MRI of the Morel-Lavallée lesion - a case series.

INTRODUCTION: The aim of the study was to review the appearances of Morel-Lavallée (ML) lesions on magnetic resonance imaging (MRI). PATIENTS AND METHODS: 14 patients diagnosed with the ML lesion on MRI were analysed retrospectively (mean age = 35 years). Mechanism of injury, time frame from injury to MRI, location, shape, T1 and proton-density fat-suppression (PDFS) signal intensity (SI), presence of a (pseudo)capsule, septations or nodules within the collection, mass effect and fluid-fluid levels were analyzed. The Mellado and Bencardino classification was utilized to classify the lesions. RESULTS: In most cases, mechanism of injury was distortion. Mean time frame between the injury and MRI was 17 days. Lesions were located around the knee in 9 patients and in the peritrochanteric region in 5 patients. Collections were fusiform in 12 patients and oval in 2 patients. 9 collections were T1 hypointense and PDFS hyperintense. 4 collections had intermediate T1 and high PDFS SI. 1 collection had intermediate T1 and PDFS SI. (Pseudo)capsule was noted in 3 cases. Septations or nodules were found in 4 cases. According to the Mellado and Bencardino, collections were classified as seroma (type 1) in 9, subacute hematoma (type 2) in 1 and chronic organizing hematoma (type 3) in 4 cases. CONCLUSIONS: Characteristic features of ML lesion include a fusiform fluid collection between the subcutaneous fat and the underlying fascia after shearing injury. Six types can be differentiated on MRI, with the seroma, the subacute hematoma and the chronic organizing hematoma being the commonest.

The Posterolateral Instability Score (PoLIS) of the knee joint: a guideline for standardized documentation, classification, and surgical decision-making.

PURPOSE: There has been a recent resurgence in interest in posterolateral instabilities of the knee joint. As this terminology comprises a large variety of pathologies, confusion and ambiguity in communication between surgeons and allied health professionals are generated. Consequently, accurate classification criteria are required to account for thorough preoperative diagnostics, surgical decision-making, and a standardized scientific documentation of injury severity. METHODS: A working group of five knee surgeons, who retrospect more than 2000 reconstructions of the posterolateral corner (PLC) at the minimum, was founded. An advanced PubMed search was conducted to identify key definitions. After defining an accurate diagnostic work-up, popular consensus was reached on definitions and covariates for a novel classification, rating of injury severity, and the resulting surgical decision-making. RESULTS: Three columns (lateral instability, cruciate ligament involvement, and relevant covariates), each ranging from A to D with increasing severity and assigning a number of points, were needed to meet the requirements. The generated terminology translated into the Posterolateral Instability Score (PoLIS) and the added number of points, ranging from 1 to 18, depicted the injury severity score. CONCLUSION: The presented classification may enable an objective assessment and documentation of the injury severity of the inherently complex pathology of injuries to the lateral side of the knee joint. LEVEL OF EVIDENCE: V.

Multiple Ligament Knee Injuries: Does the Knee Dislocation Classification Predict the Type of Surgical Management?

This study aims to evaluate relationships among multiple ligament knee injury (MLKI) patterns as classified according to the knee dislocation (KD) classification and the types of surgical management pursued. We hypothesized that the KD classification would not be predictive of the types of surgical management, and that categorizing injuries according to additional injury features such as structure, chronicity, grade, and topographic location would be predictive of the types of surgical management. This is a Retrospective cohort study. This study was conducted at a level I trauma center with a 150-mile coverage radius. Query of our billing database was performed using combinations of 43 billing codes (International Classification of Diseases [ICD] 9, ICD-10, and Current Procedural Terminology) to identify patients from 2011 to 2015 who underwent operative management for MLKIs. There were operative or nonoperative treatment for individual ligamentous injuries, repair, or reconstruction of individual ligamentous injuries, and staging or nonstaging or nonstaging of each surgical procedure. The main outcome was the nature and timing of clinical management for specific ligamentous injury patterns. In total, 287 patients were included in this study; there were 199 males (69.3%), the mean age was 30.2 years (SD: 14.0), and the mean BMI was 28.8 kg/m2 (SD: 7.4). There were 212 injuries (73.9%) categorized as either KD-I or KD-V. The KD classification alone was not predictive of surgery timing, staging, or any type of intervention for any injured ligament (p > 0.05). Recategorization of injury patterns according to structure, chronicity, grade, and location revealed the following: partial non-ACL injuries were more frequently repaired primarily (p < 0.001), distal medial-sided injuries were more frequently treated operatively than proximal medial-sided injuries (odds ratio [OR] = 24.7; p <0.0001), and staging was more frequent for combined PCL-lateral injuries (OR = 1.3; p = 0.003) and nonavulsive fractures (OR = 1.2; p = 0.0009). The KD classification in isolation was not predictive of any surgical management strategy. Surgical management was predictable when specifying the grade and topographic location of each ligamentous injury. This is a Level IV, retrospective cohort study.

