Karen Rosendahl

Prevalence of radiographic findings thought to be associated with femoroacetabular impingement in a population-based cohort of 2081 healthy young adults.

PURPOSE To report the prevalence of qualitative radiographic findings for femoroacetabular impingement (FAI) and associations among them and to characterize the inter- and intraobserver variability of these interpretations. MATERIALS AND METHODS This study is part of an institutional review board-approved population-based prospective follow-up of 2081 of 4006 (participation rate, 51.9%) young adults (874 [42.0%] male participants, 1207 [58.0%] female participants; mean age, 18.6 years) who took part in a randomized hip trial on developmental dysplasia of the hip. All participants gave informed consent. Two pelvic radiographs were obtained. Pistol-grip deformity, focal femoral neck prominence, and flattening of the lateral head, all suggestive of cam-type impingement, and the posterior wall sign, excessive acetabular coverage, and crossover sign, all suggestive of pincer-type impingement, were assessed subjectively by an experienced radiologist. To assess inter- and intraobserver agreement, images from 350 examinations were read independently twice by two observers. RESULTS Cam-type deformities were seen in 868 male and 1192 female participants, respectively, as follows: pistol-grip deformity, 187 (21.5%) and 39 (3.3%); focal femoral neck prominence, 89 (10.3%) and 31 (2.6%); and flattening of the lateral femoral head, 125 (14.4%) and 74 (6.2%). Pincer-type deformities were seen in the same numbers of male and female participants, respectively, as follows: posterior wall sign, 203 (23.4%) and 131 (11.0%); and excessive acetabular coverage, 127 (14.6%) and 58 (4.9%) (all P < .001, according to sex distribution). The crossover sign was seen in 446 (51.4%) and 542 (45.5%) of the male and female participants, respectively (P = .004). There was a high degree of coexistence (odds ratio [OR] > 2) among most FAI findings. Interobserver agreement was good to very good (κ = 0.74-0.84) in rating cam- and pincer-type findings. Intraobserver agreement was moderate or good (κ = 0.49-0.80) for all findings for both observers. CONCLUSION Overall, radiographic FAI findings are quite common in a population of healthy young adults, especially in males, with a high degree of coexistence among most findings (OR > 2).

Neonatal bronchopulmonary dysplasia predicts abnormal pulmonary HRCT scans in long-term survivors of extreme preterm birth

Background: There is an increasing understanding that extreme preterm birth carries a risk of long-term pulmonary sequelae. A study was undertaken to investigate if, and in what way, neonatal factors were associated with subsequent abnormalities on pulmonary high-resolution CT (HRCT) scanning and if pulmonary function was related to these abnormalities. Methods: HRCT scanning and pulmonary function tests were performed less than 2 weeks apart in 74/86 eligible subjects (86%) born at a gestational age of ⩽28 weeks or with a birth weight of ⩽1000 g within a defined area in Western Norway in 1982–5 (n = 42) or 1991–2 (n = 32). Mean age at examination was 18 and 10 years, respectively. HRCT scans were interpreted by a paediatric radiologist blinded to the clinical data using a structured system allowing scores from 0 to 50. Results: Lung parenchymal abnormalities were found in 64 subjects (86%), the median (interquartile range) score being 3.0 (1.75–5.0) points. Prolonged neonatal requirement for oxygen treatment predicted poor outcome, and an increase of 100 days increased the average HRCT score by 3.8 points (p<0.001). There was also a positive association of the severity of pulmonary function abnormalities with the extent of HRCT abnormalities, exemplified by the relation between forced expiratory volume in 1 s and total HRCT score (β = −0.090; p<0.001). Conclusions: In area-based cohorts of long-term survivors of extremely preterm birth, prolonged neonatal requirements for oxygen treatment predicted subsequent structural abnormalities on HRCT scans and in pulmonary function, and these two outcome measures were interrelated.

The paediatric wrist revisited: redefining MR findings in healthy children

Objectives During a multicentre study on juvenile idiopathic arthritis, wide variations were observed in bone shape, signal intensity and volume of joint fluid as shown by MRI which in part appeared to be unrelated to disease activity. A study was undertaken to examine these features in a cohort of healthy children. Methods 88 children of mean age 9.8 years (range 5–15) underwent MRI imaging (T1-weighted Spin Echo and Spectral Selection Attenuated Inversion Recovery (SPAIR)) of the left wrist. The number of bony depressions, distribution and amount of joint fluid and the presence of bone marrow changes were assessed. Results Bony depressions were present in all children, increasing with age from a mean of 4.0 in children aged 4–6 years to 9.2 in those aged 12–15 years (p<0.001)). 45 of 84 children (53.6%) had a high signal on SPAIR with a corresponding low signal on T1 in at least one bone. No associations were seen between bone marrow change (present or not) and sex (p=0.827) or sports club membership (p=0.616). All children had visible joint fluid in at least one of the joints assessed. No associations were seen between the presence of joint fluid and age group, except for the radius/scaphoid and capitate-scaphoid joints and a recess lateral to the hamate. Conclusions It is important to be aware of the high prevalence of bony depressions, signal changes suggestive of bone marrow oedema and the volume of joint fluid seen in normal children. Such findings must be interpreted with care in children with suspected disease such as juvenile arthritis.

