Editorial Commentary: Both 3-Dimensional Magnetic Resonance Imaging and Computed Tomography Are Valuable for Determination of Glenoid and Humeral Bone Loss in Patients With On- and Off-Track Shoulder Instability.

Improving the modalities for advanced glenohumeral joint imaging has been an important area to address in the field of orthopaedic surgery. The current gold standard for imaging glenoid and humeral bone loss in patients with shoulder instability, 3-dimensional (3D) computed tomography (CT), provides high-quality 3D images of bones but comes with a cost of extra time, additional imaging because of the need for an additional magnetic resonance imaging (MRI) scan, and exposure to radiation. Three-dimensional MRI is a promising solution that can produce high-contrast images depicting both bony structures and soft tissues. Multiple 3D MRI sequences have been studied, with the FRACTURE (fast field echo resembling a CT using restricted echo-spacing) sequence showing high comparability of bony measurements to 3D CT scans, as well as the ability for widespread clinical use. Recent research has shown minimal differences in 3D CT and 3D MRI and has confirmed that 3D imaging does provide clinically relevant data for determination of on- and off-track instability. Finally, the gold standard for determination of bone loss is the measurement of deficiencies in the surface area of the glenoid using the best-fit circle with a diameter line measurement. This is most practical for day-to-day clinical use.

Even With a High Retear Rate, Shoulder Capsular Reconstruction Outcomes are Promising, But Are We Seeing an Increase in Strength?

Superior capsular reconstruction was developed to restore patient biomechanics for patients with massive irreparable rotator cuff tears that preclude shoulder arthroplasty. Recent studies have shown excellent short-term clinical outcomes and improved pain and functional scores but high rates of complications including retear, loss of fixation, or incomplete healing. An alternative option, reverse total shoulder arthroplasty, is a reliable and safe method to ensure good muscle strength and return to play in this patient group.

Postoperative Radiographic Outcomes Following Primary Open Coracoid Transfer (Bristow-Latarjet) Vary in Definition, Classification, and Imaging Modality: A Systematic Review.

PURPOSE: To analyze radiographic outcomes by conventional radiography, computed tomography (CT), or both and complication rates of open coracoid transfer at a minimum of 12-months follow-up. METHODS: A literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using PubMed, Medline (Ovid), and EMBASE library databases. Inclusion criteria were clinical studies reporting on open Latarjet as the primary surgical procedure(revision coracoid transfer after failed prior stabilization excluded) with postoperative radiographic outcomes at a minimum mean 1-year follow-up. Patient demographics, type of postoperative imaging modality, and radiographic outcomes and complications including graft union, osteoarthritis, and osteolysis were systematically reviewed. Data were summarized as ranges of reported values for each outcome metric. Each radiographic outcome was graphically represented in a Forest plot with point estimates of the incidence of radiographic outcomes with corresponding 95% confidence intervals and I2. RESULTS: Thirty-three studies met inclusion criteria, with a total of 1,456 shoulders. The most common postoperative imaging modality was plain radiography only (n = 848 [58.2%]), both CT and radiography (n = 287 [19.7%]), and CT only (n = 321 [22.1%]). Overall, the reported graft union rate ranged from 75% to 100%, of which 79.8% (n = 395) were detected on plain radiography. The most common reported postoperative radiographic complications after the open coracoid transfer were osteoarthritis (range, 0%-100%, pooled mean 28%), graft osteolysis (range, 0%-100%, pooled mean 30%), nonunion (range, 0%-32%, pooled mean 5.1%), malpositioned graft (range, 0%-75%, pooled mean 14.75%), hardware issues (range, 0%-9.1%, pooled mean 5%), and bone block fracture (range, 0%-8%, pooled mean 2.1%). Graft healing was achieved in a majority of cases (range, 75%-100%). CONCLUSION: Postoperative radiographic outcomes after open coracoid transfer vary greatly in definition, classification, and imaging modality of choice. Greater consistency in postoperative radiographic outcomes is essential to evaluate graft healing, osteolysis, and nonunion. LEVEL OF EVIDENCE: Level IV, systematic review of Level III-IV studies.

Outcomes of total shoulder arthroplasty in patients with prior anterior shoulder instability: minimum 5-year follow-up.

