Study of clinical, subclinical features and corrective surgery outcomes of lower limb axis in patients with osteogenesis imperfecta

characteristics of the disease to get good results. The results of the research are a valuable contribution to the development of the Orthopaedics and Trauma Surgery specialization and has a highly humanity. THESIS STRUCTURE The thesis consists of 126 pages, with 4 chapters: Introduction - 02 pages, Chapter 1: Litlerature review 30 pages, Chapter 2: Objectives and research methods - 25 pages, Chapter 3: Results - 35 pages, Chapter 4: Discussion - 30 pages, Conclusions - 02 pages and Recommendations 01 page. The thesis has 49 tables, 34 figures, 7 images, 108 references including 4 Vietnamese documents and 104 English documents. Chapter 1. LITLERATURE REVIEW 1.1. Osteogenesis imperfecta disease 1.1.1. Clinical characteristics and classification 1.1.1.1. Clinical: Specific features are the long bones easy to fractures, blue scabs, imperfect formation of teeth, hearing loss or loss. 1.1.1.2. Classification of Osteogenesis imperfecta disease Sillence (1979) is classified into 4 types, based on clinical features, X-ray features and family history. 1.2. Subclinical 1.2.1. Characteristics of bone deformation on X-ray film 1.2.1.1 Long bones - Bone deformation is a common deformation.           - Images of cystic bone or calcified "popcorn" in onions, seen in type III. - Many bold images in the bones. 1.2.1.2. Spine - Scoliosis of the lumbar spine 1.2.1.3. The skull - Skull with few bones or multiple skulls 1.2.2. Biochemical characteristics of blood and electrolytes 1.2.2.1. Blood biochemical test Complete blood count tests are within normal limits 1.2.2.2. Electrolytes Concentrations of calcium ion, total serum calcium are within normal limits. 1.3. Diagnose 1.5.1. Specific Diagnose Based on clinical symptoms, X-ray images, history of fractures and family history. 1.4. Treatment 1.4.1. In the world + Medical treatment: Medical treatment with intravenous bisphosphonate. + Surgical treatment: Topouchian V. et al (2006) used a pair of cognitive equations for CXCT. 1.4.2. In Viet Nam + Medical treatment: Vietnam is using Rauch's treatment regimen (2003). + Surgical treatment: Nguyen Ngoc Hung et al. (2016) reported on the results of the surgery to fix the internal bone axis in the long lower limb body in patients with OI equal to 1 intramedually nail for 24 patients with 29 femur undergoing surgery, the time after the bone to heal. surgery from 12-18 weeks, 10 patients have the prospect of walking, 10 patients have access to support equipment and 4 patients still have to sit in a wheelchair, the average time of fractures, curved nails, buds sticking out of the bone 17 months after surgery. Chapter 2. RESEARCH SUBJECTS AND METHODS 2.1. Object, time, place of study Including 42 patients with OI at Military Medical Hospital 7A - Military Region 7, from January 2012 to December 2016. 2.1.1. Inclusion criteria + Patients diagnosed with OI based on clinical diagnosis criteria of author Jin T.Y. et al (2016): - Idiopathic and / or recurrent fractures - Blue sclerae - Dentinogenesis imperfecta - Hearing loss reduced Clinical diagnosis of OI when at least 2 of the 4 criteria above. + Patients and their families agree to participate in the study + Patient's medical record has all research criteria 2.1.2. Standard surgical treatment: + Patient could not walk due to limb deformation + Fractures many families require surgery + Brittle bones + Surgery age 2 years or older 2.1.3. Exclusion criteria + Do not have enough medical records and X-ray film archives + Patients do not agree to participate in the study (the family requires no surgery) + Tests and clinical are not OI diseases + There are combined diseases not stable treatment + Skeletal deformation but patients can walk 2.2. Methodology 2.2.1. Study design + Step 1: Conducting research, cross-sectional description, without control group based on a consistent research sample form from which to reach the conclusion of goal 1. + Step 2: Select a group of patients with lower limb surgery to conduct intervention and evaluate the results of surgical treatment to address goal 2. 