The aim of this study was to evaluate the suitability of the tapered cone stem in total hip arthroplasty (THA) in patients with excessive femoral anteversion and after femoral osteotomy. We included patients who underwent THA using Wagner Cone due to proximal femur anatomical abnormalities between August 2014 and January 2019 at a single institution. We investigated implant survival time using the endpoint of dislocation and revision, and compared the prevalence of prosthetic impingements between the Wagner Cone, a tapered cone stem, and the Taperloc, a tapered wedge stem, through simulation. We also collected Oxford Hip Score (OHS), visual analogue scale (VAS) satisfaction, and VAS pain by postal survey in August 2023 and explored variables associated with those scores.Aims
Methods
Accurate cup placement in total hip arthroplasty (THA) for the patients with developmental dysplasia of the hip (DDH) is one of the challenges due to distinctive bone deformity. Robotic-arm assisted system have been developed to improve the accuracy of implant placement. This study aimed to compare the accuracy of robotic-arm assisted (Robo-THA), CT-based navigated (Navi-THA), and manual (M-THA) cup position and orientation in THA for DDH. A total of 285 patients (335 hips) including 202 M-THAs, 45 Navi-THAs, and 88 Robo-THA were analyzed. The choice of procedure followed the patient's preferences. Horizontal and vertical center of rotation (HCOR and VCOR) were measured for cup position, and radiographic inclination (RI) and anteversion (RA) were measured for cup orientation. The propensity score-matching was performed among three groups to compare the absolute error from the preoperative target position and angle. Navi-THA showed significantly smaller absolute errors than M-THA in RI (3.6° and 5.4°) and RA (3.8° and 6.0°), however, there were no significant differences between them in HCOR (2.5 mm and 3.0 mm) or VCOR (2.2 mm and 2.6 mm). In contrast, Robo-THA showed significantly smaller absolute errors of cup position than both M-THA and Navi-THA (HCOR: 1.7 mm and 2.9 mm, vs. M-THA, 1.6 mm and 2.5 mm vs. Navi-THA, VCOR:1.7 mm and 2.4 mm, vs. M-THA, 1.4 mm and 2.2 mm vs. Navi-THA). Robo-THA also showed significantly smaller absolute errors of cup orientation than both M-THA and Navi-THA (RI: 1.4° and 5.7°, vs. M-THA, 1.5° and 3.6°, vs. Navi-THA, RA: 1.9° and 5.8° vs. M-THA, 2.1° and 3.8° vs. Navi-THA). Robotic-arm assisted system showed more accurate cup position and orientation compared to manual and CT-based navigation in THA for DDH. CT-based navigation increased the accuracy of cup orientation compared to manual procedures, but not cup position.
Although periacetabular osteotomies are widely used for the treatment of symptomatic dysplastic hips, long-term surgical outcomes and patient-reported outcome measures (PROMs) are still unclear. Accordingly, we assessed hip survival and PROMs at 20 years after transpositional osteotomy of the acetabulum (TOA). A total of 172 hips in 159 patients who underwent TOA were followed up at a mean of 21.02 years (16.6 to 24.6) postoperatively. Kaplan-Meier analysis was used to assess survivorship with an endpoint of total hip arthroplasty (THA). PROMs included the visual analogue scale (VAS) Satisfaction, VAS Pain, Oxford Hip Score (OHS), and Forgotten Joint Score-12 (FJS-12). Thresholds for favourable outcomes for OHS (≥ 42) and FJS-12 (≥ 51) were obtained using the receiver operating characteristic curve with VAS Satisfaction ≥ 50 and VAS Pain < 20 as anchors.Aims
Methods
Although periacetabular osteotomies are widely used for the treatment of symptomatic acetabular dysplasia, the surgical outcomes after long term follow-up are still limited. Thus, we assessed hip survival and patient-reported outcomes (PROMs) at 20 years after the transposition osteotomy of acetabulum (TOA). Among 260 hips in 238 patients treated with TOA, 172 hips in 160 patients were evaluated at average 20.8 years, excluding patients who died or lost to follow-up. Kaplan-Meier analysis was used to assess survivorship with an end-point of THA. PROMs were evaluated using the VAS satisfaction, VAS pain, Oxford hip score (OHS), and Forgotten joint score (FJS). The thresholds of favorable outcomes of FJS and OHS were obtained using the receiver-operating characteristic curve with VAS satisfaction ≥ 50 and VAS pain < 20 as anchors. Thirty-three hips (19.2%) underwent THA at average 13.3 years after TOA. Kaplan-Meier analysis revealed hip survival rate at 20 years was 79.7%. Multivariate analysis showed the preoperative Tönnis grade significantly influenced hip survival. Survival rates with Tönnis grade 0, grade 1, and grade 2 were 93.3%, 86.7%, and 54.8% at 20 years, respectively. More than 60% of the patients showed favorable PROMs (VAS satisfaction ≥ 50, VAS pain < 20, OHS ≥ 42, FJS ≥ 51). Advanced Tönnis grade at the latest follow-up and higher BMI were significantly associated with unfavorable OHS, but not with other PROMs. This study demonstrated the durability of TOA for hips with Tönnis grade 0–1 and favorable satisfaction in majority of the patients at 20 years after surgery. Current presence of advanced osteoarthritis is associated with the lower hip function (OHS), but not necessarily associated with subjective pain and satisfaction. Higher BMI also showed a negative impact on postoperative function.
