Secondary degenerative disabling changes in the hip joint often develop in the long term after surgical treatment of hip fractures. A well-founded differential approach to the selection of endoprosthesis components and additional means of stabilizing bone fragments is necessary. Objective. To investigate changes in relative deformation values in a hip joint model with a acetabulum fractures 62–B1.3 type by AO/ASIF classification under the conditions of its endoprosthesis using various osteosynthesis options. Methods. A basic finite-element model of the pelvic girdle of a person with a fracture of the bottom of the cruciate ligament type 62-B1.3 (АО/ASIF) was developed, on which 7 variants of endoprosthesis of the left hip joint were modeled: without fracture (1); without osteosynthesis of fragments (2); fixation of a fragment of the acetabulum back wall with two screws (3), two screws and a bone plate (4), two screws and a bone plate with a Jumbo cup implantation (5); 5 case, long screw in the front column (6); option 5, long screws in the front and rear columns (7). Results. When using a large-sized Jumbo cup, the relative deformations of the bone regenerate in the center of the bottom of the KZ were reduced to 1.0 %, regardless of the osteosynthesis option. Around the free fragment of the short circuit, the largest relative deformations (3.0 %) were found in version 5 of the model. The use of long rods in the columns led to decrease in the relative deformations of the bone regenerate around the free fragment of the KZ to 2.0 %. Conclusions. Mathematical models proved that an increase in the number of osteosynthesis tools under the conditions of the total hip endoprosthesis replacement, 62-B1.3 (АО/ASIF) type KZ fracture leads to a decrease in the relative deformations of the bone regenerate along the entire fracture line. The use of a large-sized Jumbo cup makes it possible to reduce the level of relative deformations of the bone regenerate in the cent­ral part of the KZ.

Treatment of patients with acetabulum fractures (AF) remains a big challenge for orthopaedists and traumatologists. Suchfractures are known for their complications that lead to disability. Objective. To analyze the results of treatment of patientswith AF and complications that arise depending on the of the injury mechanism and the method of treatment, to evaluate the effectiveness available methods of preventing the development of these complications. Methods. A retrospective study wasdone on the basis of 89 AF patients analysis (age 17‒75 years, 22 women and 67 men) with different terms after the fracture.The majority of patients got primary care in other clinics. Diagnostic measures: clinical examination; X-ray examinationof the pelvis, that under conditions of acute injuries were supplemented with CT scan; ultrasound of abdominal cavity,chest X-ray, brain MRI, electroneuromyography of the lower limbs. Results. Most AF occurred as a result of traffic accidents.The most common types are A1 and B1 according to the classification of AO/ASIF. The system of skeletal traction has beenapplied often at the stage of primary treatment. During surgical treatment the Kocher-Langenbeck approach and osteosynthesis was mainly used to stabilize the posterior wall and acetabulum column. The typical complications of AF are coxarthrosis, femoral head aseptic necrosis despite the chosen treatment tactics. Their clinical manifestation with the hip impaired function occurred within a year after the trauma. Defined complications led to the need for total hip replacement in 67 (75.3 %) cases out of 89. In 8 patients, total hip replacement was performed in the acute period of injury and it was possible to restore the joint function with better early functional results compared to the rest of the patients. Conclusions. Primary total hip replacement in the case of AF is an effective treatment measure that gives the posibility restore the function of the hip joint in the shortest time and prevent the development of typical complications.

Acetabular fractures are known for their disabling outcomes, so the search for optimal treatment tactics is an actual problem for modern orthopedics and traumatology. Materials and methods. Randomized trials that reflect the results of acetabular fractures treatment depending on the method of treatment were analyzed. The literature was searched in the PubMed Central database. Hip joint is a complex two-component articulated system. Traumatic lesion of all elements of the joint creates the conditions for the development of a wide range of complications and secondary changes that must be taken into account at preoperative treatment. Aceta­bular fracture is an intra-articular injury, where the visualization methods have the prominent significance. Nowadays the treatment can be conservative and surgical. Surgical treatment can be divided into two areas: osteosynthesis and arthroplasty. Anatomical reposition and stable fixation of fragments, in the most of cases, is the key to a satisfactory functional result, but the development of post-traumatic changes in the joint nullifies the results of even perfect osteosynthesis, encourages repeated surgery and, finally, hip replacement. In recent years, primary arthroplasty has been successfully used to treat acetabular fractures, reducing inpatient and rehabilitation period, compared with osteosynthesis, preventing the possible development of secondary degenerative changes in the joint. Conclusions. Acute hip replacement is an effective treatment, however, the technical aspects of reliable fixation of the ace­tabular component of the implant are insufficiently substantiated and highlighted in actual literature and constitute significant research interest.