A support rod for femoral head necrosis and a method of using the same

Abstract

The present invention discloses a support rod for femoral head necrosis, characterized in that it comprises a head section rod and a tail section rod, the center of the head section rod is provided with a head section inner hole, the center of the tail section rod is provided with a tail section inner hole, the outer side wall of the tail section rod is provided with a first external thread, the outer side wall of the head section rod is provided with a first spiral groove, the inner side wall of the head section rod is provided with a first radial hole, and the first radial hole connects the first spiral groove with the head section inner hole. The present invention can provide sufficient support strength, and at the same time, in the early stage of implantation, all tissue fluid that causes increased internal pressure in the femoral head can flow out of the bone, and in the later stage of implantation, a certain space can be reserved for the growth of new bone cells, so that the patient can avoid femoral head collapse when walking normally, which is conducive to the growth of bone tissue and close combination with the support rod to increase mechanical properties. In addition, the present invention also discloses a method of use.

Description

Technical Field

[0001] The invention belongs to a femoral head necrosis support rod and a use method thereof. Background Art

[0002] Femoral head necrosis is one of the common and difficult-to-treat chronic diseases in orthopedic clinics. According to incomplete statistics, there are about 30 million patients with femoral head necrosis in the world, and about 4 million in China. In the early stages of the disease, it is often manifested as dull pain around the hip joint, which worsens after activity. Further development can lead to collapse of the femoral head, and ultimately only an artificial joint can be replaced. Clinical intervention in the early and middle stages of femoral head necrosis to delay or prevent femoral head collapse is an important measure to preserve the hip. In the past, the main intervention method for early and middle-stage patients was to drill holes to decompress the femoral head. Although simple decompression can relieve pain symptoms, it may accelerate the collapse of the femoral head due to the lack of mechanical support in the necrotic area.

[0003] There is currently a publicly available support rod for femoral head necrosis (publication number CN207745180U), which is implanted in the femoral head for support and can prevent the femoral head from collapsing. However, the problem of increased internal pressure in the femoral head is easy to occur.

[0004] There is a support rod (publication number CN201500170U) that is inserted into the femoral head. The rod body is a hollow cylindrical shape. The tail of the rod body is screwed together with the rod head. There is a spiral thread on the outer wall of the tail of the rod body. The tail of the rod body is screwed together with the rod head. The top of the rod head has a guide pin hole that is concentric with the tail of the rod body. It has the ability to support the collapsed cartilage shell. Different rod head combinations can be selected according to the length of the femoral head. Only one guide pin hole is set, which has insufficient decompression effect. At the same time, the outer wall of the rod head is smooth, which is not conducive to the growth of new bone tissue and reduces the bonding strength with the support rod. Summary of the invention

[0005] In order to solve one or more of the above-mentioned defects in the prior art, the present invention provides a femoral head necrosis support rod.

[0006] To achieve the above-mentioned purpose, the present invention provides a femoral head necrosis support rod, characterized in that it comprises a head section rod (1) and a tail section rod (2), the head section rod (1) is provided with a head section inner hole (1-1) at the center, the tail section rod (2) is provided with a tail section inner hole (2-1) at the center, the tail section rod (2) has a first external thread (2-2) on the outer wall, the head section rod (1) is provided with a first spiral groove (1-2) on the outer wall, the head section rod (1) is provided with a first radial hole (1-3) on the inner wall, and the first radial hole (1-3) connects the first spiral groove (1-2) with the head section inner hole (1-1). By adopting the above-mentioned scheme, when in use, the head section rod (1) and the tail section rod (2) are implanted into the femoral head at the same time, and the tail section rod is fixed by screwing its first external thread with the femoral head thread to prevent the head section rod from sliding outward. Firstly, since the head section rod (1) and the tail section rod (2) are implanted in the femoral head, a good supporting effect can be achieved on the necrotic area of ​​the femoral head, and collapse of the femoral head can be avoided; secondly, since the first spiral groove (1-2) is provided on the outer wall of the head section rod (1), the first radial hole (1-3) is provided on the inner wall of the head section rod (1), and the first radial hole (1-3) connects the first spiral groove (1-2) with the head section inner hole (1-1), the tissue fluid in the necrotic area of ​​the femoral head is collected in the whole range through the first spiral groove (1-2) and flows into the head section through the first radial hole (1-3). The fluid flows out of the bone from the inner hole (1-1) of the tail section, and then out of the bone from the inner hole (2-1) of the tail section. Therefore, the tissue fluid and necrotic tissue fluid that cause the internal pressure increase in the femoral head can be completely drained out of the bone in the early stage of implantation. Thirdly, since the first spiral groove (1-2) has a high friction stability with the bone and also reserves a certain gap space for the growth of new bone cells, it can induce the formation of new bone, which is beneficial for the growth of bone tissue and the close combination with the support rod to increase the mechanical properties, thereby having a good therapeutic effect and reducing the risk of displacement and loosening of the femoral head necrosis support rod when the patient walks normally.

