Congenital Dislocation Of The Knee Research Articles

Long-term Outcomes of Surgically Treated Congenital Dislocation of the Knee.

Congenital dislocation of the knee (CDK) may be idiopathic or associated with another condition, such as Larsen syndrome or arthrogryposis. Surgical reduction of type-3 dislocation may require quadricepsplasty (QP) or femoral diaphyseal shortening (FS). Because it is unknown which treatment is more effective, we evaluated long-term outcomes using patient-reported questionnaires and gait analysis, comparing results by surgery type and underlying diagnosis. Twelve patients (mean age, 19mo) were treated surgically for CDK from 1985 to 2015 and studied 9 to 30 years postoperatively. Three participants had idiopathic CDK, 5 had Larsen syndrome, and 4 had arthrogryposis. Eleven knees underwent QP and 7 underwent FS. Participants were evaluated in our movement science laboratory and completed patient-reported outcome questionnaires. Data were compared with healthy, age-matched control values at the same visit. Surgically treated knees had less flexion during swing (P<0.01), less overall motion (P<0.01), greater coronal instability (P<0.04), and slower gait (P<0.01) compared with controls. QP knees had more instability in midstance (P=0.03) and less flexion during gait compared with FS knees, less sagittal power generation than controls (P<0.01), and trended toward lower scores on Knee Injury and Osteoarthritis Outcome and Lysholm Knee Questionnaires than FS patients did. The idiopathic group had the gait most similar to that of controls, followed by the Larsen syndrome group and then the arthrogryposis group. The idiopathic group also had a better UCLA Activity Score (P=0.03) than the arthrogryposis group did. Surgical treatment of type-3 CDK will not likely restore normal knee function, suggesting teratologic joint abnormality. In this small series, FS produced better gait mechanics and patient-reported outcomes compared with QP. Not surprisingly, patients with idiopathic CDK had better outcomes than those with a syndromic diagnosis, likely related to having only a single joint affected. Level III.

Congenital dislocation of the knee: A noninvasive treatment method

BACKGROUND: Congenital knee dislocation is a significant topic of interest in the possible application of new reduction techniques immediately after birth. This initiative aims to minimize the consequences of dislocation, ensuring the possibility of normal joint formation and functioning from the very first stages of life. This is not only a technical achievement but also an approach to providing optimal conditions for the health and development of children with congenital knee dislocation.&#x0D; AIM: This study aimed to evaluate the functional and long-term treatment outcomes of congenital knee dislocation using a new patented method.&#x0D; MATERIALS AND METHODS: A total of 120 patients (194 knees) with congenital knee dislocation were examined. The patients were divided into the main group (55 patients, 90 knee joints) and the control group (65 patients, 104 knee joints). The main group received the treatment developed by the authors using an Ergopower ER 7028 vibration massager. In the control group, the traditional method of orthopedic correction of congenital knee dislocation using a Von Rosen splint and circular plaster casts was employed. At the start of treatment, the age of the patients in the main group was Me 28 [Q1 28; Q3 30] hours and that of the control group was Me 30 [Q1 28; Q3 34.5] hours.&#x0D; RESULTS: A comparative analysis of the treatment outcomes of the main and control groups showed that the developed method for correcting congenital knee dislocation using a vibration massager and careful manipulations, in contrast to traditional technology, achieved the most accurate orthopedic correction in 95% of cases, ensured the restoration of the axial profile of the knee joint and its stability, and created conditions for the harmonious growth and development of the lower extremities in adulthood. In the main group, after conservative treatment of congenital knee dislocation using improved technology, indicators for assessing knee joint function (66.7%) and pain relief (98.2%) were excellent after 5 years of observation, which was confirmed by data from a clinical study and use of specialized questionnaires.&#x0D; CONCLUSIONS: The proposed innovative method of conservative orthopedic correction of congenital knee dislocation by vibrovascularization of the thigh muscles is a differentiated approach to conservative treatment, which improved the overall and long-term treatment outcomes.

