Iranian Journal of Orthopedic Surgery

Abstract Background: Severe acetabular bone loss following total hip arthroplasty (THA) presents a complex reconstructive challenge. Traditional classification systems, such as Paprosky, may not fully capture the morphology of defects in the most extreme cases. Additionally, previous revision plans could not safely manage such cases.
Case Presentation: A 71-year-old man presented with pain and instability four years after a primary THA. Imaging revealed a massive acetabular defect with extensive osteolysis and metallosis, including complete loss of the posterior column, medial wall, posterior wall, inferior rim, and ischium, and only the anterior wall and column remained intact. The acetabular cup had also protruded into the pelvic cavity, approaching the bladder, and had migrated centrally. While the defect resembled a Paprosky type IIC pattern, it was markedly more severe and did not fit existing classifications. A complex two-stage reconstructive surgery was performed, involving elevation of the hip center by 2.5 to 3 cm and compensation for limb shortening through femoral stem lengthening using a long-stem prosthesis. After 2-step revision surgery, the patient experienced prosthetic dislocation, necessitating a third surgery. During this procedure, a bipolar cup was manually drilled to allow bone cement to pass through the holes for improved fixation. Additionally, bone cement was applied over the screw heads (positioned superior to the cup) to construct a scaffold that enhanced implant stability and reduced the risk of dislocation.
Discussion: This case may represent a novel subtype of acetabular bone defect not encompassed by current classification systems. Furthermore, the innovative approach of penetrating a bipolar cup and using cement augmentation over a screw framework presents a potential new strategy for achieving stable fixation in cases of severe bone loss.
Conclusion: This case underscores the need for updated classification systems to account for atypical acetabular defect patterns and demonstrates a novel fixation technique that may improve outcomes in revision THA involving extensive bone loss.

Abstract Abstract
Introduction: Postoperative bleeding is a major concern in total knee arthroplasty (TKA), often leading to complications such as anemia and increased demand for blood transfusion. Tranexamic acid (TXA), an antifibrinolytic agent, is used intravenously and topically to reduce surgical blood loss. This study aimed to compare the efficacy of three administration methods of TXA (intravenous, topical, and combined) in reducing bleeding among Iranian patients.
Materials & Methods: This double-blind randomized clinical trial (RCT) was conducted on 135 patients undergoing TKA, between February 2021 and June 2021. Patients were randomly assigned to three groups of 45 each: intravenous, topical, and combined. Demographic data, postoperative drainage volume, hemoglobin changes, and other clinical variables were analyzed using SPSS software.
Results & Discussion: The combined TXA group showed a statistically significant reduction in intraoperative bleeding (524.0 ± 150.5 mL) compared to the intravenous (665.6 ± 136.3 mL) and topical (740.2 ± 141.5 mL) groups (p<0.05). This group also experienced a smaller postoperative drop in hemoglobin. No significant differences were observed among the groups in terms of edema or knee circumference (p>0.05).
Conclusion: The combined administration of intravenous and topical TXA was more effective in reducing postoperative drainage volume and hemoglobin drop, compared to either method alone. These findings support the superiority of the combined approach and highlight the importance of TXA use in managing bleeding in orthopedic surgeries.