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 proinflammatory macrophages or M2 anti-inflammatory macrophages was measured using gene expression, protein expression, flow cytometry, and nitric oxide production. RESULTS: Tendon and bursa treated with PRP, AAS, and PRP+AAS significantly decreased the gene expression of M1 markers interleukin (IL)-12 and tumor necrosis factor-alpha while significantly increasing the expression of M2 markers arginase, IL-10, and transforming growth factor-ß (P < .05) compared with treatment with control. Enzyme-linked immunosorbent assay analysis of protein production demonstrated that, compared with control, coculture treated with PRP, AAS, and PRP+AAS significantly decreased markers of M1-macrophages (IL-6, IL-12, and tumor necrosis factor-alpha) while significantly increasing the expression of markers of M2-macrophages (arginase, IL-10, and transforming growth factor-beta) (P < .05). Flow cytometry analysis of surface markers demonstrated that compared with 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 < .05). Treatment of the coculture with PRP, AAS, and PRP+AAS consistently demonstrated a decrease in nitric oxide production (P < .05) compared with control. AAS and PRP+AAS demonstrated an increased macrophage shift to M2 compared with PRP alone, whereas there was not as uniform of a shift when comparing PRP+AAS with 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 proinflammatory M1-macrophages. AAS and PRP+AAS contributed to a large shift to macrophage polarization to the anti-inflammatory M2 compared with PRP. CLINICAL RELEVANCE: The mechanism of biologic adjuvant effects on the rotator cuff remains poorly understood. This study suggests that they may contribute to polarization of macrophages for their proinflammatory (M1) state to the anti-inflammatory (M2) state.

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.

Favorable Patient-Reported Outcomes and High Return to Sport Rates Following Hip Arthroscopy in Adolescent Athletes: A Systematic Review.

PURPOSE: The purpose of this systematic review is to synthesize the existing literature surrounding hip arthroscopy in the adolescent athlete population to determine patient-reported outcomes, return to sport rates, complications, and reoperations associated with this intervention. METHODS: A systematic literature review was performed using PubMed (MEDLINE), Cochrane Library, and Embase according to PRISMA guidelines. Studies were included if they were published in English with greater than 2 participants, contained patients aged 10-19 years old or classified as "high school athletes" or "middle school athletes," and reported postoperative patient-reported outcomes and return to sport. Patient-reported outcomes (PROs) and their associated P values were recorded. Finally, return-to-sport outcomes and sports played were also extracted from the included studies. Weighted kappa was used to assess inter-reviewer agreement. RESULTS: Eleven studies included in the final analysis, resulting in 344 patients and 408 hips were analyzed by this review. Patient-reported outcomes (PROs) were reported in all studies. The modified Harris Hip Score (mHHS) was used in all but 1 study. Six of the 11 studies reported a 100% return-to-sport rate, for a total of 98/98 athletes returning to sport. Fabricant et al. did note that a majority of athletes who returned to sport were able to do so at a subjective "nearly normal" level. Only 4 of the studies reported complications, with the majority being transient neuropraxias. CONCLUSIONS: Adolescent athletes who undergo hip arthroscopy demonstrate favorable postoperative patient-reported outcome scores, high rates of return to sport, and an overall low complication rate. The heterogeneity in both surgical methodology and outcome measures used for evaluation and treatment leads to continued ambiguity with regard to the optimal method for managing adolescent athletes with hip pathology. LEVEL OF EVIDENCE: V, systematic review of Level II-V studies.

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.

Inspiring Women in Engineering and Medicine: The Impact of a One-Day STEM Experience on High School Females' Attitude Toward Male-Dominant Professions.

