Objective To explore the effectiveness of computer-aided technology in the treatment of primary elbow osteoarthritis combined with stiffness under arthroscopy. Methods The clinical data of 32 patients with primary elbow osteoarthritis combined with stiffness between June 2018 and December 2020 were retrospectively analyzed. There were 22 males and 10 females with an average age of 53.4 years (range, 31-71 years). X-ray film and three-dimensional CT examinations showed osteophytes of varying degrees in the elbow joint. Loose bodies existed in 16 cases, and there were 7 cases combined with ulnar nerve entrapment syndrome. The median symptom duration was 2.5 years (range, 3 months to 22.5 years). The location of bone impingement from 0° extension to 140° flexion of the elbow joint was simulated by computer-aided technology before operation and a three-dimensional printed model was used to visualize the amount and scope of impinging osteophytes removal from the anterior and posterior elbow joint to accurately guide the operation. Meanwhile, the effect of elbow joint release and impinging osteophytes removal was examined visually under arthroscopy. The visual analogue scale (VAS) score, Mayo elbow performance score (MEPS), and elbow range of motion (extension, flexion, extension and flexion) were compared between before and after operation to evaluate elbow function. Results The mean operation time was 108 minutes (range, 50-160 minutes). All 32 patients were followed up 9-18 months with an average of 12.5 months. There was no other complication such as infection, nervous system injury, joint cavity effusion, and heterotopic ossification, except 2 cases with postoperative joint contracture at 3 weeks after operation due to the failure to persist in regular functional exercises. Loose bodies of elbow and impinging osteophytes were removed completely for all patients, and functional recovery was satisfactory. At last follow-up, VAS score, MEPS score, extension, flexion, flexion and extension range of motion significantly improved when compared with preoperative ones (P<0.05). Conclusion Arthroscopic treatment of primary elbow osteoarthritis combined with stiffness using computer-aided technology can significantly reduce pain, achieve satisfactory functional recovery and reliable effectiveness.
ObjectiveTo explore a method of three-dimensional (3D) printing technology for preparation of personalized rat brain tissue cavity scaffolds so as to lay the foundation for the repair of traumatic brain injury (TBI) with tissue engineered customized cavity scaffolds. MethodsFive male Sprague Dawley rats[weighing (300±10) g] were induced to TBI models by electric controlled cortical impactor. Mimics software was used to reconstruct the surface profile of the damaged cavity based on the MRI data, computer aided design to construct the internal structure. Then collagen-chitosan composite was prepared for 3D bioprinter of bionic brain cavity scaffold. ResultsMRI scans showed the changes of brain tissue injury in the injured side, and the position of the cavity was limited to the right side of the rat brain cortex. The 3D model of personalized cavity containing the internal structure was successfully constructed, and cavity scaffolds were prepared by 3D printing technology. The external contour of cavity scaffolds was similar to that of the injured zone in the rat TBI; the inner positive crossing structure arranged in order, and the pore connectivity was good. ConclusionCombined with 3D reconstruction based on MRI data, the appearance of cavity scaffolds by 3D printing technology is similar to that of injured cavity of rat brain tissue, and internal positive cross structure can simulate the topological structure of the extracellular matrix, and printing materials are collagen-chitosan complexes having good biocompatibility, so it will provide a new method for customized cavity scaffolds to repair brain tissue cavity after TBI.
