Tear Length Research Articles

Prospective Short-term MRI controlled investigation of the healing properties of the Meniscus

Aims and Objectives:The purpose of the study was to prospectively investigate signal alterations in short-term follow-up after acute meniscus repair on specific magnetic resonance imaging (MRI) scan sequences. It was hypothesized that 1) there are different meniscus healing properties depending on lesion configuration and size, and 2) the tear zone has an influence on the healing properties of the meniscus.Materials and Methods:We conducted this prospective short-term clinical and radiological study to investigate the healing properties of acute meniscus tears. Inclusion criteria were patients (age 18-45 years) with traumatic meniscus lesion, subsequent arthroscopic meniscus repair within 6 weeks and preoperative MRI. Exclusion criteria were age < 18 or >45 years, arthrosis > grade III and multiligamentous knee injuries. Clinical examination and outcome scores (IKDC, KOOS, Lysholm Score) were surveyed preoperatively and 12 weeks after surgery. Meniscus tears were classified according to the ISAKOS meniscus classification system on MRI scans. Radiological assessment using a 3T-MRI was performed preoperatively and 2, 4, 6 and 12 weeks after operation. Meniscus healing were classified according to Henning’s criteria in A) healed, B) partially healed (> 50%) and C) not healed. Data were analyzed using SPSS statistics software version 21 (IBM, New York, USA). Statistical significance was set at a p value of < 0.05.Results:These are preliminary results of 14 patients (13 m, 1w) with a total of 16 meniscus tears. According to the ISAKOS meniscus classification system 9 medial and 7 lateral meniscus tears were included and average tear length was 21.5 mm (6 - 40 mm). 12 tears were located in the rim zone 1 and 4 tears were more medially in zone 2. In 8 (57%) patients an additional anterior cruciate ligament (ACL) reconstruction was performed. Six weeks postoperatively 8 menisci (50%) were deemed healed, 6 menisci (37%) partially healed whereas 2 menisci were not healed (13%). After 12 weeks 9 menisci (56%) were considered healed, 4 menisci (25%) partially healed and 3 menisci (19%) showed intrameniscal joint fluid in more than 50% of meniscus thickness. Two bucket handle tears of the medial meniscus and one radial tear of the lateral meniscus, all located in the red-red zone sized 35 mm, 25 mm and 12 mm, were not healed after 12 weeks. Clinical scores improved significantly 12 weeks after surgery: IKDC Score (preOP: 46.7, postOP: 67.8), KOOS (preOP: 49.7, postOP: 79.1) and Lysholm Score (preOP: 49.5, postOP: 77.7) (p < 0.05).Conclusion:Clinical and radiological follow-up showed good short-term results after meniscus repair. MRI revealed signal alteration in all menisci after 12 weeks, in most instances considered as scar tissue without intrameniscal joint fluid. In this cohohrt tear size and location was not correlated with non-healing. Arthroscopic meniscus repair achieves a high healing response of the meniscus and good clinical outcomes.

Does the Critical Shoulder Angle Correlate With Rotator Cuff Tear Progression?

