First hip hemiarthroplasty in a Göttingen Minipig; surgical and post-mortem protocol.

BACKGROUND: Prosthetic joint infections (PJI) are recalcitrant, hard-to-treat infections and severe complications of joint arthroplasty. Therefore, there is a need to develop new effective treatment strategies, and animal models of high clinical relevance are needed. This study aimed to develop a detailed surgical protocol for hip hemiarthroplasty in Göttingen minipigs and a thorough post-mortem sampling protocol to pave the way for creating a minipig PJI model. METHODS: Three adult female Göttingen minipigs underwent surgery with insertion of a hip hemiarthroplasty, using the anterior approach to the hip joint. After surgery the minipigs were followed closely with daily clinical evaluation and gait scoring. Comprehensive post-mortem analyses were performed with evaluation of macroscopic lesions, microbiology, synovial fluid analysis and histology. RESULTS: The study resulted in the first Göttingen minipig with hip hemiarthroplasty and identified several points of awareness when inserting a hip prosthesis in minipigs, especially the high risk of joint dislocation. A spontaneous PJI occurred in one of the minipigs, revealing an impaired ability of the immune cells to reach the bacteria at the bone-prosthesis interface. CONCLUSION: The present study provides a detailed description of surgical technique and post-mortem sampling and validates the suitability of the hip hemiarthroplasty minipig model for future experimental modeling of PJI.

Noticeable Variations in the Educational Exposure During Residency in Danish Orthopedic Departments.

OBJECTIVE: The objective of the study was to examine the educational exposure during residency in Danish orthopedic departments. DESIGN: Questionnaire-based cross-sectional study. SETTING: Data were gathered from January 1, 2014 to April 30, 2014 through a nationwide web-based questionnaire containing 15 questions within the areas of workload, surgical procedures, outpatient clinic, and research activities. The residents targeted worked at small-to-large hospitals and in tertiary care centers. PARTICIPANTS: Every resident in Denmark (n = 163) with at least 3 active months at a department was included. Questionnaires with less than 80% completion were excluded. In total, 152 entries were registered. Among those, 27 did not meet the inclusion criteria and 29 were excluded, leaving 96 participants, representing 22 of 26 departments, for further analysis. RESULTS: The average number of operative procedures as primary surgeon was 16 (range: 8-35) per month. In all, 18 of 22 (81%) departments offered the possibility to participate in research facilitated by the department and 38 of 96 (40%) worked for free (an average of 10h a month [range: 3-60]) to increase the amount of surgical procedures. CONCLUSIONS: A large variation in the educational exposure was found among the Danish orthopedic departments. Numbers indicate that Danish residents, compared with their US counterparts, operate considerably less during residency. Most residents work overtime and many of them work for free to participate in more surgical procedures.