There have been several reports on heterozygous loss of function variants in PBX1 associated with congenital anomalies of the kidney and urinary tract (CAKUT). We report three patients harboring de novo heterozygous missense variants in PBX1, who did not have CAKUT, but instead presented with respiratory failure, developmental delay, and, the most important, a unique skeletal phenotype characterized by broad and short clavicles with coracoclavicular ankylosis and broad ischia with premature fusion of the ischiopubic synchondrosis. All the variants are clustered at the last portion of the homeobox domain. This phenotype is consistent with mouse models with functional dysregulation in Pbx1 or its interacting factor, Emx2. This study highlights a previously not reported phenotype affecting the clavicles and ischia due to PBX1 variants and expands the clinical spectrum of PBX1-related disorders.

We present a case of a middle childhood boy who presented to our paediatric emergency department with severe right upper thigh pain, radiating to inguinal/hip area. The pain was sharp in nature, described like a severe cramp which started 10 hours prior to presentation, progressively increasing over time. He denied any recent trauma or infective symptoms, and there were no other associated complaints. On physical examination, he was in tears due to excruciating pain which he could not locate precisely, had tense muscles at the right posterior upper thigh and lower gluteal area and had limping. Also, he had mild right testicular tenderness on examination which he did not complain of before, no skin changes or swelling with normal cremasteric reflex. His investigations were significant for asymmetric ischiopubic synchondrosis on pelvic X-ray. Scrotal ultrasound showed no evidence of testicular torsion. Pelvic MRI showed features consistent with the right ischiopubic synchondrosis osteomyelitis. He spiked a high-grade fever of 40°C within 24 hours of presentation. His blood culture grew methicillin-sensitive Staphylococcus aureus On admission, he was managed initially with ceftriaxone, vancomycin and clindamycin. After the blood culture result, he received ceftriaxone for 2 weeks, followed by oral cefuroxime for another 2 weeks. Pain controlled with ketorolac and paracetamol. Our patient was diagnosed and started on antibiotics within 24 hours from presentation.

Introduction: Enlarged ischiopubic synchondrosis is a frequent finding in radiology. Although it is a normal growth phenomenon, its tumor-like appearance may cause diagnostic confusion. Case Series: We report two cases of pediatric patients presenting with unilateral pelvic pain. Magnetic resonance imaging findings revealed asymmetrical ischiopubic synchondrosis enlargement, mimicking tumoral conditions. Conservative management resulted in clinical improvement. Conclusion: Recognizing this radiological appearance is crucial to avoid unnecessary interventions and differentiate it from more severe pathologies.

Van Neck–Odelberg disease also known as Osteochondritis ischiopubica is a rare form of osteochondritis. Ischiopubic Synchondrosis (IPS) is a temporary cartilaginous joint found between the ischium and inferior pubic ramus present at birth which undergoes complete pre-pubertal ossification. Pain in the groin, lower limb, and/or buttock in the ischiopubic region poses a significant diagnostic challenge in the pre-pubertal age group. Paediatric patients presenting with unilateral pain in the groin and associated limp consist of wide range of differential diagnoses ranging from trauma-induced fractures, infectious disease as well as neoplastic process. A detailed clinical examination with corresponding imaging findings is paramount to arrive at a diagnosis. We present an 11-year-old, right limb dominant boy, a foot-ball player who experienced an acute tenderness in the left groin and buttock as the only concerning symptom post playing a game. After performing clinical examination, laboratory tests, and pelvic / hip radiographic evaluation, the boy was diagnosed with Van Neck-Odelberg disease. Intense sports activities is associated with overuse injuries in children, especially before completing the ossification process. A thorough evaluation and detailed knowledge of this rare condition helps to avoid unnecessary investigations and unwarranted invasive procedures in a resource constrained countries.

Surgical fixation of pediatric pelvic ring injuries is gaining popularity to avoid the poor long-term outcomes of pelvic asymmetry. The surgical techniques and fixation choices depend on the individual injuries affecting the anterior and posterior pelvic ring areas. The immature bony pelvis of young children has anatomic differences including soft bones, elastic ligaments, and the presence of growth centers. Understanding the unique pediatric lesions with unstable pelvic fractures is essential for treatment decisions. Anterior lesions include pubic symphysis disruption through the pubic apophysis, single ramus fractures, pubic rami fractures through the triradiate cartilage, and/or the ischiopubic synchondrosis; ischiopubic ramus infolding injury; or the unstable superior and inferior quadrant lesions. Posterior pelvic lesions include iliac wing infolding and sacroiliac joint dislocation or transiliac (crescent) fracture/dislocations through the iliac apophysis growth plate. Pubic symphysis and sacroiliac disruptions are physeal injuries in children, and they have excellent healing potential. External fixation is an ideal choice for anterior ring fixation including bony and pubic symphysis injuries. Posterior lesions are mostly sacroiliac joint disruptions with iliac apophysis separation that can serve as a landmark for vertical displacement correction. Posterior lesions can be treated by percutaneous iliosacral screw fixation or open reduction techniques.