The critical shoulder angle (CSA) has been reported to be associated with rotator cuff disease and has been suggested as an etiology for cuff tears. However, it is unclear whether acromial morphologic characteristics such as CSA are a cause or effect because all studies to date have been retrospective. (1) How often can the CSA be reliably measured? (2) Is the CSA associated with rotator cuff disease? (3) Is the CSA correlated with baseline tear size or tear enlargement? (4) Does the CSA change with time? In this retrospective comparison of longitudinally collected data, patients with asymptomatic rotator cuff tears underwent ultrasonography and standardized AP radiographs at enrollment and yearly thereafter during a median of 4 years. Three hundred ninety-five patients were included, of whom 14 were excluded as they were not yet eligible for 2-year followup and 68 (18%) were lost to followup, leaving 313 study patients who were evaluated with 1433 radiographs. Patients with adhesive capsulitis with normal rotator cuffs and radiographically normal scapulae were included as control subjects (119 subjects). Two observers (PNC, DS) measured the CSA in a blinded fashion. Radiographs that met Suter-Henninger criteria for CSA measurement reliability were included. For the study group, 179 of the 313 (57%) patients with radiographs that met Suter-Henninger criteria were further analyzed; the remainder were excluded from this study. For the control group, 50 of 119 (42%) subjects met criteria and were further analyzed. Tear enlargement was found in 94 patients, and the CSA was compared in patients with tears and control subjects, and in tears with or without enlargement, and was correlated with tear size. In a subgroup of the study group in which 59 of 179 patients had a minimum of 3 years between initial and followup radiographs, two CSA measurements were performed to measure change. In total, of the 1552 radiographs evaluated, only 326 (21%) were of sufficient quality to measure the CSA. The CSA was higher among patients with cuff tears than control subjects (34° ± 4° versus 32° ± 4°; mean difference, 2.0°; 95% CI, 0.7°-3.2°; p = 0.003). The CSA did not correlate with baseline tear length (ρ = 0.22, p = 0.090) or width (ρ = 0.16, p = 0.229). The CSA was not different between tears that enlarged and those that were stable (34° ± 3° versus 34° ± 4°; mean difference, 0.2°; 95% CI, -0.9° to -1.4°; p = 0.683). The CSA did not change over time (CSA Time 1: mean 33° ± 4° SD; CSA Time 2: mean 33° ± 4° SD; mean difference, -0.2°; 95% CI, -0.6° to 0.1°; p = 0.253). Even with a longitudinal protocol, most radiographs are of insufficient quality for CSA measurement. Although patients with a history of degenerative cuff disease have higher CSA values than control subjects, the difference is small enough that it could be influenced by measurement error in practice; in any case, a difference of the magnitude we observed is likely to be clinically unimportant. The CSA is not correlated with tear size or tear progression, and does not seem to change with time. These results suggest that the CSA is unlikely to be related to rotator cuff disease. Level II, prognostic study.

Clinical analysis of eight patients with blunt main stem bronchial injuries.

Blunt main stem bronchial injuries are rare but potentially life-threatening injuries in clinical. The aim of this study was to sum up the experience on diagnosis and treatment of blunt main stem bronchial injuries. This report retrospective1y analyzed eight cases of main stem bronchial injuries induced by blunt chest trauma between 2013 and 2016 in Tangdu Hospital, Fourth Military Medical University. There were eight patients, including four men and four women. The definitive diagnosis was confirmed by fibrobronchoscopy. Mean time between injury and treatment in our hospital was 4.25 days (range, 1-12 days). Mean length of airway tear was 1.04 cm (range, 0.5-2 cm). In four patients there was an injury to the left main stem bronchus, in three patients to the right main stem bronchus and in one patient to the ambilateral main stem bronchus. Emergent operation was performed in two patients and elective operation in six patients. End to end bronchial anastomosis was performed via right thoracotomy in two patients and via left thoracotomy in three patients, and primary repair was performed via right thoracotomy in two patients and via left thoracotomy in the remaining one patient. There was no death in this group. Seven patients had no complications and were able to take part in normal activities. One patient suffered from anastomotic stricture after operation was healed by granulation tissue resection and cryotherapy under fibrobronchoscopy. Fibrobronchoscopy is able to define the blunt main stem bronchial injuries precisely and surgical approach is the preferred method for patients with these life-threatening complications.

Propagation of dissection in a residually-stressed artery model

This paper studies dissection propagation subject to internal pressure in a residually-stressed two-layer arterial model. The artery is assumed to be infinitely long, and the resultant plane strain problem is solved using the extended finite element method. The arterial layers are modelled using the anisotropic hyperelastic Holzapfel–Gasser–Ogden model, and the tissue damage due to tear propagation is described using a linear cohesive traction–separation law. Residual stress in the arterial wall is determined by an opening angle alpha in a stress-free configuration. An initial tear is introduced within the artery which is subject to internal pressure. Quasi-static solutions are computed to determine the critical value of the pressure, at which the dissection starts to propagate. Our model shows that the dissection tends to propagate radially outwards. Interestingly, the critical pressure is higher for both very short and very long tears. The simulations also reveal that the inner wall buckles for longer tears, which is supported by clinical CT scans. In all simulated cases, the critical pressure is found to increase with the opening angle. In other words, residual stress acts to protect the artery against tear propagation. The effect of residual stress is more prominent when a tear is of intermediate length (simeq 90^circ arc length). There is an intricate balance between tear length, wall buckling, fibre orientation, and residual stress that determines the tear propagation.

Intraobserver and Interobserver Agreement of Magnetic Resonance Imaging for Reparability of Peripheral Meniscal Tears: What Criteria Really Matter?

