CN104107085B - A component connecting rod with the function of precise and sustained drug dose release - Google Patents

Abstract

A kind of component connecting rod with the accurate slow-release function of drug dose, relate to the device being used for the treatment of bone or joint, particularly relate to a kind of controllable sustained-release medicine carrying parts for spinal internal fixation system, the body of rod comprising hollow and the first locking device being connected to body of rod two ends and the second locking device, the body of rod arranges medicine carrying room, air rammer and air pressure pushing component; The tail end of the body of rod is provided with medicine liquid channel and medicament slow release duct, and medicament slow release duct is communicated with medicine liquid channel, forms medicinal liquid release channel; Control assembly is released by medicinal liquid in medicine carrying room, controllably closes or is communicated with medicine liquid channel.Use body temperature-memorial alloy control as startup and release control device, do not need extra power supply, high and the function-stable of space availability ratio, simple and reliable for structure, the accurate slow-release function of medicine can be realized, meet the drug effect concentration needs of different pharmaceutical, use closed medicine carrying room to store medicinal liquid, sealed storage before drug release, can not be affected by external environment.

Description

A component connecting rod with the function of precise and sustained drug dose release

technical field

The invention relates to a device for treating bones or joints, in particular to a drug-loaded high-pressure pneumatic slow-release component connecting rod used in a spinal internal fixation system.

Background technique

At present, topical medication has gradually become a research hotspot, especially local sustained-release medication, which can maintain a certain effective blood drug concentration in local lesions, and can also achieve the best drug effect for some tissues with poor blood supply. How to slowly release the drug to the local tissue is a key issue, and the use of implants is one of the main trends to solve this problem.

The Chinese invention patent "A Vascular Stent with Drug-Loading Groove" (Chinese Invention Patent No.: ZL200910157519.X Authorized Announcement No.: CN101940508B) discloses a vascular stent with a drug-loaded groove, including multiple support rods and multiple Two connecting rods, the supporting rods and the connecting rods are longitudinally arranged to form a tubular shape, and the adjacent supporting rods are connected by the connecting rods; the supporting rods are provided with drug-loading grooves, and the drug-loading grooves It includes a top opening, and the drug-loading tank also includes a bottom surface formed by intersecting with the support rod and two left and right sides; the support rod has a side drug release opening on at least one side of the drug-loading tank. This invention patent places the drug on the support rod provided with the drug-loading groove, so that it has the effect of support and drug sustained release, and can be used to improve the effect of local vascular restenosis.

For spinal lesions such as osteomyelitis, spinal tumors, and tuberculosis, the treatment effect through intravenous injection is poor, mainly because the concentration of the drug reaching the lesion is too low, and local application can avoid the first pass effect and local microcirculation Poor and many other factors, to achieve the best therapeutic effect. For such spinal lesions, in order to perform cone reduction and fixation on the fractured or diseased spine, it is usually necessary to implant a spinal internal fixation system to rebuild the mechanical stability of the spine. Spinal fixation systems usually include a set of pedicle screws, lateral connecting rods, and transverse connecting rods. For ease of description, in the following description of the present invention, the pedicle screw is referred to as the connected part 11, the connecting rod 12 connecting each pedicle screw in the spinal internal fixation system, and the connecting rod 12 connected between each connecting rod 12. Transverse connecting rods 15 are collectively referred to as component connecting rods. In practical application, the number of pedicle screws and component connecting rods is determined according to the number of vertebral bodies affected. Each pedicle screw of the spinal internal fixation system is connected to each other through multiple component connecting rods to form a stable support frame and strengthen the pedicle. For screw stability, see Figure 1.

