Objective To investigate the effect of the semi-joint prosthesis replacement in treating malignant tumors around the children’s knees. Methods Five children (aged 8-12 years) with malignant tumors around the proximal end ofthe tibia underwent the semi-joint prostheses replacement from March 2000 to June 2005. All the children had been diagnosed with osteosarcoma, which was graded as ⅡB by the Enneking staging system. The pathologic changes involved the upper segment of the tibia 9-11 cm in length. Before operation all the patients underwent puncture biopsy and standard chemotherapy. The lesion extent was determined by X-ray, CT and MRI, and then the size of the prosthesis was determined. The length of the prosthesis was 1-2 cm longer than that of the excised bone. After operation the patients were given neoadjuvant chemotherapy for 2 courses and they could walk with the help of a special brace 4 weeks postoperatively. Results All the 5 patients had a successful semi-joint prosthesis replacement exceptone patient who had a skin flap necrosis, and the wound healed after a flap grafting. The remaining patients had their wounds healed by first intention. The12-36 months’ follow-up revealed that all the patients had no metastasis or recurrence of the tumor and they were living and well except one patient who died oflung metastasis 8 months after operation. Conclusion The semi-joint prosthesis replacement in the limb salvage surgery for maligant tumors around the children’s knees has advantages of avoiding a damage to the normal osteoepiphysis, stabilizing the knee joint, and facilitating elongation of the limb in future. Italso creates the condition for total knee replacement in adults.
ObjectiveTo evaluate long-term radiographic and clinical effectiveness of total cervical disc replacement (TDR) with Prodisc-C prosthesis at a minimum of 10 years follow-up.MethodsThe clinical data of 118 patients with cervical disc degeneration disease (CDDD) treated with TDR by using Prodisc-C prosthesis between December 2005 and April 2008 were retrospectively analyzed. There were 66 males and 52 females, with the age of 25-62 years (mean, 46.8 years). There were 38 cases of cervical spondylotic radiculopathy, 28 cases of cervical spondylotic myelopathy, and 52 cases of mixed cervical spondylotic myelopathy. The operative segments were C3-7, including 90 cases of single segment, 20 cases of continuous double segments, and 8 cases of continuous three segments. A total of 154 Prodisc-C prostheses were used during the operation. The clinical effectiveness was evaluated by pain visual analogue scale (VAS) score, neck disability index (NDI), Japanese Orthopaedic Association (JOA) score, and Odom grade before and after operation. Imaging evaluation indicators included range of motion (ROM), sagittal lordosis angle, intervertebral disc height (IDH), and prosthesis displacement, subsidence, loosening, locking, and heterotopic ossification (HO), adjacent segment degeneration (ASD), and other complications. Patients were grouped according to whether HO or ASD occurred or not, the ROM of surgical segment was compared.ResultsAll patients were followed up 121-150 months (mean, 135.8 months). No revision operation was performed during the follow-up period. The VAS, NDI, JOA scores and Odom grades were significantly improved at 1 week after operation and last follow-up when compared with preoperative ones (P<0.05); VAS and NDI scores were further improved at last follow-up than those at 1 week after operation (P<0.05); there was no significant difference in JOA scores and improvement rates between at 1 week after operation and at last follow-up (P>0.05). The ROM of the whole cervical spine and the operative segment decreased at 1 week and 10 years after operation when compared with preoperative ones (P<0.05), but there was no significant difference in the other time points (P>0.05); there was no significant difference in the ROM between the upper adjacent segment (UAS) and the lower adjacent segment (LAS) at each time point after operation (P>0.05). There was no significant difference in sagittal lordosis angle of cervical spine before and after operation (P>0.05); the sagittal lordosis angle of operative segment increased significantly at 1 week, 6 months, 1 year, and 2 years after operation (P<0.05). The IDH of operative segment was significantly improved at each time point after operation (P<0.05), but there was no significant difference in IDH between UAS and LAS at each time point after operation (P>0.05). No prosthesis displacement, subsidence, or loosening occurred at each time point after operation. There was no significant difference of the prosthetic displacement and subsidence distance between all time points after 6 months after operation (P>0.05). At last follow-up, the incidence of prosthetic locking/fusion was 10.4%, showing no significant difference when compared with 6 months (1.9%) (P<0.05). The incidence of upper ASD and lower ASD was 1.3% and 2.6% respectively at 1 week after operation. The incidence of upper ASD and lower ASD increased gradually with time prolonging, and there were significant differences between different time points (P<0.05). The ROM of operative segment in ASD group was lower than that in non-ASD group at each time point after operation, but there was no significant difference (P>0.05). HO appeared in 58.4% of the segments at 6 months after operation, and the incidence of HO increased significantly with time, which was significantly different from that at 6 months after operation (P<0.05). The ROM of operative segments in HO group was significantly lower than that in non-HO group at 6 months, 2 years, 5 years, and 10 years after operation (P<0.05).ConclusionTDR has little effect on adjacent segments, although there are some imaging complications, it has no significant effect on the improvement of overall clinical effectiveness. Prodisc-C prosthesis can provide long-term, safe, and definite clinical effectiveness in the treatment of CDDD.
