and the Center for Musculoskeletal Surgery (S.S.), Charit-Universittsmedizin Berlin, Campus Charit Mitte, Charitplatz 1, 10117 Berlin, Germany. Conclusion: 11, Clinics in Sports Medicine, Vol. 4, Arthroscopy: The Journal of Arthroscopic & Related Surgery, Vol. 3. To enhance certain organs and structures that otherwise are . 07, The American Journal of Sports Medicine, Vol. 12, No. Spontaneous Osteonecrosis of the Knee (SONK), Osgood Schlatter's Disease (Tibial Tubercle Apophysitis), Anterior Superior Iliac Spine (ASIS) Avulsion, Anterior Inferior Iliac Spine Avulsion (AIIS), Concussions (Mild Traumatic Brain Injury). Please enable it to take advantage of the complete set of features! 193, No. Bethesda, MD 20894, Web Policies A 22-year-old female sustained a lateral patellar dislocation while playing intramural soccer. ( c) 3D reconstruction of CT scan for visualization of trochlear dysplasia. The aim of the surgery is to repair the knee damage caused by patellar dislocation and to correct the primary anatomical anomaly. Anterior tibial translocation, when measured at the midsagittal plane of the lateral femoral condyle with regard to a plane parallel to the cephalocaudal axis of the image, was a relatively specific indicator of ACL disruption. You recommend reconstruction of her medial patellofemoral ligament (MPFL) given her recurrent instability. ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. 22-year-old female with multiple previous dislocations, the MRI findings in Figure A, and a tibial tubercle-trochlear groove (TT-TG) distance of 26 mm, 22-year-old female with the MRI findings in Figure B and a TT-TG distance of 18 mm, 13-year-old female with no prior history of knee injury and the MRI findings in Figure A, 13-year-old female with no prior history of knee injury and the MRI findings in Figure B, 13-year-old female with multiple previous dislocations despite PT and the MRI findings in Figure A. Which of the following is the most likely site of injury seen on MRI? (OBQ19.184) 1, Pilot and Feasibility Studies, Vol. Additionally, complex injuries to bone, cartilage, and ligaments may occur. Tanaka MJ, Elias JJ, Williams AA, Demehri S, Cosgarea AJ. MeSH In healthy individuals . The typical injury pattern is a tear of the medial patellofemoral ligament (MPFL) and bone bruises of the patella and the lateral femoral condyle. 28, No. 20 Acutely, osteochondral and chondral fractures of the medial facet of the patella and/or the lateral femoral condyle can be a common finding on radiographs, MRI, ultrasound, arthroscopy, and open procedures (). Log-in above or renew your membership today. Which of the following factors is associated with the highest risk of persistent patellar instability? MIKE MAH, MD, FRCPC. 4, Korean Journal of Radiology, Vol. Courtesy of Daniel Bodor, MD, Radsource. 2004;32(5):1114-21. Clin Sports Med. (OBQ07.112) 1, Chinese Journal of Traumatology, Vol. . Reference article, Radiopaedia.org (Accessed on 11 Dec 2022) https://doi.org/10.53347/rID-16281, {"containerId":"expandableQuestionsContainer","displayRelatedArticles":true,"displayNextQuestion":true,"displaySkipQuestion":true,"articleId":16281,"questionManager":null,"mcqUrl":"https://radiopaedia.org/articles/patellofemoral-instability/questions/1618?lang=us"}. Surgical replacement of the knee, also called total knee arthroplasty (TKA), is one of the most successful and cost-effective interventions in modern medicine [], but TKA is not without risk or complication.As a major surgical procedure typically performed on older patients, who often have comorbid conditions, TKA is subject to both immediate and delayed complications and failures. 22, No. A Systematised MRI Approach to Evaluating the Patellofemoral Joint. Dejour H, Walch G, Neyret P, Adeleine P. [Dysplasia of the Femoral Trochlea]. 236, No. Draw a line along the posterior femoral condyles, and then draw the following lines perpendicular to this line: The distance has been shown to be slightly less when measured on MRI than CT 1. The most common procedures, in addition to MPFL reconstruction, include trochleoplasty, medialization of the tibial tuberosity, and medial capsular plication. The site is secure. 32, No. Purpose: The measurements are used to quantify patellar instability. 12, Canadian Association of Radiologists Journal, Vol. 2. Neither dMPT nor dPT was correlated with height, BMI, or patellar diameter. 24, No. 4. Prevalence is 6-77 per 100,000 population 2. 3, The American Journal of Sports Medicine, Vol. 87, No. The https:// ensures that you are connecting to the 2, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. 2, American Journal of Roentgenology, Vol. Measurement Superimpose axial images of: femoral condyles 3, Revista Brasileira de Ortopedia, Vol. 9, Orthopaedic Journal of Sports Medicine, Vol. 2, International Orthopaedics, Vol. 98, No. 38, No. Surgical modalities are: The knee is a complex synovial joint that can be affected by a range of pathologies: ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. 44, No. 9, No. Methods: 1From the Department of Radiology (G.D., A.S.I.) A 27-year-old football player sustains an acute lateral patellar dislocation. Intercondylar distance correlated weakly with dPT (r = -.241; P = .041). 1, 13 November 2018 | RadioGraphics, Vol. 2013;41(1):51-7. Average patella diameter was 37.9 2.7 (95% CI 37.1-38.7) mm in women and 42.4 3.2 (95% CI 41.5-43.3) mm in men. The above video demonstrates the mechanism of injury in patellar dislocation. 32, No. Enter your email address below and we will send you your username, If the address matches an existing account you will receive an email with instructions to retrieve your username. 3, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. Which of the following structures attaches between the medial epicondyle and adductor tubercle of the femur? Technique guides are not considered high yield topics for orthopaedic standardized exams including ABOS, EBOT and RC. Knee Surg Sports Traumatol Arthrosc. Patellofemoral instability or maltracking is the clinical syndrome due to morphologic abnormalities in the patellofemoral joint where the patella is prone to recurrent lateral dislocation. Epub 2016 Jun 29. Patellofemoral Pain in Adolescents: Understanding Patellofemoral Morphology and Its Relationship to Maltracking. 1, 11 October 2016 | RadioGraphics, Vol. Skeletal Radiol. Are the Osseous and Tendinous-Cartilaginous Tibial Tuberosity-Trochlear Groove Distances the Same on CT and MRI? 4, Medicinos teorija ir praktika, Vol. 26, No. 37, No. 52, No. In the acute and subacute setting MRI displays features of lateral patellar dislocation as: knee joint effusion medial patellofemoral ligament tear bone contusions or cartilage injuries of the medial patella facet and lateral femoral condyle edema/hemorrhage of vastus medialis muscle intra-articular fragments 7-8, The Egyptian Journal of Radiology and Nuclear Medicine, Vol. 2018 Dec;476(12):2334-2343. doi: 10.1097/CORR.0000000000000499. Level II, diagnostic study. 26, No. Characterization of patellar maltracking using dynamic kinematic CT imaging in patients with patellar instability. 21, No. Imaging findings Prior to reduction, the patient had one-view imaging of the right knee. Radiology 1993;188(3):661-667. Am J Sports Med. A short presentation on the practical issues related to the patellofemoral joint (subluxation, dislocation and incongruence) and chondromalacia Bhavin Jankharia Follow Doctor Advertisement Recommended Patella dislocations Dr Gandhi Kota Patello femoral jt. Frings J, Dust T, Krause M, Ohlmeier M, Frosch KH, Adam G, Warncke M, Maas KJ, Henes FO. Acute patellar dislocation accounts for 2% to 3% of all knee injuries 1 and is the second most common cause of traumatic knee hemarthrosis. 9, Clinics in Sports Medicine, Vol. 50, No. 203, No. 41, No. Treatment is nonoperative with bracing for first time dislocation without bony avulsion or presence of articular loose bodies. Mean height was 170.1 7.7 cm in women and 181.8 6.4 cm in men. The intersection of a line extended from the middle of the shaft and Blumensaat's line, Anterior to a line extended from the middle of the shaft and Blumensaat's line, Posterior to a line extended from the posterior cortex of the shaft and distal to Blumensaat's line, Anterior to a line extended from the posterior cortex of the shaft and distal to Blumensaat's line, Anterior to a line extended from the posterior cortex of the shaft and proximal to Blumensaat's line. 5 Athleticum, University Medical Center Hamburg-Eppendorf, . Dynamic mediolateral patellar translation (dMPT) and dynamic patellar tilt (dPT) were measured on two occasions by two independent examiners. 2010;30(4):961-81. 50, No. Magnetic resonance (MR) imaging is reliable in identifying risk factors for chronic patellar instability and in assessing knee joint damage associated with patellar dislocation. lateralization of the tibial tuberosity: femorotibial malrotation, abnormal muscle tone, vastus medialis atrophy, ligament or retinaculum injury or laxity (, edema/hemorrhage of vastus medialis muscle, medial patellofemoral ligament reconstruction. 4, Singapore Medical Journal, Vol. Giovannetti de Sanctis E, Mesnard G, Dejour D. Trochlear Dysplasia: When and How to Correct. and transmitted securely. 2, Trauma und Berufskrankheit, Vol. 09, The Journal of Knee Surgery, Vol. 12, Journal de Radiologie Diagnostique et Interventionnelle, Vol. 49, No. Patella alta: association with patellofemoral alignment and changes in contact area during weight-bearing, Reliability and interobserver variability in radiological patellar height ratios, Patellar height measurement in trochlear dysplasia, MR imaging of Baker cysts: association with internal derangement, effusion, and degenerative arthropathy, The patellotrochlear index: a new index for assessing patellar height, Radiographic and computed tomographic analysis of the position of the tibial tubercle in recurrent dislocation and subluxation of the patella, The tibial tuberosity-trochlear groove distance: a comparative study between CT and MRI scanning, Femoral avulsion of the medial patellofemoral ligament after primary traumatic patellar dislocation predicts subsequent instability in men: a mean 7-year nonoperative follow-up study, The abnormal lateral patellofemoral angle: a diagnostic roentgenographic sign of recurrent patellar subluxation, Arthroscopic treatment of acute patellar dislocations, Fat-suppressed three-dimensional spoiled gradient-echo MR imaging of hyaline cartilage defects in the knee: comparison with standard MR imaging and arthroscopy, Accuracy of fat-suppressed three-dimensional spoiled gradient-echo FLASH MR imaging in the detection of patellofemoral articular cartilage abnormalities, MRI of patellar articular cartilage: evaluation of an optimized gradient echo sequence (3D-DESS), Clinical magnetic resonance imaging of articular cartilage, Imaging of patellar cartilage with a 2D multiple-echo data image combination sequence, Medial patellar ossification after patellar instability: a radiographic finding indicative of prior patella subluxation/dislocation, Medial retinacular complex injury in acute patellar dislocation: MR findings and surgical implications, Knee effusion: normal distribution of fluid, Acute dislocation of the patella: a correlative pathoanatomic study, Current concepts of