the articular cartilage and inserted screw, respectively. A compressive load (50 N) was applied to the greater tuberosity toward the center of the glenoid, and a tensile load (20 N) was applied to the tip of the coracoid in the direction of conjoint tendon. Elastic analysis was used to determine the equivalent stress distribution.

RESULTS

A significant reduction in mean equivalent stress was observed within the glenoid cartilage for both models (P = .031); however, a new stress concentration appeared within the grafted coracoid-facing region of the humeral-head cartilage in both models. The proximal half of the coracoid graft exhibited lower equivalent stress than the distal half in 5 of the 6 Latarjet models, whereas the proximal half showed higher equivalent stress than the distal half in all 6 Bristow models. High stress concentration was identified at the midpoint of the inserted screw in Bristow models.

DISCUSSION AND CONCLUSIONS

Intra-articular stress distribution may explain the different rates of postoperative complications associated with the modified Bristow and Latarjet procedures. New stress concentration within the humeral-head cartilage might contribute to the development of glenohumeral osteoarthritis following both procedures. Stress shielding in the proximal part of the coracoid graft might contribute to osteolysis following the Latarjet procedure. Surgeons should be aware of the risk of breakage of the inserted screw following the modified Bristow procedure.

Arthroscopic Autologous Scapular Spine Bone Graft Combined With Bankart Repair for Anterior Shoulder Instability With Subcritical (10%-15%) Glenoid Bone Loss

PURPOSE

The purpose of our study is to prove that the autologous scapular spine bone graft is an alternative for the treatment of anterior shoulder instability and the clinical and radiological results are promising.

METHOD

From July 2016 to August 2018, patients who were diagnosed as having anterior shoulder instability with subcritical (10%-15%) glenoid bone loss were treated by arthroscopic repair with autologous scapular spine bone graft. The inclusion criteria were (1) anterior shoulder instability underwent arthroscopic autologous scapular spine bone graft; (2) glenoid bone loss was within 10% to 15% (measured by Sugaya's method); (3) three complete sets of computed tomography (CT) scans (preoperative, 1 week after surgery, and 1 year after surgery) available; and (4) clinical follow-up time was at least 2 years. The exclusion criteria were (1) concomitant rotator cuff tear; (2) concomitant remplissage or SLAP repair; (3) previous surgery of the affected shoulder; (4) open surgery; and (5) incomplete radiological or clinical follow-up. The preoperative and postoperative Constant-Murley score, dietary approaches to stop hypertension (DASH) score, visual analog scale (VAS) score, and range of motion (ROM) were recorded. CT scans with 3-dimensional reconstruction were obtained at the first week after operation and at 1 year after operation; the graft resorption rate was consequently calculated.

RESULTS

Twenty-seven patients were qualified and enrolled in the study. No severe complication was recorded during follow-up. No redislocation or subluxation was found, and the apprehension tests were all negative. At the last follow-up, the mean Constant-Murley score was 89.74 ± 3.71, the mean DASH score was 9.77 ± 5.31, the mean VAS score was 0.74 ± 0.64, which are all improved significantly compared with preoperative scores (P = .00,.00,.00, respectively). At the last follow-up, the ROM including anterior flexion, external rotation by side, and the internal rotation were well restored without significant difference compared with the contralateral shoulder (P =.48, .08, .47, respectively). At 1 year after operation, the resorption rate of the bone graft was 19.4%.

CONCLUSION

This study found that anterior shoulder instability with subcritical (10%-15%) glenoid bone loss treated with arthroscopic autologous scapular spine bone graft with suture anchor fixation is safe and could achieve satisfactory result at short-term follow-up.

LEVEL OF EVIDENCE

Therapeutic case series.

Computed Tomography-Based Preoperative Planning Provides a Pathology and Morphology-Specific Approach to Glenohumeral Instability With Bone Loss

PURPOSE

To use computed tomography (CT) to determine a reproducible method of coracoid measurement to compare the ability of the classic Latarjet technique and the congruent arc modification (CAM) to restore native glenoid diameter and to develop a preoperative planning algorithm for glenoid restoration with a goal of achieving an on-track shoulder.

METHODS

Coracoid dimensions were measured on multiplanar reconstructed shoulder CT scans of patients aged 18 to 45 years obtained between December 1, 2019, and March 13, 2020. Patients were excluded if CT demonstrated osteophyte formation, glenoid dysplasia, coracoid fracture, or tumor. The proportion of glenoid diameter able to be restored using classic Latarjet technique and CAM were calculated. A treatment algorithm was proposed considering the amount of bone loss present and coracoid dimensions.

RESULTS

Coracoid dimensions of 117 consecutive patients were measured and varied considerably (length: 17.5-31.8 mm, width: 9.1-20.5 mm, thickness: 6.1-15.7 mm). While most patients had harvestable coracoid length ≥20 mm (male: 96.3% vs female: 94.4%, P = .65), only 27.8% of female patients had coracoid thickness ≥10 mm. When comparing Latarjet techniques, there was no difference in the proportion of patients in whom 30% glenoid diameter could be fully restored, but CAM was able to restore at least 35% in more male and female patients (98.8% vs 79.0% and 100% vs 61.1%, respectively, P = .00001). Intra- and inter-rater reliability was excellent ( intraclass correlation coefficient ≥0.950 for all dimensions).

CONCLUSIONS

We describe a reliable method of measuring coracoid dimensions for preoperative planning of glenoid restoration. The classic Latarjet technique reliably restores the glenoid anteroposterior diameter with bone loss of up to 30%. The majority of female patients have coracoid thickness <10 mm, which may increase the risk of graft fracture when using CAM. The decision to use the classic Latarjet technique or CAM considers each individual's glenoid and coracoid dimensions with a goal of achieving an on-track shoulder.

CLINICAL RELEVANCE

Our reliable method of coracoid measurement demonstrated the differing abilities of the classic Latarjet and CAM to restore the native glenoid diameter. An evidence-based algorithm using these measurements was developed to assist in preoperative planning for glenohumeral instability in the setting of bone loss, with a goal of achieving an on-track shoulder. Alternative techniques may be considered if an on-track shoulder cannot be achieved with Latarjet.

