Osteoporosis is a systemic bone disease characterized by reduced bone mass, destruction of bone microarchitecture, increased bone fragility, and susceptibility to fracture (World Health Organization, WHO, 1994). The National Institutes of Health (NIH, 2001) proposed that osteoporosis is a disease of the skeletal system characterized by decreased bone strength and increased risk of fracture, with bone strength including bone mineral density and bone mass.
Osteoporosis can be divided into primary osteoporosis and secondary osteoporosis. Osteoporotic fractures (fragility fractures) are pathological fractures that can occur after osteoporosis due to decreased bone density and bone mass resulting in decreased bone strength, which can occur with minor violence or even during daily activities, and are the most serious consequence of osteoporosis. Common fracture sites are the spine, hip, distal radius and proximal humerus.
Characteristics of osteoporotic fractures and difficulties in treatment.
①After a patient with osteoporosis develops a fracture and becomes bedridden, rapid bone loss will occur, which can aggravate osteoporosis;
②The fracture site has low bone mass and poor bone quality, mostly comminuted fractures, which are difficult to reset and not easy to achieve satisfactory results;
③The stability of internal fixation treatment is poor, the internal fixation and implant are easy to loosen and dislodge, and the bone graft is easy to resorb;
④The fracture healing process is slow, the recovery time is long, and the fracture is prone to delayed healing or even non-healing;
⑤ The risk of re-fracture in other parts of the body is significantly increased;
(6) It is common in the elderly, often accompanied by diseases of other organs or systems, poor general condition, prone to complications during treatment, increasing the complexity and risk of treatment;
(7) The rate of disability and death is high, which seriously threatens the physical and mental health, quality of life and life expectancy of the elderly; therefore, the treatment of osteoporotic fractures is different from general traumatic fractures, and it is necessary to pay attention to the treatment of the fracture itself as well as to actively treat osteoporosis.
Osteoporotic fractures are more common in women and more frequent in people over 60 years of age. Most of them are caused by minor trauma (injury caused by a fall on a flat surface or at the height of the body’s center of gravity) or no obvious history of trauma, and can occur even during daily activities.
The clinical features include general manifestations of fracture; specific manifestations of fracture; X-ray examination can determine the site, type, displacement direction and degree of fracture, which is of great value for fracture diagnosis and treatment. MRI is important for detecting occult fractures and distinguishing fresh from old fractures. Bone densitometry is feasible in patients with a proposed diagnosis of osteoporotic fracture. Dual-energy x-ray absorptiometry (DXA) is currently an internationally accepted method of bone density examination. According to the WHO recommended diagnostic criteria, a DXA BMD value less than 1 standard deviation below the peak bone mass of a healthy adult of the same sex and race is considered normal (T value ≥ -1.0 SD); a decrease of 1-2.5 standard deviations is considered low bone mass (reduced bone mass, -2.5 SD).
Displacement, fixation, functional exercise and anti-osteoporosis treatment are the basic principles of treatment for osteoporotic fractures, and the ideal treatment is an organic combination of all four. The fracture should be repositioned without aggravating the local blood flow obstruction as much as possible, the fracture should be fixed firmly without obstructing the limb movement as much as possible, and the functional exercise should be carried out at an early stage so that the fracture healing and functional recovery can reach a more desirable result. At the same time, anti-osteoporosis drugs are used reasonably to avoid aggravation of osteoporosis or the occurrence of re-fracture. Because osteoporotic fractures are mostly seen in the elderly, the principle of simple, safe and effective methods of repair and fixation should be used to restore the quality of life before the injury as soon as possible, and methods with less trauma and less impact on joint function should be chosen as far as possible.
For those who really need surgery, we should take into account the characteristics of osteoporotic fracture such as poor bone quality and slow healing, which are different from general traumatic fracture, and take the following measures as appropriate.
