Total hip replacement is showing, during the last decades, a progressive evolution toward principles of reduced bone and soft tissue aggression. These principles have become the basis of a new philosophy, tissue sparing surgery. Regarding hip implants, new conservative components have been proposed and developed as an alternative to conventional stems. Technical and biomechanical characteristics of metaphyseal bone-stock-preserving stems are analyzed on the basis of the available literature and our personal experience. Mayo, Nanos and Metha stems represent, under certain aspects, a design evolution starting from shared concepts: reduced femoral violation, non-anatomic geometry, proximal calcar loading and lateral alignment. However, consistent differences are level of neck preservation, cross-sectional geometry and surface finishing. The Mayo component is the most time-tested component and, in our hands, it showed an excellent survivorship at the mid-term follow-up, with an extremely reduced incidence of aseptic loosening (partially reduced by the association with last generation acetabular couplings). For 160 implants followed for a mean of 4.7 years, survivorship was 97.5% with 4 failed implants: one fracture with unstable stem, 1 septic loosening and 2 aseptic mobilizations. DEXA analysis, performed on 15 cases, showed a good calcar loading and stimulation, but there was significant lateral load transfer to R3–R4 zones, giving to the distal part of the stem a function not simply limited to alignment. Metaphyseal conservative stems demonstrated a wide applicability with an essential surgical technique. Moreover, they offer the options of a “conservative revision” with a conventional primary component in case of failure and a “conservative revision” for failed resurfacing implants.

The choice between different surgical options depends on bone defect dimension and characteristics but are also patient-related. Reestablishment of well-aligned and stable implants is necessary for successful reconstruction, but this can't be accomplished without a sufficient restoration of an eventual bone loss.

Hip dislocation is a major and common complication of total hip arthroplasty (THA), which appears with an incidence between 0.3% and 10% in primary total hip arthroplasties and up to 28% in revision THA. The hip dislocations can be classified into three groups: early, intermediate and late. Approximately two-thirds of cases can be treated successfully with a non-operative approach. The rest require further surgical intervention. The prerequisite to developing an appropriate treatment strategy is a thorough evaluation to identify the causes of the dislocation. In addition, many factors that contribute to THA dislocation are related to the surgical technique, mainly including component orientation, femoral head diameter, restoration of femoral offset and leg length, cam impingement and condition of the soft tissues. The diagnosis of a dislocated hip is relatively easy because the clinical situation is very typical. Having identified a dislocated hip, the first step is to perform a closed reduction of the implant. After reduction you must perform a computed tomography scan to evaluate the surgical options for treatment of recurrent dislocation that include: revision arthroplasty, modular components exchange, dual-mobility cups, large femoral heads, constrained cups, elimination of impingement and soft tissue procedures. The objective is to avoid further dislocation, a devastating event which is increasing the number of operations on the hip. To obtain this goal is useful to follow an algorithm of treatment, but the best treatment remains prevention.

PurposeSeveral studies have investigated effectiveness of fibrin spray or bipolar sealer to control peri-operative bleeding and reduce the need for blood transfusion, but a direct comparison between the two methods has not been previously performed. We conducted a prospective randomised trial, with standard electrocautery as a control group.MethodsIn our investigation, 95 patients were randomised to one of three parallel groups receiving (1) 10 mL of topical fibrin spray before closure, (2) haemostasis with radiofrequency energy using a bipolar sealer, and (3) standard electrocautery. All patients and staff apart from the surgeons were blinded until data analysis was complete. Peri-operative blood loss has been calculated using a formula described by Ward and Gross (considering estimated patient blood volume, pre- and post-operative haemoglobin and haematocrit levels), with mention of eventual blood re-infusion or transfusion, at given intervals from surgery (6, 24, 48, 72 hours).ResultsMean blood loss was lower for both methods investigated, compared to the control group at every time interval considered, although differences were stronger for fibrin spray [Quixil]. Mean blood saving at the given intervals from surgery (6–24–48–72 hours) was respectively 96 ml, 129 ml, 296 ml, and 121 ml for bipolar sealer [Aquamantys] and 235 ml, 368 ml, 642 ml, and 490 ml for fibrin spray. These results are statistically significant (p = 0.05) for fibrin spray at every interval compared to control values, while a significance is detectable for bipolar sealer only at 48 hours after surgery.ConclusionsThe fibrin spray group had the best performance in terms of blood loss, significantly reduced in comparison with the control group and bipolar sealer group. Blood loss reduction for the bipolar sealer was remarkable only at 48 hours, compared with the control group. Blood loss reduction for fibrin spray was significant at every time interval considered. Differences between the two treatments investigated and the control group narrowed slightly at 72 hours, as an expression of spontaneous homeostasis. Notable is the fact that blood volume saved with fibrin spray at 24 and 48 hours is comparable to the volume of at least one blood unit. A cost-effectiveness analysis should be considered in term of expense, biological risks (related to blood transfusion or human-derived products use) and bleeding-related complications.