[0007] Furthermore, a reinforcing lining is provided on the inner wall of the inner hole (1-1) of the head section. When the head section rod (1) is made of the pubic bone or radius of the allogeneic bone, the side wall thickness is small and the strength is limited after the inner hole of the pubic bone or radius is processed, so there is a problem of insufficient support strength. The reinforcing lining is lined in the head section rod (1) and greatly improves the anti-deformation strength of the head section rod (1), which can greatly enhance the supporting effect on the femoral head necrosis area and avoid the collapse of the femoral head. In addition, the use of the lining setting can greatly reduce or directly avoid the problem of severe rejection caused by direct contact between the reinforcing lining and the bone itself.

[0008] As a first preferred embodiment, the reinforcing lining member adopts a rigid spiral sheet (3-1). The rigid spiral sheet (3-1) is screwed into the inner wall of the head section inner hole (1-1) of the head section rod (1) to form a spiral support, which is easy to install. At the same time, the rigid spiral sheet (3-1) is tightened after being screwed in and will not loosen axially, and will not affect the drainage function of the first radial hole (1-3).

[0009] As a second preferred embodiment, the reinforcing lining member adopts a rigid bushing (3-2), the outer wall surface of which is provided with a second spiral groove (3-21), and the rigid bushing (3-2) is provided with a second radial hole (3-22) for connecting the second spiral groove (3-21) with the inner hole of the rigid bushing (3-2). The rigid bushing (3-2) is screwed into the inner wall of the head section inner hole (1-1) of the head section rod (1) to form a circumferential strength support, and the second spiral groove (3-21) and the head section inner hole (1-1) of the head section rod (1) are lined with an interference fit and a rough fit to avoid loosening; at the same time, the tissue fluid drained from the first radial hole (1-3) can be collected through the second spiral groove (3-21) and then flow into the inner hole of the rigid bushing (3-2) from the second radial hole (3-22), and then flow out of the bone through the tail section inner hole (2-1).

[0010] The rigid bushing (3-2) is made of titanium alloy or other known materials that can provide sufficient rigidity and can be implanted into bones.

[0011] Furthermore, the head section rod (1) and the tail section rod (2) are fixed by a threaded structure. The head section rod (1) and the tail section rod (2) are fixed as one body to improve the overall strength and prevent the head section rod (1) and the tail section rod (2) from loosening due to relative axial displacement.

[0012] Preferably, a second internal thread (1-11) is provided on the inner wall of the tail end of the head section inner hole (1-1) of the head section rod (1);

