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Introduction: Although Total Knee Arthroplasty (TKA) is a successful procedure, a significant number of patients are still unsatisfied, reporting instability at the mid-flexion range (Mid-Flexion Instability-MFI). To avoid this complication, many innovations, including load sensors (LS), have been introduced. The intraoperative use of LS may facilitate the balance of the knee during the entire range of motion to avoid MFI postoperatively. The objective of this study was to perform a Gait Analysis (GA) evaluation of a series of patients who underwent primary TKA using a single LS technology. Methods: The authors matched and compared two groups of patients treated with the same posterior stabilized TKA design. In Group A, 10 knees were intraoperatively balanced with LS technology, while 10 knees (Group B) underwent standard TKA. The correct TKA alignment was preoperatively determined aiming for a mechanical alignment. Clinical evaluation was performed according to the WOMAC, Knee Society Score (KSS) and Forgotten Joint Score, while functional evaluation was performed using a state-of-the-art GA platform. Results: We reported excellent clinical results in both groups without any statistical difference in patient reported outcome measurements (PROMs); from a functional standpoint, several GA space–time parameters were closer to normal in the sensor group when compared to the standard group, but a statistically significant difference was not reached. Conclusions: Gait Analysis represents a valid method to evaluate TKA kinematics. This study, with its limitations, showed that pressure sensitive technology represents a valid aid for surgeons aiming to improve the postoperative stability of TKA; however, other factors (i.e., level of intra-articular constraint and alignment) may play a major role in reproducing the normal knee biomechanics. [ABSTRACT FROM AUTHOR]

Purpose: During the last decade, total hip arthroplasty has become a common procedure performed in young patients, as well as elderly ones. This has led to an increase in total hip arthroplasty revisions. Loosening of primary components with associated bone loss represents the major cause of total hip arthroplasty revision. This study evaluates the safety and performance of an enzyme-deantigenic equine-derived bone graft material in acetabular defect reconstruction. Methods: Records of 55 patients who were treated for Paprosky type II or III acetabular bone defects with arthroplasty revisions using equine-derived bone and followed for an average of 34 months (range from 24 to 48 months) were analyzed. Results: Of the 55 revisions, 49 (89%) were regarded as successful, showing good osteointegration without signs of mobilization. Failures included six cases (11%) of mobilization: five cases of aseptic mobilization (9.1% of revisions, 83% of failures) and one case of septic mobilization (1.9% of revisions, 17% of failures). These results are consistent with those of studies having a similar follow-up period for allografts used in combination with trabecular metal components. Conclusions: Results of the present study suggest that enzyme-treated equine-derived bone grafts may be a valid alternative to autogenous and homologous bone grafts in total hip arthroplasty revision. [ABSTRACT FROM AUTHOR]

Orthopaedic simulators are popular in innovative surgical training programs, where trainees gain procedural experience in a safe and controlled environment. Recent studies suggest that an ideal simulator should combine haptic, visual, and audio technology to create an immersive training environment. This article explores the potentialities of mixed-reality using the HoloLens to develop a hybrid training system for orthopaedic open surgery. Hip arthroplasty, one of the most common orthopaedic procedures, was chosen as a benchmark to evaluate the proposed system. Patient-specific anatomical 3D models were extracted from a patient computed tomography to implement the virtual content and to fabricate the physical components of the simulator. Rapid prototyping was used to create synthetic bones. The Vuforia SDK was utilized to register virtual and physical contents. The Unity3D game engine was employed to develop the software allowing interactions with the virtual content using head movements, gestures, and voice commands. Quantitative tests were performed to estimate the accuracy of the system by evaluating the perceived position of augmented reality targets. Mean and maximum errors matched the requirements of the target application. Qualitative tests were carried out to evaluate workload and usability of the HoloLens for our orthopaedic simulator, considering visual and audio perception and interaction and ergonomics issues. The perceived overall workload was low, and the self-assessed performance was considered satisfactory. Visual and audio perception and gesture and voice interactions obtained a positive feedback. Postural discomfort and visual fatigue obtained a nonnegative evaluation for a simulation session of 40 minutes. These results encourage using mixed-reality to implement a hybrid simulator for orthopaedic open surgery. An optimal design of the simulation tasks and equipment setup is required to minimize the user discomfort. Future works will include Face Validity, Content Validity, and Construct Validity to complete the assessment of the hip arthroplasty simulator. [ABSTRACT FROM AUTHOR]