BACKGROUND: Patients with a history of anterior shoulder instability (ASI) commonly progress to glenohumeral arthritis or even dislocation arthropathy and often require total shoulder arthroplasty (TSA). The purposes of this study were to (1) report patient-reported outcomes (PROs) after TSA in patients with a history of ASI, (2) compare TSA outcomes of patients whose ASI was managed operatively vs. nonoperatively, and (3) report PROs of TSA in patients who previously underwent arthroscopic vs. open ASI management. METHODS: Patients were included if they had a history of ASI and had undergone TSA ≥5 years earlier, performed by a single surgeon, between October 2005 and January 2017. The exclusion criteria included prior rotator cuff repair, hemiarthroplasty, or glenohumeral joint infection before the index TSA procedure. Patients were separated into 2 groups: those whose ASI was previously operatively managed and those whose ASI was treated nonoperatively. This was a retrospective review of prospective collected data. Data collected was demographic, surgical and subjective. The PROs used were the American Shoulder and Elbow Surgeons score, Single Assessment Numerical Evaluation score, QuickDASH (Quick Disabilities of the Arm, Shoulder and Hand) score, and 12-item Short Form physical component score. Failure was defined as revision TSA surgery, conversion to reverse TSA, or prosthetic joint infection. Kaplan-Meier survivorship analysis was performed. RESULTS: This study included 36 patients (27 men and 9 women) with a mean age of 56.4 years (range, 18.8-72.2 years). Patients in the operative ASI group were younger than those in the nonoperative ASI group (50.6 years vs. 64.0 years, P < .001). Operative ASI patients underwent 10 open and 11 arthroscopic anterior stabilization surgical procedures prior to TSA (mean, 2 procedures; range, 1-4 procedures). TSA failure occurred in 6 of 21 patients with operative ASI (28.6%), whereas no failures occurred in the nonoperative ASI group (P = .03). Follow-up was obtained in 28 of 30 eligible patients (93%) at an average of 7.45 years (range, 5.0-13.6 years). In the collective cohort, the American Shoulder and Elbow Surgeons score, Single Assessment Numerical Evaluation score, QuickDASH (Quick Disabilities of the Arm, Shoulder and Hand) score, and 12-item Short Form physical component score significantly improved, with no differences in the postoperative PROs between the 2 groups. We found no significant differences when comparing PROs between prior open and prior arthroscopic ASI procedures or when comparing the number of prior ASI procedures. Kaplan-Meier analysis demonstrated a 79% 5-year survivorship rate in patients with prior ASI surgery and a 100% survivorship rate in nonoperatively managed ASI patients (P = .030). CONCLUSION: At mid-term follow-up, patients with a history of ASI undergoing TSA can expect continued improvement in function compared with preoperative values. However, TSA survivorship is decreased in patients with a history of ASI surgery compared with those without prior surgery.

Editorial Commentary: Hyperlaxity Is a Common Factor in Failed Arthroscopic Bankart Repair.

Hyperlaxity is a common factor in failed arthroscopic Bankart repair. The best treatment for patients with instability, hyperlaxity, and minimal bone loss is still controversial. Patients with hyperlaxity often have subluxations rather than frank dislocation, and concurrent traumatic structural lesions are infrequent. Conventional arthroscopic Bankart repair with or without capsular shift poses a risk of recurrence because of soft tissue insufficiency. The Latarjet is not a good procedure in patients with hyperlaxity and instability, especially an inferior component, and risks include a higher degree of postoperative osteolysis after Latarjet with an intact glenoid. The arthroscopic Trillat procedure may be used to treat this challenging patient group by repositioning the coracoid medially and downward by a partial wedge osteotomy. The coracohumeral distance and shoulder arch angle are decreased after performing the Trillat, which may reduce instability, and the Trillat procedure mimics the sling effect of the Latarjet. However, complications should be considered due to the procedure's nonanatomic nature, such as osteoarthritis, subcoracoid impingement, and loss of motion. Other options to improve inferior stability include robust rotator interval closure, coracohumeral ligament reconstruction, and posteroinferior/inferior/anteroinferior capsular shift. The addition of posteroinferior capsular shift and rotator interval closure in the medial lateral direction also benefits this vulnerable patient group.

Survival of anterior cruciate ligament reconstructions in active-duty military populations.

PURPOSE: Anterior cruciate ligament tears and anterior cruciate ligament reconstruction (ACLR) are common in young athletes. The modifiable and non-modifiable factors contributing to ACLR failure and reoperation are incompletely understood. The purpose of this study was to determine ACLR failure rates in a physically high-demand population and identify the patient-specific risk factors, including prolonged time between diagnosis and surgical correction, that portend failure. METHODS: A consecutive series of military service members with ACLR with and without concomitant procedures (meniscus [M] and/or cartilage [C]) done at military facilities between 2008 and 2011 was completed via the Military Health System Data Repository. This was a consecutive series of patients without a history of knee surgery for two years prior to the primary ACLR. Kaplan-Meier survival curves were estimated and evaluated with Wilcoxon test. Cox proportional hazard models calculated hazard ratios (HR) with 95% confidence intervals (95% CI) to identify demographic and surgical factors that influenced ACLR failure. RESULTS: Of the 2735 primary ACLRs included in the study, 484/2,735 (18%) experienced ACLR failure within four years, including (261/2,735) (10%) undergoing revision ACLR and (224/2,735) (8%) due to medical separation. The factors that increased failure include Army Service (HR 2.19, 95% CI 1.67, 2.87), > 180 days from injury to ACLR (HR 1.550, 95% CI 1.157, 2.076), tobacco use (HR 1.429 95% CI 1.174, 1.738), and younger patient age (HR 1.024, 95% CI 1.004, 1.044). CONCLUSION: The overall clinical failure rate of service members with ACLR is 17.7% with minimum four-year follow-up, where more patients are likely to fail due to revision surgery than medical separation. The cumulative probability of survival at 4 years was 78.5%. Smoking cessation and treating ACLR patients promptly are modifiable risk factors impacting either graft failure or medical separation. LEVEL OF EVIDENCE: Level III.

