Eccentric reductions may become concentric through femoral head ‘docking’ (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI. We reviewed 103 patients with DDH successfully treated by CR and spica casting in a single institution between January 2016 and December 2020. MRI was routinely performed immediately after CR and at the end of each cast. Using MRI, we described the labrum-acetabular cartilage complex (LACC) morphology, and measured the femoral head to triradiate cartilage distance (FTD) on the midcoronal section. A total of 13 hips with initial complete reduction (i.e. FTD < 1 mm) and ten hips with incomplete MRI follow-up were excluded. A total of 86 patients (92 hips) with a FTD > 1 mm were included in the analysis.Aims
Methods
We present our early experience of arthroscopic
reduction of the dislocated hip in very young infants with developmental
dysplasia of the hip (DDH). Eight dislocated hips, which had failed attempts at closed reduction,
were treated by arthroscopy of the hip in five children with a mean
age of 5.8 months (4 to 7). A two-portal technique was used, with
a medial sub-adductor portal for a 2.7 mm cannulated system with
a 70° arthroscope and an anterolateral portal for the instruments. Following
evaluation of the key intra-articular structures, the hypertrophic
ligamentum teres and acetabular pulvinar were resected, and a limited
release of the capsule was performed prior to reduction of the hip.
All hips were reduced by a single arthroscopic procedure, the reduction
being confirmed on MRI scan. None of the hips had an inverted labrum.
The greatest obstacle to reduction was a constriction of the capsule.
At a mean follow-up of 13.2 months (9 to 24), all eight hips remained
stable. Three developed avascular necrosis. The mean acetabular index
decreased from 35.5° (30° to 40°) pre-operatively to 23.3° (17°
to 28°). This study demonstrates that arthroscopic reduction is feasible
using two standardised portals. Longer follow-up studies are necessary
to evaluate the functional results.
