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Background: The location of patellar and femoral fixation of the graft in medial patellofemoral ligament reconstructions has been widely discussed. This study aimed to assess the distances between different patellar and femoral fixation points to identify the least anisometric pairs of points., Methods: Ten cadaver knees were attached to an apparatus that simulated an active range of motion of 120°, with three metallic markers fixed onto the medial side of the patella, and seven markings onto the medial epicondyle. The examined points included the proximal patella pole (1), the patellar center (3), the midpoint between points 1 and 3 (2), a point directly on the epicondyle (6), points 5mm anterior (5) and posterior (7) to the epicondyle, points 5mm anterior to point 5 (4) and 5mm posterior to point 7 (8), and points 5mm proximal (9) and distal (10) to the epicondyle. The distances between patella and femur points were measured by a photogrammetry system at 15° intervals., Findings: The pair of points that exhibited the lowest average variability in distance, and hence was the most isometric, was the patella center combined with the anterior to the medial femoral epicondyle. The pairs of points that exhibited the highest average variability in distance, and hence were the least isometric, were the ones located distal or posterior to the medial femoral epicondyle, with less influence by the patellar location., Interpretation: Surgeons should avoid positioning the graft distally or posterior to the epicondyle due to the increase in anisometry., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Objective: To standardize and to develop a fresh osteochondral allograft protocol of procurement, processing and surgical utilization in Brazil. This study describes the steps recommended to make fresh osteochondral allografts a viable treatment option in a country without previous fresh allograft availability., Design: The process involves regulatory process modification, developing and establishing procurement, and processing and surgical protocols., Results: Legislation: Fresh osteochondral allografts were not feasible in Brazil until 2009 because the law prohibited preservation of fresh grafts at tissue banks. We approved an amendment that made it legal to preserve fresh grafts for 30 days from 2°C to 6°C in tissue banks. Procurement: We changed the protocol of procurement to decrease tissue contamination. All tissues were procured in an operating room. Processing: Processing of the grafts took place within 12 hours of tissue recovery. A serum-free culture media with antibiotics was developed to store the grafts. Surgeries: We have performed 8 fresh osteochondral allografts on 8 knees obtaining grafts from 5 donors. Mean preoperative International Knee Documentation Committee (IKDC) score was 31.99 ± 13.4, improving to 81.26 ± 14.7 at an average of 24 months' follow-up. Preoperative Knee Injury and Oseoarthritis Outcome Score (KOOS) score was 46.8 ± 20.9 and rose to 85.24 ± 13.9 after 24 months. Mean preoperative Merle D'Aubigne-Postel score was 8.75 ± 2.25 rising to 16.1 ± 2.59 at 24 months' follow-up., Conclusion: To our knowledge, this is the first report of fresh osteochondral allograft transplantation in South America. We believe that this experience may be of value for physicians in countries that are trying to establish an osteochondral allograft transplant program.

The current study analyzed changes in anterior cruciate ligament (ACL) and lateral collateral ligament stress as a result of mechanical varus. In an exploratory pilot study, progressive mechanical varus was introduced to a male finite element model of the lower limb at different knee flexion angles. Nine situations were analyzed (combinations of 0°, 30°, and 60° knee flexion and 0°, 5°, and 10° varus). The ACL stress was measured via changes in section force, von Mises stress, and fiber stress. Lateral collateral ligament stress was measured via changes in section force. For all 3 measures of the ACL, maximum stress values were found in extension, stress decreased with flexion, and the effect of varus introduction was most significant at 30° flexion. With 60° flexion, varus introduction produced a decrease in section force and von Mises stress and a small increase in fiber stress. In all situations and stress measures except fiber stress at 60° flexion, stress was concentrated at the posterolateral bundle. For the lateral collateral ligament, the introduction of 5° and 10° varus caused an increase in section force at all degrees of flexion. Stress in the ligament decreased with flexion. Mechanical varus of less than 10° was responsible for increased ACL stress, particularly at 0° and 30° knee flexion, and for increased lateral collateral ligament stress at all degrees of flexion. Stress was mostly concentrated on the posterolateral bundle of the ACL. [Orthopedics. 2016; 39(4):e729-e736.]., (Copyright 2016, SLACK Incorporated.)

Background: Recent studies clearly characterize the anatomical parameters of the knee anterolateral ligament (ALL). The potential clinical importance of this ligament is exemplified by some patients with possible combined Anterior Cruciate Ligament (ACL) and ALL rupture who do not progress satisfactorily following isolated ACL reconstruction. Previous biomechanical studies have assessed the resistance parameters of the ALL in order to address potential reconstruction strategies; however, these have reported conflicting results. Thus, this study aimed to evaluate the linear resistance of the ALL by means of a biomechanical study in cadaveric knees., Methods: Fourteen cadaveric knees were used. The ALL was dissected, and all structures that connect the femur and the tibia, except for the ALL, were sectioned. The ALL was subjected to a tensile test with the knee around 30 to 40 degrees, in a way that the ALL was aligned with the machine. The strength at the maximum resistance limit, deformation and stiffness of the ALL were evaluated., Results: The mean maximum strength of the ALL was 204.8 +/- 114.9 N. The stiffness was 41.9 +/- 25.7 N/mm and the deformation 10.3 +/- 3.5 mm., Conclusion: The ALL has a mean ultimate tensile strength of 204.8 N. This suggests that simple bands of all autologous or homologous grafts commonly used in clinical practice for ligament reconstruction around the knee possess the required biomechanical resistance characteristics for ALL reconstruction.

