Recurrent Glenohumeral Instability Research Articles

Characterization of articular lesions associated with glenohumeral instability using arthroscopy.

The prevalence of osteoarthritis (OA) associated with instability of the shoulder ranges between 4% and 60%. Articular cartilage is, however, routinely assessed in these patients using radiographs or scans (2D or 3D), with little opportunity to record early signs of cartilage damage. The aim of this study was to assess the prevalence and localization of chondral lesions and synovial damage in patients undergoing arthroscopic surgery for instablility of the shoulder, in order to classify them and to identify risk factors for the development of glenohumeral OA. A total of 140 shoulders in 140 patients with a mean age of 28.5 years (15 to 55), who underwent arthroscopic treatment for recurrent glenohumeral instability, were included. The prevalence and distribution of chondral lesions and synovial damage were analyzed and graded into stages according to the division of the humeral head and glenoid into quadrants. The following factors that might affect the prevalence and severity of chondral damage were recorded: sex, dominance, age, age at the time of the first dislocation, number of dislocations, time between the first dislocation and surgery, preoperative sporting activity, Beighton score, type of instability, and joint laxity. A total of 133 patients (95%) had synovial or chondral lesions. At the time of surgery, shoulders were graded as having mild, moderate, and severe OA in 55 (39.2%), 72 (51.4%), and six (4.2%) patients, respectively. A Hill-Sachs lesion and fibrillation affecting the anteroinferior glenoid cartilage were the most common findings. There was a significant positive correlation between the the severity of the development of glenohumeral OA and the patient's age, their age at the time of the first dislocation, and the number of dislocations (p = 0.004, p = 0.011, and p = 0.031, respectively). Synovial inflammation and chondral damage associated with instability of the shoulder are more prevalent than previously reported. The classification using quadrants gives surgeons more information about the chondral damage, and could explain the pattern of development of glenohumeral OA after stabilization of the shoulder. As the number of dislocations showed a positive correlation with the development of OA, this might be an argument for early stabilization.

Clinical outcomes of open Latarjet-Patte procedures performed for recurrent anterior shoulder instability with primary bone loss versus failed arthroscopic Bankart repair.

This study compares the outcomes of Latarjet-Patte procedures (LPs) performed for primary glenohumeral instability in the setting of critical bone loss (LP-BL) versus salvage surgery performed after a failed arthroscopic Bankart repair (LP-FB). LP's performed by senior author from 2017 to 2021 were separated into cohorts by LP indication. Data abstracted from electronic medical records included demographic information, preoperative clinical scores, radiological imaging, and complications. Postoperative clinical outcome scores collected after a 2-year minimum follow-up included: patient-reported outcomes measurement information system (PROMIS) upper extremity (UE), PROMIS pain interference, PROMIS pain intensity, American Shoulder and Elbow Surgeons (ASES), and visual analog scale pain scores. A total of 47 patients (LP-BL: n=29, LP-FB: n=18) with a mean age of 29 years (range, 15-58 years) were included in this study. Both cohorts achieved good upper extremity functionality without significant differences as indicated by mean PROMIS UE (LP-BL: 52.6±10.0 vs. LP-FB: 54.6±7.6, P=0.442) and ASES score (LP-BL: 89.9±15.7 vs. LP-FB: 91.5±14.4, P=0.712). However, the LP-FB cohort reported lower levels of pain (LP-FB: 0.5±1.1 vs. LP-BL: 1.9±2.7, P=0.020) at their latest follow-up. There were no significant differences in complication rates including re-dislocation between cohorts (LP-BL: 2/29 [6.9%] vs. LP-FB: 2/18 [11.1%], P=0.629). When performed after failed Bankart repair, the LP results in similar postoperative functional outcomes and similar rates of complications and re-dislocations when compared to the primary indication of recurrent glenohumeral instability in the setting of critical bone loss. Level of evidence: III.

Arthroscopic Shoulder Stabilization in High School Football Players.

Destabilizing shoulder injuries are common in high school American football players; however, the rate of recurrent glenohumeral instability and return to play after arthroscopic labral stabilization surgery remains unknown. The purpose of this study was to determine the rate of recurrent instability on return to competitive high school football after arthroscopic shoulder labral stabilization and capsulorrhaphy procedures. It was hypothesized that the instability rate would be greater in players with more years of eligibility remaining (YER) to play at the high school level. Case series; Level of evidence, 4. Consecutive male high school football players with at least 1 YER who sustained at least 1 anterior traumatic inseason shoulder instability episode and underwent arthroscopic stabilization between 2012 and 2017 were identified. Patients and/or families were contacted by phone to discuss (1) recurrent instability episodes and (2) return to competitive sport and/or recreational athletic activity. Statistical analysis was conducted using chi-square tests to compare recurrent shoulder instability with return to play and YER. A total of 45 football players aged 14 to 17 years were included, with a mean follow-up of 4.1 years. Most patients (60%) chose not to return to competitive football, due mainly to fear of recurrent injury. Overall, the recurrent instability rate was 15.6% (7/45). The instability rate in players who returned to football was 16.7%, with 66.7% requiring revision surgery. The instability rate in patients who did not return to football was 14.8%, with no revision procedures required. In players who returned to football, the instability rate in YER group 4 was significantly higher than that in YER groups 1 to 3 (42% vs 10.5%, respectively, P = .03), with each year of play conferring an additional 10% risk of reinjury. There was a significant difference in the type of recurrent instability in players who returned to any sport versus those who did not (P = .029). High school football players who returned to competitive play after arthroscopic shoulder stabilization surgery experienced a higher rate of recurrent instability that was dependent on their YER. Over half of the players chose not to return to football, with fear of reinjury being the most common reason.

