Biologic Adjuvants to Rotator Cuff Repairs Induce Anti-Inflammatory Macrophage 2 Polarization and Reduce Inflammatory Macrophage 1 Polarization In Vitro.

PURPOSE: To examine the effect of various biologic adjuvants on the polarization of macrophages in an in vitro model for rotator cuff tears. METHODS: Tissue was harvested from 6 patients undergoing arthroscopic rotator cuff repair. An in vitro model of the supraspinatus and subacromial bursa was created and treated with control, platelet rich plasma (PRP), autologous activated serum (AAS), or a combination of PRP+AAS. The effect of treatment on macrophage polarization between M1 pro-inflammatory macrophages or M2 anti-inflammatory macrophages was measured using gene expression, protein expression, flow cytometry and nitric oxide (NO) production. RESULTS: Tendon and bursa treated with PRP, AAS and PRP+AAS significantly decreased the gene expression of M1 markers IL-12 and TNF-a, while significantly increasing the expression of M2 markers Arginase, IL-10 and TGF-b (p<0.05) compared to treatment with control. ELISA analysis of protein production demonstrated that compared to control, co-culture treated with PRP, AAS and PRP+AAS significantly decreased markers of M1-macrophages (IL-6, IL-12, and TNF-a), while significantly increasing the expression of markers of M2-macrophages (Arginase, IL-10, and TGF-b) (p<0.05). Flow cytometry analysis of surface markers demonstrated that compared to control, tendon and bursa treated with PRP, AAS and PRP+AAS significantly decreased markers of M1-macrophages (CD80, CD86, CD64, CD16), while significantly increasing the expression of markers of M2-macrophages (CD163 and CD206) (p<0.05). Treatment of the co-culture with PRP, AAS and PRP+AAS consistently demonstrated a decrease in NO production (p<0.05) compared to control. AAS and PRP+AAS demonstrated an increased macrophage shift to M2 compared to PRP alone, whereas there was not as uniform of a shift when comparing PRP+AAS to AAS alone. CONCLUSIONS: In an in vitro model of rotator cuff tears, the treatment of supraspinatus tendon and subacromial bursa with PRP, AAS and PRP+AAS demonstrated an increase in markers of anti-inflammatory M2-macrophages and a concomitant decrease in markers of pro-inflammatory M1-macrophages. AAS and PRP+AAS contributed to a large shift to macrophage polarization to the anti-inflammatory M2 compared to PRP.

Getting Athletes Back on the Field: Management of Clavicle Fractures and Return to Play.

This chapter provides an overview of the prevalence of clavicle fractures in athletes. The evaluation and management of clavicle fractures in athletes is summarized, including surgical considerations, rehabilitation protocols, and return to sport guidelines. In this population, high rates of union are observed, but careful timing of return to sport is paramount to optimize performance and prevent reinjury.

Atraumatic Sternoclavicular Joint Instability: Prevalence, Etiology, and Management.

Sternoclavicular joint instability is a rare complaint in the orthopedic clinic, but patients can experience chronic pain and functional impacts. Causes of instability may be posttraumatic, infectious, autoimmune, degenerative, or secondary to generalized laxity. Conservative treatment is the initial approach to management and involves activity modification, physical therapy, oral nonsteroidal anti-inflammatory drugs, and corticosteroid injections. Surgery is indicated when conservative treatment does not manage symptoms. Figure-of-eight reconstruction techniques provide greatest biomechanical strength but are associated with risk of neurovascular injury. Other reconstruction methods have been shown to mitigate these risks with favorable short-term outcomes.

Anterior Bankart Repair With Superior Capsular Plication Causes Increased Mean Tension in Posterior Glenohumeral Capsule.

Purpose: The purpose of this study is to investigate if a biomechanical difference exists in the prerepair and postrepair states of the posterior inferior glenohumeral ligament (PIGHL) following anterior Bankart repair with respect to capsular tension, labral height, and capsular shift. Methods: In this study, 12 cadaveric shoulders were dissected to the glenohumeral capsule and disarticulated. The specimens were loaded to 5-mm displacement using a custom shoulder simulator, and measurements were taken for posterior capsular tension, labral height, and capsular shift. We measured the capsular tension, labral height, and capsular shift of the PIGHL in its native state and following repair of a simulated anterior Bankart lesion. Results: We found that there was a significant increase in the mean capsular tension of the posterior inferior glenohumeral ligament (Δ = 2.12 ± 2.10 N; P = .005), as well as posterior capsular shift (Δ = .362 ± 0.365 mm; P = .018). There was no significant change in posterior labral height (Δ = 0.297 ± 0.667 mm; P = .193). These results demonstrate the sling effect of the inferior glenohumeral ligament. Conclusion: Although the posterior inferior glenohumeral ligament is not directly manipulated during an anterior Bankart repair, when the anterior inferior glenohumeral ligament is plicated superiorly, some of the tension is transmitted to the posterior glenohumeral ligament as a result of the sling effect. Clinical Relevance: Anterior Bankart repair with superior capsular plication results in an increased mean tension of the PIGHL. Clinically, this may contribute to shoulder stability.

