Biologically Augmented Suture for Ligament Bracing Procedures Positively Affects Human Ligamentocytes and Osteoblasts In Vitro.

PURPOSE: The purpose was to evaluate the response of human ligamentocytes and osteoblasts after biological augmentation with thrombin, concentrated bone marrow aspirate (cBMA), or platelet-rich plasma (PRP) on two different types of nonresorbable flat braided suture used for ligament bracing. METHODS: Uncoated (U) and collagen-coated (C) flat braided suture material was augmented with either thrombin (T), cBMA (B), PRP (P), or a combination of these three (A), while platelet-poor plasma was used as a source for fibrin (F) in each assay. Previously cultured ligamentocytes and osteoblasts were added with a defined density and assayed after the required time period for adhesion, proliferation, and alkaline phosphatase activity. RESULTS: Biological augmentation of uncoated [(UFT, UFBT, UFA; P < .001), (UFPT; P = .017)] and collagen-coated suture (CFT, CFPT, CFBT, CFA; P < .001) led to a significantly higher ligamentocyte adhesion. Significantly higher adhesion was also observed for osteoblasts (UFT, UFPT, UFBT, UFA; P < .001; CFT, CFPT, CFBT, CFA; P < .001). Similarly, ligamentocyte proliferation was significantly higher [(UFT, UFPT, UFA; P = .009), (UFBT; P = .001), (CFT; P = .009), (CFBT; P = .001), and (CFA; P = .01)]. Osteoblasts showed significantly higher proliferation as well [(UFT, UFPT, UFA; P = .002), (UFBT; P = .001); (CFT: P = .003), and (CFPT, CFBT, CFA; P = .001)]. Augmentation with thrombin, PRP, and BMA for uncoated (UFT; P = .006, UFPT; P = .035, UFBT; P = .001) and BMA for coated suture (CFBT; P = .027) led to significantly higher alkaline phosphatase activity. CONCLUSION: Biological enhancement of suture used for ligament bracing significantly increased ligamentocyte and osteoblast adhesion and proliferation, as well as alkaline phosphatase activity of osteoblasts in an in vitro model. After biological augmentation, cellular adhesion, proliferation, and alkaline phosphatase activity changed up to 1,077%, 190%, and 78%, respectively. Furthermore, no overall superiority between uncoated or collagen-coated suture material was observed for cellular adhesion, proliferation, or alkaline phosphatase activity. CLINICAL RELEVANCE: This study provides in vitro data on a new treatment concept of biologic augmentation for acute ligamentous lesions treated with ligament bracing that has not been widely described. This concept may improve the healing of injured ligaments, in addition to providing immediate biomechanical stabilization.

A reduced concentration femoral nerve block is effective for perioperative pain control following ACL reconstruction: a retrospective review.

INTRODUCTION: Femoral nerve block (FNB) is a routinely used regional analgesic technique for anterior cruciate ligament (ACL) reconstruction. One method to balance the analgesic effect and functional impairment of FNBs may be to control the concentration of local anesthetics utilized for the block. MATERIALS AND METHODS: Retrospective chart review was performed on 390 consecutive patients who underwent ACL reconstruction between June 2014 and May 2017. Patients were divided into those who received a standard (0.5%-bupivacaine) or low (0.1-0.125%-bupivacaine) concentration single-shot FNB performed with ultrasound guidance. Maximum postoperative VAS, Post-Anaesthesia Care Unit (PACU) time prior to discharge, need for additional 'rescue' block, and intravenous postoperative narcotic requirements were recorded. RESULTS: A total of 268 patients (28.4 ± 11.9 years) were included for final analysis, with 72 patients in the low-concentration FNB group and 196 patients receiving the standard concentration. There were no differences in the maximum postoperative VAS between the low (6.4 ± 2.5) and standard (5.7 ± 2.9) concentration groups (P = 0.08). Similarly, the time from PACU arrival to discharge was not different between groups (P = 0.64). A sciatic rescue block was needed in 22% of patients with standard-dose FNB compared to 30% of patients receiving the low-concentration FNB (P = 0.20). Patients with a hamstring autograft harvest were more likely to undergo a postoperative sciatic rescue block compared to a bone-patellar tendon autograft (P = 0.005), regardless of preoperative block concentration. Quadriceps activation was preserved with low-concentration blocks. CONCLUSIONS: Using 1/5th to 1/4th the standard local anesthetic concentration for preoperative femoral nerve block in ACL reconstruction did not significantly differ in peri-operative outcomes, PACU time, need for rescue blockade, or additional immediate opioid requirements. LEVEL OF EVIDENCE: III.