The Effect of Concavity Restoration on Glenohumeral Stability in a Glenoid Bone Loss Model: Comparing the Distal Tibial Allograft Reconstruction and the Latarjet Procedure

Objectives: Glenoid bone loss occurs in more than 80% of patients with recurrent glenohumeral instability. The Latarjet procedure has become the gold standard for restoration of bone loss despite a high (15-30%) complication rate.1–3 Distal tibial allograft (DTA) reconstruction has recently gained interest due to its ability to restore width and concavity to the glenoid while providing a cartilage surface.4 The purpose of this study is to evaluate the restoration of glenohumeral anterior stability and glenoid concavity after DTA reconstruction when compared to the Latarjet procedure in a glenoid bone loss model. Methods: Five human cadaveric specimens (mean age: 62.2, range 57-69; 80% male) underwent preoperative computed tomography (CT) scans to assess native glenoid concavity as determined by the glenoid depth and bony shoulder stability ratio (BSSR). Stability testing was performed using a cadaveric shoulder simulator that allows 6 DoF at the glenohumeral joint. The specimens were placed with the scapula at 30° upward rotation and humerus at 60° glenohumeral abduction with a constant compressive force created by loading the supraspinatus, infraspinatus, teres minor, and subscapularis muscles (2lbs, 3lbs, 1lb and 4lbs respectively). A Kuka robot applied a 40N anterior force through the pectoralis tendon with the humerus in neutral as well as 60 degrees of external rotation. A motion capture system recorded humeral head translations for each condition. To create the Latarjet and DTA conditions, the coracoid was first harvested and the thickness was measured. A distal tibial allograft was then contoured to an identical size. A glenoid defect was created to match the thickness of the graft since both Latarjet and DTA aimed for a 100% glenoid restoration.. The following conditions were tested: 1. intact, 2. Bankart lesion, 3. bone loss model with DTA reconstruction, 4. Latarjet procedure without the conjoint tendon loaded, and 5. Latarjet with conjoint tendon loading (‘sling effect’). All specimens underwent post-testing CT scan to measure the BSSR of the DTA and Latarjet reconstructions. A repeated measures ANOVA was performed to determine if there was a significant difference in maximum anterior translation or BSSR between the distal tibial allograft reconstruction and Latarjet procedure (with or without the sling effect). Results: The mean preoperative glenoid depth measured 2.61±1.03mm with a BSSR of 0.40±0.16. However, postoperative measurements showed that BSSR for the DTA was greater than the Latarjet (0.46±0.11 vs 0.35±0.5). The maximum anterior translation was significantly lower after the DTA reconstruction than the Latarjet procedure without the sling effect (5.5mm vs 9.6mm, p = 0.044). However, there was no difference in anterior translation between the DTA reconstruction and Latarjet procedure with the sling effect applied (5.5mm vs 4.7mm, p = 0.36). The DTA reconstructed the glenoid with a significantly greater concavity than the Latarjet procedure (BSSR: 0.46 vs 0.35, p = 0.036). Conclusions: When addressing bone loss in glenohumeral instability, additional factors besides the restoration of glenoid width contribute to stability. The concave reconstruction produced by the distal tibial allograft decreases anterior translation compared to the flat reconstruction produced by the Latarjet, but there is no difference in translation between the DTA and Latarjet procedure when the sling effect is applied. The DTA reconstruction provides an alternative to the Latarjet procedure with equivalent biomechanical properties and less morbidity or change to the native shoulder structure.

The moment arms and lines of action of subscapularis after the Latarjet procedure.

The Latarjet procedure is an established surgical treatment for recurrent glenohumeral joint instability with glenoid bone loss. Intraoperatively, the conjoint tendon and its attachement on the coracoid bone graft is routedthrough a split in subscapularis where the graft is fixed to and augments the anteroinferior glenoid. The objective of this in vitro study was to quantify the influence of glenohumeral joint position and conjoint tendon force on the lines of action and moment arms of subscapularis muscle sub-regions after Latarjet surgery. Eight fresh-frozen, entire upper extremities were mounted onto a testing apparatus, and a cable-pulley system was used to apply physiological muscle loading to the major shoulder muscles. The lines of action and moment arms of four subregions of subscapularis (superior, mid-superior, mid-inferior, and inferior) were quantified radiographically with the conjoint tendon unloaded and loaded while the shoulder was in (i) 0° abduction (ii) 90° abduction (iii) 90° abduction and full external rotation (ABER), and (iv) the apprehension position, defined as ABER with 30° horizontal extension. Conjoint tendon loading after Latarjet surgery significantly increased the inferior inclination of the lines of action of the mid-inferior and inferior subregions of subscapularis in the scapular plane in ABER and apprehension positions (p < 0.001), as well as decreased the horizontal flexion moment arm of the inferior subscapularis (p = 0.040). Increased subscapularis inferior inclination may ultimately increase inferior joint shear potential, while smaller horizontal flexion leverage may reduce joint flexion capacity. The findings have implications for Latarjet surgical planning and postoperative rehabilitation prescription.