OBJECTIVE: Inspiring Women in Orthopedics and Engineering (IWEM) is a program founded by UConn Health orthopedic surgeon Dr. Katherine Coyner (KC) focused on boosting diversity and introducing young women to the traditionally male-dominant fields of orthopedics and engineering. Over the course of one day, we assessed change in interest in (1) STEM, (2) medical school, (3) orthopedic surgery, and (4) confidence in performing basic surgical skills. DESIGN: Pre- and postevent matched surveys. SETTING: UConn Health, Department of Orthopedic Surgery. PARTICIPANTS: Ten IWEM events were held from 2018 to 2020. Data was collected on a total of 475 female high school student applicants from across Connecticut were accepted into one of the IWEM workshops based on their responses to short answer questions. RESULTS: In response to the statement "I am interested in orthopedics" 127 students (27%, p < 0.01) changed their answer after participating in the IWEM workshop and a significant number of participants reported feeling more confident and competent in the use of power tools as well as a self-reported increased understanding of basic orthopedic surgery knowledge. Additionally, participants scored significantly higher on a 6-question quiz evaluating orthopedic knowledge after attending the workshop. CONCLUSIONS: An immersive 1-day program that provides exposure to orthopedic surgery and STEM careers creates increased interest in these fields and may combat the large gender disparity that persists in these fields today.

Confirming Proper Button Deployment of Suspensory Fixation During ACL Reconstruction.

BACKGROUND: Suspensory fixation of anterior cruciate ligament (ACL) reconstruction (ACLR) grafts has emerged as a popular device for femoral graft fixation. However, improper deployment of the suspensory fixation can compromise proper graft tensioning, leading to failure and revision. Also, soft tissue interposition between the button and bone has been associated with graft migration and pain, occasionally requiring revision surgery. Many surgeons rely on manual testing and application of distal tension to the graft to confirm proper button deployment on the lateral cortex of the femur for ACL graft fixation. PURPOSE: To determine the reliability of the manual resistance maneuver when applying distal tension to deploy the suspensory device along the lateral cortex of the femur. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: All patients undergoing ACLR with a suture button suspensory device for femoral fixation were eligible for enrollment in the study. The surgeries were performed by 3 board-certified, sports medicine fellowship-trained orthopaedic surgeons at a single outpatient surgical center between May 2018 and June 2019. All grafts were passed in a retrograde manner into the femoral tunnel, and a vigorous manual tensioning maneuver in a distal direction was placed on the graft to deploy and secure along the lateral cortex of the femur. Intraoperative mini c-arm fluoroscopy was obtained to demonstrate proper suture button positioning. If interposing tissue or an improperly flipped button was identified, rectifying steps were undertaken and recorded. RESULTS: A total of 51 patients with a mean age of 33.3 years were included in the study. Of these patients, 74.5% had normal suture button positioning identified via intraoperative fluoroscopic imaging, while 15.7% had interposed soft tissue and 9.8% had an improperly flipped button. In all cases, the surgeon was able to rectify the malpositioning intraoperatively. CONCLUSION: Despite the manual sensation of proper suspensory button positioning, intraoperative fluoroscopy identified suture button deployment errors in ACLR 25% of the time. Correcting the malpositioning is not technically demanding. These findings advocate for routine intraoperative surveillance to confirm appropriate suture button seating during ACLR.

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.

Biomechanical Comparison of Anterograde and Retrograde Lesser Trochanter Avulsion Repair.