2.2.2. Sample size Because this is a rare condition, in this study, we chose the convenient sampling method, including all subjects that meet the criteria for selection in the study subjects. The target sample 1 is 42 patients, the target sample 2 is 33 patients 2.3. Research content 2.3.1. Target 1 2.3.1.1. Clinical research + Age, gender, family history, history of fractures, number of fractures, frequency of fractures, location of fractures, location of first fractures, previous treatment of fractures in lower limbs. + Functional symptoms: aching bones, dizziness, constipation, easy bruising + Physical symptoms: Triangular face, blue eyes, strengthening imperfections, hearing or hearing loss, chest, spine, clinical bone deformities, preoperative movement: Self-sitting, crawl with your butt, stand on your own, stand with support, walk on your own, walk with support. 2.3.1.2. Research on subclinical + X-ray: Skull bone: Investigate the presence of multiple skull bones Long bones: Distorted deformity, calcification of popcorn, dark veins in onions. Spine bone: Scoliosis image, collapsed vertebra. + Blood chemistry: The concentration of Glucose, SGOT, SGPT, Creatinine, Urea compared to normal values. + Electrolyte: Blood calcium concentration: Ca++, total calcium compared to normal values. 2.3.2. Target 2 2.3.2.1. Internal osteosurgery uses self-made kits to treat deformities of the lower limbs in imperfect bone formation - Self-created kits for root canal drilling at cut bone section. - Tools for driving through double nails. - Tools for piercing heads on tibia. - Homemade locking brace (point locking brace). 2.3.2.2. Result evaluation + Evaluate early results - In surgery: Surgical time, blood loss, surgical site, surgical methods, number of bone / bone section / cut, combined fracture bone tool, root canal drilling, amount of transfusion blood, accidents, dialysis accident management, reinforced with flour troughs, shaft alignment results - After surgery: ≤ 1 month after surgery: Evolution at the incision, combined fracture bone techniques, complications and management measures. Postoperative assessment at follow-up visits: ≥ 1 month, ≥ 3 months, ≥ 6 months after surgery: Distortion of bone, movement, bone axis (straight axis: Deformation angle 200). Instrument alignment: Nails located in the canal, bent nails, broken nails, nails protruding from the shell bone or nails into the joint socket, turn on the screw. Bad condition of 2 nails on normal X-ray film. Fracture fracture, callus grade. + Evaluate far results Time of re-examination: ≥ 12 months, ≥ 24 months, ≥ 36 months). The evaluation criteria: deformation of bone, movement, axial axis, instrument alignment, the condition of sliding 2 nails in case of using double nails, broken bones, fractured positions. Evaluation of surgical results based on the score sheet of El Sobky M. et al. The index of life satisfaction after surgery is assessed on the basis of Likert scale. Chapter 3. RESEARCH RESULTS 3.1 Clinical features and X-ray image of long bones and bones skull, spine, blood biochemical tests and electrolytes in patients with Osteogenesis imperfecta. 3.1.1. Age and gender Table 3.2. Age characteristics of surgical patients group (n = 33) Criteria Sex Total Rate % Males Females n Rate % n Rate % From 2 to < 6 4 25,0 4 23,5 8 24,2 6 - < 10 2 12,5 5 29,4 7 21,2 10 - < 18 10 62,5 6 35,3 16 48,5 ≥ 18 0 0,0 2 11,8 2 6,1 Total 16 100 17 100 33 100 The group of surgical patients is mainly in the developing age, accounting for the most, from the age of 10 - <18. 