ObjectiveTo explore the application of three-dimensional (3-D) printing technique in repair and reconstruction of maxillofacial bone defect. MethodsThe related literature on the recent advance in the application of 3-D printing technique for repair and reconstructing maxillofacial bone defect was reviewed and summarized in the following aspects:3-D models for teaching, preoperative planning, and practicing; surgical templates for accurate positioning during operation; individual implantable prosthetics for repair and reconstructing the maxillofacial bone defect. Results3-D printing technique is profoundly affecting the treatment level in repair and reconstruction of maxillofacial bone defect. Conclusion3-D printing technique will promote the development of the repair and reconstructing maxillofacial bone defect toward more accurate, personalized, and safer surgery.
ObjectiveTo investigate the clinical application of three-dimensional (3D) printing technique combined with a new type of thoracic pedicle screw track detector in thoracic pedicle screw placement.MethodsAccording to the characteristics of thoracic pedicle and common clinical screw placement methods, a new type of thoracic pedicle screw track detector was independently developed and designed. The clinical data of 30 patients with thoracic vertebrae related diseases who underwent posterior thoracic pedicle screw fixation between March 2017 and January 2020 were retrospectively analysed. Among them, there were 18 males and 12 females with an average age of 56.3 years (range, 32-76 years). There was 1 case of thoracic disc herniation, 4 cases of thoracic canal stenosis, 2 cases of ossification of posterior longitudinal ligament of thoracic vertebra, 16 cases of thoracic trauma, 2 cases of thoracic infection, and 5 cases of thoracic canal occupation. Three-dimensional CT of the thoracic vertebra was routinely performed preoperatively, and the model of the patient’s thoracic vertebra was reconstructed and printed out. With the assistance of the model, preoperative simulation was performed with the combination of the new type thoracic pedicle screw track detector, and detected no nails after critical cortical damage. During operation, one side was randomly selected to use traditional hand screws placement (control group), and the other side was selected to use 3D printing technique combined with new type thoracic pedicle screw track detector to assist thoracic pedicle screws placement (observation group). The single screw placement time, adjustment times of single screw, and blood loss during screw placement were compared between the two groups. The accuracy of screw placement in the two groups was evaluated according to postoperative CT imaging data.ResultsThe single screw placement time, adjustment times of single screw, and blood loss during screw placement in the observation group were significantly less than those in the control group (P<0.05). Postoperative CT examination showed that the observation group had 87 screws of grade 1, 3 screws of grade 2, and the acceptable screw placement rate was 100% (90/90); the control group had 76 screws of grade 1, 2 screws of grade 2, 11 screws of grade 3, and 1 screw of grade 4, and the acceptable screw placement rate was 86.7% (78/90); showing significant difference in screw placement between the two groups (χ2=12.875, P=0.001). All patients were followed up 6-18 months, with an average of 11.3 months. There was no complication of vascular, nerve, spinal cord, or visceral injury, and screws or rods broken, and no patient was revised.ConclusionThe 3D printing technique combined with the new type of thoracic pedicle screw track detector assisted thoracic pedicle screw placement is convenient, and significantly improves the accuracy and safety of intraoperative screw placement, and overall success rate of the surgery.