BACKGROUND: Lesser trochanter avulsions are rare injuries in adolescents. Severe cases with relevant fragment displacement can be treated surgically. However, no standard approach is available in the literature. Operative techniques are presently limited to anterograde fixations. A new retrograde approach to reduce operative difficulty and postoperative morbidity has been proposed. So far, no biomechanical comparison of these techniques is available. HYPOTHESIS: Retrograde repair of the lesser trochanter with a titanium cortical button will produce superior stability under load to failure and similar displacement under cyclic loading compared with anterograde fixation with titanium suture anchors. STUDY DESIGN: Controlled laboratory study. METHODS: Sixteen paired hemipelvic cadaveric specimens (mean age, 62.5 ± 10.7 years) were dissected to isolate the lesser trochanter and iliopsoas muscle. After repair of a simulated lesser trochanter avulsion, specimens were tested under cyclic loading between 10 and 125 N at 1 Hz for 1500 cycles before finally being loaded to failure at a rate of 120 mm/min in a material testing machine. Motion tracking was used to assess displacement at the superior and inferior aspects of the iliopsoas tendon under cyclic loading. RESULTS: Load to failure was significantly greater for the retrograde repair compared with the anterograde repair (1075.24 ± 179.39 vs 321.85 ± 62.45 N; P = .012). Mean displacement at the superior repair aspect (retrograde vs anterograde: 3.29 ± 1.84 vs 4.39 ± 4.50 mm; P = .779) and mean displacement at the inferior aspect (3.54 ± 2.13 vs 4.22 ± 4.48 mm; P = .779) of the iliopsoas tendon did not significantly differ by the type of repair. Mode of failure was tendon tearing by the sutures for each retrograde repair and anchor pullout for each anterograde repair. CONCLUSION: Surgical repair of lesser trochanter avulsion fractures with retrograde fixation using a titanium cortical button demonstrated superior load to failure and similar displacement under cyclic loading compared with anterograde fixation using suture anchors. CLINICAL RELEVANCE: The retrograde approach provides a biomechanically validated alternative to other surgical techniques for this injury.

Biomechanical Evaluation of Proximal Hamstring Repair: All-Suture Anchor Versus Titanium Suture Anchor.

BACKGROUND: Proximal hamstring avulsions are severe tendon injuries and are commonly sports-related. Open and endoscopic techniques as well as different anchor configurations have already been described for proximal hamstring repair. Novel all-suture anchors have been developed to provide decreased bone loss during placement and reduced occupied bone volume when compared with titanium suture anchors. HYPOTHESIS: Complete proximal hamstring avulsions repaired with all-suture anchors will demonstrate equal load to failure and comparable displacement under cyclic loading when compared with titanium suture anchors. STUDY DESIGN: Controlled laboratory study. METHODS: Complete proximal hamstring avulsions were created in 18 paired cadaveric specimens (mean ± SD age, 63.0 ± 10.4 years). Either all-suture anchors or titanium suture anchors were used for repair. Cyclic loading from 10 to 125 N at 1 Hz was performed for 1500 cycles with a material testing machine. Displacement was assessed along anterior and posterior aspects of the tendon repair with optical tracking. Specimens were loaded to failure at a rate of 120 mm/min. Displacement, load to failure, and repair construct stiffness were compared between matched pairs with the Wilcoxon signed-rank test. Correlations were determined by Spearman rho analysis. RESULTS: The all-suture anchors showed significantly higher load-to-failure values when compared with the titanium anchor repairs (799.64 ± 257.1 vs 573.27 ± 89.9 N; P = .008). There was no significant difference in displacement between all-suture anchors and titanium suture anchors at the anterior aspect (6.60 ± 2.2 vs 5.49 ± 1.1 mm; P = .26) or posterior aspect (5.87 ± 2.08 vs 5.23 ± 1.37 mm; P = .678) of the repaired hamstring tendons. CONCLUSION: All-suture anchors demonstrated similar displacement and superior load to failure when compared with titanium suture anchors. CLINICAL RELEVANCE: The results of this study suggest that all-suture anchors are an equivalent alternative to titanium suture anchors for proximal hamstring avulsion repair.

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.

Bone and joint modeling from 3D knee MRI: feasibility and comparison with radiographs and 2D MRI.

PURPOSE: The purpose was to evaluate feasibility of bone and joint segmentations from three-dimensional magnetic resonance imaging (3D MRI). METHODS: Segmented joint models from 3D MRI data set were obtained for 42 patients. Blinded angular and joint space measurements were performed on 3D MRI model, two-dimensional (2D) MRI, and radiography (XR). RESULTS: Medial joint space was similar on both XR and 3D MRI (P=.3). The XR measurements were statistically different but closer to 3D MRI for lateral patellar tilt angle, patellar tendon length, and lateral knee joint space, whereas 2D MRI measurements were closer to XR in terms of trochlear depth, sulcal angle, and patellar length. CONCLUSION: 3D bone and joint segmentations are feasible from isotropic MRI data sets.