Clinical Outcomes Following Biologically Enhanced Patch Augmentation Repair as a Salvage Procedure for Revision Massive Rotator Cuff Tears.

PURPOSE: To evaluate the clinical outcomes of patients who underwent biologically enhanced patch augmentation repair for the treatment of revision massive rotator cuff tears. METHODS: Twenty-two patients who underwent arthroscopic and mini-open rotator cuff repair using a patch augmented with platelet-rich plasma and concentrated bone marrow aspirate (cBMA) for revision massive (≥2 tendons) rotator cuff tears from 2009 to 2014, with a minimum 1-year follow-up, were included in the study. In this procedure the medial side of the graft is secured to the rotator cuff tendon remaining medially. American Shoulder and Elbow Surgeons (ASES), Simple Shoulder Test, and postoperative Single Assessment Numerical Evaluation scores were evaluated. To determine the clinical relevance of ASES scores, the minimal clinically important difference, substantial clinical benefit (SCB), and the patient-acceptable symptomatic state (PASS) thresholds were used. Clinical success or failure was defined based on whether the patient reached the SCB threshold. In the laboratory, cellular counting along with the concentration of connective tissue progenitor cells were performed on patch samples from the day of surgery. Scaffolds were processed histologically at days 0, 7,14, and 21 of culture. RESULTS: Patients had significant improvement in the Simple Shoulder Test (2.6 ± 3.0pre vs 5.2 ± 4.2post, P = .01), whereas improvement in pain scores was found to be nonsignificant (5.6 ± 2.5pre vs 4.2 ± 3.4post,P = .11) at final follow-up. Mean ASES improved by Δ14.6 ± 33.4 points; however, this did not reach statistical significance (40.2 ± 21.6pre vs 53.9 ± 31.4post,P = .10). With regards to ASES score, 45% of patients achieved the minimal clinically important difference, 41% the SCB, and 32% reached or exceeded the PASS criteria. At 21 days, there was a significantly greater cell count in scaffolds from patients who had clinical success than those who were failures (P = .02). CONCLUSIONS: Only 41% of patients undergoing biologically enhanced patch augmentation repair reached substantial clinical benefit, whereas 32% reached or exceeded the PASS criteria. LEVEL OF EVIDENCE: Case Series: Level IV.

High Clinical Failure Rate After Latissimus Dorsi Transfer for Revision Massive Rotator Cuff Tears.