① Use special internal fixation devices, such as locking compression plates, screws with thick threads, expanded intramedullary nails, and instruments with special coating materials, etc;
② Use devices with less stress masking to reduce further bone loss;
③Adopt special internal fixation techniques, such as screw fixation through bilateral bone cortex, to increase the holding force;
(④) Adopt internal fixation strengthening techniques, such as using bone cement, expanders and biomaterials around the screws to strengthen them;
⑤ For severe bone defects, autologous or allogeneic bone grafts and biomaterials (bone cement, calcium sulfate, etc.) can be considered for filling;
(6) Depending on the firmness of the fracture, external fixation should be used as appropriate. External fixation should be reliable and of sufficient duration to minimize fixation of the joints adjacent to the fracture.
The rehabilitation of patients with osteoporotic fractures should follow the general rule of postoperative rehabilitation of fractures, but also take into account the characteristics of poor bone quality, poor internal fixation and slow fracture healing in this group of patients. Early active and passive muscle exercises, early movement of unfixed joints, and minimizing the time spent in bed are emphasized.
Osteoporotic fractures are commonly found in the spine and hip. The spine is the most common site of osteoporotic fractures, of which about 85% have painful symptoms and the remaining 15% can be asymptomatic. Osteoporotic fractures of the thoracolumbar segment of the spine account for approximately 90% of all spine fractures. Osteoporotic fractures of the spine mainly include vertebral compression fractures and vertebral burst fractures, which are often mildly traumatized or have no obvious history of trauma and are easily missed or misdiagnosed as lumbar back strain.
The diagnosis mainly relies on the patient’s age, medical history and imaging examination, among which post-traumatic thoracic back pain, height reduction, scoliosis or kyphosis, X-ray plain film showing sparse bone trabeculae, thinning of bone cortex, wedge-shaped change of vertebral body and biconcave deformation are the main basis for diagnosis. Bone densitometry, usually by DXA, can determine the degree of osteoporosis, CT scans can determine the type of fracture, the degree of vertebral destruction, and intracanal compression, and MRI examinations can determine whether the fracture is fresh and show the condition of nerve compression.
Vertebral burst fractures without neurological compression can be treated non-operatively with bed rest for 2-3 weeks followed by external fixation in a brace for 3 months. Vertebral burst fractures with neurologic compression symptoms can be treated surgically with nerve decompression, fracture repositioning, internal fixation and fusion. Non-surgical or surgical treatment of vertebral compression fractures should be selected on a case-by-case basis. If the degree of vertebral compression is small (less than 1/3 height loss) and the pain is not severe, non-operative treatment can be adopted. For those with significant vertebral compression (height loss greater than 1/3), no damage to the posterior wall of the vertebral body, or a multi-segment fracture with significant pain and no significant effect by conservative treatment, minimally invasive surgical treatment can be considered. Percutaneous vertebroplasty and kyphoplasty are currently recommended minimally invasive surgical treatment measures to reduce pain, stabilize the spine, restore the physiological curvature of the spine, and achieve early movement. Percutaneous vertebroplasty and kyphoplasty should be performed under close X-ray surveillance, and the surgeon must be formally trained and standardized in surgical techniques to avoid major complications such as bone cement leakage. For multiple vertebral compression fractures, the treatment segment needs to be selected according to the clinical situation.
Osteoporotic fractures of the hip mainly include femoral neck fractures and intertrochanteric fractures, which are characterized by high rates of nonunion, femoral head necrosis, deformation and disability, slow recovery, and high morbidity and mortality.
Non-surgical or surgical treatment is possible depending on the patient’s specific situation. If the fracture is not significantly displaced or is an embedded fracture, or if the patient’s general condition is too poor to tolerate surgery, non-operative treatment can be used. Non-operative treatment includes bed rest, traction (bone traction or skin traction), brace immobilization, infection prevention, nutritional support, and other therapeutic measures. During the non-operative treatment period, close observation of changes in the condition, timely adjustment of limb position and traction weight, and comprehensive measures to prevent and treat complications such as respiratory and urinary system infections and decubitus ulcers should be taken. Surgical treatment includes external fixation frame, internal fixation, artificial joint replacement (artificial femoral head replacement, artificial total hip replacement), etc.