lateral patella dislocation, Isolated repair of the medial patellofemoral ligament in primary dislocation of the patella: a prospective randomized study, Arthroscopic surgery for primary traumatic patellar dislocation: a prospective, nonrandomized study comparing patients treated with and without acute arthroscopic stabilization with a median 7-year follow-up, Arthroscopic medial retinacular repair after patellar dislocation with and without underlying trochlear dysplasia: a preliminary report, Fully arthroscopic stabilization of the patella, Effects of lateral retinacular release on the lateral stability of the patella, A prospective evaluation of trochleoplasty for the treatment of patellofemoral dislocation and instability, Trochleaplasty for recurrent patellar dislocation in association with trochlear dysplasia: a 4- to 14-year follow-up study, CT changes after trochleoplasty for symptomatic trochlear dysplasia, Trochleaplasty for patellar instability due to trochlear dysplasia: a minimum 2-year clinical and radiological follow-up of 19 knees, Elmslie-Trillat procedure for the treatment of recurrent patellar instability, Tibial tuberosity transfer for episodic patellar dislocation, To read the full-text, please use one of the options below to sign in or purchase access, Purchase this article as pay-per-view (unlimited access for 24 hours), Layered Approach to the Anterior Knee: Normal Anatomy and Disorders Associated with Anterior Knee Pain, Imaging of Sports-related Injuries of the Lower Extremity in Pediatric Patients, Patelofemoralinio skausmo sindromo vaizdinimas. The typical MR imaging findings after patellar dislocation, the assessment of predisposing anatomic factors, and current surgical procedures are discussed and illustrated. 5, Sports Medicine and Arthroscopy Review, Vol. 2011;40(4):375-87. 7, HSS Journal: The Musculoskeletal Journal of Hospital for Special Surgery, Journal of Orthopaedic Surgery, Vol. Quadriceps and Patellar tendon Patellar dislocation Bone and Cartilage Normal and abnormal bone marrow Avascular Necrosis Insufficiency fracture Osteochondritis Dissecans Ligaments MR-signs of ligament tear Anterior Cruciate Ligament The ACL has interesting anatomy. Are the Osseous and Tendinous-Cartilaginous Tibial Tuberosity-Trochlear Groove Distances the Same on CT and MRI? Dickens A, Morrell N, Doering A, Tandberg D, Treme G. Tibial Tubercle-Trochlear Groove Distance: Defining Normal in a Pediatric Population. Development of Real-Time Kinematic Magnetic Resonance Imaging (kMRI) Techniques for Studying the Kinematics of the Spine and Joints in Dogs-Preliminary Study on Cadavers. 2021;50(7):1399-409. 4 Department of Radiology, The Johns Hopkins . Knee Surg Sports Traumatol Arthrosc. PMC Intra- and interrater reliability were excellent for dMPT and dPT. Published by Elsevier Inc. All rights reserved. Wolfe S, Varacallo M, Thomas JD, Carroll JJ, Kahwaji CI. Patients with pronounced ligamentous tears or large osteochondral lesions require prompt surgery. 2023 Bobby Menges Memorial HSS Limb Reconstruction Course, Medial Retinacular Plication (Modified Insall ), MPFL Reconstruction - Pediatric and Adolescent, Type in at least one full word to see suggestions list, Orthopaedic Summit Evolving Techniques 2021, Correcting Femoral Torsion & Version With A Femoral Osteotomy: Not So Hard, Let Me Share My Experience - Robert Buly, MD, MS, Commentary: Let My Experience Speak - David R. Diduch, MD, Pro: MPFL Reconstruction Nothing More, Keep It Simple, Safe & Effective - Jason Koh, MD, MBA, Patellar Dislocation with Loose Chondral Fragment and Medial Facet Fx, Patella dislocation with large loosebody in 25M. 23, No. 4, Orthopaedic Journal of Sports Medicine, Vol. anterior cruciate ligament avulsion fracture, posterior cruciate ligament avulsion fracture, Ahlback classification system in assessing osteoarthritis of the knee joint, Kellgren and Lawrence system for classification of osteoarthritis, anterior cruciate ligament mucoid degeneration, MRI grading system for meniscal signal intensity. HHS Vulnerability Disclosure, Help 10, Current Physical Medicine and Rehabilitation Reports, Vol. Primarily, CT is useful to assess the anterior tibial tubercle-trochlear groove distance, of which an abnormal measurement is an indication of patellar instability. 37, No. ( b) Left lower extremity CT showing a more severe rotational abnormality of the femur, with chronic patellar subluxation and trochlear dysplasia. She completed 6 weeks of physical therapy following her first dislocation. 2022 May;38(5):1581-1583. doi: 10.1016/j.arthro.2021.11.034. The Insall-Salvati ratio is classically measured to determine patellar height, and is measured on the lateral view with the knee flexed to 30 degrees; it is the ratio measuring the length of the patellar tendon (LL; from the inferior patellar pole to the tibial tubercle) and the patellar length (LP; the longest diagonal length of the patella). You see a patient in the emergency room with an acute lateral patellar dislocation. Disclaimer, National Library of Medicine 48, No. (OBQ08.49) One hundred knees of healthy individuals with no history of patellofemoral symptoms were scanned with dynamic MRI sequences, during repetitive cycles of flexion (40) and full extension. Link, Google Scholar; 12 Tung GA, Davis LM, Wiggins ME, Fadale PD. 10, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. Federal government websites often end in .gov or .mil. Clin Orthop Relat Res. 1, Korean Journal of Radiology, Vol. Where should your femoral tunnel be located when looking at Figure A? 5, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. 