Purpose: This study sought to determine the safety limits for performing a femoral bone tunnel to reconstruct the knee anterolateral ligament (ALL) by establishing its distance from the lateral collateral ligament (LCL) and the popliteus muscle tendon (PT) on the lateral femoral condyle., Methods: Anatomic study on 48 knee cadaveric specimens. The femoral attachments of the studied structures were isolated, and the distance between them was measured. For each cadaver, the percentage of cases in which at least 50 % of the LCL and PT would be injured when using 4- to 12-mm-diameter drills in an ALL reconstruction procedure was evaluated., Results: The LCL and PT were 3.8 mm and 10.2 mm distant from the ALL, respectively. A 4-mm tunnel would cause LCL injury in 8.3 % of cases, with increasing incidence of injury up to 87.5 % with a 12-mm drill. Injury to the PT would start with the 10-mm drill, causing injury in 2.0 % of cases., Conclusions: Performing a tunnel in the center of the ALL may cause an iatrogenic injury to the LCL origin. No cases of PT injury are expected to occur with drills smaller than 10 mm.

Purpose: The aim of this study is to characterize in detail the meniscal insertion of the anterolateral ligament (ALL) of the knee, establishing parameters regarding the circumference of the lateral meniscus and the popliteal muscle tendon (PMT) groove in addition to its histological analysis., Methods: A total of 33 knees of cadavers were dissected. The ALL and the lateral meniscus were removed en bloc. After removal of the anatomical specimen, the meniscus circumference, the ALL insertion points on the external surface of the lateral meniscus, and the PMT groove were measured. Eight menisci were subjected to histological analysis., Results: The ALL was found in all dissections performed. The ALL insertion occurred macroscopically in the transition between the anterior horn and the lateral meniscus body, specifically beginning at 36.0% and ending at 41.9% of the meniscal circumference, occupying a mean area of 5.6 mm. The distance between the end of the ALL meniscal insertion and the beginning of the PMT groove averaged 12.9 mm. In the histological evaluation, in longitudinal sections, we observed dense collagen fibers of the ligament inserting on the external surface of the meniscus. It is possible to observe a spreading of collagen fibers at the moment of meniscal insertion., Conclusions: The ALL meniscal insertion was found in all dissected specimens, beginning with approximately 36% of the meniscal outer diameter, 12.9 mm anterior to the beginning of the PMT groove. The histological analysis confirmed the presence of true ligamentous tissue in the dissected specimens.

Although the medial patellotibial ligament (MPTL) has been neglected regarding its function in patellar stability, recently, its importance in terminal extension and during flexion has been recognized. Indications for reconstruction of the medial patellofemoral ligament combined with the MPTL are extension subluxation, flexion instability, children with anatomic risk factors for patellar instability, and knee hyperextension associated with generalized laxity. We describe a combined reconstruction of the medial patellofemoral ligament with quadricipital tendon and reconstruction of the MPTL with patellar tendon autografts.

Objective: To describe a surgical technique for anatomical reconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon; and to present the initial results from a case series., Method: The proposed technique was used on a series of cases of patients with diagnoses of patellofemoral instability and indications for surgical treatment, who were attended by the Knee Group of HC-IOT, University of São Paulo. The following were evaluated before and after the operation: range of motion (ROM), apprehension test, lateral translation test, patellar inclination test, inverted J sign, subluxation upon extension, pain from compression of the patella and pain from contraction of the quadriceps. After the operation, the patients were asked whether any new episode of dislocation had occurred, what their degree of satisfaction with the surgery was (on a scale from 0 to 10) and whether they would be prepared to go through this operation again., Results: Seven knees were operated, in seven patients, with a mean follow-up of 5.46 months (±2.07). Four patients who presented apprehension before the operation did not show this after the operation. The lateral translation test became normal for all the patients, while the patellar inclination test remained positive for two patients. The patients with an inverted J sign continued to be positive for this sign. Five patients were positive for subluxation upon extension before the operation, but all patients were negative for this after the operation. None of the patients presented any new episode of dislocation of the patella. All of them stated that they were satisfied: five gave a satisfaction score of 9 and two, a score of 10. All of them said that they would undergo the operation again. Only one patient presented a postoperative complication: dehiscence of the wound., Conclusion: Reconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon, was technically safe and presented good objective and subjective clinical results in this case series with a short follow-up.