The Effect of Buttress Plating on Biomechanical Stability of Coronal Shear Fractures of the Capitellum: A Cadaveric Study.

PURPOSE: The purpose of this study was to compare, using a cadaveric model, the biomechanical properties of headless compression screws (HCSs) and HCSs augmented with a buttress plate (BP) in capitellar fractures. METHODS: Twenty pairs of fresh-frozen humeri (mean age, 46.3 years; range, 33-58 years) were used. The soft tissue was removed, and a Dubberley type IA capitellar fracture was created. One specimen in each pair was randomly assigned to receive either two 2.5-mm HCSs (HCS group) or two 2.5-mm HCSs augmented with an anterior 2.4-mm BP (HCS + BP group). This resulted in a similar distribution of the left and right humeri between the groups. Cyclic loading was performed, and displacement of the capitellum at 50, 100, 250, 500, 1,000, and 2,000 cycles was assessed using a motion capture system. This was followed by load-to-failure testing, wherein the load at a displacement of 1 and 2 mm was recorded. Failure was defined as 2-mm displacement. RESULTS: During cyclic loading, there were no significant differences in the displacement between the HCS and HCS + BP groups at any of the assessed cycles. During load-to-failure testing, no significant strength differences were observed in the load at 1-mm displacement between the HCS (mean: 449.8 N, 95% CI: 283.6-616.0) and HCS + BP groups (mean: 606.2 N, 95% CI: 476.4-736.0). However, a significantly smaller load resulted in a 2-mm displacement of the fragment in the HCS group (mean: 668.8 N, 95% CI: 414.3-923.2) compared with the HCS + BP group (mean: 977.5 N, 95% CI: 794.1-1,161.0). CONCLUSIONS: Anterior, low-profile buttress plating in addition to HCSs results in a significantly higher load to failure compared with HCSs alone in a biomechanical Dubberley type IA capitellar fracture model. CLINICAL RELEVANCE: The addition of an anterior BP may be considered to improve initial stability in select cases such as osteoporotic patients or when the posterolateral column is frail.

Editorial Commentary: Posterior Shoulder Instability Surgical Treatment Outcomes Are Inferior to Outcomes of Anterior Instability: Standardization of Patient Evaluation and Indications Could Improve Results.

Arthroscopic capsulolabral repair remains the mainstay of treatment in patients with refractory shoulder posterior instability. In addition, glenoid bone block augmentation procedures for posterior shoulder instability are gaining momentum. Unfortunately, results from anterior glenoid bone block augmentation procedures have enjoyed much better success than posterior, and it is unclear why surgical treatment of posterior instability with either congenital or acquired retroversion, with or without posterior bone loss, can result in complications or poor outcomes. It is essential to standardize evaluation and reporting of clinical presentation, radiographic assessment, indications, and mid- to long-term follow-up in patients who undergo posterior shoulder bony augmentation procedures. Current literature suggests that greater than 11% posterior glenoid bone loss increases risk of surgical failure 10 times, and 15% posterior bone loss increases risk of surgical failure 25 times, suggesting a possible threshold for posterior bony augmentation. However, in the end, the problem is complex, and work remains to better define optimal patient indications in consideration of congenital or acquired pathology, retroversion, amount of bone loss, and patient demographics and risk factors.

Management of Complex and Revision Anterior Shoulder Instability.

