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Sample records for acetabular dysplasia cup

  1. Acetabular Cup Revision.

    PubMed

    Kim, Young-Ho

    2017-09-01

    The use of acetabular cup revision arthroplasty is on the rise as demands for total hip arthroplasty, improved life expectancies, and the need for individual activity increase. For an acetabular cup revision to be successful, the cup should gain stable fixation within the remaining supportive bone of the acetabulum. Since the patient's remaining supportive acetabular bone stock plays an important role in the success of revision, accurate classification of the degree of acetabular bone defect is necessary. The Paprosky classification system is most commonly used when determining the location and degree of acetabular bone loss. Common treatment options include: acetabular liner exchange, high hip center, oblong cup, trabecular metal cup with augment, bipolar cup, bulk structural graft, cemented cup, uncemented cup including jumbo cup, acetabular reinforcement device (cage), trabecular metal cup cage. The optimal treatment option is dependent upon the degree of the discontinuity, the amount of available bone stock and the likelihood of achieving stable fixation upon supportive host bone. To achieve successful acetabular cup revision, accurate evaluation of bone defect preoperatively and intraoperatively, proper choice of method of acetabular revision according to the evaluation of acetabular bone deficiency, proper technique to get primary stability of implant such as precise grafting technique, and stable fixation of implant are mandatory.

  2. A tribological study of UHMWPE acetabular cups and polyurethane compliant layer acetabular cups.

    PubMed

    Smith, S L; Ash, H E; Unsworth, A

    2000-01-01

    A novel design of polyurethane compliant layer acetabular cup has been developed through a series of friction, creep and wear tests. Friction tests were initially conducted on ABG standard form, polyurethane acetabular cups and an ABG standard form, UHMWPE acetabular cup for comparison. The polyurethane cups showed lower friction than the UHMWPE cup with maximum friction factors between 0. 008 and 0.02 compared with 0.035 for the UHMWPE cup. This indicated that, in the polyurethane cups, more of the load across the joint was carried by the fluid entrapped in the joint space rather than with asperity contact, compared with the UHMWPE cup. The inherent compliance of the polyurethane is used to promote elasto-hydrodynamic lubrication. However, this compliance raised concerns over excessive creep, which may in turn adversely affect tribological performance. Therefore, creep tests were undertaken on the ABG standard form, polyurethane acetabular cups followed by further friction tests. Small amounts of creep occurred in the polyurethane cups at ambient temperature, which reduced the friction slightly (maximum friction factors of 0.009) due to increased conformity between the head and the cup. However, at 37 degrees C, greater creep occurred causing pinching of the femoral head by the acetabular cup resulting in lubricant starvation and higher friction (maximum friction factors of 0.035). The design of the polyurethane cups was subsequently modified to incorporate a flared rim to eliminate the possibility of fluid starvation through pinching. Creep in polyurethane acetabular cups is also affected by the method of fixation of the cups, due to the conformity with and the stiffness of the cup backing. Hence, a one-million-cycle wear test was performed on five ABG flared form, polyurethane acetabular cups on the Mk. I Durham Hip Joint Wear Simulator to evaluate the best method of fixation for the polyurethane cups. The smallest amount of penetration, due to creep and wear

  3. Syndrome of symptomatic adult acetabular dysplasia (SAAD syndrome)

    PubMed Central

    Birrell, F; Silman, A; Croft, P; Cooper, C; Hosie, G; Macfarlane, G

    2003-01-01

    Design: Cross sectional analysis of a prospective cohort. Setting: 35 general practices across the UK. Subjects: 195 patients (63 male, 132 female) aged 40 years and over presenting with a new episode of hip pain Results: The prevalence of acetabular dysplasia in this study of new presenters with hip pain was high (32%). There was no significant relationship between acetabular dysplasia and radiographic OA overall. Conclusions: The high prevalence of acetabular dysplasia across all grades of OA severity suggests that dysplasia itself may be an important cause of hip pain ("symptomatic adult acetabular dysplasia"). PMID:12634238

  4. Analysis of version in the acetabular cup.

    PubMed

    Seradge, H; Nagle, K R; Miller, R J

    1982-06-01

    To determine the amount of anteversion or retroversion of the acetabular component of the implanted total hip prosthesis, two anteroposterior radiographs of the hip are obtained, with the contralateral hip flexed to compensate for the possible existing flexion contracture. The X-ray beam is centered on the implanted total hip in one radiograph, and moved away from it toward the contralateral hip in the second radiograph. If the cup is anteverted, the opening will seem wider in the second radiograph. To calculate the angle, the location of the center of the X-ray beam on the X-ray plate must be know. The center of the X-ray beam can be marked on the radiograph by putting a metalic cross on the patient, over the centering cross of the X-ray light source. If the distance of the signature of the X-ray's center beam is less than 8 mm for the center of the cup on the X-ray film, the cup version can be calculated from the arcsin of the shortest to the largest diameter of the cup. If the central ray's signature is farther away, correction is necessary for this calculation. Also, the variable parameters, e.g., cup size, and magnification rate, should be considered in the calculations. The anteroposterior radiographs of the implanted total hip, obtained with the central beam being marked on the X-ray plate, not only are useful for evaluation of the implant but also can be used to calculate the version angle with an accuracy of +/-2 degrees. The necessary calculation is tabulated for cups with an outside diameter of 44-56 mm.

  5. Comparison of flanged and unflanged acetabular cup design

    PubMed Central

    2010-01-01

    Background and purpose Adequate depth of cement penetration and cement mantle thickness is important for the durability of cemented cups. A flanged cup, as opposed to unflanged, has been suggested to give a more uniform cement mantle and superior cement pressurization, thus improving the depth of cement penetration. This hypothesis was tested experimentally. Materials and methods The same cup design with and without flange (both without cement spacers) was investigated regarding intraacetabular pressure, cement mantle thickness, and depth of cement penetration. With machine control, the cups were inserted into open-pore ceramic acetabular models (10 flanged, 10 unflanged) and into paired cadaver acetabuli (10 flanged, 10 unflanged) with prior pressurization of the cement. Results No differences in intraacetabular pressures during cup insertion were found, but unflanged cups tended to migrate more towards the acetabular pole. Flanged cups resulted in thicker cement mantles because of less bottoming out, whereas no differences in cement penetration into the bone were observed. Interpretation Flanged cups do not generate higher cementation pressure or better cement penetration than unflanged cups. A possible advantage of the flange, however, may be to protect the cup from bottoming out, and there is possibly better closure of the periphery around the cup, sealing off the cement-bone interface. PMID:20860522

  6. Minimum Lateral Bone Coverage Required for Securing Fixation of Cementless Acetabular Components in Hip Dysplasia

    PubMed Central

    Nakashima, Yasuharu; Nakamura, Tetsuro; Ito, Yoshihiro; Hara, Toshihiko

    2017-01-01

    Objectives. To determine the minimum lateral bone coverage required for securing stable fixation of the porous-coated acetabular components (cups) in hip dysplasia. Methods. In total, 215 primary total hip arthroplasties in 199 patients were reviewed. The average follow-up period was 49 months (range: 24–77 months). The lateral bone coverage of the cups was assessed by determining the cup center-edge (cup-CE) angle and the bone coverage index (BCI) from anteroposterior pelvic radiographs. Further, cup fixation was determined using the modified DeLee and Charnley classification system. Results. All cups were judged to show stable fixation by bone ingrowth. The cup-CE angle was less than 0° in 7 hips (3.3%) and the minimum cup-CE angle was −9.2° (BCI: 48.8%). Thin radiolucent lines were observed in 5 hips (2.3%), which were not associated with decreased lateral bone coverage. Loosening, osteolysis, dislocation, or revision was not observed in any of the cases during the follow-up period. Conclusion. A cup-CE angle greater than −10° (BCI > 50%) was acceptable for stable bony fixation of the cup. Considering possible errors in manual implantation, we recommend that the cup position be planned such that the cup-CE angle is greater than 0° (BCI > 60%). PMID:28299327

  7. Three Patterns of Acetabular Deficiency Are Common in Young Adult Patients With Acetabular Dysplasia.

    PubMed

    Nepple, Jeffrey J; Wells, Joel; Ross, James R; Bedi, Asheesh; Schoenecker, Perry L; Clohisy, John C

    2017-04-01

    Detailed recognition of the three-dimensional (3-D) deformity in acetabular dysplasia is important to help guide correction at the time of reorientation during periacetabular osteotomy (PAO). Common plain radiographic parameters of acetabular dysplasia are limited in their ability to characterize acetabular deficiency precisely. The 3-D characterization of such deficiencies with low-dose CT may allow for more precise characterization. The purposes of this study were (1) to determine the variability in 3-D acetabular deficiency in acetabular dysplasia; (2) to define subtypes of acetabular dysplasia based on 3-D morphology; (3) to determine the correlation of plain radiographic parameters with 3-D morphology; and (4) to determine the association of acetabular dysplasia subtype with patient clinical characteristics including sex, range of motion, and femoral version. Using our hip preservation database, we identified 153 hips (148 patients) that underwent PAO from October 2013 to July 2015. Among those, we noted 103 hips in 100 patients with acetabular dysplasia (lateral center-edge angle < 20°) and who had a Tönnis grade of 0 or 1. Eighty-six patients (86%) underwent preoperative low-dose pelvic CT scans at our institution as part of the preoperative planning for PAO. It is currently our standard to obtain preoperative low-dose pelvic CT scans (0.75-1.25 mSv, equivalent to three to five AP pelvis radiographs) on all patients before undergoing PAO unless a prior CT scan was performed at an outside institution. Hips with a history of a neuromuscular disorder, prior trauma, prior surgery, radiographic evidence of joint degeneration, ischemic necrosis, or Perthes-like deformities were excluded. Fifty hips in 50 patients met inclusion criteria and had CT scans available for review. These low-dose CT scans of 50 patients with symptomatic acetabular dysplasia undergoing evaluation for surgical planning of PAO were then retrospectively studied. CT scans were analyzed

  8. Hemispheric cups do not reproduce acetabular rim morphology.

    PubMed

    Vandenbussche, Eric; Saffarini, Mohammed; Delogé, Nicolas; Moctezuma, José-Luis; Nogler, Michael

    2007-06-01

    Iliopsoas impingement is a recurrent complication following THA, caused by muscle friction against a protrusive prosthetic cup.This study was designed to quantify the dimensional variations in acetabular rim profiles, with particular regard to the iliopubic valley, in order to suggest means to prevent iliopsoas impingement. 34 cadaver pelvises were analyzed using a hip navigation system. The morphometric data were processed to plot profiles of all acetabular rims with particular regard to the shape and depth of the psoas valley. The acetabular rim is an asymmetric succession of 3 peaks and 3 troughs. The psoas valley is a salient feature in most pelvises and there is only a weak correlation between its depth (mean 3.8 mm, SD 2.0) and acetabular diameter, anteversion, or inclination. It would be difficult to obviate the anterior overlap of the acetabulum using a hemispheric cup, a fortiori in certain morphotypes, without compromising range of motion or risk of dislocation. The solution for prevention of iliopsoas impingement would be to adapt cup design to acetabular anatomy, which may require different implants for the right and left sides, and hence a doubled inventory.

  9. Navigated Acetabular Cup Fixation for Acetabular Deformity or Revision Total Hip Arthroplasty

    PubMed Central

    Yoon, Jung-Ro; Yu, Jung Jin; Seo, Hyo-Sung

    2014-01-01

    Purpose To evaluate the usefulness of navigated acetabular cup fixation for total hip arthroplasty in patients with acetabular deformity or revision total hip arthroplasty. Materials and Methods This study enrolled 28 patients with at least 12 months' follow-up. The safe zone of the acetabular cup was defined as 40°±10°in inclination and 15°±10°in anteversion. The authors used the navigation and radiographic data to determine whether the acetabular cup was located within the safe zone or not. To evaluate the clinical outcomes, preoperative and last follow-up Harris hip scores were checked, and the occurrence of complications was evaluated. Results According to the navigation data, the mean inclination and anteversion were 38.5°±4.7°(range, 32°-50°) and 16.6°±4.0°(range, 8°-23°), respectively. According to the radiographic data the mean inclination and anteversion were 40.5°±4.6°(range, 32°-50°) and 19.4°±4.2°(range, 8°-25°), respectively. In both cases, all values were within the safe zone. Harris hip score was improved in all patients from preoperative 52.3±14.4 points (range, 29-87 points) to 88.0±9.0 points (range, 65-99 points) at the last follow-up. There was no dislocation or loosening of both cases. Conclusion Navigated acetabular cup fixation is a useful technique for total hip arthroplasty in patients with acetabular deformity or revision total hip arthroplasty because it prevents the malposition and related complications. PMID:27536573

  10. A novel method to assess primary stability of press-fit acetabular cups.

    PubMed

    Crosnier, Emilie A; Keogh, Patrick S; Miles, Anthony W

    2014-11-01

    Initial stability is an essential prerequisite to achieve osseointegration of press-fit acetabular cups in total hip replacements. Most in vitro methods that assess cup stability do not reproduce physiological loading conditions and use simplified acetabular models with a spherical cavity. The aim of this study was to investigate the effect of bone density and acetabular geometry on cup stability using a novel method for measuring acetabular cup micromotion. A press-fit cup was inserted into Sawbones(®) foam blocks having different densities to simulate normal and osteoporotic bone variations and different acetabular geometries. The stability of the cup was assessed in two ways: (a) measurement of micromotion of the cup in 6 degrees of freedom under physiological loading and (b) uniaxial push-out tests. The results indicate that changes in bone substrate density and acetabular geometry affect the stability of press-fit acetabular cups. They also suggest that cups implanted into weaker, for example, osteoporotic, bone are subjected to higher levels of micromotion and are therefore more prone to loosening. The decrease in stability of the cup in the physiological model suggests that using simplified spherical cavities to model the acetabulum over-estimates the initial stability of press-fit cups. This novel testing method should provide the basis for a more representative protocol for future pre-clinical evaluation of new acetabular cup designs.

  11. Labral morphologic characteristics in patients with symptomatic acetabular dysplasia.

    PubMed

    Sankar, Wudbhav N; Beaulé, Paul E; Clohisy, John C; Kim, Young-jo; Millis, Michael B; Peters, Christopher L; Podeszwa, David A; Schoenecker, Perry L; Sierra, Rafael J; Sink, Ernest L; Sucato, Daniel J; Zaltz, Ira

    2015-09-01

    The morphologic characteristics of the labrum in patients with symptomatic acetabular dysplasia have been described to some extent in smaller retrospective series, but the need remains to further define these disease characteristics and their importance as a diagnostic feature of hip instability. To (1) characterize the morphologic characteristics of the labrum in patients with symptomatic acetabular dysplasia and (2) test the relationships between specific labral variants, severity of dysplasia, and duration of symptoms. Cross-sectional study; Level of evidence, 3. Thirteen surgeons from 10 centers enrolled patients undergoing periacetabular osteotomy (PAO) for symptomatic acetabular dysplasia from 2008 to 2014. Patient demographics, presenting characteristics, preoperative radiographic data, operative data, and intraoperative findings were prospectively collected and retrospectively reviewed. A total of 942 patients (972 hips) met the initial inclusion criteria, with a mean age of 25.2 years (range, 9-51 years; 84% female, 16% male). In addition to having PAO, 52.6% of hips had an anterior arthrotomy and 19.8% had a hip arthroscopy either to perform an osteochondroplasty of the femoral head-neck junction or to address labral pathologic changes. Of these 553 hips in which the labrum was visualized, labral morphologic status was graded as hypertrophic in 50%, normal in 45%, hypoplastic in 4%, and ossified in less than 1%. Decreased lateral center-edge angle and anterior center-edge angle and increased acetabular inclination were associated with labral hypertrophy, but chronicity of symptoms was not. Of the 553 hips, 64% had tears of the labrum, with the majority being degenerative-type tears. Labral pathologic changes are common in patients with symptomatic acetabular dysplasia. Labral hypertrophy, however, is not a universal finding, particularly in hips with mild dysplasia, and therefore should not be considered a reliable diagnostic criterion for instability.

  12. Abduction bracing for residual acetabular dysplasia in infantile DDH.

    PubMed

    Gans, Itai; Flynn, John M; Sankar, Wudbhav N

    2013-01-01

    Abduction bracing is often used to treat residual acetabular dysplasia in infants whose acetabular indices (AI) exceed 30 degrees after 6 months of age. However, little data exist to support this practice. The purpose of this study was to determine the efficacy of part-time abduction bracing in treating residual acetabular dysplasia by comparing a cohort of braced infants with a cohort of unbraced infants. We performed a retrospective review of a consecutive series of patients with developmental dysplasia of the hip (DDH) treated at our institution over 4 years. Children with stable, treated DDH but residual acetabular dysplasia at 6 months of age were identified; those with available anteroposterior pelvic radiographs at 6 months and 1 year of age were included. Patients who required open surgical reduction and those with syndromic or neuromuscular diagnoses were excluded. On the basis of practice variations at our institution, some orthopaedists start bracing when the 6-month radiograph demonstrates an AI≥30 degrees, whereas others do not; we compared these 2 cohorts. Braced patients were instructed to wear an abduction orthosis during nights and naps until follow-up at 1 year of age. The AI at 6 months and 1 year of age for both cohorts were then measured by a single observer and the differences compared. Seventy-six hips in 52 patients were identified with residual dysplasia on the 6-month radiograph. Thirty-nine hips (27 patients) were unbraced, 31 hips (21 patients) were braced, and 6 hips (4 patients) were excluded for cross-over. Over a 6-month period, the braced cohort had significantly better improvement in the AI of 5.3 degrees (95% confidence interval, 4.3 to 6.3 degrees) compared to the unbraced cohort which had an improvement in the AI of only 1.1 degrees (95% confidence interval 0.6 to 1.6 degrees) (P<0.001). In this comparative analysis of infants with residual acetabular dysplasia treated with abduction bracing or observation, part-time bracing

  13. Acetabular rim and surface segmentation for hip surgery planning and dysplasia evaluation

    NASA Astrophysics Data System (ADS)

    Tan, Sovira; Yao, Jianhua; Yao, Lawrence; Summers, Ronald M.; Ward, Michael M.

    2008-03-01

    Knowledge of the acetabular rim and surface can be invaluable for hip surgery planning and dysplasia evaluation. The acetabular rim can also be used as a landmark for registration purposes. At the present time acetabular features are mostly extracted manually at great cost of time and human labor. Using a recent level set algorithm that can evolve on the surface of a 3D object represented by a triangular mesh we automatically extracted rims and surfaces of acetabulae. The level set is guided by curvature features on the mesh. It can segment portions of a surface that are bounded by a line of extremal curvature (ridgeline or crestline). The rim of the acetabulum is such an extremal curvature line. Our material consists of eight hemi-pelvis surfaces. The algorithm is initiated by putting a small circle (level set seed) at the center of the acetabular surface. Because this surface distinctively has the form of a cup we were able to use the Shape Index feature to automatically extract an approximate center. The circle then expands and deforms so as to take the shape of the acetabular rim. The results were visually inspected. Only minor errors were detected. The algorithm also proved to be robust. Seed placement was satisfactory for the eight hemi-pelvis surfaces without changing any parameters. For the level set evolution we were able to use a single set of parameters for seven out of eight surfaces.

  14. Acetabular revision using a press-fit dual mobility cup.

    PubMed

    Massin, P; Besnier, L

    2010-02-01

    Dual mobility cups are especially indicated in total hip replacement revision, the risk of recurrent instability being greater than in primary surgery. In revision, however, primary cup fixation is uncertain without routine anchoring screws. The stability of dual mobility cups impacted without cement, supplementary screw(s) or anchoring pegs fixation is satisfactory in total hip arthroplasty acetabular component revision, and prevents instability accidents. Twenty three patients were operated on by the same surgeon between January 1999 and December 2006 and prospectively followed up to a mean 4 1/2 years (range,2-10 yrs). A Collégia cup (Wright Medical France, Créteil, France) was impacted in 23 total hip arthroplasty acetabular component revisions, including 17 cases of SOFCOT grade-1 bone-stock loss and six of grade 2. There were six clinically poor results on the Merle D'Aubigné scale. One case of early migration occurred, in a multioperated acetabulum. There was one isolated dislocation and one recurrent dislocation associated with loose greater trochanter nonunion, but tolerated as it was infrequent. This option simplifies revision surgery and limits the risk of dislocation if the abductor muscles unit is continuous. It is indicated when local bone-site compromise encompass a wall-contained cavitary defect at most. A medial wall defect, if moderate, does not in our view preclude using a primary cup, impacted with a certain degree of protrusion. Longer-term follow-up will be needed to confirm these medium-term findings. Level IV. Prospective non comparative therapeutic study. Elsevier Masson SAS. All rights reserved.

  15. Failure of dual radius hydroxyapatite-coated acetabular cups

    PubMed Central

    D'Angelo, Fabio; Molina, Mauro; Riva, Giacomo; Zatti, Giovanni; Cherubino, Paolo

    2008-01-01

    Introduction Many kind of hydroxyapatite-coated cups were used, with favorable results in short term studies; it was supposed that its use could improve osteointegration of the cup, enhancing thus stability and survivorship. The purpose of this study is to analyze the long term behavior of the hemispheric HA coated, Dual Radius Osteonics cup and to discuss the way of failure through the exam of the revised components and of both periacetabular and osteolysis tissue. Materials and Methods Between 1994 and 1997, at the Department of Orthopedic Sciences of the Insubria University, using the posterolateral approach, were implanted 276 Dual Radius Osteonics® in 256 patients, with mean age of 63 years. Results At a mean follow-up of 10 years (range 8–12 years), 183 cups in 165 patients, were available for clinical and radiographical evaluation. 22 Cups among the 183 were revised (11%). The cause of revision was aseptic loosening in 17 cases, septic loosening in one case, periprosthetic fracture in another case, osteolysis and polyethylene wear in two cases and, finally, recurrent dislocations in the last one. In the remaining patients, mean HHS increased from a preoperative value of 50,15 to a postoperative value of 92,69. The mean polyethylene wear was 1,25 mm (min. 0,08, max. 3,9 mm), with a mean annual wear of 0,17 mm. The mean acetabular migration on the two axis was 1,6 mm and 1,8 mm. Peri-acetabular osteolysis were recorded in 89% of the implants (163 cases). The cumulative survivorship (revision as endpoint) at the time was 88,9%. Conclusion Our study confirms the bad behavior of this type of cup probably related to the design, to the method of HA fixation. The observations carried out on the revised cup confirm these hypotheses but did not clarify if the third body wear could be a further problem. Another interesting aspect is the high incidence of osteolysis, which are often asymptomatic becoming a problem for the surgeon as the patient refuses the

  16. Failure of dual radius hydroxyapatite-coated acetabular cups.

    PubMed

    D'Angelo, Fabio; Molina, Mauro; Riva, Giacomo; Zatti, Giovanni; Cherubino, Paolo

    2008-08-07

    Many kind of hydroxyapatite-coated cups were used, with favorable results in short term studies; it was supposed that its use could improve osteointegration of the cup, enhancing thus stability and survivorship. The purpose of this study is to analyze the long term behavior of the hemispheric HA coated, Dual Radius Osteonics cup and to discuss the way of failure through the exam of the revised components and of both periacetabular and osteolysis tissue. Between 1994 and 1997, at the Department of Orthopedic Sciences of the Insubria University, using the posterolateral approach, were implanted 276 Dual Radius Osteonics in 256 patients, with mean age of 63 years. At a mean follow-up of 10 years (range 8-12 years), 183 cups in 165 patients, were available for clinical and radiographical evaluation. 22 Cups among the 183 were revised (11%). The cause of revision was aseptic loosening in 17 cases, septic loosening in one case, periprosthetic fracture in another case, osteolysis and polyethylene wear in two cases and, finally, recurrent dislocations in the last one. In the remaining patients, mean HHS increased from a preoperative value of 50.15 to a postoperative value of 92.69. The mean polyethylene wear was 1.25 mm (min. 0.08, max 3.9 mm), with a mean annual wear of 0.17 mm. The mean acetabular migration on the two axis was 1.6 mm and 1.8 mm. Peri-acetabular osteolysis were recorded in 89% of the implants (163 cases). The cumulative survivorship (revision as endpoint) at the time was 88,9%. Our study confirms the bad behavior of this type of cup probably related to the design, to the method of HA fixation. The observations carried out on the revised cup confirm these hypotheses but did not clarify if the third body wear could be a further problem. Another interesting aspect is the high incidence of osteolysis, which are often asymptomatic becoming a problem for the surgeon as the patient refuses the possibility of a revision.

  17. Improving acetabular cup orientation in total hip arthroplasty by using smartphone technology.

    PubMed

    Peters, Frank M; Greeff, Richard; Goldstein, Neal; Frey, Chris T

    2012-08-01

    Acetabular cup placement in total hip arthroplasty is often difficult to assess, especially in the lateral position and using the posterior approach. Conventional techniques and computer-assisted surgery are the 2 most popular methods for proper placement of the acetabular cup in Lewinnek's safe zone of orientation (anteversion 15° ± 10° and lateral inclination 40° ± 10°). We developed a system that uses the accelerometer and camera function of the iPhone. A level indicator application and protractor application were downloaded to the iPhone and used to improve acetabular cup placement. This system has proven to be accurate and quick. Our series of 50 prospective cases showed good results with all our acetabular cups being placed within a narrow range in the safe zone and with less than 5% difference between the preoperative, intraoperative, and postoperative acetabular inclinations.

  18. Trabecular metal acetabular revision system (cup-cage construct) to address the massive acetabular defects in revision arthroplasty

    PubMed Central

    Malhotra, Rajesh; Kancherla, Ramprasad; Kumar, Vijay; Soral, Aditya

    2012-01-01

    The increasing number of total hip replacements in the younger clique has added to the demand for revision procedures. Revision situations are often encountered with infection, loss of bone stock and bone defects. There are various methods of reconstruction of acetabular defects. The management options of type 3B Paprosky acetabular defects are limited with allograft and conventional cages. Trabecular metal technology has evolved to address these bone defects. Trabecular metal acetabular revision system (TMARS) cup-cage construct is a new technique to address massive acetabular defects. We describe a case of failed hip reconstruction done for a Giant cell tumour of proximal femur managed by a two stage procedure, initial debridement and second stage reconstruction of acetabulum with TMARS cup-cage construct and femur with allograft prosthesis composite. PMID:22912527

  19. Copy number loss in the region of the ASPN gene in patients with acetabular dysplasia: ASPN CNV in acetabular dysplasia.

    PubMed

    Sekimoto, T; Ishii, M; Emi, M; Kurogi, S; Funamoto, T; Yonezawa, Y; Tajima, T; Sakamoto, T; Hamada, H; Chosa, E

    2017-07-01

    We have previously investigated an association between the genome copy number variation (CNV) and acetabular dysplasia (AD). Hip osteoarthritis is associated with a genetic polymorphism in the aspartic acid repeat in the N-terminal region of the asporin (ASPN) gene; therefore, the present study aimed to investigate whether the CNV of ASPN is involved in the pathogenesis of AD. Acetabular coverage of all subjects was evaluated using radiological findings (Sharp angle, centre-edge (CE) angle, acetabular roof obliquity (ARO) angle, and minimum joint space width). Genomic DNA was extracted from peripheral blood leukocytes. Agilent's region-targeted high-density oligonucleotide tiling microarray was used to analyse 64 female AD patients and 32 female control subjects. All statistical analyses were performed using EZR software (Fisher's exact probability test, Pearson's correlation test, and Student's t-test). CNV analysis of the ASPN gene revealed a copy number loss in significantly more AD patients (9/64) than control subjects (0/32; p = 0.0212). This loss occurred within a 60 kb region on 9q22.31, which harbours the gene for ASPN. The mean radiological parameters of these AD patients were significantly worse than those of the other subjects (Sharp angle, p = 0.0056; CE angle, p = 0.0076; ARO angle, p = 0.0065), and all nine patients required operative therapy such as total hip arthroplasty or pelvic osteotomy. Moreover, six of these nine patients had a history of operative or conservative therapy for developmental dysplasia of the hip. Copy number loss within the region harbouring the ASPN gene on 9q22.31 is associated with severe AD. A copy number loss in the ASPN gene region may play a role in the aetiology of severe AD.Cite this article: T. Sekimoto, M. Ishii, M. Emi, S. Kurogi, T. Funamoto, Y. Yonezawa, T. Tajima, T. Sakamoto, H. Hamada, E. Chosa. Copy number loss in the region of the ASPN gene in patients with acetabular dysplasia: ASPN CNV in acetabular

  20. A Contemporary Definition of Hip Dysplasia and Structural Instability: Toward a Comprehensive Classification for Acetabular Dysplasia.

    PubMed

    Wilkin, Geoffrey P; Ibrahim, Mazen M; Smit, Kevin M; Beaulé, Paul E

    2017-09-01

    Hip dysplasia has long been known to be a risk factor for pain and degenerative changes in the hip joint. The diagnosis of dysplasia has historically been based on assessments of acetabular anatomy on the anteroposterior pelvic radiograph, most commonly the lateral center-edge angle. Recent advances in imaging of the dysplastic hip with computerized tomography scans have demonstrated that hip dysplasia is in fact a 3-dimensional (D) deformity of the acetabulum and that multiple patterns of hip instability exist that may not be completely assessed on 2D imaging. A more thorough understanding of acetabular anatomy permits an evolution away from vague terms such as "borderline dysplasia." A 3D assessment of the acetabulum and the resultant patterns of instability may be more appropriate since this would allow more accurate treatment to correct the structural instability with acetabular reorientation. With this information, we propose a diagnostic framework that groups symptomatic dysplastic hips into one of 3 categories based on the primary direction of instability: (1) anterior, (2) posterior, and (3) global. This framework may aid the clinician in developing a differential diagnosis for the assessment of hip pain and suspected instability, and for planning an appropriate surgical management. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. A simplified method to determine acetabular cup anteversion from plain radiographs.

    PubMed

    Widmer, Karl-Heinz

    2004-04-01

    Plain radiographs are the most important diagnostic means for determining the indication and following up on total hip arthroplasty. The acetabular cup position can be easily determined by applying trigonometric functions. This report presents an even simpler method. The short axis of the projected ellipse is measured and related to the total cross-section of the projected cup along the short axis. This relationship correlates with acetabular cup anteversion angles and represents an inverse sinus function. A close linear correlation is seen within the most common interval from 10 degrees to 30 degrees. Anteversion is between 23 degrees to 24 degrees when the ellipse bisects the total acetabular cross-section. This means that simply measuring the length of the short ellipse axis and the total length of the projected cross-section along the short axis provides the radiographic acetabular anteversion. Nonorthogonal projected radiographs should be corrected first.

  2. Successful cementless cup reimplantation using cortical bone graft augmentation after an acetabular fracture and cup displacement.

    PubMed

    Torres, Bryan T; Chambers, Jonathan N; Budsberg, Steven C

    2009-01-01

    To report repair of a periprosthetic acetabular fracture with concurrent component displacement after cementless total hip arthroplasty (THA). Clinical case report. Dog (n=1) with an acetabular fracture after THA. Acetabular repair was performed on a highly comminuted periprosthetic acetabular fracture after cementless THA. A bulk, structural corticocancellous autograft from the ipsilateral ilial wing was used for repair and reconstruction of the dorsal acetabular wall before reimplantation of a cementless acetabular component. Repair of a periprosthetic acetabular fracture with a bulk structural autograft was successful in reconstruction of the dorsal acetabular wall and in reestablishing a stable, functional cementless THA acetabular prosthesis. Structural corticocancellous autografts from the ilium can be successfully used in repair of periprosthetic acetabular fractures after THA. Structural corticocancellous grafting from the ilium can be considered as a treatment option for repair of periprosthetic acetabular fractures after THA.

  3. Cavitary acetabular defects treated with morselized cancellous bone graft and cementless cups

    PubMed Central

    Pereira, G. C.T.; Kubiak, E. N.; Levine, B.; Chen, F. S.

    2006-01-01

    The use of impacted morselized cancellous bone grafts in conjunction with cementless hemispherical acetabular cups for treatment of AAOS type II acetabular cavitary deficiencies was evaluated in a retrospective study of 23 primary and 24 revision total hip arthroplasties, at a mean follow-up of 7.9 and 8.1 years, respectively. All primary hips received autografts, while all revision hips received allografts. Modified Harris Hip Scores for primary and revision hip replacements increased from a pre-operative mean of 37 and 47 to a postoperative mean of 90 and 86, respectively. All 23 autografts and 23 out of 24 cancellous allografts were radiographically incorporated without evidence of resorption. There were no instances of infection, component migration, or cases requiring subsequent acetabular revision. We conclude that impacted morselized cancellous bone-graft augmentation of cementless cups is a viable surgical option for AAOS type II cavitary acetabular defects. PMID:16988799

  4. Does radiographic coxa profunda indicate increased acetabular coverage or depth in hip dysplasia?

    PubMed

    Fujii, Masanori; Nakamura, Tetsuro; Hara, Toshihiko; Nakashima, Yasuharu; Iwamoto, Yukihide

    2015-06-01

    Although radiographic coxa profunda has been considered an indicator of acetabular overcoverage, recent studies suggest that radiographic coxa profunda is a nonspecific finding seen even in hip dysplasia. The morphologic features of coxa profunda in hip dysplasia and the frequency with which the two overlap are not well defined. We determined (1) the prevalence of radiographic coxa profunda in patients with hip dysplasia; (2) the morphologic differences of the acetabulum and pelvis between patients with hip dysplasia and control subjects; and (3) the morphologic differences between hip dysplasia with and without coxa profunda. We retrospectively reviewed the pelvic radiographs and CT scans of 70 patients (70 hips) with hip dysplasia. Forty normal hips were used as controls. Normal hips were defined as those with a lateral center-edge angle between 25° and 40°. Coxa profunda was defined as present when the acetabular fossa was observed to touch or was medial to the ilioischial line on an AP pelvic radiograph. CT measurements included acetabular version, acetabular coverage, acetabular depth, and rotational alignment of the innominate bone. The prevalence of coxa profunda was 44% (31 of 70 hips) in dysplastic hips and 73% (29 of 40 hips) in the control hips (odds ratio, 3.32; 95% CI, 1.43-7.68). Dysplastic hips had a more anteverted and globally shallow acetabulum with inwardly rotated innominate bone compared with the control hips (p < 0.001). Dysplastic hips with coxa profunda had a more anteverted acetabulum (p < 0.001) and inwardly rotated innominate bone (p < 0.002) compared with those without coxa profunda, whereas the acetabular coverage and depth did not differ between the two groups, with the numbers available. Radiographic coxa profunda was not a sign of increased acetabular coverage and depth in patients with hip dysplasia, but rather indicates classic acetabular dysplasia, defined by an anteverted acetabulum with anterolateral acetabular

  5. Acetabular cup position and risk of dislocation in primary total hip arthroplasty

    PubMed Central

    Seagrave, Kurt G; Troelsen, Anders; Malchau, Henrik; Husted, Henrik; Gromov, Kirill

    2017-01-01

    Background and purpose — Hip dislocation is one of the most common complications following total hip arthroplasty (THA). Several factors that affect dislocation have been identified, including acetabular cup positioning. Optimal values for cup inclination and anteversion are debatable. We performed a systematic review to describe the different methods for measuring cup placement, target zones for cup positioning, and the association between cup positioning and dislocation following primary THA. Methods — A systematic search of literature in the PubMed database was performed (January and February 2016) to identify articles that compared acetabular cup positioning and the risk of dislocation. Surgical approach and methods for measurement of cup angles were also considered. Results— 28 articles were determined to be relevant to our research question. Some articles demonstrated that cup positioning influenced postoperative dislocation whereas others did not. The majority of articles could not identify a statistically significant difference between dislocating and non-dislocating THA with regard to mean angles of cup anteversion and inclination. Most of the articles that assessed cup placement within the Lewinnek safe zone did not show a statistically significant reduction in dislocation rate. Alternative target ranges have been proposed by several authors. Interpretation— The Lewinnek safe zone could not be justified. It is difficult to draw broad conclusions regarding a definitive target zone for cup positioning in THA, due to variability between studies and the likely multifactorial nature of THA dislocation. Future studies comparing cup positioning and dislocation rate should investigate surgical approach separately. Standardized tools for measurement of cup positioning should be implemented to allow comparison between studies. PMID:27879150

  6. The medium term outcome of the Omnifit constrained acetabular cup.

    PubMed

    Bigsby, Ewan; Whitehouse, Michael R; Bannister, Gordon C; Blom, Ashley W

    2012-01-01

    Recurrent dislocation requiring revision surgery occurs in approximately 4% of primary total hip arthroplasties (THAs). To reduce this risk, or to treat those patients who recurrently dislocate, a constrained acetabular component may be used, however there are concerns over the success of such components due to increased mechanical stresses. The purpose of this study was to analyse the survivorship and radiological results for the Omnifit constrained acetabular component, providing a longer patient reported outcome follow-up than previous studies. 117 patients (median age 82 years) underwent a THA with an Omnifit constrained acetabular component. Of these, 45 were primary replacements and 72 were revisions. Survivorship analysis was performed and patients were assessed both radiologically and functionally. At follow-up, 53 patients (45.3%) had died at a median time of 33 months from operation. The median overall follow-up was 7.0 (5.5-8.2) years. Survivors (median age 83 years) reported a median Oxford Hip Score (OHS) of 16.6 (0-48), 87.8% were satisfied with their surgery. 45 (91.8%) of the acetabular components were stable radiologically, 48 (96%) of the femoral components were stable (5 uncemented, 43 cemented) and two possibly unstable. Four of the 117 patients underwent further surgery. Only one required revision of the prosthesis and this was for a periprosthetic fracture. In the medium term the Omnifit constrained acetabular component prevents dislocation and does not cause excessive loosening of either the acetabular or femoral components in our patient population. Our results support the use of the Omnifit constrained acetabular component in elderly patients at risk of dislocation with low functional demand.

  7. Cam Deformity and Acetabular Dysplasia as Risk Factors for Hip Osteoarthritis.

    PubMed

    Saberi Hosnijeh, Fatemeh; Zuiderwijk, Maria E; Versteeg, Mathijs; Smeele, Hieronymus T W; Hofman, Albert; Uitterlinden, André G; Agricola, Rintje; Oei, Edwin H G; Waarsing, Jan H; Bierma-Zeinstra, Sita M; van Meurs, Joyce B J

    2017-01-01

    Cam deformity and acetabular dysplasia have been recognized as relevant risk factors for hip osteoarthritis (OA) in a few prospective studies with limited sample sizes. To date, however, no evidence is available from prospective studies regarding whether the magnitude of these associations differs according to sex, body mass index (BMI), and age. Participants in the Rotterdam Study cohort including men and women ages 55 years or older without OA at baseline (n = 4,438) and a mean follow-up of 9.2 years were included in the study. Incident radiographic OA was defined as a Kellgren/Lawrence grade of ≥2 or a total hip replacement at follow-up. Alpha and center-edge angles were measured to determine the presence of cam deformity and acetabular dysplasia/pincer deformity, respectively. Odds ratios (ORs) were calculated to assess the associations between both deformities and the development of OA. Subjects with cam deformity (OR 2.11, 95% confidence interval [95% CI] 1.55-2.87) and those with acetabular dysplasia (OR 2.19, 95% CI 1.50-3.21) had a 2-fold increased risk of developing OA compared with subjects without deformity, while pincer deformity did not increase the risk of OA. Stratification analyses showed that the associations of cam deformity and acetabular dysplasia with OA were driven by younger individuals, whereas BMI did not influence the associations. Female sex appears to modify the risk of hip OA related to acetabular dysplasia. Individuals with cam deformity and those with acetabular dysplasia are predisposed to OA; these associations were independent of other well-known risk factors. Interestingly, both deformities predisposed to OA only in relatively young individuals. Therefore, early identification of these conditions is important. © 2016, American College of Rheumatology.

  8. Wear of gamma-crosslinked polyethylene acetabular cups against roughened femoral balls.

    PubMed

    McKellop, H; Shen, F W; DiMaio, W; Lancaster, J G

    1999-12-01

    Crosslinking of ultrahigh molecular weight polyethylene has been shown to markedly improve its wear resistance in clinical studies and laboratory tests using hip joint simulators. However, because most of the laboratory studies have been done under clean conditions using prosthesis-quality, highly polished counterfaces, there is concern regarding how well an intentionally crosslinked polyethylene acetabular cup will resist abrasion by a femoral ball that has been damaged by third-body abrasion in vivo. To investigate this, conventional and radiation crosslinked-remelted acetabular cups of ultra-high molecular weight polyethylene were tested in a hip joint simulator bearing against smooth femoral balls and against balls with moderate and severe roughening. Cups were tested with and without aging to accelerate any oxidative degradation. The crosslinked cups were produced by exposing extruded GUR 4150 bar stock of ultrahigh molecular weight polyethylene to 5 Mrad gamma radiation under a partial vacuum and then the bars were remelted to extinguish residual free radicals. Artificial aging at 70 degrees C under 5 atm oxygen for 14 days induced negligible oxidation in the crosslinked and remelted material. Against smooth balls, the wear of the crosslinked cups, with or without aging, averaged approximately 15% of that of the conventional cups. Against the moderately rough balls, the wear rate of the conventional cups was unchanged, whereas the wear rate increased slightly for the nonaged and aged crosslinked cups, but was still only 26% and 20% of that of the conventional cups, respectively. Against extremely rough balls, the mean wear rates increased markedly for each material such that during the final 1 million cycle interval, the average wear rates of the nonaged and the aged crosslinked cups were 72% and 47% of that of the conventional cups, respectively. That is, the crosslinked polyethylene showed substantially better wear resistance than conventional polyethylene

  9. Acetabular revisions using a cementless oblong cup: five to ten year results

    PubMed Central

    Capone, A.; Carulli, C.; Villano, M.; Gusso, M. I.

    2007-01-01

    The purpose of this paper was to evaluate the results of acetabular revisions with the use of an oblong revision cup that is designed with its longitudinal diameter elongated relative to its transverse diameter. Between 1996 and 2001, 62 hips in 60 patients underwent an acetabular revision with the insertion of a LOR acetabular component. Seven hips were lost to follow-up or the patients died; the remaining 55 hips (53 patients) remained in follow-up for an average of 7.2 years (range: 5.0–10.1 years). One socket was revised for aseptic loosening, and another was operated on for a late polyethylene liner dissociation. The average Harris hip score (HHS) improved from 34 to 79. Results were rated as excellent in 16 hips, good in 28, fair in six and poor in three. Radiographic analysis demonstrated an improvement in the average vertical displacement of the hip centre: 49 hips had a well-fixed, bone-ingrown cup and four had a stable fibrous union. For large superolateral acetabular bone deficiencies, this implant facilitated a complex reconstruction without the need for bulk structural acetabular bone grafts, provided good clinical results and showed satisfactory stability at the midterm follow-up. PMID:17221262

  10. Vibrational spectroscopy study of the oxidation of Hylamer UHMWPE explanted acetabular cups sterilized differently

    NASA Astrophysics Data System (ADS)

    Reggiani, Matteo; Tinti, Anna; Visentin, Manuela; Stea, Susanna; Erani, Paolo; Fagnano, Concezio

    2007-05-01

    Ultra-high-molecular-weight polyethylene (UHMWPE) has been used for over 40 years for acetabular cups in total hip joint prosthesis. Hylamer is a hot isostatically pressed material with high crystallinity. Early loosening due to extensive oxidation and phase transformation has been observed for this material. To analyze the reasons for its high tendency to oxidize, we have examined by FT-IR spectroscopy explanted acetabular cups γ-sterilized in different ways. The oxidation and wear rate observed were: Hylamer cups γ-sterilized in air with a long shelf life > Hylamer cups γ-sterilized in air with short shelf life ⩾ Hylamer cups γ-sterilized in nitrogen. Our data indicate the important role of the shelf life on the oxidation of the cups: the samples γ-sterilized in air characterized by a shelf life greater than 3 years showed severe oxidation, a high wear rate, and marked debris production with delamination and the formation of a brittle zone in the more oxidated regions. In these regions we observed an increase in crystallinity, which was probably due to the decrease in the molecular weight of PE. The high oxidation was probably due to the modifications induced by the material treatment.

  11. Revisions of Extensive Acetabular Defects with Impaction Grafting and a Cement Cup

    PubMed Central

    van Egmond, Nienke; De Kam, Daniel C. J.; Gardeniers, Jean W. M.

    2010-01-01

    Background Loosening of acetabular components often leads to bony defects. Management of extensive acetabular bone loss in hip revision arthroplasty can be a tremendous challenge. Questions/purposes We asked whether a reconstruction with impacted bone grafts will provide a durable and pain-free function in extensive acetabular defects. We specifically determined the (1) survival rates with the end point of revision for any reason, aseptic revision, and radiographic loosening; (2) visual analog scale (VAS) pain score, Harris hip score (HHS), and the Oxford Hip Questionnaire score (OHQS); (3) number of repeat revisions; (4) complications; and (5) radiographic loosening, wear, and radiolucencies. Patients and Methods We retrospectively followed 25 patients (27 hips) with extensive acetabular defects. No patient was lost to followup. Two patients died during followup. Minimum followup was 3 years (mean, 8.8 years; range, 3–14.1 years). Results Three patients (three hips) underwent repeat revision surgery and another two patients (two hips) had radiographically loose hips. The 10-year survival rate was 88% (95% confidence interval, 74.2%–100%) with the end point acetabular revision for any reason and 95% (95% confidence interval, 86.0%–100%) with the end point acetabular revision for aseptic loosening. The mean HHSs were 55 points before surgery and 72 points postoperatively. Conclusions Acetabular reconstruction with impaction bone grafting and a cemented cup is a reliable technique with a 10-year survival rate of 88% in patients with extensive acetabular deficiencies. Level of Evidence Level IV, case series. See the Guidelines for Authors for a complete description of levels of evidence. PMID:20931308

  12. Central X-ray beam correction of radiographic acetabular cup measurement after THA: an experimental study.

    PubMed

    Schwarz, T; Weber, M; Wörner, M; Renkawitz, T; Grifka, J; Craiovan, B

    2017-05-01

    Accurate assessment of cup orientation on postoperative radiographs is essential for evaluating outcome after THA. However, accuracy is impeded by the deviation of the central X-ray beam in relation to the cup and the impossibility of measuring retroversion on standard pelvic radiographs. In an experimental trial, we built an artificial cup holder enabling the setting of different angles of anatomical anteversion and inclination. Twelve different cup orientations were investigated by three examiners. After comparing the two methods for radiographic measurement of the cup position developed by Lewinnek and Widmer, we showed how to differentiate between anteversion and retroversion in each cup position by using a second plane. To show the effect of the central beam offset on the cup, we X-rayed a defined cup position using a multidirectional central beam offset. According to Murray's definition of anteversion and inclination, we created a novel corrective procedure to balance measurement errors caused by deviation of the central beam. Measurement of the 12 different cup positions with the Lewinnek's method yielded a mean deviation of [Formula: see text] (95 % CI 1.3-2.3) from the original cup anteversion. The respective deviation with the Widmer/Liaw's method was [Formula: see text] (95 % CI 2.4-4.0). In each case, retroversion could be differentiated from anteversion with a second radiograph. Because of the multidirectional central beam offset ([Formula: see text] cm) from the acetabular cup in the cup holder ([Formula: see text] anteversion and [Formula: see text] inclination), the mean absolute difference for anteversion was [Formula: see text] (range [Formula: see text] to [Formula: see text] and [Formula: see text] (range [Formula: see text] to [Formula: see text] for inclination. The application of our novel mathematical correction of the central beam offset reduced deviation to a mean difference of [Formula: see text] for anteversion and [Formula: see text

  13. The influence of acetabular cup material on pelvis cortex surface strains, measured using digital image correlation.

    PubMed

    Dickinson, A S; Taylor, A C; Browne, M

    2012-02-23

    Acetabular cup loosening is a late failure mode of total hip replacements, and peri-prosthetic bone deterioration may promote earlier failure. Preservation of supporting bone quality is a goal for implant design and materials selection, to avoid stress shielding and bone resorption. Advanced polymer composite materials have closer stiffness to bone than metals, ceramics or polymers, and have been hypothesised to promote less adverse bone adaptation. Computer simulations have supported this hypothesis, and the present study aimed to verify this experimentally. A composite hemi-pelvis was implanted with Cobalt Chromium (CoCr), polyethylene (UHMWPE) and MOTIS(®)carbon-fibre-reinforced polyether etherketone (CFR-PEEK) acetabular cups. In each case, load was applied to the implanted pelvis and Digital Image Correlation (DIC) was used for surface strain measurement. The test was repeated for an intact hemi-pelvis. Trends in implanted vs. intact bone principal strains were inspected to assess the average principal strain magnitude change, allowing comparison of the potential bone responses to implantation with the three cups. The CFR-PEEK cup was observed to produce the closest bone strain to the intact hip in the main load path, the superior peri-acetabular cortex (+12% on average, R(2)=0.84), in comparison to CoCr (+40%, R(2)=0.91) and UHWMPE cups (-26%, R(2)=0.94). Clinical observations have indicated that increased periacetabular cortex loading may result in reduced polar cancellous bone loading, leading to longer term losses in periprosthetic bone mineral density. This study provides experimental evidence to verify previous computational studies, indicating that cups produced using materials with stiffness closer to cortical bone recreate physiological cortical bone strains more closely and could, therefore, potentially promote less adverse bone adaptation than stiffer press-fitted implants in current use.

  14. Early failure of a polyethylene acetabular liner cemented into a metal cup.

    PubMed

    Wilson, David A J; Corkum, Joseph P; Teeter, Matthew G; Holdsworth, David W; Dunbar, Michael J

    2012-05-01

    In 2002, a patient underwent revision total hip arthroplasty for polyethylene wear. The acetabular cup was well fixed, and it was decided to cement a new polyethylene liner into the existing cup. In 2006, the patient presented with inability to weight bear and easy subluxation of the hip. Revision surgery was performed, and all components were examined postoperatively. Investigation with microcomputed tomography revealed that the liner had plastically deformed at the superior pole resulting in the hip instability. The reasons for this are suspected to be related to the abducted nature of the original cup and an uneven cement mantle. This report suggests that cementation of polyethylene liners into metal cups has limitations and is not appropriate in all circumstances. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. A Monoblock Porous Tantalum Acetabular Cup Has No Osteolysis on CT at 10 Years

    PubMed Central

    Ghate, Raju; Salaz, Noel; Ghodasra, Jason; Stulberg, S. David

    2010-01-01

    Background Aseptic osteolysis has been the single most important factor limiting the longevity of a THA. A great deal of attention has been focused on the development of implants and materials that minimize the development of osteolysis. The monoblock porous tantalum acetabular cup was designed to minimize osteolysis, but whether it does so is unclear. Questions/purposes We evaluated the incidence of osteolytic lesions after THA using a monoblock porous tantalum acetabular component. Methods We retrospectively reviewed 51 patients who had a THA using a monoblock porous tantalum acetabular cup. At a minimum of 9.6 years postoperatively (average, 10.3 years; SD, 0.2 years; range, 9.6–10.8 years), a helical CT scan of the pelvis using a metal suppression protocol was obtained. This scan was evaluated for the presence of osteolysis. Results We found no evidence of osteolysis on CT scan at an average of 10.3 years. Conclusions Osteolysis appears not to be a major problem at 10 years with this monoblock porous tantalum acetabular component, but longer term followup will be required to determine whether these findings persist. Level of Evidence Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence. PMID:20809172

  16. A new method for the measurement of anteversion of the acetabular cup after total hip arthroplasty.

    PubMed

    Aydogan, Mehmet; Burç, Halil; Saka, Gursel

    2014-08-01

    Many methods of determining the anteversion of the acetabular cup have been described in the literature. The advantages and disadvantages of each of these methods are discussed in this paper. We present a new method of measuring the acetabular anteversion at the anteroposterior hip. The formula designed by the authors was anteversion angle (α) = arc sin |PK|/√ |AK| × |BK|. The formula was tested using the AutoCAD software, and an experimental study was conducted to evaluate the accuracy. Three groups were created, and 16 X-ray images were taken and coded. Ten orthopaedic surgeons measured the acetabular anteversion from these X-rays using our formula. The results in Group 1 were closer to the actual value; in contrast, the results in Group 2 differed from the actual values. The results in Group 3 were as close to the actual anteversion values as were those in Group 1. Developments in technology often bring an increase in complications. Despite newly developed surgical methods and technology, the position of the acetabular cup is still used to determine the results of a total hip arthroplasty. Our method is simple, cost-effective and achieves almost 100 % accuracy.

  17. Acetabuloplasties at Open Reduction Prevent Acetabular Dysplasia in Intentionally Delayed Developmental Dysplasia of the Hip: A Case-control Study.

    PubMed

    Carsi, M Belen; Clarke, Nicholas M P

    2016-05-01

    Avascular necrosis (AVN) and residual acetabular dysplasia are the two main complications of developmental dysplasia of the hip (DDH) treatment. Although early reduction of the hip may decrease the incidence of residual dysplasia, it may increase the incidence of AVN and vice versa. However, we do not know if changes in surgical technique may lead to a modification in these outcomes. Does an incomplete periacetabular acetabuloplasty, as an added step to delayed open reduction, (1) diminish the risk of developing acetabular dysplasia; or (2) increase the rate of AVN compared with patients treated with open reduction alone? We conducted a retrospective matched case-control study comparing 22 patients (27 hips) with early isolated DDH who underwent intentionally delayed open reduction and acetabuloplasty from 2004 to 2010 and followed up > 4 years (88% of the cohort) with early historic controls treated with delayed open reduction alone. Of 53 patients available for matching, 45 (85%) had enough followup (> 10 years) to be considered. They were matched one to one for age at presentation and bilaterality (fuzz 45, 0). This generated a control group of 25 patients (27 hips). The mean followup was different between the groups (p < 0.001). Residual dysplasia considered when center-edge angle < 15° (6-13 years old) or < 20° (≥ 14 years old) or as a nonevolving acetabular index > 30° and pelvic osteotomies were used as our primary outcomes. The proportion of patients with AVN was also compared. Patients treated with open reduction and an incomplete periacetabular acetabuloplasty were less likely to develop acetabular dysplasia and undergo pelvic osteotomies than were patients in the control group (0% [zero of 27] versus 37% [10 of 27]; odds ratio [OR], 11; 95% confidence interval [CI], 2-80; p = 0.02 and 0% [zero of 27] versus 26% [seven of 27]; OR, 8; 95% CI, 1-60; p = 0.025, respectively). With the available numbers, there was no difference in terms of the proportion

  18. Long-term Radiographic Assessment of Cemented Polyethylene Acetabular Cups

    PubMed Central

    Isaac, Graham; Porter, Neil; Fisher, John; Older, John

    2008-01-01

    In vitro studies demonstrating excessive wear in polyethylene cups sterilized using gamma irradiation and stored in air led to the abandonment of this sterilization technique. We evaluated the clinical wear performance of a metal femoral component on a polyethylene cup in a hip prosthesis from a selected subset of implants in a group of patients followed for at least 20 years and assessed the time dependency of variation in penetration rates. We measured penetration in 33 polyethylene cups in 25 patients who had a Charnley low-friction arthroplasty between 1982 and 1984. All patients had Charnley Ogee® cups implanted for more than 20 years and sterilized using the gamma irradiation in air technique. If degradation occurred over time in vivo, it was not reflected by an increased penetration rate with increasing time in vivo; even after 20 years of implantation, the degree of wear remained low. This suggests gamma irradiation affects wear on ultra-high-molecular-weight polyethylene by reducing wear secondary to the crosslinking, by increasing wear as shown through in vitro studies of heavily oxidized samples, or by oxidation resulting from prolonged shelf life. The effect of progressive oxidation in vivo does not appear to affect wear in vivo. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18196419

  19. The effect of acetabular cup size on the short-term stability of revision hip arthroplasty: a finite element investigation.

    PubMed

    Phillips, A T M; Pankaj; Usmani, A S; Howie, C R

    2004-01-01

    The study uses idealized two-dimensional finite element models to examine the behaviour of the acetabular construct following revision hip arthroplasty, carried out using the Slooff-Ling impaction grafting technique. The behaviour of bone graft was considered in detail, with non-linear elasticity and non-associated plasticity being adopted. Load was applied to the acetabular construct through a femoral head using smooth sliding surfaces. In particular, four models were subjected to two idealized cyclic load cases to investigate the effect of acetabular cup size on the short-term stability of the acetabular construct. The study suggests that benefits may be gained by using the largest practical size of acetabular cup.

  20. Developmental dysplasia of the hip in neonates: evolution of acetabular dysplasia after hip stabilization by brief Pavlik harness treatment.

    PubMed

    Bin, K; Laville, J-M; Salmeron, F

    2014-06-01

    The recommended treatment duration in neonates with developmental dysplasia of the hip (DDH) varies depending on whether prolonged Pavlik harness therapy is believed to favourably affect the course of the acetabular dysplasia. According to one theory, several months of additional Pavlik harness therapy after achieving hip reduction contributes to correct the acetabular dysplasia. Another theory holds that hip dislocation induces the acetabular dysplasia, which corrects spontaneously once the femoral head is properly seated in the acetabulum. Here, we evaluated this second theory by studying outcomes after early brief Pavlik harness therapy. Acetabular dysplasia associated with neonatal hip instability undergoes self-correction provided stable hip reduction is achieved very early after birth. Therefore, the duration of Pavlik harness therapy can be substantially shortened. We defined hip instability as either reducible hip dislocation or a very easily dislocatable hip with a soft clunk precluding determination of spontaneous hip position as dislocated or reduced. Static and dynamic ultrasound scans were obtained. Patients with ultrasonographic instability (pubo-femoral distance>5mm with less than 50% of coverage) underwent a second physical examination and received treatment. We re-evaluated 42 abnormal hips in 30 patients after a mean follow-up of 6.7 years (range, 5-14 years). Mean age at treatment initiation was 5 days (range, 1-15 days) and mean treatment duration was 34 days (range, 15-75 days). Mean acetabular angle was 20° (range, 12°-30°) and mean Wiberg's lateral centre-edge angle was 30° (range, 22°-35°). Blunting of the lateral angle of the bony roof was noted in 8 hips at last follow-up. In 1 patient whose hip was stable clinically but unstable by ultrasonography at 21 days of age, recurrent dislocation occurred at 5 months of age. The Severin class was 1a in all patients. Despite continuing controversy about whether hip dislocation induces

  1. A new predictive indicator by arthrography for future acetabular growth following conservative treatment of developmental dysplasia of the hip.

    PubMed

    Satsuma, Shinichi; Kobayashi, Daisuke; Kinugasa, Maki; Takeoka, Yoshiki; Kuroda, Ryosuke; Kurosaka, Masahiro

    2016-05-01

    The aim of this study was to find a new predictive indicator for acetabular growth of developmental dysplasia of the hip. Seventy-three hips that were diagnosed with developmental dysplasia of the hip and treated by conservative reduction were included in our study. In 30 hips with center-edge angle ≤ 10° at age 4, the center-edge of the acetabular limbus angle (CEALA) in the arthrogram was measured. On the basis of the results, CEALA was significantly smaller in the secondary acetabular dysplasia group than in the normal group at maturity. In conclusion, CEALA is a more reliable and accurate predictive indicator for acetabular development than center-edge angle or acetabular index.

  2. Improving the accuracy of acetabular cup implantation using a bulls-eye spirit level.

    PubMed

    Macdonald, Duncan; Gupta, Sanjay; Ohly, Nicholas E; Patil, Sanjeev; Meek, R; Mohammed, Aslam

    2011-01-01

    Acetabular introducers have a built-in inclination of 45 degrees to the handle shaft. With patients in the lateral position, surgeons aim to align the introducer shaft vertical to the floor to implant the acetabulum at 45 degrees. We aimed to determine if a bulls-eye spirit level attached to an introducer improved the accuracy of implantation. A small circular bulls-eye spirit level was attached to the handle of an acetabular introducer. A saw bone hemipelvis was fixed to a horizontal, flat surface. A cement substitute was placed in the acetabulum and subjects were asked to implant a polyethylene cup, aiming to obtain an angle of inclination of 45 degrees. Two attempts were made with the spirit level masked and two with it unmasked. The distance of the air bubble from the spirit level's center was recorded by a single assessor. The angle of inclination of the acetabular component was then calculated. Subjects included both orthopedic consultants and trainees. Twenty-five subjects completed the study. Accuracy of acetabular implantation when using the unmasked spirit level improved significantly in all grades of surgeon. With the spirit level masked, 12 out of 50 attempts were accurate at 45 degrees inclination; 11 out of 50 attempts were "open," with greater than 45 degrees of inclination, and 27 were "closed," with less than 45 degrees. With the spirit level visible, all subjects achieved an inclination angle of exactly 45 degrees. A simple device attached to the handle of an acetabular introducer can significantly improve the accuracy of implantation of a cemented cup into a saw bone pelvis in the lateral position.

  3. How Often Does Femoroacetabular Impingement Occur After an Innominate Osteotomy for Acetabular Dysplasia?

    PubMed

    Castañeda, Pablo; Vidal-Ruiz, Carlos; Méndez, Alfonso; Salazar, Diego Pérez; Torres, Armando

    2016-05-01

    Femoroacetabular impingement is increasingly recognized as a cause of hip pain but its incidence after an innominate osteotomy for the correction of acetabular dysplasia has not been determined. This information would be essential for the orthopaedic surgeon because it has the potential to produce a poor outcome in the long term when trying to balance acetabular instability and overcorrection. The purposes of our study were (1) to determine the frequency with which clinically relevant femoroacetabular impingement (FAI) occurs after an innominate osteotomy for the treatment of acetabular dysplasia; (2) to determine risk factors for the development of FAI; and (3) to compare postoperative radiographic and clinical outcomes in patients having undergone an innominate osteotomy for the correction of acetabular dysplasia both with and without FAI. This was a retrospective review of 154 hips (132 patients) that had undergone an innominate osteotomy for acetabular dysplasia and were evaluated at a minimum followup of 10 years (mean = 12 years). Mean age at the time of surgery was 3 years, 114 hips had a concomitant open reduction, and 54 hips also had femoral shortening. One hundred eight hips had a Salter osteotomy and 46 had a Pemberton osteotomy. Radiographs were analyzed to determine the lateral center-edge angle (CE angle) and the presence of a crossover sign. The diagnosis of FAI was established when the CE angle was greater than 40°, there was a positive crossover sign, and the patient had groin pain when flexing the hip less than 90°. Comparisons between nonparametric variables were performed with a Mann-Whitney's U test. Categorical variables were compared with a chi-square test. Change in acetabular index (correction) was dichotomized considering 20° of correction as the cutoff point. Association is presented as odds ratio (95% confidence interval), and logistic regression was performed. According to our criteria, 18 of 154 hips had FAI (12%). Of the 18

  4. Effect of acetabular cup abduction angle on wear of ultrahigh-molecular-weight polyethylene in hip simulator testing.

    PubMed

    Korduba, Laryssa A; Essner, Aaron; Pivec, Robert; Lancin, Perry; Mont, Michael A; Wang, Aiguo; Delanois, Ronald E

    2014-10-01

    The effect of acetabular component positioning on the wear rates of metal-on-polyethylene articulations has not been extensively studied. Placement of acetabular cups at abduction angles of more than 40° has been noted as a possible reason for early failure caused by increased wear. We conducted a study to evaluate the effects of different acetabular cup abduction angles on polyethylene wear rate, wear area, contact pressure, and contact area. Our in vitro study used a hip joint simulator and finite element analysis to assess the effects of cup orientation at 4 angles (0°, 40°, 50°, 70°) on wear and contact properties. Polyethylene bearings with 28-mm cobalt-chrome femoral heads were cycled in an environment mimicking in vivo joint fluid to determine the volumetric wear rate after 10 million cycles. Contact pressure and contact area for each cup abduction angle were assessed using finite element analysis. Results were correlated with cup abduction angles to determine if there were any differences among the 4 groups. The inverse relationship between volumetric wear rate and acetabular cup inclination angle demonstrated less wear with steeper cup angles. The largest abduction angle (70°) had the lowest contact area, largest contact pressure, and smallest head coverage. Conversely, the smallest abduction angle (0°) had the most wear and most head coverage. Polyethylene wear after total hip arthroplasty is a major cause of osteolysis and aseptic loosening, which may lead to premature implant failure. Several studies have found that high wear rates for cups oriented at steep angles contributed to their failure. Our data demonstrated that larger cup abduction angles were associated with lower, not higher, wear. However, this potentially "protective" effect is likely counteracted by other complications of steep cup angles, including impingement, instability, and edge loading. These factors may be more relevant in explaining why implants fail at a higher rate if

  5. In vitro evaluation of the acetabular cup primary stability by impact analysis.

    PubMed

    Michel, Adrien; Bosc, Romain; Vayron, Romain; Haiat, Guillaume

    2015-03-01

    The implant primary stability of the acetabular cup (AC) is an important parameter for the surgical success of press-fit procedures used for the insertion of cementless hip prostheses. In previous studies by our group (Mathieu, V., Michel, A., Lachaniette, C. H. F., Poignard, A., Hernigou, P., Allain, J., and Haiat, G., 2013, "Variation of the Impact Duration During the in vitro Insertion of Acetabular Cup Implants," Med. Eng. Phys., 35(11), pp. 1558-1563) and (Michel, A., Bosc, R., Mathieu, V., Hernigou, P., and Haiat, G., 2014, "Monitoring the Press-Fit Insertion of an Acetabular Cup by Impact Measurements: Influence of Bone Abrasion," Proc. Inst. Mech. Eng., Part H, 228(10), pp. 1027-1034), the impact momentum and duration were shown to carry information on the press-fit insertion of the AC within bone tissue. The aim of the present study is to relate the impact momentum recorded during the AC insertion to the AC biomechanical primary stability. The experimental protocol consisted in testing 13 bovine bone samples that underwent successively series of 15 reproducible mass falls impacts (5 kg, 5 cm) followed by tangential stability testing. Each bone sample was tested with different hole sizes in order to obtain different stability configurations. The impact momentum and the tangential primary stability reach a maximum value for an interference fit equal to around 1 mm. Moreover, a correlation between the impact momentum and the stability was obtained with all samples and all configuration (R2 = 0.65). The implant primary stability can be assessed through the measurement of the impact force signal analysis. This study opens new paths for the development of a medical device which could be used as a decision support system to assist the surgeon during the insertion of the AC implant.

  6. Postural correction reduces hip pain in adult with acetabular dysplasia: a case report

    PubMed Central

    Lewis, Cara L.; Khuu, Anne; Marinko, Lee

    2015-01-01

    Developmental dysplasia of the hip is often diagnosed in infancy, but less severe cases of acetabular dysplasia are being detected in young active adults. The purpose of this case report is to present a non-surgical intervention for a 31-year-old female with mild acetabular dysplasia and an anterior acetabular labral tear. The patient presented with right anterior hip and groin pain, and she stood with the trunk swayed posterior to the pelvis (swayback posture). The hip pain was reproduced with the anterior impingement test. During gait, the patient maintained the swayback posture and reported 6/10 hip pain. Following correction of the patient’s posture, the patient’s pain rating was reduced to a 2/10 while walking. The patient was instructed to maintain the improved posture. At the 1 year follow-up, she demonstrated significantly improved posture in standing and walking. She had returned to recreational running and was generally pain-free. The patient demonstrated improvement on self-reported questionnaires for pain, function and activity. These findings suggest that alteration of posture can have an immediate and lasting effect on hip pain in persons with structural abnormality and labral pathology. PMID:25731688

  7. Effects of screw eccentricity on the initial stability of the acetabular cup in artificial foam bone of different qualities.

    PubMed

    Hsu, Jui-Ting; Lin, Dan-Jae

    2010-01-01

    Acetabular cup loosening is one of the major failure models of total hip replacement (THR), which is mostly due to insufficient initial stability of the cup. Previous studies have demonstrated that cup stability is affected by the quality of the host bone and the surgical skill when inserting screws. The purpose of this study was to determine the effects on the initial stability of the acetabular cup of eccentric screws in bone of different qualities. In this study, hemispherical cups were fixed into bone specimens constructed from artificial foam with three elastic moduli using one to three screws. The effects of two types of screw eccentricity (offset and angular) on the stability of the acetabular cup were also evaluated. The experimental results indicate that in the presence of ideal screwing, the cup was stable in bone specimens constructed from foam with the highest elastic modulus. In addition, increasing the number of ideal screws enhanced the cup stability, especially in bone specimens constructed from soft foam. Moreover, the cup stability was most affected by offset eccentric screw(s) in the hard-foam bone specimens and by angular eccentric screw(s) in the soft-foam bone specimens. The reported results indicate that the presence of screw eccentricity affects the initial stability of the acetabular cup. Surgeons should keep this in mind when performing screw insertions in THR. However, care is necessary when translating these results to the intraoperative situation due to the experiments being conducted under laboratory conditions, and hence, future studies should attempt to replicate the results reported here in vivo.

  8. Relationship Between Developmental Dislocation of the Hip in Infant and Acetabular Dysplasia at Skeletal Maturity

    PubMed Central

    Okano, Kunihiko; Yamaguchi, Kazumasa; Ninomiya, Yoshikazu; Matsubayashi, Shohei; Aoyagi, Kiyoshi; Osaki, Makoto; Enomoto, Hiroshi; Takahashi, Katsuro

    2015-01-01

    Abstract Previous reports demonstrated 8–60% patients treated for developmental dislocation of hip (DDH) in infancy have residual acetabular dysplasia (AD) at skeletal maturity. AD patients reportedly exhibit abnormal morphology of the pelvis, high rates of comorbid spinal congenital anomalies and high bone mineral density. These physical findings suggest that AD patients have genetic background. We examined the percentage of AD patients with hip pain at skeletal maturity having a history of DDH in infancy and the correlation between the severity of AD at skeletal maturity and history of DDH treatment to investigate the relationship between AD and DDH. A total of 245 patients were radiographically examined for any history of DDH treatment in infancy. The study included 226 women and 19 men with a mean age at examination of 40.7 years (range 17–59 years). Eighty-eight patients (36%) had a history of DDH treatment (DDH group) and the remaining 157 patients (64%) had no history of DDH treatment (non-DDH group). The average age was lower and acetabular angle was larger in the DDH group. There was a significant increasing trend of the percentage of DDH patients associated with the severity of AD classified with CE, acetabular angle, and acetabular roof angle. Our data suggest that there are several AD patients without a history of DDH in Japan, and AD in patients without a history of DDH has different characteristics from AD in patients with a history of DDH. PMID:25569642

  9. Relationship between developmental dislocation of the hip in infant and acetabular dysplasia at skeletal maturity.

    PubMed

    Okano, Kunihiko; Yamaguchi, Kazumasa; Ninomiya, Yoshikazu; Matsubayashi, Shohei; Aoyagi, Kiyoshi; Osaki, Makoto; Enomoto, Hiroshi; Takahashi, Katsuro

    2015-01-01

    Previous reports demonstrated 8-60% patients treated for developmental dislocation of hip (DDH) in infancy have residual acetabular dysplasia (AD) at skeletal maturity. AD patients reportedly exhibit abnormal morphology of the pelvis, high rates of comorbid spinal congenital anomalies and high bone mineral density. These physical findings suggest that AD patients have genetic background. We examined the percentage of AD patients with hip pain at skeletal maturity having a history of DDH in infancy and the correlation between the severity of AD at skeletal maturity and history of DDH treatment to investigate the relationship between AD and DDH.A total of 245 patients were radiographically examined for any history of DDH treatment in infancy. The study included 226 women and 19 men with a mean age at examination of 40.7 years (range 17-59 years).Eighty-eight patients (36%) had a history of DDH treatment (DDH group) and the remaining 157 patients (64%) had no history of DDH treatment (non-DDH group). The average age was lower and acetabular angle was larger in the DDH group. There was a significant increasing trend of the percentage of DDH patients associated with the severity of AD classified with CE, acetabular angle, and acetabular roof angle.Our data suggest that there are several AD patients without a history of DDH in Japan, and AD in patients without a history of DDH has different characteristics from AD in patients with a history of DDH.

  10. The effect of geometry and abduction angle on the stresses in cemented UHMWPE acetabular cups – finite element simulations and experimental tests

    PubMed Central

    Korhonen, Rami K; Koistinen, Arto; Konttinen, Yrjö T; Santavirta, Seppo S; Lappalainen, Reijo

    2005-01-01

    Background Contact pressure of UHMWPE acetabular cup has been shown to correlate with wear in total hip replacement (THR). The aim of the present study was to test the hypotheses that the cup geometry, abduction angle, thickness and clearance can modify the stresses in cemented polyethylene cups. Methods Acetabular cups with different geometries (Link®: IP and Lubinus eccentric) were tested cyclically in a simulator at 45° and 60° abduction angles. Finite element (FE) meshes were generated and two additional designs were reconstructed to test the effects of the cup clearance and thickness. Contact pressures at cup-head and cup-cement interfaces were calculated as a function of loading force at 45°, 60° and 80° abduction angles. Results At the cup-head interface, IP experienced lower contact pressures than the Lubinus eccentric at low loading forces. However, at higher loading forces, much higher contact pressures were produced on the surface of IP cup. An increase in the abduction angle increased contact pressure in the IP model, but this did not occur to any major extent with the Lubinus eccentric model. At the cup-cement interface, IP experienced lower contact pressures. Increased clearance between cup and head increased contact pressure both at cup-head and cup-cement interfaces, whereas a decreased thickness of polyethylene layer increased contact pressure only at the cup-cement interface. FE results were consistent with experimental tests and acetabular cup deformations. Conclusion FE analyses showed that geometrical design, thickness and abduction angle of the acetabular cup, as well as the clearance between the cup and head do change significantly the mechanical stresses experienced by a cemented UHMWPE acetabular cup. These factors should be taken into account in future development of THR prostheses. FE technique is a useful tool with which to address these issues. PMID:15904521

  11. Ultra high molecular weight polyethylene and polydimethylsiloxane blend as acetabular cup material.

    PubMed

    Khorasani, M T; Zaghiyan, M; Mirzadeh, H

    2005-03-25

    An acetabular cup shock absorber implant is formed from a composite of polymer materials. The cup consists of three zones such as the articulating surface of the implant is 100% ultra high molecular weight polyethylene (UHMWPE) (zone 1) and shock absorber of the cup contains of polydimethylsiloxane (PDMS) (zone 3). Zone 2 which is designed for better adhesion between zone 1 and zone 2 consists of a blend of UHMWPE and PDMS is a cushion that from one side adheres to zone 1 and the other side to zone 2. PDMS and UHMWPE have been blended under conditions of shear and elevated temperature in order to form uniform, thermoplastic blends. When blends compared to pure UHMWPE, the blends show lowered tensile modulus and lowered mixing energies. The UHMWPE crystals are increased in quantity or else become more regular, even 50% blend shows no rubbery stage. The morphology and dynamic mechanical behavior of the blends were studied using scanning electron microscopy (SEM) and dynamic mechanic thermal analysis (DMTA). In this study, the biocompatibility have evaluated in vitro the interaction of UHMWPE, silicone and PDMS/UHMWPE blends with L929 fibroblast cells.