Chinese utility model patent "antimicrobial peptide-loaded slow-release bone screw" (Chinese utility model patent number: ZL200920126446.3 authorized announcement number: CN201404282Y) discloses a slow-release bone screw loaded with antimicrobial peptide, including a bone screw. Composed of a head and a screw shaft, it is characterized in that: the outer surface of the screw head and the screw shaft is covered with an antimicrobial peptide slow-release layer, and the bone screw can release β-defensin early from the inside to the outside within a certain period of time -1～3 or lactoferrin 1-11, so that the screw has a strong ability to resist infection and inhibit the formation of bacterial biofilm.

At present, there are researches on the technical scheme of injecting medicine through the hollow pedicle screw by connecting the hollow pedicle screw on the connecting rod. Chinese utility model patent "Hollow expandable pedicle screw capable of carrying particles" (Chinese utility model patent number: ZL201120497873.X authorized announcement number: CN201404282Y) discloses a hollow expandable pedicle screw capable of carrying particles. Silver rod adsorption and bone cement containing chemotherapeutic drugs are built into the expansion hollow screw, so that nuclear radioactive substances and chemotherapeutic drugs can be combined with the bone cement at the expanded part of the screw for the treatment of spinal tumors. However, the therapeutic effect of chemotherapy drugs combined with bone cement needs further study.

However, the existing methods of combining pedicle screws with drugs have the following defects:

1. After the drug is inserted into the hollow pedicle screw, the sustained release cannot be controlled, resulting in excessive local blood drug concentration and being metabolized by the body quickly. In addition, the scope of action of screw sustained release is narrow, and the concentration may be uneven, requiring internal fixation devices to provide more sites to release drugs at the same time (such as the decompression area behind the spine)

2. The existing drug-loaded stents and drug-loaded screws cannot precisely control the slow-release rate, and cannot meet the needs of the concentration of different drugs.

3. The outer layer of the technical solution of the drug-loaded coating is coated with slow-release drugs and is also easily affected by the external environment.

Contents of the invention

The object of the present invention is to provide a component connecting rod with the function of precise and sustained release of drug doses, which can activate the high-pressure pneumatic drug-loaded slow-release component through the body temperature-memory alloy control, and store the drug pre-set in the component connecting rod, Slowly injected into the vertebral body of the spine to solve the problem of maintaining the effective therapeutic concentration of the drug within a certain treatment cycle and improve the curative effect of spinal surgery-related diseases.

The technical solution adopted by the present invention to solve the problems of the technologies described above is:

A component connecting rod with the function of precise sustained release of drug doses, comprising a hollow rod body and a first locking device and a second locking device connected to both ends of the rod body, the component connecting rod passes through the first locking device and the second locking device The second locking device is connected to the connected part, which is characterized in that:

The middle section of the rod body is provided with a drug-loading chamber with a cylindrical cavity structure, and a pneumatic piston is arranged inside the drug-loading chamber, and the outer periphery of the pneumatic piston is airtightly matched with the inner wall of the drug-loading chamber;

The head end of the rod body is provided with a pneumatic push assembly, and the air push assembly is pneumatically connected to the pneumatic piston, which can push the pneumatic piston to move in the axial direction;

The tail end of the rod body is provided with a liquid medicine channel and a drug sustained-release channel, and the drug sustained-release channel is a group of fine through holes distributed at the tail end of the rod body and connected with the liquid medicine channel. The channels are connected to form a liquid medicine release channel;

The end of the drug-loaded chamber is provided with a drug solution release control component, and the drug-loaded room is controllably closed or communicated with the drug solution channel through the drug solution release control component.

A preferred technical solution of the component connecting rod with the function of accurate and sustained release of drug doses in the present invention is characterized in that the pneumatic push assembly includes a spherical air bag, a normally closed air valve and a first body temperature-memory alloy control; The spherical airbag is a closed sphere filled with an inert gas higher than atmospheric pressure, and the air outlet of the spherical airbag is hermetically closed by a normally closed air valve; when the temperature sensed by the first body temperature-memory alloy control is higher than the memory temperature, the first The body temperature-memory alloy control pushes open the normally closed air valve, releases high-pressure gas to push the pneumatic piston to move axially, and discharges the liquid medicine stored in the medicine-loading chamber under the action of air pressure.

