Authors: Jianzheng Zhang, Licheng Zhang, Chunbao Li, Wei Chai, Lihai Zhang, Hua Chen, Wei Zhang, Zhiyong Hou, Bin Chen, Tiansheng Sun, Peifu Tang, Yingze Zhang
Categories: Guideline, Elderly, Fractures of the pelvis, Fragility, Osteoporosis
Source: Orthopaedic Surgery
Doi: 10.1111/os.13755
Fragility fractures of the pelvis (FFPs) are osteoporotic pelvic fractures or insufficiency pelvic fractures caused by the low energy injury or stress fracture in daily livings in the elderly more than 60 years, which the incidence is increasing with the aging population in our country. FFPs result in considerable morbidity and mortality and as well as massive financial burden on the already strained health systems throughout the world.
This clinical guideline was initiated by the Trauma Orthopedic Branch of Chinese Orthopedic Association; the External Fixation and Limb Reconstruction Branch of Chinese Orthopedic Association; the National Clinical Research Center for Orthopedics, Sports Medicine & Rehabilitation; Senior Department of Orthopedics of Chinese PLA general hospital; the Third Hospital of Hebei Medical University. The grading of recommendations assessment, development and evaluation (GRADE) approach and the reporting items for practice guidelines in healthcare (RIGHT) checklist were adopted.
22 evidence based recommendations were formulated based on 22 most concerned clinical problems among orthopedic surgeons in China.
Understanding these trends through this guideline will facilitate better clinical care of FFP patients by medical providers and better allocation of resources by policy makers.
Keywords: Elderly, Fractures of the pelvis, Fragility, Osteoporosis
Fragility fractures of the pelvis (FFPs) have taken a lesser role to the more easily diagnosed and more prevalent geriatric hip, vertebral, and upper extremity fractures for years. However, with the worldwide availability and accessibility of CT and population aging, FFP specifically are increasing and becoming recognized as a very important player in the osteoporotic fractures landscape. ^1^ As of 2005 pelvic fragility fractures accounted for 7% of all osteoporotic fractures. By 2025 the overall increase in all osteoporotic fractures is expected to rise by 20%, where pelvic fragility fractures are expected to disproportionately rise by 56% in the United States. ^2^ In a Scandinavian population of individuals 80 years or older, the number and age adjusted incidence of low‐energy pelvic fractures increased between 1970 and 2013 from 33 (number) and 73 (incidence) to 1055 (number) and 364 (incidence). ^3^ Nonetheless, conservative treatment is still the mainstream procedure for the treatment of FFP in the elderly. Loggers et al. ^4^ retrospectively investigated 117 elderly patients with FFPs and showed that 49% lost their independent mobility status, 40% failure to return to pre‐injury functional status, and the 1‐year mortality rate was 23%. FFPs result in considerable morbidity and mortality and as well as massive financial burden on the already strained health systems throughout the world. There is no question that as the population ages the absolute number of FFPs will continue to rise in China. Understanding trends of FFPs will facilitate better clinical care of older patients by orthopedic surgeons and better allocation of resources by policy makers.
FFPs were different in many ways from that of adolescents and adults with pelvic ring disruptions and has been greatly advanced in recent years. The definition of FFPs, trauma mechanisms, hemodynamic situation, clinical characteristics, primary and definitive treatments, bone density, fracture morphology, and classification and the minimally invasive surgical treatment strategies are unknown and not comparable. It should be paid more attention to this new and growing entity of pelvic injuries with population aging. Only in this way, we can better understand characteristics and investigate the most appropriate therapeutic options, surgical alternatives and long‐term outcomes. ^5^ , ^6^ , ^7^ , ^8^ , ^9^ , ^10^ , ^11^ , ^12^ Therefore, the Trauma Orthopedic Branch of Chinese Orthopedic Association, the External Fixation and Limb Reconstruction Branch of Chinese Orthopedic Association, and the National Clinical Research Center for Orthopedics, Sports Medicine, and Rehabilitation jointly invited various experts for consultation. The grades of evidence provided by the literature were classified according to the methods recommended by the workgroup of Grading of Recommendations Assessment, Development, and Evaluation (GRADE) and various other workgroups. Finally, 22 questions that were the major concerns of the orthopedists in China were addressed during screening. After further evidence searching, quality assessment of evidence, and deciding on the directions and strengths of recommendations, 22 recommendations were formulated. ^13^ , ^14^ Briefly, the recommended items 1–3 were for the epidemiological characteristics, items 4–7 were for the diagnosis and differential diagnosis, item 8 was for classifications, and items 9–22 were for the minimally invasive surgeries and drug therapies for FFP in the elderly. These guidelines aimed to improve the standardization and normalization of diagnosis and treatment of FFP in the elderly in China (Fig. 1).
Fig. 1 Flow chart of assessment and treatment of fragility pelvic fractures in the elderly
People aged ≥60 years were defined as the elderly according to the World Health Organization (WHO) and the working criteria in China. ^1^ , ^15^ , ^16^
Osteoporosis (OP) is a systemic metabolic skeletal disease characterized by low bone mass, microarchitectural deterioration of bone tissue, increased bone fragility, reduced bone strength, and consequently increased fracture risk. ^17^ , ^18^ , ^19^ The Guidelines for diagnosis and treatment of osteoporosis defined the osteoporotic fractures as the bone fractures in patients with primary OP, caused by mild violence in daily living, decreased the bone density, bone mass, and bone strength. The most common sites of osteoporotic fracture include the spine, hip, distal radius, proximal humerus, and pelvis. ^20^
Stress fractures, also known as fatigue fractures, refer to chronic bone injuries caused by the effects of persistent, long‐term, or repeated abnormal stress on bone mass with normal structures. The stress fracture mainly occurs at weight‐bearing sites, such as tibia, fibula, and metatarsal bones. ^21^
Pelvic insufficiency fractures occur in elderly patients with osteoporosis. These injuries may be the result of a fall or the result of no particular injury. Patients commonly complain of symptoms of low back and buttock pain. Sacral and iliac insufficiency fractures are specific stress fractures caused by persistent and continuous stress from physiological loading on the sacrum and ilium in daily living. ^22^ , ^23^ The common causes of pelvic insufficiency fractures include severe OP, radiotherapy of the pelvis, ^24^ long‐term immobilization in bed, long‐term use of glucocorticoids, ^25^ vitamin deficiency, ^26^ , ^27^ and long segmental fixation of lumbar vertebrae. ^28^ , ^29^
Fragility fractures result from mechanical forces that would not ordinarily result in fracture, known as low energy trauma. The World Health Organization (WHO) has quantified this as forces equivalent to a fall from a standing height or less. Several studies suggested that both osteoporotic fractures and insufficiency fractures should be included in the fragility fractures in the elderly. ^15^ , ^16^ , ^17^ , ^18^ , ^19^ , ^20^ , ^21^ Among these guidelines, FFPs in the elderly were defined as low‐energy injuries or stress in daily living that induced osteoporotic or insufficiency fractures of the pelvis in subjects aged ≥60 years. These guidelines were not suitable for pelvic fractures in the elderly caused by high‐energy injuries.
Recommendation The average age of pelvic fragility fractures occur is 80–90 years old, which is characterized by high incidence, high disability and high mortality (Grade of evidence and 1A).
The incidence of FFPs in the elderly is increasing gradually with the aging society. There is a marked female predominance and considerable morbidity and mortality in FFP. FFP has three high morbidity, high disability and high mortality.