3.2. The results of treating lower limb bone deformities in Osteogenesis imperfeta disease using self-created kit 3.2.1. The early results + Postoperative results: At the time of follow-up examination: ≥ 1, ≥ 3, ≥ 6 months after surgery Table 3.35. X-ray test results (n = 53, n: Number of bones) X-rays results ≥ 1 month (n = 49) Rate % ≥ 3 months (n = 47) Rate % ≥ 6 months (n=45) Rate % Callus Grade 1 47 95,92 0 0 0 0 Grade 1 0 0 45 95,74 0 0 Grade 1 0 0 0 0 43 95,56 No callus 2 4,08 2 4,26 2 4,44 Total 49 100 47 100 45 100 After ≥ 1 month and ≥ 3 months, there are 2 cases of no calcification. After ≥ 6 months, there are 2 cases non-union and re-operated Table 3.36. Results of bone alignment and bone combination method (n = 53, n: Number of bones) X-ray Results Method Location Femur Tibia ≥ 1 month ≥ 3 months ≥ 6 months ≥ 1 months ≥ 3 months ≥ 6 months n n n n n n Bone axis Straight 1 nail 5 5 5 5 4 5 2 nails 33 32 30 6 6 5 No straight 1 nail 0 0 0 0 0 0 2 nails 0 0 0 0 0 0 Nail + Screw 0 0 0 0 0 0 Total 38 37 35 11 10 10 After ≥ 1 month, 49 bone positions were operated on straight axes. After ≥ 3 months, there are 47 bones and after ≥ 6 months, there are 45 surgery bones, the cases are straight axis. Table 3.37. Result of bone combination means and bone combination method (n = 53, n: Number of bones) X-ray Results Method Location Femur Tibia ≥ 1 month ≥ 3 months ≥ 6 months ≥ 1 months ≥ 3 months ≥ 6 months n n n n n n Instrument alignment Normal 1 nail 5 5 5 5 4 5 2 nails 33 32 30 6 6 5 Curved 1 nail 0 0 0 0 0 0 2 nails 0 0 0 0 0 0 Extruding 1 nail 0 0 0 0 0 0 2 nails 0 0 0 0 0 0 Screw unstuck Nail + Screw 0 0 0 0 0 0 Total 38 37 35 11 10 10 After ≥ 1 month on 49 bone fixed positions, there were no complications. Followup after ≥ 3 months of 47 locations and after ≥ 6 months of 45 bone fixed locations, there are no cases where bone fixed tool bends, nails protrude from the bone shell and screw splint. Table 3.38. Result of 2 nails sliding according to the development (n = 43, n: Number of bones using 2 intramedullary nails) X-ray Results Method Location Femur Tibia ≥ 1 month ≥ 3 months ≥ 6 months ≥ 1 months ≥ 3 months ≥ 6 months n n n n n n 2 nails sliding Yes 2 nails 0 5 27 0 6 5 No 2 nails 31 25 3 8 2 0 Total 31 30 30 8 8 5 From the 3rd month onwards there were 2 spikes relative to bone growth. Specifically, after ≥ 3 months, there are 11/36 cases (30.6%) with skidding 2 nails. After ≥ 6 months 32/35 cases (91.4%) failed 2 nails according to bone growth. Table 3.39. Results of evaluating motor postoperative (n: Number of patients) Motion Before Surgery (n=33) ≥ 1 month (n=29) ≥ 3 months (n=28) ≥ 6 months (n=28) n (%) n (%) n (%) n (%) Independent sitting 13(39,4) 22(75,9) 5(17,9) 1(3,6) Crawling/bottom shuffling 17(51,5) 5(17,2) 9(32,1) 9(32,1) Independent stand 1(3,0) 0(0,0) 1(3,6) 0(0,0) Assisted sit 0(0,0) 2(6,9) 4(14,9) 1(3,6) Independent walk 1(3,0) 0(0,0) 0(0,0) 9(32,1) Assisted walk 1(3,0) 0(0,0) 9(32,1) 8(25,6) Total 33 29 28 28 There is a significant improvement in motor skills in patients after surgery ≥ 3 - ≥ 6 months compared to before surgery. The increase is statistically significant. 3.2.2. Evaluating distal results after orthopedic surgery (after ≥ 12 months) Table 3.40. Classification by time of inspection (n = 33, n: Number of patients) Time of follow-up n Rate % ≥ 12 -< 24 months 24 72,73 ≥ 24 - < 36 months 24 72,73 ≥ 36 months 17 51,52 Avarage time of follow-up 32,5 (months) Patients with the shortest follow-up time for ≥ 24 months (24 patients) accounted for 72.7%, the longest follow-up time was ≥ 36 months (17 patients) accounted for 51.5%. The results showed that the average follow-up time in the study reached 32.5 months. Table 3.41. Results of bone instrument alignment and bone fixation method (n = 53, n: Number of bones) X-ray Results Method Location Femur Tibia ≥ 12 months ≥ 24 months ≥ 36 months ≥ 12 months ≥ 24 months ≥ 36 months n n n n n n Axial of limb Aligned 1 nail 4 3 2 5 1 1 2 nails 25 21 8 10 8 4 Nonaligned 1 nail 0 3 3 0 1 1 2 nails 0 2 1 0 0 0 Total 29 29 14 15 10 6 Results to reach ≥ 12 months of follow-up with 44 bone positions, the cases are monitored straight axis. At the time of ≥ 24 months, there were 6/39 cases with bone curvature but the level of deformation assessment was not enough to be re-operated. Reaching