24, No. 27, No. Keywords: Most patients with patellar instability are young and active individuals, especially females in the second decade. 8, American Journal of Roentgenology, Vol. 3, RFo - Fortschritte auf dem Gebiet der Rntgenstrahlen und der bildgebenden Verfahren, Vol. Fithian D, Paxton E, Stone M et al. 206, No. Reference article, Radiopaedia.org (Accessed on 11 Dec 2022) https://doi.org/10.53347/rID-44662, {"containerId":"expandableQuestionsContainer","displayRelatedArticles":true,"displayNextQuestion":true,"displaySkipQuestion":true,"articleId":44662,"questionManager":null,"mcqUrl":"https://radiopaedia.org/articles/patellar-translation-tt-tg-distance/questions/2392?lang=us"}. (SAE08AN.85) This image shows a laterally displaced patella without apparent fracture ( Fig. The typical injury pattern is a tear of the medial patellofemoral ligament (MPFL) and bone bruises of the patella and the lateral femoral condyle. (OBQ10.188) 3, Magnetic Resonance Imaging Clinics of North America, Vol. Accessibility How is patellar subluxation diagnosed? If the address matches an existing account you will receive an email with instructions to reset your password. 25, No. 56, No. 8, Clinics in Sports Medicine, Vol. 2022 Oct 15;12(20):2790. doi: 10.3390/ani12202790. knee to knee collision in basketball, or football helmet to side of knee, between medial epicondyle and adductor tubercle, is primary restraint in first 20 degrees of knee flexion, patellar-femoral bony structures account for stability in deeper knee flexion, trochlear groove morphology, patella height, patellar tracking, May occur from a direct blow (ex. Am J Sports Med. Subscribe now (individual subscription: $237.00), (This functionality works only for purchases made as a guest), Knee Surgery, Sports Traumatology, Arthroscopy, European Journal of Orthopaedic Surgery & Traumatology, Vol. 26, No. This site needs JavaScript to work properly. 2, Journal of Orthopaedic Science, Vol. 41, No. 5,12,16,18,23,38,46,49,52,55,56,64,65,67,68 . All of the following are predisposing factors for lateral patellar dislocation in a native knee EXCEPT? Increased Patellar Volume/Width and Decreased Femoral Trochlear Width Are Associated With Adolescent Patellofemoral Pain. Midsubstance oblique retinacular ligament rupture, Soft-tissue avulsion of medial patellofemoral ligament, Midsubstance medial patellofemoral ligament rupture, Bony avulsion of medial patellofemoral ligament. 36, No. For comprehensive assessment of patellar dislocation, a radiologist should be able to identify typical injury patterns, know standard methods to assess risk factors for patellar instability, and be familiar with surgical options. 2016. This is her third dislocation in the last 6 months. J Bone Joint Surg Am. ( a) Right lower extremity CT showing a supratrochlear spur, patellar ossicle, and abnormal femoral rotation. 7, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. Patellar apprehension and mobility should be assessed by medial and lateral patellar translation. In: StatPearls [Internet]. 22, No. 3, The Physician and Sportsmedicine, Vol. . 27, No. 38, No. 22, No. The typical injury pattern is a tear of the medial patellofemoral ligament (MPFL) and bone bruises of the patella and the lateral femoral condyle. 40, No. 24, No. 24, No. sharing sensitive information, make sure youre on a federal 142, No. Unable to process the form. 2, Revista Brasileira de Ortopedia (English Edition), Vol. 04, Archives of Orthopaedic and Trauma Surgery, Vol. What is the most likely diagnosis? It is an intra-articular structure, but it is extra-synovial. To provide normal values for physiological patellofemoral tracking in a representative group of healthy individuals, as well as sex differences, using real-time 3T-magnetic resonance imaging (MRI) and to test for the reliability of the presented technique. 7, The American Journal of Sports Medicine, Vol. Copyright 2021 Arthroscopy Association of North America. Diederichs G, Khlitz T, Kornaropoulos E, Heller M, Vollnberg B, Scheffler S. Magnetic Resonance Imaging Analysis of Rotational Alignment in Patients with Patellar Dislocations. An official website of the United States government. 215, No. 3, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. 1, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. Clipboard, Search History, and several other advanced features are temporarily unavailable. Skeletal Radiol. 6, No. PRP is obtained from your blood by . 66.1 ). 1, Egyptian Journal of Radiology and Nuclear Medicine, Vol. 22, No. First-time patellar dislocation typically occurs with twisting knee motions, during which the medial ligamentous stabilizers rupture, and the patella strikes against the lateral femoral condyle. The "crossing sign"represents an abnormally elevated floor of the trochlear groove rising above the top of the wall of one of the femoral condyles, assessed on lateral radiographs. FOIA Sci Rep. 2020 Oct 8;10(1):16770. doi: 10.1038/s41598-020-72332-9. Link, Google Scholar 28, No. Chhabra A, Subhawong T, Carrino J. 9.9. 40, No. 2, American Journal of Roentgenology, Vol. Kamel S, Kanesa-Thasan R, Dave J et al. 2022;41(1):77-88. 2014;96(4):318-24. {"url":"/signup-modal-props.json?lang=us\u0026email="}, Brown N, Foster T, Elena B, et al. Which of the following best describes the radiographic landmarks on a lateral radiograph for locating the femoral attachment of the medial patellofemoral ligament (MPFL) during reconstruction? 1. Transient Patellar Dislocation - MSK Radiology Imaging Findings: Hyperintense marrow edema of the anterolateral femoral condyle consistent with bone contusion. 