Evidence from FFPs account for two‐thirds of pelvic ring injuries seen in the general population including all ages. Likewise, FFPs in patients over 60 years are low energy and osteoporotic in nature in 94% of cases. The prevalence of FFPs increases gradually with increasing age, peaks in subjects aged 80–90 years, and is substantially higher in females than males. ^15^ , ^30^ The mechanism of patients with FFP is completely different from that of adolescents and adults with pelvic ring disruptions. The highest trauma mechanism of FFPs is a fall from a standing position, even coughing or sneezing has provoked fragility fractures in some patients. ^31^ Park et al. ^32^ reviewed 325 patients with sacral fragility fractures from 2001 to 2014 with an average age of 69.4 years, and the 6‐month mortality rate was 9.8%, the one‐year mortality rate was 17.5%, and the 3‐year mortality rate was 25.5%. Loggers et al. ^4^ retrospectively analyzed 117 patients over 65 years old with osteoporotic pelvic fractures, in‐hospital mortality rate of 5%, 1‐year mortality rate of 23%, and 40% could not recover their pre‐injury mobility. A number of literatures have reported that the one‐year mortality rate of FFPs was 9.5%–18.9% in all patients over age 65 years to as great as 39% in elderly patients over age 90 years who sustain a pelvic ring injury. Multivariate statistical studies have confirmed that FFP was an independent risk factor of mortality in elderly patients. ^18^ , ^33^ , ^34^ , ^35^ , ^36^
Recommendation FFPs in the elderly are mainly caused by low‐energy accidents and the lateral compression fracture pattern is common (Grade of evidence and 1A).
The most typical trauma mechanism was a fall from a standing or sitting position. Due to the low‐energy trauma mechanism, lateral compression fracture pattern was common and concomitant lesions of the soft tissues did not occur frequently. The ipsilateral innominate bone was pushed towards the contralateral bone, resulting in a horizontal fracture of the superior pubic ramus. The lateral fracture fragment overrides the medial fragment. In the dorsal pelvic ring, a crush zone is present at the anterior part of the sacral ala.
Evidence from A single‐center study ^3^ investigated 816 patients with pelvic fractures between 2012 and 2017, of which 494 (60.5%) elderly patients had pelvic fractures, including 288 (58.3%) with rotationally unstable fractures and 81 (16.4%) with vertically unstable fractures. Wagner et al. described that in the elderly with FFPs, the anterior pelvic ring fractures caused by lateral stress were characterized by fractures of the unilateral or bilateral superior and inferior pubic rami with lateral displacements, while pelvic floor and sacroiliac ligament were integrated. Low‐energy accidents are the rule and domestic falls are typical. ^37^ , ^38^
Recommendation The dynamic assessments of fracture morphology and progress of instability are recommended. (Grade of evidence and 1B).
The changes of fracture morphology and progress of instability repeatedly observed over time in patients with FFP. The natural history of FFP was one of slow but continuous progress. Triggered by repetitive smaller stress in daily activities, an increasing number of bone structures are damaged that lead to more complex fracture patterns and greater instability. For pelvic insufficiency fractures or posterior ring fractures without displacement, more attention should be paid to the new and growing entity of pelvic injuries. Only in this way, is it better to understand their characteristics and investigate the most appropriate therapeutic options, surgical alternatives and long‐term outcomes.
Evidence from Rommens et al. ^29^ reported 148 elderly patients with FFPs, and further displacement of fracture fragments were detected in 21 patients (14.2%). Thirteen of 21 patients continued the conservative treatment and achieved fracture healing, and 8/21 patients changed the treatment strategy to minimally invasive surgery and healed. Ueda et al. ^39^ demonstrated that the high‐risk factors of progress of instability include female gender, severe OP, and persistent pain, and dynamic assessments were suggested for the elderly with FFPs. Triggered by repetitive smaller traumas, a large number of bone structures were damaged, leading to complex fracture patterns and instability of pelvis. Rommens and Hofmann recommended a re‐assessment for patients with persistent pain for 6–8 weeks after trauma or progressively aggravated pain. ^33^
Recommendation Pubic fractures with involvement of the posterior pelvic ring are common fractures in patients with FFP. (Grade of evidence and 1A).
The pelvis is a ring composed of bone and ligaments, and pelvic fractures generally occur at the pubic rami and sacral. Nearly all cases with fractures of the pubic rami do have a lesion elsewhere within the pelvic ring. With fractures of the superior or inferior rami, the pubic bone near the symphysis, and diastasis of the symphysis are detectable, plain radiographs have poor sensitivity to the detection of fractures in the dorsal pelvic ring. The presence of anterior ring fractures with displacement was accompanied by the posterior ring fractures.
Evidence from X‐rays still remains the primary imaging modality to assess the FFPs in the elderly. Fractures of the pubic rami were discovered while the accompanying injuries at the posterior ring could be missed easily. Anatomical studies have confirmed that fractures at the anterior ring with displacement are accompanied by injuries of the posterior ring, which can be manifested as fractures of sacral ala or injuries of the sacroiliac ligament. ^40^ Rommens et al. ^33^ showed a single‐center study, which included 148 elderly patients with FFP, including 118 cases (79.7%) with both anterior and posterior ring fractures and 36 cases (24.3%) with bilateral posterior ring fractures. Rommens et al. ^12^ retrospectively studied 245 elderly patients with FFPs fractures, including 44 cases (18.0%) of simple anterior ring fractures, three cases (1.2%) of simple posterior ring fractures, and 198 cases (80.8%) of both anterior and posterior ring fractures.
Recommendation Differential diagnosis includes lumbosacral degeneration, trauma, inflammation, or tumor‐induced lower back pain (Grade of evidence and 2C).
The clinical manifestations of patients with FFPs are completely different from that of adolescents and adults with pelvic ring disruptions. Elderly patients suffer from pain in the groin or at the pubic symphysis and in the lower back or the sacral region. The pain may irradiate to the lower extremities. Most patients are immobilized by pain, but some patients are still able to walk slowly with walking aids. Differential diagnosis includes chronic lower back pain, lumbosacral degenerative arthritis, spinal deformity and lumbar degenerative diseases.
Summary of Most patients with FFPs had a definite history of trauma and pain at the site of fractures. The site of pain varied according to the site of fracture. The common pubic rami fracture may present pain at the hip, groin, buttocks, or even thigh. There is localized pain on stress on clinical examination. Dorsal compression pain near the sacroiliac joint indicates a dorsal pathology. Simultaneous lateral‐to‐medial compression on both iliac wings may also induce anterior and/or posterior pelvic pain. Bruises or hematoma can be found in some patients. ^41^ , ^42^ The majority of the patients need to be immobilized in bed, but some could still walk, and the pain worsened when position was changed. Patients with pelvic insufficiency fractures have no history of trauma, while physiological activities, such as long‐term chronic cough or sneezing, could induce stress fractures, which have a prolonged disease course, a wide range of pain, and are difficult to be distinguished from chronic lower back pain, lumbosacral degenerative arthritis, lumbosacral tumor, local sacral radiotherapy, and pain following long segmental lumbosacral fusion. The combination of imaging examinations, such as CT scanning and MRI, could help with the differential diagnosis. ^3^ , ^29^ , ^33^
Recommendation The X‐ray images of the anteroposterior view of the pelvis, the pelvic inlet and outlet views, and coronal and sagittal CT reconstruction are recommended (Grade of evidence and 2B).