Midterm treatment results of congenital dislocation of the knee in 14 knees of nine cases.

Patients with congenital dislocation of the knee (CDK) should be promptly treated surgically if conservative measures fail. This study aimed to achieve a better understanding of the diagnosis and management of CDK through sharing our experience and contributing to the existing literature. Nine patients with a total of 14 knees were included in the study. All patients except one were initially treated with gentle manipulation and serial casting. Surgery was performed on patients in whom sufficient joint mobility could not be achieved. Active and passive range of motion of the knees and functional outcome were measured. Of the 14 knees, five were classified as first grade, four as second grade and five as third grade. The mean age of the patients was 4.09 months and the follow-up period was 70 months. The initial mean flexion angle (MFA) was 18.2° (0-90) and the mean extension angle (MEA) was 8.2° (0-15). At the final follow-up, the mean MFA was 109.2° (80-140) and MEA was -2.85° (0 to -10). No patient had instability by the final follow-up. The results were classified as excellent (5 knees), good (5 knees) and moderate (4 knees) according to outcome assessment criteria. The functional outcomes were classified as excellent (7 knees), good (3 knees) and fair (4 knees) according to the functional outcome scoring. Treatment of CDK should be started in the first days of life, and if the desired functional outcome cannot be achieved through conservative treatment, surgical treatment should be planned without delay.

Congenital Dislocation of the Knee in the Delivery Room.

BACKGROUND Congenital dislocation of the knee (CDK) is rare and can cause significant distress in the delivery room to parents and to healthcare providers, especially if the latter are unaware of this condition. It may not be detected by prenatal ultrasound and can be either an isolated finding or associated with other anomalies such as developmental hip dysplasia and genetic syndromes such as Larsen syndrome. Because of the risk of development of contractures, immediate referral to a specialized provider is needed. Poor prognostic factors include an association with a genetic syndrome, limited knee flexion related to severe quadriceps retraction, and absence of anterior skin grooves. A satisfactory outcome can be anticipated in isolated cases with easy reducibility of the knee. CASE REPORT A term baby presented unexpectedly with left knee dislocation after delivery. The providers, unaware of the condition, immediately consulted the orthopedic service, who assisted in the diagnosis, and appropriate management was initiated. The baby had serial casting of the leg, which was applied for almost 3 months, with excellent results on the clinical examination. CONCLUSIONS CDK is a rare finding. The diagnosis is primarily clinical and radiographs are used to confirm and assess the degree of the dislocation. The degree of dislocation is important for management and prognosis. Interventions ranging from serial casting to surgery are required as soon as possible. As the CDK can be associated with genetic syndromes or other dysplasias such as developmental dysplasia of the hip and talipes equinovarus, further evaluation for these conditions is warranted.

Congenital dislocation of the knee – Not commonly seen by pediatricians

Congenital dislocation of the knee – Not commonly seen by pediatricians

Successful Management of a Case of Congenital Dislocation of Knee With Ipsilateral Developmental Dysplasia of Hip

Introduction Congenital dislocation of the knee (CDK) is a rare condition and includes a characteristic hyperextension deformity at the knee with varying degrees of anterior and lateral subluxation. Developmental dysplasia of the hip (DDH) is a common disorder and presents frequently to a pediatrician. DDH with CDK is common, but hip pathology usually remains unnoticed because of more obvious deformity at the knee. Through this case, we aim to highlight the association of CDK with DDH and discuss its management. Case Presentation A preterm, 31-week baby girl, appropriate for gestational age, delivered to a primigravida mother with early antenatal oligohydramnios. At birth, the baby had an externally rotated left lower limb and the knee in hyperextension. A clinical diagnosis of CDK with ipsilateral DDH was confirmed further with a radiological evaluation of the left hip and knee. Staged correction of deformities was done starting with the knee, followed by the hip joint. By the 12th week of life, the knee and hip dislocations were corrected satisfactorily, which remained stable till the last follow-up (6 months). Conclusion CDK can present with an ipsilateral DDH, and this possibility needs attention. Newborns having congenital knee dislocation should undergo hip screening for instability by clinical methods. Ultrasound screening of the hip can be done if clinical examination is inconclusive. Such cases can be managed successfully by staged knee and hip disorder correction.