[0013] The head end of the tail section rod (2) comprises an extension tube (2-11) and a step surface (2-12); the outer wall of the extension tube (2-11) is provided with a second external thread (2-111) for cooperating with the second internal thread (1-11); the step surface (2-12) is provided with a plurality of one-way stop teeth (2-121) along the circumferential direction; the tail end surface of the head section rod (1) is provided with a plurality of one-way stop grooves (1-13) for cooperating with the one-way stop teeth (2-121) along the circumferential direction; the rotation direction of the extension tube (2-11) when screwed into the second internal thread (1-11) is opposite to the direction in which the one-way stop groove (1-13) stops the one-way stop teeth (2-121). When the second external thread (2-111) and the second internal thread (1-11) of the extension tube (2-11) are screwed into place, the one-way stopping tooth (2-121) is stopped and clamped by the one-way stopping groove (1-13) to limit the second external thread (2-111) and the second internal thread (1-11) of the extension tube (2-11) from loosening in reverse rotation, and the tail section rod (2) and the head section rod are mutually self-locked and will not loosen axially or rotationally.

[0014] Preferably, the one-way stopping groove (1-13) and the one-way stopping tooth (2-121) are sawtooth-shaped.

[0015] Preferably, the head section rod (1) and the tail section rod (2) are made of allogeneic pubic bone or radius, so that the head section rod (1) and the tail section rod (2) have the same stress and strain mode in the femoral head, which can reduce the stress shielding effect.

[0016] In addition, another object of the present invention is to disclose a method of use, which adopts a femoral head necrosis support rod as described in any one of the above technical solutions, characterized in that it includes the following steps:

[0017] S10, drill a hole in the necrotic part of the femur to obtain a cavity;

[0018] S20. Use a curette to clean the necrotic part of the cavity;

[0019] S30, tapping the outer end of the cavity with a tap to obtain a first internal thread with a length of 25-35 mm;

[0020] S40, inserting the head section rod into the cavity;

[0021] S50, inserting the head end of the tail section rod into the cavity first, and then rotating the tail section rod so that the first external thread and the first internal thread are screwed together and fixed and preventing the head section rod from sliding outward.

[0022] The beneficial effects of the present invention are:

[0023] First, since the head section rod and the tail section rod are implanted in the femoral head, the present invention can provide a good support to the necrotic area of ​​the femoral head and avoid the collapse of the femoral head;

[0024] Secondly, the present invention provides a first spiral groove on the outer wall of the head section rod, and a first radial hole on the inner wall of the head section rod, and the first radial hole connects the first spiral groove with the inner hole of the head section, so that the tissue fluid in the necrotic area of ​​the femoral head is fully collected by the first spiral groove and flows into the inner hole of the head section through the first radial hole, and then flows out of the bone from the inner hole of the tail section. Therefore, the tissue fluid that causes the internal pressure increase in the femoral head and the necrotic tissue fluid can be completely drained out of the bone in the early stage of implantation;

[0025] Third, the present invention has high friction stability with the bone because the first spiral groove and the bone also reserve a certain gap space for the growth of new bone cells, which can induce the formation of new bone, and is conducive to the growth of bone tissue and the close combination with the support rod to increase the mechanical properties, thereby having a good therapeutic effect, and enabling the patient to walk normally, and reduce the risk of displacement and loosening of the femoral head necrosis support rod;

[0026] Fourthly, the present invention greatly improves the anti-deformation strength of the head section rod because the reinforcing lining is lined in the head section rod, which can greatly enhance the support effect on the femoral head necrosis area and avoid the collapse of the femoral head. In addition, the use of the lining setting can greatly reduce or directly avoid the problem of serious rejection caused by direct contact between the reinforcing lining and the bone itself;

[0027] Fifth, the present invention adopts a rigid spiral sheet as the reinforcing lining member. The rigid spiral sheet is screwed into the inner wall of the head section inner hole of the head section rod to form a spiral support, which is easy to install. At the same time, the rigid spiral sheet is tightened after being screwed in and will not loosen axially, and will not affect the drainage function of the first radial hole;

[0028] Sixth, the present invention forms circumferential strength support because the rigid bushing is screwed into the inner wall of the head section inner hole of the head section rod, and the second spiral groove is interference fit with the head section inner hole of the head section rod and is roughly fit to avoid loosening; at the same time, the tissue fluid drained from the first radial hole can be collected by the second spiral groove and then flow into the inner hole of the rigid bushing from the second radial hole, and then flow out of the bone through the inner hole of the tail section;

