Management of Glenoid Bone Loss in Shoulder Instability: Where We Are in 2023.

The management of glenoid bone loss in shoulder instability can be challenging. Although shoulder instability can often be managed with arthroscopic soft-tissue procedures alone, the extent of glenoid bone loss and bipolar bone defects may require bone augmentation procedures for restoration of stability. In this setting, patient evaluation, examination, treatment options, and surgical pearls are vital. Furthermore, a treatment algorithm is established to guide both indications and the technical application of procedures including Bankart repair with remplissage, Latarjet procedure, and glenoid bone graft options. The limitations, complications, and current research pertinent to each treatment assist in guiding treatment.

Leadership in Orthopaedic Surgery: Creating a Highly Effective Leader.

Strong leadership is associated with improved outcomes in multiple domains, including orthopaedic surgery. There are multiple leadership styles, including transformational, transactional, and laissez-faire leadership. An effective leader understands the importance of verbal and nonverbal communication, emotional intelligence, preparation, and mindset on team performance. Orthopaedic surgeons serve as leaders in the operating room, in the outpatient setting, and on committees. Leadership skills can be developed through leadership-specific evaluations and training.

Editorial Commentary: For Shoulder Hill-Sachs Lesion Remplissage, Medial Anchor Position Must Be Optimized to Achieve Stability Yet Minimize External Rotation Loss.

An off-track Hill-Sachs lesion (HSL) is a significant risk factor for recurrent shoulder instability after arthroscopic Bankart repair. Bankart repair combined with remplissage can better restore shoulder stability versus isolated Bankart repair when treating a combined Bankart lesion and off-track HSL. However, remplissage may be nonanatomic and associated with limitation of shoulder external rotation (ER), especially when the arm is in a 90° shoulder abduction position. Excessive medial placement of remplissage anchors is associated with postoperative ER loss and increased glenohumeral cartilage degeneration. The use of 2 medial anchors results in lower articular forces. Thus, in patients with shoulder instability, we recommend using 2 remplissage anchors in those with a Bankart lesion plus an off-track HSL. The anchors should be placed medially to achieve stability-but not so medial as to result in postoperative stiffness and significant ER loss.

What is the deviation in 3D preoperative planning software? A systematic review of concordance between plan and actual implant in reverse total shoulder arthroplasty.

BACKGROUND: Three-dimensional (3D) preoperative planning software for reverse total shoulder arthroplasty (rTSA) has been implemented in recent years in order to increase accuracy, improve efficiency, and add value to the outcome. A comprehensive literature review is required to determine the utility of preoperative 3D planning software in guiding orthopedic surgeons for implant placement in rTSA. We hypothesize that implementation of 3D preoperative planning software in the setting of rTSA leads to high concordance with minimal deviation from the preoperative plan. METHODS: A comprehensive and iterative literature review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) using the PubMed, Embase, OVID Medline, Scopus, Cinahl, Web of Science, and Cochrane databases for original English-language studies evaluating the impact of preoperative planning software usage on rTSA outcomes published from January 1, 2000, to present. Blinded reviewers conducted multiple screens. All included studies were graded based on level of evidence, and data concerning patient demographics and postoperative outcomes were extracted. RESULTS: Nine articles met inclusion criteria (1 level II, 3 level III, and 5 level IV articles), including 415 patients and 422 shoulders. Of the patients who underwent rTSA, 235 were female and 140 were male, although 3 studies (n = 40) did not report sex breakdowns for rTSA patients. The average age was 72.7 years. Four studies (79 shoulders) reported implant final position as mean deviation from planned version and planned inclination. Six studies (n = 236) reported screw angle deviation, fixation, length, and concordance. Concordance with the preoperative plan was measured in 3 studies (n = 178), resulting in complete concordance of 90% (n = 100), arthroplasty type concordance (rTSA vs. TSA) of 100% (n = 100), and glenosphere size concordance between 93% (n = 100) and 88% (n = 76). For screw length concordance, baseplate screw matched by 81% (n = 76) and 100% (n = 2), and upper (n = 35) and lower (n = 35) screw length concordance was observed as 74% and 69%, respectively. The use of preoperative planning (n = 178) was associated with low deviation from preoperative plan, more 2-screw fixations, and longer average screw length in comparison with an unplanned cohort. CONCLUSION: The use of preoperative planning software in the setting of rTSA results in minimal deviation from preoperative plan. High levels of concordance in screw angle, screw length, and glenosphere size were observed. Further prospective studies should be conducted to further substantiate these results.

