Meyer Dysplasia in the Differential Diagnosis of Hip Disease in Young Children

ARTICLE Meyer Dysplasia in the Differential Diagnosis of Hip Disease in Young Children

Liora Harel, MD; Liora Kornreich, MD; Shai Ashkenazi, MD, MSc; Avinoam Rachmel, MD; Boaz Karmazyn, MD; Jacob Amir, MD

Objectives: To describe a rare developmental disorder Results: Two of the 5 patients were initially diagnosed of the femoral capital epiphysis in infants and children as having osteomyelitis and 3 as having Perthes disease. that is often misdiagnosed and to suggest an evaluation The diagnosis of Meyer dysplasia was confirmed by plain protocol to differentiate it from other hip problems. film of the pelvis, a negative bone scan, or normal bone marrow findings on magnetic resonance imaging. The Design: Case series. limping resolved without treatment in all patients within 1 to 3 weeks. Setting: Tertiary care center. Conclusions: Meyer dysplasia is a benign condition that Subjects: Five consecutive patients referred for evalu- should be included in the differential diagnosis of hip dis- ation of acute onset of limping between January 1990 and ease in infants and children. Awareness of this condi- December 1997. tion may prevent unnecessary hospitalization and treatment. Intervention: All clinical and imaging data were col- lected. Arch Pediatr Adolesc Med. 1999;153:942-945

5 patients. The 5 children included 4 males Editor’s Note: Keep this in mind next time you see a limping and 1 female aged 9 to 48 months. All pre- toddler or preschooler. sented with acute onset of limping of 2 to Catherine D. DeAngelis, MD 30 days’ duration. Patient 3 was being observed by a pediatric endocrinologist for short stature, and patient 4 had a family EYER dysplasia is a history of congenital dislocation of the hip symptomless develop- and Perthes disease. Otherwise, the his- mental disorder of the tories were unremarkable. hip manifested by de- Physical examination revealed a delayed, irregular ossifi- creased range of motion of the hip joint cationM of the femoral epiphysial nucleus.1 in 3 of the 5 patients; in 1 (patient 2), it The dysplasia is noted during the second was accompanied by fever. Acute-phase re- year of life and usually disappears by the actants (high erythrocyte sedimentation end of the sixth year without treatment.2 rate, high white blood cell count) were This rare condition may easily be mis- found in 2 patients (patients 1 and 2). Hip taken for other hip problems, leading to radiographs revealed various epiphysial unnecessary diagnostic procedures and changes compatible with Meyer dyspla- treatments. sia in all patients, 3 of whom had bilat- We describe 5 children who were ul- eral involvement (Figure 1). From the Department of timately diagnosed as having Meyer dys- The initial diagnosis in patients 1 and Pediatrics (Drs Harel, plasia and suggest guidelines for the evalu- 2 was acute osteomyelitis, based on the Ashkenazi, Rachmel, and Amir) ation of this condition based on our clinical presentation and the presence of and Imaging Department findings and a review of the literature. an elevated sedimentation rate with leu- (Drs Kornreich and Karmazyn), Schneider kocytosis and radiolucent lesions of the Children’s Medical Center of RESULTS femoral head. However, the normal find- Israel, Petah Tiqva, and Sackler ings on bone scan ruled out this possibil- Faculty of Medicine, Tel Aviv Table 1 presents clinical findings and ity and supported the diagnosis of Meyer University, Tel Aviv, Israel. Table 2 presents imaging findings in the dysplasia.

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©1999 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 10/01/2021 COMMENT PATIENTS AND METHODS Pedersen3 and Meyer2 were the first to describe a subgroup of patients with Perthes disease who showed a Five consecutive patients referred to our tertiary care distinct radiological and clinical picture found rarely center between January 1990 and December 1997 for among the clinical conditions affecting the hip joint in acute onset of limping were evaluated clinically and childhood. Meyer estimated that this subgroup by imaging studies. accounted for 10% of all patients with Perthes disease and was characterized by a male predominance and young age (Ͻ5 years). He reported that this dysplasia is noted during the second year of life and usually disappears by the end of the sixth year. It is more often bilat- The 3 other patients (patients 3, 4, and 5) were first eral than typical Perthes disease (42% vs 7%) and has a suspected to have Perthes disease, based on the clinical higher familial frequency of other hip diseases such as presentation, lack of signs of infection, and the pres- congenital dislocation and Perthes disease.2 Meyer ence of epiphysial changes on the hip radiographs. Again, traced the pathogenesis to circulatory disturbances that normal bone scan findings excluded this diagnosis. Be- caused delayed, irregular ossification. Other authors cause of a family history of Perthes disease in patient 4, have attributed the dysplasia to congenital focal hypo- magnetic resonance imaging was performed, revealing plasia of the femoral epiphysis.4 multiple centers of ossification of the femoral heads. The The possibility that we are dealing with a physi- normal bone marrow intensity in all sequences ruled out ologic variant of ossification of the femoral head cannot edema and ischemia and confirmed the diagnosis of Meyer be ruled out in those who completely recover with nor- dysplasia (Figure 2). mal epiphysial shape and size. In all patients, the limping resolved without treat- Radiologically, affected patients show a marked de- ment within 1 to 3 weeks. Bone survey did not dis- lay in the development of the femoral epiphysial nucleus close epiphysial dysplasias in other bones in any of the and its pathological appearance at a later date. Matura- children. Results of thyroid function tests were nor- tion is retarded in other parts of the skeleton as well.1 In mal. Bone age (by Greulich Pyle) was retarded in all Meyer dysplasia, ossification of the femoral head does not patients. usually set in until 2 years of age. The ossification cen-

