Objective To compare the biomechanical properties of personalized Y-shaped plates with horizontal plates, vertical plates, and traditional Y-shaped plates in the treatment of distal humeral intra-articular fractures through finite element analysis, and to evaluate their potential for clinical application. Methods The study selected a 38-year-old male volunteer and obtained a three-dimensional model of the humerus by scanning his upper limbs using a 64-slice spiral CT. Four types of fracture-internal fixation models were constructed using Mimics 19.0, Geomagic Wrap 2017, Creo 6.0, and other software: horizontal plates, vertical plates, traditional Y-shaped plate, and personalized Y-shaped plate. The models were then meshed using Hypermesh 14.0 software, and material properties and boundary conditions were defined in Abaqus 6.14 software. AnyBody 7.3 software was used to simulate elbow flexion and extension movements, calculate muscle strength, joint forces, and load torques, and compare the peak stress and maximum displacement of the four fixation methods at different motion angles (10°, 30°, 50°, 70°, 90°, 110°, 130°, 150°) during elbow flexion and extension. Results Under dynamic loading during elbow flexion and extension, the personalized Y-shaped plate exhibits significant biomechanical advantages. During elbow flexion, the peak internal fixation stress of the personalized Y-shaped plate was (28.8±0.9) MPa, which was significantly lower than that of the horizontal plates, vertical plates, and traditional Y-shaped plate (P<0.05). During elbow extension, the peak internal fixation stress of the personalized Y-shaped plate was (18.1±1.6) MPa, which was lower than those of the other three models, with significant differences when compared with horizontal plates and vertical plates (P<0.05). Regarding the peak humeral stress, the personalized Y-shaped plate model showed mean values of (10.9±0.8) and (13.1±1.4) MPa during elbow flexion and extension, respectively, which were significantly lower than those of the other three models (P<0.05). Displacement analysis showed that the maximum displacement of the humerus with the personalized Y-shaped plate during elbow flexion was (2.03±0.08) mm, slightly higher than that of the horizontal plates, but significantly lower than that of the vertical plates, showing significant differences (P<0.05). During elbow extension, the maximum displacement of the humerus with the personalized Y-shaped plate was (1.93±0.13) mm, which was lower than that of the other three models, with significant differences when compared with vertical plates and traditional Y-shaped plates (P<0.05). Stress contour analysis showed that the stress of the personalized Y-shaped plate was primarily concentrated at the bifurcation of the Y-shaped structure. Displacement contour analysis showed that the personalized Y-shaped plate effectively controlled the displacement of the distal humerus during both flexion and extension, demonstrating excellent stability. ConclusionThe personalized Y-shaped plate demonstrates excellent biomechanical performance in the treatment of distal humeral intra-articular fractures, with lower stress and displacement, providing more stable fixation effects.
To investigate the method and cl inical effect of double-plating fixation in treatment of distal humerus fractures. Methods From April 2003 to January 2009, 21 patients with distal humerus fracture were treated with l imited contact compression plate and reconstruction plate via posterior elbow incision and approach inside and outside the edge of both sides of the triceps. There were 12 males and 9 females, aged from 20 to 63 years (39 years on average). The causes of injury were fall ing in 13 cases, traffic accident in 6 cases, and fall ing from height in 2 cases. According to the classification of Association for the Study of Internal Fixation (AO/ASIF), 8 cases were classified as type 12-B1, 2 as type 12-B2, 7 as type12-B3, 3 as type 13-A2, and 1 as type 13-A3. The course of disease averaged 4.8 days. Results Secretion was observed at incision in 1 case 2 weeks after operation, and incision healed after dressing change; other incisions healed by first intention. Transient numbness of ring and l ittle fingers occurred in 2 cases 2 days after operation; no iatrogenic nerve paralysis occurred. All patients were followed up 13 to 18 months (15 months on average). The X-ray films showed bone healed 6 months after operation. No postoperative joint adhesion occurred, and the motion of elbow joint ranged from 0° to 135°. According to Morrey evaluation standard, the results were excellent in 17 cases, good in 2 cases, and fair in 2 case; the excellent and good rate was 90.5%. Conclusion Double-plating fixation has the advantages of wide indications, rigid internal fixation, and significant curative effects in treatment of distal humerus fractures.
