Treatment of infectious hip arthritis with optimized articulating medullary-sparing spacer

Abstract

Objective To explore the clinical effects of optimized articulating medullary-sparing spacer in the treatment of infectious hip arthritis. Methods From June 2010 to June 2016, the clinical data of 15 patients with infectious hip arthritis who were treated by modified articulating medullary-sparing spacer were analyzed retrospectively. There were 6 males and 9 fe-males with the average age of 49.6±9.6 years old (range, 32-61 years). 8 cases were primary hip infections and 7 cases were sec-ondary hip joint infections. After complete debridement in the first phase of surgery, the modified articulating medullary-sparing spacers were fabricated and installed using the larger diameter and angled Steinmann pins as the endoskeleton and the femoral head spacers made by hubbing. Two-stage THA revision for each patient was conducted after infection controlled. To evaluate the clinical results, the infection and treatment condition of every patient were collected at preoperative, interim period and latest fel-low-up. The spacer status in interim period and prosthesis status after two-stage THA revision were observed. And Harris hip score system was used to evaluate the hip joint function in different stages. Results All patients were cured with mean follow-up time of 40.9±10.8 months (range, 28-62 months). During the interim period, spacer dislocation was observed in a case, which was suc-cessfully treated by manual reduction under general anesthesia. In other cases, the affected limbs maintained good function and partial weight bearing. After the second-stage THA, no prosthesis loose, dislocation, fracture, deep vein thrombosis and injury of major vessels or nerves were observed. The clinical symptoms and hip joint function of all cases were significantly improved. The Harris hip score was improved from 33.7±6.9 preoperatively to 59.5±8.5 in interim period and 90.8±4.4 at the latest fellow-up, and the difference was statistically significant among three stages. Conclusion The larger diameter and angled Steinmann pins as the endoskeleton, combined with the femoral head spacers made by hubbing, effectively enhanced the mechanical strength of the artic-ulating medullary-sparing spacers. The optimized spacers provided effective treatment of infectious hip arthritis, while allowing good function and partial weight-bearing during the interim period. Key words: Hip joint; Infection; Arthroplasty, replacement, hip