[Surgical repair of gluteus medius muscle in hip replacement surgery]. / Metodiki khirurgicheskogo lecheniia povrezhdenii srednei iagodichnoi myshtsy pri total'nom éndoprotezirovanii tazobedrennogo sustava.

Injury of gluteus medius muscle is a serious often complication after hip replacement surgery followed by pain, claudication and significant deterioration of the quality of life. Prevention of intraoperative injury of this muscle is especially relevant in young patients. Normal function of this muscle provides rapid rehabilitation and early postoperative recovery. However, hip replacement surgery through Hardinge's direct lateral approach is accompanied by fatty degeneration of gluteus medius muscle in 12-20% of cases. Moreover, two or more redo procedures lead to fatty degeneration of almost 70% of anterior and 40% of central muscular segment. Currently, there are many methods of surgical treatment of this complication including transosseous muscle fixation, endoscopic procedures, repair using Achilles tendon, gluteus maximus muscle, lateral head of quadriceps muscle and allografts. However, various publications devoted to this problem have certain disadvantages including short follow-up period, small sample size and often unsatisfactory outcomes. Therefore, the question of surgical repair of hip abductor function remains open.

[Hierarchy of spiral organization of skeletal structures. Interrelationship between structure and functions].

The objective of this review is to discuss the interrelationship between hierarchy of spiral organization of the structural elements of the skeleton and its mechanical characteristics with regard to functional-biological expediency. The following hierarchic levels of spiral organization of skeletal structures are defined: collagen chains, collagen molecules, microfibrils, fibrils, collagen fibers, osteon network and organization of osseous macrostructure responsible for torsion effect in weight bearing. This spiral organization creates the conditions, under which the directions of domineering forces in the bone usually do not coincide with the direction of the longitudinal crystallite axes. It causes shifting deformity between the adjacent crystallites. which should be taken into account alongside with distraction-compression deformity. These features form the basis of nano-level mechanism responsible for mechanical characteristics of bone tissue.