Arthroscopic Remplissage for Anterior Shoulder Instability

Background: There are several approaches such as the Bankart repair, Latarjet, and Remplissage to treat recurrent glenohumeral instability. Indications: We chose to augment an arthroscopic Bankart repair with a Remplissage in this 26-year-old patient given the presence of a Hill-Sachs lesion, history of recurrent shoulder dislocations, and young age of the patient. Technique Description: We established four portals using previously well-documented techniques. The Hill-Sachs lesion was evaluated using the anterosuperior portal. Two anchors were placed, one on both the superior and inferior aspects of the Hill-Sachs lesion. The sutures were shuttled through the knotless anchor mechanism and tensioned after confirming the cannula was through the deltoid. Then, we completed the Remplissage by repairing the infraspinatus tendon and capsule into the posterior humeral head. Results: The Remplissage procedure is very successful at reducing recurrent instability in young, active patients. Previous studies have reported very low rates, even 0% recurrent instability, after surgery with 80% to 90% of patients returning to sports. Studies have also documented excellent patient-reported outcomes at short- to mid-term follow-up. Complication rates are historically lower when the Remplissage is done with an arthroscopic Bankart repair than the Bankart repair alone. Discussion/Conclusion: The Remplissage procedure is a safe, effective option at reducing future instances of shoulder dislocations in conjunction with Bankart repairs. Patients can expect to return to their active lifestyles, with many patients achieving the same level of activity as before the initial shoulder dislocation. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Criteria-based return to sport testing after open Latarjet reveals residual deficits and can be utilized for sports clearance with excellent outcomes at mean 3.6 year follow-up: A small case series of competitive athletes

ObjectiveThe purpose of this study was to assess the use of a criteria-based return to sport (CBRTS) test to evaluate readiness for return to play (RTP) in competitive athletes that underwent open Latarjet. DesignRetrospective case series. MethodsTen competitive athletes (mean age 19.9 years) treated with open Latarjet for recurrent glenohumeral instability underwent CBRTS testing at a mean of 5.3 months postoperatively. Testing consisted of four components: 1. isometric strength, 2. isokinetic strength, 3. endurance, and 4. function. Patients failing 0 or 1 component of the test were cleared to RTP. Patients failing multiple components underwent additional deficit-based rehabilitation. ResultsOf the 10 patients that tested, 4 passed their overall CBRTS test and were cleared to RTP. The remaining 6 patients failed the overall CBRTS test. Seven patients (70%) failed at least one section of the strength testing, two patients (20%) failed endurance testing, and two patients (20%) failed functional testing. At final follow-up (mean 3.6 years), 1 patient had recurrent instability (10%) and 9 patients returned to play (90%). ConclusionsCBRTS testing may be clinically useful for return to play clearance decisions after open Latarjet procedure, as it can reveal deficits that may not be identified with time-based clearance alone.

Trends and projections in surgical stabilization of glenohumeral instability in the United States from 2009 to 2030: rise of the Latarjet procedure and fall of open Bankart repair.

Advances in surgical techniques have improved the ability to address recurrent glenohumeral instability via arthroscopic capsulolabral repair and bone-restoring procedures such as the Latarjet procedure. Given the paucity of studies analyzing temporal trends in the surgical management of glenohumeral instability, the purpose of this study was to assess trends in the treatment of anterior, posterior, and multidirectional instability over a 10-year period and model projections to 2030. Using the IBM Watson MarketScan national database, we identified all patients who underwent glenohumeral instability procedures from 2009 to 2018. Procedures were identified using Current Procedural Terminology codes for open Bankart, Latarjet, anterior bone block, posterior bone block, multidirectional capsular shift, and arthroscopic Bankart procedures. Sample weights provided by the database were used to calculate national estimates. US Census Bureau annual population data were used to calculate incidence. Future projections to 2030 were modeled using Poisson and linear regression. There were an estimated 446,072 glenohumeral instability cases from 2009 to 2018. The per capita incidence (per 100,000) remained constant, from 14.8 in 2009 to 14.5 in 2018. Arthroscopic Bankart procedures comprised the highest number of procedures throughout the study period, accounting for 89% of all procedures in 2009 and 93% in 2018. The number of open Bankart procedures decreased by 65% from 2009 to 2018, whereas the number of Latarjet procedures showed a 250% increase over the same period. Patient demographics did not change over the study period, and male patients aged 18-25 years comprised the largest demographic group undergoing anterior instability procedures. Multidirectional instability procedures exhibited the least pronounced sex differences. Future modeling from 2018 to 2030 projected a continued steady rise in arthroscopic Bankart procedures (from 40,000 to 49,000 cases/yr), rapid growth in Latarjet procedures (from 1370 to 4300 cases/yr), and continued decline in open Bankart procedures (from 1000 to 250 cases/yr). Arthroscopic Bankart repair continues to be the most common glenohumeral instability procedure in the United States. From 2009 to 2018, the incidence of open Bankart procedures declined whereas the incidence of Latarjet procedures markedly increased. Future projections to 2030 mirrored these findings. These data may provide an enhanced understanding of the evolution of surgical treatment of glenohumeral instability within the United States, laying the foundation for continued prospective studies into the appropriate indications and advancements in surgical techniques.

