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.

Preoperative patient factors that predict achieving the minimal clinically important difference following arthroscopic treatment of snapping scapula syndrome.

BACKGROUND: The aim of this study was to define the minimal clinically important difference (MCID) values for patient-reported outcomes (PROs) after arthroscopic treatment of snapping scapula syndrome (SSS) using a distribution-based method, and to identify demographic, clinical, and intraoperative factors significantly associated with the achievement of MCID. It was hypothesized that subjective satisfaction scores after the procedure would be strongly associated with the achievement of MCID thresholds for the PROs and that pain, preoperative response to injection, and a scapulectomy in addition to bursal resection would be predictive of clinically relevant improvement. METHODS: Patients who underwent arthroscopic treatment of SSS between October 2005 and September 2020 with a minimum of 2-year short-term postoperative follow-up were enrolled in this retrospective single-center study. The MCID was calculated using a distribution-based approach for the following PROs: 12-Item Short Form Health Survey (SF-12), American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Quick Disabilities of the Arm, Shoulder, and Hand questionnaire (QuickDASH), Single Assessment Numeric Evaluation (SANE), and visual analog scale (VAS) pain "today" and "at worst." The association between achievement of the MCID and postoperative subjective satisfaction was investigated, and factors associated with achievement of MCID were determined using bivariate analysis. RESULTS: Of a total of 190 patients assessed for eligibility, 77 patients (38.1 ± 14.3 years; 36 females) were included. Within the study population, statistically significant improvements in postoperative SF-12 physical component summary (PCS) (P < .001) and mental component summary (MCS) (P < 0.034), ASES (P < .001), QuickDASH (P < .001), SANE (P < .001), and VAS pain (P < .001) scores were observed at the minimum 2-year follow-up. The calculated MCID threshold values based on the study population were 5.0 for SF-12 PCS, 5.8 for SF-12 MCS, 11.3 for ASES, -10.5 for QuickDASH, 14.7 for SANE, 1.5 for VAS pain, and 1.7 for VAS pain at worst. Reaching the MCID was strongly associated with postoperative satisfaction (rated on a scale of 1-10). Across the PROs, younger age, favorable preoperative response to injection, partial scapuloplasty or scapulectomy, no prior surgery, and pain and function at baseline were significantly associated with attaining MCID. CONCLUSIONS: Patients who underwent arthroscopic treatment for SSS experienced clinically significant improvements in functional scores, pain, and quality of life. This study demonstrated predictive roles for certain patient-specific factors and diagnostic variables for achieving MCID in PROs, which may help surgeons preoperatively assess the probability of success and manage patient expectations.

Biomechanical comparison of 3 latissimus dorsi transfer sites for reverse total shoulder arthroplasty in the absence of teres minor.

BACKGROUND: Reverse total shoulder arthroplasty is often performed to treat rotator cuff tear arthropathy with irreparable rotator cuff tears. Patients with full-thickness tears involving the posterior cuff and teres minor specifically lose active external rotation of the humerus, limiting activities of daily living. A latissimus dorsi transfer has been described as one potential solution, but few studies have compared different latissimus dorsi transfer sites. This study assesses the biomechanics of 3 latissimus dorsi transfer sites, examining external rotation, deltoid muscle forces, and force across the glenoid for specific activities. METHODS: The Newcastle Shoulder Model was modified to include a Delta III reverse shoulder arthroplasty and was used to model the effects of 3 latissimus dorsi transfer sites-anterior, posterolateral, and posterodistal-in the setting of teres minor deficiency. The latissimus dorsi was represented by 5 muscle elements approximating anatomic fascicle divisions. Kinematic data sets representing common activities were input into the model, allowing calculation of muscle forces and glenoid loads. RESULTS: Each of the 3 latissimus dorsi transfer sites demonstrated a change of moment arm from internal to external rotation with increased magnitude. Average maximum deltoid muscle forces and glenoid loading across all motions decreased for each of the 3 transfer sites, with the greatest decreased force noted for the posterior deltoid. This decrease in deltoid force and glenoid loading was significantly greater with the anterior and posterolateral transfer sites, relative to the posterodistal site. DISCUSSION: Latissimus dorsi transfer to all 3 sites in the setting of reverse total shoulder arthroplasty and posterior rotator cuff deficiency resulted in large external rotation moment arms. The transferred latissimus dorsi shared the external rotation load and resulted in decreased deltoid forces and glenoid loading with very small differences between the 3 transfer sites. The posterodistal location reduced deltoid force and glenoid loading to a lower degree compared with other sites, but it also showed that it did not alter the tendon length compared with the native shoulder.