ObjectiveTo investigate the effectiveness of digital three-dimensional (3D) printing osteotomy guide plate assisted total knee arthroplasty (TKA) in treatment of knee osteoarthritis (KOA) patients with femoral internal implants. Methods The clinical data of 55 KOA patients who met the selection criteria between July 2021 and October 2023 were retrospectively analyzed. Among them, 26 cases combined with femoral implants were treated with digital 3D printing osteotomy guide plate assisted TKA (guide plate group), and 29 cases were treated with conventional TKA (control group). There was no significant difference in gender, age, body mass index, side, Kellgren-Lawrence classification, preoperative visual analogue scale (VAS) score, Hospital for Special Surgery (HSS) knee score, knee range of motion, and other baseline data between the two groups (P>0.05). The operation time, intraoperative blood loss, incision length, postoperative first ambulation time, surgical complications; VAS score, knee HSS score, knee range of motion before operation, at 1 week and 3 months after operation, and at last follow-up; distal femoral lateral angle, proximal tibial medial angle, hip-knee-ankle angle and other imaging indicators at last follow-up were recorded and compared between the two groups. ResultsThe operation time, incision length, intraoperative blood loss, and postoperative first ambulation time in the guide plate group were significantly lower than those in the control group (P<0.05). In the control group, there were 1 case of incision rupture and bleeding and 1 case of lower limb intermuscular venous thrombosis, which was cured after symptomatic treatment. There was no complication such as neurovascular injury, incision infection, or knee prosthesis loosening in both groups. Patients in both groups were followed up 12-26 months, with an average of 16.25 months. The VAS score, HSS score, and knee range of motion improved at each time point after operation in both groups, and further improved with time after operation, the differences were significant (P<0.05). The above indicators in the guide plate group were significantly better than those in the control group at 1 week and 3 months after operation (P<0.05), and there was no significant difference between the two groups at last follow-up (P>0.05). At last follow-up, the distal femoral lateral angle, the proximal tibial medial angle, and the hip-knee-ankle angle in the guide plate group were significantly better than those in the control group (P<0.05). Conclusion The application of digital 3D printing osteotomy guide plate assisted TKA in the treatment of KOA patients with femoral implants can simplify the surgical procedures, overcome limitations of conventional osteotomy guides, reduce surgical trauma, achieve individualized and precise osteotomy, and effectively restore lower limb alignment and knee joint function.
ObjectiveTo review the current progress of three-dimensional (3-D) printing technique in the clinical practice, its limitations and prospects. MethodsThe recent publications associated with the clinical application of 3-D printing technique in the field of surgery, especially in orthopaedics were extensively reviewed. ResultsCurrently, 3-D printing technique has been applied in orthopaedic surgery to aid diagnosis, make operative plans, and produce personalized prosthesis or implants. Conclusion3-D printing technique is a promising technique in clinical application.
Objective To investigate the effectiveness of sacroiliac screw implantation assisted by three-dimensional (3D) printed faceted honeycomb guide plate in the treatment of posterior pelvic ring fracture. Methods The clinical data of 40 patients with posterior pelvic ring fractures treated with sacroiliac screw implantation between December 2019 and December 2022 were retrospectively analyzed. Among them, 18 cases were treated with sacroiliac screws fixation assisted by 3D printed faceted honeycomb guide plate (guide plate group), and 22 cases were treated with sacroiliac screws percutaneously fixation under fluoroscopy (conventional group). There was no significant difference in baseline data (P>0.05) such as gender, age, time from injury to operation, and Dennis classification between the two groups. The implantation time, frequency of C-arm X-ray fluoroscopy, frequency of guide pin adjustment of each sacroiliac screw, and postoperative complications and bone healing were recorded. Majeed score was used to evaluate the functional recovery at 6 months after operation, and CT was used to observe whether the screw penetrated the bone cortex. The deviation between the virtual position and the actual position of the screw tip, the sacral foramen, and the screw entry point was measured on the sagittal CT images of the guide plate group. Results The number of screws implanted in S1 and S2 vertebral bodies was 14 and 16 respectively in the guide plate group, and 17 and 18 respectively in the conventional group. The implantation time of each sacroiliac screw, the frequency of C-arm X-ray fluoroscopy, and the frequency of guide pin adjustment in S1, S2, and all vertebrae in the guide plate group were significantly less than those in the conventional group (P<0.05). Patients in both groups were followed up 8-48 months, with an average of 19.7 months. There was no incision infection, screw displacement, or internal fixation loosening in both groups. Callus growth was observed in all patients at 12 weeks after operation, and bone healing was achieved in all patients. The healing time ranged from 12 to 24 weeks, with an average of 15.7 weeks. No sacroiliac screw penetrated the bone cortex in the guide plate group; 2 patients in the conventional group had sacroiliac screws penetrating the bone cortex without damaging blood vessels or nerves. In the guide plate group, the deviation between the virtual position and the actual position of the screw tip, the sacral foramen, and the screw entry point were (2.91±1.01), (2.10±0.74), and (1.67±0.70) mm, respectively, with an average deviation of (2.19±1.22) mm. There was no significant difference in Majeed function evaluation between the two groups at 6 months after operation (P>0.05). Conclusion The application of 3D printed faceted honeycomb guide plate in sacroiliac screw implantation for posterior pelvic ring fracture can shorten the screw implantation time, reduce the frequency of fluoroscopy and guide pin adjustment, and reduce the risk of screw penetration through the bone cortex.
