Stent migration is one of the common complications following transcatheter valve implantation. This study aims to design a "drum-shaped" balloon-expandable aortic valve stent to address this issue and conduct a mechanical analysis. The implantation process of the stent was evaluated using a method that combines numerical simulation and in vitro experiments. Furthermore, the fatigue process of the stent under pulsatile cyclic loading was simulated, and its fatigue performance was assessed using a Goodman diagram. The process of the stent migrating toward the left ventricular side was simulated, and the force-displacement curve of the stent was extracted to evaluate its anti- migration performance. The results showed that all five stent models could be crimped into a 14F sheath and enabled uniform expansion of the native valve leaflets. The stress in each stent was below the ultimate stress, so no fatigue fracture occurred. As the cell height ratio decreased, the contact area fraction between the stent and the aortic root gradually decreased. However, the mean contact force and the maximum anti-migration force first decreased and then increased. Specifically, model S5 had the smallest contact area fraction but the largest mean contact force and maximum anti-migration force, reaching approximately 0.16 MPa and 10.73 N, respectively. The designed stent achieves a "drum-shaped" change after expansion and has good anti-migration performance.
Stents ; Prosthesis Design ; Heart Valve Prosthesis ; Humans ; Aortic Valve/surgery* ; Stress, Mechanical ; Transcatheter Aortic Valve Replacement/instrumentation*

OBJECTIVE: To analyze the short-term effectiveness and safety of personalized three-dimensional (3D) printed customized prostheses in severe Paprosky type Ⅲ acetabular bone defects. METHODS: A retrospective analysis was conducted on 8 patients with severe Paprosky type Ⅲ acetabular bone defects and met the selection criteria between January 2023 and June 2024. There were 3 males and 5 females, with an average age of 64.6 years ranged from 56 to 73 years. All primary replacement prostheses were non-cemented, including 1 ceramic-ceramic interface, 1 ceramic-polyethylene interface, and 6 metal-polyethylene interfaces. The time from the primary replacement to the revision was 4 days to 18 years. The reasons for revision were aseptic loosening in 5 cases, revision after exclusion in 2 cases, and repeated dislocation in 1 case. The preoperative Harris score was 39.5±3.7 and the visual analogue scale (VAS) score was 7.1±0.8. The operation time, intraoperative blood loss, hospital stay, and complications were recorded. The hip function was evaluated by Harris score, and the degree of pain was evaluated by VAS score. The acetabular cup abduction angle, anteversion angle, rotational center height, greater trochanter height, and femoral offset were measured on X-ray film. RESULTS: The operation time was 95-223 minutes, with an average of 151.13 minutes. The intraoperative blood loss was 600-3 500 mL, with an average of 1 250.00 mL. The hospital stay was 13-20 days, with an average of 16.88 days. All 8 patients were followed up 2-12 months, with an average of 6.4 months. One patient had poor wound healing after operation, which healed well after active symptomatic treatment. One patient had lower limb intermuscular vein thrombosis, but no thrombosis was found at last follow-up. No serious complications such as aseptic loosening, infection, dislocation, and periprosthetic fracture occurred during the follow-up. At last follow-up, the Harris score was 72.0±6.2 and the VAS score was 1.8±0.7, which were significantly different from those before operation ( t=-12.011, P<0.001; t=16.595, P<0.001). On the second day after operation, the acetabular cup abduction angle ranged from 40° to 49°, with an average of 44.18°, and the acetabular cup anteversion angle ranged from 19° to 26°, with an average of 21.36°, which were within the "Lewinneck safety zone". There was no significant difference in the rotational center height, greater trochanter height, and femoral offset between the healthy side and the affected side ( P>0.05). CONCLUSION The use of personalized 3D printed customized prostheses for the reconstruction of severe Paprosky type Ⅲ acetabular bone defects can alleviate pain and enhances hip joint function, and have good postoperative prosthesis position, without serious complications and have good safety.