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

PURPOSE: To use computed tomography (CT) to determine a reproducible method of coracoid measurement to compare the ability of the classic Latarjet technique and the congruent arc modification (CAM) to restore native glenoid diameter and to develop a preoperative planning algorithm for glenoid restoration with a goal of achieving an on-track shoulder. METHODS: Coracoid dimensions were measured on multiplanar reconstructed shoulder CT scans of patients aged 18 to 45 years obtained between December 1, 2019, and March 13, 2020. Patients were excluded if CT demonstrated osteophyte formation, glenoid dysplasia, coracoid fracture, or tumor. The proportion of glenoid diameter able to be restored using classic Latarjet technique and CAM were calculated. A treatment algorithm was proposed considering the amount of bone loss present and coracoid dimensions. RESULTS: Coracoid dimensions of 117 consecutive patients were measured and varied considerably (length: 17.5-31.8 mm, width: 9.1-20.5 mm, thickness: 6.1-15.7 mm). While most patients had harvestable coracoid length ≥20 mm (male: 96.3% vs female: 94.4%, P = .65), only 27.8% of female patients had coracoid thickness ≥10 mm. When comparing Latarjet techniques, there was no difference in the proportion of patients in whom 30% glenoid diameter could be fully restored, but CAM was able to restore at least 35% in more male and female patients (98.8% vs 79.0% and 100% vs 61.1%, respectively, P = .00001). Intra- and inter-rater reliability was excellent ( intraclass correlation coefficient ≥0.950 for all dimensions). CONCLUSIONS: We describe a reliable method of measuring coracoid dimensions for preoperative planning of glenoid restoration. The classic Latarjet technique reliably restores the glenoid anteroposterior diameter with bone loss of up to 30%. The majority of female patients have coracoid thickness <10 mm, which may increase the risk of graft fracture when using CAM. The decision to use the classic Latarjet technique or CAM considers each individual's glenoid and coracoid dimensions with a goal of achieving an on-track shoulder. CLINICAL RELEVANCE: Our reliable method of coracoid measurement demonstrated the differing abilities of the classic Latarjet and CAM to restore the native glenoid diameter. An evidence-based algorithm using these measurements was developed to assist in preoperative planning for glenohumeral instability in the setting of bone loss, with a goal of achieving an on-track shoulder. Alternative techniques may be considered if an on-track shoulder cannot be achieved with Latarjet.

How to Address the Medial Patellofemoral Ligament, Tibial Tubercle, and Articular Cartilage in Patients With Recurrent Patellar Instability.

Patellofemoral instability is a common pathology especially in the adolescent female population.1,2 Prompt diagnosis and management is critical to prevent future episodes of instability as well as to reduce the risk of cartilaginous injury to the patellofemoral articular surface. Initial management of a first-time patellar dislocation has historically been nonsurgical; however, the presence of intra-articular loose bodies or osseocartilaginous injury may require surgical intervention.3,4 More recent evidence has shown patients with specific risk factors such as skeletal immaturity, an incompetent medial soft-tissue sleeve, family history of patellar dislocation, elevated tibial tubercle to trochlear groove distance, patella alta, and high-grade trochlear dysplasia experience high rates of re-dislocation after initial nonsurgical management.4-9 Based on this, the provider needs to consider these risk factors and the possibility of initial surgical management in these patient populations following a first-time patellar dislocation. Surgical options for management of patellar instability and cartilaginous injury include medial patellofemoral ligament repair, medial patellofemoral ligament reconstruction, tibial tubercle osteotomy, and various cartilaginous repair/restoration procedures. It is important to be knowledgeable about the clinical and anatomic/radiographic risk factors associated with patients presenting with patellar instability, the algorithm for treatment, the indications and surgical technique for medial patellofemoral ligament reconstruction and tibial tubercle osteotomy, and management of cartilaginous injury to the patellofemoral joint.

The impact of prior ipsilateral arthroscopy on infection rates after shoulder arthroplasty.