Poster 166: Distal Clavicle versus Traditional and Congruent Arc Latarjet: Comparison of Surface Area and Glenoid Apposition with 3-Dimensional CT and MRI

Objectives: Limited studies have compared graft-glenoid apposition and glenoid augmentation area between the latarjet and distal clavicle grafts in glenohumeral stabilization. Additionally, pre-operative planning is typically performed using computerized tomography (CT), and few studies have used 3- dimensional magnetic resonance imaging (3D-MRI) reformations to assess graft dimensions. The purpose of the study was two-fold: 1) compare bony apposition, glenoid augmentation, and graft width among coracoid and distal clavicle bone augmentation techniques and 2) to determine the viability of 3D-MRI to assess bone graft dimensions. Methods: Twenty-four patients with recurrent glenohumeral instability and bone loss were included in this study. 3D-CT and 3D-MRI reformations were utilized to measure pertinent dimensions for five orientations of coracoid and distal clavicle autografts: (1) standard Latarjet (SLJ), (2) congruent arc Latarjet (CLJ), and (3) distal clavicle attached by its posterior surface, (DCP) and (4) inferior surface (DCI), and (5) resected end (DCR). Glenoid augment area was defined as the graft surface area contributing to the glenoid. Bone-on-bone apposition was defined as the graft-glenoid contact area for bone healing potential, and graft width was pertinent for fixation technique. Paired t-tests were performed to compare graft sizes between patients and compare 3D-CT vs 3D-MRI measurements. Results: CLJ had the largest glenoid augmentation area (mean: 318mm2, sd: 74) while SLJ displayed the most apposition (mean: 318mm2, sd: 74). DCI had the largest graft width (mean: 21mm, sd: 4). Paired t- tests revealed no significant differences between Latarjet methods, whereas distal clavicle grafts varied significantly with orientation. All 3D-CT and 3D-MRI measurements were within 1mm of each other, and only two demonstrated statistically significant difference (coracoid width: 13.03 vs 13.98mm, p=0.010; distal clavicle thickness: 9.69 vs 10.77, p=0.002). 3D-CT and 3D-MRI measurements demonstrated strong positive correlation (r&gt;0.6 and p&lt;0.001 for all dimensions). Conclusions: Glenoid augmentation, bony apposition, and graft width can vary with coracoid or distal clavicle graft type and orientation. Differences between 3D-CT and 3D-MRI were small and likely not clinically significant.

Paper 02: Distal Radius Allograft for Glenohumeral Instability: A Novel Osteochondral Allograft Reconstruction Option in the Setting of Glenoid Bone Loss