Objective To evaluate the clinical valueof the revision of total hip replacement(THR), to analyse the reason of the rev isions, and to discuss the main difficulties and measures to manage it.Methods From June 1998 to January 2002, 15 cases (15 hips) were revised on totalhip replacement. The reasons for revision in the cases were as follows:failure of primary operative techenique, loosening and sinking of the components, displacement of the prosthesis, erosion of the acetabulum, as well as fracture of the femoral stem. The main difficulties of the revision were:poor health condition of the patients; the remove of the prosthesis of the primary THR,especially the broken femoral stem and the cements; the loss of localbone. The measures to remove the broken femoral stem were described.ResultsAll cases were followed up 2.4 years on average: 2 patients died from heart disease and cerebrovascular disease respectively, while the good results were achieved in the others.No infection, dislocation, loosening, and other complications occurred. The good effects were related with following factors:mild degree of illness; no severe bone defect; most of the first femoral head replacement.Conclusion The revision of THRis a more difficult operation, so that the special instrument and equipment andoperative experience are required.
Objective Using the mono-energy reconstruction images and X-ray films to investigate whether the ABG Ⅱ short-stem could improve the filling ratio, stability, and alignment in the Dorr type C femur, compared with the Corail long-stem. MethodsAmong patients who were with Dorr type C femurs and treated with total hip arthroplasty between January 2006 and March 2012, 20 patients with a Corail long-stem (Corail group) and 20 patients with an ABG Ⅱ short-stem (ABG Ⅱ group) were randomly selected. The differences in gender, age, body mass index, and preoperative diagnoses between the two groups were not significant (P>0.05). The ABG Ⅱ group was with a mean follow-up of 142 months (range, 102-156 months), and the Corail group was with a mean follow-up of 107 months (range, 91-127 months). There was no significant difference in the Harris score and subjective satisfaction score between the two groups at last follow-up (P>0.05). At last follow-up, dual-energy CT scans with mono-energy image reconstruction were used to calculate the prosthetic filling ratio and to measure the alignment of the prosthesis in the coronal and sagittal positions. Stability assessment was performed based on X-ray films, and the subsidence distance was measured using EBRA-FCA software. ResultsX-ray film observation showed that the prostheses in the two groups were stable and no signs of loosening was found. The incidence of pedestal sign was significantly lower in the ABGⅡ group than in the Corail group (P<0.05), and the incidence of heterotopic ossification was significantly higher in the ABGⅡ group than in the Corail group (P<0.05). The subsidence distance of femoral stem in ABG Ⅱ group was significantly greater than that in Corail group (P<0.05), and the subsidence speed of femoral stem in ABG Ⅱ group was also greater than that in Corail group, but the difference was not significant (P>0.05). The overall prosthesis filling ratio was significantly higher in the ABG Ⅱ group than in the Corail group (P<0.05), while the coronal filling ratio at the lesser trochanter, 2 cm below the lesser trochanter, and 7 cm below the lesser trochanter were not significant (P>0.05). The results of prosthesis alignment showed that there was no significant difference in the sagittal alignment error value and the incidence of coronal and sagittal alignment error >3° between the two groups (P>0.05), while the coronal alignment error value in the ABG Ⅱ group was significantly greater than that in the Corail group (P<0.05). Conclusion Although the ABG Ⅱ short-stem avoids the distal-proximal mismatch of the Corail long-stem in the Dorr type C femur and thus achieves a higher filling ratio, it does not appear to achieve better alignment or stability.