Accuracy and Reliability of Imaging Modalities for the Diagnosis and Quantification of Hill-Sachs Lesions: A Systematic Review.

PURPOSE: To determine the reliability and accuracy of different imaging modalities in assessing Hill-Sachs lesions within the setting of anterior shoulder instability. METHODS: A systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines using the PubMed, Scopus, Embase, and Cochrane Library databases. The inclusion criteria were clinical trials or cadaveric studies that assessed the accuracy of humeral head bone loss imaging or reliability and English-language articles. The exclusion criteria were animal studies; imaging studies without measures of accuracy, reliability, or clinical predictive power; studies of shoulder injuries without humeral head bone loss; editorials; abstracts; reviews; case reports; and surveys. The search terms included "imaging" OR "radiographic" OR "CT" OR "MRI" AND "Hill-Sachs" OR "humeral head bone loss." Assessment of the methodologic quality of the included studies was performed using the original Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool. RESULTS: Forty studies (2,560 shoulders) met the inclusion criteria and were assessed. For diagnosing the presence of Hill-Sachs lesions, computed tomography (CT) arthrography had the highest reported accuracy (median, 91%; range, 66%-100%). For the same assessment, CT arthrography also had the greatest reported sensitivity (median, 94%; range, 50%-100%). For the quantification of Hill-Sachs lesion parameters, reported intraobserver reliabilities were highest for 3-dimensional (3D) CT (intraclass correlation coefficient [ICC] range, 0.916-0.999), followed by 2-dimensional CT (ICC range, 0.858-0.861) and magnetic resonance imaging (MRI) (ICC range, 0.28-0.97). For the same quantification parameters, interobserver reliabilities were also reported for 3D CT (ICC range, 0.772-0.996), 2-dimensional CT (ICC range, 0.721-0.879), and MRI (κ range, 0.444-0.700). Intraobserver reliabilities for determining glenoid tracking were only reported for 3D CT (κ range, 0.730-1.00; ICC range, 0.803-0.901) and MRI (ICC range, 0.770-0.790). CONCLUSIONS: This study shows that the current literature supports a variety of different imaging modalities that provide clinically acceptable accuracy in diagnosing and quantifying Hill-Sachs lesions, as well as determining whether they will cause persistent anterior shoulder instability. Furthermore, this systematic review justifies that further research is needed to help develop a treatment algorithm on the proper imaging modalities needed to help treat patients with anterior shoulder instability that is both reliable and financially acceptable. LEVEL OF EVIDENCE: Level IV, systematic review of Level I through IV studies.

Evaluation and Management of Glenohumeral Instability With Associated Bone Loss: An Expert Consensus Statement Using the Modified Delphi Technique.

PURPOSE: To establish an international expert consensus, using the modified Delphi technique, on the evaluation and management of glenohumeral instability with associated bone loss. METHODS: A working group of 6 individuals generated a list of statements related to history and physical examination, imaging and specialized diagnostic tests, bone loss quantification and classification, treatment outcomes and complications, and rehabilitation for the management of glenohumeral instability associated with bone loss to form the basis of an initial survey for rating by a group of experts. The expert group (composed of 22 high-volume glenohumeral instability experts) was surveyed on 3 occasions to establish a consensus on the statements. Items with over 70% agreement and less than 10% disagreement achieved consensus. RESULTS: After a total of 3 rounds, 31 statements achieved consensus. Eighty-six percent of the experts agreed that a history of multiple dislocations and failed soft-tissue surgery should raise suspicion about the possibility of an associated bone deficit. Ninety-five percent of the experts agreed that 3-dimensional (3D) computed tomography (CT) is the most accurate diagnostic method to evaluate and quantify bone loss. Eighty-six percent of the experts agreed that any of the available methods to measure glenoid bone deficiency is adequate; however, 91% of the experts thought that an en face view of the glenoid using 3D CT provides the most accurate method. Ninety-five percent of the experts agreed that Hill-Sachs lesions are poorly quantified and classified by current imaging systems. Ninety percent of the experts agreed that in cases with a glenoid bone deficit greater than 20%, glenoid bone graft reconstruction should be performed and any of the available options is valid. There was no consensus among experts on how Hill-Sachs injuries should be managed or on how postoperative rehabilitation should be carried out. CONCLUSIONS: The essential statements on which the experts reached consensus included the following: A history of multiple dislocations and failed soft-tissue surgery should make surgeons consider the possibility of an associated bone deficit. Three-dimensional CT is the most accurate diagnostic method to evaluate and quantify bone loss. Although any of the available methods to measure glenoid bone deficiency is adequate, an en face view of the glenoid using 3D CT provides the most accurate method. Hill-Sachs lesions are poorly quantified and classified by current imaging systems. Finally, in cases with a glenoid bone deficit greater than 20%, glenoid bone graft reconstruction should be performed. LEVEL OF EVIDENCE: Level V, consensus statement.