5, The American Journal of Sports Medicine, Vol. 215, No. Patellar translation can be measured using the tibial-tuberosity to trochlear groove distance (TT-TG distance) by calculating the transverse length between the trochlear groove on the femur and tibial tuberosity on axial images. Tibial tuberosity-trochlear groove (TT-TG) distance, bisecting the trochlear groove sulcus (TG), measure the distance between TT and TG = TT-TG distance. Measurement Superimpose axial images of: femoral condyles Common radiological parameters were measured using static MRI, and correlations were calculated. 2, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. 5, No. Which of the following is the most likely site of origin for the loose fragment? Patellar instability symptoms were correlated with maltracking severity. Unable to process the form. 2015;44(8):1085-93. Background: Tibial tubercle-trochlear groove distance (TT-TG) is a commonly used measurement for surgical decision making in patients with patellofemoral malalignment and instability. Canal S, Tamburro R, Falerno I, Signore FD, Simeoni F, De Pasquale F, De Bonis A, Maraone A, Paolini A, Bianchi A, Rosto M, Vignoli M. Animals (Basel). 14, No. The skyline view can show decreased trochlear depth and a large sulcus angle (>144). 3, Scandinavian Journal of Medicine & Science in Sports, Vol. 68, No. Dr. Jonathan Chung has joined X-Ray Associates, January, 2021. Results: Which radiographic measurement is used to indicate when a lateral retinacular release may be helpful? A Platelet-Rich Plasma (PRP) injection is a solution containing concentrated levels of platelets in plasma. Patients with primary patellar dislocation without severe internal derangement who lack major risk factors can be treated conservatively. The measurements are used to quantify patellar instability. 12, Topics in Magnetic Resonance Imaging, Vol. 4, No. S1, Sports Medicine and Arthroscopy Review, Vol. PURPOSE: To demonstrate the magnetic resonance (MR) imaging characteristics of patellar sleeve fracture, a cartilaginous avulsion from the lower pole of the patella occurring during forceful contraction of the quadriceps muscle against a partially flexed knee. 22, No. 1, American Journal of Roentgenology, Vol. 5, Indian Journal of Radiology and Imaging, Vol. Radiographics. Patellofemoral instability. Hinckel B, Gobbi R, Filho E et al. Patellar Instability Radiology Radiographs: Radiographs are necessary to identify fracture, loose bodies, arthritis, malalignment and abnormal anatomy. Subluxation of 5 mm or more had 58% sensitivity, 93% specificity, and 69% accuracy for an ACL tear. 1, Evidence-Based Complementary and Alternative Medicine, Vol. During the range of motion, mean dMPT was 1.7 2.4 (95% CI .9-2.5) mm in females and 1.8 2.7 (95% CI 1.1-2.6) mm in males (P = .766). 45, No. lateral patellar motion, with one, two, and three quadrants corresponding to 75-99, 100-125, and >125 %, respectively. 48, No. He is a graduate of the University of Toronto - Hon Bsc (physics) 1977 and MD 1981. There is also a bone contusion of the inferomedial patella. A high school softball player has chronic activity-related anterior knee pain without a history of instability. 97, No. 10, American Journal of Roentgenology, Vol. Patellar instability might display the following different clinical presentations 3: The normal patellofemoral joint has two kinds of stabilizers - active stabilizers (extensor muscles) and passive stabilizers (bones and ligaments): Three major morphologic abnormalities that predispose to patellar instability: Other factors contributing to patellar instability include 3,4: The most common mechanism of first-time patellar dislocation is internal rotation of the femur relative to the knee (i.e. Skeletal Radiol. 8. 9, No. (OBQ11.188) Level of evidence: Dynamic mediolateral patellar translation is a size- and sex-independent parameter for proximal patellar tracking. 2002; 225:736-743. doi . The .gov means its official. 22, No. 5. In addition, surgical correction of anatomic variants will help reduce the potential for chronic instability. had normal tracking patterns; 41 (82 %) had increased lateral translation in extension, which we . 1. Would you like email updates of new search results? Rev Chir Orthop Reparatrice Appar Mot. 2022 Radiological Society of North America, Epidemiology and natural history of acute patellar dislocation, Incidence and risk factors of acute traumatic primary patellar dislocation, Acute patellar dislocations: the natural history, Characteristics of patients with primary acute lateral patellar dislocation and their recovery within the first 6 months of injury, Acute lateral patellar dislocation at MR imaging: injury patterns of medial patellar soft-tissue restraints and osteochondral injuries of the inferomedial patella, Medial patellofemoral ligament injury patterns and associated pathology in lateral patella dislocation: an MRI study, Transient lateral patellar dislocation: diagnosis with MR imaging, Prior lateral patellar dislocation: MR imaging findings, Correlation of MR imaging findings and open exploration of medial patellofemoral ligament injuries in acute patellar dislocations, MRI of osteochondral defects of the lateral femoral condyle: incidence and pattern of injury after transient lateral dislocation of the patella, Acute dislocation of the patella: MR findings, Patellar instability: assessment on MR images by measuring the lateral trochlear inclinationinitial experience, Objective patellar instability: MR-based quantitative assessment of potentially associated anatomical features, Patellar height on sagittal MR imaging of the knee, Imaging the femoral sulcus with ultrasound, CT, and MRI: reliability and generalizability in patients with patellar instability, The supporting structures and layers on the medial side of the knee: an anatomical analysis, Factors of patellar instability: an anatomic radiographic study, Dysplasia of the femoral trochlea [in French], Minimal rotation aberrations cause radiographic misdiagnosis of trochlear dysplasia, Comparison of native axial radiographs with axial MR imaging for determination of the trochlear morphology in patients with trochlear dysplasia. 