The aim of this study was to evaluate the reliability and validity of a patient-specific algorithm which we developed for predicting changes in sagittal pelvic tilt after total hip arthroplasty (THA). This retrospective study included 143 patients who underwent 171 THAs between April 2019 and October 2020 and had full-body lateral radiographs preoperatively and at one year postoperatively. We measured the pelvic incidence (PI), the sagittal vertical axis (SVA), pelvic tilt, sacral slope (SS), lumbar lordosis (LL), and thoracic kyphosis to classify patients into types A, B1, B2, B3, and C. The change of pelvic tilt was predicted according to the normal range of SVA (0 mm to 50 mm) for types A, B1, B2, and B3, and based on the absolute value of one-third of the PI-LL mismatch for type C patients. The reliability of the classification of the patients and the prediction of the change of pelvic tilt were assessed using kappa values and intraclass correlation coefficients (ICCs), respectively. Validity was assessed using the overall mean error and mean absolute error (MAE) for the prediction of the change of pelvic tilt.Aims
Methods
With the approval of our institute, we reviewed all the robot-assisted hip revision during October 2019 and August 2021. MAKO joint arthroplasty system was used to perform the hip revision surgery. Seventy-one robot-assisted hip revision cases were included. Cup revisions were carried out in 68 patients while stem revisions were also carried out in 68 patients. Three types of registration techniques (extra acetabular bone surface based, liner based, metal shell based or cage surface based) on the acetabular side. The extra acetabular bone surface was the commonest used for registration (48/70, 68.6%, mean accuracy 0.37mm), followed by liner surface (11/70, 15.7%, mean accuracy 0.36mm), acetabulum cup (10/70, 14.3%, mean accuracy 0.37mm), and cage surface (1/70, 1.4%, accuracy 0.40mm). We succeeded cup registration and robotic arm guided cup insertion in all the cases. The average cup inclination and anteversion after revision were 40.87°±4.39° and 13.87°±4.24°, respectively. Cups in 62 cases (62/68, 91.2%) were within the Lewinnek safe zone while in 55 cases (55/68, 80.9%) were within the Callanan safe zone. The Mako robot-assisted system could bring favorable cup reconstruction in hip revision with acceptable surgical time and blood loss. Accurate registration could be achieved by different methods.
Developmental dysplasia of the hip (DDH) is a complex musculoskeletal disease that occurs mostly in children. This study aimed to investigate the molecular changes in the hip joint capsule of patients with DDH. High-throughput sequencing was used to identify genes that were differentially expressed in hip joint capsules between healthy controls and DDH patients. Biological assays including cell cycle, viability, apoptosis, immunofluorescence, reverse transcription polymerase chain reaction (RT-PCR), and western blotting were performed to determine the roles of the differentially expressed genes in DDH pathology.Aims
Methods
Vancouver type B periprosthetic femoral fractures (PFF) are challenging complications after total hip arthroplasty (THA), and some treatment controversies remain. The objectives of this study were: to evaluate the short-to-mid-term clinical outcomes after treatment of Vancouver type B PFF and to compare postoperative outcome in subgroups according to classifications and treatments; to report the clinical outcomes after conservative treatment; and to identify risk factors for postoperative complications in Vancouver type B PFF. A total of 97 consecutive PPFs (49 males and 48 females) were included with a mean age of 66 years (standard deviation (SD) 14.9). Of these, 86 patients were treated with surgery and 11 were treated conservatively. All living patients had a minimum two-year follow-up. Patient demographics details, fracture healing, functional scores, and complications were assessed. Clinical outcomes between internal fixation and revisions in patients with or without a stable femoral component were compared. Conservatively treated PPFs were evaluated in terms of mortality and healing status. A logistic regression analysis was performed to identify risk factors for complications.Aims
Methods
Failed ingrowth and subsequent separation of revision acetabular components from the inferior hemi-pelvis constitutes a primary mode of failure in revision total hip arthroplasty (THA). Few studies have highlighted other techniques than multiple screws and an ischial flange or hook of cages to reinforce the inferior fixation of the acetabular components, nor did any authors report the use of porous metal augments in the ischium and/or pubis to reinforce inferior fixation of the acetabular cup. The aims of this study were to introduce the concept of inferior extended fixation into the ischium and/or pubis during revision total hip arthroplasty, and to answer the following questions: (1) what are early clinical outcomes using inferior extended fixation and (2) what are the radiographic outcomes of hips revised with inferior extended fixation? Patients who underwent revision THA utilizing the surgical technique of inferior extended fixation with porous metal augments secured in the ischium and/or pubis in a single institution from 2014 to 2016 were reviewed. Twenty-four patients were initially identified, and 16 patients were included based on the criteria of minimum 18 months clinical and radiographic follow-up. The median HHS, as well as the SF-12 physical and mental components improved significantly at the latest follow-up (p<0.001). The WOMAC global score decreased significantly at the latest follow-up (p<0.001). All constructs were considered to have obtained bone ingrowth fixation. Early follow-up of patients reconstructed with porous metal augments using the inferior extended fixation surgical technique demonstrated satisfactory clinical outcomes, restoration of the center of rotation and adequate biological fixation.