Objectives: Glenoid bone loss in the setting of recurrent shoulder instability remains a challenging surgical problem. The coracoid process and iliac crest currently serve as primary autograft options for glenoid reconstruction. With regards to allograft alternatives, the distal tibia, first described in 2007, has good midterm outcomes when used during an index surgery and in cases of failed prior Latarjet reconstruction. While the distal tibia performs well in reconstructing the glenoid bony defect, it is a nonanatomic reconstruction and does not match the glenoid radius of curvature (ROC) in the anterior to posterior (AP) plane. No prior work has evaluated and described the utilization of the dorsal articular portion of the distal radius as an allograft reconstruction option for recurrent instability with glenoid bony deficiency. The purpose of this study was to evaluate distal radius fresh frozen allograft as a potential match for glenoid reconstruction through assessment of graft ROC and bone mineral density (BMD). Distal tibia allograft was utilized as the primary comparison group with both cadaveric and Computerized Tomography (CT) analysis. Methods: Eighteen fresh-frozen human cadaveric specimens (6 shoulder, 6 wrist, and 6 tibia) were utilized for this study. Specimens without osteoarthritis or prior surgical procedures were included. CT scans were obtained of all specimens to confirm the absence of osteoarthritis, significant joint deformity, or evidence of prior surgical procedure. Specimens were dissected free of all soft tissues except for the glenoid labrum of the shoulder and dorsal wrist ligaments of the distal radius. The ROC for each specimen were independently measured by two fellowship trained shoulder surgeons in both the superior to inferior (SI) and AP planes. Graft length in the SI plane was also assessed. A thirty percent defect was then created in all glenoid specimens and both distal tibia and distal radius grafts were harvested to assess graft fit post-fixation [Figure 1]. CTs were also analyzed to assess bony ROC and BMD for each specimen. Results: On cadaveric analysis, the mean SI graft length of the glenoid was 39.7 mm compared to 36.8 mm for the distal radius and 30.0 mm for the distal tibia [Table 1A]. Average ROC in the SI plane was 29.0 +/- 5.3 for the glenoid, 37.8 +/- 4.9 for the distal radius and 24.0 +/- 3.7 for the distal tibia; in the AP plan average ROC was 39.6 +/- 6.6 for the glenoid, 30.4 +/- 18.6 for the distal radius and 126.3 +/- 9.5 for the distal tibia [Table 1B]. On CT analysis, average ROC in the SI plane was 30.4 +/- 1.5 for the glenoid, 30.3 +/- 5.6 for the distal radius and 24.5 +/- 9.4 for the distal tibia; in the AP plane average ROC was 30.8 +/- 2.0 for the glenoid, 19.1 +/- 2.3 for the distal radius and 46.7 +/- 21.7 for the distal tibia [Table 2A]. Mean BMD was 226.3 +/- 79.0 for the glenoid, 228.5 +/-94.7 for the distal radius, 235.0 +/- 96.2 for the coracoid process, and 235.1 +/- 84.6 for the distal tibia [Table 2B]. Conclusions: Given fresh frozen allograft supply and cost constraints, exploration of additional graft options is necessitated. This study presents distal radius allograft as a novel reconstruction option for patients with anterior glenoid bone loss in the setting of recurrent glenohumeral instability. Compared with the distal tibia allograft, the distal radius had greater graft length in the SI plane providing possible utilization in cases of larger bony defects. The distal radius also has a more acute ROC in the AP plane (closer to that of the glenoid) compared with the distal tibia allograft providing a greater potential buttress to anterior humeral translation. Furthermore, the distal radius also has potential to employ the dorsal radio-carpal ligaments to perform an anterior capsular repair following allograft fixation. Finally, compared to currently utilized grafts (coracoid process and distal tibia), the distal radius BMD was not significantly diminished on CT analysis. This study presents the distal radius as a novel allograft reconstruction option in the setting of glenoid bone loss; further biomechanical and clinical investigation is indicated. [Table: see text][Table: see text]

A Bibliometric Analysis of the Most Cited Research on Humeral Avulsions of the Glenohumeral Ligament: A Paucity of High-Level Evidence

To identify the 25 most-cited articles on humeral avulsion of the glenohumeral ligament (HAGL) lesions and characterize them based on number of citations, citation density, source journal, year of publication, geographic origin, article type, and level of evidence. The Science Citation Index Expanded database was queried for all possible publications regarding HAGL lesions. The 25 most-cited articles from 1976 to 2021 relevant to the topic were selected for further analysis. Articles were characterized based on the number of citations, citation density, year of publication, source journal, country of origin, article type, article subtype, and level of evidence. The number of citations for individual articles ranged from 21 to 182 (mean ± standard deviation: 44.72 ± 36.87). Ten countries contributed to the 25 most cited articles, with 14 of the 25 (56%) articles published in the United States. Furthermore, the top 25 cited articles were published in 9 journals, with the majority in Arthroscopy-The Journal of Arthroscopic and Related Surgery (n= 15, 60%). There were 15 (60%) articles classified as "Clinical," 9 (36%) as "Review/Expert Opinion," and 1 (4%) as "Basic Science." All clinical studies met the standard for level IV evidence. This bibliometric analysis provides a list of the 25 most cited articles related to HAGL lesions, providing a reference of impactful articles for medical educators. The lack of high level of evidence "Clinical" studies demonstrates that higher-quality research is needed to establish guidelines for the treatment and management of HAGL lesions. A list of the 25 most-cited articles regarding recurrent glenohumeral instability can serve as a comprehensive reference for practitioners, educators, researchers, and orthopaedic trainees.

Distal Clavicle Autograft Versus Traditional and Congruent Arc Latarjet Procedures: A Comparison of Surface Area and Glenoid Apposition With 3-Dimensional Computed Tomography and 3-Dimensional Magnetic Resonance Imaging