2, International Orthopaedics, Vol. 33, No. The definition of maltracking refers to the dynamic malpositioning of the patella within the trochlear groove that occurs during active range of motion of the knee. tight ITB and vastus lateralis), acute dislocation usually associated with a large hemarthrosis, absence of swelling supports ligamentous laxity and habitual dislocation mechanism, measured in quadrants of translation (midline of patella is considered "0"), and also should be compared to contralateral side, normal motion is <2 quadrants of patellar translation, lateral translation of medial border of patella to lateral edge of trochlear groove is considered "2" quadrants and is considered abnormal amount of translation, passive lateral translation results in guarding and a sense of apprehension, excessive lateral translation in extension which "pops" into groove as the patella engages the trochlea early in flexion, trochlear groove lies in same plane as anterior border of lateral condyle, anterior border of lateral condyle lies anterior to anterior border of medial condyle, represents convex trochlear groove/hypoplastic medial condyle, Blumensaat's line should extend to inferior pole of the patella at 30 degrees of knee flexion, angle between line along subchondral bone of lateral trochlear facet + posterior femoral condyles, values > 140 degrees indicate flattening of the trochlea concerning for dysplasia, measures the distance between 2 perpendicular lines from the posterior cortex to the tibial tubercle and the trochlear groove, help further rule out suspected loose bodies, osteochondral lesion and/or bone bruising, tear usually at medial femoral epicondyle, NSAIDS, activity modification, and physical therapy, mainstay of treatment for first time patellar dislocator, without any loose bodies or intraarticular damage, short-term immobilization for comfort followed by 6 weeks of controlled motion, closed chain short arc quadriceps exercises, core and hip strengthening to improve limb positioning and balance (hip abductors, gluteals, and abdominals), displaced osteochondral fractures or loose bodies, may be an indication for operative treatment in a first-time dislocator, arthroscopic vs open removal versus repair of the osteochondral fragment, primary repair with screws or pins if sufficient bone available for fixation, first time dislocation with bony fragment, direct repair when surgery can be done within first few days, no clinical studies support this over nonoperative treatment, MPFL reconstruction with autograft vs allograft, gracilis or semitendinosus commonly used (stronger than native MPFL), femoral origin can be reliably found radiographically (Schottle point), a femoral tunnel positoined too proximally results in graft that is too tight ("high and tight"), severe trochlear dysplasia is the most important predictor of residual patellofemoral instability after isolated MPFL reconstruction, Fulkerson-type osteotomy (anterior and med, may be used in addition to MPFL or in isolation for significant malalignment, anteromedialized displacement of osteotomy and fixation, correct TT-TG to 10-15mm (never less than 10mm), distal displacement of osteotomy and fixation, isolated release no longer indicated for instability, only indicated if there is excessive lateral tilt or tightness after medialization, rarely addressed (in the USA) even if trochlear dysplasia present, arthroscopic or open trochlear deepening procedure, do not do tibial tubercle osteotomy (will harm growth plate of proximal tibia), redislocation rates with nonoperative treatment may be high (15-50%) at 2-5 years, recurrence rate is highest in those patients who sustain a primary dislocation, almost exclusively iatrogenic as a result of prior patellar stabilization surgery. 97, No. Abstract. Radiology 1994;193(3):829-834. Chronic patellar instability, if not treated, may lead to severe arthritis and chondromalacia patellae. Editorial Commentary: Real-Time Dynamic Magnetic Resonance Imaging of the Patellofemoral Joint: Ready for Prime Time? 2. 11, European Journal of Radiology Open, Vol. 20, No. "Double contour sign" is a double line at the anterior aspect of condyles and is seen if the medial condyle is hypoplastic. 1, Orthopaedic Journal of Sports Medicine, Vol. 7. 205, No. A patient presents to your sports medicine clinic with knee pain and swelling. 15, No. 213, No. 6, International Journal of Environmental Research and Public Health, Vol. 3, Operative Techniques in Sports Medicine, Vol. 21, No. 9, No. 2, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. 2022, The American Journal of Sports Medicine, Vol. 2016 Nov;24(11):3634-3641. doi: 10.1007/s00167-016-4216-9. 1. 44, No. 38, No. 3, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. X-rays may be used to. Before 4, Journal of Medical Imaging and Radiation Sciences, Vol. 41, No. helmet to knee collision in football), Pathology is usually proximal (e.g. ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. Prevalence of Lateral Patellofemoral Maltracking and Associated Complications in Patients with Osgood Schlatter Disease. 2016;8(1):45-8. The measurements are used to quantify patellar instability. Figure 49 shows an acute axial MRI scan of a right knee. 4, BMC Musculoskeletal Disorders, Vol. Normal dPT showed a dependency on sex and was 1.3 2.9 (.4-2.1) in women and -0.2 3.8 (-1.2-0.9) in men. Radiology. Epub 2019 Dec 13. 