Objective: To evaluate the results of total knee arthoplasty revisions performed in high complexity cases, with large bone defects or serious ligament deficiencies using a constrained implant hinge associated to a rotating tibial basis., Methods: We evaluated 11 patients in which we used the constrained implant hinge associated to rotating tibial basis, with minimum follow-up of two years. The indications for the procedure included instability, septic loosening, late postoperative infection without loosening and periprosthetic fracture. We evaluated the knee range of movement and functional outcomes by the Knee Society Score (KSS) e Knee Injury and Osteoarthritis Outcome Score (KOOS), besides the presence of complications., Results: All patients achieved 5(o) to 85(o) minimum range of motion at 1 year postoperatively and, in the present evaluation, KSS ranged from 67 to 95. Three patients had no complications until the last evaluation and two patients required implant revision., Conclusion: Despite the complications rate observed, the functional result were acceptable for most patients, and it proved being a viable alternative, especially for patients with low functional demand. Level of Evidence IV, Case Series.

Background: Anatomic and magnetic resonance imaging (MRI) studies have recently characterized the knee anterolateral ligament (ALL). So far, no study has focused on confirming whether the evaluated MRI parameters truly correspond with ALL anatomy., Purpose: To assess the validity of MRI in detecting the ALL using an anatomic evaluation as reference., Study Design: Descriptive laboratory study., Methods: A total of 13 cadaveric knees were subjected to MRI and then to anatomic dissection. Dissection was performed according to previous anatomic study methodology. MRIs were performed with a 0.6- to 1.5-mm slice thickness and prior saline injection. The following variables were analyzed: distance from the origin of the ALL to the origin of the lateral collateral ligament (LCL), distance from the origin of the ALL to its bifurcation point, maximum length of the ALL, distance from the tibial insertion of the ALL to the articular surface of the tibia, ALL thickness, and ALL width. The 2 sets of measurements were analyzed using the Spearman correlation coefficient (ρ) and Bland-Altman plots., Results: The ALL was clearly observed in all dissected knees and MRI scans. It originated anterior and distal to the LCL, close to the lateral epycondile center, and showed an anteroinferior path toward the tibia, inserting between the Gerdy tubercle and the fibular head, around 5 mm under the lateral plateau. The ρ values tended to increase together for all studied variables between the 2 methods, and all were statistically significant, except for thickness (P = .077). Bland-Altman plots showed a tendency toward a reduction of ALL thickness and width by MRI compared with anatomic dissection., Conclusion: MRI scanning as described can accurately assess the ALL and demonstrates characteristics similar to those seen under anatomic dissection., Clinical Relevance: MRI can accurately characterize the ALL in the anterolateral region of the knee, despite the presence of structures that might overlap and thus cause confusion when making assessments based on imaging methods.

Objective: The present study was performed in order to evaluate the use of platelet rich plasma associated to bone marrow aspirate, substituting autologous iliac bone graft in medial opening wedge osteotomy (OWHTO)., Methods: Twenty-five patients were submitted to tibial opening wedge osteotomy, being divided into two groups. Iliac group: 14 patients submitted to OWHTO, using autologous iliac bone graft to fill the gap. PRP group: 11 patients using platelet rich plasma associated to bone marrow aspirate to fill the gap. We evaluated bleeding (hemoglobin and hematocrit levels) and pain (visual analogic scale-VAS), then we compared the groups regarding these variables., Results: Differences between the groups were not found regarding hemoglobin levels (p=0.820) and hematocrit levels (p=0.323). The groups were not different regarding pain measured with VAS (p=0.538)., Conclusion: The use of platelet rich plasma associated to bone marrow aspirate in medial opening wedge osteotomy did not offer advantages over autologous iliac bone graft regarding bleeding and pain.

Distal femoral varus osteotomy is a well-established procedure for the treatment of lateral compartment cartilage lesions and degenerative disease, correcting limb alignment and decreasing the progression of the pathology. Surgical techniques can be performed with a lateral opening-wedge or medial closing-wedge correction of the deformity. Fixation methods for lateral opening-wedge osteotomies are widely available, and there are various types of implants that can be used for fixation. However, there are currently only a few options of implants for fixation of a medial closing-wedge osteotomy on the market. This report describes a medial, supracondylar, V-shaped, closing-wedge distal femoral osteotomy using a locked anterolateral proximal tibial locking plate that fits anatomically to the medial side of the distal femur. This is a great option as a stable implant for a medial closing-wedge distal femoral osteotomy.

Objective: To correlate parameters of implants with incidence of pain., Methods: 32 knees (31 patients) operated on between 2006 to 2008 in a serie of cases of TKA revision surgery were monitored for evidence of pain at the tip of the stem. In all we used uncemented stem Scorpio TS Total Knee ® Revision System (Stryker ®). Criteria assessed: pain in the leg or thigh without other causes, diameter and length of the nail; position of the rod in the medullary canal, intramedullary canal diameter., Results: Mean age was 66.7 years and mean follow-up was 2.6 years.21,87% of patients reported leg pain, 9.37% thigh pain. The group of pacients with leg pain presented with shaft diameter 14.7 mm, length 80 mm in 71.42% and 155 mm in 28,58%, stem diameter/ intramedullary canal diameter average relation of 0,76, 42.8% had stem malalignment. The group without leg pain presented with shaft diameter 15.2 mm, length 80 mm in 68% and 155 mm in 32%, diameters average relation of 0.80, 20.8% had stem malalignment. The group with thigh pain presented with shaft diameter 18.3 mm, length 80 mm in 66.67% and 155 mm in 33,33%,diameters average relation of 0.75, 0% had stem malalignment The group without thigh pain presented with shaft diameter 16.56 mm, length 80 mm in 70.37% and 155 mm in 29,63%, diameters average relation of 0.79, 14,2% had stem malalignment., Conclusion: There was no association between the assessed criteria and pain in the tip of the stem.