Restoration of the Posterior Glenoid in Recurrent Posterior Shoulder Instability Using an Arthroscopically Placed Iliac Crest Bone Graft: A Computed Tomography-Based Analysis

Background

Posterior shoulder instability is uncommon, and its treatment is a challenging problem. An arthroscopically assisted technique for posterior iliac crest bone grafting (ICBG) has shown promising short- and long-term clinical results. Changes as shown on imaging scans after posterior ICBG for posterior shoulder instability have not been investigated in the recent literature.

Purpose

To evaluate changes on computed tomography (CT) after arthroscopically assisted posterior ICBG and to assess clinical outcomes.

Study Design

Case series; Level of evidence, 4.

Methods

Patients with preoperative CT scans and at least 2 postoperative CT scans with a minimum follow-up of 2 years were included in the evaluation. Of 49 initial patients, 17 (follow-up rate, 35%) met the inclusion criteria and were available for follow-up. We measured the glenoid version angle and the glenohumeral and scapulohumeral indices on the preoperative CT scans and compared them with measurements on the postoperative CT scans. Postoperatively, graft surface, resorption, and defect coverage were measured and compared with those at early follow-up (within 16 months) and final follow-up (mean ± SD, 6.6 ± 2.8 years).

Results

The mean preoperative glenoid version was -17° ± 13.5°, which was corrected to -9.9° ± 11.9° at final follow-up (P < .001). The humeral head was able to be recentered and reached normal values as indicated by the glenohumeral index (51.8% ± 6%; P = .042) and scapulohumeral index (59.6% ± 10.2%; P < .001) at final follow-up. Graft surface area decreased over the follow-up period, from 24% ± 9% of the glenoid surface at early follow-up to 17% ± 10% at final follow-up (P < .001). All clinical outcome scores had improved significantly. Progression of osteoarthritis was observed in 47% of the shoulders.

Conclusion

Arthroscopically assisted posterior ICBG restored reliable parameters as shown on CT scans, especially glenoid version and the posterior subluxation indices. Graft resorption was common and could be observed in all shoulders. Patient-reported clinical outcome scores were improved. Osteoarthritis progression in almost 50% of patients is concerning for the long-term success of this procedure.

Proximal-medial part in the coracoid graft demonstrates the most evident stress shielding following the Latarjet procedure: a simulation study using the 3-dimensional finite element method

BACKGROUND

Although the osteolysis of the coracoid graft is frequently observed after the Latarjet procedure particularly in its proximal part, its pathomechanism is not well understood.

METHODS

Three-dimensional finite element glenohumeral joint models were developed using CT-DICOM data of 10 normal shoulders. A 25% bony defect was created on the anterior glenoid rim, and the coracoid process was transferred flush with the glenoid cartilage using 2 half-threaded screws. In the hanging arm as well as in the 90° abducted positions, a compressive load (50 N) was applied to the greater tuberosity toward the center of the glenoid and a tensile force (20 N) was applied to the coracoid tip along the direction of the conjoint tendon. Next, elastic analysis was performed, and the distribution patterns of the equivalent stress as well as the maximum principal stress were compared among 4 parts (proximal/distal and medial/lateral) of the coracoid graft.

RESULTS

Both the equivalent stress and the maximum principal stress were reduced in the proximal half of the coracoid graft. A high stress concentration was observed in the lateral aspect of the coracoid graft particularly in the 90° abducted position. The proximal-medial part demonstrated the lowest equivalent stress as well as the maximum principal stress for both arm positions, which were significantly lower than those in the distal 2 parts.

CONCLUSION

In the Latarjet procedure, the proximal-medial part of the coracoid graft demonstrated the most evident stress shielding, which may play an important role in postoperative osteolysis.

CT image evaluation of one-screw fixation in the Latarjet procedure

Background

In the Latarjet procedure, two screws are used for secure fixation. However, when the graft is small, two-screw fixation is technically difficult. The purpose of this study was to evaluate the bone union of one-screw fixation on CT images.

Methods

Ten shoulders with anterior recurrent dislocation underwent the open Latarjet procedure using one-screw fixation combined with arthroscopic Bankart repair. The bone union and the graft position were evaluated on CT images at 3, 6, and 12 months after the operation.

Results

Seven of 10 shoulders showed bone union at 3 months after the operation. In two shoulders, the removal of cortex was insufficient, and bone union was observed at 6 months. In one shoulder, the distal part of the graft was not in contact with the glenoid, and bone union was observed at 12 months. In one shoulder, the graft was healed in a 70-degree-rotated position. The average thickness of the graft was 7.2 ± 1.0 mm.

Conclusion

One-screw fixation in the Latarjet procedure did not show non-union. Sufficient removal of the graft cortex and good contact were needed for early union.

Early Follow-Up of Arthroscopic Latarjet Procedure with Screw or Suture-Button Fixation for Recurrent Anterior Shoulder Instability

Objective

To evaluate the early clinical and radiographic results of arthroscopic Latarjet procedure using screw or suture‐button fixation in patients with recurrent anterior shoulder dislocation.

Methods

Twelve patients who underwent arthroscopic Latarjet procedure between January 2015 and December 2018 at our institution were retrospectively studied. Data of the patients' history, including age, gender, side of affected arm, body mass index (BMI), and the number of dislocations since fist dislocation were collected. Preoperative and postoperative clinical follow‐up data were evaluated using Walch–Duplay score, American Shoulder and Elbow Society (ASES) score, and modified Rowe score. Active external rotation and active internal rotation at 90° of abduction as well as active elevation were evaluated preoperatively and postoperatively. The position and healing condition of the transferred coracoid bony graft were also assessed using computed tomography (CT) and Mimics 19.0 software.