Purpose: The use of tranexamic acid (TXA) in total hip arthroplasty (THA) can significantly reduce blood losses with many clinical and economical advantages. However, no consensus has been reached regarding the optimal regimen for TXA administration. The aim of this study is to analyse and compare the haemostatic effect of two different intravenous (IV) regimens of TXA. Materials and methods: We planned a single-centre, prospective, randomized study including 80 patients who underwent primary unilateral minimally invasive THA because of a hip osteoarthritic degeneration. We divided patients into two groups: the G10 group received two IV doses of 10 mg/kg of TXA, and the G20 group received two doses of 20 mg/kg. Results: No significant differences in mean minimum levels of Hb and HcT stratified by days after surgery were uncovered between the two groups despite the use of two different dosages of TXA. Also the mean blood volume loss was statistically similar between two groups. No differences were also observed regarding the occurrence of adverse effects. Conclusions: In two IV bolus regimens of TXA administration, the use of a dose of 10 or 20 mg/kg provides statistically similar results in blood loss sparing. Therefore, the use of two 10 mg/kg doses could be considered more advisable in order to reduce the potential thromboembolic risks related to this drug. [ABSTRACT FROM AUTHOR]

Tendon injuries are commonly met in the emergency department. Unfortunately, tendon tissue has limited regeneration potential and usually the consequent formation of scar tissue causes inferior mechanical properties. Nanoparticles could be used in different way to improve tendon healing and regeneration, ranging from scaffolds manufacturing (increasing the strength and endurance or anti-adhesions, anti-microbial, and anti-inflammatory properties) to gene therapy. This paper aims to summarize the most relevant studies showing the potential application of nanoparticles for tendon tissue regeneration. [ABSTRACT FROM AUTHOR]

We report our initial experience of total knee arthroplasty (TKA) using customized cutting block technology in 30 TKAs from December 2010 to September 2012. Customized blocks were generated for each of the knees using preoperative magnetic resonance imaging of knee and long-leg weight-bearing radiographs. At 30 days, long-leg radiographs were obtained to evaluate the coronal alignment. Twenty-six of the 30 knees had a mechanical axis restored to within 3° of neutral. We conclude that this technology can be safely used in most of the cases of osteoarthritis. [ABSTRACT FROM AUTHOR]

Acromio-clavicular joint (ACJ) injuries represent nearly half of all athletic shoulder injuries. Stability of this joint depends on the integrity of the acromio-clavicular and coracoclavicular ligaments. Although the traumatic acromioclavicular joint separation is a well-known topic, there are different classifications, diagnostic procedures, concepts of intervention, and a great variety of implants. In this paper, we present an overview of the recent literature about this issue and the results of a retrospective non-randomized study with 2 different techniques. At the first Orthopedic Department of University of Pisa, a retrospective study was performed starting from January 2007 to February 2011 in our electronic database. We selected patient treated with two different techniques (tight-rope system and hook plate) by the same senior surgeon with experience in shoulder surgery. The mean Costant score was 90 for the tight-rope system group and 75 for the hook plate group. At the final follow-up, most of the patients had returned to their preinjury level of activity. Two patients had a breakage of the fixating system. The above-mentioned techniques provided satisfactory results with no loss of reduction except in two cases. The use of the hook plate is useful in fracture-dislocation of ACJ, but this requires another surgery to remove it. On the contrary, the use of the tight-rope system does not require a new surgery or use of expensive synthetic graft or a graft harvested from a distant donor site. [ABSTRACT FROM AUTHOR]