Management of Shoulder Instability in 2020: What, When, and How.

Anterior glenohumeral instability remains a common clinical problem in the athletic and working patient populations, and further, recurrence rates following stabilization surgery continue to be problematic. Over the past 5 years, there have been substantial improvements in the understanding of anterior shoulder instability. To better counsel and treat patients, it is imperative for surgeons to have a comprehensive understanding of the epidemiology of shoulder instability, the anatomy of the glenohumeral joint particularly as it relates to glenoid and humeral head bone loss, surgical indications, and surgical techniques. These critical topics are summarized in an effort to provide a complete guide to managing anterior shoulder instability in 2020.

Editorial Commentary: Evidence to Support Surgical Intervention for First-Time Shoulder Instability: Stabilize Them Early!

Historically, a primary anterior instability event has been treated nonoperatively. In the literature, a multitude of outcome scores and definitions for recurrence of instability complicates the interpretation and synthesis of evidence-based recommendations. However, there is an emerging body of high-quality evidence that early surgical stabilization yields better overall outcomes. A wait-and-see approach would be acceptable if it was without detrimental effects, but there is a cost to recurrence of instability events, such as more extensive soft-tissue, cartilage, and bony lesions. Young age, male sex, and contact sport participation have been identified as risk factors for recurrence of anterior shoulder instability, and today, these patients are routinely recommended surgical treatment. It is also paramount to identify concomitant injury following the primary anterior instability event. The sensitivity, specificity, and reliability of radiographs is suboptimal, and the threshold to obtain advanced imaging such as computed tomography or magnetic resonance imaging with 3-dimensional reconstructions should be low. Taking into account the low non-recurrence complication rate following arthroscopic stabilization, early surgical intervention should be considered following the first instability event.

Conversion of Failed Proximal Long Head of the Biceps Tenodesis to Distal Subpectoral Tenodesis: Outcomes in an Active Population.

PURPOSE: To assess failure rates and patient reported outcomes following revision of failed proximal long head of the biceps (LHB) tenodesis. METHODS: Patients from an active-military population who underwent revision proximal (suprapectoral) to distal (subpectoral) LHB tenodesis were prospectively enrolled. Patients were included if they were between the ages of 16 and 60 years presenting after a previous biceps tenodesis with mechanical failure and clinical failure, defined as Single Assessment Numeric Evaluation (SANE) or American Shoulder and Elbow Surgeons (ASES) <70. Exclusion criteria were concomitant rotator cuff repair or debridement, full-thickness rotator cuff tear, extensive labral tears, or any evidence of glenohumeral arthritis. Pre- and postoperative SANE and ASES were documented and analyzed. RESULTS: From 2004 to 2010, a total of 12 patients (all male) with a mean age of 39.9 years (range, 30-54 years) were assessed at a mean follow-up time of 29 months (range, 24-38 months). Nine patients presented with a failed tenodesis construct located at the top of the bicipital groove and 9 patients had LHB tendons originally affixed with an interference screw. Diagnostic arthroscopy revealed that the majority of patients (10/12) had excessive scarring at the site of previous fixation. Mean preoperative assessments of SANE (70.4) and ASES (59.9) improved postoperatively to SANE (90.3; P < .01) and ASES (89.8; P < .01). No patients were lost due to follow-up, and there were no reported complications or failures. All patients returned to full active duty and were able to perform all required physical tests before returning to their vocation. CONCLUSIONS: Patients presenting with symptoms following a proximal LHB tenodesis can be successfully converted to a distal (subpectoral) LHB tenodesis with favorable outcomes. Although in a small sample, there was excessive scarring and synovitis in a majority, which improved significantly when treated with a revision subpectoral tenodesis with minimal complication risk and no reported failures. LEVEL OF EVIDENCE: IV (Therapeutic case series).