Humans ; Printing, Three-Dimensional ; Male ; Female ; Middle Aged ; Acetabulum/surgery* ; Aged ; Retrospective Studies ; Hip Prosthesis ; Prosthesis Design ; Arthroplasty, Replacement, Hip/instrumentation* ; Reoperation ; Treatment Outcome

OBJECTIVE: To explore the feasibility and effectiveness of suture anchor double-pulley technique combined with suture three-dimensional binding via bone tunnel technique for avulsion fractures of the inferior pole of the patella. METHODS: A clinical data of 38 patients with avulsion fractures of the inferior pole of the patella, who met the selective criteria and were admitted between September 2021 and April 2023, was retrospectively analyzed. The fractures were treated with suture anchor double-pulley technique combined with suture three-dimensional binding via bone tunnel technique in 18 cases (group A) and steel wire tension-band fixation in 20 cases (group B). There was no significant difference in terms of age, gender, cause of fracture, side of fracture, and disease duration between the two groups ( P>0.05). The length of incision, operation time, occurrence of complications, the range of motion of knee joint, and Böstman score of knee joint at last follow-up were recorded. The fracture healing was evaluated through X-ray films and the time of fracture healing was recorded. RESULTS: All incisions healed by first intention. The length of incision was significantly shorter in group A than in group B ( P<0.05). There was no significant difference in the operation time between the two groups ( P>0.05). All patients were followed up 12-24 months (mean, 16.1 months). X-ray films showed that all fractures healed and there was no significant difference in the healing time between the two groups ( P>0.05). At last follow-up, the range of motion and Böstman score of the knee joint in group A were significantly better than those in group B ( P<0.05). During follow-up, 1 patient (5.6%) in group A had one anchor mild prolapse and 3 patients (15.0%) occured internal fixation irritation in group B. But there was no significant difference in the incidence of complications between the two groups ( P>0.05). CONCLUSION For the avulsion fractures of the inferior pole of the patella, the suture anchor double-pulley technique combined with suture three-dimensional binding via bone tunnel technique has advantages of reliable fixation, small incision, avoidance of secondary operation to remove internal fixator, and fewer complications, with definite effectiveness.
Humans ; Male ; Female ; Patella/surgery* ; Suture Anchors ; Fracture Fixation, Internal/instrumentation* ; Adult ; Retrospective Studies ; Middle Aged ; Fractures, Avulsion/surgery* ; Treatment Outcome ; Young Adult ; Range of Motion, Articular ; Fracture Healing ; Adolescent ; Suture Techniques ; Knee Joint/physiopathology*

OBJECTIVE: To explore effectiveness of TiRobot-assisted screw implantation in the treatment of coracoid process fractures of the scapula. METHODS: A retrospective analysis was conducted on the clinical data from 24 patients with coracoid process fractures of the scapula admitted between September 2019 and January 2024 and met selection criteria. Among them, 12 patients underwent TiRobot-assisted screw implantation (robot group) and 12 underwent manual screw implantation (control group) during internal fixation. There was no significant difference ( P>0.05) in baseline data such as gender, age, body mass index, disease duration, cause of injury, coracoid process fracture classification, and proportion of patients with associated injuries between the two groups. The incision length, operation time, intraoperative blood loss, hospital stay, accuracy of screw placement, coracoid process fracture healing time, and complications were recorded and compared, as well as pain visual analogue scale (VAS) score, and Constant-Murley score at last follow-up. RESULTS: The intraoperative blood loss and incision length in the robot group were significantly lower than those in the control group ( P<0.05); however, there was no significant difference in operation time and hospital stay between the two groups ( P>0.05). All patients were followed up 8-27 months (mean, 17.5 months), and the difference in follow-up time between the two groups was not significant ( P>0.05). At last follow-up, the VAS score for shoulder pain in the robot group was signifncatly lower compared to the control group, and the Constant-Murley score was significantly higher ( P<0.05). In the robot group, 16 screws were implanted intraoperatively, while 13 screws were implanted in the control group. Radiographic re-evaluation showed that the excellent and good rate of screw implantation was higher in the robot group (93.8%, 15/16) than in the control group (61.5%, 8/13), but the difference in the precision of screw implantation between the two groups was not significant ( P>0.05). Four patients in the robot group and 1 in the control group achieved double screws fixation; however, the difference in achieving double screws fixation between the two groups was not significant ( P>0.05). All fractures healed in both groups with 1 case of malunion in the control group. There was no significant difference in healing time between the two groups ( P>0.05). During follow-up, 1 patient in the control group experienced screw loosening and displacement. There was no significant difference in the incidence of screw loosening and fracture malunion between the two groups ( P>0.05). CONCLUSION Compared with manual screw implantation, TiRobot-assisted minimally invasive treatment of coracoid process fractures of the scapula can reduce intraoperative blood loss, shorten incision length, alleviate pain, and obtain better promote shoulder joint functional recovery.