The authors report the case of a six-year-old child with MRI abnormalities symptomatic of ischiopubic synchondrosis. The concept of "osteochondrose ischiopubic" of Van neck-Odelberg is revised in the light of modern imaging, and the importance of its differentiation from different pathological entities such as osteomyelitis, tumor, fracture or other pathological entities is recalled.

In this study, we evaluated whether it is possible to perform forensic radiological skeletal age estimation via radiological examination of the ilioischial, ischiopubic, and iliopubic synchondrosis regions of the pelvis. This study was conducted by retrospectively examining the abdominopelvic images of individuals aged 8-16 who had applied to the hospital for any reason without having a chronic disorder and who had undergone computed tomography. Two radiologists retrospectively reviewed the images. The BT images of the pelvis ilioischial, ischiopubic, and iliopubic synchondrosis regions were evaluated as follows: 0: open, 1: semiclosed, and 2: closed. The data were evaluated using the SPSS 17 program. Two hundred sixty-three children (118 girls and 145 boys) between the ages of 8 and 16 years without any health problems participated. There was a significant difference between the groups for all the evaluated synchondrosis joints in girls and boys (p<0.001 for each group comparison). We observed that ilioischial, ischiopubic, and iliopubic synchondrosis closed earlier in girls than boys. In addition, we found that the joints were closed at the age of 15 and over in boys and at 14 and over in girls. Some studies have previously evaluated synchondrosis by using computed tomography. We showed that forensic radiological skeletal age estimation could be performed by examining ischiopubic-ilioischial-iliopubic synchondrosis in pelvis computed tomography images. The pelvis is more resistant to decay than other parts of the body. Furthermore, pelvis bones can withst and the effects of postmortem animal attacks for a longer period. Therefore, we believe that forensic age estimation can be made on corpses with no extremity, a damaged chest, or whose only pelvic bones are assessable through the method we use. In our study, the ischiopubic-ilioischial-iliopubic joints were open in those aged nine and under and closed in those aged 15 and above. Ilioischial, ischiopubic, and iliopubic synchondrosis were observed to close earlier in girls than in boys. We consider that our study will be beneficial in the 8-16-year-old age group if used. In addition, our study can be used to determine the radiological bone age in cases with wrist bone abnormalities or wrist amputation.

Van Neck-Odelberg (VNO) disease is a rare osteochondrosis affecting the ischiopubic synchondrosis (IPS). This condition should be included in the differential diagnosis of children with lameness, inguinal pain, and functional limitation of the hip. In imaging tests, it is characterized by asymmetric IPS hypertrophy. We present the clinical case of a 4-year-old child, previously healthy, who visited the emergency department for left inguinal pain and lameness starting on the same day. There was no previous history of trauma or changes in inflammatory parameters. The patient underwent a pelvic radiography and magnetic resonance imaging (MRI), which revealed a radiopaque image with well-defined contours in the left ischiopubic branch, and IPS swelling. With a presumed diagnosis of VNO disease, the patient was medicated symptomatically, with complete recovery in 10 days. Lameness is a frequent reason for medical evaluation in the pediatric population. In subjects up to 5 years old, the most common causes of lameness include transient hip synovitis, septic arthritis, and Legg-Calvé-Perthes disease. In the absence of a history of trauma or infection-related clinical findings, VNO disease should be considered as a hypothesis. Its diagnosis requires a pelvic radiography, usually showing a unilateral fusiform opacification at the ischial level; an MRI may be necessary. The recommended treatment is conservative, with symptomatic recovery in 2 weeks. The knowledge and diagnosis of VNO disease allow a targeted approach, without the emotional burden for the patient and his/her family that may be associated to other conditions.