Treatment of recurrent anterior shoulder instability has gained significant interest in recent years and involves evaluation of both glenoid and humeral sided bone loss. Decision making is more complex in patients with significant humeral or glenoid bone defects or in those who underwent previous instability surgery. Appropriate assessment of the glenoid track is necessary as "off track" lesions typically require treatments beyond arthroscopic labral repair alone. In those with significant humeral or glenoid sided bone loss, the authors recommend three-dimensional computed tomography in addition to magnetic resonance imaging for accurate evaluation. The Glenoid Track Instability Management Score is a useful guide to help direct treatment by using the glenoid track as well as other known risk factors for recurrence. In circumstances with significant glenoid bone loss, typically over 20%, a coracoid transfer such as the Latarjet is recommended. In patients that previously failed a coracoid transfer, the authors recommend a distal tibia allograft; however, distal clavicle and iliac crest autograft have also been reported to have high success rates. In those with large Hill-Sachs lesions, remplissage or bone grafting are recommended. An estimation of the postoperative glenoid track after glenoid bone augmentation is required for appropriate Hill-Sachs lesion treatment. The authors typically recommend against revision instability surgical treatment with arthroscopic repair alone.

Shoulder Latarjet Surgery Shows Wide Variation in Reported Indications, Techniques, Perioperative Treatment, and Definition of Outcomes, Complications, and Failure: A Systematic Review.

PURPOSE: To systematically review and compare the surgical indications, technique, perioperative treatment, outcomes measures, and how recurrence of instability was reported and defined after coracoid transfer procedures. METHODS: A systematic review of the literature examining open coracoid transfer outcomes was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using the Cochrane registry, MEDLINE, and EMBASE databases from 2010 to 2020. Inclusion criteria included open coracoid transfer techniques, including the Bristow or Latarjet technique, full text availability, human studies, and English language. RESULTS: A screen of 1,096 coracoid transfer studies yielded 72 studies, which met inclusion criteria with a total of 4,312 shoulders. One study was a randomized controlled trial, but the majority of them were retrospective. Of those, 65 studies reported on postoperative outcome scores, complication rates, revision rate, and recurrence rates. Forty-three reported on range of motion results. Thirty studies reported on primary coracoid transfer only, 7 on revision only, and 30 on both primary and revision, with 5 not reporting. Average follow-up was 26.9 months (range: 1-316.8 months). Indications for coracoid transfer, technique, perioperative care, complications, and how failure was reported varied greatly among studies. CONCLUSIONS: Latarjet and coracoid transfer surgery varies greatly in its indications, technique, and postoperative care. Further, there is great variation in reporting of complications, as well as recurrence and failure and how it is defined. Although coracoid transfer is a successful treatment with a long history, greater consistency regarding these factors is essential for appropriate patient education and surgeon knowledge. LEVEL OF EVIDENCE: Level IV, systematic review of Level I-IV studies.

High rate of return to sport and excellent patient-reported outcomes after an open Latarjet procedure.

HYPOTHESIS: The purpose of this study was to report return to sport, patient-reported outcomes (PROs), subjective outcomes, and complications or failures in patients who underwent open Latarjet surgery. METHODS: Patients who underwent open Latarjet surgery performed by 2 fellowship-trained surgeons between August 2006 and November 2018 were included. Prospectively collected data were reviewed. Recurrent instability and revision surgical procedures were recorded. Subjective outcomes included return to sport and fear of reinjury or activity modification as a result of patients' instability history. PROs included the American Shoulder and Elbow Surgeons (ASES) score, Short Form 12 Physical Component Summary score, Single Assessment Numeric Evaluation score, Quick Disabilities of the Arm, Shoulder and Hand score, and satisfaction. Age, sex, sports participation, pain, primary vs. revision surgery (prior failed arthroscopic or open Bankart repair), dislocation number, glenoid bone loss, glenoid track concept, and projected glenoid track were evaluated. Failure was defined as an ASES score <70, recurrent dislocation, or revision instability surgery. RESULTS: A total of 126 shoulders (125 patients) met the inclusion criteria, with a mean age of 28.1 years (range, 15-57 years). Of 126 shoulders, 7 (5.5%) underwent additional procedures prior to final follow-up and were excluded from outcome analyses; failure occurred in 6 of these shoulders. Mean follow-up data at 3.7 years (range, 2-9.3 years) were attained in 86.6% of patients (103 of 119). All PROs significantly improved from preoperative baseline (ASES score, from 69.7 to 90.2; Single Assessment Numeric Evaluation score, from 55.8 to 85.9; and Quick Disabilities of the Arm, Shoulder and Hand score, from 28.4 to 10.5). PROs did not differ based on sex, sports participation type, dislocation with or without sports, primary vs. revision procedure, and preoperative dislocation number. No correlations existed between PROs and age, glenoid bone loss, or number of previous surgical procedures. On-track lesions (50 of 105, 47.6%) and projected on-track lesions (90 of 105, 85.7%) correlated with better patient satisfaction but not PROs. Despite not having recurrences, 63 of 99 patients (63.6%) reported activity modifications and 44 of 99 patients (44.4%) feared reinjury. These groups had statistically worse PROs, although the minimal clinically important difference was not met. Return to sport was reported by 97% of patients (86 of 89), with 74% (66 of 89) returning at the same level or slightly below the preinjury level. Revision stabilization surgery was required 6 of 126 cases (4.8%), and 6 of 103 shoulders (5.8%) had ASES scores <70. CONCLUSION: The open Latarjet procedure led to significant improvements in all PROs, and overall, 97% of patients returned to sport. Fear of reinjury and activity modifications were common after open Latarjet procedures but did not appear to affect clinical outcomes. On-track and projected on-track measurements correlated with better patient satisfaction but not improved PROs.