BACKGROUND: Patients frequently undergo interventions before shoulder arthroplasty, including injections and arthroscopy. Although the potential impact of injections on postoperative outcomes such as infection has been well studied, it is less clear whether prior arthroscopy has an impact on infection rates after shoulder arthroplasty. The purpose of this study was to determine whether prior ipsilateral shoulder arthroscopy is associated with an increased risk of postoperative infection after shoulder arthroplasty. METHODS: Patients who underwent shoulder arthroplasty, including hemiarthroplasty, total shoulder arthroplasty, or reverse shoulder arthroplasty with a minimum of 1-year preoperative database exposure, were queried using Current Procedural Terminology codes from 2 large insurance databases, including both private-payer (Humana, 2008-2017) and Medicare (2006-2014) data. Patients with procedures for infection, fractures, or without laterality data were excluded. Those who underwent ipsilateral shoulder arthroscopy within 2 years before their arthroplasty were identified and compared with controls who did not undergo prior arthroscopy. Each database was analyzed separately. Periprosthetic infection within 1 year after arthroplasty was queried for each group and compared using a logistic regression analysis with control for demographic and comorbidity confounders. RESULTS: A total of 9362 Medicare patients and 17,716 private-payer patients were included in the study. Of these, 486 (5.2%) Medicare patients and 685 (3.9%) private-payer patients underwent prior arthroscopy. In the Medicare database, prior arthroscopy was also associated with a postarthroplasty infection rate of 3.9% as compared with 1.9% in the control group (odds ratio: 1.96, 95% confidence interval: 1.20-3.22, P = .003). Similarly, in the private insurance cohort, prior shoulder arthroscopy was associated with a postarthroplasty infection rate of 2.9% as compared with 1.4% in the control group (odds ratio: 1.85, 95% confidence interval: 1.13-3.03, P = .005). CONCLUSION: Shoulder arthroscopy performed within 2 years before shoulder arthroplasty is associated with a higher infection rate in the first year after shoulder arthroplasty.

Clinical Outcomes After Biceps Tenodesis or Tenotomy Using Subpectoral Pain to Guide Management in Patients With Rotator Cuff Tears.

PURPOSE: To assess whether preoperative subpectoral tenderness in patients with rotator cuff tears was associated with arthroscopic findings of tendinopathy of the long head of the biceps, as well as whether they had resolution of their subpectoral tenderness postoperatively after tenodesis or tenotomy. METHODS: Patients presenting between 2011 and 2016 undergoing arthroscopic rotator cuff repair were evaluated preoperatively with the subpectoral biceps test (SBT). This test is performed with the arm adducted and internally rotated to allow palpation of the biceps as it courses under the pectoralis major tendon. Preoperative SBT findings determined operative management with either tenodesis or tenotomy during rotator cuff repair. Patients were followed up postoperatively to assess resolution of subpectoral tenderness with a repeated SBT. Preoperative and postoperative Single Assessment Numeric Evaluation (SANE), American Shoulder and Elbow Surgeons, and Constant-Murley scores were recorded in all patients. RESULTS: A total of 128 patients were enrolled in the study, with a mean age of 58 years (range, 33-82 years). Patients with a positive preoperative SBT (n = 68) had significantly lower SANE and Constant-Murley scores preoperatively (P < .01) than patients with a negative SBT (n = 60). All patients with a positive preoperative SBT underwent either tenodesis or tenotomy, with 94% of patients (n = 64) having resolution of subpectoral pain and tenderness at final follow-up. Intraoperatively, 93% of patients with a positive SBT showed gross pathologic changes in the tendon (fraying, erythema, tears, or subluxation) compared with only 65% of patients with negative preoperative examination findings (P < .01). American Shoulder and Elbow Surgeons, Constant-Murley, and SANE scores were significantly increased postoperatively in all patients (P = .02). CONCLUSIONS: In this group of patients with rotator cuff tears surgically treated with concomitant biceps tenodesis or tenotomy, 94% had resolution of their subpectoral tenderness. A positive SBT was associated with gross pathologic changes of the biceps in 93% of patients. LEVEL OF EVIDENCE: Level III, prospective comparative study.

No correlation between radiolucency and biomechanical stability of keeled and pegged glenoid components.

BACKGROUND: The purpose of this study was to examine biomechanical properties and the degree of radiolucency of two cemented basic glenoid designs for total shoulder arthroplasty. Our hypothesis was that a component with increased micro-motion in the laboratory at time zero would also exhibit a greater amount of radiolucency in patients at a minimum of 2 years post total shoulder arthroplasty. METHODS: Thirty cadaveric shoulders were divided into 2 groups (keel vs. peg). The glenoid components were first loaded with a single axial eccentric force of 196 N in all orientations and then with a transversal load of 49 N to simulate in vivo loads with abduction. Displacement of the glenoid component was determined with four different linear variable-differential transducers. In the second phase, 56 antero-posterior x-rays of 52 patients with either the same keeled (n = 24) or pegged (n = 32) glenoid component with a minimum of 24 months follow-up were evaluated for radiolucency. RESULTS: Biomechanically the pegged glenoid showed a significant increase in micro-motion during eccentric axial loading as well as during combined loading in the anterior, posterior, and inferior position as compared to the keeled glenoid (p < 0.05). In contrast all results were significant with greater radiolucency for the keeled glenoid component (p = 0.001). CONCLUSION: While the pegged component exhibited a greater amount of micro-motion during biomechanical testing, radiolucency was greater in patients with a keeled component. These findings provide support for both components from different perspectives and highlight the need for well-constructed studies to determine whether glenoid design has an effect on clinical outcome, because influences are multifactorial and biomechanical forces may not recreate forces seen in vivo.