Background: Limited studies have compared graft-glenoid apposition and glenoid augmentation area between the Latarjet procedure and distal clavicle graft in glenohumeral stabilization. Additionally, preoperative planning is typically performed using computed tomography (CT), and few studies have used 3-dimensional (3D) magnetic resonance imaging (MRI) reformations to assess graft dimensions. Purpose: The purpose of this study was 2-fold: (1) to compare bony apposition, glenoid augmentation, and graft width among coracoid and distal clavicle bony augmentation techniques and (2) to determine the viability of 3D MRI to assess bone graft dimensions. Study Design: Controlled laboratory study. Methods: A total of 24 patients with recurrent glenohumeral instability and bone loss were included in this study. 3D CT and 3D MRI reformations were utilized to measure pertinent dimensions for 5 orientations of coracoid and distal clavicle autografts: (1) standard Latarjet procedure (SLJ), (2) congruent arc Latarjet procedure (CLJ), (3) distal clavicle attached by its posterior surface (DCP), (4) distal clavicle attached by its inferior surface (DCI), and (5) distal clavicle attached by its resected end (DCR). Glenoid augmentation was defined as the graft surface area contributing to the glenoid. Bone-on-bone apposition was defined as the graft-glenoid contact area for bone healing potential, and graft width was pertinent for fixation technique. Glenoid bone loss ranged from 0% to 34%. Paired t tests were used to compare graft sizes between patients and compare 3D CT versus 3D MRI measurements. Results: The CLJ had the largest graft surface area (mean, 318.41 ± 74.44 mm2), while the SLJ displayed the most bone-on-bone apposition (mean, 318.41 ± 74.44 mm2). The DCI had the largest graft width (mean, 20.62 ± 3.93 mm). Paired t tests revealed no significant differences between the Latarjet techniques, whereas distal clavicle grafts varied significantly with orientation. All 3D CT and 3D MRI measurements were within 1 mm of each other, and only 2 demonstrated a statistically significant difference (coracoid width: 13.03 vs 13.98 mm, respectively [P = .010]; distal clavicle thickness: 9.69 vs 10.77 mm, respectively [P = .002]). 3D CT and 3D MRI measurements demonstrated a strong positive correlation (r > 0.6 and P < .001 for all dimensions). Conclusion: Glenoid augmentation, bony apposition, and graft width varied with coracoid or distal clavicle graft type and orientation. Differences between 3D CT and 3D MRI were small and likely not clinically significant. Clinical Relevance: 3D MRI is a viable method for preoperative planning and graft selection in glenoid bone loss.

Dynamic Anterior Stabilization Using Transosseous Bone Tunnel Technique With the Adjustable Loop Length Cortical Button Incorporating High-Strength Suture Augmentation for Recurrent Shoulder Instability

Dynamic anterior stabilization using the long head of the biceps tendon is a recently described technique in the management of recurrent shoulder dislocation with subcritical bone loss. This technique involves the transfer of the long head of the biceps to the glenoid, providing sling and hammock effect. The long head of the biceps (LHB) tendon fixation can be accomplished with a variety of implants. We present a modified fixation technique of LHB tendon using transosseous bone tunnel with the adjustable loop length cortical button, incorporating high-strength suture augmentation device in a patient with recurrent glenohumeral instability with limited glenoid bone loss and an engaging Hill-Sachs defect in the humeral head.

Functional biomechanical comparison of Latarjet vs. distal tibial osteochondral allograft for anterior glenoid defect reconstruction

Glenoid reconstruction is indicated for recurrent glenohumeral instability with significant glenoid bone deficiency. Coracoid autograft (Latarjet) and distal tibial osteochondral allograft (DTA) reconstructions have been used to successfully restore glenohumeral stability. Relative advantages and disadvantages associated with each reconstruction technique have been described. However, direct comparisons of functional glenohumeral biomechanics associated with Latarjet vs. DTA reconstruction are lacking. This study was designed to compare these 2 glenoid reconstruction techniques with respect to joint kinematics and cartilage pressure mapping using a robotic testing system. In accordance with institutional review board policies, human cadaveric shoulders (n=8) were cyclically tested in the neutral position and 90° of external rotation with 60° and 90° of abduction under a 45-N joint-compression load to measure clinically relevanttranslations, loads, and torques. Joint contact pressure maps were obtained under a 120-N joint-compression load using pressure mapping sensors. After confirming that a 25% anterior glenoid defect resulted in glenohumeral dislocation, testing was performed to compare 3 conditions: native intact glenoid, 25% anterior glenoid defect with Latarjet reconstruction, and 25% anterior glenoid defect with DTA reconstruction. Analyses of variance and t tests were used to analyze data with statistical significance set at P< .05. Significant differences in anterior translation, inferior drawer, anterior drawer, compression loads, horizontal abduction, negative elevation (adduction), and external rotation torques during cyclical testing in 90° of external rotation with 60° and/or 90° of abduction were noted when comparing the 2 different glenoid bone reconstruction techniques to native, intact shoulders. The only significant difference between Latarjet and DTA reconstructions for measured translations, loads, and torques was a significantly higher absolute maximum compressive load for Latarjet compared to DTA at 60° of abduction. Latarjet coracoid osseous autograft and distal tibial osteochondral allograft reconstructions of large (25%) glenoid bone defects prevent failure (dislocation) and are associated with significant glenohumeral kinematic differences that largely confer less translation, load, and torque on the joint in abduction when compared to the native state. These findings suggest that these 2 surgical techniques exhibit similar glenohumeral kinematics such that each provides adequate functional stability following anterior glenoid bone reconstruction. Joint compression load and articular contact pressure distribution may favor distal tibial osteochondral allograft reconstruction for treatment of large (25%) anterior glenoid bone defects associated with shoulder instability.

Recurrence of glenohumeral instability in patients with isolated rotator cuff repair after a traumatic shoulder dislocation.