[0029] Seventh, the present invention fixes the head section rod and the tail section rod by a threaded structure. The head section rod and the tail section rod are fixed as one body to improve the overall strength, and at the same time, prevent the head section rod and the tail section rod from being loosened due to relative axial displacement;

[0030] Seventh, in the present invention, since the rotation direction of the extension tube of the tail section rod when it is screwed into the second internal thread of the head section rod is opposite to the direction in which the one-way stop groove stops the one-way stop tooth, when the second external thread of the extension tube and the second internal thread are screwed into place, the one-way stop tooth is stopped and stuck by the one-way stop groove to limit the second external thread of the extension tube and the second internal thread from loosening in reverse rotation, the tail section rod and the head section rod are mutually self-locked and will not loosen axially or in rotation at the same time;

[0031] Eighth, since the head section rod and the tail section rod of the present invention are made of allogeneic pubic bone or radius, the head section rod and the tail section rod have the same stress and strain pattern in the femoral head, which can reduce the stress shielding effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a cross-sectional view of the head section rod in the first embodiment of the present invention.

[0033] Figure 2 It is a stereoscopic diagram of the head section rod in the first embodiment of the present invention.

[0034] Figure 3 It is a cross-sectional view of the tail section rod in the first embodiment of the present invention.

[0035] Figure 4 It is a three-dimensional diagram of the tail section rod in the first embodiment of the present invention.

[0036] Figure 5 yes Figure 3 Right projection view of .

[0037] Figure 6 This is a usage diagram of a femoral head necrosis support rod in Example 1 of the present invention.

[0038] Figure 7 It is a three-dimensional diagram of the tail section rod in the second embodiment of the present invention.

[0039] Figure 8 It is a split stereoscopic diagram of a femoral head necrosis support rod in Example 2 of the present invention when it is not screwed together.

[0040] Fig. 9 yes Figure 8 Enlarged view of point A in the middle.

[0041] Fig.10 It is a three-dimensional assembly diagram of a femoral head necrosis support rod in Embodiment 2 of the present invention when it is screwed into place.

[0042] Fig.11 yes Fig.10 Enlarged view of point B in the middle.

[0043] Fig.12 It is an assembly cross-sectional view of a femoral head necrosis support rod in Embodiment 2 of the present invention when it is screwed into place.

[0044] Fig.13 It is a split stereoscopic diagram of a femoral head necrosis support rod in Example 3 of the present invention when it is not assembled and connected (when the reinforced lining member adopts a rigid bushing).

[0045] Fig.14 It is an assembly cross-sectional view of a femoral head necrosis support rod in Embodiment 3 of the present invention when it is assembled and screwed into place (when a rigid bushing is used as the reinforced lining member).

[0046] Fig.15 yes Fig.14 Enlarged view of center C.

[0047] Fig.16 It is a split stereoscopic diagram of a femoral head necrosis support rod in Example 4 of the present invention when it is not assembled and connected (when the reinforcing lining member adopts a rigid spiral sheet).

[0048] Fig.17 It is an assembly cross-sectional view of a femoral head necrosis support rod in Embodiment 4 of the present invention when it is assembled and screwed into place (when a rigid spiral sheet is used as the reinforcing lining member). DETAILED DESCRIPTION

[0049] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0050] Example 1: See Figure 1-6 A femoral head necrosis support rod comprises a head section rod 1 and a tail section rod 2. The head section rod 1 is provided with a head section inner hole 1-1 at the center, the tail section rod 2 is provided with a tail section inner hole 2-1 at the center, the tail section rod 2 has a first external thread 2-2 on the outer wall, the head section rod 1 is provided with a first spiral groove 1-2 on the outer wall, the head section rod 1 is provided with a first radial hole 1-3 on the inner wall, and the first radial hole 1-3 connects the first spiral groove 1-2 with the head section inner hole 1-1.

[0051] Preferably, the depth T of the first spiral groove 1-2 is 2-3 mm.