High-resolution CT of the chest in children and young adults who were born prematurely: findings in a population-based study.

OBJECTIVE The purpose of this study was to use a scoring system for high-resolution CT in the evaluation of radiologic findings in young people born extremely preterm and to examine the reproducibility of this scoring system. SUBJECTS AND METHODS High-resolution CT of the lungs was assessed in 72 children born at a gestational age of < or = 28 weeks or with a birth weight of < or = 1,000 g within a defined region in western Norway in 1982-1985 (n = 40) or in 1991-1992 (n = 32). All images were analyzed by two pediatric radiologists using a scoring system in which a total of 14 features were assessed. RESULTS Sixty-three (88%) of the subjects had abnormal findings, the most common being linear opacities (n = 52), triangular opacities (n = 42), air trapping (n = 19), and mosaic perfusion (n = 10). Right and left lungs were equally affected. There were fewer abnormalities in the younger age group (born in 1991-1992). Intraobserver agreement and interobserver agreement were moderate (weighted kappa = 0.54 and kappa = 0.52, respectively). Fifty-six of the 72 children had a clinical diagnosis of bronchopulmonary dysplasia, and the median total score and the median scores of the four most common findings were higher in the bronchopulmonary dysplasia group; however, the differences were not statistically significant. CONCLUSION High-resolution CT in young people of preterm birth revealed abnormal radiologic findings in 81.3% of the patients at age 10 years and 92.5% at age 18 years. Linear, triangular, and subpleural opacities were the most common. The reproducibility of the applied scoring system was acceptable.

Reliability of ultrasound in the early diagnosis of developmental dysplasia of the hip

The purpose of this study was to determine inter-and intra-observer agreement in assessing hip morphology and stability by ultrasound. Three groups of infants, of 206, 74 and 78 newborns respectively, were examined. Morphology was classified into four categories (normal, immature, minor dysplastic and major dysplastic) according to subjective assessment, objective measurement (of the acetabular inclination angle α) or a combination of the two. Inter- and intra-observer agreement was determined for reading of recorded ultrasound scans, and for examination (recording plus reading of the scans). Hip stability was subjectively classified as stable, unstable, dislocatable or disclocated, and inter-observer agreement was determined. There was a high degree of agreement for morphological classification based on repeated readings of recorded scans by the same observer (206 infants, κ=0.7 and 0.8 for the two observers, respectively) while the degree of agreement between observers was moderate (κ=0.5). The agreement between observers for repeated readings and recordings was moderate when based on a subjective classification (κ=0.5). Adding the α angle did not improve agreement. There was a moderate inter-observer agreement in determining hip stability (70 infants, κ=0.4). The authors concluded that a high degree of inter-and intra-observer agreement in classifying hip morphology may be obtained for the reading of recorded ultrasound scans. Inter- and intra-observer agreement in producing the scans is poorer than for reading. To obtain a high degree of inter-observer agreement in assessing hip morphology and stability in the newborn, substantial training, attention to details in the technique, and evaluation of results are necessary.

Developmental dysplasia of the hip. A population-based comparison of ultrasound and clinical findings

Clinical and ultrasound findings were compared in 3613 newborns examined for developmental dysplasia of the hip (DDH) within 48 hours of delivery. Clinical and sonographic hip stability was described as stable, borderline unstable, dislocatable or dislocated, and the morphology on ultrasound as normal, immature or dysplastic. Persistent clinical or sonographic dislocatability or dislocation. major dysplasia or minor dysplasia combined with an unstable femoral head were indications for early treatment. A total of 123 (3.4%) infants were subjected to early treatment. of which 55 (45%) fulfilled the criteria for treatment on both clinical and ultrasound examinations, 52 (42%) were treated on the basis of ultrasound findings alone, and 16 (13%) on the basis of clinical findings alone. Thirty percent of the infants with clinically dislocated or dislocatable hips were judged to have stable or just borderline unstable hips on the first clinical examination. Of 486 (13.5%) infants with sonographically immature or minor dysplastic but stable hips, 472 (97%) normalized spontaneously, while treatment was initiated in 14 (3%) of them at 1‐3 months of age because of lack of sonographic improvement. Only one infant presented with late DDH during an observation period of 3 years. Accepting sonographic dysplasia as a criterion for early splinting may result in a treatment rate which is almost twice the rate based on clinical criteria, but late dislocation may be virtually eliminated.

