Osteoporosis is a common and prevalent disease in an aging society and has been recognized as a serious social public health problem. The prevalence of osteoporosis has jumped to the 7th place among various common diseases in the world. With the aging of the population, the risk of osteoporotic fractures in various parts of the body continues to increase as the quality and quantity of bones decline in the elderly. In China, the incidence of osteoporosis in the elderly is 60.72% in men and 90.84% in women. Slight external forces can cause fractures in elderly patients with osteoporosis, with the highest incidence of compression fractures in the spine, which is twice as high as hip fractures.
More than 30% of fractures in the elderly are related to osteoporosis, and the high morbidity and mortality rates of fragility fractures and the high cost of treatment impose a heavy economic burden on families and society. Among vertebral fractures, thoracolumbar fractures are the most common, and patients with vertebral fractures have a higher disability and mortality rate than the general population. This paper makes a brief statement on the current status of treatment for osteoporotic thoracolumbar compression fractures.
1.Non-operative treatment Non-operative treatment mainly focuses on bed rest, including bed rest, pillow repositioning, wearing support, medication for pain relief and functional exercise. The advantage is that it is less disturbing to the body and safer. However, long-term bed rest can accelerate bone loss and cause muscle atrophy, both of which in turn can intensify pain. This forms a vicious circle of osteoporosis-fracture-bedrest-aggravated osteoporosis, in addition to a series of fatal complications such as crushing pneumonia, decubitus ulcers, deep vein thrombosis of the lower extremities, etc. Moreover, the recovery of vertebral height is not ideal and may aggravate spinal deformity. Therefore, attention should be paid to the combination of bed rest and functional exercise, but the time of bed rest and the degree of functional exercise should be grasped to prevent a series of complications caused by bed rest, and to avoid new injuries caused by premature and excessive functional exercise.
Most simple vertebral compression fractures have pain relief after non-operative treatment, but more than 1/3 of patients still have persistent pain. If allowed to progress, a significant portion of the vertebral body will collapse further, resulting in a kyphotic deformity that develops into chronic pain. Severe loss of height of the anterior edge of injured vertebrae in the elderly can result in severe kyphosis deformity after fracture healing, causing changes in the mechanical distribution of the spine and aggravating degeneration, leading to low back pain and affecting daily life. Therefore, it is commonly used for stable fractures with simple vertebral compression fractures, with compression height less than 40% of the vertebral body height, and posterior convexity angle less than 20°, not accompanied by spinal cord injury, or unstable fractures in which the patient is in poor general condition, advanced age, and cannot tolerate surgical treatment.
1.1 Analgesic treatment: Moderate pain control is essential. Narcotic analgesics provide good pain relief, but need to be tightly managed in terms of duration and frequency to avoid addiction. Moreover, they are prone to adverse effects such as weakness, cognitive impairment, nausea, and constipation in the elderly. In addition, pain in patients with vertebral compression fractures may be associated with intraperiosteal inflammation and inflammation of soft tissue changes, which can lead to a vicious cycle of pain and muscle spasm, and narcotic analgesics are not effective in relieving such pain, but require the use of non-steroidal drugs. Such drugs should be applied with attention to the adverse effects on the kidneys and stomach. The application of cyclooxygenase inhibitors can alleviate some of these adverse reactions.
1.2 Anti-osteoporosis treatment: osteoporosis is an intrinsic factor leading to osteoporotic thoracolumbar compression fractures in the elderly. The patient’s organism is in the process of aging, the stressfulness of bone is reduced, bone volume is decreased, and the organism is in long-term negative nitrogen balance, resulting in impaired calcium absorption and active osteoclast function, which makes it easier to cause another fracture in such patients. Non-surgical treatment with prolonged bed rest and braking leads to further bone loss, which can lead to re-fracture and muscle atrophy. Therefore, further evaluation of osteoporosis along with treatment of fractures and early treatment of patients with anti-osteoporotic drugs is necessary to reduce the risk of re-fracture.
The drugs currently used for the treatment of osteoporosis are divided into the following three categories: anti-bone resorption drugs; bone formation-promoting drugs; and bone mineralization drugs. In terms of specific medications, they should be considered on an individual basis. In addition to appropriate calcium supplementation and active vitamin D-based nutritional drugs, anti-bone resorption or bone-formation-promoting preparations can be taken, with the former more commonly used. Recently, Griffith et al. found that as bone mass decreased in osteoporotic patients, bone blood perfusion function also decreased significantly, while bone marrow fat content increased significantly, suggesting that reduced bone blood perfusion may also be an important factor causing bone reconstruction imbalance leading to osteoporosis. More and more clinical data suggest that statins used to lower blood lipids and anti-atherosclerosis have osteoprotective anti-osteoporosis effects.