[0052] Preferably, the head section rod 1 and the tail section rod 2 are made of allogeneic pubic bone or radius, so that the head section rod 1 and the tail section rod 2 have the same stress and strain mode in the femoral head, which can reduce the stress shielding effect.

[0053] In addition, further, a straight knife groove 2-3 or a cross knife groove is provided on the tail end surface of the tail section rod 2. The straight knife or the cross knife knob can be used for operation, saving time and effort.

[0054] The preparation method of the femoral head necrosis support rod in this embodiment is as follows:

[0055] First, the material can be selected. The head section rod 1 and the tail section rod 2 can be made of allogeneic pubic bone or radius;

[0056] Cutting: Use a saw to cut the pubic bone or radius to 70-80mm long;

[0057] Rough machining: Use a lathe to process, clamp one end 2-3mm with the chuck, support the other end with an external center, and cut after adjusting the center.

[0058] Finishing: After rough machining, the outer circle and threaded part of the blank are first machined, and finally the inner hole and two end faces are machined.

[0059] The method for using the femoral head necrosis support rod in this embodiment may include the following steps:

[0060] S10, drill a hole in the necrotic part of the femur to obtain a cavity;

[0061] S20. Use a curette to clean the necrotic part of the cavity;

[0062] S30, tapping the outer end of the cavity with a tap to obtain a first internal thread with a length of 25-35 mm;

[0063] S40, inserting the head section rod into the cavity;

[0064] S50, insert the head end of the tail section rod into the cavity first, and then rotate the tail section rod to screw the first external thread and the first internal thread together to fix and prevent the head section rod from sliding out. In this embodiment, the tail section rod abuts against the head section rod.

[0065] When in use, the head section rod 1 and the tail section rod 2 are implanted into the femoral head at the same time, and the tail section rod is fixed by screwing its first external thread with the femoral head thread to prevent the head section rod from sliding out.

[0066] The present invention has the following characteristics and is analyzed as follows:

[0067] First, since the head section rod 1 and the tail section rod 2 are implanted in the femoral head, a good support effect can be achieved for the necrotic area of ​​the femoral head, thereby preventing the collapse of the femoral head;

[0068] Second, since the first spiral groove 1-2 is provided on the outer wall of the head section rod 1, the first radial hole 1-3 is provided on the inner wall of the head section rod 1, and the first radial hole 1-3 connects the first spiral groove 1-2 with the head section inner hole 1-1, the tissue fluid in the necrotic area of ​​the femoral head is collected in the whole range through the first spiral groove 1-2 and flows into the head section inner hole 1-1 through the first radial hole 1-3, and then flows out of the bone from the tail section inner hole 2-1, so that the tissue fluid that causes the increased internal pressure in the femoral head and the necrotic tissue fluid can be completely drained out of the bone in the early stage of implantation;

[0069] Third, since the first spiral groove 1-2 has high friction stability with the bone and also reserves a certain gap space for the growth of new bone cells, it can induce the formation of new bone, which is beneficial for the growth of bone tissue and the close combination with the support rod to increase the mechanical properties, thereby having a good therapeutic effect and reducing the risk of displacement and loosening of the femoral head necrosis support rod when the patient walks normally.

[0070] Embodiment 2: This embodiment is basically the same as Embodiment 1, except that:

[0071] See also Figure 7-12 Furthermore, the head section rod 1 and the tail section rod 2 are fixed by a threaded structure. The head section rod 1 and the tail section rod 2 are fixed as one body to improve the overall strength and prevent the head section rod 1 and the tail section rod 2 from being loosened due to relative axial displacement.