Anatomic safe zones for arthroscopic snapping scapula surgery: quantitative anatomy of the superomedial scapula and associated neurovascular structures and the effects of arm positioning on safety.

BACKGROUND: Neurovascular anatomy has not been previously quantified for the arthroscopic snapping scapula approach with the patient in the most frequent patient position ("chicken-wing" position). The purposes of this study were (1) to determine anatomic relationships of the superomedial scapula and neurovascular structures at risk during arthroscopic surgical treatment of snapping scapula syndrome (SSS), (2) to compare these measurements between the arm in the neutral position and the arm in the chicken-wing position, and (3) to establish safe zones for arthroscopic treatment of SSS. METHODS: Eight fresh-frozen cadaveric hemi-torsos (mean age, 55.8 years; range, 52-66 years) were dissected to ascertain relevant anatomic structure locations including the (1) spinal accessory nerve, (2) dorsal scapular nerve, and (3) suprascapular nerve. A coordinate measuring device was used to collect data on the relationships of anatomic landmarks and at-risk structures during the surgical approach. RESULTS: The dorsal scapular nerve was a mean of 24.4 mm medial to the superomedial scapula in the neutral position and 33.1 mm medial in the chicken-wing position (P < .001); the dorsal scapular nerve was 21.7 mm medial to the medial border of the scapular spine in the neutral position and 35.5 mm medial in the chicken-wing position (P < .001). The mean distance from the superomedial angle to the spinal accessory nerve intersection at the superior scapular border was 16.5 mm in the neutral position and 15.0 mm in the chicken-wing position (P = .031). The average distance from the superomedial angle to the closest point of the spinal accessory nerve was 11.6 mm and 10.4 mm in the neutral position and chicken-wing position, respectively (P = .039). CONCLUSION: Neurologic structures around the scapula vary significantly between the neutral arm position and the chicken-wing position commonly used in the arthroscopic treatment of SSS. The chicken-wing position improves safe distances for the dorsal scapular nerve during medial-portal placement and should be considered as a primary position for arthroscopic management of SSS.

Editorial Commentary: Preoperative 3-Dimensional Imaging for Shoulder Instability Is Vital for Determination of Off-Track Lesions and May Indicate Bankart Repair Plus Remplissage.

The on- and off-track concept is gaining momentum for surgeons who treat patients with anterior shoulder instability. Preoperative imaging is critical for improving our outcomes. Determination of an off-track lesion prior to surgery using 3-dimensional computed tomography allows for improvement in outcomes by indicating remplissage. Intraoperative determination with the patient under anesthesia is not as good or as accurate. However, although Bankart repair plus remplissage shows good outcomes, bony procedures such as Latarjet, distal tibia allograft, and iliac crest or other bone graft procedures are preferred for large defects. Still, perhaps it is time to truly look at posterior adjuncts to anterior instability such as remplissage in patients who have off-track lesions, even with notable bipolar bone loss.

Editorial Commentary: What Is More Important: Strength or Displacement? Findings of All-Suture Anchor Versus Interference Screw for Biceps Tenodesis.

Tendinopathy of the long head of the biceps tendon (LHB) encompasses a range of pathology, including inflammatory tendinitis to degenerative tendinosis that can lead to pain, as well as instability of the LHB and its surrounding stabilizers. Accordingly, tenodesis of the LHB during shoulder surgery has been increasingly cited in the literature as a viable surgical option for the treatment of LHB pathology. While current treatment options include the use of multiple devices for tenodesis of the LHB, there remains a paucity of literature that investigates the biomechanical advantages of all-suture anchor devices compared to interference screws.

Tibial Slope Can Be Maintained During Medial Opening-Wedge Proximal Tibial Osteotomy With Sagittally Oriented Hinge, Posterior Plate Position, and Knee Hyperextension: A Cadaveric Study.

