The value of femoral head coverage in the follow-up of infants with developmental dysplasia of the hip

Abstract

Objective To discuss the value of femoral head coverage (FHC) in the follow-up of infants with developmental dysplasia of the hip(DDH). Methods Two hundred and seventeen DDH infants(434 hips) diagnosed by clinical examination and ultrasonography were chosed as treatment group, and then received the brace treatment and followed up with ultrasonography. Four hundred and sixteen infants(832 hips) with normal hips diagnosed by clinical examination and ultrasonography were chosed as control group. The ultrasonographic examination included Graf method and FHC measurement. The infants in the treatment group were followed up with ultrasonography examination up to the age of 6 months. Results The FHC in the control group was (59.69±4.36)%. In the treatment group, 302 hips were diagnosed to be DDH.Among them, 36 hips were Graf type Ⅱa, 132 hips were Graf type Ⅱb, 69 hips were Graf type Ⅱc, 8 hips were Graf type D, 41 hips were Graf type Ⅲ, and 16 hips were Graf type Ⅳ. The FHC of these hips were (51.33±5.18)%, (53.07±3.94)%, (44.52±5.32)%, (38.70±5.85)%, (27.23±6.82)% and 0, respectively. After treatment, 222 hips became Graf type Ⅰ, 49 hips were improved, and their FHC increased. Twenty-eight hips were not significantly improved after treatment, but the FHC of most hips (including 14 hips of type Ⅱb, 3 hips of Ⅱc and 4 hips of type Ⅲ) increased. Three hips of Graf type Ⅲ aggravated to Graf type Ⅳ, and the FHC decreased to 0. Conclusions The FHC has important value in the follow-up of infants with DDH. Key words: Ultrasonography; Developmental dysplasia of the hip; Femoral head coverage; Infant; Follow-up