[0072] Preferably, a second internal thread 1-11 is provided on the inner wall of the tail end of the inner hole 1-1 of the head section rod 1;

[0073] The head end of the tail section rod 2 has an extension tube 2-11 and a step surface 2-12, and the outer wall of the extension tube 2-11 is provided with a second external thread 2-111 for cooperating with the second internal thread 1-11; the step surface 2-12 is provided with a plurality of one-way stop teeth 2-121 (evenly distributed along the circumferential direction) along the circumferential direction, and the tail end surface of the head section rod 1 is provided with a plurality of one-way stop grooves 1-13 (evenly distributed along the circumferential direction) for cooperating with the one-way stop teeth 2-121 along the circumferential direction; the rotation direction of the extension tube 2-11 when it is screwed into the second internal thread 1-11 is opposite to the direction in which the one-way stop groove 1-13 stops the one-way stop tooth 2-121. When the second outer thread 2-111 and the second inner thread 1-11 of the extension tube 2-11 are tightened into place, the one-way stopping tooth 2-121 is stopped and clamped by the one-way stopping groove 1-13 to limit the reverse rotation loosening of the second outer thread 2-111 and the second inner thread 1-11 of the extension tube 2-11. The tail section rod 2 and the head section rod are self-locking with each other and will not loosen axially or rotationally at the same time, which can ensure long-term stable and rigid connection of the coaxial rod and prevent mutual loosening at the same time, so that the femoral head necrosis support rod can provide long-term stable and reliable support in the femoral head, and at the same time is beneficial to the bonding strength of new bone growth (because slight loosening will seriously affect the bonding strength of new bone growth).

[0074] Preferably, the one-way stopping groove 1-13 and the one-way stopping tooth 2-121 are serrated.

[0075] The method for using the femoral head necrosis support rod in this embodiment may include the following steps:

[0076] S10, drill a hole in the necrotic part of the femur to obtain a cavity;

[0077] S20. Use a curette to clean the necrotic part of the cavity;

[0078] S30, tapping the outer end of the cavity with a tap to obtain a first internal thread with a length of 25-35 mm;

[0079] S40, inserting the head section rod into the cavity;

[0080] S50. Insert the head end of the tail section rod into the cavity first, and then rotate the tail section rod so that the first external thread and the first internal thread are screwed together and fixed. When the second external thread 2-111 and the second internal thread 1-11 of the extension tube 2-11 are screwed into place, the one-way stopping tooth 2-121 is stopped and clamped by the one-way stopping groove 1-13 to limit the second external thread 2-111 and the second internal thread 1-11 of the extension tube 2-11 from loosening in reverse rotation. The tail section rod 2 and the head section rod are self-locking with each other and will not loosen axially or rotationally, while preventing the head section rod from sliding out.

[0081] Embodiment 3: This embodiment is basically the same as Embodiment 1 or 2, except that:

[0082] See also Figure 13-15 In this embodiment, a reinforcing lining is provided on the inner wall of the inner hole 1-1 of the head section. When the head section rod 1 is made of allogeneic bone pubic bone or radius, the side wall thickness is small and the strength is limited after the inner hole of the allogeneic bone pubic bone or radius is processed, so there is a problem of insufficient supporting strength. The reinforcing lining is lined in the head section rod 1 and greatly improves the anti-deformation strength of the head section rod 1, which can greatly enhance the supporting effect on the necrotic area of ​​the femoral head and avoid the collapse of the femoral head. In addition, the use of the lining setting can greatly reduce or directly avoid the problem of severe rejection caused by direct contact between the reinforcing lining and the bone itself.

[0083] In this embodiment, the reinforcing lining member adopts a rigid bushing 3-2, and a second spiral groove 3-21 is provided on the outer wall of the rigid bushing 3-2, and a second radial hole 3-22 is provided on the rigid bushing 3-2 to connect the second spiral groove 3-21 with the inner hole of the rigid bushing 3-2. The rigid bushing 3-2 is screwed into the inner wall of the head section inner hole 1-1 of the head section rod 1 to form a circumferential strength support, and the second spiral groove 3-21 is lined with the head section inner hole 1-1 of the head section rod 1 to form an interference fit and a rough fit to avoid loosening; at the same time, the tissue fluid drained from the first radial hole 1-3 can be collected by the second spiral groove 3-21 and then flow into the inner hole of the rigid bushing 3-2 from the second radial hole 3-22, and then flow out of the bone through the tail section inner hole 2-1.