X‐ray imaging plays a pivotal role in assessing the FFPs as it enables their detection, confirmation, and grading in the elderly. Three views of the anteroposterior view of the pelvis, the pelvic inlet and pelvic outlet views are obtained at admission. Plain radiographs have poor sensitivity for the detection of fractures in the dorsal pelvic ring. CT provides a far better assessment of fragility fractures of the sacrum and no special positioning is necessary.
Summary of Due to the blockage of abdominal soft tissues and contents and the nondisplaced fracture, fractures at the posterior ring could be easily missed by pelvic X‐ray imaging. Previous studies recommended pelvic CT scanning, especially coronal and sagittal reconstructions, which display the continuity of the bone mass at the posterior pelvic ring and accurately assess pelvic stability. ^40^ Rommens et al. ^33^ performed imaging examinations for 245 patients with FFP and found that 196 (80%) patients had fractures at the anterior and posterior ring. CT scanning was recommended for all patients with pelvic fractures. Coronal reconstructions help in displaying the fractures at sacral ala, while sagittal reconstructions appreciate the fracture morphology and degree of instability.
Recommendation MRI should be taken into consideration whenever the origin of pelvic pain remains unclear after X‐rays and CT examinations in which no lesion has been discovered. (Grade of evidence and 2B).
Conventional X‐rays and CT examinations still play important roles in the diagnosis of fractures and assessment of instability of pelvis. Due to its superior sensitivity, MRI should be performed in cases with negative the serial imaging examinations, and with a high clinical suspicion of fragility fractures of the pelvic ring. Moreover, MRI has an advantage in differentiating between different causes of fragility fractures of the pelvis.
Summary of A previous study ^43^ reported that pelvic MRI examination was recommended in patients when neither X‐ray nor CT could explain the lower back pain or pain in inguinal region. The sensitivity of MRI in diagnosing pelvic fractures is almost 100%, which could differentiate pathological fractures, inflammatory diseases, and pain induced by metastatic tumors. The sensitivity of bone scanning for FFPs in the elderly is 96% and the specificity is 92%. However, with MRI widely available nowadays, scintigraphy is not used to diagnose the fragility fractures of the posterior pelvic ring in a clinical routine. ^44^
Recommendation The FFP classification is based on morphological criteria and gives hints for treatment strategies. (Grade of evidence and 1A).
Fragility fractures are the result of low‐energy trauma instead of high‐energy trauma, which are typical for pelvic ring lesions in adolescents and adults. The classification of FFPs in the elderly should consider the anatomical features, mechanisms of injuries, and the stability of the pelvic ring. The anatomical features and mechanisms of injuries in FFP in the elderly are different from high‐energy injury‐induced pelvic fractures. Both Tile and Young–Burgess classifications are based on the mechanisms and degrees of pelvic instability of high‐energy injuries, which are not suitable for FFPs in the elderly. Due to the specificities of bone mass and multiple comorbidities of elderly patients, whether the same criteria should be applied to young patients and the elderly to assess the stability of pelvic fractures is still debatable. The FFPs classification is based on the morphology of the FFPs in the elderly and pelvic stability and is a common method for assessing fracture stability and guiding treatment strategies in clinical practice.
Summary of The anatomical features of the pelvis in the elderly include trabecularization of the cortex of sacral ala, alar void, and areas of complete bone density loss. Another presentation is calcification of ligaments and joint space narrowing, while the ligament remains strong but less elastic. ^45^ , ^46^ The lateral stresses are mainly focused on sacral ala and the intersections between the cortical bones and cancellous bone on the bilateral sides of pubic symphysis. ^45^ , ^46^ , ^47^ The most common types are compression fractures of sacral ala and those at the intersections between cortical bones and cancellous bone on the bilateral sides of pubic symphysis. Due to the differences in the anatomical structures of the pelvis and the mechanisms of injuries, the Young–Burgess and Tile classifications are not completely suitable for FFP in the elderly. ^47^ Rommens and Hofmann ^33^ retrospectively analyzed the data of 245 elderly patients with low‐energy pelvic injuries between 2007 and 2013 and provided X‐ray and CT imaging‐based classification according to the morphological features and stability of the pelvic ring. The FFPs classification categorized the fractures into four mild unstable FFP (Type I FFP, with anterior ring fractures only and without posterior ring fracture), moderate unstable FFP (Type II FFP, with anterior ring fractures and unilateral posterior ring fractures, with no displacement), severe unstable (Type III FFP, with anterior ring fractures and unilateral posterior ring fractures that were accompanied by displacement), and extremely unstable (Type IV FFP, with anterior ring fractures and bilateral posterior ring fractures). Another study investigated 148 elderly patients with FFPs, including 30 (20.3%), 73 (49.3%), 9 (6.1%), and 36 (24.3%) patients with Type I, II, III, and IV FFP, respectively. A total of 111 (75%) patients underwent conservative treatment, and 37 (25%) patients underwent surgical treatment, including two (7%), 12 (16%), two (22%), and 21 (58%) patients with type I, II, III, and IV FFP, respectively. These findings suggested that the comprehensive classification provides a framework for distinguishing different types and levels of instabilities in the elderly. ^29^ Since then, numerous studies have used FFP classification to assess pelvic stability and guide treatment strategies. ^18^ , ^21^ , ^36^ , ^37^
Recommendation Monitoring of hemodynamics and vital signs is recommended at least during the first 24h after admission (Grade of evidence and 2B).
Hemodynamic instability in fragility fractures of the pelvis is rare. Case reports were identified FFP in the elderly could be accompanied by vascular injuries or hematoma, which could lead to hemodynamic instability. There must be a high index of suspicion on bleeding in patients with fragility fractures of the pelvis, who are treated with long‐term use of anti‐platelet or anti‐coagulation drugs. Hemodynamic monitoring at least during the first 24 h after admission was recommended.
Summary of Rommens and Hofmann ^33^ retrospectively analyzed 245 elderly patients with FFPs over 5 years. Interestingly, none of these patients sustained life‐threatening bleeding, indicating that the FFPs in the elderly were low‐energy injuries rarely accompanied by hemodynamic instability. Dietz et al. ^41^ summarized eight FFPs elderly patients with major hemorrhage, and four were on long‐term anti‐coagulation treatment before the injury, including low‐energy fractures with nondisplaced or mild displacement. Angiography identified two patients with obturator artery or internal iliac artery rupture, and one patient each showed a rupture of the superior gluteal artery, external pudendal artery, inferior epigastric artery, and external iliac artery. The time of shock ranged from 2 to 72 h after injury (average: 5 ± 27.7 h), and four patients died due to unstable hemodynamics. Thus, it was recommended that for elderly patients with FFPs on long‐term oral anti‐coagulation or anti‐platelet treatment, the hemodynamics and vital signs should be monitored within 24 h post‐injury.
Recommendation The emergency stabilization and pain management are recommended to relieve pain and simplify nursing before definitive treatment. (Grade of evidence and 1B).
Elderly patients with FFPs are accompanied by moderate or severe pain, which could influence the physiological status and complications of the patients. Emergency stabilization and pain management reduce the need for blood transfusions and alleviate the pain. Pelvic sheets and NSAIDs are the simplest constructs and procedures. Damage control measures, such as pelvic clamping, external fixation, pelvic packing and angiography are generally not necessary.