Humans ; Male ; Female ; Retrospective Studies ; Fracture Fixation, Internal/instrumentation* ; Minimally Invasive Surgical Procedures/instrumentation* ; Adult ; Middle Aged ; Fractures, Bone/surgery* ; Bone Screws ; Coracoid Process/surgery* ; Robotic Surgical Procedures/methods* ; Scapula/surgery* ; Treatment Outcome ; Operative Time ; Young Adult ; Length of Stay ; Blood Loss, Surgical

OBJECTIVE: To compare the effectiveness of ultrasound-guided closed reduction with Kirschner wire fixation and open reduction with Kirschner wire fixation in the treatment of humeral lateral condyle fracture (HLCF) in children. METHODS: A clinical data of 53 children with HLCF admitted between May 2020 and April 2023 and met selective criteria was retrospectively analyzed. Of these, 25 cases were managed with closed reduction and Kirschner wire fixation under ultrasound guidance (closed group), while 28 cases underwent open reduction and Kirschner wire fixation (open group). There was no significant difference between the two groups in terms of gender, age, cause of injury, fracture side, fracture classification, and time from injury to operation ( P>0.05). The following variables were recorded and compared between the two groups: operation time, intraoperative fluoroscopy frequency, fracture healing time, incidence of complications, and the Flynn elbow function score at last follow-up. RESULTS: In the closed group, the fractures were successfully reduced under ultrasound guidance, with no nerve damage reported in either group. The operation time and intraoperative fluoroscopy frequency were significantly less in the closed group than in the open group ( P<0.05). One case of infection (Kirschner wire irritation) was observed in the closed group, while 3 cases in the open group (2 of Kirschner wire irritation and 1 of incision infection). However, the difference in the incidence of infection between the two groups was not significant ( P>0.05). All patients in both groups were followed up 6-18 months (mean, 10.2 months). X-ray examinations confirmed that fractures had healed in both groups, with no significant difference in healing time ( P>0.05). During follow-up, 5 cases of lateral humeral process formation were observed in the closed group, compared to 12 cases in the open group, although this difference was not significant ( P>0.05). At last follow-up, the excellent and good rate of elbow joint function was evaluated as 96.0% (24/25) in the closed group and 92.9% (26/28) in the open group according to the Flynn scoring criteria, with no significant difference between the two groups ( P>0.05). Both groups showed no occurrence of ossifying myositis or elbow internal/external rotation. CONCLUSION The effectiveness of ultrasound-guided closed reduction and Kirschner wire fixation in the treatment of HLCF in children is comparable to open reduction and Kirschner wire fixation, but the former can reduce operation time and intraoperative fluoroscopy frequency, and obtain lower the incidence of complications.