1.3 Chinese medicine treatment: osteoporosis belongs to the category of back pain and deficiency labor in Chinese medicine. The kidney collects essence, essence produces marrow, and marrow produces bone. Traditional medicine believes that the pathogenesis of osteoporosis is closely related to the kidney, and that “the kidney is the master of bone and marrow” and “the kidney is the master of reproduction”, and this pathogenesis of kidney deficiency has been recognized by most physicians. At present, Western medical treatment mostly uses calcium, active vitamin D, calcitonin and fluoride, which have certain efficacy, but have large side effects. Clinical observations and experimental studies have confirmed that Chinese medicine is effective in the treatment of osteoporosis, with comprehensive effects and few side effects.
2.Vertebroplasty
2.1 Percutaneous vertebroplastyGalibert et al. first used this technique for vertebral hemangioma, and then gradually developed into a treatment for geriatric thoracolumbar fractures. In recent years, vertebroplasty and kyphoplasty have become the treatment of choice for pain associated with osteoporotic vertebral fractures, especially for those patients for whom conservative treatment is ineffective and who have difficulty tolerating open surgery.
Percutaneous vertebroplasty uses percutaneous puncture to inject artificial bone cement into the vertebral body through the pedicle to enhance the strength and stability of the vertebral body, prevent collapse, and relieve low back pain; the mechanism of pain relief by PVP is not yet clear, but the obvious pain relief effect and rapid functional recovery have been widely recognized, and numerous clinical trials have shown that the use of this technique can relieve pain, increase vertebral stability, and improve the patient’s early mobility. A large number of clinical trials have shown that the use of this technique can relieve pain, increase stability of the vertebral body, facilitate early movement of patients and improve quality of life.
However, PVP itself has no repositioning effect and can only achieve “deformity fixation”, which is a major regret of PVP surgery. The pain relief mechanism may be related to the following factors: after the bone cement is injected, the nociceptive nerve endings of the vertebral body are necrosed due to the mechanical, chemical and thermal effects of the cement, which enhances the strength of the vertebral body and reduces pain.
Percutaneous vertebroplasty can cause some complications when injecting bone cement, such as heat reaction during polygraphy and leakage into the spinal canal causing damage to the spinal cord and nerve roots, shock due to a sudden drop in blood pressure, and even life-threatening complications such as pulmonary embolism. The efficacy of vertebroplasty is still controversial. Numerous non-randomized controlled trials have concluded that vertebroplasty is a safe, simple and effective method.
2.2 Percutaneous vertebroplasty
This method uses a balloon-expandable technique to compress the trabeculae within the vertebral body, forming a relatively dense bone wall, closing the channels for cement leakage along the fracture fracture and veins, creating a cavity within the vertebral body, and allowing the cement to be injected into the vertebral body at high viscosity and low pressure;
(2) Reduction of the leakage rate of bone cement and its complications.
Minimally invasive balloon-expandable vertebral body kyphoplasty, developed on the basis of vertebroplasty, can not only restore the height of compressed vertebral body and correct the vertebral body kyphosis, but also play the role of pain relief and reduce the incidence of cement leakage, and has the advantages of minimally invasive, rapid pain relief and early weight-bearing, so it is valued and widely carried out in Europe and the United States, with satisfactory clinical reports. However, since the patients are all elderly with osteoporosis, the balloon expansion squeezes the osteoporotic bone, so the balloon repositioning force is limited, and simple balloon repositioning cannot achieve the maximum vertebral height recovery.
Excessive balloon expansion spreading can lead to endplate fractures. For a severely compressed vertebral body, accurate puncture is very difficult, let alone placing the balloon in the proper position, and improper placement is bound to affect the repositioning effect and even cause new fractures during expansion. At the same time, it is expensive, complicated and cumbersome to operate, which makes its application somewhat limited.
2.3. Sky Expandable Vertebroplasty System
The Sky Expandable Vertebroplasty System has the characteristics of PKP and partially overcomes the shortcomings of balloon kyphoplasty.The Sky Expandable Vertebroplasty System uses a polymer material to perform vertebroplasty on a compression fracture through a minimally invasive surgical approach.The original form of the Sky Expandable Vertebroplasty System is a 418 mm diameter column, which is expanded by rotating its handle. After the original height of the vertebral body has been restored, the former is removed and cement is injected into the cavity to maintain the height of the vertebral body. Compared to vertebroplasty and balloon kyphoplasty, the Sky Expandable Vertebroplasty System has the following advantages.
(1) It is made of a polymer material, which is hollow and uses its own expansion and retraction to create a space, rather than using a balloon expansion method, so it will not rupture and affect the operation;
(2) Controlled directional expansion is adopted, and the expansion in the coronal plane with the working channel as the center does not produce pressure on the lateral wall of the vertebral body, thus minimizing the occurrence of nerve and blood vessel damage or compression due to cement leakage.