Summary of The main symptom at admission is pain which should be treated first and adequately. Previous studies have reported that effective management of bleeding is the primary and foremost procedure for reducing mortality. Due to the mechanisms of injuries, features of fractures, OP, pelvic C‐clamp and external fixation or emergent angiograph are technically more difficult than applying a pelvic sheet or binder in patients of FFP, and serious complications have been described in several publications. ^29^ , ^41^ , ^48^ Due to the pressure on skin that may be traumatized, pelvic binders and pelvic binders should not remain in place for longer than a few hours. ^49^ , ^50^
Recommendation Conservative treatment is suitable for patients with type I and II but dynamic assessment is required (Grade of evidence and 2B).
FFP type I and II are usually treated conservatively. Bed rest, pain control, and early mobilization with weight‐bearing as tolerated are recommended. The patient should be kept in bed until the pain is under control. Assisted physiotherapy should commence as soon as possible in whole procedure. Management consists of Vitamin D, calcium supplementation, antiresorptive drags and the anabolic agent parathyroid hormone. Mechanical deep vein thrombosis prophylaxis and pharmacologic prophylaxis are given according to the guidelines until the patient is properly mobilized. Centrally acting analgesics, such as paracetamol and opioids are recommended until pain control. The patient is allowed to start mobilization with weight bearing as tolerated when pain subsides. Mobilization should start with the assistance of physiotherapists and not forced as this may increase the risk of fracture progression or displacement again.
Summary of Scheyerer et al. ^51^ investigated 177 geriatric patients with pelvic fractures. The findings showed that the incidence of type I fracture was approximately 3.2%, and all patients underwent conservative treatment. This finding also showed that X‐ray imaging could easily miss the fractures of the posterior ring, thereby necessitating axial CT scanning. Type II fractures are fractures without displacement of the posterior ring. Most previous studies used conservative treatment because of stability of the whole pelvic ring, and the patients should be admitted to the ward and maintained in bed until the pain is under control and the patient can start mobilization. ^52^ Early mobilization under good pain control is recommended. Subsequently, dynamic examinations by X‐ray and CT of the pelvis are recommended. Surgical treatments should be considered if fracture progression or displacement is increased and the intensity of pain is unchanged or the patients experience substantial difficulties in activities. ^53^
Recommendation Surgical treatment should be considered in case of type III and IV fracture with severe, untreatable pain, persisting pain and delayed or non‐union fracture. (Grade of evidence and 2B).
The main goals of surgical treatment should be early ambulation and optimum functional recovery. The type of surgical treatment is dependent on the degree and the localization of instability. The FFP classification provides clear recommendations with type III and IV fractures for surgery. If pain aggravates within the first week after conservative treatment of type I and type II fractures, surgical treatment should be considered. Elderly patients with FFPs who cannot stay in bed for a long time are the relative surgical indications. The general condition of patients without hemodynamic problems and severe comorbidities should be optimized before surgery.
Summary of With the advancements in the techniques of imaging and the extensive applications of three‐dimensional printing, navigation, robot‐assisted surgery, and minimally invasive reduction for pelvic fractures, minimally invasive surgeries for pelvic fractures are evolving. ^54^ The goals of surgical treatments include functional reduction, stabilizing the pelvis, alleviating the pain, and reducing the time of immobilization in bed. ^49^ Therefore, for elderly patients with unstable pelvic rings, that is, type III or IV FFP or type II FFP that failed conservative treatment, minimally invasive reduction and concurrent fixation of posterior and anterior rings are the trends for future treatments. ^34^ , ^53^ , ^54^ Typically, the FFPs in the elderly are accompanied by non‐displacement, for which functional reduction and minimally invasive fixation form the basis for early painless functional exercises. Thus, conventional minimally invasive reduction and fixation techniques are suitable for elderly patients with FFP. Proper close or open reduction are essential for a good outcome. After functional reduction is achieved and confirmed by image intensifier, surgical techniques can be used. Simultaneous fixation of the anterior and posterior pelvic rings is recommended.
Recommendation Manual reduction or reduction with pelvic reduction frame is recommended (Grade of evidence and 2B).
Appropriate reduction is the premise and basis of minimally invasive fixation. FFPs are usually accompanied by nondisplaced or slightly displaced fractures and might not necessarily require anatomical reduction in the elderly. It can be reduced by femoral traction for the vertical displacement. Bilateral percutaneous insertion of Schanz screws into the supraacetabular area of iliac bone. Closed reduction and stabilization of the pelvic ring by compression and application of a connecting rod under image intensification. In addition, percutaneous reduction tools such as top rods, gripping forceps, and bone hooks can be used to help complete accurate reduction of complex fractures. For fractures with slight displacement, techniques of reduction using a minimally invasive pelvic reduction frame are recommended. The supine position facilitates anesthesia and intraoperative monitoring, using the imaging operating bed equipped with imaging devices that could help the reduction via a minimally invasive pelvic reduction frame.
Summary of Currently, the most mature percutaneous minimally invasive reduction techniques are effectuated via the Starr reduction frame ^55^ and the multidimensional pelvic reduction frame modified by the PLA General Hospital. ^56^ The pelvis and reduction frame are fixed on the operating table first, and the contralateral side of the pelvis is used as the reference. Then, supraacetabular half pin traction is performed to release the interlock of the fracture ends, and LC‐2 half pin is used for traction and reverse rotation to the direction of fracture displacement, thus achieving the multidimensional reduction of the affected pelvis. A specific rod with a ball‐shaped end or femoral traction could be used to assist the reduction. X‐ray images of the anteroposterior view, pelvic outlet view, and pelvic inlet view can be used to assess the reduction of fracture. ^56^ , ^57^ , ^58^ , ^59^
Recommendation Meticulous preoperative planning increases the safety and effectiveness of minimally invasive reduction and fixation (Grade of evidence and 2B).
Various parameters, such as preoperative enema, supine position, radiolucent operation table, C‐arm, and imaging angles, could influence the quality of images. This enables free movement of the C‐arm for intraoperative pelvic inlet and outlet views. The standardized preoperative bowel preparation and imaging techniques and the systemic training of the team could improve the efficiency of surgery, shorten the operation time, increase surgical efficacy, and reduce surgical complications.
Summary of FFPs in the elderly usually do not have or exhibit slight displacement. The main goals of the operation are functional reduction and minimally invasively fixation under precision imaging to alleviate pain and facilitate early ambulation. The supine position, use of a whole‐body imaging operating table, and stretching out and abduction of the upper limbs on the arm holders are recommended, and the lower limbs could be connected to a traction device. ^55^ , ^56^ Intraoperative imaging assessment is vital, and metal instrumentation in the field of fluoroscopy should be avoided as so as possible. ^9^
Recommendation Standard imaging techniques underlie the minimally invasive surgeries of FFP in the elderly (Grade of evidence and 2B).
The most commonly used positions for imaging included the anteroposterior view, pelvis outlet view, pelvis inlet view, obturator oblique view, LC‐2 long axis view, obturator outlet view, iliac inlet view, tear‐drop view, sacroiliac inlet view, and anteroposterior view of iliac ala. The surgical team and radiologists should be familiar with the corresponding imaging techniques and significance. As evaluation of 2D views can be limited due to anatomy and superposing structures, intraoperative 3D imaging has become common in the last decade.