Development of a Core Set for Knee Dysfunction Based on the International Classification of Functioning, Disability and Health: A Cross-sectional Study.

OBJECTIVE: To develop an International Classification of Functioning, Disability and Health core set for patients with knee dysfunction. DESIGN: Cross-sectional study. SETTING: The study was conducted at all levels of care (general community, primary care units, rehabilitation clinics/centers, hospital). PARTICIPANTS: Participants (N=388) with knee dysfunction with or without clinical diagnosis of knee pathology, with or without complaint of pain, with or without instability, and/or with or without knee movement restriction of any type. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Participants were assessed using the core sets for acute and postacute musculoskeletal conditions, the subjective form from the International Knee Documentation Committee scale, the self-report of general health and functionality, and the general health and functionality classified by the researcher. To identify the categories that best explain knee dysfunction, linear regression analyses were performed. RESULTS: Twenty-four categories were identified from the 75 core set categories for acute and postacute musculoskeletal conditions. Eleven categories belong to the component body functions, 3 represent body structures, 7 represent activities and participation, and 3 represent environmental factors. CONCLUSIONS: A core set for knee dysfunction that can be used at all levels of health care was proposed, which offers a system for disability assessment related to knee dysfunction, including environmental and social factors. These factors are important for a broad assessment because they include the multiple aspects of functionality, usually not considered in other knee dysfunction assessment instruments. Further analysis of the content and construct validity of the core set is required.

Valor diagnóstico de las clasificaciones outerbridge e ICRS para la clasificación artroscópica de lesiones condrales de rodilla / Diagnostic value of outerbridge and ICRS classifications for arthroscopic grading of chondral lesions in the knee

OBJETIVOS: Determinar el rendimiento de las clasificaciones de Outerbridge (OB) e International Cartilage Repair Society (ICRS). MÉTODO: Estudio de test diagnóstico, diseño y recolección de datos prospectivo. Siete traumatólogos sub-especialistas observaron un mismo video donde se exponían 30 lesiones condrales bajo visión artroscópica, para luego clasificarlas según OB e ICRS y consignar el tratamiento de elección para cada una de las lesiones, eligiendo entre 6 alternativas: observación, debridamiento mecánico o térmico, microfractura, OATS o terapias biológicas. Tras 7 días, los evaluadores debían repetir el mismo procedimiento. RESULTADOS: La concordancia entre los observadores fue débil para clasificación de ICRS (k 0,25 p < 0,001) y moderada para la clasificación de OB (k 0,45 p < 0,001). La concordancia intra-observador para ICRS oscilaba entre moderada y excelente (k promedio de 0,67), y para la clasificación de OB entre buena y excelente (k promedio 0,83). Ninguna de las dos clasificaciones mostró correlación con la experiencia del cirujano. En la elección de tratamiento, la concordancia entre observadores fue débil (k 0,33 p < 0,001), sin embargo, la concordancia intra-observador fue en todos los casos buena o excelente (k 0,82), mostrando una correlación directamente proporcional a la experiencia del cirujano. La capacidad de discriminación terapéutica, evaluada mediante una regresión logística, mostró un área bajo la curva roc en el rango del no-efecto. CONCLUSIÓN: Ambas clasificaciones mostraron una baja correlación inter-observador y una elevada concordancia intra-observador. En ambas categorías, Outerbridge fue más concordante que ICRS. En cuanto al tratamiento, ninguna de las dos clasificaciones logra unificar criterios quirúrgicos. NIVEL DE EVIDENCIA: Nivel I (test diagnóstico).