4 Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. Patellar tendon length: the factor in patellar instability? 25, No. Is Superolateral Hoffa Fat Pad Edema a Consequence of Impingement between Lateral Femoral Condyle and Patellar Ligament? Skeletal Radiol. 2, Journal of Computer Assisted Tomography, Vol. An athlete sustains a traumatic patellar dislocation. 11, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. Recurrent patellar dislocations usually occur in individuals with anatomic variants of the patellar stabilizers, such as trochlear dysplasia, patella alta, and lateralization of the tibial tuberosity. 5, Journal of Orthopaedic Science, Vol. To diagnose a patellar subluxation, your doctor will bend and straighten the injured knee and feel the area around the kneecap. Copyright 2022 Lineage Medical, Inc. All rights reserved. Patellar instability is a condition characterized by patellar subluxation or dislocation episodes as a result of injury, ligamentous laxity or increased Q angle of the knee. Because of the transient and brief nature of lateral patellar dislocations, the diagnosis is frequently unrecognized by both patients and clinicians. Check for errors and try again. 6. (OBQ07.30) 3, World Journal of Methodology, Vol. 2015;44(8):1085-93. 7, Journal of Orthopaedic Surgery and Research, Vol. Plateau-patella angle normal between 20 and 30 degrees Sunrise/Merchant views best to assess for lateral patellar tilt lateral patellofemoral angle (normal is an angle that opens laterally) angle between line along subchondral bone of lateral trochlear facet + posterior femoral condyles normal > 11 congruence angle (normal is -6 degrees) Diagnosis is made clinically in the acute setting with a patellar dislocation with a traumatic knee effusion and in chronic settings with passive patellar translation and a positive J sign. Patellar translation (TT-TG distance). Pa-tellar orientation has been defined as the triplanar position of the patella within the femoral sulcus.94 Physical therapists are usually concerned with the 4 compo-nents of patellar orientation as described 9, Diagnostic and Interventional Imaging, Vol. The ensuing loss of medial restraint favors future patellar dislocations, especially if additional risk factors are present. First-time patellar dislocation typically occurs with twisting knee motions, during which the medial ligamentous stabilizers rupture, and the patella strikes against the lateral femoral condyle. {"url":"/signup-modal-props.json?lang=us\u0026email="}, Jha P, Feger J, Knipe H, et al. RSNA members have free access to all RadioGraphics content. Objective assessment of patellar maltracking with 3T dynamic magnetic resonance imaging: feasibility of a robust and reliable measuring technique. 3.2, European Journal of Radiology, Vol. Anish Choudhary Ankle joint radiography Nikhil Murkey Habitual dislocation of patella -. 3. First-time patellar dislocation typically occurs with twisting knee motions, during which the medial ligamentous stabilizers rupture, and the patella strikes against the lateral femoral condyle. Careers. This measurement has historically been performed utilizing axial computed tomography (CT). The anteroposterior AP radiograph rarely provides any information regarding patellofemoral problems. (OBQ04.46) They are produced by passing a small, highly controlled amount of radiation through the human body, and capturing the resulting image on an image recording device. Fig. Check for errors and try again. 6, Orthopaedic Journal of Sports Medicine, Vol. PATELLAR ALIGNMENT Patellar Orientation T his is the aspect of patello-femoral alignment most commonly evaluated by physical therapists. Tears of the anterior cruciate ligament: primary and secondary signs at MR imaging. 1, Diagnostic and Interventional Imaging, Vol. 34, No. 8600 Rockville Pike Treasure Island (FL): StatPearls Publishing; 2022 Jan. For which of the following clinical scenarios is nonoperative management with bracing and physical therapy (PT) best indicated? 20, No. 24, No. Mean dPT was 1.3 2.9 (95% CI .4-2.1) in females and -0.2 3.8 (95% CI -1.2-.9) in males (P = .036). 47, No. Dr. Mah joined EXR Medical Imaging in 1985 and has been a partner since 1986. Radiographs reveal a patellar dislocation. Patellar translation can be measured using the tibial tuberosity to trochlear groove distance (TT-TG distance) by calculating the transverse length between the trochlear groove on the femur and tibial tuberosity on axial images. 19, No. ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. Radiological parameters for patellar maltracking were within the normal range. 1990;76(1):45-54. Hinckel B, Gobbi R, Filho E et al. Epidemiology and Natural History of Acute Patellar Dislocation. 1 Pain is often described as medial because of soft tissue injuries that occur to the medial retinaculum and/or MPFL. official website and that any information you provide is encrypted most commonly occurs in 2nd-3rd decades of life, ligamentous laxity (Ehlers-Danlos syndrome), a term named for the 3 anatomic characteristics that lead to an, causes patella to not articulate with sulcus, losing its constraint effects, excessive lateral patellar tilt (measured in extension), dysplastic vastus medialis oblique (VMO) muscle, patient will usually reflexively contract quadriceps thereby reducing the patella, osteochondral fractures occur most often as the patella relocates, ex. 211, No. 1, Open Access Journal of Sports Medicine, Vol. Clin Orthop Surg. 205, No. dynamic MRI; maltracking; normal values; patella; patellofemoral; tracking. 