Open subpectoral biceps tenodesis in patients over 65 does not result in an increased rate of complications.

BACKGROUND: Long head biceps tendon pathology is a common cause of anterior shoulder pain and is often associated with other shoulder conditions, such as rotator cuff tears and osteoarthritis. It is well accepted that older patients are at increased risk for major and minor peri- and postoperative complications. The purpose of this study is to investigate patients over 65 years old who underwent subpectoral biceps tenodesis and compare the complication rates of this group to those of patients younger than 65 years old. The hypothesis is, that there would be no difference in complication rates and that clinical outcome scores for patients over 65 were satisfying and showed improvements over time. METHODS: There were 337 patients who underwent open subpectoral biceps tenodesis, between January 2005 and June 2015, 23 were identified as being over the age of 65 with a minimum follow up of 12 months. All patients over the age of 65 were evaluated pre- and postoperatively using Simple Shoulder Test (SST), American Shoulder and Elbow Surgeons (ASES), Constant-Murley (CM) and Single Assessment Numeric Evaluation (SANE). Intraoperative and postoperative adverse events (fracture, infection, wound opening, rupture/failure and neurovascular injuries) related to the tenodesis procedure and to the surgery itself were collected from all 337 patients in a routine postoperative follow-up. RESULTS: The under 65 group (range 27-64 years) at an average follow up (FU) of 30 months (range 12-91 months) showed a 5.4% (17 out of 314) post-operative complication rate related to the subpectoral tenodesis, whereas the group over 65 (range 65-77 years) at an average follow up of 33 months (range 12-79 months) showed an 8.7% (2 out of 23) complication rate. CONCLUSION: This study demonstrates that in patients over the age of 65, biceps tenodesis is a successful procedure when performed for biceps tendinopathy and concomitantly with other surgical procedures of the shoulder, and does not result in an increased rate of complications when compared to a group of patients under the age of 65.

The Effect of Early Range of Motion on Quality of Life, Clinical Outcome, and Repair Integrity After Arthroscopic Rotator Cuff Repair.

PURPOSE: To compare the effect of early versus delayed motion protocols on quality of life, clinical outcomes, and repair integrity in patients who have undergone arthroscopic single-tendon rotator cuff repair. METHODS: This was a prospective, randomized, investigator-blinded clinical trial. Seventy-three patients from a single surgeon's practice who underwent arthroscopic repair of a single-tendon rotator cuff tear were randomized to either an early motion protocol (starting 2 to 3 days after surgery) or a delayed motion protocol (starting 28 days after surgery). The primary outcome measure was the Western Ontario Rotator Cuff index (WORC). Secondary outcome measures included clinical outcome scores, integrity of the repair on 6-month magnetic resonance imaging scans, pain scores, physical examination data, and ultrasonography. Study participants were followed up at 3, 6, and 12 weeks; 6 months; and 1 year postoperatively. RESULTS: There was no statistically significant difference in WORC scores at 6 months (529 ± 472 in delayed group vs 325 ± 400 in early group, P = .08). Mixed-effects analysis indicated the early group maintained lower WORC scores throughout the postoperative period (estimated difference of 191, P = .04). The proportions of patients with tears on the 6-month postoperative magnetic resonance imaging scan were comparable (31% in delayed group vs 34% in early group, P = .78). CONCLUSIONS: There was no difference between the delayed and early motion groups in WORC scores at 6 months after surgery. Early motion was associated with lower WORC scores throughout the postoperative period; however, both groups had a similar trajectory of improvement, suggesting both protocols have the same effect on patient-reported improvement. Although failure rates were similar between the groups, the sample size was not sufficient to support a statement regarding the relation between tear morphology and the rehabilitation protocol. LEVEL OF EVIDENCE: Level II, lesser-quality randomized controlled trial.

Lateral clavicle fracture with coracoclavicular ligament injury: a biomechanical study of 4 different repair techniques.

