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Periprosthetic joint infections (PJIs) after total joint replacement are dramatic complications. While more commonly observed in the postoperative period, PJIs may occur throughout life with negative physical and psychological repercussions on the patient, leading to potentially fatal consequences in the absence of treatments. Male gender, advanced age, high body mass index, comorbidities, immunosuppression, prolonged operative time (>90′) and tourniquet time (>60′) have been identified as significant contributors to the development of PJI following total joint arthroplasty. PJI has been identified as the leading cause for failure of total knee arthroplasty (TKA). The frequency of joint replacement is estimated to grow in all countries, implying an increased risk of PJIs. The same future forecasts suggest an increase in PJIs-related health care costs after the failure of primary knee replacement, especially for PJIs caused by methicillin-resistant Staphylococcus Aureus. The need to find preventive strategies for PJIs can no longer be postponed since the socioeconomic implications of the PJI after TKA remain overwhelming.

The objective of this study is to experimentally examine the effect of applied load and surface texture on friction of UHMWPE in total joint replacement by measuring the coefficient of friction (COF) between CoCrMo pin and UHMWPE discs. A CoCrMo pin with the dimensions of 11 mm in diameter and 18 mm in length was machined to obtain the surface roughness of 0.25 µm. For preparing different surface texture, ten UHMWPE discs with the dimensions of 88 mm in diameter and 5 mm in thickness were machined by two different machining processes of milling and turning to obtain two roughness values of 2.5 and 0.25 µm. 25 mg/ml BSA was made by mixing BSA powder in 10% PBS. A frictional testing apparatus was developed and carried out for the calculation of COF. Results show that the COF increases with the increase of the applied load in both cases of the UHMWPE roughness of 0.25 and 2.5 µm. With the UHMWPE roughness of 0.25 µm, the COF decreases when the surface texture machined by milling compared to that by turning in both cases of the applied loads of 4 and 16 N; however, with the UHMWPE roughness of 2.5 µm, the COF increases when the surface textures machined by milling compared to that by turning. These results suggest that both the applied loads and the surface textures have important effects on the friction of UHMWPE.

The temporomandibular joint is a complex anatomical structure, which has manifold disease processes that can be quite debilitating in nature. The chapter begins with a brief anatomy review, as grasping an understanding of the anatomy and the dynamics of the joint is the basis on which further comprehension of the pathological entities lies. From there, we discuss the salient disease processes and treatments (both conservative and surgical) that candidates may be tested on during the oral examination. We also provide guidance points along the way that the candidate may find useful.

Patients undergoing orthopedic surgery are subject to many perioperative insults. Unique to this patient population however is the intravasation of bone, cement, and marrow during the surgical instrumentation process that occurs frequently and may contribute to the pathophysiology of complications seen in the perioperative period. The risk of perioperative complications may be dependent on the level of the operative insult on one hand and end-organ reserve on the other. Identifying interventions that can reduce perioperative insults and instituting programs to identify patients at risk may result in a decrease in the odds for perioperative complications. This chapter explores possible sources of injury and related processes and attempts to relate them to complications frequently seen in orthopedic patients.

Wear and/or failure of ultra-high molecular weight polyethylene (UHMWPE) component after total joint replacement are major factors restricting the clinical longevity of artificial joints. In order to minimize the wear and failure of the UHMWPE and to improve the clinical longevity of artificial joints, it is necessary to clarify the factors influencing the wear and failure mechanism of the UHMWPE. The generations of catastrophic wear and/or failure of the UHMWPE acetabular cup liner are frequently observed in retrieved hip prostheses. The primary purpose of this study was to investigate the cause of catastrophic wear and/or failure of the UHMWPE liner in hip prosthesis. The authors focused on change in mechanical state of the UHMWPE liner due to contact with metallic component as a factor influencing the wear and failure mechanism of the UHMWPE liner. Contact analyses between the metallic components and the UHMWPE liner by using the finite element method (FEM) were performed to investigate the mechanical state of the UHMWPE liner. It was found that high contact stresses, which exceed the yield stress of UHMWPE, and considerable plastic deformations occurred in the rim of the UHMWPE liner. It was also found that high stress concentrations occurred near screw holes in the acetabular cup and notches in the UHMWPE liner. This study confirmed that change in mechanical state due to contact with metallic component is the cause of catastrophic wear and/or failure of the UHMWPE liner.