  12. Osteoarthritis of the hip joint in elderly patients is most commonly atrophic, with low parameters of acetabular dysplasia and possible involvement of osteoporosis.

    PubMed

    Ishidou, Yasuhiro; Matsuyama, Kanehiro; Sakuma, Daisuke; Setoguchi, Takao; Nagano, Satoshi; Kawamura, Ichiro; Maeda, Shingo; Komiya, Setsuro

    2017-12-01

    As elderly patients with hip osteoarthritis aged, acetabular dysplasia parameters decreased (Sharp's angle, acetabular roof obliquity angle, and acetabular head index) and the incidence of the atrophic type increased. Vertebral body fracture was more frequent in the atrophic type, suggesting the involvement of osteoporosis at the onset of hip osteoarthritis. Osteoarthritis (OA) is associated with increased bone formation at a local site. However, excessive bone resorption has also been found to occur in the early stages of OA. Osteoporosis may be involved in the onset of OA in elderly patients. We conducted a cross-sectional radiographic study of patients with hip OA and examined the association between age and factors of acetabular dysplasia (Sharp's angle, acetabular roof obliquity angle, and acetabular head index) as well as the osteoblastic response to determine the potential involvement of osteoporosis. This study included 366 patients (58 men, 308 women) who had undergone total hip arthroplasty for the diagnosis of hip OA. We measured the parameters of acetabular dysplasia using preoperative frontal X-ray images and evaluated each patient according to Bombelli classification of OA (hypertrophic, normotrophic, or atrophic type). As the patients aged, the parameters of acetabular dysplasia decreased. The incidence of the atrophic type of OA was significantly higher in older patients. Vertebral body fractures were more frequent in the atrophic type than in the other types. Additionally, the index of acetabular dysplasia was lower in the atrophic type. By contrast, the hypertrophic type was present in relatively younger patients and was associated with an increased index of acetabular dysplasia. In elderly patients with hip OA, the parameters of acetabular dysplasia decreased and the incidence of the atrophic type increased as the patients aged. The frequency of vertebral body fracture was high in patients with the atrophic type, suggesting the involvement of

  13. Acetabular configuration and its impact on cup coverage of a subtype of Crowe type 4 DDH with bi-pseudoacetabulum.

    PubMed

    Yi, Chengqing; Ma, Chunhui; Wang, Qian; Zhang, Guoqiao; Cao, Yun

    2013-01-01

    The purpose of this study was to explore the acetabular configuration of a special subtype of Crowe type 4 DDH and its impact on cup coverage, which was identified with a particular bi-pseudoacetabulum and an inter-pseudoacetabulum spine structure. The altered bone stock and anatomic structures were believed to be a result of lesser trochanter impingement on the pelvis as observed in all hips of this series, which was supported by the radiographic and intraoperative findings. Acetabular characteristics were depicted by means of radiographic assessment and direct observation during surgery. Preoperatively, the horizontal distance to the hip centre was 80.5 mm on average and 52.9 mm for femoral head height with a significant difference compared to the general series of DDH cases. Anterosuperior bony coverage was found 
to be more adequate with a thicker anterior wall. The postoperative hip centre was restored to the true acetabulum to within 23.4 mm vertically and 25.2 mm horizontally, and sufficient cup containment was achieved when the acetabular inclination angle was below 45°. A larger diameter cup (range 46-50 mm) was employed. No structural bone graft was required, and the medial protrusion technique was infrequently required. This subtype of DDH facilitated cup coverage during THA.

  14. Trabecular metal cup without augments for acetabular revision in case of extensive bone loss and low bone-prosthesis contact.

    PubMed

    Pierannunzii, L; Mambretti, A; D'Imporzano, M

    2011-01-01

    Current evidences in revision hip arthroplasty suggest to treat severe acetabular bone loss with dedicated implants, such as anti-protrusio cages, stemmed cups, modular systems supplied with iliac flanges and obturatory hook. However recent literature is reporting satisfactory outcomes with simple elliptical Trabecular Metal cups. Purpose of the study was to evaluate mid-term results of such a surgical procedure. All hip revisions performed from 2008 to 2009 with implantation of a TMT multi-hole acetabular cup without augmentations were retrospectively reviewed. The cases with low-degree acetabular bone loss (stage I and II according to GIR classification), with surgical report poorly describing the bone defect, with inadequate pre- and post-operative x-rays were ruled out. Twenty-five cases were identified, but four were lost to follow-up. The twenty-one patients were 71 year-old on average (from 60 to 82), with stage IV bone loss in 6 cases and stage III bone loss in 15 cases. Mean interval from surgery to evaluation was 20.9 months (from 13 to 30). The evaluation included bone-prosthesis contact estimation, component position, survivorship, complications, final Harris Hip Score, presence of periprosthetic radiolucencies. Host bone-prosthesis contact was estimated to be about 35%. Only three implant were subsequently reoperated (for infection, early migration, recurrent dislocation). The HHS among non-reoperated 18 patients was 81.96 on average (from 63.44 to 95.82). Six cases showed thin radiolucencies in one of the three Charnley zones, while three cases showed radiolucencies in two. None of these images was evolutive, thus they were not considered signs of loosening. The mid-term results of this series confirm the hypothesis that a porous tantalum acetabular cup is an effective option to deal with difficult acetabular revisions. Although no extra-acetabular fixation device is available, the very high surface friction guaranteed by the material and the

  15. Al-Cu-Fe quasicrystal/ultra-high molecular weight polyethylene composites as biomaterials for acetabular cup prosthetics.

    PubMed

    Anderson, Brian C; Bloom, Paul D; Baikerikar, K G; Sheares, Valerie V; Mallapragada, Surya K

    2002-04-01

    Polymer composites of Al-Cu-Fe quasicrystals and ultra-high molecular weight polyethylene (UHMWPE) were investigated for use in acetabular cup prosthetics. The wear properties of the Al-Cu-Fe/UHMWPE samples and a 440 steel ball counterface were measured. The mechanical strength of the Al-Cu-Fe/UHMWPE composites was compared to UHMWPE and alumina/UHMWPE. The biocompatibility of the composite material was tested using a direct contact cytotoxicity assay. Al-Cu-Fe/UHMWPE demonstrated lower volume loss after wear and higher mechanical strength than UHMWPE. This composite material also showed no increase in counterface wear or cytotoxicity relative to UHMWPE. These combined results demonstrate that Al-Cu-Fe/UHMWPE composites are promising candidate materials for acetabular cup prosthetics.

  16. Morphological experimental study of bone stress at the interface acetabular bone/prosthetic cup in the bipolar hip prosthesis.

    PubMed

    Anuşca, D; Pleşea, I E; Iliescu, N; Tomescu, P; Poenaru, F; Dascălu, V; Pop, O T

    2006-01-01

    By calculating the tension and distortion of the elements composing the bipolar prosthesis under extreme conditions encountered in real life using a special post-processing program, we established the variation curves of the contact pressure at the hip bone-cup, armor-cup and cup-femoral head interface. By comparing the data obtained from all the examined cases, important conclusions were drawn regarding the influence of tension and pressure distribution on the structural integrity and biomechanics of the prosthesis, as well as the acetabular wear and tear, in order to assess its reliability. The experimentally determined tension and distortion status at the acetabular bone-metal armour interface, lead to the wear and tear phenomenon, which can be explained by three mechanisms and theories incompletely reflecting the overall process. The histopathologic study of the acetabular bone tissue using FEM (finite elements method) on surgically removed specimens will probably lead to the identification of a series of factors that could reduce the rate of the wear and tear process.

  17. The efficacy of a “double-D-shaped” wire marker for radiographic measurement of acetabular cup orientation and wear

    PubMed Central

    Derbyshire, Brian; Raut, Videshnandan V.

    2013-01-01

    Historically, wire markers were attached to cemented all-plastic acetabular cups to demarcate the periphery and to measure socket wear. The wire shape was either a semi-circle passing over the pole of the cup, or a circle around the cup equator. More recently, “double-D” shaped markers were introduced with a part-circular aspect passing over the pole and a semi-circular aspect parallel to the equatorial plane. This configuration enabled cup retroversion to be distinguished from anteversion. In this study, the accuracy of radiographic measurement of cup orientation and wear was assessed for cups with “double-D” and circular markers. Each cup was attached to a measurement jig which could vary the anteversion/retroversion and internal/external rotation of the cup. A metal femoral head was fixed within the socket and radiographic images were created for all combinations of cup orientation settings. The images were measured using software with automatic edge detection, and cup orientation and zero-wear accuracies were determined for each setting. The median error for cup version measurements was similar for both types of wire marker (0.2° double-D marker, −0.24° circular marker), but measurements of the circular marker were more repeatable. The median inclination errors were 2.05° (double-D marker) and 0.23° (circular marker). The median overall “zero wear” errors were 0.19 mm (double-D marker) and 0.03 mm (circular marker). Measurements of the circular wire marker were much more repeatable. PMID:23813165

  18. Does Robotic-Assisted Computer Navigation Affect Acetabular Cup Positioning in Total Hip Arthroplasty in the Obese Patient? A Comparison Study.

    PubMed

    Gupta, Asheesh; Redmond, John M; Hammarstedt, Jon E; Petrakos, Alexandra E; Vemula, S Pavan; Domb, Benjamin G

    2015-12-01

    Obese populations present challenges for acetabular cup placement during total hip arthroplasty (THA). This study examines the accuracy of acetabular cup inclination and version in the obese patient with robotic-assisted computer navigation. A total of 105 patients underwent robotic-assisted computer navigation THA with a posterior approach. Groups were divided on body mass index (BMI, kg/m(2)) of <30, 30-35, and >35. There was no statistical difference between the BMI <30 (n=59), BMI 30-35 (n=34) and BMI >35 (n=12) groups for acetabular inclination (P=0.43) or version (P=0.95). Robotic-assisted computer navigation provided accurate and reproducible placement of the acetabular cup within safe zones for inclination and version in the obese patient. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Increased migration of uncemented acetabular cups in female total hip arthroplasty patients with low systemic bone mineral density

    PubMed Central

    Finnilä, Sami; Moritz, Niko; SvedströM, Erkki; Alm, Jessica J; Aro, Hannu T

    2016-01-01

    Background and purpose Low bone mineral density (BMD) may jeopardize the initial component stability and delay osseointegration of uncemented acetabular cups in total hip arthroplasty (THA). We measured the migration of uncemented cups in women with low or normal BMD. Patients and methods We used radiostereometric analysis (RSA) to measure the migration of hydroxyapatite-coated titanium alloy cups with alumina-on-alumina bearings in THA of 34 female patients with a median age of 64 (41–78) years. 10 patients had normal BMD and 24 patients had low systemic BMD (T-score ≤ −1) based on dual-energy X-ray absorptiometry (DXA). Cup migration was followed with RSA for 2 years. Radiographic follow-up was done at a median of 8 (2–10) years. Results Patients with normal BMD did not show a statistically significant cup migration after the settling period of 3 months, while patients with low BMD had a continuous proximal migration between 3 and 12 months (p = 0.03). These differences in cup migration persisted at 24 months. Based on the perceived risk of cup revision, 14 of the 24 cases were “at risk” (proximal translation of 0.2 to 1.0 mm) in the low-BMD group and 2 of the10 cases were “at risk” in the normal-BMD group (odds ratio (OR) = 8.0, 95% CI: 1.3–48). The radiographic follow-up showed no radiolucent lines or osteolysis. 2 cups have been revised for fractures of the ceramic bearings, but none for loosening. Interpretation Low BMD contributed to cup migration beyond the settling period of 3 months, but the migrating cups appeared to osseointegrate eventually. PMID:26569616

  20. Acetabular labrum blood flow in developmental dysplasia of the hip: an intraoperative in vivo study using laser Doppler flowmetry.

    PubMed

    Minokawa, So; Naito, Masatoshi; Kinoshita, Koichi; Yamamoto, Takuaki

    2016-10-17

    The vascular supply to the acetabular labrum is important in the treatment of labral lesions. However, in vivo blood flow measurements in the acetabular labrum have not been described in the literature. The purpose of this study was to examine this blood flow in vivo using laser Doppler flowmetry (LDF) in patients with acetabular dysplasia. Periacetabular osteotomy combined with arthroscopy was performed in 47 consecutive patients (three males, 44 females; mean age at surgery, 35.6 years; range, 15-60 years). In all patients, blood flow in the acetabular labrum was measured with LDF during arthroscopy. The acetabular labral lesions were categorized according to the modified Beck classification: detachment and full-thickness labral tears were assigned to the T group and normal labrum to the N group. Blood flow rates in the acetabular labrum were compared between the T and N groups. The associations between labral blood flow and the lateral center-edge angle (CEa) and patient age were also evaluated. The T and N groups comprised 31 and 16 patients, respectively. The mean blood flow rate was 1.94 ± 0.41 ml/min/100 g in the T group and 1.94 ± 0.34 ml/min/100 g in the N group, with no significant difference between the groups (P = 0.884). No association was noted between blood flow and either the CEa or patient age (β = -0.018, P = 0.077 and β = -0.001, P = 0.770, respectively). On LDF, blood flow in the acetabular labrum was present in all patients, regardless of the severity of acetabular labral tears, CEa, or age.

  1. The use of a "rim cutter" device and a flanged cup for improving the mantle of the acetabular component of a cemented Exeter total hip arthroplasty.

    PubMed

    Fernández-Valencia, Jenaro Ángel; Gallart, Xavier; Bori, Guillem; Rodríguez-Roiz, Juan Miguel; Combalia, Andreu

    2016-12-01

    A retrospective study was performed to evaluate the cement mantle in two groups of patients treated with the acetabular components of cemented Exeter total hip arthroplasties (THAs). Two groups of 20 patients were compared: Group 1 received non-flanged acetabular cemented cups (Contemporary, Stryker) and Group 2 received flanged acetabular cemented cups (X3 Rim Fit, Stryker). Cups in Group 2 were implanted after using a rim cutter device. Group 2 showed better penetration of cement in zone 1 (10.76 mm compared with 2.93 mm; p = 0.008) and a thicker cement mantle in zone 1 (3.57 mm compared with 2.89 mm; p = 0.04). More cups in Group 2 had a cement mantle thickness less than 3 mm (30 % in Group 1 compared with 70 % in Group 2; p = 0.0039). No other radiological differences were observed. These results favor the use of a rim cutter device and flanged cup to improve the cement mantle for the acetabular components of cemented Exeter THAs. However, the improvements were less than expected. In view of the results of previous studies, further research is therefore needed to assess the value of this approach in improving the acetabular cement mantle.

  2. Quantification of Wear and Deformation in Different Configurations of Polyethylene Acetabular Cups Using Micro X-ray Computed Tomography.

    PubMed

    Affatato, Saverio; Zanini, Filippo; Carmignato, Simone

    2017-03-03

    Wear is currently quantified as mass loss of the bearing materials measured using gravimetric methods. However, this method does not provide other information, such as volumetric loss or surface deviation. In this work, we validated a technique to quantify polyethylene wear in three different batches of ultrahigh-molecular-polyethylene acetabular cups used for hip implants using nondestructive microcomputed tomography. Three different configurations of polyethylene acetabular cups, previously tested under the ISO 14242 parameters, were tested on a hip simulator for an additional 2 million cycles using a modified ISO 14242 load waveform. In this context, a new approach was proposed in order to simulate, on a hip joint simulator, high-demand activities. In addition, the effects of these activities were analyzed in terms of wear and deformations of those polyethylenes by means of gravimetric method and micro X-ray computed tomography. In particular, while the gravimetric method was used for weight loss assessment, microcomputed tomography allowed for acquisition of additional quantitative information about the evolution of local wear and deformation through three-dimensional surface deviation maps for the entire cups' surface. Experimental results showed that the wear and deformation behavior of these materials change according to different mechanical simulations.

  3. The Divergence of Wear Propagation and Stress at Steep Acetabular Cup Positions Using Ceramic Heads and Sequentially Cross-Linked Polyethylene Liners.

    PubMed

    Zietz, Carmen; Fabry, Christian; Baum, Felix; Bader, Rainer; Kluess, Daniel

    2015-08-01

    The aim of the present wear simulator study was to assess the effect of steep acetabular cup positions on the wear propagation of highly cross-linked-PE (HX-PE) liners. Furthermore, a finite element analysis (FEA) was performed in order to calculate the stress within the HX-PE material in case of steep cup positions under physiological loadings. The higher stress in the HX-PE at a steep acetabular cup position did not result in increased wear in the present wear simulator study. The gravimetrical wear rates at normal (45°) and steep cup inclinations (75°) showed wear amounts of 3.15±0.27mg and 2.18±0.31mg per million cycles (p=0.028), respectively. However, FEA revealed clear increase in stress at the HX-PE liners with respect to steep cup positions.

  4. Assessing the Acetabular Cup Implant Primary Stability by Impact Analyses: A Cadaveric Study

    PubMed Central

    Michel, Adrien; Bosc, Romain; Meningaud, Jean-Paul; Hernigou, Philippe; Haiat, Guillaume

    2016-01-01

    Background The primary stability of the acetabular cup (AC) implant is an important determinant for the long term success of cementless hip surgery. However, it remains difficult to assess the AC implant stability due to the complex nature of the bone-implant interface. A compromise should be found when inserting the AC implant in order to obtain a sufficient implant stability without risking bone fracture. The aim of this study is to evaluate the potential of impact signals analyses to assess the primary stability of AC implants inserted in cadaveric specimens. Methods AC implants with various sizes were inserted in 12 cadaveric hips following the same protocol as the one employed in the clinic, leading to 86 different configurations. A hammer instrumented with a piezoelectric force sensor was then used to measure the variation of the force as a function of time produced during the impact between the hammer and the ancillary. Then, an indicator I was determined for each impact based on the impact momentum. For each configuration, twelve impacts were realized with the hammer, the value of the maximum amplitude being comprised between 2500 and 4500 N, which allows to determine an averaged value IM of the indicator for each configuration. The pull-out force F was measured using a tangential pull-out biomechanical test. Results A significant correlation (R2 = 0.69) was found between IM and F when pooling all data, which indicates that information related to the AC implant biomechanical stability can be retrieved from the analysis of impact signals obtained in cadavers. Conclusion These results open new paths in the development of a medical device that could be used in the future in the operative room to help orthopedic surgeons adapt the surgical protocol in a patient specific manner. PMID:27893757

  5. Assessment of Accuracy and Reliability in Acetabular Cup Placement Using an iPhone/iPad System.

    PubMed

    Kurosaka, Kenji; Fukunishi, Shigeo; Fukui, Tomokazu; Nishio, Shoji; Fujihara, Yuki; Okahisa, Shohei; Takeda, Yu; Daimon, Takashi; Yoshiya, Shinichi

    2016-07-01

    Implant positioning is one of the critical factors that influences postoperative outcome of total hip arthroplasty (THA). Malpositioning of the implant may lead to an increased risk of postoperative complications such as prosthetic impingement, dislocation, restricted range of motion, polyethylene wear, and loosening. In 2012, the intraoperative use of smartphone technology in THA for improved accuracy of acetabular cup placement was reported. The purpose of this study was to examine the accuracy of an iPhone/iPad-guided technique in positioning the acetabular cup in THA compared with the reference values obtained from the image-free navigation system in a cadaveric experiment. Five hips of 5 embalmed whole-body cadavers were used in the study. Seven orthopedic surgeons (4 residents and 3 senior hip surgeons) participated in the study. All of the surgeons examined each of the 5 hips 3 times. The target angle was 38°/19° for operative inclination/anteversion angles, which corresponded to radiographic inclination/anteversion angles of 40°/15°. The simultaneous assessment using the navigation system showed mean±SD radiographic alignment angles of 39.4°±2.6° and 16.4°±2.6° for inclination and anteversion, respectively. Assessment of cup positioning based on Lewinnek's safe zone criteria showed all of the procedures (n=105) achieved acceptable alignment within the safe zone. A comparison of the performances by resident and senior hip surgeons showed no significant difference between the groups (P=.74 for inclination and P=.81 for anteversion). The iPhone/iPad technique examined in this study could achieve acceptable performance in determining cup alignment in THA regardless of the surgeon's expertise. [Orthopedics. 2016; 39(4):e621-e626.].

  6. Impact biomechanics and pelvic deformation during insertion of press-fit acetabular cups.

    PubMed

    Kroeber, Markus; Ries, Michael D; Suzuki, Yoshihiro; Renowitzky, Glen; Ashford, Frank; Lotz, Jeff

    2002-04-01

    Five fresh cadaver pelves were cleaned of soft tissue and instrumented with strain gauges. The acetabula were reamed, and a cementless cup, oversized at the periphery, was inserted. The applied force and cup acceleration were measured during insertion and used to calculate an effective mass of the cup, insertion device, and pelvis during each impact. Periacetabular strains increased variably during cup seating. After the cups were seated, strains continued to increase with postseating impacts. The effective mass remained constant throughout the test, indicating that cup seating is not associated with a change in acceleration. This finding implies that an accurate assessment of cup seating cannot be inferred by surgeon proprioception during impaction, and use of an apical hole in the cup is necessary to determine when the cup has seated.

  7. Quantification of Wear and Deformation in Different Configurations of Polyethylene Acetabular Cups Using Micro X-ray Computed Tomography

    PubMed Central

    Affatato, Saverio; Zanini, Filippo; Carmignato, Simone

    2017-01-01

    Wear is currently quantified as mass loss of the bearing materials measured using gravimetric methods. However, this method does not provide other information, such as volumetric loss or surface deviation. In this work, we validated a technique to quantify polyethylene wear in three different batches of ultrahigh-molecular-polyethylene acetabular cups used for hip implants using nondestructive microcomputed tomography. Three different configurations of polyethylene acetabular cups, previously tested under the ISO 14242 parameters, were tested on a hip simulator for an additional 2 million cycles using a modified ISO 14242 load waveform. In this context, a new approach was proposed in order to simulate, on a hip joint simulator, high-demand activities. In addition, the effects of these activities were analyzed in terms of wear and deformations of those polyethylenes by means of gravimetric method and micro X-ray computed tomography. In particular, while the gravimetric method was used for weight loss assessment, microcomputed tomography allowed for acquisition of additional quantitative information about the evolution of local wear and deformation through three-dimensional surface deviation maps for the entire cups’ surface. Experimental results showed that the wear and deformation behavior of these materials change according to different mechanical simulations. PMID:28772616

  8. Inter- and intra-observer variability of radiography and computed tomography for evaluation of Zurich cementless acetabular cup placement ex vivo.

    PubMed

    Leasure, Jessica O; Peck, Jeffrey N; Villamil, Armando; Fiore, Kara L; Tano, Cheryl A

    2016-11-23

    To evaluate the inter- and intra-observer variability in measurement of the angle of lateral opening (ALO) and version angle measurement using digital radiography and computed tomography (CT). Each hemipelvis was implanted with a cementless acetabular cup. Ventrodorsal and mediolateral radiographs were made of each pelvis, followed by CT imaging. After removal of the first cup, the pelves were implanted with an acetabular cup in the contralateral acetabulum and imaging was repeated. Three surgeons measured the ALO and version angles three times for each cup from the mediolateral radiographic projection. The same measurements were made using three-dimensional multiplanar reconstructions from CT images. Two anatomical axes were used to measure pelvic inclination in the sagittal plane, resulting in six measurements per cup. Two-way repeated measures analysis of variance evaluated inter- and intra-observer repeatability for radiographic and CT-based measurements. Version angle based on radiographic measurement did not differ within surgeons (p = 0.433), but differed between surgeons (p <0.001). Radiographic measurement of ALO differed within surgeons (p = 0.006) but not between surgeons (p = 0.989). The ALO and version angle measured on CT images did not differ with or between surgeons. Assessment of inter- and intra-observer measurement of ALO and version angle was more reproducible using CT images than conventional mediolateral radiography for a Zurich cementless acetabular cup.

  9. [Evaluation of acetabular cup placement precision in Stryker computer-assisted navigated total hip arthroplasty].

    PubMed

    Shang, Peng; Bai, Xueling; Shi, Dufang

    2012-09-01

    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.

  10. Comparison of robotic-assisted and conventional acetabular cup placement in THA: a matched-pair controlled study.

    PubMed

    Domb, Benjamin G; El Bitar, Youssef F; Sadik, Adam Y; Stake, Christine E; Botser, Itamar B

    2014-01-01

    Improper acetabular component orientation in THA has been associated with increased dislocation rates, component impingement, bearing surface wear, and a greater likelihood of revision. Therefore, any reasonable steps to improve acetabular component orientation should be considered and explored. We therefore sought to compare THA with a robotic-assisted posterior approach with manual alignment techniques through a posterior approach, using a matched-pair controlled study design, to assess whether the use of the robot made it more likely for the acetabular cup to be positioned in the safe zones described by Lewinnek et al. and Callanan et al. Between September 2008 and September 2012, 160 THAs were performed by the senior surgeon. Sixty-two patients (38.8%) underwent THA using a conventional posterior approach, 69 (43.1%) underwent robotic-assisted THA using the posterior approach, and 29 (18.1%) underwent radiographic-guided anterior-approach THAs. From September 2008 to June 2011, all patients were offered anterior or posterior approaches regardless of BMI and anatomy. Since introduction of the robot in June 2011, all THAs were performed using the robotic technique through the posterior approach, unless a patient specifically requested otherwise. The radiographic cup positioning of the robotic-assisted THAs was compared with a matched-pair control group of conventional THAs performed by the same surgeon through the same posterior approach. The safe zone (inclination, 30°-50°; anteversion, 5°-25°) described by Lewinnek et al. and the modified safe zone (inclination, 30°-45°; anteversion, 5°-25°) of Callanan et al. were used for cup placement assessment. Matching criteria were gender, age ± 5 years, and (BMI) ± 7 units. After exclusions, a total of 50 THAs were included in each group. Strong interobserver and intraobserver correlations were found for all radiographic measurements (r > 0.82; p < 0.001). One hundred percent (50/50) of the robotic

  11. Oxidation in ultrahigh molecular weight polyethylene and cross-linked polyethylene acetabular cups tested against roughened femoral heads in a hip joint simulator.

    PubMed

    Taddei, Paola; Affatato, Saverio; Fagnano, Concezio; Toni, Aldo

    2006-06-01

    This study was aimed at comparing the oxidative degradation of commercial acetabular cups made of cross-linked polyethylene (XLPE) and conventional ultrahigh molecular weight polyethylene (UHMWPE). After testing against deliberately scratched CoCrMo femoral heads in a hip joint simulator, the cups, microtomed parallel to the articulating surface, were analyzed by IR spectroscopy. Due to the potential for artifacts caused by absorbed contaminants, the IR spectra were compared only after hexane extraction; actually, XLPE was found to absorb more serum than UHMWPE. The two sets of unworn acetabular cups showed different oxidation patterns with consequently different distributions of carbonyl species; unworn XLPE was characterized by lower contents of carbonyl species and hydrogen-bonded alcohols and higher contents of trans-vinylene species than unworn UHMWPE. Upon simulator testing, UHMWPE showed more significant changes in oxidation indexes and distribution of carbonyl compounds than XLPE, confirming a better wear behavior for XLPE under the adopted testing conditions.

  12. Surgical Treatment of Adolescent Acetabular Dysplasia With a Periacetabular Osteotomy: Does Obesity Increase the Risk of Complications?

    PubMed

    Novais, Eduardo N; Potter, Gorden D; Sierra, Rafael J; Kim, Young-Jo; Clohisy, John C; Schoenecker, Perry L; Trousdale, Robert T; Carry, Patrick M; Millis, Michael B

    2015-09-01

    The Bernese periacetabular osteotomy (PAO) is frequently used to treat symptomatic acetabular dysplasia in the adolescent age group. Despite encouraging results, factors predictive of the development of postoperative complications remain poorly understood. The purpose of this study was to investigate whether obesity is a risk factor for complications following PAO in adolescents. A retrospective cohort study design was used to collect data from 3 different institutions. Children and adolescents (below 19 y of age) who underwent PAO and were followed for minimum of 12 months were included. Obesity was defined as a body mass index ≥95 percentile. The modified Clavien-Dindo classification was used to grade complications. A logistic regression analysis was used to identify factors related to the development of a complication that required treatment outside of routine postoperative care (complication grades II to V). Changes in radiographic parameters including Tönnis acetabular roof angle, anterior center-edge angle, and lateral center-edge angle among obese versus nonobese subjects were also evaluated. The mean age at surgery among the 84 adolescents included in the study was 16.5 years (range, 12 to 19 y). A total of 11% of the population was considered obese. Obesity (P=0.0047) was the only variable significantly associated with the development of a complication. After controlling for study site, the odds of an obese subject developing a complication were 10 [95% confidence interval (CI), 1.89-59.8] times the odds of a nonobese subject developing a complication. There was no difference in the magnitude of change in anterior center-edge angle (P=0.1251), lateral center-edge angle (P=0.9774), or Tönnis (P=0.5770) angular correction that was achieved among the obese versus nonobese subjects following surgery. The Bernese PAO allows for adequate radiographic correction of acetabular dysplasia among obese and nonobese adolescents. However, the hip preservation

  13. Dilemmas in imaging for peri-acetabular osteotomy: the influence of patient position and imaging technique on the radiological features of hip dysplasia.

    PubMed

    Kosuge, D; Cordier, T; Solomon, L B; Howie, D W

    2014-09-01

    Peri-acetabular osteotomy is an established surgical treatment for symptomatic acetabular dysplasia in young adults. An anteroposterior radiograph of the pelvis is commonly used to assess the extent of dysplasia as well as to assess post-operative correction. Radiological prognostic factors include the lateral centre-edge angle, acetabular index, extrusion index and the acetabular version. Standing causes a change in the pelvis tilt which can alter certain radiological measurements relative to the supine position. This article discusses the radiological indices used to assess dysplasia and reviews the effects of patient positioning on these indices with a focus on assessment for a peri-acetabular osteotomy. Intra-operatively, fluoroscopy is commonly used and the implications of using fluoroscopy as a modality to assess the various radiological indices along with the effects of using an anteroposterior or posteroanterior fluoroscopic view are examined. Each of these techniques gives rise to a slightly different image of the pelvis as the final image is sensitive to the position of the pelvis and the projection of the x-ray beam.

  14. [Acetabular Osteolysis in Total Hip Replacement - When to Retain the Cup?].

    PubMed

    Lutz, B; Faschingbauer, M; Bieger, R; Reichel, H; Kappe, T

    2016-08-01

    Periacetabular osteolysis is a frequent long-term complication of cementless total hip arthroplasty. The decision whether to retain or to revise a cup in the presence of osteolysis remains a challenge. The options are regular clinical and radiological check-ups, isolated liner exchange with and without bone grafting, and complete cup revision. Thorough preoperative diagnostics, including a medical history, examination and imaging, are mandatory for correct decision making. In most patients, computed tomography is useful to assess periacetabular osteolysis. If the cup is well-fixed and positioned in an asymptomatic patient without progressive osteolysis and no implant defect or higher grade polyethylene wear and no signs of infection, continuous clinical and radiological monitoring is preferred. If imaging reveals cup loosening, malposition, osteolysis localised in a weight-bearing area, imminent or present periprosthetic fractures, rapid progressive osteolysis, implant defects or massive inlay wear, surgical treatment may be preferred. Cup revision is usually performed in such patients. If the cup is well-positioned and well-fixed in the X-ray, the procedure has to be discussed with the patient individually. Apart from patient-specific risk factors, the risk of further progression has to be assessed. Isolated liner exchange can be performed if the patient is asymptomatic and the cup proves to be stable intraoperatively. It is still unclear whether filling osteolyses through screw holes or osseous windows is of long-term benefit. Georg Thieme Verlag KG Stuttgart · New York.

  15. Does osteoporosis reduce the primary tilting stability of cementless acetabular cups?

    PubMed

    von Schulze Pellengahr, Christoph; von Engelhardt, Lars V; Wegener, Bernd; Müller, Peter E; Fottner, Andreas; Weber, Patrick; Ackermann, Ole; Lahner, Matthias; Teske, Wolfram

    2015-04-21

    Cementless hip cups need sufficient primary tilting stability to achieve osseointegration. The aim of the study was to assess differences of the primary implant stability in osteoporotic bone and in bone with normal bone density. To assess the influence of different cup designs, two types of threaded and two types of press-fit cups were tested. The maximum tilting moment for two different cementless threaded cups and two different cementless press-fit cups was determined in macerated human hip acetabuli with reduced (n=20) and normal bone density (n=20), determined using Q-CT. The tilting moments for each cup were determined five times in the group with reduced bone density and five times in the group with normal bone density, and the respective average values were calculated. The mean maximum extrusion force of the threaded cup Zintra was 5670.5 N (max. tilting moment 141.8 Nm) in bone with normal density and.5748.3 N (max. tilting moment 143.7 Nm) in osteoporotic bone. For the Hofer Imhof (HI) threaded cup it was 7681.5 N (192.0 Nm) in bone with normal density and 6828.9 N (max. tilting moment 170.7 Nm) in the group with osteoporotic bone. The mean maximum extrusion force of the macro-textured press-fit cup Metallsockel CL was 3824.6 N (max. tilting moment 95.6 Nm) in bone with normal and 2246.2 N (max. tilting moment 56.2 Nm) in osteoporotic bone. For the Monoblock it was 1303.8 N (max. tilting moment 32.6 Nm) in normal and 1317 N (max. tilting moment 32.9 Nm) in osteoporotic bone. There was no significance. A reduction of the maximum tilting moment in osteoporotic bone of the ESKA press-fit cup Metallsockel CL was noticed. Results on macerated bone specimens showed no statistically significant reduction of the maximum tilting moment in specimens with osteoporotic bone density compared to normal bone, neither for threaded nor for the press-fit cups. With the limitation that the results were obtained using macerated bone, we could not detect any restrictions for

  16. Cup positioning in total hip arthoplasty: spatial alignment of the acetabular entry plane.

    PubMed

    Wohlrab, David; Radetzki, Florian; Noser, Hansrudi; Mendel, Thomas

    2012-01-01

    Correct cup positioning is one of the keys for successful total hip replacement. There are mechanical and computer assistant guides for correct cup positioning in the market. To optimize the cup positioning, the use of navigation systems is recommended. The aim of this study was to compare spatial orientation of the acetabulary entry plane in relation to tables plane which is used by mechanical guides as well as anterior pelvic plane used for cup orientation by navigation systems. CT raw data of 80 Caucasians (160 acetabuli) (done in supine position) with osteoartritic hips were collected. 3-D pelvic reconstruction was generated using Amira software (Visage Imaging Berlin, Germany). Anterior pelvic plane and acetabulary entry plane were defined by reliable anatomical landmarks. Spatial orientation were calculated by a custom made program code for the Amira software. There were no differences between anterior pelvic plane and table's plane as well as spatial orientation of acetabulary entry plane of both acetabuli in relation to anterior pelvic plane or table's plane. Furthermore, there was no correlation between age, sex or body mass index and spatial orientation of the acetabulary entry plane as well. The use of mechanical alignment guides for cup orientation during total hip arthroplasty based on table's plane in patient's supine position is a successful method to achieve proper cup orientation.

  17. Structural profile of ultra-high molecular weight polyethylene in acetabular cups worn on hip simulators characterized by confocal Raman spectroscopy.

    PubMed

    Puppulin, Leonardo; Kumakura, Tsuyoshi; Yamamoto, Kengo; Pezzotti, Giuseppe

    2011-06-01

    We applied a Raman confocal spectroscopic technique to quantitatively assess the structural features of two kinds of acetabular cups made of ultra-high molecular weight polyethylene. We wanted to know whether polyethylene cups belonging to different generations, and thus manufactured by different procedures, possess different molecular structures and how those differences affected their wear resistance. Emphasis was placed on oxidation profiles developed along the cross-sectional depth of the cups in the main wear zone developed during testing in a hip simulator. The micrometric lateral resolution of the laser beam, focused at surface or sub-surface sectional planes, enabled the visualization of highly resolved microstructural property profiles, including crystalline and amorphous phase fractions. Oxidation profiles retrieved from polyethylene cups belonging to different generations greatly differed after wear testing. The highly cross-linked polyethylene showed a lower degree of crystallinity and oxidation at an appreciably slower rate as compared to that belonging to an earlier generation.

  18. Relationship between Wiberg's lateral center edge angle, Lequesne's acetabular index, and medial acetabular bone stock.

    PubMed

    Werner, Clément M L; Copeland, Carol E; Ruckstuhl, Thomas; Stromberg, Jeff; Turen, Clifford H; Bouaicha, Samy

    2011-11-01

    Knowledge of acetabular anatomy is crucial for cup positioning in total hip replacement. Medial wall thickness of the acetabulum is known to correlate with the degree of developmental dysplasia of the hip (DDH). No data exist about the relationship of routinely used radiographic parameters such as Wiberg's lateral center edge angle (LCE-angle) or Lequesne's acetabular index (AI) with thickness of the medial acetabular wall in the general population. The aim of our study was to clarify the relationship between LCE, AI, and thickness of the medial acetabular wall. Measurements on plain radiographs (LCE and AI) and axial CT scans (quadrilateral plate acetabular distance QPAD) of 1,201 individuals (2,402 hips) were obtained using a PACS imaging program and statistical analyses were performed. The mean thickness of the medial acetabulum bone stock (QPAD) was 1.08 mm (95% CI: 1.05-1.10) with a range of 0.1 to 8.8 mm. For pathological values of either the LCE (<20°) or the AI (>12°) the medial acetabular wall showed to be thicker than in radiological normal hips. The overall correlation between coxometric indices and medial acetabular was weak for LCE (r =-0.21. 95% CI [-0.25, -0.17]) and moderate for AI (r = 0.37, [0.33, 0.41]). We did not find a linear relationship between Wiberg's lateral center edge angle, Lequesne's acetabular index and medial acetabular bone stock in radiological normal hips but medial acetabular wall thickness increases with dysplastic indices.

  19. Two-dimensional and three-dimensional cup coverage in total hip arthroplasty with developmental dysplasia of the hip.

    PubMed

    Wang, Liao; Thoreson, Andrew R; Trousdale, Robert T; Morrey, Bernard F; Dai, Kerong; An, Kai-Nan

    2013-06-21

    We analyzed the mean difference and correlation between 2D cup coverage measured from different projections and three-dimensional (3D) cup coverage to investigate their precise relationship in total hip arthroplasty (THA) among patients with developmental dysplasia of the hip (DDH). We created DDH-THA models on six foam pelvic models. 3D cup coverage was measured using a motion capture system and imaging software. Digitally reconstructed radiographs with predetermined pelvic rotations were simulated using image processing software at three different angles of rotation around the long body axis (0°, 25° and 45°). 2D cup coverage was then measured on these reconstructed radiographs. The 3D technique showed excellent intra-observer (κ>0.98) and inter-observer (κ>0.99) reliability. The 2D technique tended to overestimate the real cup coverage by about 15%. The smallest difference between 2D and 3D cup coverage occurred when 2D measurement was performed on the radiographs with 45° of pelvic rotation toward the operated side (14.50%, P<0.0001), meanwhile, the highest correlation coefficient between 2D and 3D cup coverage was also observed when the 2D measurement was performed on the radiographs at this same pelvic rotation (r=0.67, P=0.0003). Published recommendations regarding the minimum cup coverage based on 2D measurement should be interpreted cautiously. The minimal cup coverage, as an intra-operative 3D parameter related to the long term fixation of the cup component, should be more accurately determined with intra-operative measurement.

  20. Radiostereometric analysis study of tantalum compared with titanium acetabular cups and highly cross-linked compared with conventional liners in young patients undergoing total hip replacement.

    PubMed

    Ayers, David C; Greene, Meridith; Snyder, Benjamin; Aubin, Michelle; Drew, Jacob; Bragdon, Charles

    2015-04-15

    Radiostereometric analysis provides highly precise measurements of component micromotion relative to the bone that is otherwise undetectable by routine radiographs. This study compared, at a minimum of five years following surgery, the micromotion of tantalum and titanium acetabular cups and femoral head penetration in highly cross-linked polyethylene liners and conventional (ultra-high molecular weight polyethylene) liners in active patients who had undergone total hip replacement. This institutional review board-approved prospective, randomized, blinded study involved forty-six patients. Patients were randomized into one of four cohorts according to both acetabular cup and polyethylene liner. Patients received either a cementless cup with a titanium mesh surface or a tantalum trabecular surface and either a highly cross-linked polyethylene liner or an ultra-high molecular weight polyethylene liner. Radiostereometric analysis examinations and Short Form-36 Physical Component Summary, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), University of California Los Angeles (UCLA) activity, and Harris hip scores were obtained preoperatively, postoperatively, at six months, and annually thereafter. All patients had significant improvement (p < 0.05) in Short Form-36 Physical Component Summary, WOMAC, UCLA activity, and Harris hip scores postoperatively. On radiostereometric analysis examination, highly cross-linked polyethylene liners showed significantly less median femoral head penetration at five years (p < 0.05). Steady-state wear rates from one year to five years were 0.04 mm per year for ultra-high molecular weight polyethylene liners and 0.004 mm per year for highly cross-linked polyethylene liners. At the five-year follow-up, the median migration (and standard error) was 0.05 ± 0.20 mm proximally for titanium cups and 0.21 ± 0.05 mm for tantalum cups. In this young population who had undergone total hip replacement, radiostereometric

  1. Radiostereometric Analysis Study of Tantalum Compared with Titanium Acetabular Cups and Highly Cross-Linked Compared with Conventional Liners in Young Patients Undergoing Total Hip Replacement

    PubMed Central

    Ayers, David C.; Greene, Meridith; Snyder, Benjamin; Aubin, Michelle; Drew, Jacob; Bragdon, Charles

    2015-01-01

    Background: Radiostereometric analysis provides highly precise measurements of component micromotion relative to the bone that is otherwise undetectable by routine radiographs. This study compared, at a minimum of five years following surgery, the micromotion of tantalum and titanium acetabular cups and femoral head penetration in highly cross-linked polyethylene liners and conventional (ultra-high molecular weight polyethylene) liners in active patients who had undergone total hip replacement. Methods: This institutional review board-approved prospective, randomized, blinded study involved forty-six patients. Patients were randomized into one of four cohorts according to both acetabular cup and polyethylene liner. Patients received either a cementless cup with a titanium mesh surface or a tantalum trabecular surface and either a highly cross-linked polyethylene liner or an ultra-high molecular weight polyethylene liner. Radiostereometric analysis examinations and Short Form-36 Physical Component Summary, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), University of California Los Angeles (UCLA) activity, and Harris hip scores were obtained preoperatively, postoperatively, at six months, and annually thereafter. Results: All patients had significant improvement (p < 0.05) in Short Form-36 Physical Component Summary, WOMAC, UCLA activity, and Harris hip scores postoperatively. On radiostereometric analysis examination, highly cross-linked polyethylene liners showed significantly less median femoral head penetration at five years (p < 0.05). Steady-state wear rates from one year to five years were 0.04 mm per year for ultra-high molecular weight polyethylene liners and 0.004 mm per year for highly cross-linked polyethylene liners. At the five-year follow-up, the median migration (and standard error) was 0.05 ± 0.20 mm proximally for titanium cups and 0.21 ± 0.05 mm for tantalum cups. Conclusions: In this young population who had undergone

  2. [Ceramic acetabular cups for hip endoprostheses. 7: How do position of the center of rotation and the CCD angle of the shaft modify range of motion and impingement?].

    PubMed

    Bader, R; Willmann, G

    1999-12-01

    The range of motion (ROM) of total hip prostheses is influenced by a number of parameters. An insufficient ROM may cause impingement, which may result in subluxation, dislocation or material failure of the prostheses. In a three-dimensional CAD simulation, the position of the centre of rotation and the CCD angle of the stem were investigated. Displacement of the centre of rotation of the femoral head may be due to wear (PE cups) or to the design of the prosthesis (ceramic cups). Stems of widely differing design have been developed and implanted. The results of the present study demonstrate that the ROM is clearly reduced by increasing penetration of the femoral head. At an inclination angle of 45 degrees, a depth of penetration of 2 mm restricts flexion by about 15 degrees, and a depth of penetration of 3 mm by about 30 degrees. At smaller angles of inclination the ROM is reduced and flexion and abduction are associated with an increased risk of impingement. With steeper acetabular cup inclinations, the risk of impingement decreases, but dislocation, the risk of rim fractures (ceramic cups), and wear and penetration rates (PE cups) increase. The CCD angle of the stem should be oriented to the anatomical situation. At high CCD angles (> 135 degrees), flexion is clearly limited, in particular when there is penetration of the femoral head. For modern total hip arthroplasty, prosthetic systems characterised by precise positioning of components, minimum wear, slightly recessed inserts, and appropriate CCD angles should be used.

  3. Hip arthroscopy in patients with recurrent pain following Bernese periacetabular osteotomy for acetabular dysplasia: operative findings and clinical outcomes.

    PubMed

    Cvetanovich, Gregory L; Heyworth, Benton E; Murray, Kerri; Yen, Yi-Meng; Kocher, Mininder S; Millis, Michael B

    2015-10-01

    To report the operative findings and outcomes of hip arthroscopy for recurrent pain following periacetabular osteotomy (PAO) for acetabular dysplasia. A departmental database was used to identify patients who underwent hip arthroscopy following PAO between 2000 and 2009. Demographic data, arthroscopic findings, functional outcome scores and patient satisfaction were analysed. Of 556 PAO patients, 17 hips in 16 patients (3.1%) underwent post-PAO hip arthroscopy. Mean age at PAO was 23.8 years, and mean age at arthroscopy was 27.0 years. Common hip arthroscopy findings included labral tears (13 hips, 81.3%), significant (≥grade 2) chondral changes (12 hips, 75%), cam impingement (7 hips, 43.8%) and pincer impingement (6 hips, 37.5%). At mean follow-up 2.8 years after arthroscopy, additional procedures had been performed in six hips (37.5%), including total hip arthroplasty in one hip. Post-PAO arthroscopy questionnaire revealed 85.7% of patients with improved hip pain, 57.1% improved hip stiffness and 57.1% improved hip function. There was no significant difference in functional outcome measures. Common post-PAO hip arthroscopy findings include labral tears, chondral changes and femoroacetabular impingement. Many patients reported subjective hip improvement from post-PAO arthroscopy, but hip outcome scores were unchanged and one-third of patients had further surgery.

  4. Does the optimal position of the acetabular fragment should be within the radiological normal range for all developmental dysplasia of the hip? A patient-specific finite element analysis.

    PubMed

    Wang, Xuyi; Peng, Jianping; Li, De; Zhang, Linlin; Wang, Hui; Jiang, Leisheng; Chen, Xiaodong

    2016-10-04

    The success of Bernese periacetabular osteotomy depends significantly on how extent the acetabular fragment can be corrected to its optimal position. This study was undertaken to investigate whether correcting the acetabular fragment into the so-called radiological "normal" range is the best choice for all developmental dysplasia of the hip with different severities of dysplasia from the biomechanical view? If not, is there any correlation between the biomechanically optimal position of the acetabular fragment and the severity of dysplasia? Four finite element models with different severities of dysplasia were developed. The virtual periacetabular osteotomy was performed with the acetabular fragment rotated anterolaterally to incremental center-edge angles; then, the contact area and pressure and von Mises stress in the cartilage were calculated at different correction angles. The optimal position of the acetabular fragment for patients 1, 2, and 3 was when the acetabular fragment rotated 17° laterally (with the lateral center-edge angle of 36° and anterior center-edge angle of 58°; both were slightly larger than the "normal" range), 25° laterally following further 5° anterior rotation (with the lateral center-edge angle of 31° and anterior center-edge angle of 51°; both were within the "normal" range), and 30° laterally following further 10° anterior rotation (with the lateral center-edge angle of 25° and anterior center-edge angle of 40°; both were less than the "normal" range), respectively. The optimal corrective position of the acetabular fragment is severity dependent rather than within the radiological "normal" range for developmental dysplasia of the hip. We prudently proposed that the optimal correction center-edge angle of mild, moderate, and severe developmental dysplasia of the hip is slightly larger than the "normal" range, within the "normal" range, and less than the lower limit of the "normal" range, respectively.

  5. Tribological assessment of a flexible carbon-fibre-reinforced poly(ether-ether-ketone) acetabular cup articulating against an alumina femoral head.

    PubMed

    Scholes, S C; Inman, I A; Unsworth, A; Jones, E

    2008-04-01

    New material combinations have been introduced as the bearing surfaces of hip prostheses in an attempt to prolong their life by overcoming the problems of failure due to wear-particle-induced osteolysis. This will hopefully reduce the need for revision surgery. The study detailed here used a hip simulator to assess the volumetric wear rates of large-diameter carbon-fibre-reinforced pitch-based poly(ether-ether-ketone) (CFR-PEEK) acetabular cups articulating against alumina femoral heads. The joints were tested for 25 x 10(6) cycles. Friction tests were also performed on these joints to determine the lubrication regime under which they operate. The average volumetric wear rate of the CFR-PEEK acetabular component of 54 mm diameter was 1.16 mm(3)/10(6) cycles, compared with 38.6 mm(3)/10(6) cycles for an ultra-high-molecular-weight polyethylene acetabular component of 28 mm diameter worn against a ceramic head. This extremely low wear rate was sustained over 25 x 10(6) cycles (the equivalent of up to approximately 25 years in vivo). The frictional studies showed that the joints worked under the mixed-boundary lubrication regime. The low wear produced by these joints showed that this novel joint couple offers low wear rates and therefore may be an alternative material choice for the reduction of osteolysis.

  6. Cementless acetabular revision: past, present, and future

    PubMed Central

    Pulido, Luis; Rachala, Sridhar R.

    2011-01-01

    Background Acetabular revision is probably the most difficult aspect of hip reconstructive surgery. Although the majority of acetabular revisions can be performed using an uncemented hemispherical acetabular device with ancillary fixation, patients with severe acetabular deficiencies and poor bone quality require more complex alternatives for revision. The limitations of traditional cementless acetabular implants has promoted the development of improved methods of fixation and revision techniques. Highly porous metals have been introduced for clinical use in arthroplasty surgery over the last decade. Their higher porosity and surface friction are ideal for acetabular revision, optimising biological fixation. The use of trabecular metal cups in acetabular revision has yielded excellent clinical results. Purpose This review focuses on the use of cementless implants for acetabular revision. The use of trabecular metal cups, augments, jumbo cups, oblong cups, cages, and structural grafting are also discussed. PMID:21234562

  7. Pre-clinical studies to validate the MITCH PCR Cup: a flexible and anatomically shaped acetabular component with novel bearing characteristics.

    PubMed

    Latif, Ahmed M H; Mehats, Aude; Elcocks, Martyn; Rushton, Neil; Field, Richard E; Jones, Eric

    2008-04-01

    A previous clinical study was undertaken to evaluate the safety and efficacy of an anatomically shaped, flexible acetabular cup. Clinical results achieved were satisfactory, although some deficiencies in the model were identified. Design changes to the original model have been implemented to improve both initial stability and long term biological fixation. This was achieved through modifications made to both the anchoring mechanism and by the application of an appropriate backing surface layer promoting bone on-growth. In addition, changes to the articulation couple have also been introduced to improve implant durability and bearing performance, utilising a carbon fibre reinforced polyetheretherketone--alumina couple. Simulated loading, in both models, was performed using Finite Element Analysis. Mechanical and tribological tests were also performed to ensure the robustness of the new optimised design. Bio-compatibility of the articulation couple was demonstrated using an animal model. Implantation of the device has been extensively tested and re-validated in vitro to achieve a favourable polar contact between cup and femoral head and establish a reproducible operative technique. This preliminary work is undertaken prior to commencing a post market surveillance study of the CE marked implant.

  8. Wear of ultra-high molecular weight polyethylene acetabular cups in a physiological hip joint simulator in the anatomical position using bovine serum as a lubricant.

    PubMed

    Bigsby, R J; Hardaker, C S; Fisher, J

    1997-01-01

    The Leeds physiological anatomical (PA) hip joint simulator was developed to apply three axes of loading and a complex three-dimensional motion so that the forces and motions can reproduce exactly the walking cycles defined by Paul. This paper presents the results of a study using the Leeds PA hip joint simulator to determine the wear of 32 mm ultra-high molecular weight polyethylene (UHMWPE) acetabular cups against stainless steel and zirconia ceramic heads, using bovine serum as lubricant. These results have been compared with the results of a previous study that used water as the lubricant, which led to UHMWPE transfer film being formed on the stainless steel head. Comparisons are also made with clinical results and results from other simulators. The study indicates that it is preferable to use bovine serum in simulator studies. In addition, the results indicate that if the surface roughness of the metallic and femoral heads are similar, and they remain undamaged during the tests, the wear rates of the UHMWPE cups are likely to be similar.

  9. The effects of irradiation and EtO-treatment on ultrahigh molecular weight polyethylene acetabular cups following accelerated aging: Degradation of mechanical properties and morphology changes during hip simulator tests

    NASA Astrophysics Data System (ADS)

    Taddei, Paola; Affatato, Saverio; Rocchi, Mirko; Fagnano, Concezio; Viceconti, Marco

    2008-03-01

    The present study was aimed at investigating the effects of the sterilization method and accelerated aging on the wear and morphology of ultrahigh molecular weight polyethylene. In a first test, gamma- and EtO-sterilized acetabular cups were tested in a hip joint simulator for two million cycles. After the test, the cups underwent an accelerated aging treatment (80 °C, 4 weeks in air furnace) and were newly tested for another three million cycles. Wear was evaluated by gravimetric measurements, morphology by micro-Raman spectroscopy. During the first test, the EtO-sterilized cups underwent a significantly higher wear than the gamma-sterilized ones (62 and 30 mg/million cycles, respectively). No significant crystallinity changes were observed. Upon accelerated aging, the crystallinity increase of the gamma-sterilized cups was more pronounced than for the EtO-sterilized cups, due to chain scission and oxygen incorporation. In the second test, the wear rate of EtO-sterilized cups decreased to 38 mg/million cycles, while for gamma-irradiated cups it increased to 84 mg/million cycles. At the same time, the latter cups underwent significant increases in temperature and crystallinity, due to the higher friction. For the EtO-sterilized cups a significant decrease in crystallinity was observed, due to the occurrence of an orthorhombic → monoclinic phase transformation.

  10. Magnetic resonance imaging evaluation of the labrum to predict acetabular development in developmental dysplasia of the hip: A STROBE compliant study.

    PubMed

    Shirai, Yasuhiro; Wakabayashi, Kenjiro; Wada, Ikuo; Tsuboi, Yoshiaki; Ha, Myongsu; Otsuka, Takanobu

    2017-05-01

    Recently, more attention has been paid to the role of the acetabular labrum. Therefore, we designed a retrospective cohort study of patients with residual hip dysplasia (RHD) who underwent magnetic resonance imaging (MRI). The objective of this study was to investigate an association between the MRI appearance of the labrum before school age and the natural history of RHD.We retrospectively investigated 45 hips of 40 patients who underwent MRI at about 3 and 4 years of age for RHD and were conservatively followed up with until 6 years of age or older. We evaluated the extent of eversion with a new method that measures the β angle (MRI β angle) using landmarks of the Graf method on MRI T2*-weighted images. The outcome measure was the Severin classification at the final follow-up. We compared the radiographic and MRI parameters at approximately 3 and 4 years of age between the good and poor outcome groups. The Student t test or one-way analysis of variance was used to compare the quantitative variables between groups. The Chi-square test was used to perform a ratio comparison.Although there was a significant difference in the center-edge (CE) angle, there was no significant difference in the acetabular index and the ratio of the presence of femoral head necrosis and the break in Shenton line between the good and poor groups. The MRI β angle was significantly greater in the poor outcome group than in the normal and good outcome groups. The cut-off value of the MRI β angle to differentiate the good and poor outcome groups was 65°, and its specificity and sensitivity were 92% and 53%, respectively.There was labral eversion on MRI scans in patients with RHD. Acetabular development before adolescence was poorer with greater labral eversion on MRI scans. The specificity for poor acetabular development was high when the MRI β angle was 65° or more. The MRI β angle has the potential to predict acetabular development.

  11. Wear and periprosthetic osteolysis in a match-paired study of modular and nonmodular uncemented acetabular cups.

    PubMed

    González Della Valle, Alejandro; Su, Edwin; Zoppi, Adriana; Sculco, Thomas P; Salvati, Eduardo A

    2004-12-01

    The wear and prevalence of periprosthetic osteolysis at 5 to 8 years of follow-up of the Trilogy cup, which has a modular liner assembled during surgery, was compared with the Implex cup, which has a fixed liner preassembled at the factory. Sixty-three patients (65 hips) with a Trilogy cup and 64 patients (65 hips) with an Implex cup were match-paired for sex, age, height, weight, and diagnosis (osteoarthritis). All patients had a cemented stem with a 28-mm head and a successful clinical and radiographic result. After an average follow-up of 5.65 years, radiographs were studied to determine the total penetration, using the Livermore technique, and the presence of osteolysis. The average total wear in the Trilogy group was 0.47 mm (range, 0-1.95 mm); for the Implex cup, it was 0.43 mm (range, 0-1.45 mm) (P.99). One patient in each group presented with periacetabular osteolysis (P.99). There was no difference in the wear rate and prevalence of periprosthetic osteolysis between the 2 groups.

  12. Management of neglected acetabular fractures.

    PubMed

    Veerappa, L A; Tripathy, S K; Sen, R K

    2015-08-01

    Management of neglected acetabular fractures is a difficult task. Osteosynthesis in such cases may not be an ideal solution because of the femoral head damage due to pressure by the fractured acetabular edge, avascular necrosis, difficulty in mobilizing the fragments due to callus formation, difficulty in indirect reduction of the fracture fragments and macerated acetabular fragments all contributing to inadequate fracture reduction. Majority of such fractures are now treated with total hip replacement. While treating such fractures with THR, problems associated with neglected acetabular fractures such as fracture non-union, hip dislocation, protrusio, cavitary bone defect or peripheral bone defect must be considered. 3D computed tomography scan provides a clear view about the acetabular and periacetabular bony anatomy. Impaction grafting and antiprotrusio cage or ring with a cemented acetabular cup can address most of the hip protrusio and cavitary bone defects. Segmental bone defect needs cortical strut-bone graft fixation and subsequent implantation of a cemented or uncemented acetabular cup implantation. Fracture non-union needs approximate reduction and fixation with plates followed by bone grafting and implantation of an acetabular cup. Despite these efforts, the outcome of THR in neglected acetabular fracture is considerable worse than after conventional hip replacement.

  13. The importance of acetabular component position in total hip arthroplasty.

    PubMed

    Daines, Brian K; Dennis, Douglas A

    2012-11-01

    Correct acetabular cup position is critical to successful total hip replacement. Unfortunately, malposition of acetabular cups is common and leads to increased rates of dislocation, wear, and ion toxicity. Despite the popularity of Lewinnek's safe zone, the exact target of acetabular abduction and version remains elusive. Differences in functional pelvic position, surgical approach, and femoral anteversion affect the optimal cup position for individual patients. Surgeons need to be aware of pelvic position changes from the supine to lateral decubitus position.

  14. Do Patients With Borderline Dysplasia Have Inferior Outcomes After Hip Arthroscopic Surgery for Femoroacetabular Impingement Compared With Patients With Normal Acetabular Coverage?

    PubMed

    Cvetanovich, Gregory L; Levy, David M; Weber, Alexander E; Kuhns, Benjamin D; Mather, Richard C; Salata, Michael J; Nho, Shane J

    2017-07-01

    The literature contains conflicting reports regarding whether outcomes of hip arthroscopic surgery for patients with borderline dysplasia are inferior to outcomes in patients with normal acetabular coverage. To assess differences in the outcomes of hip arthroscopic surgery for femoroacetabular impingement (FAI) in groups of patients with borderline dysplasia and normal coverage. Cohort study; Level of evidence, 3. A registry of consecutive patients who had undergone primary hip arthroscopic surgery with capsular plication for FAI between January 2012 and January 2014 were divided based on the preoperative lateral center-edge angle (LCEA) into 2 distinct groups: (1) borderline dysplasia (LCEA 18°-25°) and (2) normal acetabular coverage (LCEA 25.1°-40°). There were 36 patients in the borderline dysplastic group and 312 patients in the normal coverage group. The primary outcome measure was the Hip Outcome Score-Activities of Daily Living (HOS-ADL) at a minimum of 2 years postoperatively. Secondary outcome measures included the HOS-Sports and modified Harris Hip Score (mHHS). The mean preoperative LCEA differed significantly between groups (23.4° ± 1.5° for borderline dysplastic, 32.5° ± 3.8° for normal coverage; P < .001). The borderline dysplastic group had a higher percentage of female patients than the normal coverage group (27/36 [75%] vs 177/312 [57%], respectively; P = .048). There were no differences in other preoperative demographics and radiographic parameters. At a minimum 2 years after hip arthroscopic surgery (mean follow-up, 2.6 ± 0.6 years), both groups demonstrated significant improvements in all patient-reported outcome scores ( P < .001 in all cases). There were no significant differences between the borderline dysplastic and normal coverage groups in final outcome scores, score improvements, or percentage of patients experiencing clinically significant improvements. One patient in the borderline dysplastic group (3%) underwent revision hip

  15. Hip range-of-motion (ROM) is less than normal after rotational acetabular osteotomy for developmental dysplasia of the hip: A simulated ROM analysis.

    PubMed

    Hamada, Hidetoshi; Takao, Masaki; Nakahara, Ichiro; Sakai, Takashi; Nishii, Takashi; Sugano, Nobuhiko

    2016-02-01

    The optimal reorientation of the acetabulum for developmental dysplasia of the hip (DDH) is unknown in terms of hip range-of-motion (ROM). The simulated ROMs of 52 DDHs after rotational acetabular osteotomy (RAO) with several patterns of femoral head coverage and those of 73 normal hips were analyzed using computer models reconstructed from CT images. After RAO with a lateral center edge angle (LCEA) of 30° and an anterior center edge angle (ACEA) of 55° producing coverage similar to that of normal hips, the maximal flexion and maximal internal rotation at 110° flexion with 20° adduction were significantly smaller than those of the normal group. To achieve ROMs after RAO similar to those of the normal group, an LCEA of 30° with an ACEA of 45°, an LCEA of 25° with an ACEA of 45° to 50°, and an LCEA of 20° with an ACEA of 50° could be preferred angles to target, even though they provided smaller coverage than that of normal hips. After RAO producing femoral head coverage similar to that of normal hips, the maximal flexion and the maximal internal rotation at 110° flexion with 20° adduction were significantly smaller than those of the normal group.

  16. Effect of Kampo Medicine on Pain and Range of Motion of Osteoarthritis of the Hip Accompanied by Acetabular Dysplasia: Case Report and Literature Review

    PubMed Central

    Kogure, Toshiaki; Tatsumi, Takeshi; Shigeta, Tetsuya; Fujinaga, Hiroshi; Sato, Takahisa; Niizawa, Atsushi

    2011-01-01

    We report a 52-year-old female with end-stage osteoarthritis of the hip accompanied by acetabular dysplasia in whom quality of life (QOL) was improved by Kampo treatment. When she was 42 years old, she developed pain in the left hip joint, and early-stage OA of the hip was diagnosed by hip joint x-ray. Therefore, she took NSAIDs, and received conservative therapies such as diet and muscle training. However, pain in the hip joint increased and her activity of daily life (ADL) decreased at the age of 50, although she continued to receive the conservative therapies. At the age of 52, she consulted our department requesting Japanese Oriental (Kampo) Medicine. Kampo formulae; Keishikaryojutsubuto (12Tab/day: Kuracie Co. Ltd. Japan), and Boiougito (7.5 g/day: Kuracie Co. Ltd. Japan), were administered. Treatment for 3 months resulted in a decrease in the left hip joint pain using visual analogue scale (VAS) and improvement of her ADL. One year later, her joint symptoms have not increased, and both the Harris hip score and the clinical evaluation criteria of osteoarthritis of the hip have improved. The course of this disease varies depending on the lifestyle of the patient, and Kampo formulations may offer safe, potent supplemental treatment. PMID:22174570

  17. Mid-term clinical results of total hip arthroplasty using a Wagner standard cup for dysplastic hip

    PubMed Central

    Maezawa, Katsuhiko; Nozawa, Masahiko; Yuasa, Takahito; Aritomi, Kentaro; Ogawa, Seiki; Maruyama, Yuichiro; Kaneko, Kazuo

    2014-01-01

    Background The outcome of cementless total hip arthroplasty depends on many factors. We must not forget fundamental things those are design of outer surface of the component, that leads bone ingrowth into the prosthesis, better initial stability, and better insertional techniques. The purpose of this study was to review our experience with metal-on-metal total hip arthroplasty with a Wagner standard cup for patients who had acetabular dysplasia. Patients and methods Fifty-four patients with 55 hips underwent primary metal-on-metal total hip arthroplasty (Metasul prosthesis) with a Wagner standard cup (44–48 mm in outer diameter) and were followed for a minimum of 10 years. All patients received the same type of cementless femoral component (Natural hip stem) and femoral head (28 mm in diameter). Results Seventeen of the 55 Wagner standard cups (30.9%) showed aseptic loosening over a mean period of 3.6 years after surgery, and there were no bone anchors on the outer surface of the 16 retrieved cups. Conclusion From our experience, the small Wagner standard cup does not achieve sufficient osteointegration and we do not recommend the use of this cup, especially for patients with acetabular dysplasia and/or those with a small stature. PMID:25561751

  18. The Femoro-Epiphyseal Acetabular Roof (FEAR) Index: A New Measurement Associated With Instability in Borderline Hip Dysplasia?

    PubMed

    Wyatt, Michael; Weidner, Jan; Pfluger, Dominik; Beck, Martin

    2017-03-01

    The definition of osseous instability in radiographic borderline dysplastic hips is difficult. A reliable radiographic tool that aids decision-making-specifically, a tool that might be associated with instability-therefore would be very helpful for this group of patients. (1) To compare a new radiographic measurement, which we call the Femoro-Epiphyseal Acetabular Roof (FEAR) index, with the lateral center-edge angle (LCEA) and acetabular index (AI), with respect to intra- and interobserver reliability; (2) to correlate AI, neck-shaft angle, LCEA, iliocapsularis volume, femoral antetorsion, and FEAR index with the surgical treatment received in stable and unstable borderline dysplastic hips; and (3) to assess whether the FEAR index is associated clinical instability in borderline dysplastic hips. We defined and validated the FEAR index in 10 standardized radiographs of asymptomatic controls using two blinded independent observers. Interrater and intrarater coefficients were calculated, supplemented by Bland-Altman plots. We compared its reliability with LCEA and AI. We performed a case-control study using standardized radiographs of 39 surgically treated symptomatic borderline radiographically dysplastic hips and 20 age-matched controls with asymptomatic hips (a 2:1 ratio), the latter were patients attending our institution for trauma unrelated to their hips but who had standardized pelvic radiographs between January 1, 2016 and March 1, 2016. Patient demographics were assessed using univariate Wilcoxon two-sample tests. There was no difference in mean age (overall: 31.5 ± 11.8 years [95% CI, 27.7-35.4 years]; stable borderline group: mean, 32.1± 13.3 years [95% CI, 25.5-38.7 years]; unstable borderline group: mean, 31.1 ± 10.7 years [95% CI, 26.2-35.9 years]; p = 0.96) among study groups. Treatment received was either a periacetabular osteotomy (if the hip was unstable) or, for patients with femoroacetabular impingement, either an open or arthroscopic

  19. Periprosthetic acetabular fractures.

    PubMed

    Benazzo, Francesco; Formagnana, Mario; Bargagliotti, Marco; Perticarini, Loris

    2015-10-01

    The aim of this article is to propose a diagnostic and therapeutic algorithm for the acetabular periprosthetic fractures. This article explores the current literature on the epidemiology, causes and classification of periprosthetic acetabular fractures. Integrating data with the experience of the authors, it offers a guide to diagnosis and possible therapeutic strategies. Intra-operative fractures can occur during rasping, reaming or implant impaction, and they must be treated immediately if the component(s) is (are) unstable. Post-operative fractures can be due to major trauma (acute fractures) or minor forces in bone osteolysis; it is possible to plan reconstruction and fixation according to fracture characteristics. Treatment choice depends upon fracture site and implant stability. Periprosthetic acetabular fractures are uncommon complications that can occur intra-operatively or post-operatively, and a reconstructive surgeon must be able to manage the procedure. Accurate planning and reconstruction implant are necessary to achieve good cup stability.

  20. Revision of the acetabular component without cement after a previous acetabular reconstruction with use of a bulk femoral head graft in patients who had congenital dislocation or dysplasia. A follow-up note.

    PubMed

    Bal, B S; Maurer, T; Harris, W H

    1999-12-01

    Revision of an acetabular component that has failed after a total hip arthroplasty in which a bulk femoral head autogenous graft or allograft was used as a structural graft for acetabular reconstruction is an uncommon but complex and challenging procedure. We previously reported the results for seventy hips at an average of 16.5 years after a total hip arthroplasty in which an acetabular reconstruction had been performed with a femoral head graft. In the present study, we evaluated a subset of nine hips from that series that had a subsequent revision of the acetabular component without cement. The purpose of the current study was to assess the usefulness of the bone graft in this revision. The nine patients (nine hips) were followed clinically and radiographically for an average of seventy-six months (range, sixty-one to 114 months) after the index revision. In six hips the autogenous femoral head graft previously had been bolted to the lateral side of the ilium, and in one hip the femoral head allograft had been affixed in this manner. In the two remaining hips, the allograft had been placed within the acetabulum. The hips were classified according to the extent of acetabular bone loss, with use of criteria described previously. Three hips had stage-I bone loss; four, stage-II; and two, stage-IIB. A porous-coated hemispherical acetabular component was inserted without cement and fixed with screws in each hip. At least 70 percent of the porous coating was in contact with viable bone. At the time of the latest follow-up after the index revision, all nine acetabular components were functioning well without loosening or osteolysis and none had been revised. The average Harris hip score was 77 points (range, 61 to 98 points) compared with 49 points (range, 27 to 96 points) preoperatively. One hip had had revision of the femoral stem, and another had had exchange of the acetabular liner because of recurrent dislocations. There was no additional resorption of the

  1. Cementless acetabular revision arthroplasty

    PubMed Central

    Jain, Rina; Schemitsch, Emil H.; Waddell, James P.

    2000-01-01

    Objective To evaluate the effects of clinical factors on outcome after acetabular revision with a cementless beaded cup. Design Retrospective case series. Setting Tertiary care referral centre. Patients Forty-one patients who underwent acetabular revision with a cementless cup were followed up for a mean of 3.4 years. Interventions Acetabular revision with a beaded cementless cup in all patients. A morcellized allograft was used in 10 patients. Outcome measures A modified Harris hip score (range of motion measurement omitted), the SF-36 health survey, and the Western Ontario McMaster (WOMAC) osteoarthritis index. Multivariate analysis was used to evaluate the effects of age, gender, morcellized allografting, time to revision from the previous operation, acetabular screw fixation and concurrent femoral revision on outcome. Results Gender accounted for a significant portion of the variation seen in the SF-36 physical component scores (r = 0.36, p = 0.02), with women tending to have worse results. Increasing age was associated with lower WOMAC index function scores (r = 0.36, p = 0.03), whereas concurrent femoral revision tended to have a positive effect on WOMAC index function (r = 0.39, p = 0.01). None of the potential clinical predictors had any significant effect on the SF-36 mental component scores, or WOMAC index pain and stiffness scores. Conclusions In cementless acetabular revision arthroplasty, physical function, as measured by generic and limb-specific scales, may be affected by gender, age and the presence of a concurrent femoral revision. Time to revision from the previous operation, morcellized allografting and screw fixation of the acetabulum did not affect outcomes. This information may provide some prognostic value for patients’ expectations. PMID:10948687

  2. Good diagnostic performance of early migration as a predictor of late aseptic loosening of acetabular cups: results from ten years of follow-up with Roentgen stereophotogrammetric analysis (RSA).

    PubMed

    Nieuwenhuijse, Marc J; Valstar, Edward R; Kaptein, Bart L; Nelissen, Rob G H H

    2012-05-16

    Excessive early migration of femoral stems following total hip arthroplasty and tibial components following total knee arthroplasty is associated with their long-term survival and allows reliable early evaluation of implant performance. However, a similar relationship involving acetabular components following hip arthroplasty has not been evaluated. This prospective, long-term study with clinical and Roentgen stereophotogrammetric analysis (RSA) follow-up establishes the existence of this relationship and its associated diagnostic performance. Thirty-nine consecutive patients (forty-one hips) who underwent total hip arthroplasty with a cemented Exeter stem and a cemented Exeter all-polyethylene cup had prospective clinical and RSA follow-up. Patients were evaluated postoperatively at six weeks, at three, six, and twelve months, and annually thereafter. Conventional anteroposterior and lateral radiographs were made at six weeks and at two, five, and ten years postoperatively as well as when indicated. The mean duration of follow-up (and standard deviation) was 9.4 ± 3.2 years. No patients were lost to follow-up; fifteen patients died during the follow-up period. Eleven acetabular components were observed to be loose on conventional radiographs after a mean of seventy-six months (range, twelve to 140 months). During the first two postoperative years, the failed acetabular components showed markedly greater and more rapid cranial translation and sagittal rotation. Both cranial translation (hazard ratio = 19.9 [95% confidence interval, 4.94 to 80.0], p < 0.001) and sagittal rotation (hazard ratio = 11.1 [95% confidence interval, 2.83 to 43.9], p = 0.001) were strong risk factors for late aseptic loosening. Eight of the eleven failed components showed a distinctive pattern of excessive cranial translation combined with excessive sagittal rotation. The associated diagnostic performance of two-year cranial translation and/or sagittal rotation for predicting late aseptic

  3. A Novel Method for Assessment of Polyethylene Liner Wear in Radiopaque Tantalum Acetabular Cups: Clinical Validation in Patients Enrolled in a Randomized Controlled Trial.