OBJECTIVES: Assess de diagnostic accuracy of Outerbridge (OB) and ICRS (International Cartilage Repair Society) classifications. METHODS: We performed a diagnostic test study, with a prospective design and data collection. Seven knee surgeons were asked to observe a video were the 30 chondral lesions were shown through arthroscopic view. Simultaneously they were asked to classify them according to OB and ICRS. Besides, they had to define how they would manage the chondral lesion, choosing among six treatment options (observation, mechanical or thermic chondroplasty, microfracture, osteochondral autologous transfer system (OATS) or biological therapies). A week later, they repeated the same procedure. Intra and interobserver agreement were characterized by κ statistical analysis, and a logistic regression was used to assess the ability of both classifications to discriminate among treatment options. P values < 0,05 were considered significant. RESULTS: Interobserver agreement was weak (κ 0.25 p < 0.001) for ICRS classification and moderate for OB classification (κ 0.45 p < 0.001). Intraobserver agreement for ICRS ranged from moderate to excellent (average κ of 0.67), and for the OB classification ranged from good to excellent (average kappa 0.83). Neither classification correlated with the surgeon's experience. Interobserver agreement for therapeutic choice was poor (κ 0.33 p < 0.001). However, intraobserver agreement was good to excellent (κ 0.82) in all cases, showing a direct correlation with the surgeon's experience. Logistic regression used to assess the ability of both classifications to discriminate among treatment options, showed in both cases an area under the roc curve in the no-effect range. CONCLUSION: Both classifications showed low interobserver and high intraobserver agreements for arthroscopic grading of chondral lesions. In both, Outerbridge was more reliable than ICRS. As for guiding therapeutic management, none of the classifications could unify surgical criteria.

Tibial tubercle avulsion fractures in children.

PURPOSE OF REVIEW: To summarize and discuss the fundamentals of pediatric tibial tubercle avulsion fractures (TTAFs) including preferred imaging modalities, systems for fracture classification, frequently associated injuries, treatment options, outcomes, and common complications. RECENT FINDINGS: Although TTAFs amount to fewer than 1% of all physeal injuries in children, the incidence is increasing, likely because of greater participation in high-level athletics. SUMMARY: TTAFs tend to occur in adolescents nearing skeletal maturity who engage in sports with repetitive jumping. The most popular classification system was proposed by Ogden, which defines five fracture types based on the fracture pattern and extent of fragment displacement. Treatment can be nonsurgical or surgical, and indications depend on fracture type. Most fractures are surgical candidates and can be repaired with open reduction and internal fixation (ORIF) or arthroscopy. Arthroscopic approaches can reveal associated soft tissue injuries, such as meniscal tears, and confirm articular reduction. The most common postoperative complication is irritation because of hardware. With proper treatment, both nonsurgical and surgical outcomes are excellent. TTAFs have high rates of union and patients typically return to sports.

Magnetic resonance imaging of impingement and friction syndromes around the knee.

The knee is a complex joint with its function dependent on a combination of osseous and soft tissue structures. Alteration in the relationship of these tissues, due to either acute or chronic repetitive injury with possible underlying congenital predisposing factors, can result in impingement between the structures resulting in pain, particularly on activity. The purpose of this article is to provide a comprehensive review of the MRI features of various impingement syndromes around the knee.

Etiology of knee pain in elite cyclists: A 14-month consecutive case series.

Overuse injuries of the knee are a common cause of missed training and competition days in elite cyclists, however the underlying conditions causing this knee pain are not well defined. We conducted a diagnostic study, investigating a consecutive series of 53 high level cyclists with non-traumatic knee pain over a 14 month period. Demographic data on the participants' cycling specialty and training level was noted. Clinical information concerning knee pain intensity, location and occurrence were collected using a questionnaire. Our results show 7 different overuse injuries were identified. The prepatellar friction syndrome accounted for the majority of these overuse injuries (46%), while medial plica syndrome (15%), biceps femoris tendinopathy (7.5%), patellar tendinopathy (9.4%), infrapatellar plica friction syndrome (7.5%), infrapatellar fat pad impingement (5.7%) and iliotibial band syndrome (3.7%) were other causes of knee pain in these athletes. In contrast to current belief, our results show that instead of patellofemoral cartilage overload, friction related overuse injuries are the most frequent and underestimated cause of knee pain in high level cyclists.