Summary of The pelvis inlet view could assess the forward and backward displacement of the pelvic ring and the sacroiliac screws in the bony channel between the presacral cortex and the sacral canal. The pelvis outlet view could help in assessing the pelvic ring's vertical displacement, and the sacroiliac screws are in the bony structure of the sacral ala and sacral vertebral bodies. The lateral pelvic view clarified the site of sacroiliac screwing and assessed whether the sacroiliac screws were inserted on the outside of the presacral cortex. The iliac inlet view displayed the direction of the screws between the inner and outer plates of pubic rami on the axial images. The obturator outlet view displayed the length and direction of the screws between the upper and lower cortexes of pubic rami on coronal images. The tear‐drop view allowed the surgeon to decide the insertion sites of the LC‐2 screws and INFIX iliac screws. The iliac oblique view and the LC‐2 long axis view could be used to assess the insertion and length of LC‐2 screws and INFIX iliac screws in the vertical direction in the channel. The anteroposterior view of sacral ala was used to assess the direction of LC‐2 screws and INFIX iliac screws between the inner and outer sacral plates. The axial view of the iliac 1 vertebral pedicle could be used to assess whether the sacroiliac screws are inserted in the channel and in safe regions. ^60^ , ^61^
Recommendation Percutaneous channel screws, minimally invasive plate screws, INFIX and bone cement techniques were recommended for elderly patients with unstable FFP (Grade of evidence and 2B).
Among several fixation techniques, the minimally invasive surgery technique is increasingly recognized as the first choice in most FFPs cases during the last few decades. The methods include percutaneous channel screw fixation system, INFIX, percutaneous locking plate for pubic symphysis, percutaneous anterior ring bridging plate, and percutaneous posterior interiliac plate. The surgeon must be able to accurately evaluate and understand the nature of the injury and be familiar with the anatomy of the pelvic ring, stabilizing structures, resisting forces, reduction techniques, and use of different reduction tools, and have a thorough knowledge and understanding of the various image intensifier views to assess the state of reconstruction.
Summary of Routt et al. ^61^ first reported the technique of percutaneous sacroiliac screw implantation in the supine position and created a precedent for the percutaneous minimally invasive surgeries of posterior pelvic ring injuries. Thereafter, other techniques, including the use of percutaneous LC‐2 channel screws and public rami screws, have emerged. The feasibility and effectiveness of these percutaneous screwing techniques have been confirmed by various studies, which provided a basis for minimally invasive surgeries. ^56^ , ^62^ , ^63^ However, using channel screws for fixation involves a high risk of screw loosening; thus, bone cement could be used to improve the fixation by channel screws. ^64^ , ^65^ , ^66^ Sacroplasty was recommended in well‐selected patients as a secondary treatment for sacral insufficiency fractures after unsuccessful conservative therapy. The crosslinking of bone cement and bone trabecula restores the stability of fracture ends and alleviates the pain. ^64^
Recommendation Bone cement augmentation can be recommended in well‐selected patients as a secondary treatment for pelvic insufficiency fractures after unsuccessful conservative therapy (Grade of evidence and 2B).
Implementing the use of bone cement augmentation techniques with a specific indication for elderly patients with poor bone quality. Augmentation using polymethylmethacrylate (PMMA) or tri‐calcium phosphate bone cement is one method to increase primary implant stability. Cement augmentation of iliosacral screws is a minimally invasive procedure that efficiently reduces pain after sacral insufficiency fractures in the elderly.
Summary of Kim et al. ^64^ used sacroiliac screws for fixation of FFP in 110 patients and observed screw loosening in 19 (17.3%) patients after the operation. The study also suggested that implanting sacroiliac screws into the cancellous bone of the S1 vertebral body and Denis zone II fracture was a high‐risk factor for loosening of sacroiliac screws. The long channel screws, anatomic locking plates, and bone cement augmentation techniques are commonly used measurements to prevent postoperative loosening and ineffective internal fixation. The bone cement augmentation technique utilizes through‐the‐screw cement augmentation or augmentation prior to screw placement. Thus, augmentation prior to screw insertion causes several complications due to cement leakage. ^65^ Uniform cement distribution is achieved through various side openings and the tip of the screw. In the case of leakage, cement injection should be stopped immediately. Thus, image monitoring is essential in the procedures to prevent cement leakage. ^66^ , ^67^
Recommendation The purpose of fixation for the anterior pelvic fragility ring is to mitigate incapacitating pain, facilitate mobilization and rehabilitation, and prevent functionally significant pelvic malunion and nonunion. (Grade of evidence and 2C).
Surgical treatment of anterior pelvic fragility fractures is indicated to improve stability of the pelvic ring after fixation of the posterior pelvis in unstable fracture variants. The most commonly used anterior ring fixation techniques include pubic symphysis plate, anterior ring bridging plate, INFIX, and retrograde medullary superior pubic ramus screw fixation. INFIX allows minimally invasive bridging of the anterior pelvic ring, ideally situated in transforaminal or far lateral extraforaminal pubic rami fractures. The connection rod is at the bikini line, slightly higher than the abdominal appearance, which prevents the compression of femoral nerve and blood vessel bundles and reduces postoperative complications.
Summary of As the fracture line at the anterior ring is close to pubic symphysis, there is a high risk of loosening or implant failure when the whole length of the anterior column corridor is not used. Failure of fixation has been reported to be about 15% in several pelvic ring fractures. ^68^ , ^69^ , ^70^ Pubic symphysis plate is suitable for unilateral or bilateral pubic ramus fractures. After Pfannenstiel incision or midline longitudinal incision is made, the long reconstruction plate or locking plate is used for fixation superior to the pubic symphysis. ^30^ For the anterior ring bridging plate, the incision encompasses the Pfannenstiel incisions anterior to and between the bilateral iliac ala, not requiring to expose the pubic symphysis. After modeling, the plate is inserted through the subcutaneous approach and fixed at the bilateral iliac ala or pubic body in the middle. ^71^ , ^72^ INFIX internal fixation 8–10 cm pedicle screws are implanted subcutaneously in the tissues through a cannula along the bilateral LC‐2 screw channels, and the connecting rod is inserted subcutaneously to connect and lock the bilateral pedicle screws. This method is suitable for fractures of pubic rami with unstable anterior rings caused by lateral crushing. Previous studies demonstrated that this fixation has high stability than external fixation, similar to the double‐plate fixation, with a high postoperative satisfaction degree in patients. ^73^ , ^74^ During the procedures, the lateral femoral cutaneous nerve should not be injured, and the rod should be placed in the Scarpa fascia layer to prevent the compression of the femoral nerve and blood vessel bundle. Retrograde transpubic screw fixation is adequate for high‐level pubic rami fractures, wherein the insertion site is at the pubic tubercle. The guide pin and screws are implanted in the medullary space of superior pubic rami under the guidance of imaging at the obturator outlet and pubis inlet positions, avoiding the insertion through the pubic cortex or into the hip joint.
Recommendation Minimally invasive posterior ring fixation methods, such as sacroiliac screws, plate screw systems, and interiliac fixation systems were chosen according to the site of the posterior ring fracture, the degree of displacement and pelvic instability (grade of evidence and 2B).
FFP Type II is often stabilized with a percutaneous procedure, whereas FFPs Types III and IV are usually stabilized followed by closed or open reduction. Iliosacral screw osteosynthesis, bridging plate osteosynthesis, transsacral positioning bar and angle stable plating are valid alternatives. In FFP Type IV lesions, bilateral stabilization or iliolumbar fixation are recommended. Iliosacral screw fixation can be regarded as a valid and safe minimally invasive technique for stabilization of fractures of the sacrum and fracture‐dislocations of the sacroiliac joint in FFP. Alternatives for invasive treatment are sacroiliac screw osteosynthesis, sacroplasty, bridging plate osteosynthesis or insertion of a transsacral positioning bar. For patients with bilateral iliac fractures, the posterior bridging plate and minimally invasive adjustable plate (MIAP) for the posterior pelvic ring is recommended, of which the unique anatomical designs could address the disadvantages of the posterior interiliac reconstruction plates.