Results

Mean follow‐up was 24.9 months (range, 13 to 53 months) of all patients. At final follow‐up, the average ASES score (preoperative vs postoperative values) had improved from 68.9 ± 7.9 to 91.1 ± 6.1 in screw fixation group and 68.9 ± 8.9 to 87.5 ± 6.7 in suture‐button fixation group; the average Rowe score (preoperative vs postoperative values) had improved from 25.0 ± 8.4 to 92.5 ± 4.2 in screw fixation group and 21.7 ± 13.7 to 93.3 ± 4.1 in suture‐button fixation group; the average of Walch–Duplay score (preoperative vs postoperative values) had improved from 12.5 ± 15.1 to 91.7 ± 4.1 in screw fixation group and 18.3 ± 20.7 to 88.3 ± 7.5 in button fixation group. The forward flexion was 175.0° ± 8.4° preoperatively and 178.3° ± 4.1° postoperatively in screw fixation group while 174.8° ± 10.2° preoperatively and 175.0° ± 5.5° postoperatively in suture‐button fixation group. The active external rotation was 77.5° ± 5.2° preoperatively and 71.7° ± 4.1° postoperatively in screw fixation group while 72.5° ± 6.9° preoperatively and 68.3° ± 7.5° postoperatively in suture‐button fixation group. The average of active internal rotation was 66.7° ± 6.1° preoperatively and 67.5° ± 6.1° postoperatively in screw fixation group while 68.3° ± 11.3° preoperatively and 66.7° ± 7.5° postoperatively in suture‐button fixation group. In postoperative CT scan, 91.7% grafts midline center were located at or under the equator in the en face view; 75% of the bone blocks were flush to the glenoid face in the axial view, with only two grafts exhibiting slight medial placement in screw fixation group (33.3%) and one graft exhibiting slight lateral placement in suture‐button fixation group (16.7%). All grafts achieved bone union. Graft absorption mostly occurred outside of the “best‐fit” circle. The average bony absorption rates of the coracoid grafts were 25.2% and 10.18% in screw fixation group and suture‐button fixation group, respectively, at 6 months postoperative follow‐up.

Conclusion

Both suture‐button fixation and screw fixation techniques in arthroscopic Latarjet procedure revealed excellent clinical outcomes with low complication rates in the early follow‐up. The suture‐button fixation exhibited a flexible fixation pattern that allowed for self‐correction to some extent, even slight lateralization could finally remodel over time.

Risk Factors for Coracoid Graft Osteolysis after the Open Latarjet Procedure

Objective  Coracoid osteolysis has been described as a possible complication after the Latarjet procedure. The aim of the present study was to investigate the incidence and risk factors associated to coracoid graft osteolysis and to correlate them with clinical results.

Methods  A retrospective review of 38 Latarjet procedures was conducted. Computed tomography (CT) scans were obtained from all of the patients before and at least 1 year after the surgery. Coracoid osteolysis was evaluated and correlated to preoperative factors, namely: age, smoking status, and preoperative glenoid bone loss. The patients were divided into 2 groups: A (no or minor bone resorption) and B (major or total bone resorption). The functional outcome was determined by the Rowe score.

Results  Coracoid graft osteolysis occurred in 22 cases (57.8%). The mean preoperative glenoid defect was 22.8% in group A, and 13.4% in group B ( p  = 0.0075). The mean ages of the subjects in both groups were not significantly different. Smoking did not seem to affect the main outcome either, and no correlation was found between graft osteolysis and postoperative range of motion, pain, or Rowe score. There were no cases of recurrent dislocations in our sample, although four patients presented with a positive anterior apprehension sign.

Conclusion  Bone resorption of the coracoid graft is present in at least 50% of the patients submitted to the Latarjet procedure, and the absence of significant preoperative glenoid bone loss showed to be the only risk factor associated with severe graft osteolysis, even though this did not influence significantly the clinical outcome.

Arthroscopic Latarjet for Shoulder Instability

Arthroscopic Latarjet is a relatively new, but viable option for the treatment of anterior shoulder instability. Arthroscopic Latarjet has the advantage of faster recovery, reduced stiffness, identification of additional shoulder pathology, and improved cosmesis when compared with open Latarjet. By the majority of clinical and radiographic parameters, arthroscopic Latarjet produces equivalent outcomes compared with open Latarjet. A relatively substantial learning curve for arthroscopic Latarjet exists at about 25 cases; however, multiple studies have demonstrated comparable outcomes and surgical time after the learning curve.

Analysis of the Anatomical Factors Associated with Cubital Tunnel Syndrome

BACKGROUND

Previous studies demonstrated that soft tissues, such as retinaculum, fibrous band, and anconeus, cause ulnar nerve compression, whereas other studies showed that the bony structures strain the ulnar nerve that runs directly behind the medial epicondyle constituting the boundary of the cubital tunnel during elbow flexion. However, no studies have reported the association of the shape of the bony structure with cubital tunnel syndrome symptoms. Are computed tomography (CT) and magnetic resonance imaging (MRI)-measured parameters of the bony cubital tunnel related to idiopathic cubital tunnel syndrome symptoms?

HYPOTHESIS

We hypothesized that CT and MRI-measured parameters of the bony cubital tunnel were related to idiopathic cubital tunnel syndrome symptoms. We aimed to investigate the relationship between the radiographic parameters based on CT and MRI and idiopathic cubital tunnel syndrome symptoms.

PATIENTS AND METHODS

We analyzed 224 elbows (77 affected elbows of patients with idiopathic cubital tunnel syndrome, 77 unaffected elbows of patients with cubital tunnel syndrome, 70 elbows of patients without cubital tunnel syndrome symptoms) using CT and MRI. Cubital tunnel cross-sectional area, cubital tunnel volume, and ulnar nerve cross-sectional area were measured in the three groups at flexion and extension. A new cubital tunnel center with a new boundary was proposed that could play a role in ulnar nerve compression symptoms.

RESULTS

The cross-sectional areas and volumes of the cubital tunnel measured in the elbow flexion state were the smallest among the group with the affected elbows in patients. There was no difference between unaffected elbows and the non-patient group. The cross-sectional area of the ulnar nerve highly correlated with cubital tunnel symptoms in the flexion state.

DISCUSSION

The shape of the cubital tunnel is an important factor in cubital tunnel syndrome, and normal variations in the volume and cross-sectional area of the cubital tunnel and ulnar nerve could influence the occurrence of idiopathic cubital tunnel syndrome.

LEVEL OF EVIDENCE

III, Therapeutic study.

