RU2804578C1 - Method for preparing anterior cruciate ligament autograft from tendon of proprietary patella ligament with two bone blocks - Google Patents

Abstract

FIELD: medicine; traumatology; orthopedics.

SUBSTANCE: invention can be used to prepare an autograft of the anterior cruciate ligament from the tendon of the patellar ligament with two bone blocks. The middle third of the tendon of the patellar ligament 1 cm wide is taken. In this case, the proximal bone block from the patella is taken no more than 1 cm long and 0.5 cm thick. Two transverse through channels are formed in the proximal bone block. Then the proximal bone block is thrown through the loop of a self-tightening button fastener, turned 180° and placed on the anterior part of the patellar tendon. A non-absorbable thread is passed from below the proximal part of the graft, the ends of the thread are passed on the right and left of the graft to the top of the bone block and, using a needle, are passed through the distal transverse through channel of the proximal bone block and the thickness of the tendon. Then the ends of the threads are passed to the right and left of the graft to the top of the bone block, connected and, using a needle, passed through the proximal transverse through channel of the proximal bone block and the thickness of the tendon. Next, the ends of the thread are once again moved to the top of the bone block of the proximal part of the graft, connected and, using a needle, passed through the thickness of the tendon at the point of its bend to the lower surface of the graft, the threads are tightened and knots are applied. Next, a centrally located longitudinal channel equal to the length of the bone block is formed in the distal bone block from the tibial tuberosity. The thickness of the patellar ligament tendon is sutured proximal to the bone block in the plane of its width, then equal ends of the thread are passed on the right and left to the top of the graft, after which the ends are connected and passed through the longitudinal channel of the distal bone block outward.

EFFECT: method improves the outcomes of surgical treatment of anterior cruciate ligament ruptures by preparing the graft with the ability to provide more reliable fixation of the graft in the bone canal, reducing the risk of developing a patellar fracture and autograft failure, eliminating the risk of complications associated with the use of screw fixation due to the combination of techniques of the claimed invention.

1 cl, 11 dwg, 1 ex

Description

Field of technology to which the invention relates

The invention relates to medicine, namely to traumatology and orthopedics, and can be used to prepare an autograft of the anterior cruciate ligament from the tendon of the patellar ligament.

State of the art

A method of preparing an autograft for plastic surgery of the anterior cruciate ligament is known from the prior art (RU 2727744 C1, INCHT, 07/23/2020), in which, before harvesting autotendons, the required length and thickness of the autograft, formed from two tendons, semitendinosus and gracilis, is arthroscopically determined, and the collection is performed semitendinosus and gracilis tendons simultaneously, preserving the common tendon pedicle, then on a preparation table, a single tendon is formed from the tendons separated on the common tendinous pedicle: folded into several bundles in accordance with the previously determined individual length and thickness of the autograft.

The disadvantage of this method is the use of an autograft without bone blocks, which increases the time of graft integration in the bone canal and reduces the reliability of its fixation.

There is also a known method for preparing an autograft for plastic surgery of the anterior cruciate ligament with two bone blocks (RU 2432135 C1, Suchilin I.A., October 27, 2011), in which one of the bone blocks is made at two-thirds of its length in the shape of a truncated cone with the base in place attachment of the ligament, the diameter of which is no more than 1 mm greater than the diameter of the apex, the remaining one third of the bone block at its free end is made of a cylindrical shape, the diameter of which corresponds to the diameter of the apex of a truncated cone.

The disadvantage of this method is that a bone block up to 3 cm long and at least 1 cm thick is formed from the patella, which increases the risk of developing postoperative patellar fractures.

From the article “Plasty of the anterior cruciate ligament with a bone-tendon-bone graft with press-fit fixation: compromise or alternative?” (Suchilin I.A. et al. Bulletin of the Volgograd Scientific Center of the Russian Academy of Medical Sciences. 2008, 4, pp. 37-40) there is a known method of preparing an autograft for plastic surgery of the anterior cruciate ligament, in which the autograft is taken from the middle third of the patellar ligament with two bone blocks, In this case, the graft width was 10 mm; bone blocks 20 mm long were given a semi-cylindrical shape during processing.

In addition to the disadvantages indicated for RU 2432135, in this case, a graft formed as indicated in the article implies fixation with interference screws, which increases the risk of complications such as the formation of a synovial cyst, bone resorption and expansion of the bone canal.

The closest analogue is the method of preparation for plastic surgery of the anterior cruciate ligament from the tendon of the patellar ligament with two bone blocks, in which the autograft is formed from the middle third of the patellar ligament 10 mm wide. The bone block obtained from the femur has a rectangular shape with dimensions of 5x10x15 mm with two transverse bone channels through which the EndoButton cortical fixation threads are passed, the second bone block has a cylindrical shape with dimensions of 10x15 mm (TAKETOMI S. et al. Secure fixation of femoral bone plug with a suspensory button in anatomical anterior cruciate ligament reconstruction with bone-patellar tendon-bone graft. Joints, 2015, 3(3), pp. 102-108).