Objective: To present a biomechanical device for evaluating medial patellofemoral ligament (MPFL) reconstruction and its isometricity., Methods: An accessible biomechanical method that allowed application of physiological and non-physiological forces to the knee using a mechanical arm and application of weights and counterweights was developed, so as to enable many different evaluations and have a very accurate measurement system for distances between different structures, for analysis on experiments. This article describes the assembly of this system, and suggests some practical applications. Six cadaver knees were studied. The knees were prepared in a testing machine developed at the Biomechanics Laboratory of IOT-HCFMUSP, which allowed dynamic evaluation of patellar behavior, with quantification of patellar lateralization between 0° and 120°. The differences between the distances found with and without load applied to the patella were grouped according to the graft fixation angle (0°, 30°, 60° or 90°) and knee position (intact, damaged or reconstructed)., Results: There was a tendency for smaller lateral displacement to occur at fixation angles greater than 30 degrees of flexion, especially between the angles of 45° and 60° degrees of flexion, after the reconstruction. For the other angles, there was no statistical significance., Conclusion: The method developed is a useful tool for studies on the patellofemoral joint and the MPFL, and has a very accurate measurement system for distances between different structures. It can be used in institutions with fewer resources available.

Purpose: To assess whether the use of an articulated external fixator provides improvements in the mobility, stability and subjective function of patients undergoing ligament reconstruction., Methods: Thirty-three patients with sub-acute and chronic knee dislocation were subjected to multi-ligament reconstruction surgery. These patients were randomly allocated to two groups for immobilization after reconstruction: group 0-control (18 patients), with rigid knee bracing, and group 1-articulated external fixator (15 patients). The stability of the reconstructed ligaments was assessed after at least 14 months (26.6-month average) postoperatively by physical examination. Deficit of extension and flexion was measured in relation to the unaffected contralateral knee, and the Lysholm knee scoring scale questionnaire was applied., Results: There was no difference in the assessment of joint stability between the groups. In group 1, patients showed less flexion deficit (4.8° ± 5.4° vs. 18.2° ± 14.8°, p < 0.05), and the percentage of patients with a flexion deficit of 5° or less were higher compared with group 0 (64 vs. 18 %, p < 0.05). There was no difference between groups in relation to extension loss. Group 1 also presented better Lysholm scores, with 73 % of patients rated as excellent or good compared with 35 % in group 0 (p < 0.05)., Conclusions: Compared with the control rehabilitation protocol with rigid knee bracing in extension, the use of an articulated external fixator in the treatment of chronic multi-ligament-injured knees provided the same ligament stability, better final range of motion and improved Lysholm score. Patients presenting with chronic multi-ligament instability should be considered for articulated external fixation to supplement reconstruction procedures., Level of Evidence: Randomized controlled trial, Level I.

Background: The tibial tubercle-trochlear groove (TT-TG) is used as the gold standard for patellofemoral malalignment., Purpose: To assess 3 patellar tendon-trochlear groove (PT-TG) angle measurement techniques and the PT-TG distance measurement (tendinous cartilaginous TT-TG) as predictors of patellar instability., Study Design: Cohort study (diagnosis); Level of evidence, 3., Methods: Three PT-TG angle measurements and the PT-TG distance were measured in 82 participants with patellar instability and 100 controls using magnetic resonance imaging (MRI). Measurement landmarks were the line tangent to the posterior femoral condyles, the deepest point of the trochlea, the transepicondylar line, and the patellar tendon center. All measurements were recorded once by 1 examiner, and the measurements were recorded twice by 2 examiners in a random group of 100 knees. Mean values and standard deviations (SDs) were obtained. Normality cutoff values were defined as 2 and 3 SDs above the mean in the control group. The sensitivity, specificity, and positive likelihood ratio (LR+) were calculated. Inter- and intrarater reliability were assessed based on the intraclass correlation coefficient (ICC)., Results: The measurements from the patellar instability and control groups, respectively, for angle 1 (16.4° and 8.4°), angle 2 (31° and 15.6°), angle 3 (30.8° and 15.7°), PT-TG distance (14.5 and 8.4 mm), and patellar tilt (21.1° and 7.5°) were significantly different (P < .05). The angle measurements showed greater sensitivity, specificity, and LR+ than the PT-TG distance. Inter- and intrarater ICC values were >0.95 for all measurements., Conclusion: The PT-TG angle and the PT-TG distance are reliable and are different between the patellar instability and control groups. PT-TG angles are more closely associated with patellar instability than PT-TG distance., Clinical Relevance: PT-TG angle measurements show high reliability and association with patellar instability and can aid in the assessment of extensor mechanism malalignment. A more sensitive and specific evaluation of extensor mechanism malalignment can improve patient care by preventing both redislocation and abnormal tracking of overlooked malalignment and complications of unnecessary tibial tuberosity medialization.