the time of ≥ 36 months of monitoring 20 bone positions, there were up to 5 cases of axial curvature which were detected before but the level did not increase much. Table 3.42. Result of bone instrument alignment and bone fixation method (n = 53, n: Number of bones) X-ray Results Method Location Femur Tibia ≥ 12 months ≥ 24 months ≥ 36 months ≥ 12 months ≥ 24 months ≥ 36 months Instrument alignment Normal 1 nail 4 3 2 5 1 1 2 nails 25 22 8 10 8 4 Curved 1 nail 0 0 0 0 0 0 2 nails 0 0 0 0 0 0 Extruding 1 nail 0 3 3 0 1 1 2 nails 0 1 1 0 0 0 Screw unstuck 1 nail 0 0 0 1(*) 0 0 Total 29 29 14 15 10 6 (*): 1 case using nail + Screw Results to reach ≥ 12 months tracking 44 locations that have instrument alignment, the cases were followup without complications of intramedullary nail, 1 case of screw splint. Reaching time ≥ 24 and ≥ 36 months, there are 5 cases where the nail shoots to the bone shell, not enough to be re-operated. Table 3.43. Result of 2 nails sliding according to bone growth (n = 43, n: Number of bones using 2 intramedullary nails) X-ray Result Bone fixation method Location Femur Tibia ≥ 12 month ≥ 24 months ≥ 36 months ≥ 12 months ≥ 24 months ≥ 36 months n n n n n n Sliding 2 nails Yes 2 nails 23 22 6 8 5 5 No 2 nails 2 2 2 2 2 0 Total bone 25 24 8 10 7 5 Results far reaching to the time of ≥ 12 months has 4/35 cases where 2 nails are not able to slip according to bone growth. Reaching time ≥ 24 months, there are 4/31 cases where 2 nails are not able to slip with bone growth. Reaching time ≥ 36 months, there are 2/13 cases where 2 nails are not able to slip according to bone growth. Table 3.45. Results of evaluation of postoperative mobility at the time of re-examination ≥ 12, ≥ 24, ≥ 36 months (n: Number of patients) Mobilisation Preoperative (n=33) ≥ 12 months (n=24) ≥ 24 months (n=24) ≥ 36 months (n=17) n (%) n (%) n (%) n (%) Independent sitting 13(39,4) 1(4,2) 0(0,0) 0(0,0) Crawling/bottom shuffling 17(51,5) 4(16,7) 3(12,5) 4(23,5) Independent stand 1(3,0) 0(0,0) 0(0.0) 0(0,0) Assisted sit 0(0,0) 4(16,7) 1(4,2) 0(0,0) Independent walk 1(3,0) 12(50,0) 12(50,00) 5(29,4) Assisted walk 1(3,0) 3(20,8) 8(33,3) 8(47,1) Total 33 24 24 17 Results up to the point of ≥ 12 months, the level of improvement of movement increased significantly, the amount of travel in which the travel supported 3/24 cases (20.83%). Independent travel for 12/24 cases (50%). At time of ≥ 24 months, the level of movement increased but not significantly. At time of ≥ 36 months, there was a decrease in ability of movement and going independently reduced to 5/17 cases. 3.2.3. Surgical results according to the El Sobk scoring system Table 3.46. Evaluate surgical results according to El Sobk's scoring system at the time of follow-up examination ≥ 6, ≥ 24, ≥ 36 months (n: Number of patients) Level ≥ 6 months (n=28) ≥ 12 months (n=24) ≥ 24 months (n=24) ≥ 36 months (n=17) Patients Rate % Patients Rate % Patients Rate % Patients Rate % Excellent 27 96,4 18 75,0 18 75,0 14 82,4 Good 1 3,6 4 16,7 5 20,8 2 11,8 Average 0 0,0 2 8,3 1 4,2 1 5,8 Poor 0 0,0 0,0 0,0 0 0,0 0 0,0 Total 28 100 24 100 24 100 17 100 After ≥ 6 months, excellent 96.4%. Good and excellent after ≥ 1 year, ≥ 2 years and ≥ 3 years are all over 90%. Average of 2 cases Table 3.47. Assessment of patient satisfaction on criteria of travel, self-care, living, pain / discomfort, anxiety over time of follow up Criteria Preoperative (1) ≥ 6 months (2) ≥ 12 months (3) ≥ 24 months (4) p X ± SD X ± SD X ± SD X ± SD Independent walk 1,5±0,1 2,9±0,3 3,2±0,4 3,7±0,3 p(1,2) = 0,001 p(1,3) = 0,00 p(1,4) = 0,00 Self care 1,6±0,2 2,6±0,2 2,4±0,2 3,7±0,2 p(1,2) = 0,000 p(1,3) = 0,001 p(1,4) = 0,00 Living 1,6±0,2 2,1±0,3 2,9±0,3 3,3±0,1 p(1,2) = 0,014 p(1,3) = 0,00 p(1,4) = 0,00 Pain / Discomfort 2,6±0,1 3,6±0,1 5,0±0,0 5,0±0,0 p(1,2) = 0,00 p(1,3) = 0,00 p(1,4) = 0,00 Worry 1,8±0,2 3,6±0,1 5,0±0,0 5,0±0,0 p(1,2) = 0,000 p(1,3) = 0,00 p(1,4) = 0,00 All indicators to assess the level of patient satisfaction including: Walking, self-care, living, pain / discomfort, anxiety increased, statistically significant. Chapter 4. DISCUSSION 4.1. Clinical features and X-ray images of long bones, skull, spine, blood biochemical tests and electrolytes in patients with Osteogenesis imperfecta. 