The objective of the study was the determination of the intra- and interobserver agreement of three magnetic resonance imaging (MRI) criteria for reparability: a peripheral rim smaller than 4 mm, a tear longer than 10 mm, and homogenous aspect of meniscal tissue. In two rounds with an interval of at least 6 weeks, three orthopedic surgeons and three musculoskeletal radiologists studied the preoperative MRI scans of 63 patients with a longitudinal full-thickness medial or lateral meniscal tear. All patients had an arthroscopic meniscal repair. The blinded images were evaluated measuring the tear length and rim width and meniscal aspect was classified. Agreement was calculated using the linear-weighted kappa coefficient (κ) and the intraclass correlation coefficient (ICC). Examiner agreement strength was defined according to the guidelines of Landis and Koch. Intraobserver agreement was poor to good (κ, 0.12-0.72) for the classification of the meniscal aspect and decreased in lateral meniscal tears. The interobserver agreement for meniscal aspect was mainly poor to fair (κ, 0.09-0.53). The intraobserver reliability for measurement of the length of the meniscal tear was moderate to excellent (ICC, 0.51-0.80) for all observers in both rounds and moderate to good (ICC, 0.59-0.73) for measurement of the peripheral rim width. The interobserver agreement on tear length and rim width was moderate in both rounds (ICC, 0.58 and 0.50 in round 1; 0.50 and 0.50 in round 2, respectively). Tear length and rim width are the only two measurements with moderate to good agreement. However, these measurements do not predict reparability of longitudinal meniscal tears on MRI images.

Factors Affecting Clinical Outcome in Patients With Structural Failure After Arthroscopic Rotator Cuff Repair

(1) To compare clinical outcomes between patients with large or massive rotator cuff tears who have healed cuffs and patients with postoperative structural failure (retear after complete or partial repair) and (2) to identify factors associated with clinical outcomes in patients with postoperative structural failure. We conducted a retrospective study of consecutive patients with large or massive cuff tears who underwent arthroscopic repair at our institution between 2005 and 2012. On the basis of intraoperative findings and magnetic resonance imaging at final follow-up, the patients were divided into 3 groups: healed group, retear group (after complete repair), and partial-repair group. The outcome measures comprised the Japanese Orthopaedic Association (JOA) and University of California, Los Angeles (UCLA) scores; muscle strength; and range of motion. The tear length, tear width, muscle atrophy, and fatty degeneration were evaluated by preoperative and postoperative magnetic resonance imaging. The extent of tendon reattachment to the superior, middle, and inferior facets and the lesser tuberosity was examined on magnetic resonance images at final follow-up. In total, 74 patients (healed, 41; retear, 19; and partial repair, 14) were included in this study. The mean age was 63.8 ± 8.5 years, with a mean follow-up period of 3.6 ± 1.4 years. The postoperative JOA and UCLA scores significantly improved in all 3 groups, but the differences were not significant. In the retear and partial-repair groups, postoperative tendon preservation at the middle facet significantly affected the JOA and UCLA scores (P= .003 and P=.014, respectively). The JOA and UCLA scores were significantly improved in patients with structural failure. Under these conditions, the only clinical factor that affected patient outcome was tendon healing at the middlefacet. Thus tendon preservation at the middle facet was a predictor of good clinical outcomes in patients who underwent arthroscopic rotator cuff repair of large or massive tears and had postoperative structural failure. Level III, case-control study.

Iatrogenic injuries to the trachea and main bronchi.

IntroductionIatrogenic tracheobronchial injuries are rare.AimTo analyse the mechanism of injury, symptoms and treatment of these patients.Material and methodsRetrospective analysis of hospital records of all patients treated for main airway injuries between 1990 and 2012 was performed.ResultsThere were 24 patients, including 21 women and 3 men. Mean time between injury and initiation of treatment was 12 hours (range: 2-48). In 16 patients the injury occurred during tracheal intubation, in 1 during rigid bronchoscopy, in 1 during rigid oesophagoscopy, in 1 during mediastinoscopy and in 5 during open surgery. Mean length of airway tear was 3.8 cm (range: 1.5-8). In 1 patient there was an injury to the cervical trachea and in the remaining 23 in the thoracic part of the airway. The treatment included repair of the membranous part of the trachea performed via right thoracotomy in 10 patients (in 1 patient additionally coverage with a pedicled intercostal muscle flap was used), a self-expanding metallic stent in 1 patient, suture of the right main bronchus and the oesophagus in 1, left upper sleeve lobectomy in 1, right upper lobectomy in 1, implantation of a silicone Y stent in 3, mini-tracheostomy in 1, and conservative treatment in 5 patients.ConclusionsIntubation is the most frequent cause of iatrogenic main airway injuries. Patients with these life-threatening complications require an individualised approach and treatment in a reference centre.