Background and purpose — Van Neck–Odelberg disease (VND) is a self-limiting skeletal phenomenon characterized by a symptomatic or asymptomatic uni- or bilateral overgrowth of the pre-pubescent ischiopubic synchondrosis. It is frequently misinterpreted as a neoplastic, traumatic, or infectious process, often resulting in excessive diagnostic and therapeutic measures. This study assessed the demographic, clinical, and radiographic features of the condition and analyzed diagnostic and therapeutic pathways in a large single-center cohort. Patients and methods — We retrospectively analyzed 21 consecutive patients (13 male) with a median age of 10 years (IQR 8–13) and a median follow-up of 5 years (IQR 42–94 months), who were diagnosed at our department between 1995 and 2019. Results — VND was unilateral in 17 cases and bilateral in 4 cases. Initial referral diagnoses included suspected primary bone tumor (n = 9), fracture (n = 3), osteomyelitis (n = 2), and metastasis (n = 1). The referral diagnosis was more likely to be VND in asymptomatic than symptomatic patients (4/6 vs. 2/15). More MRI scans were performed in unilateral than bilateral VND (median 2 vs. 0). All 15 symptomatic patients underwent nonoperative treatment and reported a resolution of symptoms and return to physical activity after a median time of 5 months (IQR 0–6). Interpretation — By understanding the physiological course of VND during skeletal maturation, unnecessary diagnostic and therapeutic measures can be avoided and uncertainty and anxiety amongst affected patients, their families, and treating physicians can be minimized.

HISTORY: Patient is a 13 yo female pre-professional ballerina who developed pelvic pain during her training. She was doing an arabesque with her leg in single stance with the opposite leg extended. She then moved to a penché position with her torso leaned forward over a leg in single stance with her legs at 180 degrees. She felt an immediate pop in her left groin. She continued to dance through pain during 6 weeks of intensive ballet training prior to presentation to clinic. Pain described as 3/10, aching in left groin and buttock pain at rest. Pain better with rest and worse with walking, leg extensions and entrechant which is a vertical jump with repeated adduction of feet. She denied any numbness, tingling or weakness. Patient had no prior history of stress fractures, is not menstruating and eats a balanced diet. PHYSICAL EXAMINATION: Tenderness to palpation over left pubic bone. Full pain free ROM in both hips. Special tests positive on the left side included FABER, FADIR, single leg hop and resisted adduction more than abduction. She had 4/5 hip abduction strength in side lying bilaterally. DIFFERENTIAL DIAGNOSIS: 1. Ischiopubic stress fracture 2. Pubic apophysitis at adductor insertion 3. Femoral acetabular impingement 4. Hip labral tear 5. Ischiopubic synchondrosis with stress reaction TESTS AND RESULTS: Pelvis and hip AP and Dunn radiographs: There is a healing fracture of the left inferior pubic ramus, with a faintly visible fracture line and surrounding periosteal reaction. MRI pelvis w/o contrast: Findings consistent with Asymmetric incomplete fusion of the ischiopubic chondrosis with stress reaction. FINAL WORKING DIAGNOSIS: Ischiopubic synchondrosis with stress reaction also known as Van Neck Disease TREATMENT AND OUTCOMES: 1. Patient was made NWB on crutches for 2 weeks at her MRI follow up appointment. 2. At 2 week follow up patient had decreased pain to palpation over left pubic bone. She was progressed to WBAT, PT, no ballet for 6-8 weeks and continue with the sports nutritionist. 3. At 4 week follow up, patient had no pain on physical examination. Patient was progressed to return to barre class for 10 minutes for one week. She could increase her time each week as instructed by her PT. Patient was not allowed to do speed work, jump or move her leg past 90 degrees in abduction, flexion or extension. 4. Patient will follow up in 6 weeks

Edward Herbert (later 1st Baron Herbert of Cherbury) (c.1582-1648) (Fig. 1) has said, “Whoever considers the study of anatomy, I believe will never be an atheist; the frame of man's body, and coherence of his parts, being so strange and paradoxical, that I hold it to be the greatest miracle of nature.” Such a profound statement still resonates some four centuries after Herbert's death. Herbert was born near Wroxeter, Shropshire and was a poet, writer, knight, philosopher, historian, diplomate, and deist. He attended University College, Oxford and was friends with such noteworthy men as Ben Jonson, John, Donne, Issac Casaubon, and the Prince of Orange. He was made sheriff of Montgomeryshire in 1605. This special issue of Clinical Anatomy is devoted to the anatomy of infants and adolescents. Dr. Ali Mirjalili from the University of Auckland has orchestrated an international team of authors who have written on topics including pediatric central venous line placement, differential growth of the abdominal aorta and vertebrae, anatomy of a tongue tie, age-related changes in the inguinal region, pediatric regional anesthesia and a predictive modeling study of the ischiopubic synchondrosis. These studies remind us of the everchanging frame of man's body.