A better technical solution of the component connecting rod with the function of accurate and sustained drug dose release in the present invention is characterized in that the drug release control assembly includes a drug liquid valve and a second body temperature-memory alloy control; The two ends of the medicine chamber are respectively closed by the pneumatic piston and the liquid medicine valve to form a closed liquid medicine storage space; when the temperature sensed by the second body temperature-memory alloy control is higher than the memory temperature, the second body temperature-memory alloy control opens the The drug solution valve described above communicates the drug-loading chamber with the drug solution channel, and the drug solution in the drug-loaded room enters the drug solution channel under the push of the pneumatic piston, and passes through the various drugs distributed at the tail end of the rod body. Slow-release channel release.

An improved technical solution of the component connecting rod with the function of accurate and sustained release of drug doses according to the present invention is characterized in that the first body temperature-memory alloy control is a spring member made of body temperature-shape memory alloy; the body temperature - the memory temperature of the shape memory alloy spring part corresponds to normal body temperature; when the temperature of the body temperature - the shape memory alloy spring part is lower than the body temperature, the shape memory alloy spring part is in the memory shape of the folded state, and the The normally closed air valve remains in the closed position; when the temperature of the body temperature-shape memory alloy spring part is equal to or higher than the temperature of human body body temperature, the body temperature-shape memory alloy spring part is in the memory shape of the stretched state, and the normal The air-closing valve is in an open position under the driving force of the body temperature-shape memory alloy spring.

A preferred technical solution of the component connecting rod with the function of accurate and sustained release of drug doses in the present invention is characterized in that the second body temperature-memory alloy control is a spring member made of body temperature-shape memory alloy; the body temperature - the memory temperature of the shape memory alloy spring part corresponds to normal body temperature; when the temperature of the body temperature - the shape memory alloy spring part is lower than the body temperature, the shape memory alloy spring part is in the memory shape of the folded state, and the The liquid medicine valve remains in the closed position; when the temperature of the body temperature-shape memory alloy spring is equal to or higher than the temperature of the human body, the body temperature-shape memory alloy spring is in the memory shape of the stretched state, and the medicine The liquid valve is in the open position under the driving force of the body temperature-shape memory alloy spring.

The beneficial effects of the present invention are:

1. The connecting rod of the component with the function of accurate and slow release of drug dosage of the present invention uses the air pressure push assembly and the liquid medicine release control assembly as the control device, controls the push speed through the mechanical air pressure system, and controls the concentration of the liquid medicine stored in the medicine loading chamber, It can realize the precise and sustained release function of drugs, so as to meet the needs of drug concentration of different drugs.

2. The connecting rod of the component with the function of accurate and slow release of drug dosage of the present invention uses body temperature-memory alloy control as the start and release control device, does not require external energy supply, has high space utilization rate, stable function, and simple and reliable structure.

3. The component connecting rod with the function of accurate and slow release of drug dosage of the present invention uses a closed drug-loading chamber to store the drug solution, and the drug is stored in a sealed manner before release, so that it will not be affected by the external environment.

4. Compared with simple pedicle screw drug slow release, coupled with connecting rod drug slow release can make the drug concentration in the lesion more uniform.

Description of drawings

Fig. 1 is a schematic diagram of the basic composition of an existing spinal internal fixation system;

Fig. 2 is a schematic structural view of the component connecting rod with the function of precise sustained release of drug doses of the present invention;

Fig. 3 is a top view of the component connecting rod with the function of accurate and sustained release of drug doses according to the present invention;

Fig. 4 is a schematic view of the connection relationship of the spinal internal fixation system using the component connecting rod of the present invention.