Traumatic injury of the knee extensor mechanism in skeletally immature patients: Outcome and classification.

BACKGROUND: The literature is limited on the etiology and outcome of acute traumatic knee extensor mechanism injuries in skeletally immature patients with lack of a reliable classification system. METHODS: Data on patients who sustained an acute traumatic injury of the knee extensor mechanism were reviewed with a minimum of 12-month follow-up. Functional outcome was evaluated regarding knee active range of motion. Functional outcome was described using the Knee Society Score (KSS). Data were expressed as mean ±â€¯standard deviation. RESULTS: Seventy-two patients with 74 knee extensor mechanism injuries were identified. The age at the time of injury was 13.9 ±â€¯1.9 years. They included 59 injuries with tibial tubercle avulsion fracture, six injuries with patellar tendon avulsion without bone injury, six injuries with combined patellar tendon avulsion with tibial tubercle fracture, two injuries with sleeve fracture, and one injury with quadriceps tendon avulsion. According to our classification, type IB1 injury was the commonest injury (79.7%). The time to return to sports was 5.23 ±â€¯2.98 months. The flexion was 128.7°â€¯±â€¯13.3°. A mean terminal extension lag of 5.6° was detected in three patients (4.1%). The KSS was 94.8 ±â€¯8.1 and the functional outcome was graded excellent in 64 patients (88.9%), good in seven patients (9.7%), and fair in one patient (1.4%). CONCLUSIONS: Traumatic injuries of the knee extensor mechanism in skeletally immature patients represent a wide variety of injuries including bony injuries in 82.4% of cases reviewed, tendinous injuries in 9.5%, and both bone and tendinous injuries in 8.1%. Our proposed classification system provides a more precise description of the injury pattern.

Subchondral insufficiency fracture of the knee: grading, risk factors, and outcome.

OBJECTIVE: To propose an magnetic resonance imaging (MRI) grading system for subchondral insufficiency fracture of the knee (SIFK) to predict outcome and assess risk factors. MATERIALS AND METHODS: A total of 50 SIFK patients were retrospectively reviewed utilizing two MRI examinations approximately a year apart and compared them with 51 control subjects. A grading system was introduced that classifies lesions as low- vs high-grade. Lesion location 3D dimensions, extent of bone marrow edema (BME), location of meniscal tears and associated extrusion, degree of chondrosis and among other parameters were stratified according to lesion grade and compared with follow-up examinations. Statistical analyses were performed (Pearson's correlation, binary logistic regression, and Chi-squared analysis). RESULTS: The majority of SIFK lesions were low-grade (LG; 78%) and most of them (70%) were observed in the medial femoral condyle. Predictor variables comparing low-grade and high-grade SIFK lesions included meniscal tear (p = 0.01), degree of extrusion (p < 0.003), chondrosis (p = 0.01), medial chondrosis grade (p = 0.001), medial femoral condyle (p = 0.01), surface collapse (p < 0.0001), marrow edema improvement (p < 0.0001), first MRI anteroposterior dimension (p = 0.001), transverse dimension (p < 0.001), and ellipsoid volume (p = 0.02). Predictor variables found to be significantly different between controls and patients were meniscal tear (p = 0.024), location of the medial meniscal tear (p < 0.0001), degree of extrusion (p < 0.0001), chondrosis (p < 0.0001), joint effusion (p < 0.0001), Baker's cyst (p < 0.0001), knee lock (p = 0.03) and buckle (p = 0.01), and history of trauma (p = 0.01). CONCLUSION: A SIFK grading system for MRI is introduced. Surrogate markers of high-grade lesions include medial meniscus posterior root tears with associated moderate to severe extrusion, high-grade chondrosis, larger lesion sizes (anteroposterior/transverse), and articular surface collapse. Improvement of BME on follow-up was highly predictive of low-grade disease.

The International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine classification of knee meniscus tears: three-dimensional MRI and arthroscopy correlation.