18 Propagation of arterial dissection

We compute and study critical pressures (Pc) for the initiation of the propagation of an existing arterial dissection, which in general depends on the residual stress and pre-stretch of the artery, and the length and depth of the tear, using the Holzapfel-Gasser-Ogden mathematical model for the walls of the large arteries. For the simple case of a 2D tissue sample, increasing the length of the initial dissection lowers the value of Pc, but when the strip is supported by connective tissue, arrest of the dissection is obtained. A peeling test on a disc-shaped sample demonstrates that the orientation of collagen fibres plays an important role in the direction of propagation. To study the effects of residual stress on arterial dissection, we include residual stress, quantified by the opening angle when an artery is subject to a longitudinal cut. We show that Pc is approximately proportional to the opening angle, so that the observed loss of residual stress associated with ageing increases the likelihood of dissection. Finally the effects of the circumferential (arc) length and radial position of the initial tear in a cylindrical model of an artery are investigated. Pc decreases as arc length increases and as the initial dissection is placed closer to the lumen. Prolapse of the dissection into the lumen occurs when the initial tear close to the lumen and the arc length is large.

Effect of Solidified Structure on Hot Tearing in Al-Cu Alloy

Hot tearing is the one of the biggest problems when casting aluminium alloys. Although there has been much research work in this field, it is still not clear what causes hot tearing and how it propagates. Furthermore, the effect of solidified structure on the hot tearing has not been clear. Therefore, this study has been carried out to correlate the solidified structure and hot tearing. Al-2.0 wt% Cu alloy was used for test alloy. To change the solidified structure, some amount of refiner was added to the molten alloy. A permanent mould, which has been developed by us, can form hot tearing intentionally in the center region of a solidified shell. The cross section of a solidified shell was metallographically investigated and solidified structure and hot tearing were characterized. The length of hot tear decreased with increasing the amount of refiner. This may indicate that it is difficult for hot tear with fine equiaxed grains to propagate. In addition to this, the residual liquid around the hot tear was moved to the cracking due to negative pressure and hot tearing was partially healed.

Clinical Outcomes and Structural Healing After Arthroscopic Rotator Cuff Repair Reinforced With A Novel Absorbable Biologic Scaffold: A Prospective, Multicenter Trial

Objectives:Arthroscopic rotator cuff repair has been demonstrated to provide reliable clinical outcomes, but the rate of retear remains high (11% to 94%). Retears are associated with poorer outcomes and the majority of retears have been shown to occur within 6 months after surgical repair. Improving the mechanical and/or biological environment during index repair is a common strategy utilized to reduce retear rate. Biofiber© is a bi-layer, absorbable reinforced poly (4)-hydroxybutyrate scaffold that can be used to reinforce rotator cuff repair. Rotator cuff repairs augmented with Biofiber appear to have improved biomechanical properties as compared to standard repair constructs in cadaveric study. Therefore, BioFiber augmented rotator cuff repair may be a viable consideration for patients with larger tears, poorer tissue quality, or in revision repairs. The purpose of this prospective multi-center clinical trial is to evaluate the clinical outcomes and rates of successful healing by ultrasound evaluation in patients undergoing augmented arthroscopic rotator cuff repair using a BioFiber scaffold.Methods:A cohort of 50 patients were prospectively enrolled from three study sites in the US (2 sites) and France (1 site). Patients with an imaging demonstrated and arthroscopically confirmed full-thickness rotator cuff tear who underwent arthroscopic rotator cuff repair augmented with a BioFiber scaffold were included in the study. All patients were evaluated clinically at baseline prior to surgery, and subsequently at 6 months and 1 year post-operatively using functional outcomes evaluation (Constant Score and WORC Index), ROM, and strength testing. Ultrasound evaluation at 6 months and 1 year was also carried out to assess repair integrity.Results:The average patient age of the cohort was 61 ± 9 years with an average BMI of 28.4. There were 27 female (54%) and 23 male (46%) patients; 10% of those enrolled were worker's compensation patients, 12% were undergoing revision rotator cuff repair. The average AP tear length was 25.2mm ± 1.8mm with an average retraction of 17.1mm ± 1.2mm from the greater tuberosity. Arthroscopic repairs were achieved in all 50 patients using either double-row (78%) or single-row (22%) constructs. The total surgical time for the procedure averaged 77 minutes, with a mean time required for placement of the Biofiber scaffold of 17 minutes. At 6 months post-operatively, the mean adjusted Constant Score was 94.0 (baseline 61.0) and the mean WORC Index was 82.1 (baseline 37.5). Ultrasound evaluation demonstrated intact repairs in 96% of the evaluated patients at the 6 month time point, with no additional evidence of repair failure at 1 year.Conclusion:This interim analysis suggests that reinforcement of rotator cuff repairs with Biofiber may result in a mechanically superior repair leading to a high rate of tendon healing. Tear size and quality of repair have been the best predictors for tendon healing in rotator cuff surgery, with recent studies demonstrating improved Constant scores when tendon healing is seen on ultrasound. This cohort had 96% rate of repair integrity on ultrasound evaluation. Furthermore, functional outcome scores after Biofiber-augmented repair were equal to or better than those recently reported for similar populations. Given this data, arthroscopic rotator cuff repair using a BioFiber augmented repair may provide a promising option in the treatment of patients with full-thickness rotator cuff tears.