PURPOSE: To evaluate the clinical success rate, along with risk factors for failure, in patients undergoing latissimus dorsi transfer for the treatment of massive, irreparable, previously failed rotator cuff tears. METHODS: We performed a retrospective chart review of prospectively collected data from an institutional shoulder outcome registry. All patients who underwent latissimus dorsi transfer for previously failed rotator cuff repair between 2006 and 2013 with a minimum follow-up period of 1 year were included in the study. The indications for inclusion were large (≥2 tendons), retracted, chronic rotator cuff tears with fatty infiltration or atrophy for which prior surgical repair had failed. Preoperative and postoperative American Shoulder and Elbow Surgeons (ASES) and Simple Shoulder Test scores were collected, along with postoperative Single Assessment Numerical Evaluation scores. Complications and clinical failures (Δ in ASES score <17) were recorded. Patient demographic and tear characteristics were evaluated as potential risk factors for failure. RESULTS: A total of 22 patients (mean age, 53 ± 6 years) were included in the study, with a mean follow-up time of 3.4 ± 1.1 years. Over 63% of patients (n = 14) reported undergoing 2 or more prior failed rotator cuff repairs. Patients undergoing latissimus dorsi transfer showed significant improvements in ASES scores (from 35.2 ± 21.9 preoperatively to 55.8 ± 22.9 postoperatively, P = .001), Simple Shoulder Test scores (from 3.5 ± 3.1 preoperatively to 5.2 ± 3.4 postoperatively, P = .002), and pain scores (from 5.9 ± 2.8 preoperatively to 4.6 ± 4.3 postoperatively, P = .002) at final follow-up. The complication rate after latissimus transfer was 27%. The rate of revision to reverse total shoulder arthroplasty was 13.6% (n = 3) after a mean of 2.7 years, and the clinical failure rate was 41% (n = 9) at final follow-up. An acromiohumeral interval of less than 7 mm (P = .04) and high-grade fatty infiltration (grade 3 or greater, P = .004) were significant preoperative risk factors for clinical failure. CONCLUSIONS: Latissimus dorsi tendon transfer resulted in a clinical failure rate of 41% and complication rate of 27%, with an acromiohumeral interval of less than 7 mm and high-grade fatty infiltration being associated with postoperative failure. LEVEL OF EVIDENCE: Level IV.

Osseous valgus alignment and posteromedial ligament complex deficiency lead to increased ACL graft forces.

PURPOSE: To biomechanically investigate the influence of osseous valgus alignment, with and without deficiency of the posteromedial ligament complex (PMC), on ACL-graft forces under axial load. METHODS: ACL reconstruction was performed on ten cadaveric knee joints. A lateral distal femur osteotomy was then done to adjust for three different alignment conditions according to the position, where the axial weight bearing line (WBL) dissected the tibial plateau (% from medial to lateral): 50%, 85% and 115%. Each alignment was tested with the PMC intact, deficient and reconstructed. Axial loads of 400 N were applied in 15° of knee flexion and changes of ACL-graft forces and dynamic valgus angle (DVA) were recorded. RESULTS: In the PMC intact state, lateralization of the WBL to 85% and to 115% led to significantly increased ACL graft forces (85%: p = 0.010; 115%: p < 0.001) and DVAs (85%: p = 0.027; 115%: p = 0.027). Dissection of the PMC led to a significant increase of ACL graft forces and DVAs at 85% and 115% valgus alignment (p < 0.001) only. In comparison to valgus aligned knees with additional PMC deficiency, ligament reconstruction alone was able to significantly decrease ACL graft forces (p < 0.001) and DVAs (p < 0.001). However, alignment correction alone was significantly more effective in reducing ACL graft forces (p < 0.001) and DVAs (p = 0.010). CONCLUSION: Osseous valgus alignment led to significantly increased forces on ACL grafts under axial joint compression, which was even further enhanced, when the PMC was deficient. In the valgus aligned and PMC deficient knee, correction to a straight leg axis was significantly more effective in decreasing forces on the ACL graft than reconstruction of the PMC. In patients with valgus alignment and combined injuries of the ACL and PMC, a correction osteotomy to a straight leg axis as well as reconstruction of the PMC should be considered to protect the reconstructed ACL.

Decision making in treatment after a first-time anterior glenohumeral dislocation: A Delphi approach by the Neer Circle of the American Shoulder and Elbow Surgeons.