3.Open surgery treatment
There is no clear definition of the surgical indication for geriatric thoracolumbar fractures. Vertebroplasty is a relative contraindication to surgery because it cannot effectively increase the volume of the spinal canal, and spinal nerve compression is a relative contraindication to surgery; the application is limited for cases in which the vertebral body is more than 3/4 highly compressed, the fracture involves the posterior wall of the vertebral body, and the fracture block compresses the structures in the spinal canal, especially when accompanied by spinal nerve compression. With advances in anesthesia and other related technologies, the safety of surgery in elderly patients has gradually improved, and open posterior decompression internal fixation is now an effective complementary method for the treatment of osteoporotic thoracolumbar fractures with spinal nerve injury.
Delayed spinal nerve injury and secondary spinal stenosis can be prevented by removing the bone mass in the spinal canal, and early postoperative activity can be achieved, which helps to reduce bone loss and prevent the progression of osteoporosis. Therefore, surgical treatment is advocated for patients who are eligible. The indications for surgical reduction and internal fixation of severe osteoporotic fractures of the vertebral body are clearly defined as those with nerve injury or progressive impairment of nerve function, severe intractable pain, obvious deformity, etc. Poor systemic condition that cannot tolerate surgery and severe osteoporosis are relative contraindications to surgery.
3.1 Posterior resection and decompression internal fixation of the pedicle nail
Posterior resection and decompression has the advantages of simple surgery, small trauma and less bleeding, which can achieve partial or complete repositioning and correction of deformity. Because elderly patients often suffer from osteoporosis, surgery is often difficult to achieve stable fixation. Therefore, the choice of case and surgical method is crucial. This surgical method can restore the physiological curvature and vertebral height of the spine, expand the volume of the spinal canal, and serve the purpose of repositioning, decompression, fixation, and reconstruction of the stability of the spine.
However, the fixation screw is easy to loosen and dislodge when the bone is osteoporotic, so the pedicle screw with thicker diameter, longer length and deeper thread should be used to increase the holding power of the screw. Internal fixation of the pedicle nail is suitable for severe vertebral compression fractures where vertebroplasty cannot be performed, and has the advantages of safety, reliability and good pain relief. However, posterior surgery can further damage the posterior column of the spine, and eventually the anterior, middle and posterior columns of the spine will be damaged. Due to the lack of anterior support, distant spinal correction and vertebral height are easily lost, and complications such as broken rods and kyphosis may occur, and the incidence of low back pain is high.
3.2 Posterior resection and decompression internal fixation of the pedicle nail with cement plasty of the injured spine
This procedure can restore the height and strength of the fractured vertebrae immediately by cementing the injured vertebrae. Ex vivo tests have shown that the compression and fatigue resistance of the post-infusion vertebral body is better than that of the pre-infusion vertebral body. By immediately reconstructing the anterior spinal column, the stress on the posterior internal fixation system is reduced and the incidence of internal fixation failure is reduced.
Compared to injured intravertebral implantoplasty, this procedure is less bleeding, does not have the disadvantages of postoperative pain and infection at the extraction site, and has significant pain relief. However, as with vertebroplasty, it is equally likely to result in serious consequences such as nerve root pain, spinal cord injury, and pulmonary embolism due to bone cement leakage and thermal injury during curing. Moreover, the histocompatibility of bone cement and the ability to induce osteogenesis are not as good as autologous bone tissue, and eventually cannot be replaced by autologous bone tissue.
3.3 Posterior short-segment transforaminal internal fixation with wounded spine osteoplasty
In 1982, Daniaux first reported the injection of autologous bone paste into the vertebral body via the pedicle, and this method has been gradually promoted since then. Bone grafting provides anterior column support for the spine and prevents stresses from concentrating on the fixation, thus reducing the incidence of internal fixation failure and spinal cord compression in delayed kyphosis, and it has less impact on spinal motion than other postero-lateral bone grafting methods.
(1) The injured vertebral arch must be intact bilaterally as the graft access;
(2) In the process of bone grafting, there is a risk of arch root fracture and injury to the adjacent nerve roots;
(3) If the amount of bone graft is too much or improperly pried, there is a risk of damaging the large blood vessels in front of the vertebral body. If the amount of bone graft is too small, it will affect the bone healing of the vertebral body.
3.4 Expansion pedicle screw placement for internal fixation of osteoporotic thoracolumbar fractures in the elderly
Osteoporosis is an important cause of decreased pedicle screw fixation, screw loosening, and fusion failure. Since the pedicle screw is not subjected to all the forces in the body in the direction of its long axis, but also to the transverse flexion moment and rotational stress, screw loosening and dislodgement are the result of the combined effect of these three forces.