[0084] The rigid bushing 3 - 2 is made of titanium alloy or other known materials that can provide sufficient rigidity and can be implanted into bones.

[0085] Preferably, the rigid bushing 2-4 has a thickness of mm, and the second spiral groove 3-21 has a depth of 1 mm, a width of 3-5 mm, and a pitch of 6-7 mm. This can ensure that sufficient liner support strength is provided, and at the same time, tissue fluid can be smoothly collected by the second spiral groove 3-21 and then flow into the inner hole of the rigid bushing 3-2 from the second radial hole 3-22.

[0086] Preferably, the inner hole of the extension tube 2-11 is equal to the inner hole of the rigid bushing 3-2. Each of the second radial holes 3-22 corresponds to each of the first radial holes 1-3 in the axial direction. In this way, when the second external thread 2-111 of the extension tube 2-11 is screwed into the second internal thread 1-11 and locked, it will squeeze the rigid bushing 3-2 to move axially inward and press against the outside, which can prevent the rigid bushing 3-2 from sliding outward, and at the same time, the rigid bushing 3-2 can be positioned and installed, so that the second radial hole 3-22 can be aligned or close to the first radial hole 1-3, which can reduce the length of the drainage path and utilize timely drainage and discharge.

[0087] The method for using the femoral head necrosis support rod in this embodiment may include the following steps:

[0088] S10, drill a hole in the necrotic part of the femur to obtain a cavity;

[0089] S20. Use a curette to clean the necrotic part of the cavity;

[0090] S30, tapping the outer end of the cavity with a tap to obtain a first internal thread with a length of 25-35 mm;

[0091] S40, screw the reinforcing lining (rigid bushing 3-2) into the head section rod and leave a margin (preferably 3-5 mm);

[0092] S50, inserting the head section rod lined with the reinforced lining member (rigid bushing 3-2) into the cavity;

[0093] S60. Insert the head end of the tail section rod into the cavity first, and then rotate the tail section rod to screw the first external thread and the first internal thread together and fix it. When the second external thread 2-111 and the second internal thread 1-11 of the extension tube 2-11 are screwed into place, the one-way stopping tooth 2-121 is stopped and clamped by the one-way stopping groove 1-13 to limit the second external thread 2-111 and the second internal thread 1-11 of the extension tube 2-11 from loosening in reverse rotation. At the same time, the extension tube 2-11 presses against the reinforcing lining (rigid bushing 3-2) and positions it.

[0094] Embodiment 4: This embodiment is basically the same as Embodiment 1, 2 or 3, except that:

[0095] See also Figure 16-17 In this embodiment, a reinforcing lining is provided on the inner wall of the inner hole 1-1 of the head section.

[0096] In this embodiment, the reinforcing lining member is a rigid spiral sheet 3-1. The rigid spiral sheet 3-1 is screwed into the inner wall of the head section inner hole 1-1 of the head section rod 1 to form a spiral support, which is easy to install. At the same time, the rigid spiral sheet 3-1 is clamped after being screwed in and will not loosen axially, and will not affect the drainage function of the first radial hole 1-3.

[0097] The rigid spiral sheet 3 - 1 can be made of titanium alloy or other known materials that can provide sufficient rigidity and can be implanted into bones.

[0098] The inner hole of the rigid spiral sheet 3-1 is equal to the inner hole of the rigid bushing 3-2. Thus, when the second outer thread 2-111 of the extension tube 2-11 is screwed into the second inner thread 1-11 and locked, the rigid spiral sheet 3-1 is squeezed to move axially inward and pressed against the outside, thereby preventing the rigid spiral sheet 3-1 from sliding outward.