Developmental dysplasia of the hip

Developmental dysplasia of the hip affects 1-3% of newborns.1 2 w1-w3 A registry based study showed that it was responsible for 29% of primary hip replacements in people up to age 60 years.3 The effectiveness of screening programmes aimed at early detection varies according to their organisation, methods of ascertainment, and diagnostic criteria.1 4 5 w4 Delay in diagnosis means that more complex treatments with higher failure rates will be required, so early diagnosis and prompt, appropriate treatment are essential. We describe the diagnosis, management, and screening controversies for hip dysplasia and provide a framework for early assessment, based on the available literature, including studies with level 1 evidence. #### Summary points The term refers to a spectrum of pathology, ranging from mild acetabular dysplasia with a stable hip through more severe forms of dysplasia, often associated with neonatal hip instability, to established hip dysplasia with or without later subluxation or dislocation. The condition used to be known as congenital dislocation of the …

Congenital dislocation of the hip: a prospective study comparing ultrasound and clinical examination

Screening for congenital dislocation of the hip by standard clinical methods and ultrasound was compared prospectively in 1503 newborns (1291 girls and 212 boys). A total of 82.8% of the hips (78.8% of the infants) had well developed acetabulae, 14.5% (17.2% of the infants) were shallow (immature) and 2.7% (4.1% of the infants) were dysplastic. Within 1‐3 months 96.7% of the infants with clinically stable, but immature hips normalized, while 3.3% did not improve or worsened, and therapy was therefore initiated. Indications for treatment included dysplastic and/or clinically unstable hips, and a higher number of newborns were treated during the study period than in 1982‐85 (31.2 vs 19.7 per 1000, p= 0.0002). Thirty‐seven percent of the patients had both clinical and ultrasound findings compatible with congenital dislocation of the hip, while the decision to treat was based on clinical findings alone in 25.0% and on ultrasound findings in 38.0%. Infants born during the study period of nine months had a low incidence of late congenital dislocation of the hip compared with our earlier reported results from 1982‐85 (0.9 vs 3.5 per 1000, p= 0.012). The study demonstrated major discrepancies between clinical and ultrasound evaluation of hips in the newborn, and the role of ultrasound in the screening for congenital disclocation of the hip requires further evaluation.

Total hip replacement in young adults with hip dysplasia: age at diagnosis, previous treatment, quality of life, and validation of diagnoses reported to the Norwegian Arthroplasty Register between 1987 and 2007.

Background and purpose Dysplasia of the hip increases the risk of secondary degenerative change and subsequent total hip replacement. Here we report on age at diagnosis of dysplasia, previous treatment, and quality of life for patients born after 1967 and registered with a total hip replacement due to dysplasia in the Norwegian Arthroplasty Register. We also used the medical records to validate the diagnosis reported by the orthopedic surgeon to the register. Methods Subjects born after January 1, 1967 and registered with a primary total hip replacement in the Norwegian Arthroplasty Register during the period 1987–2007 (n = 713) were included in the study. Data on hip symptoms and quality of life (EQ-5D) were collected through questionnaires. Elaborating information was retrieved from the medical records. Results 540 of 713 patients (76%) (corresponding to 634 hips) returned the questionnaires and consented for additional information to be retrieved from their medical records. Hip dysplasia accounted for 163 of 634 hip replacements (26%), 134 of which were in females (82%). Median age at time of diagnosis was 7.8 (0–39) years: 4.4 years for females and 22 years for males. After reviewing accessible medical records, the diagnosis of hip dysplasia was confirmed in 132 of 150 hips (88%). Interpretation One quarter of hip replacements performed in patients aged 40 or younger were due to an underlying hip dysplasia, which, in most cases, was diagnosed during late childhood. The dysplasia diagnosis reported to the register was correct for 88% of the hips.

Ultrasound in the early diagnosis of congenital dislocation of the hip: The significance of hip stability versus acetabular morphology

Recent studies have suggested that ultrasound examinations may improve diagnostic accuracy in congenital dislocation of the hip, but there is differing opinion whether ultrasound diagnosis should be based on morphology or stability. Ultrasound was added to the routine clinical screening in 1503 newborns (1291 girls and 212 boys). Hip morphology was classified according to Graf (type 1–4), while sonographic stability was based on a modified Barlow maneuvre, and classified as stable, elastic deflection (normal finding), unstable (provocating a gap between the femoral head and the acetabulum) and dislocated. Among 80 morphologically dysplastic hips, 73 (91%) were sonographically unstable or dislocated, while seven dysplastic hips were stable. On the other hand, in 49% of the sonographic unstable hips (69 out of 142) the acetabulum was either normal or just physiologically immature. 38 of these hips were left untreated and normalized spontaneously. There was a close correlation between sonographically and clinically determined hip stability (gamma = 0.95). Our study shows that the majority of morphologically dysplastic hips is sonographically unstable or dislocated, but also that morphologically dysplastic hips may be stable. Morphologically normal hips showing minor sonographic instability do probably not require treatment, and thus morphology seems to be an important diagnostic criterion.