Humans ; Humeral Fractures/diagnostic imaging* ; Bone Wires ; Male ; Female ; Child ; Retrospective Studies ; Fracture Fixation, Internal/instrumentation* ; Treatment Outcome ; Child, Preschool ; Open Fracture Reduction/methods* ; Fracture Healing ; Elbow Joint/surgery* ; Adolescent ; Closed Fracture Reduction/methods* ; Fluoroscopy ; Operative Time

OBJECTIVE: To discuss the elbow skin fold extension line in Kirschner wire internal fixation of extended supracondylar humeral fractures in children. METHODS: The clinical data of 58 children with extended supracondylar fractures of the humerus who met the selection criteria between August 2021 and July 2024 were retrospectively analyzed. In 28 cases, needle placement of medial epicondyle of humerus was performed with the assistance of the elbow skin fold extension line (study group), and 30 cases were assisted by routine touch of the medial epicondyle of the humerus (control group). There was no significant difference in baseline data such as gender, age, side, cause of injury, Gartland type, Kirschner wire configuration, and time from injury to operation between the two groups ( P>0.05). The closed reduction rate, total operation time, time of medial humeral condyle pin placement, fluoroscopy times during medial pin placement, rate of one-time determination of medial entry point, ulnar nerve injury incidence, and fracture healing time were recorded and compared between the two groups. At the same time, the closed reduction rate of patients with the time from injury to operation ≤24 hours and >24 hours was compared. The elbow function was evaluated by Mayo elbow function score. RESULTS: The closed reduction rate of the study group was significantly higher than that of the control group ( P<0.05). Among all patients, the closed reduction rate of patients with the time from injury to operation ≤24 hours [73.3% (22/30)] was significantly higher than that of patients >24 hours [42.9% (12/28)] ( χ ²=5.545, P=0.019). The total operation time, medial needle placement time, and fluoroscopy times in the study group were significantly less than those in the control group, and the one-time determination rate of medial needle entry point in the study group was significantly higher than that in the control group ( P<0.05). There were 4 cases of ulnar nerve injury in the control group, and no ulnar nerve injury in the study group, but there was no significant difference in the incidence of ulnar nerve injury between the two groups ( P>0.05). All patients were followed up 6-12 months (mean, 8 months). There was no bone nonunion in both groups, and the fracture healing time of the study group was significantly shorter than that of the control group ( P<0.05). Volkmann ischemic contracture, heterotopic ossification, myositis ossificans, and premature epiphyseal closure were not observed after operation. No complications such as loosening or fracture of Kirschner wire occurred. At last follow-up, the Mayo elbow joint function score was used to evaluate function, and there was no significant difference between the two groups ( P>0.05). CONCLUSION In the treatment of extended supracondylar fractures of the humerus in children, the elbow skin fold extension line can help to quickly locate the medial epicondyle of the humerus, quickly insert Kirschner wire, and reduce the operation time and trauma.
Humans ; Humeral Fractures/surgery* ; Bone Wires ; Male ; Female ; Fracture Fixation, Internal/instrumentation* ; Retrospective Studies ; Child ; Elbow Joint/physiopathology* ; Child, Preschool ; Treatment Outcome ; Fracture Healing ; Ulnar Nerve/injuries* ; Adolescent ; Range of Motion, Articular

OBJECTIVE: To analyze the effectiveness of three internal fixation methods, namely hollow screw combined with Kirschner wire tension band, hollow screw combined with anchor nail, and modified 1/3 tubular steel plate, in the treatment of avulsion fracture of tibial tubercle (AFTT) in adolescents. METHODS: Between January 2018 and September 2023, 19 adolescent AFTT patients who met the selection criteria were admitted. According to different internal fixation methods, patients were divided into group A (8 cases, hollow screw combined with Kirschner wire tension band), group B (6 cases, hollow screw combined with anchor nail), and group C (5 cases, modified 1/3 tubular steel plate). There was no significant difference in the baseline data of age, gender, side, cause of injury, Ogden classification, and time from injury to operation among the three groups ( P>0.05). The range of motion (ROM), weight-bearing time, normal activity time of knee joint, and the hospital for special surgery (HSS) score at last follow-up were recorded and compared among the three groups. Recorded whether the fracture was displaced, whether the fracture line was blurred at 1 month after operation, whether there was epiphyseal dysplasia, and whether there was incision infection and other complications. RESULTS: There was no significant difference in hospital stay between the groups ( P>0.05). All patients were followed up 10-24 months, with an average of 14.3 months; there was no significant difference between the groups ( P>0.05). All the incisions healed well without soft tissue irritation or fracture nonunion, and no limb shortening deformity or epiphyseal dysplasia was found during follow-up. At 1 month after operation, the knee joint ROM and hospitalization expenses in group A were better than those in groups B and C, the fracture healing time, knee joint weight-bearing time, and normal activity time of knee joint were better than those in group C, and the hospitalization expenses in group C were better than those in group B, with significant differences ( P<0.05); there was no significant difference in the other indicators between the groups ( P>0.05). In group A, the fracture line was blurred 1 month postoperatively, the fracture ends were in close contact, and there was no fracture displacement; in groups B and C, the fracture line was clear in 2 cases, and 1 case in group C had slight fracture displacement; except for 1 case in group B, there was no fracture split in the other two groups. There was no significant difference in the incidences of blur of fracture line, fracture displacement, and intraoperative bone split between the groups at 1 month after operation ( P>0.05). At last follow-up, the HSS scores of knee joints in the three groups were excellent and good, and there was no significant difference between the groups ( P>0.05). CONCLUSION Hollow screw combined with Kirschner wire tension band technique is effective in treating adolescent AFTT, which has the advantages of stabilizing fracture, accelerating fracture healing and rehabilitation, early feasible knee joint functional exercise, and reducing hospitalization expenses.