Objective: To verify whether the tibial tuberosity-trochlear groove distance (TT-TG) and the tendinous-cartilaginous TT-TG (the distance between the patellar tendon and trochlear groove: PT-TG) are identical using computed tomography (CT) and magnetic resonance imaging (MRI) techniques., Subjects and Methods: The TT-TG and PT-TG distances were measured on the same knee samples by three observers (two measurements per observer) using CT and MRI scans collected retrospectively. The reproducibility of the measurements was assessed using the interclass correlation coefficient (ICC). The means and standard deviations of four measurements were calculated for each patient. A paired t-test was used to assess differences between measurements., Results: Fifty knee samples (32 with patellar instability and 18 with other conditions) were evaluated. The inter- and intraobserver reliability was excellent for all four measurements (>0.8). On average, the TT-TG distance on MRI was 3.1-3.6 mm smaller than that on CT, and the PT-TG distance on MRI was 1.0-3.4 mm larger than the TT-TG distance on MRI., Conclusion: The osseous TT-TG and tendinous-cartilaginous PT-TG distances determined by CT and MRI were not identical.

We present a new technique for the combined intra- and extra-articular reconstruction of the anterior cruciate ligament. Intra-articular reconstruction is performed in an outside-in manner according to the precepts of the anatomic femoral tunnel technique. Extra-articular reconstruction is performed with the gracilis tendon while respecting the anatomic parameters of the origin and insertion points and the path described for the knee anterolateral ligament.

Objective: To analyze occurrences of trochlear dysplasia in patients with Down syndrome in the presence and absence of femoropatellar instability., Methods: Eleven knees with stable patellae and thirteen with unstable patellae in patients with Down syndrome were compared. Radiographs were produced to evaluate patellar height, trochlear angle and femoropatellar congruence angle., Results: The prevalence ratio for a high patella between the unstable and the stable patients was 1.01 using the Insall-Salvati index and 0.68 using the Caton-Deschamps index. For an abnormal congruence angle, the prevalence ratio was 2.04. An increased congruence angle was only found in four cases, all presenting instability., Conclusions: Trochlear dysplasia was only found in cases of instability. The trochlear groove angle and the femoropatellar congruence angle correlated with the presence of patellar instability.

Purpose: A technique for combined reconstruction of the anterior cruciate ligament (ACL) and posterolateral corner (PLC) with a single femoral tunnel was recently described. This technique aims to avoid tunnel confluence in the lateral femoral condyle. Because there have been no studies on the functional outcomes and possible complications of this technique, our goal is to demonstrate a two-year minimum follow-up of patients who underwent this type of reconstruction., Methods: Nine patients were prospectively evaluated. The ACL was reconstructed with an anatomic single bundle, and the PLC structures reconstructed were the lateral collateral ligament, the popliteus tendon, and the popliteofibular ligament. Patients were evaluated using the objective and subjective International Knee Documentation Committee (IKDC) and the Lysholm and Tegner scales before and after the surgical procedure., Results: The mean follow-up period of the studied patients was 27.3 months. The mean subjective IKDC score rose from 43.6 to 84.0, and the Lysholm score rose from 62.1 to 90.8. In the final assessment, six patients were classified as IKDC A and three as IKDC B. According to the Tegner scale, five patients were able to return to their level of activity prior to the injury. There were no reconstruction failures. One patient experienced postoperative infection and pain in the lateral scar., Conclusions: The results of the reconstruction of ACL injuries associated with PLC with a single femoral tunnel produced a good functional outcome and a low incidence of complications.

Objectives: Healing is an event that is fundamental to the success of total knee arthroplasty. The aims of the present study were to compare the rates of complications related to wound healing between two groups of volunteers submitted to total knee arthroplasty and to evaluate the effects of postoperative oxygen supplementation by means of a nasal catheter., Method: A total of 109 patients who underwent total knee arthroplasty were randomized into two groups, namely, groups that did and did not receive postoperative oxygen supplementation via a nasal catheter. The surgical wound was monitored every day during the hospital stay and on the 7th, 14th, 21st, 30th and 42nd postoperative days. Characteristics related to healing were observed, including hyperemia, dehiscence, necrosis, phlyctenules and deep and superficial infection., Results: There were no cases of deep infection. Hyperemia was statistically correlated with the total number of complications in the groups, with oxygen demonstrated to be a protective factor against hyperemia. Approximately 30% of the patients who exhibited hyperemia had other complications, independent of oxygen supplementation., Conclusion: Oxygen supplementation following total knee arthroplasty was shown to be effective in diminishing hyperemia around the operative wound. The development of hyperemia was a precursor to other complications, irrespective of whether oxygen supplementation was used.