In the figure, 11-connected part, 12-connecting rod, 13-first locking device, 14-second locking device, 15-transverse connecting rod, 16-member connecting rod, 101-high pressure air bag, 102-normal Air-closing valve, 103-first body temperature-memory alloy control, 104-pneumatic piston, 105-medicine fluid valve, 106-second body temperature-memory alloy control, 107-medicine loading chamber, 108-medicine solution channel, 109-medicine delay release hole.

detailed description

In order to better understand the above technical solutions of the present invention, a further detailed description will be given below in conjunction with the drawings and embodiments.

An embodiment of the component connecting rod with the function of precise sustained release of drug doses of the present invention is shown in Figure 2 and Figure 3, the component connecting rod 16 includes a hollow rod body and a first locking device 13 and a second lock connected at both ends of the rod body The component connecting rod 16 is connected to the connected part 11 through the first locking device 13 and the second locking device 14 . 2 and 3, the first locking device 13 and the second locking device 14 are composed of a U-shaped bayonet and a locking nut, and the U-shaped bayonet of the first locking device 13 is connected with the head of the component connecting rod 16. end together. The first locking device 13 can also be an independent connector separated from the component connecting rod 16, like the second locking device 14 shown in Figure 2 and Figure 3, the tail end of the component connecting rod penetrates into the connection of the locking device into the hole and lock with the jackscrew. The connected part 11 in FIG. 2 may be the pedicle screw shown in FIG. 1 , or another component connecting rod.

In the embodiment of the member connecting rod with the function of precise sustained release of drug dose shown in FIG. There is a pneumatic piston 104 inside; the outer circumference of the pneumatic piston 104 is airtightly matched with the inner wall of the drug-loading chamber 107;

The head end of the member connecting rod 16 is provided with a pneumatic push assembly, which is pneumatically connected to the pneumatic piston 104 and can push the pneumatic piston 104 to move axially;

The tail end of the component connecting rod 16 is provided with a drug solution channel 108 and a drug sustained-release channel 109. The drug sustained-release channel 109 is a group of tiny through holes distributed at the tail end of the component connecting rod 16. 108 are connected to form a liquid medicine release channel;

The end of the drug-loaded chamber 107 is provided with a drug liquid release control component, and the drug-loaded chamber 107 is controllably closed or communicated with the drug liquid channel 108 through the drug liquid release control component.

According to an embodiment of the component connecting rod with the function of precise sustained release of drug doses in the present invention, the air pressure push assembly includes a spherical air bag 101, a normally closed air valve 102 and a first body temperature-memory alloy control 103; the spherical air bag 101 is inflated There is a closed sphere with an inert gas higher than atmospheric pressure, and the air outlet of the spherical airbag 101 is hermetically closed by the normally closed air valve 102; when the temperature sensed by the first body temperature-memory alloy control 103 is higher than the memory temperature, the first body temperature-memory alloy The control 103 pushes open the normally closed air valve 102, releases high-pressure gas to push the pneumatic piston 104 to move axially, and discharges the liquid medicine stored in the medicine loading chamber 107 under the action of air pressure. In the embodiment shown in Fig. 2, the normally closed air valve 102 is made of a spring and a small ball matched with the air outlet of the spherical air bag 101, and the small ball is tightly attached to the air outlet of the spherical air bag 101 under spring pressure, The air holes of the spherical airbag 101 are closed to keep the inert gas higher than the atmospheric pressure in the spherical airbag 101 from leaking.

In the embodiment of the component connecting rod with the function of precise sustained release of drug dose shown in FIG. 2, the drug release control assembly includes a drug liquid valve 105 and a second body temperature-memory alloy control 106; The two ends of the chamber 107 are respectively closed by the pneumatic piston 104 and the liquid medicine valve 105 to form an airtight liquid medicine storage space; when the temperature sensed by the second body temperature-memory alloy control 106 is higher than the memory temperature, the second body temperature-memory alloy control 106 opens the liquid medicine valve 105, so that the medicine-loading chamber 107 communicates with the medicine-liquid passage 108, and the medicine in the medicine-loading chamber 107 enters the medicine-liquid passage 108 under the push of the pneumatic piston 104, and passes through the tail of the member connecting rod 16. Each drug slow-release channel 109 at the end releases.

