Leg Length Balance in Total Hip Arthroplasty for Patients with Unilateral Crowe Type IV Developmental Dysplasia of the Hip

Abstract

ObjectiveTo explore the leg length balance in total hip arthroplasty (THA) with shortening subtrochanteric osteotomy (SSTO) or not for unilateral Crowe type IV developmental dysplasia of the hip (DDH) through the evaluation of postoperative full‐length anteroposterior radiographs.MethodsThe postoperative radiographs of 60 patients with unilateral Crowe type IV DDH from July 2012 to May 2019 were retrospectively reviewed. All patients underwent THA using the Pinnacle Acetabular Cup system, a ceramic liner and femoral head, and the S‐ROM stem with a proximal sleeve or cone. Patients with leg length discrepancy (LLD) < 10 mm were defined as the non‐LLD group. To identify differences associated with SSTO, the group was further divided into two groups based on whether the patient underwent SSTO. A total of 48 patients (26 for SSTO and 22 for non‐SSTO) were in the non‐LLD group. There were 3 male and 45 female patients. The mean age of the patients in the non‐LLD group was 39 years. These data, including leg length, femoral length, the height of center of rotation (COR) of the hip, the depth of the sleeve or cone in the femoral medullary canal and the height of the greater trochanter, were measured.ResultsIn the non‐LLD group, the femoral lengths in both SSTO and non‐SSTO groups were significantly shorter on the operated side compared with the contralateral side, and the mean discrepancy in the SSTO group was approximately equal to the mean length of the SSTO. The mean height of the COR of the hip on the operated sides in both SSTO and non‐SSTO groups was 13.2 mm, and the contralateral sides were 15.2 and 15.5 mm, respectively. The depth of the sleeve or cone in the femoral medullary canal between SSTO and non‐SSTO groups was 21.7 and 30.6 mm, respectively. The depth of the sleeve or cone in the SSTO group was negatively correlated with the length of SSTO. The heights of the greater trochanter in the operated and contralateral sides were 5.3 and 16.6 mm in the SSTO group, and 13.2 and 17.2 mm in the non‐SSTO group, respectively.ConclusionsShortening subtrochanteric osteotomy led to femoral shortening on the operated side for patients with unilateral Crowe type IV DDH. The position of the sleeve or cone should be close to the apex of the greater trochanter to compensate the length of the SSTO. The position of the sleeve or cone without SSTO should be adjusted to make sure that the height of the greater trochanter on the operated side is close to that on the contralateral side.

Model to Predict Need for Subtrochanteric Shortening Osteotomy During Total Hip Arthroplasty for Crowe Type IV Developmental Dysplasia

“…All procedures were performed by the same senior surgeon, using a posterolateral approach, as described in our previous studies [ 14 , 15 ]. All the acetabular components were placed in their anatomical positions.…”

<p>Patient’s Perception on Leg Length Discrepancy After Total Hip Arthroplasty in Patients with Unilateral Crowe Type IV Developmental Dysplasia of the Hip</p>

“…The procedure has been described in detail in our previous studies. [10][11][12] A cementless acetabular shell that was fixed by two screws was placed at the level of the true acetabulum. If the hip was hard reduction, the shortening subtrochanteric osteotomy (SSTO) was performed.…”

Patient’s perception on leg length discrepancy after total hip arthroplasty in patients with unilateral Crowe type IV developmental dysplasia of the hip

“…All THA were performed by a single surgeon in the lateral decubitus position, with posterolateral approach. The procedure has been described in detail in our previous studies [3,11,12]. A cementless acetabular shell that was xed by two screws was placed at the level of the true acetabulum.…”

“…Leg length discrepancy (LLD) is a frequent and serious postoperative complication after total hip arthroplasty (THA) in patients with Crowe type IV developmental dysplasia of the hip (DDH) [1][2][3] and its clinical importance is due to its associated with increased incidence of gait disorders, chronic back pain, neurological sequelae and general postoperative dissatisfaction [4]. In Crowe type IV DDH patients, it is di cult to correct LLD during THA due to the preoperative high hip dislocation [5,6].…”