Outpatient total joint replacement is safe and economical when done in the setting of a comprehensive program. A successful outpatient episode of care demands a consistent and measurable sequence of events that integrates all preoperative, operative, and postoperative elements and requires a program that prioritizes an efficient and streamlined approach focusing on standardization, communication, staff training, and infrastructure. Such a program must begin with measurable patient engagement, which will need to be operationalized across the entire episode of care.

Gout, the most common inflammatory arthritis, has a predilection for acute flares in the postoperative setting. In the context of orthopedic surgery, patients may be at additional risk since comorbidities prevalent among those who undergo total joint replacement, for instance obesity, are also risk factors for gout. Despite this association, there is a lack of controlled studies to guide the perioperative management of this common rheumatologic condition. This chapter will summarize general principles of gout management, including the management of acute flares as well as urate-lowering therapy. We will review the application of these principles to the preoperative, immediate postoperative and finally discharge planning phases of care for an orthopedic patient.

Musculoskeletal disorders, particularly those of the spine and joints, are a leading cause of pain and disability throughout the world. Traditional methods of treatment have demonstrated limited effectiveness for repairing injured or degenerated musculoskeletal tissues, requiring patients to undergo major surgeries including total joint replacement or spinal fusion, which carry significant risk and may not completely relieve their symptoms. Regenerative medicine has the potential to revolutionize treatment of musculoskeletal disorders, restoring healthy tissue structure and function through the use of cells, bioactive materials, and biological factors. Developing effective regenerative medicine strategies requires knowledge of the underlying biological processes that drive tissue formation, degeneration, and repair. In this chapter, we provide a brief overview of the basic science concepts relevant to regenerative medicine strategies for the spine and joints.

Both obesity and joint disease are increasing at a rapid pace. Accompanying this growth in these disease states are interventions for them such as bariatric and orthopedic surgery. Obesity is a clear risk for the development and progress of joint disease. In addition, obesity can affect the outcomes of total joint replacement. Bariatric surgery provides relief from the burden of obesity and may affect the progression of joint disease and outcomes for total joint replacement. This chapter reviews the risks of obesity and joint disease and its treatment along with the benefit of bariatric surgery for the patient with both obesity and joint disease.

This chapter presents the diagnostic criteria, treatment planning, and surgical protocols for the application of computer-assisted surgical simulation (CASS) for patients requiring TMJ total joint replacement and orthognathic surgery (C-TJR-OS). The CASS protocol decreases the preoperative workup time and increases the accuracy of model preparation and subsequent surgery.

One of the most challenging reconstructions in maxillofacial surgery is that involving the condyle and ramus. Common reconstructive techniques involve either autogenous bone grafting such as costochondral rib grafting, a sliding posterior ramus border osteotomy, microvascular free fibula graft, or alloplastic reconstruction involving either stock or custom total joint replacement. None of these techniques specifically address the articular disc and some address only bone and not soft tissue. Bioengineering, which uses cells, molecules, chemistry, and scaffolds with engineering principles, is now providing novel solutions to complex biological problems.

This chapter focuses on diagnosis and treatment of temporomandibular joint disorders (TMD) including myofascial pain disorder (MPD) and disorders of the joint itself. Noninvasive treatments include physical therapy, pharmacotherapy, massage, thermotherapy, and occlusal appliance therapy. Lastly minimally invasive procedures such as arthrocentesis and arthroscopy as well as surgical procedures such as arthroplasty and total joint replacement will be discussed.

Total joint arthroplasties have increased significantly in number over the past several decades and appear to continue to increase exponentially in correlation with the demands of an aging population. The multifaceted approach to providing patients with a lasting implant is divided among the patient characteristics, surgical skills, and the biomaterials of the implant. The following chapter reviews the most commonly used biomaterials for total joint arthroplasty, their properties, their interaction with other implants, and the current progress in improving each material for greater stability, sterility, and survivability. This chapter also highlights the clinical relevance of these materials by presenting several case reports of failures of varying materials.