Revision of failed Latarjet with the Eden-Hybinette surgical technique

INTRODUCTION

The outcomes of the Latarjet procedure for anterior shoulder instability are highly satisfactory although recurrences are possible. Surgical revision is challenging, and often requires an iliac crest bone graft as described by Eden and Hybinette. The aims of our study were to analyze the outcomes of the Eden-Hybinette technique after failed Latarjet procedure, determine the failure and complication rates, and analyze the risk of osteoarthritis. We hypothesized that the Eden-Hybinette technique would yield good outcomes after failed Latarjet procedure.

MATERIAL AND METHODS

Retrospective multicenter study (9 hospitals) by the French Shoulder and Elbow Society (SoFEC) involving 46 patients who underwent revision surgery with an Eden-Hybinette procedure after failed Latarjet stabilization. The patients had a minimum follow-up of 1year and the outcomes were evaluated based on the Rowe score, Walch-Duplay score and radiographs.

RESULTS

The mean age at the final assessment was 32years. The mean follow-up was 38 months and 86% of patients had a stable shoulder with an overall satisfaction rate of 80%. Postoperatively, the Rowe score averaged 76/100 and the Walch-Duplay score averaged 68/100; 60% of patients had resumed their sports participation. Return to sport was statistically correlated with age (p=0.0001), osteoarthritis (p=0.05) and time elapsed between the two surgical procedures (p=0.0001). The Rowe score was statistically correlated with osteoarthritis (p=0.01).

DISCUSSION/CONCLUSION

Our study is one of the largest on the Eden-Hybinette procedure for recurrent anterior shoulder instability. The outcomes at 3years' follow-up were satisfactory in 80% of patients and 86% had stable shoulders. The osteoarthritis rate was low (11%), although the follow-up period was relatively short.

LEVEL OF EVIDENCE

IV, non-randomized multicenter retrospective study.

Best implant choice for coracoid graft fixation during the Latarjet procedure depends on patients' morphometric considerations

PURPOSE

To assess the anthropometric dimensions of the coracoid process and the glenoid articular surface and to determine possible implications with the different commercially available Latarjet fixation techniques.

METHODS

In a total of 101 skeletal scapulae the glenoid length (GL), the glenoid width (GW), the coracoid length (CL), the coracoid width (CW) and the coracoid thickness (CTh) were measured. In order to assess the ability of the transferred coracoid to restore the glenoid anatomy we created a hypothetical model of 10%, 15%, 20%, 25% and 30% glenoid bone loss. We analyzed four common surgical fixation techniques for the Latarjet procedure (4.5 mm screws, 3.75 mm screws, 3.5 mm screws, and 2.8 mm button). The distances from the superior-inferior and medio-lateral limits of the coracoid using the four different fixation methods were calculated. We hypothesized that the "safe distance" between the implant and the coracoid osteotomy should be at least equal to the diameter of the implant.

RESULTS

The intra and inter-observer reliability tests were almost perfect for all measurements. The mean GH was 36.8 ± 2.5 mm, the GW 26.4 ± 2.2 mm, the CL 23.9 ± 3 mm, the CW 13.6 ± 2.mm, and the mean CTh was 8.7 ± 1.3 mm. The CL was < 25 mm in 46% of the cases. In cases with 25% and 30% bone loss, the coracoid graft restored the glenoid anatomy in 96% and 79.2% of the cases. With the use of the 4.5 mm screws the "safe distance" was present in 56% of the cases, with the 3.75 mm screws in 85%, with the 3.5 mm screws in 87%, and with the 2.8 mm button in 98% of the cases. The distance from the medio-lateral limit of the coracoid could be significantly increased (up to 9 mm) when smaller-button implants are used.

CONCLUSIONS

The coracoid graft could not always restore glenoid defects of 30%. Larger implants could be positioned too close to the osteotomy and the "medio-lateral offset" of the coracoid could be increased with smaller implants.

Validity of computed tomographic measurements and morphological comparison of cubital tunnel in idiopathic cubital tunnel syndrome

Background

Ulnar neuropathy is a common reason for referral to hand surgeons, and 10 to 30% of cubital tunnel syndrome (CuTS) is idiopathic. We hypothesized that the cause of idiopathic CuTS is in the bony structure.

Methods

We analyzed 79 elbows (39 idiopathic CuTS and 40 without CuTS symptom) using computed tomography and Materialize Mimics software to compare the differences between the two groups. We proposed a new bony cubital tunnel with a new boundary that could play a role in ulnar nerve compression symptom.

Results

The mean cubital tunnel volume was 1245.6 mm³ in all patients, 1180.6 mm³ in CuTS patients, and 1282.3 mm³ in the control group. A significant difference (p = 0.015) between two groups was found. Bony cubital tunnel cross-sectional area, cubital tunnel depth, and cubital tunnel angle also showed significant differences.

Conclusion

The shape of the bony cubital tunnel is an important cause of CuTS, and the normal variation of the volume and cross-sectional area of the cubital tunnel and cubital tunnel angle could influence the occurrence of idiopathic CuTS.

Understanding the causes behind coracoid graft osteolysıs in latarjet procedure (finite element analysis and comparison of three fixation methods)

BACKGROUND

Latarjet is one of the most common surgical procedure performed on patients with shoulder instability with osseous defects, some complications include coracoid bone graft osteolysis, osteoarthritis, graft detachment, and malpositioning were previously reported. Several studies investigated potential causes of graft osteolysis but still, it remains a crucial area of investigation. We aim to use finite element analysis to examine the potential correlations between three modes of fixation methods used in the Latarjet procedure (screw, wedge plate, and endobutton), and the coracoid graft osteolysis.

HYPOTHESIS

Finite element analysis tested the hypothesis that there is a linear relationship between the compression stress on graft which was generated by fixation methods used in the latarjet and the coracoid graft osteolysis.

MATERIAL AND METHODS

Boundary conditions and inhomogeneous material properties were carefully assigned within the material of the scapula and coracoid interface. For the screw and wedge plate fixations, an applied torque in the range of 1-1.5Nm was used to characterize the surgeon's insertion torque during the surgical operation, while a 100N compressive force was selected for the endobutton fixation.