PURPOSE: To investigate the biomechanical performance of four different methods used for coracoclavicular (CC) ligament reconstruction in a lateral clavicle fracture repair. METHODS: Native displacement, translation, and rotation at the acromioclavicular joint of 24 fresh-frozen cadaveric shoulders were tested. A reproducible fracture in the lateral third of the clavicle was created by dissecting both CC ligaments. Each specimen was then repaired with plate fixation of the fracture and the following CC repair technique: (1) Cortical button. (2) Suture anchor and plate button. (3) Suture anchor no plate button, and (4) Suture around coracoid. All reconstructed specimens were then re-tested for displacement, translation, and load to failure, and compared to their native results. Groups 1 and 3 were investigated for rotational load. RESULTS: There was no difference in load to failure between the repaired groups (p: ns). Group 1 showed less superior and anterior translations (p < 0.05). Group 2 showed significantly less superior translation (p = 0.003), but no significance with anterior and posterior translations to the native joint. Group 3 showed less superior and posterior translations (p = 0.005 and p = 0.039). Anterior and posterior translations were increased in group 4 (p < 0.05). CONCLUSION: The biomechanical analyses did not show any significance in load to failure or displacement after cyclic loading among the study groups. All repairs were effective in preventing superior translation. Groups 1 and 2 demonstrated increased horizontal stability compared to the native state. All 4 methods are clinically viable options for CC ligament repair.

A Systematic Review of Meta-analyses Published in Arthroscopy: The Journal of Arthroscopic and Related Surgery.

PURPOSE: To determine whether the number of meta-analyses published by Arthroscopy: The Journal of Arthroscopic and Related Surgery has increased from the inception of the Journal through 2014. METHODS: A literature search of the Journal's Web site and Medline was carried out. All studies described as a "meta-analysis" as well as systematic reviews that pooled data were included. The number of published meta-analyses was calculated and summarized by year of publication, region, topic, and level of evidence. RESULTS: The Journal's Web site search resulted in 517 citations for review, and the Medline search resulted in 400. After the results of each search were combined and duplicates were removed, a total of 60 studies were included in this review. The first published meta-analysis appeared in 2001. Of the 60 meta-analyses, 36 (60%) were published between 2013 and 2014. In light of the increase in the number of publications, a review of the design and conduct of a meta-analysis is presented in a straightforward question-and-answer format. CONCLUSIONS: The number of meta-analyses appearing in Arthroscopy has increased over the past 2 decades. This increase highlights the importance of developing an understanding of the premise and components of a meta-analysis to allow the reader to critically appraise these studies. LEVEL OF EVIDENCE: Level IV, systematic review of Level I through IV meta-analyses.

A Biomechanical Analysis of Different Clavicular Tunnel Diameters in Anatomic Acromioclavicular Ligament Reconstruction.

PURPOSE: To evaluate the biomechanical stability of a tendon-to-clavicle bone interface fixation of a graft in revision acromioclavicular reconstruction. METHODS: Fifteen fresh-frozen cadaveric shoulders were used. All specimens underwent bone density evaluation. For the primary reconstruction, a 5-mm semitendinosus allograft was inserted into a 5-mm bone tunnel at 25 and 45 mm from the lateral end of the clavicle using a 5.5 × 8-mm PEEK (polyether ether ketone) tenodesis screw. Each single graft was fixed in a cryo-clamp and cyclically loaded from 5 to 70 N for 3,000 cycles, followed by load-to-failure testing at a rate of 120 mm/min to simulate the revision case. To simulate tunnel widening, the tunnels of the revision series were over-drilled with an 8-mm drill, and a 5-mm semitendinosus graft with an 8 × 12-mm PEEK tenodesis screw was inserted. Biomechanical testing was then repeated. RESULTS: The bone mineral density analysis showed a significantly higher density at the 45-mm hole compared with the 25-mm hole (P = .001). The ultimate load to failure increased from the 5.5-mm screw to the 8-mm screw at the 45-mm hole position (P = .001). There was no statistically significant difference at the 25-mm hole position (P = .934). No statistical significance for graft elongation comparing the 5.5-mm screw and the 8-mm screw at the 25-mm (P = .156) and 45-mm (P = .334) positions could be found. CONCLUSIONS: Comparable biomechanical stability for the tendon-to-bone interface fixation in different clavicular tunnel diameters simulating primary and revision reconstruction was achieved. CLINICAL RELEVANCE: There is a lack of literature regarding revision acromioclavicular joint reconstruction, but our biomechanical results show comparable stability to primary reconstruction. These data provide support for the use of anatomic acromioclavicular ligament reconstruction in revision cases.

Properties of biologic scaffolds and their response to mesenchymal stem cells.