Objective A prospective study was conducted to investigate the feasibility and effectiveness of three-dimensional printed in vitro guide plates assisted hip arthroscopy in the treatment of Cam-type femoroacetabular impingement (FAI). Methods The clinical data of 25 patients with Cam-type FAI who met the selection criteria between December 2016 and September 2022 were collected. There were 13 males and 12 females with an average age of 42 years (range, 19-66 years). The disease duration ranged from 3 to 120 months, with an average of 22.2 months. The preoperative range of internal rotation-external rotation was (28.70±4.50)°, α angle was (69.04±0.99)°, visual analogue scale (VAS) score was 6.5±0.2, and modified Harris hip score (HHS) was 50.5±0.7. All patients were treated with hip arthroscopy assisted by three-dimensional printed in vitro guide plate. The occurrence of complications was observed postoperatively, α angle of the affected hip joint was measured on Dunn X-ray film, and the glenoid labrum injury was observed by MRI. The percentage of overlap between the Cam plasty area and the preoperative simulated grinding area was calculated by three-dimensional CT+reconstruction. The effectiveness was evaluated by VAS score and modified HHS score. ResultsPostoperative dorsalis pedis numbness occurred in 1 case, and the symptoms disappeared after 1 month of conventional drug treatment such as neurotrophy. Two cases of perineal skin injury occurred, and healed after symptomatic treatment. There was no male erectile dysfunction, deep incision infection, pulmonary embolism, or other serious complications occurred. The percentage of overlap between the Cam plasty area and the preoperative simulated grinding area was 81.6%-95.3%, with an average of 89.8%. All 25 patients were followed up 6-12 months, with an average of 8 months. At last follow-up, the range of internal rotation-external rotation was (40.10±2.98)°, α angle was (43.72±0.84)°, VAS score was 1.8±0.2, and the modified HHS score was 72.1±1.3, which significantly improved when compared with preoperative ones (P<0.05). ConclusionThe treatment of Cam-type FAI with three-dimensional printed in vitro guide plates assisted hip arthroscopy is safe and feasible, and can achieve good effectiveness.
ObjectiveTo evaluate the clinical significance of individualized reference model of sagittal curves and navigation templates of pedicle screw by three-dimensional printing technique for thoracolumbar fracture with dislocation. MethodsBetween February 2011 and November 2013, 42 patients with thoracolumbar fracture and dislocation undergoing pedicle screw fixation were divided into 2 groups:traditional pedicle screw internal fixation by fluoroscopy assistant was used in 24 cases (control group), and individualized reference model of sagittal curves and navigation templates of pedicle screw were used in 18 cases (trial group). There was no significant difference in gender, age, injury causes, segment, degree of dislocation, and Frankel classification between 2 groups (P>0.05). The operation time, intraoperative blood loss, perspective times, and dislocation rate, sagittal angle recovery rate at different time were compared. The success rate of pedicle screw insertion, sagittal screw angle, and Frankel classification were compared. The angle between sagittal screws, difference of screw entry point at horizontal position, and difference of screw inclined angle were compared. ResultsThe operating time, intraoperative blood loss, and perspective times in trial group were significantly lower than those in control groups (P<0.05). All the patients were followed up 12-40 months (mean, 22 months). The dislocation rate at immediate after operation and last follow-up were significantly improved when compared with preoperative value in 2 groups (P<0.05). At immediate after operation and last follow-up, the dislocation rate and sagittal angle recover rate in trial group were significantly better than those in control group (P<0.05). There were significant differences in the one-time success rate, final success rate of pedicle screw insertion, and saggital screw angle between 2 groups (χ2=9.38, P=0.00; χ2=10.95, P=0.00; χ2=13.43, P=0.00). The angle between sagittal screws, difference of screw entry point at horizontal position, and difference of screw inclined angle in trail group were significantly less than those in control group (P<0.05). There was significant difference in the Frankel classification between 2 groups at last follow-up (Z=-1.99, P=0.04). ConclusionThe application of individualized reference model of sagittal curves and navigation templates of pedicle screw by three-dimensional printing technique for thoracolumbar fracture with dislocation has the advantages of shorter operation time, less intraoperative blood loss, better recovery of thoracolumbar dislocation, and better Frankel classification.