ISAKOS classification of meniscal tears-illustration on 2D and 3D isotropic spin echo MR imaging.

Magnetic Resonance Imaging is modality of choice for the non-invasive evaluation of meniscal tears. Accurate and uniform documentation of meniscal pathology is necessary for optimal multi-disciplinary communication, to guide treatment options and for validation of patient outcomes studies. The increasingly used ISAKOS arthroscopic meniscus tear classification system has been shown to provide sufficient interobserver reliability among the surgeons. However, the terminology is not in common use in the radiology world. In this article, the authors discuss the MR imaging appearances of meniscal tears based on ISAKOS classification on 2D and multiplanar 3D isotropic spin echo imaging techniques and illustrate the correlations of various meniscal pathologies with relevant arthroscopic images.

T2 black lesions on routine knee MRI: differential considerations.

The majority of abnormal findings or lesions on T2-weighted fast spin-echo (FSE) magnetic resonance imaging (MRI) are hyperintense due to increased perfusion or fluid content, such as infections, tumours or synovitis. Hypointense lesions on T2-weighted images (both fat-suppressed and non-fat-suppressed) are less common and can sometimes be overlooked. Such lesions have limited differential diagnostic possibilities, and include vacuum phenomenon, loose body, tenosynovial giant cell tumour, rheumatoid arthritis, haemochromatosis, gout, amyloid, chondrocalcinosis, hydroxyapetite deposition disease, lipoma arborescens, arthrofibrosis and iatrogenic lesions. These lesions often show characteristic appearances and predilections in the knee. In this article, the authors describe the MRI features of hypointense T2 lesions on routine knee MRI and outline a systematic diagnostic approach towards their evaluation. Key Points • Hypointense lesions on T2 images (T2 Dark Lesions) encompass limited diagnostic possibilities. • T2 Dark lesions often show characteristic appearances and predilections in the knee. • A systematic diagnostic approach will help radiologists make the correct diagnosis.

The reliability and diagnostic accuracy of assessing the translation endpoint during the lachman test.

BACKGROUND: Interpretation of Lachman testing when evaluating the status of the anterior cruciate ligament (ACL) typically includes a numerical expression classifying the amount of translation (Grade I, II, III) in addition to a categorical modifier (Grade A [firm] or B [absent]) to describe the quality of the passive anterior tibial translation's endpoint. Most clinicians rely heavily on this tactile sensation and place value in this judgment in order to render their diagnostic decision; however, the reliability and accuracy of this endpoint assessment has not been well established in the literature. PURPOSE: The purpose of this study was to determine the intertester reliability of endpoint classification during the passive anterior tibial translation of a standard Lachman test and evaluate the classification's ability to accurately predict the presence or absence of an ACL tear. STUDY DESIGN: Prospective, blinded, diagnostic reliability and accuracy study. METHODS: Forty-five consecutive patients with a complaint of knee pain were independently evaluated for the endpoint classification during a Lachman test by two physical therapists before any other diagnostic assessment. The 21 men and 24 women ranged in age from 20 to 64 years (mean +/- SD age, 40.7 +/- 14) and in acuity of knee injury from 30 to 365 days (mean +/- SD, 238 +/-157). RESULTS: 17 of the 45 patients had a torn ACL. The agreement between examiners on A versus B endpoint classification was 91% with a kappa coefficient of 0.72. In contrast, classification agreement based on the translational amount had an agreement of 65% with a weighted kappa coefficient of 0.52. The sensitivity of the endpoint grade alone was 0.81 with perfect specificity resulting in a positive likelihood ratio of 6.2 and a negative likelihood ratio of 0.19. The overall accuracy of the Lachman test using the endpoint assessment grade alone was 93% with a number needed to diagnose of 1.2. CONCLUSIONS: Nominal endpoint classification (A or B) from a Lachman test is a reliable and accurate reflection of the status of the ACL. The true dichotomous nature of the test's interpretation (positive vs. negative) is well-served by the quality of the endpoint during passive anterior tibial translation. LEVEL OF EVIDENCE: 2.