A new fixator for spine was designed to restore the stability of spine in improving the treatment of thoraco-lumbar dislocation. This instrument was composed of six nails, two longitudinal connecting rods and two transverse connecting rods. On the surface of the nails, there were furrows engraved, instead of screw thread. It fixed the spine through pedicle of vertebra from the posterior approach. The fixed vertebrae were limited between two vertebrae. From 1989 th 1995, twelve patients with fracture-dislocation of thoraco-lumbar spine were reduced with this instrument. After four years follow-up, it showed that the deformity was corrected and the spine firmly fixed. Compared with Dick’s screws, it had the following advantages such as simple manipulation, increased strergth of nails and minimal damage to tissue during operation.
The causes of development of 56 cases of bone defects from firearm injuries of extremities were analyzed, and the advantages of transfer of vascularized iliac bone graft with deep iliac circumflex vessels in 28 cases and the indications of transfer of vascularked fibular bone graft with fibular vessel in 15 cases and the exporiences in 9 cases from the methed of transter of seapula-cutaneous composite graft were summarized. It was emphatically pointed out that the half-circle typo externa fixators had its unique advantages in the treatment of the bone defects of long bones of extremities from firearm injuries. It would enentually become the method of priority for the treatment of fractures, nonunion of fractures and bone defects of extremities from firearm injuries.
Objective To investigate the long-term effectiveness of Ni-Ti memory alloy tripod fixator in the treatment of Kienböck disease. Methods The clinical data of 22 patients with Kienböck disease who were treated with Ni-Ti memory alloy tripod fixator between January 2011 and September 2013 and followed up more than 10 years was retrospectively analyzed. There were 14 males and 8 females with an average age of 45 years (range, 20-64 years). The Lichtman staging was stage Ⅲb. According to AO/Association for the Study of Internal Fixation (AO/ASIF) classification, there were 6 cases of type B1, 2 cases of type B2, 10 cases of type B3, and 4 cases of type C2. The disease duration ranged from 18 to 50 months, with an average of 30.7 months. The operation time, intraoperative blood loss, and complications were recorded. Wrist height ratio and scapholunate angle were measured by wrist anteroposterior and lateral X-ray films before and after operation. The grip strength of bilateral hands was measured by Jamar dynamometer. The wrist pain was evaluated by visual analogue scale (VAS) score, and the wrist function was evaluated by Mayo score, and the radial deviation, ulnar deviation, dorsiflexion, and palmar flexion range of motion of wrist were measured. Results The operation time was 45-60 minutes, with an average of 52.21 minutes; the intraoperative blood loss was 50-60 mL, with an average of 58.63 mL. No nerve or blood vessel injury occurred during operation. All patients were followed up 10-13 years (mean, 11.3 years). X-ray films at 3 months after operation showed that the density of lunate bone was lower than that before operation. Satisfactory fusion of the scapho-trapezio-trapezoeid joint was achieved at 3-6 months after operation (mean, 4.5 months), and the wrist height ratio and the scapholunate angle after fusion significantly improved when compared with those before operation (P<0.05). Wrist pain relieved, scaphoid rotation and dislocation improved, and no radiocarpal joint degeneration was found during follow-up, and no internal fixator loosening, breakage, or lunate bone necrosis occurred. At last follow-up, the wrist radial deviation, ulnar deviation, dorsiflexion, and palmar flexion range of motion, VAS score, and grip strength of the affected side significantly improved when compared with those before operation (P<0.05); the grip strength of the affected side recovered to 99.00%±1.25% of the healthy side. Mayo score ranged from 72 to 93, with an average of 85; 14 cases were rated as excellent, 5 good, and 3 satisfactory, the excellent and good rate was 86.4%. ConclusionIn the treatment of stage Ⅲb Kienböck’s disease, the scapho-trapezio-trapezoeid joint usion using Ni-Ti memory alloy tripod fixator can effectively reduce pain, improve hand function, and prevent further deterioration, and achieve good long-term effectiveness.
