Medial patellofemoral ligament injury patterns and associated pathology A thorough examination of the knee is then performed including presence of effusion, localization of pain, assessment of patellar translation, patellar apprehension, presence of a J sign (visual lateralization of the patella as it disengages from the trochlea when extending the knee), and a measurement of the Q angle along with ligamentous and meniscal testing. Knee CT images in the early post-operative period in a 19-year-old male with history of patellar maltracking. AJR Am J Roentgenol. Ellas et al. 2010 Aug;36(4):353-60. doi: 10.1007/s00068-010-9165-2. Biomechanical evaluation of lateral patellar dislocations. Privacy 25a) Axial proton density-weighted images at initial injury (left) and 5 months later demonstrate progression of medial retinacular and MPFL scarring (arrows) in this patient with trochlear dysplasia and chronic patellofemoral instability with a history of multiple prior dislocations. On the other hand, the PTI is significantly altered with knee flexion [37]. By using this website, you agree to our Unauthorized use of these marks is strictly prohibited. Skeletal Radiol. It is measured at the mid-point of the patella on the axial slices [48]. Bethesda, MD 20894, Web Policies One of the more common MPFL reconstruction procedures uses a single hamstring tendon graft passed through the medial intermuscular septum at the adductor magnus insertion fixed by an anchor in the femoral condyle and sutured or anchored to the superomedial pole of the patella11. MeSH Patellar maltracking: an update on the diagnosis and treatment strategies, https://doi.org/10.1186/s13244-019-0755-1, http://creativecommons.org/licenses/by/4.0/. Trochlear depth=[(a+b)/2]c, Lateral trochlear inclination measurement on axial MRI. Manage cookies/Do not sell my data we use in the preference centre. Google Scholar, Miller TT, Staron RB, Feldman F (1996) Patellar height on sagittal MR imaging of the knee. Patellar tracking refers to the dynamic relationship between the patella and trochlea during knee motion [1]. (27a) Axial and (27b) coronal fat suppressed proton density-weighted images in a patient who experienced recurrent patellar dislocation following surgery. As the knee joint ranges from extension to flexion, the articular surface area of the patella is in contact with the femur changes. Imaging, particularly MRI, can detect subtle features that could lead to the diagnosis, probably even more importantly when there is no clear history of patellar dislocation or before its development. Military Health System Europe > Clinics > Grafenwoehr Army - TRICARE Additionally, return to sport can be as low as 45%, leaving many patients searching for further management options [12]. 8600 Rockville Pike 1993;161(1):109-13. The most accepted indication for surgical management of patellar instability is the presence of a large displaced osteochondral fracture or loose body. J Bone Joint Surg Br 87:3640, Wechter J, Macalena J, Arendt EA (1994) Lateral patella dislocations: history, physical exam, and imaging. It has proven to be both sensitive and specific in the detection of hyaline cartilage abnormalities [4]. Bull NYU Hosp Jt Dis 67:2229, Dupuy DE, Hangen DH, Zachazewski JE, Boland AL, Palmer W (1997) Kinematic CT of the patellofemoral joint. lateral patellar retinaculum tear or invasion. Stretching this ligament keeps the patella in place and the ligament healthy. First, a line is drawn paralleling the posterior femoral condyles surfaces. et al. Radiographics 30:961981, Tscholl PM, Wanivenhaus F, Fucentese SF (2017) Conventional radiographs and magnetic resonance imaging for the analysis of trochlear dysplasia: the influence of selected levels on magnetic resonance imaging. Background Lateral Patella dislocations are common injuries seen in the active and young adult populations. Magnetic Resonance Imaging Characteristics of the Medial Patellofemoral Ligament Lesion in Acute Lateral Patellar Dislocations Considering Trochlear Dysplasia, Patella Alta, and Tibial Tuberosity-Trochlear Groove Distance Reference article, Radiopaedia.org (Accessed on 02 May 2023) https://doi.org/10.53347/rID-27273, {"containerId":"expandableQuestionsContainer","displayRelatedArticles":true,"displayNextQuestion":true,"displaySkipQuestion":true,"articleId":27273,"questionManager":null,"mcqUrl":"https://radiopaedia.org/articles/lateral-patellar-dislocation/questions/2391?lang=us"}, Case 14: transient lateral patellar dislocation, see full revision history and disclosures, 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, medial retinacular abnormalities (ranging from strain to complete disruption) with adjacent periligamentous edema and hemorrhage, lateral displacement of patella (not necessarily seen in transient dislocation), medial patellar contusion +/- corresponding lateral femoral condyle contusion, direct trauma to lateral knee:normally no patellar contusion. Medial patellar. Specialists of neuroradiology and vascular neurosurgery decided over the modality assignment. Patellar sleeve avulsion fracture in a patient with Sinding-Larsen [Google