Augmented-reality-assisted K-wire placement for glenoid component positioning in reversed shoulder arthroplasty: a proof-of-concept study

The accuracy of the implant’s post-operative position and orientation in reverse shoulder arthroplasty is known to play a significant role in both clinical and functional outcomes. Whilst technologies such as navigation and robotics have demonstrated superior radiological outcomes in many fields of surgery, the impact of augmented reality (AR) assistance in the operating room is still unknown. Malposition of the glenoid component in shoulder arthroplasty is known to result in implant failure and early revision surgery. The use of AR has many promising advantages, including allowing the detailed study of patient-specific anatomy without the need for invasive procedures such as arthroscopy to interrogate the joint’s articular surface. In addition, this technology has the potential to assist surgeons intraoperatively in aiding the guidance of surgical tools. It offers the prospect of increased component placement accuracy, reduced surgical procedure time, and improved radiological and functional outcomes, without recourse to the use of large navigation or robotic instruments, with their associated high overhead costs. This feasibility study describes the surgical workflow from a standardised CT protocol, via 3D reconstruction, 3D planning, and use of a commercial AR headset, to AR-assisted k-wire placement. Post-operative outcome was measured using a high-resolution laser scanner on the patient-specific 3D printed bone. In this proof-of-concept study, the discrepancy between the planned and the achieved glenoid entry point and guide-wire orientation was approximately 3 mm with a mean angulation error of 5°

Gorham-Stout syndrome (GSS) with fulminant aseptic osteonecrosis of the shoulder

We report here a case of the rare Gorham-Stout syndrome (GSS) of the humerus. GSS is a disease in the course of which spontaneous idiopathic osteolysis occurs. We describe a case of a 46-year-old business economist who suffered an inadequate trauma and within 3 weeks developed self-limited idiopathic osteolysis of the left humerus head, also affecting the rotator cuff This could be diagnosed especially on the basis of histopathological findings. Hereupon we indicated operative repair by means of inverted shoulder joint endoprosthesis

Influence of hip replacement on sagittal alignment of the lumbar spine: An EOS study

INTRODUCTION: Changes in pelvic position can influence the sagittal alignment of the lumbar spine. The restoration of hip kinematics by hip replacement thus appears to offer the possibility of correcting sagittal alignment. This preliminary retrospective study used EOS imaging to investigate the influence of total hip arthroplasty on pelvic parameters in patients with normal preoperative pelvic parameters. METHODS: Twenty patients with hip osteoarthritis undergoing total hip arthroplasty (THA) between 2011 and 2012 received unilateral THA. To evaluate the preoperative and postoperative changes of the pelvic parameters, we analyzed EOS imaging of the patients to determine pelvic incidence, sacral slope, sacral tilt, pelvic tilt, anterior pelvic plane inclination and pelvic axial rotation. Additionally, anteversion and inclination of the acetabular cup position were determined. RESULTS: No statistically significant difference was found between the preoperative and postoperative measurements of pelvic parameters, although the change in pelvic tilt approached significance. Postoperatively, respective average values of 42.6. and 22.7. were measured for inclination and anteversion of the acetabular cup position. CONCLUSION: THA did not influence pelvic position and sagittal alignment in patients with normal preoperative pelvic parameters. A subsequent study will investigate whether corrections of pelvic parameters outside the norm in patients with OA are possible with THA