Flaring of the ischiopubic synchondrosis at the time of fusion is a common clinical observation in pediatrics and represents a normal physiological process in skeletal maturation. When presenting unilaterally, this flaring can mimic a range of serious pathological conditions such as osteomyelitis, osteal tumors, and traumatic injury. An improved understanding of ischiopubic synchondrosis fusion is therefore critical to avoid potential misdiagnosis. Retrospective multi-slice computed tomography pelvic scans of Australian individuals aged neonate to 24 years (n = 184) were assessed using a novel five stage morphological classification system of the maturation and fusion of the ischiopubic synchondrosis. Maturation scoring was conducted using both multiplanar formatting views and volume-rendered reconstructions in OsiriX™. Maturational stage was strongly related to age (P < 0.001) with fusion of the ischiopubic synchondrosis observed between the ages of 4 and 9 years in females and 7 and 13 years for males. The highest probability of fusion in our Queensland Australian population based on multinomial regression predictive modeling was between 7 and 10 years of age. We documented three variants of fusion: pubic and ischial outgrowths, appearance of a secondary ossification center, and a fusiform-shaped enlargement. This study provides the first predictive modeling of the timing of fusion of the ischiopubic synchondrosis using a reliable morphological classification system. The significant variation in timing and progression of fusion of the ischiopubic synchondrosis reported in this study, will aid in minimizing misdiagnosis and unnecessary treatment in children presenting with asymmetrical or delayed ischiopubic synchondrosis anomalies. Clin. Anat. 32:851-859, 2019. © 2019 Wiley Periodicals, Inc.

Un cas d’ostéochondrose ischiopubienne révélée par une « synovite aiguë transitoire de hanche » atypique

Background: Ischio-pubic Osteochondritis is characterized by an atypical ossification pattern of the ischio-pubic synchondrosis. Radiologically it may mimic stress fracture, neoplasm, osteomyelitis, or post-traumatic osteolysis. 99mTc-MDP bone scintigraphy with SPECT/CT is one of the effective tools for its diagnosis. Case presentation: A male patient, 11 years of age visited nuclear medicine department of our hospital with complaint of pain in the right hip with no history of fever, trauma or fall. There were no signs of inflammation or swelling at the site of pain. X-ray showed lytic lesion in the right inferior ischio-pubic ramus with area of lucencies. A 99mTc-methylene diphosphonate (99mTc-MDP) bone scan showed focal area of increased uptake in the right inferior ischio-pubic ramus. SPECT/CT hybrid imaging showed areas of demineralization at the edges of ischio-pubic synchondrosis with areas of sclerosis, findings compatible with Ischio-pubic osteochondritis. Patient was later treated with anti-inflammatory drugs and steroids. Conclusion: Ischio-pubic Osteochondritis is one of the differential diagnosis in children presenting with pain in the groin, hip or gluteal region and limping gait. Ample awareness of this ailment is necessary for early diagnosis and proper management, to alleviate the suffering of child.

One case that occurred osteomyelitis of ischiopubic synchondrosis

Epiphyseal growth plates developing during skeletal maturation are the most common temporary synchondroses in childhood. The fibrocartilaginous bridge between the superomedial pubic and the inferolateral ischial ossification center is defined as the ischiopubic synchondrosis (IPS). It is considered to be a physiologic developmental stage that can be recognized on conventional radiographs as a fusiform radiolucent area at the ischiopubic zone [1, 2]. The ossification of IPS begins early in childhood and is usually completed before puberty. While usually asymptomatic, the ossification process can be accompanied by pain in the groin and restriction in the movement of the hip joint [3, 4]. Although stress fractures have been described to mimic the symptomatic IPS ossification, a traumatic fracture of the IPS as a cause of hip pain has not yet specifically been reported.