Management of Anterior Cruciate Ligament Aplasia for the Arthroscopy Surgeons: A Systematic Review.

Anterior Cruciate Ligament Aplasia (ACLA) is a rare condition which can sometimes remain asymptomatic into adult life. Although the quoted incidence is 1.7 per 100,000 live births, it is higher due to these silent cases and can be encountered by the arthroscopy surgeon doing reconstructive procedure for the ACL. The aim of this study is to get information on clinical presentation, imaging, arthroscopy findings and management of the knee in patients with ACL aplasia through a systematic review relevant to the arthroscopy surgeon in making a decision when they encounter such a case. We performed a systematic review of the literature to get information on this condition that may be relevant to the arthroscopy surgeon from PubMed, Ovid full text, Embase and Ovid Medline databases. After exclusions and inclusions, we found 31 articles relevant to the search which included 101 knees. Most of the publications were case reports due to the rarity of this condition. ACLA is commonly associated with Fibular Hemimelia, Congenital Dislocation of the Knee and Proximal Focal Femoral Deficiency (PFFD). Clinical findings, imaging appearances, other associated findings with ACLA have been listed and management options listed and discussed. Patients with ACLA are often asymptomatic and arthroscopic reconstruction of the ACL appears to be a viable option in selected symptomatic cases only. The arthroscopic surgeon should be aware of the clinical picture and intraarticular findings of ACLA to recognize the condition and make a decision on the optimal management. Further studies are required to report on long-term outcomes of the condition in terms of secondary osteoarthritis development as well as the procedures performed. We recommend forming a global registry to study and further understand the aspects of this condition. 4. The online version contains supplementary material available at 10.1007/s43465-022-00651-2.

Congenital dislocation of the knee with bilateral absence of the fibula and suspected Apert syndrome – case report

Congenital dislocation of the knee is a rare deformity, with an unknown etiology. The treatment of this malformation depends on its extensiveness and applies both conservative approach and surgical procedures. The aim of this study is to evaluate treatment outcomes obtained in the patient with congenital dislocation of the right knee and other multiple abnormalities of the motor system as well as the suspicion of Apert syndrome. Between 2005 and 2019, patient with congenital knee dislocation was treated surgically in two medical centers. Authors performed a retrospective analysis of available data from medical archives. The patient first presented to the authors of this study at the age of nine months. Imaging diagnostics revealed complete luxation of the right knee, grade III according to Leveuf and club feet with no fibula bones in the lower legs. The objective of the multi-stage surgical treatment was to enable the patient to walk. Stage one involved a reposition of the congenital right knee dislocation following the Curtis and Fisher technique. The next stage involved a foot surgery – first the left one and then the right. At the age of 5, during the follow-up, the patient was very active: he kept walking, running and jumping and both his feet were in the right position. However, in the following year, a gradual increase of rotation disorders was observed in both lower legs. When the child was 6 years, he underwent derotation osteotomies in both tibia bones. Next, at the age of 12, he underwent anterior femoral hemiepiphysiodesis around right knee with two 8-plates. Plates were removed when he was 14. The last follow-up took place when the patient was 14. The patient is 100% able-bodied and can walk on his own. To sum up, patients with congenital knee dislocation make up a highly complex group that requires multidisciplinary care and frequently also multistage treatment.