Table 1. Clinical Findings in Meyer Dysplasia

Laboratory Findings* Patient No./ Clinical Maximal Physical Initial Initial Sex/Age, mo Presentation Temperature Findings ESR, mm/h WBC, ؋109/L Diagnosis Treatment 1/F/9 Guarding of left leg Normal Limited internal rotation 60 15 Osteomyelitis Cefuroxime of left hip joint 2/M/24 Limping in left leg 39.5° C Tonsillitis, limited internal 62 26 Osteomyelitis, Cefuroxime rotation of left hip joint tonsillitis 3/M/48 Limping, waddling gait Normal Normal 25 8.8 Perthes disease None 4/M/30 Limping in left leg Normal Limited internal rotation 25 10 Perthes disease None of left hip joint 5/M/36 Limping Normal Normal 11 Not done Perthes disease None

*ESR indicates erythrocyte sedimentation rate; WBC, white blood cell count. Cefuroxime was given as cefuroxime sodium.

Table 2. Imaging Findings of the Hip Joints in Meyer Dysplasia

Patient Affected Magnetic Resonance No. Side x-Ray Film Bone Scan Ultrasound Imaging 1 Left Small, irregular epiphysis Normal Not done Not done with radiolucent lesion 2 Left Flattening, irregularity, Normal Fluid within Not done sclerosis, and joint radiolucent foci of femoral head 3 Bilateral Bilateral dysplastic changes Normal Not done Not done of femoral heads 4 Bilateral Bilateral small and irregular Normal Normal Multiple centers of ossification femoral heads of femoral heads (with normal bone marrow intensity) 5 Bilateral Bilateral fragmentation of Normal Not done Not done femoral heads

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Figure 1. Anteroposterior view of hip joint, demonstrating the various appearances of Meyer dysplasia. A, Patient 1, demonstrating radiolucent defect in the femoral head. B, Patient 2, showing flattening, sclerosis, and a radiolucent focus in the femoral head. C, Patient 4, demonstrating fragmentation of the femoral head.