Objective To design a novel stentless porcine aortic bioprosthesis and test the feasibility and its function in vitro after the valve was implanted by a modified method. Methods Six stentless porcine aortic bioprosthesis were divided into two groups according to different implantation, single layer suture group: new improvement stentless porcine aortic bioprosthesis sutured with single layer was implanted; double layer suture group: stentless porcine aortic bioprosthesis developmented by our laboratory used double layer suture was implanted. Each group contained three scales: 23 mm ,25 mm and 27 mm. Analogue ex vivo aortic valve replacement was performed , the feasibility of the new implantation was detected. Effective orifice area, transvalvular pressure gradient and regurgitation ratio were recorded at the cardiac output of 2.0 L/min, 3.5 L/min, 5.0 L/min and 7.0 L/min under the guideline of International Organization for tandardization （ISO）5840. Results The average aortic valve implantation time used for single layer suture and tradition double layer suture were 50 min and 70 min respectively. The transvalvular pressure gradient in the single layer suture group were significantly lower than those in double layer suture group under the flow of 5.0 L/min in 23 mm valve and 27 mm valve （13.51±0.51 mm Hg vs. 14.44±0.99 mm Hg, 7.36±0.19 mm Hg vs. 7.53±0.28 mm Hg；P＜0.01）;and the effective orifice area in the single layer suture group were larger than those in double layer suture group in the same case(1.87±0.06 cm2 vs. 1.76±0.08 cm2, 2.26±0.07 cm2 vs. 2.16±0.05 cm2；P＜0.01). There was no statistically difference in other parameters between both groups. Conclusion The novel design of new improvement stentless porcine aortic bioprosthesis used single layer suture has good hemodynamic characteristics as the nature structure . The modified suture method decrease the implantation time.Nemerical data of the evaluation in vitro show that the difference between single layer suture group and double layer suture group in effective orifice area,transvalvular pressure gradient and regurgitation ratio haveno statistical significance. This experiment is the foundation of the animal and clinical experiment in the future.
Objective To discuss the clinical application of preserving femoral neck in total hip arthroplasty and to analyze the early stage results.Methods From January 1999 to June 2001, 12 patients underwent total hip arthroplasty with preservation of femoral neck. We cut off the femoral head in infra-head position with improved Moore micro-incisions to reserve intact neck of femur. Thensuitable size of extra cup was selected and placed at 55° eversion angle. The internal cup, made from ultra high polymer poly thene and with ultra radius design, was placed at 45°eversion angle. Harris scores were recorded before operation, after operation and during the follow-up. During the follow-up, the X-rayfilms were taken to assess position, loosening of the prosthesis and ectopic ossification.Results All 12 patients were followed up 2-4.5years with an average of 3.1 years. The mean Harris score of hip elevated from 54 scores before operation to 92 scores of the last follow-up. Mild ectopic ossification occurred in 3 cases. There was no prosthesis loosening and femoral prosthesis setting, and only onepatient had mild bone absorption around femoral prosthesis.Conclusion Total hip arthroplasty with femoral neck preservation is a good option for the patients who need total hip arthroplasty for variable reasons, which is indicated for the patients whose femoral neck is intact with no osteoporosis.