ObjectiveTo investigate the effect of three-dimensional (3D) printing guide plate on improving femoral rotational alignment and patellar tracking in total knee arthroplasty (TKA).MethodsBetween January 2018 and October 2018, 60 patients (60 knees) with advanced knee osteoarthritis who received TKA and met the selection criteria were selected as the study subjects. Patients were randomly divided into two groups according to the random number table method, with 30 patients in each group. The TKA was done with the help of 3D printing guide plate in the guide group and following traditional procedure in the control group. There was no significant difference in gender, age, disease duration, side, and preoperative hip-knee-ankle angle (HKA), posterior condylar angle (PCA), patella transverse axis-femoral transepicondylar axis angle (PFA), Hospital for Special Surgery (HSS) score, and American Knee Society (AKS) score (P>0.05).ResultsAll incisions healed by first intention and no complications related to the operation occurred. All patients were followed up 10-12 months, with an average of 11 months. HSS score and AKS score of the two groups at 6 months after operation were significantly higher than those before operation (P<0.05), but there was no significant difference between the two groups (P>0.05). Postoperative X-ray films showed that the prosthesis was in good position, and no prosthesis loosening or sinking occurred during follow-up. HKA, PCA, and PFA significantly improved in the two groups at 10 months after operation compared with those before operation (P<0.05). There was no significant difference in HKA at 10 months between the two groups (t=1.031, P=0.307). PCA and PFA in the guide group were smaller than those in the control group (P<0.05).ConclusionApplication of 3D printing guide plate in TKA can not only correct the deformity of the knee joint and alleviate the pain symptoms, but also achieve the goal of the accurate femoral rotation alignment and good patellar tracking.
ObjectiveTo investigate whether subchondral bone microstructural parameters are related to cartilage repair during large osteochondral defect repairing based on three-dimensional (3-D) printing technique. MethodsBiomimetic biphasic osteochondral composite scaffolds were fabricated by using 3-D printing technique. The right trochlea critical sized defects (4.8 mm in diameter, 7.5 mm in depth) were created in 40 New Zealand white rabbits (aged 6 months, weighing 2.5-3.5 kg). Biomimetic biphasic osteochondral composite scaffolds were implanted into the defects in the experimental group (n=35), and no composite scaffolds implantation served as control group (n=5); the left side had no defect as sham-operation group. Animals of experimental and sham-operation groups were euthanized at 1, 2, 4, 8, 16, 24, and 52 weeks after operation, while animals of control group were sampled at 24 weeks. Subchondral bone microstructural parameters and cartilage repair were quantitatively analyzed using Micro-CT and Wayne scoring system. Correlation analysis and regression analysis were applied to reveal the relationship between subchondral bone parameters and cartilage repair. The subchondral bone parameters included bone volume fraction (BV/TV), bone surface area fraction (BSA/BV), trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular spacing (Tb.Sp). ResultsIn the experimental group, articular cartilage repair was significantly improved at 52 weeks postoperatively, which was dominated by hyaline cartilage tissue, and tidal line formed. Wayne scores at 24 and 52 weeks were significantly higher than that at 16 weeks in the experimental group (P<0.05), but no significant difference was found between at 24 and 52 weeks (P>0.05); the scores of experimental group were significantly lower than those of sham-operation group at all time points (P<0.05). In the experimental group, new subchondral bone migrated from the surrounding defect to the centre, and subchondral bony plate formed at 24 and 52 weeks. The microstructural parameters of repaired subchondral bone followed a "twin peaks" like discipline to which BV/TV, BSA/BV, and Tb.N increased at 2 and 16 weeks, and then they returned to normal level. The Tb.Sp showed reversed discipline compared to the former 3 parameters, no significant change was found for Tb.Th during the repair process. Correlation analysis showed that BV/TV, BSA/BV, Tb.Th, Tb.N, and Tb.Sp were all related with gross appearance score and histology score of repaired cartilage. ConclusionSubchondral bone parameters are related with cartilage repair in critical size osteochondral repair in vivo. Microstructural parameters of repaired subchondral bone follow a "twin peaks" like discipline (osteoplasia-remodeling-osteoplasia-remodeling) to achieve reconstruction, 2nd week and 16th week are critical time points for subchondral bone functional restoration.
