Bone Neoplasms ; diagnosis ; surgery ; Humans ; Pelvic Bones

Bone Neoplasms ; surgery ; Humans ; Pelvic Bones

Emergency Treatment ; Fractures, Bone/surgery* ; Hemodynamics ; Humans ; Pelvic Bones/surgery*

PURPOSE: To develop a robot-arm type image-guided surgery system for percuatneous screw fixation of the sacro-iliac joint and to evaluate its accuracy. MATERIALS AND METHODS: We have developed an image-guided surgery system using a three-dimensional digitizer (Microscribe 3-D G2, Immersion, USA) and a personal computer. The registration error and target localization error at fiducial registration were measured 30 times for each using a phantom made with plastic pelvic bone model (Sawbones, USA). Sixteen 6.5 mm cannulated screws were inserted into four plastic bone models, and the accuracy was evaluated. RESULTS: The target localization error was 1.46+/-0.47 mm while the registration error was 0.73+/-0.23 mm. All of the 16 screws were inserted well across the sacro-iliac joint, and there was neither cortical breach nor collision between screws or washers. CONCLUSION: The accuracy of the developed system was similar to that of optical tracker-based navigation systems, and its helpfulness and usefulness was proven with simulation surgery using plastic bone models.
Immersion ; Joints* ; Microcomputers ; Pelvic Bones ; Plastics ; Surgery, Computer-Assisted*

Aged ; Hip Fractures/surgery* ; Humans ; Pelvic Bones ; Risk Factors

Fractures, Bone ; diagnosis ; diagnostic imaging ; surgery ; therapy ; Humans ; Pelvic Bones ; diagnostic imaging ; injuries ; surgery ; Radiography

BACKGROUNDGiven that three-dimensional finite element models have been successfully used to analyze biomechanics in orthopedics-related research, this study aimed to establish a finite element model of the pelvic bone and three-fin acetabular component and evaluate biomechanical changes in this model after implantation of a three-fin acetabular prosthesis in a superior segmental bone defect of the acetabulum.

METHODSIn this study, three-dimensional finite element models of the pelvic bone and three-fin acetabular component were first established. The prosthesis model was characterized by three different conformational fins to facilitate and optimize the prosthetic design. The spongy and cortical bones were evaluated using a different modulus of elasticity in this established model.

RESULTSThe maximum and minimum von Mises stresses on the fins of the acetabular component were 15.2 and 0.74, respectively. The maximum and minimum micromotion between the three-fin acetabular component and the acetabulum bone interface were 27 and 13 µm, respectively. A high primary stability and implied better clinical outcome were revealed.

CONCLUSIONFinite element analysis may be an optimal strategy for biomechanics-related research of prosthetic design for segmental acetabular bone defects.

Acetabulum ; surgery ; Finite Element Analysis ; Hip Prosthesis ; Humans ; Pelvic Bones ; surgery

Fracture Fixation ; methods ; trends ; Fractures, Bone ; surgery ; Humans ; Pelvic Bones ; injuries ; surgery

OBJECTIVETo investigate the clinical results of modified Sutherland pelvic osteotomy for developmental dysplasia of hip (DDH).

METHODSSutherland pelvic osteotomy were performed in 10 patients (11 hips) with DDH. Among them, there were 3 male (3 hips) and 7 female (8 hips) patients, aged (32 ± 8) years. During operation, arthroscopes were performed additionally to remove the existing hyperplasia tissue in the fossae ovalis and trimming acetabulum and glenoid labrum, thus to insure the better match between the femoral head and the realigned acetabulum. The change of imaging indexes were acquired by comparing the preoperative X-ray with the postoperative X-ray. The change of hip function and life quality were acknowledged according to contrast and analysis Harris hip score and Short Form 12-items Health Survey (SF-12) before and after osteotomy.

RESULTSAll patients were followed up for a mean of (5.2 ± 2.3) years, the osteotomy were all union in 3 months. The acetabular head index was 71 ± 8 before operation, and 86 ± 4 after operation. The pre- and post-operative centre edge angle were (7 ± 9)° and (33 ± 9)°, sharp angle were (48 ± 4)° and (37 ± 5)°, acetabular index angle were (24 ± 8)° and (11 ± 5)° respectively. The average Harris score improved from 42 ± 13 preoperatively to 90 ± 5 postoperatively, with 100% excellent and good results. Every domains of SF-12 was improved in the different extents postoperatively, the improvement of physical component summary was more conspicuous than mental component summary. The imaging indexes, Harris and SF-12 were all improved with significant difference (all P < 0.05).

CONCLUSIONSThe modified Sutherland pelvic osteotomy is effective. It could increase the load bearing capacity of hip, and improve the quality of life.

Adult ; Arthroscopy ; Female ; Hip Dislocation, Congenital ; surgery ; Humans ; Male ; Osteotomy ; methods ; Pelvic Bones ; surgery ; Treatment Outcome

Fractures, Bone ; complications ; diagnosis ; surgery ; therapy ; Humans ; Pelvic Bones ; injuries ; surgery ; Time Factors