The MIPO technique for proximal humeral fractures was safe and reproducible for most common patterns of fracture. Major complication rate was apparently low due to a soft tissue sparing, deltoid muscle and circumflex vessels, with easy access of the bar area to correct positioning of the plate.

We used scanning electron microscopy to perform an ultrastructural analysis and two optical interferometric profilers to measure roughness on 40 prosthetic femoral heads. We expressed roughness as Ra (roughness average) value and Rsk (roughness skewness) value. Our results show that in order to obtain an ideal surface finish a low or not very high Ra value and a negative Rsk value are needed. The presence of depressions or holes (rather than scratches) with smooth (rather than sharp) edges seems to improve the lubrication and wettability properties.Résumé Nous avons utilisé la microscopie électronique à balayage pour une étude ultrastructurale et mesuré par interféromètres à lecture optique la rugosité sur 40 têtes fémorales prothétiques. Nous avons exprimé la rugosité comme Ra (la moyenne de la rugosité) et Rsk qui est une valeur des asymétries du profil par rapport à la ligne moyenne. Nos résultats démontrent que pour obtenir une surface idéale, un bas ou pas très haute valeur de Ra et une valeur négative de Rsk sont nécessaires. La présence de dépressions ou vallées (au lieu de griffes) avec un bord lisse (au lieu de tranchant) paraît améliorer la lubrification et les propriétés de mouillabilité.

Resurfacing replacement represents the most conservative solution available for total arthroplasty of the hip. However, despite the excellent results reported by highly experienced surgeons, a small but not insignificant body of literature has been published on the more controversial aspects of this approach, mainly those related to the biological and mechanical vulnerability of the retained epiphysis. We report here our evaluation of most of the variables inherent to this procedure (surgical exposure, implant design, technical steps). Based on our results, we conclude that the short-term outcome is strongly related to the surgical approach and the relationship between implant design and cementing technique. Even if posterior approaches are currently widely accepted for resurfacing replacement, the ability to preserve the medial circumflex artery has been questioned, and an alternative exposure has been proposed with good results (antero-lateral, lateral and digastric trochanteric osteotomy). Moreover, a minimally invasive posterior approach could increase the risks of vascular damage. Alternatively, inner implant geometry could affect the distribution of cement over the epiphysis when other variables (direct or indirect cementing technique, viscosity) are not properly selected.

Background The renewed popularity of resurfacing hip arthroplasty in the last 10 years has generated a remarkable quantity of scientific contributions based on mid-and shortterm follow-up. More than one paper has reported a consistent early revision rate as a consequence of biological or biomechanical failure. Two major complications are commonly described with resurfacing implants: avascular necrosis and femoral-neck fracture. A close relationship between these two events has been suggested, but not firmly demonstrated, whereas cementing technique seems to be better understood as potential cause of failure. Methods We performed an in vitro study in which four different resurfacing implants were evaluated with a simulated femoral head, two types of cement, (low and high viscosity) and two cementing techniques: direct (cement apposition directly on the femoral head) and indirect (cement poured into the femoral component). Results High-viscosity cement showed homogeneous distribution over the entire femoral head. Low-viscosity cement showed a massive polar concentration with insufficient, if not absent, distribution in the equatorial zone. Conclusion Polar cement concentration could be a risk factor for early implant failure due to two effects on the femoral head: biological (excessive local exothermic reaction could cause osteocyte necrosis) and biomechanical (which could lead to uneven load distribution on the femoral head).