The disadvantage of the prototype is the use of a conventional cortical fixator, which does not allow correcting the insufficient tension of the graft, and standard suturing of the distal bone block with threads through the channels contributes to their rubbing during screw fixation with the further impossibility of adequate tension of the graft up to complete failure of the graft.

The objective of the claimed invention is to develop a method for preparing an autograft to improve the outcomes of surgical treatment of anterior cruciate ligament ruptures.

Disclosure of the invention

The technical result of the claimed invention is to ensure reliable osseointegration and fixation of the autograft in the bone canal due to the location of a bone block of a certain size, with the spongy side to the wall of the femoral canal, which ensures the prevention of the development of postoperative fractures of the patella. In addition, suturing the distal part of the graft allows one to avoid chafing of the threads during the process of fixing the graft with a screw, since there is no direct contact between the threads and the screw, and also, the use of the technique of suturing the graft allows the use of hybrid fixation (screw together with a button) and additional tension of the graft if necessary.

The technical result is achieved through the following techniques.

The middle third of the tendon of the patellar ligament, 1 cm wide, is taken with a bone block from the patella at the proximal end of the graft and from the tibial tuberosity at the distal end of the graft. In this case, a proximal bone block from the patella is taken no more than 1 cm long and 0.5 cm thick, which helps reduce the risk of developing postoperative patellar fractures. Next, two transverse through channels are formed in the proximal bone block, located centrally and at an equal distance from the ends of the bone block and from each other. Then the proximal bone block is thrown through the loop of a self-tightening button clamp, rotated 180° and placed on the anterior part of the patellar tendon so that the posterior cancellous part of the bone block remains outside, which will facilitate its integration into the walls of the femoral canal. A non-absorbable thread is passed from below the proximal part of the graft, then the ends of the thread are passed on the right and left of the graft to the top of the bone block, then the ends of the thread are passed through the distal transverse through channel of the proximal bone block and the thickness of the tendon using a needle, bringing them to the lower part of the graft, the threads are tightened. Then the ends of the threads are again passed along the sides of the graft to the top of the bone block, after which the ends of the thread are connected and, using a needle, passed through the proximal transverse through channel of the proximal bone block and the thickness of the tendon. At the end, the ends of the thread are once again moved to the top of the bone block of the proximal part of the graft, the ends of the thread are connected and, using a needle, passed through the thickness of the tendon at the point of its bend to the lower surface of the graft, the threads are tightened and knots are applied. Next, in the distal bone block from the tibial tuberosity, a centrally located longitudinal channel is formed, equal to the length of the bone block, the thickness of the patellar ligament tendon is sutured with a non-absorbable thread proximal to the bone block in the plane of its width, then equal ends of the thread are passed on the right and left to the top of the graft, after which the ends connect and pass through the longitudinal canal of the distal bone block outward.

Brief description of the drawings.

The claimed invention is illustrated in Fig. 1-9.

Figure 1 shows an autograft with two bone blocks: proximal dimensions 1 x 0.5 x 1 cm, distal dimensions 1 x 2.5 x 1 cm.

Figure 2 shows the location of the loop of a self-tightening button fastener.

Figure 3 demonstrates the location of the distal bone block relative to the loop of the self-tightening button fastener.

Figures 4-6 show a diagram of suturing the proximal part of the graft.

Figures 7, 8 show a diagram of suturing the distal part of the graft.

Figure 9 shows a prepared autograft of the anterior cruciate ligament from the tendon of the patellar ligament.

Figure 10 shows the tendon of the patellar ligament with bone blocks, taken using the proposed method.

Figure 11 shows an MRI of the knee joint, which visualizes the consistency of the autograft, and also marks the integration of the bone blocks of the graft into the bone canals without their expansion.

Implementation of the invention.

Using standard anterior or two mini-invasive approaches, the middle third of the tendon of the patellar ligament 1 cm wide is harvested with a bone block from the patella at the proximal end of the graft and from the tibial tuberosity at the distal end. A special feature of graft harvesting is that a bone block no more than 1 cm long and 0.5 cm thick is taken from the patella, which helps reduce the risk of developing postoperative patellar fractures. A bone block from the tibial tuberosity is taken of a standard size, about 2.5 cm in length and about 1 cm in thickness (Fig. 1).

After harvesting the graft on the preparation table, the tendon is cleared of adipose tissue, the bone blocks are cleared of protruding bone areas and compacted to the required thickness using a sealant from the manufacturer Arthrex.

The first step is to prepare the proximal end of the graft, which will subsequently be immersed in the femoral canal. To do this, two transverse through channels are formed in a bone block from the patella using a 2 mm drill, which are located centrally and at an equal distance from both the ends of the bone block and from each other. A loop of a self-tightening button clamp is placed immediately distal to the bone block (Fig. 2), after which the latter is thrown through this loop, turned 180° and placed on the anterior part of the patellar tendon, while the posterior cancellous part of the bone block remains outside, which will facilitate its integration into the walls of the femoral canal (Fig. 3).