Latarjet Procedure to Restore Glenohumeral Stability in a Patient With a Postage Stamp Fracture.

The "postage stamp fracture" is an anterior glenoid rim fracture following arthroscopic repair of a Bankart lesion. Often occurring at the time of an acute trauma, a fracture line propagates though the previous Bankart repair anchor sites, resulting in recurrent anterior instability of the glenohumeral joint. The resultant glenoid rim fracture edge gives a similar appearance as the edge of a stamp, with the osseous edge having the classic "perforation" pattern. When patients present with a postage stamp fracture, even in the setting of subcritical glenoid bone loss, we believe that additional soft-tissue stabilization procedures and/or fracture fixation pose a significant risk of failure. In our opinion, a Latarjet procedure is recommended in a majority of patients with a postage stamp fracture for restoration of glenohumeral stability. The procedure offers a reliable, reproducible surgical intervention that controls for many of the factors that can make arthroscopic revision unreliable, such as poor bone quality, adhesions, labral degeneration, and bone loss. Here, we outline our preferred surgical technique to restore glenohumeral stability using the Latarjet procedure for a patient with a postage stamp fracture.

Biomechanical Analysis Evaluating Meniscal Extrusion After Knotless Suture Anchor Fixation for Segmental Medial Meniscal Allograft Transplantation.

Background: Segmental medial meniscal allograft transplantation (MAT) has been shown to restore knee biomechanics; however, stable fixation of the transplantation is critical to avoid extrusion and maximize healing. Purpose: To evaluate the degree of meniscal extrusion and biomechanical function of segmental medial MAT performed with meniscocapsular sutures versus repair augmentation with knotless suture anchors. Study Design: Controlled laboratory study. Methods: Segmental midbody medial meniscectomy and subsequent segmental medial MAT were performed on 10 fresh-frozen cadaveric knees. The knees were then loaded in a dynamic tensile testing machine to 1000 N for 60 seconds at 0°, 30°, 60°, and 90° of flexion, and 4 conditions were tested: (1) intact, (2) segmental defect, (3) inside-out segmental repair, and (4) anchor plus inside-out segmental repair of the medial MAT. Meniscal extrusion was measured using high-fidelity ultrasound imaging. The mean contact area and the mean and peak contact pressures were assessed with submeniscal pressure-mapping sensors. Data from testing conditions were compared with 2-way repeated-measures analysis of variance, with pairwise comparison using the Bonferroni method. Results: At 90° of flexion, the segmental defect state showed a higher degree of meniscal extrusion compared with all other states (P ≤ .012). There was no difference in the degree of meniscal extrusion between the intact state and the inside-out repair or anchor plus inside-out segmental repair states at all knee flexion angles (P > .05). There was no significant difference in the mean and peak contact pressures among the 4 states at all flexion angles except that at 0° of knee flexion there was significantly lower peak contact pressure at the medial compartment after anchor plus inside-out segmental repair compared with the segmental defect state (P = .048). Conclusion: Meniscal extrusion was not significantly increased at any flexion angle after segmental resection. The addition of knotless anchors did not improve meniscal extrusion or contact pressures/area compared with capsular repair alone. The addition of knotless anchors did improve contact mechanics from the segmental defect state, but only at 0° of flexion. Clinical Relevance: The addition of knotless suture anchors to segmental meniscal transplantation increased stabilization of the meniscus at full extension compared with repair with sutures alone. This increased stabilization may lead to better long-term outcomes.

Increased Posterior Tibial Slope Increases Force on the Posterior Medial Meniscus Root.