BACKGROUND: The treatment of patients who sustain a first-time anterior glenohumeral dislocation (FTAGD) is controversial. The purpose of this study was to find consensus among experts using a validated iterative process in the treatment of patients after an FTAGD. METHODS: The Neer Circle is an organization of shoulder experts recognized for their service to the American Shoulder and Elbow Surgeons. Consensus among 72 identified experts from this group was sought with a series of surveys using the Delphi process. The first survey used open-ended questions designed to identify patient-related features that influence treatment decisions after an FTAGD. The second survey used a Likert scale to rank each feature's impact on treatment decisions. The third survey used highly impactful features to construct 162 clinical scenarios. For each scenario, experts recommended surgery or not and reported how strongly they made their recommendation. These data were analyzed to find clinical scenarios that had >90% consensus for recommending treatment. These data were also used in univariate and multivariate mixed-effects models to identify odds ratios (ORs) for different features and to assess how combining these features influenced the probability of surgery for specific populations. RESULTS: Of the 162 scenarios, 8 (5%) achieved >90% consensus for recommending surgery. All of these scenarios treated athletes with meaningful bone loss at the end of their season. In particular, for contact athletes aged > 14 years who were at the end of the season and had apprehension and meaningful bone loss, there was >90% consensus for recommending surgery after an FTAGD, with surgeons feeling very strongly about this recommendation. Of the scenarios, 22 (14%) reached >90% consensus for recommending nonoperative treatment. All of these scenarios lacked meaningful bone loss. In particular, surgeons felt very strongly about recommending nonoperative treatment after an FTAGD for non-athletes lacking apprehension without meaningful bone loss. The presence of meaningful bone loss (OR, 6.85; 95% confidence interval, 6.24-7.52) and apprehension (OR, 5.60; 95% confidence interval, 5.03-6.25) were the strongest predictors of surgery. When these 2 features were combined, profound effects increasing the probability of surgery for different populations (active-duty military, non-athletes, noncontact athletes, and contact athletes) were noted, particularly non-athletes. CONCLUSION: Consensus for recommending treatment of the FTAGD patient was not easily achieved. Certain combinations of patient-specific factors, such as the presence of meaningful bone loss and apprehension, increased the probability of surgery after an FTAGD in all populations. Over 90% of shoulder instability experts recommend surgery after an FTAGD for contact athletes aged > 14 years at the end of the season with both apprehension and meaningful bone loss. Over 90% of experts would not perform surgery after a first dislocation in patients who are not athletes and who lack apprehension without meaningful bone loss.

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.

Slope-reducing tibial osteotomy decreases ACL-graft forces and anterior tibial translation under axial load.

PURPOSE: Posterior tibial slope (PTS) represents an important risk factor for anterior cruciate ligament (ACL) graft failure, as seen in clinical studies. An anterior closing wedge osteotomy for slope reduction was performed to investigate the effect on ACL-graft forces and femoro-tibial kinematics in an ACL-deficient and ACL-reconstructed knee in a biomechanical setup. METHODS: Ten cadaveric knees with a relatively high native slope (mean ± SD): (slope 10° ± 1.4°, age 48.2 years ± 5.8) were selected based on prior CT measurements. A 10° anterior closing-wedge osteotomy was fixed with an external fixator in the ACL-deficient and ACL-reconstructed knee (quadruple Semi-T/Gracilis-allograft). Each condition was randomly tested with both the native tibial slope and the post-osteotomy reduced slope. Axial loads (200 N, 400 N), anterior tibial draw (134 N), and combined loads were applied to the tibia while mounted on a free moving and rotating X-Y table. Throughout testing, 3D motion tracking captured anterior tibial translation (ATT) and internal tibial rotation (ITR). Change of forces on the reconstructed ACL-graft (via an attached load-cell) were recorded, as well. RESULTS: ATT was significantly decreased after slope reduction in the ACL-deficient knee by 4.3 mm ± 3.6 (p < 0.001) at 200 N and 6.2 mm ± 4.3 (p < 0.001) at 400N of axial load. An increase of ITR of 2.3° ±2.8 (p < 0.001) at 200 N and by 4.0° ±4.1 (p < 0.001) at 400 N was observed after the osteotomy. In the ACL-reconstructed knee, ACL-graft forces decreased after slope reduction osteotomy by a mean of 14.7 N ± 9.8 (p < 0.001) at 200 N and 33.8 N ± 16.3 (p < 0.001) at 400N axial load, which equaled a relative decrease by a mean of 17.0% (SD ± 9.8%), and 33.1% (SD ± 18.1%), respectively. ATT and ITR were not significantly changed in the ACL-reconstructed knee. Testing of a tibial anterior drawing force in the ACL-deficient knee led to a significantly increased ATT by 2.7 mm ± 3.6 (p < 0.001) after the osteotomy. The ACL-reconstructed knee did not show a significant change (n.s.) in ATT after the osteotomy. However, ACL-graft forces detected a significant increase by 13.0 N ± 8.3 (p < 0.001) after the osteotomy with a tibial anterior drawer force, whereas the additional axial loading reduced this difference due to the osteotomy (5.3 N ± 12.6 (n.s.)). CONCLUSIONS: Slope-reducing osteotomy decreased anterior tibial translation in the ACL-deficient and ACL-reconstructed knee under axial load, while internal rotation of the tibia increased in the ACL-deficient status after osteotomy. Especially in ACL revision surgery, the osteotomy protects the reconstructed ACL with significantly lower forces on the graft under axial load.