PURPOSE: The purpose of this study was to examine, in vitro, the cellular response of human mesenchymal stem cells (MSCs) to sample types of commercially available scaffolds in comparison with control, native tendon tissue (fresh-frozen rotator cuff tendon allograft). METHODS: MSCs were defined by (1) colony-forming potential; (2) ability to differentiate into tendon, cartilage, bone, and fat tissue; and (3) fluorescence-activated cell sorting analysis (CD73, CD90, CD45). Samples were taken from fresh-frozen human rotator cuff tendon (allograft), human highly cross-linked collagen membrane (Arthroflex; LifeNet Health, Virginia Beach, VA), porcine non-cross-linked collagen membrane (Mucograft; Geistlich Pharma, Lucerne, Switzerland), a human platelet-rich fibrin matrix (PRF-M), and a fibrin matrix based on platelet-rich plasma (ViscoGel; Arthrex, Naples, FL). Cells were counted for adhesion (24 hours), thymidine assay for cell proliferation (96 hours), and live/dead stain for viability (168 hours). Histologic analysis was performed after 21 days, and the unloaded scaffolds were scanned with electron microscopy. RESULTS: MSCs were successfully differentiated into all cell lines. A significantly greater number of cells adhered to both the non-cross-linked porcine collagen scaffold and PRF-M. Cell activity (proliferation) was significantly higher in the non-cross-linked porcine collagen scaffold compared with PRF-M and fibrin matrix based on platelet-rich plasma. There were no significant differences found in the results of the live/dead assay. CONCLUSIONS: Significant differences in the response of human MSCs to biologic scaffolds existed. MSC adhesion, proliferation, and scaffold morphology evaluated by histologic analysis and electron microscopy varied throughout the evaluated types of scaffolds. Non-cross-linked porcine collagen scaffolds showed superior results for cell adhesion and proliferation, as well as on histologic evaluation. CLINICAL RELEVANCE: This study enables the clinician and scientist to choose scaffold materials according to their specific interaction with MSCs.

The effect of number of knots per throw, knot technique, and suture type on strength properties of suspensory fixation button surgical procedures.

Background: Previous studies of the cortical suspensory button (CSB) implant have analyzed fixation strength as a function of suture type and surgical technique, but knot configuration remains an area of interest. This study investigates 4-strand knot configurations in CSB suspensory fixation, specifically comparing the use of 2 separate knots with a single knot. We hypothesize that using 2 knots on the distal side of the CSB with #2 suture will yield the strongest and stiffest suspensory fixation. Methods: Two types of knot configurations were compared: a single knot with all 4 suture strands versus 2 independent knots with 2 suture strands each (1 knot from inner strands and 1 knot from outer strands). They were tested using #2 or 2-0 suture, and at distal (on top of the button) or proximal (underneath the button) knot positions. Mechanical testing on the Instron measured ultimate failure load, elongation at failure, and stiffness. Statistical analyses (Shapiro-Wilk, unpaired Student's t-tests, and Chi-square tests) assessed differences in strength, stiffness, elongation, and failure mode between knot configurations within each CSB construct combination. Results: With #2 suture, 2 knots across the CSB resulted in higher load to failure compared to 1 knot in both proximal (467.00 N vs. 554.66 N, P = .026) and distal (395.18 N vs. 526.51 N, P < .001) locations. Furthermore, 2 knots provided higher stiffness than 1 knot in both proximal (53.24 N/mm vs. 67.89 N/mm, P < .001) and distal (47.08 N/mm vs. 56.73 N/mm, P = .041) knot locations. However, using 2-0 suture showed no significant differences in failure load and stiffness regardless of knot location. Conclusion: Using #2 suture and tying 2 independent knots across the CSB increased load to failure and stiffness compared to using only 1 knot regardless of knot position. Thus, if using #2 suture, it is recommended to tie 2 knots to enhance construct strength. However, with 2-0 suture, the number of knots did not impact construct strength. Therefore, if using 2-0 suture, 1 knot can be used to save time. Knot position did not significantly affect the strength or stiffness of the CSB construct, emphasizing the importance of considering knot prominence and surgical approach for determining knot location.

Knee Flexion Angle of Fixation During Anterolateral Ligament Reconstruction or Lateral Extra-articular Tenodesis: A Systematic Review and Meta-analysis of Lateral Extra-articular Reinforcement Techniques Performed in Conjunction With ACL Reconstruction.