Humans ; Tibial Fractures/surgery* ; Adolescent ; Male ; Fracture Fixation, Internal/instrumentation* ; Female ; Fractures, Avulsion/surgery* ; Bone Wires ; Bone Screws ; Bone Plates ; Treatment Outcome ; Range of Motion, Articular ; Bone Nails ; Weight-Bearing ; Fracture Healing

OBJECTIVE: To explore the advantages and effectiveness of the independently developed intelligent orthopedic robot-assisted distal locking of femoral intramedullary nails. METHODS: Thirty-two adult cadaveric femur specimens were randomly divided into two groups, with 16 specimens in each group. The experimental group used the intelligent orthopedic robot to assist in the distal locking of femoral intramedullary nail holes, while the control group used the traditional method of manual locking under X-ray fluoroscopy. The locking time, fluoroscopy times, and the success rate of first locking were recorded and compared between the two groups. RESULTS: The locking time of the experimental group was (273.94±38.67) seconds, which was shorter than that of the control group [(378.38±152.72) seconds], and number of fluoroscopies was (4.56±0.81) times, which was less than that of the control group [(8.00±3.98) times]. The differences were significant [ MD=73.054 (-37.187, 85.813), P=0.049; MD=1.969 (-1.437, 2.563), P=0.002]. The first locking success rate of the experimental group was 100% (16/16), which was significantly higher than that of the control group (68.75%, 11/16) ( P=0.043). CONCLUSION The efficiency of distal locking of femoral intramedullary nails assisted by the intelligent orthopedic robot is significantly higher than that of the traditional manual locking method under fluoroscopy, as it can markedly reduce the time required for distal locking of femoral intramedullary nails, decrease intraoperative radiation exposure, and increase the success rate of locking.
Humans ; Fracture Fixation, Intramedullary/instrumentation* ; Bone Nails ; Fluoroscopy ; Femur/diagnostic imaging* ; Femoral Fractures/surgery* ; Robotic Surgical Procedures/instrumentation* ; Cadaver ; Adult ; Robotics ; Male

OBJECTIVE: To investigate the effectiveness of posterior minimally invasive approach in the treatment of posterior wall acetabular fractures. METHODS: The clinical data of 17 patients with posterior wall acetabular fractures treated with posterior minimally invasive approach between March 2019 and June 2023 were retrospectively analyzed. There were 14 males and 3 females with an average age of 41 years ranging from 28 to 57 years. The causes of injury were traffic accident in 12 cases and falling from height in 5 cases. There were 3 cases complicated with posterior hip dislocation and 2 cases complicated with sciatic nerve injury. According to AO/Orthopaedic Trauma Association (AO/OTA) classification, there were 11 cases of type A1.1 and 6 cases of type A1.2. The time from injury to operation was 5-8 days, with an average of 6.2 days. The incision length, intraoperative blood loss, and operation time were recorded. The quality of posterior wall fracture reduction were evaluated by Matta criteria, and hip function were evaluated by modified Merle d'Aubign-Postel score criteria at 6 months after operation and last follow-up. RESULTS: The operation was successfully completed in 17 cases. The length of incision ranged from 7 to 9 cm, with an average of 8.3 cm, and all incisions healed by first intention. The intraoperative blood loss ranged from 200 to 350 mL, with an average of 281 mL. The operation time ranged from 45 to 70 minutes, with an average of 57 minutes. Two patients had sciatic nerve injury before operation, and the sciatic nerve function recovered completely at 3 months after operation; the other 15 patients had no symptoms of sciatic nerve injury after operation. All the 17 patients were followed up 14-27 months, with an average of 19.5 months. At 1 week after operation, according to the Matta criteria, anatomical reduction was achieved in 12 cases and satisfactory reduction in 5 cases, with a satisfaction rate of 100%. According to the modified Merle d'Aubign-Postel scoring system, the hip function score was 13-18 (mean, 16.1) at 6 months after operation. Among them, 5 cases were excellent, 9 were good, and 3 were fair, with an excellent and good rate of 82.4%. At last follow-up, the hip function score was 7-18 (mean, 13.7), of which 3 cases were excellent, 9 were good, 3 were fair, and 2 were poor, with an excellent and good rate of 70.6%. During the follow-up, there was no infection, failure of internal fixation, and femoral head necrosis, and heterotopic ossification occurred in 2 cases. CONCLUSION The posterior minimally invasive approach has the advantages of less trauma, shorter operation time, less blood loss, without cutting off the external rotator muscle. Exposure through the gluteus medius-piriformis space and piriformis-supercilium space can provide sufficient safe exposure for the posterior wall acetabulum fracture, which is a reliable alternative approach for the posterior acetabular fracture.
