Zeitschrift für Hämatologie und thromboembolische Erkrankungen
Offener Zugang

Abstrakt

The Validity of Certain Clinical Sign and Risk Factors in Relation to the Results of Ultrasound Examination of the Hip in Static and Dynamic Modalities

Nayyef MM, Ahmed HG and Aljalabi YSG

During the period from January 2001 to March 2002, one hundred infants below 6 months of age (62 females and 38 males) attending orthopedic outpatient unit in Saddam General Hospital in Mosul with inconclusive clinical diagnosis of developmental dysplasia of the hip (DDH) were included in this study. The study aimed at evaluating the validity of certain clinical signs (including unequal thigh and inguinal skin folds, hip click and limited abduction) and risk factors (including sex, cesarean section, breech presentation, family history, birth order or parity of the mother and associated foot deformities) by relating them to the results of ultrasound examination of the hip in the static and dynamic modalities. The clinical signs and risk factors were appraised using within-group comparison statistical analysis and considering ultrasound as the reference standard for diagnosis of DDH in this age group. Abnormal hips were more frequently detected in females (female to male ratio 1.5-1) but males tended to have more severe pathology (38% of male had dislocatable hips compared to 19 % of females) especially when associated with foot deformities. Breech presentation was more frequently associated with subnormal hips (type IIa/b in 47% of breech presenting versus 29.5% of head presenting infants) but did not significantly affect the severity of DDH. Cesarean section had no significant effect on frequency and severity of DDH when considered in isolation. The first born child was clearly more at risk of having DDH and their hips represented 42% of the total abnormal hips. Foot anomalies increased the possibility of DDH both quantitatively and qualitatively (P value 0.001 and OR 3.24). Positive family history of DDH was the most significant risk factor encountered in the study population (P value 0.01 and 3.5). Unequal skin folds represented a sensitive indicator of hip abnormality (sensitivity 82%) but had low specificity (15.8%). Yet, this sign should be regarded as an indispensable adjunct to other criteria for the diagnosis of DDH. Hip click had moderate sensitivity and specificity but a high positive predictive value (71) denoting its value in detecting true positive cases of DDH. Limited abduction was the most specific sign in DDH (71.2) and hence, the most valuable clinical sign. Depending on the foregoing clinical criteria, the diagnostic accuracy in this age group in the absence of frank sings of DDH (positive Barlow and Ortolani tests and severe limitation of abduction) was 63%.