OBJECTIVES: To introduce MRI-based International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) classification system of meniscal tears and correlate it to the surgical findings from arthroscopy. We hypothesized that the ISAKOS classification will provide good inter-modality and inter-rater reliability for use in the routine clinical practice of radiologists and orthopedic surgeons. METHODS: In this HIPAA-compliant cross-sectional study, there were 44 meniscus tears in 39 patients (26 males, 16 females). Consecutive arthroscopy-proven meniscal tears (March 2017 to December 2017) were evaluated by two board-certified musculoskeletal radiologists using isotropic three-dimensional (3D) MRI user-defined reconstructions. The surgically validated ISAKOS classification of meniscal tears was used to describe medial meniscus (MM) and lateral meniscus (LM) tears. Prevalence-adjusted bias-adjusted kappa (PABAK) and conventional kappa, and paired t test and intra-class correlation coefficient (ICC) were calculated for categorical and numerical variables, respectively. RESULTS: For the MM, the PABAK for location, depth, length (ICC), pattern, quality of meniscus tissue, and zone was 0.7-1, 0.65, 0.57, 0.67, 0.78, and 0.39-0.7, respectively. For the LM, the PABAK for location, depth, length (ICC), pattern, quality of meniscus tissue, zone, and central to popliteus hiatus was 0.57-0.95, 0.57, 0.74, 0.93, 0.38, 0.52-0.67, and 0.48, respectively. The mean tear lengths were larger on MRI than on arthroscopy (mean difference MM 9.74 mm (6.66 mm, 12.81 mm; p < 0.001), mean difference LM 4.04 mm (0.31 mm, 7.76 mm; p = 0.034)). CONCLUSIONS: The ISAKOS classification of meniscal tears on 3D MRI provides mostly moderate agreement, which was similar to the agreement at arthroscopy. KEY POINTS: • There is a fair to good inter-method correlation in most categories of ISAKOS meniscus tear classification. • The tear lengths are significantly larger on MRI than on arthroscopy. • The inter-reader correlation on 3D MRI is moderate to excellent, with the exception of lateral meniscus tear patterns.

The term "floating" used in traumatic orthopedics.

BACKGROUND: The term "floating" is used in orthopedic literature to describe certain patterns of skeletal injuries that share one common character which is disruption and discontinuity of bones above and below a joint. The first time used in orthopedic literature being in late 1970 to describe a type of elbow injury. Later the word was used increasingly and applied to a variety of injuries affecting the knee, shoulder, hip, forearm, hand, and ankle. Currently, there are about 12 different skeletal injuries described as floating. OBJECTIVES: The aim of this article was to define the term "floating" used in traumatic orthopedics and to discuss its history, mechanism of injury in each region, treatment and outcomes based on the currently available literature. As there were many separate articles describing different sites of floating injuries, this review aimed to summarize all floating injuries into 1 article.

Establishment of Classification of Tibial Plateau Fracture Associated with Proximal Fibular Fracture.

OBJECTIVE: The purpose of this retrospective study was to determine the incidence of fibular fractures as an associated injury in tibial plateau fractures according to CT scan. We also attempt to introduce a new morphological sub-classification on this associated injury and to analyze the correlation between this classification and tibial plateau fractures. METHODS: We selected cases with fibular fractures from all the tibial plateau fracture patients. The cases were further divided into 2 groups: unicondylar group and bicondylar group. On the basis of our new classification system of fibular fracture, all the included cases were divided into 5 subgroups. RESULTS: Finally, a total of 150 cases associated with fibular fractures in 502 tibial plateau fracture cases were identified from our institution database. The incidence of fibular head fracture in tibial plateau fractures was 29.88% (150/502). Seventy-one cases (47.3%) were involved one condyle, and 79 cases (52.7%) involved both. It shows significant difference in the subgroup of avulsion fracture with horizontal fracture line (Type A) which is ratio of 16.9% in unicondylar group and 1.27% in bicondylar group. CONCLUSION: A new classification of this associated injury describing the morphology of the fracture fragments may improve operative planning.

Knee Cell-Based Cartilage Restoration.

As our patients become more physically active at all ages, the incidence of injuries to articular cartilage is increasing causing significant pain and disability. The intrinsic healing response of articular cartilage is poor because of its limited vascular supply and capacity for chondrocyte division. Nonsurgical management for the focal cartilage lesion is successful in the majority of patients. Those patients who fail conservative management may be candidates for a cartilage reparative or reconstructive procedure. The type of treatment available depends on a multitude of lesion-specific and patient-specific variables. First-line therapies for isolated cartilage lesions have demonstrated good clinical results in the correct patient, but typically repair cartilage with fibrocartilage, which has inferior stiffness, inferior resilience, and poorer wear characteristics. Advances in cell-based cartilage restoration have provided the surgeon a means to address focal cartilage lesions utilizing mesenchymal stem cells, chondrocytes, and biomimetic scaffolds to restore hyaline cartilage.

