Objective To establ ish a porcine model of articular full-thickness cartilage defect characterized byremaining cartilage calcified zone on femoral trochlea, so as to provide a considerable and comparative control group forinvestigating repair effects of tissue engineered scaffolds in articular cartilage defects with cartilage calcified zone remaining.Methods The full-thickness cartilage column defects (6 mm in diameter, 0.2-0.5 mm in depth) without damage on calcifiedcartilage zone were made on the femoral trochlea in 9 clean-grade 6-month-old Guizhou mini pigs by standard cartilage-defectmakingsuites. Microscopical observation was performed after modeling. Scanning were made by 3.0T MRI at 4 weeks. Thengeneral observation, stereomicroscope, and histological staining were used to observe cartilage repair. Results All animals wereal ive. No infection of incisions or patellar dislocations occurred; they were able to walk with partial weight-bearing immediatelyafter surgery and could move freely without limp at 1 week. Obvious signal discontinuity in trochlea and subchondral bone couldbe observed in MRI, without deep signal change in defects surrounding. Microscopical observation showed a few repair tissueand petechia at base of the defect with clear boundary. Nearly intact calcified zone of cartilage and zonal collapse of subchondralbone in defects could be observed with stereomicroscope. Under common microscope, no chondrocytes was found in defects,as well as negative staining of fast green-safranin O and alcian blue. Under polarized microscope, the bottom of defects werefilled with a l ittle of fibrous tissue presenting continuous and b l ight-refraction by sirius red staining. Conclusion Theanimal model of articular full-thickness cartilage defect on femoral trochlea by standard cartilage-defect-making suites can beapplied for the research of cartilage disease in early human osteoarthritis and function of calcified cartilage zone in pig.
ObjectiveThe antibacterial properties of porous medical implant materials were reviewed to provide guidance for further improvement of new medical implant materials.MethodsThe literature related to the antibacterial properties of porous medical implant materials in recent years was consulted, and the classification, characteristics and applications, and antibacterial methods of porous medical implant materials were reviewed.ResultsPorous medical implant materials can be classified according to surface pore size, preparation process, degree of degradation in vivo, and material source. It is widely used in the medical field due to its good biocompatibility and biomechanical properties. Nevertheless, the antibacterial properties of porous medical implant materials themselves are not obvious, and their antibacterial properties need to be improved through structural modification, overall modification, and coating modification.ConclusionAt present, coating modification as the mainstream modification method for improving the antibacterial properties of porous medical materials is still a research hotspot. The introduction of new antibacterial substances provides a new perspective for the development of new coated porous medical implant materials, so that the porous medical implant materials have a more reliable antibacterial effect while taking into account biocompatibility.
Objective To evaluate the relevance of the macular hole index (MHI) and the visual outcomes of the idiopathic macular hole (IMH) after the retinal internal limiting membrane (ILM） peeling surgery.Methods Thirty IMH patients (30 eyes) undergoing vitrectomy and ILM peeling were included in this study. The IMH diagnosis was confirmed by best corrected visual acuity (BCVA), slit lamp microscope, indirect ophthalmoscope and optical coherence tomography (OCT). The central retinal thickness, the height and the base diameter of macular holes were measured by OCT. The MHI was the ratio of the height and the base diameter of macular holes. The patients were divided into two groups (MHIge;0.5 group and MHI＜0.5 group) according to the MHI.The post-surgery follow-up was three to 24 months with an average of 10 months. Spearman correlation analysis was performed between BCVA (pre and post-surgery), age, disease duration and MHI. The differences in BCVA after surgery between the two MHI groups was further evaluated by independent samplest-test for quantitative data.Results All the macular holes in 30 eyes closed after surgery, closure rate was 100%. Postoperative BCVA was correlated with MHI by Spearman analysis (r=0.852,P＜0.001), but not correlated with age (r=0.001, P=0.804) and disease course (r=-0.001,P=0.579). Postoperative BCVA was better in the MHIge;0.5 group (t=5.552,P＜0.001). Conclusions The postoperative visual outcome of IMH patients was correlated with the MHI. MHI can be used as a prognostic factor of postoperative visual outcomes for IMH patients.
ObjectiveTo investigate the effectiveness of double osteotomy and lengthening of proximal phalanx and metacarpal with Ilizarov technique in treatment of thumb defect. MethodsBetween February 2017 and June 2019, 6 patients with traumatic thumb defects were treated with double osteotomy and lengthening of proximal phalanx and metacarpal by Ilizarov technique. There were 5 males and 1 female. The age ranged from 28 to 57 years, with an average of 41.5 years. There were 3 cases on the left side and 3 cases on the right side. All patients were admitted to the hospital in emergency department after injury, and the stump of the thumb was trimmed and sutured. The osteotomy plane was the distal part of the proximal phalanx in 4 cases and the interphalangeal joint in 2 cases. The interval between injury and osteotomy was 20-245 days (median, 34.5 days). After minimally invasive osteotomy and placement of a semi-circular external fixator, the lengthening began on the 5th day. The proximal phalanx and metacarpal were lengthened by 0.5 mm every day, once every 12 hours. The thumb of the affected side was distracted to the middle of the distal phalanx of the healthy thumb, and the fixator was removed after the bone healed. ResultsThe distraction time was 14-23 days, with an average of 18.8 days. The osteotomies were healed with healing time of 91-147 days (mean, 120.2 days). The total distraction length of the proximal phalanx and metacarpal was 1.40-2.25 cm, with an average of 1.86 cm; healing index was 51.0-72.2 days/cm, with an average of 64.9 days/cm. All patients were followed up 5-12 months (mean, 8.2 months). At last follow-up, the two-point discrimination was 5.3-8.5 mm with an average of 6.98 mm. According to the evaluation standard of the upper limb part of the Chinese Medical Association, the score was 10-14, with an average of 12.5. Among them, 4 cases were excellent and 2 cases were good, with an excellent and good rate of 100%. All patients were satisfied with the function and appearance of thumb after operation. The Quick Disabilities of Arm, Shoulder, and Hand (Quick-DASH) score was 2.3-9.1, with an average of 6.1. ConclusionThe double osteotomy and lengthening of proximal phalanx and metacarpal with Ilizarov technique is an effective method for the treatment of thumb defects.