Introduction

Simultaneous correction of knee varus malalignment with medial open wedge high tibial osteotomy (MOWHTO) combined with anterior cruciate ligament (ACL) surgery aims to address symptomatic unicompartmental osteoarthritis in addition to restore knee stability in order to improve outcomes. The aim of this study is to present at least 5 years results of 32 patients who underwent simultaneous knee realignment osteotomy with ACL surgery.

Background

Return to sports after anterior cruciate ligament reconstruction (ACLR) is multifactorial and rotational stability is one of the main concerns. Anterolateral ligament reconstruction (ALLR) has been recommended to enhance rotational stability.

Background

Medial open wedge high tibial osteotomy (MOWHTO) has been accepted as a highly effective option for the treatment of medial unicompartmental osteoarthritis of the knee. Although pain in the medial joint line is significantly relieved after MOWHTO, some patients complain of pain over pes anserinus after the osteotomy, necessitating implant removal for pain relief.

Purpose: Intraarticular use of anaesthetic agents is common for postoperative pain relief after arthroscopic knee surgery. In this study, we have evaluated and compared the effects of Bupivacaine, Levobupivacaine and Tramadol both invivo and invitro experimental rat models on articular cartilage and chondrocytes.

Materials and Methods: Invivo Experiment: 1. Injections: Thirty mature Sprague-Dawley rats weighing 230 – 300 g were randomized into 3 groups. Bupivacaine (Group 1), Levobupivacaine (Group 2) and Tramadol (Group 3) were injected into the right knee joints and physiological 0.9% saline into the left. 2. Histopathologic Analysis: The specimens were fixed, decalcified and stained with Hematoxylen and Eosin (H& E) and Toluidin Blue. All slides were examined by the same pathologist, who was blinded to the injectate used in each joint. All samples were evaluated histopathologically according to the recommendation of International Cartilage Repair Society’s osteoarthritis and cartilage histopathology grading and staging system. Invitro Experiment: Articular cartilage cells of the rats were cultured and seeded. Cartilage cell seeded samples (104 cells/mL) were incubated in three different anesthetic agents (0,5%); Bupivacaine, Levobupivacaine, and Tramadol respectively. Cell Titer 96TM Nonradioactivity Cell Proliferation (MTS) assay was used to determine the cell density on the samples.

Results:

Invivo: There were pathologic changes like cartilage hypertrophy, active chronic inflammation with abscess formation, cellular proliferation, focal vertical fissures and focal discontunity on cartilage matrix at superficial zone in all three groups on the drug injected sides. Although those histopathologic findings were not found statistically significant when compared the OARSI grade, OA stage and OA score with the control groups (p> 0.05), statistically significant higher OARSI grade, OA stage and OA scores were detected when compared the Levobupivacaine injected group after 10 days with the Levobupivacaine injected group after 48 hours (p< 0.01 [ p=0.008]).

Conclusion: No report has been appointed comparing the effects of the mentioned three drugs both invivo and invitro. Although chondrotoxicity of Bupivacaine was less harmful than Levobupivacaine and Tramadol, these findings suggest that local anesthetics negatively affect articular cartilage and chondrocytes. Given that chondrocyte loss has been implicated in the development of chondrosis and osteoarthritis, orthopaedic surgeons should be careful in their preference for pain control with intraarticular drug injections after arthroscopic procedures.

A conventional implant/bone construct typically involves a plate fixed to a fracture bone via set of screws aligned vertically to the plate/bone interface. In this study new configurations of plate/bone constructs with varied screw angulations were tested. The conventional screw configurations a parallel set of screws aligned vertical to interface were tested against two new configurations, called the divergent configuration and the convergent configuration. A total of four construct systems were prepared for tests. The samples used in the experiments are listed. Sample A, named conventional construct, used a set of parallel screws drilled vertical to the interface plane. Sample B, named convergent construct, used screw holes drilled such that their axes converged. Samples C and D, named divergent construct, used screw holes with diverging axes. The difference between Samples C and D is in the angle of alignment between their screw axes and the normal to the interfacial plane, the former drilled at 150 and the latter at 300. The load displacement curves for the four samples are shown. The failure loads, along with the mode of failure for each sample are read from the load-displacement curves. At a first glance, it is observed that the sample with highest pullout strength in terms of failure load is the conventional construct (A). This is followed by the divergent constructs (C and D), and the sample with the lowest strength is the convergent construct. It takes a more careful investigation, however, to note that similar results will not apply when one takes the average pullout stiffness as a criterion. Here, we define the average pullout stiffness of the structure as It is immediately noticed that samples producing the highest stiffness are those prepared as divergent constructs (C and D), followed by the convergent construct (B), and finally, Sample A produced the lowest stiffness. Also note that the initial portion of the load-displacement curve for Sample D (300 screws) is highly nonlinear, although the curve then assumes a linear shape. The stiffness obtained in the linear region of Sample D, and that of Sample C are quite close in comparison.

This initial deviation in the curve of 300 divergent screws may be explained by a self-aligning motion of the screws as the load is applied, during which the angle of alignment tends to decrease towards a smaller angle. As the angle gets closer to that of Sample C and the curve becomes linear, the stiffness produced by Sample D, approaches to that of Sample C.

As a result, we have found the divergent constructs to be a promising alternative to the conventional set of screws, used in treating fracture involving bones with osteoporosis. Moreover, research needs to be focused on determination of an optimal angle of alignment, the number of screws to be used and the optimal distance between each screw for the divergent construct.