BACKGROUND: Posterior medial meniscus root (PMMR) tears have been associated with increased posterior tibial slope, but this has not been fully evaluated biomechanically. In addition, the effects of knee flexion and rotation on the PMMR are not well understood biomechanically because of technological testing limitations. A novel multiaxial force sensor has made it possible to elucidate answers to these questions. PURPOSE: (1) To determine if increased posterior tibial slope results in increased posterior shear force and compression on the PMMR, (2) to evaluate how knee flexion angle affects PMMR forces, and (3) to assess how internal and external rotation affects force at the PMMR. STUDY DESIGN: Controlled laboratory study. METHODS: Ten fresh-frozen cadaveric knees were tested in all combinations of 3 posterior tibial slopes and 4 flexion angles. A multiaxial force sensor was connected to the PMMR and installed below the posterior tibial plateau maintaining anatomic position. The specimen underwent a 500-N compression load followed by a 5-N·m internal torque and a 5-N·m external torque. The magnitude and direction of the forces acting on the PMMR were measured. RESULTS: Under joint compression, an increased tibial slope significantly reduced the tension on the PMMR between 5° and 10° (from 13.5 N to 6.4 N), after which it transitioned to a significant increase in PMMR compression, reaching 7.6 N at 15°. Under internal torque, increased tibial slope resulted in 4.7 N of posterior shear at 5° significantly changed to 2.0 N of anterior shear at 10° and then 8.2 N of anterior shear at 15°. Under external torque, increased tibial slope significantly decreased PMMR compression (5°: 8.9 N; 10°: 4.3 N; 15°: 1.1 N). Under joint compression, increased flexion angle significantly increased medial shear forces of the PMMR (0°, 3.8 N; 30°, 6.2 N; 60°, 7.3 N; 90°, 8.4 N). Under internal torque, 90° of flexion significantly increased PMMR tension from 2.3 N to 7.5 N. Under external torque, 30° of flexion significantly increased PMMR compression from 4.7 N to 12.2 N. CONCLUSION: An increased posterior tibial slope affects compression and anterior shear forces at the PMMR. An increased flexion angle affects compression, tension, and medial shear forces at the PMMR. CLINICAL RELEVANCE: The increase in compression and posterior shear force when the knee is loaded in compression may place the PMMR under increased stress and risk potential failure after repair. This study provides clinicians with information to create safer protocols and improve repair techniques to minimize the forces experienced at the PMMR.

Humeral Head Reconstruction With Osteochondral Allograft: Bone Plug Optimization for Hill-Sachs Lesions Using CT-Based Computer Modeling Analysis.

Background: Engaging Hill-Sachs lesions (HSLs) pose a significant risk for failure of surgical repair of recurrent anterior shoulder instability. Reconstruction with fresh osteochondral allograft (OCA) has been proposed as a treatment for large HSLs. Purpose: To determine the optimal characteristics of talus OCA bone plugs in a computer-simulated HSL model. Study Design: Descriptive laboratory study; Level of evidence, 6. Methods: Included were 132 patients with recurrent anterior instability with visible HSLs; patients who had multidirectional instability or previous shoulder surgery were excluded. Three-dimensional computed tomography models were constructed, and a custom computer optimization algorithm was generated to maximize bone plug surface area at the most superior apex (superiorization) and minimize its position relative to the most medial margin of the HSL defect (medialization). The optimal number, diameter, medialization, and superiorization of the bone plug(s) were reported. Percentages of restored glenoid track width and conversion from off- to on-track HSLs after bone plug optimization were calculated. Results: A total of 86 patients were included in the final analysis. Off-track lesions made up 19.7% of HSLs and, of these, the mean bone plug size was 9.9 ± 1.4 mm, with 2.2 mm ± 1.7 mm of medialization and 3.3 mm ± 2.9 mm of superiorization. The optimization identified 21% of HSLs requiring 1 bone plug, 65% requiring 2 plugs, and 14% requiring 3 plugs, with a mean overall coverage of 60%. The mean width of the restored HSLs was 68%, and all off-track HSLs (n = 17) were restored to on-track. A Jenks natural-breaks analysis calculated 3 ideal bone plug diameters of 8 mm (small), 10.4 mm (medium), and 12 mm (large) in order to convert this group of HSLs to on-track. Conclusion: Using a custom computer algorithm, we have demonstrated the optimal talus OCA bone plug diameters for reconstructing HSLs to successfully restore the HSL track and, on average, 60% of the HSL surface area and 68% of the HSL width. Clinical Relevance: Reconstructing HSLs with talus OCA is a promising treatment option with excellent fit and restoration of HSLs. This study will help guide surgeons to optimize OCA bone plugs from the humeral head, femoral head, and talus for varying sizes of HSLs.

Fresh Distal Tibial Allograft: An Updated Graft Preparation Technique for Anterior Shoulder Instability.

Fresh distal tibia allograft (DTA) has been gaining popularity among surgeons as an anatomic reconstruction option for the treatment of significant glenoid bone loss. Fresh DTA results in a clinically stable joint with excellent clinical outcomes and minimal graft resorption, and it has similar outcomes as the Latarjet procedure. Proper graft preparation and fixation are critical to ensuring optimal outcomes. The purpose of this Technical Note is, therefore, to describe our updated technique for DTA preparation that highlights precise cutting anatomy, sizing options, and use of orthobiologics to optimize distal tibia graft union to the native glenoid surface.

Primary Distal Tibia Allograft for Restoration of Glenohumeral Stability with Anterior Glenoid Bone Loss.

Recurrent shoulder instability with glenoid bone deficiency remains an increasing risk for failed shoulder stabilization surgery. Numerous free bone block procedures for primary treatment of anterior shoulder stability have been introduced as an alternative for the Latarjet procedure, including both autografts and allografts. Among such options is the fresh distal tibial allograft (DTA), a dense weightbearing bone without donor site morbidity and excellent conformity to the native glenoid. The aim of this Technical Note is therefore to describe our surgical technique for use of fresh DTA as a free bone block choice in the setting of primary anterior glenoid reconstruction in a patient with recurrent shoulder instability.

Shoulder strength outcomes after reverse total shoulder arthroplasty: a systematic review and descriptive synthesis.

Hypothesis and Background: There is no differences in abduction, internal rotation, or external rotation strength after reverse total shoulder arthroplasty (rTSA) with or without subscapularis repair. Repair of the subscapularis can be effective in the setting of rTSA. However, consensus has yet to be reached on whether postoperative strength after rTSA differs based on subscapularis management. The purpose of this review is to evaluate shoulder strength outcomes after rTSA with and without subscapularis tendon repair. Methods: A comprehensive literature review was conducted using the key terms "subscapularis" AND "reverse total shoulder arthroplasty" AND "muscle strength" in PubMed, Embase, Web of Science, Cochrane Reviews and Trials, and Scopus. Original, English-language studies evaluating shoulder strength outcomes after rTSA published from January 1, 2000, to present were evaluated. Strength outcomes reported included abduction strength (kg) and internal rotation strength (kg) using an electric spring balance and external rotation strength (lb) using a handheld dynamometer. Heterogeneity of data in the included studies did not allow for meta-analysis. Resuts: The search yielded 4253 unique results, which were screened for inclusion according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Two articles met eligibility criteria and were included in the final full-text review. A total of 267 shoulders were represented, 111 with subscapularis repair and 156 without subscapularis repair. No significant differences in abduction (P = .39), internal rotation (P = .09), and external rotation (P = .463) strength were observed between subscapularis repair and nonrepair groups. Conclusion: There were no differences in abduction, internal rotation, or external rotation strength after rTSA with or without subscapularis repair. The literature on postoperative strength outcomes after rTSA is limited, and further study in this area is warranted.

Arthroscopic Characterization, Treatment, and Outcomes of Glenoid Labral Articular Disruption Lesions.

BACKGROUND: The pathoanatomy of glenoid labral articular disruption (GLAD) lesions has been inconsistently and poorly defined in the literature. PURPOSE/HYPOTHESIS: The purpose was to characterize GLAD lesions as they pertain to the pathoanatomy of labrum, cartilage, and bony structures, and to correlate findings with patient-reported outcomes (PROs). We hypothesized that greater degrees of bony and cartilaginous involvement would correlate with worse outcomes. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: All patients with a diagnosis of a GLAD lesion or a reverse GLAD (RGLAD) lesion at the time of diagnostic arthroscopy (January 2006-February 2019) were included in this study. Patients with ≥13.5% bone loss or previous ipsilateral shoulder surgery were excluded. Patient charts and operative reports/photos were used to identify the location of injury, extent of injury (labral, chondral, and bony), associated injuries, demographic factors, and treatment performed. Three injury patterns were identified: small (type 1), with no chondral defect after labral repair; large (type 2), with residual chondral defect after labral repair; and bony (type 3), with associated glenoid bone loss amenable to labral repair. Characterizations were cross-referenced to PROs at a mean follow-up of 5.5 years (range, 2.6-10.5 years): American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation, shortened version of Disabilities of the Arm, Shoulder and Hand, and patient satisfaction. RESULTS: In total, 50 patients were included, with 40 having GLAD and 10 having RGLAD lesions (mean age, 34.7 and 33.2 years, respectively). There were 14 (35%) type 1, 22 (55%) type 2, and 4 (10%) type 3 GLAD injuries. All PROs improved without any differences in the 3 subgroups postoperatively (ASES, 95.1 vs 91.3 vs 98.8, type 1, 2, and 3, respectively). RGLAD injuries were majority type 2 (7/10; 70%) with the remainder being type 1 (3/10; 30%). CONCLUSION: With GLAD and RGLAD injuries, 3 distinct injury patterns can be observed correlating with the presence/absence of chondral loss after labral repair or the presence of associated bone loss. This descriptive characterization can facilitate arthroscopic treatment decisions. Future large studies are needed to determine if this is prognostic in nature.