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.
ObjectiveTo summarize the latest research development of the application of digital design and three-dimensional (3-D) printing technique on individualized medical treatment. MethodsRecent research data and clinical literature about the application of digital design and 3-D printing technique on individualized medical treatment in Xi'an Jiaotong University and its cooperation unit were summarized, reviewed, and analyzed. ResultsDigital design and 3-D printing technique can design and manufacture individualized implant based on the patient's specific disease conditions. And the implant can satisfy the needs of specific shape and function of the patient, reducing dependence on the level of experience required for the doctor. So 3-D printing technique get more and more recognition of the surgeon on the individualized repair of human tissue. Xi'an Jiaotong University is the first unit to develop the commercial 3-D printer and conduct depth research on the design and manufacture of individualized medical implant. And complete technological processes and quality standards of product have been developed. ConclusionThe individualized medical implant manufactured by 3-D printing technique can not only achieve personalized match but also meet the functional requirements and aesthetic requirements of patients. In addition, the individualized medical implant has the advantages of accurate positioning, stable connection, and high strength. So 3-D printing technique has broad prospects in the manufacture and application of individualized implant.
ObjectiveTo review the current research status of in situ three-dimensional (3-D) printing technique and future trends. MethodsRecent related literature about in situ 3-D printing technique was summarized, reviewed, and analyzed. ResultsBased on the cl inical need for surgical repair, in situ 3-D printing technique is in the preliminary study, mainly focuses on in situ dermal repair and bone and cartilage repair, and succeeds in experiments, but there are still a lot of problems for cl inical application. ConclusionWith the development of in situ 3-D printing technique, it will provide patients with real-time and in situ digital design and 3-D printing treatment with a timely and minimally invasive surgical repair process. It will be widely used in the future.
ObjectiveTo evaluate the clinical significance of individualized reference model of sagittal curves by three-dimensional (3D) printing technique and computer-aided navigation system for lumbar spondylolisthesis. MethodsBetween February 2011 and October 2012, 66 patients with lumbar spondylolisthesis underwent posterior lumbar interbody fusion (PLIF) by traditional operation in 36 cases (control group) and by individualized reference model of sagittal curves by 3D printing technique and computer-aided navigation system in 30 cases (trial group). There was no significant difference in gender, age, disease duration, segment, type of disease, degree of spondylolisthesis, and preoperative the visual analogue scale (VAS) of low back pain and leg pain between 2 groups (P>0.05). The operation time, blood loss, fluoroscopy times, VAS score of low back pain and leg pain were compared between 2 groups; the sagittal screw angle (SSA), accuracy rate of pedicle screw, Taillard index, disc height recovery rate, and sagittal angle recovery rate were compared between 2 groups. ResultsThere was no significant difference in operation time and blood loss between 2 groups (P>0.05). But fluoroscopy times of control group were significantly higher than those of trial group (P<0.05). One case had radicular symptoms after operation in control group. The patients of 2 groups were followed up 24-36 months (mean, 26 months). The VAS scores of low back pain and leg pain at last follow-up were significantly better than pre-operative scores in 2 groups (P<0.05); VAS score of low back pain in trial group at last follow-up was significantly lower than that in control group (P<0.05). The accuracy rate of pedicle screw was 81.9% (118/144) in control group and 91.7% (110/120) in trial group, showing significant difference (χ2=5.25, P=0.03). There was significant difference in SSA between 2 groups at immediate after operation (t=-6.21, P=0.00). At immediate after operation and last follow-up, Taillard index, disc height recovery rate, and sagittal angle recovery rate in trial group were significantly better than those in control group (P<0.05). ConclusionPLIF by individualized reference model of sagittal curves by 3D printing technique and computer-aided navigation system can effectively correct spondylolisthesis, recover the lumbar sagittal angle and improve the VAS score of low back pain though it has similar operation time and blood loss to traditional PLIF.