PURPOSE: The purpose of this study is (1) to determine if, when optimizing modern techniques, medial opening-wedge osteotomies can effectively maintain tibial slope and (2) to determine how different magnitude coronal plane corrections affect tibial slope. METHODS: Proximal tibial osteotomies (PTOs) were performed on 10 fresh-frozen cadaveric knees leaving a consistent lateral hinge, using either a 5-mm or a 10-mm trapezoidal wedged osteotomy plate. Techniques including posterior plate placement; a trapezoidal, sloped plate; and knee hyperextension were used during plate fixation to help close the anterior osteotomy gap. Medial coronal proximal tibia angle and posterior tibial slope were measured preosteotomy, after a 5-mm implant, and after a 10-mm implant using true anteroposterior and lateral fluoroscopic images. Three independent observers performed all radiographic measurements, and intraclass correlation coefficients were calculated. RESULTS: The 5-mm and 10-mm osteotomy plates increased the coronal medial proximal tibia angle by a mean of 3.4° (range, 3.0°-3.7°) and 7.3° (range, 6.7°-7.7°), respectively. The 5-mm and 10-mm trapezoidal wedged osteotomy plates decreased the posterior tibial slope by a mean of 0.9° (range, 0.5°-1.2°) and 0.3° (range, 0°-0.6°), respectively. Intraobserver reliability was found to be high for both the coronal medial proximal tibia angle (intraclass correlation coefficient [ICC] = 0.897 [0.821-0.946]) and the tibial slope measurements (ICC = 0.761 [0.672-0.826]). CONCLUSIONS: When optimizing the medial opening-wedge proximal tibial osteotomy, including utilization of a sagittally oriented hinge, placement of a trapezoidal plate posteriorly, and fixation with knee hyperextension, posterior tibial slope can be maintained regardless of the degree of coronal correction. CLINICAL RELEVANCE: Tibial slope has a significant effect on cruciate ligament stress and a better understanding of coronal plane correction, and its effect on tibial slope is critical when performing proximal tibia osteotomies.

Advanced 3-Dimensional Characterization of Hill-Sachs Lesions in 100 Anterior Shoulder Instability Patients.

PURPOSE: We sought to qualitatively and quantitatively describe characteristics of Hill-Sachs lesions (HSL) in a cohort of anterior shoulder instability patients using advanced 3-dimensional (3-D) modeling software and assess the impact of various HSL parameters on the HSL volume, location, and orientation in patients with anterior shoulder instability. METHODS: A total of 100 recurrent anterior instability patients with evidence of HSL with a mean age of 27.2 years (range = 18 to 43 years) were evaluated. Three-dimensional models of unilateral proximal humeri were reconstructed from CT scans, and the volume, surface area (SA), width, and depth of identified HSLs were quantified along with their location (medial, superior, and inferior extent). Multiple angular orientation measures of HSLs were recorded, including Hill-Sachs rim (HSLr) angle in order to classify the level and location of potential humeral head engagement. Mann-Whitney U test assessed the relationship between measured parameters. RESULTS: By volume, larger HSL had greater humeral head surface area (HH SA) loss (P = .001), HSL width (P = .001), were more medial (P = .015), and more inferior (P = .001). Additionally, more medial lesions had greater HSLr angles (P = 0.001). The mean depth, width, and volume of HSLs were 3.3 mm (range = 1.2-7.1 mm), 16.0 mm (range = 6.2-30.4 mm) and 449.2 mm3 (range = 62.0-1365.6 mm3), respectively. The medial border of the HSL extended to 17.2 ± 4.4 (range = 9.3-28.3 mm) off the most medial edge of the HH cartilage margin (medialization). The mean HSLr was 29.3 ± 10.5°. CONCLUSION: There was a statistically significant association between HSL medialization and HSL volume, position, and orientation. More medialized HSL have larger volume, greater width, more SA loss and higher lesion angles and are more inferior in the humeral head. As it has been established that more medialized lesions have poorer clinical outcomes, this study highlights that HS lesions have varying angles and medialization, which may portend eventual treatment and outcomes. LEVEL OF EVIDENCE: IV, case series.

Limited Predictive Value of the Instability Severity Index Score: Evaluation of 217 Consecutive Cases of Recurrent Anterior Shoulder Instability.