RESULTS

Relatively lesser stress magnitudes were observed with endobutton fixation method rather than screw and the wedge plate fixation. Statistical analyses revealed significant differences between the groups (p<0.05).

DISCUSSION

Excessive compressive stresses within the coracoid graft regions may be responsible for osteolysis due to negative effects over biological factors such as blood flow. Our study emphasizes the importance of taking into account the fixation method while performing the Latarjet procedure. We concluded that the mode of fixation used within the Latarjet procedure has a correlation on the coracoid graft osteolysis.

LEVEL OF EVIDENCE

I.

Modified Arthroscopic Latarjet Procedure: Suture-Button Fixation Achieves Excellent Remodeling at 3-Year Follow-up

BACKGROUND

Some studies have advocated the use of suture-button fixation during the Latarjet procedure to reduce complications associated with screw fixation. However, the sample size of these studies is relatively small, and their follow-up period is short.

PURPOSE

To investigate the efficacy of the suture-button Latarjet procedure with at least 3 years of follow-up and remodeling of the coracoid graft.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 152 patients who underwent the suture-button Latarjet procedure between February 2013 and February 2016 were selected, and 128 patients who met the inclusion criteria were enrolled in this study. Preoperative and postoperative clinical results were assessed. The position and healing condition of the coracoid graft and arthropathy of the glenoid and humeral head were also assessed using radiography and 3-dimensional computed tomography (CT).

RESULTS

The mean follow-up time was 40.3 ± 5.8 months. There were 102 patients included in this study. The mean visual analog scale score for pain during motion, the American Shoulder and Elbow Surgeons score, the Rowe score, and the Walch-Duplay score were improved considerably. A total of 100 grafts achieved bone union. The overall absorption rate was 12.6% ± 4.3%. Graft absorption mostly occurred on the edge and outside the "best-fit" circle of the glenoid. A vertical position was achieved in 98 grafts (96% of all cases) immediately postoperatively, with the mean graft midline center at the 4 o'clock position. In the axial view, CT showed that 89 grafts were flush to the glenoid, whereas 2 and 11 grafts were fixed medially and laterally, respectively. In all cases, the bone graft and glenoid tended to extend toward each other to form concentric circles during the remodeling process. During follow-up observations, the height of the 11 grafts that were positioned laterally (ie, above the glenoid level) exhibited a wave-curved change. No arthropathy was observed in any patient.

CONCLUSION

Patient outcomes were satisfactory after the modified arthroscopic suture-button Latarjet technique. Graft absorption mostly occurred on the edge and outside the "best-fit" circle of the glenoid. The graft exhibited the phenomenon of ectatic growing when it fused with the glenoid and finally remodeled to a new concentric circle with the humeral head analogous to the original glenoid. Grafts positioned laterally did not cause arthropathy of the joints within the period of the study.

Arthroscopic Technique for Bone Augmentation With Suture Button Fixation for Anterior Shoulder Instability

Glenoid bone loss remains a significant risk factor for recurrent instability after shoulder dislocation. Several options exist for glenoid bone graft augmentation, including autograft and allograft options. Strengths and weaknesses exist for each. Graft fixation with screws remains a key concern for technical viability requiring a medial portal as well as the risk of graft osteolysis. Suture button suspensory fixation is a new technique recently described for arthroscopic iliac crest bone graft; however, no description exists concerning osteochondral graft fixation. We describe an arthroscopic technique for distal tibial allograft glenoid augmentation with suspensory suture button fixation. The rationale and technical aspects of this procedure are discussed.

Arthroscopic Latarjet: Suture-Button Fixation Is a Safe and Reliable Alternative to Screw Fixation

PURPOSE

To evaluate mid-term clinical outcomes, complications, bone-block healing, and positioning using suture-button fixation for an arthroscopic Latarjet procedure.

METHODS

Patients with traumatic recurrent anterior instability and glenoid bone loss underwent guided arthroscopic Latarjet with suture-button fixation. We included patients with anterior shoulder instability, glenoid bone loss >20%, and radiographic and clinical follow-up minimum of 24 months. Patients with glenoid bone loss <20% or those that refused computed tomography imaging were excluded. Bone-block fixation was accomplished with 2 cortical buttons connected with a looped suture (4 strands). The looped suture was tied posteriorly with a sliding-locking knot. After transfer of the bone block on the anterior neck of the scapula, compression (100 N) was obtained with the help of a tensioning device. Clinical assessment was performed at 2 weeks, 3 months, 6 months, and then yearly with computed tomography completed at 2 weeks and 6 months to confirm bony union.

RESULTS

A consecutive series of 136 patients underwent arthroscopic Latarjet with 121 patients (89%; mean age 27 years) available at final follow-up (mean follow-up, 26 months; range, 24-47 months). No neurologic complications or hardware failures were observed; no patients had secondary surgery for implant removal. The transferred coracoid process healed to the scapular neck in 95% of the cases (115/121). The bone block did not heal in 4 patients; it was fractured in 1 and lysed in another. Smoking was a risk factor associated with nonunion (P < .001). The coracoid graft was positioned flush to the glenoid face in 95% (115/121) and below the equator in 92.5% (112/121). At final follow-up, 93% had returned to sports, whereas 4 patients (3%) had a recurrence of shoulder instability. The subjective shoulder value for sports was 94 ± 3.7%. Mean Rowe and Walch-Duplay scores were 90 (range, 40-100) and 91 (range, 55-100), respectively.