lateral involvement may have a mild inconsistent waddling gait. Pain, limping, or limitation of movement are rarely observed and are usually transient.4 As healing is complete, Meyer dysplasia needs no treatment. Patients show continuous improvement with steady unification and growth of the epiphysis,1 usually over a 3-year period.2 The final outcome is a normal hemi- spherical shape and size of the femoral head,5 although some have reported diminished height.1,4 Function is prob- ably normal. Nevertheless, biomechanically induced de- generative joint changes may be anticipated in adult- hood in those with smaller femoral heads. In Perthes disease, by contrast, the natural course is associated with increased fragmentation that may result in permanent de- Figure 2. Patient 4. Magnetic resonance imaging scan, T2-weighted coronal 1 cut of the hip joints, demonstrating multiple centers of ossification of the formity of the femoral head if left untreated. However, femoral heads. The bone marrow shows normal signal intensity. in children younger than 5 years, the disease is quite benign and usually requires no intervention. ter, instead of the normal single unit, appears as a small The results of a recent prospective, clinical, and ra- epiphysial nucleus composed of multiple independent diological study of 18 children with Meyer dysplasia4 have bony foci. These foci gradually grow, coalesce, and fi- confirmed most of Meyer’s observations. Half the cases nally fuse into a single center.1 A small, single ossifica- were bilateral and boys were affected 5 times more often tion center with a cortical defect on the articular surface than girls. The imaging studies showed a delayed ap- has also been described.4 pearance of the ossification centers, with complete heal- Magnetic resonance imaging shows multiple cen- ing by an average age of 51⁄2 years, except for a slight loss ters of ossification of the femoral head, with a normal sig- in epiphysial height. Most of the patients were asymp- nal intensity in all sequences and reduced height of the tomatic. Although 6 (20%) of Meyer’s 30 patients showed cartilaginous epiphysis.4,5 Normal findings of bone scan- a shift from the benign course of dysplasia to Perthes dis- ning are typical for Meyer dysplasia.6 ease,2 no cases of Perthes disease were observed in this The differential diagnosis consists mainly of Per- study.4 This was also true for another case of bilateral fem- thes disease, which is characterized by both abnormal bone oral dysplasia, which had a favorable natural course.8 scan findings and bone marrow signals in the femoral head Wedescribed5patientswithMeyerdysplasia,2ofwhom on magnetic resonance imaging. Uniform massive con- were initially misdiagnosed as having osteomyelitis and 3 densation on hip radiographs in Perthes disease is an- of whom were thought to have Perthes disease. The diag- other feature that distinguishes it from Meyer dysplasia, nosis of Meyer dysplasia in our patients was confirmed by and that does not require expensive imaging tech- the normal bone scan findings, normal bone marrow sig- niques. However, this finding is usually a late sign and nal on magnetic resonance imaging, and complete resolu- therefore not helpful in the early stages. Whenever bi- tion of the limping. Since all our patients had been asymp- lateral changes are present, multiple epiphysial dyspla- tomatic in the past, we assume that the acute onset of limp- sia and hypothyroidism should be excluded.7 ing may have been due to an acute event, such as toxic Despite the prominent radiological findings, clini- synovitis, unrelated to Meyer dysplasia. The elevation of the cal signs are usually mild or absent, and the lesions are sedimentation rate in patients 1 and 2 may be attributed to usually discovered incidentally.1,2 Some patients with bi- an intercurrent infection that resolved without treatment.

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©1999 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 10/01/2021 Once diagnosed, these patients should be followed REFERENCES up both clinically and radiographically (with plain films) by the pediatric orthopedic surgeon. If there is not clinical deterioration (limping, limited joint movement), hip 1. Caffey J. Pediatric X-ray Diagnosis. Chicago, Ill: Yearbook Medical Publishers Inc; 1978:1372-1375. radiographs should be performed once a year until reso- 2. Meyer J. Dysplasia epiphysealis capitis femoris: a clinical-radiological syn- lution is noted. drome and its relationship to Legg-Calve´-Perthes disease. Acta Orthop Scand. In conclusion, Meyer dysplasia is a rare condition 1964;34:183-197. with a benign clinical course that may mimic other, more 3. Pedersen EK. Dysplasia epiphysealis capitis femoris [abstract]. J Bone Joint Surg Br. 1960;42:663. severe hip diseases. A greater awareness of this condi- 4. Khermosh O, Weintroub S. Dysplasia epiphysealis capitis femoris: Meyer’s dys- tion would prevent unnecessary hospitalization and treat- plasia. J Bone Joint Surg Br. 1991;73:621-625. ment and allay parental fears regarding the prognosis. 5. Resnick D, Sik Kang H. Internal Derangement of Joints. Philadelphia, Pa: WB Saunders Co; 1997:538. Accepted for publication February 8, 1999. 6. Bensahel H, Bok B. Apport de la scintigraphie a` la pathologie non infectieuse de la hanche de l’enfant. Arch Fr Pediatr. 1979;36:1040-1045. Corresponding author: Liora Harel, MD, Department 7. Spranger J. The epiphyseal dysplasias. Clin Orthop Related Res. 1976;114:46-58. of Pediatrics C, Schneider Children’s Medical Center of Is- 8. Emery L, Timmermans J, Leroy JG. Dysplasia epiphysealis capitis femoris? a rael, Petah Tiqva 49202, Israel. longitudinal observation. Eur J Pediatr. 1983;140:345-347.

Correction

Error and Omission in Text. In the article by Strauss titled “Self-reported Weight Status and Dieting in a Cross-sectional Sample of Young Adolescents: National Health and Nutrition Examination Survey III,” published in the July issue of the ARCHIVES (1999;153:741-747), an error and an omission appeared in the text. On page 742, in the “Sample” subsection of the “Subjects and Methods” section, the fourth sentence should have read as follows: “Of the children en- rolled, 1097 (56.8%) were white, 743 (38.5%) were black, and 92 (4.8%) were other.” Also, on that same page in the “Statistics” subsection of the “Subjects and Methods” section, a new sentence should have been inserted after the second sentence and read as follows: “Whites and Hispanics were grouped to- gether because of sample size limitations and herein are identified as ‘white.’ ”

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