Summary of The anterolateral approach provides surgical access to the iliac fossa as far as the pelvic brim. For the elderly with type IIa or IIIa, the lateral window through ilioinguinal approach is used, and plates or screws are used for fixation. In the elderly with type IIb or IIIb, if the fracture line affected the iliosacral displacement, the lateral window through ilioinguinal approach was selected, and plate or screw or percutaneous iliosacral screws were used for fixation. ^75^ , ^76^ , ^77^ , ^78^ Dorsal In the elderly with type IIIc unilateral sacral fractures, minimally invasive reduction or sacral reduction through the dorsal approach is employed, and then iliosacral screw fixation or posterior approach plate fixation is performed. ^79^ Posterior bridging plate and posterior pelvic ring MIAP: the lateral plates of the Z‐shaped plate are attached to the medial posterior iliac crest, the upper plate is fixated at the posterior superior iliac spine, and the lower plate is fixed above the dorsal sacrum. The cannulated connecting rod is implanted in the percutaneous tunnel and connected to the bilateral Z‐shaped plates. The connecting rod could be extended or shortened under the guidance of imaging for the reduction and fixation of the posterior pelvic ring. ^80^
Closed reduction and percutaneous minimally invasive iliosacral screw fixation is the most commonly used fixation technique for the posterior ring in the elderly with FFP. ^75^ , ^76^ , ^77^ , ^78^ , ^79^ , ^80^ , ^81^ Percutaneous iliosacral screw fixation is a safe and effective method for posterior pelvic ring injuries. ^12^ , ^82^ For complete posterior pelvic injuries, multiple transsacral iliosacral screws could enhance the fixation intensity. ^83^ , ^84^ Moreover, transsacral screws for fixation have better clinical effects than using two unilateral iliosacral screws. ^85^ Compared to unilateral iliosacral screws, transsacral screws do not induce additional pain or functional damage. ^86^ , ^87^ For patients with iliac dysplasia, navigation‐assisted screw implantation has more significant precision than regular screw implantation. ^88^ , ^89^
Recommendation X‐ray, CT, bone scan and MRI should be checked for elderly patients with severe pelvic pain and immobilization, and conservative care and minimally invasive fixation are recommended. (Grade of evidence and 2C).
Sacral insufficiency fractures (SIFs) are common sources of back pain in the elderly and are associated with significant morbidity due to poor recognition and delay in the diagnosis in the elderly. SIFs are usually accompanied by the pubic rami and parasymphyseal region insufficiency fractures. Risk factors for SIFs include osteoporosis, osteopenia, rheumatoid arthritis, corticosteroid use, radiation therapy, renal osteodystrophy, osteomalacia, Paget's disease, hyperparathyroidism, hip joint arthroplasty or other pathology, and lumbosacral spinal fusion. For elderly patients with persistent back or hip pain or with a history of long‐term glucocorticoid treatment, pelvic radiotherapy, or long‐segmental spinal fixation, MRI or ECT imaging should be performed as necessary. MRI is more sensitive than CT and shows hypointense signal on T1‐weighted sequences and hyperintensity on T2‐weighted or short tau inversion recovery sequences. Accepted treatments include nonoperative rehabilitation, sacroplasty, iliosacral screw fixation, transsacral bar or screw fixation, transiliac internal fixation, and lumbopelvic fixation.
Summary of Pelvic insufficiency fractures in the elderly have insidious disease onset, and the clinical manifestations include persistent back or hip pain, which worsens after activities but is alleviated after rest or immobilization. Conventional radiographs have a poor sensitivity between 20% and 38% because of osteopenia and overlying bowel gas, while CT scan increases the sensitivity up to 58% for detecting insufficiency fractures. MRI and bone scintigraphy confirm the diagnosis of posterior ring fractures. MRI manifestations include low signal on T1 image, high signal of spinal edema on T2, and low signal of newly regenerated bone or bone trabecula, which shows confounding signals. Bone scintigraphy has the highest sensitivity for the diagnosis of sacral fractures, wherein elevated radioactive uptake is observed 6–72 h after injury, and the typical manifestation is the H‐or butterfly‐shaped radioactive uptake region. ^90^ However, bone scintigraphy is not a routine examination. The most common treatments for pelvic insufficiency fractures in the elderly include concurrent minimally invasive fixation of the anterior ring, bone cement augmentation screwing of the posterior ring, and sacroplasty.
Recommendation Indications for sacroplasty include sacral insufficiency fractures or newly occurred sacral fractures with no displacement or suitability for closure reduction. The procedures involve the risk of bone cement leakage (Grade of evidence and 2B).
Sacroplasty aims to alleviate pain, reduce the need for pain medication, facilitate early mobilization, and decrease the length of hospital stay. Percutaneous sacroplasty requires a slight amount of cement filling into the fracture gap; the crosslinking of bone cement with bone trabecula restores the stability of fracture ends and rapidly alleviates the pain. Cement leakage is one of the most common complications of sacroplasty. Denis zone I fractures of the sacral ala can be safely treated with PMMA, while zone II and III fractures carry the risk of cement extravasation through the foramen and injury to the S1 nerve root.
Summary of Gibbs and Doshi suggested that sacroplasty offers an immediate return to preinjury level of function compared to the alternative conservative treatment of immobilization with pharmacotherapy for pain relief. Furthermore, it might reduce several comorbidities, such as persistent pain, respiratory complications, and muscle atrophy that are presented with prolonged bedrest and conservative management of these injuries. ^70^ Several studies suggested placing the patients in the prone position, followed by a puncture between the sacral foramina and sacroiliac joint under the guidance of imaging until reaching the fracture line at sacral ala and infusion of 4–6 mL of bone cement. The leakage of bone cement into the fracture gap and the surrounding cancellous bone immediately enhances the stability of the fracture and alleviates pain. The 10‐year postoperative follow‐up showed that the pain alleviation rate was about 94%. The potential complications of sacroplasty include dural leak, hemorrhage, infection, damage to nerve roots, or injury to the lumbosacral plexus. ^70^ , ^88^
Recommendation Standardized adjuvant drug therapies are recommended and bisphosphonates are the preferred drugs for FFP treatment (Grade of evidence and 2B).
Early, sequential, long‐term adjuvant drug therapy should be administered in all elderly patients with FFP. Bisphosphonates have been extensively used in clinical practice due to their safety, effectiveness, and economic benefits.
Summary of FFPs in the elderly are the local presentation of senile asthenia syndrome. In a systemic review by Yoder et al., ^91^ the X‐ray, bone scanning, CT, and MRI images of 113 elderly patients with FFP were analyzed. The findings showed that the pelvic degeneration mainly manifested as reduced bone weight per unit volume, thinning of the bone cortex of bilateral sacral ala, resorption of trabecula of cancellous bone, fatty degeneration of spine, and formation of a mechanically weak region. Previous studies have demonstrated that OP, previous pelvic radiotherapy, rheumatoid arthritis, long‐term use of steroids, and menopause are high‐risk factors of FFP in the elderly.