Van Neck disease (VND) is a benign skeletal abnormality of children involving a hyperostosis of the ischiopubic synchondrosis (IPS) seen on radiographs. Patients typically complain of vague groin or buttock pain. Few descriptions of this disorder exist and it easily can be mistaken for other entities, particularly osteomyelitis or tumor. It is often considered a diagnosis of exclusion as laboratory values are usually normal and routine radiographic workup may be nonspecific. We present a series of patients with VND and we compare them with a similar cohort of patients with acute hematogenous ischiopubic osteomyelitis (IPOM). We also draw attention to a new magnetic resonance imaging (MRI) finding that seems to support the theory that VND results from an excessive pull of the hamstring tendon on the ischial tuberosity. All patients presenting to our institution for the evaluation of groin or buttock pain during an 8-year period (August 2001 to May 2009) were retrospectively identified. Twenty-five patients demonstrated enhancement of the ischiopubic area on MRI. Five patients were excluded for lack of sufficient laboratory data. Ten patients were diagnosed and treated with culture proven IPOM and 10 patients were diagnosed with VND and treated with observation. History, physical examination, laboratory values, plain films, and MRI were compared to identify the diagnostic differences between these 2 entities. The age range for both groups was between 4 and 12 years old. The mean age was 7 years for the VND group and 7.6 years for the IPOM group. The VND group tended to have more distinct hyperostosis of the IPS on radiographs. The factors that were characteristic of IPOM were: fever, limp, pain with rotation of the hip, elevated erythrocyte sedimentation rate, elevated C-reactive protein (CRP), and positive blood culture. MRI showed obvious myositis, abscess, and free fluid surrounding the IPS in all patients with IPOM, but not in the VND patients. Enhancement was seen in the ischial tuberosity, near the hamstring origin, in nearly all Van Neck patients; this pattern of edema may support stress reaction and callus formation as a mechanism for IPS hypertrophy. VND is a little-known entity characterized by enlargement of the IPS and should be in the differential of groin or buttock pain in children from the age of 4 to 12 years. IPOM may present similar to VND. Absence of fever, limp, pain with rotation of the hip, elevated C-reactive protein/erythrocyte sedimentation rate, and negative blood culture can help to differentiate VND from IPOM. Presence of marrow edema around the IPS and in the ischial tuberosity, along with absence of surrounding myositis, abscess, and free fluid on MRI are reliable findings that can confirm the diagnosis of VND. The absence of these characteristics can eliminate the need for admission, aspiration, or biopsy. The treatment for VND is observation and the symptoms should abate over time with expectant management. Comparative Diagnostic, Level IV.

Peripelvic infections are rare, compared with the incidence of septic hip arthritis, but are serious, requiring emergent treatment. They often are not included in differential diagnoses for patients presenting with fever, pain, inability to bear weight, elevated white blood cell count, and elevated erythrocyte sedimentation rate. Most patients are treated initially as a septic hip arthritis. Early diagnosis and treatment are crucial to outcome in peripelvic abscess. Use of MRI may help to elucidate the correct diagnosis. Previously reported peripelvic infections included obturator internus and externus, and psoas, but to the best of our knowledge, this is first case report of infection of the ischiopubic ramus synchondrosis presenting as septic arthritis.

Abstract: F-18 FDG PET/CT showed high uptake and a lucent expansile appearance at the right ischiopubic junction of a 10-year-old girl with renal cell carcinoma. Her ischiopubic synchondrosis had not shown high uptake and appeared closed 3 months earlier. A biopsy showed no evidence of metastatic tumor. The findings may be explained by a cycle of expansion, union, reopening, expansion, and repeat closure of the synchondrosis that has been described radiographically.

The enlarged ischiopubic synchondrosis is a well-known anatomic structure; however, little is known about its physiology. In early childhood, enlargement of this synchondrosis occurs bilaterally, whereas before complete ossification, it is frequently found unilaterally. In most children, the unilateral enlarged ischiopubic synchondrosis is observed in the left hemipelvis, a finding that was hitherto unexplained. During common athletic activities, increased ground reaction forces are exerted on the weight-bearing nondominant limb, which in up to 87% of the general population is the left leg. The asymmetric exertion of these forces may explain the distinct closure sequence of this temporary joint. The purpose of this study was to correlate unilateral enlarged ischiopubic synchondrosis with foot dominance. The study cohort comprised 32 children who had undergone unenhanced radiography, CT, or MRI for reasons other than bone disorders and who presented with enlarged ischiopubic synchondroses. In these children, the distribution of enlarged ischiopubic synchondrosis and foot dominance were evaluated either retrospectively (n = 11) or prospectively (n = 21). In this cohort, 78% of patients were right-footed and 22% were left-footed. Nine of the 32 children presented with unilateral enlarged ischiopubic synchondrosis (left, seven [78%] of nine; right, two [22%] of nine). All children with enlarged left ischiopubic synchondrosis were right-footed, and all children with enlarged right ischiopubic synchondrosis were left-footed. Unilateral enlarged ischiopubic synchondrosis is closely correlated with foot dominance. The asymmetric ossification pattern of the ischiopubic synchondrosis indicates delayed ossification of this anatomic structure due to asymmetrically applied mechanical forces to the nondominant limb.