[Possible routes of infection in hip replacement]. / Vozmozhnye puti infitsirovaniya pri endoprotezirovanii tazobedrennogo sustava.

OBJECTIVE: To evaluate the probability of direct inoculation of pathogens into the bone bed by surgical instruments and implants. MATERIAL AND METHODS: The study included 22 patients who underwent surgery at the Vreden National Medical Research Center of Traumatology and Orthopedics. Mean age was 73.3±3.7 years. These patients underwent total hip replacement. Intraoperative skin scrapings within the wound edge were made. Pressure on the scalpel was applied in two fashions. In 10 cases, scraping was performed by minimally pressure on the skin (superficial contact). In 12 cases, scalpel was pressed with force (skin deformation to a depth of 3-4 mm). Next, microbiological analysis of scrapings was performed. RESULTS: There was no growth of microorganisms in samples obtained by minimal pressure on the scalpel. Analysis of 12 scrapings in the second group (tight contact simulating damage to the skin with surgical instruments) revealed growth of microflora in all cases. CONCLUSION: Contact of cutters, rasps and implants with skin can be a mechanism for direct inoculation of pathogens into the bone tissue and potentially cause periprosthetic infection.

Early outcomes of using custom-made augments in revision total hip arthroplasty.

INTRODUCTION: The continuing high demand for revision total hip arthroplasty (RTHA) requires not only additional economic costs, but also the search for new, effective methods to manage the reconstruction of acetabular bone loss. This study focuses on the assessment of the clinical and radiographic outcomes after RTHA using custom-made augments (CMA) in the short-term follow-up period. MATERIALS AND METHODS: We retrospectively analyzed the results of using CMAs in 19 patients (20 hips). The average follow-up period was 41.3 months. All surgery was performed on defect types III and IV as per the Gross and Saleh classification. RESULTS: There was a statistically significant difference when comparing the Oxford Hip Score before RTHA of 15.0 (Std. deviation-5.9) and after RTHA of 36.3 (Std. deviation-6.3) (p = 0.01). All implants were radiologically stable. CMA has demonstrated a good ability to restore position of hip centre of rotation (HCOR). In the postoperative period, two patients (2 hips) had dislocations. Only one of two patients underwent re-revision due to dislocation. CONCLUSION: Treatment of uncontained loss of bone stock in RTHA using CMA shows promising clinical and radiographic results at short-term follow-up period; however, dislocation rate is 10% in this study.

[Mid-term and long-term results of metal-on-metal total hip arthroplasty]. / Srednesrochnye i otdalennye rezul'taty éndoprotezirovaniia tazobedrennogo sustava s ispol'zovaniem pary treniia metall-metall.

OBJECTIVE: To assess mid-term and long-term results of metal-on-metal total hip arthroplasty. MATERIAL AND METHODS: There were 349 operations for the period 2006-2012 in our clinic. Sixty-four patients underwent a full examination. All patients underwent X-ray examination of the pelvis, MRI of hip joint with metal artifact reduction sequence (MARS). The concentration of cobalt and chromium metal ions was determined in blood serum. Each patient completed a questionnaire (Harris, Oxford, Womac, SF-36). 'Survival' of endoprostheses was calculated using the Kaplan-Meier method. RESULTS: According to the Oxford scale, 76.6% of patients had excellent clinical and functional outcomes, 10.9% - good, 9.4% - satisfactory, 3.1% - unsatisfactory. According to the Harris scale, 57.9% of patients had excellent results, 15.6% - good, 7.8% - satisfactory, 18.7% - unsatisfactory. Inclination less than 45 degrees was noted in 77.2% of acetabular components. It is optimal installation angle. According to MRI data, effusion was the main type of periprosthetic changes (16 cases). There were no periprosthetic changes in 33 cases. Pseudotumor was diagnosed in 5 cases. Mean concentrations of cobalt and chromium ions were 1.27 (13.57-0.12) and 0.59 (0.4-0.87) µg/l, respectively. Normal concentration of chromium ions was observed in all cases. Kaplan-Meier survival rate of endoprostheses was 89% (80-97%). CONCLUSION: There was no correlation between female sex, young age of patients and incidence of complications. It is necessary to exclude pseudotumor in case of pain syndrome and no signs of aseptic loosening of the components of the endoprosthesis.

