This article shows there is no trade-off between quality and costs: Lean Six Sigma improves quality and, at the same time, reduces costs.

The DMAIC approach has proven to be a helpful strategy ensuring a significant decreasing of the LOS. Furthermore, through its implementation, a significant reduction of the average costs of hospital stay can be achieved. Such a versatile approach could be applied to improve a wide range of health care processes.

In total knee arthroplasty (TKA) and total hip replacement (THR) the restoration of the normal joint function represents a fundamental feature. A prosthetic joint must be able to provide motions and to transmit functional loads.As reported in the literature, the stress distribution may be altered in bones after the implantation of a total joint prosthesis. Some scientific works have also correlated uncemented TKA to a progressive decrease of bone density below the tibial component. Antibiotic-loaded bone cements are commonly employed in conjunction with systemic antibiotics to treat infections. Furthermore, nanoparticles with antimicrobial activity have been widely analysed. Accordingly, the current research was focused on a preliminary analysis of the mechanical and antibacterial activity of a PMMA-based bone cement loaded with gold nanoparticles. The obtained results demonstrated that nanocomposite cements with a specific concentration of gold nanoparticles improved the punching performance and antibacterial activity. However, critical aspects were found in the optimization of the nanocomposite bone cement.

BackgroundCulturing of the sonication fluid of removed implants has proven to be more sensitive than conventional periprosthetic tissue culture for the microbiological diagnosis of prosthetic joint infection. Since bacteria surviving on antibiotic-loaded cement spacers used in a two-stage exchange protocol for infected arthroplasties may cause the persistence of infection, in this study we asked whether the sonication also could be used to identify bacteria on antibiotic-loaded cement spacers removed at the second surgical stage during a two-stage exchange procedure to confirm whether or not the prosthetic joint infection had been eradicated.MethodsWe cultured the sonication fluid of cement spacers that had been originally implanted in a two-stage exchange protocol in 21 patients (mean age, 66 years) affected by prosthetic joint infection (16 total knee prostheses and 5 hip prostheses). The cement spacers were vortexed for 30 seconds and then subjected to sonication (frequency 35–40 KHz). The resulting sonicate fluid was cultured for aerobic and anaerobic bacteria.ResultsThe sonication fluid culture of the removed spacer was positive in six patients (29%), with isolation of methicillin-sensible Staphylococcus Aureus (MSSA) in three cases, methicillin-resistant Staphylococcus Aureus (MRSA) in one case and Pseudomonas Aeruginosa in two cases. In three of these positive cases, the traditional culture of periprosthetic tissue was negative. Two patients with positive sonication culture of the spacer were successfully treated by early debridement of the revision prosthesis and systemic antibiotic therapy. In three patients a knee arthrodesis was planned and performed as the second surgical stage. In two of them the infection was caused by highly resistant Pseudomonas Aeruginosa. The other patient with a MSSA infection had been poorly compliant with the systemic antibiotic therapy due to her mental impairment. The patient originally affected by MRSA infection of his primary hip arthroplasty developed recurrent infection of his revision prosthesis and eventually underwent Girdlestone arthroplasty.ConclusionsThe sonication culture can be used to discover any bacteria on the antibiotic-loaded cement spacer during a two-stage exchange protocol, thus permitting the adoption of timely treatment options, such as the early prosthetic debridment.

Primary total knee arthroplasty (TKA) is a reliable procedure with reproducible long-term results. Nevertheless, there are conditions related to the type of patient or local conditions of the knee that can make it a difficult procedure. The most common scenarios that make it difficult are discussed in this review. These include patients with many previous operations and incisions, and those with severe coronal deformities, genu recurvatum, a stiff knee, extra-articular deformities and those who have previously undergone osteotomy around the knee and those with chronic dislocation of the patella. Each condition is analysed according to the characteristics of the patient, the pre-operative planning and the reported outcomes. When approaching the difficult primary TKA surgeons should use a systematic approach, which begins with the review of the existing literature for each specific clinical situation.