Drug therapies include anti‐resorptive agents and bone‐forming agents. Anti‐resorptive agents include bisphosphonates (including alendronate sodium, risedronate sodium, sodium ibandronate, and zoledronic acid), selective estrogen receptor modulators, glucocorticoids, and denosumab. Bone‐forming agents mainly include parathyroid hormone analogs (Teriparatide). The commonly used drugs in clinical practice include bisphosphonates, recombinant parathyroid hormones, and denosumab. ^92^ , ^93^ , ^94^ Maintaining an adequate calcium and vitamin D intake through diet, supplementation, or both is a standard part of the treatment of osteoporosis. The indications for drug therapy include a history of fragility fractures, T value <−2.5 or T value > − 1 but <−2.5, and other risk factors. Previous studies have shown that drug therapy is effective in the treatment of osteoporosis and in the reduction of fracture risk. ^95^ , ^96^
This guide was developed in line with the conceptual and process framework for the construction of clinical practice guidelines by the American Academy of Medical Sciences (Institution of Medicine, IOM), the Guidelines Research and Evaluation Tool (Appraisal of Guidelines Research and Evaluation, AGREE II), and the WHO Guidelines Development Manual. The development process of this guide is conducted in strict accordance with the advance plan, and the reporting process of the guide refers to the Health Practice Guide Reporting Standard (Reporting Items for Practice Guidelines in Healthcare, RIGHT).
This guideline is applicable to patients with a suspected or definite diagnosis of FFPs.
The specialized medical staff of the secondary and tertiary medical institutions in China, including orthopedic doctors, geriatric doctors, rheumatologists, pain doctors, rehabilitation doctors and the corresponding specialized nurses, as well as the medical staff of the health care institutions.
This guide by the National Orthopedic and Sports Rehabilitation Clinical Research Center, the People's Liberation Army General Hospital Orthopedic Medicine, the Third Hospital of Hebei Medical University Orthopedic initiated and responsible for formulation, by the Chinese Medical Association of Bone Science Group and the Chinese Medical Association of External Fixation and Limb Reconstruction Group, methodology experts in the field of orthopedic guide to develop methodology and evidence evaluation support. It was launched on February 13, 2021, and was finalized on December 30, 2021.
This guide is registered on the International Practice Guide Registration Platform (http://www.guidelines-registry.cn; IPGRP‐2022CN266).
All members involved in the development of the guidelines made any statement of interests related to this guide and filled out the statement of interest form.
The formation process of clinical problems is conducted in strict accordance with the guideline clinical problem formation method and combined with the evidence‐based thinking of Delphi method. The main steps drafting the consultation items and outline, determining the members of the expert group, multiple letter inquiries and item revision, and the statistical analysis and feedback of the survey results. The guideline working group collected 116 questionnaires and 58 clinical questions through the first round of open questionnaire survey, including doctors from hospitals in different provinces and cities; then summarized the collected clinical questions, and finally obtained 46 clinical questions. Then the second round of survey, evaluated the importance of clinical problems (the importance of each clinical problem is divided into five levels, namely very important, more important, generally important, less important and uncertain), by assigning and summary of each importance level, finally will 40 clinical problems of importance sorting. Later, through the third round of discussion, the important clinical issues were deconstructed, deleted and integrated again, and the 22 clinical issues included in this guide were finally identified.
For the included clinical problems, they were deconstructed according to the EBM literature retrieval format. Evidence retrieval according to the solved clinical search database, including CNKI, CQVIP technology journal database, Wan fang database, Chinese biomedical literature database, PubMed, Embase and Cochrane Library database. The type of study was searched for, prioritizing the published systematic evaluation, meta‐analysis, RCT, cohort studies, and case–control studies within 5 years. With insufficient evidence or low level of evidence, the searches of systematic evaluation, meta‐analysis, RCT, and cohort studies, case and control studies published 5 years ago were added. The search was conducted using a pre‐designed strategy and with a rigorous assessment of the methodological quality of all eligible literature through the Cochrane collaboration tool, from library building until March 20, 2021. Further searches of the recently published evidence were conducted prior to drafting the main body of the guidelines, and the searches were updated on December 20, 2021.
Methodological quality evaluation using the methodological quality evaluation tools for systematic evaluation and meta‐analysis, the Cochrane risk bias evaluation tool for randomized controlled trials, and the Newcastle Ottawa Scale for observational studies. The literature rating criteria used in this guide evaluated the quality of the research evidence according to the recommended opinion grading (Grading of Recommendations Assessment, Development and Evaluation, GRADE) grading system working groups and other working groups. The level of evidence and the recommended strength of the study (Table 1) were comprehensively determined by combining the study design and other evidence characteristics (Table 2). The direction and intensity of the recommendation opinion were established through three rounds of Delphi method. There are 22 questions in this guide and 22 recommendations (Table 3).
Prior to the publication, the members of the Trauma Bone Science Group of the Chinese Medical Society and the External fixation and limb Reconstruction Group of the Bone Science Society of the Chinese Medical Society were reviewed, and the review opinions were replied and revised.
The full text of the guidelines is preferentially published in the Chinese Journal of Orthopedics. At the same time, the guideline development team plans to update the guidelines every 2 to 3 years.
After the guide is published, it will be disseminated through academic conferences or study classes. Specific modes of communication dissemination in orthopedic meetings and geriatric trauma training courses for 1–2 years; the guide will be published in newspapers, journals, singles, manuals, etc.; this guide will be publicized in Chinese and English, and disseminated on orthopedic online, medical orthopedics and other websites; further promoting the implementation of the guide through the implementation and evaluation of the guide.
Sun Tiansheng, Orthopedic Medicine Department of the PLA General Hospital.
Tang Peifu National Clinical Research Center for Orthopedics and Sports Rehabilitation.
Zhang Yingze, Orthopedics Department of the Third Hospital of Hebei Medical University.
Yu Bin, Department of Traumatic Orthopedics, Southern Hospital, Southern Medical University.
An Weijun, Ningxia Medical University General Hospital.
Bi Zhenggang, the First Affiliated Hospital of Harbin Medical University.
Cai Xianhua, General Hospital of the PLA Central Theater Command.
Cao Xuecheng, the 96th Hospital of the PLA Joint Logistic Support Department.
Zeng Bingfang, Shanghai Sixth People's Hospital.
Chai Yimin, Shanghai Sixth People's Hospital.
Chen Aimin, the Second Affiliated Hospital of Naval Military Medical University.
Chen Weigao, the Second Affiliated Hospital of Nanchang University.
Chen Yanxi, Trauma Center, Oriental Hospital, Affiliated to Tongji University.
Chen Zhong, the Second People's Hospital of Yunnan Province.
Dang Xiaoqian, the Second Affiliated Hospital of Xi'an Jiaotong University.
Ding Zhenqi, the trauma and Orthopedics department of the 175th Hospital of the Chinese People's Liberation Army.
East Jingming Tianjin Tianjin Hospital.
Fang Shiyuan, the First Affiliated Hospital of the University of Science and Technology of China.
Fu to the Affiliated People's Hospital of Peking University, China.
Gao Peng, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences.
Gu Liqiang, the First Affiliated Hospital of Sun Yat‐sen Medical University.
Guo Xiaoshan, the Second Affiliated Hospital of Wenzhou Medical University.
Huang Fuguo, Department of Trauma and Orthopedics, West China Hospital, Sichuan University.
Huang Lei, Beijing Jishuitan Hospital.
Ji Fang, the Ninth People's Hospital Affiliated to Shanghai Jiao Tong University.