Background: Anterolateral ligament reconstruction (ALLR) or lateral extra-articular tenodesis (LET) is being used more frequently in conjunction with anterior cruciate ligament reconstruction (ACLR). However, the knee flexion angle at which fixation of ALLR or LET is performed during the procedure is quite variable based on existing technique descriptions. Purpose/Hypothesis: The purpose of this study was to identify whether flexion angle at the time of ALLR/LET fixation affected postoperative outcomes in a clinical population. It was hypothesized that ALLR/LET fixation at low versus high flexion angles would lead to no statistically significant differences in patient-reported outcome measures and graft failure rates. Study Design: Systematic review; Level of evidence, 4. Methods: The PubMed, Embase, and Cochrane Library databases were searched according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to identify published clinical studies of ACLR with ALLR/LET in which the knee flexion angle at the time of ALLR/LET was reported. A priori, low flexion was defined as 0° to 30°, and high flexion was defined as 60° to 90°. Studies were excluded if the flexion angle was between 31° and 59° because these angles constituted neither low nor high flexion angles and including them in an analysis of high versus low flexion angle at fixation would have biased the study results toward the null. The overall risk of bias was assessed using the Newcastle-Ottawa Scale. The pooled results of the studies were analyzed using the International Knee Documentation Committee (IKDC), Lysholm, and Tegner scores, along with reported graft failure rates. Results: A total of 32 clinical studies (5230 patients) met inclusion criteria: 22 studies (1999 patients) in the low-flexion group and 10 studies (3231 patients) in the high-flexion group. The median Newcastle-Ottawa Scale score was 6. Comparisons of patients with a low flexion angle versus a high flexion angle demonstrated no differences in the IKDC (P = .84), Lysholm (P = .67), or Tegner (P = .44) scores or in graft failure (3.4% vs 4.1%, respectively; P = .69). Conclusion: The results of this review indicated that ACLR performed in conjunction with ALLR/LET provides good to excellent patient-reported outcomes and low graft failure rates when ALLR/LET fixation is performed in either low or high knee flexion.

An in vitro evaluation of the anti-inflammatory effects of platelet-rich plasma, ketorolac, and methylprednisolone.

PURPOSE: The purpose of this study was to quantify the extent of the anti-inflammatory effect of platelet-rich plasma (PRP) in a controlled in vitro environment. METHODS: Through the stimulation of human umbilical vein endothelial cells with inflammatory cytokines (tumor necrosis factor α and interferon γ), cell adhesion molecule expression (E-selectin, vascular cell adhesion molecule, and human leukocyte antigen DR) and PRP's anti-inflammatory effect can be measured. PRP was produced from 3 individuals using a single-spin (PRPLP) process. Treatment groups include negative (unstimulated) controls, positive (stimulated) controls, ketorolac tromethamine, methylprednisolone, PRP, ketorolac-PRP, and methylprednisolone-PRP. A fluorescence assay of the cellular inflammation markers was measured by the BioTek Synergy HT plate reader (BioTek Instruments, Winooski, VT) at 0, 1, 2, and 5 days. RESULTS: At days 2 and 5, methylprednisolone treatment showed a 2.1- to 5.8-fold reduction (P < .05) in inflammation markers over PRP. In addition, PRP and ketorolac showed a 1.4- to 2.5-fold reduction (P < .05) in cellular inflammation markers over the control. There was no statistically significant difference between ketorolac and PRP. CONCLUSIONS: Although PRP and ketorolac reduced cellular inflammation markers (E-selectin, vascular cell adhesion molecule, and human leukocyte antigen DR) compared with control, neither caused as great a reduction as methylprednisolone. CLINICAL RELEVANCE: Although PRP and ketorolac did not produce as significant a reduction in cellular inflammation markers as methylprednisolone, they reduced cellular inflammation compared with the control. These agents may have clinical application as injectable anti-inflammatory medications.

Graft fixation is highest with anatomic tunnel positioning in acromioclavicular reconstruction.

PURPOSE: The purposes were to determine the bone density at specific bone tunnel locations in the clavicle and to determine ultimate load to failure of a graft fixed with an interference screw at specific areas. METHODS: Bone mass densitometry was tested at 5-mm intervals from the lateral to the medial end of 11 clavicles (mean age, 70.0 ± 17.7 years). Tunnels were drilled in 10-mm increments from the lateral edge, and tenodesis screws were used to fix semitendinosus grafts in the tunnel. Grafts were cyclically loaded, followed by load to failure. RESULTS: The bone mineral density (BMD) of the cadaveric clavicles increased from lateral (0.304 ± 0.078 g/cm(2) at 10 mm) to medial (0.760 ± 0.103 g/cm(2) at 50 mm). Load to failure increased from lateral to medial, and most specimens failed by tendon pullout. The load was 125.3 ± 42.5 N at the most lateral tunnel and 349.3 ± 120.3 N at the most medial tunnel. The Pearson correlation coefficient was 0.653 between tunnel position and load to failure, 0.659 between bone density and load to failure, and 0.803 between tunnel position and bone density. These all showed strong correlation. CONCLUSIONS: BMD shows that optimal bone density is found in the anatomic insertion area of the coracoclavicular ligaments between 20 mm and 50 mm from the lateral end of the clavicle. Low BMD correlated with decreased load to failure. CLINICAL RELEVANCE: Failure at the lateral bone tunnel in coracoclavicular ligament reconstruction may be a result of poor bone quality. When one is drilling bone tunnels for this surgery, consideration should be given to both anatomic position and bone quality.