Ability to Retension Knotless Suture Anchors: A Biomechanical Analysis of Simulated Bankart Lesions.

Background: Knotless suture anchors are gaining popularity in arthroscopic glenohumeral labral repairs. The ability to retension knotless designs after initial anchor placement has been reported; however, no studies have quantified this claim or investigated the biomechanical consequence of retensioning. Purpose/Hypothesis: To determine whether knotless and knotted suture anchors have biomechanical or anatomic differences with regard to labral repairs and to determine whether retensioning of knotless suture anchors affects capsular tension, labral height, and capsular shift. We hypothesized that retensioning of knotless anchors would result in improved capsular tension compared with conventional knotted suture anchors. Study Design: Controlled laboratory study. Methods: A total of 18 fresh-frozen cadaveric shoulders with a mean age of 56 years were dissected to the capsule and disarticulated at the humeral capsular insertion. The scapula was potted and placed in a custom shoulder simulator to tension the capsule via braided sutures localized to the anteroinferior glenohumeral ligament. Specimens were randomized into 3 groups: (1) Knotted (KT), (2) Knotless with end retensioning (KLend), and (3) Knotless with stepwise retensioning (KLstepwise). All repairs were completed using all-suture anchors placed at the 5-, 4-, and 3-o'clock positions. KLstepwise was used to simulate an intraoperative technique. Resultant mean capsular tension under 5 mm of displacement (subfailure loading) was measured for each anchor placement and retensioning step. Labral height and capsular shift were measured using a MicroScribe digitizer. Results: The intact, defect, 1-anchor, 2-anchor, and 3-anchor tensions were not significantly different between the KT and KLend groups. For the latter, retensioning of all knotless anchors increased capsular tension by 2.1 N compared with its 3-anchor state, although this was not statistically significant (P = .081). The KLstepwise group explored an alternative method to retension the capsule using knotless anchors, with similar final capsular tensions compared with the other groups. All repairs had similar improvements in capsulolabral height and superior capsular shift. Conclusion: Knotted and knotless suture anchors provided similar overall restorations in anteroinferior glenohumeral ligament tension. However, knotless devices were capable of small but statistically insignificant improvements in capsular tension with retensioning. Clinical Relevance: Retensioning of knotless anchors allows the surgeon to tighten regions of the glenohumeral capsule that remain lax after repair.

Demographic Factors Associated With an Increased Incidence of Intra-articular Injuries After Delayed Anterior Cruciate Ligament Reconstruction.

Background: Delays from the time of an anterior cruciate ligament (ACL) tear to surgical reconstruction are associated with an increased incidence of meniscal and chondral injuries. Purpose: To evaluate the association between delays in ACL reconstruction (ACLR) and risk factors for intra-articular injuries across 8 patient demographic subsets. Study Design: Cross-sectional study; Level of evidence, 3. Methods: We performed a retrospective chart review of all patients who underwent ACLR from January 2009 to May 2015 at a single institution. Variables collected were age, sex, body mass index, time from injury to surgery, and presence of meniscal tears and chondral injuries. Demographic subsets were created according to sex, age (<27 vs ≥27 years), body mass index (<25 vs ≥25 kg/m2), and injury setting (sports vs non-sports related). Subsets were divided by time from injury to ACLR: 0 to <6 months (control group), 6 to <12 months, and ≥12 months. Multivariate logistic regression-generated odds ratios (ORs) were calculated. Results: Overall, 410 patients were included. ORs were significant for an increased incidence of medial meniscal tears (MMTs) (OR, 1.12-3.72; P = .02), medial femoral condyle (MFC) injuries (OR, 1.18-4.81; P = .02), and medial tibial plateau (MTP) injuries (OR, 1.33-31.07; P = .02) with surgical delays of 6 to <12 months. With ≥12-month delays, significance was found for MMTs (OR, 2.92-8.64; P < .001), MFC injuries (OR, 1.86-5.88; P < .001), MTP injuries (OR, 1.37-21.22; P = .02), lateral femoral condyle injuries (OR, 2.41-14.94; P < .001), and lateral tibial plateau injuries (OR, 1.15-5.27; P = .02). In the subset analysis, differences in the timing, location, rate, and pattern of chondral and meniscal injuries became evident. Female patients and patients with non-sports-related ACL tears had less risk of associated injuries with delayed surgery, while other demographic groups showed an increased injury risk. Conclusion: When analyzing patients who were symptomatic enough to eventually require surgery, an increased incidence of MMTs and medial chondral injuries was associated with ≥6-month delays in ACLR, and an increased incidence of lateral chondral injuries was associated with ≥12-month delays. Female patients and patients with non-sports-related ACL tears had less risk of injuries with delayed ACLR.

Radiographic Appearance of Cosmetic Gluteal Injections in a Patient With Proximal Hamstring Tear: A Case Report.