Severe painful arthrosis in adolescent patients is a difficult dilemma. The surgical treatment options include total joint replacement or hip arthrodesis. As the longevity of hip replacements continues to improve, the option of hip replacement looks enticing. However, the long-term outcomes of joint replacements in adolescent patients still remain concerning. As such an argument can be made that in adolescent patients with severe painful degenerative joint disease of the hip, arthrodesis remains the preferred treatment option. Short-term problems with hip arthrodesis include nonunion, malalignment, and limb length discrepancy. Long-term problems include degenerative low back pain and ipsilateral knee pain as well as a difficult conversion to total hip arthroplasty. While the short-term problems can be minimized using the approach described in this chapter, the long-term problems of adjacent segment degenerative joint disease cannot and may in fact necessitate future conversion to total hip arthroplasty. Avoiding the use of complex plating techniques and minimizing trauma to the abductor musculature during the hip arthrodesis are important factors to consider for future total hip arthroplasty.

Temporomandibular joint dislocation can be acute, chronic, or recurrent. Chronic or long-standing dislocation is rarely encountered and can require difficult and invasive surgical intervention to manage successfully. Management of chronic dislocation can include closed reduction, arthrotomy with open reduction, eminectomy, coronoidectomy, or condylectomy. Alloplastic reconstruction of the temporomandibular joint may allow for more predicable outcomes in the management of irreducible chronic dislocation. A managed case of chronic temporomandibular joint dislocation is presented in this chapter, and the literature is reviewed. The case described illustrates the importance of early recognition and treatment of temporomandibular joint dislocation. Relevant clinical and radiographic findings are discussed. It is important to remember that failure to promptly identify and treat a dislocation can lead to significant patient morbidity, increased difficulty in management, and long-term temporomandibular joint dysfunction.

Ever since orthopedic total joint replacement (TJR) was introduced by Sir John Charnley [1], orthopedic joint replacement has gained popularity given the considerable improvement in biocompatibility, functionality, and durability of these devices [2, 3]. Many of these alloplastic joints can function properly for decades [4–6]. However, one of the potential drawbacks to this technological and clinical advancement in the management of end-stage joint disease is the susceptibility of these devices to infection. Management of these infections involves elimination of the infection and returning the joint to function. In order to achieve these goals, early diagnosis and a rational management plan that includes surgical intervention, combined with appropriate antibiotic therapy, are essential [7, 8].

The most important consideration in the treatment of the temporomandibular joint dysfunction (TMD) patient is making a proper diagnosis and selecting an appropriate treatment using evidence-based guidelines and algorithms. The approach to treatment should include strategies to educate the patient about their disease process, the current stage of that disease, how to manage it, and preventative approaches to reduce the likelihood of disease progression. Diet and lifestyle changes play an important role in the management of TMD just as they do in many other systemic diseases. When combined with appropriate surgical intervention in the properly selected patient, outcomes can be better predicted with the potential to slow or prevent the development of internal derangement.

All engineering constructs require appropriate materials to meet safety and effectiveness standards. It is an unfortunate observation that in the decades of the 1970s and 1980s, synthetic materials were utilized in the management of temporomandibular joint (TMJ) pathology that proved to be inappropriate and—sometimes—even dangerous. This was a failure that remains an embarrassment to the biomaterials community and to the bioengineering designers who selected those materials and are now redoubling their current efforts to do better.

Medical application is one of the most exciting and rewarding research areas of the materials science. Examples from our daily life are sutures, catheters, heart valves, pacemakers, breast implants, fracture fixation plates, nails and screws in orthopedics, dental filling materials, orthodontic wires, as well as total joint replacement prostheses. During the past decades, both an ageing population and a democratization of high-risk sports have led to a surge of bone-related diseases and bone fractures, which must be treated through implants. In order to be accepted by the living body, all implantable items must be prepared from a special class of materials, called biomedical materials or biomaterials in short.