CONCLUSIONS

Suture-button fixation is an alternative to screw fixation for the Latarjet procedure, obtaining predictable healing with excellent graft positioning, and avoiding hardware-related complications. There was no need for hardware removal after suture-button fixation. The systematic identification of the axillary and musculocutaneous nerves reduced risk of neurologic injury. A low instability recurrence rate and excellent return to pre-injury activity level was found. Suture-button fixation is simple, safe, and may be used for both open and arthroscopic Latarjet procedure.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Eight-Week Return to Play Following Latarjet Shoulder Reconstruction in an Australian Football Player: A Case Report

Introduction: Anterior shoulder dislocation is a common injury in many sports, resulting in extended time lost from play with an extremely high recurrence rate in young athletes playing a high-risk sport. Latarjet shoulder reconstruction is a common surgical procedure used to prevent subsequent dislocation with an expected rehabilitation time frame of between 4 and 6 months before return to play. Case Description: A 21-year-old male Australian football player experienced 2 left-sided shoulder dislocations before undergoing a left Latarjet shoulder reconstruction. He was assessed clinically and with magnetic resonance imaging, which revealed significant tearing of the anterior labrum. The authors theorized that maximal glenohumeral stability occurs after bony healing of the coracoid onto the glenoid at 6 weeks. The patient then underwent an 8-week structured and graduated rehabilitation program aimed at preventing loss of shoulder range of motion, muscle, and functional capacity and returned to play at 8 weeks postinjury with no complications or recurrence at 12-month follow-up. Discussion: This is the first time an 8-week rehabilitation following Latarjet shoulder reconstruction has been reported. In athletes with anterior glenohumeral dislocation who require accelerated return to play, a Latarjet reconstruction with an 8-week rehabilitation protocol may be considered.

Intraoperative graft-related complications are a risk factor for recurrence in arthroscopic Latarjet stabilisation

PURPOSE

The goal of this study was to evaluate clinical and radiological outcomes after arthroscopic Latarjet stabilisation in anterior shoulder instability.

METHODS

Ninety-three patients after primary arthroscopic Latarjet stabilisation were reviewed. Satisfaction, subjective shoulder value (SSV), Walch-Duplay and Rowe scores, and range of motion and stability were evaluated on clinical examination. Computed tomography (CT) was used to analyse graft position and fusion.

RESULTS

Ninety patients (96.8%) were available for clinical and 85 for CT evaluation. The mean follow-up was 23.7 months (13-50, SD 7.1) and age at surgery was 26.2 years (16-44, SD 5.6). Intraoperative complications were reported in eight patients (8.9%) and recurrence in three (3.3%). Significantly, two out of three patients with recurrence had intraoperative graft complications (p = 0.0107). Forty-one patients (45.6%) reported the feeling of "subjective return to sport anxiety". External rotation with arm at the side was 59° (10-90°, SD 20) with 15° (0-70°, SD 17) of loss of rotation. These two factors correlated with results the most. Patient satisfaction was evaluated as 92% (40-100, SD 14) and SSV 90% (30-100, SD12). Revision rate after primary surgery was 10%. CT showed graft healing in 81 (95.3%) patients. A graft position between 2 and 5 o'clock was found in 70 (83.4%) patients and flush to the anterior glenoid rim in 34 (40.5%). Osteolysis of the superior part of the graft was found in 55 (64.7%) patients. CT evaluation showed no correlation with clinical results.

CONCLUSION

Arthroscopic Latarjet stabilisation demonstrates satisfactory results in short-term follow-up; however, intraoperative graft-related complications are a risk factor for recurrence. "Subjective return to sport anxiety" and loss of external rotation with the arm at the side are factors worsening the results. Graft position imperfections and osteolysis of the superior part of the graft reported in CT evaluation do not influence the clinical results.

Arthroscopic double bone block augmentation is a salvage procedure for anterior and posterior shoulder instability secondary to glenoid bone loss

PURPOSE

The aim of this study was to describe a one-step arthroscopic anterior and posterior bone block augmentation technique for bidirectional shoulder instability and to present preliminary results.

METHODS

Seven consecutive patients who underwent a concomitant anterior and posterior bone block procedure between 2007 and 2015 were retrospectively reviewed. Clinical scores, return to sport rate, and complications were assessed. Radiological outcome, with CT scan at 6 months and plain radiographs at final follow-up were reviewed. Patient reported functional outcomes were also assessed via phone or email interview.

RESULTS

Seven consecutive patients were included in the study with a median age at surgery of 27 years. Median clinical and radiological follow-up was 7 months (4-72 months). Walch-Duplay score and Rowe scores were improved. Four patients were able to return to sport. One patient experienced recurrent dislocation, and one subjective instability/subluxation without confirmed recurrence. CT scan showed union in all cases, with one case of anterior bone block osteolysis and one case of partial posterior bone block osteolysis. Radiographs showed no detectable progression of osteoarthritis using the Samilson and Prieto classification. At final follow-up the median WOSI score was 187 (100-1140).

CONCLUSIONS

An all-arthroscopic technique for the treatment of combined anterior and posterior glenoid bone loss as a cause of shoulder instability can provide fair to good clinical outcomes, with a low incidence of intra-operative complications. The rate of failure in our series remains higher than that seen in primary stabilization procedures. As such we consider this largely as a salvage procedure for cases in which alternative treatments have failed or are unlikely to succeed.

LEVEL OF EVIDENCE

IV.

Editorial Commentary: Computed Tomography-based Analysis of the Arthroscopic Latarjet Procedure Suggests Graft Positioning Is More Variable than Expected

The Latarjet operation is one of the most successful techniques for the treatment of recurrent anterior shoulder instability, which has recently been translated into the arthroscopic field. Several studies suggest that its arthroscopic variant is safe and reproducible and report promising short-term and mid-term results. Some authors claim that, in addition to less soft tissue damage, positioning of the coracoid graft is more accurate during arthroscopic control. There is currently no evidence of superiority of the arthroscopic or the open technique. As with the open procedure, the arthroscopic Latarjet operation requires a substantial learning curve; therefore the arthroscopic technique should be reserved for experienced arthroscopists treating a large number of shoulder instabilities.

Quantitative Assessment of the Coracoacromial and the Coracoclavicular Ligaments With 3-Dimensional Mapping of the Coracoid Process Anatomy: A Cadaveric Study of Surgically Relevant Structures

PURPOSE

To perform a quantitative anatomic evaluation of the (1) coracoid process, specifically the attachment sites of the conjoint tendon, the pectoralis minor, the coracoacromial ligament (CAL), and the coracoclavicular (CC) ligaments in relation to pertinent osseous and soft tissue landmarks; (2) CC ligaments' attachments on the clavicle; and (3) CAL attachment on the acromion in relation to surgically relevant anatomic landmarks to assist in planning of the Latarjet procedure, acromioclavicular (AC) joint reconstructions, and CAL resection distances avoiding iatrogenic injury to surrounding structures.