Glenoid retroversion is an important factor for humeral head centration and the biomechanics of posterior shoulder stability.

PURPOSE: Glenoid retroversion is a known independent risk factor for recurrent posterior instability. The purpose was to investigate progressive angles of glenoid retroversion and their influence on humeral head centration and posterior translation with intact, detached, and repaired posterior labrum in a cadaveric human shoulder model. METHODS: A total of 10 fresh-frozen human cadaveric shoulders were investigated for this study. After CT- canning, the glenoids were aligned parallel to the floor, with the capsule intact, and the humerus was fixed in 60° of abduction and neutral rotation. Version of the glenoid was created after wedge resection from posterior and fixed with an external fixator throughout the testing. Specimens underwent three conditions: intact, detached, and repaired posterior labrum, while version of the glenoid was set from + 5° anteversion to - 25° retroversion by 5° increments. Within the biomechanical setup, the glenohumeral joint was axially loaded (22 N) to center the joint. At 0° of glenoid version and intact labrum, the initial position was used as baseline and served as point zero of centerization. After cyclic preloading, posterior translation force (20 N) was then applied by a material testing machine, while start and endpoints of the scapula placed on an X-Y table were measured. RESULTS: The decentralization of the humeral head at glenoid version angles of 5°, 10°, 15°, and 20° of retroversion and 5° of anteversion was significantly different (P < 0.001). Every increment of 5° of retroversion led to an additional decentralization of the humeral head overall by (average ± SD) 2.0 mm ± 0.3 in the intact and 2.0 mm ± 0.7 in the detached labrum condition. The repaired showed significantly lower posterior translation compared to the intact condition at 10° (P = 0.012) and 15° (P < 0.01) of retroversion. In addition, CT measured parameters (depth, diameter, and native version) of the glenoid showed no correlation with angle of dislocation of each specimen. CONCLUSION: Bony alignment in terms of glenoid retroversion angle plays an important role in joint centration and posterior translation, especially in retroversion angles greater than 10°. Isolated posterior labrum repair has a significant effect on posterior translation in glenoid retroversion angles of 5° and 10°. Bony correction of glenoid version may be considered to address posterior shoulder instability with retroversion > 15°.

Single cut distal femoral osteotomy for correction of femoral torsion and valgus malformity in patellofemoral malalignment - proof of application of new trigonometrical calculations and 3D-printed cutting guides.