    PubMed

    Troelsen, Anders; Greene, Meridith E; Ayers, David C; Bragdon, Charles R; Malchau, Henrik

    2015-12-01

    Conventional radiostereometric analysis (RSA) for wear is not possible in patients with tantalum cups. We propose a novel method for wear analysis in tantalum cups. Wear was assessed by gold standard RSA and the novel method in total hip arthroplasty patients enrolled in a randomized controlled trial receiving either titanium or tantalum cups (n=46). The novel method estimated the center of the head using a model based on identification of two proximal markers on the stem and knowledge of the stem/head configuration. The novel method was able to demonstrate a pattern of wear that was similar to the gold standard in titanium cups. The novel method offered accurate assessment and is a viable solution for assessment of wear in studies with tantalum cups. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Transfer of metallic debris from the metal surface of an acetabular cup to artificial femoral heads by scraping: comparison between alumina and cobalt-chrome heads.

    PubMed

    Chang, Chong Bum; Yoo, Jeong Joon; Song, Won Seok; Kim, Deug Joong; Koo, Kyung-Hoi; Kim, Hee Joong

    2008-04-01

    We aimed to investigate the transfer of metal to both ceramic (alumina) and metal (cobalt-chrome) heads that were scraped by a titanium alloy surface under different load conditions. The ceramic and metal heads for total hip arthroplasties were scraped by an acetabular metal shell under various loads using a creep tester. Microstructural changes in the scraped area were visualized with a scanning electron microscope, and chemical element changes were assessed using an energy dispersive X-ray spectrometry. Changes in the roughness of the scraped surface were evaluated by a three-dimensional surface profiling system. Metal transfer to the ceramic and metal heads began to be detectable at a 10 kg load, which could be exerted by one-handed force. The surface roughness values significantly increased with increasing test loads in both heads. When the contact force increased, scratching of the head surface occurred in addition to the transfer of metal. The results documented that metallic debris was transferred from the titanium alloy acetabular shell to both ceramic and metal heads by minor scraping. This study suggests that the greatest possible effort should be made to protect femoral heads, regardless of material, from contact with metallic surfaces during total hip arthroplasty.

  5. Evaluation of the hip center in total hip arthroplasty for old developmental dysplasia.

    PubMed

    Flecher, Xavier; Parratte, Sebastien; Brassart, Nicolas; Aubaniac, Jean-Manuel; Argenson, Jean-Noël

    2008-12-01

    We describe the problems with positioning the hip center according to the severity of dislocation in 97 cementless total hip arthroplasty for developmental dysplasia of the hip. The mean location of the hip center from the interteardrop was 30.4 +/- 8.7 mm horizontally and 23.4 +/- 5.4 mm vertically. The presence of a limp correlated with a superior placement of the cup. Four cups were revised, 2 of which with a significant high hip center. The survival rate of the acetabular component was 95% at 12 years. Craniopodal repositioning was easy in class 1. In class 2, the cup was the largest. In class 3, the greatest variations of the hip center were found. In class 4, the smallest implants were necessary for positioning in the true acetabulum.

  6. Importance of maintaining the basic stress pathway above the acetabular dome during acetabular reconstruction.

    PubMed

    Nie, Yong; Pei, Fuxing; Shen, Bin; Kang, Pengde; Li, Zongming

    2016-01-01

    The basic stress pathway above the acetabular dome is important for the maintenance of implant stability in press-fit acetabular reconstruction of total hip arthroplasty. However, information on the basic stress pathway and its impact factors remains unclear. The objective of this study was to investigate the effects of the orientations and positions of the acetabular component on the basic stress pathway. The basic stress pathway above the acetabular dome was defined as two parts: 3D basic trabecular bone stress distribution and quantified basic cortical bone stress level, using two subject-specific finite element normal hip models. The effects were then analysed by generating 32 reconstructed acetabular cases with different cup abduction and anteversion angles within a range of 35-50° and 10-25°, respectively, and 12 cases with different hip centre heights within a range of 0-15 mm above the acetabular dome. The 3D trabecular stress distribution decreased remarkably in all cases, while the 80% of the basic cortical bone stress level was maintained in cases when the acetabular component was positioned at 10° or 15° anteversion and 40° or 45° abduction angles. The basic stress pathway above the acetabular dome was disturbed when the superior displacement of the hip centre exceeded 5 mm above the anatomical hip centre. Positioning the acetabular component correctly contributes to maintain the stress balance between the acetabular cup and the bone during acetabular reconstruction, thus helping restore the normal hip biomechanics and preserve the stability of the implants.

  7. [Periprosthetic acetabular fractures in geriatric patients].

    PubMed

    Herath, S C; Rollmann, M F R; Histing, T; Holstein, J H; Pohlemann, T

    2017-02-01

    Periprosthetic acetabular fractures in geriatric patients are rare injuries; however, the incidence is increasing because of the current demographic developments. For diagnosis of periprosthetic acetabular fractures, conventional X‑ray images are regularly complemented by computed tomography (CT). For exclusion of loosening of the prosthesis more advanced techniques, such as single photon emission CT (SPECT/CT) are applied. In addition to classification of periprosthetic acetabular fractures by the traditional system of Letournel there are several other classification systems, which take into account the etiology of the fracture and the stability of the prosthesis. While, under certain circumstances conservative treatment of periprosthetic acetabular fractures is possible, operative treatment often requires extensive surgical procedures to restore the stability of the acetabulum as a support for the cup of the prosthesis. Besides the traditional techniques of acetabular osteosynthesis, special revision systems, augmentations and allografts are used for the reconstruction of periprosthetic acetabular fractures. To determine a therapeutic regimen patient-specific preconditions as well as fracture pattern and type of prosthesis need to be taken into account. In the literature there are several algorithms, which are aimed at supporting the attending physician in making the correct decision for the treatment of periprosthetic acetabular fractures. In cases of periprosthetic acetabular fractures even experienced surgeons are faced with great challenges. Thus, treatment should be carried out in specialized centers.

  8. Porous tantalum uncemented acetabular shells in revision total hip replacement: two to four year clinical and radiographic results.

    PubMed

    Kim, W Y; Greidanus, N V; Duncan, C P; Masri, B A; Garbuz, D S

    2008-01-01

    In cementless revision total hip arthroplasty (THA), achieving initial implant stability and maximising host bone contact is key to the success of reconstruction. Porous tantalum acetabular shells may represent an improvement from conventional porous coated uncemented cups in revision acetabular reconstruction associated with severe acetabular bone defects. We reviewed the results of 46 acetabular revisions with Paprosky 2 and 3 acetabular bone defects done with a hemispheric, tantalum acetabular shell and multiple supplementary screws. At a mean follow-up of 40 (24-51) months, one acetabular shell had been revised in a patient with a Paprosky 3B defect. Cementless acetabular revision with the tantalum acetabular shell demonstrated excellent early clinical and radiographic results and warrants further evaluation in revision acetabular reconstruction associated with severe acetabular bone defects.

  9. Optimization of acetabular component orientation using DOE

    NASA Astrophysics Data System (ADS)

    Krepelka, Mircea; Toth-Taşcǎu, Mirela

    2012-09-01

    Stress shielding is increasingly recognized as an important cause of acetabular component failure. Several studies have been focused on improving the acetabular component placement to reduce the risk of dislocation, impingement and range of motion but little is known of its influence on implant-bone interface pressures. This study employs experimental design, 3D reconstruction and FE simulation to identify the most significant factors for acetabular component behavior and predict the best configuration of acetabular spatial orientation angles within the constraints of the Lewinnek's safe zone in order to minimize peak contact pressures. Data analysis by response surface method revealed that the magnitude of periacetabular pressures was significantly reduced by the anteversion angle at its lowest value as well as the abduction angle located at the central point value, which corresponded to a 40° abduction and 5° anteversion of cup orientation.

  10. Acetabular augmentation induced by extracorporeal shock waves in rabbits.

    PubMed

    Saisu, Takashi; Kamegaya, Makoto; Wada, Yuichi; Takahashi, Kenji; Mitsuhashi, Shigeru; Moriya, Hideshige; Maier, Markus

    2005-05-01

    We conducted this animal study to demonstrate whether exposing the acetabulum in immature rabbits to extracorporeal shock waves induces bone formation in the acetabulum. Five thousand shock waves of 100 MPa each were directed, from outside, at the acetabular roof of eight immature rabbits. At each of two time points (4 and 8 weeks) after treatment, the pelvises of four rabbits were removed and evaluated morphologically. Woven bone formation was observed on the lateral margin of the acetabular roof at 4 weeks after treatment, and the breadth of the acetabular roof in the coronal plane was significantly increased. Eight weeks after treatment, the woven bone disappeared; the breadth of the acetabular roof, however, was significantly increased. These findings demonstrated that extracorporeal shock waves induced acetabular augmentation in rabbits. We conclude that extracorporeal shock waves, perhaps, could be applied clinically for the treatment of acetabular dysplasia.

  11. Total Hip Arthroplasty Using Modular Trabecular Metal Acetabular Components for Failed Treatment of Acetabular Fractures: A Mid-term Follow-up Study

    PubMed Central

    Huang, De-Yong; Zhang, Liang; Zhou, Yi-Xin; Zhang, Chun-Yu; Xu, Hui; Huang, Yong

    2016-01-01

    Background: Porous-coated cups have been widely used in acetabular reconstruction after failed treatment of acetabular fractures, and good results have been reported with the use of these cups; however, the durability and functionality of modular trabecular metal (TM) acetabular components in acetabular reconstruction after failed treatment of acetabular fractures remain unclear. This study aimed to examine the radiographic and clinical outcomes associated with the use of modular TM acetabular components for failed treatment of acetabular fractures to assess the durability and functionality of these components in acetabular reconstruction after failed treatment of acetabular fractures. Methods: A total of 41 patients (41 hips) underwent total hip arthroplasty (THA) using modular TM acetabular components for failed treatment of acetabular fractures at our hospital between January 2007 and December 2012. Among these patients, two were lost to follow-up. Therefore, 39 patients (39 hips) were finally included in this study. The Harris hip score before and after the surgery, satisfaction level of the patients, and radiographic results were assessed. Results: The mean Harris hip score increased from 34 (range, 8–52) before surgery to 91 (range, 22–100) at the latest follow-up examination (P < 0.001). The results were excellent for 28 hips, good for six, fair for three, and poor for two. Among the 39 patients, 25 (64%) and 10 (26%) were very satisfied and somewhat satisfied, respectively. All cups were found to be fully incorporated, and no evidence of cup migration or periacetabular osteolysis was noted. Conclusions: Despite the technically demanding nature of the procedure, THA using modular TM acetabular components showed good durability and functionality and may be an effective reconstruction option for failed treatment of acetabular fractures. PMID:27064033

  12. Surgical treatment of developmental dysplasia of the hip in adults: II. Arthroplasty options.

    PubMed

    Sanchez-Sotelo, Joaquin; Berry, Daniel J; Trousdale, Robert T; Cabanela, Miguel E

    2002-01-01

    Total hip arthroplasty is the procedure of choice for most patients with symptomatic end-stage coxarthrosis secondary to hip dysplasia. The anatomic abnormalities associated with the dysplastic hip increase the complexity of hip arthroplasty. When pelvic bone stock allows, it is desirable to reconstruct the socket at or near the normal anatomic acetabular location. To obtain sufficient bony coverage of the acetabular component, the socket can be medialized or elevated, or a lateral bone graft can be applied. Uncemented acetabular components allow biologic fixation with potentially improved results compared with cemented cups, especially in young patients. The location of the acetabular reconstruction and the desired leg length influence the type of femoral reconstruction. Cemented and uncemented implants can be used in femoral reconstruction, depending on the clinical situation. Femoral shortening is required in some cases and can be performed by metaphyseal resection with a greater trochanteric osteotomy and advancement or by a shortening subtrochanteric osteotomy. The results of total hip arthroplasty demonstrate a high rate of pain relief and functional improvement. The long-term durability of cemented total hip arthroplasty reconstruction in these patients is inferior to that in the general population. The results of uncemented implants are promising, but only limited early and midterm data are available.

  13. Current concept in dysplastic hip arthroplasty: Techniques for acetabular and femoral reconstruction

    PubMed Central

    Bicanic, Goran; Barbaric, Katarina; Bohacek, Ivan; Aljinovic, Ana; Delimar, Domagoj

    2014-01-01

    Adult patients with developmental dysplasia of the hip develop secondary osteoarthritis and eventually end up with total hip arthroplasty (THA) at younger age. Because of altered anatomy of dysplastic hips, THA in these patients represents technically demanding procedure. Distorted anatomy of the acetabulum and proximal femur together with conjoined leg length discrepancy present major challenges during performing THA in patients with developmental dysplasia of the hip. In addition, most patients are at younger age, therefore, soft tissue balance is of great importance (especially the need to preserve the continuity of abductors) to maximise postoperative functional result. In this paper we present a variety of surgical techniques available for THA in dysplastic hips, their advantages and disadvantages. For acetabular reconstruction following techniques are described: Standard metal augments (prefabricated), Custom made acetabular augments (3D printing), Roof reconstruction with vascularized fibula, Roof reconstruction with pedicled iliac graft, Roof reconstruction with autologous bone graft, Roof reconstruction with homologous bone graft, Roof reconstruction with auto/homologous spongious bone, Reinforcement ring with the hook in combination with autologous graft augmentation, Cranial positioning of the acetabulum, Medial protrusion technique (cotyloplasty) with chisel, Medial protrusion technique (cotyloplasty) with reaming, Cotyloplasty without spongioplasty. For femoral reconstruction following techniques were described: Distraction with external fixator, Femoral shortening through a modified lateral approach, Transtrochanteric osteotomies, Paavilainen osteotomy, Lesser trochanter osteotomy, Double-chevron osteotomy, Subtrochanteric osteotomies, Diaphyseal osteotomies, Distal femoral osteotomies. At the end we present author’s treatment method of choice: for acetabulum we perform cotyloplasty leaving only paper-thin medial wall, which we break during

  14. Treatment algorithm of acetabular periprosthetic fractures.

    PubMed

    Simon, Paul; von Roth, Philipp; Perka, Carsten

    2015-10-01

    Periprosthetic fractures of the acetabulum represent a rare incident in primary and revision total hip arthroplasty. The management of these fractures can be challenging. At present, there are no reliable guidelines for the treatment of periprosthetic acetabular fractures. Periprosthetic acetabular fractures can occur intra-operatively, in particular during insertion of non-cemented cups or in the context of revision surgery. Post-operative causes for periprosthetic acetabular fractures are traumatic events or, more commonly, pelvic discontinuity due to severe bone loss related to osteolysis. Despite their aetiology, the main objective of surgery is to achieve a stable acetabular component and fracture. While stable fractures and implants could be treated non-operatively, unstable fractures require surgery to achieve component stability and allow appropriate biological fixation of the revision cup. Assessment of the stability plays a crucial role before determining the treatment strategy. There is a large variety of surgical techniques available for the management of these fractures. This review article outlines the epidemiology, aetiology and current classification systems, and provides a distinct diagnostic and therapeutic algorithm for the treatment of periprosthetic acetabular fractures.

  15. Fixation strength analysis of cup to bone material using finite element simulation

    NASA Astrophysics Data System (ADS)

    Anwar, Iwan Budiwan; Saputra, Eko; Ismail, Rifky; Jamari, J.; van der Heide, Emile

    2016-04-01

    Fixation of acetabular cup to bone material is an important initial stability for artificial hip joint. In general, the fixation in cement less-type acetabular cup uses press-fit and screw methods. These methods can be applied alone or together. Based on literature survey, the additional screw inside of cup is effective; however, it has little effect in whole fixation. Therefore, an acetabular cup with good fixation, easy manufacture and easy installation is required. This paper is aiming at evaluating and proposing a new cup fixation design. To prove the strength of the present cup fixation design, the finite element simulation of three dimensional cup with new fixation design was performed. The present cup design was examined with twist axial and radial rotation. Results showed that the proposed cup design was better than the general version.

  16. Acetabular component deformation with press-fit fixation.

    PubMed

    Squire, Matthew; Griffin, William L; Mason, J Bohannon; Peindl, Richard D; Odum, Susan

    2006-09-01

    Acetabular component deformation secondary to forces encountered during insertion is a potential consequence of the press-fit technique. This study characterized the stiffness of Pinnacle 100 cups (DePuy, Warsaw, Ind) via mechanical testing and used this information with intraoperative measurements of cup deformation to calculate the in vivo forces acting on cups inserted during hip arthroplasty in 21 patients. We found that 90.5% of cups had measurable compression deformity, averaging 0.16 +/- 0.16 mm. The corresponding forces acting on these cups averaged 414 +/- 421 N. For hard-on-hard bearing surfaces, such in vivo deformation of acetabular shells may result in negative clinical consequences such as equatorial loading with increased wear and potential seizing of components, chipping of ceramic inserts, or locking mechanism damage.

  17. Finite element modelling for assessing effect of acetabular component orientation on the basic stress path above acetabular dome.

    PubMed

    Nie, Yong; Pei, Fu-xing; Li, Zong-ming

    2015-02-01

    To investigate the effect of acetabular component orientation on the basic stress path above the acetabular dome in the recommended safe zone. A subject-specific normal hip finite element model was generated and a convergence study carried out to determine the number of material properties for trabecular bone using a normal hip model. Four abduction angles (35°, 40°, 45° and 50°) and four anteversion angles (10°, 15°, 20° and 25°) from the recommended safe zone of acetabular cup orientation were chosen to simulate acetabular reconstruction. The distribution and level of periacetabular stress was assessed using a normal hip model as a control and 16 reconstructed acetabula in simulated single-legged stances. The error of the average stress between plans four and five (50 and 100 materials for trabecular bone respectively) was 4.8%, which is less than the previously defined 5% error. The effect of acetabular component orientation on stress distribution in trabecular bone was not pronounced. When the acetabular component was at 15° anteversion and the abduction angle was 40° or 45°, the stress level on posterolateral cortical bone above the acetabular dome was as stable as that in the normal hip model. Acetabular component orientation affects the basic stress path above the acetabular dome. Thus, orientation should be considered when attempting to restore normal biomechanics in the main load-bearing area. © 2015 Chinese Orthopaedic Association and Wiley Publishing Asia Pty Ltd.

  18. [Hip dysplasia in adolescence].

    PubMed

    Barthès, X; Seringe, R

    1995-01-01

    Hip growth continues on till adolescence with the fusion of the different ossification centers. Does this growth exist in hip dysplasia? What is the role of surgery at adolescence? Is an additional varus osteotomy indicated with a pelvic osteotomy? Clinical and radiological criteria of adolescent hip dysplasia were studied in a series of 18 patients (mean age 12 years). The 28 hips were divided into 4 groups depending on the treatment: non operated hips (group 1, N = 8), hips operated on only by pelvic osteotomy (group 2, N = 8), hips operated on by combined pelvic and femoral osteotomies (group 3, N = 9), and hips operated on only by femoral osteotomy (group 4, N = 3). Tonnis's clinical criteria were used. The acetabular index of the weight bearing zone, the center-edge angle of Wiberg, the acetabular angle of Idelberger and Frank, the neck-shaft angle, the head coverage index were measured and compared between the 4 groups (average follow-up was 46 months). We noted continuation of growth of the acetabulum at adolescence with a correction of moderate hip dysplasia when the head was covered (group 1), the acetabular index of the weight-bearing zone decreased from 20.1 degrees to 11.1 degrees; the center-edge angle of Wiberg increased from 15.25 degrees to 23 degrees. The comparison of groups 2 and 3 showed that an additional femoral osteotomy does not change significantly the radiologic results. Does surgery benefit at adolescence from the growth which exists during this period? The clinical results and the evolution of arthrosis following a Chiari pelvic osteotomy are better when the operation is performed early. A pelvic osteotomy is indicated in symptomatic hips, when the congruity is abnormal, with deficient head coverage, as well as moderate dysplasia when the evolution of the acetabular parameters are not satisfactory. A femoral osteotomy in addition to a pelvic osteotomy does not seem justified.

  19. Kidney Dysplasia

    MedlinePlus

    ... Disease Ectopic Kidney Medullary Sponge Kidney Kidney Dysplasia Kidney Dysplasia What is kidney dysplasia? Kidney dysplasia is a condition in which ... Kidney dysplasia in one kidney What are the kidneys and what do they do? The kidneys are ...

  20. Satisfying Results of Primary Hip Arthroplasty in Patients With Hip Dysplasia at a Mean Followup of 20 Years.

    PubMed

    Colo, Ena; Rijnen, Wim H C; Gardeniers, Jean W M; van Kampen, Albert; Schreurs, B Willem

    2016-11-01

    Developmental dysplasia of the hip (DDH) is a common cause of secondary osteoarthritis (OA) in younger patients, and when end-stage OA develops, a THA can provide a solution. Different options have been developed to reconstruct these defects, one of which is impaction bone grafting combined with a cemented cup. To determine the true value of a specific technique, it is important to evaluate patients at a long-term followup. As there are no long-term studies, to our knowledge, on THA in patients with DDH using impaction bone grafting with a cemented cup, we present the results of this technique at a mean of 15 years in patients with previous DDH. We wished to determine (1) the long-term probability of cup revision at a minimum followup of 15 years for cemented acetabular impaction bone grafting in patients with DDH; (2) the radiographic appearance of the bone graft and radiographic signs of implant loosening; and (3) the complications and pre- and postoperative Harris hip scores with cemented THA combined with impaction bone grafting in patients with previous DDH. Between January 1984 and December 1995 we performed 28 acetabular impaction bone grafting procedures for secondary OA believed to be caused by DDH in 22 patients; four patients died before 15 years, leaving 24 hips in 18 patients for retrospective analysis at a minimum of 15 years (mean, 20 years; range, 16-29 years). The diagnosis of DDH was made according to preoperative radiographs and intraoperative findings. All grades of dysplasia were included; five patients had Crowe Group I, eight had Group II, nine had Group III, and two had Group IV DDH. No patients were lost to followup. In all cases the acetabular defects were combined cavitary and segmental. Owing to the high number of deaths, we performed a competing-risk analysis to determine the probability of cup revision surgery. The competing-risk analysis showed cumulative incidences at 15 and 20 years, with endpoint revision for any reason of 7% (95

  1. Comparative survival analysis of porous tantalum and porous titanium acetabular components in total hip arthroplasty.

    PubMed

    Vutescu, Emil S; Hsiue, Peter; Paprosky, Wayne; Nandi, Sumon

    2017-02-04

    Porous tantalum acetabular components (PoTa) are well-studied, but less is known about widely used porous titanium (PoTi) acetabular components. We performed a comparative survival analysis between PoTi and PoTa acetabular components. Primary or revision THA performed using PoTi (n = 2,976) or PoTa (n = 184) acetabular components with minimum 2-year follow-up (PoTi n = 1,539; PoTa n = 157) were analysed. Univariate and multivariate logistic regression were performed to test the effect of porous metal acetabular component type on revision surgery for aseptic cup loosening. Multivariate model was adjusted for acetabular defect severity according to the Paprosky Classification. Only PoTi components used in revision THA failed. Survival of the PoTi acetabular component was 98.6% when used in revision THA at mean 48.3-month follow-up. After adjusting for severity of acetabular defect, there was no difference in survival between PoTi and PoTa acetabular components when used in primary or revision THA. After adjusting for acetabular defect severity, both PoTa and PoTi acetabular components had excellent survival at mean 44.4-month (range 4.3-91.5 months) follow-up when used in primary and revision THA.

  2. [Osteosynthesis and cup revision in periprosthetic acetabulum fractures using a Kocher-Langenbeck approach].

    PubMed

    Schwabe, P; Märdian, S; Perka, C; Schaser, K-D

    2016-04-01

    Reconstruction/stable fixation of the acetabular columns to create an adequate periacetabular requirement for the implantation of a revision cup. Displaced/nondisplaced fractures with involvement of the posterior column. Resulting instability of the cup in an adequate bone stock situation. Periprosthetic acetabulum fractures with inadequate bone stock. Extended periacetabular defects with loss of anchorage options. Isolated periprosthetic fractures of the anterior column. Septic loosening. Dorsal approach. Dislocation of hip. Mechanical testing of inlaying acetabular cup. With unstable cup situation explantation of the cup, fracture fixation of acetabulum with dorsal double plate osteosynthesis along the posterior column. Cup revision. Hip joint reposition. Early mobilization; partial weight bearing for 12 weeks. Thrombosis prophylaxis. Clinical and radiological follow-ups. Periprosthetic acetabular fracture in 17 patients with 9 fractures after primary total hip replacement (THR), 8 after revision THR. Fractures: 12 due to trauma, 5 spontaneously; 7 anterior column fractures, 5 transverse fractures, 4 posterior column fractures, 1 two column fracture after hemiendoprosthesis. 5 type 1 fractures and 12 type 2 fractures. Operatively treated cases (10/17) received 3 reinforcement ring, 2 pedestal cup, 1 standard revision cup, cup-1 cage construct, 1 ventral plate osteosynthesis, 1 dorsal plate osteosynthesis, and 1 dorsal plate osteosynthesis plus cup revision (10-month Harris Hip Score 78 points). Radiological follow-up for 10 patients: consolidation of fractures without dislocation and a fixed acetabular cup. No revision surgeries during follow-up; 2 hip dislocations, 1 transient sciatic nerve palsy.

  3. Long-Term Clinical and Radiographic Outcomes of Porous Tantalum Monoblock Acetabular Component in Primary Hip Arthroplasty: A Minimum of 15-Year Follow-Up.

    PubMed

    De Martino, Ivan; De Santis, Vincenzo; Sculco, Peter K; D'Apolito, Rocco; Poultsides, Lazaros A; Gasparini, Giorgio

    2016-09-01

    The porous tantalum monoblock cup has demonstrated excellent short-term and midterm clinical and radiographic outcomes in primary THA, but longer follow-up is necessary to confirm the durability of these results into the second decade. The purpose of this study is to report the clinical and radiographic outcomes for this monoblock cup with a minimum 15-year follow-up. From June 1998 to December 1999, 61 consecutive patients (63 hips) underwent primary THA with a tantalum monoblock acetabular component. All patients were followed clinically and radiographically for a minimum of 15 years. At a mean of 15.6 years (range, 15-16 years) of follow-up, 5 patients had died, and 4 had been lost to follow-up, leaving 52 patients (54 hips) for analysis. The underlying diagnosis that led to the primary THA was primary osteoarthritis in 43 hips, avascular necrosis in 4, developmental hip dysplasia in 3, rheumatoid arthritis in 3 and post-traumatic osteoarthritis in 1. One cup was revised for deep infection; at surgery, the cup showed osseointegration. At a mean follow-up of 15.6 years (range, 15-16 years), the survivorship with cup revision for aseptic loosening as end point was 100%. There was no radiographic evidence of loosening, migration, or gross polyethylene wear at last follow-up. The mean Harris Hip Scores improved from 47 points preoperatively to 94 points. The porous tantalum monoblock cup in primary THA demonstrated excellent clinical and radiographic outcomes with no failures because of osteolysis or loosening at a minimum follow-up of 15 years. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. [Acetabular morphological analysis in patients with high dislocated DDH using three-dimensional surface reconstruction technique].

    PubMed

    Zengy, Yi; Min, Li; Lai, Ou-jie; Shen, Bin; Yang, Jing; Zhou, Zong-ke; Kang, Peng-de; Pei, Fu-xing

    2015-03-01

    To simulate acetabular morphology and perform acetabular quantitative analysis in high dislocated developmental dysplasia of the hip (DDH) patients using three-dimensional (3D) surface reconstruction technique, in order to understand the acetabular anatomic features and develop operative strategies for acetabular reconstruction. 3D pelvic images were reconstructed by Mimics software from CT data of 13 patients (13 hips) with high developmental DDH and 13 normal persons (26 hips). True acetabular superior-inferior diameter, anterior-posterior diameter, acetabular depth, medial wall thickness, abduction angle and anteversion angle were measured and compared between the two groups of participants. Irregular acetabular shape was found in high dislocated group, showing a triangle with wide upper and narrow lower. The acetabular quantitative analysis revealed (38.29 +/- 2.71) mm superior-inferior diameter, (21.74 +/- 5.33) mm anterior-posterior diameter, (15.50 +/- 2.93) mm acetabular depth, (6.80 +/- 2.97) mm medial wall thickness, (49.29 +/- 7.40) degrees abduction angle and (23.82 +/- 11.21) degrees anteversion angle in high dislocated patients. The superior-inferior diameter, anterior-posterior diameter and acetabular depth of high dislocated patients were significantly smaller than those of the normal contirols (P<0.05). However, the medial wall thickness, abduction angle and anteversion angle of high dislocated patients were significantly bigger than those of the normal controls (P<0.05). 3D reconstruction technique can restore true acetabular morphology and perform quantitative analysis. Compared with normal controls, high dislocated DDH patients have acetabular features: irregular shape, lower opening, higher medial wall and bigger abduction and anteversion angles. Joint arthroplasty surgery in high dislocated DDH patients needs to look at these acetabular features.

  5. The Exeter method-acetabular impaction grafting with cemented reimplantation.

    PubMed

    Petheram, T G; Howell, J R

    2014-04-01

    Restoration of acetabular anatomy and biomechanics at revision hip surgery by replacing deficient acetabular bone through impaction of allograft and/or autograft bone chips. Aseptic loosening of the socket due to osteolysis, bone loss from infection, iatrogenic bone loss due to implant removal, and in the primary setting protrusio acetabuli, dysplasia and previous acetabular fracture. Large segmental peripheral acetabular defects which cannot be contained, the presence of untreated infection, unstable acetabular fractures, previous radiotherapy to the affected hip area. Sound exposure of the acetabulum with delineation of the bony defect. Creation of a host environment suitable for bone graft and containment of segmental defects using rim mesh or porous augments. Impaction grafting using layered allograft or autograft bone chips of 0.8-1 cm(3), packed using hemispherical impactors, followed by cementing of a polyethylene acetabular component with pressurisation. Partial weight bearing 6 weeks, modified depending on level of containment and intra-operative findings. A successful and reproducible technique with survival up to 87 % at 20 years for aseptic loosening in the revision setting.

  6. Total arthroplasty in displaced dysplastic hips with acetabular reconstruction and femoral shortening - technical note.

    PubMed

    Silva, Paulo; de Oliveira, Leandro Alves; Coelho, Danilo Lopes; do Amaral, Rogério Andrade; Rebello, Percival Rosa; de Moraes, Frederico Barra

    2014-01-01

    To describe a new procedure of total hip replacement in patient with severe developmental dysplasia of the left hip, using technique of acetabular reconstruction with autogenous bone grafts and subtrochanteric shortening femoral osteotomy. Total hip replacement done in January of 2003. The Eftekhar's classification was used and included type D, neglected dislocations. Bone graft incorporated in acetabular shelf and femoral osteotomy. Our contribution is the use of an Allis plate to better fix acetabular grafts, avoiding loosening, and cerclage around bone graft in femoral osteotomy site, which diminish pseudoarthrosis risk. This technique shows efficiency, allowing immediately resolution for this case with pain and range of motion of hip improvement. It also allows the acetabular dysplasia reconstruction, equalization of the limb length (without elevated risk of neurovascular lesion) and repairs the normal hip biomechanics due to the correction of the hip's center of rotation.

  7. New method for measuring acetabular component positioning with EOS imaging: feasibility study on dry bone.

    PubMed

    Journé, Alexandre; Sadaka, Jérome; Bélicourt, Claire; Sautet, Alain

    2012-11-01

    Malposition of the acetabular cup is the most common cause of total hip arthroplasty (THA) dislocation. The position of a total hip implant is usually analysed on computed tomography (CT) scan. We aim to prove it is possible to measure, with good accuracy, the position of an acetabular cup using the low-dose irradiation (EOS) imaging. We implanted an acetabular cup in a pelvic dry bone and measured cup anteversion and inclination with scanography. We performed 14 series of EOS acquisitions with different inclination, rotation and pelvic tilt, which were analysed by five observers. Two observers repeated angle measurements. We then calculated measurement inter- and intrareproducibility and accuracy. Using a confidence interval (CI) of 95 %, inter- and intra-observer reproducibility were ±1.6, and ±1.4°, respectively, for cup inclination; accuracy in comparison with CT was ±2.6°. Using a 95 % CI, inter- and intra-observer reproducibility for cup anteversion were ±2.5° and ±2.3°, respectively. Measurement accuracy compared with CT was ±3.9°. EOS imaging system is superior to standard radiography in terms of measuring acetabular anteversion and inclination.

  8. A technique to remove a stable all-polyethylene cemented acetabular liner in revision hip arthroplasty: A case report

    PubMed Central

    Judas, Fernando M.; Lucas, Francisco M.; Fonseca, Ruben L.

    2015-01-01

    Introduction The removal of a well-fixed acetabular component in a total hip arthroplasty can cause bone fractures, excessive bleeding, as well as extended bone loss. The reimplantation of a new acetabular component may be compromised. Presentation of case We report a technique using 2 cork-screws for removal a stable cemented acetabular component for the treatment of a recurrent dislocation of a cemented total hip arthroplasty, due to acetabular malposition. Discussion A diversity of approaches and tools has been used for extraction of the acetabular prosthesis. Using 2 cork-screws it is possible to create fissures and fractures into the cement mantle, and greater manual control is obtained facilitating the manipulation of the acetabular component in different directions. The cup-cemented bond can be disrupted, the host bone is preserved and the risks of complications are minimized. Conclusion This technique is simple, available in any environment, reproducible, non-costly, non-timing consuming and safe. PMID:25725330

  9. [Total hip arthroplasty for treatment of Crowe type IV congenital dysplasia of hip with dislocation in adults].

    PubMed

    Li, Wenbo; Zhang, Wenming; Bai, Guochang; Huang, Zida; Shen, Rongkai

    2013-10-01

    To study the effectiveness and acetabular prosthesis selection of the total hip arthroplasty (THA) for Crowe type IV congenital dysplasia of the hip with dislocation in adults. Between June 2008 and May 2012, 8 adult patients (8 hips) with Crowe type IV congenital dysplasia of the hip with dislocation underwent THA. They were all female, aged 20-35 years with a mean age of 25 years. The left hip was involved in 5 cases and the right hip in 3 cases. The Harris score of involved hip was 53.9 +/- 6.6. The shortened length of involved extremity was 4-6 cm (mean, 4.8 cm). The X-ray films showed complete dislocation in all cases. The acetabular prosthesis with diameter of 42-44 mm and S-ROM femoral prosthesis were used in THA. The incisions healed by first intention. There was no hip dislocation events and sciatic nerve injury during the follow-up. Femoral nerve injury occurred in 1 case and asymptomatic venous thrombosis of the leg muscle occurred in 2 cases. All the patients were followed up 1-5 years (mean, 3 years). All cases showed obvious improvement of claudication and could restore to work. At 6 months after operation, the mean length difference between affected and contralateral extremities was 0.4 cm (range, 1.0-0.6 cm); the Harris score was significantly increased to 87.6 +/- 0.3 (t = 1.77, P = 0.00). The X-ray films showed that all cases got bony union at 3-6 months after operation and stable interface between acetabular prosthesis and bone. No revision was involved during the follow-up. THA with small acetabular cup and subtrochanteric osteotomy is an effective method in the treatment of Crowe type IV congenital dysplasia of the hip with dislocation in adults. The early effectiveness is satisfactory. The long-term survival rate of prosthesis needs to be followed up.

  10. Initial Results of an Acetabular Center Axis Registration Technique in Navigated Hip Arthroplasty with Deformed Acetabular Rims

    PubMed Central

    Wada, Hiroshi; Mishima, Hajime; Yoshizawa, Tomohiro; Sugaya, Hisashi; Nishino, Tomofumi; Yamazaki, Masashi

    2016-01-01

    Background In cementless total hip arthroplasty, imageless computer-assisted navigation is usually used to register the anterior pelvic plane (APP). The accuracy of this method is influenced by the subcutaneous tissues overlying the registration landmarks. On the other hand, the acetabular center axis (ACA) is determined from the acetabular rim. Precise registration of the ACA is possible because of direct palpation using a pointer. Imageless navigation using the ACA usually targets patients with normal acetabular morphology. The aim of this study was to investigate the accuracy of imageless navigation using the ACA instead of the APP in patients with normal or deformed acetabular rims. Methods The intraoperative cup position was compared with that obtained from the postoperative computed tomography (CT) images in 18 cases. Results The inclination angle derived from the navigation system was 3.4 ± 5.3 degrees smaller and the anteversion angle was 1.4 ± 3.1 degrees larger than those derived from the CT images. Conclusion The inclination cup angle of the navigation system was significantly inferior to the true value, particularly in cases with large anterior osteophytes. PMID:27073586

  11. A computer simulation of rotational acetabular osteotomy for dysplastic hip joint: does the optimal transposition of the acetabular fragment exist?

    PubMed

    Tsumura, Hiroshi; Kaku, Nobuhiro; Ikeda, Shinichi; Torisu, Takehiko

    2005-01-01

    For young patients who have early signs of coxarthrosis resulting from acetabular dysplasia, periacetabular osteotomies for correcting abnormal stress distribution can be useful for preventing the progression of the disease. However, it is difficult to confirm the optimal transposition of the osteotomized acetabular fragment. To deal with this problem, we devised a computer program to support preoperative planning. Hip images obtained by computed tomography were loaded into our program, and a three-dimensional voxel model was created. Then, osteotomy was simulated and the pressure distribution was analyzed with a rigid-body spring analysis (computational nonlinear mechanical analysis). The three-dimensional pressure distributions in seven dysplastic hips were evaluated before and after virtual rotational acetabular osteotomy. A peak pressure was calculated for every 5 degrees of rotation of the acetabular fragment. The peak pressure decreased gradually and increased again afterward, indicating the optimal transposition of the acetabular fragment. The postoperative peak pressure decreased to about 40% in the most improved case. This program allows the hip joint mechanics to be evaluated easily so that the advantages and disadvantages of various surgical methods can be examined biomechanically prior to surgery.

  12. Does Increased Coefficient of Friction of Highly Porous Metal Increase Initial Stability at the Acetabular Interface?

    PubMed

    Goldman, Ashton H; Armstrong, Lucas C; Owen, John R; Wayne, Jennifer S; Jiranek, William A

    2016-03-01

    Highly porous metal acetabular components illustrate a decreased rate of aseptic loosening in short-term follow-up compared with previous registry data. This study compared the effect of component surface roughness at the bone-implant interface and the quality of the bone on initial pressfit stability. The null hypothesis is that a standard porous coated acetabular cup would show no difference in initial stability as compared with a highly porous acetabular cup when subjected to a bending moment. Second, would bone mineral density (BMD) be a significant variable under these test conditions. In a cadaveric model, acetabular cup micromotion was measured during a 1-time cantilever bending moment applied to 2 generations of pressfit acetabular components. BMD data were also obtained from the femoral necks available for associated specimen. The mean bending moment at 150 μm was not found to be significantly different for Gription (24.6 ± 14.0 N m) cups vs Porocoat (25 ± 10.2 N m; P > .84). The peak bending moment tolerated by Gription cups (33.9 ± 20.3 N m) was not found to be significantly different from Porocoat (33.5 ± 12.2 N m; P > .92). No correlation between BMD and bending moment at 150 μm of displacement could be identified. The coefficient of friction provided by highly porous metal acetabular shells used in this study did not provide better resistance to migration under bending load when compared with a standard porous coated component. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Quantification of clearance and creep in acetabular wear measurements.

    PubMed

    Saffarini, Mo; Gregory, Thomas; Vandenbussche, Eric

    2016-04-01

    This study aimed to measure femoral head penetration before occurrence of real wear, and to quantify the portions attributable respectively to clearance and plastic deformations in various acetabular designs. We analyzed CT scans from 15 patients at 'day five' after total hip arthroplasty (THA). All patients received Exafit(®) femoral stems and 28 mm heads: 5 patients had cemented Durasul(®) all-PE cups, 5 patients had un-cemented Allofit(®) metal-backed cups, and 5 patients had un-cemented Stafit(®) dual-mobility cups. We also analyzed CT scans of samples of the three head-cup combinations to compare in vivo and in vitro measurements. The mean femoral head penetration measured on 'day five' was lower for all-PE cups (0.196 mm) than for metal-backed cups (0.551 mm) and dual-mobility cups (0.634 mm). The present study indicates that isolated measurements of femoral head penetration include 0.15-0.46 mm of radial clearance and 0.05-0.27 mm of creep, and confirms that the majority of so-called bedding-in observed in the first post-operative months is not entirely due to wear.

  14. Quantification of clearance and creep in acetabular wear measurements

    PubMed Central

    Gregory, Thomas; Vandenbussche, Eric

    2016-01-01

    Background This study aimed to measure femoral head penetration before occurrence of real wear, and to quantify the portions attributable respectively to clearance and plastic deformations in various acetabular designs. Methods We analyzed CT scans from 15 patients at ‘day five’ after total hip arthroplasty (THA). All patients received Exafit® femoral stems and 28 mm heads: 5 patients had cemented Durasul® all-PE cups, 5 patients had un-cemented Allofit® metal-backed cups, and 5 patients had un-cemented Stafit® dual-mobility cups. We also analyzed CT scans of samples of the three head-cup combinations to compare in vivo and in vitro measurements. Results The mean femoral head penetration measured on ‘day five’ was lower for all-PE cups (0.196 mm) than for metal-backed cups (0.551 mm) and dual-mobility cups (0.634 mm). Conclusions The present study indicates that isolated measurements of femoral head penetration include 0.15–0.46 mm of radial clearance and 0.05–0.27 mm of creep, and confirms that the majority of so-called bedding-in observed in the first post-operative months is not entirely due to wear. PMID:27162781

  15. Acetabular revision in THA using tantalum augments combined with impaction bone grafting.

    PubMed

    Gehrke, Thorsten; Bangert, Yannic; Schwantes, Bernd; Gebauer, Matthias; Kendoff, Daniel

    2013-01-01

    Acetabular revision with associated bone loss in uncontained defects can be difficult. We report preliminary results utilising a novel technique, combining tantalum-augments with allograft bone and cemented cups. Forty-six patients undergoing cup revision with a tantalum augment and allografting were clinically (HHS) and radiographically reviewed at an average of 46 months postoperatively. There were 28 type-2B and 18 type-3A Paprosky defects. Postoperative images were assessed for osteointegration, bone-remodelling and recreation of the native hip centre. The average patient age at time of acetabular revision was 65 years, with 18 male and 28 female patients. The HHS improved on average from 44 to 82 points. Correction of the high hip centre was possible in all patients with average medialisation of 10 mm and lowering of the hip centre by 14 mm. Four patients (four hips) sustained a hip dislocation postoperatively and one required revision. Two acetabular revisions were necessary after implantation, because of early cup loosening and failure of the construct. In one of these, the tantalum augment was found to be well fixed. Of the remaining hips, at latest radiographic follow-up, 44 tantalum implants were radiographically stable and osteointegrated. Non-progressive radiolucent lines were present around the acetabular component in two other hips. The combination of tantalum-augmentation with impaction allografting is a promising technique to manage severe uncontained acetabular defects.

  16. Total arthroplasty in displaced dysplastic hips with acetabular reconstruction and femoral shortening – technical note☆☆☆

    PubMed Central

    Silva, Paulo; de Oliveira, Leandro Alves; Coelho, Danilo Lopes; do Amaral, Rogério Andrade; Rebello, Percival Rosa; de Moraes, Frederico Barra

    2014-01-01

    To describe a new procedure of total hip replacement in patient with severe developmental dysplasia of the left hip, using technique of acetabular reconstruction with autogenous bone grafts and subtrochanteric shortening femoral osteotomy. Total hip replacement done in January of 2003. The Eftekhar's classification was used and included type D, neglected dislocations. Bone graft incorporated in acetabular shelf and femoral osteotomy. Our contribution is the use of an Allis plate to better fix acetabular grafts, avoiding loosening, and cerclage around bone graft in femoral osteotomy site, which diminish pseudoarthrosis risk. This technique shows efficiency, allowing immediately resolution for this case with pain and range of motion of hip improvement. It also allows the acetabular dysplasia reconstruction, equalization of the limb length (without elevated risk of neurovascular lesion) and repairs the normal hip biomechanics due to the correction of the hip's center of rotation. PMID:26229775

  17. Influence of cementless cup surface on stability and bone fixation 2 years after total hip arthroplasty.

    PubMed

    Urbański, Wiktor; Krawczyk, Artur; Dragan, Szymon Ł; Kulej, Mirosław; Dragan, Szymon F

    2012-01-01

    Loss of fixation between bone and implant surface is one of the main treatment problems in total hip arthroplasty. It might lead to implant instability, bone loss and treatment failure resulting in revision surgery. Surface modification is a method for improving bone response to implant and increasing implant osseointegration. However, the currently applied modifications such as hydroxyapatite coatings do not meet expectation and do not provide good clinical result. The object of the study was to evaluate the influence of acetabular cup surface modification on fixation and bone remodelling in total hip arthroplasty. Clinical and radiological outcomes were evaluated in patients two years after cementless total hip replacement. Two groups were compared: patients with acetabular component with uncoated titanium surface and patients with hydroxyapatite-coated acetabular surface. Hips X-rays were analysed for early signs of losing stability of acetabular cups. Two years after surgery the analysis of X-rays did not reveal any statistical differences in stability, migration of acetabular components of endoprosthesis between both groups. No differences were also observed in bone remodelling around implants. Particularly high percentage of cups, i.e. 17.64%, were classified into the group with high risk of early implant loosening, i.e., the group with HA coatings. Hydroxyapatite coatings on titanium cementless acetabular cups implanted by press-fit technique have no influence on their stability, bone-implant fixation and the remodelling of bone surrounding an implant two years after surgery.

  18. The Harris-Galante cementless acetabular component: results in 190 cases with at least 3 years follow-up.

    PubMed

    Claus, B; Van Innis, B; De Witte, E; Van Overschelde, J; Magotteaux, B; Fatemi, F; Vandepaer, F

    1993-01-01

    The results of 190 primary total hip arthroplasties with a Harris-Galante cementless acetabular cup were reviewed. All patients had a minimum follow-up of 3 years (range, 3 to 5.5 years, mean 46 months). Clinical and radiographical analysis was performed. Inguinal pain was recorded in five cases. We noted a fracture of a screw in four cases without further implications. There was no evidence of acetabular loosening. There was no migration of the acetabular cup. No acetabular component showed measurable wear of the polyethylene liner. Non-progressive radiolucent lines were recorded in 14% of the patients: among these patients, radiolucent lines were noted in zone 1 in 46%, in zone 2 in 4% and in zone 3 in 86%. Two socket revisions became necessary. One patient suffered a deep-seated infection. Another revision was necessary because of recurrent dislocation.

  19. Uncemented porous tantalum acetabular components: early follow-up and failures in 613 primary total hip arthroplasties.

    PubMed

    Noiseux, Nicolas O; Long, William J; Mabry, Tad M; Hanssen, Arlen D; Lewallen, David G

    2014-03-01

    Uncemented tantalum acetabular components were introduced in 1997. The purpose was to determine the 2- to 10-year results with this implant material in primary total hip arthroplasty. Our registry identified all primary total hip cases with porous tantalum cups implanted from 1997 to 2004. Clinical outcomes and radiographs were studied. 613 cases were identified. Seventeen percent of patients were lost to follow-up. Twenty-five reoperations were performed (4.4%). Acetabular cup removal occurred in 6 cases (1.2%). No cups were revised for aseptic loosening. Incomplete radiolucent lines were found on 9.3% of initial postoperative radiographs. At 2 years, 67% had resolved. Zero new radiolucent lines were detected. Two- to 10-year results of porous tantalum acetabular components for primary total hip arthroplasty demonstrate high rates of initial stability and apparent ingrowth. © 2014.

  20. Fixed-angle screws vs standard screws in acetabular prosthesis fixation: a cadaveric biomechanical study.

    PubMed

    Hugate, Ronald R; Dickey, Ian D; Chen, Qingshan; Wood, Christina M; Sim, Franklin H; Rock, Michael G

    2009-08-01

    Secure fixation of acetabular components in total hip arthroplasty can be challenging. The purpose of this study was to perform biomechanical analysis of cup fixation strength using fixed-angle vs standard screw fixation. Multihole, porous-backed acetabular prostheses were implanted in both acetabuli of 8 cadaveric pelves using standard press-fit techniques. Fixed-angle screws were used on the left side, and standard cancellous screws were used in the right. The use of fixed-angle screws enhanced acetabular fixation substantially under subfailure cyclic loading conditions and load-to-failure. The triradiate screw configuration increases the bending moment required to fail the specimens as well. Fixed-angle screws may be useful for achieving rigid fixation of acetabular prostheses in challenging clinical scenarios.

  1. Lateral acetabular labral length is inversely related to acetabular coverage as measured by lateral center edge angle of Wiberg

    PubMed Central

    Petersen, Brian D.; Wolf, Bryan; Lambert, Jeffrey R.; Clayton, Carolyn W.; Glueck, Deborah H.; Jesse, Mary Kristen; Mei-Dan, Omer

    2016-01-01

    Patients with developmental dysplasia of the hip often have compensatory labral hypertrophy, which presumably lends stability to an unstable joint. Conversely, patients with acetabular overcoverage may have small or ossified labra. The purpose of this study is to explore the interaction of labral length with the degree of acetabular hip coverage. A retrospective cohort of patients with hip pain presenting to a hip preservation center, who had undergone hip magnetic resonance imaging and AP pelvis radiographs were studied. General linear multivariate models were used to assess the association between three measures of labral length (lateral, anterior and anterior inferior locations along the acetabular rim) and the X-ray derived lateral center edge angle (LCEA) of Wiberg. Of the three acetabular labral locations measured, only the lateral labrum was associated with LCEA Wiberg (P = 0.0008). Lateral labral length increases as LCEA of Wiberg decreases. The anterior and anterior inferior labral locations did not show a predictable increase in labral length as LCEA Wiberg decreased. PMID:27583157

  2. Are porous tantalum cups superior to conventional reinforcement rings?

    PubMed Central

    Brüggemann, Anders; Fredlund, Erik; Mallmin, Hans; Hailer, Nils P

    2017-01-01

    Background and purpose— Porous tantalum cups have been introduced as an alternative to various reinforcement rings in revision hip surgery. We hypothesized that porous tantalum cups would be superior to Müller acetabular roof reinforcement rings (MARRs) in revision hip surgery with re-revision for aseptic loosening as the primary outcome measure. Patients and methods— 207 hips operated with either a porous tantalum cup (TM cup, n = 111) or a MARR (n = 96) at index procedure were identified in our local arthroplasty register. Acetabular defects were classified according to Paprosky. There were 96 men and 111 women with a median age of 71 (35–95) years, presenting acetabular defect size type I in 39 cases, IIA in 22, IIB in 27, IIC in 43, IIIA in 32, and IIIB in 37 cases. Analysis of medical records identified all patients with subsequent re-revision and reasons for re-revisions. Kaplan-Meier survival functions were used to estimate implant survival. Results— With re-revision for aseptic loosening as the endpoint, the 6-year unadjusted cumulative survival was 97% (95% CI: 94–100) for TM cups and 96% (CI: 92–100) for MARR (p = 0.6). Using re-revision for any reason as the endpoint, 6-year survival was 87% (CI: 81–94) for TM cups and 95% (CI: 90–99) for MARR (p = 0.06). The main reason for re-revision in the TM group was dislocation (n = 10), followed by loosening (n = 3), whereas the main reason for re-revision in the MARR group was aseptic loosening (n = 8). Duration of the index procedure and perioperative blood loss were lower in the TM group. Interpretation— Both TM and MARR lead to good 6-year results in acetabular revision surgery. The methods differ in their respective failure mechanisms. We conclude that TM cups are a valuable treatment option in acetabular revision surgery, but the reasons underlying dislocations after the use of TM cups must be analyzed further. PMID:27892748

  3. Are porous tantalum cups superior to conventional reinforcement rings?

    PubMed

    Brüggemann, Anders; Fredlund, Erik; Mallmin, Hans; Hailer, Nils P

    2017-02-01

    Background and purpose - Porous tantalum cups have been introduced as an alternative to various reinforcement rings in revision hip surgery. We hypothesized that porous tantalum cups would be superior to Müller acetabular roof reinforcement rings (MARRs) in revision hip surgery with re-revision for aseptic loosening as the primary outcome measure. Patients and methods - 207 hips operated with either a porous tantalum cup (TM cup, n = 111) or a MARR (n = 96) at index procedure were identified in our local arthroplasty register. Acetabular defects were classified according to Paprosky. There were 96 men and 111 women with a median age of 71 (35-95) years, presenting acetabular defect size type I in 39 cases, IIA in 22, IIB in 27, IIC in 43, IIIA in 32, and IIIB in 37 cases. Analysis of medical records identified all patients with subsequent re-revision and reasons for re-revisions. Kaplan-Meier survival functions were used to estimate implant survival. Results - With re-revision for aseptic loosening as the endpoint, the 6-year unadjusted cumulative survival was 97% (95% CI: 94-100) for TM cups and 96% (CI: 92-100) for MARR (p = 0.6). Using re-revision for any reason as the endpoint, 6-year survival was 87% (CI: 81-94) for TM cups and 95% (CI: 90-99) for MARR (p = 0.06). The main reason for re-revision in the TM group was dislocation (n = 10), followed by loosening (n = 3), whereas the main reason for re-revision in the MARR group was aseptic loosening (n = 8). Duration of the index procedure and perioperative blood loss were lower in the TM group. Interpretation - Both TM and MARR lead to good 6-year results in acetabular revision surgery. The methods differ in their respective failure mechanisms. We conclude that TM cups are a valuable treatment option in acetabular revision surgery, but the reasons underlying dislocations after the use of TM cups must be analyzed further.

  4. Midterm Outcome of Cementless Total Hip Arthroplasty in Crowe IV-Hartofilakidis Type III Developmental Dysplasia of the Hip.

    PubMed

    Mu, Wenbo; Yang, Desheng; Xu, Boyong; Mamtimin, Askar; Guo, Wentao; Cao, Li

    2016-03-01

    Developmental dysplasia of the hip (DDH) is widespread in developing countries, and treating Crowe IV-Hartofilakidis Type III DDH in adults requires the use of a highly demanding technique. We sought to determine the outcome of cementless total hip arthroplasty using Zweymüller components to treat Crowe IV-Hartofilakidis Type III DDH. Fifty-eight patients (71 hips) with a mean age of 35.8 years at time of index operation were included in our study. The average duration of follow-up was 70.5 months. The acetabular component was placed in the true acetabulum in all cases, and subtrochanteric shortening osteotomy was performed in 61 hips. With any component revision for any reason as the end point, Kaplan-Meier survivorship analysis at 98 months revealed a cumulative survival rate for implanted components of 91.40%. The mean Harris Hip Score improved from 35.6 preoperatively to 82.9 postoperatively. There were 20 cases of intraoperative fracture, 1 case of complete nerve palsy, and 7 cases of transient nerve palsy. Revision surgery was performed in 7 patients because of cup loosening in 1, severe polyethylene wear in 4, cup breakage in 1, and dislocation in 1. Midterm results for cementless total hip arthroplasty in patients with Crowe IV-Hartofilakidis Type III DDH was satisfactory; however, intraoperative fracture and polyethylene wear were major complications. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. [Analysis of migration of screwed acetabular components following revision arthroplasty of the hip joint. Results of single-image roentgen analysis].

    PubMed

    Dihlmann, S W; Ochsner, P E; Pfister, A; Mayrhofer, P

    1994-01-01

    Out of 57 revised acetabular components, which were regularly checked, 47 had been replaced by a cemented Müller's acetabular reinforcement ring resp. a cementless Müller's Sl-shell with flange. Both types of cups are anchored in the acetabular roof with cancellous bone screws (tab. 1). 42 cases with radiograph series permitted a detailed analysis with the EBRA-method, a computer aided method for the evaluation of acetabular spatial migration based on standard radiographs of the pelvis. The clinical results were very satisfying (tab. 6). The screwed acetabular components migrated little, although, some essential displacements of the center of rotation (in relation to the anatomical position) had to be accepted. As was recognizable with today's inaccurate methods of measuring the center of the head, the displacement too far towards cranial influenced the migration tendency less than an excessive lateralisation. Especially satisfying is the fact, that no increased migration was observed after reconstruction bone grafting of severe acetabular defects, provided that at least a partly direct contact between the acetabular component and the original bone stock was obtained. For the first time EBRA shall be introduced here as a method which shows the migration and the spatial inclination of the acetabular cup in a vector chart.

  6. Porous Tantalum Buttress Augments for Severe Acetabular Posterior Column Deficiency.

    PubMed

    Meneghini, R Michael; Hull, Jason R; Russo, Glenn S; Lieberman, Jay R; Jiranek, William A

    2015-11-01

    In revision total hip arthroplasty (THA), consensus is lacking regarding the optimal method for reconstruction of the most severe acetabular defects. Porous tantalum (TM) buttress augments were designed for the most severe postero-superior defects. The purpose of this study was to report the results of a consecutive series of acetabular reconstructions utilizing TM buttress augments. Eight complex acetabular reconstructions utilizing a TM buttress augment were performed at two centers. All were Paprosky 3A or Paprosky 3B bone loss classification, with severe superior and posterior column deficiency where wedge augments were insufficient for mechanical support. The acetabular cup sizes ranged from 64-78, and a buttress shim was used in 7 of 8 cases. Clinical and radiographic follow-up averaged 16.5 months (range, 10-28) and no cases were lost to follow-up. There were no cases of clinical or radiographic loosening, and no case had required reoperation or revision. All patients except one were ambulating with either no assist device or a single cane at final follow-up. There was one complication of an iliac wing fracture noted incidentally on postoperative x-rays in the lone patient in whom a buttress shim was not used. At short-term follow-up, TM acetabular buttress augments appear to effectively substitute for the use of structural allografts or cages, which would otherwise be used in this challenging setting. The potential for biologic fixation is promising for the durability of these reconstructions; however, longer-term follow-up is required for full evaluation.

  7. Evaluating the accuracy of wear formulae for acetabular cup liners.

    PubMed

    Wu, James Shih-Shyn; Hsu, Shu-Ling; Chen, Jian-Horng

    2010-02-01

    This study proposes two methods for exploring the wear volume of a worn liner. The first method is a numerical method, in which SolidWorks software is used to create models of the worn out regions of liners at various wear directions and depths. The second method is an experimental one, in which a machining center is used to mill polyoxymethylene to manufacture worn and unworn liner models, then the volumes of the models are measured. The results show that the SolidWorks software is a good tool for presenting the wear pattern and volume of a worn liner. The formula provided by Ilchmann is the most suitable for computing liner volume loss, but is not accurate enough. This study suggests that a more accurate wear formula is required. This is crucial for accurate evaluation of the performance of hip components implanted in patients, as well as for designing new hip components.

  8. A comparative study of the posterolateral and anterolateral approaches for isolated acetabular revision.

    PubMed

    Park, Youn-Soo; Moon, Young-Wan; Lim, Byung-Ho; Shon, Min-Soo; Lim, Seung-Jae

    2011-07-01

    Although isolated revision of the acetabular component has become an increasingly common option for revision hip surgery, opinions differ regarding the ideal surgical approach for reducing postoperative instability. The purpose of this study was to compare the clinical and radiographic results of isolated acetabular revision performed using a posterolateral and an anterolateral approach. The authors retrospectively compared the clinical and radiographic results of isolated acetabular revision performed in 33 hips using a posterolateral approach with those performed in 36 hips using an anterolateral approach. All procedures were performed by a single surgeon and all patients received the same postoperative protocol. Mean duration of follow-up was 4.6 years (range 2-13.2). Mean postoperative Harris hip scores were similar in the posterolateral and anterolateral groups (86.5 and 87.2 points, respectively). In the entire series of 69 hips, 6 (9%) underwent re-revision of the acetabular component because of aseptic cup loosening in 4, recurrent dislocation in 1, and deep infection in 1. No significant difference was found between the two groups with respect to complication or re-revision rates, but the dislocation rate in the anterolateral approach group was significantly lower than that in the posterolateral group (0 vs. 12%, p = 0.047). Isolated acetabular revision performed using an anterolateral approach seems to be the more viable option in selected patients, and in particular, it has a significantly lower postoperative dislocation rate than posterolateral acetabular revision.

  9. [Acetabular reconstruction in revision arthroplasty. Retrospective study of 76 cases. Hospital Español de México].

    PubMed

    Trueba Davalillo, Cesáreo; Gil Orbazo, Félix; Reyes Marco, Fernando; Minueza Mejía, Tomás; Navarrete Alvarez, José Mario

    2007-01-01

    To review our experience with the various acetabular reconstruction techniques used during revision arthroplasty based on the defect in each patient. We undertook a retrospective, descriptive, observational study of patients who underwent acetabular reconstruction during revision ar. throplasty, from January 1997 to January 2005. We documented the type of acetabular defect, the type of cup and graft used, the complications, and the pre- and postoperative assessment with the Harris scale. Data were analyzed with the SPSS software and the Wilcoxon test (p < 0.05). Seventy-six patients underwent surgery. Mean time elapsed between the primary replacement and the revision was 5 years. The acetabular defects found were: 16 type I, 22 type II, 30 type IIIA, and 8 type IIIB. The mean Harris score was 44 preoperatively and 76 postoperatively. The most frequently used technique involved the use of an autograft, a structural allograft with a porous threaded cup or a reinforcement ring. The most common complications included dislocation 5%, infection 3%, graft loss and cup loosening 21%, and loss of the hip center of rotation 15% (p < 0.05). Acetabular reconstruction is technically challenging and involves high failure and complication rates, thus providing little improvement in patient activity. It is important to restore the hip center of rotation to improve function. The reconstruction techniques we used are the most common ones and are described in the literature.

  10. Use of jumbo cups for revision of acetabulae with large bony defects.

    PubMed

    Gustke, Kenneth A; Levering, Melissa F; Miranda, Michael A

    2014-01-01

    Several methods of treatment are available for acetabular revision associated with bone loss. Jumbo cups (minimum diameter of 62 mm in women, 66 mm in men, or 10 mm larger than the normal contralateral acetabulum) are often useful for large defects. The purpose of this study is to report a large jumbo cup series with an average 10-year follow-up. A total of 196 jumbo cups in 186 patients with a minimum of 2-year follow-up were available for review. Harris hip score improved from 44 preoperatively to 72 postoperatively. Survivorship was 98% at 4 years and 96% at 16 years. Five revisions and two resection arthroplasties were performed for failure. In conclusion, porous jumbo cup acetabular revision with supplemental screw fixation provides good to excellent intermediate- and long-term outcomes.

  11. What is the Fate of Total Hip Arthroplasty (THA) Acetabular Component Orientation When Evaluated in the Standing Position?

    PubMed

    Tiberi, John V; Antoci, Valentin; Malchau, Henrik; Rubash, Harry E; Freiberg, Andrew A; Kwon, Young-Min

    2015-09-01

    This retrospective study measured the change of the acetabular component orientation between supine and standing radiographs in 113 THA patients and identified the associated anatomical parameters that may help direct pre-operative planning. The mean change of the acetabular component inclination and version from supine to standing was 4.6° and 5.9° respectively (P<0.0001), with 49 (43%) hips showing inclination change >5° and 69 (53%) hips showing version change >5°. Twelve (43%) of 28 'malpositioned' cups became 'well-positioned' and 26 (31%) of 85 'well-positioned' cups became 'malpositioned' upon standing. Changes in inclination were associated with leg length discrepancy and pelvic obliquity; and changes in version were associated with pelvic tilt and pelvic incidence. Standing position and patient factors should be considered when defining "optimal" acetabular orientation.

  12. [Biological acetabular defect reconstruction in revision hip arthroplasty using impaction bone grafting and an acetabular reconstruction ring].

    PubMed

    Friedrich, M J; Gravius, S; Schmolders, J; Wimmer, M D; Wirtz, D C

    2014-04-01

    improvement in the average Harris Hip Score (82.2 ± 8.7 vs. 44.7 ± 10.7) and the Merle d'Aubigné Score (14.6 ± 1.9 vs. 7.5 ± 1.3). Radiological solid osseointegration of the cup was observed in 21 cases; partial radiolucent lines were seen in 2 cases (9 %) in the zones I-III delineated by DeLee and Charnley. In 21 cases (91 %) radiographs confirmed no measurable migration or displacement of the acetabular component and the bone graft was determined to be incorporated on the basis of osseous consolidation within the grafted area in 20 cases (87 %). During follow-up 3 prosthesis (13 %) required revision.

  13. Ectodermal dysplasias.

    PubMed

    Itin, Peter H; Fistarol, Susanna K

    2004-11-15

    Ectodermal dysplasias are a large group of heritable conditions characterized by congenital defects of one or more ectodermal structures and their appendages: hair (hypotrichosis, partial, or total alopecia), nails (dystrophic, hypertrophic, abnormally keratinized), teeth (enamel defect or absent), and sweat glands (hypoplastic or aplastic). The ectodermal dysplasias, as a rule, are not pure "one-layer diseases." Mesodermal and, rarely, endodermal dysplasias coexist. Embryogenesis exhibits distinct tissue organizational fields and specific interactions among the germ layers that may lead to a wide range of ectodermal dysplasias when genes important for development are mutated or otherwise altered in expression. Of the approximately 200 different ectodermal dysplasias, about 30 have been studied at the molecular level with identification of the causative gene. Freire-Maia and Pinheiro used the clinical aspects for their classification, and Priolo integrated molecular genetic and clinical aspects for her scheme. Those two more historical classification schemes have the difficulty that, when applied strictly, several additional groups of diseases should be integrated within the term "ectodermal dysplasias," e.g. keratodermas with skin or hair alterations or the ichthyoses with associated features. Such consequent classification would lead to an endless list of diseases and would be useless for the practical work. Recent evidence implicates a genetic defect in different pathways orchestrating ectodermal organogenesis. Modern molecular genetics will increasingly elucidate the basic defects of the different syndromes and yield more insight into the regulatory mechanisms of embryology. In this way, a reclassification of ectodermal dysplasias will be possible according to the function of their involved mutated genes. Lamartine recently proposed a helpful classification according to the functions of the genes discovered in different types of ectodermal dysplasias

  14. Isolated acetabular revision with femoral stem retention after bipolar hip arthroplasty.

    PubMed

    Kaku, Nobuhiro; Tabata, Tomonori; Tagomori, Hiroaki; Tsumura, Hiroshi

    2017-03-01

    In bipolar hemiarthroplasty, migration of the outer cup component into the acetabular cup, with evidence of severe osteolysis in the acetabulum, commonly occurs without loosening of the femoral component. The merits of retaining the stable femoral component in these cases have been debated. Our study aimed to determine whether revision of the acetabular component in isolation could be successfully performed. The data of 54 patients (61 hips), 44 women, and 10 men, aged 67.7 (range 47-86) years at the time of the index revision, were analyzed. The average time from primary operation to revision surgery was 14.9 (range 1.0-27.0) years, with an average follow-up time after revision of 5.2 (range, 1.0-18.7) years. Indications for acetabular revision included migration of the outer cup component (N = 55), disassembly of the bipolar cup (N = 4), and recurrent dislocation (N = 2). Fixation of the femoral stem was cementless in 49 hips and cemented in 12. Bone grafting for osteolysis of the proximal femur around the stem was performed in six hips. An acetabular reinforcement ring with a cemented cup was used in 31 hips, with cementless cup fixation in 29 hips, and cemented cup in one case. On average, the Harris hip score improved from 57.0 ± 21.6 to 87.4 ± 6.40 points after revision. Two cases of femoral periprosthetic fracture were treated with osteosynthesis 3 year post-revision. There was no evidence of loosening of the femoral stem or subsidence, with a non-progressive radiolucent line <2 mm identified in one case. There was no incidence of dislocation or deep infection, and all components were judged to be stable at the final follow-up. Isolated acetabular revision can be reliably performed in cases of failed bipolar hemiarthroplasty with a well-fixed femoral component.

  15. Total hip arthroplasty using the Wroblewski golf ball cup inserted through the posterior approach. A high rate of dislocation.

    PubMed

    Porter, P; Stone, M H

    2004-07-01

    The Wroblewski golf ball acetabular cup was introduced by surgeons using the trochanteric osteotomy approach for revision total hip replacement (THR) in order to reduce the rate of dislocation. We have routinely used the Ogee long posterior wall (Ogee LPW) and the Wroblewski angle bore cups in THR. Although the new Wroblewski golf ball cup performed well there was a significant early rate of dislocation of 20%. Our rate of dislocation over a period of ten years using the Ogee LPW and Wroblewski angle bore cups had been 0.52%. We present our findings and an investigation as to why the new cup has such a high rate of dislocation when used with the posterior approach. We show that a relatively small change in the design of the acetabular component resulted in significant adverse clinical results.

  16. Fibromuscular Dysplasia

    MedlinePlus

    ... for this author on this site Article Figures & Tables Info & Metrics eLetters Jump to Article What Is ... Are Available for Patients With FMD? Disclosures Figures & Tables Info & Metrics eLetters fibromuscular dysplasia patient education peripheral ...

  17. Use of porous tantalum for acetabular reconstruction in revision hip arthroplasty.

    PubMed

    Issack, Paul S

    2013-11-06

    ➤ Over the past decade, porous tantalum has emerged as a powerful tool for reconstruction of the failed acetabular component.➤ The increased porosity, high coefficient of friction, and favorable elastic modulus of porous tantalum compared with traditional titanium mesh or cobalt chromium acetabular components allow for greater bone ingrowth potential, implant stability, and host bone preservation, respectively, in porous tantalum shells.➤ Several studies have confirmed the excellent early and midterm results of porous tantalum reconstruction for revision hip arthroplasty.➤ Depending on the degree of bone loss, excellent results have been achieved with modular or revision porous tantalum shells, tantalum shells with tantalum augments, and cup-cage constructs.➤ These implants and techniques are greatly changing the approach to acetabular revision surgery and are providing constructs with greater stability and more physiologic biomechanical properties than those achieved through the use of traditional reconstructive methods.

  18. Use of iPhone technology in improving acetabular component position in total hip arthroplasty.

    PubMed

    Tay, Xiau Wei; Zhang, Benny Xu; Gayagay, George

    2017-09-01

    Improper acetabular cup positioning is associated with high risk of complications after total hip arthroplasty. The aim of our study is to objectively compare 3 methods, namely (1) free hand, (2) alignment jig (Sputnik), and (3) iPhone application to identify an easy, reproducible, and accurate method in improving acetabular cup placement. We designed a simple setup and carried out a simple experiment (see Method section). Using statistical analysis, the difference in inclination angles using iPhone application compared with the freehand method was found to be statistically significant (F[2,51] = 4.17, P = .02) in the "untrained group". There is no statistical significance detected for the other groups. This suggests a potential role for iPhone applications in junior surgeons in overcoming the steep learning curve.

  19. Effectiveness of an Acetabular Positioning Device in Primary Total Hip Arthroplasty

    PubMed Central

    Hendrix, Stephen L.; Mologne, Timothy S.; Peterson, Drew A.; Holley, Keith A.

    2005-01-01

    To evaluate the efficacy of a commercially available acetabular positioning device, we performed a prospective evaluation of 40 consecutive patients undergoing primary total hip arthroplasty. All surgery was performed by the same surgeon, in the same operating room, and on the same operating table. The acetabular positioning device was designed to place the component in 45° of abduction. At 6 weeks, all radiographs were evaluated by 3 investigators not involved with the surgery. Each radiograph was evaluated by each reviewer on 3 separate occasions, blinded to the findings of the other reviewer to assess interobserver and intraobserver variability. The mean cup abduction angle was 42.1°, with a range from 23° to 57° (SD 8.3°). Intraobserver and interobserver variability were 0.2 and 0.3°, respectively. The findings of this study demonstrate a wide variability in acetabular cup placement in primary total hip arthroplasty. We believe this is due to movement of the pelvis, which may occur during preparation, draping, and retracting during surgery. We feel surgeons should not rely solely on positioning devices when implanting the acetabular component in total hip arthroplasty. Identification of bone landmarks and determination of superolateral implant coverage noted on preoperative templating is advocated to improve the precision of component position. PMID:18751812

  20. Removal of well-fixed, cementless, acetabular components in revision hip arthroplasty.

    PubMed

    Mitchell, P A; Masri, B A; Garbuz, D S; Greidanus, N V; Wilson, D; Duncan, C P

    2003-09-01

    Removal of well-fixed, cementless, acetabular components during revision arthroplasty remains a challenging problem. Further damage to host bone may limit options for reconstruction and compromise the long-term result of the revision operation. We report the results of 31 hips with well-fixed, cementless sockets which were removed using a new cup extraction system. In all hips the socket was removed without difficulty and with minimal further bone loss.

  1. Migration pattern of cementless press fit cups in the presence of stabilizing screws in total hip arthroplasty

    PubMed Central

    2011-01-01

    The aim of this study was to evaluate the initial acetabular implant stability and late acetabular implant migration in press fit cups combined with screw fixation of the acetabular component in order to answer the question whether screws are necessary for the fixation of the acetabular component in cementless primary total hip arthroplasty. One hundred and seven hips were available for follow-up after primary THA using a cementless, porous-coated acetabular component. A total of 631 standardized radiographs were analyzed digitally by the "single-film-x-ray-analysis" method (EBRA). One hundred 'and one (94.4%) acetabular components did not show significant migration of more than 1 mm. Six (5.6%) implants showed migration of more than 1 mm. Statistical analysis did not reveal preoperative patterns that would identify predictors for future migration. Our findings suggest that the use of screw fixation for cementless porous- coated acetabular components for primary THA does not prevent cup migration. PMID:21486725

  2. Body mass index and acetabular component position in total hip arthroplasty.

    PubMed

    McBride, Andrew; Flynn, Jennifer; Miller, George; Barnes, Matthew; Mackie, Scott

    2013-03-01

    Correct acetabular component positioning during total hip arthroplasty affects the restoration of normal biomechanics, component wear and failure rates. This study examined whether a patient's body mass index (BMI) affects the accuracy of acetabular component placement in terms of the post-operative abduction angle. This was a retrospective review of 102 total hip arthroplasties performed from May 2009 in a single institution. The acetabular abduction angle was measured on the post-operative radiographs of the included patients. Statistical analysis of variance and t-tests were performed using Microsoft Excel to compare the mean abduction angles of patients grouped according to their BMI. Comparison of the mean abduction angle between those with BMI < 25 and BMI > 25 showed a statistically significant difference (P = 0.003). Analysis of variance between all BMI groups was statistically significant (P = 0.01). Patients in the lowest centile of abduction angle had an average BMI of 28. Patients in the highest centile of abduction angle had an average BMI of 33. This study shows that patients with a normal BMI tend to have smaller abduction angles. Overweight or obese patients, on average, have a normal abduction angle but are more likely to have an 'open cup'. A number of factors unique to obese and overweight patient may contribute to an 'open cup' and less accurate cup placement. © 2012 The Authors. ANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons.

  3. Pelvic Incidence: A Predictive Factor for Three-Dimensional Acetabular Orientation—A Preliminary Study

    PubMed Central

    Bollini, Gérard; Legaye, Jean; Tardieu, Christine; Prat-Pradal, Dominique; Chabrol, Brigitte; Jouve, Jean-Luc; Duval-Beaupère, Ginette; Pélissier, Jacques

    2014-01-01

    Acetabular cup orientation (inclination and anteversion) is a fundamental topic in orthopaedics and depends on pelvis tilt (positional parameter) emphasising the notion of a safe range of pelvis tilt. The hypothesis was that pelvic incidence (morphologic parameter) could yield a more accurate and reliable assessment than pelvis tilt. The aim was to find out a predictive equation of acetabular 3D orientation parameters which were determined by pelvic incidence to include in the model. The second aim was to consider the asymmetry between the right and left acetabulae. Twelve pelvic anatomic specimens were measured with an electromagnetic Fastrak system (Polhemus Society) providing 3D position of anatomical landmarks to allow measurement of acetabular and pelvic parameters. Acetabulum and pelvis data were correlated by a Spearman matrix. A robust linear regression analysis provided prediction of acetabulum axes. The orientation of each acetabulum could be predicted by the incidence. The incidence is correlated with the morphology of acetabula. The asymmetry of the acetabular roof was correlated with pelvic incidence. This study allowed analysis of relationships of acetabular orientation and pelvic incidence. Pelvic incidence (morphologic parameter) could determine the safe range of pelvis tilt (positional parameter) for an individual and not a group. PMID:25006461

  4. Does Orientation of the Femoral Head Affect Acetabular Development? An Experimental Study in Lamb.

    PubMed

    Moraleda, Luis; Bravo, Christian; Forriol, Francisco; Albiñana, Javier

    2017-03-21

    Derotational osteotomy of the proximal femur has proved to be effective in the treatment of residual acetabular dysplasia. However, the reason why this osteotomy is effective remains debatable. The purpose of this study is to investigate if an alteration of femoral head orientation affects acetabular growth. A proximal femoral osteotomy was performed in 21 lambs aged 3 months: 5 varus osteotomies (110 degrees), 4 valgus osteotomies (150 degrees), and 12 derotation osteotomies. Results were compared with a control group (5 animals). Osteotomy was fixed with a screw-plate device. Version was controlled intraoperatively with K-wires. Animals were killed 3 months after surgical procedure. A morphometric study of both proximal femur and acetabulum was performed, including deepness, volume and diameters of the acetabulum, neck-shaft angle and femoral version. The average neck-shaft angle for the normal, anteversion, and retroversion groups was 129 degrees, whereas it was 110 degrees for the varus group and 149 degrees for the valgus group. The average femoral version for the normal, valgus, and varus groups was 21 degrees of anteversion, whereas it was 38 degrees of anteversion for the so-called anteversion group and 17 degrees of retroversion for the retroversion group. Nor the neck-shaft angle, nor the femoral version correlated with the acetabular anteroposterior diameter (P=0.698, 0.6, respectively), the acetabular inferosuperior diameter (P=0.083, 0.451, respectively) or the acetabular deepness (P=0.14, 0.371, respectively). The neck-shaft angle correlated significantly with acetabular volume (P=0.023), so that the lower the neck-shaft angle, the higher the acetabular volume (r=-0.453). The femoral version did not correlated with acetabular volume (P=0.381). Decreasing the neck-shaft angle provokes an increase in acetabular volume, whereas changes in femoral version do not affect the acetabular growth. Extra-articular osteotomies that alter femoral orientation

  5. Cross-sectional Anatomy of Ilium for Guiding Acetabular Component Placement Using High Hip Center Technique in Asian Population

    PubMed Central

    Xiao, Jian-Lin; Zuo, Jian-Lin; Liu, Peng; Qin, Yan-Guo; Li, Xue-Zhou; Liu, Tong; Gao, Zhong-Li

    2015-01-01

    Background: Many clinical studies have been published involving the use of a high hip center (HHC), achieved good follow-up. However, there is a little anatomic guidance in the literature regarding the amount of bone stock available for initial implant coverage in this area of the ilium. The purpose of this study was to evaluate the thickness and width of the human ilium and related acetabular cup coverage for guiding acetabular component placement in HHC. Methods: A total of 120 normal hips in 60 cases of adult patients from lower extremities computer tomographic angiography Digital Imaging and Communications in Medicine data were chosen for the study. After importing the data to the mimics software, we chose the cross sections every 5-mm increments from the rotational center of the hip to the cephalic of the ilium according the body sagittal axis, then we measured the thickness and width of the ilium for each cross section in axial plane, calculated the cup coverage at each chosen section. Results: At the acetabular dome, the mean thickness and width of the ilium were 49.71 ± 4.88 mm and 38.92 ± 3.67 mm, respectively, whereas at 1 cm above the dome, decreased to 41.35 ± 5.13 and 31.13 ± 3.37 respectively, and 2 cm above the dome, decreased to 31.25 ± 4.04 and 26.65 ± 3.43, respectively. Acetabular cup averaged coverage for 40-, 50-, and 60-mm hemispheric shells, was 100%, 89%, and 44% at the acetabular dome, 100%, 43.7%, and 27.5% for 1 cm above the dome, and 37.5%, 21.9%, and 14.2% for 2 cm above the dome. Conclusions: HHC reconstructions within 1 cm above the acetabular dome will be an acceptable and smaller diameter prosthesis would be better. PMID:26063357

  6. [Dysplasia in the development of the hip].

    PubMed

    Moraleda, L; Albiñana, J; Salcedo, M; Gonzalez-Moran, G

    2013-01-01

    Developmental dysplasia of the hip (DDH) causes anatomical changes that cause early coxarthrosis. Although risf factors have been determined, the aetiology and physiopathology remains exactly unknown. Neonatal screening with physical examination and ultrasound have been stablished in order to diagnose this disease early in life. A diagnosis in the first months of life is essential as it enables a normal hip to form and prevent the appearance of early coxarthrosis. Treatment principles are to be able to reduce the hip without provoking avascular necrosis of the femoral head, and to normalize the acetabular development. Knowledge of the orthopaedic and surgical options is essential in order to achieve success in the treatment.

  7. Treatment of periprosthetic acetabular fractures after previous hemi- or total hip arthroplasty: Introduction of a new implant.

    PubMed

    Resch, H; Krappinger, D; Moroder, P; Blauth, M; Becker, J

    2016-04-01

    Treatment of displaced periprosthetic acetabular fractures in elderly patients. The goal is to stabilize an acetabular fracture independent of the fracture pattern, by inserting the custom-made roof-reinforcement plate and starting early postoperative full weight-bearing mobilization. Acetabular fracture with or without previous hemi- or total hip arthroplasty. Non-displaced acetabular fractures. Watson-Jones approach to provide accessibility to the anterior and supraacetabular part of the iliac bone. Angle-stable positioning of the roof-reinforcement plate without any fracture reduction. Cementing a polyethylene cup into the metal plate and restoring prosthetic femoral components. Full weight-bearing mobilization within the first 10 days after surgery. In cases of two column fractures, partial weight-bearing is recommended. Of 7 patients with periprosthetic acetabular fracture, 5 were available for follow-up at 3, 6, 6, 15, and 24 months postoperatively. No complications were recognized and all fractures showed bony consolidation. Early postoperative mobilization was started within the first 10 days. All patients except one reached their preinjury mobility level. This individual and novel implant is custom made for displaced acetabular and periprosthetic fractures in patients with osteopenic bone. It provides a hopeful benefit due to early full weight-bearing mobilization within the first 10 days after surgery. In case of largely destroyed supraacetabular bone or two-column fractures according to Letournel additional synthesis via an anterior approach might be necessary. In these cases partial weight bearing is recommended.

  8. Intraoperative Arthrogram Predicts Residual Dysplasia after Successful Closed Reduction of DDH.

    PubMed

    Zhang, Zhong-Li; Fu, Zhe; Yang, Jian-Ping; Wang, Kan; Xie, Li-Wei; Deng, Shu-Zhen; Chen, Zhao-Qiang

    2016-08-01

    To determine the incidence of residual dysplasia after closed reduction (CR) of developmental dysplasia of the hip (DDH) and assess correlations between quality of arthrogram-guided CR and residual dysplasia using a new intraoperative radiographic criterion. Data of a consecutive series of 126 patients with DDH in 139 hips treated at our institution by arthrogram-guided CR from March 2006 to June 2013 were reviewed in this retrospective study. There were 23 boys and 103 girls with 88 affected left hips and 51 right hips. The average age at closed reduction was 14 months (range, 7-19 months) and average duration of follow-up 36 months (range, 24-100 months). Femoral head coverage (FHC) and arthrography type (A/B/C) on best reduced arthrographic images, acetabular index (AI) and Wiberg Center-Edge (CE) angle on anteroposterior (AP) pelvis radiograph at latest follow-up were measured. Residual hip dysplasia was determined according to the Harcke acetabular dysplasia radiographic standard. Patients were divided into non-late acetabular dysplasia (non-LACD) and late acetabular dysplasia (LACD) groups according to final results and age at reduction, sex and side compared between these two groups. Correlations between FHC and arthrography type and residual hip dysplasia were analyzed. Multiple logistic regression analysis was used to analyze sex, AI at CR, arthrography type and FHC with LACD. Receiver operating characteristic (ROC) curve analysis was used to determine the cutoff value for FHC. Forty-five of 139 hips (32.4%) had residual hip dysplasia. Avascular necrosis of the femoral head occurred in 11 hips (7.9%), nine of which had acetabular dysplasia. There were no significant differences between the two groups in age at reduction, sex or side. FHC differed significantly between the two groups (51.2% ± 15.3% vs . 28.5% ± 15.9%, t = 4.718, P = 0.000). A significantly greater percentage of the arthrography Type C group than Type A and B groups had LACD (χ(2) = 17

  9. Morphometric assessment of hip dysplasia in a cat treated by juvenile pubic symphysiodesis.

    PubMed

    Lai, Alen; Culvenor, John; Bailey, Craig

    2016-09-20

    To quantitatively evaluate the change of the coxofemoral joints using computed tomography and distraction index in a cat with hip dysplasia treated by juvenile pubic symphysiodesis. Case report. Eighteen-week-old female entire Maine Coon cat. Juvenile pubic symphysiodesis resulted in changes in the distraction index, acetabular angle, dorsal acetabular rim angle, dorsal acetabular sector angle, and clinical improvement at the six month follow-up. No intra-operative or postoperative complications were recorded. Juvenile pubic symphysiodesis performed at 18 weeks of age resulted in improvement in hip joint conformation and hip laxity in a dysplastic cat. Juvenile pubic symphysiodesis may be a promising treatment for feline hip dysplasia and is a safe and technically simple procedure to perform. Further investigations are warranted.

  10. Endoscopic Shelf Acetabuloplasty Combined With Labral Repair, Cam Osteochondroplasty, and Capsular Plication for Treating Developmental Hip Dysplasia

    PubMed Central

    Uchida, Soshi; Wada, Takahiko; Sakoda, Shinsuke; Ariumi, Akihiro; Sakai, Akinori; Iida, Hirokazu; Nakamura, Toshitaka

    2014-01-01

    In addition to the underlying shallow acetabular deformity, a patient with hip dysplasia has a greater risk of development of a labral tear, a cam lesion, and capsular laxity. This combination of abnormalities exacerbates joint instability, ultimately leading to osteoarthritis. Unsurprisingly, only repairing the acetabular labrum remains controversial, and the outcome is unpredictable. In this technical note, with video, we demonstrate an entirely endoscopic approach for simultaneously repairing the most common mechanical abnormalities found in moderate hip dysplasia: labral repair, cam osteochondroplasty, capsular plication, and shelf acetabuloplasty using an autologous iliac bone graft. PMID:24749043

  11. Efficiency and Accuracy of Bernese Periacetabular Osteotomy for Adult Hip Dysplasia

    PubMed Central

    Luo, Dian‐zhong; Xiao, Kai; Cheng, Hui

    2015-01-01

    Bernese periacetabular osteotomy (PAO) has several advantages dealing with adolescents and adults acetabular dysplasia. The authors introduced the details and steps performing PAO, with attached video and schematic diagram which demonstrates a perfect PAO in efficiency and accuracy. The patient is an 18‐year‐old girl, complaining hip pain on the left side for 6 months. Physical examination shows normal gait and range of motion (ROM) of the left hip. Pelvic anteroposterior X‐ray shows acetabular dysplasia on the left, and post operation on the right. She is very satisfied with the PAO on the right one year before, so we recommend PAO for the left hip dysplasia again. The key point of PAO includes 4 cuts: ischial cut, pubic cut, acetabular roof cut, and quadrilateral bone cut, and the four cuts should be accomplished accurately. Then the acetabular fragment should be turned to ideal position with the lateral CE angle (LCE) > 25°, the Tönnis acetabular angle 0°, the anterior CE angle (ACE) > 20°, good congruence joint space, and with the hip center medialized slightly. At lastly the acetabular fragment is fixed with proper nails and instruments. The patient is very happy to the surgery with no hip pain, with normal gait, ROM, and Harris hip scores (HHS). In summary, PAO is a relative new and efficient procedure for adult hip dysplasia, requiring accurate techniques. Cadaveric practice and familiar with the local anatomy can help the surgeon overcome the learning curve quickly. PMID:26791326

  12. Efficiency and Accuracy of Bernese Periacetabular Osteotomy for Adult Hip Dysplasia.

    PubMed

    Luo, Dian-zhong; Zhang, Hong; Xiao, Kai; Cheng, Hui

    2015-11-01

    Bernese periacetabular osteotomy (PAO) has several advantages dealing with adolescents and adults acetabular dysplasia. The authors introduced the details and steps performing PAO, with attached video and schematic diagram which demonstrates a perfect PAO in efficiency and accuracy. The patient is an 18-year-old girl, complaining hip pain on the left side for 6 months. Physical examination shows normal gait and range of motion (ROM) of the left hip. Pelvic anteroposterior X-ray shows acetabular dysplasia on the left, and post operation on the right. She is very satisfied with the PAO on the right one year before, so we recommend PAO for the left hip dysplasia again. The key point of PAO includes 4 cuts: ischial cut, pubic cut, acetabular roof cut, and quadrilateral bone cut, and the four cuts should be accomplished accurately. Then the acetabular fragment should be turned to ideal position with the lateral CE angle (LCE) > 25°, the Tönnis acetabular angle 0°, the anterior CE angle (ACE) > 20°, good congruence joint space, and with the hip center medialized slightly. At lastly the acetabular fragment is fixed with proper nails and instruments. The patient is very happy to the surgery with no hip pain, with normal gait, ROM, and Harris hip scores (HHS). In summary, PAO is a relative new and efficient procedure for adult hip dysplasia, requiring accurate techniques. Cadaveric practice and familiar with the local anatomy can help the surgeon overcome the learning curve quickly. © 2015 Chinese Orthopaedic Association and Wiley Publishing Asia Pty Ltd.

  13. Acetabular Wall Indices Help to Distinguish Acetabular Coverage in Asymptomatic Adults With Varying Morphologies.

    PubMed

    Anderson, Lucas A; Anderson, Mike B; Erickson, Jill A; Chrastil, Jesse; Peters, Christopher L

    2017-04-01

    The anterior wall index (AWI) and posterior wall index (PWI) have been proposed to quantify anterior and posterior acetabular coverage using AP pelvic radiographs. However, these indices have only been reported in symptomatic patients with apparent pathomorphologies (dysplasia, overcoverage, and retroversion) undergoing osteochondroplasty or reorientation osteotomy. (1) What are the ranges for AWI and PWI from measurements obtained on AP pelvic radiographs of asymptomatic senior athletes with well-functioning hips? (2) Is there a difference between the AWI and PWI in asymptomatic athletes with acetabular morphology consistent with acetabular dysplasia, overcoverage, and retroversion when compared with asymptomatic hips that do not meet the radiographic definitions for those morphologies (controls)? Five hundred five athletes (998 asymptomatic native hips) were independently evaluated by two readers on AP pelvic radiographs for AWI and the PWI after excluding hips with prior surgery, inadequate radiographs, or poor function (modified Harris hip score < 80). Hips with a lateral center-edge angle (LCEA) ≥ 20° and ≤ 38° and without acetabular retroversion, based on a positive crossover sign, were used as controls. Hips were categorized as developmental dysplasia of the hip (DDH; undercoverage) if the LCEA was < 20°. Finally, overcoverage was defined as an LCEA > 38°. The mean age of the athletes was 67 years (range, 50-91 years) and 55% were men. Linear generalized estimating equation regression was used to compare each individual diagnosis (DDH, retroversion, overcoverage) with the controls for both AWI and PWI adjusting for age and sex. The mean AWI in the study population was 0.36 (range, -0.02 to 0.91). The mean PWI was 1.13 (range, 0.12-1.74). The mean AWI and PWI in controls (n = 740) was 0.35 (range, -0.02 to 0.91) and 1.13 (range, 0.64-1.70), respectively. There were 25 (3%) with DDH in whom the mean AWI was 0.26 (range, 0.05-0.5) and the

  14. Navigated percutaneous screw fixation of a periprosthetic acetabular fracture.

    PubMed

    Gras, Florian; Marintschev, Ivan; Klos, Kajetan; Fujak, Albert; Mückley, Thomas; Hofmann, Gunther O

    2010-10-01

    Periprosthetic fractures are severe complications of total hip arthroplasty with increasing incidence. Most fractures are localized around the femoral component of prosthesis, whereas periacetabular fractures are rare and their management is difficult. In most cases, an operative procedure with revision and exchange of the acetabular cup is necessary. The approaches are demanding and an increased risk of complications is reported. We present the case of a female patient with a cementless total hip arthroplasty due to severe arthritis, suffering of an infratectal transverse periprosthetic fracture. After an initial conservative treatment attempt, we performed a minimally invasive screw fixation using navigated 2-dimensional fluoroscopic guidance. In this report, the literature for treatment recommendations is reviewed and the chosen navigation technique discussed. Copyright © 2010. Published by Elsevier Inc.

  15. Early proximal migration of cups is associated with late revision in THA

    PubMed Central

    2012-01-01

    Background and purpose The association between excessive early migration of acetabular cups and late aseptic revision has been scantily reported. We therefore performed 2 parallel systematic reviews and meta-analyses to determine the association between early migration of acetabular cups and late aseptic revision. Methods One review covered early migration data from radiostereometric analysis (RSA) studies, while the other focused on revision rates for aseptic loosening from long-term survival studies. Thresholds for acceptable and unacceptable migration were classified according the Swedish Hip Arthroplasty Register and the Australian National Joint Replacement Registry: < 5% revision at 10 years. Results Following an elaborate literature search, 26 studies (involving 700 cups) were included in the RSA review and 49 studies (involving 38,013 cups) were included in the survival review. For every mm increase in 2-year proximal migration, there was a 10% increase in revision rate, which remained after correction for age, sex, diagnosis, hospital type, continent, and study quality. Consequently, proximal migration of up to 0.2 mm was considered acceptable and proximal migration of 1.0 mm or more was considered unacceptable. Cups with proximal migration of between 0.2 and 1.0 mm were considered to be at risk of having revision rates higher than 5% at 10 years. Interpretation There was a clinically relevant association between early migration of acetabular cups and late revision due to loosening. The proposed migration thresholds can be implemented in a phased evidence-based introduction, since they allow early detection of high-risk cups while exposing a small number of patients. PMID:23126575

  16. Clinical and Radiological Results over the Medium Term of Isolated Acetabular Revision

    PubMed Central

    Andreani, Lorenzo; Bonicoli, Enrico; Niccolai, Francesco; Lisanti, Michele

    2014-01-01

    Acetabular cup loosening is associated with pain, reduced function, and instability of the implant. If such event happens while the femoral implant is in a satisfactory position and is well fixed to the bone, isolated acetabular revision surgery is indicated. The aim of this single-center retrospective study was to evaluate the clinical and radiological results over the medium term (12-month follow-up mean 36, max 60) of isolated acetabular revisions surgery using a porous hemispheric revision shell matched with a cemented all-poly cup and large diameter femoral head (>32). 33 patients were enrolled. We collect any relevant data from the clinical board. Routine clinical and radiographic examinations were performed preoperatively; the postoperative follow-up was made at 1, 3, and 6 months and yearly thereafter. At the last available follow-up, we report satisfactory improvement of functional scores in all the patients; 2 patients (6.1%) showed thigh pain and only 4 hips (12.11%) presented mild groin pain; all the femoral components are well fixed and there were no potential or pending rerevisions. With bias due to the follow-up and to the retrospective design of the study, we report clinical, functional, and radiological satisfactory results. PMID:25610894

  17. A mathematical method for precisely calculating the radiographic angles of the cup after total hip arthroplasty.

    PubMed

    Zhao, Jing-Xin; Su, Xiu-Yun; Xiao, Ruo-Xiu; Zhao, Zhe; Zhang, Li-Hai; Zhang, Li-Cheng; Tang, Pei-Fu

    2016-11-01

    We established a mathematical method to precisely calculate the radiographic anteversion (RA) and radiographic inclination (RI) angles of the acetabular cup based on anterior-posterior (AP) pelvic radiographs after total hip arthroplasty. Using Mathematica software, a mathematical model for an oblique cone was established to simulate how AP pelvic radiographs are obtained and to address the relationship between the two-dimensional and three-dimensional geometry of the opening circle of the cup. In this model, the vertex was the X-ray beam source, and the generatrix was the ellipse in radiographs projected from the opening circle of the acetabular cup. Using this model, we established a series of mathematical formulas to reveal the differences between the true RA and RI cup angles and the measurements results achieved using traditional methods and AP pelvic radiographs and to precisely calculate the RA and RI cup angles based on post-operative AP pelvic radiographs. Statistical analysis indicated that traditional methods should be used with caution if traditional measurements methods are used to calculate the RA and RI cup angles with AP pelvic radiograph. The entire calculation process could be performed by an orthopedic surgeon with mathematical knowledge of basic matrix and vector equations. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  18. Influence of the sagittal balance of the spine on the anterior pelvic plane and on the acetabular orientation.

    PubMed

    Legaye, Jean

    2009-12-01

    The Anterior Pelvic Plane (APP), defined by the anterior superior iliac spines and the pubic tubercle, was commonly used as reference for positioning and postoperative evaluation of the orientation of the acetabular cup in total hip arthroplasty. APP was assumed to be vertical, but was not observed always so, mostly because of associated spinal diseases inducing perturbations in the harmony of the sagittal balance of the pelvi-spinal unit. Consequently a sagittal rotation of the pelvis occurs, and so a tilt of the APP which alters directly the orientation of the cup in upright position. An analysis of the APP tilt related to the sagittal balance of the spine was provided and its implication on the cup orientation. It appeared essential for an individual adjustment of the cup positioning to avoid a functional mal-position which can lead to an increased risk of dislocation and impingement.

  19. Skeletal Dysplasias

    PubMed Central

    Krakow, Deborah

    2015-01-01

    Synoposis The skeletal dysplasias are a group of more than 450 heritable disorders of bone. They frequently present in the newborn period with disproportion, radiographic abnormalities, and occasionally other organ system abnormalities. For improved clinical care it is important to determine a precise diagnosis to aid in management, familial recurrence and identify those disorders highly associated with mortality. Long-term management of these disorders is predicated on an understanding of the associated skeletal system abnormalities and these children are best served by a team approach to health care surveillance. PMID:26042906

  20. Effect of acetabular labrum tears on hip stability and labral strain in a joint compression model.

    PubMed

    Smith, Matthew V; Panchal, Hemang B; Ruberte Thiele, Ramon A; Sekiya, Jon K

    2011-07-01

    Acetabular labrum tears are now commonly diagnosed in young and active patients. Because the role of the acetabular labrum is incompletely understood, it is critical to determine how these tears affect native hip biomechanics. Radial and circumferential labral tears significantly decrease hip stability and significantly alter strain patterns in the anterior and anterior-superior acetabular labrum. Controlled laboratory study. Twenty-two human cadaveric hips without evidence of degeneration or dysplasia were assigned to a circumferential tear (n = 11) and a radial tear (n = 11) group. The hips were tested in a neutral position with an average compressive force of 25 N. In the circumferential tear group, the labral states were intact; 1-, 2-, and 3-cm circumferential tears; a 3-cm partial labrectomy; and a full labrectomy. In the radial tear group, the labral states were intact; a radial tear; a 1-, 2-, and 3-cm partial labrectomy; and a full labrectomy. The effect of labral injury on the stability ratio (peak dislocation force/compressive loads) and labral strain in the anterior and anterior-superior labrum was analyzed using repeated-measures analysis of variance. There was no significant difference in stability ratio after circumferential tears 3 cm or less in size compared with the intact labral state. Strain in the anterior and anterior-superior labrum was either unchanged or increased after circumferential labral tear. There was no significant difference in stability ratio after a radial tear or a 1-cm partial labrectomy compared with the intact labral state. A 2-cm partial labrectomy significantly decreased the stability ratio. Anterior and anterior-superior labral strain significantly decreased after a radial tear. Under the influence of joint compression in a neutral hip position, the acetabular labrum continues to resist femoral head dislocation despite detachment from the acetabular rim. A radial tear in the acetabular labrum decreases adjacent labral

  1. Are custom triflange acetabular components effective for reconstruction of catastrophic bone loss?

    PubMed

    Berasi, Carl C; Berend, Keith R; Adams, Joanne B; Ruh, Erin L; Lombardi, Adolph V

    2015-02-01

    Although the introduction of ultraporous metals in the forms of acetabular components and augments has increased the orthopaedic surgeon's ability to reconstruct severely compromised acetabuli, there remain some that cannot be managed readily using cups, augments, or cages. In such situations, allograft-prosthetic composites or custom acetabular components may be called for. However, few studies have reported on the results of these components. The purposes of this study were to determine the (1) frequency of repeat revision, (2) complications and radiographic findings, and (3) Harris hip scores in patients who underwent complex acetabular revision surgery with custom acetabular components. Between August 2003 and February 2012, 26 patients (28 hips) have undergone acetabular reconstruction with custom triflange components. During this time, the general indications for using these implants included (1) failed prior salvage reconstruction with cage or porous metal construct augments, (2) large contained defects with possible discontinuity, (3) known pelvic discontinuity, and (4) complex multiply surgically treated hips with insufficient bone stock to reconstruct using other means. This approach was used in a cohort of patients with Paprosky Type 3B acetabular defects, which represented 3% (30 of 955) of the acetabular revisions we performed during the study period. Minimum followup was 2 years (mean, 57 months; range, 28-108 months). Seven patients (eight hips) died during the study period, and three (11%) of these patients (four hips; 14%) were lost to followup before 2 years, leaving 23 patients (24 hips) with minimum 2-year followup. Sixteen patients were women. The mean age of the patients was 67 years (range, 47-85 years) and mean BMI was 28 kg/m2 (range, 23-39 kg/m2). Revisions and complications were identified by chart review; hip scores were registered in our institution's longitudinal database. Pre- and postoperative radiographs were analyzed by the patient

  2. 3D non-linear analysis of the acetabular construct following impaction grafting.

    PubMed

    Phillips, A T M; Pankaj, P; Howie, C R; Usmani, A S; Simpson, A H R W

    2006-06-01

    The study investigates the short-term behaviour of the acetabular construct following revision hip arthroplasty, carried out using the Slooff-Ling impaction grafting technique; using 3D finite element analyses. An elasto-plastic material model is used to describe the constitutive behaviour of morsellised cortico-cancellous bone (MCB) graft, since it has been shown that MCB undergoes significant plastic deformation under normal physiological loads. Based on previous experimental studies carried out by the authors and others, MCB is modelled using non-linear elasticity and Drucker Prager Cap (DPC) plasticity. Loading associated with walking, sitting down, and standing up is applied to the acetabular cup through a femoral head using smooth sliding surfaces. The analyses yield distinctive patterns of migration and rotation due to different activities. These are found to be similar to those observed in the clinical setting.

  3. The effect of under-reaming on the cup/bone interface of a press fit hip replacement.

    PubMed

    Zivkovic, I; Gonzalez, M; Amirouche, F

    2010-04-01

    This paper explores the effect of under-reaming on micromotion at the cup/bone interface of a press-fit acetabular cup. A cadaver experiment was performed on 11 acetabuli implanted with a cementless acetabular cup. The loading profile simulated hip impingement at the extremes of motion and subluxation relocation of the hip joint. Micromotion of each cup was measured in a custom made jig with linear variable differential transducers. A CAT scan and DEXA scan of the acetabulum and femoral head respectively were used to construct a three-dimensional patient specific finite element model of the hemi-pelvis. The model predicted cup micromotion under loading conditions and stresses in the acetabulum as a result of cup insertion. Micromotion was then calculated as a function of variable bone density and variable degree of underreaming. Simulated cup insertion with under-reaming of 2 mm or more approached or exceeded the yield strength of bone in acetabula with reduced bone mass density.

  4. Does Salter innominate osteotomy predispose the patient to acetabular retroversion in adulthood?

    PubMed

    Kobayashi, Daisuke; Satsuma, Shinichi; Kinugasa, Maki; Kuroda, Ryosuke; Kurosaka, Masahiro

    2015-05-01

    Salter innominate osteotomy has been identified as an effective additional surgery for the dysplastic hip. However, because in this procedure, the distal segment of the pelvis is displaced laterally and anteriorly, it may predispose the patient to acetabular retroversion. The degree to which this may be the case, however, remains incompletely characterized. We asked, in a group of pediatric patients with acetabular dysplasia who underwent Salter osteotomy, whether the operated hip developed (1) acetabular retroversion compared with contralateral unaffected hips; (2) radiographic evidence of osteoarthritis; or (3) worse functional scores. (4) In addition, we asked whether femoral head deformity resulting from aseptic necrosis was a risk factor for acetabular retroversion. Between 1971 and 2001, we performed 213 Salter innominate osteotomies for unilateral pediatric dysplasia, of which 99 hips (47%) in 99 patients were available for review at a mean of 16 years after surgery (range, 12-25 years). Average patient age at surgery was 4 years (range, 2-9 years) and the average age at the most recent followup was 21 years (range, 18-29 years). Acetabular retroversion was diagnosed based on the presence of a positive crossover sign and prominence of the ischial spine sign at the final visit. The center-edge angle, acetabular angle of Sharp, and acetabular index were measured at preoperative and final visits. Contralateral unaffected hips were used as controls, and statistical comparison was made in each patient. Clinical findings, including Harris hip score (HHS) and the anterior impingement sign, were recorded at the final visit. Patients were no more likely to have a positive crossover sign in the surgically treated hips (20 of 99 hips [20%]) than in the contralateral control hips (17 of 99 hips [17%]; p = 0584). In addition, the percentage of positive prominence of the ischial spine sign was not different between treated hips (22 of 99 hips [22%]) and contralateral hips

  5. 10-year results of the uncemented Allofit press-fit cup in young patients

    PubMed Central

    Streit, Marcus R; Weiss, Stefan; Andreas, Franziska; Bruckner, Thomas; Walker, Tilman; Kretzer, J Philippe; Ewerbeck, Volker; Merle, Christian

    2014-01-01

    Background and purpose Uncemented acetabular components in primary total hip arthroplasty (THA) are commonly used today, but few studies have evaluated their survival into the second decade in young and active patients. We report on a minimum 10-year follow-up of an uncemented press-fit acetabular component that is still in clinical use. Methods We examined the clinical and radiographic results of our first 121 consecutive cementless THAs using a cementless, grit-blasted, non-porous, titanium alloy press-fit cup (Allofit; Zimmer Inc., Warsaw, IN) without additional screw fixation in 116 patients. Mean age at surgery was 51 (21–60) years. Mean time of follow-up evaluation was 11 (10–12) years. Results At final follow-up, 8 patients had died (8 hips), and 1 patient (1 hip) was lost to follow-up. 3 hips in 3 patients had undergone acetabular revision, 2 for deep infection and 1 for aseptic acetabular loosening. There were no impending revisions at the most recent follow-up. We did not detect periacetabular osteolysis or loosening on plain radiographs in those hips that were evaluated radiographically (n = 90; 83% of the hips available at a minimum of 10 years). Kaplan-Meier survival analysis using revision of the acetabular component for any reason (including isolated inlay revisions) as endpoint estimated the 11-year survival rate at 98% (95% CI: 92–99). Interpretation Uncemented acetabular fixation using the Allofit press-fit cup without additional screws was excellent into early in the second decade in this young and active patient cohort. The rate of complications related to the liner and to osteolysis was low. PMID:24875058

  6. [Fibrous dysplasia].

    PubMed

    Rödl, R; Götze, C

    2008-01-01

    Fibrous dysplasia is a tumorlike, benign lesion, caused by sporadic mutation during early embryogenesis. The skeletal involvement becomes increasingly visible during growth. The number and extent of dysplastic lesions increase until the age of 15. The polyostotic form is often associated with endocrine dysfunction, which should be diagnosed and treated early. Malignant transformation of fibrous dysplastic lesions is less than 1%; therefore, treatment or resection of the lesion itself is not necessary. The progress of the lesions during growth can lead to pain, fractures, and deformities. Bisphosphonates are effective for pain relief, but have no assured effect on the natural history of the disease. Fracture healing is not compromised by the disease. Conservative treatment with casts is therefore effective, especially for the upper limbs. The surgical approach with deformity correction and stabilization remains challenging particularly with regard to the proximal femur. Intramedullary devices should be preferred to plates, if possible.

  7. Dual mobility cups in total hip arthroplasty

    PubMed Central

    De Martino, Ivan; Triantafyllopoulos, Georgios Konstantinos; Sculco, Peter Keyes; Sculco, Thomas Peter

    2014-01-01

    Total hip arthroplasty (THA) is considered one of the most successful surgical procedures in orthopaedics. With the increase in the number of THAs performed in the world in the next decades, reducing or preventing medical and mechanical complications such as post-operative THA instability will be of paramount importance, particularly in an emerging health care environment based on quality control and patient outcome. Dual mobility acetabular component (also known as unconstrained tripolar implant) was introduced in France at the end of the 1970s as an alternative to standard sockets, to reduce the risk of THA dislocation in patients undergoing primary THA in France. Dual mobility cups have recently gained wider attention in the United States as an alternative option in the prevention and treatment of instability in both primary and revision THA and offer the benefit of increased stability without compromising clinical outcomes and implant longevity. In this article, we review the use of dual mobility cup in total hip arthroplasty in terms of its history, biomechanics, outcomes and complications based on more than 20 years of medical literature. PMID:25035820

  8. Cementless RM Pressfit Cup: a clinical and radiological study of 91 cases with at least four years follow-up.

    PubMed

    Lafon, L; Moubarak, H; Druon, J; Rosset, P

    2014-06-01

    Cementless metal-back acetabular cups have good long-term results, but some problems have appeared due to the shell's stiffness, modularity and required bearing surfaces. The RM Pressfit Cup is a single-piece polyethylene cementless acetabular cup that is covered by a thin layer of titanium. This allows for bone integration without limitations related to the stiffness of a metal-back shell. There is very little published information about this new, innovative implant design. The purpose of this study was to evaluate the clinical and radiological results from a continuous series of 91 cups (85 patients) with a follow-up of at least 4 years. No patients were lost to follow-up. The Harris Hip Score (HHS) was used to assess the clinical outcome. To assess the radiological outcomes, digital X-rays were used to evaluate the cup position and integration; wear was measured using Livermore's technique. The clinical results were excellent: the mean HHS was 94 and 82% of cases had good or excellent scores. Three of the cups had to be revised because of dislocation brought on by incorrect positioning. X-rays revealed that three implants had shifted during the first 6 weeks, but had stabilized afterwards. Bone integration on X-rays was satisfactory in all cases with no signs of osteolysis. The configuration of the bone trabeculae showed that loads between the implant and peri-acetabular cancellous bone were evenly distributed. The wear of the polyethylene cup-ceramic head bearing was 0.07 mm/year. The results of this series are consistent with recent published studies with the RM Pressfit Cup. IV. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  9. Clinical and radiological outcome of the cemented Contemporary acetabular component in patients < 50 years of age.

    PubMed

    Schmitz, M W J L; Timmer, C; Rijnen, W H C; Gardeniers, J W M; Schreurs, B W

    2013-12-01

    Despite the worldwide usage of the cemented Contemporary acetabular component (Stryker), no published data are available regarding its use in patients aged < 50 years. We undertook a mid- to long-term follow-up study, including all consecutive patients aged < 50 years who underwent a primary total hip replacement using the Contemporary acetabular component with the Exeter cemented stem between January 1999 and January 2006. There were 152 hips in 126 patients, 61 men and 65 women, mean age at surgery 37.6 years (16 to 49 yrs). One patient was lost to follow-up. Mean clinical follow-up of all implants was 7.6 years (0.9 to 12.0). All clinical questionnaire scores, including Harris hip score, Oxford hip score and several visual analogue scales, were found to have improved. The eight year survivorship of all acetabular components for the endpoints revision for any reason or revision for aseptic loosening was 94.4% (95% confidence interval (CI) 89.2 to 97.2) and 96.4% (95% CI 91.6 to 98.5), respectively. Radiological follow-up was complete for 146 implants. The eight year survival for the endpoint radiological loosening was 93.1% (95% CI 86.2 to 96.6). Three surviving implants were considered radiologically loose but were asymptomatic. The presence of acetabular osteolysis (n = 17, 11.8%) and radiolucent lines (n = 20, 13.9%) in the 144 surviving cups indicates a need for continued observation in the second decade of follow-up in order to observe their influence on long-term survival. The clinical and radiological data resulting in a ten-year survival rate > 90% in young patients support the use of the Contemporary acetabular component in this specific patient group.

  10. The use of a constrained acetabular component to treat instability after total hip arthroplasty.

    PubMed

    Shrader, M Wade; Parvizi, Javad; Lewallen, David G

    2003-11-01

    Recurrent dislocation after total hip arthroplasty is a disabling complication that can be difficult to treat and may not be amenable to nonoperative management. The purpose of the present study was to evaluate the clinical and radiographic outcome associated with the use of a constrained acetabular component as a salvage treatment for instability after hip arthroplasty. We retrospectively reviewed the clinical and radiographic outcome of 110 arthroplasties, in 109 patients, that had been performed with use of a single design of constrained acetabular component. In seventy-nine hips the constrained component was implanted for the treatment of recurrent instability, and in thirty-one hips it was implanted because of absent or grossly deficient soft-tissue attachments that were believed to be associated with a high risk for subsequent instability. The constrained acetabular device eliminated or prevented hip instability in all patients except two, who continued to have sensations of subluxation. The mean Harris hip score improved significantly, from 62.7 points preoperatively to 76.4 points at the time of the latest follow-up (p < 0.0001). There were no instances of dislocation or disassembly of the hip components. Radiographic analysis revealed radiolucent lines around the cup in fifteen hips (14%). There was a total of nine revisions: six for deep infection, two for acetabular component loosening, and one for a periprosthetic fracture of the femur. A constrained acetabular component reliably restores and maintains hip stability in patients with recalcitrant recurrent instability and can dependably prevent dislocation in those who are at high risk because of absent or deficient soft tissues about the hip. However, because of the early appearance of radiolucent lines around some components and concerns about long-term fixation, the use of these devices should be reserved for situations in which other methods are inadequate or have already failed.

  11. Genetics Home Reference: boomerang dysplasia

    MedlinePlus

    ... Dysplasia MalaCards: boomerang dysplasia Orphanet: Boomerang dysplasia Patient Support and Advocacy Resources (3 links) International Skeletal Dysplasia Registry, UCLA March of Dimes: Loss and Grief The Compassionate Friends GeneReviews (1 link) FLNB-Related ...

  12. Reconstruction of the Acetabulum in Developmental Dysplasia of the Hip in total hip replacement

    PubMed Central

    Sakellariou, Vasileios I.; Christodoulou, Michael; Sasalos, Gregory; Babis, George C.

    2014-01-01

    Developmental dysplasia of the hip (DDH) or congenital hip dysplasia (CDH) is the most prevalent developmental childhood hip disorder. It includes a wide spectrum of hip abnormalities ranging from dysplasia to subluxation and complete dislocation of the hip joint. The natural history of neglected DDH in adults is highly variable. The mean age of onset of symptoms is 34.5 years for dysplastic DDH, 32.5 years for low dislocation, 31.2 years for high dislocation with a false acetabulum, and 46.4 years for high dislocation without a false acetabulum. Thorough understanding of the bony and soft tissue deformities induced by dysplasia is crucial for the success of total hip arthroplasty. It is important to evaluate the existing acetabular deformity three-dimensionally, and customize the correction in accordance with the quantity and location of ace tabular deficiencies. Acetabular reconstruction in patients with DDH is challenging. Interpretation of published data is difficult and should be done with caution because most series include patients with different types of hip disease. In general, the complication rate associated with THA is higher in patients with hip dysplasia than it is in patients with osteoarthritis. Overall, clinical and functional outcomes following THA in patients hip dysplasia (DDH) differ from those treated for primary hip osteoarthritis, possibly due to the lower age and level of activity. Although function scores decline with age, the scores for pain and range of motion presented with a statistically significant improvement in the long-term. PMID:25386570

  13. Bleeding and cupping.

    PubMed Central

    Turk, J. L.; Allen, E.

    1983-01-01

    Bleeding and cupping have been used in medicine since ancient times in the treatment of fevers and local inflammatory disorders. Local bleeding, by 'wet cupping', was effected by a scarificator or by leeches. John Hunter recommended venesection in moderation but preferred leeches for local bleeding. Bleeding as an accepted therapeutic practice went out of vogue in the middle of the nineteenth century as a result of the introduction of modern scientific methods. Dry cupping and the use of leeches, as counter irritants, persisted until the middle of this century. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:6338802

  14. Comparison of acetabular anterior coverage after Salter osteotomy and Pemberton acetabuloplasty: a long-term followup.

    PubMed

    Wang, Cheng-Wei; Wu, Kuan-Wen; Wang, Ting-Ming; Huang, Shier-Chieg; Kuo, Ken N

    2014-03-01

    The Salter osteotomy and Pemberton acetabuloplasty are common procedures for a deficient acetabulum in patients with developmental dysplasia of the hip. However, the degree of increasing retroversion and anterior acetabular coverage of these two procedures remains unanswered. The purpose of this study is to show the change in anterior coverage and relevant parameters in measuring pain and function among patients who have undergone either a Salter osteotomy or Pemberton acetabuloplasty. Forty-two patients who underwent either a Salter or Pemberton procedure at one institution between January 1981 and December 2000 and were available for followup at least 10 years later (mean, 18 years; range, 12-28 years) were evaluated retrospectively. This represented 12% of the Salter and Pemberton procedures performed in patients between 12 and 36 months old at our institution during the study period. We measured vertical-center-anterior margin angle, anterior acetabular head index, and weightbearing zone acetabular index, and we made comparisons using the radiographic parameter ratio (the division of each radiographic measurement of the operative side by that of the nonoperated side). All patients completed SF-36 and Harris hip score questionnaires at followup. In the Salter group, there were no differences in vertical-center-anterior margin angle, anterior acetabular head index, or weightbearing zone acetabular index. In the Pemberton group, there was no difference in vertical-center-anterior margin angle or anterior acetabular head index, but the weightbearing zone acetabular index decreased, suggesting increased anterior acetabular coverage (surgically treated side, 6 [95% CI, 4.84, 7.16]; nonoperated side, 12 [95% CI, 10.07, 13.39]; p < 0.001). Compared with that in the Salter group, the weightbearing zone acetabular index ratio was smaller in the Pemberton group, which means more acquired anterior coverage after a Pemberton acetabuloplasty (Salter procedure, 0.94 [95

  15. Change in acetabular version after lumbar pedicle subtraction osteotomy to correct post-operative flat back: EOS® measurements of 38 acetabula.

    PubMed

    Masquefa, T; Verdier, N; Gille, O; Boissière, L; Obeid, I; Maillot, C; Tournier, C; Fabre, T

    2015-10-01

    Abnormalities in acetabular orientation can promote the development of hip osteoarthritis, femoro-acetabular impingement, or even acetabular cup malposition. The objective of the present study was to determine whether pedicle substraction osteotomy (PSO) to correct sagittal spinal imbalance affected acetabular orientation. PSO performed to correct sagittal spinal imbalance affects acetabular orientation by changing the pelvic parameters. This was a descriptive study in which two observers measured the acetabular parameters on both sides in 19 patients (38 acetabula) before and after PSO for post-operative flat-back syndrome. Mean time from PSO to post-operative measurements was 19months. Measurements were taken twice at a 2-week interval, on standing images obtained using the EOS(®) imaging system and sterEOS(®) software to obtain 3D reconstructions of synchronised 2D images. Acetabular anteversion and inclination were measured relative to the vertical plane. Mean pre-PSO and post-PSO values were compared using the paired t-test, and P values lower than 0.05 were considered significant. To assess inter-observer and intra-observer reproducibility, we computed the intra-class correlation coefficients (ICCs). The measurements showed significant acetabular retroversion after PSO, of 7.6° on the right and 6.5° on the left (P<0.001). Acetabular inclination diminished significantly, by 4.5° on the right and 2.5° on the left (P<0.01). Inclination of the anterior pelvic plane decreased by 8.4° (P<0.01). Pelvic incidence was unchanged, whereas sacral slope increased by 10.5° (P<0.001) and pelvic tilt decreased by 10.9° (P<0.001). The ICC was 0.98 for both inter-observer and intra-observer reproducibility. Changing the sagittal spinal alignment modifies both the pelvic and the acetabular parameters. PSO significantly increases sacral slope, thus inducing anterior pelvic tilt with significant acetabular retroversion. The measurements obtained using sterEOS(®) showed

  16. Outcomes of polyethylene liner cementation into a fixed metal acetabular shell with minimum follow-up of 7 years.

    PubMed

    Park, Myung-Sik; Yoon, Sun-Jung; Lee, Ju Rang

    2015-01-01

    Cementation of a polyethylene liner into the well-fixed shell is a convenient option for revision total hip arthroplasty. We retrospectively reviewed 45 patients who had liner cementation to investigate the risk factors which gave rise to major complications and reoperation. Patients were observed for a minimum of 7 years (range 7.8-14 years). Relevant risk factors (age, BMI, surgical approach, previous cup size and position, types of coated surface) were assessed with Cox regression analysis. The mean Harris Hip Score was improved from 62.5 (range 57-68) preoperatively to 87.1 (range 70-97). A total of 7 hips (15.5%) had acetabular component loosening that was treated with reoperation. Prevalence of acetabular component loosening was statistically significantly higher in hydroxyapatite-coated group (5 of 13) than in the Ti-coated group (2 of 32, p = 0.015). All recurrent dislocations occurred in patients treated with a posterior approach. Diameter of the previous metal shell of below 54 mm showed a lower 10-year survival rate than those greater than 54 mm in diameter. PE liner cementation in stable metal cup is a useful alternative option for carefully selected patients. Pre-existing HA-coated cups as well as small sized cups were indicative of poor outcomes.

  17. Oculodentodigital dysplasia

    PubMed Central

    Doshi, Dharmil C; Limdi, Purvi K; Parekh, Nilesh V; Gohil, Neepa R

    2016-01-01

    Oculodentodigital dysplasia is a rare, autosomal dominant disorder with high penetrance and variable expressivity, caused by mutations in the connexin 43 or gap junction protein alpha-1 gene. It has been diagnosed in fewer than 300 people worldwide with an incidence of around 1 in 10 million. It affects many parts of the body, particularly eyes (oculo), teeth (dento), and fingers and/or toes (digital). The common clinical features include facial dysmorphism with thin nose, microphthalmia, syndactyly, tooth anomalies such as enamel hypoplasia, anodontia, microdontia, early tooth loss and conductive deafness. Other less common features are abnormalities of the skin and its appendages, such as brittle nails, sparse hair, and neurological abnormalities. To prevent this syndrome from being overlooked, awareness of possible symptoms is necessary. Early recognition can prevent blindness, dental problems and learning disabilities. Described here is the case of a 21-year-old male who presented to the ophthalmology outpatient department with a complaint of bilateral progressive loss of vision since childhood. PMID:27146935

  18. Activity Level and Severity of Dysplasia Predict Age at Bernese Periacetabular Osteotomy for Symptomatic Hip Dysplasia.

    PubMed

    Matheney, Travis; Zaltz, Ira; Kim, Young-Jo; Schoenecker, Perry; Millis, Michael; Podeszwa, David; Zurakowski, David; Beaulé, Paul; Clohisy, John

    2016-04-20

    The age when patients present for treatment of symptomatic developmental dysplasia of the hip with periacetabular osteotomy (PAO) varies widely. Modifiable factors influencing age at surgery include preexisting activity level and body mass index (BMI). The severity of the hip dysplasia has also been implicated as a factor influencing the age at arthritis onset. The purpose of this study was to determine whether activity level, BMI, and severity of dysplasia are independent predictors of age of presentation for PAO. A retrospective, institutional review board-approved review of prospectively collected data from a multicenter study group identified 708 PAOs performed for developmental dysplasia of the hip. Demographic factors that were considered in the analysis included age at surgery, BMI, history of hip disorder or treatment, and duration of symptoms. The severity of the developmental dysplasia of the hip was assessed by radiographic measurement of the lateral and anterior center-edge angles and acetabular inclination. Activity level was assessed with the University of California, Los Angeles (UCLA) activity score. Spearman correlations and t tests were used for univariable analysis. Multivariable regression analysis using generalized estimating equations was applied to determine independent predictors of age at PAO. Univariable analysis indicated that age at presentation for treatment of PAO correlated with the lateral and anterior center-edge angles (p < 0.001), UCLA score (p < 0.001), and BMI (p = 0.04). Since the lateral and anterior center-edge angles were similarly correlated (Spearman rho = 0.61, p < 0.001), the lateral center-edge angle alone was used to classify the severity of the developmental dysplasia of the hip. Multivariable linear regression confirmed that a high UCLA score and severe hip dysplasia were independent predictors of age at PAO (p < 0.001). A high activity level and severe dysplasia lead to the development of symptoms and presentation

  19. World Cup Final

    NASA Image and Video Library

    2006-07-05

    On July 9, hundreds of millions of fans worldwide were glued to their television sets watching the final match of the 2006 FIFA World Cup, played in Berlin Olympic stadium Olympiastadion. This image was acquired by NASA Terra spacecraft.

  20. Effects of hydroxyapatite coating of cups used in hip revision arthroplasty

    PubMed Central

    2012-01-01

    Background and purpose Coating of acetabular revision implants with hydroxyapatite (HA) has been proposed to improve ingrowth and stability. We investigated whether HA coating of revision cups can reduce the risk of any subsequent re-revision. Methods We studied uncemented cups either with or without HA coating that were used at a primary acetabular revision and registered in the Swedish Hip Arthroplasty Register (SHAR). 2 such cup designs were identified: Harris-Galante and Trilogy, both available either with or without HA coating. These cups had been used as revision components in 1,780 revisions of total hip arthroplasties (THA) between 1986 and 2009. A Cox proportional hazards model including the type of coating, age at index revision, sex, cause of cup revision, cup design, the use of bone graft at the revision procedure, and the type of cup fixation at primary THA were used to calculate adjusted risk ratios (RRs with 95% CI) for re-revision for any reason or due to aseptic loosening. Results 71% of the cups were coated with HA and 29% were uncoated. At a mean follow-up time of 6.9 (0–24) years, 159 (9%) of all 1,780 cups had been re-revised, mostly due to aseptic loosening (5%), dislocation (2%), or deep infection (1%). HA coating had no significant influence on the risk of re-revision of the cup for any reason (RR = 1.4, CI: 0.9–2.0) or due to aseptic loosening (RR = 1.1, 0.6–1.9). In contrast, HA coating was found to be a risk factor for isolated liner re-revision for any reason (RR = 1.8, CI: 1.01–3.3). Age below 60 years at the index cup revision, dislocation as the cause of the index cup revision, uncemented cup fixation at primary THA, and use of the Harris-Galante cup also increased the risk of re-revision of the cup. In separate analyses in which isolated liner revisions were excluded, bone grafting was found to be a risk factor for re-revision of the metal shell due to aseptic loosening (RR = 2.1, CI: 1.05–4.2). Interpretation We found no

  1. Safe surgical technique for associated acetabular fractures

    PubMed Central

    2013-01-01

    Associated acetabular fractures are challenging injuries to manage. The complex surgical approaches and the technical difficulty in achieving anatomical reduction imply that the learning curve to achieve high-quality care of patients with such challenging injuries is extremely steep. This first article in the Journal’s “Safe Surgical Technique” section presents the standard surgical care, in conjunction with intraoperative tips and tricks, for the safe management of all subgroups of associated acetabular fractures. PMID:23414782

  2. The Morscher Press-Fit Acetabular Component: An Independent Long-Term Review at 18-22 Years.

    PubMed

    Gwynne-Jones, David P; Lash, Heath W R; James, Andrew W; Iosua, Ella E; Matheson, John A

    2017-08-01

    There are relatively few 20-year results of uncemented acetabular components, and most of these are modular designs. This study reports the 20-year results of a monoblock press-fit acetabular component. A total of 122 total hip arthroplasties (111 patients) using the Morscher cup were reviewed at a mean of 19.7 years. The average age at implantation was 57.3 years (range, 36-74 years), and 81 (66%) were men. Twenty-two patients (25 hips) had died. Seven hips were revised, including 5 acetabular revisions. Six patients (6 hips) declined to participate but were known not to have been revised. The mean Oxford hip score was 41.1 (range, 22-48), and the mean reduced Western Ontario and McMaster Universities Osteoarthritis Index score was 5.7/48 (range, 0-24). Eccentric wear was seen in 13 (15.7%) and major osteolysis in 14 (17%) of 82 surviving hips with radiographs. The all-cause revision rate was 0.32 per 100 observed component years (95% confidence interval [CI], 0.13-0.66). The 20-year Kaplan-Meier survival was 93.4% (CI, 86.6-96.8) for all-cause revisions, 95.5% (CI, 89.4-98.1) for any acetabular revision, and 97.1% (CI, 91.2-99.1) for acetabular aseptic loosening, wear, or osteolysis. The Morscher acetabular component has continued to perform well at 20 years despite using conventional polyethylene with results that match or surpass other cementless acetabulae. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Orthopedics management of acromicric dysplasia: follow up of nine patients.

    PubMed

    Klein, Céline; Le Goff, Carine; Topouchian, Vicken; Odent, Sylvie; Violas, Philippe; Glorion, Christophe; Cormier-Daire, Valérie

    2014-02-01

    Acromicric dysplasia (AD) is an autosomal dominant disorder characterized by short stature, short extremities, stiff joint and skeleton features including brachymetacarpia, cone-shaped epiphyses, internal notch of the femoral head, and delayed bone age. Recently, we identified fibrillin 1 (FBN1) as the disease gene of AD. The aim of our study was to further describe the long-term follow up of AD patients with an emphasis on orthopedic management. Nine patients with FBN1 mutations were included in the study ranging in age from 5.5 to 64 years. For all, detailed clinical and radiological data were available. Birth parameters were always normal and patients progressively developed short stature <-3 SD. Carpal tunnel syndrome was observed in four patients. We found discrepancy between the carpal bone age and the radius and ulna epiphysis bone ages, a variable severity of hip dysplasia with acetabular dysplasia, epiphyseal and metaphyseal femoral dysplasia resembling Legg-Perthes-Calvé disease and variable pelvic anteversion and hyperlordosis. Orthopedic surgery was required in two patients for hip dysplasia, in one for limb lengthening and in three for carpal tunnel syndrome. Our observations expand the AD phenotype and emphasize the importance of regular orthopedic survey. © 2013 Wiley Periodicals, Inc.

  4. Deformation of the Durom Acetabular Component and Its Impact on Tribology in a Cadaveric Model—A Simulator Study

    PubMed Central

    Gu, Yanqing; Wang, Qing; Cui, Weiding; Fan, Weimin

    2012-01-01

    Background Recent studies have shown that the acetabular component frequently becomes deformed during press-fit insertion. The aim of this study was to explore the deformation of the Durom cup after implantation and to clarify the impact of deformation on wear and ion release of the Durom large head metal-on-metal (MOM) total hips in simulators. Methods Six Durom cups impacted into reamed acetabula of fresh cadavers were used as the experimental group and another 6 size-paired intact Durom cups constituted the control group. All 12 Durom MOM total hips were put through a 3 million cycle (MC) wear test in simulators. Results The 6 cups in the experimental group were all deformed, with a mean deformation of 41.78±8.86 µm. The average volumetric wear rate in the experimental group and in the control group in the first million cycle was 6.65±0.29 mm3/MC and 0.89±0.04 mm3/MC (t = 48.43, p = 0.000). The ion levels of Cr and Co in the experimental group were also higher than those in the control group before 2.0 MC. However there was no difference in the ion levels between 2.0 and 3.0 MC. Conclusions This finding implies that the non-modular acetabular component of Durom total hip prosthesis is likely to become deformed during press-fit insertion, and that the deformation will result in increased volumetric wear and increased ion release. Clinical Relevance This study was determined to explore the deformation of the Durom cup after implantation and to clarify the impact of deformation on wear and ion release of the prosthesis. Deformation of the cup after implantation increases the wear of MOM bearings and the resulting ion levels. The clinical use of the Durom large head prosthesis should be with great care. PMID:23144694

  5. The use of a constrained cementless acetabular component for instability in total hip replacement.

    PubMed

    Rady, Ahmad Emad; Asal, Mohammed Kamal; Bassiony, Ayman Abdelaziz

    2010-01-01

    Recurrent dislocation after total hip arthroplasty is a disabling complication that can be difficult to treat. We evaluated the early clinical and radiographic outcome associated with the use of a constrained acetabular component for instability in total hip arthroplasty. Fifteen patients underwent either primary or revision total hip arthroplasty with a cementless constrained acetabular component for different indications. The mean patient age at surgery was 57.4 years and the mean clinical and radiological follow-up period was 26.4 months. Clinical assessment was performed by the Harris hip score and at the latest follow up patients reported outcome using the Oxford hip score questionnaire. All radiographs were evaluated for evidence of loosening. Only one patient experienced redislocation with the constrained prosthesis. The average Harris hip score increased from a preoperative mean of 22 (range, 16 - 36) to a postoperative mean of 85 (range, 66-94). Preoperatively, the mean Oxford Hip Score was 48.6, which decreased to 20.5 at the final examination. All but one of the 15 hips had a well-fixed, stable cup. Femoral component stability with bone ingrowth was achieved in 10 cases. A constrained acetabular component is an effective option for the treatment of hip instability in primary and revision arthroplasty in those at high risk of dislocation. The potential for aseptic loosening requires evaluation by long term studies.

  6. Pseudoachondroplastic Dysplasia

    PubMed Central

    Stevens, Jeff W

    1999-01-01

    Lamellar inclusions of the rough endoplasmic reticulum in growth plate chondrocytes, first identified (1972) in the Department of Orthopaedic Surgery, University of Iowa, has become the cytochemical hallmark for the pseudoachondroplastic dysplasia (PSACH) phenotype, linking an endoplasmic reticulum storage disorder with the osteochondrodysplasia. Since this original observation, great advances have been made, leading to the molecular understanding of this altered longitudinal bone growth anomaly. A PSACH canine model suggested that abatement of cumulative vertical growth of growth plate chondrocytes seen in PSACH results from (1) altered extracellular matrix constraints for horizontal growth and (2) uncoupling of endochondral and perichondral growth that causes metaphyseal flaring. PSACH, an autosomal dominant disease, is linked to mutation of the cartilage oligomeric matrix protein (COMP) gene. Amino acid substitutions, deletions, or additions is proposed to alter COMP structure that cause its retention in the rough endoplasmic reticulum of growth plate chondrocytes, leading to (1) compositional and structural change of the extracellular matrix, and (2) altered cellular proliferation and volume expansion. Normal growth and development occurs in COMP gene knockout mice that do not synthesis COMP, demonstrating that a mutant COMP, not absence of COMP, is required for the PSACH phenotype. The mechanism by which mutant COMP induces a PSACH phenotype remains to be elucidated. At the University of Iowa a cell culture system has been developed whereby mutant COMP transgenes are introduced into chondrocytes and the expressed product COMP is retained in the endoplasmic reticulum. This readily manipulated system makes it possible to decipher systematically the system's cellular secretory processing pathway, in order to clarify the mechanism(s) by which the mutant COMP is retained within the endoplasmic reticulum. Concurrent with this is the development of transgenic mice

  7. Outcome of porous tantalum acetabular components for Paprosky type 3 and 4 acetabular defects.

    PubMed

    Batuyong, Eldridge D; Brock, Hugh S; Thiruvengadam, Nikhil; Maloney, William J; Goodman, Stuart B; Huddleston, James I

    2014-06-01

    Porous tantalum acetabular implants provide a potential solution for dealing with significant acetabular bone loss. This study reviews 24 acetabular revisions using tantalum implants for Paprosky type 3 and 4 defects. The mean Harris Hip Score improved from 35 ± 19 (range, 4-71) to 88 ± 14 (range, 41-100), p < 0.0001. Postoperative radiographs showed radiolucent lines in 14 hips with a mean width of 1.3 ± 1.0 mm (range, 0.27-4.37 mm). No gaps enlarged and 71% of them disappeared at a mean of 13 ± 10 months (range, 3-29 months). At a mean follow-up of 37 ± 14 months (range, 24-66 months), 22 reconstructions showed radiograpic evidence of osseointegration (92%). The two failures were secondary to septic loosening. When dealing with severe acetabular bone loss, porous tantalum acetabular components show promising short-term results. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. [Computer-assisted navigated cup placement in primary and secondary dysplastic hips].

    PubMed

    Haaker, R; Tiedjen, K; Rubenthaler, F; Stockheim, M

    2003-01-01

    The positioning of an acetabular implant has great influence on the range of motion as well as the charger of dislocation of total hip arthroplasty. Using modern CAS systems the reproduction of the cup position after three-dimensional planning based on computed tomography is possible. We investigated the reliability of the position of the acetabular implant in primary and secondary dysplastic cases. Within a prospective randomised study in a total of 100 hip replacements with postoperatively controlled cup position using a computed tomography, we reinvestigated especially the 18 dysplastic and two secondary dysplastic cases. In the dysplastic cases we could realise nearly the same anteversion angles (22.4 degrees to 21.5 degrees) with a bigger standard deviation (+/- 7.68 degrees to +/- 7.29) than in the normal collective. Even the inclination angles (44.5 degrees +/- 5.47 degrees) could be realized nearly the same as in the normal cases (42.3 degrees +/- 4.31 degrees). The depth of the cup implantation could be realised in 15 of 18 cases. The CAS system is helpful even in dysplastic cases. The advantage of three-dimensional preoperative CT-based planning is apparent. The surgeon is not able to plan and realise the ideal cup position in some individual.

  9. Explicit finite element modelling of the impaction of metal press-fit acetabular components.

    PubMed

    Hothi, H S; Busfield, J J C; Shelton, J C

    2011-03-01

    Metal press-fit cups and shells are widely used in hip resurfacing and total hip replacement procedures. These acetabular components are inserted into a reamed acetabula cavity by either impacting their inner polar surface (shells) or outer rim (cups). Two-dimensional explicit dynamics axisymmetric finite element models were developed to simulate these impaction methods. Greater impact velocities were needed to insert the components when the interference fit was increased; a minimum velocity of 2 m/s was required to fully seat a component with a 2 mm interference between the bone and outer diameter. Changing the component material from cobalt-chromium to titanium alloy resulted in a reduction in the number of impacts on the pole to seat it from 14 to nine. Of greatest significance, it was found that locking a rigid cap to the cup or shell rim resulted in up to nine fewer impactions being necessary to seat it than impacting directly on the polar surface or using a cap free from the rim of the component, as is the case with many commercial resurfacing cup impaction devices currently used. This is important to impactor design and could make insertion easier and also reduce acetabula bone damage.

  10. Usefulness of measuring acetabular anterior coverage using a tomosynthesis imaging system.

    PubMed

    Ohtsuru, Tadahiko; Morita, Yasuyuki; Horiuchi, Yuhei; Murata, Yasuaki; Shimamoto, Shuji; Morita, Yuji; Munakata, Yutaro; Kato, Yoshiharu

    2017-02-21

    The purpose of this study was to compare the usefulness of measuring acetabular anterior coverage by tomosynthesis and false profile (FP) radiography. 70 hips in 35 patients who were diagnosed with early stage osteoarthritis of the hip, and 60 hips from 30 healthy volunteers were analysed. Plain FP radiographs were taken, and vertical-centre-anterior margin (FP-VCA) angles were measured. Acetabular anterior coverage was measured in the natural standing position using a tomosynthesis imaging system in the sagittal plane. As with FP radiography, we measured vertical-centre-anterior margin (TS-VCA) angles. The median values of the FP-VCA angle, and TS-VCA angle were 43.8°, 54.4°, respectively. The TS-VCA angle was significantly larger than the FP-VCA angle. For FP radiographs, the intraobserver intraclass correlation coefficient (ICC) was 0.68, and the interobserver ICC was 0.79. For tomosynthesis sagittal images, the intraobserver ICC was 0.85, and the interobserver ICC was 0.92. There was a strong positive correlation between the TS-VCA angle and the FP-VCA angle. When the FP-VCA angle was 25°, the TS-VCA angle was 35° in regression analysis. Measuring acetabular anterior coverage using sagittal plane tomosynthesis correlates well with FP radiography. Regardless of the presence of acetabular deformities, tomosynthesis demonstrated high reproducibility, simple posture setting, low effective doses, and high versatility. A cut-off value of 35° was useful for the detection of developmental dysplasia of the hip joint using the TS-VCA angle.

  11. Spinal Realignment for Adult Deformity: Three-column Osteotomies Alter Total Hip Acetabular Component Positioning.

    PubMed

    Barry, Jeffrey J; Yucekul, Altug; Theologis, Alexander A; Hansen, Erik N; Ames, Christopher; Deviren, Vedat

    2017-02-01

    A goal of adult spinal deformity surgery is correction of sagittal imbalance by increasing lumbar lordosis (LL), allowing a previously retroverted pelvis to normalize as evidenced by decreases in pelvic tilt (PT). Realignment of pelvic orientation may alter the position of preexisting total hip arthroplasties (THAs). Twenty-seven patients with unilateral THA who underwent thoracolumbar fusions for adult spinal deformity from the pelvis to L1 or above were retrospectively reviewed (levels fused, 10.3 [range, 6 to 17]; age, 70 ± 9 years). Comparisons of preoperative and postoperative spinal deformity parameters, acetabular tilt (AT), and acetabular cup abduction angle (CAA) were performed, with subgroup analysis for those who had undergone three-column osteotomy and those who had not. Preoperative deformity was severe, with findings of a sagittal vertical axis >9 cm, PT >25°, and pelvic incidence-LL >20°. Postoperatively, AT decreased significantly (-7° ± 10°; P < 0.001), signifying relative acetabular retroversion. Comparing patients with three-column osteotomy versus those without, AT changes were greater in those with three-column osteotomy (11° ± 7° and -2 ± 10°, respectively; P = 0.024). AT was significantly correlated with changes of PT (r = 0.704; P < 0.001) and LL (r = -0.481; P = 0.011). AT decreased (ie, retroverted) 1° for every 3.23° of LL or 1.13° of PT correction. The coronal plane CAA did not change substantially. Spinal deformity correction, with techniques such as three-column osteotomy, result in significant THA acetabular component repositioning in the sagittal plane. Resultant decreased AT (ie, retroversion) theoretically may affect tribology, wear, and joint stability and warrants further investigation.

  12. Comparison of Head Center Position and Screw Fixation Options Between a Jumbo Cup and an Offset Center of Rotation Cup in Revision Total Hip Arthroplasty: A Computer Simulation Study.

    PubMed

    Faizan, Ahmad; Black, Brandon J; Fay, Brian D; Heffernan, Christopher D; Ries, Michael D

    2016-01-01

    Jumbo acetabular cups are commonly used in revision total hip arthroplasty (THA). A straightforward reaming technique is used which is similar to primary THA. However, jumbo cups may also be associated with hip center elevation, limited screw fixation options, and anterior soft tissue impingement. A partially truncated hemispherical shell was designed with an offset center of rotation, thick superior rim, and beveled anterior and superior rims as an alternative to a conventional jumbo cup. A three dimensional computer simulation was used to assess head center position and safe screw trajectories. Results of this in vitro study indicate that a modified hemispherical implant geometry can reduce head center elevation while permitting favorable screw fixation trajectories into the pelvis in comparison to a conventional jumbo cup.

  13. Acetabular blood flow during total hip arthroplasty

    PubMed Central

    ElMaraghy, Amr W.; Schemitsch, Emil H.; Waddell, James P.

    2000-01-01

    Objective To determine the immediate effect of reaming and insertion of the acetabular component with and without cement on periacetabular blood flow during primary total hip arthroplasty (THA). Design A clinical experimental study. Setting A tertiary referral and teaching hospital in Toronto. Patients Sixteen patients (9 men, 7 women) ranging in age from 30 to 78 years and suffering from arthritis. Intervention Elective primary THA with a cemented (8 patients) and noncemented (8 patients) acetabular component. All procedures were done by a single surgeon who used a posterior approach. Main outcome measure Acetabular bone blood-flow measurements made with a laser Doppler flowmeter before reaming, after reaming and after insertion of the acetabular prosthesis. Results Acetabular blood flow after prosthesis insertion was decreased by 52% in the noncemented group (p < 0.001) and 59% in the cemented group (p < 0.001) compared with baseline (prereaming) values. Conclusion The significance of these changes in periacetabular bone blood flow during THA may relate to the extent of bony ingrowth, periprosthetic remodelling and ultimately the incidence of implant failure because of aseptic loosening. PMID:10851413

  14. Natural acetabular orientation in arthritic hips.

    PubMed

    Goudie, S T; Deakin, A H; Deep, K

    2015-01-01

    Acetabular component orientation in total hip arthroplasty (THA) influences results. Intra-operatively, the natural arthritic acetabulum is often used as a reference to position the acetabular component. Detailed information regarding its orientation is therefore essential. The aim of this study was to identify the acetabular inclination and anteversion in arthritic hips. Acetabular inclination and anteversion in 65 symptomatic arthritic hips requiring THA were measured using a computer navigation system. All patients were Caucasian with primary osteoarthritis (29 men, 36 women). The mean age was 68 years (SD 8). Mean inclination was 50.5° (SD 7.8) in men and 52.1° (SD 6.7) in women. Mean anteversion was 8.3° (SD 8.7) in men and 14.4° (SD 11.6) in women. The difference between men and women in terms of anteversion was significant (p = 0.022). In 75% of hips, the natural orientation was outside the safe zone described by Lewinnek et al (anteversion 15° ± 10°; inclination 40° ± 10°). When using the natural acetabular orientation to guide component placement, it is important to be aware of the differences between men and women, and that in up to 75% of hips natural orientation may be out of what many consider to be a safe zone. Cite this article: Bone Joint Res 2015;4:6-10. ©2015 The British Editorial Society of Bone & Joint Surgery.

  15. Effect of centre-edge angle on clinical and quality of life outcomes after arthroscopic acetabular labral debridement.

    PubMed

    Wu, Ziying; Chen, Shiyi; Li, Yunxia; Li, Hong; Chen, Jiwu

    2016-07-01

    The aim of this study was to compare clinical and quality of life outcomes following arthroscopic acetabular labral debridement between patients with different centre-edge (CE) angle. A total of 79 patients who underwent hip labral debridement were enrolled in this study. Radiographic measurements of CE angle were collected, and patients were assigned into a normal group (25° < CE angle <40°, n = 68) and dysplasia group (CE angle <20°, n = 11). Clinical outcomes were evaluated by modified Harris Hip Score (mHHS), Hip Outcome Score (HOS) for activities of daily living (ADL) and sports and Short Form 12 (SF-12). At the final follow-up, the normal group showed significant improvements in mHHS, HOS (ADL and sports) and SF-12 (P < 0.05). However, the dysplasia group revealed significant improvements in mHHS, HOS (ADL) and SF-12 physical component summary (PCS) (P < 0.05) and no significant changes in HOS sports and SF-12 mental component summary (MCS) (P > 0.05). Additionally, there was a greater improvement in clinical scores post-operatively in the normal group compared with the dysplasia group (P < 0.05). Arthroscopic acetabular labral debridement resulted in significantly greater clinical and quality of life outcomes in patients with CE angle >25° compared with patients with CE angle < 20°.

  16. Cups and Downs

    ERIC Educational Resources Information Center

    Stewart, Ian

    2012-01-01

    Martin Gardner wrote about a coin-flipping trick, performed by a blindfolded magician. The paper analyses this trick, and compares it with a similar trick using three cups flipped in pairs. Several different methods of analysis are discussed, including a graphical analysis of the state space and a representation in terms of a matrix. These methods…

  17. Compact rotating cup anemometer

    NASA Technical Reports Server (NTRS)

    Wellman, J. B.

    1968-01-01

    Compact, collapsible rotating cup anemometer is used in remote locations where portability and durability are factors in the choice of equipment. This lightweight instrument has a low wind-velocity threshold, is capable of withstanding large mechanical shocks while in its stowed configuration, and has fast response to wind fluctuations.

  18. Cups and Downs

    ERIC Educational Resources Information Center

    Stewart, Ian

    2012-01-01

    Martin Gardner wrote about a coin-flipping trick, performed by a blindfolded magician. The paper analyses this trick, and compares it with a similar trick using three cups flipped in pairs. Several different methods of analysis are discussed, including a graphical analysis of the state space and a representation in terms of a matrix. These methods…

  19. Complementary Coffee Cups

    ERIC Educational Resources Information Center

    Banchoff, Thomas

    2006-01-01

    What may have been the birth of a new calculus problem took place when the author noticed that two coffee cups, one convex and one concave, fit nicely together, and he wondered which held more coffee. The fact that their volumes were about equal led to the topic of this article: complementary surfaces of revolution with equal volumes.

  20. The perennial cup anemometer

    NASA Astrophysics Data System (ADS)

    Kristensen, L.

    1999-01-01

    A short version of the history of the cup anemometer precedes a more technical discussion of the special features of this instrument. These include its extremely linear calibration and the non-linearity of its response to wind speed changes. A simple conceptual model by Schrenk is used to demonstrate this and to explain why the cup anemometer is able to start from a zero rotation rate at zero wind to one corresponding to a sudden change in the ambient wind speed to a finite value. The same model is used to show that the cup anemometer should be characterized by a distance constant rather than by a time constant. The bias in the measured mean wind speed due to the random variations in the three velocity components is discussed in terms of standard, semiquantitative turbulence models, and the main thesis is that this bias is overwhelmingly dominated by the fluctuations of the lateral wind velocity component, i.e. the wind component perpendicular to the mean wind direction, and not, as is often assumed, by the longitudinal wind velocity component. It is shown theoretically and tested experimentally that the bias due to lateral wind velocity fluctuations can be significantly reduced by means of a special data processing of the simultaneous signals from a cup anemometer and a wind vane. This means that, with care, the overall overspeeding can be reduced to less than 1%.

  1. Complementary Coffee Cups

    ERIC Educational Resources Information Center

    Banchoff, Thomas

    2006-01-01

    What may have been the birth of a new calculus problem took place when the author noticed that two coffee cups, one convex and one concave, fit nicely together, and he wondered which held more coffee. The fact that their volumes were about equal led to the topic of this article: complementary surfaces of revolution with equal volumes.

  2. Genetics Home Reference: Czech dysplasia

    MedlinePlus

    ... Email Facebook Twitter Home Health Conditions Czech dysplasia Czech dysplasia Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Czech dysplasia is an inherited condition that affects joint ...

  3. Retinal dysplasia of holoprosencephaly.

    PubMed

    Gorovoy, Ian R; Layer, Noelle; de Alba Campomanes, Alejandra G

    2014-03-04

    Retinal dysplasia occurs in the setting of sporadic and syndromic holoprosencephaly, which often has associated ocular malformations. The pathology of this dysplasia, which includes rosettes, has been previously described. However, its funduscopic findings have not been well documented. The authors present the fundus images of a patient with severe holoprosencephaly with retinal dysplasia and bilateral optic nerve colobomas that resulted in death 2 weeks after birth.

  4. What is the Impact of a Spinal Fusion on Acetabular Implant Orientation in Functional Standing and Sitting Positions?

    PubMed

    Lazennec, Jean Y; Clark, Ian C; Folinais, Dominique; Tahar, Imen N; Pour, Aidin E

    2017-10-01

    This study used EOS imaging of primary total hip arthroplasty (THA) patients, with and without predating spinal fusion, to investigate (1) the impact of spinal fusion on acetabular implant anteversion and inclination, and (2) whether more extensive spinal fusion (fusion starting above the thoracolumbar junction or extension of fusion to the sacrum) affects acetabular implant orientation differently than lumbar only spinal fusion. Ninety-three patients had spinal fusion (case group), and 150 patients were without spinal fusion (controls). None of the patients experienced dislocation. The change in sacral slope (SS) and cup orientation from standing to sitting was measured. Mean SS change from the standing to sitting positions was -7.9°in the fusion group vs -18.4°in controls (P = .0001). Mean change in cup inclination from the standing to sitting positions was 4.9°in the fusion group vs 10.2°in controls (P = .0001). Mean change in cup anteversion from standing to sitting positions was 7.1°in the fusion group vs 12.1°in controls (P = .0001). For each additional level of spinal fusion, the change in SS from standing to sitting positions decreased by 1.6(95% confidence interval [CI], 2.2073-1.0741), the change in cup inclination decreased by 0.8(95% CI, 0.380-1.203), and the change in cup anteversion decreased by 0.9(95% CI, 0.518-1.352; P < .001 in all cases). Patients with spinal fusion demonstrated less adaptability of the lumbosacral junction. Longer spinal fusion or inclusion of the pelvis in the fusion critically impacts hip-spine biomechanics and significantly affects the ability to compensate in the standing-to-sitting transition. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Acetabular pneumatocyst containing air-fluid level.

    PubMed

    Narváez, J A; Narváez, J; Rodríguez-Mijarro, M; Quintero, J C

    1999-01-01

    The presence of intraosseous gas most commonly occurs in osteomyelitis, vacuum phenomenon, and postsurgery or posttraumatic states. Several cases of subchondral gas-filled lesions, called pneumatocysts, have also been described in the sacroiliac joint and clavicle, none of them with intralesional air-fluid level. These pneumatocysts are innocuous lesions of uncertain origin. We describe one case of acetabular pneumatocyst containing air-fluid level in a 62-year-old man with long-standing ankylosing spondylitis involving hip joint. To our knowledge, this is the first reported case of a pneumatocyst in an acetabular location containing air-fluid level.

  6. Bernese periacetabular osteotomy for hip dysplasia: Surgical technique and indications.

    PubMed

    Kamath, Atul F

    2016-05-18

    For young, active patients with healthy hip cartilage, pelvic osteotomy is a surgical option in to address hip pain and to improve mechanical loading conditions related to dysplasia. Hip dysplasia may lead to arthrosis at an early age due to poor coverage of the femoral head and abnormal loading of the joint articulation. In patients with symptomatic dysplasia and closed triradiate cartilage (generally over age 10), including adolescents and young adults (generally up to around age 40), the Bernese periacetabular osteotomy (PAO) is a durable technique for addressing underlying structural deformity. The PAO involves a modified Smith-Petersen approach. Advantages of the Bernese osteotomy include preservation of the weight-bearing posterior column of the hemi-pelvis, preservation of the acetabular blood supply, maintenance of the hip abductor musculature, and the ability to effect powerful deformity correction about an ideal center of rotation. There is an increasing body of evidence that preservation of the native hip can be improved through pelvic osteotomy. In contrast to hip osteotomy and joint preservation, the role of total hip arthroplasty in young, active patients with correctable hip deformity remains controversial. Moreover, the durability of hip replacement in young patients is inherently limited. Pelvic osteotomy should be considered the preferred method to address correctable structural deformity of the hip in the young, active patient with developmental dysplasia. The Bernese PAO is technically demanding, yet offers reproducible results with good long-term survivorship in carefully selected patients with preserved cartilage and the ability to meet the demands of rehabilitation.

  7. [Bernese periacetabular osteotomy for the treatment of severe hip dysplasia].

    PubMed

    Huang, Ye; Zhang, Hong; Liu, Qing; Jiang, Zeng-hui; Dou, Yong

    2010-02-15

    To analyze the mid-term clinical and radiographic results obtained with the Bernese periacetabular osteotomy for the treatment of severe hip dysplasia. From October 1997 to December 2002 20 hips of 18 patients were classified as having severe acetabular dysplasia (Severin classification Grade IVb). Preoperatively, all patients had hip pain, and sufficient hip joint congruency on functional radiographs. All 20 hips underwent Bernese periacetabular osteotomy. Postoperatively, the hips were assessed radiographically on center edge angle (CE), acetabular roof obliquity and the progression of osteoarthritis. Clinical results and hip function were measured with the Harris hip score at an average of 6.2 years follow-up. Comparison of preoperative and follow-up radiographs demonstrated significant improvements in the lateral CE angle, the anterior CE angle, and roof obliquity. The average Harris hip score improved from 78.5 points preoperatively to 91.1 points at the time of the latest follow-up. Fourteen of 18 patients were satisfied with the result of the surgery, and 16 of 20 hips had a good or excellent clinical result. Under-correction occurred in 5 hips. The Bernese periacetabular osteotomy is an effective procedure for surgical correction of the severe dysplastic hip. This osteotomy can predictably obtain major reorientation of the acetabulum in all planes. The clinical results in the mid-term follow-up are encouraging.

  8. The acetabular point: a morphological and ontogenetic study

    PubMed Central

    RISSECH, C.; SAÑUDO, J. R.; MALGOSA, A.

    2001-01-01

    The acetabular point was analysed by studying human pelvic bones from 326 individuals ranging from newborns to age 97 y. The bones were categorised into 3 groups according to the degree of fusion for the 3 elements of the pelvis: nonfused (59), semifused (5) and fused (262). The acetabular point in immature pelvic bones is clearly represented by the point of the fusion lines for each bony element at the level of the acetabular fossa. In adult pelvic bones the acetabular fossa has an irregular clover-leaf shape, the superior lobe being smaller than the anterior and posterior lobes. Cross-sectional analysis of acetabular morphology suggested that the acetabular point in adult pelvic bones is always represented by the indentation between the superior and the anterior lobes of the acetabular fossa. PMID:11465866

  9. The effect of the Rim Cutter on cement pressurization and penetration on cemented acetabular fixation in total hip arthroplasty: an in vitro study.

    PubMed

    Smith, B N; Lee, A J C; Timperley, A J; Whitehouse, S L; Crawford, R W

    2010-01-01

    The Rim Cutter (Stryker Orthopedics, Mahwah, New Jersey) is a tool designed to cut a ledge inside the rim of the acetabulum, onto which a precisely trimmed, cemented, flanged cup can be fitted. The aim was to investigate the effect of the Rim Cutter on the intra-acetabular cement mantle pressure and the depth of cement penetration during cup insertion. The study had two parts. In the first part, hemi-pelvis models were fitted with pressure sensors. Pressure in the acetabulum was measured on insertion of a conventional cemented flanged cup with and without the use of a Rim Cutter to prepare the rim of the acetabulum. The second part assessed cement penetration when the same cups were inserted into a foam shell model. The shell was mounted in a jig and had holes drilled in it; the distance that cement penetrated into the holes was measured. A significant increase in cement pressure at the apex (p = 0.04) and the rim (p = 0.004) is seen when the Rim Cutter is used. Cement penetration in the Rim Cutter group was significantly increased at the rim of the acetabulum (p = 0.003). Insertion of a flanged cup after the acetabulum is prepared with the Rim Cutter leads to a significant increase in cement pressure and penetration during cup insertion in vitro when compared with conventional flanged cups.

  10. Modified Faraday cup

    DOEpatents

    Elmer, J.W.; Teruya, A.T.; O`Brien, D.W.

    1996-09-10

    A tomographic technique for measuring the current density distribution in electron beams using electron beam profile data acquired from a modified Faraday cup to create an image of the current density in high and low power beams is disclosed. The modified Faraday cup includes a narrow slit and is rotated by a stepper motor and can be moved in the x, y and z directions. The beam is swept across the slit perpendicular thereto and controlled by deflection coils, and the slit rotated such that waveforms are taken every few degrees from 0{degree} to 360{degree} and the waveforms are recorded by a digitizing storage oscilloscope. Two-dimensional and three-dimensional images of the current density distribution in the beam can be reconstructed by computer tomography from this information, providing quantitative information about the beam focus and alignment. 12 figs.

  11. Modified Faraday cup

    DOEpatents

    Elmer, John W.; Teruya, Alan T.; O'Brien, Dennis W.

    1996-01-01

    A tomographic technique for measuring the current density distribution in electron beams using electron beam profile data acquired from a modified Faraday cup to create an image of the current density in high and low power beams. The modified Faraday cup includes a narrow slit and is rotated by a stepper motor and can be moved in the x, y and z directions. The beam is swept across the slit perpendicular thereto and controlled by deflection coils, and the slit rotated such that waveforms are taken every few degrees form 0.degree. to 360.degree. and the waveforms are recorded by a digitizing storage oscilloscope. Two-din-tensional and three-dimensional images of the current density distribution in the beam can be reconstructed by computer tomography from this information, providing quantitative information about the beam focus and alignment.

  12. Comparison of Conventional Polyethylene Wear and Signs of Cup Failure in Two Similar Total Hip Designs

    PubMed Central

    Pace, Thomas B.; Keith, Kevin C.; Snider, Rebecca G.; Tanner, Stephanie L.; DesJardins, John D.

    2013-01-01

    Multiple factors have been identified as contributing to polyethylene wear and debris generation of the acetabular lining. Polyethylene wear is the primary limiting factor in the functional behavior and consequent longevity of a total hip arthroplasty (THA). This retrospective study reviewed the clinical and radiographic data of 77 consecutive THAs comparing in vivo polyethylene wear of two similar acetabular cup liners. Minimum follow-up was 7 years (range 7–15). The incidence of measurable wear in a group of machined liners sterilized with ethylene oxide and composed of GUR 1050 stock resin was significantly higher (61%) than the compression-molded, GUR 1020, O2-free gamma irradiation sterilized group (24%) (P = 0.0004). Clinically, at a 9-year average followup, both groups had comparable HHS scores and incidence of thigh or groin pain, though the machined group had an increased incidence of osteolysis and annual linear wear rate. PMID:23662210

  13. Periprosthetic acetabular fracture associated with extensive osteolysis.

    PubMed

    Chatoo, M; Parfitt, J; Pearse, M F

    1998-10-01

    Periprosthetic fracture of the acetabulum is an uncommon complication of total hip arthroplasty. The management is reported to be difficult, and complications such as nonunion and implant loosening are common. We described herein a case of nontraumatic periprosthetic acetabular fracture associated with significant osteolysis, which was successfully managed by addressing the fracture and osteolysis independently.

  14. Radiological findings for hip dysplasia at skeletal maturity. Validation of digital and manual measurement techniques.

    PubMed

    Engesæter, Ingvild Øvstebø; Laborie, Lene Bjerke; Lehmann, Trude Gundersen; Sera, Francesco; Fevang, Jonas; Pedersen, Douglas; Morcuende, José; Lie, Stein Atle; Engesæter, Lars Birger; Rosendahl, Karen

    2012-07-01

    To report on intra-observer, inter-observer, and inter-method reliability and agreement for radiological measurements used in the diagnosis of hip dysplasia at skeletal maturity, as obtained by a manual and a digital measurement technique. Pelvic radiographs from 95 participants (56 females) in a follow-up hip study of 18- to 19-year-old patients were included. Eleven radiological measurements relevant for hip dysplasia (Sharp's, Wiberg's, and Ogata's angles; acetabular roof angle of Tönnis; articulo-trochanteric distance; acetabular depth-width ratio; femoral head extrusion index; maximum teardrop width; and the joint space width in three different locations) were validated. Three observers measured the radiographs using both a digital measurement program and manually in AgfaWeb1000. Inter-method and inter- and intra-observer agreement were analyzed using the mean differences between the readings/readers, establishing the 95% limits of agreement. We also calculated the minimum detectable change and the intra-class correlation coefficient. Large variations among different radiological measurements were demonstrated. However, the variation was not related to the use of either the manual or digital measurement technique. For measurements with greater absolute values (Sharp's angle, femoral head extrusion index, and acetabular depth-width ratio) the inter- and intra-observer and inter-method agreements were better as compared to measurements with lower absolute values (acetabular roof angle, teardrop and joint space width). The inter- and intra-observer variation differs notably across different radiological measurements relevant for hip dysplasia at skeletal maturity, a fact that should be taken into account in clinical practice. The agreement between the manual and digital methods is good.

  15. Effect of acetabular modularity on polyethylene wear and osteolysis in total hip arthroplasty.

    PubMed

    Young, Anthony M; Sychterz, Christi J; Hopper, Robert H; Engh, Charles A

    2002-01-01

    Debris from polyethylene wear causes osteolysis. In this study, we examined the effect of acetabular liner modularity on polyethylene wear and osteolysis. We compared forty-one hips (thirty-nine patients) treated with a nonmodular, porous-coated acetabular component with a matched group of forty-one hips (forty patients) treated with a modular acetabular component. The groups were matched by patient gender and age, type of polyethylene material, method of polyethylene sterilization, femoral head size and manufacturer, and stem manufacturer. The mean follow-up period was 5.3 years (range, 3.8 to 6.8 years) for the nonmodular group and 5.5 years (range, 3.8 to 8.0 years) for the modular group. Using serial radiographs and a computer-assisted method, we measured two-dimensional head penetration into the polyethylene liner. Temporal head-penetration data and linear regression analysis were used to calculate the true wear rates. The nonmodular acetabular components demonstrated a lower, but not a significantly lower, mean true wear rate than did the modular components (0.11 compared with 0.16 mm/yr, p = 0.22), and they were associated with a significantly lower rate of osteolysis (2% compared with 22%, p = 0.01). In addition, the true wear rates of the nonmodular components were less variable than those of the modular components. The 95% confidence interval for the wear rates of the nonmodular components (0.08 to 0.13 mm/yr) was nearly half that of the modular group (0.11 to 0.20 mm/yr). The lower and more consistent true wear rates of the nonmodular components could be attributed to the fact that these cups were designed to have greater liner-shell conformity, greater liner thickness, and less liner-shell micromotion than modular components. These design factors could have favorably altered the stress distribution throughout the liner and could have thereby decreased wear. Although nonmodular components may present a partial solution to the problems of wear and

  16. Dual mobility bearings withstand loading from steeper cup-inclinations without substantial wear.

    PubMed

    Loving, LaQuawn; Herrera, Lizeth; Banerjee, Samik; Heffernan, Christopher; Nevelos, Jim; Markel, David C; Mont, Michael A

    2015-03-01

    Steep cup abduction angles with adverse joint loading may increase traditional polyethylene bearing wear in total hip arthroplasties. However, there have been few reports evaluating the effect of cup inclination on the wear of dual-mobility devices. In a hip joint simulation, we compared the short-term wear of two-sizes of modular highly cross-linked dual-mobility bearings (28 mm femoral head diameter/42 mm polyethylene insert outer diameter/54 mm acetabular shell diameter; 22.2 mm femoral head diameter/36 mm polyethylene insert outer diameter/48 mm acetabular shell diameter) at 50 and 65° of cup inclination with modular 28 mm femoral head on 54 mm cup diameter metal-on-highly cross-linked polyethylene bearings. Increasing inclination from 50-65° had no changes in volumetric wear of 28/42/54 mm (mean, 1.7 vs. 1.2 mm3 /million cycles, respectively; p = 0.50) and 22.2/36/48 mm (mean, 1.7 vs. 1.2 mm3/million cycles, respectively; p = 0.48) dual mobility bearings. At 65°, 22.2/36/48 mm dual-mobility bearings had lower volumetric loss (mean, 2.2 vs. 6.3 mm(3) ; p = 0.03) and wear rates (mean, 1.2 vs. 2.7 mm3/million cycles; p = 0.02) compared to metal-on-highly cross-linked polyethylene bearings. Modern-generation dual-mobility designs with highly cross-linked polyethylenes may potentially withstand edge-loading from steeper cup-inclinations without substantial decreases in wear.

  17. Total hip replacements done without cement after acetabular fractures: a 4- to 8-year follow-up study.

    PubMed

    Huo, M H; Solberg, B D; Zatorski, L E; Keggi, K J

    1999-10-01

    Twenty-one patients (21 hips) underwent cementless total hip replacement surgeries for previous acetabular fractures. The mean age at the time of hip replacement was 52 years (range, 23-78 years). The mean follow-up was 65 months (range, 48-104 months). One hip required revision of the stem secondary to a periprosthetic femur fracture from a fall at 3 months after surgery. Good to excellent clinical rating was achieved and maintained in 19 hips. Radiographic evaluation demonstrated stable cup and stem fixation in 17 and 15 hips. Only 1 patient with radiographic loosening of the components was sufficiently symptomatic. The results in this series appeared slightly better than those reported previously in hip replacements done with cement at comparable medium-term follow-up. The mechanical failure rates remained high in this patient population: 19% for the cups and 29% for the stems.

  18. ION PRODUCING MECHANISM (CHARGE CUPS)

    DOEpatents

    Brobeck, W.W.

    1959-04-21

    The problems of confining a charge material in a calutron and uniformly distributing heat to the charge is described. The charge is held in a cup of thermally conductive material removably disposed within the charge chamber of the ion source block. A central thermally conducting stem is incorporated within the cup for conducting heat to the central portion of the charge contained within the cup.

  19. The effect of Dega acetabuloplasty and Salter innominate osteotomy on acetabular remodeling monitored by the acetabular index in walking DDH patients between 2 and 6 years of age: short- to middle-term follow-up.

    PubMed

    El-Sayed, Mohamed; Ahmed, Tarek; Fathy, Sameh; Zyton, Hosam

    2012-12-01

    The surgical management of neglected developmental dysplasia of the hip (DDH) in walking children has always been a challenge to orthopedic surgeons. The aim of this study was to evaluate the short- to middle-term clinical and radiographic results of the management of DDH. Patients less than 6 years old using two of the most commonly used osteotomies, namely, Salter innominate osteotomy and the Dega acetabuloplasty. Special attention was paid to acetabular remodeling after concentric reduction, which was monitored by the acetabular index, that, in turn, was measured preoperatively, immediately postoperatively, every 6 months, and at the final follow-up examination. The final overall clinical end results were favorable (excellent or good) in 93 hips (85.3 %). There was a marked improvement of the acetabular coverage during the follow-up period, which proved the good remodeling potential of the acetabulum for this particular age group after concentric reduction was achieved and maintained. Both osteotomy types were found to be adequate for the management of neglected walking DDH patients under the age of 6 years.

  20. Ghosal Type Hematodiaphyseal Dysplasia.

    PubMed

    Jeevan, Amrit; Doyard, Mathilde; Kabra, Madhulika; Daire, Valerie Cormier; Gupta, Neerja

    2016-04-01

    Ghosal Type Hematodiaphyseal Dysplasia is an autosomal recessive disorder characterized by refractory anemia and diaphyseal bone dysplasia. A 3 y 9 mo-old male child presented with progressive anemia and bowing of thighs. Child was found to have a previously reported homozygous point mutation c.1238G>A, (p.Arg413Glu) in Exon 16 of TBXAS1 gene. Low dose steroid therapy resulted in normalization of hemoglobin and prevented further progression of bony changes. Refractory anemia in association with bony deformities should prompt pediatricians to investigate for inherited bony dysplasia.

  1. Recognition of minor adult hip dysplasia: which anatomical indices are important?

    PubMed

    Pereira, Felipe; Giles, Andrew; Wood, Gavin; Board, Tim N

    2014-01-01

    The rise in popularity of hip arthroscopy has led to a renewed interest in mild hip dysplasia. There is a lack of clarity in the literature regarding both the diagnosis and management of such patients. The aim of this study was to analyse the relative importance of and the inter-relationship between the classically described anatomical indices of dysplasia.One hundred and fifty hips with varying degrees of hip dysplasia were studied. The following were measured: centre-edge (CE), Sharp's and Tönnis angles, acetabular head index (AHI), and acetabular index of depth to width (AIDW). Spearman's correlation coefficient was calculated.Using the CE angle 82 hips were classified as normal and 68 dysplastic. Of the 82 patients with a normal CE angle, 20-39% were dysplastic on at least one other variable. The CE angle did not have a significant correlation to other variables. The remaining four variables showed inter-correlations between 0.26 and 0.54. Overall the Tönnis angle showed the strongest correlation with the other variables. In the patient group with CE angles 21o to 25o (minor dysplasia) 72% of hips had Tönnis angles greater than 10o and 28% had angles greater than or equal to 15o indicating the great variability in the level of dysplasia within this group.In patients with mild dysplasia we have shown that measurement of a single anatomical variable may lead to under-diagnosis. We recommend the measurement the CE angle combined with at least one other variable and suggest the use of the Tönnis angle.

  2. Gordon Bennett Airplane Cup

    NASA Technical Reports Server (NTRS)

    Margoulis, W

    1921-01-01

    The characteristics of the airplanes built for the Gordon Bennet Airplane Cup race that took place on September 28, 1920 are described. The airplanes are discussed from a aerodynamical point of view, with a number of new details concerning the French machines. Also discussed is the regulation of future races. The author argues that there should be no limitations on the power of the aircraft engines. He reasons that in the present state of things, liberty with regard to engine power does not lead to a search for the most powerful engine, but for one which is reliable and light, thus leading to progress.

  3. [Squeaking as a cause for revision of a composite ceramic cup].

    PubMed

    Schlegel, U J; Bishop, N; Sobottke, R; Perka, C; Eysel, P; Morlock, M M

    2011-09-01

    Squeaking in total hip arthroplasty (THA) has been observed only in hard-on-hard bearings, such as ceramic-on-ceramic or metal-on-metal. We report the case of a patient with a squeaking THA who had undergone multiple femoral head revisions combined with a composite ceramic cup (polyurethane, ceramic). Squeaking started 6 years postoperatively and acetabular revision was necessary to resolve the issue. Secondary deformation of the inlay resulted in clamping of the femoral head and increased friction. This should be considered when assessing and advising patients with squeaking THA when composite ceramic components are involved.

  4. Prevalence of developmental dysplasia of the hip in children with clubfoot.

    PubMed

    Chou, Daud Ts; Ramachandran, Manoj

    2013-10-01

    The relationship between congenital talipes equinovarus (CTEV) and developmental dysplasia of the hip (DDH) remains uncertain. The role of routine hip screening in children with CTEV is debated. A recent study has found a high incidence of DDH in patients with CTEV. The aim of our study was to determine the true prevalence of radiographic hip dysplasia and identify the need for routine hip screening in patients treated for CTEV. From a single centre database of 165 children consisting of 260 CTEV, a prospective radiological prevalence study of 101 children was performed over a period of 3 months. A single anterior-posterior pelvic radiograph was performed at a minimum age of 5 months. The DDH was determined by a single senior investigator based on the age-adjusted acetabular index (AI) as described by Tonnis. There were no dislocations or subluxations. According to the age-adjusted AI, 16 children had 'light' dysplasia and one child had 'severe' dysplasia. The child with severe dysplasia was known to have DDH and had already undergone treatment. The 16 children with light dysplasia did not require any form of treatment. Out of one hundred and one children with CTEV, only one had DDH requiring treatment. This is consistent with the majority of the literature supporting the premise that there is no true association between CTEV and DDH. We, therefore, feel that routine hip screening for children with CTEV is not supported by current evidence and cannot be recommended.

  5. The long-term outcome of 755 consecutive constrained acetabular components in total hip arthroplasty examining the successes and failures.

    PubMed

    Berend, Keith R; Lombardi, Adolph V; Mallory, Thomas H; Adams, Joanne B; Russell, Jackie H; Groseth, Kari L

    2005-10-01

    Constrained acetabular components can treat or prevent instability after total hip arthroplasty (THA). We examine long-term results of 755 consecutive constrained THA in 720 patients (1986-1993; 62 primary, 59 conversion, 565 revision, 60 reimplantation, and 9 total femur). Eighty-three patients (88 THAs) were lost before 10-year follow-up, leaving 639 patients (667 THAs) available for study. Dislocation occurred in 117 hips (17.5%), in 37 (28.9%) of 128 constrained for recurrent dislocation, and 46 (28.2%) of 163 with dislocation history. Other reoperations were for aseptic loosening (51, 7.6% acetabular; 28, 4.2% stem; 16, 2.4% combined), infection (40, 6.0%), periprosthetic fracture (19, 2.8%), stem breakage (2, 0.3%), cup malposition (1, 0.1%), dissociated insert (1, 0.1%), dissociated femoral head (1, 0.1%), and impingement of 1 broken (0.1%) and 4 (0.6%) dissociated constraining rings. Although constrained acetabular components prevented recurrent dislocation in 71.1%, they should be used cautiously, with a 42.1% long-term failure rate observed in this series. Dislocation was common despite constraint with previous history as a significant risk.

  6. Meralgia paresthetica and femoral acetabular impingement: a possible association.

    PubMed

    Ahmed, Aiesha

    2010-12-11

    Meralgia paresthetica consists of pain and dysesthesia in the anterolateral thigh. Etiology is divided into spontaneous and iatrogenic causes. To my knowledge this has never been attributed to femoral acetabular impingement. This case highlights the presence of lateral femoral cutaneous neuropathy in the setting of femoral acetabular impingement syndrome thus raising the possibility of an association. Femoral acetabular impingement; Lateral femoral cutaneous nerve; Dysesthesia; Nerve conduction studies.

  7. Meralgia Paresthetica and Femoral Acetabular Impingement: A Possible Association

    PubMed Central

    Ahmed, Aiesha

    2010-01-01

    Meralgia paresthetica consists of pain and dysesthesia in the anterolateral thigh. Etiology is divided into spontaneous and iatrogenic causes. To my knowledge this has never been attributed to femoral acetabular impingement. This case highlights the presence of lateral femoral cutaneous neuropathy in the setting of femoral acetabular impingement syndrome thus raising the possibility of an association. Keywords Femoral acetabular impingement; Lateral femoral cutaneous nerve; Dysesthesia; Nerve conduction studies PMID:22043261

  8. Preliminary analysis on the MD-4® plasma-sprayed titanium acetabular component☆

    PubMed Central

    de Araújo Loures, Elmano; Simoni, Leandro Furtado; Leite, Isabel Cristina Gonçalves; Loures, Daniel Naya; Loures, Clarice Naya

    2015-01-01

    Objectives To evaluate the short-term performance of a type of implant manufactured in Brazil. Methods This study analyzed a cohort of 60 patients who underwent implantation of MD-4® acetabular components during primary hip arthroplasty procedures performed between January 1, 2010, and August 1, 2012. The patients were studied retrospectively with regard to clinical behavior, stability and radiological osseointegration. The patients were followed up for a minimum of 12 months and a maximum of 42 months (mean: 27) and were evaluated by means of the Harris Hip Score, SF-36 questionnaire and serial conventional radiographs. Results All the components were radiologically stable, without evidence of migration or progressive radiolucency lines. On average, the Harris Hip Score evolved from 36.1 to 92.1 (p < 0.001) and the SF-36 showed significant increases in all its domains (p < 0.001). No differences were observed among patients with osteoarthrosis, osteonecrosis, hip dysplasia or other conditions. Conclusions The short-term results showed clinical and radiological signs of stability and osseointegration of the implants, which may represent a predictive factor regarding medium-term survival of this acetabular component. PMID:26229918

  9. Living with Bronchopulmonary Dysplasia

    MedlinePlus

    ... Living With Bronchopulmonary Dysplasia Caring for a premature infant can be challenging. You may have: Emotional pain, ... tiredness). Frustration that you can't breastfeed your infant right away. (You can pump and store your ...

  10. Cervical dysplasia - series (image)

    MedlinePlus

    Conization is a procedure in which a "cone" of tissue is removed. This procedure is performed for more advanced cervical dysplasia, which remains limited to the cervix (cervical intraepithelial neoplasia, high ...

  11. Cup Cylindrical Waveguide Antenna

    NASA Technical Reports Server (NTRS)

    Acosta, Roberto J.; Darby, William G.; Kory, Carol L.; Lambert, Kevin M.; Breen, Daniel P.

    2008-01-01

    The cup cylindrical waveguide antenna (CCWA) is a short backfire microwave antenna capable of simultaneously supporting the transmission or reception of two distinct signals having opposite circular polarizations. Short backfire antennas are widely used in mobile/satellite communications, tracking, telemetry, and wireless local area networks because of their compactness and excellent radiation characteristics. A typical prior short backfire antenna contains a half-wavelength dipole excitation element for linear polarization or crossed half-wavelength dipole elements for circular polarization. In order to achieve simultaneous dual circular polarization, it would be necessary to integrate, into the antenna feed structure, a network of hybrid components, which would introduce significant losses. The CCWA embodies an alternate approach that entails relatively low losses and affords the additional advantage of compactness. The CCWA includes a circular cylindrical cup, a circular disk subreflector, and a circular waveguide that serves as the excitation element. The components that make it possible to obtain simultaneous dual circular polarization are integrated into the circular waveguide. These components are a sixpost polarizer and an orthomode transducer (OMT) with two orthogonal coaxial ports. The overall length of the OMT and polarizer (for the nominal middle design frequency of 2.25 GHz) is about 11 in. (approximately equal to 28 cm), whereas the length of a commercially available OMT and polarizer for the same frequency is about 32 in. (approximately equal to 81 cm).

  12. World Cup Hopes

    NASA Technical Reports Server (NTRS)

    2002-01-01

    From May 31 to June 30 the biggest single-sport event in the world, the 2002 FIFA World Cup (tm), will be taking place in Asia. South Korea and Japan are acting as hosts for the event which is being held in Asia for the first time. This true-color image of the southern Korean peninsula and southern Japan was acquired on May 25, 2002, by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra satellite. Thirty-two nations are represented at this year's Finals including the 1998 champion France, European powers England and Italy, tournament favorite Argentina, and the United States. The finals are the culmination of a 2-year qualifying process which started with 132 nations competing in regional qualification tournaments. In the round-robin first round of the World Cup, the U.S. team will be competing against teams from Portugal, Poland, and South Korea. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  13. Source-to-detector distance and beam center do not affect radiographic measurements of acetabular morphology.

    PubMed

    Goldman, Ashton H; Hoover, Kevin B

    2017-04-01

    Multiple radiographic acquisition techniques have been evaluated for their effect on measurements of acetabular morphology. This cadaveric study examined the effect of two acquisition parameters not previously evaluated: beam center position and source-to-detector distance. This study also evaluated the effect of reader differences on measurements. Following calibration of measurements between two readers using five clinical radiographs (training), radiographs were obtained from two cadavers using four different source-to-detector distances and three different radiographic centers for a total of 12 radiographic techniques (experimental). Two physician readers acquired four types of measurements from each cadaver radiograph: lateral center edge angle, peak-to-edge distance, Sharp's angle, and the Tonnis angle. All measurements were evaluated for intra-class correlation coefficient (ICC), kappa statistics for hip dysplasia, and factors that resulted in measurement differences using a mixed statistical model. After training of the two physician readers, there was strong agreement in their hip morphology measurements (ICC 0.84-0.93), agreement in the presence of hip dysplasia (κ = 0.58-1.0), and no measurement difference between physician readers (p = 0.12-1.0). Experimental cadaver measurements showed moderate-to-strong agreement of the readers (ICC 0.74-0.93) and complete agreement on dysplasia (κ = 1). After accounting for reader and radiographic technique, there was no difference in hip morphology measurements (p = 0.83-0.99). In this cadaveric study, measurements of hip morphology were not affected by varying source-to-detector distance or beam center. We conclude that these acquisition parameters are not likely to affect the diagnosis of hip dysplasia in a clinical setting.

  14. Wear versus Thickness and Other Features of 5-Mrad Crosslinked UHMWPE Acetabular Liners

    PubMed Central

    Shen, Fu-Wen; Lu, Zhen

    2010-01-01

    Background The low wear rates of crosslinked polyethylenes provide the potential to use larger diameters to resist dislocation. However, this requires the use of thinner liners in the acetabular component, with concern that higher contact stresses will increase wear, offsetting the benefits of the crosslinking. Questions/purposes We asked the following questions: Is the wear of conventional and crosslinked polyethylene liners affected by ball diameter, rigidity of backing, and liner thickness? Are the stresses in the liner affected by thickness? Methods Wear rates were measured in a hip simulator and stresses were calculated using finite element modeling. Results Without crosslinking, the wear rate was 4% to 10% greater with a 36-mm diameter than a 28-mm diameter. With crosslinking, wear was 9% lower with a 36-mm diameter without metal backing and 4% greater with metal backing. Reducing the thickness from 6 mm to 3 mm increased the contact stress by 46%, but the wear rate decreased by 19%. Conclusions The reduction in wear with 5 Mrad of crosslinking was not offset by increasing the diameter from 28 mm to 36 mm or by using a liner as thin as 3 mm. Clinical Relevance The results indicate, for a properly positioned 5-Mrad crosslinked acetabular component and within the range of dimensions evaluated, neither wear nor stresses in the polyethylene are limiting factors in the use of larger-diameter, thinner cups to resist dislocation. PMID:20848244

  15. Acetabular bone loss in revision total hip arthroplasty: principles and techniques.

    PubMed

    Noordin, Shahryar; Masri, Bassam A; Duncan, Clive P; Garbuz, Donald S

    2010-01-01

    Bone stock deficiency presents the major challenge in acetabular reconstruction during revision hip arthroplasty. The preoperative assessment of acetabular bone stock before revision surgery is critical because the amount and location of pelvic osteolysis can determine the type and success of revision surgery. Traditionally, plain radiographs with AP and lateral views have been used for this purpose; however, Judet views can provide additional information about the integrity of the anterior and posterior columns. CT and MRI scans are indicated in selected patients. A variety of surgical options are available for treating Paprosky type 3 defects. Jumbo cups, the high hip center technique, impaction grafting, bilobed implants, antiprotrusio cages, and structural allografts, in addition to other types of implants, are part of the armamentarium available for revision hip arthroplasty. Segmental bone loss involving more than 50% of the acetabulum is one of the biggest challenges in revision hip replacement. The short-term clinical and radiographic results of treating these large defects with modular, highly porous metal components appear promising. However, potential problems with these components include their unknown long-term durability, potential for debris generation at the shell-augment interface, potential for fatigue failure, and the inability to restore bone stock if future revisions are needed.

  16. 3D Printing Aids Acetabular Reconstruction in Complex Revision Hip Arthroplasty

    PubMed Central

    DeBuitleir, Cathal; Soden, Philip; O'Donnchadha, Brian; Tansey, Anthony; Abdulkarim, Ali; McMahon, Colm; Hurson, Conor J.

    2017-01-01

    Revision hip arthroplasty requires comprehensive appreciation of abnormal bony anatomy. Advances in radiology and manufacturing technology have made three-dimensional (3D) representation of osseous anatomy obtainable, which provide visual and tactile feedback. Such life-size 3D models were manufactured from computed tomography scans of three hip joints in two patients. The first patient had undergone multiple previous hip arthroplasties for bilateral hip infections, resulting in right-sided pelvic discontinuity and a severe left-sided posterosuperior acetabular deficiency. The second patient had a first-stage revision for infection and recurrent dislocations. Specific metal reduction protocols were used to reduce artefact. The images were imported into Materialise MIMICS 14.12®. The models were manufactured using selective laser sintering. Accurate templating was performed preoperatively. Acetabular cup, augment, buttress, and cage sizes were trialled using the models, before being adjusted, and resterilised, enhancing the preoperative decision-making process. Screw trajectory simulation was carried out, reducing the risk of neurovascular injury. With 3D printing technology, complex pelvic deformities were better evaluated and treated with improved precision. Life-size models allowed accurate surgical simulation, thus improving anatomical appreciation and preoperative planning. The accuracy and cost-effectiveness of the technique should prove invaluable as a tool to aid clinical practice. PMID:28168060

  17. Treatment of acetabular chondral lesions with microfracture technique

    PubMed Central

    Mella, Claudio; Nuñez, Alvaro; Villalón, Ignacio

    2017-01-01

    Introduction: Acetabular cartilage lesions are frequently found during hip arthroscopy. In the hip joint they mostly occur secondary to a mechanical overload resulting from a pre-existing deformity as hip dysplasia or femoroacetabular impingement (FAI). Lesions identified during arthroscopy can vary greatly from the earliest stages to the most advanced (full-thickness lesions). These lesions occur in the acetabulum in the early stages of joint damage. Microfractures are indicated in full-thickness chondral defects. Ideally, these lesions must be focal and contained. Methods: The procedure begins debriding all the unstable chondral tissue of the lesion. The edges should have a net cut towards stable and healthy cartilage. It is recommended to make as many perforations as possible using arthroscopic awls. They should be ideally 4 mm deep and must have a vertical orientation to the surface. The suggested distance between perforations is of 3–4 mm. Once the treatment of the chondral lesion with the microfractures is complete, the labrum must be repaired. The repair of the labrum transforms in most of the cases the defect in a contained lesion containing better the clot in the lesion after the microfractures have been performed. It is also important to correct the bone deformity that has caused this lesion, which mostly corresponds to a “cam” deformity. Conclusion: Clinical studies confirm good short- and medium-term results in full-thickness chondral lesions treated with microfractures in the absence of osteoarthritis. However, it is difficult to determine if these results are only due to the microfractures, as this treatment is always complemented with several other factors and surgical procedures, such as labrum repair, correction of underlying bone deformity or change in postoperative activity of operated patients. PMID:28612705

  18. Welding torch gas cup extension

    NASA Technical Reports Server (NTRS)

    Gordon, Stephen S. (Inventor)

    1988-01-01

    The invention relates to a gas shielded electric arc welding torch having a detachable gas cup extension which may be of any desired configuration or length. The gas cup extension assembly is mounted on a standard electric welding torch gas cup to enable welding in areas with limited access. The gas cup assembly has an upper tubular insert that fits within the gas cup such that its lower portion protrudes thereform and has a lower tubular extension that is screwed into the lower portion. The extension has a rim to define the outer perimeter of the seat edge about its entrance opening so a gasket may be placed to effect an airtight seal between the gas cup and extension. The tubular extension may be made of metal or cermaic material that can be machined. The novelty lies in the use of an extension assembly for a standard gas cup of an electric arc welding torch which extension assembly is detachable permitting the use of a number of extensions which may be of different configurations and materials and yet fit the standard gas cup.

  19. Acetabular component navigation in lateral decubitus based on EOS imaging: A preliminary study of 13 cases.

    PubMed

    Billaud, A; Verdier, N; de Bartolo, R; Lavoinne, N; Chauveaux, D; Fabre, T

    2015-05-01

    Acetabular component navigation classically requires palpation of the bone landmarks defining the anterior pelvic plane (APP) (anterior superior iliac spine [ASIS] and pubis), the recording of which is not very reliable when performed in lateral decubitus. The objectives of the current experimental study were: (1) to assess the clinical feasibility of NAVEOS navigation (based on EOS imaging) in lateral decubitus; and (2) to compare precision versus classical APP-based navigation (NAVAPP). Iliac plane navigation using EOS is as reliable as APP navigation. A continuous prospective series of 13 total hip replacements were implanted in lateral decubitus under APP-guided navigation (NAVAPP). Planning used preoperative EOS measurement. The ASIS, pubis and ipsilateral posterior superior iliac spine (PSIS) were located and exported to the navigator. Intra-operatively, NAVEOS landmarks (acetabular center, ASIS and PSIS on the operated side) were palpated. Postoperatively, cup inclination and anteversion with respect to the APP were measured on EOS imaging (SterEOS3D software). The SterEOS3D measurements were compared to those of the performed NAVAPP and simulated NAVEOS navigations. Three patients were excluded for technical reasons. In the remaining 10, inclination on NAVAPP and SterEOS3D differed by a median 4° (range, 0-12°), and on NAVEOS versus SteEOS3D by 5° (range, 2-10°); anteversion on NAVAPP and SterEOS3D differed by a median 4.5° (range, 0-12°), and on NAVEOS versus SteEOS3D by 4° (range, 0-14°). Precision was comparable between NAVEOS and classical navigation. NAVEOS simplifies cup navigation in lateral decubitus on initial acquisition. These results require validation on a larger sample. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  20. Outcome and complications of constrained acetabular components.

    PubMed

    Yang, Cao; Goodman, Stuart B

    2009-02-01

    Constrained acetabular liners were developed for the surgical treatment of recurrent instability by holding the femoral head captive within the socket. This article summarizes the data describing constrained component designs, indications, outcome, and complications. Different designs accept head sizes of varying diameter and have differing amounts of rim elevation and offset, allowing slight variations in the range of movement allowed. Complications of constrained acetabular components can be divided into three categories. The first category is directly related to the constraining mechanism such as dislocation, head dissociation from the stem, liner dissociation from the acetabular device, and impingement with or without locking ring breakage. The second category is related to increased constraint such as aseptic component loosening and osteolysis and periprosthetic fracture. The third category includes those cases not associated with increased constraint such as infection, deep vein thrombosis, and periprosthetic fracture. This device is effective at achieving hip stability, but the complications related to the constraining mechanism and increased constraint are of concern. These devices should be used as a salvage measure for the treatment of severe instability.

  1. Importance of head diameter, clearance, and cup wall thickness in elastohydrodynamic lubrication analysis of metal-on-metal hip resurfacing prostheses.

    PubMed

    Liu, Feng; Jin, Zhongmin; Roberts, P; Grigoris, P

    2006-08-01

    The main design features of metal-on-metal (MOM) hip resurfacing prostheses in promoting elastohydrodynamic lubrication were investigated in the present study, including the femoral head diameter, the clearance, and the cup wall thickness. Simplified conceptual models were developed, based on equivalent uniform wall thicknesses for both the cup and the head as well as the support materials representing bone and cement, and subsequently used for elastohydrodynamic lubrication analysis. Both typical first- and second-generation MOM hip resurfacing prostheses with different clearances and cup wall thicknesses were considered with a fixed large bearing diameter of 50 mm, as well as a 28 mm diameter MOM total hip replacement bearing for the purpose of comparison. The importance of the head diameter and the clearance in promoting elastohydrodynamic lubrication was confirmed. Furthermore, it was also predicted that a relatively thin acetabular cup in the more recently introduced second-generation MOM hip resurfacing prostheses would be capable of improving elastohydrodynamic lubrication even further.

  2. The Epidemiology and Demographics of Hip Dysplasia

    PubMed Central

    Loder, Randall T.; Skopelja, Elaine N.

    2011-01-01

    The etiology of developmental dysplasia of the hip (DDH) is unknown. There are many insights, however, from epidemiologic/demographic information. A systematic medical literature review regarding DDH was performed. There is a predominance of left-sided (64.0%) and unilateral disease (63.4%). The incidence per 1000 live births ranges from 0.06 in Africans in Africa to 76.1 in Native Americans. There is significant variability in incidence within each racial group by geographic location. The incidence of clinical neonatal hip instability at birth ranges from 0.4 in Africans to 61.7 in Polish Caucasians. Predictors of DDH are breech presentation, positive family history, and gender (female). Children born premature, with low birth weights, or to multifetal pregnancies are somewhat protected from DDH. Certain HLA A, B, and D types demonstrate an increase in DDH. Chromosome 17q21 is strongly associated with DDH. Ligamentous laxity and abnormalities in collagen metabolism, estrogen metabolism, and pregnancy-associated pelvic instability are well-described associations with DDH. Many studies demonstrate an increase of DDH in the winter, both in the northern and southern hemispheres. Swaddling is strongly associated with DDH. Amniocentesis, premature labor, and massive radiation exposure may increase the risk of DDH. Associated conditions are congenital muscular torticollis and congenital foot deformities. The opposite hip is frequently abnormal when using rigorous radiographic assessments. The role of acetabular dysplasia and adult hip osteoarthritis is complex. Archeological studies demonstrate that the epidemiology of DDH may be changing. PMID:24977057

  3. Bone ingrowth around porous-coated acetabular implant: a three-dimensional finite element study using mechanoregulatory algorithm.

    PubMed

    Mukherjee, Kaushik; Gupta, Sanjay

    2016-04-01

    Fixation of uncemented implant is influenced by peri-prosthetic bone ingrowth, which is dependent on the mechanical environment of the implant-bone structure. The objective of the study is to gain an insight into the tissue differentiation around an acetabular component. A mapping framework has been developed to simulate appropriate mechanical environment in the three-dimensional microscale model, implement the mechanoregulatory tissue differentiation algorithm and subsequently assess spatial distribution of bone ingrowth around an acetabular component, quantitatively. The FE model of implanted pelvis subjected to eight static load cases during a normal walking cycle was first solved. Thereafter, a mapping algorithm has been employed to include the variations in implant-bone relative displacement and host bone material properties from the macroscale FE model of implanted pelvis to the microscale FE model of the beaded implant-bone interface. The evolutionary tissue differentiation was observed in each of the 13 microscale models corresponding to 13 acetabular regions. The total implant-bone relative displacements, averaged over each region of the acetabulum, were found to vary between 10 and 60 μm. Both the linear elastic and biphasic poroelastic models predicted similar mechanoregulatory peri-prosthetic tissue differentiation. Considerable variations in bone ingrowth (13-88%), interdigitation depth (0.2-0.82 mm) and average tissue Young's modulus (970-3430 MPa) were predicted around the acetabular cup. A progressive increase in the average Young's modulus, interdigitation depth and decrease in average radial strains of newly formed tissue layer were also observed. This scheme can be extended to investigate tissue differentiation for different surface texture designs on the implants.

  4. Late-presenting developmental dysplasia of the hip in Jordanian males

    PubMed Central

    Samarah, Omar Q.; Hadidi, Fadi A. Al; Hamdan, Mohammad Q.; Hantouly, Ashraf T.

    2016-01-01

    Objectives: To describe the pattern of developmental dysplasia of the hip (DDH) in late presenting Jordanian male patients and identify the risk factors and associated findings. Methods: This is a retrospective study of 1145 male patients who attended the Pediatric Orthopedic Clinic for a DDH check up. This study was carried out in the Orthopedic Section, Special Surgery Department, Faculty of Medicine, The University of Jordan, Amman, Jordan between March 2011 and October 2014. Data was collected from medical records, and x-ray measurements were evaluated. Results: Of the 1145 male patients, 43 (3.75%) with 70 involved hips were diagnosed with late- presenting DDH. Being a first-born baby resulted in 41.9% increased risk for DDH. Cesarian delivery was significantly associated with an increased risk of hip dislocation (p=0.004) while normal delivery was significantly associated with acetabular dysplasia (p=0.004). No predictable risk factors were found in 44.2% patients with DDH. Bilateral cases were more common than unilateral cases: (26 [60.5%] versus 17 [39.5%]). Limited abduction was a constant finding in all dislocated hips (p<0.001). Associated conditions, such as club foot and congenital muscular torticollis were not observed. Conclusion: Cesarian section is a significant risk for dislocated hips while normal delivery is significantly associated with acetabular dysplasia. Bilateral DDH is more common than the unilateral. Club foot and torticollis were not observed in this series. PMID:26837397

  5. Medium-term results of cementation of a highly cross-linked polyethylene liner into a well-fixed acetabular shell in revision hip arthroplasty.

    PubMed

    Lim, Seung-Jae; Lee, Keun-Ho; Park, Shin-Hyung; Park, Youn-Soo

    2014-03-01

    The present study was undertaken to document outcomes of cementation of a highly cross-linked polyethylene (PE) liner into a well-fixed acetabular metal shell in 36 hips. All operations were performed by a single surgeon using only one type of liner. Patients were followed for a mean of 6.1 years (range, 3-8 years). Mean Harris hip score improved from 58 points preoperatively to 91 points postoperatively. There were no cases of PE liner dislodgement or progressive osteolysis. 1 hip (2.8%) required revision surgery for acetabular cup loosening with greater trochanteric fracture. Complications included 1 peroneal nerve palsy and 1 dislocation. The results of this study and previous reports demonstrated that cementation of highly cross-linked PE liner into well-fixed metal shell could provide good midterm durability.

  6. Cervical Dysplasia: Is It Cancer?

    MedlinePlus

    ... showed cervical dysplasia. What does that mean? Is it cancer? Answers from Shannon K. Laughlin-Tommaso, M. ... or glandular cells. Dysplasia could go away on its own. Or, rarely, it could develop into cancer. ...

  7. Genetics Home Reference: craniometaphyseal dysplasia

    MedlinePlus

    ... Facebook Share on Twitter Your Guide to Understanding Genetic Conditions Search MENU Toggle navigation Home Page Search ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions craniometaphyseal dysplasia craniometaphyseal dysplasia Enable ...

  8. Genetics Home Reference: oculodentodigital dysplasia

    MedlinePlus

    ... particularly the eyes (oculo-), teeth (dento-), and fingers (digital). Common features in people with this condition are ... area? Other Names for This Condition oculo-dento-digital dysplasia oculo-dento-osseous dysplasia oculodentodigital syndrome oculodentoosseous ...

  9. Management of acetabular fractures in the geriatric patient

    PubMed Central

    Hanschen, Marc; Pesch, Sebastian; Huber-Wagner, Stefan; Biberthaler, Peter

    2017-01-01

    Introduction: Open reduction and internal fixation (ORIF) is standard care for most acetabular fractures. With increasing numbers of acetabular fractures in the elderly, the risk of revision surgery and conversion to total hip replacement (THR) is increasing. Alarmingly, about 20–25% of acetabular fractures in the elderly following ORIF needed revision and conversion to delayed THR. Methods: Recently, prognostic factors have been identified, which correlate with an increased risk of worse outcomes following ORIF of acetabular fractures in the elderly patient. Patient risk factors include, for example, age, comorbidities, and degree of osteoporosis. Injury risk factors mainly include the fracture pattern. Results: The concept of primary THR following acetabular fractures is an alternative to ORIF, especially in the elderly patient. Satisfactory outcomes have been reported in different studies for primary THR following acetabular fractures in the elderly. The surgeon should be aware of strict selection criteria in order to achieve these satisfactory outcomes. Therefore, an individualized treatment plan has to be defined for elderly patients following acetabular fractures. Discussion: Here, the advantages and disadvantages of ORIF versus THR following acetabular fractures in the elderly are discussed. PMID:28534471

  10. Optic atrophy and glaucomatous cupping.

    PubMed

    Radius, R L; Maumenee, A E

    1978-02-01

    We reviewed 170 eyes of 112 patients with optic atrophy from various causes. Special attention was directed towards measured cup:disk ratios as well as presence of glaucomatous-like cupping of the optic nerve head. We observed a small but significant increase in nerve head cupping in eyes with optic atrophy when compared to contralateral eyes, as well as to eyes of 50 diabetic patients. No characteristic glaucomatous disk changes were documented. We evaluated these findings with respect to possible causes of glaucomatous disk and field changes.

  11. Early postoperative acetabular discontinuity after total hip arthroplasty.

    PubMed

    Desai, Gaurav; Ries, Michael D

    2011-12-01

    Periprosthetic acetabular fracture is a rare complication after total hip arthroplasty (THA). However, we have treated 2 patients with acute postoperative acetabular discontinuity that occurred 2 and 3 weeks after primary THA. Both fractures were in elderly osteoporotic female patients with minimal trauma and may have developed from unrecognized intraoperative fractures. Pelvic stability was restored with acetabular revision using medial morselized bone grafting and a cemented reconstruction cage. This report demonstrates that early postoperative periprosthetic acetabular discontinuity after THA is a risk in elderly patients with severe osteoporosis and that salvage of acetabular fixation can be achieved with cemented cage reconstruction and medial morselized bone grafting. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Developmental Dysplasia of the Hip

    MedlinePlus

    ... to 2-Year-Old Developmental Dysplasia of the Hip KidsHealth > For Parents > Developmental Dysplasia of the Hip A A A What's in this article? What ... Symptoms Diagnosis Treatment Outlook Developmental dysplasia of the hip (DDH) is a problem with the way a ...

  13. Complications associated with the Bernese periacetabular osteotomy for hip dysplasia in adolescents.

    PubMed

    Thawrani, Dinesh; Sucato, Daniel J; Podeszwa, David A; DeLaRocha, Adriana

    2010-07-21

    The Bernese (Ganz) periacetabular osteotomy is an effective surgical procedure to reorient the acetabulum, allowing restoration of anatomic femoral head coverage and medial translation of the hip in adults with hip dysplasia. However, it is a challenging surgical procedure, and we know of no study that has specifically analyzed the complications and associated factors seen with this procedure in adolescent patients. A retrospective clinical and radiographic review of a consecutive series of adolescent patients who underwent a Bernese periacetabular osteotomy for hip dysplasia was conducted. Eighty-three osteotomies were performed in seventy-six patients with an average age (and standard deviation) of 15.6 +/- 2.4 years. Significant improvement from the preoperative to the two-year follow-up evaluation was seen radiographically with regard to the lateral center-edge angle (-0.14 degrees to 35.5 degrees), the ventral center-edge angle (-5.13 degrees to 31.3 degrees), and the femoral head extrusion index (38.4% to 7.7%) (p < 0.0001 for all). There were three major complications, including excessive arterial bleeding requiring embolization in a patient with a prior acetabuloplasty, osteonecrosis of the acetabular fragment in a patient with severe dysplasia and subluxation of the hip, and osteonecrosis of the femoral head following combined periacetabular and femoral osteotomies in a patient with Charcot-Marie-Tooth disease. Eighteen hips (22%) had minor complications, including nonunion of the superior pubic ramus osteotomy (five hips), a superficial stitch abscess (four), and transient lateral femoral cutaneous nerve palsy (four). Nine hips (11%) underwent removal of symptomatic screws, and two required a second operation to reposition the acetabular fragment. An underlying diagnosis other than developmental dysplasia increased the prevalence of minor complications (p = 0.0017), while a major complication was more likely with longer surgery time, greater blood loss

  14. Two-year radiologic assessment of the Trident Peripheral Self-Locking cup using EBRA.

    PubMed

    Nunag, Perrico; Deakin, Angela H; Oburu, Ezekiel; Sarungi, Martin

    2012-01-01

    We performed a radiologic assessment of the Trident Peripheral Self-Locking cup 2 years after implantation to assess early migration behaviour and to establish if incomplete postoperative seating correlated with early instability. A retrospective analysis of 30 cases was performed using EBRA. No cups had acetabular screws. Average total migration was 1.5 mm (range 0.1 to 5.9 mm). Seventeen showed total migration >1 mm and 7 of these showed further migration >2 mm (range 2.3 to 5.9 mm). Twenty cups demonstrated incomplete seating on initial post-operative radiographs (mean 1.4 mm, range 0.3 to 3.0). No relationship between incomplete seating and migration was identified (p = 0.86). The majority of gaps consolidated at differing times within the 2 year period. Oxford Hip scores showed significant improvement after surgery (p = 0.001) and this was independent of migration (p = 0.76). At 5 years there were no revisions for aseptic loosening. The majority of the cups demonstrated early radiographic instability, and this was not related to incomplete seating. Five year functional outcome appears good and independent of migration and initial seating.

  15. On Cup Anemometer Rotor Aerodynamics

    PubMed Central

    Pindado, Santiago; Pérez, Javier; Avila-Sanchez, Sergio

    2012-01-01

    The influence of anemometer rotor shape parameters, such as the cups' front area or their center rotation radius on the anemometer's performance was analyzed. This analysis was based on calibrations performed on two different anemometers (one based on magnet system output signal, and the other one based on an opto-electronic system output signal), tested with 21 different rotors. The results were compared to the ones resulting from classical analytical models. The results clearly showed a linear dependency of both calibration constants, the slope and the offset, on the cups' center rotation radius, the influence of the front area of the cups also being observed. The analytical model of Kondo et al. was proved to be accurate if it is based on precise data related to the aerodynamic behavior of a rotor's cup. PMID:22778638

  16. On cup anemometer rotor aerodynamics.

    PubMed

    Pindado, Santiago; Pérez, Javier; Avila-Sanchez, Sergio

    2012-01-01

    The influence of anemometer rotor shape parameters, such as the cups' front area or their center rotation radius on the anemometer's performance was analyzed. This analysis was based on calibrations performed on two different anemometers (one based on magnet system output signal, and the other one based on an opto-electronic system output signal), tested with 21 different rotors. The results were compared to the ones resulting from classical analytical models. The results clearly showed a linear dependency of both calibration constants, the slope and the offset, on the cups' center rotation radius, the influence of the front area of the cups also being observed. The analytical model of Kondo et al. was proved to be accurate if it is based on precise data related to the aerodynamic behavior of a rotor's cup.

  17. Controversies in Treatment of Acetabular Fracture

    PubMed Central

    Grubor, Predrag; Krupic, Ferid; Biscevic, Mirza; Grubor, Milan

    2015-01-01

    Introduction: Acetabular fractures treatment represents a great controversy, challenge and dilemma for an orthopedic surgeon. Aim: The aim of the paper was to present the results of treatment of 96 acetabular fractures in the Clinic of Traumatology Banja Luka, in the period from 2003 to 2013, as well as to raise awareness regarding the controversy in the methods of choice in treating acetabulum fractures. Material and methods: The series consists of 96 patients, 82 males and 14 females, average age 40.5 years. Traffic trauma was the cause of fractures in 79 patients (85%), and in 17 patients (15%) fractures occurred due to falls from height. Polytrauma was present in 31 patients (32%). According to the classification of Judet and Letournel, representation of acetabular fractures was as follows: posterior wall in 32 patients, posterior column in 28, anterior wall in 4, anterior column in 2, transverse fractures in 8, posterior wall and posterior column in 10, anterior and posterior wall in 6, both- column in 4 and transversal fracture and posterior wall in 2 patients. 14 patients were treated with traction, that is, 6 patients with femoral traction and 8 patients with both lateral and femoral traction. 82 patients (86.4%) were surgically treated. Kocher-Langenbeck approach was applied in the treatment of 78 patients. In two patients from the Kocher-Langenbeck’s approach, the Ollier’s approach had to be applied as well. Two acetabular were primarily treated with Ollier’s approach. Extended Smith- Peterson’s approach was applied 4 times, and Emile Letournel’s (ilioinguinal) approach 14 times. Results: Functional outcome (after follow-up of 18 months), according to the Harris hip score of surgical treatment in 82 patients, was as follows: good 46 (56%), satisfactory 32 (39%) and poor 4 (5%). Results of acetabulum fractures treated with traction were: good 8 (57%), satisfactory 4 (28%) and poor 2 (15%). According to the Brook’s classification of heterotopic

  18. [Ovarian epithelial dysplasia: Description of a dysplasia scoring scheme].

    PubMed

    Chene, Gautier; Dauplat, Jacques; Raoelfils, Ines; Bignon, Yves-Jean; Cayre, Anne; Jaffeux, Patricia; Aublet-Cuvelier, Bruno; Pomel, Christophe; Penault-Llorca, Frédérique

    2011-02-01

    Precancerous ovarian epithelial dysplasia was first described after prophylactic oophorectomy (OP) for genetic risk (BRCA mutation) or because of a strong family history of ovarian and/or breast cancer. The objective of this study was to describe histopathological features of ovarian dysplasia and to propose a dysplasia scoring sheme with a cut-off. One hundred and twenty-five bilateral oophorectomies (genetic predisposition: n=35 and control group: n=90) were reviewed by two pathologists blinded to clinical data. Eleven epithelial cytological and architectural features were studied and an ovarian dysplasia score was defined to compare the degree of ovarian epithelial abnormalities between the two groups. Mean ovarian dysplasia score was significantly higher in prophylactic oophorectomy group than in control group (9.0 versus 3.5, P<0.001). Dysplasia was more severe in OP with BRCA mutation than in OP without (11.6 in BRCA 1; 7.6 in BCRA 2; 7.1 in family history). The cut off for dysplasia was 8 with a sensitivity of 60% and a specificity of 93.3%. The increased dysplasia score in OP and the gradation in dysplastic severity in OP with proven BRCA mutations may suggest that ovarian dysplasia could be a pre-malignant non invasive histopathological lesion. The 11 cytological and architectural features in the dysplasia scoring sheme could be a useful tool to study ovarian dysplasia. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  19. Aerodynamic characteristics of anemometer cups

    NASA Technical Reports Server (NTRS)

    Brevoort, M J; Joyner, U T

    1934-01-01

    The static lift and drag forces on three hemispherical and two conical cups were measured over a range of angles of attack from 0 degrees to 180 degrees and a range of Reynolds Numbers from very small up to 400,000. The problems of supporting the cup for measurement and the effect of turbulence were also studied. The results were compared with those of other investigators.

  20. Open Science- Space Coffee Cup

    NASA Image and Video Library

    2016-10-11

    In low-gravity environments like the space station, fluids tend to get ‘sticky.’ Surface tension and capillary effects, which are overwhelmed by gravity on Earth, rule the day in space. As a result, coffee tends to cling to the walls of the cup. The zero-G coffee cup solves these problems by 'going with the flow': putting the strange behavior of fluid in microgravity to work.

  1. The influence of friction and interference on the seating of a hemispherical press-fit cup: a finite element investigation.

    PubMed

    Spears, I R; Morlock, M M; Pfleiderer, M; Schneider, E; Hille, E

    1999-11-01

    The formation of gaps in the polar region of acetabular cups is seen as a drawback of press-fit fixation of non-cemented acetabular cups. Recent findings indicate a link between long-term polar gaps and the gaps present directly after implantation. In this study the process of press-fitting is simulated with a linear-elastic two-dimensional axisymmetric finite-element model. The aim of this paper is to investigate the possible importance of friction and interference on the formation of these gaps. A range of cup-bone friction coefficients (mu = 0.1-0.5) is assigned to the cup-bone interface in order to represent the unknown amount of friction occurring during press-fitting. The cup is modeled with a radius of 27 mm, whereas the radius of the cavity is varied between 26.50 and 26.75 mm, thus, creating 0.50 and 0.25 mm radial interference fits. The difference in cavity radius represents the discrepancy between the radius of the last-reamer-used and radius of the cavity it creates. The subchondral plate is considered as being completely removed during reaming. The effects of impact blows via the surgeon's mallet during surgery are modeled as a series of four load pulses, in which peak force is gradually increased from 0.5 to 4.0 kN. The effects of load removal as well as those of load application are investigated. On load application, the cup penetrates into the cavity, and on load removal, the cup rebounds. Depending on the friction, interference and load applied, the position of the cup after the load pulse is somewhere between its position at peak force and its position at the beginning of the pulse. Although the simplifications and conditions involved in the creation of the model necessitate caution when interpreting the results for all clinical cases, it is found that the seating of hemispherical cups in trabecular bone could be more satisfactory for intermediate values of friction (mu = 0.2-0.3) and smaller interference fits (0.25 mm).

  2. Bernese periacetabular osteotomy for hip dysplasia: Surgical technique and indications

    PubMed Central

    Kamath, Atul F

    2016-01-01

    For young, active patients with healthy hip cartilage, pelvic osteotomy is a surgical option in to address hip pain and to improve mechanical loading conditions related to dysplasia. Hip dysplasia may lead to arthrosis at an early age due to poor coverage of the femoral head and abnormal loading of the joint articulation. In patients with symptomatic dysplasia and closed triradiate cartilage (generally over age 10), including adolescents and young adults (generally up to around age 40), the Bernese periacetabular osteotomy (PAO) is a durable technique for addressing underlying structural deformity. The PAO involves a modified Smith-Petersen approach. Advantages of the Bernese osteotomy include preservation of the weight-bearing posterior column of the hemi-pelvis, preservation of the acetabular blood supply, maintenance of the hip abductor musculature, and the ability to effect powerful deformity correction about an ideal center of rotation. There is an increasing body of evidence that preservation of the native hip can be improved through pelvic osteotomy. In contrast to hip osteotomy and joint preservation, the role of total hip arthroplasty in young, active patients with correctable hip deformity remains controversial. Moreover, the durability of hip replacement in young patients is inherently limited. Pelvic osteotomy should be considered the preferred method to address correctable structural deformity of the hip in the young, active patient with developmental dysplasia. The Bernese PAO is technically demanding, yet offers reproducible results with good long-term survivorship in carefully selected patients with preserved cartilage and the ability to meet the demands of rehabilitation. PMID:27190755

  3. Triple pelvic osteotomy in the treatment of hip dysplasia.

    PubMed

    Vukasinović, Zoran; Spasovski, Dusko; Zivković, Zorica; Slavković, Nemanja; Cerović, Sofija

    2009-01-01

    Insufficient femoral head coverage is found in a variety of diseases, with acetabular dysplasia as the most frequent disorder and triple pelvic osteotomy as the most recently introduced surgical treatment. This study analyses pre- and postoperative pathoanatomic characteristics of triple in comparison to Salter and Chiari osteotomies, with a logistic regression analysis of outcome predictor and effect explanator factors in relation to the chosen type of operation. The study involved 136 adolescents treated with Salter and Chiari osteotomies or a triple pelvic osteotomy at the Institute of Orthopaedic Surgery "Banjica" in Belgrade. The patients were between 10-20 years old at the time of operation. We collected and analyzed data from all the patients: illness history, operative parameters, preoperative and postoperative pathoanatomic data. The data was statistically processed using the statistical software SPSS, defining standard descriptive values, and by using the appropriate tests of analytic statistics: t-test for dependent and independent variables, chi2-test, Fisher's exact test, Wilcoxon's test, parameter correlation, one-way ANOVA, multi-factorial ANOVA and logistic regression, according to the type of the analyzed data and the conditions under which the statistical methods were applied. The average CE angle after triple pelvic osteotomy was 43.5 degrees, more improved than after the Salter osteotomy (33.0 degrees) and Chiari osteotomy (31.4 degrees) (F = 16.822; p < 0.01). Postoperative spherical congruence was also more frequent after the triple osteotomy than after the other two types of operations, and with a high significance. Preoperative painful discomfort was found to be a valid predictor of indications for the triple osteotomy over both Chiari and Salter osteotomies. The valid explanators of effect for the triple osteotomy are: postoperative joint congruence (compared to the Chiari osteotomy) and increase in joint coverage (compared to Salter

  4. [Modular reconstruction in acetabular revision with antiprotrusio cages and metal augments : the cage-and-augment system].

    PubMed

    Günther, K-P; Wegner, T; Kirschner, S; Hartmann, A

    2014-04-01

    Restore primary center of rotation and reconstruct extensive bone defects in hip revision surgery with a modular off-label implant combined with antiprotrusion cage and metal augment, thus, achieving improved hip function. Large segmental acetabular defects with nonsupportive columns (Paprosky type 3a and 3b) in cup loosening or Girdlestone situation. In case of pelvic discontinuity posterior column-plating is possible. Persisting hip infection and severe systemic disorders impairing achievement of secondary stability through bony integration of metal augment. Posterolateral (if dorsal column plating) or other approach. Remove loose implant and granulation tissue with sufficient exposure of bleeding bone. Size acetabular defect with trial components of augment and appropriate antiprotrusio cage. Fixation of selected metal augment with screws. Fill additional acetabular defects with morsellized bone graft. Open a slot into the ischium to fix the distal flange of the cage. If necessary, bend both flanges according to patient's anatomy. Enter the ischium with distal flange and gradual impaction of the antiprotrusio ring. Final stabilization of the ring with several screws aiming at the posterior column or the acetabular dome. Inject cement between ring and augment to stabilize the construction and avoid metal wear. Final cement fixation of a polyethylene liner or a dual-mobility cup into the antiprotrusio ring. In pelvic discontinuity with major instability osteosynthesis of the dorsal column can be performed prior to cementation. Prophylaxis of periprosthetic infection, DVT and heterotopic ossification. Physical therapy with partial weight bearing (20 kp) for 6 weeks; in discontinuity initial wheel chair mobilization. Since 2008, 72 off-label implantations of a combined antiprotrusio cage and a Trabecular Metal™ Augment were performed. A total of 44 patients (46 operations) were investigated at 38.8 (36-51) months postoperatively. In all, 36 patients had a

  5. Spoon-to-Cup Fading as Treatment for Cup Drinking in a Child with Intestinal Failure

    ERIC Educational Resources Information Center

    Groff, Rebecca A.; Piazza, Cathleen C.; Zeleny, Jason R.; Dempsey, Jack R.

    2011-01-01

    We treated a child with intestinal failure who consumed solids on a spoon but not liquids from a cup. We used spoon-to-cup fading, which consisted of taping a spoon to a cup and then gradually moving the bowl of the spoon closer to the edge of the cup. Spoon-to-cup fading was effective for increasing consumption of liquids from a cup. (Contains 2…

  6. World Cup Final

    NASA Technical Reports Server (NTRS)

    2006-01-01

    On July 9, hundreds of millions of fans worldwide will be glued to their television sets watching the final match of the 2006 FIFA World Cup, played in Berlin's Olympic stadium (Olympiastadion). The stadium was originally built for the 1936 Summer Olympics. The Olympic Stadium seats 76,000,; its roof rises 68 meters over the seats and is made up of transparent panels that allow sunlight to stream in during the day.

    With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

    Size: 12.1 by 15.9 kilometers (7.5 by 9.5 miles) Location: 52.5 degrees North latitude, 13.3 degrees East longitude Orientation: North at top Image Data: ASTER bands 3, 2, and 1 Original Data Resolution: 15 meters (49.2 feet) Dates Acquired: October 15, 2005

  7. World Cup Final

    NASA Technical Reports Server (NTRS)

    2006-01-01

    On July 9, hundreds of millions of fans worldwide will be glued to their television sets watching the final match of the 2006 FIFA World Cup, played in Berlin's Olympic stadium (Olympiastadion). The stadium was originally built for the 1936 Summer Olympics. The Olympic Stadium seats 76,000,; its roof rises 68 meters over the seats and is made up of transparent panels that allow sunlight to stream in during the day.

    With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

    Size: 12.1 by 15.9 kilometers (7.5 by 9.5 miles) Location: 52.5 degrees North latitude, 13.3 degrees East longitude Orientation: North at top Image Data: ASTER bands 3, 2, and 1 Original Data Resolution: 15 meters (49.2 feet) Dates Acquired: October 15, 2005

  8. Comparison of clinical, radiographic, computed tomographic, and magnetic resonance imaging methods for early prediction of canine hip laxity and dysplasia.

    PubMed

    Ginja, Mário M D; Ferreira, António J; Jesus, Sandra S; Melo-Pinto, Pedro; Bulas-Cruz, José; Orden, Maria A; San-Roman, Fidel; Llorens-Pena, Maria P; Gonzalo-Orden, José M

    2009-01-01

    The purpose of the study was to use two palpation methods (Bardens and Ortolani), a radiographic distraction view, three computed tomography (CT) measurements (dorsolateral subluxation score, the lateral center-edge angle, and acetabular ventroversion angle) and two magnetic resonance (MR) imaging hip studies (synovial fluid and acetabular depth indices) in the early monitoring of hip morphology and laxity in 7-9 week old puppies; and in a follow-up study to compare their accuracy in predicting later hip laxity and dysplasia. The MR imaging study was performed with the dog in dorsal recumbency and the CT study with the animal in a weight-bearing position. There was no association between clinical laxity with later hip laxity or dysplasia. The dorsolateral subluxation score and the lateral center-edge angle were characterized by a weak negative correlation with later radiographic passive hip laxity (-0.26 < r < -0.38, P < 0.05) but its association with hip dysplasia was not significant. There was an association between early radiographic passive hip laxity and synovial fluid index with later passive hip laxity (0.41 < r < 0.55, P < 0.05) and this was significantly different in dysplastic vs. nondysplastic hips (P < 0.05). There was no association between the remaining variables and later hip laxity or dysplasia. The overlapping ranges of early passive hip laxity and synovial fluid index for hip dysplasia grades and the moderate correlations with the later passive hip laxity make the results of these variables unreliable for use in predicting hip laxity and dysplasia susceptibility.