Ultrasound determination of rotator cuff tear repairability.

Rotator cuff repair aims to reattach the torn tendon to the greater tuberosity footprint with suture anchors. The present study aimed to assess the diagnostic accuracy of ultrasound in predicting rotator cuff tear repairability and to assess which sonographic and pre-operative features are strongest in predicting repairability. The study was a retrospective analysis of measurements made prospectively in a cohort of 373 patients who had ultrasounds of their shoulder and underwent rotator cuff repair. Measurements of rotator cuff tear size and muscle atrophy were made pre-operatively by ultrasound to enable prediction of rotator cuff repairability. Tears were classified following ultrasound as repairable or irreparable, and were correlated with intra-operative repairability. Ultrasound assessment of rotator cuff tear repairability has a sensitivity of 86% (p < 0.0001) and a specificity of 67% (p < 0.0001). The strongest predictors of rotator cuff repairability were tear size (p < 0.001) and age (p = 0.004). Sonographic assessments of tear size ≥4 cm(2) or anteroposterior tear length ≥25 mm indicated an irreparable rotator cuff tear. Ultrasound assessment is accurate in predicting rotator cuff tear repairability. Tear size or anteroposterior tear length and age were the best predictors of repairability.

Effect of solidified structure on hot tear in Al-Cu alloy

Hot tear is the one of the biggest problems of cast products of aluminum alloy. The effect of solidified structure on the hot tear has not been clear. Therefore, this study has been carried out to correlate solidified structure and hot tear. Al-2.0 wt% Cu alloy was cast at 750 °C in a moldcavity, which could intentionally form hot tear. To change solidified structure, some amount of refiner was added to the molten alloy. Length of hot tear decreased with increasing the amount of refiner. Further, the area of fine eutectic Al2Cu increased as amount of refiner increased. These may indicate that probability of healing increased in case of equiaxed structure. Therefore, the length of hot tear decreased with increasing the amount of refiner. great care should be taken in constructing both.

Evaluation of the results of arthroscopic meniscal repair

Introduction Menisci have a role in optimal knee function. Meniscal preservation in younger active individuals presenting with symptomatic meniscal disease is important. The success of meniscal repair depends on appropriate meniscal bed preparation and the surgical technique. Patients and methods A prospective study of 20 cases of post-traumatic meniscal tear was conducted during the period between March 2012 and December 2013. All cases were subjected to arthroscopic evaluation to confirm the diagnosis and ensure they fulfilled the criteria for repair on the basis of site, size, description, and associated injury of the tear. The inclusion criteria were vertical longitudinal tear from 1 to 3 cm in length in the red-red or red-white zone. The exclusion criteria were patient age older than 45 years, white-white zone tear, radial tear, and complex degenerative meniscal tear. The Lysholm score and International Knee Documentation Committee (IKDC) subjective and objective knee scores were used preoperatively and postoperatively for presentation of overall results. All cases were treated by means of the all-inside arthroscopic repair technique using a FasT-Fix meniscal repair device. Results Twenty patients were followed up for an average of 60 weeks. The mean age of the patients was 20.95 ± 1.60 years; the average suture used was 2.85; 70% had isolated meniscal injury, and 30% had associated anterior cruciate ligament (ACL) tear; the average tear length was 1.91 cm. The mean preoperative and postoperative Lysholm scores were 38.25 and 91.20, respectively. The mean preoperative and postoperative IKDC subjective evaluation results were 31.28 and 91.44, respectively. The preoperative IKDC objective evaluation results revealed 16 (80%) patients with severely abnormal knees (grade D) and four (20%) patients with abnormal knees (grade C). The postoperative IKDC objective evaluation results revealed two (10%) patients with abnormal knees (grade C), three (15%) patients with nearly normal knees (grade B), and 15 (75%) patients with normal knees (grade A). There is better improvement in scores if ACL reconstruction is performed simultaneously with meniscal repair, the procedure is performed for vertical longitudinal tears, the tear is in the 'red-red' zone, and the tear length is less than 21 mm. There were no differences in functional results on the basis of repair of medial meniscus or lateral meniscus, acute or chronic injuries, or age. Conclusion Better outcome of meniscal repair was seen in patients with vertical longitudinal tear in the red-red zone with a tear length of less than 21 mm and associated with ACL reconstruction.