A non-absorbable thread measuring 2 UPS is passed from below the previously formed proximal part of the graft, after which the ends of the thread are loaded into a needle, passed through the distal of the previously formed 2 mm channels, including passing through the thickness of the tendon, and tightened, forming a kind of “noose” ( Fig. 4). Next, the ends of the thread are again passed to the right and left of the graft to the top of the bone block, immersed with a needle into the proximal canal and tightened. Finally, the ends of the thread are once again moved to the top of the bone block of the proximal part of the graft, but this time the ends of the thread are passed through the thickness of the tendon at the point of bend (Fig. 5), tightened and knots are applied, fixing the suturing thread (Fig. 6).

The second stage is to form the distal part of the graft, which will subsequently be immersed in the tibial canal. To do this, a centrally located longitudinal channel is formed in a bone block from the tibial tuberosity using a 2 mm drill along the entire length of the bone block. Using a non-absorbable thread of size 2 UPS, at a distance of 4-5 mm proximal to the bone block, the thickness of the patellar tendon is sutured in the plane of its width (Fig. 7). Two ends of the thread, equal in length, are passed over the thickness of the tendon, wrapping it on both sides, and immersed in a previously formed 2 mm channel (Fig. 8).

Button fixation of the femoral part of the graft allows for tight contact of the graft with the canal walls on all sides, which improves graft integration, while eliminating complications associated with classical screw fixation (wide bone canals, bone cysts).

The suturing scheme for the distal part of the graft allows one to avoid possible chafing of the threads during the process of fixing the graft with a screw, since there is no direct contact between the threads and the screw, which also allows the use of hybrid fixation (screw together with a button), since the threads will not be compromised by the screw. In this case, when the screw holds the bone block directly, and the cortical button holds the threads that directly stitch the tendon itself, the hybrid technique will provide more reliable fixation of the graft.

In addition, if the graft tension is insufficient, traction is performed on the threads of the femoral button fixator, which leads to additional tension due to a decrease in the fixator loop. In turn, the ability to achieve adequate tension of the graft, strong fixation of the graft, and full contact of the graft with the bone canals provide complete stability of the knee joint, which leads to improved treatment results.

Clinical example

As an example, we give a clinical observation of patient N., 29 years old. Diagnosis: Post-traumatic anterior instability of the knee joint. Anterior cruciate ligament rupture. The knee injury occurred 8 weeks before the consultation while playing football. At the time of treatment, he complains of a feeling of instability of the knee joint, pain during physical activity. On examination: he moves independently without additional support, range of motion in the knee joint is 5-0-140. Symptoms of Baikov, McMurray, Thesalian test are negative. The anterior drawer test and Lachman test are positive (+++). Rear drawer test negative. Axial loading is painless. No vascular, motor or sensory disorders were detected in the distal parts of the limb at the time of examination. An MRI of the knee revealed a complete rupture of the anterior cruciate ligament.

Surgical intervention was performed in the scope of arthroscopic autoplasty of the anterior cruciate ligament using the tendon of the patellar ligament with bone blocks, taken (Fig. 10) and prepared according to the proposed method, while the proximal bone block is formed with a length of 1 cm and a thickness of 0.5 cm.

The postoperative period was without complications, the rehabilitation period proceeded according to the standard protocol for ACL autoplasty.

At 6 months from the date of surgery, an MRI of the knee joint was performed, which visualized the consistency of the autograft, and also noted the integration of the bone blocks of the graft into the bone canals without their expansion (Fig. 11). After 12 months, the patient fully recovered and returned to sports.

Claims (1)

A method for preparing an autograft of the anterior cruciate ligament from the tendon of the patellar ligament with two bone blocks, including taking the middle third of the tendon of the patellar ligament 1 cm wide with a bone block from the patella at the proximal end of the graft and from the tibial tuberosity at the distal end of the graft, characterized in that a proximal bone block from the patella is taken no more than 1 cm long and 0.5 cm thick, then two transverse through channels are formed in the proximal bone block, located centrally and at equal distances from the ends of the bone block and from each other, then the proximal bone block is thrown through a loop of a self-tightening button fastener is turned 180° and placed on the anterior part of the patellar tendon so that the posterior spongy part of the bone block remains outside, then a non-absorbable thread is passed from below the proximal part of the graft, then the ends of the thread are passed on the right and left of the graft to the top of the bone block, then the ends of the thread are passed through the distal transverse through channel of the proximal bone block and the thickness of the tendon, bringing them to the lower part of the graft, the threads are tightened, then the ends of the threads are passed to the right and left of the graft to the top of the bone block, after which the ends of the thread are connected and passed through the proximal transverse through channel proximal bone block and the thickness of the tendon, after which the ends of the thread are once again moved to the top of the bone block of the proximal part of the graft, the ends of the thread are connected and passed through the thickness of the tendon at the place of its bend to the lower surface of the graft, the threads are tightened and knots are applied, then in the distal bone block from The tibial tuberosity forms a centrally located longitudinal channel, equal to the length of the bone block, the thickness of the patellar tendon is sutured with a non-absorbable thread proximal to the bone block in the plane of its width, then equal ends of the thread are passed on the right and left to the top of the graft, after which the ends are connected and passed through the longitudinal channel distal bone block outward.