Acetabulum ; injuries ; surgery ; Fractures, Bone ; surgery ; Humans

Acetabulum ; surgery ; Arthroplasty, Replacement, Hip ; Femur ; surgery ; Humans ; Reoperation

OBJECTIVETo explore morphological character and clinical significance of superior-posterior acetabular wall by anatomically measuring and quantitatively analyzing thickness of posterior acetabular wall, then provide a theoretical reference for clinical treatment of acetabular fracture.

METHODSFifteen adult formalin-preserved cadaveric pelvises (8 males and 7 females) were used for this investigation. Excess soft tissue was removed and the whole acetabular posterior walls were marked with "angle" sector method and the thickness was measured with caliper in different levels of the different split points. The measurement results were validated and analyzed statistically.

RESULTSAt 5 mm away from acetabular rim, the average thickness of superior-posterior acetablar wall fluctuated between (6.47±0.61) mm and (7.43±0.71) mm; the average thickness of inferior-posterior acetabuluar wall fluctuated between (5.62±0.51) mm and (6.33±0.61) mm; the average thickness of acetabular roof fluctuated between (7.71±0.74) mm and (8.27±0.99) mm. There was no statistical difference between average thickness of superior-posterior wall of acetabulum and inferior-posterior wall of acetabulum (P>0.05), but the average thickness of acetabular roof was significantly larger than superior-posterior acetabular wall (P<0.05). At 10 mm away from the acetabular rim, the average thickness of superior-posterior acetabular wall fluctuated between (8.81±0.67) mm and (13.35±0.89)mm; the average thickness of inferior-posterior acetabular wall fluctuated between (7.02±0.63) mm and (7.66±0.69) mm; the average thickness of acetabular roof fluctuated between (14.46±0.97) mm and (17.05±1.35) mm. Comparatively, the average thickness of superior-posterior acetabular wall was significantly larger than inferior-posterior wall of acetabulum (P<0.05), and the average thickness of acetabular roof was significantly larger than superior-posterior acetabular wall (P<0.01). At 15 mm away from the acetabular rim, the average thickness of superior-posterior acetabular wall fluctuated between (12.08±0.78) mm and (19.84±1.03) mm; the average thickness of inferior-posterior acetabular wall fluctuated between (10.17±0.76) mm and (11.12± 0.77) mm; the average thickness of acetabular roof fluctuated between (23.23±1.12) mm and (26.01±1.53) mm. Comparatively, the average thickness of superior-posterior wall of acetabulum was significantly larger than inferior-posterior acetabular wall (P<0.01), and the average thickness of acetabular roof was significantly larger than superior-posterior acetabular wall (P< 0.01).

CONCLUSIONThe thickness of entire acetabular posterior edge revealed an increasing tendency from inferior-posterior wall to the superior-posterior wall to acetabular roof. And this trend became more obvious with increasing distance away from acetabular rim. Therefore, the superior-posterior acetabular wall could not only maintain the stability of hip joint but also bear loading.

Acetabulum ; anatomy & histology ; injuries ; surgery ; Female ; Humans ; Male

The hip with distinctive anatomical structure and complicated function plays an important role in normal standing and activity. The clinical doctors have paid attention to studies on hip biomechanics of normal structure and reconstruction. It was difficult for us to analyze hip in vivo because of its complex structure. Many examinations were preformed on animal models, but the reliability of results was unavoidably affected. Technology of finite-element analysis as one of the main methods of mechanics had been successfully applied in many fields, especially in analyzing on irregular bodies. The application in the field of orthopaedic surgery, for example the optimal design for prosthesis, stress analysis of grafts etc, had made great progress. The method could help us to improve current thoughts on study of biomechanics and make continuous advance in the future.
Acetabulum ; surgery ; Finite Element Analysis ; Hip Prosthesis ; Humans

Humans ; Acetabulum/surgery* ; Fractures, Compression ; Osteotomy ; Spinal Nerve Roots ; Prisoners

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

Acetabular is an important human joint for weight bearing. Quadrilateral plate is a crucial structure of medial acetabulum with special morphology and important function. Quadrilateral plate fractures are common fracture in acetabulum. Quadrilateral plate fracture is hard to expose and reduction because it is in the medial of acetabulum. At the same time,the bone in the quadrilateral plate is not easy to fixed for thinning bones and adjacent to the articular cavity. The operator should know well about the anatomy and choose the suitable internal fixation. After quadrilateral plate fractures, the femur head maybe displace medially even break into pelvis. That make reduction and treatment always be a challenge. With different kinds of fractures,the efficacy of treatment is not the same. This paper intend to review the relation of anatomic features,approaches, internal fixations, key point of treatment and efficacy.
Acetabulum ; injuries ; surgery ; Animals ; Fracture Fixation, Internal ; instrumentation ; methods ; trends ; Fractures, Bone ; surgery ; Humans

BACKGROUNDSevere acetabular bone deficiency is a major challenge in acetabular revision surgery. Most cases require reconstruction of the acetabulum with bone grafting and a reinforcement device. The purpose of this study was to evaluate the results of this procedure for severe acetabular bone deficiency in acetabular revision surgery.