Analysis of “Hidden Lesions” of the Extra-articular Biceps After Subpectoral Biceps Tenodesis

Background: In biceps tenodesis for intra-articular tears, determining the distal extension of the lesions through the biceps groove is important in choosing the optimal tenodesis site. Purpose: To determine the optimal tenodesis site by analyzing the extension and delamination of an extra-articular lesion, or a “hidden lesion,” in the retrieved biceps after subpectoral biceps tenodesis. Study Design: Case series; Level of evidence, 4. Methods: A total of 36 subpectoral tenodeses were performed, and the retrieved biceps were analyzed. The biceps lesions were divided into zones according to their location as follows: the proximal intra-articular (zone A), middle intragroove (zone B), and distal extra-articular portions (zone C); the lesions in zones B and C were called “hidden lesions.” The length and delamination depth of the biceps tears were examined, and the severity of the accompanying tenosynovitis and degeneration was assessed. Results: Tears invaded zone B in all the cases and extended to zone C in 28 cases (77.8%). Tenosynovitis was observed along the tear in 28 cases (77.8%) and extended to zone C in 26 cases (72.2%). The mean tear length in the hidden lesions, including the tear and tenosynovitis, was 34.2 mm. Degenerative changes in the proximal intra-articular and middle intragroove portions were observed in all the cases and up to the distal extra-articular portion in 29 cases (80.6%). Conclusion: In approximately 80% of the intra-articular biceps tears evaluated in this study, a “hidden lesion” was observed going beyond the bicipital groove and extending to the distal extra-articular portion. Therefore, the subpectoral portion may be considered the optimal tenodesis site for the complete removal of all hidden biceps lesions.

Factors Predicting Rotator Cuff Retears

Background: The rate of retears after rotator cuff repair varies from 11% to 94%. A retear is associated with poorer subjective and objective clinical outcomes than intact repair. Purpose: This study was designed to determine which preoperative and/or intraoperative factors held the greatest association with retears after arthroscopic rotator cuff repair. Study Design: Cohort study; Level of evidence, 3. Methods: This study retrospectively evaluated 1000 consecutive patients who had undergone a primary rotator cuff repair by a single surgeon using an arthroscopic inverted-mattress knotless technique and who had undergone an ultrasound evaluation 6 months after surgery to assess repair integrity. Exclusion criteria included previous rotator cuff repair on the same shoulder, incomplete repair, and repair using a synthetic polytetrafluoroethylene patch. All patients had completed the modified L’Insalata Questionnaire and underwent a clinical examination before surgery. Measurements of tear size, tear thickness, associated shoulder injury, tissue quality, and tendon mobility were recorded intraoperatively. Results: The overall retear rate at 6 months after surgery was 17%. Retears occurred in 27% of full-thickness tears and 5% of partial-thickness tears (P < .0001). The best independent predictors of retears were anteroposterior tear length (correlation coefficient r = 0.41, P < .0001), tear size area (r = 0.40, P < .0001), mediolateral tear length (r = 0.34, P < .0001), tear thickness (r = 0.29, P < .0001), age at surgery (r = 0.27, P < .0001), and operative time (r = 0.18, P < .0001). These factors produced a predictive model for retears: logit P = (0.039 × age at surgery in years) + (0.027 × tear thickness in %) + (1 × anteroposterior tear length in cm) + (0.76 × mediolateral tear length in cm) – (0.17 × tear size area in cm2) + (0.018 × operative time in minutes) –9.7. Logit P can be transformed into P, which is the chance of retears at 6 months after surgery. Conclusion: A rotator cuff retear is a multifactorial process with no single preoperative or intraoperative factor being overwhelmingly predictive of it. Nevertheless, rotator cuff tear size (tear dimensions, tear size area, and tear thickness) showed stronger associations with retears at 6 months after surgery than did measures of tissue quality and concomitant shoulder injuries.