[0099] The method for using the femoral head necrosis support rod in this embodiment may include the following steps:

[0100] S10, drill a hole in the necrotic part of the femur to obtain a cavity;

[0101] S20. Use a curette to clean the necrotic part of the cavity;

[0102] S30, tapping the outer end of the cavity with a tap to obtain a first internal thread with a length of 25-35 mm;

[0103] S40, screw the reinforcing lining (rigid spiral sheet 3-1) into the head section rod and leave a margin (preferably 3-5 mm);

[0104] S50, inserting the head section rod lined with the reinforced lining member (rigid spiral sheet 3-1) into the cavity;

[0105] S60. Insert the head end of the tail section rod into the cavity first, and then rotate the tail section rod to screw the first external thread and the first internal thread together and fix it. When the second external thread 2-111 and the second internal thread 1-11 of the extension tube 2-11 are screwed into place, the one-way stopping tooth 2-121 is stopped and clamped by the one-way stopping groove 1-13 to restrict the second external thread 2-111 and the second internal thread 1-11 of the extension tube 2-11 from loosening in reverse rotation. At the same time, the extension tube 2-11 presses against the reinforcing lining (rigid spiral sheet 3-1) and positions it.

[0106] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A support rod for femoral head necrosis, characterized in that: It comprises a head section rod (1) and a tail section rod (2); The center of the head section rod (1) is provided with a head section inner hole (1-1), and the center of the tail section rod (2) is provided with a tail section inner hole (2-1); the outer side wall of the tail section rod (2) is provided with a first external thread (2-2); A first spiral groove (1-2) is provided on the outer side wall of the head section rod (1), a first radial hole (1-3) is provided on the inner side wall of the head section rod (1), and the first radial hole (1-3) enables the first spiral groove (1-2) to communicate with the head section inner hole (1-1); The head section rod (1) and the tail section rod (2) are fixed by a threaded structure; The inner wall of the tail end of the head section inner hole (1-1) of the head section rod (1) is provided with a second internal thread (1-11); the head end of the tail section rod (2) has an extension tube (2-11) and a step surface (2-12); the outer wall of the extension tube (2-11) is provided with a second external thread (2-111) for cooperating with the second internal thread (1-11); the step surface (2-12) is provided with a plurality of one-way stop teeth (2-121) along the circumferential direction; the tail end surface of the head section rod (1) is provided with a plurality of one-way stop grooves (1-13) for cooperating with the one-way stop teeth (2-121) along the circumferential direction; the rotation direction of the extension tube (2-11) when screwed into the second internal thread (1-11) is opposite to the direction in which the one-way stop groove (1-13) stops the one-way stop teeth (2-121); The first spiral groove has a depth of 2-3 mm.

2. A support rod for femoral head necrosis as claimed in claim 1, characterized in that: A reinforcing lining piece is arranged on the inner wall of the head section inner hole (1-1).

3. A support rod for femoral head necrosis as claimed in claim 2, characterized in that: The reinforced lining member adopts a rigid spiral sheet (3-1).

4. A support rod for femoral head necrosis as claimed in claim 2, characterized in that: The reinforced lining member adopts a rigid bushing (3-2), the outer wall surface of which is provided with a second spiral groove (3-21), and the rigid bushing (3-2) is provided with a second radial hole (3-22) for connecting the second spiral groove (3-21) with the inner hole of the rigid bushing (3-2).

5. A support rod for femoral head necrosis as claimed in claim 1, characterized in that: The one-way stopping groove (1-13) and the one-way stopping tooth (2-121) are sawtooth-shaped.

6. A support rod for femoral head necrosis as claimed in claim 1, characterized in that: The head section rod (1) and the tail section rod (2) are made of allogeneic pubic bone or radius.

7. A method of use, using a femoral head necrosis support rod as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: S10, drill a hole in the necrotic part of the femur to obtain a cavity; S20. Use a curette to clean the necrotic part of the cavity; S30, tapping the outer end of the cavity with a tap to obtain a first internal thread with a length of 25-35 mm; S40, inserting the head section rod into the cavity; S50, inserting the head end of the tail section rod into the cavity first, and then rotating the tail section rod so that the first external thread and the first internal thread are screwed together and fixed and preventing the head section rod from sliding outward.

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