Scholar] 6. Migliorini F, Marsilio E, Cuozzo F, Oliva F, Eschweiler J, Hildebrand F, Maffulli N. Life (Basel). Pedersen ME, DaCambra MP, Jibri Z, Dhillon S, Jen H, Jomha NM. (26a) An axial proton density-weighted image reveals trochlear dysplasia (line, indicating facet asymmetry and a shallow trochlear groove), ossification in the medial retinaculum and MPFL attachment anteriorly (short arrow) and diffuse scarring of the medial retinaculum (arrowheads)--these findings indicate chronic patellofemoral instability. MR imaging can help define patellar retinacular and associated osteochondral injuries, which may be clinically useful information. It runs obliquely and transversely and inserts on the patella and the patellar tendon, and is composed of two layers. In one MRI study, 76% of cases of prior lateral patellar dislocation showed medial retinacular injury at its patellar insertion and 30% at its midsubstance, and injury of the femoral origin of the MPFL was identified in 49% of the cases [49]. 1). (1a) A single fat-suppressed proton density-weighted coronal image. High resolution magnetic resonance imaging of the patellar retinaculum: normal anatomy, common injury patterns, and pathologies. Created for people with ongoing healthcare needs but benefits everyone. MRI Web Clinic, August 2010. https://radsource.us/patella-alta-and-baja/. Clin Sports Med 21:521546 x, Article Distal neurovascular examination also needs to be performed [16]. Advantages of CT over plain radiography include its cross-sectional capability and ability to generate multiplanar reformations. PubMed Central The patellar retinaculum and the MPFL are seen on MRI as well-defined low-signal-intensity bands. A typical bone bruise is seen within the anterolateral aspect of the lateral femoral condyle (asterisk). As the knee joint ranges from extension to flexion, the articular surface area of the patella is in contact with the femur changes. A bone bruise occurs anterior to this site of impaction as the patella reduces with knee extension. a Sagittal PD knee MRI showing the method of assessing the InsallSalvati index, calculated as the ratio of the patellar tendon length at its inner aspect (white dashed line) to the greatest diagonal length of the patella (white line). (1a) A single fat-suppressed proton density-weighted coronal image is provided. The stifle joint of the pampas deer . Axial PDFS MR image showing MPFL disruption (open arrow) and trochlear dysplasia (arrowheads). In general realignment surgery such as tibial tubercle transfer should be strongly considered in patients with TT-TG > 15mm (borderline) and typically should be performed in patients with TT-TG > 20mm. The MPFL is also stripped from the femoral attachment (long arrow). 2023 Apr;47(4):973-981. doi: 10.1007/s00264-023-05707-y. Sports Med Arthrosc Rev 25:7277, Gillespie H (2012) Update on the management of patellar instability. The most important soft tissue passive stabilizers involved in patellofemoral dislocation injuries have traditionally been referred to as the MPFL and the medial retinaculum. (18a) A 13-year-old female following acute patellar dislocation. Findings typically associated with acute lateral patellar dislocation were also assessed and recorded (present or absent) including characteristic bone bruises and osteochondral injuries involving the patella, lateral trochlear facet, and lateral femoral condyle. At less than 30 of flexion, asymptomatic knees may demonstrate physiologic patellar tilt or subluxation. The lateral retinaculum provides significant additive support to the medial stabilizers. The superficial layer originates from the lowest fibers of the iliotibial band and from an extension of vastus lateralis fascia. 1. These prevailing anatomic indices feature prominently into the probability of recurrence, and understanding their variability and pathophysiology is critical to successful management of these patients. It may occur without patellar lateralization. The objective of this paper was to describe the anatomy of the stifle joint (Articulatio genus) of the pampas deer (Ozotoceros bezoarticus, Linnaeus, 1758) by dissection and imaging studies. Materials and methods: Twenty-two male patients (age range 20-45 years) with posttraumatic knee stiffness following distal femoral fractures underwent Thompson's quadricepsplasty where knee flexion range was less than 45. Recent literature does not encourage the use of lateral release, since this can increase patellar instability. Discussion. Eur J Trauma Emerg Surg. In this section, we will emphasize the role of MRI and discuss how CT can also have value when assessing patellar maltracking. Medial retinacular complex injury in acute patellar dislocation: MR findings and surgical implications. It is composed of Lockwood's ligament (inferior suspensory ligament), the lateral extension or horn of the levator aponeurosis, the continuations of the pretarsal and preseptal muscles, and the check ligament of the lateral rectus muscle. provided a morphologic classification system for trochlear dysplasia describing four types [26,27,28]. This is often secondary to an underlying structural abnormality. What is the diagnosis? The joint line is scanned for lateral meniscal pathology, with varus stress applied as needed. Lateral Patellar Dislocation. Guidelines and Gamuts in Musculoskeletal Ultrasound. 