According to a preferred embodiment of the present invention, the first body temperature-memory alloy control 103 and the second body temperature-memory alloy control 106 are spring parts made of body temperature-shape memory alloy, and the structure of the body temperature-shape memory alloy spring part can be based on elastic force and installation The location requirements are designed according to the working fluid technology, which can be either a coil spring or a leaf spring, and its specific structure is not shown in the drawings. The memory temperature of the body temperature-shape memory alloy spring part corresponds to normal human body body temperature. It is characterized in that the first body temperature-memory alloy control and the second body temperature-memory alloy control are spring parts made of body temperature-shape memory alloy; the memory temperature of the body temperature-shape memory alloy spring part corresponds to that of a normal human body Body temperature; when the temperature of the body temperature-shape memory alloy spring part is lower than the body temperature, for example, when the temperature is lower than 35°C, the shape memory alloy spring part is in the memory shape of the folded state, and the normally closed air valve 102 and The liquid medicine valve 105 is kept in the closed position; when the temperature of the body temperature-shape memory alloy spring is equal to or higher than that of the human body, for example, 35°C-40°C, the body temperature-shape memory alloy spring is in a stretched state The normally closed gas valve 102 and the liquid medicine valve 105 are in the open position under the driving force of the body temperature-shape memory alloy spring.

The connecting rod of the component with the function of accurate and sustained release of drug doses of the present invention is stored in an environment below 30°C, and the two ends of the drug-loading chamber 107 are respectively closed by a pneumatic piston 104 and a drug solution valve 105 to form a closed drug solution storage space. The loaded medicinal solution is in airtight storage. After being implanted in the body, the component connecting rod can sense the ambient temperature through the first and second body temperature-memory alloy controls 103 and 106. When the temperature approaches or reaches normal body temperature, the first body temperature-memory alloy control 103 opens the normally closed air valve 102 , open the spherical airbag 101. The inert gas above the atmospheric pressure filled in the spherical airbag 101 generates a pneumatic driving force on the air pressure side of the pneumatic piston 104 to make the pneumatic piston 104 move at a certain speed in the drug-carrying chamber 107 . At the same time, the second body temperature-memory alloy control 106 opens the liquid medicine valve 105, communicates with the medicine-loading chamber 107 and the medicine-liquid passage 108, pushes the medicine liquid stored in the medicine-loading chamber 107 into the medicine-liquid passage 108, and finally connects A group of drug slow-release channels 109 at the end of the rod body of the rod 16, beyond the connecting rod 16 of the overflow member, are slowly and evenly released into the surrounding local tissues, realizing the precise slow-release function of the drug, which can be maintained for a certain period of time after the implantation operation The effective concentration of the drug can help the postoperative recovery of the lesion.

Fig. 4 is an embodiment of the spinal internal fixation system using the component connecting rod of the present invention, in which only the component connecting rod 16 and the connected part 11, the connecting rod 12, and the component connecting rod 16 of the present invention with the function of precise and slow release of drug dosage are shown in the figure. A schematic diagram of the connection relationship between a locking device 13 and a second locking device 14. In this embodiment, the connected part 11 is a pedicle screw with drug sustained release function, and at the tail end of each pedicle screw , also includes a group of sustained drug release holes 109; the component connecting rods 16 of the present invention are between the connecting rods 12, and are used to replace the transverse connecting rods 15 in the existing spinal internal fixation system shown in FIG. 1 .

Those of ordinary skill in the technical field should recognize that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not used as limitations to the present invention. All changes and modifications will fall within the protection scope of the claims of the present invention.