Congenital dislocation of the knee in combination with Meyer-Gorlin syndrome: A case report

BACKGROUND: Meyer-Gorlin syndrome is a rare genetic and autosomal recessive disease that is characterized by the classical triad, including, microtia, very small size or complete patellar absence, and nanism.&#x0D; CLINICAL CASE: Herein, presented the first clinical case description of a Russian patient with Meyer-Gorlin syndrome in combination with congenital anterior shin dislocation. The main clinical disease manifestations are characterized by a combination of microtia, patellar pathology, and dwarfism.&#x0D; DISCUSSION: In the practice of pediatric orthopedic surgeons, cases of congenital knee dislocations are extremely rare, especially as part of any syndromes, which cause interest in the presented clinical case publication. Our patient analysis, as well as the patients described in the literature, showed the presence of typical clinical manifestations, which allowed us to suspect the presence of Meyer-Gorlin syndrome during a clinical examination.&#x0D; CONCLUSIONS: This report is the first case of combined congenital knee dislocation and Meyer-Gorlin syndrome with a diagnostic triad (short stature, microtia, and patellar aplasia) in the Russian Federation. Conservative treatment with constant traction and flexion must be carefully performed to avoid complications. Without the effect of conservative therapy, surgical treatment is indicated.

Current views on the management of congenital dislocation of the knee based on current data on the outcomes of orthopedic treatment in these patients

Despite the rapid progress in medicine, today there is no clear protocol for the management of patients with such a rare disease as congenital dislocation of the knee (CDK). Analysis of the data shows that in the main percentage of cases, after ineffective conservative treatment, patients undergo late surgical intervention, which entails great number of complications and does not improve outcomes. This trend is associated with the lack of strict time limits for the start of medical care due to the lack of guidelines regulating the work.&#x0D; Aim of the study was study modern approaches to conservative and surgical treatment of patients with congenital dislocation of the knee based on a systematic analysis of the literature.&#x0D; Systematic analysis of literature sources on databases PubMed, Scopus, eLibrary, CyberLeninka, bibliography of key articles.&#x0D; Preparing the preliminary plan of correction and early initiation of treatment of congenital dislocation of the knee significantly increases the rate of positive outcomes of this disease. It is worth noting that using a less invasive approach to initiating treatment of congenital dislocation of the knee avoids a number of complications. Based not only on the classification of the stage of the severity, but also on the degree of contracture of the quadriceps muscle, it is possible to determine the possibilities of restoring the work of the joint, which proves the need to improve the knowledge gained.&#x0D; There is a need to organize the provision of medical care to patients with congenital dislocation of the knee on the basis of improved classifications that correspond to modern ideas about the outcomes of orthopedic treatment in patients with CDK.

Freeman-Sheldon Syndrome with Stiff Knee Gait - A Case Report.

Introduction:Freeman-Sheldon syndrome (FSS), also known as the distal arthrogryposis (DA) type 2A, is a rare congenital anomaly. We report a unique case of the DA type 2A with mixed clinical features and the unusual presentation of bilateral congenital dislocation of the knee but had unassisted stiff knee gait.Case Report:A 5-year-old female child presented to the clinic with the complaint of inability to bend both knees since birth. She had an unassisted bipedal gait, but could not squat, cross-leg sit, run, and climb stairs without assistance. Her youngest brother had a similar presentation but succumbed to death at the age of 5 months due to respiratory distress. Clinical features were in the favor of FSS. Her serum creatinine kinase level was normal and the electromyography of bilateral tibialis anterior and abductor pollicis brevis was not suggestive of the myotonia. Radiograph of the skull showed cooper beaten skull appearance whereas bilateral pelvis with the hip showed following changes in the right hip; decrease femoral epiphysis height, horizontal proximal femoral physis, and the coxa brevia. She was initially managed conservatively by weekly stretching, manipulation, and casting. As a result, she could flex her knee up to 20°. Although the quadricepsplasty might be helpful for the persistent extension deformity, there was marked quadriceps weakness which could make it harder for the child to stand and walk. In addition, the abnormal muscle physiology in FSS may result in unfavorable outcomes after the surgery. Moreover, a consideration of the surgical aspect is not free of risks which include difficult endotracheal intubation, vein access, and malignant hyperthermia.Conclusion:FSS is a rare congenital anomaly that should be differentiated from another syndrome of the close resemblance, Sheldon Hall syndrome and Schwartz Jampel syndrome which are other rare autosomal recessive disorders characterized by myotonia and the chondrodysplasia. Conservative management has still a role in bilateral knee involvement especially if the patient is an independent walker.

