Delayed diagnosis is a well-known complication of a Monteggia
fracture-dislocation. If left untreated, the dislocated radial head
later becomes symptomatic. The purposes of this study were firstly,
to evaluate the clinical and radiological results of open reduction
of the radial head and secondly, to identify the factors that may
affect the outcome of this procedure. This retrospective study evaluated 30 children with a chronic
Monteggia lesion. There were 18 boys and 12 girls with a mean age
of 7.4 years (4 to 13) at the time of open reduction. The mean interval
to surgery, after the initial fracture, was 23.4 months (6 to 120).
Clinical grading used a Kim modified elbow score: radiological outcome
was recorded. The effect of the patient’s age, gender, duration
from initial injury, Bado classification, and annular ligament reconstruction
were analyzed. The mean follow-up was 42.2 months (15 to 20).Aims
Materials and Methods
Fixation has been shown to be the primary indicator of an implant's long-term success. Failure to achieve attachment, especially in acetabular and TKR, has been attributed to a lack of initial stability and gaps between the implant and bone. Gaps greater than 150 microns allow fibrous tissue to form. Properly addressing implant design features can help avoid adverse outcomes. ASTM International Standards (F1854-09) do not assess the relationship between porosity of the coating and that of cancellous bone, which can lead to an absence of mechanical interlock. This study developed a virtual program that uses human cancellous bone to predict potential skeletal attachment for implants properly placed for TJR. The goal of the Virtual Paradigm was to assess initial contact surface area at the time of implantation. Seven human femurs and tibias were used. Bones from 11 males and 3 females were used, ages ranging from 40 to 61. Five porous coatings were assessed: Biofoam (Wright Medical), Fiber Mesh, CSTI, Tantalum (Zimmer), and P² (DJO Global).Introduction
Methods
With the arrival of the 21st century, there were clear expectations that cementless fixation in total joint replacements (TJR), and the translational animal protocols for introducing new coatings and surface treatments clinically, had been established. Despite the extensive literature in the 1980s and 1990s demonstrating a translational pathway for predicting skeletal attachment, there remain clinical reports of mechanical implant loosening in both cementless total hip acetabular and total knee components. Before screening a new porous coating or surface treatment, it is important to note that there has been only one experimental translational load-bearing model that has had human (1–3), sheep (4–5), clinical (6–8), and implant retrieval verification confirming skeletal attachment in these types of components, the intracondylar model (1–5,8). What makes the intracondular model predictive of coating or surface treatments for implant attachment is the ability of the model to replicate the healing response of cancellous bone, the main attachment bone tissue to THR acetabular and TKA implants. A lot of the confusion rests with a lack of understanding of the bone response differences between the intracondylar and transcortical animal models. The goal of this study was to test the hypothesis that the intracondylar model can provide positive and negative surface attachment data, whereas, the transcortical model can only provide positive and false positive attachment data. Five skeletally mature sheep will have been implanted with two 13×8 mm plugs (500 mm larger than the 7.5 mm drilled holes) two plugs transcortically and two intracondylarly. One plug will be titanium with CP porous coating. Another plug is made of petrified dinosaur poop with similar dimensions (see Figure 1). Another five sheep will also be implanted transcortically and intracondylarly using plugs with 500 mm inset of the same materials and dimensions. Again, two implants at each site.Introduction:
Methods:
