To contrast the methodology of measuring cup placement precision utilizing Mimics and Matlab programming, based on clinical CT images of primary THA cases with computer assisted navigated surgery (CANS) and with the traditional manual method (MANS). The method was applied and analyzed to measure cup anteversion, cup abduction of 50 clinical cases with CANS and MANSThe results show that, cup placement precision differences exits between primary THA cases with CANS and MANS; more cases with CANS are within the safe zone contrasting MANS, and there was less variation and less placement error in CANS cases. CANS can improve cup placement precision and reduce the chance of dislocation efficiently.
Arthroplasty, Replacement, Hip ; instrumentation ; methods ; Humans ; Surgery, Computer-Assisted ; methods

Orthopaedic implant technology is heavily based on the development and use of biomaterials. These are non-living materials (e.g. metals, polymers and ceramics) that are introduced into the human body as constituents of implants that fulfill or replace some important function. Examples would be prosthetic joint replacements and fracture fixation implants. For orthopaedic biomaterials to succeed in their desired functions and outcomes in the body, a number of factors need to be considered. The most obvious mechanical properties of the implants are that they need to suit their intended function, and various classes and types of biomaterials have been developed and characterised for use in different implant components depending on their demands. Less well understood but no less important are the interactions that occur between the constituent biomaterials and the living cells and tissues, both of the human host as well as pathogens such as bacteria. Biomaterials used for orthopaedic applications are generally considered to be biocompatible. However, adverse effects arising from interactions at the implant interface can result in various modes of implant failure, such as aseptic loosening and implant infection. This review paper uses the illustrative example of total hip replacement (which has been called the operation of the century) to highlight key points in the evolution of orthopaedic biomaterials. It will also examine research strategies that seek to address some of the major problems that orthopaedic implant surgery are facing today.
Absorbable Implants ; Arthroplasty, Replacement, Hip ; instrumentation ; methods ; Biocompatible Materials ; Humans ; Orthopedic Procedures ; instrumentation ; methods ; trends ; Osteoblasts

Arthroplasty, Replacement, Hip ; Fracture Fixation, Internal ; Hip Fractures ; surgery ; Humans ; Precision Medicine ; instrumentation ; methods ; Preoperative Period

Various systems of computer-assisted orthopaedic surgery (CAOS) in total hip arthroplasty (THA) were reviewed. The first clinically applied system was an active robotic system (ROBODOC), which performed femoral implant cavity preparation as programmed preoperatively. Several reports on cementless THA with ROBODOC showed better stem alignment and less variance in limb-length inequality on radiographic evaluation, less incidence of pulmonary embolic events on transesophageal cardioechogram, and less stress shielding on the dual energy X-ray absorptiometry analysis than conventional manual methods. On the other hand, some studies raise issues with active systems, including a steep learning curve, muscle and nerve damage, and technical complications, such as a procedure stop due to a bone motion during cutting, requiring re-registration and registration failure. Semi-active robotic systems, such as Acrobot and Rio, were developed for ease of surgeon acceptance. The drill bit at the tip of the robotic arm is moved by a surgeon's hand, but it does not move outside of a milling path boundary, which is defined according to three-dimensional (3D) image-based preoperative planning. However, there are still few reports on THA with these semi-active systems. Thanks to the advancements in 3D sensor technology, navigation systems were developed. Navigation is a passive system, which does not perform any actions on patients. It only provides information and guidance to the surgeon who still uses conventional tools to perform the surgery. There are three types of navigation: computed tomography (CT)-based navigation, imageless navigation, and fluoro-navigation. CT-based navigation is the most accurate, but the preoperative planning on CT images takes time that increases cost and radiation exposure. Imageless navigation does not use CT images, but its accuracy depends on the technique of landmark pointing, and it does not take into account the individual uniqueness of the anatomy. Fluoroscopic navigation is good for trauma and spine surgeries, but its benefits are limited in the hip and knee reconstruction surgeries. Several studies have shown that the cup alignment with navigation is more precise than that of the conventional mechanical instruments, and that it is useful for optimizing limb length, range of motion, and stability. Recently, patient specific templates, based on CT images, have attracted attention and some early reports on cup placement, and resurfacing showed improved accuracy of the procedures. These various CAOS systems have pros and cons. Nonetheless, CAOS is a useful tool to help surgeons perform accurately what surgeons want to do in order to better achieve their clinical objectives. Thus, it is important that the surgeon fully understands what he or she should be trying to achieve in THA for each patient.
Arthroplasty, Replacement, Hip/instrumentation/*methods ; Humans ; *Robotics ; Stereotaxic Techniques ; *Surgery, Computer-Assisted

OBJECTIVETo evaluate the effect of cemented long stem bipolar prosthetic prosthesis in the management of unstable intertrochanteric fractures in the elderly.

METHODSA retrospective analysis of 23 elderly cases of uncemented long-stem prosthetic replacement for unstable intertrochanteric fractures was conducted. Of the 23 elderly patients, 6 had type IIA fracture by Evans-Jenson classification, 11 had type IIB fractures, and 6 had type III fractures.

RESULTSOne patient died due to severe respiratory failure during the follow-up period. The patients were followed up for 6 to 10 months (mean 15 months), and no dislocation, infection, loosening or sinking of the prosthesis was found in the followed-up cases with a Harris score reaching 84.8.

CONCLUSIONCemented long-stem bipolar prosthetic prosthesis replacement is effective for management of unstable intertrochanteric fractures in the elderly.

Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Hip ; instrumentation ; methods ; Female ; Hip Fractures ; surgery ; Hip Prosthesis ; Humans ; Male ; Retrospective Studies ; Treatment Outcome

OBJECTIVETo determine the clinical outcomes of two-staged cementless revision arthroplasty for the treatment of deep periprosthetic infection after total hip arthroplasty.

METHODSTwenty-three patients with deep periprosthetic infection treated with a standard protocol of two-staged cementless revision hip arthroplasty were enrolled in this study. There were 9 male patients and 14 female patients with an average age of 64 years (range, 52-78 years). In all cases, antibiotics-loaded cement spacers were implanted after removal of all the prosthetic components and thorough debridements had been done. All patients had a minimum of 2 weeks of intravenous antibiotics followed by 4 weeks of oral antibiotics after implant removal. After a mean interval of 6.7 months (3-28 months), revision arthroplasties were carried out with cementless femoral components followed by 2 weeks of intravenous antibiotics and 4 weeks of oral antibiotics.

RESULTSThe mean follow-up period was (4.3±3.5) years. There were 2 cases of recurrent infections in this study. Intraoperative periprosthetic fractures were observed in 3 patients. One patient had dislocation of the implanted spacer during the interval period and 2 patients had hip dislocation after reimplantation. Mild subsidence of femoral component occurred in 1 patient. There were no cases of loosening of femoral components and cementless acetabular components in patients without infection recurrence. The Harris hip score increased from a preoperative mean of 36±13 to 85±13 at 12 months after reimplantation.

CONCLUSIONSUsing cementless prostheses in two-staged revisions of hip periprosthetic infections can provide low rate of infection recurrence and good implant stability, but cautions must be taken when treating patients with infection caused by multidrug-resistant organisms.

Aged ; Anti-Bacterial Agents ; administration & dosage ; Arthroplasty, Replacement, Hip ; instrumentation ; methods ; Female ; Follow-Up Studies ; Hip Prosthesis ; Humans ; Male ; Middle Aged ; Prosthesis-Related Infections ; surgery ; Retrospective Studies

BACKGROUND: Total hip arthroplasty (THA) for severe developmental dysplasia of the hip (DDH) is a technically demanding procedure for arthroplasty surgeons, and it is often difficult to reduce the hip joint without soft tissue release due to severe flexion contracture. We performed two-stage THAs in irreducible hips with expected lengthening of the affected limb after THA of over 2.5 cm or with flexion contractures of greater than 30 degrees in order to place the acetabular cup in the true acetabulum and to prevent neurologic deficits associated with acute elongation of the limb. The purpose of this study is to evaluate the outcomes of cementless THA in patients with severe DDH with a special focus on the results of two-stage THA. METHODS: Retrospective clinical and radiological evaluations were done on 17 patients with Crowe type III or IV developmental DDH treated by THA. There were 14 women and 3 men with a mean age of 52.3 years. Follow-ups averaged 52 months. Six cases were treated with two-stage THA followed by surgical hip liberalization and skeletal traction for 2 weeks. RESULTS: The mean Harris hip score improved from 40.9 to 89.1, and mean leg length discrepancy (LLD) in 13 unilateral cases was reduced from 2.95 to 0.8 cm. In the patients who underwent two-stage surgery, no nerve palsy was observed, and the single one-stage patient with incomplete peroneal nerve palsy recovered fully 4 weeks postoperatively. CONCLUSIONS: The short-term clinical and radiographic outcomes of primary cementless THA for patients with Crowe type III or IV DDH were encouraging. Two-stage THA followed by skeletal traction after soft tissue release could provide alternative solutions to the minimization of limb shortenings or LLD without neurologic deficits in highly selected patients.
Adult ; Aged ; Arthroplasty, Replacement, Hip/*instrumentation/*methods ; Female ; Femur/radiography/surgery ; Hip/radiography/surgery ; Hip Dislocation, Congenital/pathology/radiography/*surgery ; Hip Joint/pathology/radiography/surgery ; Hip Prosthesis ; Humans ; Ilium/radiography/surgery ; Male ; Middle Aged ; Orthopedic Fixation Devices ; Retrospective Studies ; Traction

Despite advances in surgical techniques and instrumentation, current intra-operative estimations of acetabular version in total hip arthroplasty are of limited accuracy. In the present study, two experienced orthopedic surgeons compared intra-operatively measured (using portable imaging) anteversions and vertical inclinations of acetabular components with those measured using standardized radiographs post-operatively in 40 patients. Of the all vertical inclinations measured from intra-operative radiographs, 72.5% (n=29) were within +/-2degrees, and 97.5% (n=39) were within +/-5degrees of those determined using post-operative radiographs, and for anteversion, 52.5% (n=21) were within +/-2degrees, and 97.5% (n=39) were within +/-5degrees. Post-operative radiographs demonstrated that 90.0% (n=36) of vertical inclinations and anteversions were within the adequate zone. Obviously, our method has its limitations, but the authors conclude that the method described in this article better allows surgeons to verify acetabular version intra-operatively. In particular, the described method is suitable in cases with a deformed acetabular anatomy and difficult revision surgery.
Acetabulum/radiography/*surgery ; Adult ; Aged ; Aged, 80 and over ; *Arthroplasty, Replacement, Hip ; Female ; Hip Joint/*radiography/surgery ; Hip Prosthesis ; Humans ; Imaging, Three-Dimensional/methods ; Intraoperative Care/*instrumentation/methods ; Male ; Middle Aged ; Prosthesis Fitting

PURPOSE: We evaluated the results of more than 10 years of follow-up of total hip arthroplasty using a second-generation cementless femoral prosthesis with a collar and straight distal fixation channels. MATERIALS AND METHODS: One hundred five patients (129 hips) who underwent surgery between 1991 and 1996 for primary total hip arthroplasty using cementless straight distal fluted femoral stems were followed for more than 10 years. Ninety-four hips in 80 patients were available for clinical and radiologic analysis. The mean age at the time of surgery was 47 years, and the mean duration of follow-up was 14.3 years. RESULTS: The mean Harris hip scores had improved from 58 points to 88 points at the time of the 10-year follow-up. Activity-related thigh pain was reported in nine hips (10%). At the last follow-up, 93 stems (99%) were biologically stable and one stem (1%) was revised because of loosening. No hip had distal diaphyseal osteolysis. Proximal femoral stress-shielding was reported in 86 hips (91%). We found no significant relationship between collar-calcar contact and thigh pain, stem fixation status, or stress-shielding. The cumulative survival of the femoral stem was 99% (95% confidence interval, 98-100%) after 10 years. CONCLUSION: The long-term results of total hip arthroplasty using a second-generation cementless femoral prosthesis with a collar and straight distal fixation channels were satisfactory; however, the high rate of proximal stress-shielding and the minimal effect of the collar indicate the need for some changes in the stem design.
Adult ; Aged ; Arthroplasty, Replacement, Hip/*instrumentation/*methods ; Bone Cements ; Female ; Femoral Neck Fractures/radiography/*surgery ; Femur Head Necrosis/radiography/*surgery ; Follow-Up Studies ; *Hip Prosthesis ; Humans ; Male ; Middle Aged ; Osteoarthritis, Hip/radiography/*surgery ; Time Factors ; Treatment Outcome

BACKGROUND: This study examines the clinical and radiologic results of ceramic-on-ceramic total hip arthroplasties with regard to wear, osteolysis, and fracture of the ceramic after a minimum follow-up of six years. METHODS: We evaluated the results of a consecutive series of 148 primary ceramic-on-ceramic total hip arthroplasties that had been performed between May 2001 and October 2005 in 142 patients. The mean age was 57.2 years (range, 23 to 81 years). The mean follow-up period was 7.8 years (range, 6.1 to 10.1 years). Preoperative diagnosis was avascular necrosis in 77 hips (52%), degenerative arthritis in 36 hips (24.3%), femur neck fracture in 18 hips (12.2%), rheumatoid arthritis in 15 hips (10.1%), and septic hip sequelae in 2 hips (1.4%). Clinical results were evaluated with the Harris hip score, and the presence of postoperative groin or thigh pain. Radiologic analysis was done with special attention in terms of wear, periprosthetic osteolysis, and ceramic failures. RESULTS: The mean Harris hip score improved from 58.3 (range, 10 to 73) to 92.5 (range, 79 to 100) on the latest follow-up evaluation. At final follow-up, groin pain was found in 4 hips (2.7%), and thigh pain was found in 6 hips (4.1%). Radiologically, all femoral stems demonstrated stable fixations without loosening. Radiolucent lines were observed around the stem in 25 hips (16.9%), and around the cup in 4 hips (2.7%). Endosteal new bone formation was observed around the stem in 95 hips (64.2%) and around the cup in 88 hips (59.5%). No osteolysis was observed around the stem and cup. There were 2 hips (1.4%) of inclination changes of acetabular cup, 2 hips (1.4%) of hip dislocation, 1 hip (0.7%) of ceramic head fracture, and 1 hip (0.7%) of squeaking. The Kaplan-Meier survival rate of the prostheses was 98.1% at postoperative 7.8 years. CONCLUSIONS: The ceramic-on-ceramic total hip arthroplasty produced excellent clinical results and implant survival rates with no detectable osteolysis on a minimum six-year follow-up study. The ceramic-on-ceramic couplings could be a reasonable option of primary total hip arthroplasty for variable indications.
Adult ; Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Hip/adverse effects/instrumentation/*methods ; *Ceramics ; Female ; Follow-Up Studies ; Hip Joint/radiography/surgery ; *Hip Prosthesis ; Humans ; Kaplan-Meier Estimate ; Male ; Middle Aged ; Pain, Postoperative/etiology ; Prosthesis Failure ; Range of Motion, Articular