BACKGROUND: The purpose of this study was to perform a derotational osteotomy at the distal femur, as is done in cases of patellofemoral instability, and demonstrate the predictability of three-dimensional (3D) changes on axes in a cadaveric model by the use of a new mathematical approach. METHODS: Ten human cadaveric femurs, with increased antetorsion, underwent a visually observed derotational osteotomy at the distal femur by 20°, as is commonly done in clinics. For surgery, a single cut osteotomy with a defined cutting angle was calculated and given using a simple 3D-printed cutting guide per specimen, based on a newly-created trigonometrical model. To simulate post-operative straight frontal alignment in a normal range, a goal for the mechanical lateral distal femur angle (mLDFA) was set to 87.0° for five specimens (87-goal group) and 90.0° for five specimens (90-goal group). Specimens underwent pre- and post-operative radiographic analysis with CT scan for torsion and frontal plane x-ray for alignment measurements of mLDFA and anatomical mechanical angle (AMA). RESULTS: Performed derotation showed a mean of 19.69° ±1.08°SD (95% CI: 18.91° to 20.47°). Regarding frontal alignment, a mean mLDFA of 86.9° ±0.66°SD (87-goal-group) and 90.42° ±0.25° SD (90-goal group), was observed (p = 0.008). Overall, the mean difference between intended mLDFA-goal and post-operatively achieved mLDFA was 0.14° ±0.56° SD (95% CI: -0.26° to 0.54°). CONCLUSION: A preoperative calculated angle for single cut derotational osteotomy at the distal femur leads to a clinically precise post-operative result on torsion and frontal alignment when using this approach.

Higher Critical Shoulder Angle and Acromion Index Are Associated With Increased Retear Risk After Isolated Supraspinatus Tendon Repair at Short-Term Follow Up.

PURPOSE: To evaluate the effect of critical shoulder angle (CSA), acromion index (AI), and glenoid inclination (GI) on the postoperative healing rate after arthroscopic supraspinatus tendon repair. METHODS: Patients after arthroscopic repair of a symptomatic, unilateral, single-tendon, full-thickness supraspinatus tear in whom nonoperative management had failed were retrospectively reviewed. Magnetic resonance imaging (MRI) studies were obtained 6 months postoperatively and were evaluated by 2 independent observers. Repair integrity was classified as either intact or torn. Preoperative true anteroposterior radiographs were used to measure CSA, AI, and GI. RESULTS: Fifty-seven patients were evaluated 6 months postoperatively. The mean patient age at surgery was 54.7 ± 7.7 years. On MRI studies, 41 patients (71.9%) had an intact repair and 16 patients (28.1%) had a full-thickness retear. There were no significant differences between the intact and retear group in regard to patient age (P = .648), initial tear size (P = .205), or fatty degeneration (P = .508). The mean CSA for the retear group (37° ± 4°) was significantly higher than that in the intact group (35° ± 3°; P = .014). If the CSA was >38°, the odds ratio of having a retear was 3.78 (95% confidence interval 1.05 to 13.58; P = .042). Average AI for the retear group (0.73 ± 0.09) was significantly higher than that in the intact group (0.69 ± 0.06; P = .049). The mean GI was 17° ± 6° for the intact group and 16° ± 6° for the retear group (P = .739). CONCLUSIONS: At short-term follow-up, higher CSA and AI significantly increased the retear risk after arthroscopic supraspinatus tendon repair. CSA >38° increased the retear risk almost 4-fold. Overall GI was elevated but did not correlate with failure rate. LEVEL OF EVIDENCE: III, case control study.

Shoulder Instability: An American Perspective.

The recognition and management of glenohumeral instability has become an increasingly important aspect of orthopaedic care. Substantial controversy exists with regard to the indications for soft-tissue stabilization versus bony augmentation in patients with glenohumeral instability, particularly among surgeons in the United States and Europe. Although bone loss procedures are frequently performed in the United States and abroad, surgical techniques and indications for bone loss procedures are different. Surgeons should understand current evidence-based indications for arthroscopic versus open soft-tissue stabilization in patients with anterior shoulder instability. Surgeons also should understand the importance of glenoid bone loss with regard to surgical decision making and the indications for Latarjet reconstruction versus allograft reconstruction. Patient-specific factors, including age, sex, sports participation (type and level of play), and the number of instability events that occur before presentation, affect surgical decision making. The technical pearls for successful arthroscopic stabilization, remplissage, open soft-tissue stabilization, and bony reconstruction of the glenoid rim that are discussed in this chapter may increase the likelihood of successful outcomes in patients with glenohumeral instability.