Outcomes After Repair of Chronic Bucket-Handle Tears of Medial Meniscus

The purpose of this study was to determine the outcomes after repair of chronic bucket-handle medial meniscal tears by use of magnetic resonance imaging, clinical examination, and patient-reported outcomes. A retrospective review of patients with chronic bucket-handle medial meniscal tears that had been repaired with meniscal sutures was undertaken. The following criteria for inclusion were adopted: minimum tear length of 2cm and chronic medial meniscal tear identified at the time of arthroscopy. The tears were susceptible to dislocation with probing. Data collected included demographic, clinical, radiologic, and surgical data. Postoperative healing was assessed with the clinical criteria of Barrett etal. The International Knee Documentation Committee rating, Lysholm score, and Tegner activity level were determined, and postoperative magnetic resonance imaging was used to evaluate healing in accordance with the criteria of Henning etal. Twenty-four patients fulfilled the inclusion criteria. The mean time from injury to surgery was 10months (range, 2 to 60months). Sixteen patients underwent anterior cruciate ligament reconstruction, 1 patient underwent posterior cruciate ligament reconstruction, and 6 patients underwent meniscus repair only. A median of 5 sutures (range, 3 to 6 sutures) were used for repair. Four cases (all of which had undergone meniscus repair only) required revision. Complete healing was achieved in 83% of cases according to the criteria of Barrett etal. The mean follow-up time was 48months (range, 24 to 112months). An International Knee Documentation Committee rating of A or B was achieved in the 20 patients who did not require revision. The median Lysholm score was 95 (range, 92 to 100). The median Tegner activity level before injury was 7, and it remained unchanged after surgery in all cases. This study showed that repair of chronic bucket-handle meniscal tears can lead to good clinical outcomes and a relatively low (17%) failure rate. In addition, repairs of isolated meniscal tears had a significantly higher risk of failure than repairs performed in conjunction with anterior cruciate ligament reconstruction. Level IV, therapeutic case series.

Analysis of displacement and deformation of the medial meniscus with a horizontal tear using a three-dimensional computer model

The displacement and deformation of the knee meniscus significantly affect its roles; however, little is known about the displacement and deformation patterns of a torn medial meniscus. The objective of this study was to evaluate quantitatively the patterns of displacement and deformation in horizontally torn medial menisci during knee flexion. Twenty patients with horizontally torn medial menisci underwent three-dimensional (3-D) magnetic resonance imaging at varying degrees of knee flexion, and 3-D computer models of the tibia, tibial articular cartilage, and meniscus were generated. Based on these, the size of the horizontal tear (% tear) was evaluated and defined as the circumferential ratio between the length of the horizontal tear and that of the entire meniscus. The 3-D meniscus models were automatically superimposed over images taken at 0, 20, 40, and 60° of knee flexion by the voxel-based registration method. Meniscal motion and deformation during knee flexion were visualized and quantitatively calculated on the mid-sagittal plane. Correlations between the size of horizontal tear, displacement/deformation of torn menisci, and clinical symptoms were evaluated after conservative treatment for 3months. The % tear was 35.7±12.5% (range 13.7-55.5%). During knee flexion, all torn menisci moved posteriorly, with gradual widening of horizontal and vertical gaps (p<0.05). A direct correlation was observed between % tear and change in the vertical tear gap during knee flexion (p<0.05). There was an inverse correlation between Lysholm score and % tear (p<0.05). Medial meniscal horizontal tears widen and deform during knee flexion, and % tear correlates with the change in the vertical gap. Patients with a lower % tear are more capable of performing activities of daily living after conservative treatment. This method may help clarify the cause of pain in patients with medial meniscus tears as well as facilitate the selection of an appropriate treatment plan. Case series, Level IV.