Rigidez en cirugía de reconstrucción del ligamento cruzado anterior / Knee stiffness in anterior cruciate ligament reconstruction

La rigidez de rodilla en cirugía de Reconstrucción del Ligamento Cruzado Anterior (R-LCA) es una complicación devastadora, alcanzando una incidencia variable entre el 4% y el 38%. La definición de artrofibrosis es aún poco clara, lo que ha llevado a distintos esquemas terapéuticos. Conocer la etiopatogenia es clave para entender los procesos y las posibles alternativas de tratamiento. Distintas clasificaciones han sido descritas, siendo la de Shelbourne la más usada, debido a su valor pronóstico asociado. El objetivo del tratamiento en una rodilla estable es mejorar la movilidad articular, la satisfacción del paciente, y disminuir el riesgo de artrosis a largo plazo. El tratamiento se puede dividir en quirúrgico y conservador. Ese último, se enfoca principalmente en buscar la causa y lograr una prevención e intervención temprana, siendo el manejo que con mayor frecuencia se realiza. El tratamiento quirúrgico es una opción cuando el tratamiento conservador falla. Se realizó una revisión de la literatura y de 150 pacientes sometidos a R-LCA, de los cuales 4 presentaron artrofibrosis a un seguimiento de 2 años. Además, presentamos nuestro algoritmo de manejo terapéutico.

Knee stiffness in Anterior Cruciate Ligament Reconstruction (ACL-R) is a devastating complication, with a variable incidence of 4% to 38%. The definition of arthrofibrosis is still unclear, which has led to different therapeutic schemes. Knowing the etiopathogenesis is key to understanding the processes and possible treatment alternatives. Different classifications have been described, with Shelbourne being the most used, due to its associated prognostic value. The aim of treatment in a stable knee is to improve joint mobility, patient satisfaction, and decrease the risk of long-term osteoarthritis. The treatment can be divided into operative and non-operative. The latter focuses mainly on finding the cause and achieving prevention and early intervention, being the management that is most frequently performed. Surgical treatment is an option when conservative treatment fails. A review of the literature and of 150 patients undergoing R-LCA was performed, of which 4 presented arthrofibrosis at a 2-year follow-up. In addition, we present our therapeutic management algorithm.

Distal Femoral Physeal Fractures.

Physeal fractures of the distal femoral are rare injuries accounting for less than 2% of all physeal injuries, and tend to have a worse prognosis than similar injuries in other locations. This article reviews the evaluation (including imaging), classification, and treatment of these injuries, and discusses their most important complications and their management, including vascular injury and growth arrest.

[Debridement in Focal Cartilage Damage of the knee. Systematical review of the literature and recommendations of the working group "clinical tissue regeneration" of the German Society of Orthopaedics and Trauma (DGOU)]. / Stellenwert des Débridements bei der Behandlung fokaler (Grad II ­â€ŠIII) Knorpelschäden des Kniegelenks. Systematische Literaturübersicht und Empfehlungen der AG Geweberegeneration (DGOU).

BACKGROUND: In clinical practice, there is still no definite treatment algorithm for focal, partial thickness cartilage lesions (grade II - III). It is well-established that debridement (shaving/lavage) of large degenerative cartilage lesions is not recommended, but there is no such recommendation in the case of focal, partial thickness cartilage defects. MATERIALS AND METHODS: The scientific rationale of cartilage shaving and joint lavage was investigated and a systematic analysis was performed of the literature on the clinical effect of cartilage debridement. Furthermore, a consensus statement on this issue was developed by the working group on Clinical Tissue Regeneration of the German Society of Orthopaedics and Trauma (DGOU). RESULTS: The therapeutic approach is different for asymptomatic lesions with biomechanical stable residual cartilage tissue and clinically symptomatic defects with unstable fragments. The benefit of a joint lavage or surface smoothening of focal partial thickness has not been proved. Even more importantly, the mechanical or thermal resection of cartilage tissue even induces a zone of necrosis in adjacent cartilage, and thus leads to additional injury. Therefore, large scale smoothening (shaving) of clinically asymptomatic, fibrillated or irregular cartilage defects should not be performed. However, if there are clinical symptoms, resection of unstable and delaminated cartilage fragments may be reasonable, as it can reduce harmful shear tension in residual tissue. This can help to brake the progression of the damage and avoid formation of free bodies. CONCLUSION: The decision criteria for debridement of partial thickness focal cartilage lesions are multifactorial and include the clinical symptoms, the size and the degree of the defect, the stability of remaining cartilage, localisation of the defect, and individual patient-specific parameters. Debridement is not recommended for asymptomatic lesions, but may be reasonable for symptomatic cases with unstable tissue.