4.1.1. Age and gender characteristics According to table 3.2. The age group of surgery is mainly in the developing age group, accounting for the most, from the age of 10 - <18, the male / female ratio: 0.9 / 1. In our study, there was 1 patient of 2 years old, we chose the patient of 2 years of age or older because this age children often suffer many fractures due to children being more active at 2 years of age and older patients ≥ At the age of 18 years (1 patient 19 years and 1 patient 23 years), we still use the method of closing 2 intramedullary nails against the goal to stabilize the plan. 4.2. Evaluate the results of internal bone using self-made kits to treat deformation of lower limb bone in patients with imperfect bone formation 4.2.1. Evaluate the results near + Evaluation of postoperative results Evaluation after surgery at the time of re-examination: ≥ 1 month, ≥ 3 months, ≥ 6 months after surgery According to Table 3.35, after 1 month there were 47/49 cases of level 1 osteosarcoma (95.9%), there were 2/49 cases of no fracture accounted for 4.08%. According to Table 3.36 and Table 3.37, we found that, after 1 month of surgery, most axes were straight axes with 49/49 bone positions. After 3 months of monitoring 47 bone positions and after 6 months of 45 bone positions, the cases were straight and there were no cases of bent nails, bone protruding nails and screw splints. According to Table 3.38, the 3rd month onwards had a 2-slipped slip relative to bone growth. Prove that 2 nails have the ability to slip with bone growth. According to Table 3.39, one month after surgery, the ability of the patient's motor decreased due to the fact that the body did not have strong bone after 1 month of surgery. There was a significant improvement in motor skills in patients 3 - 6 months after surgery compared to before surgery. 4.2.2. Evaluating distal results after chiropractic surgery (after ≥ 12 months). According to Table 3.40. Shows that the shortest follow-up time ≥ 24 months (24 patients) accounts for 72.7%, the time to follow-up results is ≥ 36 months (17 patients) accounts for 51.5%, the follow-up time average far in study reaches 32.5 months. Due to the time frame for collecting data, patients who had surgery in the late stage of remote monitoring did not reach the time of ≥ 12 months, ≥ 24 months and ≥ 36 months after surgery. According to Table 3.41, it is shown that when the distance test results reach ≥ 12 months of follow-up, there are 44 bone positions, the cases are monitored vertically. At the time of ≥ 24 months, there were 6/39 cases with bone curvature but the level of deformation assessment was not enough to be re-operated because the recurrence level did not affect the patient's walking ability. Patients can still walk). Therefore, we do not intervene surgery when the patient is still able to walk. Up to ≥ 36 months of follow-up of 20 bone positions with up to 5 cases of axial curvature (4 cases using 1 nail, 1 case 2 nails) were the cases that detected the previous bone curvature but the degree of much increased. Thereby, we found that cases of recurrent deformation often occur in fixation bone patients equal to 1 intramedullary nail and 2 intramedullary nails but nails are not able to slip along with bone growth. According to Table 3.42, it is shown that when checking the far reaches of ≥ 12 months tracking 44 locations, the cases are monitored without complications of intramedullary nail, 1 case of screw splinting in this case. Do not have surgery to remove the screw. By the time of ≥ 24 months and ≥ 36 months, there were 5 cases of nail sticking out of the bone shell: 4 cases with 1 nail and 1 bone with 2 nails but not enough to have to have the surgery again. According to table 3.43. We checked that the