RU-2861549-C1 - METHOD FOR OSTEOSYNTHESIS OF FEMORAL NECK FRACTURE

RU2861549C1RU 2861549 C1RU2861549 C1RU 2861549C1RU-2861549-C1

Abstract

FIELD: medicine. SUBSTANCE: present invention relates to traumatology and orthopaedics, and can be used for osteosynthesis in femoral neck fractures. Wires are inserted through separate punctures in the skin. At the first stage, a guide wire for the distal screw is inserted, the insertion point of the wire being determined 2-4 cm distal to the lower edge of the greater trochanter with an inclination of the wire at an angle of 150-165° to the posterior third of the femoral head. At the second stage, a middle guide wire is inserted with the entry point in the posterior third of the lateral cortical layer of the femur, 3-4 cm proximal to the lower edge of the greater trochanter, with an anterocranial inclination of 130-135° to the diaphyseal axis. After that, a proximal wire is inserted with the entry point in the posterior third of the lateral cortical layer at a distance of 1.5-2.0 cm proximal to the entry point of the middle wire and parallel to it, the guide wire being directed into the upper anterior part of the femoral head. The screws are positioned, and drilling is performed along the middle and upper guide wires using a cannulated drill with a diameter of 5.0 mm. After that, the middle hole for the screw in the lateral cortical layer is drilled again using a cannulated drill with a diameter of 7.3 mm, then the middle and upper screws are inserted, forming interfragmentary compression. Drilling is performed for the lower guide wire using a cannulated drill with a diameter of 5 mm, then this hole is drilled again using a cannulated drill with a diameter of 7.3 mm, and the lower screw is installed. EFFECT: reliability of osteosynthesis by simplifying the surgical technique, reducing operation time, and reducing soft tissue trauma. 1 cl, 8 dwg, 2 ex

Inventors

Nazarov Dilovar Sadulloevich
Ajrapetov Georgij Aleksandrovich
Zagorodnij Nikolaj Vasilevich
Lukin Maksim Prokopevich
MIRONOV ANDREJ NIKOLAEVICH
Burkov Dmitrij Vladimirovich
Karpovich Nikolaj Ivanovich
Karpovich Andrej Nikolaevich

Dates

Publication Date: 20260505
Application Date: 20250926

Claims (1)

A method of osteosynthesis of a femoral neck fracture that involves inserting pins through separate punctures in the skin; at the first stage, a guide pin is inserted for the distal screw, with the entry point of the pin being determined at 2-4 cm distal to the lower edge of the greater trochanter with a pin inclination of 150-165° to the posterior third of the femoral head; at the second stage, a middle guide pin is inserted with an entry point in the posterior third of the lateral cortical layer of the femur 3-4 cm proximal to the lower edge of the greater trochanter, with an antero-cranially inclination of 130-135° to the diaphyseal axis; after this, a proximal pin is inserted with an entry point in the posterior third of the lateral cortical layer at a distance of 1.5-2.0 cm proximal to the entry point of the middle pin and parallel to it, with the guide pin directed into the upper anterior part of the femoral head; then, the screws are positioned and drilling is performed along the middle and upper guide pins using a cannulated drill 5.0 mm in diameter, after which the middle screw hole in the lateral cortex is drilled again with a cannulated drill with a diameter of 7.3 mm, then the middle and upper screws are inserted, forming interfragmentary compression, after this, drilling is performed for the lower guide pin using a cannulated drill with a diameter of 5 mm, then this hole is drilled again with a cannulated drill with a diameter of 7.3 mm and the lower screw is installed.

Description

The present invention relates to medicine, namely to traumatology and orthopedics, and is intended for osteosynthesis in case of a fracture of the femoral neck. In modern traumatology, there are various treatment methods for hip fractures for both young and elderly patients. A method of osteosynthesis in case of intra-articular fracture of neck of femur is known (patent no. RU 2122368 C1, published on 27.11.1998), including connection of bone fragments by means of several pins fan-shaped introduced into head, bending of ends of pins and fastening of bent ends of pins together by a cap, characterized in that a cap is used, made in the form of a loop with the possibility of passing a pin through it, in one plane with it an extension element and on its other end two mutually oppositely directed elastic elements with the possibility of fastening them together, the free ends of pins are first bent upwards, except for one pin, which is passed through a loop, and then the bent part of this pin is placed above the extension element, the bent ends of the remaining pins are turned in one direction and captured by elastic elements, which are fastened together. Currently, total hip arthroplasty is the gold standard for active elderly patients with displaced femoral neck fractures. However, there are also patients with a high operative risk for major surgery due to the presence of comorbidities, and total hip arthroplasty is contraindicated in these patients. The current generally accepted method of fixing a femoral neck fracture uses three parallel cannulated screws. This method involves placing the patient on an orthopedic table, applying traction to the limb, and performing a closed reduction. Under image intensifier guidance, after reduction, three parallel pins are initially inserted into the femoral neck, forming an inverted triangle in the region of the greater trochanter. The pins are then drilled using a 5.0 mm drill bit. After preliminary screw length measurements, cannulated screws of the appropriate size are inserted through the inserted pins. Leadbetter, Guy W. MD (1893-1945). A Treatment for Fracture of the Neck of the Femur. Clinical Orthopedics and Related Research 399():p 4-8, June 2002. These methods have a number of drawbacks. The described fixation methods do not always provide adequate fixation strength, which is especially true in patients with osteoporosis, as unsatisfactory results may develop later. The interfragmentary compression of these structures is often insufficient and, therefore, unable to ensure stability in osteoporotic bone. Furthermore, the structures can sometimes be unstable in varus positions of the fragments. Popular traditional methods of femoral neck fixation using three cancellous screws placed parallel to each other and parallel to the femoral neck axis are associated with poor results in 20-42% of cases (e.g., patent No. 2,687,754 C1, published May 16, 2019). The high failure rate of traditional screw fixation methods can be explained by a number of biomechanical deficiencies. Lack of structural stability under varus loads. A femoral neck fracture is subjected to strong shear forces due to the angular, helical architecture of the proximal femur. To ensure resistance to shear forces in the presence of osteoporosis, screws must be firmly fixed in the distal fragment at at least two points. This requirement is not met by traditional screw fixation methods, in which the entry points of three screws are located in or close to the thin cortex of the greater trochanter. Screws are often placed in soft cancellous bone near the femoral neck axis, without any cortical support. Even if the distal screws (one or two) are placed close to the distal cortex of the femoral neck, they lack a second strong anchor. Their second anchor is the thin lateral cortex of the greater trochanter—their entry point. This design can rely solely on interfragmentary compression created by tightening the screws during surgery, but achieving compression depends on the strength of the cancellous bone. This leads to a high failure rate in cases of osteoporosis. The inability to move the screw entry point distally into the hard diaphyseal cortex while simultaneously placing three parallel screws. The proposed method overcomes the shortcomings of similar methods through the use of a biplane, obtuse-angled arrangement of three screws. Providing two stable anchor points for the implants and the obtuse angle at which they are positioned allow for successful weight transfer from the head fragment to the diaphysis due to the strength of the screws, while minimizing the patient's bone quality. The screw placement allows them to slide under load with minimal risk of displacement. The fracture consolidation results achieved with this method are significantly more successful than those achieved with traditional fixation methods. This technique ensures reliable fixation, early rehabilitation, and excellent long-term resul