Conversion of Failed Reverse Total Shoulder Arthroplasty to Hemiarthroplasty: Three Cases of Instability and Three Cases of Glenoid Loosening.

Background: Glenoid loosening and postoperative instability are common causes of failed reverse total shoulder arthroplasty (RTSA). When soft-tissue problems or large glenoid bone defect interferes with reimplantation in revision RTSA, conversion to hemiarthroplasty can be considered. We present a case series of patients who underwent conversion to hemiarthroplasty due to glenoid loosening and early instability after RTSAs, along with clinical results.

Influence of Patellar Tilt Angle in Merchant View on Postoperative Range of Motion in Posterior Cruciate Ligament-Substituting Fixed-Bearing Total Knee Arthroplasty.

Background: We investigated whether the patellar tilt angle influences the maximum knee flexion after total knee arthroplasty (TKA) performed by using a posterior cruciate ligament-substituting (PS) fixed-bearing prosthesis in patients with relatively loose or tight flexion gap.

Methods: In this prospective cohort study, we followed up 169 patients for at least 2 years after TKA using PS fixed-bearing prosthesis. The patients were divided into two groups according to the flexion gap value-calculated by subtracting the thickness of the final bearing from the flexion gap measured intraoperatively under 200-cN·m force after patellar reduction and insertion of the final femoral and tibial components-into a relatively tight group (group T; 3-6.