Objective To improve the knowledge on dynamic benign central airway stenosis through two typical cases. Methods The clinical features, imaging findings, and bronchial morphologic changes of two cases characterized by dynamic benign central airway stenosis were retrospectively analyzed. The etiologies for the two cases were tracheobronchomalacia (TBM) and excessive dynamic airway collapse (EDAC), respectively. Results Central airway stenosis and reversible airway obstruction were common clinical characteristics for the two cases. However, there were identifiable differences on imaging findings and bronchial morphologic changes between the two cases. Multidetector computed tomography showed sabre-sheath trachea and narrowed trachea in coronal position for TBM, while small sized trachea in exhalation phase and narrowed trachea in sagittal position for EDAC. Bronchoscopy displayed narrowed airway, swelling mucosa, and the absence of annular cartilage for TBM, while crescent airway with membranacea part protruding to lumen in inspiration phase, and the integrity of annular cartilage for EDAC. Conclusion Multidetector computed tomography and bronchoscopy examinations are valid methods to distinguish TBM and EDAC, which are both characterized by dynamic benign central airway stenosis.
ObjectiveTo explore the different imaging manifestations of osteonecrosis of the femoral head (ONFH) and their correlation with the occurrence of pain during the peri-collapse period.MethodsThe 372 patients (624 hips) with ONFH in the peri-collapse stage who were admitted between December 2016 and October 2019 and met the selection criteria were selected as the research objects. Among them, there were 270 males and 102 females, with an average age of 35.3 years (mean, 15-65 years). There were 120 cases of unilateral hip and 252 cases of bilateral hips. There were 39 cases (39 hips) of traumatic ONFH, 196 cases (346 hips) of hormonal ONFH, 102 cases (178 hips) of alcoholic ONFH, and 35 cases (61 hips) of idiopathic ONFH. Among them, there were 482 hips with pain symptoms and 142 hips without pain. The pain duration was less than 3 months in 212 hips, 3-6 months in 124 hips, 6-12 months in 117 hips, and more than 12 months in 29 hips. According to the Association Research Circulation Osseous (ARCO) staging, the ONFH was rated as stage Ⅱ in 325 hips and stage Ⅲ in 299 hips. The patients were grouped according to ONFH etiology and ARCO staging, and hip joint pain and X-ray film (crescent sign and cystic changes), CT (subchondral bone fractures and cystic changes), and MRI (bone marrow edema, joint effusion, and subchondral hypointensity zone) were compared. Spearman rank correlation was used to determine the correlation between ONFH pain duration and X-ray film, CT, and MRI imaging manifestations.ResultsThere were significant differences (P<0.05) between ONFH patients with different etiologies in crescent sign on X-ray film, subchondral bone fracture on CT, and joint effusion on MRI. And there were significant differences (P<0.05) between ONFH patients with different ARCO stages in hip pain duration and all imaging manifestations. Correlation analysis showed that the pain duration of ONFH patients was correlated with all imaging manifestations (P<0.05). The cystic change on CT was correlated with the subchondral hypointensity zone and joint effusion grade on MRI, and subchondral hypointensity zone and joint effusion grade on MRI were also correlated (P<0.05).ConclusionThe cystic changes, subchondral hypointensity zone, and joint effusion are closely related to the collapse of the femoral head and hip pain in patients with ONFH in the peri-collapse stage. The above-mentioned signals in stage Ⅱ ONFH indicate the instability of the femoral head, which is to predict the development of ONFH and the rational choice of hip-preserving treatment methods provides a basis.
Objective To explore the reduction and support effect of the subchondral screw compression technique for residual or secondary collapse of the lateral tibial plateau during operation. Methods Between January 2020 and June 2021, 11 patients with residual or secondary collapse of the lateral tibial plateau during operation were treated with the subchondral screw compression technique. There were 6 males and 5 females, aged 52.3 years old (range, 27-64 years). The fractures were caused by traffic accident in 10 cases and falling from height in 1 case and located at the left knee in 6 cases and the right knee in 5 cases. According to Schatzker classification, there were 5 cases of type Ⅱ fractures, 4 cases of type Ⅲ fractures, and 2 cases of type Ⅴfractures. According to the three columns classification, there were 5 cases of lateral column, 4 cases of lateral column and posterior column, and 2 cases of three columns. The time from injury to operation was 4.5 days (range, 3-7 days). During the follow-up, X-ray films were obtained and the Rasmussen standard was used to evaluate the quality of fracture reduction, meanwhile fracture healing was observed. The medial proximal tibial angle (mPTA), posterior tibial slope angle (pTSA), and articular surface collapse were measured at immediate and 12 months after operation. The knee joint range of motion was evaluated at last follow-up, and the knee joint function was evaluated using the Hospital for Special Surgery (HSS) score. Results All operations were successfully completed, with a mean operation time of 71.4 minutes (range, 55-120 minutes), and a mean hospital stay of 8.0 days (range, 5-13 days). The incisions all healed by first intention, without complications such as infection, flap necrosis, or vascular and nerve injury. All patients were followed up 16.5 months on average (range, 12-24 months). X-ray films showed that the fracture reduction score was 14-18 (mean, 16.7) according to Rasmussen score criteria; and 5 cases were rated as excellent and 6 as good. All fractures healed clinically with a mean clinical healing time of 14.9 weeks (range, 12-16 weeks), and there was no complications such as plate or screw loosening. At 12 months after operation, the mPTA and pTSA were (87.5±1.7)° and (6.2±3.1)°, respectively; there was no significant difference when compared to the values at immediate after operation [(87.6±1.8)° and (6.5±3.1)°] (P>0.05). The articular surface of the tibial plateaus was effectively supported, and it collapsed again by 0-1.0 mm at 12 months, with an average of 0.4 mm. At last follow-up, the knee joint range of motion was 115°-135° (mean, 126.8°) and the HSS score for knee joint function was 87-98 (mean, 93.9). Five patients underwent secondary operation to remove the internal fixator at 12-18 months after operation.ConclusionThe subchondral screw compression technique is helpful for the reduction of residual or secondary collapse of the lateral tibial plateau during operation, and can provide good support for osteochondral blocks.