results reached ≥ 12 months with 4/35 cases 2 nails are not able to slip according to bone growth. Reaching time ≥ 24 months, there are 4/31 cases where 2 nails are not able to slip with bone growth. Up to time ≥ 36 months with 2/13 cases 2 nails are not able to slip with bone development (2 cases 2 nails do not slip at the time of ≥ 12 and ≥ 24 months, 2 cases do not follow up). According to table 3.45. Checking the far reaches to ≥ 12 months, the level of improvement of movement increased significantly, the number of walking including 3/24 patients (20.83%). Traveling independently 12/24 patients (50%). At time of ≥ 24 months, the level of movement increased but not significantly. Up to ≥ 36 months, there was a decrease in mobility and independent walking reduced to 5/17 patients were monitored because the reason could be explained by the curved deformation of the lower limb bone that had not been operated. According to table 3.46. After ≥ 6 months, achieving excellent level on the El Sobk scale, accounting for 96.4%. Good and excellent surgery results after ≥ 1 year, ≥ 2 years and ≥ 3 years are over 90%. The average result only encountered 2 cases with very severe deformation (curved deformation) in both upper limbs. We achieved the above results because patients in the study mainly used the method of multiple osteotomy and alignment by 2 intramedullary nails. CONCLUSION Through research and treatment of 42 patients with Osteogenesis imperfecta at Military Hospital 7A Military Region 7 from January 2012 to December 2016, we would like to draw the following conclusions: 1. Clinical features and X-ray images of long bones, skulls, spine, blood biochemical tests and electrolytes in patients with Osteogenesis imperfecta. * Clinical characteristics: - Age of patients from 2-30 years, the average is 11.6 ± 6.1. The male / female ratio is: 1.33 / 1, there are 11 patients in the family suffering from OI. All patients had a history of fractures and fractures many times. The deformed deformity is mainly found in the thighs and lower legs, causing a serious impact on mobility and self-activity, accounting for 61.9-83.3%. Blue sclerae accounts for 88%. Creation of dentinogenesis imperfect teeth makes up 61.9%. Normal hearing. Scoliosis accounts for 35.7%. Chicken breast protruding accounts for 21.4%. Exercise: Sit still (31%) or move by crawling or puffing your butt (57.1%). * X-ray features: - The major deformed curvature in long bones of lower limb is 61.9% - 83.3%. Calcification of popcorn only occurs in the and dense metaphyseal lines is mainly found on the bones of the femur and tibia in patients treated with Bisphotphonate. Mostly, scoliosis occurs, in types of 16/42 patients (38.1%). Many images of skull bones 7/42 patients (16.67%). * Characteristics of blood biochemical and electrolyte test results: - Glucose, SGOT, SGPT, Creatinine, Urea, Ca +, and total calcium are within normal limits. 2. Evaluation of internal bone results using self-made kits for deformation of the lower limb bone in patients with imperfect bone formation in Military Hospital 7 A. Multiple osteotomy and fixtion bone surgery with 2 intramedullary with self-created kits to correct deformation of the lower limb bone and prevent recurrent fractures to help patients improve motor function and integrate into the community. The results are as follows: - Axial of limb: With 53 surgical bone positions, after 44 months of follow-up, 44 bone positions were straight. After ≥ 24 months, there are 6/39 bone curvature positions, but the degree of deformation assessment is not enough to be re-operated because the patient is still able to walk. After ≥ 36 months, there were 5/20 cases of pre-existing bent bones, the level did not increase much. - No recorded cases of bone fractures. - There are 2 cases of multiple osteotomy and fixtion bone that have fake joints; The remaining 51 cases were good callus formation - Instrument alignment: In 53 positions that fixtion bone, after ≥ 12 months, 44 locations without c