Metallosis is an uncommon complication following total knee arthroplasty that leads to osteolysis and implant loosening due to chronic inflammatory reaction. Abrasion between the metallic surfaces of the implant releases metallic debris that interacts with the periprosthetic soft tissues and causes chronic synovitis. Here we present a case of a 65-year-old man who had undergone total knee arthroplasty 10 years ago and developed implant loosening associated with severe metallosis and varus instability. Radiographs show the three typical signs of metallosis: metal-line sign, bubble sign, and cloud sign. This patient was subjected to revision surgery consisting of debridement and primary implant replacement by a hinged endoprosthesis. Knowledge of the typical radiographic and clinical findings of metallosis is important to rapidly diagnose this complication and avoid progressive joint destruction.

Background: Many reconstruction techniques have already been developed for treating posterolateral corner (PLC) injuries, with still no consensus regarding what would be the best option. Some techniques use non-bone tunnel fixation, attaching the graft to the femur using a cortical screw with toothed washer. The main objective of the present study is to evaluate complications related to fixation performed by a screw and toothed washer technique., Methods: A prospective study with surgical reconstruction of the PLC structures of the knee between January 2008 and December 2009 was performed. PLC reconstruction included reconstruction of the lateral collateral ligament, popliteofibular ligament and popliteal muscle tendon. Fixation of the grafts in the femur was achieved by means of a 4.5mm screw with a toothed washer. The assessments were done using the following methods: objective IKDC, subjective IKDC, Lysholm and Tegner. Radiographic evaluations were performed immediately after the operation, at 3, 6 and 12months after surgery, and yearly thereafter. Complications were documented., Results: The mean subjective IKDC score after the operation was 69.2; Lysholm scale was 80.7. Two patients presented failure of reconstructions of the PLC. In the radiographic evaluations, signs of loosening of the screw with toothed washer in the femur were observed in eight cases (66.6%). Six patients (50%) complained of lateral pain after the operation., Conclusion: The technique of femoral fixation was shown to be efficient in restoration of stability. However there was a high rate of complications secondary to implant, such as loosening of the screws and iliotibial tract friction., Level of Evidence: Case series, leve IV., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Injury to the posterolateral corner (PLC) is difficult to diagnose; most lesions of this type are included within the context of complex knee injuries. Study of the posterolateral complex is growing in importance because of the complex instability generated by these injuries. Although various physical examination tests are described for the diagnosis of PLC lesions, in 72% of cases these lesions are not identified at their initial presentation, which shows the difficulty in both performing these tests and interpreting the results. The maneuver described in this report is performed by executing external rotation of the leg. With the thumb of the proximally positioned hand, the examiner evaluates the positioning of the lateral tibial plateau in relation to the femoral condyle. With this maneuver, in lesions of the PLC and particularly lesions of its external rotation-restricting structures, we observe external rotation of the tibia and posterior subluxation of the lateral tibial plateau that cause the anterior edge of the tibial plateau to be posteriorized in relation to the anterior edge of the lateral femoral condyle. The idea behind this maneuver is not to eliminate the use of other tests but, rather, to add it to a diagnostic arsenal that still has interpretation flaws.

Objective: Evaluate the correlation between magnetic resonance imaging, clinical examination and intraoperative identification of posterolateral corner injuries of the knee., Methods: We compared the findings of physical examination under anesthesia and intraoperative findings as the gold standard for the posterolateral corner injury with the reports of the MRIs of patients who underwent reconstruction of the posterolateral corner. Thus, we evaluated the use of MRI for the diagnosis of lesions., Results: We found a sensitivity of 100% in lesions of the anterior cruciate ligament (ACL), 86.96% in lesions of the posterior cruciate ligament (PCL), 57.58% in lesions of the lateral collateral ligament (LCL) and 24.24 % in tendon injuries of the popliteal muscle (PMT)., Conclusion: Posterolateral corner injury is difficult to visualize and interpret; therefore, MRI imaging should not be used alone for diagnosis.

Background: Reconstruction of the anterior cruciate ligament (ACL) is one of the most common procedures in orthopaedic surgery. However, even with advances in surgical techniques and implants, some patients still have residual anterolateral rotatory laxity after reconstruction. A thorough study of the anatomy of the anterolateral region of the knee is needed., Purpose: To study the anterolateral region and determine the measurements and points of attachments of the anterolateral ligament (ALL)., Study Design: Descriptive laboratory study., Methods: Dissections of the anterolateral structures of the knee were performed in 20 human cadavers. After isolating the ALL, its length, thickness, width, and points of attachments were determined. The femoral attachment of the ALL was based on the anterior-posterior and proximal-distal distances from the attachment of the lateral collateral ligament (LCL). The tibial attachment point was based on the distance from the Gerdy tubercle to the fibular head and the distance from the lateral tibial plateau. The ligaments from the first 10 dissections were sent for histological analysis., Results: The ALL was found in all 20 knees. The femoral attachment of the ALL at the lateral epicondyle averaged 3.5 mm distal and 2.2 mm anterior to the attachment of the LCL. Two distal attachments were observed: one inserts into the lateral meniscus, the other between the Gerdy tubercle and the fibular head, approximately 4.4 mm distal to the tibial articular cartilage. The mean measurements for the ligament were 37.3 mm (length), 7.4 mm (width), and 2.7 mm (thickness). The histological analysis of the ligaments revealed dense connective tissue., Conclusion: The ALL is consistently present in the anterolateral region of the knee. Its attachment to the femur is anterior and distal to the attachment of the LCL. Moving distally, it bifurcates at close to half of its length. The ALL features 2 distal attachments, one at the lateral meniscus and the other between the Gerdy tubercle and the fibular head., Clinical Relevance: The ALL may be important in maintaining normal rotatory limits of knee motion; ALL rupture could be responsible for rotatory laxity after isolated intra-articular reconstruction of the ACL.