Claims (5)

1. A component connecting rod with the function of precise sustained release of drug doses, comprising a hollow rod body and a first locking device and a second locking device connected to both ends of the rod body, the component connecting rod passes through the first locking device and a second locking device connected to the connected piece, characterized in that: The middle section of the rod body is provided with a drug-loading chamber with a cylindrical cavity structure, and a pneumatic piston is arranged inside the drug-loading chamber, and the outer periphery of the pneumatic piston is airtightly matched with the inner wall of the drug-loading chamber; The head end of the rod body is provided with a pneumatic push assembly, and the air push assembly is pneumatically connected to the pneumatic piston, which can push the pneumatic piston to move in the axial direction; The tail end of the rod body is provided with a liquid medicine channel and a drug sustained-release channel, and the drug sustained-release channel is a group of fine through holes distributed at the tail end of the rod body and connected with the liquid medicine channel. The channels are connected to form a liquid medicine release channel; The end of the drug-loaded chamber is provided with a drug solution release control component, and the drug-loaded room is controllably closed or communicated with the drug solution channel through the drug solution release control component. 2. The member connecting rod with the function of accurate and sustained release of drug dose according to claim 1, characterized in that the said air pressure pushing assembly comprises a spherical air bag, a normally closed air valve and a first body temperature-memory alloy control; said spherical The airbag is a closed sphere filled with an inert gas higher than atmospheric pressure, and the air outlet of the spherical airbag is airtightly closed by a normally closed air valve; when the temperature sensed by the first body temperature-memory alloy control is higher than the memory temperature, the first body temperature- The memory alloy control opens the normally closed air valve, releases high-pressure gas to push the pneumatic piston to move axially, and discharges the liquid medicine stored in the medicine-loading chamber under the action of air pressure. 3. The component connecting rod with the function of accurate and sustained release of drug dose according to claim 1, characterized in that the drug release control assembly includes a drug liquid valve and a second body temperature-memory alloy control; the drug-carrying chamber The two ends of the body are respectively closed by a pneumatic piston and a liquid medicine valve to form an airtight liquid medicine storage space; when the temperature sensed by the second body temperature-memory alloy control is higher than the memory temperature, the second body temperature-memory alloy control opens the said The drug solution valve connects the drug-loading chamber with the drug solution channel, and the drug solution in the drug-loaded room enters the drug solution channel under the push of the pneumatic piston, and is slowly released through each drug distributed at the end of the rod body. channel release. 4. The component connecting rod with the function of precise slow release of drug dosage according to claim 2, characterized in that said first body temperature-memory alloy control is a spring member made of body temperature-shape memory alloy; said body temperature-memory alloy The memory temperature of the shape memory alloy spring part corresponds to the normal body temperature; when the body temperature-the temperature of the shape memory alloy spring part is lower than the body temperature, the shape memory alloy spring part is in the memory shape of the folded state, and the normal The air-closing valve remains in the closed position; when the temperature of the body temperature-shape memory alloy spring part is equal to or higher than the temperature of human body body temperature, the body temperature-shape memory alloy spring part is in the memory shape of the stretched state, and the normally closed gas The valve is in the open position under the pushing force of the body temperature-shape memory alloy spring. 5. The component connecting rod with the function of accurate and slow release of drug dose according to claim 3, characterized in that the second body temperature-memory alloy control is a spring member made of body temperature-shape memory alloy; The memory temperature of the shape memory alloy spring part corresponds to normal human body body temperature; when the body temperature-the temperature of the shape memory alloy spring part is lower than the body temperature, the shape memory alloy spring part is in the memory shape of the folded state, and the medicine The liquid valve remains in the closed position; when the temperature of the body temperature-shape memory alloy spring is equal to or higher than the temperature of the human body, the body temperature-shape memory alloy spring is in the memory shape of the stretched state, and the medicinal liquid The valve is in the open position under the pushing force of the body temperature-shape memory alloy spring.