MRI Characteristics of Healed and Unhealed Peripheral Vertical Meniscal Tears

The objective of our study was to retrospectively compare the MRI characteristics of surgically confirmed healed and unhealed peripheral vertical meniscal tears. The study group consisted of 64 patients with 86 peripheral vertical meniscal tears diagnosed on MRI who subsequently underwent knee surgery. The MRI examinations were retrospectively reviewed to assess the following tear characteristics: tear location relative to the meniscocapsular junction, tear width, tear length, tear extension through one or both surfaces, sequences on which tear was visualized, signal intensity of tear on T2-weighted imaging, and presence of low-signal-intensity strands bridging the tear on T2-weighted imaging. Multivariate logistic regression models were used to determine whether MRI characteristics could be used to distinguish between healed and unhealed tears at surgery. Tear location was the most significant characteristic (p<0.001) for distinguishing between healed and unhealed tears: 17 of 18 (94.4%) tears located at the meniscocapsular junction of the medial meniscus were healed and 15 of 68 (22.1%) tears not located at the meniscocapsular junction were healed. For tears not located at the meniscocapsular junction, MRI characteristics significantly associated with healed tears included a tear width of less than 2 mm (p=0.01), tear visualized only on intermediate-weighted imaging (p=0.01), tear showing intermediate or bright signal intensity on T2-weighted imaging (p=0.06), and low-signal-intensity strands bridging the tear on T2-weighted imaging (p<0.001). Most peripheral vertical tears at the meniscocapsular junction of the medial meniscus spontaneously heal. The MRI characteristics of tears not located at the meniscocapsular junction can help distinguish between healed and unhealed tears.

Characteristics of small to medium-sized rotator cuff tears with and without disruption of the anterior supraspinatus tendon

The purpose of this study was to examine the baseline function and results of arthroscopic cuff repair in shoulders with small and medium-sized full-thickness cuff tears with complete supraspinatus disruption compared with those with an intact anterior supraspinatus tendon. The study evaluated 112 subjects with small and medium-sized cuff tears. Subjects were grouped according to anterior supraspinatus integrity (83 shoulders intact, group 1; and 29 shoulders with anterior supraspinatus tendon disruption, group 2). Functional assessments included visual analogue scale for pain, American Shoulder and Elbow Surgeons (ASES) score, Simple Shoulder Test score, and Constant score. Repair integrity was assessed by ultrasound examination. Group 2 shoulders had greater mean tear width, length, and area (P < .0001) and greater supraspinatus muscle degenerative changes (P < .0001) compared with shoulders with an intact anterior supraspinatus tendon. There were no differences in demographics or baseline function (ASES score: 45 group 1 vs 46 group 2, P = .79; Constant score: 56 group 1 vs 52 group 2, P = .29) before surgery. There were no differences in any functional parameter (ASES score: 92 group 1 vs 93 group 2, P = .71; Constant score: 84 group 1 vs 85 group 2, P = .84) after surgery. There was no difference in tendon healing rates (93% group 1 vs 86% group 2; P = .26). In the setting of painful small and medium-sized rotator cuff tears, disruption of the anterior supraspinatus tendon was associated with greater tear size and more advanced supraspinatus muscle degeneration. However, anterior supraspinatus tendon integrity had no influence on the clinical presentation or the functional and structural results of cuff repair surgery.

Human autopsy study of drug-eluting stents restenosis: histomorphological predictors and neointimal characteristics

Restenosis in drug-eluting stents (DESs) occurs infrequently, however, it remains a pervasive clinical problem. We interrogated our autopsy registry to determine the underlying mechanisms of DES restenosis, and further we investigated the neointimal characteristics of DESs and compared with bare metal stents (BMSs). Coronary lesions from patients with DES implants (n = 82) were categorized into four groups based on cross-sectional area narrowing: patent (<50%), intermediate (50-74%), restenotic (≥ 75% with residual lumen), and total occlusion (organized thrombus within the stent). Restenosis and occlusion were significantly dependent on the total stented length: restenosis (26.7 mm) and occlusion (25.7 mm) compared with patent DESs (17.3 mm). Further, restenotic and occluded lesions were located more distally in the coronary arteries and had greater vessel injury and uneven strut distribution suggesting local drug gradient. Multivariate analysis revealed that normalized maximum inter-strut distance was associated with DES restenosis (OR: 17.4, P = 0.04) while medial tear length was a predictor of DES occlusion (OR: 5.1, P = 0.03). No differences were observed between different DESs (sirolimus-, paclitaxel-, and everolimus-eluting stents) for restenosis and occlusion. Further, neointimal compositions of restenotic DESs demonstrated greater proteoglycan deposition and less smooth muscle cellularity over time, when compared with BMS with greater cell density and collagen deposition. Our study indicates the impacts of inadequate drug concentration due to wider inter-strut distance and vessel injury as primary mechanisms of DES restenosis and occlusion, respectively. Moreover, the differences in neointimal compositions between DESs and BMSs might serve as a potential target for the suppression of late neointima growth via inhibition of proteoglycans in DESs.