Objective: To evaluate the results obtained using local myocutaneous rotation flaps in cases of wound dehiscence after total knee arthroplasty., Methods: Patients undergoing these surgical procedures were selected in the 2000-2012 period. The nine selected cases during this period were subjected to flap coverage due to skin dehiscence associated with infection. In eight cases we used rotation flaps of the medial gastrocnemius, and in one case we used advancing skin., Results: Eighty nine percent of the cases were successful in the coverage of the prosthesis and the viability of the flaps. In four cases it was possible to maintain or review the prosthesis. Four other cases progressed to amputation due to failure on treatment of infections, and one case remained without the prosthesis. The functional evaluation showed an unsatisfactory outcome in 89% of cases., Conclusion: Coverage flaps are a good option for the treatment of cases of dehiscence with exposure of the prosthesis and the functional failure was associated with the inability to control the infection and the damage it caused. Level of Evidence IV, Case Series.

Objective: To show our experience with press-fit cementless stem and metaphyseal fixation with cement in a selected series of patients who underwent revision total knee arthroplasty., Methods: Thirty-four patients (35 knees) underwent revision total knee arthroplasty using the press-fit technique. Minimum follow-up was one year (mean 2.2 years) with a maximum length of three years., Results: Of 34 patients, 20 were women and 14 were men. There was one death due to causes not related to arthroplasty and one patient dropout. There were no cases in which further review was necessary. Patients who underwent revision had clinical and functional improvement demonstrated by the results of the KSS, results of the SF-36 quality of life questionnaire, through gains in range of motion and improved limb alignment., Conclusion: There was postoperative clinical and functional improvement in comparison to the preoperative status in revision total knee arthroplasty with press-fit cementless stem. Level of Evidence IV, Case series.

Objective: To analyze the experience with allograft transplantation of the extensor mechanism in total knee arthroplasty and compare results with the international experience., Methods: We retrospectively evaluated three cases of extensor mechanism allograft after total knee arthroplasty performed in our hospital with the aid of one of the few tissue banks in Brazil and attempt to establish whether our experiences were similar to others reported in the world literature regarding patient indication, techniques, and outcomes., Results: Two cases went well with the adopted procedure, and one case showed bad results and progressed to amputation. As shown in the literature, the adequate tension of the graft, appropriate tibial fixation and especially the adequate patient selection are the better predictors of good outcomes. Previous chronic infection can be an unfavorable predictor., Conclusion: This surgical procedure has precise indication, albeit uncommon, either because of the rarity of the problem or because of the low availability of allografts, due to the scarcity of tissue banks in Brazil. Level of Evidence IV, Case Series.

Objective: To evaluate whether hemostasis with eletrocauterization in comparison with Floseal((r)) leads to different bleeding rates during total knee arthroplasty., Methods: A COMPARATIVE STUDY WAS PERFORMED BETWEEN TWO GROUPS: group with ten consecutive total knee arthroplasties with Floseal((r)) used as hemostatic method and control group with ten consecutive total knee arthroplasties with eletrocauterization as hemostatic method. Bleeding parameters such as debit of the drain, liquid infusion and blood transfusion rate were recorded., Results: Floseal((r)) group received less blood transfusion, less liquid infusion and lower drainage in absolute numbers compared to the control group. However, no parameter was statistically significant., Conclusion: Hemostasis with Floseal((r)) is as effective as hemostasis with eletrocauterization, what makes it a viable alternative to patients with contraindication to electric scalpel use. Level of Evidence II, Prospective Comparative Study.

Objective: To translate, culturally adapt and validate the "Knee Society Score"(KSS) for the Portuguese language and determine its measurement properties, reproducibility and validity., Methods: We analyzed 70 patients of both sexes, aged between 55 and 85 years, in a cross-sectional clinical trial, with diagnosis of primary osteoarthritis ,undergoing total knee arthroplasty surgery. We assessed the patients with the English version of the KSS questionnaire and after 30 minutes with the Portuguese version of the KSS questionnaire, done by a different evaluator. All the patients were assessed preoperatively, and again at three, and six months postoperatively., Results: There was no statistical difference, using Cronbach's alpha index and the Bland-Altman graphical analysis, for the knees core during the preoperative period (p =1), and at three months (p =0.991) and six months postoperatively (p =0.985). There was no statistical difference for knee function score for all three periods (p =1.0)., Conclusion: The Brazilian version of the Knee Society Score is easy to apply, as well providing as a valid and reliable instrument for measuring the knee score and function of Brazilian patients undergoing TKA., Level of Evidence: Level I - Diagnostic Studies- Investigating a Diagnostic Test- Testing of previously developed diagnostic criteria on consecutive patients (with universally applied 'gold' reference standard).