Ultrasonographic measurement of the dimensions of proximal and distal patellar fragments after Niebauer-King Procedure for the management of congenital dislocation of the knee.

The aim of this study was to ultrasonographically measure the dimensions of the proximal and distalpatellar fragments to determine whether postoperative growth differences existbetween the fragments in children with congenital dislocation of the kneetreated by Niebauer Kings quadricepsplasty. This retrospective study included six congenitaldislocated knees of four children with arthrogryposis multiplex congenita (AMC)(3 girls; mean age = 40 months; age range = 9-44 months), presented with severe hyperextension knee contractures,which were treated by Niebauer-King's quadricepsplasty.The transverse, craniocaudal, and anteroposterior dimensions of the patellaewere measured ultrasonographically 20 (range = 6-42) months postoperatively by a singleradiologist. The mean transverse, craniocaudal, and anteroposteriordimensions of proximal and distal halves of the patellae were: 11.46 (7.0-16.9)-10.5 (8.0-14.4); 17.4 (14.0-21.0) -16.68 (14.5-19.3); 6.76 (5.6-7.9) -7.76 (7.0-9.4) mm respectively. There was no significantdifference in craniocaudal and transverse dimensions, but the anteroposteriordimension (thickness) of the distal patellae articulating the knee joint had agreater thickness (P = 0,01). Evidence from this study has shown that a bettergrowth can be expected in the distal fragment of the patella compared with theproximal fragment following treatment with Niebauer-King's quadricepsplasty in children with congenital dislocation ofthe knee. Level IV, Therapeutic Study.

Congenital knee dislocation. Therapeutic protocol and long-term functional results

Background and objectiveCongenital knee dislocation is a very rare entity, characterised by deformity in genuine recurvatum present at birth, and there is currently no consensus on the optimal treatment. The aim of the present study is to analyse the functional results and long-term complications after the application of a protocol of therapeutic action for the management of congenital knee dislocation (CKD) created in a reference centre for child orthopaedics. Materials and methodsRetrospective descriptive study of patients with congenital dislocation of the knee who followed CRPL between January 1997 and December 2010. Demographic variables, type of treatment, functional outcomes at the end of the follow-up, complications and relapses were studied. The conservative treatment consisted of serial casts, leaving the surgical treatment for cases in which passive flexion was not achieved above 30° or the conservative treatment failed. Results9 patients (11 knees) met the inclusion criteria. The 66.7% were girls and the average follow-up was 15 years (9-22). In all cases, conservative treatment was initiated. Of the 11 knees treated, less than half (36%) required surgery. The average Lysholm questionnaire was 90.3 points, the WOMAC pain 0.4 (0–1), WOMAC stiffness 1.8 (0–6) and WOMAC function 3.8 (1–12). ConclusionsThe existence and application of the PLCR protocol in a pathology as rare as congenital knee dislocation suggests good long-term functional results with few complications and no recurrences.

Congenital dislocation of the knee: a morphological study

Background. Congenital knee dislocation is a rare disease of the musculoskeletal system (1 in 100,000 live births). In the literature, few studies have described the anatomical changes characteristic of this pathology, which are only revealed during surgical treatment.&#x0D; Aim. This study aimed to evaluate the pathomorphological features of the ligamentousarticular apparatus and thigh muscles with congenital knee dislocation on autopsy material.&#x0D; Materials and methods. The study included two fetuses with bilateral congenital knee dislocation after spontaneous miscarriage at 18 and 20 weeks of gestation and one stillborn fetus with bilateral congenital knee dislocation at 29 weeks of gestation. The comparison group was composed of two fetuses after spontaneous miscarriages at 18 and 20 weeks of gestation and one stillborn fetus at 25 weeks of gestation without anomalies of the lower extremities.&#x0D; Results. Various abnormalities and displacements of the anatomical structures, as well as degenerative dystrophic changes in the soft tissues during histological examination, were found. Pathomorphological changes in the control group were not detected.&#x0D; Conclusion. Pathomorphological changes are the main manifestations of congenital knee dislocation in the studied fetuses.