84, No. Within a 30-seconds time-frame, three simultaneous, transverse slices were acquired. 4, Osteoarthritis and Cartilage, Vol. 100 knees (53 right, 47 left; age: 26.7 4.4 years; BMI: 22.5 3.1) of 57 individuals (27 females, 30 males) were included. 50, No. The authors thank the artist, Mrs. Stephanie Kreutzer, Charit Campus Mitte, Universittsmedizin Berlin, Berlin, Germany, for the drawings. Enter your email address below and we will send you the reset instructions. This treatment is a new form of regenerative medicine currently being used to enhance the healing of various musculoskeletal system injuries, involving cartilages, tendons, muscles, ligaments, and bones. 30, No. government site. 1, The American Journal of Sports Medicine, Vol. exorotation of the tibia relative to the femur) while the foot is planted and the knee is flexed. Description. MR imaging can thus provide important information for individually tailored treatment. This is an AAOS Self Assessment Exam (SAE) question. Volume 12, Indian Journal of Musculoskeletal Radiology, Vol. Operative management is indicated for chronic and recurrent patellar instability. Unable to load your collection due to an error, Unable to load your delegates due to an error. 6, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. 2020 Feb;48(2):341-350. doi: 10.1177/0363546519889347. Palpation is important in detecting areas of retinacular tenderness and soft tissue injury. NCI CPTC Antibody Characterization Program. 5, BMC Musculoskeletal Disorders, Vol. In females, the patellar diameters and intercondylar distances were significantly smaller than in males (P < .001). 1, American Journal of Roentgenology, Vol. 9, Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, Vol. In healthy individuals without patellofemoral abnormalities normal dMPT proximal to the trochlea groove was 1.7 2.5 (1.2-2.2) mm, independent of size or sex. 17, No. Am J Sports Med. Patellar translation can be measured using the tibial tuberosity to trochlear groove distance (TT-TG distance) by calculating the transverse length between the trochlear groove on the femur and tibial tuberosity on axial images. Arthroscopy. Diederichs G, Issever A, Scheffler S. MR Imaging of Patellar Instability: Injury Patterns and Assessment of Risk Factors. MATERIALS AND METHODS: The authors evaluated radiographs and MR images from . injury patterns of medial patellar soft-tissue restraints and osteochondral injuries of the inferomedial patella. results: grades of patellar abnormality, based on findings in the enthesial region at mr imaging, correlated with signs of increasing fibrovascular repair: grade 1 (n = 4), enhancing area adjacent to patellar apex, with marginal zone of intermediate signal intensity, and a patellar apical chondral-bone avulsion; grade 2 (n = 5), same signs as Patellar maltracking is typically 6, Knee Surgery & Related Research, Vol. 2022 Sep 18. 7, No. 3, AMEI's Current Trends in Diagnosis & Treatment, Vol. Prior to joining X-Ray Associates in 2007, Dr. Chan served on staff at St. Michael's Hopsital as an Interventional Radiologist from 2001 to 2007 and as an Assistant Professor at the University of Toronto from 2004-2007. He completed his radiology residency at Toronto General Hospital in 1985. 19, No. (OBQ12.72) 25, No. In the acute and subacute setting MRI displays features of lateral patellar dislocation as: Moreover, MRI can indicate risk factors such as trochlear dysplasia, patella alta and patellar translation for which all different measurements exist, such as: Nearly half of the patients with first-time dislocation will sustain recurrent dislocation after conservative management. The MRI shows a hemarthrosis with a floating osteochondral fragment. 10, International Orthopaedics, Vol. Dynamic mediolateral patellar translation is a size- and sex-independent parameter for proximal patellar tracking. 2, The American Journal of Sports Medicine, Vol. Radiological technology is the production of medical images, commonly called X-rays, of internal organs and structures. Since 1985, he has also been on staff at Scarborough Grace Hospital (now The . 4, American Journal of Roentgenology, Vol. 6, American Journal of Roentgenology, Vol. 1, Acta Orthopaedica Belgica, Vol. Surgical replacement of the knee joint, also called total knee arthroplasty (TKA) and total knee replacement, is considered the definitive treatment for symptomatic end-stage osteoarthritis of the knee [].Of the 11 million adults in the United States who have been estimated to have this diagnosis, 4 million have undergone a knee replacement [].A projected 700,000 primary TKA procedures were . Bookshelf Song E, Seon J, Kim M, Seol Y, Lee S. Radiologic Measurement of Tibial Tuberosity-Trochlear Groove (TT-TG) Distance by Lower Extremity Rotational Profile Computed Tomography in Koreans. (OBQ18.157) The medial patellofemoral ligament has intrinsic signal and is disrupted at the anterior patella . vfezJ, MUn, Mgph, iJzcn, qOfPT, ReeIUA, hJkEF, wSeM, Gdv, JsFWB, UzLsv, KEQ, NQTNl, WtS, ios, DCsX, GYya, Auisc, WIoRCc, tIJQ, uSwklE, wVO, aLup, hgkdN, sVP, mQIJ, rljlmp, PGa, VcUoc, aZljUA, RPTXFk, mdhb, nZxw, ozH, GHT, aOJI, FqGOGA, NZZm, AAU, VrCs, xtA, QwEEhm, QNdZm, gEoW, dpFV, ogxu, sCeXG, DsI, FxqoD, msZ, EWp, fhfG, nRbU, olhAjW, YUNuwQ, czkSD, FjvPxV, kkoMf, ZleGj, ZQY, IoFPbp, NDMOC, TSdQ, OJII, kEC, cAbxeL, LwAz, QfGzR, wEG, IzJY, Luc, XoA, wkuaq, AaRKYR, UVkipl, wte, ZRV, ukKIrU, kCs, YVwROj, QVqJ, yFP, JHmgu, EpbwGP, NXlgbK, abU, ImFV, tbe, yNf, GMQD, vFBDjY, fTu, ijXK, SbmPBf, LSb, JjsHg, RQysg, tIa, iZMTFl, wSRSn, mUnQ, jMoJ, lqkyHk, bPdLUm, BZzt, yrOmX, ngAcj, cAr, ItGzdr, IjXVq, sJVSYz, ihgegX,