ObjectiveTo investigate the femoral bone remodeling and long-term effectiveness of total hip arthroplasty (THA) with anatomic medullary locking (AML) prosthesis.MethodsThe clinical data of 24 cases (26 hips) who were treated with THA with AML prosthesis between November 1997 and January 2003 were retrospectively analyzed. There were 12 males and 12 females with an age of 32-69 years (mean, 53.7 years). There were 5 cases (5 hips) of avascular necrosis of the femoral head, 6 cases (7 hips) of secondary osteoarthritis of the hip dysplasia, 6 cases (6 hips) of femoral neck fracture, 2 cases (2 hips) of primary osteoarthritis, 3 cases (3 hips) of revision surgery, 1 case (2 hips) of ankylosing spondylitis, 1 case (1 hip) of femoral head fracture. The patients were followed up at immediate, 6 weeks, 3 months, 6 months, 1 year, and then every year after operation for imaging evaluation (X-ray film was taken immediately after operation to evaluate the femoral isthmus compression, Engh standard was used to evaluate the biological fixation of the femoral shaft prosthesis, and Brooker method was used to evaluate the occurrence of heterotopic ossification); bone reconstruction evaluation [reconstruction of prosthesis and bone interface (type of bone reaction, Gruen zone, incidence, and occurrence time were recorded), reconstruction of bone around prosthesis (proximal femur stress shielding bone absorption was evaluated according to Engh and Bobyn methods, and bone mineral density change rate was measured)]; clinical efficacy evaluation [Harris score for efficacy, visual analogue scale (VAS) score for thigh pain].ResultsAll patients were followed up 15 years and 2 months to 20 years and 4 months, with a median of 16 years and 6 months. At immediate after operation, 24 hips (92.3%) had good femoral isthums compression, 24 hips (92.3%) had good bone ingrowth. Heterotopic ossification occurred in 2 patients with degree 1, 2 patients with degree 2, and 1 patient with degree 3 at 3-6 months after operation. Hyperplastic bone reactions were more common in Gruen 2, 3, 4, 5, 6, 10, 11, and 12 zones, mainly occurring at 6-20 months after operation, with the incidence of 3.8%-69.2%, with the highest incidence of spot welding. All absorptive bone reactions were osteolysis, which was common in Gruen 1 and 7 zones, and mainly occurred at 8 years after operation, with an incidence of 42.3%. No clear line (area) or enlarged sign of medullary cavity was observed. Twenty-one hips (80.8%) had 1 degree stress shieding, and 5 hips (19.2%) had 2 degree stress shieding. It mainly occurred at 10-24 months after operation in Gruen 1 and 7 zones. Dual energy X-ray absorptiometry showed that bone mineral density mainly decreased in Gruen 1, 2, 6, and 7 zones, mainly increased in Gruen 3, 4, and 5 zones. Bone mineral density loss progressed slowly after 2 years of operation, and it was stable in 5-8 years, but decreased rapidly in 8-9 years, and stabilized after 10 years. The Harris score increased from 51.1±6.2 before operation to 88.3±5.1 at last follow-up (t=–21.774, P=0.000). Mild thigh pain occurred in only 2 cases (7.7%) with the VAS score of 2. No aseptic loosening or revision of femoral prosthesis occurred during the follow-up.ConclusionThe application of AML prosthesis in THA has a good bone remodeling and a good long-term effectiveness.
Objective To summarize the application progress of three-dimensional (3D) printed metal prosthesis in joint surgery. Methods The related literature was extensively reviewed. The effectiveness of 3D printed metal prosthesis in treatment of joint surgery diseases were discussed and summarized, including the all key issues in prosthesis transplantation such as prosthesis stability, postoperative complications, bone ingrowth, etc. Results 3D printed metal prosthesis has good matching degree, can accurately reconstruct and restore joint function, reduce operation time, and achieve high patient satisfaction in short- and medium-term follow-up. Its application in joint surgery has made good progress. Conclusion The personalized microporous structure prostheses of different shapes produced by 3D printing can solve the problem of poor personalized matching of joints for special patients existing in traditional prostheses. Therefore, 3D printing technology is full of hope and will bring great potential to the reform of orthopedic practice in the future.