ObjectiveTo investigate the effectiveness of limited internal fixation combined with hinged super-articular external fixator to treat type C3 fracture of the distal humerus. MethodsBetween September 2007 and November 2012, 37 cases of type C3 fracture of the distal humerus were treated. There were 22 males and 15 females with an average age of 43.6 years (range, 22-66 years). The causes were accident injury in 24 cases, falling injury in 5 cases, falling from height in 4 cases, heavy crush injury in 2 cases, machine injury in 1 case, and other injury in 1 case. There were 22 cases of open injury and 15 cases of closed injury. The time from injury to operation was 3-46 hours (mean, 18 hours). ResultsNeedle tract reaction and incision infection occurred in 3 cases and 1 case respectively, healing of incision by first intension was obtained in the other cases. Thirty-six patients were followed up 9-48 months (mean, 25.4 months). Heterotopic ossification occurred in 3 cases after operation and no recurrence was found by release after fracture healing. Fractures healed in the other patients after 6-14 months (mean, 9 months) of operation except 1 patient who suffered chronic osteomyelitis. One patient had delayed ulnar neuritis at 12 months after operation, and the nerve function returned to normal after the ulnar nerve transposition. There was no bone ischemic necrosis, elbow joint instability, or loosening of internal fixation. At last follow-up, the average range of motion of injured elbow was 105.0° in flexion,-25.0° in extension, 69.2° in pronation, and 75.6° in supination. According to Mayo elbow joint function score (MEPS) and disability of arm shoulder and hand (DASH) score, the results were excellent in 22 cases, good in 8 cases, fair in 4 cases, and poor in 2 cases with an excellent and good rate of 83.3%; and according to Cassebaum elbow joint function score, the results were excellent in 21 cases, good in 7 cases, fair in 5 cases, and poor in 3 cases with an excellent and good rate of 77.8%. ConclusionA combination of limited internal fixation and hinged super-articular external fixator has satisfactory clinical curative effect for type C3 fractures of the distal humerus, relatively few complications.
Objective To evaluate the effectiveness of the AO anatomical locking compression plate in treating type C distal humeral fracture. Methods Between July 2008 and April 2009, 13 cases of type C distal humeral fracture were treated with the AO anatomical locking compression plates. There were 5 males and 8 females with an average age of 52.1 years (range, 24-80 years). Fractures were caused by tumbl ing in 7 cases, by traffic accident in 4 cases, and by fall ing from height in2 cases. According to Association for Osteosynthesis/Orthopaedic Trauma Association (AO/OTA) classification, there were 3 cases of type C1, 6 cases of type C2, and 4 cases of type C3. Two cases compl icated by ulnar nerve injuries, 1 by radial nerve injury, 2 by fractures of ulnar olecranon, 3 by fractures of other parts of extremities, and 6 by osteoporosis. The time from injury to hospital ization ranged from 3 hours to 4 days (0.9 day on average). Results All the incisions achieved heal ing by first intention. Thirteen cases were followed up 12 to 21 months with an average of 15.9 months. According to the X-ray films, unions were achieved both at fracture site and the olecranon osteotomy site with a heal ing time of 8 to 13 weeks (10 weeks on average). The function of elbows recovered from 3 to 32 weeks (10 weeks on average). No fixation failure, myositis ossifican, delayed union, or malunion occurred during the follow-up. The Mayo Elbow Performance score ranged from 75 to 100 with an average score of 95.8; the results were excellent in 9 cases, good in 3 cases, and fair in 1 case with an excellent and good rate of 92.3%. Conclusion The AO anatomical locking compression plate has a good fixation in treating type C distal humeral fracture. Through the approach of olecranon osteotomy, it is easy to get anatomical reduction, stable fixation, and early exercise.