METHODS

Ten nonpaired fresh-frozen human cadaveric shoulders (mean age 52 years, range 33-64 years) were included in this study. A 3-dimensional coordinate measuring device was used to quantify the location of pertinent bony landmarks and soft tissue attachment areas. The ligament and tendon attachment perimeters and center points on the coracoid, clavicle, and acromion were identified and subsequently dissected off the bone. Coordinates of points along the perimeters of attachment sites were used to calculate areas, whereas coordinates of center points were used to determine distances between surgically relevant attachment sites and pertinent bony landmarks.

RESULTS

The CAL had a single consistent acromial attachment (mean area 77 mm [51.9, 102.2]) and then bifurcated into 2 bundles, anterior and posterior, that separately inserted on the lateral aspect of the coracoid. The footprint areas were 54.4 mm² [31.7, 77.2] and 30.6 mm² [23.4, 37.7] for the anterior and posterior CAL bundles, respectively. These anterior and posterior bundles attached 10.6 mm [8.4, 12.9] and 24.8 mm [12.3, 27.4] medial and proximal to the apex of the coracoid process, respectively. The minimum distance between the coracoid apex and the trapezoid ligament was 25.1 mm [22.1, 28.1] and was noted to be different in males (28.1 mm [25.1; 31.2]) and females (22.0 mm [18.2, 25.9]). The most lateral insertion of the CC ligaments on the clavicle the AC joint was 15.7 mm [13.1, 18.3]. The distance between the most medial to the most lateral point of the CC ligaments on the clavicle was 25.6 mm [22.3, 28.9], which accounted for 18.2% [15.8, 20.6] of the clavicle length.

CONCLUSIONS

In contrast to previous findings, 2 different coracoid attachments (anterior and posterior bundles) of the CAL were consistently identified in all specimens. Moreover, a coracoid osteotomy for a bone graft for the Latarjet procedure should be performed at less than 28.1/22 mm from the apex of the coracoid in male/female patients, respectively. The CC ligaments' attachments on the clavicle were located 15.7 mm from the AC joint, which should be considered for reconstruction.

CLINICAL RELEVANCE

During the Latarjet technique, to maintain the integrity of the CC ligaments, precise knowledge of differences between male and female anatomy is necessary during a coracoid osteotomy. Furthermore, when reconstructing the AC joint, the distance from the lateral aspect of the clavicle and the size of the attachments areas should be considered to better replicate the native anatomy.

A Prognostic Nomogram for Postoperative Bone Remodeling in Patients with ADDWoR

This study aimed to establish an effective prognostic nomogram for predicting the probability of postoperative bone remodeling of patients with anterior disc displacement without reduction (ADDWoR). The nomogram was based on a retrospective study on patients underwent surgical approaches for ADDWoR at Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University from January, 2007 to January, 2017. A multivariate logistic regression analysis was used to develop variables suitable for probability estimation model. The predictive accuracy and discriminative ability were determined by ROC (AUC-index) and calibration curve. Results were validated using bootstrap resampling with all statistical tests two-sided. 1110 patients were included in the analysis. The probability of postoperative bone remodeling in ADDWoR was 0.51. Six independent prognostic factors including age of onset, nocturnal bruxism, disc morphology, BMD, Wilkes’ classification, and postoperative splint therapy were integrated to construct the nomogram. The probability estimation model showed good discrimination in both internal and external validation with AUC-index of 0.84. The calibration curves for probability of postoperative bone remodeling showed optimal agreement with actual observation. In conclusion, a nomogram was established to provide individual prediction of postoperative bone remodeling for patients with ADDWoR treated by arthroscopy surgery.

Fate of coracoid grafts after the Latarjet procedure: will be analogous to the original glenoid by remodelling

PURPOSE

To evaluate the location, magnitude, and change over time of osteolysis of coracoid grafts after Latarjet procedure.

METHODS

This is a retrospective study of 54 patients (55 shoulders) who underwent the Latarjet procedure. Three-dimensional computed tomography (CT) scans were performed preoperatively, immediately postoperatively, and at follow-up (mean 7.7 and 31.7 months postoperative). "En face" views of the glenoid, size of glenoid defect and changes in the glenoid surface area postoperatively were measured relative to the area of an assumed outer-fitting circle. On the oblique sagittal planes, location and subsequent severity of osteolysis of the graft at follow-up were documented.

RESULTS

The mean glenoid surface area increased significantly from 79.7 ± 4.8% of the original circle preoperatively to 111.3 ± 8.0% immediately postoperatively. At 7.7 and 31.7 months of follow-up, glenoid surface area decreased to 102.2 ± 6.0% and 100.3 ± 5.3%, respectively. Osteolysis occurred on the outer side of the graft in all cases, but did not occur on the inner side. Maximum osteolysis was observed in the superior third of the graft (78.5 ± 17.1%), followed by the middle third (15.8 ± 10.4%), and the inferior third (8.0 ± 5.1%). No significant difference in magnitude of osteolysis was observed between 7.7 and 31.7 months of follow-up.

CONCLUSION

Osteolysis of the grafted coracoid mainly occurred on the outer side of the superior portion, resulting in reshaping of the rectangular shape of graft coracoids after Latarjet procedure. Coracoid graft remodelling was almost completed approximately 8 months postoperatively to reach the original glenoid dish with no further changes thereafter. These results may help surgeons to understand changes of grafts after the surgery.

LEVEL OF EVIDENCE

IV.

Review of Latarjet (1954) on the treatment of recurrent shoulder dislocations

This classic discusses the original publication ‘Treatment of recurrent dislocation of the shoulder’ on the Latarjet procedure. This surgical technique that has become one of the basics in shoulder-stabilising surgery, introduced by Latarjet in 1954 in the journal Lyon Chirurgical. Inspired by publications of colleagues in the field of shoulder surgery, Latarjet introduced a technique that transfers the coracoid process to the anterior glenoid rim in patients with anterior shoulder instability. Although being outrun in popularity by the Bankart repair for several decades, improved knowledge regarding long-term outcomes, surgical techniques and patient characteristics such as bone loss and participation in contact sports has led to renewed interest in the Latarjet procedure. This especially accounts for patients with significant glenohumeral bone loss or patients with a previously failed soft tissue repairs. Whereas the increase in popularity has led to many studies focussing on various aspects, the 15 basics of the initial procedure have virtually remained unchanged.