11 Lind M, Jakobsen B, Lund B, et al. However, subtle sprains are seen at the anterior medial retinaculum (arrowhead) and posterior MPFL (arrow) along with a large joint effusion. Knee Surg Sports Traumatol Arthrosc 22:23882395, Escala JS, Mellado JM, Olona M, Gin J, Sauri A, Neyret P (2006) Objective patellar instability: MR-based quantitative assessment of potentially associated anatomical features. Fractures may be caused either by excessive force through the extensor mechanism or by a direct blow. Objective: Must rule out a tight iliotibial band (ITB) and weak quadriceps muscles (Juhn). Am J Sports Med 32:11141121, Tsavalas N, Katonis P, Karantanas AH (2012) Knee joint anterior malalignment and patellofemoral osteoarthritis: an MRI study. 5. Correspondingly, the patella must shift slightly medially during early flexion to engage the trochlear groove. Clin Radiol 59:543557, Ali SA, Helmer R, Terk MR (2010) Analysis of the patellofemoral region on MRI: association of abnormal trochlear morphology with severe cartilage defects. Areas of scarring and osteochondral lesions become more common as the frequency of patellar dislocation increases. Because the diagnosis of lateral patellar dislocation is often unsuspected, MR provides valuable diagnostic information in such cases. A commonly used one is the InsallSalvati ratio of patellar tendon length: patellar length. 2012;40(4):837-844. The tight structures of the knee such as the lateral retinaculum need to be stretched and mobilized. The https:// ensures that you are connecting to the MRI is the imaging modality of choice in the assessment of patellar maltracking, as a virtue of what it can reveal (Table1). The patients are then J-braced for 3 to 6 months for all sports activities. Correspondence ML: [emailprotected] Submitted 07-19-2011. PubMed Central Patellar maltracking occurs as a result of imbalance of this relationship often secondary to anatomic morphologic abnormality. Rev Chir Orthop Reparatrice Appar Mot 76:4554, CAS The conditions are presented anatomicallyanterior, lateral, medial, or posteriorwith common etiologies, history and physical exam findings, and diagnosis and treatment options for each (see Table, page 28). Arthroscopy 35:537543, Mountney J, Senavongse W, Amis AA, Thomas NP (2005) Tensile strength of the medial patellofemoral ligament before and after repair or reconstruction. 0000070933 00000 n 0000192215 00000 n 0000212094 00000 n Usually, young individuals, particularly women, suffer the consequences of this disorder [2]. Oper Tech Sports Med 6:247258, Dejour H, Walch G, Nove-Josserand L, Guier C (1994) Factors of patellar instability: an anatomic radiographic study. Most, however, agree regarding the importance of the MPFL and its role as the strongest restraint to lateral patellar displacement. official website and that any information you provide is encrypted Therefore, the management of patellar maltracking remains controversial and decisions need to be made on an individual patient basis with surgical management being reserved for those patients with documented recurrent lateral patellar instability. The clinical evaluation can be more challenging in the absence of a dislocation history, and in this scenario, imaging can have a critical role. Int Orthop 34:311316, Donell ST, Joseph G, Hing CB, Marshall TJ (2006) Modified Dejour trochleoplasty for severe dysplasia: operative technique and early clinical results. (13a) A line is drawn between the cortex of the lateral trochlear facet on the most superior axial image showing cartilage. As the knee progresses through greater flexion, the contact surface becomes more proximal on the patella. Patellar maltracking is a disorder that often affects the young active individuals. Nearly 50% of all first-time dislocators will sustain further dislocations. Patellar dislocation accounts for ~3% of all knee injuries and is commonly seen in those individuals who participate in sports activities. It is a recognized cause of anterior pain and in extreme cases presents as acute and often recurrent patellar dislocation, which is usually transient. Medial retinacular complex injury in acute patellar dislocation: MR Knee Surg Sports Traumatol Arthrosc 22:26552661, Seitlinger G, Scheurecker G, Hgler R, Labey L, Innocenti B, Hofmann S (2012) Tibial tubercle-posterior cruciate ligament distance: a new measurement to define the position of the tibial tubercle in patients with patellar dislocation. Zaid Jibri. All authors read and approved the final manuscript. Sonographic Appearances of Medial Retinacular Complex Injury in Subjective: Pain and tenderness on structure (lateral side of patella) (Juhn). Google Scholar, Pfirrmann CW, Zanetti M, Romero J, Hodler J (2000) Femoral trochlear dysplasia: MR findings. They include: pain with compression of patella and moderate lateral facet tenderness, inability to evert the lateral edge of the patella, mainstay of