  9. A Newly Recognized Syndrome With Characteristic Facial Features, Skeletal Dysplasia, and Developmental Delay

    PubMed Central

    Baratela, Wagner A.R.; Bober, Michael B.; Tiller, George E.; Okenfuss, Ericka; Ditro, Colleen; Duker, Angela; Krakow, Deborah; Stabley, Deborah L.; Sol-Church, Katia; Mackenzie, William; Lachman, Ralph; Scott, Charles I.

    2014-01-01

    We describe a series of seven male patients from six different families with skeletal dysplasia, characteristic facial features, and developmental delay. Skeletal findings include patellar dislocation, short tubular bones, mild metaphyseal changes, brachymetacarpalia with stub thumbs, short femoral necks, shallow acetabular roofs, and platyspondyly. Facial features include: a flattened midface with broad nasal bridge, cleft palate or bifid uvula and synophrys. All of the patients demonstrated pre-school onset of a cognitive developmental delay with a shortened attention span. Some of the cognitive delay was masked by a warm and engaging personality. We posit that these individuals have a newly recognized syndrome characterized by the described features. There is some phenotypic overlap between these patients and Desbuquois dysplasia; however molecular testing demonstrated that this is a distinct disorder. Given the family information available for each patient, we are suspicious that the constellation of findings reported herein could be an X-linked recessive syndrome. PMID:22711505

  10. Comparative Study of Peripheral Rim Fixation Using Jumbo Cup in Revisional Hip Arthroplasty

    PubMed Central

    Jo, Woo-Lam; Im, Jin-Hyung; Kim, Seung-Chan; Kwon, Soon-Yong; Kim, Yong-Sik

    2017-01-01

    Purpose It is challenging procedure to revise acetabular component in acetabulum with severe bone defect or deformity. The jumbo cup is good option for revisional arthroplasty in large bone defect. The purpose of this study is to compare the prognosis of revisional total hip arthroplasty using jumbo cup with peripheral rim fixation and no rim fixation. Materials and Methods We included the patients who had performed acetabular revisional total hip arthroplasty from January 2002 to March 2015 in our institute. Total of 51 hips (51 patients) were included. The mean follow up period was 51 months (range, 12 to 154 months) and mean age was 60.7 years (range, 30 to 81 years). We divided into two groups (peripheral rim fixation group and no rim fixation group) by anteroposterior and lateral plain radiograph. We compared survival rate, hip center change and clinical outcomes between two groups. Results There were 37 patients in peripheral rim fixation group and 14 patients in no rim fixation group. There was one patient who had aseptic loosening necessary to re-revision in rim fixation group and 3 patients in no rim fixation group. And one patient had superficial infection in rim fixation group and one patient had periprosthetic fracture in no rim fixation group. Survival rate was higher in the peripheral rim fixation group (97.3%) than no rim fixation group (78.6%, P=0.028) Conclusion Based on our findings, peripheral rim fixation might be recommended to improve short-term outcome after revision total hip arthroplasty using jumbo cup. PMID:28316959

  11. Bone remodeling around the Cambridge cup: a DEXA study of 50 hips over 2 years.

    PubMed

    Field, Richard E; Cronin, Michael D; Singh, Parminder J; Burtenshaw, Christine; Rushton, Neil

    2006-10-01

    In a prospective 2-year study we have used dual-energy X-ray absorptiometry to measure periprosthetic bone mineral density (BMD) following implantation of a novel, "physiological", acetabular component designed using composite materials. The acetabular components were implanted in hydroxyapatite (HA) and HA-removed options. They were implanted in conjunction with a cemented femoral component in 50 female patients who presented with displaced, subcapital, fractures of the neck of the femur. Regions of interest (ROI) were defined according to De Lee and Charnley. BMD during follow-up was compared with immediate postoperative values for the affected limb. The mean precision error (CV%) was 1.01%, 2.26% and 1.12%, for ROI I, II and III respectively. The mean change in BMD, for both cups, was analyzed. There was no significant difference between the BMD changes induced with the HA- and non-HA-coated cups. After an initial fall in BMD in all 3 ROI at 6 months, ROI I and ROI II showed return to baseline BMD by 2 years. ROI III showed no significant decrease in BMD beyond 6 months, but did not return to baseline levels. Statistical analysis revealed no significant decrease in BMD in ROI I and ROI II at 2 years, compared with immediate postoperative values. The changes in BMD reflect a pattern of maximally reduced stress in the non-weight-bearing zone (ROI III), with preservation of bone density in weight bearing zones ROI I and ROI II. These results support the design principles of the Cambridge cup.

  12. Effects of normal and abnormal loading conditions on morphogenesis of the prenatal hip joint: application to hip dysplasia

    PubMed Central

    Giorgi, Mario; Carriero, Alessandra; Shefelbine, Sandra J.; Nowlan, Niamh C.

    2015-01-01

    Joint morphogenesis is an important phase of prenatal joint development during which the opposing cartilaginous rudiments acquire their reciprocal and interlocking shapes. At an early stage of development, the prenatal hip joint is formed of a deep acetabular cavity that almost totally encloses the head. By the time of birth, the acetabulum has become shallower and the femoral head has lost substantial sphericity, reducing joint coverage and stability. In this study, we use a dynamic mechanobiological simulation to explore the effects of normal (symmetric), reduced and abnormal (asymmetric) prenatal movements on hip joint shape, to understand their importance for postnatal skeletal malformations such as developmental dysplasia of the hip (DDH). We successfully predict the physiological trends of decreasing sphericity and acetabular coverage of the femoral head during fetal development. We show that a full range of symmetric movements helps to maintain some of the acetabular depth and femoral head sphericity, while reduced or absent movements can lead to decreased sphericity and acetabular coverage of the femoral head. When an abnormal movement pattern was applied, a deformed joint shape was predicted, with an opened asymmetric acetabulum and the onset of a malformed femoral head. This study provides evidence for the importance of fetal movements in the prevention and manifestation of congenital musculoskeletal disorders such as DDH. PMID:26163754

  13. Effects of normal and abnormal loading conditions on morphogenesis of the prenatal hip joint: application to hip dysplasia.

    PubMed

    Giorgi, Mario; Carriero, Alessandra; Shefelbine, Sandra J; Nowlan, Niamh C

    2015-09-18

    Joint morphogenesis is an important phase of prenatal joint development during which the opposing cartilaginous rudiments acquire their reciprocal and interlocking shapes. At an early stage of development, the prenatal hip joint is formed of a deep acetabular cavity that almost totally encloses the head. By the time of birth, the acetabulum has become shallower and the femoral head has lost substantial sphericity, reducing joint coverage and stability. In this study, we use a dynamic mechanobiological simulation to explore the effects of normal (symmetric), reduced and abnormal (asymmetric) prenatal movements on hip joint shape, to understand their importance for postnatal skeletal malformations such as developmental dysplasia of the hip (DDH). We successfully predict the physiological trends of decreasing sphericity and acetabular coverage of the femoral head during fetal development. We show that a full range of symmetric movements helps to maintain some of the acetabular depth and femoral head sphericity, while reduced or absent movements can lead to decreased sphericity and acetabular coverage of the femoral head. When an abnormal movement pattern was applied, a deformed joint shape was predicted, with an opened asymmetric acetabulum and the onset of a malformed femoral head. This study provides evidence for the importance of fetal movements in the prevention and manifestation of congenital musculoskeletal disorders such as DDH.

  14. Can A Cup Anemometer `Underspeed'?

    NASA Astrophysics Data System (ADS)

    Kristensen, L.

    An analysis of cup-anemometer dynamics has been carried out inorder to determine whether the mean-wind velocity can have anegative bias. This would be contrary to the general belief thatcup anemometers always overspeed. Compared to prior analyses, theeffect of a possible nonlinearity of the calibration function isincluded. The conclusion is that neither longitudinal nor lateralvelocity fluctuations can contribute significantly to a negativebias. However, if a cup anemometer has an angular response thatfalls below the ideal cosine response, there will, as demonstratedin the concluding discussion, be a negative contribution from thevertical velocity fluctuations to the total bias, and thiscontribution may even outbalance the positive contributions fromthe longitudinal velocity fluctuations. Concrete evidence of suchexotic cup anemometer behaviour has not been reported in theliterature.

  15. Cemented total hip arthroplasty following acetabular fracture.

    PubMed

    Scott, C E H; MacDonald, D; Moran, M; White, T O; Patton, J T; Keating, J F

    2017-10-01

    To evaluate the outcomes of cemented total hip arthroplasty (THA) following a fracture of the acetabulum, with evaluation of risk factors and comparison with a patient group with no history of fracture. Between 1992 and 2016, 49 patients (33 male) with mean age of 57 years (25 to 87) underwent cemented THA at a mean of 6.5 years (0.1 to 25) following acetabular fracture. A total of 38 had undergone surgical fixation and 11 had been treated non-operatively; 13 patients died at a mean of 10.2 years after THA (0.6 to 19). Patients were assessed pre-operatively, at one year and at final follow-up (mean 9.1 years, 0.5 to 23) using the Oxford Hip Score (OHS). Implant survivorship was assessed. An age and gender-matched cohort of THAs performed for non-traumatic osteoarthritis (OA) or avascular necrosis (AVN) (n = 98) were used to compare complications and patient-reported outcome measures (PROMs). The mean time from fracture to THA was significantly shorter for patients with AVN (2.2 years) or protrusio (2.2 years) than those with post-traumatic OA (9.4 years) or infection (8.0 years) (p = 0.03). Nine contained and four uncontained defects were managed with autograft (n = 11), bulk allograft (n = 1), or trabecular metal augment (n = 1). Initial fracture management (open reduction and internal fixation or non-operative), timing of THA (>/< one year), and age (>/< 55 years) had no significant effect on OHS or ten-year survival. Six THAs were revised at mean of 12 years (5 to 23) with ten-year all-cause survival of 92% (95% confidence interval 80.8 to 100). THA complication rates (all complications, heterotopic ossification, leg length discrepancy > 10 mm) were significantly higher following acetabular fracture compared with atraumatic OA/AVN and OHSs were inferior: one-year OHS (35.7 versus 40.2, p = 0.026); and final follow-up OHS (33.6 versus 40.9, p = 0.008). Cemented THA is a reasonable option for the sequelae of acetabular fracture. Higher complication rates and

  16. Residual hip dysplasia at 1 year after treatment for neonatal hip instability is not related to degenerative joint disease in young adulthood: a 21-year follow-up study including dGEMRIC.

    PubMed

    Wenger, D; Siversson, C; Dahlberg, L E; Tiderius, C J

    2016-03-01

    Developmental dysplasia of the hip (DDH) is associated with an increased risk of early hip osteoarthritis (OA). We aimed to examine the outcome at the completion of growth in a cohort of children who had residual acetabular dysplasia at age 1 year following early treatment for neonatal instability of the hip (NIH). We examined 21 of 30 subjects who had been treated with the von Rosen splint neonatally for NIH and had residual acetabular dysplasia at age 1 year. Mean follow-up time was 21 years (range 17-24). Signs of OA and acetabular dysplasia were assessed by radiography. Cartilage quality was assessed by delayed Gadolinium Enhanced Magnetic Resonance Imaging of Cartilage (dGEMRIC), a tool for molecular imaging of cartilage quality, at 1.5 T. Patient reported outcome (PRO) was assessed by the 12-item WOMAC score. No study participant had radiographic OA (defined as Kellgren-Lawrence grade ≥2) or minimum joint space width (JSW) ≤2 mm. The mean dGEMRIC index was 630 ms (95% CI: 600-666, range: 516-825) suggesting good cartilage quality. The mean 12-item WOMAC score was 1.2. Two of three radiographic measurements of DDH correlated positively to the dGEMRIC index. Children treated neonatally for NIH have good hip function and no signs of cartilage degeneration at 21-year follow-up, despite residual dysplasia at age 1 year. Unexpectedly, radiographic signs of dysplasia were associated with better cartilage quality, as assessed with dGEMRIC. This may indicate cartilage adaptation to increased mechanical stress in mild hip dysplasia. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  17. [Craniofacial fibrous dysplasia].

    PubMed

    Couturier, A; Aumaître, O; Mom, T; Gilain, L; André, M

    2016-12-01

    Fibrous dysplasia of bone is a benign, uncommon, sporadic, congenital skeletal disorder resulting in deformity. This disease arises from activating somatic mutation in GNAS which encodes the α subunit of the G stimulatory protein associated with proliferation of undifferentiated osteogenic cells resulting in marrow fibrosis, abnormal matrix production, and stimulation of osteoclastic resorption upon overproduction of IL-6 observed in dysplastic cells. Fibrous dysplasia may be monostotic or polyostotic. This mutation affecting many tissues, café au lait skin macules and endocrinopathies (precocious puberty, hyperthyroidism, growth hormone excess, Cushing syndrome) may be associated in McCune-Albright syndrome, but also myxoma in Mazabraud syndrome or phosphate diabetes. Diagnosis of craniofacial fibrous dysplasia should be considered in the presence of headache, neuralgia, sensory disorders (vision, hearing, balance, smelling), functional disorders (nasal obstruction, nasolacrimal duct obstruction, non-matching occlusion), infectious complications (sinusitis, otitis, mastoiditis). Such symptoms should lead to perform craniofacial CT scan completed with MRI. Bone biopsy is not systematic. Surgical treatment is discussed in cases of nervous complication, facial deformity or active lesions. In case of pain resistant to conventional analgesics, intravenous bisphosphonates can be proposed. In non-responder patients, several case reports suggest the efficacy of a monoclonal antibody directed against the IL-6 receptor which requires to be confirmed by randomized studies.

  18. Acetabular Fractures in the Elderly: Treatment Recommendations

    PubMed Central

    Pagenkopf, Eric; Grose, Andrew; Partal, George

    2006-01-01

    Acetabular fractures in the elderly population are marked by a high degree of variability in terms of patient and fracture characteristics. Successful outcomes depend on application of highly individualized management principles by experienced teams. Reviewed are indications and outcomes associated with various management options, including closed treatment, open reduction internal fixation, and acute or staged total hip arthroplasty. Proper initial management choices are critical, as early failures and subsequent salvage surgery can be accompanied by significant morbidity. Clinical results after ORIF closely follow the quality of articular reduction and the ability to maintain a congruent reduction of the hip joint. Fracture characteristics predictive of anatomic articular reduction should be treated with ORIF. Fracture characteristics predictive of early post-traumatic arthritis should be treated with simultaneous ORIF and THA. Presented is one referral institution’s treatment algorithm and management approach. PMID:18751831

  19. Aerodynamic Investigation of a Cup Anemometer

    NASA Technical Reports Server (NTRS)

    Hubbard, John D; Brescoll, George P

    1934-01-01

    This thesis presents the results of an investigation wherein the change of the normal force coefficient with Reynolds Number was obtained statically for a 15.5-centimeter hemisphere cup under the following conditions: (1) single cup with no interference; (2) single cup with three-cup interference; (3) four cups. The coefficients found in this research vary with Reynolds Number and are high as compared with those of Eiffel. The effect of interference upon a single cup is to increase the drag and normal force coefficients. The curve resulting from the summation of the coefficients for four cups agrees with the static torque curve of a Robinson type cup anemometer. All tests were carried on in the University of Detroit atmospheric wind tunnel during May 1933.

  20. Wear of highly crosslinked polyethylene acetabular components

    PubMed Central

    Callary, Stuart A; Solomon, Lucian B; Holubowycz, Oksana T; Campbell, David G; Munn, Zachary; Howie, Donald W

    2015-01-01

    Background and purpose Wear rates of highly crosslinked polyethylene (XLPE) acetabular components have varied considerably between different published studies. This variation is in part due to the different techniques used to measure wear and to the errors inherent in measuring the relatively low amounts of wear in XLPE bearings. We undertook a scoping review of studies that have examined the in vivo wear of XLPE acetabular components using the most sensitive method available, radiostereometric analysis (RSA). Methods A systematic search of the PubMed, Scopus, and Cochrane databases was performed to identify published studies in which RSA was used to measure wear of XLPE components in primary total hip arthroplasty (THA). Results 18 publications examined 12 primary THA cohorts, comprising only 260 THAs at 2–10 years of follow-up. The mean or median proximal wear rate reported ranged from 0.00 to 0.06 mm/year. However, differences in the manner in which wear was determined made it difficult to compare some studies. Furthermore, differences in RSA methodology between studies, such as the use of supine or standing radiographs and the use of beaded or unbeaded reference segments, may limit future meta-analyses examining the effect of patient and implant variables on wear rates. Interpretation This scoping review confirmed the low wear rates of XLPE in THA, as measured by RSA. We make recommendations to enhance the standardization of reporting of RSA wear results, which will facilitate early identification of poorly performing implants and enable a better understanding of the effects of surgical and patient factors on wear. PMID:25301435

  1. Imaging of craniofacial fibrous dysplasia.

    PubMed

    Lisle, D A; Monsour, P A J; Maskiell, C D

    2008-08-01

    Fibrous dysplasia is a relatively common disorder of bone. It may affect the bones of the face and skull and, in so doing, produce a wide variety of clinical presentations. Plain film assessment of craniofacial fibrous dysplasia may be difficult because of varying appearances and complex, overlapping structures. The MRI appearances of fibrous dysplasia are often non-specific and may be confusing. Findings on CT are also variable, but more commonly lead to a specific diagnosis. This is because of the characteristic ground-glass appearance of woven bone, seen on CT in most if not all cases of craniofacial fibrous dysplasia.

  2. Algorithm for automatic angles measurement and screening for Developmental Dysplasia of the Hip (DDH).

    PubMed

    Al-Bashir, Areen K; Al-Abed, Mohammad; Abu Sharkh, Fayez M; Kordeya, Mohamed N; Rousan, Fadi M

    2015-01-01

    Developmental Dysplasia of the Hip (DDH) is a medical term represent the hip joint instability that appear mainly in infants. The examination for this condition can be done by ultrasound for children under 6 months old and by X-ray for children over 6 months old. Physician's assessment is based on certain angles derived from those images, namely the Acetabular Angle, and the Center Edge Angle. In this paper, we are presenting a novel, fully automatic algorithm for measuring the diagnostic angles of DDH from the X-ray images. Our algorithm consists of Automatic segmentation and extraction of anatomical landmarks from X-ray images. Both of Acetabular angle and Center edge angle are automatically calculated. The analysis included X-ray images for 16 children recruited for the purposed of this study. The automatically acquired angles accuracy for Acetabular Angle was around 85%, and an absolute deviation of 3.4°±3.3° compared to the physician's manually calculated angle. The results of this method are very promising for the future development of an automatic method for screening X-ray images DDH that complement and aid the physicians' manual methods.

  3. Familial ectodermal dysplasia: a peers’ agony

    PubMed Central

    Hegde, Karthik; Kashyap, Roopashri Rajesh; Nair, Gopakumar; Nair, Preeti P

    2013-01-01

    Ectodermal dysplasias include a various group of inherited disorders which share primary defect in the development of two or more tissues of embryonic ectodermal origin. Though there are many subtypes, ectodermal dysplasias are mainly hidrotic ectodermal dysplasia and hypohidrotic ectodermal dysplasia, among which the most common variety is X linked hypohidrotic ectodermal dysplasia. We report a rare case of X linked hypohidrotic ectodermal dysplasia occurring in a family with various skin, hair and oral abnormalities. PMID:23880572

  4. A novel electromagnetic navigation tool for acetabular surgery.

    PubMed

    Lehmann, Wolfgang; Rueger, Johannes M; Nuechtern, Jakob; Grossterlinden, Lars; Kammal, Michael; Hoffmann, Michael

    2015-10-01

    Acetabular fracture surgery is demanding and screw placement along narrow bony corridors remains challenging. It necessitates x-ray radiation for fluoroscopically assisted screw insertion. The purpose of this cadaver study was to evaluate the feasibility, accuracy and operation time of a novel electromagnetic navigation system for screw insertion along predefined acetabular corridors. A controlled laboratory study with a total of 24 electromagnetically navigated screw insertions was performed on 8 cadaveric acetabula. 3 peri-acetabular bony corridors (QSS, Quadrilateral Surface Screw; IAS, Infra-Acetabular Screw; PCS, Posterior Column Screw) were defined and screws were placed in a defined order without fluoroscopy. Operation time was documented. Postoperative CT scans were performed to analyse accuracy of screw placement. Mean cadaver age was 70.4 ± 11.7. Successful screw placement was accomplished in 22 out of 24 (91.7%) cases. The overall mean time for all 3 acetabular screws was 576.6 ± 75.9s. All 3 complications occurred during the placement of the IAS due to an impassable narrow bony corridor. QSS mean length was 50 ± 5mm, IAS mean length was 85 ± 10mm and PCS mean length was 120 ± 5mm. In this cadaver study the novel electromagnetic navigation system was feasible to allow accurate screw placement without fluoroscopy in defined narrow peri-acetabular bony corridors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Effects of the standing program with hip abduction on hip acetabular development in children with spastic diplegia cerebral palsy.

    PubMed

    Macias-Merlo, Lourdes; Bagur-Calafat, Caridad; Girabent-Farrés, Montserrat; A Stuberg, Wayne

    2016-01-01

    Early identification and intervention with conservative measures is important to help manage hip dysplasia in children with a high adductor and iliopsoas tone and delay in weight bearing. The effect of a daily standing program with hip abduction on hip acetabular development in ambulatory children with cerebral palsy was studied. The participants were 26 children with spastic diplegia cerebral palsy (CP), classified at Level III according to the Gross Motor Function Classification System (GMFCS). Thirteen children stood with hip abduction at least 1 h daily from 12 to 14 months of age to 5 years with an individually fabricated standing frame with hip abduction. At the age of 5 years, radiologic results of the study group were compared with a comparison group of 13 children with spastic diplegia CP who had not taken part in a standing program. The migration percentage in all children who stood with abduction remained within stable limits (13-23%) at 5 years of age, in comparison to children who did not stand in abduction (12-47%) (p < 0.01). The results indicate that a daily standing program with hip abduction in the first 5 years may enhance acetabular development in ambulatory children with spastic diplegia CP. Abnormal acetabular development is a problem related to mobility problems and spasticity muscles around the hip. The literature suggests that postural management and standing programs could reduce levels of hip subluxation and increase function in children with cerebral palsy. A standing program with hip abduction can be a beneficial to develop more stable hips in children with spastic diplegic GMFCS level III.

  6. Cementation of an acetabular liner into a well-fixed acetabular shell during revision total hip arthroplasty.

    PubMed

    Springer, Bryan D; Hanssen, Arlen D; Lewallen, David G

    2003-10-01

    Cementing a polyethylene liner into a well-fixed acetabular shell during revision hip arthroplasty may be appropriate in select patients. The purpose of this study was to review our early results with this technique. Sixteen patients with >2-year follow-up or who had any complications at <2 years from surgery were identified. Indications for this technique included: failure of the previous locking mechanism, significant polyethylene wear, malposition of the well-fixed metal shell, and previous removal of the liner with a retained acetabular shell. One acetabular shell has been revised at 13 months for multiple dislocations. Hip scores improved an average of 24.2 points. Radiographs revealed no polyethylene dissociation or acetabular loosening. Complications occurred in 7 patients. Initial results appear successful at providing secure fixation, while preventing the bone loss that might occur with removal of a well-fixed component.

  7. Three Year RSA Evaluation of Vitamin E Diffused Highly Cross-linked Polyethylene Liners and Cup Stability.

    PubMed

    Sillesen, Nanna H; Greene, Meridith E; Nebergall, Audrey K; Nielsen, Poul T; Laursen, Mogens B; Troelsen, Anders; Malchau, Henrik

    2015-07-01

    Vitamin E diffusion into highly cross-linked polyethylene (E-XLPE) is a method for enhancing oxidative stability of acetabular liners. The purpose of this study was to evaluate in vivo penetration of E-XLPE using radiostereometric analysis (RSA). Eighty-four hips were recruited into a prospective 10-year RSA. This is the first evaluation of the multicenter cohort after 3-years. All patients received E-XLPE liners (E1, Biomet) and porous-titanium coated cups (Regenerex, Biomet). There was no difference (P=0.450) in median femoral head penetration into the E-XLPE liners at 3-years comparing cobalt-chrome heads (-0.028mm; inter-quartile range (IQR) - 0.065 to 0.047) with ceramic heads (-0.043mm, IQR - 0.143to0.042). The 3-year follow-up indicates minimal E-XLPE liner penetration regardless of head material and minimal early cup movement.

  8. Validation and usefulness of a computer-assisted cup-positioning system in total hip arthroplasty. A prospective, randomized, controlled study.

    PubMed

    Parratte, Sebastien; Argenson, Jean-Noel A

    2007-03-01

    Malpositioning of the acetabular component during total hip arthroplasty increases the risk of dislocation, reduces the range of motion, and can be responsible for early wear and loosening. The purpose of this study was to compare computer-assisted with freehand insertion of the acetabular component. A randomized, controlled, matched prospective study of two groups of thirty patients each was performed. In the first group, cup positioning was assisted by an imageless computer-assisted surgical system based on bone morphing. In the control group, the cup was placed freehand. All of the patients were operated on by the same surgeon through an anterolateral approach. Cup anteversion and abduction angles were measured on three-dimensional computed tomography reconstructions postoperatively for each patient by an independent observer using special cup-evaluation software. There were sixteen men and fourteen women in each group, and the mean body-mass index was approximately 25 in each group. The computer-assisted procedure took a mean of twelve minutes longer than the freehand procedure. Fifty-seven percent (seventeen) of the thirty cups placed freehand and 20% (six) of the thirty in the computer-assisted group were outside of the defined safe zone (outliers). This difference was significant (p = 0.002). There were no differences between the computer-assisted group and the freehand-placement group with regard to the mean abduction and anteversion angles, but there was a significant heterogeneity of variances, with the lowest variations in the computer-assisted group. Use of an imageless navigation system can improve cup positioning in total hip arthroplasty by reducing the percentage of outliers.

  9. Dummy Cup Helps Robot-Welder Programmers

    NASA Technical Reports Server (NTRS)

    Gordon, Stephen S.

    1990-01-01

    Dummy gas cup used on torch of robotic welder during programming and practice runs. Made of metal or plastic, dummy cup inexpensive and durable. Withstands bumps caused by programming errors, and is sized for special welding jobs within limited clearances. After robot satisfactorily programmed, replaced by ceramic cup of same dimensions for actual welding.

  10. Dummy Cup Helps Robot-Welder Programmers

    NASA Technical Reports Server (NTRS)

    Gordon, Stephen S.

    1990-01-01

    Dummy gas cup used on torch of robotic welder during programming and practice runs. Made of metal or plastic, dummy cup inexpensive and durable. Withstands bumps caused by programming errors, and is sized for special welding jobs within limited clearances. After robot satisfactorily programmed, replaced by ceramic cup of same dimensions for actual welding.

  11. Theoretical Implications of Periacetabular Osteotomy in Various Dysplastic Acetabular Cartilage Defects as Determined by Finite Element Analysis

    PubMed Central

    Xu, Meng; Qu, Wenrui; Wang, Yanbing; Zhong, Lei; Zhu, Zhe; Li, Wei; Zhao, Xin; Wang, Jincheng; Sun, Yu

    2016-01-01

    Background Different extents and locations of acetabular cartilage defect have been supposed to be a major cause of undesirable outcomes of periacetabular osteotomy (PAO) in patients with developmental dysplasia of the hip (DDH). This study aimed to verify whether different locations of cartilage deficiency affect the biomechanical environment in a three-dimensional model utilizing finite element analysis (FEA). Material/Methods We developed 3 DDH models – DDH-1 (normal shape), DDH-2 (superior defect), and DDH-3 (anterosuperior defect) – by deforming from a normal hip model. We also developed 3 PAO models – PAO-1, PAO-2, and PAO-3 – through rotating osteotomized fragments. Results The maximum von Mises stress in the normal hip was 13.06 MPa. In the DDH-1 model, the maximum value on the load-bearing area decreased from 15.49 MPa pre-PAO to 14.28 MPa post-PAO, while stresses in the DDH-2 and DDH-3 models were higher than in the DDH-1 model, both pre-PAO and post-PAO (30.46 MPa to 26.04 MPa for DDH-2; 33.89 MPa to 27.48 MPa for DDH-3). Conclusions This study shows that, both pre- and post-PAO, different types of cartilage deficiency affect the biomechanical environment. Furthermore, in dysplastic hips, obtaining accurate three-dimensional information about the acetabular cartilage can contribute substantially to PAO decision making. PMID:28017958

  12. Theoretical Implications of Periacetabular Osteotomy in Various Dysplastic Acetabular Cartilage Defects as Determined by Finite Element Analysis.

    PubMed

    Xu, Meng; Qu, Wenrui; Wang, Yanbing; Zhong, Lei; Zhu, Zhe; Li, Wei; Zhao, Xin; Wang, Jincheng; Sun, Yu

    2016-12-26

    BACKGROUND Different extents and locations of acetabular cartilage defect have been supposed to be a major cause of undesirable outcomes of periacetabular osteotomy (PAO) in patients with developmental dysplasia of the hip (DDH). This study aimed to verify whether different locations of cartilage deficiency affect the biomechanical environment in a three-dimensional model utilizing finite element analysis (FEA). MATERIAL AND METHODS We developed 3 DDH models - DDH-1 (normal shape), DDH-2 (superior defect), and DDH-3 (anterosuperior defect) - by deforming from a normal hip model. We also developed 3 PAO models - PAO-1, PAO-2, and PAO-3 - through rotating osteotomized fragments. RESULTS The maximum von Mises stress in the normal hip was 13.06 MPa. In the DDH-1 model, the maximum value on the load-bearing area decreased from 15.49 MPa pre-PAO to 14.28 MPa post-PAO, while stresses in the DDH-2 and DDH-3 models were higher than in the DDH-1 model, both pre-PAO and post-PAO (30.46 MPa to 26.04 MPa for DDH-2; 33.89 MPa to 27.48 MPa for DDH-3). CONCLUSIONS This study shows that, both pre- and post-PAO, different types of cartilage deficiency affect the biomechanical environment. Furthermore, in dysplastic hips, obtaining accurate three-dimensional information about the acetabular cartilage can contribute substantially to PAO decision making.

  13. Coffee Cup Atomic Force Microscopy

    ERIC Educational Resources Information Center

    Ashkenaz, David E.; Hall, W. Paige; Haynes, Christy L.; Hicks, Erin M.; McFarland, Adam D.; Sherry, Leif J.; Stuart, Douglas A.; Wheeler, Korin E.; Yonzon, Chanda R.; Zhao, Jing; Godwin, Hilary A.; Van Duyne, Richard P.

    2010-01-01

    In this activity, students use a model created from a coffee cup or cardstock cutout to explore the working principle of an atomic force microscope (AFM). Students manipulate a model of an AFM, using it to examine various objects to retrieve topographic data and then graph and interpret results. The students observe that movement of the AFM…

  14. Coffee Cup Atomic Force Microscopy

    ERIC Educational Resources Information Center

    Ashkenaz, David E.; Hall, W. Paige; Haynes, Christy L.; Hicks, Erin M.; McFarland, Adam D.; Sherry, Leif J.; Stuart, Douglas A.; Wheeler, Korin E.; Yonzon, Chanda R.; Zhao, Jing; Godwin, Hilary A.; Van Duyne, Richard P.

    2010-01-01

    In this activity, students use a model created from a coffee cup or cardstock cutout to explore the working principle of an atomic force microscope (AFM). Students manipulate a model of an AFM, using it to examine various objects to retrieve topographic data and then graph and interpret results. The students observe that movement of the AFM…

  15. Desbuquois dysplasia, a reevaluation with abnormal and "normal" hands: radiographic manifestations.

    PubMed

    Faivre, Laurence; Cormier-Daire, Valérie; Eliott, Alison M; Field, Fiona; Munnich, Arnold; Maroteaux, Pierre; Le Merrer, Martine; Lachman, Ralph

    2004-01-01

    Radiological features of 35 patients with the diagnosis of Desbuquois dysplasia were analyzed. The diagnosis of Desbuquois dysplasia was based on the association of specific facial alterations, markedly short stature of prenatal onset, joint laxity, "Swedish key" appearance of the proximal femur, and advanced carpal and tarsal bone age. Patients were divided into two groups, depending on whether or not typical hands with an extra ossification center distal to the second metacarpal and/or a delta phalanx of the thumb were present (group 1, 46%) or absent (group 2, 54%). In this study, beside the "Swedish key" appearance of the proximal femur and advanced carpal and tarsal ossification, we were able to define three additional major radiographic criteria for the diagnosis of Desbuquois dysplasia, including flat acetabular roof, elevated greater trochanter, and proximal fibular overgrowth. Other manifestations included wide metaphyses, flat epiphyses, coxa valga, coronal and sagittal clefts of the vertebrae, wide anterior rib portions, medial deviation of the foot, and enlarged first metatarsal. We conclude that characteristic hand abnormalities are not mandatory for the diagnosis of Desbuquois dysplasia. Copyright 2003 Wiley-Liss, Inc.

  16. Are cam and pincer deformities as common as dysplasia in Japanese patients with hip pain?

    PubMed

    Mori, R; Yasunaga, Y; Yamasaki, T; Nakashiro, J; Fujii, J; Terayama, H; Ohshima, S; Ochi, M

    2014-02-01

    In Japan, osteoarthritis (OA) of the hip secondary to acetabular dysplasia is very common, and there are few data concerning the pathogeneses and incidence of femoroacetabular impingement (FAI). We have attempted to clarify the radiological prevalence of painful FAI in a cohort of Japanese patients and to investigate the radiological findings. We identified 176 symptomatic patients (202 hips) with Tönnis grade 0 or 1 osteoarthritis, whom we prospectively studied between August 2011 and July 2012. There were 61 men (65 hips) and 115 women (137 hips) with a mean age of 51.8 years (11 to 83). Radiological analyses included the α-angle, centre-edge angle, cross-over sign, pistol grip deformity and femoral head neck ratio. Of the 202 hips, 79 (39.1%) had acetabular dysplasia, while 80 hips (39.6%) had no known aetiology. We found evidence of FAI in 60 hips (29.7%). Radiological FAI findings associated with cam deformity were the most common. There was a significant relationship between the pistol grip deformity and both the α-angle (p < 0.001) and femoral head-neck ratio (p = 0.024). Radiological evidence of symptomatic FAI was not uncommon in these Japanese patients.

  17. Traumatic Periprosthetic Acetabular Fracture Treated with One-Stage Exchange and Bone Reconstruction Using a Synthetic Bone Graft Substitute.

    PubMed

    Svacina, Jan

    2016-01-01

    A case of a traumatic periprosthetic acetabular fracture in an elderly patient, which was treated by one-stage hip exchange with implantation of an antiprotrusio cage and reconstruction of the acetabular bone loss with an injectable calcium sulphate/hydroxyapatite bone graft substitute, is reported. The paste-like bone graft substitute was injected through the holes of the antiprotrusio cage. After a setting time of 15 minutes, a low-profile cup was cemented onto the cage using polymethylmethacrylate and a new stem was inserted. The patient was encouraged to ambulate three days postoperatively weight-bearing as tolerated. At the one-year follow-up visit the patient was ambulatory and full weight-bearing without any walking aids. The follow-up radiographs demonstrated stable position and articulation of the revision hip arthroplasty with no signs of loosening of the antiprotrusio cage. However, the most interesting finding was that the bone graft substitute had remodelled to a great extent into bone. This calcium sulphate/hydroxyapatite composite shows high osteoconductive potential and can be used to regenerate bone stock in revision arthroplasty.

  18. Traumatic Periprosthetic Acetabular Fracture Treated with One-Stage Exchange and Bone Reconstruction Using a Synthetic Bone Graft Substitute

    PubMed Central

    2016-01-01

    A case of a traumatic periprosthetic acetabular fracture in an elderly patient, which was treated by one-stage hip exchange with implantation of an antiprotrusio cage and reconstruction of the acetabular bone loss with an injectable calcium sulphate/hydroxyapatite bone graft substitute, is reported. The paste-like bone graft substitute was injected through the holes of the antiprotrusio cage. After a setting time of 15 minutes, a low-profile cup was cemented onto the cage using polymethylmethacrylate and a new stem was inserted. The patient was encouraged to ambulate three days postoperatively weight-bearing as tolerated. At the one-year follow-up visit the patient was ambulatory and full weight-bearing without any walking aids. The follow-up radiographs demonstrated stable position and articulation of the revision hip arthroplasty with no signs of loosening of the antiprotrusio cage. However, the most interesting finding was that the bone graft substitute had remodelled to a great extent into bone. This calcium sulphate/hydroxyapatite composite shows high osteoconductive potential and can be used to regenerate bone stock in revision arthroplasty. PMID:27446621

  19. Use of porous tantalum components in Paprosky two and three acetabular revision. A minimum five-year follow-up of fifty one hips.

    PubMed

    Flecher, Xavier; Appy, Benjamin; Parratte, Sébastien; Ollivier, Matthieu; Argenson, Jean-Noel

    2017-05-01

    Recent studies have reported short-term favourable results of tantalum-made components in acetabular revisions with bone loss. However, there is a lack of information regarding the mid to long-term results of such components. The objective of this study was to analyse the outcome and survivorship of acetabular revision hip arthroplasty using tantalum components for loosening associated with bone loss at a minimum of five-year follow-up. We retrospectively reviewed 51 consecutive patients (51 hips) who had an acetabular revision using porous tantalum components at a minimum follow-up of five years. The mean age was 64 years (range, 31-87). There were 27 males and 24 females, 47 right hips and four left hips. Twenty-five (49 %) included a femoral revision. According to Paprosky's classification 18 hips were classified type 2A, 11 type 2B, ten type 2C, seven type 3A and five type 3B. No bone grafting was performed. Sixteen hips (31.3 %) required the use of additional tantalum-made augments stabilized by screws and cement at the cup-augment interface. At a mean followup of 6.8 years (range, 5.1-10 years), the Harris hip score improved from 44 pre- operatively (range, 23-72) to 84 post-operatively (range, 33-98). The mean post-operative hip centre position in relation to the teardrop was 29 mm (range, 20-43 mm) horizontally and 21 mm (range, 8-36 mm) vertically. The mean acetabular inclination was 42° (range, 17-60°). Six hips (11.7 %) required a re-operation without component revision (two for chronic instability, one ossification removal, one haematoma, one deep infection and one periprosthetic femoral fracture). One patient required a cup re-revision for septic loosening. No aseptic loosening occurred. At last followup the radiological analysis showed one evolutive osteolysis and one screw breakage. The global survivorship was 92.3 % at 64 months. If only aseptic loosening was defined as the end-point the survivorship was 100 % at 64 months. When

  20. Fate of the unrevised cemented stem following cup only revision: 227 hips at an average of 6 years follow-up.

    PubMed

    McGonagle, L; Siney, P D; Raut, V V

    2015-11-01

    After primary total hip replacement, aseptic loosening of the acetabular cup is more common than loosening of the femoral stem. Removal of a well-fixed stem adds to operative time, blood loss, risk of bone loss and fracture. There is limited evidence that isolated cup revision can be a safe option in revision hip arthroplasty. We question the following regarding the unrevised cemented stem after isolated cup revision: 1) Does the unrevised stem require revision after isolated cup revision? 2) When is the stem subsequently revised? 3) Why is the stem subsequently revised? 4) Do unrevised stems exhibit radiographic loosening? We hypothesise that after isolated cup revision most unrevised stems do not need subsequent revision, and that most do not exhibit evidence of radiographic loosening. A retrospective analysis of all patients who underwent revision of the acetabular component only during revision hip arthroplasty between March 1970 and July 2013 was carried out. We assessed survival of the unrevised stem, reasons for subsequent revision, plus radiographic analysis for stem loosening. Two hundred and twenty-seven hips were included [215 patients with an average age at the time of primary surgery was 47 (13-70) years]. The Charnley stem was used in 161 cases; C-stem 65, Howse 1. Average time between primary surgery and cup revision was 15.9 (1.6-33.4) years. Average follow-up for all stems post-isolated cup revision was 6.1 (0.1-30.7) years. Twenty-eight stems (12.3%) were subsequently revised 5.1 (0.1-12.6) years after the isolated cup revision. Reasons for subsequent revision were: aseptic loosening (10); infection (8); dislocation (6); unreconstructable joint post-loose cup removal (2); fracture (2). Radiographic review was possible on 140 cases. Five femoral stems were revised and 2 others showed evidence of possible radiological loosening but were not revised. To our knowledge this is the largest series showing that isolated cup revision in the place of a well

  1. Accuracy of Cup Positioning With the Computed Tomography-Based Two-dimensional to Three-Dimensional Matched Navigation System: A Prospective, Randomized Controlled Study.

    PubMed

    Yamada, Kazuki; Endo, Hirosuke; Tetsunaga, Tomonori; Miyake, Takamasa; Sanki, Tomoaki; Ozaki, Toshifumi

    2017-08-12

    The accuracy of various navigation systems used for total hip arthroplasty has been described, but no publications reported the accuracy of cup orientation in computed tomography (CT)-based 2D-3D (two-dimensional to three-dimensional) matched navigation. In a prospective, randomized controlled study, 80 hips including 44 with developmental dysplasia of the hips were divided into a CT-based 2D-3D matched navigation group (2D-3D group) and a paired-point matched navigation group (PPM group). The accuracy of cup orientation (absolute difference between the intraoperative record and the postoperative measurement) was compared between groups. Additionally, multiple logistic regression analysis was performed to evaluate patient factors affecting the accuracy of cup orientation in each navigation. The accuracy of cup inclination was 2.5° ± 2.2° in the 2D-3D group and 4.6° ± 3.3° in the PPM group (P = .0016). The accuracy of cup anteversion was 2.3° ± 1.7° in the 2D-3D group and 4.4° ± 3.3° in the PPM group (P = .0009). In the PPM group, the presence of roof osteophytes decreased the accuracy of cup inclination (odds ratio 8.27, P = .0140) and the absolute value of pelvic tilt had a negative influence on the accuracy of cup anteversion (odds ratio 1.27, P = .0222). In the 2D-3D group, patient factors had no effect on the accuracy of cup orientation. The accuracy of cup positioning in CT-based 2D-3D matched navigation was better than in paired-point matched navigation, and was not affected by patient factors. It is a useful system for even severely deformed pelvises such as developmental dysplasia of the hips. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Preliminary Biomechanical Study of Different Acetabular Reinforcement Devices for Acetabular Reconstruction

    PubMed Central

    Tai, Ching-Lung; Lee, Po-Yi; Hsieh, Pang-Hsing

    2015-01-01

    Background Acetabular reinforcement devices (ARDs) are frequently used as load-sharing devices to allow allograft incorporation in revision hip arthroplasty with massive acetabular bone loss. The key to a successful reconstruction is robust fixation of the device to the host acetabulum. Interlocking fixation is expected to improve the initial stability of the postoperative construct. However, all commercially available ARDs are designed with non-locking fixation. This study investigates the efficacy of standard ARDs modified with locking screw mechanisms for improving stability in acetabular reconstruction. Methods Three types of ARDs were examined to evaluate the postoperative compression and angular stability: i) standard commercial ARDs, ii) standard ARDs modified with monoaxial and iii) standard ARDs modified with polyaxial locking screw mechanisms. All ARDs were implanted into osteomized synthetic pelvis with pelvic discontinuity. Axial compression and torsion tests were then performed using a servohydraulic material testing machine that measured load (angle) versus displacement (torque). Initial stability was compared among the groups. Results Equipping ARDs with interlocking mechanisms effectively improved the initial stability at the device/bone interface compared to standard non-locked ARDs. In both compression and torsion experiments, the monoaxial interlocking construct demonstrated the highest construct stiffness (672.6 ± 84.1 N/mm in compression and 13.3 ± 1.0 N·m/degree in torsion), whereas the non-locked construct had the lowest construct stiffness (381.4 ± 117.2 N/mm in compression and 6.9 ± 2.1 N·m/degree in torsion) (P < 0.05). Conclusions Our study demonstrates the potential benefit of adding a locking mechanism to an ARD. Polyaxial ARDs provide the surgeon with more flexibility in placing the screws at the cost of reduced mechanical performance. This in vitro study provides a preliminary evaluation of biomechanical performance for ARDs

  3. Comparative study of comminuted posterior acetabular wall fracture treated with the Acetabular Tridimensional Memory Fixation System.

    PubMed

    Zhang, Yuntong; Zhao, Xue; Tang, Yang; Zhang, Chuncai; Xu, Shuogui; Xie, Yang

    2014-04-01

    Posterior wall fractures are one of the most common acetabular fractures. However, only 30% of these fractures involve a single large fragment, and comminuted acetabular posterior wall fractures pose a particular surgical challenge. The purpose of this study was to compare outcomes between patients who received fixation for comminuted posterior wall fracture using the Acetabular Tridimensional Memory Fixation System (ATMFS) and patients who underwent fixation with conventional screws and buttress plates (Plates group). Between April 2003 and May 2007, 196 consecutive patients who sustained a comminuted posterior wall fracture of acetabulum were treated with ATMFS or conventional screws and buttress plates. Operative time, fluoroscopy time, blood loss, and any intra-operative complications were recorded. Plain AP and lateral radiographs were obtained at all visits (Matta's criteria). Modified Merle d' Aubigne-Postel score, and Mos SF-36 score were compared between groups. Fifty patients were included in the analysis with 26 in the ATMFS group and 24 in the Plates group. The mean follow-up time was 57.5 months, ranging from 31 to 69 months. All patients had fully healed fractures at the final follow-up. There was no difference in clinical outcomes or radiological evaluations between groups. Patients with comminuted posterior wall fractures of the acetabulum treated with the ATMFS or conventional screws and buttress plate techniques achieve a good surgical result. Both techniques are safe, reliable, and practical. Use of the ATMFS technique may reduce blood loss and improve rigid support to marginal bone impaction. The use ATMFS may need additional support when fractures involve the superior roof. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Cupping for Treating Pain: A Systematic Review

    PubMed Central

    Kim, Jong-In; Lee, Myeong Soo; Lee, Dong-Hyo; Boddy, Kate; Ernst, Edzard

    2011-01-01

    The objective of this study was to assess the evidence for or against the effectiveness of cupping as a treatment option for pain. Fourteen databases were searched. Randomized clinical trials (RCTs) testing cupping in patients with pain of any origin were considered. Trials using cupping with or without drawing blood were included, while trials comparing cupping with other treatments of unproven efficacy were excluded. Trials with cupping as concomitant treatment together with other treatments of unproven efficacy were excluded. Trials were also excluded if pain was not a central symptom of the condition. The selection of studies, data extraction and validation were performed independently by three reviewers. Seven RCTs met all the inclusion criteria. Two RCTs suggested significant pain reduction for cupping in low back pain compared with usual care (P < .01) and analgesia (P < .001). Another two RCTs also showed positive effects of cupping in cancer pain (P < .05) and trigeminal neuralgia (P < .01) compared with anticancer drugs and analgesics, respectively. Two RCTs reported favorable effects of cupping on pain in brachialgia compared with usual care (P = .03) or heat pad (P < .001). The other RCT failed to show superior effects of cupping on pain in herpes zoster compared with anti-viral medication (P = .065). Currently there are few RCTs testing the effectiveness of cupping in the management of pain. Most of the existing trials are of poor quality. Therefore, more rigorous studies are required before the effectiveness of cupping for the treatment of pain can be determined. PMID:19423657

  5. Periacetabular Osteotomy Redirects the Acetabulum and Improves Pain in Charcot-Marie-Tooth Hip Dysplasia With Higher Complications Compared With Developmental Dysplasia of the Hip.

    PubMed

    Novais, Eduardo N; Kim, Young-Jo; Carry, Patrick M; Millis, Michael B

    2016-12-01

    The Bernese periacetabular osteotomy (PAO) is a well-accepted reorientation pelvic osteotomy used to treat symptomatic acetabular dysplasia secondary to developmental dysplasia of the hip (DDH). However, there are limited data regarding PAO in patients with symptomatic hip dysplasia secondary to Charcot-Marie-Tooth disease. We compared patients who underwent PAO for the treatment of Charcot-Marie-Tooth disease hip dysplasia (CMTHD group) with patients who underwent PAO for treatment of hip dysplasia secondary to DDH in terms of (1) modified Harris Hip scores; (2) radiographic correction of acetabular dysplasia; and (3) the rate of complications. Twenty-seven subjects with Charcot-Marie-Tooth disease who underwent a PAO between January 1991 and December 2010 were matched to 54 subjects with DDH on the basis of sex, age, date of surgery, and body mass index. Preoperative and postoperative hip functional scores and radiographic data were collected with a minimum 2-year follow-up. The modified Harris Hip Scores (mHHS) assessed functional hip outcomes. Radiographic variables included lateral (LCEA) and anterior (ACEA) center-edge angles, Tönnis angle and Tönnis grade of arthritis. Postoperative complications were classified according to a modified Dindo-Clavien system. At latest follow-up mHHS improved in the CMTHD group (preoperative median 63; (interquartile range [IQR]=54-70 to postoperative median 88; IQR=74-91); P=0.004) and in the DDH groups (preoperative median 71; IQR=58-83 to postoperative median 86; IQR=73-96; P=0.002) with no difference between the 2 groups (P=0.631). Radiographic improvement (LCEA: mean difference, 36 degrees, 95% confidence interval [CI], 30-41 degrees, P<0.001; ACEA: mean difference, 27 degrees, 95% CI, 20-33 degrees, P<0.001; Tönnis angles: mean difference, 21 degrees, 95% CI, 15-26 degrees, P<0.001) was achieved in the CMTHD group. Similarly, radiographic improvements in LCEA (mean difference, 33 degrees, 95% CI, 29-37 degrees, P<0

  6. Three dimensional-CT evaluation of femoral neck anteversion, acetabular anteversion and combined anteversion in unilateral DDH in an early walking age group.

    PubMed

    Jia, JingYu; Li, LianYong; Zhang, LiJun; Zhao, Qun; Liu, XiJuan

    2012-01-01

    At present, the indications for femoral derotational osteotomy remain controversial due to the inconsistent findings in femoral neck anteversion in developmental dysplasia of the hip (DDH). Moreover, combined anteversion is not assessed in unilateral DDH using three dimensional-CT. Therefore, the purposes of our study were to observe whether the femoral neck anteversion (FA), acetabular anteversion (AA) and combined anteversion (CA) on the dislocated hips were universally presented in unilateral DDH according to the classification system of Tönnis. Sixty-two patients with unilateral dislocation of hip were involved in the study, including 54 females and eight males with a mean age of 21.63 months (range, 18-48 months). The FA, AA and CA were measured and compared between the dislocated hips and the unaffected hips. Although no significant difference was observed in FA between the dislocated hips and the unaffected hips (P = 0.067, 0.132, respectively) in Tönnis II and III type, FA was obviously increased on the dislocated hips compared with the unaffected hips in Tönnis IV type. Increased AA on the dislocated hips was a universal finding in Tönnis II, III and IV types. Meanwhile, a wide safe range of CA from 24° to 62° was demonstrated on the unaffected hips. Femoral derotational osteotomy seems not to be necessary in Tönnis II and III types in unilateral DDH. Femoral derotational osteotomy should be considered in DDH, especially in Tönnis IV type, if the CA is still above 62° and the hip joints present instability in operation after abnormal acetabular anteversion, acetabular index and acetabular coverage of the femoral head are recovered to normal range through pelvic osteotomy.

  7. The reliability of the anterior pelvic plane for computer navigated acetabular component placement during total hip arthroplasty: prospective study with the EOS imaging system.

    PubMed

    Barbier, O; Skalli, W; Mainard, L; Mainard, D

    2014-10-01

    Computer navigated total hip arthroplasty is mostly based on the use of the anterior pelvic plane (APP) as a reference. EOS is a new imaging system that provides three-dimensional analysis of the pelvis in a functional position with a low dose of radiation. The aim of this study was to evaluate the reliability of the APP for placement of the cup during computer navigated THA using EOS. The reliability of the APP is limited for the placement of the acetabular cup during computer navigated THA. This was a prospective monocentric study using the EOS imaging system evaluating 44 patients in the standing position three months after computer navigated THA (Orthopilot). Reproducibility of EOS measurements were analyzed using SterEOS software and the reliability of the navigation data for the position of the cup were assessed. Intra and interobserver reproducibility of the measurements of the orientation of the cup by EOS were good with correlation coefficients above 93% and 95% and confidence intervals of less than ±5°. Mean cup inclination and anteversion were 41.3° and 20.9° and 44.3° and 29.5° respectively in operatively and post-operatively. The differences between measurements of operative cup inclination using computer assisted navigation and the post-operative EOS measurements were significant (P<0.05) with a correlation coefficient of less than 40%. Our study confirms the lack of precision of the APP as a reference for positioning of the acetabular component, especially in relation to anteversion. Although for many years the APP was considered to be a global reference, in fact, it is subject to significant inter-individual variations and variations during changes in position. These factors, associated with the difficulty of determining the preoperative APP, explain the lack of reliability of this reference. Preoperative evaluation of the orientation of APP by EOS and its integration into the navigation system could help the operator position these components

  8. Skeletal Dysplasias: An Overview.

    PubMed

    Offiah, Amaka C

    2015-01-01

    Constitutional disorders of bone, commonly termed skeletal dysplasias (SDs), are inherited disorders of cartilage and/or bone that affect their growth, morphometry and integrity. Associated skeletal abnormalities are usually but not invariably symmetrical. They may be classified as osteochondrodysplasias, which are conditions associated with abnormalities of the growth (dysplasias) or texture (osteodystrophy) of bone and/or cartilage, or dysostoses, which are conditions secondary to abnormal blastogenesis (occurring at or around the 6th week of in utero life). Skeletal involvement may also occur in other multisystem hereditary and acquired syndromes. The 2010 Nosology and Classification of Genetic Skeletal Disorders listed 456 conditions, of which approximately 50 are perinatally lethal, and 316 are associated with one or more of 226 genes. When an SD is suspected, a standard series of radiographs, collectively known as a skeletal survey, should be performed. The diagnosis of individual conditions is highly dependent on radiographic pattern recognition, which is achieved through a systematic review of the images and enhanced by discussion with colleagues and through the use of available tools, such as atlases and digital databases. This article summarises a systematic approach to the diagnosis of SDs, demonstrated using examples of some of the more common lethal and non-lethal conditions. © 2015 S. Karger AG, Basel.

  9. [Arrhythmogenic right ventricular dysplasia].

    PubMed

    Maia, I G; Sá, R; Bassan, R; Alves, P; Ribeiros, J C; Loyola, L H; Cruz Filho, F E; Valverde, A; Belém, L

    1991-08-01

    To evaluate the clinical findings and complementary investigation to support the diagnosis of arrhythmogenic right ventricular dysplasia. Six males with a mean age of 40 years old with episodes of sustained ventricular tachycardia with left bundle branch block pattern. All patients were submitted to a clinical investigation, EKG X rays and echocardiograms. In five patients an electrophysiologic study was performed. All patients were treated with anti-arrhythmic drugs. Palpitation was the most common complaint. T-wave inversion in leads V1-V3 was present in 4 patients. An epsilon wave was noted in 2 patients. The chest X ray was abnormal in only 1 patient. All patients had an abnormal echocardiogram, with consisted in the dilatation of the outflow tract of the RV and hypocontractility. In 2 patients aneurysm of the basal RV free wall below tricuspid valve were detected. Ventricular post-excitation waves were present in 4 patients. After a mean follow-up of 37 months, 5 patients were asymptomatic with anti-arrhythmic drugs and one in therapeutic adjustment. In patients with ventricular tachycardia with left bundle branch block pattern, the diagnosis of arrhythmogenic right ventricular dysplasia was substantiated by echocardiographic data and electrocardiographic findings such a T-wave inversion during sinus rhythm and ventricular post-excitation waves. The results obtained with anti-arrhythmic drugs in our study group, suggest that drug therapy should be the first and best approach to treat patients with this type of pathology.

  10. Survival of uncemented cups from a single manufacturer implanted from 1985 to 2013: Finnish Arthroplasty Register data.

    PubMed

    Palomäki, Antton; Lempainen, Lasse; Matilainen, Markus; Eskelinen, Antti; Remes, Ville; Virolainen, Petri; Mäkelä, Keijo T

    2017-03-01

    Total hip arthroplasty (THA) with uncemented implants has been a relatively common procedure in Finland during the recent decades. The most common brand of uncemented implants was chosen for further analysis to study the survivorship of this uncemented cup design in comparison to cemented references. Since 1980, The Finnish Arthroplasty Register has collected information on THAs on a national level. This study was based on information of THAs recorded in the Finnish Arthroplasty Register from 1985 to 2013. If patient had undergone bilateral THA, only the first one was included. Altogether, 49,289 THAs were included. The overall 10-year implant survivorship of uncemented implants was 84.3% (95% CI 83.5-85.0%) and of cemented implants 90.6% (90.2-90.0%). The 10-year survival of the contemporary uncemented implants was 90.8% (94.0-95.5%) and 88.5% (84.2-91.7%). The most recently introduced uncemented cup designs had good survivorship rates at 5 years; 10-year survival data are not yet available. We found that modern uncemented cup designs may provide good long-term survivorship rates comparable with the gold standard of cemented cups. However, polyethylene wear, liner problems and periosthetic osteolysis may still occur, also with modern uncemented acetabular components.

  11. Validation of FE micromotions and strains around a press-fit cup: introducing a new micromotion measuring technique.

    PubMed

    Clarke, S G; Phillips, A T M; Bull, A M J

    2012-07-01

    Finite element (FE) analysis provides an useful tool with which to analyze the potential performance of implantations in a variety of surgical, patient and design scenarios. To enable the use of FE analysis in the investigation of such implants, models must be experimentally validated. Validation of a pelvic model with an implanted press-fit cup in terms of micromotion and strain is presented here. A new method of micromotion has been introduced to better describe the overall movement of the cup within the pelvis. The method uses a digitizing arm to monitor the relative movement between markers on the cup and the surrounding acetabulum. FE analysis was used to replicate an experimental set up using a synthetic hemi-pelvis with a press-fitted all-metal cup, subject to the maximum loading observed during normal walking. The work presented here has confirmed the ability of FE models to accurately describe the mechanical performance of the press-fitted acetabulum and surrounding bone under typical loading conditions in terms of micromotion and strain distribution, but has demonstrated limitations in its ability to predict numerical micromotion values. A promising digitizing technique for measuring acetabular micromotions has also been introduced.

  12. VALIDATION OF FE MICROMOTIONS AND STRAINS AROUND A PRESS-FIT CUP: INTRODUCING A NEW MICROMOTION MEASURING TECHNIQUE

    PubMed Central

    Clarke, S G; Phillips, A T M; Bull, A M J

    2014-01-01

    Finite element analysis provides a useful tool with which to analyse the potential performance of implantations in a variety of surgical, patient and design scenarios. To enable the use of finite element analysis in the investigation of such implants, models must be experimentally validated. Validation of a pelvic model with an implanted press-fit cup in terms of micromotion and strain is presented here. A new method of micromotion has been introduced to better describe the overall movement of the cup within the pelvis. The method uses a digitizing arm to monitor the relative movement between markers on the cup and the surrounding acetabulum. Finite element analysis was used to replicate an experimental set up using a synthetic hemi-pelvis with a press-fitted all-metal cup was subject to the maximum loading observed during normal walking. The work presented here has confirmed the ability of finite element models to accurately describe the mechanical performance of the press-fitted acetabulum and surrounding bone under typical loading conditions in terms of micromotion and strain distribution, but has demonstrated limitations in its ability to predict numerical micromotion values. A promising digitizing technique for measuring acetabular micromotions has also been introduced. PMID:22350664

  13. Patient Symptomatology in Anal Dysplasia.

    PubMed

    Hicks, Caitlin W; Wick, Elizabeth C; Leeds, Ira L; Efron, Jonathan E; Gearhart, Susan L; Safar, Bashar; Fang, Sandy H

    2015-06-01

    High-resolution anoscopy (HRA) is becoming increasingly advocated as a method of screening for anal dysplasia in high-risk patients. To describe, through HRA findings, the association between patient symptomatology and anal dysplasia among patients at high risk for anal dysplasia. Univariable and multivariable analyses were conducted of data from a prospectively maintained HRA database on all patients undergoing HRA with biopsy from November 1, 2011, to March 13, 2014, at a tertiary care HRA clinic. Data included demographics, medical history and comorbidities, HIV status and related measures (CD4 cell counts, HIV viral load, and use of highly active antiretroviral therapy), sexual orientation (when available), patient symptoms at initial presentation, physical examination findings, anal Papanicolaou (Pap) smear findings. High-resolution anoscopy diagnosis of high- vs low-grade dysplasia or no dysplasia. One hundred sixty-one HRA biopsy specimens (mean [SEM], 1.77 [0.11] biopsy specimens per patient) were obtained from 91 patients (mean [SEM] age, 45.7 [1.2] years; 61 men [67%]; 47 black patients [52%]; and 70 human immunodeficiency virus-positive patients [77%]). Twenty-seven patients (30%) had high-grade dysplasia, 26 had low-grade dysplasia (29%), and 38 had no dysplasia (42%). The majority of patients (63 [69%]) were asymptomatic (anal pain, 11 [12%]; bleeding, 14 [15%]; and pruritus, 10 [11%]). Forty-one patients (45%) presented with anal pain (odds ratio, 5.25; 95% CI, 1.44-21.82; P = .02), and patients with either high- or low-grade dysplasia were more likely to present with anal lesions on physical examination compared with patients without dysplasia (odds ratio, 4.34; 95% CI, 1.78-11.20; P = .002). Multivariable analysis suggested that anal pain was independently associated with high-grade dysplasia (odds ratio, 6.42; 95% CI, 1.18-43.3; P = .03). Anal dysplasia is a silent disease that is frequently asymptomatic. However, patients with anal

  14. Long-Term Outcome of Acetabular Reconstruction Using a Kerboull-Type Acetabular Reinforcement Device with Hydroxyapetite Granule and Structural Autograft for AAOS type II and III Acetabular Defects.

    PubMed

    Kim, Youngwoo; Tanaka, Chiaki; Kanoe, Hiroshi

    2015-10-01

    We evaluated the clinical results of the reconstruction of acetabular bone deficiency using hydroxyapatite (HA) granules and structural autografts supported by a Kerboull-type acetabular reinforcement device at a minimum of 10 years follow-up. Between 1993 and 2003, 40 consecutive THA revisions were performed in 37 patients with a mean age of 66.4 years. The mean follow-up period was 12.8 years. Radiologically, 5 hips failed, of which 2 were revised. The survival rate of the acetabular component at 10 years was 100% in type II defects and 94.9% in the type III defects, using acetabular revision for loosening as the end point. Acetabular reconstruction with HA granules, structural autografts and a Kerboull-type acetabular reinforcement device provided satisfactory clinical and radiological results at 12.8 years postoperatively.

  15. Arthroscopic Reduction and Transportal Screw Fixation of Acetabular Posterior Wall Fracture: Technical Note

    PubMed Central

    Park, Jin young; Kim, Che Keun; Huh, Soon Ho; Kim, Se Jin; Jung, Bo Hyun

    2016-01-01

    Acetabular fractures can be treated with variable method. In this study, acetabular posterior wall fracture was treated with arthroscopic reduction and fixation using cannulated screw. The patient recovered immediately and had a satisfactory outcome. In some case of acetabular fracture could be good indication with additional advantages of joint debridement and loose body removal. So, we report our case with technical note. PMID:27536654

  16. 21 CFR 888.3370 - Hip joint (hemi-hip) acetabular metal cemented prosthesis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Hip joint (hemi-hip) acetabular metal cemented... (hemi-hip) acetabular metal cemented prosthesis. (a) Identification. A hip joint (hemi-hip) acetabular metal cemented prosthesis is a device intended to be implanted to replace a portion of the hip...

  17. A Novel Approach for Treatment of Acetabular Fractures

    PubMed Central

    Xue, Zichao; Qin, Hui; Ding, Haoliang; An, Zhiquan

    2016-01-01

    Background There is no single approach that provides adequate exposure for treatment of all types of acetabular fractures. We describe our experience with an easier, relatively less invasive pubic symphysis approach (PSA) for the treatment of acetabular fractures. Material/Methods Between March 2011 and March 2012, fifteen patients with acetabular fracture underwent surgery using the PSA technique. Fracture reduction and treatment outcomes were assessed by clinical and radiological examination. Operation time, intraoperative blood loss and postoperative complications were documented. Results Mean operative time was 222±78 minutes. Average blood loss was 993±361 mL. Anatomical reduction was achieved in all patients. Minimum follow-up period was 31 months. Postoperative hypoesthesia in the area of innervation of the lateral femoral cutaneous nerve was reported in one patient, with spontaneous recovery at one month after surgery. No complications were reported during the follow-up period. At the most recent follow up, clinical outcomes were graded as “excellent” in six patients, “good” in eight patients and “fair” in one patient based on the modified Merle d’Aubigné-Postel score. Conclusions PSA appears to be a timesaving and safe approach for treatment of acetabular fractures that affords good visual access and allows for excellent fracture reduction. Our preliminary results revealed a much lower incidence of complications than traditional approaches, suggesting PSA is an alternative for treatment of acetabular fractures. PMID:27734825

  18. Experimental Investigation of the Robinson-Type Cup Anemometer

    NASA Technical Reports Server (NTRS)

    Brevoort, M J; Joyner, U T

    1936-01-01

    This report presents the results of wind tunnel tests on a Robinson-type anemometer. The investigation covered force measurements on individual cups, as well as static and dynamic torque measurements and calibrations on complete cup wheels. In the tests on individual cups 5 cup forms were used and in the measurements on complete cup wheels 4 cup wheels with 3 arm lengths for each cup wheel were tested. All the results are presented in graphical form.

  19. Effect of prior Salter or Chiari osteotomy on THA with developmental hip dysplasia.

    PubMed

    Tokunaga, Kenji; Aslam, Nadim; Zdero, Rad; Schemitsch, Emil H; Waddell, James P

    2011-01-01

    Controversy exists regarding the outcome of THA after prior pelvic osteotomy. We conducted a retrospective chart and radiographic review to obtain outcome measures for perioperative complications, acetabular and femoral component revisions, Harris hip score, and survivorship and compared these outcomes for patients presenting with developmental dysplasia of the hip treated surgically using THA with and without prior pelvic osteotomy. We performed 103 primary THAs in 87 patients with osteoarthritis secondary to developmental dysplasia of the hip with a minimum 3-year followup. Previous pelvic osteotomy was performed in 52 hips (Salter, 40; Chiari, nine; Salter and Chiari, three), and 51 hips had no previous surgery (control group). The pelvic osteotomy group did not have higher rates of femoral or acetabular intraoperative fracture or dislocation compared with the control group. The overall revision rate was 28.8% in the pelvic osteotomy group compared with 19.6% in the control group. The revision rate for aseptic loosening was 23.1% in the pelvic osteotomy group compared with 17.6% in the control group. Harris hip scores (range, 20-87) were not compromised, and overall survivorship rates 8 years postoperatively were not different at any time between the pelvic osteotomy (83.3%) and control (88.4%) groups. Prior pelvic osteotomy did not lead to a higher perioperative complication rate, higher revision rate, compromised Harris hip score, or shortened survivorship in eventual THA in developmental dysplasia of the hip. Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

  20. Effects of various anchoring components and loading conditions on primary stability of acetabular revision implant.

    PubMed

    Voigt, Christian; Schaller, Andreas; Klöhn, Carsten; Scholz, Roger

    2016-11-10

    In revision total hip arthroplasty, until today, orthopaedic surgeons are missing evidence-based guidelines on cementless acetabular cup fixation. 5 finite element models were generated featuring the following anchorage strategies: 1 short peg, 1 long peg, 2 long screws, 3 short screws and zero anchoring components for reference. The micromotions at the implant-bone interface were analyzed for 3 different loadcases, "Seated leg-crossing" (joint force 940 N, impingement force 750 N), "Normal gait" (joint force 1820 N), and "Stumbling" (joint force 4520 N). Within the same loadcase, percentages of interface area below 28 µm are nearly identical in all anchorage strategies. The average percentage of interface area below 28 µm is 31% for "Seated leg-crossing", 17% for "Normal gait", and 11% for "Stumbling". Maximal von Mises stresses in "Normal gait", for example, reach 12 MPa in the short peg, 48 MPa in the long peg, 15 MPa in 1 of the 2 long screws, and 85 MPa in 1 of the 3 short screws. Common orthopaedic practice, to use peg or screw fixation alternatively according to bone availability or other clinical aspects, can be confirmed. The short peg may be a good alternative to the long peg with regard to the preservation of bone stock. However, the current study implies that the extent of potential osseointegration depends less on the chosen anchorage strategy but strongly on postoperative loading conditions. Total hip patients should be instructed on adequate postoperative activities.

  1. Myometrial dysplasia (atypical myometrial hyperplasia).

    PubMed

    Cramer, Stewart F; Newcomb, Patricia M; Bonfiglio, Thomas A

    2007-04-01

    Although precursor lesions are well known for cervical and endometrial neoplasms, precursor lesions are not currently recognized for the most common tumor of the uterus-leiomyomas. Myometrial hyperplasia has been recently described and evaluated by morphometry, but its relationship to uterine leiomyomas has not been systematically explored. Myometrial dysplasia (atypical myometrial hyperplasia) has not been previously recognized. We herein report a case of myometrial dysplasia with immunostains for proliferation marker MIB-1 (Ki-67) and for p53. The paradoxical rarity of myometrial dysplasia is considered in comparison to the striking frequency of uterine leiomyomas.

  2. Fibrous dysplasia and cherubism

    PubMed Central

    Bhattacharya, Surajit; Mishra, RK

    2015-01-01

    Fibrous dysplasia (FD) is a non-malignant fibro-osseous bony lesion in which the involved bone/bones gradually get converted into expanding cystic and fibrous tissue. The underlying defect in FD is post-natal mutation of GNAS1 gene, which leads to the proliferation and activation of undifferentiated mesenchymal cells arresting the bone development in woven phase and ultimately converting them into fibro-osseous cystic tissue. Cherubism is a hereditary form of fibrous dysplasia in which the causative factor is transmission of autosomal dominant SH3BP2 gene mutation. The disease may present in two distinct forms, a less severe and limited monostotic form, and a more aggressive and more widespread polyostotic form. Polyostotic form may be associated with various endocrine abnormalities, which require active management apart from the management of FD. Management of FD is not free from controversies. While total surgical excision of the involved area and reconstruction using newer micro-vascular technique is the only definitive treatment available from the curative point of view, but this can be only offered to monostotic and very few polyostotic lesions. In polyostotic varieties on many occasions these radical surgeries are very deforming in these slow growing lesions and so their indication is highly debated. The treatment of cranio-facial fibrous dysplasia should be highly individualized, depending on the fact that the clinical behavior of lesion is variable at various ages and in individual patients. A more conservative approach in the form of aesthetic recontouring of deformed bone, orthodontic occlusal correction, and watchful expectancy may be the more accepted form of treatment in young patients. Newer generation real-time imaging guidance during recontouring surgery adds to accuracy and safety of these procedures. Regular clinical and radiological follow up is required to watch for quiescence, regression or reactivation of the disease process. Patients must be

  3. Tension band stabilisation of acetabular physeal fractures in four kittens.

    PubMed

    Langley-Hobbs, S J; Sissener, T R; Shales, C J

    2007-06-01

    The surgical repair of acetabular physeal fractures in four kittens using a screw and tension band technique is reported. This was an appropriate method for restoring articular congruency and improving pelvic alignment. All cases had an excellent outcome and full limb use following fracture repair. In kittens younger than 12 weeks, there is a possibility of premature fusion of the acetabular bone resulting in development of a deformed, shallow acetabulum and hip subluxation. However, surgery is still justified when there is pelvic canal narrowing to decrease the risk of future defecatory problems. Early implant removal in such young kittens may decrease the severity of deformity caused by premature physeal closure. In kittens of 16 weeks or older, the prognosis is good for normal acetabular development and implant removal is not necessary.

  4. Development of site-specific locking plates for acetabular fractures.

    PubMed

    Xu, Meng; Zhang, Li-Hai; Zhang, Ying-Ze; He, Chun-Qing; Zhang, Li-Cheng; Wang, Yan; Tang, Pei-Fu

    2013-05-01

    Site-specific locking plates have gained popularity for the treatment of fractures. However, the clinical use of a site-specific locking plate for acetabular fractures remains untested due to production limits. To design a universal site-specific locking plate for acetabular fractures, the 3-dimensional (3D) photographic records of 171 pelvises were retrospectively studied to generate a universal posterior innominate bone surface. Using 3D photographical processing software, the 3D coordinate system was reset according to bony landmarks and was scaled based on the acetabular diameter to allow a direct comparison between surfaces. The measured surface was separated into measurement units. At each measurement unit, the authors calculated the average z-axis values in all samples and obtained the 3D coordinate values of the point cloud that could be reconstructed into the universal surface. A plate was subsequently designed in 3D photographical processing software, and the orientation and distribution of locking screws was included. To manufacture a plate, the data were entered into Unigraphics NX version 6.0 software (Siemens PLM Software, Co, Ltd, Plano, Texas) and a CNC digital milling machine (FANUC Co, Ltd, Yamanashi, Japan). The resulting locking plate fit excellently with the reduced bone surface intraoperatively. Plate contouring was avoided intraoperatively. Universal 3.5-mm locking screws locked successfully into the plate, and their orientations were consistent with the design. No screw yielded to acetabular penetration. This method of designing a site-specific acetabular locking plate is practical, and the plates are suitable for clinical use. These site-specific locking plates may be an option for the treatment of acetabular fractures, particularly in elderly patients.