Does the Arthroscopic Latarjet Procedure Effectively Correct "Off-Track" Hill-Sachs Lesions?

BACKGROUND

The glenoid track concept describes the dynamic interaction of bipolar bone loss in anterior glenohumeral instability. Initial studies have successfully demonstrated this concept's application in clinical populations. In clinical practice, the Latarjet procedure is commonly the preferred treatment in addressing "off-track" Hill-Sachs lesions. The effectiveness of this procedure in restoring such lesions to an "on-track" state, however, has not yet been evaluated or described in the literature.

HYPOTHESIS

The Latarjet procedure would transform "off-track" Hill-Sachs lesions to "on-track" lesions. Lesions would remain "on-track" during follow-up, despite glenoid remodeling.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients with "off-track" Hill-Sachs lesions treated with the arthroscopic Latarjet procedure between March 2013 and May 2014 were included. Glenoid track and coracoid graft contact surface area measurements using 3-dimensional computed tomography (3D-CT) were performed preoperatively and at 6-week, 6-month, and at least 12-month (final) follow-up. The mean final follow-up was 23 months. The glenoid diameter, as a percentage of the native glenoid, was also calculated from this imaging.

RESULTS

Twenty-six patients met the inclusion criteria. 3D-CT scans were available for all patients preoperatively and postoperatively, with 21 patients (81%) undergoing 6-month follow-up CT and 19 patients (73%) undergoing final follow-up CT. Hill-Sachs lesions remained "on-track" at all follow-up time points. The mean glenoid diameter changed significantly from 84.6% preoperatively to 122.8% at 6 weeks ( P < .001) and from 120.5% at 6 months to 113.9% at final follow-up ( P = .005). This was also reflected in significant remodeling seen in the coracoid graft articular contact area (6 weeks to 6 months, P = .024; 6 months to final follow-up, P = .002). This persisting glenoid arc enlargement at final follow-up avoided "off-track" Hill-Sachs lesions in 6 of 19 patients (32%), which would otherwise have occurred had the coracoid graft remodeled to native glenoid dimensions.

CONCLUSION

The Latarjet procedure provides an effective treatment for "off-track" engaging Hill-Sachs lesions, despite an evident glenoid remodeling process. At a mean of 23 months postoperatively, a mean persisting enlargement of the glenoid arc of 14% beyond native dimensions remained, avoiding a recurrent "off-track" lesion in 32% of patients, which would otherwise have occurred with complete remodeling.

Editorial Commentary: The Wake of the Dragon: Will the Orthopaedic Community Adopt the Shoulder Arthroscopic Latarjet Procedure as We Adopted the Arthroscopic Rotator Cuff Repair?

The Latarjet procedure is a complex and difficult operation when performed both with an open approach and arthroscopically. The difficulties come from the fact that it is a combined intra- and extra-articular procedure, and that working close to the brachial plexus may be frightening for surgeons. Because of the high complication and reoperation rates reported in the literature, this procedure is, at the moment, rejected by a large part of the orthopaedic community, specifically in North America. The Chinese experience shows, after the European one, that arthroscopic Latarjet is an efficient and irreplaceable option for the treatment of recurrent anterior shoulder instability in the context of capsular and/or glenoid deficiency. A recent study shows that the arthroscopic procedure provides accurate bone block positioning and high rates of healing, excellent clinical results (no recurrence of instability at 2-year follow-up), and low rates of complications (no neurovascular injury). Although the arthroscopic Latarjet should be approached with caution, the learning curve should not be thought of as prohibitive. To learn how to perform an arthroscopic Latarjet, surgeons should visit an experienced surgeon and take a course to practice on cadavers first. Although it will take time and effort to learn and perform this operation correctly, we should command our Chinese colleagues to encourage us to follow their path. There is no reason that in the near future the orthopaedic community does not adopt the arthroscopic Latarjet procedure, as we adopted the arthroscopic rotator cuff repair and other complex surgical procedures. Among the strongest reasons to perform the Latarjet procedure arthroscopically are the accuracy of graft placement, the safety for neurovascular structures provided by direct visualization and magnification, and the excellent clinical results allowing young people to go back to sport, including high-risk (contact, overhead) sports.

Is the two-dimensional computed tomography scan analysis reliable for coracoid graft positioning in Latarjet procedures?

BACKGROUND

The aim of the study was to develop a computed tomography (CT)-based measurement protocol for coracoid graft (CG) placement in both axial and sagittal planes after a Latarjet procedure and to test its intraobserver and interobserver reliability.

METHODS

Fifteen postoperative CT scans were included to assess the intraobserver and interobserver reproducibility of a standardized protocol among 3 senior and 3 junior shoulder surgeons. The evaluation sequence included CG positioning, its contact area with the glenoid, and the angle of its screws in the axial plane. The percentage of CG positioned under the glenoid equator was also analyzed in the sagittal plane. The intraobserver and interobserver agreement was measured by the intraclass correlation coefficient (ICC), and the values were interpreted according to the Landis and Koch classification.

RESULTS

The ICC was substantial to almost perfect for intraobserver agreement and fair to almost perfect for interobserver agreement in measuring the angle of screws in the axial plane. The intraobserver agreement was slight to almost perfect and the interobserver agreement slight to substantial regarding CG positioning in the same plane. The intraobserver agreement and interobserver agreement were both fair to almost perfect concerning the contact area. The ICC was moderate to almost perfect for intraobserver agreement and slight to almost perfect for interobserver agreement in analyzing the percentage of CG under the glenoid equator.

CONCLUSION

The variability of ICC values observed implies that caution should be taken in interpreting results regarding the CG position on 2-dimensional CT scans. This discrepancy is mainly explained by the difficulty in orienting the glenoid in the sagittal plane before any other parameter is measured.