The primary objective of this study was to assess the incidence of recurrent glenohumeral instability in patients over 40years with isolated rotator cuff (RC) repair for traumatic shoulder dislocation. The secondary objectives were to identify risk factors for glenohumeral recurrence after RC repair and to describe the causes and incidences of re-intervention. In this retrospective cohort study, data of consecutive patients at a single trauma center between January 2014 and July 2019 were reviewed, and 84 patients with a mean age of 57 (range: 40-75) years and follow-up duration of 3.9 (2-6) years were included. The inclusion criteria were as follows: first traumatic anterior shoulder dislocation, reparable RC tear, primary arthroscopic RC repair, no labral or bony Bankart lesion repair, and at least 2years of follow-up. Patients less than 40years of age were excluded. Shoulder instability recurrences and surgical reinterventions were reviewed with medical records. Statistical analysis was performed for qualitative variables using the Chi-squared test. Statistical significance was set at P ≤ 0.05. There was one patient with a redislocation episode (1.2%) at 2.5years after surgery, who was surgically treated. Age, subscapular tears, bony Bankart injuries, humeral defects, and associated neurological injuries were not risk factors for recurrence in this study. Ten patients (11.9%) required reintervention. Nine patients (10.7%) re-tore their RCs. Recurrent glenohumeral instability in active patients over 40years with isolated RC repair after traumatic shoulder dislocation was infrequent, despite the incidence of significant Hill-Sachs defects, anterior glenoid defects, bipolar bone defects, size of the RC injury, and tendon re-tears. The incidence of re-interventions was 11.9%, with symptomatic RC retear as the main cause.

The Glenoid Track Concept: On-Track and Off-Track—A Narrative Review

Shoulder instability is described as a functional deficiency caused by excessive mobility of the humeral head over the glenoid. Various Glenohumeral Instability (GI) types have been described, but the traumatic anteroinferior form is the most frequent. The differences between engaging and non-engaging Hill–Sachs lesions (HSLs) are linked to bone loss assessment. On the contrary, the novel difference between “on-track” and “off-track” lesions is strictly related to surgical techniques. The specific involvement of glenoid and humerus bone defects in recurrent GI was poorly assessed in the literature before the glenoid-track concept (GT). Magnetic Resonance Imaging (MRI) and Arthro-MRI have been widely used to identify and characterize lesions to the ligamentous structures. However, only new technologies (3 Tesla MRI) accurately detect HSLs. On the contrary, Computed Tomography (CT) has been adopted to quantify glenoid bone deficit. The GT concept is a valuable tool for evaluating anterior shoulder instability in patients. Shoulders out of alignment may require more than just an arthroscopic Bankart, and a remplissage or bone transfer may be necessary. Specifically, isolated Bankart repair should be considered in patients with recurrent instability and an on-track lesion with less than 25% glenoid bone loss. In off-track lesions and less than 25% glenoid bone loss, remplissage should be used. Bone transplant surgery is required for patients with a glenoid bone defect of more than 25%. This narrative review aims to report the most updated findings on “on-track” and “off-track” lesions in GI.

Glenoid Bone Loss Directly Affects Hill-Sachs Morphology: An Advanced 3-Dimensional Analysis

Background: While the glenoid track concept presents a useful prediction for recurrent glenohumeral instability, little is known about the humeral head bony architecture as it relates to glenoid erosion in the setting of bipolar bone loss. Purpose: To (1) qualitatively and quantitatively analyze the interplay between glenoid bone loss (GBL) and Hill-Sachs lesions (HSLs) in a cohort of patients with anterior instability using 3-dimensional imaging software and (2) assess the relationships between GBL and HSL characteristics. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Patients were identified who had anterior shoulder instability with a minimum 5% GBL and evidence of HSL confirmed on computed tomography. Unilateral 3-dimensional models of the ipsilateral proximal humeral head and en face sagittal oblique view of the glenoid were reconstructed using MIMICS software (Materialise NV). GBL surface area, width, defect length, and glenoid track width were quantified. The volume, surface area, width, and depth of identified HSLs were quantified with their location (medial, superior, and inferior extent) on the humeral head. Severity of GBL was defined as percentage glenoid bone surface area loss and categorized as low grade (5%-10%), moderate grade (>10% to 20%), high grade (>20% to 30%), and extensive (>30%). Analysis of variance was then computed to determine significance (P < .05) between severity of GBL and associated HSL parameters. Results: In total, 100 patients met inclusion criteria (mean age, 27.9 years; range, 18-43 years), which included 58 right shoulders and 42 left shoulders (84 male, 16 female). Among groups, there were 32 patients with low-grade GBL (mean GBL = 6.1%), 38 with moderate grade (mean GBL = 16.2%), 17 with high grade (mean GBL = 23.7%), and 13 with extensive (mean GBL = 34.0%), with an overall mean GBL of 18.1% (range, 5%-39%). Patients with 5%-10% GBL had significantly narrower HSLs (average and maximum width; P < .03) and deeper HSLs (average depth; P = .002) as compared with all other GBL groups, while greater GBL was associated with wider and shallower HSLs. GBL width, percentage width loss, defect length, and glenoid track width all significantly differed across the 4 GBL groups (P < .05). Conclusion: HSLs had significantly different morphological characteristics depending on the severity of GBL, indicating that GBL was directly related to the characteristics of HSLs. Patients presenting with smaller glenoid defects had significantly narrower and deeper HSLs with less humeral head surface area loss, while greater GBL was associated with wider and shallower HSLs.