For femoral neck fractures, Garden I and II fractures are mostly fixed with percutaneous multiple hollow compression screws, while Garden III and IV fractures have a low healing rate and a high rate of femoral head necrosis, and the effect of internal fixation is not exact. As for whether to choose artificial femoral head replacement or artificial total hip replacement, it depends on the patient’s age, general condition, life expectancy and whether there is damage to the acetabulum. For elderly patients with poor general condition, short life expectancy and basically intact acetabulum, artificial femoral head replacement can be considered, which can shorten the operation time and reduce bleeding, and elderly patients have less postoperative activities and can basically meet the requirements of daily life, otherwise, artificial total hip replacement is feasible.
For intertrochanteric fracture, internal fixation can be performed by incision and reduction. Internal fixation includes intramedullary fixation and extramedullary fixation, and the intramedullary fixation system includes Gamma nail, proximal femoral intramedullary nail (PFN).
Intramedullary fixation system includes Gamma nail, proximal femoral intramedullary nail (PFN), femoral reconstruction nail, etc. Extramedullary fixation system includes power hip screw (DHS), power condylar screw (DCS), locking compression plate (LCP), hip anatomical plate, etc. Intramedullary or extramedullary fixation can be selected according to the patient’s specific situation and the operator’s experience. For patients with poor bone quality, intramedullary fixation is more in line with biomechanical requirements. If the patient has multiple injuries or is in poor general condition and cannot tolerate larger surgery, closed repositioning can be performed under local anesthesia with external fixation bracket fixation, and the patient can perform functional exercises early after fixation.
Artificial femoral head replacement or total hip arthroplasty is not recommended as the first choice of treatment for intertrochanteric fractures. For intertrochanteric fractures with old fractures or concomitant hip disease, artificial femoral head replacement or artificial total hip arthroplasty can be considered.
Along with surgical treatment of osteoporotic fractures, special emphasis is placed on the aggressive treatment of osteoporosis.
Basic osteo-nutritional supplements, calcium intake can slow bone loss and improve bone mineralization. When used for the treatment of osteoporosis, it should be used in combination with other medications. Vitamin D deficiency can lead to secondary hyperparathyroidism and increased bone resorption, which can cause or worsen osteoporosis. Adequate intake of vitamin D facilitates the absorption of calcium in the gastrointestinal tract, promotes bone formation, and enhances muscle strength and balance.
Osteoporotic fractures originate from osteoporosis, therefore the use of effective medication for osteoporosis is the necessary basis for the treatment of osteoporotic fractures.
Anti-osteoporosis medication recommendation after fracture
1, the early stage of osteoporotic fracture, due to enhanced bone resorption, bed rest and braking and lead to further bone loss, so it is appropriate to use drugs to inhibit bone resorption. Calcitonin can increase bone density, improve bone quality and enhance the biomechanical properties of bone, which has a significant effect on reducing the incidence of osteoporotic fractures. Early application of calcitonin can both relieve pain and improve or prevent acute bone loss, and can be used as the treatment of choice for patients with high-conversion osteoporosis with low back pain (especially in acute fractures of the vertebral body). No adverse effects have been seen in conventional doses on the repair and reconstruction of osteoporotic fractures.
2, the rational use of calcium, calcium absorption is mainly in the intestinal tract, so calcium supplementation to oral effect.
3.Active vitamin D3 can not only promote bone formation and mineralization, increase bone mass and reduce the risk of re-fracture, but also help to enhance muscle strength, improve neuromuscular coordination and prevent the tendency to fall.
4, Bisphosphonates can improve bone density in the lumbar spine and hip, reduce the risk of fracture and mortality in patients after fracture. However, some studies have shown that bisphosphonates can affect the quality of bone scab reconstruction, so the early application of bisphosphonate preparations in osteoporotic fractures is currently debated.
5. SERMs have good efficacy in improving bone density and reducing the incidence of osteoporotic fractures, but some studies have shown that SERMs can increase the risk of venous thrombosis in the lower extremities of bedridden patients, so they should be used with caution in bedridden patients after fracture. It is contraindicated in patients with a history of venous embolism and a propensity for thrombosis (e.g., prolonged bed rest, sedentary). Self-preventive measures include abstinence from smoking and alcohol, moderate weight control, daily moderate muscle strength exercise, whole-body balance and coordination exercise, appropriate outdoor activities, increased sunlight, various measures to prevent falls, and preventive and correct medication use.