The future role of mesenchymal stem cells in the management of shoulder disorders.

PURPOSE: Biologics may help to optimize the healing environment after rotator cuff repair. Mesenchymal stem cells (MSCs) may have the potential to regenerate a physiological enthesis, thereby improving healing at the repair site after rotator cuff repair. METHODS: The PubMed database was searched in May 2013. Only in vivo and in vitro studies reporting on stem cell use in the rotator cuff of humans or animals were included. Exclusion criteria consisted of the following: Level V evidence, systematic reviews, and studies reporting preliminary results. RESULTS: This query resulted in 141 citations. Of these, 90 were excluded based on the title of the study. A final group of 17 studies was included in this review (9 in vivo animal studies, 5 in vitro human studies, 1 in vitro animal study, 1 study reporting in vitro human and in vivo animal results, and 1 study reporting on clinical outcomes of human patients). CONCLUSIONS: The current literature regarding therapeutic use of MSCs in shoulder surgery is limited. Although in vivo animal studies have shown some promising approaches to enhance tendon-to-bone healing, the use of MSCs for shoulder surgery should still be regarded as an experimental technique. Further basic and clinical research is needed until a procedure can be defined for the routine use of these cells in shoulder surgery.

The effect of ketorolac tromethamine, methylprednisolone, and platelet-rich plasma on human chondrocyte and tenocyte viability.

PURPOSE: The purpose of this study was to evaluate the effect on cell viability of the isolated and combined use of allogeneic platelet-rich plasma (PRP) and ketorolac tromethamine on human chondrocytes and tenocytes in a highly controlled in vitro environment. METHODS: PRP was produced from 8 subjects. Human chondrocytes (Lonza, Hopkinton, MA) and tenocytes isolated from samples of the long head of the biceps tendons were treated in culture with PRP, ketorolac tromethamine, and methylprednisolone, both alone and in combination. Control samples were treated in media containing 2% or 10% fetal bovine serum (FBS). Cells were exposed for 1 hour. Luminescence assays were obtained to examine cell viability after 24 hours and long-term effects on cell viability after 120 hours. Radioactive thymidine assay was used to measure proliferation after 120 hours. RESULTS: For chondrocytes, cell viability (120 hours) increased significantly with the treatment of PRP alone (43,949 ± 28,104 cells; P < .001) and with the combination of ketorolac tromethamine and PRP (43,276 ± 31,208; P < .001), compared with the 2% FBS group (7,397 ± 470). Cell viability decreased significantly after exposure to methylprednisolone (1,323 ± 776; P < .001) and its combination with PRP (4,381 ± 5,116; p < .001). For tenocytes, cell viability (120 hours) was significantly higher with the treatment of PRP (61,287 ± 23,273; P < .001) and the combined treatment of ketorolac tromethamine and PRP (52,025 ± 17,307; P < .001), compared with the 2% FBS group (23,042 ± 2,973). Cell viability decreased significantly after exposure to methylprednisolone (3,934 ± 1,791; P = .001) and its combination with PRP (5,201 ± 2,834; P = .003), compared with 2% FBS. CONCLUSIONS: Tendon and cartilage cells showed increased cell viability after an exposure to allogeneic PRP and ketorolac tromethamine. Exposure to methylprednisolone alone decreased cell viability, and addition of PRP could partially reverse this negative effect. CLINICAL RELEVANCE: Intra-articular injections of pain-modifying or anti-inflammatory drugs are routinely given in orthopaedic practice. Among the many agents available for intra-articular injection, corticosteroids and local anesthetics are the most common in clinical practice. Potential detrimental side effects of intra-articular injections of corticosteroids and local anesthetics have prompted investigation into alternative treatment options such as combinations of PRP and ketorolac tromethamine. In vitro evaluation of their effect on cell viability might build a basis for further translational research and clinical application.