Clinical Research Directory

Radiographic Migration Analysis of the Insignia Hip Stem

The purpose of this study is to assess the migration pattern of the Insignia hip stem using radiostereometric analysis (RSA for short) and computed tomography (CT). Only patients with degenerative joint disease requiring primary total hip replacement will be asked to participate. The other purpose is to assess if there are any differences between the gold-standard RSA-measured migration and CT-RSA-measured migration. The clinical outcomes will be measured using joint function and patient satisfaction questionnaires. Approximately thirty patients will be enrolled onto the study.

Comparison of Mesh Fixation and Non-Fixation in eTEP

Inguinal hernia surgery is one of the most frequently performed procedures among general surgery cases. As with many open surgical methods, this repair is also performed laparoscopically. Among these closed methods, the one method is laparoscopic extended total extraperitoneal repair (eTEP). The benefits of laparoscope include less postoperative pain and complications, faster recovery, reduced chronic pain, and recurrence rate. One of the recent debates regarding the laparoscopic technique is mesh fixation. Fixation of the mesh to the cooper ligament can prevent mesh migration and consequently reduce the recurrence rate. However, it has been reported that this fixation may increase postoperative pain. Several studies have reported that recurrence may be due to inadequate mesh fixation technique. In contrast, other prospective randomized studies have found relapse unrelated to mesh fixation. In the eTEP technique, dissection is performed in a larger area than in TEP. For this reason, it can be thought that the possibility of mesh displacement is higher in the eTEP procedure. The purpose of this study is to confirm this idea with a prospective study. There are studies in the literature on mesh fixation related to the total extraperitoneal repair (TEP) technique. However, there is no study on mesh detection in the eTEP technique. The aim of the study is to compare patients who underwent withmesh fixation and without mesh fixation laparoscopic eTEP repair in terms of clinical data such as mesh displacement and hernia recurrence, chronic pain, length of hospital stay, and postoperative complications.

Migration of CS vs CR Insert in TKA Using RSA

Background: The choice whether or not to preserve the posterior cruciate ligament (PCL) in total knee arthroplasty (TKA) is coupled to the us of a PCL-retaining (CR) or a condylar (CS) insert. The CS insert is anterior-lipped (AL) to prevent anterior translation of the femur on the tibia with flexion and compensate the function of the PCL. Currently both the CR and CS insert are made of highly cross-linked polyethylene (HXPLE) to theoretically reduce wear related osteolysis. However, this also might diminish the fracture toughness and crack propagation of the insert. The investigators expect that due to the high contact forces on the anterior lip of the CS insert during flexion, especially in younger and more active patients, and the lower fracture toughness of HXPLE, the CS insert insert might show more migration, wear or other damage compared to the CR insert in the long-term, which might lead to more revisions in the CS insert compared to the CR insert. To measure the migration and wear, during surgery tantalum markers will be inserted in the host bone using a marker inserter. The displacement of the prosthesis with reference to the host bone will be measured using model-based RSA. Both tantalum markers ande the inserter are already used for study purposes. However, the safety and usability are not registered before. Objective: The primary objective is to compare the migration of both the femoral and tibial component by the use of a CS insert or CR insert both made of HXPLE using model-based roentgen stereophotogrammetric analysis (mRSA). Furthermore, the safety and usability of the tantalum markers and the marker inserter will be determined. The secondary objective is to determine the influence of the type of insert on the wear, inducible displacement, survival and clinical outcomes. Study design: A randomized controlled trial Study population: Forty-four patients scheduled to undergo primary total knee replacement, aged below 70 years with an ASA-score of 1 or 2 will be needed in total, divided in two groups of 22 patients each. Intervention: One group receives an uncemented TKP with a CS insert, while the other group receives an uncemented TKP with a CR insert. Both will be placed using the MAKO-robotic arm using a kinematic balancing technique. Outcomes: Main study parameters are migration of the femoral and tibial components measured with model-based RSA software till 10 years postoperatively. Furthermore, the stability of the markers will be determined and the complications due to the markers and/or the marker inserter will be registered. The secondary parameters are wear, inducible displacement, survival, clinical outcomes and complications up to 10 years postoperatively.