  5. Rationales for the Bernese approaches in acetabular surgery.

    PubMed

    Keel, M J B; Ecker, T M; Siebenrock, K-A; Bastian, J D

    2012-10-01

    To present two new approaches to acetabular surgery that were established in Berne, and which aim at enhanced visualization and anatomical reconstruction of acetabular fractures. The trochanteric flip osteotomy allows for surgical hip dislocation, and was introduced as a posterior approach for acetabular fracture management involving the posterior column and wall. For acetabular fractures predominantly involving the anterior column and the quadrilateral plate, the Pararectus approach is described. Full exposure of the hip joint, as provided by the trochanteric flip osteotomy, facilitates anatomical reduction of acetabular or femoral head fractures and safe positioning of the anterior column screw in transverse or T-shaped fractures. Additionally, the approach enables osteochondral transplantation as a salvage procedure for severe chondral femoral head damage and osteoplasty of an associated inadequate offset at the femoral head-neck junction. The Pararectus approach allows anatomical restoration with minimal access morbidity, and combines advantages of the ilioinguinal and modified Stoppa approaches. Utilization of the trochanteric flip osteotomy eases visualization of the superior aspect of the acetabulum, and enables the evaluation and treatment of chondral lesions of the femoral head or acetabulum and labral tears. Displaced fractures of the anterior column with a medialized quadrilateral plate can be addressed successfully through the Pararectus approach, in which surgical access is associated with minimal morbidity. However, long-term results following the two presented Bernese approaches are needed to confirm that in the treatment of complex acetabular fractures the rate of poor results in almost one-third of all cases (as currently yielded using traditional approaches) might be reduced by the utilization of the presented novel approaches.

  6. [Spondyloepiphyseal and metaphyseal dysplasia].

    PubMed

    Wirth, T

    2008-01-01

    Spondyloepiphyseal, metaphyseal and spondylometaphyseal dysplasias are a group of hereditary skeletal diseases, which lead to small stature, axial deformities of the lower extremities and spinal deformities. They differ in pathophysiology, heredity and in their clinical and radiologic appearance. The orthopaedic surgeon treats the spinal manifestations and the axial malalignment of the disease. Among the spinal deformities there are instabilities of the upper cervical spine as well as structural deformities like kyphosis and scoliosis. More frequently, the axial malalignment caused by congenital coxa vara, severe genu varum or genu valgum requires treatment. These deformities are managed by corrective osteotomies of the proximal femur, supracondylar or proximal tibial osteotomies around the knee and by temporary epiphyseodeses. Despite a high recurrence rate requiring repeated surgery the patients report great satisfaction with the treatment results. Well-timed orthopaedic treatment helps avoid or delay the inevitable long-term sequelae of untreated patients such as painful degenerative changes of the spine or early onset of severe osteoarthritis.

  7. Multiple epiphyseal dysplasia

    PubMed Central

    2009-01-01

    Background Multiple epiphyseal dysplasia (MED) is a common genetically and clinically heterogeneous skeletal dysplasia characterized by early-onset osteoarthritis, mainly in the hip and knee, and mild-to-moderate short stature. Here we report on a 6-generation MED family with 17 affected members. Method The clinical and radiographic data on the 12 affected members still living were scrutinized. A structured inquiry comprising state of health and MED-related symptoms since birth up to the present time and the osteoarthritis outcome (KOOS) questionnaire were sent to all living family members with MED. The 5 known gene loci for autosomal dominant MED were analyzed for linkage, using fluorescence-labeled microsatellite markers. Linkage was ascertained with markers close to the COL9A2 gene, which was analyzed for mutations by sequencing. Results We identified an exon 3 donor splice mutation in the COL9A2 gene in all affected family members. Clinical, radiographic, and questionnaire data from affected family members suggested that MED caused by COL9A2 mutations starts in early childhood with knee pain accompanied by delayed ossification of femoral epiphyses. The disease then either stabilizes during puberty or progresses with additional joints becoming affected; joint surgery might be necessary. The progression of the disease also affects muscles, with increasing atrophy, resulting in muscle fatigue and pain. Muscular atrophy has not been reported earlier in cases with COL9A2 mutations. Interpretation In a patient with clinically suspected or verified MED, it is important to perform DNA-based analysis to identify a possible disease-causing mutation. This information can be used to carry out genetic risk assessment of other family members and to achieve an early and correct diagnosis in the children. PMID:19995321

  8. Arthroscopic Technique for Acetabular Labral Reconstruction Using Iliotibial Band Autograft.

    PubMed

    Chahla, Jorge; Soares, Eduardo; Bhatia, Sanjeev; Mitchell, Justin J; Philippon, Marc J

    2016-06-01

    The dynamic function of the acetabular labrum makes it an important structure for both hip stability and motion. Because of this, injuries to the labrum can cause significant dysfunction, leading to altered hip kinematics. Labral repair is the gold standard for symptomatic labral tears to keep as much labral tissue as possible; however, in cases where the labrum has been injured to such a degree that it is either deficient or repair is not possible, arthroscopic labral reconstruction is preferred. This article describes our preferred approach for reconstruction of the acetabular labrum using iliotibial band autograft.

  9. Developmental dysplasia of the hip: usefulness of next generation genomic tools for characterizing the underlying genes - a mini review.

    PubMed

    Basit, S; Hannan, M A; Khoshhal, K I

    2016-07-01

    Developmental dysplasia of the hip (DDH) is one of the most common skeletal anomalies. DDH encompasses a spectrum of the disorder ranging from minor acetabular dysplasia to irreducible dislocation, which may lead to premature arthritis in later life. Involvement of genetic factors underlying DDH became evident when several studies reported chromosomal loci linked to DDH in families with multiple affected individuals. Moreover, using association studies, variants in genes involved in chondrogenesis and joint formation have been shown to be associated with DDH. At least, one study identified a pathogenic variant in the chemokine receptor gene in DDH. No genetic analysis has been reported or carried out in DDH patients from the Middle East. Here, we review the literature related to genetics of DDH and emphasized the usefulness of new generation technologies in identifying genetic variants underlying DDH in consanguineous families. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Lamp with a truncated reflector cup

    DOEpatents

    Li, Ming; Allen, Steven C.; Bazydola, Sarah; Ghiu, Camil-Daniel

    2013-10-15

    A lamp assembly, and method for making same. The lamp assembly includes first and second truncated reflector cups. The lamp assembly also includes at least one base plate disposed between the first and second truncated reflector cups, and a light engine disposed on a top surface of the at least one base plate. The light engine is configured to emit light to be reflected by one of the first and second truncated reflector cups.

  11. Guide to Understanding Fibrous Dysplasia

    MedlinePlus

    ... is usually involved. It can also result in cranial nerve problems. If the temporal bone is affected, the ... paralysis or dizziness. However, any of our 12 cranial nerves can be involved with fibrous dysplasia. The more ...

  12. Genetics Home Reference: osteoglophonic dysplasia

    MedlinePlus

    ... images. Premature fusion of certain bones in the skull (craniosynostosis) typically occurs in osteoglophonic dysplasia . The craniosynostosis ... in the medical literature as a tower-shaped skull , or a relatively mild version of a deformity ...

  13. Genetics Home Reference: campomelic dysplasia

    MedlinePlus

    ... a severe disorder that affects development of the skeleton, reproductive system, and other parts of the body. ... those that are important for development of the skeleton and reproductive organs. Most cases of campomelic dysplasia ...

  14. Genetics Home Reference: Kniest dysplasia

    MedlinePlus

    ... disorder of bone growth characterized by short stature (dwarfism) with other skeletal abnormalities and problems with vision ... for This Condition Kniest chondrodystrophy Kniest syndrome Metatropic dwarfism, type II Metatropic dysplasia type II Swiss cheese ...

  15. Ectodermal dysplasia with true anodontia

    PubMed Central

    Bala, Madhu; Pathak, Anuradha

    2011-01-01

    The hereditary condition known as ectodermal dysplasia is characterized by the absence or defect of two or more ectodermally derived structures. The most commonly observed forms of ectodermal dysplasia are the hidrotic and hypohidrotic types; discrimination is based on the absence or presence of sweat glands. A case of 8-year-old male child with hypohidrotic ectodermal dysplasia with complete anodontia of primary as well as secondary dentitions is presented. The child had a short stature, low intelligent quotient (I.Q.,), and was underweight. The patient experienced episodes of high fever, was intolerant to heat, and did not sweat. He exhibited smooth and dry skin, sparse light-colored eyebrows. Dental clinicians can be the first to diagnose ectodermal dysplasia due to the absence of teeth. PMID:22529591

  16. Genetics Home Reference: frontometaphyseal dysplasia

    MedlinePlus

    ... of a group of related conditions called otopalatodigital spectrum disorders, which also includes otopalatodigital syndrome type 1 , ... Frontometaphyseal dysplasia is distinguished from the other otopalatodigital spectrum disorders by the presence of joint deformities called ...

  17. Guide to Understanding Frontonasal Dysplasia

    MedlinePlus

    ... although most people with FND are of normal intelligence. Heart Rare cases of frontonasal dysplasia may be ... prognosis m any people with FND have normal intelligence and can expect a normal lifespan. how can ...

  18. Genetics Home Reference: gnathodiaphyseal dysplasia

    MedlinePlus

    ... be a variation of another bone disorder called osteogenesis imperfecta , which is also characterized by frequent bone fractures. ... considered to be a separate condition. Unlike in osteogenesis imperfecta , the fractures in gnathodiaphyseal dysplasia heal normally without ...

  19. [Acetabular defect reconstruction in revision surgery of the hip. Autologous, homologous or metal?].

    PubMed

    Gravius, S; Pagenstert, G; Weber, O; Kraska, N; Röhrig, H; Wirtz, D C

    2009-08-01

    The treatment of periprosthetic bone defects of the acetabulum is a therapeutic challenge in hip revision surgery. The aims are the biological reconstruction of osseous acetabular defects and the restoration of a load-bearing acetabular bone stock as well as restoring the physiological joint biomechanics and achieving primary and load-stable fixation of the revision graft in the vital pelvic bone. The biological reconstruction of the acetabular bone stock should include what is referred to as "down-grading" of the acetabular defect situation in case a repeat revision procedure becomes necessary.Nowadays, a large variety of grafts and reconstruction procedures are available for the reconstruction of acetabular defects. The choice of suitable materials (osseous or metallic) for the restoration of a load-bearing acetabular bone stock is currently the subject of controversial discussion.This article reviews the various options for the reconstruction of acetabular bone defects taking into consideration the current findings in the scientific literature.

  20. Acetabular screw head-induced ceramic acetabular liner fracture in cementless ceramic-on-ceramic total hip arthroplasty.

    PubMed

    Lee, Su Chan; Jung, Kwang Am; Nam, Chang Hyun; Kim, Tea Ho; Ahn, Nong Kyoum; Hwang, Seung Hyun

    2010-05-12

    Ceramic liner fractures are rare after ceramic-on-ceramic THA. This article describes a case of an early ceramic liner fracture caused by impingement with a tilted acetabular screw head 2 months after cementless ceramic-on-ceramic THA. A 59-year-old man underwent primary THA for avascular necrosis of his right femoral head. The implant used was an Osteonics Secur-Fit HA ceramic-on-ceramic bearing system. The metal shell was fixed with 1 cancellous bone screw. During the index procedure, the acetabular screw seemed tilted in the metal shell hole, but the liner was fully seated in the metal shell without difficulty. However, 2 months later he re-presented due to pain and crepitation in the right hip. Radiographs showed that the ceramic acetabular insert had fractured. At revision, ceramic insert had fractured into large and numerous comminuted fragments, and the acetabular screw head was slightly tilted and protruded over the inner surface of the metal shell, which had worn eccentrically. The ceramic inner head and metal shell were visibly intact. Because the metal shell-bone fixation was firm, a new identical design ceramic liner and head were fitted, and no adverse event has occurred since. This case suggests that a complete check of the inside of the shell should be made when using an acetabular screw and ceramic liner. In particular, the screw head must not be tilted or left proud of the inside surface of the shell. Correct acetabular screw direction and seating are essential to avoid detrimental clinical consequences. Copyright 2010, SLACK Incorporated.

  1. Cross-Modality Validation of Acetabular Surface Models Using 3-D Ultrasound Versus Magnetic Resonance Imaging in Normal and Dysplastic Infant Hips.

    PubMed

    Diederichs, Chad; Heath, Alana; Hareendranathan, Abhilash R; Zonoobi, Dornoosh; Kuntze, Gregor; Dulai, Sukhdeep; Mabee, Myles G; Ronsky, Janet L; Jaremko, Jacob L

    2016-09-01

    Current imaging diagnosis of developmental dysplasia of the hip (DDH) in infancy relies on 2-D ultrasound (US), which is highly operator-dependent. 3-D US offers more complete, and potentially more reliable, imaging of infant hip geometry. We sought to validate the fidelity of acetabular surface models obtained by 3-D US against those obtained concurrently by magnetic resonance imaging (MRI). 3-D US and MRI scans were performed on the same d in 20 infants with normal to severely dysplastic hips (mean age, 57 d; range 13-181 d). 3-D US was performed by two observers using a Philips VL13-5 probe. Coronal 3-D multi-echo data image combination (MEDIC) magnetic resonance (MR) images (1-mm slice thickness) were obtained, usually without sedation, in a 1.5 T Siemens unit. Acetabular surface models were generated for 40 hips from 3-D US and MRI using semi-automated tracing software, separately by three observers. For each hip, the 3-D US and MRI models were co-registered to overlap as closely as possible using Amira software, and the root mean square (RMS) distances between points on the models were computed. 3-D US scans took 3.2 s each. Inter-modality variability was visually minimal. Mean RMS distance between corresponding points on the acetabular surface at 3-D US and MRI was 0.4 ± 0.3 mm, with 95% confidence interval <1 mm. Mean RMS errors for inter-observer and intra-observer comparisons were significantly less for 3-D US than for MRI, while inter-scan and inter-modality comparisons showed no significant difference. Acetabular geometry was reproduced by 3-D US surface models within 1 mm of the corresponding 3-D MRI surface model, and the 3-D US models were more reliable. This validates the fidelity of 3-D US modeling and encourages future use of 3-D US in assessing infant acetabulum anatomy, which may be useful to detect and monitor treatment of hip dysplasia.

  2. Acetabular UHMWPE Survival and Wear Changes With Different Manufacturing Techniques

    PubMed Central

    Keating, E. Michael; Davis, Kenneth E.

    2010-01-01

    Background Polyethylene wear may be affected by the type of polyethylene resin, manufacturing technique, degree of thermal stabilization, and sterilization technique. Questions/purposes We therefore compared femoral head penetration into the PE and cup survival using the same cup system with different PE resins, manufacturing, and sterilization techniques. Methods Our study group consisted of 1912 THAs performed using the same uncemented cup and identical 28-mm cobalt-chrome heads. The polyethylene varied as follows: Group 1 (94 cups), GUR 4150 resin, ram-extruded, sterilized in air, no barrier packaging; Group 2 (74 cups), same as Group 1 but sterilized in argon; Group 3 (75 cups), Himont 1900 resin, compression-molded bar stock, sterilized in argon, no barrier packaging; Group 4 (620 cups), same as Group 3 except with barrier packing; Group 5 (711 cups), GUR 1050 resin, compression-molded bar stock, sterilized in argon gas with barrier packaging; and Group 6 (338 cups), GUR 1050 resin, compression-molded bar stock, sterilized in argon with barrier packaging, irradiated with 50 kGy, heated below melting temperature, machined, and finally placed in nonbarrier packaging with gas plasma sterilization. Minimum followup was 2 years (average, 7 years; range, 2–17 years). Results Femoral head penetration averaged 0.05 mm per year for Groups 5 and 6 and was substantially lower than for Groups 1 to 4. Cup survival was higher at seven years in Groups 3, 4, and 5, and at 10 years in group 4 when compared to groups 1, 2, and 3. Conclusions We observed lower FHP rates and higher cup survival with polyethylene machined from direct compression-molded bar stock, sterilized in argon gas, with barrier packaging. Level of Evidence Level III Therapeutic study. See Guidelines for Authors for a complete description of levels of evidence. PMID:20852973

  3. The Demographics of Canine Hip Dysplasia in the United States and Canada.

    PubMed

    Loder, Randall T; Todhunter, Rory J

    2017-01-01

    Canine hip dysplasia (CHD) is a common problem in veterinary medicine. We report the demographics of CHD using the entire hip dysplasia registry from the Orthopedic Foundation for Animals, analyzing differences by breed, sex, laterality, seasonal variation in birth, and latitude. There were 921,046 unique records. Each dog was classified using the American Kennel Club (AKC) and Fédération Cynologique Internationale (FCI) systems. Statistical analysis was performed with bivariate and logistic regression procedures. The overall CHD prevalence was 15.56%. The OR for CHD was higher in females (1.05), those born in spring (1.14) and winter (1.13), and those in more southern latitudes (OR 2.12). Within AKC groups, working dogs had the highest risk of CHD (OR 1.882) with hounds being the reference group. Within FCI groups, the pinscher/molossoid group had the highest risk of CHD (OR 4.168) with sighthounds being the reference group. The similarities between CHD and DDH are striking. Within DDH there are two different types, the typical infantile DDH and the late onset adolescent/adult acetabular dysplasia, with different demographics; the demographics of CHD are more similar to the later onset DDH group. Comparative studies of both disorders should lead to a better understanding of both CHD and DDH.

  4. The Demographics of Canine Hip Dysplasia in the United States and Canada

    PubMed Central

    Todhunter, Rory J.

    2017-01-01

    Canine hip dysplasia (CHD) is a common problem in veterinary medicine. We report the demographics of CHD using the entire hip dysplasia registry from the Orthopedic Foundation for Animals, analyzing differences by breed, sex, laterality, seasonal variation in birth, and latitude. There were 921,046 unique records. Each dog was classified using the American Kennel Club (AKC) and Fédération Cynologique Internationale (FCI) systems. Statistical analysis was performed with bivariate and logistic regression procedures. The overall CHD prevalence was 15.56%. The OR for CHD was higher in females (1.05), those born in spring (1.14) and winter (1.13), and those in more southern latitudes (OR 2.12). Within AKC groups, working dogs had the highest risk of CHD (OR 1.882) with hounds being the reference group. Within FCI groups, the pinscher/molossoid group had the highest risk of CHD (OR 4.168) with sighthounds being the reference group. The similarities between CHD and DDH are striking. Within DDH there are two different types, the typical infantile DDH and the late onset adolescent/adult acetabular dysplasia, with different demographics; the demographics of CHD are more similar to the later onset DDH group. Comparative studies of both disorders should lead to a better understanding of both CHD and DDH. PMID:28386583

  5. Cheaper Custom Shielding Cups For Arc Welding

    NASA Technical Reports Server (NTRS)

    Morgan, Gene E.

    1992-01-01

    New way of making special-purpose shielding cups for gas/tungsten arc welding from hobby ceramic greatly reduces cost. Pattern machined in plastic. Plaster-of-paris mold made, and liquid ceramic poured into mold. Cost 90 percent less than cup machined from lava rock.

  6. Cheaper Custom Shielding Cups For Arc Welding

    NASA Technical Reports Server (NTRS)

    Morgan, Gene E.

    1992-01-01

    New way of making special-purpose shielding cups for gas/tungsten arc welding from hobby ceramic greatly reduces cost. Pattern machined in plastic. Plaster-of-paris mold made, and liquid ceramic poured into mold. Cost 90 percent less than cup machined from lava rock.

  7. Osteofibrous dysplasia and adamantinoma.

    PubMed

    Most, Mathew J; Sim, Franklin H; Inwards, Carrie Y

    2010-06-01

    Osteofibrous dysplasia (OFD) is a rare, benign, fibro-osseous lesion that typically is seen within the cortex of the tibia in children. Adamantinoma (AD) is a rare, low-grade malignant primary bone tumor that occurs most often in the tibia and/or fibula of adolescent persons and young adults; however, it has been reported in other long bones, as well. Immunohistochemical and ultrastructural evidence has shown that the neoplastic cell in AD derives from an epithelial lineage. More recently, published reports have described another clinical entity-differentiated or OFD-like AD-that appears to lie between OFD and AD along a spectrum of disease. Controversy exists as to whether OFD is a precursor lesion to AD or whether OFD may be a residual lesion resulting from a spontaneously regressing AD. Management of OFD varies from observation to surgical intervention, depending on the age of the patient and the extent of the lesion. Management of AD requires surgical resection with wide margins, followed by appropriate reconstruction, to minimize the risk of local recurrence or metastasis.

  8. [Fibrous dysplasia of bone].

    PubMed

    Orcel, Philippe; Chapurlat, Roland

    2007-10-31

    Fibrous dysplasia of bone is a congenital non hereditary benign bone disease, where normal bone is replaced by a fibrous-like tissue with immature osteogenesis. Prevalence is difficult to estimate, due to frequent asymptomatic lesions. Bone lesions are mono- or polyostotic and may be associated with bone pain and fragility, leading to fractures. In some patients or bone sites, they are hypertrophic, responsible for neurological complications. Imaging and, when necessary, histology are the cornerstones of the diagnosis. A common molecular defect, i.e. activating mutations of the GNAS gene, encoding the a subunit of the Gs protein in target cells, is responsible for bone cell alterations as well as for the involvement of other cells/tissues bearing the same molecular defect (melanocytes, endocrine cells). These mutations affect only somatic cells and are therefore not hereditary: antenatal diagnosis is not appropriate for this disease and genetic counselling is not very useful, except for reassuring the patients. The conventional therapeutic approach is essentially symptomatic (pain killers) and orthopaedic (prevention and treatment of bone complications). Recent publications have focused attention on pamidronate, which rapidly relieves bone pain in most patients, and progressively increases bone mineralization in osteolytic areas in about half of the patients. Tubular phosphate wasting is common and should be treated with phosphate supplement and calcitriol. The prognosis should improve with therapeutic advances, but this remains to be properly evaluated.

  9. In vitro fatigue failure of cemented acetabular replacements: a hip simulator study.

    PubMed

    Zant, N P; Heaton-Adegbile, P; Hussell, J G; Tong, J

    2008-04-01

    Although hip simulators for in vitro wear testing of prosthetic materials used in total hip arthroplasty (THA) have been available for a number of years, similar equipment has yet to appear for endurance testing of fixation in cemented THA, despite considerable evidence of late aseptic loosening as one of the most significant failure mechanisms in this type of replacements. An in vitro study of fatigue behavior in cemented acetabular replacements has been carried out, utilizing a newly developed hip simulator. The machine was designed to simulate the direction and the magnitude of the hip contact force under typical physiological loading conditions, including normal walking and stair climbing, as reported by Bergmann et al. (2001, Hip 98, Freie Universitaet, Berlin). A 3D finite element analysis has been carried out to validate the function of the hip simulator and to evaluate the effects of boundary conditions and geometry of the specimen on the stress distribution in the cement mantle. Bovine pelvic bones were implanted with a Charnley cup, using standard manual cementing techniques. Experiments were carried out under normal walking and descending stairs loading conditions with selected load levels from a body weight of 75-125 kg. Periodically, the samples were removed from the test rigs to allow CT scanning for the purpose of monitoring damage development in the cement fixation. The hip simulator was found to be satisfactory in reproducing the hip contact force during normal walking and stair climbing, as reported by Bergmann et al. Finite element analysis shows that the stress distributions in the cement mantle and at the bone-cement interface are largely unaffected by the geometry and the boundary conditions of the model. Three samples were tested up to 17 x 10(6) cycles and sectioned post-testing for microscopic studies. Debonding at the bone-cement interface of various degrees in the posterior-superior quadrant was revealed in these samples, and the location

  10. A novel type II collagen gene mutation in a family with spondyloepiphyseal dysplasia and extensive intrafamilial phenotypic diversity

    PubMed Central

    Nakashima, Yasuharu; Sakamoto, Yuma; Nishimura, Gen; Ikegawa, Shiro; Iwamoto, Yukihide

    2016-01-01

    The purpose of this study was to describe a family with spondyloepiphyseal dysplasia caused by a novel type II collagen gene (COL2A1) mutation and the family’s phenotypic diversity. Clinical and radiographic examinations of skeletal dysplasia were conducted on seven affected family members across two generations. The entire coding region of COL2A1, including the flanking intron regions, was analyzed with PCR and direct sequencing. The stature of the subjects ranged from extremely short to within normal height range. Hip deformity and advanced osteoarthritis were noted in all the subjects, ranging from severe coxa plana to mild acetabular dysplasia. Atlantoaxial subluxation combined with a hypoplastic odontoid process was found in three of the subjects. Various degrees of platyspondyly were confirmed in all subjects. Genetically, a novel COL2A1 mutation (c.1349G>C, p.Gly450Ala) was identified in all the affected family members; however, it was not present in the one unaffected family member tested. We described a family with spondyloepiphyseal dysplasia and a novel COL2A1 mutation (c.1349G>C, p.Gly450Ala). Phenotypes were diverse even among individuals with the same mutation and within the same family. PMID:27274858

  11. Fourier analysis of the aerodynamic behavior of cup anemometers

    NASA Astrophysics Data System (ADS)

    Pindado, Santiago; Pérez, Imanol; Aguado, Maite

    2013-06-01

    The calibration results (the transfer function) of an anemometer equipped with several cup rotors were analyzed and correlated with the aerodynamic forces measured on the isolated cups in a wind tunnel. The correlation was based on a Fourier analysis of the normal-to-the-cup aerodynamic force. Three different cup shapes were studied: typical conical cups, elliptical cups and porous cups (conical-truncated shape). Results indicated a good correlation between the anemometer factor, K, and the ratio between the first two coefficients in the Fourier series decomposition of the normal-to-the-cup aerodynamic force.

  12. Developmental hip dysplasia in the Medici family: Giovanna from Austria (1548-1578) and her daughter Anna (1569-1584).

    PubMed

    Giuffra, Valentina; Fornaciari, Gino

    2013-01-01

    The skeletal remains of Giovanna from Austria (1548-1578), first wife of the Grand Duke of Tuscany Francesco I (1541-1587), and their daughter Anna (1569-1584) were exhumed from the Medici Chapels in the Basilica of S. Lorenzo in Florence and submitted to anthropological and paleopathological study. The superior portion of the acetabulum of Giovanna is sloping, and reveals bilateral acetabular dysplasia. The same defect is also present in Anna, together with sacral spina bifida occulta. In both women the anatomical abnormality is limited to a deformation in the roof of both acetabulae and the femoral heads continued to articulate normally within the hip joint. The presence of bilateral acetabular dysplasia in the skeletal remains of Giovanna and her daughter Anna can be explained by a series of risk factors to which the two Medici women were exposed: female sex, practice of swaddling in the first months of life, as well as scoliosis and pelvic deformity for Giovanna and family history for Anna.

  13. Vacuum extraction: a randomized controlled comparison of the New Generation cup with the original Bird cup.

    PubMed

    Carmody, F; Grant, A; Somchiwong, M

    1986-01-01

    A new design of vacuum extractor cup--'the New Generation cup'--has recently been introduced into clinical practice. Its major modification is a traction cord which passes around the rim of the cup for 180 degrees and is free to slide within the rim. Claims that this design 'enables the operator to pull obliquely without causing the cup to tilt' and thereby 'reduces failure rates, reduces the incidence of scalp trauma and increases operator confidence' have been evaluated in a randomized controlled trial. 123 women with singleton pregnancies of 37 completed weeks or more, with a cephalic presentation and for whom a decision to deliver by vacuum extraction had been taken, were randomly allocated to the 'New Generation' cup or BIRD's original vacuum extractor cup; 50 mm anterior and posterior cups were used in both groups as appropriate. The two groups were comparable at entry and delivered by obstetricians of similar status. The two types of cup were similar in respect of number of failures to deliver with the vacuum extractor, correct positioning of the cup, number of pulls required for delivery and time taken to expedite delivery. Cup detachments occurred in nine cases allocated to the 'New Generation' cup compared with four allocated to the original BIRD cup. The babies in the two groups were in similar condition at birth and sustained similar amounts of scalp trauma. Neonatal jaundice, both clinical and biochemical, was more common in babies delivered with the 'New Generation cup' and this was reflected in greater use of phototherapy in this group. Operators were equally divided in their preference of cup.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Novel fixation method of a periprosthetic fracture of the acetabulum using burr holes through the retained cup for locking screw fixation.

    PubMed

    Browne, James A; Weiss, David B

    2015-03-01

    The incidence of periprosthetic fractures of the acetabulum associated with a total hip arthroplasty is relatively low but may be increasing. Treatment options depend upon the stability of the prosthesis. In this case, we report an unusual fracture pattern where a large portion of posterior column remained osseointegrated to a displaced uncemented acetabular component and removal of the cup would have resulted in massive structural bone loss and potential pelvic discontinuity. A metal cutting burr was used to create additional screw holes in the cup to allow us to retain the original implant and also obtain fixation of the fracture. The patient had a good outcome at one year with a healed fracture, stable implant, and excellent function. To our knowledge, this technique has not been previously described and offers surgeons an approach to fix these challenging fractures.

  15. Cementless acetabular fixation in patients 50 years and younger at 10 to 18 years of follow-up.

    PubMed

    Teusink, Matthew J; Callaghan, John J; Warth, Lucian C; Goetz, Devon D; Pedersen, Douglas R; Johnston, Richard C

    2012-08-01

    The purpose of the study was to evaluate the 10- to 18-year follow-up of cementless acetabular fixation in patients 50 years and younger. We retrospectively reviewed a consecutive group of 118 patients (144 hips) in whom primary total hip arthroplasty had been performed by 2 surgeons using a cementless acetabular component. Two (1.4%) cementless acetabular components were revised because of aseptic loosening. Twenty-four hips (16.7%) were revised for any mechanical failure of the acetabular component mostly related to acetabular liner wear and osteolysis. The average linear wear rate was 0.19 mm per year, which was higher than our previous reports with cemented acetabular fixation. The fiber mesh ingrowth surface of the cementless acetabular component in this study was superior to cemented acetabular components in terms of fixation. However, the high rates of wear and osteolysis have led to poor overall acetabular component construct survivorship.

  16. Ectodermal Dysplasia: A Genetic Review

    PubMed Central

    Prashanth, S

    2012-01-01

    Abstract Ectodermal dysplasia is a rare hereditary disorder with a characteristic physiognomy. It is a genetic disorder affecting the development or function of the teeth, hair, nails and sweat glands. Depending on the particular syndrome ectodermal dysplasia can also affect the skin, the lens or retina of the eye, parts of the inner ear, the development of fingers and toes, the nerves and other parts of the body. Each syndrome usually involves a different combination of symptoms, which can range from mild to severe. The history and lessons learned from hypohidrotic ectodermal dysplasia (HED) may serve as an example for unraveling of the cause and pathogenesis of other ectodermal dysplasia syndromes by demonstrating that phenotypically identical syndromes can be caused by mutations in different genes (EDA, EDAR, EDARADD), that mutations in the same gene can lead to different phenotypes and that mutations in the genes further downstream in the same signaling pathway (NEMO) may modify the phenotype quite profoundly. The aim of this paper is to describe and discuss the etiology, genetic review, clinical manifestations and treatment options of this hereditary disorder. How to cite this article: Deshmukh S, Prashanth S. Ectodermal Dysplasia: A Genetic Review. Int J Clin Pediatr Dent 2012; 5(3):197-202. PMID:25206167

  17. [Wear and Roughness of Bearing Surface in Retrieved Polyethylene Bicon-Plus Cups].

    PubMed

    Ranuša, M; Gallo, J; Hobza, M; Vrbka, M; Nečas, D; Hartl, M

    2017-01-01

    PURPOSE OF THE STUDY By 7th December 2016, 4,755 Bicon-Plus cups in total were implanted in the Czech Republic. Some of them have been continuously re-operated, while the most frequent reason of failure is polyethylene wear and aseptic loosening. The present study is focused on surface analysis of retrieved polyethylene Bicon-Plus cups and the determination of the roughness of their bearing surfaces. MATERIAL AND METHODS In this study, we had 13 high molecular weight polyethylene cups with the average time in situ of 8.11 years (3.6-13.7, SD 3.2) before the retrieval. The study population was composed of 3 men, 10 women, with the mean age of 53.31 years. An optical scanning method, based on the principle of active triangulation, was used to determine wear rate. The rate of wear was identified by means of an obtained scan subsequently processed with the use of the GOM Inspect software. The roughness of surfaces was analysed with the application of Contour GT-X8 profiler using the principle of phase shifting interferometry. Measurements of surface topography of the retrieved cups were performed on the entire bearing surfaces. For the individual surface changes, a typical range of surface roughness, describing the particular wear character, was determined. By means of morphology analysis of the tested implants, three areas were identified: unworn area; area representing the worn part of the cup; and the area roughened by parallel grooving. The total surface roughness was evaluated as an arithmetic mean of the measured values. Subsequently, the values were sorted based on frequency and were classified into categories defining the particular wear mechanisms. RESULTS Wear rate of the retrieved acetabular cups was evaluated based on the wear direction vector and the size of linear wear. The average linear wear was equal to 0.13 mm/year (ranging from 0.26 to 2.29 mm/year), and the mean value of total volumetric material loss was 44.37 mm3/year (the range being from 51

  18. Advances in Skeletal Dysplasia Genetics.

    PubMed

    Geister, Krista A; Camper, Sally A

    2015-01-01

    Skeletal dysplasias result from disruptions in normal skeletal growth and development and are a major contributor to severe short stature. They occur in approximately 1/5,000 births, and some are lethal. Since the most recent publication of the Nosology and Classification of Genetic Skeletal Disorders, genetic causes of 56 skeletal disorders have been uncovered. This remarkable rate of discovery is largely due to the expanded use of high-throughput genomic technologies. In this review, we discuss these recent discoveries and our understanding of the molecular mechanisms behind these skeletal dysplasia phenotypes. We also cover potential therapies, unusual genetic mechanisms, and novel skeletal syndromes both with and without known genetic causes. The acceleration of skeletal dysplasia genetics is truly spectacular, and these advances hold great promise for diagnostics, risk prediction, and therapeutic design.

  19. Advances in Skeletal Dysplasia Genetics

    PubMed Central

    Geister, Krista A.; Camper, Sally A.

    2017-01-01

    Skeletal dysplasias result from disruptions in normal skeletal growth and development and are a major contributor to severe short stature. They occur in approximately 1/5,000 births, and some are lethal. Since the most recent publication of the Nosology and Classification of Genetic Skeletal Disorders, genetic causes of 56 skeletal disorders have been uncovered. This remarkable rate of discovery is largely due to the expanded use of high-throughput genomic technologies. In this review, we discuss these recent discoveries and our understanding of the molecular mechanisms behind these skeletal dysplasia phenotypes. We also cover potential therapies, unusual genetic mechanisms, and novel skeletal syndromes both with and without known genetic causes. The acceleration of skeletal dysplasia genetics is truly spectacular, and these advances hold great promise for diagnostics, risk prediction, and therapeutic design. PMID:25939055

  20. Epithelial dysplasia in oral cavity.

    PubMed

    Shirani, Samaneh; Kargahi, Neda; Razavi, Sayed Mohammad; Homayoni, Solmaz

    2014-09-01

    Among oral lesions, we encounter a series of malignant epithelial lesions that go through clinical and histopathologic processes in order to be diagnosed. Identifying these processes along with the etiology knowledge of these lesions is very important in prevention and early treatments. Dysplasia is the step preceding the formation of squamous cell carcinoma in lesions which have the potential to undergo dysplasia. Identification of etiological factors, clinical and histopathologic methods has been the topic of many articles. This article, reviews various articles presenting oral cavity dysplasia, new clinical methods of identifying lesions, and the immunohistochemical research which proposes various markers for providing more precise identification of such lesions. This article also briefly analyzes new treatment methods such as tissue engineering.

  1. Chondroectodermal Dysplasia: A Rare Syndrome

    PubMed Central

    Tahririan, Dana; Eshghi, Alireza; Givehchian, Pirooz; Tahririan, Mohammad Ali

    2014-01-01

    Chondroectodermal dysplasia (Ellis-Van Creveld syndrome) is a rare autosomal recessive congenital abnormality. This syndrome is characterized by a spectrum of clinical findings, among which chondrodystrophy, polydactyly, ectodermal dysplasia, and congenital cardiac anomalies are the most common. It is imperative to not overlook the cardiac complications in patients with this syndrome during dental procedures. The case presented here, although quite rare, was detected under normal conditions and can be alarming for dental care providers. Clinical reports outline the classical and unusual oral and dental manifestations, which help health care providers diagnose chondroectodermal dysplasia, and refer patients with this syndrome to appropriate health care professionals to receive treatment to prevent further cardiac complications and bone deformities. PMID:25628672

  2. Comparison of vacuum extraction delivery between the conventional metal cup and the new soft rubber cup.

    PubMed

    Srisomboon, J; Piyamongkol, W; Sahapong, V; Mongkolchaipak, S

    1998-07-01

    To compare the effectiveness and complications of vacuum extraction delivery between the conventional metal cup and the silicone rubber cup. A prospective randomized clinical trial of 90 pregnant women requiring assisted vaginal delivery who met the predetermined criteria for vacuum extraction were allocated to delivery by the Malstrom metal cup (46 cases) or the silicone rubber cup (44 cases). The two groups were similar in respect of age, parity gestational age and indications for assisted vaginal delivery. The mean and median numbers of tractions and time from cup application to delivery were not significantly different between the groups. The overall success rate was higher in the metal cup (89.1%) than in the rubber cup (79.5%) but not significantly different. The silicone cup was more likely to fail in cases of occiput posterior position, excessive caput, and severe degree of molding. There were no significant differences between groups in terms of Apgar scores, birth canal injury, and maternal blood loss. Scalp injuries occurred more frequently with the metal than with the rubber cup (P = 0.006). Vacuum extraction delivery with the silicone rubber cup is associated with reduced scalp injuries but has a greater tendency to fail when the fetus presents in occiput posterior position, has excessive caput or severe degree of molding.

  3. Prognostic radiographic factors in developmental dysplasia of the hip following Salter osteotomy.

    PubMed

    Chang, Chia-Hsieh; Yang, Wen-E; Kao, Hsuan-Kai; Lee, Wei-Chun; Shih, Chun-Hsiung; Kuo, Ken N

    2015-01-01

    Radiographic parameters for evaluating hip development are altered by Salter osteotomy, and their prognostic value require further validation. A total of 63 patients who underwent open reduction and Salter osteotomy for unilateral hip dysplasia were evaluated with Severin classification 10.8 years later. The initial first-year postoperative acetabular index, c/b ratio, head-teardrop distance, and head coverage were compared with the final outcome of Severin classification. Greater c/b ratio was significantly associated with later Severin class III hip. Using receiver operating characteristics curve, a c/b ratio greater than 0.72 at 6 months and 1 year postoperatively can predict the possibility of a class III hip in 30 and 60% of patients, respectively.

  4. Avascular necrosis and the Aberdeen splint in developmental dysplasia of the hip.

    PubMed

    Williams, P R; Jones, D A; Bishay, M

    1999-11-01

    Between January 1987 and December 1988 there were 7575 births in the Swansea maternity unit. Of these 823 (10.9%) were considered to be at 'high risk' for developmental dysplasia of the hip (DDH). Static ultrasound examination was performed in each case and the results classified on the basis of the method of Graf. A total of 117 type III-IV hips in 83 infants was splinted using the Aberdeen splint. Radiographs of these hips were taken at six and 12 months. Hilgenreiner's measurements of the acetabular angle were made in all cases and the development of the femoral capital epiphysis was assessed by measuring the epiphyseal area. The effect of splintage on the acetabular angle and the epiphyseal area between the normal and abnormal splinted hips was compared. Radiographs of 16 normal infants (32 normal unsplinted hips) were used as a control group. This cohort has now been followed up for a minimum of nine years. There have been no complications as a result of splintage. The failure rate was 1.7% or 0.25 per 1000 live births. No statistical difference was found when comparing the effect of splintage on the acetabular angle and epiphyseal area between normal and abnormal splinted hips and normal unsplinted hips. Our study has shown that while the Aberdeen splint had a definite but small failure rate, it was safe in that it did not produce avascular necrosis. The current conventional view that a low rate of splintage is always best is therefore brought into question if the Aberdeen splint is chosen for the management of neonatal DDH.

  5. Peri-acetabular bone mineral density in total hip replacement

    PubMed Central

    Gauthier, L.; Dinh, L.; Beaulé, P. E.

    2013-01-01

    Objectives To quantify and compare peri-acetabular bone mineral density (BMD) between a monoblock acetabular component using a metal-on-metal (MoM) bearing and a modular titanium shell with a polyethylene (PE) insert. The secondary outcome was to measure patient-reported clinical function. Methods A total of 50 patients (25 per group) were randomised to MoM or metal-on-polyethlene (MoP). There were 27 women (11 MoM) and 23 men (14 MoM) with a mean age of 61.6 years (47.7 to 73.2). Measurements of peri-prosthetic acetabular and contralateral hip (covariate) BMD were performed at baseline and at one and two years’ follow-up. The Western Ontario and McMaster Universities osteoarthritis index (WOMAC), University of California, Los Angeles (UCLA) activity score, Harris hip score, and RAND-36 were also completed at these intervals. Results At two years, only zone 1 showed a loss in BMD (-2.5%) in MoM group compared with a gain in the MoP group (+2.2%). Zone 2 showed loss in both groups (-2.2% for MoM; -3.9% for MoP) and zones 3 and 4 a gain in both groups (+0.1% for MoM; +3.3% for MoP). No other between-group differences were detected. When adjusting for BMD of the contralateral hip, no differences in BMD were observed. The only significant differences in functional scores at two years were higher UCLA activity (7.3 (sd 1.2) vs 6.1 (sd 1.5); p = 0.01) and RAND-36 physical function (82.1 (sd 13.0) vs 64.5 (sd 26.4); p = 0.02) for MoM bearings versus MoP. One revision was performed in the MoM group, for aseptic acetabular loosening at 11 months. Conclusions When controlling for systemic BMD, there were no significant differences between MoM and MoP groups in peri-acetabular BMD. However, increasing reports of adverse tissue reactions with large head MoM THR have restricted the use of the monoblock acetabular component to resurfacing only. PMID:23913361

  6. [Bronchopulmonary dysplasia: definitions and classifications].

    PubMed

    Sánchez Luna, M; Moreno Hernando, J; Botet Mussons, F; Fernández Lorenzo, J R; Herranz Carrillo, G; Rite Gracia, S; Salguero García, E; Echaniz Urcelay, I

    2013-10-01

    Bronchopulmonary dysplasia is the most common sequelae related to very low birth weight infants, mostly with those of extremely low birth weight. Even with advances in prevention and treatment of respiratory distress syndrome associated with prematurity, there is still no decrease in the incidence in this population, although a change in its clinical expression and severity has been observed. There are, however, differences in its frequency between health centres, probably due to a non-homogeneously used clinical definition. In this article, the Committee of Standards of the Spanish Society of Neonatology wishes to review the current diagnosis criteria of bronchopulmonary dysplasia to reduce, as much as possible, these inter-centre differences.

  7. Acetabular labral reconstruction with an iliotibial band autograft: outcome and survivorship analysis at minimum 3-year follow-up.

    PubMed

    Geyer, Mark R; Philippon, Marc J; Fagrelius, Theodore S; Briggs, Karen K

    2013-08-01

    Injury to the acetabular labrum results from multiple causes including femoroacetabular impingement, dysplasia, and acute trauma. The patient's labrum can be reconstructed utilizing an iliotibial band autograft that is tubularized and fixed to the acetabular rim, substituting for the patient's own labrum. Purpose/ The purpose of this study was to evaluate the midterm results of this technique with a follow-up from 3 to 6 years after reconstruction. The hypothesis was that midterm results would show excellent patient-reported outcomes and high patient satisfaction with outcome. Case series; Level of evidence, 4. A retrospective review of a prospectively collected registry was undertaken that identified 75 patients (76 hips) who underwent arthroscopic labral reconstruction using an iliotibial band autograft by a single surgeon from February 2005 to August 2008. Modified Harris Hip Score (mHHS), Hip Outcome Score (HOS), and patient satisfaction level (on a scale of 1-10) were recorded preoperatively and postoperatively annually. Survivorship analysis curves were created to evaluate the effectiveness of this technique. Among 76 hips, 19 progressed to total hip arthroplasty at an average of 28 months from the procedure. Mean survivor time (no arthroplasty) was 59.1 months (95% CI, 53.9-64.4). Follow-up on the surviving hips was available for 49 patients (86%) with a mean follow-up time of 49 months (range, 36-70 months). The mHHS significantly increased from a preoperative mean of 58.9 to the most recent follow-up score averaging 83 (P = .0001); HOS values in the sports and the activities of daily living subscales also increased significantly (P = .0001 and P = .001, respectively). Median patient satisfaction with outcome was 8. A joint space of ≤2 mm was found to be a poor prognostic factor for survival of the hip. Arthroscopic labral reconstruction using an iliotibial band autograft resulted in a survivorship of 56 months. Of the 76% of patients who did not require

  8. Acetabular revision with freeze-dried irradiated and chemically treated allograft: a minimum 5-year follow-up of 17 cases

    PubMed Central

    Caton, Jacques

    2007-01-01

    We reviewed the results of 17 consecutive revision total hip arthroplasties performed with the use of freeze-dried irradiated bone allograft in 15 patients. These allografts were used in conjunction with five Kerboull rings, two steel meshes and ten cemented isolated cups. All the patients have had a follow-up of at least 5 years. The patients were evaluated clinically and radiographically. No revisions were necessary and X-rays confirmed partial or total ingrowth of the allografts. In acetabular revision surgery, hip reconstruction can be successfully treated by freeze-dried irradiated and chemically treated allografts. Additional studies with longer term follow-up are necessary to confirm this outcome. PMID:17828537

  9. CLINICAL AND RADIOLOGICAL EVALUATION ON DEVELOPMENTAL HIP DYSPLASIA AFTER SALTER AND OMBRÉDANNE PROCEDURE.

    PubMed

    da Rocha, Válney Luiz; Thomé, André Luiz Coelho; da Silva Castro, Daniel Labres; de Oliveira, Leandro Zica; de Moraes, Frederico Barra

    2011-01-01

    To evaluate the clinical and radiological medium-term results from surgical treatment of developmental hip dysplasia through Salter innominate bone osteotomy and Ombrédanne femoral shortening. Fourteen patients were evaluated, with surgical treatment on 18 hips (seven right-side hips and eleven left-side hips) using the proposal technique, performed between 1998 and 2008. The Dutoit and Severin criteria were used respectively for clinical and radiographic evaluations. The average preoperative index for the seven right-side hips was 43.3° (40° to 50°), and this was corrected through surgery to an average of 31.57° (24° to 42°). The average preoperative index for the eleven left-side hips was 42.1° (36° to 56°), and this was corrected through surgery to an average of 30.36° (20° to 44°). There was a statistically significant difference between the preoperative and postoperative acetabular indexes, with P > 0.05. The clinical evaluation showed that there were seven excellent hips (38.9%), eight good ones (44.4%), three fair hips (16.7%) and no poor ones (0%). By grouping the hips rated good and excellent as satisfactory and those rated poor and fair as unsatisfactory, 83.3% of the results were seen to be favorable. There were no statistically significant correlations between occurrences of complications and patient age at the time of surgery or between complications and the preoperative acetabular index (p > 0.05). The complications observed consisted of one case each of subluxation, osteonecrosis and osteonecrosis together with subluxation. The combined procedure of Salter and Ombrédanne is a viable option for treating developmental hip dysplasia after patients have started to walk.

  10. Arthroplasty in patients with congenital hip dysplasia--early evaluation of a treatment method.

    PubMed

    Bożek, Marek; Bielecki, Tomasz; Nowak, Roman; Żelawski, Maciej

    2013-01-01

    Developmental hip dysplasia (DHD) is the most common cause of secondary hip osteoarthritis (OA). It often leads to OA in young, active and working adults. The aim of our study is to evaluate the results of THA in patients with DHD. Total hip arthroplasty was performed in 15 patients with DHD - 13 women (average age - 39) and 2 men (average age - 44) between June 2010 to June 2011. Patient's hips were estimated by Crowe classification to evaluate the severity of degenerative arthritis. Patients we reassessed with Harris Hip Score before and after the surgery. The mean preoperative score was 44.6 points, directly after surgery 62.4 pts., 6 months after 78.6 points. After artrhroplasty, improvement was noted in walking stairs without railing, walking without support, sitting on chair for more than 1 hour. Before the surgery average difference in limbs" length was 4 cm After the treatment it was reduced to 0.5 cm. Mean hip flexion was 40 ° before, 90 ° after the surgery, mean abduction was respectively 0° and 25°. Our study proves that total hip arthroplasty in patients with developmental dysplasia of hip helps to improve stability and mobility of joint and to reduce the pain. 1. In the type 1 and 2 according to Crow's classification, good clinical results may be achieved using standard prosthesis stem sizes and press-fit acebutalar component with possibly the smallest diameter providing stable placing. 2. In the case of ty pe III good results are observed using acetabular press-fit method for fixing, after reconstruction of bone defects with osteogenous bone graft. 3. The usage of big head dimensions gives beneficial effects on the osseointegration of the acetabular component and reduces the risk of dislocation. 4. A short follow-up period of the group of patients presented requires further prospective study to evaluate the long-term results.

  11. Stress fracture in acetabular roof due to motocross: case report.

    PubMed

    de Paiva Luciano, Alexandre; Filho, Nelson Franco

    2016-01-01

    One of the first steps to be taken in order to reduce sports injuries such as stress fractures is to have in-depth knowledge of the nature and extent of these pathological conditions. We present a case report of a stress fracture of the acetabular roof caused through motocross. This type of case is considered rare in the literature. The description of the clinical case is as follows. The patient was a 27-year-old male who started to have medical follow-up because of uncharacteristic pain in his left hip, which was concentrated mainly in the inguinal region of the left hip during motocross practice. After clinical investigation and complementary tests, he was diagnosed with a stress fracture of the acetabular roof.

  12. Late sciatic nerve axonotmesis following acetabular reconstruction plate.

    PubMed

    Moreta, J; Foruria, X; Labayru, F

    2016-01-01

    Sciatic nerve injuries associated with acetabular fractures can be post-traumatic, perioperative or postoperative. Late postoperative injury is very uncommon and can be due to heterotopic ossifications, muscular scarring, or implant migration. A case is presented of a patient with a previous transverse acetabular fracture treated with a reconstruction plate for the posterior column. After 17 years, she presented with progressive pain and motor deficit in the sciatic territory. Radiological and neurophysiological assessments were performed and the patient underwent surgical decompression of the sciatic nerve. A transection of the nerve was observed that was due to extended compression of one of the screws. At 4 years postoperatively, her pain had substantially diminished and the paresthesias in her leg had resolved. However, her motor symptoms did not improve. This case report could be relevant due to this uncommon delayed sciatic nerve injury due to prolonged hardware impingement.

  13. Multiobjective optimization of an electrostimulative acetabular revision system.

    PubMed

    Potratz, Carsten; Kluess, Daniel; Ewald, Hartmut; van Rienen, Ursula

    2010-02-01

    In this paper, we present a new approach for the enhancement of the bone proliferation rate by electrostimulation in the acetabular region. Based on the complex tissue structure in this area, the electric field distributions were computed by numerical means using a model based on high-resolution computed tomography scans of the acetabular area. This results in a complex, nonlinear, and discrete optimization problem. Therefore, an adapted algorithm was developed to reduce the computational effort in the order of several magnitudes. We divided the procedure into two stages: data extraction and a subsequent optimization process. The used optimization algorithm utilizes an evolutionary concept and a multidimensional definition of optimality for different, partly contradictive objective functions. Finally, we present first optimization results for different stimulation situations.

  14. Para-acetabular periarthritis calcarea: its radiographic manifestations.

    PubMed

    Kawashima, A; Murayama, S; Ohuchida, T; Russell, W J

    1988-01-01

    On retrospective reviews of radiographs, periarthritis calcarea was distinguished from os acetabula by interval radiographic progression and regression. Among 59 men and 51 women, there were 137 instances of para-acetabular calcifications and ossifications, which were morphologically classified as 58 discrete, 58 amorphous, and 21 segmented types. Correlations with other radiographic abnormalities, symptoms, signs, and laboratory abnormalities were sought, but not established. Out of 93 serially imaged opacities, 90 changed, including 37 of the 40 instances (92.5%) of the discrete type and 53 instances (100%) of the amorphous and segmented types--due to periarthritis calcarea. At least 43 of 90 densities were newly developed. Mean age at first detection was 47.7 years. Three of the discrete densities were unchanged and represented os acetabula. Thus, recognition of para-acetabular periarthritis calcarea is not only of academic importance; it can facilitate proper treatment as well.

  15. Acetabular augmentation for the treatment of unstable total hip arthroplasties.

    PubMed Central

    Nicholl, J. E.; Koka, S. R.; Bintcliffe, I. W.; Addison, A. K.

    1999-01-01

    Twenty-eight unstable total hip arthroplasties were treated with an acetabular augmentation wedge. Of the hips, 23 have had no further dislocations at a mean follow-up of 26 months. Five patients continued to dislocate and have needed further surgery. To our knowledge this is the largest reported series of acetabular augmentation with as good results as those of the most successful reported series of this technique, and a success rate comparable to other methods of treating recurrent dislocation. Careful patient selection, and using a thin augmentation wedge to avoid impingement, are important to the success of a technique which is a useful option in the management of recurrent dislocation. Images Figure 1 PMID:10364973

  16. Complications of acetabular fracture surgery in morbidly obese patients.

    PubMed

    Porter, Scott E; Russell, George V; Dews, Robert C; Qin, Zhen; Woodall, James; Graves, Matthew L

    2008-10-01

    To compare the early complications with operative treatment of acetabular fractures in morbidly obese (body mass index >or=40) patients when compared with all other patients. Retrospective review. University medical center. Four hundred thirty-five consecutive patients with acetabular fractures operatively treated by a single surgeon. Forty-one of these patients were morbidly obese (group 1) and were compared with the remaining patients (group 2). Group 2, therefore, included patients who were clinically overweight and obese. Operative repair of acetabular fracture. Outcome variables included patient positioning time, total operative time, estimated intraoperative blood loss, length of hospital stay, perioperative complications, and late complications. The average total operative time was 293 minutes for group 1 and 250 minutes (P = 0.008) for group 2. The hospital stay for group 1 averaged 26 days versus 15 days in group 2 (P < 0.01). There were 19 (46%) wound complications in group 1 compared with 49 (12%) in group 2 (P < 0.0001). Overall, there were complications in 26 of the 41 patients (63%) in group 1 and in 96 of the 394 patients (24%) in group 2. Group 1's relative risk of having a complication was 2.6 (95% confidence interval = 2.4-2.8) when compared with group 2. Our morbidly obese population had a statistically higher complication rate, longer operative times, and greater estimated intraoperative blood loss. The majority of complications were related primarily to wound healing problems and successfully controlled with aggressive approach to surgical debridement.

  17. Metaphyseal chondrodysplasia with ectodermal dysplasia

    SciTech Connect

    Jequier, S.; Bellini, F.; Mackenzie, D.A.

    1981-11-01

    The first case of metaphyseal chondrodysplasia with marked cupping of the metaphyses and cone epiphyses combined with complete alopecia was described in 1966 by Bellini. A second identical case was found in another Italian patient. Both show extremely early epiphyseal fusion. This is probably a new form of metaphyseal chondrodysplasia.

  18. Increased Mortality in Elderly Patients with Sarcopenia and Acetabular Fractures.

    PubMed

    Deren, Matthew E; Babu, Jacob; Cohen, Eric M; Machan, Jason; Born, Christopher T; Hayda, Roman

    2017-02-01

    Sarcopenia is a condition of clinically relevant loss of muscle mass and function. Acetabular fractures in elderly patients are common and difficult to treat. This study aimed to determine if sarcopenia is common in elderly patients with acetabular fractures and correlates with lower-energy mechanisms of injury, higher rates of complications, and higher mortality than patients with normal muscle mass. The Rhode Island Hospital Trauma Database was queried for patients who were ≥60 years of age from 2005 to 2014 using the International Classification of Diseases, Ninth Revision, code for closed acetabular fracture, 808.0. Charts were retrospectively reviewed for demographic data, operative intervention, mechanism of injury, mortality, comorbidities, and other factors. Computed tomography (CT) was used to determine the muscle cross-sectional area and to calculate the skeletal muscle index. The database revealed 192 patients coded for acetabular fracture; of these, 181 were correctly diagnosed. Ninety-nine patients had recorded body mass index (BMI) and adequate CT scans to measure the skeletal muscle index. Forty-two patients (42.4%) had sarcopenia, and 57 patients (57.6%) did not have sarcopenia. There were no significant differences in demographic characteristics between the groups with the exception of BMI and sex. BMI was higher in patients who did not have sarcopenia (31.7 kg/m) than it was in patients with sarcopenia (23.6 kg/m) (p < 0.001). Male sex was significantly greater (p = 0.0104) in patients with sarcopenia at 76.2% (32 of 42 patients) than in patients without sarcopenia at 50.9% (29 of 57 patients). Fractures in patients without sarcopenia were associated with a higher-energy mechanism of injury in 78.9% of cases compared with 52.4% of cases of patients with sarcopenia (p = 0.005). Sarcopenia was significantly associated (p = 0.0419) with increased 1-year mortality (28.6%) compared with the absence of sarcopenia (12.3%). This association was even

  19. Shape-based acetabular cartilage segmentation: application to CT and MRI datasets.

    PubMed

    Tabrizi, Pooneh R; Zoroofi, Reza A; Yokota, Futoshi; Nishii, Takashi; Sato, Yoshinobu

    2016-07-01

    A new method for acetabular cartilage segmentation in both computed tomography (CT) arthrography and magnetic resonance imaging (MRI) datasets with leg tension is developed and tested. The new segmentation method is based on the combination of shape and intensity information. Shape information is acquired according to the predictable nonlinear relationship between the U-shaped acetabulum region and acetabular cartilage. Intensity information is obtained from the acetabular cartilage region automatically to complete the segmentation procedures. This method is evaluated using 54 CT arthrography datasets with two different radiation doses and 20 MRI datasets. Additionally, the performance of this method in identifying acetabular cartilage is compared with four other acetabular cartilage segmentation methods. This method performed better than the comparison methods. Indeed, this method maintained good accuracy level for 74 datasets independent of the cartilage modality and with minimum user interaction in the bone segmentation procedures. In addition, this method was efficient in noisy conditions and in detection of the damaged cartilages with zero thickness, which confirmed its potential clinical usefulness. Our new method proposes acetabular cartilage segmentation in three different datasets based on the combination of the shape and intensity information. This method executes well in situations where there are clear boundaries between the acetabular and femoral cartilages. However, the acetabular cartilage and pelvic bone information should be obtained from one dataset such as CT arthrography or MRI datasets with leg traction.

  20. 21 CFR 888.3370 - Hip joint (hemi-hip) acetabular metal cemented prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint (hemi-hip) acetabular metal cemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3370 Hip joint (hemi-hip) acetabular metal cemented prosthesis. (a) Identification. A hip joint (hemi-hip)...

  1. 21 CFR 888.3370 - Hip joint (hemi-hip) acetabular metal cemented prosthesis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Hip joint (hemi-hip) acetabular metal cemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3370 Hip joint (hemi-hip) acetabular metal cemented prosthesis. (a) Identification. A hip joint (hemi-hip)...

  2. 21 CFR 888.3370 - Hip joint (hemi-hip) acetabular metal cemented prosthesis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Hip joint (hemi-hip) acetabular metal cemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3370 Hip joint (hemi-hip) acetabular metal cemented prosthesis. (a) Identification. A hip joint (hemi-hip)...

  3. 21 CFR 888.3370 - Hip joint (hemi-hip) acetabular metal cemented prosthesis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Hip joint (hemi-hip) acetabular metal cemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3370 Hip joint (hemi-hip) acetabular metal cemented prosthesis. (a) Identification. A hip joint (hemi-hip)...

  4. Skeletal dysplasias: A radiographic approach and review of common non-lethal skeletal dysplasias

    PubMed Central

    Panda, Ananya; Gamanagatti, Shivanand; Jana, Manisha; Gupta, Arun Kumar

    2014-01-01

    Skeletal dysplasias are not uncommon entities and a radiologist is likely to encounter a suspected case of dysplasia in his practice. The correct and early diagnosis of dysplasia is important for management of complications and for future genetic counselling. While there is an exhaustive classification system on dysplasias, it is important to be familiar with the radiological features of common dysplasias. In this article, we enumerate a radiographic approach to skeletal dysplasias, describe the essential as well as differentiating features of common non-lethal skeletal dysplasias and conclude by presenting working algorithms to either definitively diagnose a particular dysplasia or suggest the most likely differential diagnoses to the referring clinician and thus direct further workup of the patient. PMID:25349664

  5. Hip instability: a review of hip dysplasia and other contributing factors

    PubMed Central

    Kraeutler, Matthew J.; Garabekyan, Tigran; Pascual-Garrido, Cecilia; Mei-Dan, Omer

    2016-01-01

    Summary Background Hip instability has classically been associated with developmental dysplasia of the hip (DDH) in newborns and children. However, numerous factors may contribute to hip instability in children, adolescents, and adults. Purpose This review aims to concisely present the literature on hip instability in patients of all ages in order to guide health care professionals in the appropriate diagnosis and treatment of the various disorders which may contribute to an unstable hip. Methods We reviewed the literature on the diagnosis and surgical management of hip dysplasia and other causes of hip instability. Conclusions Multiple intra- and extra-articular variables may contribute to hip instability, including acetabular bony coverage, femoral torsion, femoroacetabular impingement, and soft tissue laxity. Physical examination and advanced imaging studies are essential to accurately diagnose the pathology contributing to a patient’s unstable hip. Conservative management, including activity modification and physical therapy, may be used as a first-line treatment in patients with intra-articular hip pathology. Patients who continue to experience symptoms of pain or instability should proceed with arthroscopic or open surgical treatment aimed at correcting the underlying pathology. Level of evidence V. PMID:28066739

  6. Ipsilateral Hip Dysplasia in Patients with Sacral Hemiagenesis: A Report of Two Cases

    PubMed Central

    Morimoto, Tadatsugu; Mawatari, Masaaki

    2015-01-01

    Sacral agenesis (SA) is a rare condition consisting of the imperfect development of any part of the sacrum. This paper describes two cases of the rare cooccurrence of ipsilateral SA and developmental dysplasia of the hip (DDH) and analyzes possible contributory factors for SA and DDH. Each of a 16-year-old female and 13-year-old female visited our hospital for left hip pain and limping. The findings of physical examinations showed a lower limb length discrepancy (left side) in both cases, as well as left hip pain without limitations of the range of motion or neurological deficits. Initial radiographs demonstrated left subluxation of the left hip with associated acetabular dysplasia and partial left sacral agenesis. MRI revealed a tethering cord with a fatty filum terminale, and periacetabular osteotomy combined with allogeneic bone grafting was performed. After the surgery, the patients experienced no further pain, with no leg length discrepancy and were able to walk without a limp, being neurologically normal with a normal left hip range of motion. The cooccurrence of SA and DDH suggests a plausible hypothesis to explain the embryogenic relationship between malformation of the sacrum and hip. PMID:25737792

  7. Sacroiliac joint dysfunction as a reason for the development of acetabular retroversion: a new theory.

    PubMed

    Cibulka, Michael T

    2014-05-01

    Acetabular retroversion has been recently implicated as an important factor in the development of femoral acetabular impingement and hip osteoarthritis. The proper function of the hip joint requires that the anatomic features of the acetabulum and femoral head complement one another. In acetabular retroversion, the alignment of the acetabulum is altered where it opens in a posterolaterally instead of anterior direction. Changes in acetabular orientation can occur with alterations in pelvic tilt (anterior/posterior), and pelvic rotation (left/right). An overlooked problem that alters pelvic tilt and rotation, often seen by physical therapists, is sacroiliac joint dysfunction. A unique feature that develops in patients with sacroiliac joint dysfunction (SIJD) is asymmetry between the left and right innominate bones that can alter pelvic tilt and rotation. This article puts forth a theory suggesting that acetabular retroversion may be produced by sacroiliac joint dysfunction.

  8. [Protrusio acetabuli. An update on the primary and secondary acetabular protrusion].

    PubMed

    Kindynis, P; Garcia, J

    1990-01-01

    Acetabular protrusion refers to intrapelvic displacement of the medial wall of the acetabulum and is defined as inward movement of the acetabular line so that the distance between this line and the laterally located ilioischial line is 3 mm or more in adult men and 6 mm or more in adult women. As discussed in this article, acetabular protrusion may be found in many bone disorders such as degenerative joint disease, Paget's disease, rheumatoid arthritis, ankylosing spondylitis, osteomalacia, Marfan's disease and as an effect of irradiation. Protrusio acetabuli appearing in absence of any recognizable cause is termed primary acetabular protrusion or Otto pelvis. Primary acetabular protrusion usually affects both hips in young to middle aged women with a history of diminished abduction, rotation and hip pain since puberty. Radiographically one notes a bilateral axial migration of the femoral head without joint space loss and with moderate degenerative changes.

  9. [Chlamydia trachomatis and cervix dysplasia].

    PubMed

    Alaniz Sánchez, A; Flores Martínez, A; León Vistrain, M C; Castañeda Cano, E

    1995-09-01

    Fifty patients between 18 and 70 years of age from Gynecology and Obstetrics Department, Hospital General "Gonzalo Castañeda" ISSSTE, were studied. Patients were referred for bearing positive cytology with mild, moderate and severe dysplasia; also intentional search for Chlamydia trachomatis was made, both in cytology as well as with the immunofluorescence method, and also directed biopsy. A positive association was found in 10 patients (20%) proving that Chlamydia trachomatis is a promotor and modifier of cervical atypia.

  10. Skeletal dysplasia in ancient Egypt.

    PubMed

    Kozma, Chahira

    2008-12-01

    The ancient Egyptian civilization lasted for over 3000 years and ended in 30 BCE. Many aspects of ancient Egyptian culture, including the existence of skeletal dysplasias, and in particular achondroplasia, are well known through the monuments and records that survived until modern times. The hot and dry climate in Egypt allowed for the preservation of bodies and skeletal anomalies. The oldest dwarf skeleton, the Badarian skeleton (4500 BCE), possibly represents an epiphyseal disorder. Among the remains of dwarfs with achondroplasia from ancient Egypt (2686-2190 BCE), exists a skeleton of a pregnant female, believed to have died during delivery with a baby's remains in situ. British museums have partial skeletons of dwarfs with achondroplasia, humeri probably affected with mucopolysaccharidoses, and a skeleton of a child with osteogenesis imperfecta. Skeletal dysplasia is also found among royal remains. The mummy of the pharaoh Siptah (1342-1197 BCE) shows a deformity of the left leg and foot. A mummified fetus, believed to be the daughter of king Tutankhamun, has scoliosis, spina bifida, and Sprengel deformity. In 2006 I reviewed the previously existing knowledge of dwarfism in ancient Egypt. The purpose of this second historical review is to add to that knowledge with an expanded contribution. The artistic documentation of people with skeletal dysplasia from ancient Egypt is plentiful including hundreds of amulets, statues, and drawing on tomb and temple walls. Examination of artistic reliefs provides a glance of the role of people with skeletal dysplasia and the societal attitudes toward them. Both artistic evidence and moral teachings in ancient Egypt reveal wide integration of individuals with disabilities into the society.

  11. Developmental dysplasia of the hip: A computational biomechanical model of the path of least energy for closed reduction.

    PubMed

    Zwawi, Mohammed A; Moslehy, Faissal A; Rose, Christopher; Huayamave, Victor; Kassab, Alain J; Divo, Eduardo; Jones, Brendan J; Price, Charles T

    2016-10-20

    This study utilized a computational biomechanical model and applied the least energy path principle to investigate two pathways for closed reduction of high grade infantile hip dislocation. The principle of least energy when applied to moving the femoral head from an initial to a final position considers all possible paths that connect them and identifies the path of least resistance. Clinical reports of severe hip dysplasia have concluded that reduction of the femoral head into the acetabulum may occur by a direct pathway over the posterior rim of the acetabulum when using the Pavlik harness, or by an indirect pathway with reduction through the acetabular notch when using the modified Hoffman-Daimler method. This computational study also compared the energy requirements for both pathways. The anatomical and muscular aspects of the model were derived using a combination of MRI and OpenSim data. Results of this study indicate that the path of least energy closely approximates the indirect pathway of the modified Hoffman-Daimler method. The direct pathway over the posterior rim of the acetabulum required more energy for reduction. This biomechanical analysis confirms the clinical observations of the two pathways for closed reduction of severe hip dysplasia. The path of least energy closely approximated the modified Hoffman-Daimler method. Further study of the modified Hoffman-Daimler method for reduction of severe hip dysplasia may be warranted based on this computational biomechanical analysis. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

  12. Hip dysplasia, pelvic obliquity, and scoliosis in cerebral palsy: a qualitative analysis using 3D CT reconstruction

    NASA Astrophysics Data System (ADS)

    Russ, Mark D.; Abel, Mark F.

    1998-06-01

    Five patients with cerebral palsy, hip dysplasia, pelvic obliquity, and scoliosis were evaluated retrospectively using three dimensional computed tomography (3DCT) scans of the proximal femur, pelvis, and lumbar spine to qualitatively evaluate their individual deformities by measuring a number of anatomical landmarks. Three dimensional reconstructions of the data were visualized, analyzed, and then manipulated interactively to perform simulated osteotomies of the proximal femur and pelvis to achieve surgical correction of the hip dysplasia. Severe deformity can occur in spastic cerebral palsy, with serious consequences for the quality of life of the affected individuals and their families. Controversy exists regarding the type, timing and efficacy of surgical intervention for correction of hip dysplasia in this population. Other authors have suggested 3DCT studies are required to accurately analyze acetabular deficiency, and that this data allows for more accurate planning of reconstructive surgery. It is suggested here that interactive manipulation of the data to simulate the proposed surgery is a clinically useful extension of the analysis process and should also be considered as an essential part of the pre-operative planning to assure that the appropriate procedure is chosen. The surgical simulation may reduce operative time and improve surgical correction of the deformity.

  13. Genetics Home Reference: CHST3-related skeletal dysplasia

    MedlinePlus

    ... Health Conditions CHST3-related skeletal dysplasia CHST3-related skeletal dysplasia Enable Javascript to view the expand/collapse ... PDF Open All Close All Description CHST3 -related skeletal dysplasia is a genetic condition characterized by bone ...

  14. Thanatophoric Dysplasia: A Case Report

    PubMed Central

    Jyoti; Jain, Rekha; Devendra

    2015-01-01

    Thanatophoric Dysplasia (TD) is a congenital, sporadic and the most lethal skeletal dysplasia caused by new mutation in the FGFR3 gene. At birth, it is characterized by shortening of the limbs (micromelia), small conical thorax, platyspondyly (flat vertebral bodies) and macrocephaly. TD is divided into two clinically defined subtypes: type I and II with some clinical overlap between the two subtypes. They can be differentiated by the skull shape and femur morphology. Ultrasound examination in the second trimester is often straight forward in diagnosing the congenital anomaly. We report a case of pre term fresh stillborn baby with dysmorphic facies, macrocephaly, micromelia with short stubby fingers and deep skin creases, narrow thorax and protuberant abdomen which delivered at our hospital. The ultrasound examination showed shortening of long bones with femur shaped like telephone receiver. Dysmorphic facial features and skeletal abnormalities in the baby lead us to make the diagnosis of TD type I. Because of the rarity of this condition we report this case of thanatophoric dysplasia with a short review of literature. PMID:26675119

  15. A plasma membrane template for macropinocytic cups

    PubMed Central

    Veltman, Douwe M; Williams, Thomas D; Bloomfield, Gareth; Chen, Bi-Chang; Betzig, Eric; Insall, Robert H; Kay, Robert R

    2016-01-01

    Macropinocytosis is a fundamental mechanism that allows cells to take up extracellular liquid into large vesicles. It critically depends on the formation of a ring of protrusive actin beneath the plasma membrane, which develops into the macropinocytic cup. We show that macropinocytic cups in Dictyostelium are organised around coincident intense patches of PIP3, active Ras and active Rac. These signalling patches are invariably associated with a ring of active SCAR/WAVE at their periphery, as are all examined structures based on PIP3 patches, including phagocytic cups and basal waves. Patch formation does not depend on the enclosing F-actin ring, and patches become enlarged when the RasGAP NF1 is mutated, showing that Ras plays an instructive role. New macropinocytic cups predominantly form by splitting from existing ones. We propose that cup-shaped plasma membrane structures form from self-organizing patches of active Ras/PIP3, which recruit a ring of actin nucleators to their periphery. DOI: http://dx.doi.org/10.7554/eLife.20085.001 PMID:27960076

  16. Three-dimensional acetabular orientation measurement in a reliable coordinate system among one hundred Chinese

    PubMed Central

    Zhang, Henghui; Wang, Yiping; Ai, Songtao; Chen, Xiaojun; Wang, Liao; Dai, Kerong

    2017-01-01

    Determining three-dimensional (3D) acetabular orientation is important for several orthopaedic scenarios, but the complex geometries of both pelvis and acetabulum make measurements of orientation unreliable. Acetabular orientation may also differ between the sexes or racial groups. We aimed to (1) establish and evaluate a novel method for measuring 3D acetabular orientation, (2) apply this new method to a large population of Chinese subjects, and (3) report relevant characteristics of native acetabular orientation in this population. We obtained computed tomography scans taken for non-orthopaedic indications in 100 Chinese subjects (50 male, 50 female). A novel algorithm tailored to segmentation of the hip joint was used to construct 3D pelvic models from these scans. We developed a surface-based method to establish a reliable 3D pelvic coordinate system and software to semi-automatically measure 3D acetabular orientation. Differences in various acetabular orientations were compared within and between subjects, between male and female subjects, and between our subjects and subjects previously reported by another group. The reported method was reliable (intraclass correlation coefficient >0.999). Acetabular orientations were symmetrical within subjects, but ranged widely between subjects. The sexes differed significantly in acetabular anteversion (average difference, 3.0°; p < 0.001) and inclination (1.5°; p < 0.03). Acetabular anteversion and inclination were substantially smaller among our Chinese subjects than previously reported for American subjects. Thus, our method was reliable and sensitive, and we detected sex differences in 3D acetabular orientation. Awareness of differences between the sexes and races is the first step towards better reconstruction of the hip joint for all individuals and could also be applied to other orthopaedic scenarios. PMID:28207829

  17. Genetics Home Reference: multiple epiphyseal dysplasia

    MedlinePlus

    ... health and development? More about Mutations and Health Inheritance Pattern Multiple epiphyseal dysplasia can have different inheritance patterns. This condition can be inherited in an autosomal ...