Jia Yanfei, the Second Affiliated Hospital of Inner Mongolia Medical University.
Jiang Baoguo, Peking University People's Hospital.
Jiang Yu Heng, Orthopedics Medicine Department of the PLA General Hospital.
Jiang Xiyuan Beijing Jishuitan Hospital.
Kang Qinglin, Shanghai Sixth People's Hospital.
Kong Rong, the First Affiliated Hospital of the University of Science and Technology of China.
Li Jun, Peking University First Hospital.
Li ainan Department of Orthopedics, Affiliated Hospital of Chengdu University.
Li Zhirui, Hainan Hospital of the PLA General Hospital.
Li Weixu, the Second Affiliated Hospital of Zhejiang University School of Medicine.
Liang Jiali, University of Hong Kong, Shenzhen Hospital.
Liao Qi, the Second Affiliated Hospital of Nanchang University.
Lin Fengfei, Fuzhou Second Hospital.
Lin Peng China‐Japan Friendship Hospital.
Lin Gaoyuan, Xiangya Hospital of Central South University.
Liu Fan Nantong University Affiliated Hospital.
Liu Guangyao, Orthopedic Center of China‐Japan Friendship Hospital, Jilin University.
Liu Guohui, Tongji Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology.
Liu Limin, Xuanwu Hospital, Capital Medical University.
Luo Congfeng, Shanghai Sixth People's Hospital.
Lu Decheng, the First Affiliated Hospital of Dalian Medical University.
Lv Gang, Xinjiang Uygur Autonomous Region Hospital of Traditional Chinese Medicine.
Lu Houchen, Orthopedics Department of the Chinese People's Liberation Army General Hospital.
Lv Zhi, the Second Hospital of Shanxi Medical University.
Ma Baotong, Tianjin, Tianjin Hospital.
Ma Xianzhong, Henan Province, Luoyang Bone Setting Hospital.
Ma Xinlong, Tianjin, Tianjin Hospital.
Ni Jiangdong, Second Xiangya Hospital, Central South University.
Ni Weidong, Orthopedics Department of the First Affiliated Hospital of Chongqing Medical University.
Pan Zhijun, the Second Affiliated Hospital, Zhejiang University School of Medicine.
Pei Guoxian, Xijing Hospital, Air Force Military Medical University.
Peng Aqin Third Hospital of Hebei Medical University.
Qi Jian, the First Affiliated Hospital of Sun Yat‐sen University.
Qian Hongbo, the General Hospital of the PLA Eastern Theater Command.
Rui Yongjun, Wuxi Ninth People's Hospital.
Sang Shiguang, Qilu Hospital, Shandong University.
Shang Jian, the First Affiliated Hospital of Harbin Medical University.
Shao Lin, the Second Affiliated Hospital of Harbin Medical University.
Shao Ming, Orthopedics Department of the First Affiliated Hospital of Harbin Medical University.
Shu Hengsheng, Tianjin, Tianjin Hospital.
Sun Dahui, orthopedics department of the First Hospital of Jilin University.
Sun Yuqiang, Shanghai Sixth People's Hospital.
Sun Yuehua, Shanghai Ninth People's Hospital.
Tang Xin, the First Affiliated Hospital of Dalian Medical University.
Tang Jian, Shanghai Ninth People's Hospital.
Tian Yun, Peking University Third Hospital.
Wang Aiguo, Zhengzhou Orthopedic Hospital.
Wang Baojun, Beijing Friendship Hospital, Affiliated to Capital Medical University.
Wang Dong, the Second Hospital of Shanxi Medical University.
Wang Gang, Affiliated Southern Hospital of Southern Medical University.
Wang Guanglin, West China Hospital of Sichuan University.
Wang Lei, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine.
Wang Manyi, Beijing Jishuitan Hospital.
Wang Pengcheng, the Third Hospital of Hebei Medical University.
Wang Qiugen, Shanghai First People's Hospital.
Wang Yue, Sichuan Provincial People's Hospital.
Wen Liangyuan Beijing Hospital.
Wu Dankai, Department of Orthopedics, Second Affiliated Hospital of Jilin University.
Wu Kejian, Orthopedic Medicine Department of the Chinese People's Liberation Army General Hospital.
Wu Xinbao, Beijing Jishuitan Hospital.
Xie Zenggru, First Affiliated Hospital of Xinjiang Medical University.
Xie Zhao, Southwest Hospital, Army and Military Medical University.
Xu Ming, the First Affiliated Hospital of Suzhou Medical University.
Xu Weiguo, Tianjin, Tianjin Hospital.
Xu Yongqing, PLA Joint Logistic Support Force 992 Hospital.
Yang Huaqing, Beijing Rehabilitation Hospital affiliated to Capital Medical University.
Yang Jun, Shengjing Hospital Affiliated to China Medical University.
Yang Minghui, Beijing Jishuitan Hospital.
Yang Shengsong, Beijing Jishuitan Hospital.
Yao Qi, Beijing Shijitan Hospital affiliated to Capital Medical University.
Ye Fagang, the Affiliated Hospital of Qingdao University.
Ye Junjian, the First Affiliated Hospital of Fujian Medical University.
Yu Baoqing, Shanghai Pudong Hospital.
Yuan Zhi, Xijing Orthopedic Hospital of the Air Force and Military Medical University.
Zhang Baozhong, Peking Union Medical College Hospital.
Zhang Dianying, Peking University People's Hospital.
Zhang Jinli, Tianjin, Tianjin Hospital.
Zhang Kun, Xi'an Honghui Hospital.
Zhang Qun, Department of Orthopedic Medicine of the PLA General Hospital.
Zhangshou Haikou City People's Hospital.
Zhang Shuming, the Chinese People's Liberation Army Rocket Force General Hospital.
Zhang Yakui Beijing Luhe Hospital affiliated to Capital Medical University.
Zhang Changqing, Shanghai Sixth People's Hospital.
Zhao Jimin, Guangxi Medical University.
Zhao Wen, Beijing Aerospace General Hospital.
Zhao Zhe, Beijing Tsinghua Changgung Hospital.
Zhenglongpo Shanghai 10th People's Hospital.
Zhou Dongsheng, Department of Orthopedics of Shandong Provincial Hospital.
Zhou Fang, Peking University Third Hospital.
Zhou Junlin, Beijing Chaoyang Hospital affiliated to Capital Medical University.
Zhu Shiwen, Beijing Jishuitan Hospital, trauma and orthopedics department.
Zhu Yong, Xiangya Hospital of Central South University.
Zhuang Yan Xi'an Honghui Hospital Orthopedics.
Zhuang Yunqiang, Ningbo Sixth Hospital.
Zhang Hao, National Clinical Research Center for Orthopedics and Sports Rehabilitation.
Gao Jie, National Clinical Research Center for Orthopedics and Sports Rehabilitation.
Wang Hao, National Clinical Research Center for Orthopedics and Sports Rehabilitation.
Li Qing, National Clinical Research Center of Orthopedics and Sports Rehabilitation.
All authors declare no conflict of interest.
The Special Project Program of the National Clinical Research Center for Orthopedics, Sports Medicine & Rehabilitation (2022‐NCRC‐000000); The Equipment Scientific Research Projects for the Military Equipment (LB20201A050008).
Tiansheng Sun, Email: suntiansheng-@163.com.
Peifu Tang, Email: pftang301@126.com.
Yingze Zhang, Email: dryzzhang@126.com.