Impact of prior anterior instability on shoulder arthroplasty outcomes: a systematic review.

Background: Anterior shoulder instability (ASI) is a frequently encountered pathology. Patients with a history of ASI have an increased rate of developing glenohumeral osteoarthritis and becoming candidates for shoulder arthroplasty. This systematic review aims to synthesize outcomes for patients undergoing shoulder arthroplasty with a history of ASI. Methods: A comprehensive literature review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) using PubMed, Embase, OVID Medline, Scopus, CINAHL, Web of Science, and Cochrane databases for studies evaluating the impact of prior ASI on total shoulder arthroplasty (TSA), reverse TSA, and/or hemiarthroplasty outcomes, with a minimum follow-up of 12 months. Studies were graded by level of evidence and data concerning patient demographics and outcomes were extracted. Results: Sixteen articles met the inclusion criteria, including 596 patients (413 male, 181 female). The average age of the control and prior ASI groups were 57.5 and 57.0 years, respectively. Overall, 251 patients were treated operatively, 132 nonoperatively, and 213 were controls without a history of prior ASI. Shoulder arthroplasty techniques included TSA (436 shoulders), reverse TSA (130 shoulders), and hemiarthroplasty (14 shoulders). Prior anterior stabilization management included soft tissue repair, bony augmentation, and nonoperative treatment. Almost all studies reported no significant difference in subjective and functional arthroplasty outcomes between control and prior ASI groups, or between patients with prior ASI treated nonoperatively vs. surgically. Conclusion: Shoulder arthroplasty in the setting of prior ASI results in improved subjective and functional outcome scores that are comparable to patients without a history of instability.

Biomechanical Analysis of Segmental Medial Meniscal Transplantation in a Human Cadaveric Model.

BACKGROUND: Meniscal deficiency has been reported to increase contact pressures in the affected tibiofemoral joint, possibly leading to degenerative changes. Current surgical options include meniscal allograft transplantation and insertion of segmental meniscal scaffolds. Little is known about segmental meniscal allograft transplantation. PURPOSE: To evaluate the effectiveness of segmental medial meniscal allograft transplantation in the setting of partial medial meniscectomy in restoring native knee loading characteristics. STUDY DESIGN: Controlled laboratory study. METHODS: Ten fresh-frozen human cadaveric knees underwent central midbody medial meniscectomy and subsequent segmental medial meniscal allograft transplantation. Knees were loaded in a dynamic tensile testing machine to 1000 N for 20 seconds at 0°, 30°, 60°, and 90° of flexion. Four conditions were tested: (1) intact medial meniscus, (2) deficient medial meniscus, (3) segmental medial meniscal transplant fixed with 7 meniscocapsular sutures, and (4) segmental medial meniscal transplant fixed with 7 meniscocapsular sutures and 1 suture fixed through 2 bone tunnels. Submeniscal medial and lateral pressure-mapping sensors assessed mean contact pressure, peak contact pressure, mean contact area, and pressure mapping. Two-factor random-intercepts linear mixed effects models compared pressure and contact area measurements among experimental conditions. RESULTS: The meniscal-deficient state demonstrated a significantly higher mean contact pressure than all other testing conditions (mean difference, ≥0.35 MPa; P < .001 for all comparisons) and a significantly smaller total contact area as compared with all other testing conditions (mean difference, ≤140 mm2; P < .001 for all comparisons). There were no significant differences in mean contact pressure or total contact area among the intact, transplant, or transplant-with-tunnel groups or in any outcome measure across all comparisons in the lateral compartment. No significant differences existed in center of pressure and relative pressure distribution across testing conditions. CONCLUSION: Segmental medial meniscal allograft transplantation restored the medial compartment mean contact pressure and mean contact area to values measured in the intact medial compartment. CLINICAL RELEVANCE: Segmental medial meniscal transplantation may provide an alternative to full meniscal transplantation by addressing only the deficient portion of the meniscus with transplanted tissue. Additional work is required to validate long-term fixation strength and biologic integration.