ObjectiveTo analyze the effectiveness of external fixator combined with Kirschner wire (EF-KW) fixation in the treatment of oblique and comminuted distal humeral metaphyseal-diaphyseal junction (DHMDJ) fractures in children. Methods A clinical data of 22 children with DHMDJ fractures who met the selection criteria between April 2021 and December 2023 was retrospectively analyzed. All patients were treated with EF-KW fixation. There were 14 boys and 8 girls with an average age of 6.8 years (range, 1.5-12.0 years). The time from injury to operation was 14-38 hours (mean, 24.2 hours). There were 18 cases of comminuted fractures and 4 cases of oblique fractures; and 1 case of median nerve injury and 1 case of radial nerve injury before operation. The occurrence of postoperative complications was recorded. At last follow-up, the function of the affected elbow joint was evaluated according to the Mayo elbow joint function score, and the Baumann’s angle (BA) and humero-capitellar angle (HCA) of the affected and healthy sides were recorded and compared. ResultsAll fractures were successfully treated with closed reduction and no complications such as nerve injury occurred. Superficial infection occurred in 4 cases after operation and healed after symptomatic treatment. The incisions of other patients healed by first intention. All patients were followed up 9-24 months (mean, 13.8 months). At last follow-up, according to the Mayo elbow joint function score, the elbow joint function was rated as excellent in 15 cases, good in 6 cases, and fair in 1 case, with an excellent and good rate of 95.5%. The neurologic injury before operation recovered gradually. X-ray films reexamination showed that all fractures healed, and the healing time of fractures ranged from 29 to 61 days, with an average of 35.6 days. At last follow-up, there was no significant difference in BA and HCA between the healthy side and the affected side (P>0.05). During follow-up, 1 case developed mild cubitus varus, while the other patients had no serious complications. ConclusionEF-KW fixation for oblique and comminuted DHMDJ fractures in children has the advantages of less trauma, simple operation, easy reduction, good stability after reduction, low incidence of serious complications, and good elbow functional recovery.
ObjectiveTo explore the application of three-dimensional (3D) printing technology in precise and individualized surgical treatment of severe distal humeral bone defect.MethodsFive patients with severe distal humeral bone defects were treated with customized 3D printing prostheses between December 2010 and December 2015. There were 4 males and 1 female, with an age of 23-57 years (mean, 35 years); and the length of the bone defect was 5-12 cm (mean, 8 cm). The cause of injury was mechanical injury in 2 cases and strangulation in 3 cases. All of them were the open fracture of Gustilo type Ⅲ. There were 2 cases of radial fracture, 1 case of cubital nerve injury, and 3 cases of radial nerve injury. The time from injury to one-stage operation was 6-18 hours (mean, 10 hours). The operation time, intraoperative blood loss, and intraoperative fluoroscopy were recorded. During follow-up, the anteroposterior and lateral X-ray films of the elbow joints were performed to identify whether there was prosthesis loosening; Mayo Elbow Performance Score (MEPS) and upper extremity Enneking score were used to evaluate limb function.ResultsThe operation time was 140-190 minutes (mean, 165 minutes). The intraoperative blood loss was 310-490 mL (mean, 415 mL). The intraoperative fluoroscopy was 1-3 times (mean, 1.6 times). Five patients were followed up 14-38 months (mean, 21 months). The wound exudate occurred in 1 case and cured after anti-inflammatory local dressing change; the subcutaneous hematoma occurred in 1 case, and improved after color Doppler ultrasound guided puncture and drainage. The MEPS scores and the Enneking scores were all significantly improved when compared with preoperative ones (P<0.05). Except MEPS score between 6 and 12 months after operation had no significant difference (P>0.05), there were significant differences in MEPS scores and Enneking scores between the other time points (P<0.05). During the follow-up, no prosthetic loosening or joint dislocation occurred.Conclusion3D printing technology can achieve personalized treatment of severe distal humeral bone defects, obtain relatively good elbow joint function, and has less postoperative complications and satisfactory effectiveness.