ObjectiveTo investigate the feasibility and early effectiveness to treat osteonecrosis of the femoral head (ONFH) with pedicled iliac bone graft assisted by individual digital design and three dimensional (3D) printed navigation templates. MethodsBetween February and June 2014, 15 patients (24 hips) with ONFH underwent pedicled iliac bone graft assisted by individual digital design and 3D printed navigation templates. There were 11 males (17 hips) and 4 females (7 hips) with a mean age of 38 years (range, 18-56 years) and a mean disease duration of 7.5 months (range, 1-24 months); the left hip was involved in 2 cases, the right hip in 4 cases, and both hips in 9 cases. There were 7 cases (12 hips) of steroid-induced ONFH, 5 cases (8 hips) of alcohol-induced ONFH, 1 case (1 hip) of traumatic ONFH, and 2 cases (3 hips) of idiopathic ONFH. The preoperative Harris score was 56.60±6.97. According to Association Research Circulation Osseous (ARCO) staging system, 5 hips were classified as stage IIB, 8 hips as stage IIC, 6 hips as stage IIIB, and 5 hips as stage IIIC. The navigation templates were designed and printed to assist accurate location and debridement of necrosis area according to preoperative CT scanning at the beginning of pedicled iliac bone grafting procedure. ResultsThe mean operation time was 135 minutes (range, 120-160 minutes), mean amount of bleeding was 255 mL (range, 200-300 mL). All the wounds healed primarily, no complication of deep vein thrombosis or infection was observed. All patients were followed up 12-16 months (mean, 14 months). The location of necrosis area was in accordance with preoperative design, which was removed completely without penetration of joint surface, pedicled iliac bone graft was performed at the right site according to postoperative imaging examination. Radiographically, graft fusion was achieved at 2.7 months (range, 2-3 months) in all patients. All the hips had no collapse during follow-up. Hip pain was relieved, and range of motion was improved. The Harris score was significantly improved to 89.53±5.83 at last follow-up (t=14.319, P=0.000). The results were excellent in 12 hips, good in 10 hips, and fair in 2 hips according to Harris score standard. ConclusionPedicled iliac bone graft assisted by individual digital design and 3D printed navigation templates for treatment of adult ONFH has the advantages of accurate location and complete debridement of necrosis area, so satisfactory results can be obtained.
Shear thinning is an ideal feature of bioink because it can reduce the chance of blocking. For extrusion based biological printing, bioink will experience shear force when passing through the biological printer. The shear rate will increase with the increase of extrusion rate, and the apparent viscosity of shear-thinning bioink will decrease, which makes it easier to block, thus achieving the structural fidelity of 3D printing tissue. The manufacturing of complex functional structures in tissue trachea requires the precise placement and coagulation of bioink layer by layer, and the shear-thinning bioink may well meet this requirement. This review focuses on the importance of mechanical properties, classification and preparation methods of shear-thinning bioink, and lists its current application status in 3D printing tissue trachea to discuss the more possibilities and prospects of this biological material in tissue trachea.
ObjectiveTo fabricate the bionic scaffolds of rat spinal cord by combining three dimensional (3D) printer and 3D software, so as to lay the foundation of theory and technology for the manufacture of scaffolds by using biomaterials. MethodsThree female Sprague Dawley rats were scanned by 7.0T MRI to obtain the shape and position data of the cross section and gray matter of T8 to T10 spinal cord. Combined with data of position and shape of nerve conduction beam, the relevant data were obtained via Getdata software. Then the 3D graphics were made and converted to stereolithography (STL) format by using SolidWorks software. Photosensitive resin was used as the materials of spinal cord scaffolds. The bionic scaffolds were fabricated by 3D printer. ResultsMRI showed that the section shape of T8 to T10 segments of the spinal cord were approximately oval with a relatively long sagittal diameter of (2.20±0.52) mm and short transverse diameter of (2.05±0.24) mm, and the data of nerve conduction bundle were featured in the STL format. The spinal cord bionic scaffolds of the target segments made by 3D printer were similar to the spinal cord of rat in the morphology and size, and the position of pores simulated normal nerve conduction of rat spinal cord. ConclusionSpinal cord scaffolds produced by 3D printer which have similar shape and size of normal rat spinal cord are more bionic, and the procedure is simple. This technology combined with biomaterials is also promising in spinal cord repairing after spinal cord injury.