Objective To investigate the cl inical appl icabil ity and value of internal fixator for the reconstruction of lumbar isthmus in the treatment of lumbar vertebral spondylolysis and to lay a fundation for its cl inical appl ication. Methods Sixteen healthy goats weighing 22.65-31.22 kg were selected to establ ish the models of vertebral spondylolysis at L5, which thereafter were randomized into two groups (n=8): bone graft group in which 0.8-1.1 g fresh autogenous bone was transplanted into the isthmus spondylolysis area, and internal fixation with bone graft group in which internal fixator was installed before transplanting 0.8-1.1 g fresh autogenous bone into the isthmus spondylolysis area. All animals were killed 8 weeks after operation to receive imaging, topographic anatomy and histology detection. Meanwhile, biomechanics test was performed by using 5 donated vertebral body specimens (4 males and 1 female aged 35-51 years old). The left isthmus of L5 vertebra was transected to serve as lumbar vertebral spondylolysis model. A mini-displacement sensor was put at the transected ends of the isthmus. Then loading was conducted with a constant velocity of 2 mm/min by electronic omnipotent tester simulating the direction of fixation force of the internal fixator, and the deformation value of the transected ends was collected by a dynamic data collector and analyzer. The loading wascontinued until the vertebra specimens were damaged. The deformation of displacement sensor and the closure of transected ends of the lumbar isthmus were observed. Results All the goats behaved normally shortly after operation, and no nerve injury induced by operation and no wound infection occurred. Bilaterally obl ique X-ray films of lumbar vertebra and topographic anatomy 8 weeks after operation showed the fusion rate of the internal fixation and bone graft group and the bone graft group was 100% and 62.5%, respectively, indicating there was a significant difference (P lt; 0.05). Histology observation showed 3 goats in the bone graft group presented empty bone trabecula, empty bone lacuna and the disappearance of osteocytes at the transected ends of lumbar isthmus; while in the internal fixation and bone graft group, the bone trabecula grew into cancellous structures with hematopoietic and fatty bone marrow tissue inside, and parts of the bone trabecula had various degrees of mosaic-l ike pattern. During the upload, the biomechanics test and data processing results showed when the external load was 40 N, the deformation of displacement sensor was identified and the gap between the transected ends of lumbar isthmus started to close; then with the increase of external load, the displacement sensor tended to ascend in a l inearity manner; while when the external load was 212 N, the displacement sensor had no further deformation, the gap between the transected ends of lumbar isthmus wascompletely closed, and the pressor effect appeared. Conclusion The internal fixator for the reconstruction of lumbar isthmus has mechanical effects of stabil izing and elevating pressure with a high fusion rate.
ObjectiveTo summarize the effectiveness of nitinol memory alloy two foot fixator with autologous cancellous bone grafting in treating old scaphoid fracture and nonunion.MethodsBetween January 2013 and January 2017, 11 patients of old scaphoid fracture and nonunion were treated with nitinol memory alloy two foot fixator and autologous cancellous bone grafting. All patients were male with an average age of 26.1 years (range, 18-42 years). The fractures were caused by sport in 3 cases, falling in 7 cases, and a crashing object in 1 case. The interval between injury and operation was 6-18 months (mean, 8.9 months). Postoperative outcome measures included operation time, fracture healing time, grip strength, range of motion (ROM) of flexion, extension, ulnar deviation, and radial deviation, Mayo score, visual analogue scale (VAS) score, and the Disabilities of the Arm, Shoulder, and Hand (DASH) score.ResultsThe operation time was 35-63 minutes (mean, 48 minutes). All incisions had primary healing with no infection and loosening or breakage of internal fixator. All patients were followed up 12-30 months (mean, 20.7 months). X-ray films showed that fracture healing was achieved in all patients with an average time of 15 weeks (range, 12-25 weeks). All internal fixators were removed after 10-12 months of operation (mean, 11.2 months). At last follow-up, the grip strength, ROMs of flexion, ulnar deviation, and radial deviation were superior to those before operation (P<0.05), no significant difference was found in ROM of extension between pre- and post-operation (t=0.229, P=0.824). There were significant differences in above indexes between affected and normal sides (P<0.05). At last follow-up, the Mayo, VAS, DASH scores were also significantly superior to those before operation (P<0.05).ConclusionFor the old scaphoid fracture and nonunion, Ni-Ti arched shape-memory alloy fixator and autologous cancellous bone grafting can obtain good effectiveness, which is an effective treatment.