treatment and should be done for extensive period of time, closed chain short arc quadriceps exercises, pain refractory to extensive rehabilitation, ideal candidate has no symptoms of instability, medial patellar glide of less than one quadrant, lateral patellar glide of less than three quadrants, only elevate 1 cm or else risk of skin necrosis, indicated only for instability with lateral translation (not isolated lateral tilt), viewing through superior portal will show medial facet does not articulate with trochlea at 40 degrees of knee flexion, postoperatively the patella should be able to be, patellar instability with medial translation, 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), Proximal Tibiofibular Joint Ganglion Cysts, Pre-Participation Physical Exam in Athlete, Concussions (Mild Traumatic Brain Injury). Over 100 different procedures have been described for the treatment of patellar instability, and this reflects the various causes for instability and lack of current gold standard [66, 69, 72]. The femoral attachment of the transverse band of the MPFL is not always discretely visible, and therefore secondary signs on MRI such as fluid, edema, and soft tissue thickening at the attachment indicate MPFL injury. The vastus medialis oblique (VMO) provides active stability of the patella. Acta Orthop Scand 68:419423, Deie M, Ochi M, Sumen Y, Adachi N, Kobayashi K, Yasumoto M (2005) A long-term follow-up study after medial patellofemoral ligament reconstruction using the transferred semitendinosus tendon for patellar dislocation. Techniques for quantifying trochlear dysplasia with MRI have been standardized and shown to be accurate and reproducible in assessing lateral trochlear inclination, facet asymmetry, and trochlear depth8,9. Eur Radiol 22:418428, Sonin AH, Pensy RA, Mulligan ME, Hatem S (2002) Grading articular cartilage of the knee using fast spin-echo proton density-weighted MR imaging without fat suppression. RadioGraphics 2010; 30: 961-981. 2010;30(4):961-81. Before The lateral patellar retinaculum is less commonly injured than the medial patellar retinaculum, however it is often disrupted during surgery to correct abnormal lateral patellar tracking or dislocation 3. 2023 Lineage Medical, Inc. All rights reserved, Knee & Sports | Lateral Patellar Compression Syndrome. High resolution magnetic resonance imaging of the patellar retinaculum Int Orthop 34:305309, Biedert RM, Albrecht S (2006) The patellotrochlear index: a new index for assessing patellar height. CAS The patellar tendon may tear when the knee is bent and the foot planted, like when landing from a jump or . If the lateral retinaculum tendon is tight enough to pull the patella out of the trochlear groove, a lateral release procedure can loosen the tissue and correct the patellar malalignment. It is not until beyond 90 of flexion that the odd facet engages the medial femoral condyle and plays a role in load sharing along with lateral facet [6, 7]. The clinical evaluation of patellar maltracking is often challenging, Imaging can detect subtle features that could lead to early diagnosis, Imaging can detect predisposing factors for patellar maltracking and associated structural changes, Management decisions are made on individual basis with imaging playing a vital role. This procedure involves removal of cancellous bone beneath the trochlea followed by fixation of the articular surface [88, 89]. Knee Surg Sports Traumatol Arthrosc 15:13011314, Tom A, Fulkerson JP (2007) Restoration of native medial patellofemoral ligament support after patella dislocation. 2002 Dec;225(3):736-43. doi: 10.1148/radiol.2253011578. The longitudinal stabilizer is the extensor mechanism itself, which is comprised of the quadriceps tendon proximally and the patellar tendon distally. Lateral patellar dislocation refers to lateral displacement followed by dislocation of the patella due to disruptive changes to the medial patellar retinaculum. Several osteotomies have been described including the medializing ElmslieTrillat procedure, the anteromedializing Fulkerson osteotomy, and distalization osteotomy [87]. AJR Am J Roentgenol 1997; 168:1493-1499. The authors would like to sincerely thank Cheryl Kreviazuk for all her efforts in the submission process. The convex articular surface of the patella places it at risk for chondral injury in either the dislocation or the reduction phases of injury. MR imaging of patellar retinacular ligament injuries - PubMed J Bone Joint Surg Am 89:17491755, PubMed The oblique decussation of the MPFL blends with fibers of the superficial MCL. Division of Sports Trauma, Department of Orthopaedics, Aarhus University Hospital, Aarhus, Denmark. Nonoperative treatment is generally recommended in first time dislocators unless there are MRI findings of severe predisposing dysplasia and the presence of a chondral or osteochondral body. PubMed In addition, symptomatic knees may demonstrate normal engagement between the patella and trochlea beyond 30 of flexion. Jibri, Z., Jamieson, P., Rakhra, K.S. PMID: 9168713. Buick Roadmaster Estate Wagon For Sale, Illinois State Police Crash Reports, Articles L
">