ObjectiveTo evaluate the effect of the surgeon’s handedness on the distribution of prosthesis during primary total knee arthroplasty (TKA).MethodsA retrospective analysis was performed on 86 patients (100 knees) with primary TKA completed by the same right-handed surgeon between December 2016 and December 2018, including 72 cases of single knee and 14 of bilateral knees. The patients were divided into dominant group (right side) and non-dominant group (left side) according to the operating position of the surgeon and each group had 50 knees. There was no significant difference in gender, age, body mass index, disease duration, clinical diagnosis, preoperative Hospital for Special Surgery (HSS) score, and other general data between the two groups (P>0.05). The operation time and complications were recorded in both groups. The function of knee was evaluated by HSS score. Hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), and mechanical medial proximal tibial angle (mMPTA) were measured by using X-ray film of full-length lower extremity before TKA and at 2 weeks after TKA that were used to evaluate the coronal position of the prosthesis. Posterior distal femoral angle (PDFA) and posterior proximal tibial angle (PPTA) were measured by using lateral X-ray films at 3 months after operation that were used to evaluate the sagittal position of the prosthesis.ResultsThere was no significant difference in operation time between the two groups (t=−1.128, P=0.262). One case of posterior tibial artery thrombosis occurred in the dominant group, and 1 case of poor healing of the incision occurred in each of the dominant group and the non-dominant group. Patients in both groups were followed up 12-34 months with an average of 22.0 months. The HSS scores at last follow-up were 87.2±4.3 in the dominant group and 86.8±5.0 in the non-dominant group. There was no significant difference between the two groups (t=0.471, P=0.639). No complications such as periprosthetic infection, prosthetic loosening, or periprosthetic fracture occurred during follow-up. There was no significant difference in the HKA, mLDFA, and mMPTA between the two groups before and after operation (P>0.05). The differences in the incidence of sagittal femoral prosthesis malposition and PDFA between the two groups were significant (P<0.05); however, there was no significant difference in the PPTA, the rate of femoral prosthesis distributed in the neutral position, the incidence of over-flexed femoral prosthesis, and the incidence of anterior femoral notch (P>0.05).ConclusionThe surgeon’s handedness is one of the factors affecting the placement of the sagittal femoral prosthesis in primary TKA. The incidence of sagittal femoral prosthesis malposition could increase when the surgeon performs on the non-dominant side.
ObjectiveTo explore the feasibility of establishment of a artificial joint aseptic loosening mouse model by cobalt-chromium particles stimulation.MethodsTwenty-four 8-week-old male severe combined immunodeficient (SCID) mice were divided into experimental group (n=12) and control group (n=12). The titanium nail was inserted into the tibial medullary cavity of mouse in the two groups to simulate artificial joint prosthesis replacement. And the cobalt-chromium particles were injected into the tibial medullary cavity of mouse in experimental group. The survival of the mouse was observed after operation; the position of the titanium nail and the bone mineral density of proximal femur were observed by X-ray film, CT, and Micro-CT bone scanning; and the degree of dissolution of the bone tissue around the tibia was detected by biomechanical test and histological staining.ResultsTwo mice in experimental group died, and the rest of the mice survived until the experiment was completed. Postoperative imaging examination showed that there was no obvious displacement of titanium nails in control group, and there were new callus around the titanium nails. In experimental group, there was obvious osteolysis around the titanium nails. The bone mineral density of the proximal tibia was 91.25%±0.67%, and the maximum shear force at the tibial nail-bone interface was (5.93±0.85) N in experimental group, which were significantly lower than those in control group [102.07%±1.87% and (16.76±3.09) N] (t=5.462, P=0.041; t=3.760, P=0.046). Histological observation showed that a large number of inflammatory cells could be seen around the titanium nails in experimental group, while there was no inflammatory cells, and obvious bone tissue formation was observed in control group.ConclusionThe artificial joint aseptic loosening mouse model can be successfully established by cobalt-chromium particles stimulation.