Humans ; Acetabulum/surgery* ; Male ; Female ; Adult ; Middle Aged ; Minimally Invasive Surgical Procedures/methods* ; Retrospective Studies ; Fracture Fixation, Internal/instrumentation* ; Fractures, Bone/diagnostic imaging* ; Treatment Outcome ; Operative Time

OBJECTIVE: To investigate the effectiveness of nickel-titanium shape memory staples in treating multiple metatarsal fractures. METHODS: The clinical data of 27 patients with multiple metatarsal fractures who were treated between January 2022 and June 2023 and met the selection criteria were retrospectively analysed. The cohort consisted of 16 males and 11 females, aged 33-65 years (mean, 47.44 years). The causes of injury included heavy object impact in 11 cases, traffic accidents in 9 cases, and crush in 7 cases. Simultaneous fractures of 2, 3, 4, and 5 bones occurred in 6, 6, 4, and 8 cases, respectively, with tarsometatarsal joint injury in 3 cases. Fixation was performed using staples for 16, 22, and 9 fractures in the metatarsal neck, shaft, and the base, respectively, and 5 tarsometatarsal joint injuries. Preoperative soft tissue injuries were identified in 8 cases and classified according to the Tscherne-Oestern closed soft tissue injury classification as type Ⅰ in 5 cases and type Ⅱ in 3 cases. One case of type Ⅱexhibited preoperative skin necrosis. The patients were treated with fixation using nickel-titanium shape memory staples. Complications and fracture healing were documented. At last follow-up, the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score was used to evaluate the function, and the visual analogue scale (VAS) score was used to evaluate the pain. RESULTS: The 27 patients were followed up 9-19 months (mean, 12.4 months). Postoperative X-ray films revealed no loss of fracture reduction, and all fractures achieved bony union. No internal fixator loosening, breakage, or other mechanical failures was observed. The mean fracture healing time was 3.13 months (range, 3-4 months). Postoperatively, 4 cases (2 of Tscherne-Oestern type Ⅰ, 2 of type Ⅱ) developed superficial skin necrosis, which resolved with dressing changes. No infection was observed in the remaining patients, and all wounds healed. At last follow-up, the AOFAS forefoot score ranged from 70 to 95, with an average of 86.6, of which 19 cases were excellent, 6 cases were good, and 2 cases were fair, with an excellent and good rate of 92.6%; the VAS score ranged from 0 to 3, with an average of 0.9, of which 24 cases were excellent, and 3 cases were good, with an excellent and good rate of 100%. CONCLUSION The use of nickel-titanium shape memory staples in the treatment of multiple metatarsal fractures can effectively protect local skin and soft tissues and minimize secondary damage associated with internal fixator insertion. It is a viable surgical option for management of multiple metatarsal fractures.
Humans ; Male ; Female ; Middle Aged ; Adult ; Titanium ; Nickel ; Retrospective Studies ; Fracture Fixation, Internal/instrumentation* ; Aged ; Metatarsal Bones/surgery* ; Fractures, Bone/surgery* ; Treatment Outcome ; Sutures ; Fractures, Multiple/surgery*