A number of interspinous devices (ISD) have been introduced in the lumbar spine implant market. Unfortunately, the use of these devices often is not associated with real comprehension of their biomechanical role. The aim of this paper is to review the biomechanical studies about interspinous devices available in the literature to allow the reader a better comprehension of the effects of these devices on the treated segment and on the adjacent segments of the spine. For this reason, our analysis will be limited to the interspinous devices that have biomechanical studies published in the literature. [ABSTRACT FROM AUTHOR]

Background: Acetabular cup loosening is the primary reason of revision in total hip arthroplasty; this usually occurs as a result of implant fixation failure. There are a variety of surgical hardware and strategies available to address this problem that is one of the most challenging circumstances in hip surgery. The purpose of this prospective nonrandomized study is to present our preliminary results in the Ist Orthopaedic and Traumatology Unit of Pisa University with Regenerex™ revision shell. Methods: Regenerex™ revision shell is a porous titanium construct optimized for vascularized osteogenesis and designed to accept a cemented all-poly cup. If the bone defects were less than GIR IV or Paprosky type III, the Regenerex™ revision shell was consecutively used, and at the end of December 2011, this shell was placed in 33 patients. In this study, we identified 28 cases with a minimum follow-up of 12 months; the mean interval from surgery to evaluation was 25 months; we performed clinical, functional, and radiologic evaluations. Results: The mean Harris hip score was >83 while the mean Western Ontario and McMaster Universities Osteoarthritis Index score was >75. In five cases, postoperative radiolucent lines were present. No signs of osteolysis were noted around the screws, and none of the 28 cups was thought to be loose. Conclusions: This preliminary report is to our knowledge the first one to be published about clinical and radiological results on Regenerex™ revision shell. Our results are promising, but we need further investigations in order to obtain more data about this material in revision surgery. [ABSTRACT FROM AUTHOR]

Background: Although cementless implants are increasing in popularity, the use of cementless femoral stems for total hip arthroplasty (THA) and hip hemiarthroplasty (HH) in elderly patients remains controversial. The aim of this study was to report the outcomes of a cementless stem used in a large multicentric cohort of elderly patients receiving elective THA and HH for displaced femoral neck fracture. Methods: A total of 293 patients (301 hips) aged 70 years or older (mean age, 78 years; range, 70–93) who received the same cementless plasma-sprayed porous titanium–hydroxyapatite stem were retrospectively evaluated after primary THA and HH to investigate stem survival, complications, and clinical and radiographic results. Results: Cumulative stem survival was 98.5% (95% CI, 96.4–99.4%; 91 hips at risks) with revision due to any reason as the end-point at 10-year follow-up (mean 8.6 years, range 4–12). No stem was revised due to aseptic loosening. The mean Forgotten Joint Score was 98.7. Radiographically, the implants showed complete osseointegration, with slight stress-shieling signs in less than 10% of the hips. Conclusion: The use of cementless stems was proven to be a reliable and versatile option even in elderly patients for elective THA and HH for femoral neck fracture. [ABSTRACT FROM AUTHOR]

Acetabular cup loosening is associated with pain, reduced function, and instability of the implant. If such event happens while the femoral implant is in a satisfactory position and is well fixed to the bone, isolated acetabular revision surgery is indicated. The aim of this single-center retrospective study was to evaluate the clinical and radiological results over the medium term (12-month follow-up mean 36, max 60) of isolated acetabular revisions surgery using a porous hemispheric revision shell matched with a cemented all-poly cup and large diameter femoral head (>32). 33 patients were enrolled. We collect any relevant data from the clinical board. Routine clinical and radiographic examinations were performed preoperatively; the postoperative follow-up was made at 1, 3, and 6 months and yearly thereafter. At the last available follow-up, we report satisfactory improvement of functional scores in all the patients; 2 patients (6.1%) showed thigh pain and only 4 hips (12.11%) presented mild groin pain; all the femoral components are well fixed and there were no potential or pending rerevisions. With bias due to the follow-up and to the retrospective design of the study, we report clinical, functional, and radiological satisfactory results. [ABSTRACT FROM AUTHOR]