Objectives: Determine the stability of tibial and femoral components of 20 cementless knee arthroplasties with rotating platform., Methods: The 20 patients (20 knees) underwent an analysis of dynamic radiographs with an image amplifier and maneuvers of varus and valgus which were compared to static frontal and lateral radiographs of the knees and analyzed by two experienced surgeons in a double-blind way., Results: We could observe in this study that both methods showed very similar results for the stability of the tibial and femoral components (p<0.001) using the Kappa method for comparison., Conclusion: The tibial component was more unstable in relation to the femoral component in both static and dynamic studies. Level of Evidence IV, Case Series.

Eight patients, aged 37-50 years, with chronic anterior cruciate ligament (ACL) deficiency, medial compartment osteoarthritis and varus deformity underwent simultaneous arthroscopic ACL reconstruction and open-wedge high tibial osteotomy controlled by a computer navigation system. Despite preoperative planning, the surgeon may need to choose a different osteotomy site during the procedure, invalidating the previous plans. The intraoperative wire control for osteotomies is not precise. The navigation system can help obtain precise alignment during high tibial osteotomy. The average preoperative mechanical axis was 7.5 of varum (sd±1.17°), the average postoperative axis was 1.2° of valgus (sd±1.04°) (p<0.01), and the average correction of the mechanical axis was 8.7° (sd±0.76°). The site of the osteotomy was 3.9 cm (3.5-4.8 cm, sd±0.35 mm) from the articular line, with an inclination of 27.9° (24-35, sd±4.8). The simultaneous use of these procedures allowed proper correction of the knee axis during the surgery. The surgery can be performed concomitantly with ACL reconstruction., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Objective: Platelet-rich plasma (PRP) has the capacity to improve the bone-healing process. The aim of this pilot study was to investigate the occurrence of bone healing and the time taken to achieve this in patients submitted to medial opening wedge high tibial osteotomy (MOWHTO), comparing platelet-rich plasma with bone marrow aspirate to autologous iliac graft., Design: Twenty-five patients who underwent tibial osteotomy were randomly divided into 2 groups: a control group, which received autologous iliac grafts (14 patients), and a study group, which received a compound of PRP and bone marrow aspirate (11 patients)., Results: The bone-healing rates achieved were 100% in the control group and 91% in the study group. There was no difference in the time taken to achieve bone healing between the groups., Conclusions: The use of a combination of PRP and bone marrow aspirate, as a bone substitute, did not demonstrate any advantage over the use of an autologous iliac graft in MOWHTO.

The aim of this study was to estimate the additional cost of treatment of a group of nosocomial infections in a tertiary public hospital. A retrospective observational cohort study was conducted by means of analyzing the medical records of 34 patients with infection after total knee arthroplasty, diagnosed in 2006 and 2007, who met the criteria for nosocomial infection according to the Centers for Disease Control and Prevention. To estimate the direct costs of treatment for these patients, the following data were gathered: length of hospital stay, laboratory tests, imaging examinations, and surgical procedures performed. Their costs were estimated from the minimum values according to the Brazilian Medical Association. The estimated cost of the antibiotics used was also obtained. The total length of stay in the ward was 976 days, at a cost of US$ 18,994.63, and, in the intensive care unit, it was 34 days at a cost of US$ 5,031.37. Forty-two debridement procedures were performed, at a cost of US$ 5,798.06, and 1965 tests (laboratory and imaging) were also performed, at a cost of US$ 15,359.25. US$ 20,845.01 was spent on antibiotics and US$ 1,735.16 on vacuum assisted closure therapy, microsurgical flaps, implant removal, spacer use, and surgical revision. The total additional cost of these cases of hospital infection in 2006 and 2007 was of US$ 91,843.75. Based on that, we demonstrate that the high cost of treatment for hospital infections emphasizes the importance of taking measures to prevent and control hospital infection.

Introduction: Patellofemoral instability is a common knee disease. Its etiology is complex and variable, with many components making different contributions in each individual, resulting in several distinct clinical presentations. Our goal was to analyze the results of surgical treatment in our hospital over a period of 10 years., Patients and Methods: We analyzed 55 knees of 47 patients who underwent surgery for patellofemoral instability and were classified into 2 main groups: proximal realignment and combined proximal and distal realignment. Three other groups were analyzed according to the duration of preoperative symptoms: less than 1 year (group I); 1 to 10 years (group II); and more than 10 years (group III)., Results: There were 62% good results overall, with 78% good results in groups I and II. Group III had 81% bad results, showing that a late diagnosis of advanced disease results in a poor prognosis. In addition to late diagnosis, bad results were usually associated with incorrect diagnosis or choice of surgical technique. There was no significant difference between isolated proximal realignment and combined proximal and distal realignment in groups I or II, but in group III, the combined technique yielded better results., Discussion: Our results indicate that patellofemoral instability should be addressed in its early stages. Patients with long-lasting symptoms or more severe disease seem to achieve better results with combined techniques., Conclusion: Proximal and distal realignments produce better results than isolated proximal realignment in patients with joint degeneration or with greater duration of disease. The realignment surgery does not produce good results in patients with advanced disease.