PURPOSE: To review the existing variables and their ability to predict recurrence of shoulder instability as it relates to the Instability Severity Index Score (ISIS), as well as evaluate any other pertinent imaging and patient history variables that may impact risk of recurrent anterior instability after arthroscopic Bankart repair. METHODS: All consecutive patients with recurrent anterior shoulder instability and who had arthroscopic instability repair were identified. Exclusion criteria were prior surgery on the shoulder, posterior or multidirectional instability, instability caused by seizure disorder, or a rotator cuff tear. All ISIS variables were recorded (age <20 years, sport type and level, hyperlaxity, Hill-Sachs on anteroposterior external rotation radiograph, loss of glenoid contour on anteroposterior radiograph), as well as additional variables: (1) number of instability events; (2) total time of instability; (3) glenoid bone loss (GBL) percent; and (4) Hill-Sachs measures (H/L/W/D/Volume). Postoperative outcomes were assessed based on the Western Ontario Shoulder Instability Index (WOSI), Single Assessment Numeric Evaluation (SANE) scores, and American Shoulder and Elbow Surgeons (ASES) scores, and recurrent anterior instability. Regression analysis was used to determine preoperative variables that predicted outcomes and failures. RESULTS: There were 217 consecutive patients (209 male patients [96.5%], 8 female patients [3.5%]) who met the inclusion criteria and were all treated with a primary arthroscopic shoulder stabilization during a 3.5-year period (2007-2011), with a mean follow-up time of 42 months (range, 26-58). The mean age at first instability event was 23.9 years (range, 16-48 years) and the mean cumulative ISIS score for the overall group was 3.6 (range, 1-6). Outcomes were improved from mean preoperative (WOSI = 1,050/2,100; ASES = 61.0; SANE = 52.5) to postoperative (WOSI = 305/2,100; ASES = 93.5; SANE = 95.5). A total of 11.5% (25/217) of patients had evidence of recurrent instability (subluxation or dislocation). Additionally, all 25 patients who failed postoperatively also had consistently inferior ASES, SANE, and WOSI outcome scores when compared with successfully treated patients. Factors associated with failure were GBL greater than 14.5% (P < .001), total time of instability symptoms greater than 3 months (P = .03), Hill-Sachs volume greater than 1.3 cm3 (P = .02), contact sports participation (P = .05), and age 20 years or younger (P < .01). There was no correlation in outcomes with Hill-Sachs on presence of glenoid contour loss on radiograph (P = .07), participation sports, or ISIS (mean = 3.4 success vs 3.9 failure, P > .05). CONCLUSIONS: At a mean follow-up of 42 months was an 11.5% failure rate after arthroscopic Bankart stabilization surgery. This study shows no correlation between treatment outcome and the ISIS measure, given a mean score of 3.4 for the overall cohort with little difference identified in those who failed. However, several important parameters previously unidentified were detected including, GBL greater than 14.5%, Hill-Sachs volume greater than 1.3 cm3, and duration of instability symptoms (>3 months). The ISIS may need to be redesigned to incorporate variables that more accurately portray the actual risk of failure after arthroscopic stabilization, including quantification of both glenoid and humeral head bone loss. LEVEL OF EVIDENCE: III (Retrospective Case Series).

Pullout Strength of All-Suture and Metallic Anchors in Repair of Lateral Collateral Ligament Injuries of the Elbow.

PURPOSE: To compare the biomechanical properties of metallic anchor (MA) and all-suture anchor (ASA) constructs in the anatomic reattachment of the lateral ulnar collateral ligament complex to its humeral insertion. METHODS: Twenty paired male human cadaveric elbows with a mean age of 46.3 years (range: 33-58 years) were used in this study. Each pair was randomly allocated across 2 groups of either MA or ASA. A single 3.5-mm MA or 2.6-mm ASA was then inserted flush into the lateral epicondyle. A dynamic tensile testing machine was used to perform cyclic loading followed by a load to failure test. During the cyclic loading phase, the anchors were sinusoidally tensioned from 10 N to 100 N for 1,000 cycles at a frequency of 0.5 Hz. In the load to failure test, the anchors were pulled at a rate of 3 mm/s. Load at 1-mm and 2-mm displacement, as well as load to ultimate failure were assessed. Clinical failure was defined as displacement of more than 2 mm. Normality of data was assessed with the Shapiro-Wilk test. Continuous data are presented as medians and compared with the Mann-Whitney U test and categorical data was compared with the χ2 test or Fisher exact test. RESULTS: Displacement was significantly greater for the ASA group during cyclic loading starting from the tenth cycle (P < .05). Displacement of more than 5 mm within the first 100 cycles was observed in 2 anchors in the ASA group. No difference was observed in loads required to displace 1 mm (MA: 146 N [6-169] vs ASA: 144 N [2-153]; P = .53) and 2 mm (MA: 171 N [13-202] vs ASA: 161 N [9-191]; P = .97), but there was a statistically significant difference between ultimate loads in favor of ASA in the load to failure test (MA: 297 N [84-343] vs 463 N [176-620]; P < .01). CONCLUSIONS: In the cyclic test, no difference in clinical failure defined as pull-out of more than 2 mm was observed between 3.5 mm MAs and 2.6 mm ASAs. In the ultimate load to failure analysis, no difference was observed between groups in force causing 1 and 2 mm of displacement, but there was a significant difference in favor of ASA in the pull to ultimate failure test. CLINICAL RELEVANCE: Potential benefits of all-suture anchors include preservation of bone stock, reduced radiographic artifacts, and easier revisions. Although their use has been investigated thoroughly in the shoulder, there remains a paucity of literature regarding displacement and pull-out strength in the elbow.