Knee Pain and Mobility Impairments: Meniscal and Articular Cartilage Lesions Revision 2018: Using the Evidence to Guide Physical Therapist Practice.

Meniscus and articular cartilage lesions are common knee injuries. The resulting knee pain and mobility impairments can be improved by physical therapists during nonoperative and operative management. Recommendations from clinical practice guidelines (CPGs) such as this revision, titled "Knee Pain and Mobility Impairments: Meniscal and Articular Cartilage Lesions," published in the February 2018 issue of JOSPT, can help physical therapists engage in evidence-informed practice and reduce unnecessary clinical variation. J Orthop Sports Phys Ther 2018;48(2):123-124. doi:10.2519/jospt.2018.0503.

Extensor Mechanism Injury in the Pediatric Population-A Clinical Review.

The extensor mechanism of the knee-consisting of the four muscles of the quadriceps, the quadriceps tendon, the patella, and the patellar ligament-is essential for lower extremity function during both standing and ambulation. The presence of articular cartilage and growing physes in the pediatric knee, coupled with the generation of significant tensile force, creates an opportunity for pathology unique to the pediatric population.Tibial tubercle fractures and patella injuries are quite rare, and even pediatric-trained orthopaedic surgeons may not be exposed to these injuries on a regular basis. It is the intent of this article to discuss the current literature regarding the mechanism of injury, diagnostic workup, classification, indications for surgical versus non-surgical management, and techniques for operative management for both tibial tubercle and patella (transverse and sleeve) fractures.

Symptomatic Focal Knee Chondral Injuries in National Football League Combine Players Are Associated With Poorer Performance and Less Volume of Play.

PURPOSE: To (1) describe the magnetic resonance imaging (MRI) characteristics of knee chondral injuries identified at the National Football League (NFL) Combine and (2) assess in-game performance of prospective NFL players with previously untreated knee chondral injuries and compare it with matched controls. METHODS: All players with knee chondral injuries identified at the NFL Combine (2009-2015) were retrospectively reviewed. Players with prior knee surgery were excluded. A knee MRI for each player was reviewed; location, modified International Cartilage Repair Society (ICRS) grade (I-IV), and associated compartment subchondral edema were documented. Position, respective NFL Draft pick selection number, games started, played, snap percentage, and position-specific performance metrics during the first 2 NFL seasons were recorded for the injury and injury-free control group composed of players with (1) no prior knee injury, (2) no significant missed time prior to the NFL (≤2 total missed games in college), (3) no history of knee surgery, and (4) drafted in the respective NFL Draft following the NFL Combine. RESULTS: Of the 2,285 players reviewed, 101 (4.4%) had an injury without prior knee surgery. The patella (63.4%) and trochlea (34%) were most commonly affected. Defensive linemen were at highest risk for unrecognized injuries (odds ratio 1.8, P = .015). Players with previously untreated injuries, compared with controls, were picked later (mean pick: 125.8) and played (mean: 23) and started (mean: 10.4) fewer games during the initial 2 NFL seasons (P < .001 for all). Particularly, subchondral bone edema and full-thickness cartilage injuries were associated with fewer games played (P = .003). CONCLUSIONS: The patellofemoral joint was most commonly affected in NFL Combine participants. Previously untreated knee articular injuries in players at the NFL Combine are associated with poorer early NFL performance in comparison to uninjured players. Subchondral bone edema and full-thickness cartilage injury on MRI were associated with fewer games played during the initial NFL career. LEVEL OF EVIDENCE: Level III, case-control study.