Circulatory collapse is a common complication of transcatheter aortic valve replacement (TAVR), mainly due to new severe aortic regurgitation after balloon pre-dilation. This article reports the case of an 80-year-old female patient with severe aortic stenosis, who had a type 1 bicuspid aortic valve, with calcified aortic valve commissure between the right and left coronary cusps. During the procedure of TAVR, severe aortic regurgitation was caused by pre-dilation with 20 mm and 23 mm balloons. Then circulatory collapse and cardiogenic shock occurred. After the emergency deployment of the Venus A L26 valve, the cardiovascular hemodynamics was immediately improved. This case suggests that oversized balloon dilation should be avoided to prevent circulatory collapse caused by massive aortic regurgitation.
Objective To investigate the improved reduction technique for depression fractures of the lateral tibial plateau and its effectiveness. Methods Between January 2008 and December 2010, 48 patients (48 knees) with depression fractures of the lateral tibial plateau (Schatzker II or III fractures) were treated. There were 32 males and 16 females with an average age of 45.8 years (range, 16-79 years). All fractures were fresh closed fractures, which were caused by traffic accident in 27 cases, by falling from height in 5 cases, by crushing in 8 cases, and by sustained falls in 8 cases. According to Schatzker classification, 29 cases were classified as type II and 19 cases as type III. The lateral cortex was cut off to expose the depression and compacted cancellous bone was elevated to reset the articular surface. After reduction, autologous iliac bone graft and locking plate internal fixation were used. Results Healing of incision by first intention was achieved in all patients, and no complication occurred. All patients were followed up 1.7 years on average (range, 1-3 years). At last follow-up, the knee extension was ( — 0.5 ± 0.3)°, and the knee flexion was (136.9 ± 8.8)°. X-ray films showed that the fracture healing time was 52 weeks and no breakage of internal fixation occurred. According to Rasmussen clinical score, the results were excellent in 35 cases, good in 10 cases, and fair in 3 cases. According to Rasmussen radiographical score, the results were excellent in 41 cases, good in 7 cases; there were 41 excellent scores and 7 good scores of articular reduction; all gained good recovery of coronal and sagittal alignment and condylar width. The articular surface collapse was (1.0 ± 0.7) mm at immediate postoperatively and (1.2 ± 0.7) mm at last follow-up, showing no significant difference (t= — 1.42, P=0.20), but significant differences were found when compared with that at preoperation [(12.2 ± 8.0) mm, P lt; 0.05]. Conclusion This improved technique can provide a satisfactory effectiveness of fracture reduction and can avoid loss of reduction. The short-term effectiveness is good, but futher follow-up is necessary to determine the long-term results.
Transcatheter aortic valve replacement (TAVR) is a reasonable alternative for patients with severe aortic stenosis who are at a medium or high risk from surgery, and it’s gradually extended to low-risk groups. The safety of surgery is confirmed with the advancement of technology and the improvement of surgical instruments, but surgical complications are still common. Cardiovascular collapse is the leading cause of death during the surgery and not rare. This article reported a case of cardiovascular collapse during TAVR who were successfully rescued, while literature review on the causes and treatment of cardiovascular collapse were made.
Transcatheter aortic valve replacement (TAVR) is the best treatment for severe aortic stenosis with high surgical risk, and low body weight significantly increased the risk of surgery and postoperative all-cause mortality. A case of elderly female diagnosed with severe aortic valve stenosis and extremely low body weight was presented in this article. Additionally, horizocardia and low located coronary orifice were also found in this patient, which markedly increased the risk and complexity of the TAVR procedure. During the operation, circulatory collapse occurred, and prosthetic valve was quickly released under emergency cardiopulmonary resuscitation. The operation was successful and the patient’s vital signs recovered soon. The follow-up showed that the patient was in good condition.