Utility of Allograft Talus as a Source for Grafting of Concurrent Humeral and Glenoid Defects Associated With Anterior Glenohumeral Instability: An Anthropometric Analysis.

PURPOSE: To compare morphologic data of the talus using magnetic resonance images with previously reported values of the humeral head and the glenoid as a potential graft source for both the humeral head as well as glenoid reconstruction in the setting of concomitant glenoid and humeral head defects. METHODS: All magnetic resonance images of the ankle were reviewed for assessment of the morphology and variation of the talus among individuals. Patients with post-traumatic, osteoarthritic, or surgical changes to the distal tibia about the mid- or hind- foot, or patients with incomplete medical records were excluded. Radiographic parameters that were measured included the maximum vertical height (MVH), the height to the talar neck, the radius of curvature (ROC) of the talar dome, ROC of the subtalar joint, and the maximum medial-to-lateral width of the talar dome. Demographic data also were collected on each individual. Statistical analysis was performed via a linear regression model with backwards elimination to determine which demographic data correlated most strongly with talar anthropometric values. RESULTS: A total of 82 study patients met inclusion criteria (59 male, 23 female; mean age 40.91 ± 14.69 years). Sex was found have a positive correlation of the following talar dimensions: MVH (P = .039), talar dome ROC (P < .001), and subtalar joint ROC (p = 0.001). Height was the most positive correlation for medial-to-lateral width (P < .001), height to the talar neck (P = .004), and also correlate for MVH (P = .004). Body mass index was found to have multicollinearity and was therefore not used as a variable. CONCLUSIONS: Allograft talus appears to be a viable graft, as demonstrated in this anthropometric study for both reconstruction of the glenoid and humeral head when cases of bipolar glenohumeral bone loss are present. CLINICAL RELEVANCE: This study aims to further evaluate potential allograft donor sites for bipolar lesions.

Postoperative Stiffness and Pain After Arthroscopic Labral Stabilization: Consider Anchor Arthropathy.

PURPOSE: To describe the key clinical, imaging, and arthroscopic characteristics of anchor arthropathy after arthroscopic shoulder stabilization procedures and, secondarily, to define risk factors for the development of anchor-induced arthropathy. METHODS: A total of 23 patients who underwent revision arthroscopic shoulder surgery and were diagnosed with glenohumeral arthropathy were retrospectively identified from prospectively collected data registries between January 2000 and May 2018. Data included initial diagnosis and index procedure performed, presenting arthropathy symptoms including duration, and examination findings before revision surgery. Pre-revision imaging was used to assess presence of glenohumeral osteoarthritis and chondromalacia, anchors/sutures, loose bodies, and labral pathology. The same parameters were recorded intraoperatively during revision surgery. Descriptive statistics were performed for demographic data and means with standard deviations were calculated for continuous data. A McNemar-Bowker test was used to analyze marginal homogeneity between preoperative imaging and intraoperative findings. RESULTS: Mean age at presentation was 33.4 ± 11.7 years (range 16-59, 17 male patients; 6 female patients). More than one half (13/23) developed symptoms within 10 months after index arthroscopic procedure (mean 32.2 ± 59.9 months, range <1 to 165.2 months) with 87% presenting with pain and 100% presenting with loss of motion on examination. Plain radiographs demonstrated humeral osteoarthritis in 57% (13/23) of patients, magnetic resonance imaging (MRI) revealed recurrent labral pathology in 19 of 23 (83%) patients, potential proud implants in 12 of 23 (52%), and loose bodies in 12 of 23 (52%). Intraoperatively, all had evidence of osteoarthritis; 22 of 23 (96%) had prominent implants. Humeral head chondromalacia was present in 21 of 23 patients (91%), the majority of which was linear stripe wear, and 6 of 23 (26%) had severe global glenohumeral osteoarthritis. Statistical analysis revealed a 54.5% (95% confidence interval 0.327-0.749) sensitivity of MRI identification of proud implants with a specificity of 100% (95% confidence interval 0.055-1). The ability of MRI to accurately assess chondromalacia of the humeral head (P = .342) or glenoid (P = .685) was not statistically significant. CONCLUSIONS: Anchor arthropathy is characterized by symptoms of pain and stiffness on examination and in many cases develops early after stabilization surgery (<10 months). Implants were implicated in the majority of cases of humeral head chondromalacia. MRI scans may produce false-negative identification of proud implants and can be a poor predictor of the severity of chondromalacia and intra-articular pathology; thus, a high index of clinical suspicion is necessary in patients with motion loss and pain postoperatively. LEVEL OF EVIDENCE: Level IV, case series.