Abstract：
BACKGROUND: The clinical significance of an isolated hip click remains unclear. The rates of developmental dysplasia of the hip (DDH) in those referred for hip click vary from 0% to 28%. The purpose of this study was to evaluate the rate of DDH in patients prospectively referred for isolated hip click.
METHODS: We prospectively enrolled patients referred to a single pediatric orthopaedic center with concern for DDH secondary to isolated hip click felt by the pediatrician on examination. Patients with known sonographic abnormalities or risk factors for DDH (breech presentation or positive family history) were excluded. Ultrasounds were obtained upon initial presentation and defined as abnormal if alpha angle <60 degrees and/or femoral head coverage (FHC) <50%. Mild dysplasia, analogous to Graf IIa physiological immaturity, was defined as alpha angle 50<α<60 and/or <50% FHC in a patient <3 months age. Severe dysplasia was defined as ≤33% FHC, which has been proposed to be sonographically consistent with a hip dislocation.
RESULTS: Two hundred fifty-five children were referred for isolated hip click. One hundred eighty-nine patients (74%) had normal ultrasound whereas 66 patients (26%) had sonographic abnormalities (mean age 6.5±6.2 wk at initial ultrasound). Fifty patients (19.6%) demonstrated physiological immaturity, 3 patients (1.2%) demonstrated moderate sonographic dysplasia, and 13 patients (5.1%) had sonographic findings consistent with severe dysplasia or dislocated hip. Hips with severe dysplasia were younger than the remaining population (2.8±2.4 wk vs. 6.6±6.2 wk, P <0.001) with no difference in sex distribution ( P =0.07) or first-born birth order ( P =0.36). For those with sonographic abnormality, 18 (27%) patients were treated with Pavlik harness, 1 (2%) was treated with abduction orthosis, and the remainder (71%) were observed for resolution of physiological immaturity.
CONCLUSIONS: Infants with isolated hip click identified by their pediatrician may have higher rates of dysplasia than previously reported. We recommend screening ultrasound and/or orthopaedic referral for all infants with isolated hip click.
METHODS: Level II-prospective prognostic study.
METHODS: We prospectively enrolled patients referred to a single pediatric orthopaedic center with concern for DDH secondary to isolated hip click felt by the pediatrician on examination. Patients with known sonographic abnormalities or risk factors for DDH (breech presentation or positive family history) were excluded. Ultrasounds were obtained upon initial presentation and defined as abnormal if alpha angle <60 degrees and/or femoral head coverage (FHC) <50%. Mild dysplasia, analogous to Graf IIa physiological immaturity, was defined as alpha angle 50<α<60 and/or <50% FHC in a patient <3 months age. Severe dysplasia was defined as ≤33% FHC, which has been proposed to be sonographically consistent with a hip dislocation.
RESULTS: Two hundred fifty-five children were referred for isolated hip click. One hundred eighty-nine patients (74%) had normal ultrasound whereas 66 patients (26%) had sonographic abnormalities (mean age 6.5±6.2 wk at initial ultrasound). Fifty patients (19.6%) demonstrated physiological immaturity, 3 patients (1.2%) demonstrated moderate sonographic dysplasia, and 13 patients (5.1%) had sonographic findings consistent with severe dysplasia or dislocated hip. Hips with severe dysplasia were younger than the remaining population (2.8±2.4 wk vs. 6.6±6.2 wk, P <0.001) with no difference in sex distribution ( P =0.07) or first-born birth order ( P =0.36). For those with sonographic abnormality, 18 (27%) patients were treated with Pavlik harness, 1 (2%) was treated with abduction orthosis, and the remainder (71%) were observed for resolution of physiological immaturity.
CONCLUSIONS: Infants with isolated hip click identified by their pediatrician may have higher rates of dysplasia than previously reported. We recommend screening ultrasound and/or orthopaedic referral for all infants with isolated hip click.
METHODS: Level II-prospective prognostic study.
摘要：
背景：孤立的髋关节点击的临床意义尚不清楚。在髋关节点击中，髋关节发育异常（DDH）的发生率从0％到28％不等。这项研究的目的是评估前瞻性转诊为孤立性髋关节点击的患者中DDH的发生率。
方法：我们前瞻性招募了转诊到单个儿科骨科中心的患者，这些患者担心儿科医生在检查时感觉到的孤立性髋关节点击继发DDH。排除具有已知超声异常或DDH危险因素（臀位表现或阳性家族史）的患者。在初次出现时获得超声,并且如果α角<60度和/或股骨头覆盖(FHC)<50%则定义为异常。轻度发育不良,类似于GrafIIa生理不成熟，定义为α角50<α<60和/或<50%FHC患者<3个月龄。重度发育不良定义为≤33%FHC，已提出超声检查与髋关节脱位一致。
结果：二百五十五名儿童因孤立的髋关节点击而被转诊。一百八十九名患者（74％）的超声检查正常，而66名患者（26％）的超声检查异常（初次超声时的平均年龄为6.5±6.2wk）。50例患者（19.6%）表现出生理不成熟，3例患者（1.2%）表现为中度超声发育不良，13例患者(5.1%)的超声检查结果与严重的发育不良或髋关节脱位一致.严重发育不良的髋关节比其余人群年轻（2.8±2.4wkvs.6.6±6.2周，P<0.001），性别分布（P=0.07）或第一胎出生顺序（P=0.36）没有差异。对于那些有超声异常的人，18例（27%）患者接受了Pavlik线束治疗，1（2%）采用外展矫形器治疗，其余（71％）观察到生理不成熟的解决。
结论：儿科医生确定的孤立髋关节点击的婴儿发育异常的发生率可能高于先前报道的。我们建议筛查超声和/或骨科转诊为所有婴儿孤立的髋关节点击。
方法：II级前瞻性预后研究。
方法：我们前瞻性招募了转诊到单个儿科骨科中心的患者，这些患者担心儿科医生在检查时感觉到的孤立性髋关节点击继发DDH。排除具有已知超声异常或DDH危险因素（臀位表现或阳性家族史）的患者。在初次出现时获得超声,并且如果α角<60度和/或股骨头覆盖(FHC)<50%则定义为异常。轻度发育不良,类似于GrafIIa生理不成熟，定义为α角50<α<60和/或<50%FHC患者<3个月龄。重度发育不良定义为≤33%FHC，已提出超声检查与髋关节脱位一致。
结果：二百五十五名儿童因孤立的髋关节点击而被转诊。一百八十九名患者（74％）的超声检查正常，而66名患者（26％）的超声检查异常（初次超声时的平均年龄为6.5±6.2wk）。50例患者（19.6%）表现出生理不成熟，3例患者（1.2%）表现为中度超声发育不良，13例患者(5.1%)的超声检查结果与严重的发育不良或髋关节脱位一致.严重发育不良的髋关节比其余人群年轻（2.8±2.4wkvs.6.6±6.2周，P<0.001），性别分布（P=0.07）或第一胎出生顺序（P=0.36）没有差异。对于那些有超声异常的人，18例（27%）患者接受了Pavlik线束治疗，1（2%）采用外展矫形器治疗，其余（71％）观察到生理不成熟的解决。
结论：儿科医生确定的孤立髋关节点击的婴儿发育异常的发生率可能高于先前报道的。我们建议筛查超声和/或骨科转诊为所有婴儿孤立的髋关节点击。
方法：II级前瞻性预后研究。