How to avoid unintended valgus alignment in distal femoral derotational osteotomy for treatment of femoral torsional malalignment - a concept study.

BACKGROUND: Defining the optimal cutting plane for derotational osteotomy at the distal femur for correction of torsion in cases of patellofemoral instability is still challenging. This preliminary study investigates changes of frontal alignment by a simplified trigonometrical model and demonstrates a surgical guidance technique with the use of femur cadavers. The hypothesis was that regardless of midshaft bowing, a cutting plane perpendicular to the virtual anatomic shaft axis avoids unintended valgus malalignment due to derotation. METHODS: A novel mathematical model, called the Pillar-Crane-Model, was developed to forecast changes on frontal alignment of the femur when a perpendicular cutting plane to the virtual anatomical shaft was chosen. As proof of concept, eight different torsion angles were assessed on two human cadaver femora (left and right). A single cut distal femoral osteotomy perpendicular to the virtual anatomical shaft was performed. Frontal plane alignment (mLDFA, aLDFA, AMA) was radiographically analyzed before and after rotation by 0°, 10°, 20°, and 30°. Measurements were compared to the model. RESULTS: The trigonometrical equation from the Pillar-Crane-Model provides mathematical proof that slight changes into varus occur, seen by an increase in AMA and mLDFA, when the cutting plane is perpendicular to the virtual anatomical shaft axis. A table with standardized values is provided. Exemplarily, the specimens showed a mean increase of AMA from 4.8° to 6.3° and mLDFA from 85.2° to 86.7 after derotation by 30°. Throughout the derotation procedure, aLDFA remained at 80.4° ± 0.4°SD. CONCLUSIONS: With the use of this model for surgical guidance and anatomic reference, unintended valgus changes on frontal malalignment can be avoided. When the cutting plane is considered to be perpendicular to the virtual anatomical shaft from a frontal and lateral view, a slight increase of mLDFA results when a derotational osteotomy of the distal femur is performed.

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.

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.

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.

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.

Current concepts in the treatment of acromioclavicular joint dislocations.

PURPOSE: To conduct a systematic review of the literature in relation to 3 considerations in determining treatment options for patients with acromioclavicular (AC) joint dislocations: (1) operative versus nonoperative management, (2) early versus delayed surgical intervention, and (3) anatomic versus nonanatomic techniques. METHODS: The PubMed database was searched in October 2011 using the single term acromioclavicular and the following search limits: any date, humans, English, and all adult (19+). Studies were included if they compared operative with nonoperative treatment, early with delayed surgical intervention, or anatomic with nonanatomic surgical techniques. Exclusion criteria consisted of the following: Level V evidence, laboratory studies, radiographic studies, biomechanical studies, fractures or revisions, meta-analyses, and studies reporting preliminary results. RESULTS: This query resulted in 821 citations. Of these, 617 were excluded based on the title of the study. The abstracts and articles were reviewed, which resulted in the final group of 20 studies that consisted of 14 comparing operative with nonoperative treatment, 4 comparing early with delayed surgical intervention, and 2 comparing anatomic with nonanatomic surgical techniques. The lack of higher level evidence prompted review of previously excluded studies in an effort to explore patterns of publication related to operative treatment of the AC joint. This review identified 120 studies describing 162 techniques for operative reconstruction of the AC joint. CONCLUSIONS: There is a lack of evidence to support treatment options for patients with AC joint dislocations. Although there is a general consensus for nonoperative treatment of Rockwood type I and II lesions, initial nonsurgical treatment of type III lesions, and operative intervention for Rockwood type IV to VI lesions, further research is needed to determine if differences exist regarding early versus delayed surgical intervention and anatomic versus nonanatomic surgical techniques in the treatment of patients with AC joint dislocations. LEVEL OF EVIDENCE: Level III, systematic review of Level II and Level III studies and one case series.