Luxación congénita de rodilla. Protocolo terapéutico y resultados funcionales a largo plazo

Background and objectiveCongenital knee dislocation is a very rare entity, characterised by deformity in knee recurvatum present at birth, and there is currently no consensus on the optimal treatment. The aim of the present study is to analyse the functional results and long-term complications after the application of a protocol of therapeutic action for the management of congenital knee dislocation (CKD) created in a reference centre for child orthopaedics. Materials and methodsRetrospective descriptive study of patients with congenital dislocation of the knee who followed CRPL between January 1997 and December 2010. Demographic variables, type of treatment, functional outcomes at the end of the follow-up, complications and relapses were studied. The conservative treatment consisted of serial casts, leaving the surgical treatment for cases in which passive flexion was not achieved above 30° or the conservative treatment failed. Results9 patients (11 knees) met the inclusion criteria. The 66.7% were girls and the average follow-up was 15 years (9-22). In all cases, conservative treatment was initiated. Of the 11 knees treated, less than half (36%) required surgery. The average Lysholm questionnaire was 90.3 points, the WOMAC pain 0.4 (0-1), WOMAC stiffness 1.8 (0-6) and WOMAC function 3.8 (1-12). ConclusionsThe existence and application of the PLCR protocol in a pathology as rare as congenital knee dislocation suggests good long-term functional results with few complications and no recurrences.

VP13.04: Prenatal diagnosis of a congenital knee dislocation

Congenital dislocation of the knee (CDK) or congenital genu recurvatum is a rare abnormality of the musculoskeletal system, with an incidence of 1 per 100,000 liveborn infants. It is typically associated with other joint dislocations and deformities at different body locations, like hip and foot, and may occur isolated or as part of different conditions like arthrogryposis multiplex congenita, myelomeningocele, and or Marfan, Ehlers-Danlos and Larsen syndromes. Timely prenatal diagnostics and treatment during the initial days of life can help avoid the development of disabilities in a child. A 27-year-old woman, gravida 2 para 1, with epilepsy controlled with levetiracetam, was referred to our centre at the 18th week of gestation due to abnormal position of the lower limbs with consisting of permanent hyperextension and club foot on ultrasound performed at 17 weeks of gestation. The karyotype was a normal 46,XX with normal muscular and skeletal dystrophies panel. Pregnancy underwent uneventfully and at 39 weeks a 2,780g female newborn with an Apgar score of 9/10/10 delivered by elective Caesarean section. The newborn was evaluated by the orthopedist, who confirmed the diagnosis of CDK and club foot. Bilateral casts were placed on both knees after manual reduction. The baby is keeping the follow up in the hospital, with progressive improvement of his condition. CDK is a well-known anomaly. However prenatal reports are scarce. Prenatal diagnosis of CDK is possible with ultrasonographic examination. Etiologic factors can be described as being extrinsic, due to abnormal intrauterine pressures and leading to intrauterine malposition; or intrinsic, due to genetic abnormalities and neuromuscular imbalance. Concerting treatment, early and appropriate orthopedic manoeuvres are mandatory in order to improve the prognosis.

Non-operatively corrected congenital knee dislocation: A rare disorder

Congenital dislocation of the knee (CDK) is an exceedingly rare but correctable congenital deformity. It consists of a spectrum from subluxation to complete dislocation. Diagnosis is usually made clinically at birth, based on pathologic hyperextension of the knee, and confirmed by radiography.

