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Engineering materials, in many forms have been implanted into the human body since the end of the eighteenth century. Implant surgery has developed to the extent that implants are now used in most branches of surgery and are becoming increasingly more sophisticated. Orthopaedic surgery uses more implants than any other branch of medicine. In the last decade, various joint replacements have been developed. However, many implants have failed in the past and even now there are occasional failures. Many of the failures are attributed to poorly chosen or badly used materials, high stress concentration leading to crack initiation and growth, loosening of the implant due to a poor fixation and/or a non-adequate adhesion between the implant/cement/bone interfaces. The present paper reviews the development in artificial implants during the last decade considering materials, analysis and manufacture processes.

Three case studies are presented in which untempered martensite produced during forming or use caused premature failure or failures in unexpected regions. The sources of formation of untempered martensite observed were: laser cutting of circular saws, friction originated from poor fixation of blades, and uncontrolled thermal cycling in the vicinity of a weld. Due to its very high hardness, untempered martensite favors the appearance of microcracks that develop into premature catastrophic failures.

The aim of the study was to determine whether the order of cell collection (ie, obtaining either endocervical first or ectocervical cells first) has an effect on the quality of the Papanicolaou smear. 1129 smears were obtained using an Ayre spatula and an endocervical brush. In 564 cases, the endocervical brush was used first, and in 565 cases, the spatula was used first. The number of smears obscured by blood, the smears without endocervical component, and the smears with poor fixation were compared between the two groups. More smears were partially obscured by blood when brush was used first (78, 13.8% compared with 48, 8.5%, P = 0.004). No endocervical component was found in seven (1.2%) smears from the brush-first group compared with five (0.9%) of the spatula-first group, which is an insignificant difference. There were no significant differences in the number of poor-fixated smears, too-thick smears, and satisfactory smears but limited by inflammation between the two methods. The quality of the Papanicolaou smear can be improved by using the Ayre spatula first followed by the endocervical brush. Fewer smears will be contaminated by blood which may result in more squamous intraepithelial lesions being detected.

Cobalt alloys have been used successfully as bearings since the earliest days of arthroplasty, now seeing use in the overwhelming majority of knees and hips. Although reports of fracture, corrosion, and other unexpected events leading to revision are sporadically found throughout the literature over the last 3 decades, failure reports involving cobalt components have historically been dwarfed by failure reports of polyethylene oxidation, osteolysis, and poor fixation, among others. The current issue is a reminder that the human body and its permanently implanted devices constitute a fragile system, and even small perturbations of this system from cobalt alloys can result in untoward events with devastating outcomes. Through a thematic selection of case reports, the importance of good science and learning from the patient is underscored. Over the last decade, we have seen an uptick in metal-related failure reports secondary to wear of metal-on-metal (MoM) articulations. Much of the science aimed at understanding the root problem has been outstanding and exceptionally informative for future implementation of any bearing couple, not just MoM. The in vitro focus has necessarily been on discrete contributors to the problem such as inclination angle, cup opening, materials, head size, patient selection, and so forth. Due in large part to these studies and registry-related reports of patient outcomes,MoMusage is now

The use of suture anchors and tacks around the shoulder requires a thorough knowledge of the proper use of the devices and how to insert them. Although typically not technically demanding, suture anchors and tacks can present unique and frustrating challenges to the patient and the surgeon. These challenges can occur whether the procedure is performed via an open or arthroscopic approach, but knowledge of the potential challenges may optimize the surgical result and prevent complications. Complications can be categorized as technique-related or device-related issues (mechanical or biologic failure). Techniquerelated complications include problems with the delivery systems, anchor malpositioning, and suture management issues, such as knots not sliding. Device-related complications include implant fracture, migration secondary to poor fixation, synovitis from implant degradation, and osteolysis. This review describes the prevention of these and other complications, addresses the indications or need for intervention, and suggests potential solutions when intervention is indicated.

We have evaluated 30 Mittelmeier hips on an average 3.3 years after the operation. Seven hips had been revised because of severe pain and mechanical loosening and one because of fracture of the threaded ceramic cup. Only five of the remaining 22 hips were asymptomatic. There was radiographic migration of the acetabular and femoral components in more than one third of the hips and increased scintimetric values around the femoral component in all but two hips. Unfavorable design of the Mittelmeier prosthesis may be an important etiologic factor contributing to poor component fixation and inferior clinical results.