Patient Factors Associated With Increased Risk for Complications After the Latarjet Procedure.

Background:The open Latarjet has become the most common method of addressing significant glenoid bone loss in patients with recurrent glenohumeral instability.Purpose:To describe national trends in Latarjet procedures and risk factors for complications associated with this procedure.Study Design:Cohort study; Level of evidence, 3.Methods:Eligible patients were identified through the National Surgical Quality Improvement Program (NSQIP) data set over the years 2014 to 2018 by using the Current Procedural Terminology (CPT) code for “capsulorrhaphy anterior with coracoid process transfer” (CPT 23462). Patient and surgical outcome variables were extracted and analyzed from the NSQIP database. Logistic regression analysis and odds ratios (ORs) were performed to evaluate the relative risk of complications.Results:The authors identified 458 patients (399 men and 59 women) from the data set. The mean body mass index was 27.4 kg/m2, and mean operative time was 130.2 minutes. Statistically significant variables included smoking status and sex, which were further stratified. Smokers were 2.19 times more likely to experience at least 1 adverse outcome, including deep vein thrombosis (DVT), pulmonary embolism, reoperation, wound infection, unplanned readmission, or readmission (95% CI, 0.62-7.82). Specifically, smokers were 7.8 times more likely to have a DVT (95% CI, 0.58-105.96), 1.4 times more likely to undergo reoperation (95% CI, 0.14-5.73), and 2.4 times more likely to have an unplanned readmission (95% CI, 0.19-28.68). Women were 2.2 times more likely to experience at least 1 adverse outcome. Specifically, women were found to be 6.4 times more likely to have a DVT (95% CI, 0.76-54.87), 4.1 times more likely to have an unplanned readmission (95% CI, 0.00-106.21), and 4.7 times more likely to have a readmission (95% CI, 0.00-13.92).Conclusion:The results indicate that smokers and female patients are at a higher risk of experiencing adverse outcomes and may require additional pre- and postprocedural precautions when undergoing the Latarjet procedure. With the increase in frequency, providers should be aware of patient-related factors that may lead to adverse outcomes.

Modified Dynamic Anterior Stabilization (DAS) and Hill-Sachs Remplissage for the Treatment of Recurrent Anterior Shoulder Dislocation

The optimal treatment for recurrent glenohumeral instability is a subject under debate. The recently described arthroscopic technique for dynamic anterior stabilization (DAS) fills the treatment indication gap between reconstructive bony procedures and soft tissue stabilization. However, indications for DAS are considered limited or not appropriate for patients with recurrent shoulder dislocations caused by severe bone defects. In this Technical Note, we present a modified all-arthroscopic DAS technique with added infraspinatus and posterior capsule remplissage to correct the extra-articular Hill-Sachs defect in a patient with recurrent dislocations and off-track bony lesions. The patient requested an alternative treatment option, other than the complication-prone Latarjet procedure.

Anterior Glenoid Reconstruction With Distal Tibial Allograft: Biomechanical Impact of Fixation and Presence of a Retained Lateral Cortex.

Background:Glenoid reconstruction with distal tibial allograft (DTA) is a known surgical option for treating recurrent glenohumeral instability with anterior glenoid bone loss; however, biomechanical analysis has yet to determine how graft variability and fixation options alter the torque of screw insertion and load to failure.Hypothesis:It was hypothesized that retention of the lateral cortex of the DTA graft and the presence of a washer with the screw will significantly increase the maximum screw placement torque as well as the load to failure.Study Design:Controlled laboratory study.Methods:Whole, fresh distal tibias were used to harvest 28 DTA grafts, half of which had the lateral cortex removed and half of which had the lateral cortex intact. The grafts were secured to polyurethane solid foam blocks with a 2-mm epoxy laminate to simulate a glenoid with an intact posterior glenoid cortex. Grafts underwent fixation with 4.0-mm cannulated drills, and screws and washers were used for half of each group of grafts while screws alone were used for the other half, creating 4 equal groups of 7 samples each. A digital torque-measuring screwdriver recorded peak torque for screw insertion. Constructs were then tested in compression with a uniaxial materials testing system and loaded in displacement control at 100 mm/min until at least 3 mm of displacement occurred. Ultimate load was defined as the load sustained at clinical failure.Results:The use of a washer significantly improved the ultimate torque that could be applied to the screws (+cortex and +washer = 12.42 N·m [SE, 0.82]; –cortex and +washer = 10.54 N·m [SE, 0.59]) (P < .0001), whereas the presence of the native bone cortex did not have a significant effect (+cortex and –washer = 7.83 N·m [SE, 0.40]; –cortex and –washer = 8.03 N·m [SE, 0.56]) (P = .181).Conclusion:In a hybrid construct of fresh cadaveric DTA grafts secured to a foam block glenoid model, the addition of washers was more effective than the retention of the lateral distal tibial cortex for both load to failure and peak torque during screw insertion.Clinical Relevance:This biomechanical study is relevant to the surgeon when choosing a graft and selecting fixation options during glenoid reconstruction with a DTA graft.