Teenage Female with Knee Pain and Instability

Congenital dislocation of the knee, result- ing from an absence of the cruciate ligaments, is a condition affecting 0.017 per 1000 live births (1). Although very rare, it has drawn the attention of or- thopaedic surgeons and radiologists because it is associated with other congential anomalies. This paper presents abnormalities that are isolated to the knee and without evidence of associated syndrome. The absent anterior cruciate ligament (ACL) is associated with a hypoplastic posterior cruciate ligament (PCL), a shallow femoral notch, and hypoplastic tibial spines seen with radiographic and magnetic resonance imaging. The objective of this article is to review the clinical presentation and imaging fndings associated with congenitally absent ACL.

Surgical management of the congenital dislocation of the knee and hip in children presented after six months of age

PurposeCongenital dislocation of the knee and hip is a rare congenital disorder. The specific aim of the study was to evaluate the clinical and radiological outcomes of the children with congenital dislocation of the knee and hip who presented after six months of age.MethodsAll the consecutive children with congenital dislocation of the knee and hip joints were retrospectively reviewed. We included cases that were treated after six months of age and followed up for a minimum of two years. Twenty-four children with congenital dislocation of the knee and hip (thirteen with ligamentous laxity, eleven children with stiff joints) were included. The knee was dislocated in 45 limbs; the hip was dislocated in 40 instances. The knee joint dislocation was treated with quadricepsplasty in all twenty-four children (45 knees). The hip dislocation (n = 32) was addressed with either closed reduction (n = 8) or open reduction of the hip (n = 24). Eight hip dislocations were not addressed. The outcome of the hip and knee was evaluated.ResultsThe clinical and radiological outcomes were better in children with ligamentous laxity than without laxity. Twenty-two children were community walkers. An orthosis was needed in eight children. The frequency of spontaneous reduction of unreduced dislocation of the hip was noted in three children (5/8 hips).ConclusionOutcome in combined dislocation of knee and hip is good in most cases with surgical interventions. The outcome is better in children with ligamentous laxity. Spontaneous reduction of the dislocated hips might be achieved after gaining knee flexion following knee surgery for congenital the knee in a few cases.

Prenatal ultrasound diagnostic clues of congenital dislocation of the knee

Objective To explore prenatal ultrasound diagnostic clues of congenital dislocation of the knee(CDK). Methods The prenatal ultrasonographic features of 13 CDK fetuses diagnosed from January 2013 to December 2018 in the Third Affiliated Hospital of Zhengzhou University were retrospectively analyzed, combined with the results of gene detections and pathological findings. Results Thirteen fetuses were diagnosed by prenatal ultrasound during the second trimester. Two-dimensional and three-dimensional ultrasound showed dislocation of the knee(unilateral in 3 cases and bilateral in 10 cases). All cases were accompanied with multiple abnormalities, including talipes(5 cases), overlapping fingers(2 cases), short nasal bone(1 case), thicken nuchal fold(1 case), narrow thorax(1 case), abnormal vertebral development(1 case), etc. Ultrasound diagnosis included Larsen syndrome in 2 cases, arthrogryosis multiplex congenital in 3 cases, asphyxiating thoracic dysplasia in 1 case, and congenital dislocation of the knee in 7 cases. CDK was confirmed in all fetuses after termination of pregnancy. Three of them were known to undergo chromosome examinations with normal chromosomal microarray analysis (CMA). One case was confirmed to be Larsen syndrome by further second-generation sequencing combined with first-generation sequencing screening, suggesting there was FLNB gene mutation. Conclusions CDK can exist isolated, and it can also be a common manifestation of various diseases. Therefore, attention should be paid to other associated abnormalities in the prenatal detection of knee flexion, and further detection of related genes can provide valuable information for genetic counseling. Key words: Prenatal ultrasonography; Fetal; Congenital dislocation of the knee; Gene