CASE: A 45-year-old woman presented 6 months after a right proximal hamstring repair with worsening pain over her surgical site. Anterior-posterior pelvis x-rays revealed bilateral soft-tissue densities around the hips. Extensive workup revealed no medical basis for the radiographic appearance. It was discovered that the patient's cosmetic gluteal injections were, in fact, the cause. Follow-up x-rays revealed near-complete resolution of the densities 8 months later. CONCLUSIONS: We present this case to highlight the need to consider cosmetic injections as a potential cause of abnormal radiographic soft-tissue densities in the absence of other clear medical explanations in patients who present with musculoskeletal complaints.

Medial meniscal extrusion greater than 4 mm reduces medial tibiofemoral compartment contact area: a biomechanical analysis of tibiofemoral contact area and pressures with varying amounts of meniscal extrusion.

PURPOSE: The primary objective of this study is to evaluate the contact areas, contact pressures, and peak pressures in the medial compartment of the knee in six sequential testing conditions. The secondary objective is to establish how much the medial meniscus is able to extrude, secondary to soft tissue injury while keeping its roots intact. METHODS: Ten cadaveric knees were dissected and tested in six conditions: (1) intact meniscus, (2) 2 mm extrusion, (3) 3 mm extrusion, (4) 4 mm extrusion, (5) maximum extrusion, (6) capsular based meniscal repair. Knees were loaded with a 1000-N axial compressive force at 0°, 30°, 60°, and 90° for each condition. Medial compartment contact area, average contact pressure, and peak contact pressure data were recorded. RESULTS: When compared to the intact state, there was no statistically significant difference in medial compartment contact area at 2 mm of extrusion or 3 mm of extrusion (n.s.). There was a statistically significant decrease in contact area compared to the intact state at 4 mm (p = 0.015) and maximum extrusion (p < 0.001). The repair state was able to improve medial compartment contact area, and there was no statistically significant difference between the repair and the intact states (n.s.). No significant differences were found in the average contact pressure between the repair, intact, or maximum extrusion conditions at any flexion angle (n.s.). No significant differences were found in the peak contact pressure between the repair, intact, or maximum extrusion conditions at any flexion angle (n.s.). CONCLUSION: In this in vitro model, medial meniscus extrusion greater than 4 mm reduced medial compartment contact area, but meniscal extrusion did not significantly increase pressure in the medial compartment. Additionally, meniscal centralization was effective in restoring the medial tibiofemoral contact area to intact state when the meniscal extrusion was secondary to meniscotibial ligament injury. The diagnosis of meniscal extrusion may not necessarily involve meniscal root injury. Since it is known that meniscal extrusion greater than 3 or 4 mm has a biomechanical impact on tibiofemoral compartment contact area and pressures, specific treatments can be established. Centralization restored medial compartment contact area to the intact state.

Anterior Cruciate Ligament Tears: The Impact of Increased Time From Injury to Surgery on Intra-articular Lesions.

BACKGROUND: Previous research has shown that meniscal and articular cartilage lesions increase with time in the anterior cruciate ligament (ACL)-deficient knee. PURPOSE: To analyze the association between increased time from ACL injury to reconstruction and the presence of intra-articular lesions. DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A retrospective chart review was performed for patients who sustained an ACL injury and underwent reconstruction from January 1, 2009, to May 14, 2015. Factors analyzed included age, sex, and body mass index, as well as time from injury to surgery, the presence of meniscal tears, and the presence of cartilage lesions. The data were evaluated to quantify the association between time from ACL injury to reconstruction and presence of intra-articular lesions. RESULTS: Overall, 405 patients were included in this study. Regarding time from injury, 27.3% patients were treated at <3 months, 23.6% at 3 to <6 months, 18% at 6 to <12 months, 13.6% at 12 to <24 months, 10.6% at 24 to <60 months, and 6.9% at ≥60 months. When compared with the group treated <3 months from injury, a significant increase in the rate of medial meniscal tears was seen in the groups treated at 6 to <12 months (odds ratio [OR], 2.2), 12 to <24 months (OR, 3.5), 24 to <60 months (OR, 7.0), and ≥60 months (OR, 6.3). A similar trend was seen with medial femoral condyle lesions in the groups treated at 6 to <12 months (OR, 2.5), 12 to <24 months (OR, 2.6), 24 to <60 months (OR, 2.6), and ≥60 months (OR, 6.9). The prevalence of lateral tibial plateau and lateral femoral condyle lesions also significantly increased with increased time between ACL injury and reconstruction, but this association was not seen until 24 to <60 months (ORs, 5.1 and 11.5, respectively). CONCLUSION: For patients undergoing ACL reconstruction, an interval >6 months between injury and surgery was associated with an increased prevalence of medial meniscal tears and medial compartment chondral lesions at the time of surgery. An interval >24 months between injury and surgery was associated with an increased prevalence of lateral compartment chondral lesions at the time of surgery.

Shoulder Instability: Anterior, Posterior, Multidirectional, Arthroscopic Versus Open, Bone Block Procedures.

This article presents a retrospective comprehensive review of the history of anterior, posterior, and multidirectional shoulder instability and also reviews key concepts such as open versus arthroscopic repair and glenoid and humeral head bone loss and associated treatments. The future of shoulder instability will continue to evolve as research and clinical experience will determine the direction of the future.