According to the principle of mechanical expansion, the stability of the expanded pedicle screw is improved by the following two ways: by using mechanical expansion, the anterior part of the pedicle screw expands and the caudal part is relatively small, which increases the angular angle of the contact surface between the internal plant and the vertebral body and improves the holding force of the screw, so that the screw is stuck in the bony canal of the pedicle and is difficult to pull out; the anterior part of the pedicle screw expands, so that the bone trabeculae around the nail path occur micro The expansion of the anterior portion of the pedicle screw increases the volume of bone density around the nail canal and increases the stability of the expanded pedicle screw by compressing the trabecular space in the cancellous bone between the threads and by increasing the volume of bone density around the nail canal and tightening the joint between the bone and the screw.
In addition, the expanded pedicle screws produce two open “claw” fins after expansion, which are embedded in the vertebral body bone, thus making them have certain anti-rotational properties, and their anti-rotational force is significantly higher than that of ordinary pedicle screws, and the threads of the near-neck part of the expanded pedicle screws gradually become shallower and disappear gradually in the neck part, which is thicker than the other parts. This increases the resistance to fracture and bending of the screw neck and makes it less likely to break or bend the nail. As the expanded pedicle screw in the body over time, there will be bone trabeculae into the screw longitudinal fissure, there is bone generation, forming a “nail in the bone, nail in the bone” phenomenon, so that the screw fixation more firmly.
3.5 Posterior shortening osteotomy internal fixation for osteoporotic thoracolumbar fractures
In order to reduce the formation of pseudarthrosis in the fused segment, a pedicle hook or transverse process hook is added to the segment with the pedicle screw to strengthen its grip, which aims to improve the solidity of internal fixation and provide a good environment for fusion.
Osteoporotic thoracolumbar fractures should avoid the use of hooks or screws alone, and it is generally believed that the vertebral plate hooks have greater superiority than the pedicle nails, because osteoporosis reduces the strength of the cortical and subcortical bones of the spinal roots, and the simple application of pedicle screws can easily cause screw loosening. The chance of internal fixation loosening can also be reduced by increasing the number of fixation segments by 1-2 segments above and below the fractured vertebral body or 2 segments above and 1 segment below and using a vertebral plate hook.
In addition, when correcting the posterior convexity, excessive corrective force should be avoided to avoid loosening of internal fixation or other complications, and complete correction should not be pursued excessively during surgery.
3.6 Anterior decompression Anterior decompression, although more direct and complete, can effectively restore the volume of the spinal canal, provide space for the recovery of spinal cord function, correct kyphosis and obtain a more stable spinal fusion, and
This improves clinical outcomes. However, anterior decompression is associated with more damage and more comorbidities. The hollow screw has a deep thread cut, which has a very strong grip on the cancellous bone and significantly reduces the phenomenon of “cutting”; the screw is hollow and can be filled with autologous bone, which can be connected to the outside world through the opening at the end of the screw and the space between the threads, so that the bone inside and outside the screw can be fused together, making the screw and the bone more closely combined, thus realizing the internal fusion of the osteoporotic vertebral body. internal fixation of osteoporotic vertebrae.
Geriatric thoracolumbar compression fracture is one of the major complications of osteoporosis, which seriously affects the quality of life of patients and has a high rate of disability and death. The treatment of geriatric thoracolumbar compression fractures focuses on prevention, and it is especially important to relieve the painful symptoms caused by fractures and restore daily life in a timely and effective manner. Traditional non-surgical treatments such as bed rest and braces can accelerate bone loss and cause muscle atrophy, which in turn aggravate pain and form a vicious circle.
While surgery is faster, more traumatic, and should be used with caution for those with severe osteoporosis, all of which cannot fully meet the needs of patients. Vertebroplasty is a minimally invasive treatment technique that is simple, safe, and economical, and represents a new direction in the treatment of osteoporotic vertebral compression fractures. However, there are complications such as leakage of filling material, nerve injury, and pulmonary embolism. Recently, the application of a new Vessel-X mesh pocket-shaped bone expander for vertebral strengthening is expected to further reduce the leakage of bone cement.
However, the current calcium phosphate bone cement still fails to take the place of PMMA. The direction of future research lies in finding a composite osteogenic factor, biocompatible, biodegradable, injectable and with good biomechanical properties. The future research direction is to find a filling material with good biocompatible, biodegradable, injectable and good biomechanical properties. In view of the difficulties in the treatment of elderly patients with osteoporotic fractures due to their advanced age, coexisting conditions and high incidence of re-fracture, a proper status assessment of osteoporotic fractures in the elderly should be carried out and the treatment method should be selected rationally. Meanwhile, multidisciplinary comprehensive rehabilitation exercises are crucial for the prognosis and rehabilitation of fractures.