[Additive technologies for complete recovery of joint function in revision endoprosthesis surgery (experimental trial)]. / Additivnaia tekhnologiia v polnom vosstanovlenii funktsii sustava pri éndoprotezirovanii (éksperimental'noe issledovanie).

AIM: Experimental analysis of the strength properties of integration of muscle tissue, tendons and ligaments, bone tissue into titanium highly porous materials prepared by using of additive technologies. MATERIAL AND METHODS: The study included 9 mature rabbits of the Chinchilla breed. Both posterior paws and latissimus dorsi muscles (36 specimens) were used. Titanium models (Ti-6-Al-4-V, 'Rematitan', Germany) were made by additive technologies with preliminary prototyping, the prototypes had a highly porous mesh structure. RESULTS: It was developed experimental model of functional bone defect involving points of attachment of the muscle and ligaments. Strength of attachment of muscles to highly porous implants was 145 H vs. 31 H for standard models. Tensile strength for fixation to bone tissue was 84 H vs. 152 H in the main group. CONCLUSION: It was found integration of soft tissues and bones into highly porous titanium implants prepared with additive technologies. Fixation strength significantly exceeds that for standard models.

[Management of complex acetabulum fractures and their consequences]. / Lechenie slozhnykh perelomov vertluzhnoi vpadiny i ikh posledstvii.

In the structure of pelvic bone injuries, acetabular fractures are the most complex type and, according to different authors, account for up to 20% [1]. The severity of these injuries is confirmed by the fact that early descriptions of acetabular fracture were based only on the results of autopsies of patients who had suffered a combined injury. Thus, as early as 1788, Callisen reported an acetabular fracture, but without a detailed description of the nature of the injury. In 1909, Schroeder provided a detailed report of 49 cases of acetabular fractures reported in the literature. Most of them were described during autopsies of patients who died from complications associated with hemorrhagic shock or the onset of sepsis [2]. Fractures of the acetabulum in most observations are the result of high-energy impacts, usually as a result of traffic accidents; therefore, the mechanism of injury determines the combined and multiple nature of the injuries in the victims. A significant proportion of acetabular fractures (up to 60%) are accompanied by fragment displacement and dislocation of the femoral head, in which the most severe tissue changes occur [3].

PREVENTION OF VENOUS THROMBOEMBOLIC COMPLICATIONS IN REPLACEMENT ARTHROPLASTY PERFORMANCE IN PATIENTS WITH ASSOCIATED CHRONIC DISEASES OF LOWER EXTREMITIES VEINS.

A number of patients with problems of major joints increases every year. These patients need the replacement arthroplasty. The rate of thrombotic complications rises in given category of patients simultaneously with the increase of the number of performed operations. There weren't well-defined instructions of management of the patients with associated chronic vein diseases at the preparation period for arthroplasty performance in spite of the presence of clinical recommendations for prevention of thromboembolic complications. The authors analyzed the experience of management of such patients and presented these data for doctors from polyclinic and hospitals in order to apply the common treatment strategy.

POSSIBILITIES OF MODERN TECHNOLOGIES OF VISUALIZATION AND MODELING IN ORTHOPEDICS AND THEIR ROLE IN DEVELOPMENT OF INDIVIDUAL CONSTRUCTIONS IN HIP ARTHROPLASTY.

The article presents the authors' experience. Medical visualization is applied in orthopedics on all stages such as diagnostics, treatment planning and control of the results. Modern approaches in instrumental diagnostics and specialized application-dependent software allowed a new qualitative level of orthopedics and medical care in different areas of medicine. Modern technologies gave a lot of opportunities to doctors in order to improve diagnostics at higher level, make an individual planning of operations and built individual implants, when it wasn't possible to use standard constructions.