METHODSThis study involved 12 patients (2 males and 10 females) with severe acetabular bone defects who underwent implantation of a reinforcement device (ring or cage) and bone grafting between February 2003 and October 2008. Using the Paprosky classification, 2 cases were Paprosky IIC, 6 were IIIA, and 4 were IIIB. The mean age at the time of surgery was 63.0 years (range, 46 - 78 years). During revision surgery, a reinforcement ring was implanted in 6 patients, and a cage in 6 patients. The clinical and radiographic results were evaluated retrospectively. The mean duration of follow-up was 37 months (range, 9 - 71 months).

RESULTSThe average Harris Hip Score improved from 35.2 preoperatively to 82.9 at the time of the final follow-up visit. The results were excellent in 8 hips (66.7%), good in 2 (16.7%), and fair in 2 (16.7%). Osteolysis was found in 1 case, but did not worsen. Three patients had yellow wound effusion, with healing after administration of dressing changes, debridement, and antibiotics. Dislocation occurred in a 62-year-old woman. Closed reduction was performed, and dislocation did not recur. There was no evidence of intraoperative acetabular fracture, nerve injury, ectopic ossification, aseptic loosening, or infection.

CONCLUSIONReconstruction with a reinforcement device and bone grafting is an effective approach to the treatment of acetabular bone deficiency in acetabular revision surgery, given proper indications and technique.

Acetabulum ; surgery ; Aged ; Bone Transplantation ; methods ; Female ; Hip ; surgery ; Humans ; Male ; Middle Aged ; Reoperation ; methods

OBJECTIVETo explore the clinical effects and related factors of combined anterior and posterior surgeries in treatment of double column acetabular fracture.

METHODSFrom August 2007 to July 2009, 19 patients with double column acetabular fracture were treated. There were 13 males and 6 females, with a mean age of 39.6 years (ranged, 27 to 52 years). Among the patients, upper double column fracture was in 11 cases, lower double column fracture was in 8 cases and double column fracture involved sacroiliac joint in 1 case. The mean time from injury to operation was 5.8 days (ranged, 4 to 10 days). All patients were received combined anterior and posterior surgeries, reconstructed plate and fixed by screw.

RESULTSOne patient was death, other patients were followed up from 12 to 18 months (with a mean time of 13.6 months). According to Harris standard, 9 cases got excellent results, 7 good cases and 2 fair.

CONCLUSIONCombined anterior and posterior surgeries for double column acetabular fracture can get satisfactory effects.

Acetabulum ; injuries ; surgery ; Adult ; Female ; Fracture Fixation, Internal ; methods ; Fractures, Bone ; surgery ; Humans ; Male ; Middle Aged

OBJECTIVE: To investigate whether the anteversion angle of acetabular prosthesis can be evaluated on the anteroposterior X-ray film of common double hip joint. METHODS: Total 32 patients(41 hips) after total hip arthroplasty were selected, including 18 males and 14 females, aged(66.2±4.1) years. All patients completed the positive X-ray film of both hips and plain CT scan of pelvis after operation. Acetabular anteversion was measured by plain CT scan of pelvis, and measured by Saka and other measurement formulas on X-ray film. RESULTS: The acetabular anteversion measured by X-ray film was(16.2±5.0)° and that measured by CT was (31.8±9.7)°(P=0.00). In addition, there was a significant linear correlation between X-ray film and CT(Pearson correlation coefficient (r=0.84, P=0.00). CONCLUSION CT can accurately measure the acetabular anteversion, but it has obvious disadvantages, such as large radiation, high cost, phantom CT artifact and so on. Although Saka measurement formula can not directly obtain the accurate acetabular anteversion as CT measurement, it has a high correlation with the acetabular anteversion measured by CT. Therefore, the method proposed in this study can also preliminarily evaluate the acetabular anteversion.
Acetabulum/surgery* ; Arthroplasty, Replacement, Hip/methods* ; Female ; Hip Joint/surgery* ; Hip Prosthesis ; Humans ; Male ; Pelvis