Objective To summarize surgical procedures of hip-preservation based on peri-collapse stage of osteonecrosis of the femoral head (ONFH). Methods The basic points of peri-collapse stage theory was expounded. The related literature on surgical procedures was summarized and analyzed based on the theory. Results Surgical procedures of hip-preservation tend to emphasize on mechanical repair, giving consideration to biological repair. It is consistent with the essence of peri-collapse stage theory, which attaches great importance to biomechanical stability. Conclusion Peri-collapse stage theory has a guiding significance to the choice of surgical timing and approach, and it is one of the important theoretical basis for hip-preservation treatment.
Objective To establish finite element models of different preserved angles of osteonecrosis of the femoral head (ONFH) for the biomechanical analysis, and to provide mechanical evidence for predicting the risk of ONFH collapse with anterior preserved angle (APA) and lateral preserved angle (LPA). Methods A healthy adult was selected as the study object, and the CT data of the left femoral head was acquired and imported into Mimics 21.0 software to reconstruct a complete proximal femur model and construct 3 models of necrotic area with equal volume and different morphology, all models were imported into Solidworks 2022 software to construct 21 finite element models of ONFH with LPA of 45°, 50°, 55°, 60°, 65°, 70°, and 75° when APA was 45°, respectively, and 21 finite element models of ONFH with APA of 45°, 50°, 55°, 60°, 65°, 70°, 75° when LPA was 45°, respectively. According to the physiological load condition of the femoral head, the distal femur was completely fixed, and a force with an angle of 25°, downward direction, and a magnitude of 3.5 times the subject’s body mass was applied to the weight-bearing area of the femoral head surface. The maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head were calculated and observed by Abaqus 2021 software. ResultsThe finite element models of ONFH were basically consistent with biomechanics of ONFH. Under the same loading condition, there was stress concentration around the necrotic area in the 42 ONFH models with different preserved angles composed of 3 necrotic areas with equal volume and different morphology. When APA was 60°, the maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head of the ONFH models with LPA<60° were significantly higher than those of the models with LPA≥60° (P<0.05); there was no significant difference in each index among the ONFH models with LPA≥60° (P>0.05). When LPA was 60°, each index of the ONFH models with APA<60° were significantly higher than those of the models with APA≥60° (P<0.05); there was no significant difference in each index among the ONFH models with APA≥60° (P>0.05). Conclusion From the perspective of biomechanics, when a preserved angle of ONFH is less than its critical value, the stress concentration phenomenon in the femoral head is more pronounced, suggesting that the necrotic femoral head may have a higher risk of collapse in this state.
Objective To explore the effectiveness of limited incision, poking reduction, and simple internal fixation in the treatment of collapsed fractures of the posterolateral tibial plateau. Methods Between October 2010 and January 2016, 16 patients with collapsed fractures of the posterolateral tibial plateau underwent posterolateral incision, poking reduction, and simple internal fixation. There were 10 males and 6 females with the age of 22-63 years (mean, 43.5 years). The injury was caused by falling in 5 cases, traffic accident in 7 cases, and falling from height in 4 cases. All cases had closed fractures. The left knee was involved in 9 cases and the right knee in 7 cases. The injury-to-admission time was 2 hours to 3 days (mean, 10 hours). X-ray films showed that the articular surface collapsing was more than 2 mm. According to Schatzker criteria, 6 cases were rated as type II and 10 cases as type III. Twelve cases had fracture of fibular head. The incision length, operation time, intraoperative blood loss, and incision healing were recorded; fracture healing was observed, and tibial plateau angle and posterior slope angle were measured on X-ray films; loss of articular surface reduction was observed by CT scan; and American Hospital for Special Surgery (HSS) score was used to evaluate the knee joint function. Results The incision length was 7-10 cm (mean, 8.6 cm); operation time was 35-55 minutes (mean, 46 minutes); intraoperative blood loss was 10-35 mL (mean, 28 mL). Primary healing of incision was obtained. Skin pain occurred in 1 case at 2 months because Kirschner wire retracted. Fifteen cases were followed up 8-21 months (mean, 13.5 months). The fracture healing time was from 3 to 6 months (mean, 4.8 months). There was no significant difference in tibial plateau angle and posterior slope angle between at immediate after operation and at last follow-up (t=–1.500, P=0.156; t=–1.781, P=0.097). The anatomic reduction rate of articular surface was 93.8% (15/16) at immediate after operation. At last follow-up, the recollapse height of articular surface was 0.1-1.2 mm (mean, 0.36 mm). According to the HSS score system, the results were excellent in 12 cases, good in 2 cases, and fair in 1 case, and the excellent and good rate was 93.3%. Conclusion The limited incision by posterolateral approach, poking reduction, and simple internal fixation have the advantages of small injury, full exposure, and easy operation in the treatment of simple posterolateral tibial plateau fractures; bone graft support and simple internal fixation can prevent recollapse of the articular surface and achieve satisfactory knee function.