  18. Renal dysplasia in Beagle dogs: four cases.

    PubMed

    Bruder, Marc C; Shoieb, Ahmed M; Shirai, Norimitsu; Boucher, Germaine G; Brodie, Thomas A

    2010-12-01

    Anomalies of renal development comprise abnormalities in the amount of renal tissue (agenesis and hypoplasia); anomalies of renal position, form, and orientation; and renal dysplasia. There are previous reports of canine renal dysplasia in different breeds but none in the Beagle breed. This is the first report of renal dysplasia in this breed of dog. Morphologic descriptions of the range of microscopic features observed in four cases of renal dysplasia from preclinical studies in laboratory Beagle dogs are presented (including persistent primitive mesenchyme, persistence of metanephric ducts, asynchronous differentiation of nephrons, and atypical tubular epithelium), along with a basis for the classification of the lesion.

  19. Pelvic radiograph in skeletal dysplasias: An approach

    PubMed Central

    Jana, Manisha; Nair, Nikhil; Gupta, Arun K; Kabra, Madhulika; Gupta, Neerja

    2017-01-01

    The bony pelvis is constituted by the ilium, ischium, pubis, and sacrum. The pelvic radiograph is an important component of the skeletal survey performed in suspected skeletal dysplasia. Most of the common skeletal dysplasias have either minor or major radiological abnormalities; hence, knowledge of the normal radiological appearance of bony pelvis is vital for recognizing the early signs of various skeletal dysplasias. This article discusses many common and some uncommon radiological findings on pelvic radiographs along with the specific dysplasia in which they are seen; common differential diagnostic considerations are also discussed. PMID:28744080

  20. An updated review of the efficacy of cupping therapy.

    PubMed

    Cao, Huijuan; Li, Xun; Liu, Jianping

    2012-01-01

    Since 1950, traditional Chinese medicine (TCM) cupping therapy has been applied as a formal modality in hospitals throughout China and elsewhere in the world. Based on a previous systematic literature review of clinical studies on cupping therapy, this study presents a thorough review of randomized controlled trials (RCTs) to evaluate the therapeutic effect of cupping therapy. Six databases were searched for articles published through 2010. RCTs on cupping therapy for various diseases were included. Studies on cupping therapy combined with other TCM treatments versus non-TCM therapies were excluded. 135 RCTs published from 1992 through 2010 were identified. The studies were generally of low methodological quality. Diseases for which cupping therapy was commonly applied were herpes zoster, facial paralysis (Bell palsy), cough and dyspnea, acne, lumbar disc herniation, and cervical spondylosis. Wet cupping was used in most trials, followed by retained cupping, moving cupping, and flash cupping. Meta-analysis showed cupping therapy combined with other TCM treatments was significantly superior to other treatments alone in increasing the number of cured patients with herpes zoster, facial paralysis, acne, and cervical spondylosis. No serious adverse effects were reported in the trials. Numerous RCTs on cupping therapy have been conducted and published during the past decades. This review showed that cupping has potential effect in the treatment of herpes zoster and other specific conditions. However, further rigorously designed trials on its use for other conditions are warranted.

  1. An Updated Review of the Efficacy of Cupping Therapy

    PubMed Central

    Cao, Huijuan; Li, Xun; Liu, Jianping

    2012-01-01

    Background Since 1950, traditional Chinese medicine (TCM) cupping therapy has been applied as a formal modality in hospitals throughout China and elsewhere in the world. Based on a previous systematic literature review of clinical studies on cupping therapy, this study presents a thorough review of randomized controlled trials (RCTs) to evaluate the therapeutic effect of cupping therapy. Method Six databases were searched for articles published through 2010. RCTs on cupping therapy for various diseases were included. Studies on cupping therapy combined with other TCM treatments versus non-TCM therapies were excluded. Results 135 RCTs published from 1992 through 2010 were identified. The studies were generally of low methodological quality. Diseases for which cupping therapy was commonly applied were herpes zoster, facial paralysis (Bell palsy), cough and dyspnea, acne, lumbar disc herniation, and cervical spondylosis. Wet cupping was used in most trials, followed by retained cupping, moving cupping, and flash cupping. Meta-analysis showed cupping therapy combined with other TCM treatments was significantly superior to other treatments alone in increasing the number of cured patients with herpes zoster, facial paralysis, acne, and cervical spondylosis. No serious adverse effects were reported in the trials. Conclusions Numerous RCTs on cupping therapy have been conducted and published during the past decades. This review showed that cupping has potential effect in the treatment of herpes zoster and other specific conditions. However, further rigorously designed trials on its use for other conditions are warranted. PMID:22389674

  2. Fix and replace; an emerging paradigm for treating acetabular fractures

    PubMed Central

    Murphy, Colin G.; Carrothers, Andrew D.

    2016-01-01

    Summary Although technically challenging even for the experienced surgeon, simultaneous open reduction and internal fixation (ORIF) of acetabular fracture and total hip replacement (THR) have some potential advantages over the more traditional treatment options in specific patient subgroups; theoretically allowing immediate weight bearing and faster rehabilitation, reducing the cost of inpatient stay, and reducing the risks of early and late local complications associated with standard treatment for this type of injury. We review the evolution of the indications and techniques, outline the surgical challenges, and discuss implant options and outcomes for this treatment paradigm. PMID:28228787

  3. Penetration of a metallic femoral head through the acetabular shell.

    PubMed

    Sherman, Robert A; Damron, Timothy A

    2009-10-01

    Extensive wear of a metal-on-polyethylene total hip arthroplasty may rarely result in erosion of the metal-backed acetabular shell and penetration of the femoral head. We report on the case of an 85-year-old man who presented to the emergency department with an apparent dislocated total hip. He subsequently was discovered to have a periprosthetic fracture after an attempt at closed reduction of what was only discovered intraoperatively to be an irreducible transacetabular component central dislocation. Recognition of this rare complication may change clinical outcome.

  4. Sibs with mental retardation, supraorbital sclerosis, and metaphyseal dysplasia: frontometaphyseal dysplasia, craniometaphyseal dysplasia, or a new syndrome?

    PubMed Central

    Reardon, W; Hall, C M; Dillon, M J; Baraitser, M

    1991-01-01

    A brother and sister are presented with unusual facies, bilateral mixed hearing loss, mental retardation, and widespread radiological abnormalities. The clinical and radiological evidence for and against the two most likely diagnoses of frontometaphyseal dysplasia and craniometaphyseal dysplasia is considered. Images PMID:1956063

  5. Early results of the Bernese periacetabular osteotomy for symptomatic dysplasia in Charcot-Marie-Tooth disease.

    PubMed

    Stover, Michael D; Podeszwa, David A; De La Rocha, Adriana; Sucato, Daniel J

    2013-01-01

    Charcot-Marie-Tooth disease (CMTD) is one of the most common inherited neurologic disorders and can be associated with hip dysplasia. Little is known regarding outcomes of the PAO for patients with CMTD. Our purpose is to document the early results and complications of the PAO for hip dysplasia associated with CMTD. A two centre, retrospective clinical and radiographic review was performed. Demographic and surgical data were recorded. Pre- and postoperative lateral centre edge angle (LCEA), acetabular index (AI), ventral centre edge angle (VCEA), and Tönnis osteoarthritis grade were compared. Hips were classified according to Severin. The Harris Hip Score (HHS) and the Western Ontario and McMasters University (WOMAC) index documented self-reported function. Nineteen hips in 14 patients underwent PAO, mean age 16.2 (range 11.2-21 years). Thirteen concomitant procedures were performed, including seven proximal femoral osteotomies. Average follow-up was 3.4 years (range 0.9-8.5). Postoperative radiographic measurements significantly improved. Complications included femoral head AVN, transient complete bilateral peroneal nerve palsy, inferior rami fractures, and heterotopic ossification (Brooker stage 3). The HHS significantly improved from a mean 49.6 preoperatively to 82.2 at final follow-up of four patients. Seven subjects reported a mean postoperative WOMAC score of 94 (range 58.3-100). Most patients presented with severe dysplasia in the second decade of life. The PAO successfully corrected the radiographic abnormalities. Complications were common. The majority of patients reported improved outcomes, although seven showed signs of radiographic progression of osteoarthritis.

  6. Coffee to Go: Woman "Thinks" First Cup in 15 Years

    MedlinePlus

    ... turn Javascript on. Feature: NIBIB Robotics Coffee to Go: Woman "Thinks" First Cup in 15 Years Past ... Athlete Stands Again…On His Own! / Coffee to Go: Woman "Thinks" First Cup in 15 Years Spring ...

  7. Fast-response cup anemometer features cosine response

    NASA Technical Reports Server (NTRS)

    Frenzen, P.

    1968-01-01

    Six-cup, low-inertia anemometer combines high resolution and fast response with a unique ability to sense only the horizontal component of the winds fluctuating rapidly in three dimensions. Cup assemblies are fabricated of expanded polystyrene plastic.

  8. [Application of three-dimensional printing personalized acetabular wing-plate in treatment of complex acetabular fractures via lateral-rectus approach].

    PubMed

    Mai, J G; Gu, C; Lin, X Z; Li, T; Huang, W Q; Wang, H; Tan, X Y; Lin, H; Wang, Y M; Yang, Y Q; Jin, D D; Fan, S C

    2017-03-01

    Objective: To investigate reduction and fixation of complex acetabular fractures using three-dimensional (3D) printing technique and personalized acetabular wing-plate via lateral-rectus approach. Methods: From March to July 2016, 8 patients with complex acetabular fractures were surgically managed through 3D printing personalized acetabular wing-plate via lateral-rectus approach at Department of Orthopedics, the Third Affiliated Hospital of Southern Medical University. There were 4 male patients and 4 female patients, with an average age of 57 years (ranging from 31 to 76 years). According to Letournel-Judet classification, there were 2 anterior+ posterior hemitransverse fractures and 6 both-column fractures, without posterior wall fracture or contralateral pelvic fracture. The CT data files of acetabular fracture were imported into the computer and 3D printing technique was used to print the fractures models after reduction by digital orthopedic technique. The acetabular wing-plate was designed and printed with titanium. All fractures were treated via the lateral-rectus approach in a horizontal position after general anesthesia. The anterior column and the quadrilateral surface fractures were fixed by 3D printing personalized acetabular wing-plate, and the posterior column fractures were reduction and fixed by antegrade lag screws under direct vision. Results: All the 8 cases underwent the operation successfully. Postoperative X-ray and CT examination showed excellent or good reduction of anterior and posterior column, without any operation complications. Only 1 case with 75 years old was found screw loosening in the pubic bone with osteoporosis after 1 month's follow-up, who didn't accept any treatment because the patient didn't feel discomfort. According to the Matta radiological evaluation, the reduction of the acetabular fracture was rated as excellent in 3 cases, good in 4 cases and fair in 1 case. All patients were followed up for 3 to 6 months and all

  9. Clinical and radiographic medium‐term evaluation on patients with developmental dysplasia of the hip, who were submitted to open reduction, capsuloplasty and Salter osteotomy☆☆☆

    PubMed Central

    da Rocha, Válney Luiz; Marques, Guilherme Lima; da Silva, Leonardo Jorge; di Macedo Bernardes, Tiago Augusto; de Moraes, Frederico Barra

    2014-01-01

    Objective to evaluate the clinical and radiographic medium‐term results from surgical treatment of developmental dysplasia through open reduction, Salter et al.’s osteotomy and capsuloplasty. Methods 13 patients were evaluated, 13 hips treated surgically by the proposed technique between 2004 and 2011. A clinical and radiographic evaluation was conducted by Dutoit et al. and Severin et al. criteria, respectively. Results the acetabular preoperative index for the 13 surgically treated hips ranged from 27° to 50° (average of 36), and after surgical correction to 18.5° (10–28°), so that the evaluations of preoperative and postoperative acetabular indexes showed up significant statistic reduction (p < 0.05). Regarding the postoperative clinical evaluation, it was found: nine excellent hips (69.2%), three good ones (23.1%), no fair hips (0%) and a poor one (7.7%). In radiographic evaluation, it was found: six excellent hips (46.1%), three good ones (23.1%), no fair hips (0%) and four poor ones (30.8%). Therefore, favorable results were obtained (92.3%), with grouped hips with excellent and good ratings as satisfactory and with fair and bad ratings as unsatisfactory. It is also important to notice that there was no significance among occurrence of complications, the patient's age, the time of surgery and the preoperative acetabular index (p > 0.05). As complications occurred, it was found that three subluxations and a subluxation associated with avascular necrosis of the femoral head. Conclusion open reduction, Salter et al.’s osteotomy and capsuloplasty are seen to be a viable option for the treatment of developmental dysplasia of the hip, according to clinical and radiological medium‐term evaluations. PMID:26229772

  10. Axial Spondylometaphyseal Dysplasia Is Caused by C21orf2 Mutations.

    PubMed

    Wang, Zheng; Iida, Aritoshi; Miyake, Noriko; Nishiguchi, Koji M; Fujita, Kosuke; Nakazawa, Toru; Alswaid, Abdulrahman; Albalwi, Mohammed A; Kim, Ok-Hwa; Cho, Tae-Joon; Lim, Gye-Yeon; Isidor, Bertrand; David, Albert; Rustad, Cecilie F; Merckoll, Else; Westvik, Jostein; Stattin, Eva-Lena; Grigelioniene, Giedre; Kou, Ikuyo; Nakajima, Masahiro; Ohashi, Hirohumi; Smithson, Sarah; Matsumoto, Naomichi; Nishimura, Gen; Ikegawa, Shiro

    2016-01-01

    Axial spondylometaphyseal dysplasia (axial SMD) is an autosomal recessive disease characterized by dysplasia of axial skeleton and retinal dystrophy. We conducted whole exome sequencing and identified C21orf2 (chromosome 21 open reading frame 2) as a disease gene for axial SMD. C21orf2 mutations have been recently found to cause isolated retinal degeneration and Jeune syndrome. We found a total of five biallelic C21orf2 mutations in six families out of nine: three missense and two splicing mutations in patients with various ethnic backgrounds. The pathogenic effects of the splicing (splice-site and branch-point) mutations were confirmed on RNA level, which showed complex patterns of abnormal splicing. C21orf2 mutations presented with a wide range of skeletal phenotypes, including cupped and flared anterior ends of ribs, lacy ilia and metaphyseal dysplasia of proximal femora. Analysis of patients without C21orf2 mutation indicated genetic heterogeneity of axial SMD. Functional data in chondrocyte suggest C21orf2 is implicated in cartilage differentiation. C21orf2 protein was localized to the connecting cilium of the cone and rod photoreceptors, confirming its significance in retinal function. Our study indicates that axial SMD is a member of a unique group of ciliopathy affecting skeleton and retina.

  11. Decreased Lumbar Lordosis and Deficient Acetabular Coverage Are Risk Factors for Subchondral Insufficiency Fracture

    PubMed Central

    2016-01-01

    Subchondral insufficiency fracture (SIF) of the femoral head occurs in the elderly and recipients of organ transplantation. Osteoporosis and deficient lateral coverage of the acetabulum are known risk factors for SIF. There has been no study about relation between spinopelvic alignment and anterior acetabular coverage with SIF. We therefore asked whether a decrease of lumbar lordosis and a deficiency in the anterior acetabular coverage are risk factors. We investigated 37 patients with SIF. There were 33 women and 4 men, and their mean age was 71.5 years (59-85 years). These 37 patients were matched with 37 controls for gender, age, height, weight, body mass index and bone mineral density. We compared the lumbar lordosis, pelvic incidence, pelvic tilt, sacral slope, acetabular index, acetabular roof angle, acetabular head index, anterior center-edge angle and lateral center-edge angle. Lumbar lordosis, pelvic tilt, sacral slope, lateral center edge angle, anterior center edge angle, acetabular index and acetabular head index were significantly different between SIF group and control group. Lumbar lordosis (OR = 1.11), lateral center edge angle (OR = 1.30) and anterior center edge angle (OR = 1.27) had significant associations in multivariate analysis. Decreased lumbar lordosis and deficient anterior coverage of the acetabulum are risk factors for SIF as well as decreased lateral coverage of the acetabulum. PMID:27550496

  12. Prevalence of post-traumatic osteoarthritis in morbidly obese patients after acetabular fracture fixation.

    PubMed

    Lawyer, Tracye J; Jankowski, Jaclyn; Russell, George V; Stronach, Benjamin M

    2014-01-01

    Morbid obesity and osteoarthritis are conditions that place a significant burden on the US healthcare system. Acetabular fracture is a known cause of post-traumatic osteoarthritis (PTOA) and morbid obesity contributes to the development of osteoarthritis. This study aimed to determine the prevalence of PTOA in morbidly obese patients who underwent acetabular fracture fixation. A retrospective review of morbidly obese patients who underwent acetabular fracture repair was performed. Patient information included demographics, body mass index, patient age, and length of hospital stay. The prevalence of PTOA was determined by radiographic review with a minimum follow-up of 4 years. There were 299 acetabular fracture fixations performed from 2007 to 2012 at our institution and 39 of these were in morbidly obese patients. One patient was excluded due to preoperative osteoarthritis of the hip. Of the 38 patients, 26 (68%) went on to develop PTOA after acetabular fracture fixation. This is significantly higher than previously reported rates of PTOA after acetabular fracture fixation. There was a higher rate of PTOA in morbidly obese males compared with females (P=0.008). Morbid obesity appears to pose a significantly increased risk for the development of PTOA after fixation of acetabular fractures.

  13. Decreased Lumbar Lordosis and Deficient Acetabular Coverage Are Risk Factors for Subchondral Insufficiency Fracture.

    PubMed

    Jo, Woo Lam; Lee, Woo Suk; Chae, Dong Sik; Yang, Ick Hwan; Lee, Kyoung Min; Koo, Kyung Hoi

    2016-10-01

    Subchondral insufficiency fracture (SIF) of the femoral head occurs in the elderly and recipients of organ transplantation. Osteoporosis and deficient lateral coverage of the acetabulum are known risk factors for SIF. There has been no study about relation between spinopelvic alignment and anterior acetabular coverage with SIF. We therefore asked whether a decrease of lumbar lordosis and a deficiency in the anterior acetabular coverage are risk factors. We investigated 37 patients with SIF. There were 33 women and 4 men, and their mean age was 71.5 years (59-85 years). These 37 patients were matched with 37 controls for gender, age, height, weight, body mass index and bone mineral density. We compared the lumbar lordosis, pelvic incidence, pelvic tilt, sacral slope, acetabular index, acetabular roof angle, acetabular head index, anterior center-edge angle and lateral center-edge angle. Lumbar lordosis, pelvic tilt, sacral slope, lateral center edge angle, anterior center edge angle, acetabular index and acetabular head index were significantly different between SIF group and control group. Lumbar lordosis (OR = 1.11), lateral center edge angle (OR = 1.30) and anterior center edge angle (OR = 1.27) had significant associations in multivariate analysis. Decreased lumbar lordosis and deficient anterior coverage of the acetabulum are risk factors for SIF as well as decreased lateral coverage of the acetabulum.

  14. Spondyloepiphyseal dysplasia tarda in Turner syndrome.

    PubMed

    Massa, G; Vanderschueren-Lodeweyckx, M

    1989-11-01

    A girl with short stature is described in whom chromosomal analysis revealed a 45,X/46,XX mosaicism and in whom radiological investigations disclosed the diagnosis of X-linked spondyloepiphyseal dysplasia tarda. This is the first report of the occurrence of X-linked spondyloepiphyseal dysplasia tarda in a child with Turner syndrome.

  15. Intrapelvic protrusion of the acetabular component following total hip replacement.

    PubMed

    Salvati, E A; Bullough, P; Wilson, P D

    1975-09-01

    Protrusion of the acetabular component into the true pelvis following total hip replacement has occurred in 5 patients, 4 with severe rheumatoid arthritis and 1 with a destructive type of degenerative hip disease. Preoperatively all hips had severe protrusio acetabuli, a markedly thin acetabular medial wall and advanced osteoporosis. Four had a McKee-Farrar prosthesis, a metal-to-metal device with high frictional torque, particularly when the contact is equatorial, and no damping capacity against marginal impingement in the extreme range of motion. In order to reduce the incidence of intrapelvic protrusion, extreme care should be given to preserve the medial bone stock of the acetabulum, more so when it is already damaged or defective. If anchoring holes are used they should be restricted to the superior ilium, pubis and ischium and should not perforate the medial wall. Once loosening is present, reoperation is indicated to avoid progressive bone reabsorption by the abrasive motion of the loosened prosthesis, that might lead to irreparable bone loss. To reduce the stress transmitted to an already weakened acetabulum, select a total prosthetic device with low friction; fix it with acrylic cement in order to distribute the stress over a large surface; carefully orient both components to avoid marginal impingement; be certain to preserve the medial wall as much as possible and if it is already defective reinforce it by bone grafting and/or wire mesh.

  16. Automated measurement of anterior and posterior acetabular sector angles

    NASA Astrophysics Data System (ADS)

    Ibragimov, Bulat; Likar, Boštjan; Pernuš, Franjo; Vrtovec, Tomaž

    2012-03-01

    In this paper, we propose a segmentation algorithm by which anatomical landmarks on the pelvis are extracted from computed tomography (CT) images. The landmarks are used to automatically define the anterior (AASA) and posterior acetabular sector angles (PASA) describing the degree of hip misalignment. The center of each femoral head is obtained by searching for the point at which most intensity gradient vectors defined at edge points intersect. The radius of each femoral head is computed by finding the sphere, positioned at the center of the femoral head, for which the normalized sum of gradient vector magnitudes on the sphere surface is maximal. The anterior and posterior corners of each acetabulum are searched for on a curve representing the acetabulum and defined by dynamic programming. The femoral head centers and anterior and posterior corners are used to calculate the AASA and PASA. The algorithm was applied to CT images of 120 normal subjects and the results were compared to ground truth values obtained by manual segmentation. The mean absolute difference (+/- standard deviation) between the obtained and ground truth values was 1.3 +/- 0.3 mm for the femoral head centers and 2.1 +/- 1.3 degrees for the acetabular angles.

  17. Atypical periprosthetic acetabular fracture in long-term alendronate therapy

    PubMed Central

    Marongiu, Giuseppe; Capone, Antonio

    2016-01-01

    Summary Bisphosphonates have been commonly used in the treatment of osteoporosis, demonstrating its efficacy in fracture risk reduction. However, even if are generally safe and well tolerated, concerns have emerged about atypical fractures related to its prolonged use. Although atypical femoral fracture are more common, case reports demonstrated that even other skeletal areas can be involved by unusual pattern of fracture. We report a atypical acetabular periprosthetic fracture in a 83-year-old female patient after prolonged alendronate treatment for osteoporosis and isolated acetabular revision surgery. The patient underwent to clinical, bioumoral and radiological evaluation and all the history cases were fully reported. We believe this periprosthetic fracture, according to the available data, may have similar underlying pathology to atypical femoral fractures. Awareness of symptoms, in addition to a regular radiographic survey may facilitate early diagnosis and possible prevention of spontaneous periprosthetic fractures, in patients receiving bisphosphonate therapy beyond 5 years. The treatment of this atypical periprosthetic fracture should include both surgical than pharmacological therapy to obtained bone healing. PMID:28228784

  18. Atypical periprosthetic acetabular fracture in long-term alendronate therapy.

    PubMed

    Marongiu, Giuseppe; Capone, Antonio

    2016-01-01

    Bisphosphonates have been commonly used in the treatment of osteoporosis, demonstrating its efficacy in fracture risk reduction. However, even if are generally safe and well tolerated, concerns have emerged about atypical fractures related to its prolonged use. Although atypical femoral fracture are more common, case reports demonstrated that even other skeletal areas can be involved by unusual pattern of fracture. We report a atypical acetabular periprosthetic fracture in a 83-year-old female patient after prolonged alendronate treatment for osteoporosis and isolated acetabular revision surgery. The patient underwent to clinical, bioumoral and radiological evaluation and all the history cases were fully reported. We believe this periprosthetic fracture, according to the available data, may have similar underlying pathology to atypical femoral fractures. Awareness of symptoms, in addition to a regular radiographic survey may facilitate early diagnosis and possible prevention of spontaneous periprosthetic fractures, in patients receiving bisphosphonate therapy beyond 5 years. The treatment of this atypical periprosthetic fracture should include both surgical than pharmacological therapy to obtained bone healing.

  19. Improved analytical method to study the cup anemometer performance

    NASA Astrophysics Data System (ADS)

    Pindado, Santiago; Ramos-Cenzano, Alvaro; Cubas, Javier

    2015-10-01

    The cup anemometer rotor aerodynamics is analytically studied based on the aerodynamics of a single cup. The effect of the rotation on the aerodynamic force is included in the analytical model, together with the displacement of the aerodynamic center during one turn of the cup. The model can be fitted to the testing results, indicating the presence of both the aforementioned effects.

  20. Ectodermal dysplasia and abnormal thumbs.

    PubMed

    Lucky, A W; Esterly, N B; Tunnessen, W W

    1980-05-01

    Two unrelated children, a girl and a boy, with alopecia, anomalous cutaneous pigmentation, abnormal thumbs, and endocrine disorders, including short stature and delayed bone age in one patient and juvenile onset diabetes mellitus in the other, are described. In one instance, the mother and the maternal grandmother had similar abnormalities, although of a less severe nature. Both children had normal nails and no unusual susceptibility to infections. We believe these two patients represent a previously undescribed syndrome of ectodermal dysplasia that may be inherited as an autosomal-dominant trait.

  1. Ectodermal dysplasia in identical twins

    PubMed Central

    Puttaraju, Gurkar Haraswarupa; Visveswariah, Paranjyothi Magadi

    2013-01-01

    Hereditary hypohidrotic ectodermal dysplasia (HED) is typically inherited as an X-linked recessive trait, characterized by deformity of at least two or more of the ectodermal structures - hair, teeth, nails and sweat glands. Two cases of hereditary HED involving identical male twins, is being documented for the rarity of its occurrence with special attention given to genetics, pathophysiology, clinical, intraoral manifestations and to the methods to improve the masticatory function, the facial esthetics and psychology of patients affected by this disease. PMID:23956595

  2. Conservative Management of Hip Dysplasia.

    PubMed

    Harper, Tisha A M

    2017-07-01

    Hip dysplasia (HD) is a common orthopedic condition seen in small animal patients that leads to osteoarthritis of the coxofemoral joint. The disease can be managed conservatively or surgically. The goals of surgical treatment in the immature patient are to either prevent the clinical signs of HD or to prevent or slow the progression of osteoarthritis. In mature patients surgery is used as a salvage procedure to treat debilitating osteoarthritis. Conservative management can be used in dogs with mild or intermittent clinical signs and includes nutritional management and weight control, exercise modification, physical rehabilitation, pain management and disease-modifying agents. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. From Baby Bottle to Cup: Choose Training Cups Carefully, Use Them Temporarily

    MedlinePlus

    ... production increases during a meal and helps neutralize acid production and rinse food particles from the mouth.) If your child is thirsty between meals, offer water in the cup. Do not let your child ...

  4. Diagnosis and management of gastric dysplasia

    PubMed Central

    Sung, Jae Kyu

    2016-01-01

    Gastric dysplasia is a neoplastic lesion and a precursor of gastric cancer. The Padova, Vienna, and World Health Organization classifications were developed to overcome the discrepancies between Western and Japanese pathologic diagnoses and to provide a universally accepted classification of gastric epithelial neoplasia. At present, the natural history of gastric dysplasia is unclear. Much evidence suggests that patients with high-grade dysplasia are at high risk of progression to carcinoma or synchronous carcinoma. Therefore, endoscopic resection is required. Although patients with low-grade dysplasia have been reported to be at low risk of progression to carcinoma, due to the marked histologic discrepancies between forceps biopsy and endoscopic specimens, endoscopic resection for this lesion is recommended, particularly in the presence of other risk factors (large size; depressed gross type; surface erythema, unevenness, ulcer, or erosion; and tubulovillous or villous histology). Helicobacter pylori eradication in patients with dysplasia after endoscopic resection appear to reduce the incidence of metachronous lesions. PMID:26932397

  5. Nuclear Physics in a Coffee Cup

    ERIC Educational Resources Information Center

    Higbie, J.

    1974-01-01

    Discusses physical phenomena which can be demonstrated by using a coffee cup, involving the short-range field, alpha-particle scattering, standing waves, and Bohr's closed electron orbits. Indicates that observation of the physics of the classroom in everyday objects can attract student interest in physics learning. (CC)

  6. Fast Faraday Cup With High Bandwidth

    SciTech Connect

    Deibele, Craig E

    2006-03-14

    A circuit card stripline Fast Faraday cup quantitatively measures the picosecond time structure of a charged particle beam. The stripline configuration maintains signal integrity, and stitching of the stripline increases the bandwidth. A calibration procedure ensures the measurement of the absolute charge and time structure of the charged particle beam.

  7. Recycling disposable cups into paper plastic composites.

    PubMed

    Mitchell, Jonathan; Vandeperre, Luc; Dvorak, Rob; Kosior, Ed; Tarverdi, Karnik; Cheeseman, Christopher

    2014-11-01

    The majority of disposable cups are made from paper plastic laminates (PPL) which consist of high quality cellulose fibre with a thin internal polyethylene coating. There are limited recycling options for PPLs and this has contributed to disposable cups becoming a high profile, problematic waste. In this work disposable cups have been shredded to form PPL flakes and these have been used to reinforce polypropylene to form novel paper plastic composites (PPCs). The PPL flakes and polypropylene were mixed, extruded, pelletised and injection moulded at low temperatures to prevent degradation of the cellulose fibres. The level of PPL flake addition and the use of a maleated polyolefin coupling agent to enhance interfacial adhesion have been investigated. Samples have been characterised using tensile testing, dynamic mechanical analysis (DMA) and thermogravimetric analysis. Use of a coupling agent allows composites containing 40 wt.% of PPL flakes to increase tensile strength of PP by 50% to 30 MPa. The Young modulus also increases from 1 to 2.5 GPa and the work to fracture increases by a factor of 5. The work demonstrates that PPL disposable cups have potential to be beneficially reused as reinforcement in novel polypropylene composites.

  8. 21 CFR 872.6290 - Prophylaxis cup.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Prophylaxis cup. 872.6290 Section 872.6290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... agent and the user applies it to the teeth to remove debris. (b) Classification. Class I...

  9. 21 CFR 872.6290 - Prophylaxis cup.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Prophylaxis cup. 872.6290 Section 872.6290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... agent and the user applies it to the teeth to remove debris. (b) Classification. Class I...

  10. 21 CFR 872.6290 - Prophylaxis cup.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Prophylaxis cup. 872.6290 Section 872.6290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... agent and the user applies it to the teeth to remove debris. (b) Classification. Class I...

  11. 21 CFR 872.6290 - Prophylaxis cup.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prophylaxis cup. 872.6290 Section 872.6290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... agent and the user applies it to the teeth to remove debris. (b) Classification. Class I...

  12. 21 CFR 872.6290 - Prophylaxis cup.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Prophylaxis cup. 872.6290 Section 872.6290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... agent and the user applies it to the teeth to remove debris. (b) Classification. Class I...

  13. [Custom cementless stem for osteoarthritis following developmental hip dysplasia].

    PubMed

    Flecher, X; Argenson, J N; Parratte, S; Ryembault, E; Aubaniac, J M

    2006-06-01

    Arthroplasty in developmental dysplasia of the hip joint raises technical problems related to the anatomy and age of the young patient. The purpose of this work was to report results obtained with a custom-designed cementless stem. This study included 257 hips reviewed at mean 82 months (range 43-162 months). Mean patient age was 55 years (17-78), mean weight 67 kg (42-118), and mean height 164 cm (147-190). A standard imaging protocol was performed for all patients: AP pelvis in reclining position, AP and lateral views of healthy and pathological hip, AP view of entire lower limb in standing position, computed tomography of lower limb. La position of the greater trochanter and the lengthening necessary was determined from the preoperative films. Stem integration and migration as well as osteolysis were studied postoperatively. Femoral anteversion and the anteroposterior diameter of the paleoacetabulum were measured on the superposed computed tomographic images. Surgery was performed via a Watson-Jones approach to insert a noncemented cup hooked in the obturator foramen and implanted in the paleoacetabulum. The femur endomedullary cavity was prepared with a ream having the form of the definitive stem and the prosthetic neck was custom fit to match the desired lever arm and anteversion. The series included 174 cases of dysplasia and 83 dislocations, 39% stage 1, 30% stage 2, 14% stage 3 and 17% stage 4. Mean lengthening was 39 mm. The mean helitorsion was 28 +/- 16 degrees and the mean anteroposterior diameter of the acetabulum was 51 mm. On average, the alpha correction in the prosthetic neck was -13.4 degrees (-71 degrees to +37 degrees). The Postel-Merle-d'Aubigné score improved from 10.4 points preoperatively to 16.7 points at last follow-up. Postoperative x-rays showed signs of osteointegration in 88% of cases, osteolysis in 5% and one case of stem impaction. Ten hips (3.9%) required revision for replacement (7 for an aseptic problem and 3 for sepsis

  14. The fate of lateral femoral cutaneous nerve after surgical reduction of developmental dysplasia of the hip: preliminary results.

    PubMed

    Şeşen, Hakan; Çatma, Mehmet F; Demirkale, İsmail; Karaduman, Mert; Altay, Murat; Korucu, Osman

    2016-05-01

    This study aimed to determine the fate of the lateral femoral cutaneous nerve (LFCN) after anterior reduction of the hip with or without pelvic or proximal femoral osteotomy for acetabular dysplasia. Using the antidromic technique, recording the response using standard electromyography equipment, evaluation was made of the LFCN in 36 hips of 24 patients (18 female and six male). The response was absent in six patients (25%) and nine patients (37.5%) had a somatosensory evoked potential latency greater than 40 ms. There was no relationship between somatosensory evoked potential latency or absent response with the type of incision or procedure (P=0.229 and 0.794, respectively). LFCN injury after anterior open reduction of the hip has an unexpectedly high incidence in the young paediatric age group. Exposure of the nerve during surgery can negatively affect the nerve nutrition leading to neuropraxia.

  15. Biorobotic adhesion in water using suction cups.

    PubMed

    Bandyopadhyay, Promode R; Hrubes, J Dana; Leinhos, Henry A

    2008-03-01

    Echeneid fish, limpets and octopi use suction cups for underwater adhesion. When echeneid fish use suckers to 'hitch a ride' on sharks (which have riblet-patterned skins), the apparent absence of any pump or plumbing may be an advantage over biorobotic suction cups. An intriguing question is: How do they achieve seemingly persistent leak-free contact at low energy cost over rough surfaces? The design features of their suckers are explored in a biorobotic context of adhesion in water over rough surfaces. We have carried out experiments to compare the release force and tenacity of man-made suction cups with those reported for limpets and echeneid fish. Applied tensile and shear release forces were monotonically increased until release. The effects of cup size and type, host surface roughness, curvature and liquid surface tension have been examined. The flow of water in the sharkskin-like host surface roughness has been characterized. The average tenacity is 5.28 N cm(-2) (sigma = 0.53 N cm(-2), N = 37) in the sub-ambient pressure range of 14.6-49.0 kPa, in man-made cups for monotonically increasing applied release force. The tenacity is lower for harmonically oscillating release forces. The dynamic structural interactions between the suction cup and the oscillating applied forcing are discussed. Inspired by the matching of sharkskin riblet topology in echeneid fish suckers, it was found that biorobotic sealed contact over rough surfaces is also feasible when the suction cup makes a negative copy of the rough host surface. However, for protracted, persistent contact, the negative topology would have to be maintained by active means. Energy has to be spent to maintain the negative host roughness topology to minute detail, and protracted hitch-riding on sharks for feeding may not be free for echeneid fish. Further work is needed on the mechanism and efficiency of the densely populated tiny actuators in the fish suckers that maintain leak-proof contact with minimal

  16. Relationship between proximal femoral and acetabular alignment in normal hip joints using 3-dimensional computed tomography.

    PubMed

    Buller, Leonard T; Rosneck, James; Monaco, Feno M; Butler, Robert; Smith, Travis; Barsoum, Wael K

    2012-02-01

    The bony architecture of the hip depends upon functional adaptation to mechanical usage via the dynamic interaction between the acetabulum and femoral head. Acetabular retroversion is thought to be a contributing factor of pincer-type femoroacetabular impingement. Studies of pathological hip joints suggest proximal femoral anatomy compensates for acetabular retroversion. HYPOTHESIS/ PURPOSE: The purpose of this study was to determine if a predictable relationship exists between proximal femoral and acetabular angles, age, and gender in normal hip joints. We hypothesized that, through functional adaptation to mechanical loading, a complementary developmental relationship exists between the acetabulum and proximal femur. Descriptive laboratory study. The femoral neck version, femoral neck shaft angle, acetabular version, acetabular inclination, and center edge angle were measured in 230 normal hip joints in 115 adults using 3-dimensional reconstruction software. Correlations between the angles, age, and gender were examined using the methods of stepwise regression and backward elimination. Regarding side-to-side comparison and variability, there was no statistically significant difference between the left and right sides in the average value of each angle measurement. The correlations specifically between angles, age, and gender were similar on the left and right sides for all pairs except femoral version and acetabular inclination. Regarding significant findings of the study, a positive correlation (P < .05) was found between femoral version and acetabular version (0.38° to 1°). A positive correlation was found between femoral neck shaft angle and acetabular version (0.21° to 1°). A negative correlation was found between femoral neck shaft angle and age (-0.17° to 1°). A positive correlation was found between acetabular version and female gender (2.6° to 1°). A positive correlation was found between center edge angle and female gender (2.8° to 1°). A

  17. Steady-state elastohydrodynamic lubrication analysis of a metal-on-metal hip implant employing a metallic cup with an ultra-high molecular weight polyethylene backing.

    PubMed

    Liu, F; Wang, F C; Jin, Z M; Hirt, F; Rieker, C; Grigoris, P

    2004-01-01

    The elastohydrodynamic lubrication (EHL) analysis was carried out in this study for a 28 mm diameter metal-on-metal hip prosthesis employing a metallic cup with an ultra-high molecular weight polyethylene (UHMWPE) backing under a simple steady state rotation representing the flexion/extension during walking. Both Reynolds and elasticity equations were coupled and solved numerically by the finite difference method. The elastic deformation was determined by means of the fast Fourier transform (FFT) technique using the displacement coefficients obtained from the finite element method. Excellent agreement of the predicted elastic deformation was obtained between the FFT technique and the conventional direct summation method. The number of grid points used in the lubrication analysis was found to be important in predicting accurate film thicknesses, particularly at low viscosities representative of physiological lubricants. The effect of the clearance between the femoral head and the acetabular cup on the predicted lubricant film thickness was shown to be significant, while the effect of load was found to be negligible. Overall, the UHMWPE backing was found not only to reduce the contact pressure as identified in a previous study by the authors (Liu et al., 2003) but also significantly to increase the lubricant film thickness for the 28 mm diameter metal-on-metal hip implant, as compared with a metallic mono-block cup.

  18. Wear and migration of highly cross-linked and conventional cemented polyethylene cups with cobalt chrome or Oxinium femoral heads: a randomized radiostereometric study of 150 patients.

    PubMed

    Kadar, Thomas; Hallan, Geir; Aamodt, Arild; Indrekvam, Kari; Badawy, Mona; Skredderstuen, Arne; Havelin, Leif Ivar; Stokke, Terje; Haugan, Kristin; Espehaug, Birgitte; Furnes, Ove

    2011-08-01

    This randomized study was performed to compare wear and migration of five different cemented total hip joint articulations in 150 patients. The patients received either a Charnley femoral stem with a 22.2 mm head or a Spectron EF femoral stem with a 28 mm head. The Charnley articulated with a γ-sterilized Charnley Ogee acetabular cup. The Spectron EF was used with either EtO-sterilized non-cross-linked polyethylene (Reflection All-Poly) or highly cross-linked (Reflection All-Poly XLPE) cups, combined with either cobalt chrome (CoCr) or Oxinium femoral heads. The patients were followed with repeated RSA measurements for 2 years. After 2 years, the EtO-sterilized non-cross-linked Reflection All-Poly cups had more than four times higher proximal penetration than its highly cross-linked counterpart. Use of Oxinium femoral heads did not affect penetration at 2 years compared to heads made of CoCr. Further follow-up is needed to evaluate the benefits, if any, of Oxinium femoral heads in the clinical setting. The Charnley Ogee was not outperformed by the more recently introduced implants in our study. We conclude that this prostheses still represents a standard against which new implants can be measured. Copyright © 2011 Orthopaedic Research Society.

  19. No Benefit After THA Performed With Computer-assisted Cup Placement: 10-year Results of a Randomized Controlled Study.

    PubMed

    Parratte, Sebastien; Ollivier, Matthieu; Lunebourg, Alexandre; Flecher, Xavier; Argenson, Jean-Noel A

    2016-10-01

    Computer-assisted surgery (CAS) for cup placement has been developed to improve the functional results and to reduce the dislocation rate and wear after total hip arthroplasty (THA). Previously published studies demonstrated radiographic benefits of CAS in terms of implant position, but whether these improvements result in clinically important differences that patients might perceive remains largely unknown. We hypothesized that THA performed with CAS would improve 10-year patient-reported outcomes measured by validated scoring tools, reduce acetabular polyethylene wear as measured using a validated radiological method, and increase survivorship. Sixty patients operated on for a THA between April 2004 and April 2005 were randomized into two groups using either the CAS technique or a conventional technique for cup placement. All patient candidates for a THA with the diagnosis of primary arthritis or avascular necrosis were eligible for the CAS procedure and randomly assigned to the CAS group by the Hospital Informatics Department with use of a systematic sampling method. The patients assigned to the freehand cup placement group were matched for sex, age within 5 years, pathological condition, operatively treated side, and body mass index within 3 points. All patients were operated on through an anterolateral approach (patient in the supine position) using cementless implants. In the CAS group, a specific surgical procedure using an imageless cup positioning computer-based navigation system was performed. There were 16 men and 14 women in each group; mean age was 62 years (range, 24-80 years), and mean body mass index was 25 ± 3 kg/m(2). No patient was lost to followup at 10 years, but five patients have died (two in the CAS group and three in the control group). At the 10-year followup, an independent observer blinded to the type of technique performed patients' evaluation. Cup positioning was evaluated postoperatively using a CT scan in the two groups with results

  20. Migration and head penetration of Vitamin-E diffused cemented polyethylene cup compared to standard cemented cup in total hip arthroplasty: study protocol for a randomised, double-blind, controlled trial (E1 HIP)

    PubMed Central

    Sköldenberg, Olof; Rysinska, Agata; Chammout, Ghazi; Salemyr, Mats; Muren, Olle; Bodén, Henrik; Eisler, Thomas

    2016-01-01

    Introduction In vitro, Vitamin-E-diffused, highly cross-linked polyethylene (PE) has been shown to have superior wear resistance and improved mechanical properties when compared to those of standard highly cross-linked PE liners used in total hip arthroplasty (THA). The aim of the study is to evaluate the safety of a new cemented acetabular cup with Vitamin-E-doped PE regarding migration, head penetration and clinical results. Methods and analysis In this single-centre, double-blinded, randomised controlled trial, we will include 50 patients with primary hip osteoarthritis scheduled for THA and randomise them in a 1:1 ratio to a cemented cup with either argon gas-sterilised PE (control group) or Vitamin-E-diffused PE (vitamin-e group). All patients and the assessor of the primary outcome will be blinded and the same uncemented stem will be used for all participants. The primary end point will be proximal migration of the cup at 2 years after surgery measured with radiostereometry. Secondary end points include proximal migration at other follow-ups, total migration, femoral head penetration, clinical outcome scores and hip-related complications. Patients will be followed up at 3 months and at 1, 2, 5 and 10 years postoperatively. Results Results will be analysed using 95% CIs for the effect size. A regression model will also be used to adjust for stratification factors. Ethics and dissemination The ethical committee at Karolinska Institutet has approved the study. The first results from the study will be disseminated to the medical community via presentations and publications in relevant medical journals when the last patient included has been followed up for 2 years. Trial registration number NCT02254980. PMID:27388352

  1. Toward automated classification of acetabular shape in ultrasound for diagnosis of DDH: Contour alpha angle and the rounding index.

    PubMed

    Hareendranathan, Abhilash Rakkunedeth; Mabee, Myles; Punithakumar, Kumaradevan; Noga, Michelle; Jaremko, Jacob L

    2016-06-01

    The diagnosis of Developmental Dysplasia of the Hip (DDH) in infants is currently made primarily by ultrasound. However, two-dimensional ultrasound (2DUS) images capture only an incomplete portion of the acetabular shape, and the alpha and beta angles measured on 2DUS for the Graf classification technique show high inter-scan and inter-observer variability. This variability relates partly to the manual determination of the apex point separating the acetabular roof from the ilium during index measurement. This study proposes a new 2DUS image processing technique for semi-automated tracing of the bony surface followed by automatic calculation of two indices: a contour-based alpha angle (αA), and a new modality-independent quantitative rounding index (M). The new index M is independent of the apex point, and can be directly extended to 3D surface models. We tested the proposed indices on a dataset of 114 2DUS scans of infant hips aged between 4 and 183 days scanned using a 12MHz linear transducer. We calculated the manual alpha angle (αM), coverage, contour-based alpha angle and rounding index for each of the recordings and statistically evaluated these indices based on regression analysis, area under the receiver operating characteristic curve (AUC) and analysis of variance (ANOVA). Processing time for calculating αA and M was similar to manual alpha angle measurement, ∼30s per image. Reliability of the new indices was high, with inter-observer intraclass correlation coefficients (ICC) 0.90 for αA and 0.89 for M. For a diagnostic test classifying hips as normal or dysplastic, AUC was 93.0% for αA vs. 92.7% for αM, 91.6% for M alone, and up to 95.7% for combination of M with αM, αA or coverage. The rounding index provides complimentary information to conventional indices such as alpha angle and coverage. Calculation of the contour-based alpha angle and rounding index is rapid, shows potential to improve the reliability and accuracy of DDH diagnosis from 2DUS

  2. Immunohistochemical staining patterns of cytokeratins 13, 14, and 17 in oral epithelial dysplasia including orthokeratotic dysplasia.

    PubMed

    Nobusawa, Aiko; Sano, Takaaki; Negishi, Akihide; Yokoo, Satoshi; Oyama, Tetsunari

    2014-01-01

    Diagnosis of the exact grade of oral epithelial dysplasia is difficult, and interobserver variations in grading are common. The aim of this study was to investigate the expression patterns of cytokeratins (CKs) in dysplastic oral epithelia, to identify useful double immunostaining diagnostic markers. Immunoexpression of CK13, CK14, CK17, and Ki-67 were investigated in 21 normal epithelial specimens and 146 epithelial dysplasia specimens. In epithelial dysplasia specimens, orthokeratotic dysplasia (OKD) was identified using CK10 immunostaining. Most mild dysplasia specimens were CK13+ and CK17-. In moderate dysplasia, CK13 expression tended to be lower and CK17 expression tended to be higher than in mild dysplasia. All carcinoma in situ (CIS) specimens were CK17+. In differentiated type CIS specimens, CK13 expression was weakly positive. Most epithelial dysplasia specimens were CK14+. There were no significant differences in the expression patterns of CKs between OKD and non-OKD specimens in any of the grades of dysplasia. These results indicate that CK14 expression can be used to detect early epithelial dysplasia, and that CK13 and CK17 expression are useful for detecting neoplastic changes. © 2014 The Authors. Pathology International © 2014 Japanese Society of Pathology and Wiley Publishing Asia Pty Ltd.

  3. Progressive Pseudorheumatoid Dysplasia or JIA?

    PubMed Central

    2017-01-01

    Progressive pseudorheumatoid dysplasia (PPD) or spondyloepiphyseal dysplasia tarda with progressive arthropathy (SEDT-PA) is a rare arthropathy of childhood involving the axial skeleton as well as small peripheral joints. A 10-year-old boy was referred by a general practitioner with pain and deformity in the fingers of hands and limping gait. There was no joint synovitis although the finger joints were bulky on examination with mild flexion deformity. Patient had exaggerated kyphosis and lumbar lordosis with pigeon chest and restricted hip joint movements. Anteroposterior X-rays of the hip joints revealed widened and flattened epiphyses of the femoral heads with narrow and irregular joint spaces. Hand X-rays revealed periarticular osteopenia, significant narrowing of the joint spaces of proximal interphalangeal, and distal interphalangeal joints, together with osseous enlargement of the basis of metacarpal bones and phalanges. Spinal X-rays revealed generalized platyspondyly and anterior beaking of vertebral bodies. There was a clear mega os trigonum in his feet images. All blood investigations were normal with no evidence of inflammation and thyroid hormone levels were normal. The diagnosis of PPD was favored by imaging studies and normal inflammatory markers and the patient was treated with physiotherapy, family counseling, and anti-inflammatory medications. PMID:28316857

  4. DYSPLASIA OF HIP DEVELOPMENT: UPDATE

    PubMed Central

    Guarniero, Roberto

    2015-01-01

    The term “developmental dysplasia of the hip” (DDH) includes a wide spectrum of abnormalities that affect the hip during its growth, ranging from dysplasia to joint dislocation and going through different degrees of coxofemoral subluxation. The incidence of DDH is variable, and depends on a number of factors, including geographical location. Approximately one in 1,000 newborn infants may present hip dislocation and around 10 in 1,000 present hip instability. Brazil has an incidence of five per 1,000 in terms of findings of a positive Ortolani sign, which is the early clinical sign for detecting the disorder. The risk factors for DDH include: female sex, white skin color, primiparity, young mother, breech presentation at birth, family history, oligohydramnios, newborns with greater weight and height, and deformities of the feet or spine. Hip examinations should be routine for newborns, and should be emphasized in maternity units. Among newborns and infants, the diagnosis of DDH is preeminently clinical and is made using the Ortolani and Barlow maneuvers. Conventional radiography is of limited value for confirming the diagnosis of DDH among newborns, and ultrasound of the hip is the ideal examination. The treatment of DDH is challenging, both for pediatric orthopedists and for general practitioners. The objectives of the treatment include diagnosis as early as possible, joint reduction and stabilization of the hip in a secure position. Classically, treatment options are divided according to different age groups, at the time of diagnosis. PMID:27022528

  5. Metatropic Dysplasia with a Novel Mutation in TRPV4.

    PubMed

    Narayanan, Dhanya Lakshmi; Bhavani, Gandham SriLakshmi; Girisha, Katta Mohan; Phadke, Shubha R

    2016-08-08

    Metatropic dysplasia is a skeletal dysplasia characterized by rhizomelia, severe kyphoscoliosis and a coccygeal tail. A 12 day-old male neonate had facial dysmorphism, short limbs and coccygeal tail and showed radiological features of metatropic dysplasia. A novel heterozygous variant was observed in TRPV4 gene. We report a novel mutation in an Indian neonate with metatropic dysplasia.

  6. Fibrous Dysplasia in the Epiphysis of the Distal Femur

    PubMed Central

    Noh, Jung Ho; Lee, Jae Woo

    2017-01-01

    Fibrous dysplasia is a common benign skeletal lesion that may involve a single bone or multiple bones. Although fibrous dysplasia can affect any bone, monostotic fibrous dysplasia of the long bone typically occurs in the diaphysis or metaphysis. We report a very rare case of monostotic fibrous dysplasia involving the epiphysis of the distal femur in a young man. PMID:28231652

  7. Double mobility cup total hip arthroplasty in patients at high risk for dislocation: a single-center analysis.

    PubMed

    Kaiser, Dominik; Kamath, Atul F; Zingg, Patrick; Dora, Claudio

    2015-12-01

    Double mobility cup systems (DMCS) have gained increasing acceptance, especially in patients at high risk for dislocation. The aim of this investigation was to analyze the frequency and indications of the DMCS use in our praxis and to evaluate dislocation and cup revision rates after a minimum follow-up of 2 years. All patients implanted with a DMCS from May 2008 to August 2011 were identified from our institutional database of primary and revision THA procedures. Patient demographics, including ASA score, were recorded, along with details of the surgical procedures, indications for DMCS use, and post-operative clinical course and any complications. Radiographs were analyzed for implant positioning and radiological signs of loosening. 1046 primary THA were implanted, of these 39 (4 %) primary DMCS. Indications were severe neuromuscular disease (SND) (14), hip abductor degeneration (HAD) (9), cognitive dysfunction (CD) (8) and others. 345 revision THA were performed, of these 50 (14 %) revision DMCS. Indications were recurrent dislocations (27), multiple prior hip surgeries (13), HAD (5), CD (3) and others. Overall dislocation rate was 2/89 (2 %); both in revision THA. Overall cup revision rate was 5/89 (6 %): 3 septic, 1 periprosthetic acetabular fracture, 1 "intraprosthetic dissociation". 67 patients were available for the standardized questionnaire at a median follow-up of 43 months (range 25-78). 19 patients were not available for two-year follow-up: 17 died and two were lost to follow-up. This study supports the use of DMCS constructs in primary and revision hip arthroplasty for specific high-risk patients. We continue to indicate DMCS in this patient group. We do caution against extending indications for DMCS to lower risk patient groups due to unknown issues surrounding wear and component longevity.

  8. Effectiveness of four sterilizing procedures on prophylaxis cups.

    PubMed

    Forgas, L B; Durland, B J; Duncanson, M G; Parker, D E

    1990-12-01

    Though manufactured as a single use, disposable item, prophylaxis (prophy) cups are often cleaned, sterilized or disinfected, and re-used. The purpose of this study was to determine whether 1) sterilization of prophy cups is achieved during routine procedures 2) debris is completely removed after cleaning. Three types of prophy cups (250 of each type) were evaluated. Prophy cups were contaminated with a pumice slurry containing B. stearothermophilus spore. After contamination, cups were distributed equally between ultrasonic or manual cleaning, then further distributed to one of four sterilization procedures: ETO, chemiclave, autoclave, and glutaraldehyde (GLU) immersion (6 3/4 hours). Five cups served as control and were not subjected to sterilization. Additionally, 15 prophy cups were contaminated and immersed in GLU for 10 minutes. Results indicate sterilization may be achieved by all sterilization methods tested. However, recommended disinfection immersion time of 10 minutes for GLU was not effective in achieving adequate disinfection of prophy cups. Photomicrographs indicate debris remains trapped in prophy cups after manual or ultrasonic cleaning. Prophy cup sterilization may be achieved through standard routine sterilization procedures, but remaining debris is likely due to porosity of rubber and configuration of the cups. Time management, cost effectiveness, and sound clinical judgment suggest single use.

  9. Reusable and disposable cups: An energy-based evaluation

    NASA Astrophysics Data System (ADS)

    Hocking, Martin B.

    1994-11-01

    A group of five different types of reusable and disposable hot drink cups have been analyzed in detail with respect to their overall energy costs during fabrication and use. Electricity generating methods and efficiencies have been found to be key factors in the primary energy consumption for the washing of reusable cups and a less important factor in cup fabrication. In Canada or the United States, over 500 or more use cycles, reusable cups are found to have about the same or slightly more energy consumption, use for use, as moulded polystyrene foam cups used once and then discarded. For the same area paper cups used once and discarded are found to consume less fossil fuel energy per use than any of the other cup types examined. Details of this analysis, which could facilitate the comparative assessment of other scenarios, are presented.

  10. [Imaging evaluations of Salter innominate osteotomy for developmental dysplasia of the hip].

    PubMed

    Sun, Yongjian; Zhao, Li; Yu, Bin; Hu, Yanjun; Hu, Yifen; Chang, Siling

    2014-04-15

    To evaluate the imaging efficacies after Salter innominate osteotomy for developmental dysplasia of the hip (DDH). A total of 51 DDH patients with 70 hips were recruited between March 2011 to August 2012. All of them underwent Salter innominate osteotomy. Preoperative radiographs including acetabular index (AI), sharp angle (SA), obturator angle and obturator height were measured. And postoperative radiographs were taken at 2 days, 3 months, 6 months and 1 year to measure the parameters of AI, sharp acetabular angle, obturator angle, obturator height, shifting index and descending angle of distal iliac end. Paired t test was used for statistical analyses. The average correction of AI was 35.5° ± 2.3° preoperatively versus 14.6° ± 1.6° postoperatively ( P = 0.000) . The average correction of Sharp angle was 50.6° ± 3.7° preoperatively versus 33.1° ± 3.2° postoperatively (P = 0.000) . The average correction of obturator angle was 58.3° ± 3.9° preoperatively versus 39.5° ± 2.8° postoperatively (P = 0.000) . The average correction of obturator height was (1.65 ± 0.26) cm preoperatively versus (1.10 ± 0.14) cm postoperatively (P = 0.000) . At 3 months, 6 months and 1 year post-operation, the average values of AI, SA, obturator angle and obturator height continued to fall. Both of them showed statistical improvement. Shifting index and descending angle of distal iliac end were 30.1% ± 3.6% and 31.3° ± 4.1° on average. Six (8.57%) Shenton lines were bad. The imaging evaluations of acetabulum and pelvis show marked improvements until 1 year in DDH patients after Salter innominate osteotomy. It provides data reference for operative evaluations through measuring the imaging parameters of truncation bone.

  11. Hypotrichosis and nail dysplasia: a novel hidrotic ectodermal dysplasia.

    PubMed

    Harrison, Shannon; Sinclair, Rodney

    2004-05-01

    We report a unique isolated hair and nail ectodermal dysplasia in a 3-year-old girl. Clinical examination revealed short, sparse scalp hair, absent eyebrows, short eyelashes and nail dystrophy in all digits. Nail changes included shortened nail plate with distal onycholysis and loss of the cuticle. Sweating and teeth were normal. Development was normal. Scanning electron microscopy of the hair only demonstrated trichorrhexis nodosa. There was no pili torti. Vertically sectioned scalp biopsy revealed hypoplastic hair follicles and a horizontally sectioned biopsy showed a decrease in the overall number of hair follicles present. Treatment with topical minoxidil 5% 1 mL twice each day massaged into the scalp led to only minimal improvement and was discontinued after 12 months.

  12. Long Term Results of Liner Polyethylene Cementation Technique in Revision for Peri-acetabular Osteolysis.

    PubMed

    Rivkin, Gurion; Kandel, Leonid; Qutteineh, Bilal; Liebergall, Meir; Mattan, Yoav

    2015-06-01

    Patients with peri-acetabular osteolysis around a well fixed cementless acetabular component may be treated with liner exchange. When the locking mechanism is unreliable or unavailable, cementing the liner into the fixed acetabular component is a feasible option. The purpose of this study was to evaluate the clinical and radiographic long term results of this technique. Forty hip revisions with liner cementation in 37 patients were performed. The minimum follow up was 10 years. Modified Harris Hip Score and recent x rays were reviewed. Four hips were re-revised. Two patients were diagnosed with exacerbation of osteolysis but refused revision. Dislocation rate was relatively high (16%). Liner cementation technique in revision hip surgery is useful in patients with a well fixed metal backed acetabular component.

  13. [Long-term clinical and radiological outcomes in a serie of 26 cases of symptomatic adult developmental dysplasia of the hip managed with bernese periacetabular osteotomy].

    PubMed

    Alcobía Díaz, B; Luque Pérez, R; García Bullón, I; Moro Rodríguez, L E; López-Durán Stern, L

    2015-01-01

    Developmental hip dysplasia is a frequent cause of coxofemoral pain in young adults. Bernese periacetabular osteotomy emerges as a possible option for the management of pain relief and functional limitation, in order to delay the need for arthroplasty in these patients. A descriptive-retrospective study was conducted on 26 selected patients with symptomatic developmental hip dysplasia treated with bernese periacetabular osteotomy between 1996 and 2009 (94% women). Mean age at time of surgery was 39.8 y (15-49 y), with a mean follow-up of 10 years. Osteoarthritis (OA Tönnis scale), acetabular index and Wiberg angle were evaluated by radiology and functionality was valued by using the de Merle-D'Aubigné-Postel scale. The mean hospitalization time was 10 days. At 10 years, the mean radiography value of acetabular index was 9.03° and 38.3° for Wiberg angle (17° and 27° correction, respectively, above the mean pre-operative values). Joint lock was referred to by 43% of patients, and 53% to non-evidence based limb failure. Mean functional value was 14.30 (Good). At 5 years of follow-up, 20% advanced at least by one grade in OA Tönnis scale compared to their pre-operative status, increasing to 55% at 10 years. At 10 years after surgery, 83% patients did not need arthroplasty and 85% showed high satisfaction level. Bernese periacetabular osteotomy is a useful alternative in young adults with symptomatic developmental hip dysplasia that can improve pain relief, femoral head coverage, and slow down coxofemoral osteoarthrosis progression in order to delay arthroplasty. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.

  14. Epithelial Dysplasia and Cancer in IBD Strictures.

    PubMed

    Sonnenberg, Amnon; Genta, Robert M

    2015-09-01

    Colonic strictures and epithelial dysplasia are both known risk factors for the occurrence of colorectal cancer in inflammatory bowel disease (IBD) patients. The aim of the present work was to study colonic stricture as a risk factor for the occurrence of epithelial dysplasia and colonic adenocarcinoma. In a case-control study among 53568 IBD patients undergoing colonoscopy, we compared the prevalence of strictures among cases with dysplasia or adenocarcinoma and controls without such complications by calculating odds ratios (ORs) and their 95% confidence intervals (CIs). Multivariate logistic regressions were used to assess the joint influence of multiple predictor variables (age, sex, IBD type and stricture) on the occurrence of colonic dysplasia or adenocarcinoma. The prevalence of strictures was 1.06% in ulcerative colitis (UC) and 8.71% in Crohn's disease (CD, OR 11.09, 95% CI 9.72-12.70). The prevalence of dysplasia was 3.22% in UC and 2.08% in CD (OR 0.75, 95% CI 0.65-0.86). The prevalence of dysplasia was similar in IBD patients with and without stricture: 2.82 and 2.41%, respectively. The prevalence of cancer was higher in IBD patients with than without stricture: 0.78 and 0.11%, respectively (OR 6.87, 95% CI 3.30-12.89). In the multivariate analysis, old age, male sex and UC, but not stricture, were all significantly and independently associated with dysplasia. Old age, dysplasia and stricture were significantly and independently associated with cancer. The prevalence of epithelial dysplasia is not generally increased in IBD patients with strictures. Published by Oxford University Press on behalf of European Crohn’s and Colitis Organisation (ECCO) 2015. This work is written by US Government employee and is in the public domain in the US.

  15. Risk factors associated with Barrett's epithelial dysplasia.

    PubMed

    Fujita, Mikiko; Nakamura, Yuri; Kasashima, Saeko; Furukawa, Maiko; Misaka, Ryoichi; Nagahara, Hikaru

    2014-04-21

    To elucidate risk factors associated with dysplasia of short-segment Barrett's esophagus (BE). A total of 151 BE patients who underwent endoscopic examination from 2004 to 2008 in Aoyama Hospital, Tokyo Women's Medical University, Japan and whose diagnosis was confirmed from biopsy specimens were enrolled in the study. BE was diagnosed based on endoscopic findings of gastric-appearing mucosa or apparent columnar-lined esophagus proximal to the esophagogastric junction. Dysplasia was classified into three grades - mild, moderate and severe - according to the guidelines of the Vienna Classification System for gastrointestinal epithelial neoplasia. Anthropometric and biochemical data were analyzed to identify risk factors for BE dysplasia. The prevalence of Helicobacter pylori (H. pylori) infection and the expression of p53 by immunohistological staining were also investigated. Histological examination classified patients into three types: specialized columnar epithelium (SCE) (n = 65); junctional (n = 38); and gastric fundic (n = 48). The incidence of dysplasia or adenocarcinoma from BE of the SCE type was significantly higher than that of the other two types (P < 0.01). The univariate analysis revealed that sex, H. pylori infection, body weight, p53 overexpression, and low diastolic blood pressure (BP) were associated with BE dysplasia. In contrast, body mass index, waist circumference, metabolic syndrome complications, and variables related to glucose or lipid metabolism were not associated with dysplasia. Multivariate logistic analysis showed that overexpression of p53 [odds ratio (OR) = 13.1, P = 0.004], H. pylori infection (OR = 0.19, P = 0.066), and diastolic BP (OR = 0.87, P = 0.021) were independent risk factors for epithelial dysplasia in BE patients with the SCE type. Overexpression of p53 is a risk factor for dysplasia of BE, however, H. pylori infection and diastolic BP inversely associated with BE dysplasia might be protective.

  16. The "pirate sign" in fibrous dysplasia.

    PubMed

    Singnurkar, Amit; Rush, Chris

    2006-11-01

    Fibrous dysplasia commonly involves the skull in both its monostotic and polyostotic variants. We present two cases of fibrous dysplasia involving the sphenoid wing, which were strikingly similar in their bone scan appearance. Both patients demonstrated intense increased uptake of Tc-99m MDP in a pattern reminding us of a "pirate wearing an eyepatch." We propose that this characteristic appearance of fibrous dysplasia of the sphenoid wing be called the "pirate sign." A review of the literature revealed several other pathologic conditions that have been reported to involve the sphenoid bone and should be considered in the differential diagnosis of abnormal bone tracer uptake in this region.

  17. Fix and replace: An emerging paradigm for treating acetabular fractures in older patients

    PubMed Central

    Tissingh, Elizabeth K; Johnson, Abigail; Queally, Joseph M; Carrothers, Andrew D

    2017-01-01

    Acetabular fractures in older patients are challenging to manage. The “fix and replace” construct may present a new paradigm for the management of these injuries. We present the current challenge of acetabular fractures in older patients. We present this in the context of the current literature. This invited editorial presents early results from our centre and the ongoing challenges are discussed. PMID:28361014

  18. Retained Sponge: A Rare Complication in Acetabular Osteosinthesis

    PubMed Central

    Chana-Rodríguez, Francisco; Mañanes, Rubén Pérez; Rojo-Manaute, José; Moran-Blanco, Luz María; Vaquero-Martín, Javier

    2015-01-01

    Retained sponges after a surgical treatment of polytrauma may cause a broad spectrum of clinical symptoms and present a difficult diagnostic problem. We report a case of retained surgical sponge in a 35-year-old man transferred from another hospital, that sustained a open acetabular fracture. The fracture was reduced through a limited ilio-inguinal approach. After 4 days, he presented massive wound dehiscence of the surgical approach. An abdominal CT scan showed, lying adjacent to the outer aspect of the left iliac crest, a mass of 10 cm, identified as probable foreign body. The possibility of this rare complication should be in the differential diagnosis of any postoperative patient who presents with pain, infection, or palpable mass. PMID:26312116

  19. Do Radiographic Parameters of Dysplasia Improve to Normal Ranges After Bernese Periacetabular Osteotomy?

    PubMed

    Novais, Eduardo N; Duncan, Stephen; Nepple, Jeffrey; Pashos, Gail; Schoenecker, Perry L; Clohisy, John C

    2017-04-01

    The goal of periacetabular osteotomy (PAO) is to improve the insufficient coverage of the femoral head and achieve joint stability without creating secondary femoroacetabular impingement. However, the complex tridimensional morphology of the dysplastic acetabulum presents a challenge to restoration of normal radiographic parameters. Accurate acetabular correction is important to achieve long-term function and pain improvement. There are limited data about the proportion of patients who have normal radiographic parameters restored after PAO and the factors associated with under- and overcorrection. (1) What is the proportion of patients undergoing PAO in which the acetabular correction as assessed by the lateral center-edge angle (LCEA), anterior center-edge angle (ACEA), acetabular inclination (AI), and extrusion index (EI) is within defined target ranges? (2) What patient and preoperative factors are associated with undercorrection of the acetabulum as defined by a LCEA < 22°, a factor that has been reported to be associated with PAO failure at 10-year followup? Between January 2007 and December 2011 we performed 132 PAOs in 116 patients for treatment of symptomatic acetabular dysplasia. One patient with Legg-Calvé-Perthes disease, one with multiple osteochondromatosis, and two with concomitant femoral osteotomy were excluded. A total of 128 hips (112 patients) were included. The hip cohort was 76% (97 of 128) female and the mean age at surgery was 28.5 years (SD 8.7 years). Correction of LCEA between 25° and 40°, ACEA between 18° and 38°, Tönnis angle between 0° and 10°, and EI ≤ 20% were defined as adequate based on normative values. Values lower than the established parameters were considered undercorrection for the LCEA and ACEA and those higher than the established values were considered overcorrection. Because postoperative LCEA < 22(o) has been previously associated with PAO failure at a minimum of 10-year followup, in this study we sought to

  20. Double pelvic osteotomy for the treatment of hip dysplasia in young dogs.

    PubMed

    Vezzoni, A; Boiocchi, S; Vezzoni, L; Vanelli, A B; Bronzo, V

    2010-01-01

    The aim of this study was to evaluate the feasibility of the double pelvic osteotomy (DPO) (osteotomy of the ilium and pubis) to treat clinical cases of hip dyplasia in young dogs instead of performing a triple pelvic osteotomy (TPO) (osteotomy of the ilium, pubis, and ischium). Candidates for DPO were 4.5- to nine-month-old dogs with coxofemoral joint subluxation and laxity, indicative of susceptibility to future development of severe hip dysplasia. The angle of reduction (AR) and angle of subluxation (AS) with Ortolani's sign, Norberg angle (NA), percentage of femoral head (PC) covered by the acetabulum, and the pelvic diameters and their relationships were measured clinically and radiographically before and after surgery. The surgical technique was similar to the TPO technique, but excluded ischiatic osteotomy. A DPO was carried out in 53 joints of 34 dogs; AR and AS values immediately postoperatively and at the one- and two-month follow-up examinations were significantly lower than the preoperative values (p <0.01). The complications encountered were mainly represented by implant failure (3.5%), partial plate pull-out (9.4%), and incomplete fracture of the ischial table (7.5%). Changes in PC and NA values obtained immediately after surgery and at the first and second follow-up examinations were significantly greater (p <0.01 both) than values obtained before surgery. Sufficient acetabular ventroversion was achieved to counteract joint subluxation and the modifications of AR and AS. The NA and PC direct postoperative values reflected a significant improvement in the dorsal acetabular coverage. Restoration of normal joint congruity (PC from 50 to 72%) and maintenance of the pelvic geometry without pelvic narrowing were the most intriguing features of DPO. The complications observed were greatly reduced when using dedicated DPO plates. Based on our experience, the morbidity after unilateral and bilateral DPO was lower than after TPO because elimination of the

  1. Solar Probe Cup - Demonstrated Laboratory Performance

    NASA Astrophysics Data System (ADS)

    Case, A. W.; Kasper, J. C.; Korreck, K. E.; Stevens, M. L.; Larson, D. E.; Wright, K. H., Jr.; Gallagher, D. L.; Whittlesey, P. L.

    2016-12-01

    The Solar Probe Cup (SPC) is a Faraday Cup instrument that will fly on the Solar Probe Plus (SPP) spacecraft, orbiting the Sun as close as 9.86 solar radii from the center of the Sun. The SPC instrument is designed to measure the thermal solar wind plasma (protons, alphas, and electrons) that will be encountered throughout its close encounter with the Sun. Due to the solar wind flow being primarily radial, the SPC instrument is pointed directly at the Sun, resulting in an extreme thermal environment that must be tolerated throughout the primary data collection phase. Laboratory testing has been performed over the past 6 months to demonstrate the instrument's performance relative to its requirements, and to characterize the measurements over the expected thermal range. This presentation will demonstrate the performance of the instrument as measured in the lab, describe the operational configurations planned for flight, and discuss the data products that will be created.

  2. Sampling Bias on Cup Anemometer Mean Winds

    NASA Astrophysics Data System (ADS)

    Kristensen, L.; Hansen, O. F.; Højstrup, J.

    2003-10-01

    The cup anemometer signal can be sampled in several ways to obtain the mean wind speed. Here we discuss the sampling of series of mean wind speeds from consecutive rotor rotations, followed by unweighted and weighted averaging. It is shown that the unweighted averaging creates a positive bias on the long-term mean wind speed, which is at least one order of magnitude larger than the positive bias from the weighted averaging, also known as the sample-and-hold method. For a homogeneous, neutrally stratified flow the first biases are 1%-2%. For comparison the biases due to fluctuations of the three wind velocity components and due to calibration non-linearity are determined under the same conditions. The largest of these is the v-bias from direction fluctuations. The calculations pertain to the Risø P2546A model cup anemometer.

  3. Analysis of Earing in Deep Drawn Cups

    SciTech Connect

    Aretz, Holger; Aegerter, Johannes; Engler, Olaf

    2010-06-15

    The cup-drawing of a strongly anisotropic sheet metal is simulated using a commercial finite element software along with a user material subroutine. In order to accurately describe the plastic anisotropy of the material the well-known recent yield function 'Yld2004-18p' is extended. Regarding the experimental characterization of the considered material the occurrence of dynamic strain aging lead to an oscillating signal of the width change of the tensile samples, which prevented a reliable determination of plastic strain ratios (r-values). Thus, an improved measurement concept was developed that leads to a very robust and reproducible determination of r-values. Furthermore, a novel plane-strain tensile test sample is presented which is used for the characterization of the plastic anisotropy in biaxial loading states. A quantitative comparison with measured earing profiles of deep drawn cups illustrates the predictive capabilities of the numerical simulation.

  4. CUP-syndrome diagnostic procedure scheme.

    PubMed

    Pujanek, Zuzanna; Burduk, Paweł K

    2013-01-01

    Patients with CUP-Syndrome represent a small percentage of patients treated by ENT doctor. Often, in spite of the implementation detailed diagnostics, detection of the primary tumor fails. Very important element is to follow the correct sequence of tests and taking into account conditions outside ENT. I our article, we would like to propose a diagnostic scheme including interview with patient, laryngological and imaging tests and multi-disciplinary consulting. We hope that this scheme will facilitate the treatment of patients with CUP-Syndrome and increase the efficiency of detection of primary tumor. Copyright © 2013 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

  5. Acetabular cartilage defects cause altered hip and knee joint coordination variability during gait

    PubMed Central

    Samaan, Michael A.; Teng, Hsiang-Ling; Kumar, Deepak; Lee, Sonia; Link, Thomas; Majumdar, Sharmila; Souza, Richard B.

    2015-01-01

    Background Patients with acetabular cartilage defects reported increased pain and disability compared to those without acetabular cartilage defects. The specific effects of acetabular cartilage defects on lower extremity coordination patterns are unclear. The purpose of this study was to determine hip and knee joint coordination variability during gait in those with and without acetabular cartilage defects. Methods A combined approach, consisting of a semi-quantitative MRI-based quantification method and vector coding, was used to assess hip and knee joint coordination variability during gait in those with and without acetabular cartilage les