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At least 1,081 records · Page 60Linked to original sources
PubMed2000

Six new species of Lepidapedon Stafford, 1904 (Digenea: Lepocreadiidae) from deep-sea macrourid fishes from the Gulf of Mexico and Caribbean Sea, with revised keys to the species of the genus.

Species of the genus Lepidapecon are divided into various groups and subgroups based on vitelline distribution relative to the acetabulum and anterior extent of the excretory vesicle. Members of this genus predominantly parasitise gadiform fishes and are commonly collected from relatively deep waters. A recent study of deep-sea helminths from macrourids of the Gulf of Mexico and Caribbean Sea revealed six new species of this genus. L. mexicanensis n. sp., of the elongatum group, elongatum subgroup, differs from other species in this subgroup in proportions (as % of body length), lacking confluent vitelline fields between both the ovary and anterior testis and the testes, and in having a smaller egg and body size. L. nezumiatis n. sp., of the elongatum group, desclersae oesophagus than prepharynx. L. caribbaei n. sp. and L. longivesicula n. sp., of the garrardi group, congeri sub-subgroup, differs from both L. filiformis and L. desclersae in having intermediate egg and body sizes, and a longer group, differ from L. congeri in having a sucker-ratio of 1: < 1. L. caribbaei n. sp. and L. longivesicula n. sp. differ from each other in that L. caribbaei n. sp. has numerous long, barb-like, deeply imbedded spines, a less elongate body, an infundibuliform oral sucker, a similar-sized oesophagus and prepharynx, and a caecal bifurcation which is closer to the acetabulum than oral sucker, while L. longivesicula n. sp. has shorter, serrate or plate-like, lightly imbedded, widely to sporadically spaced spines, a more elongate body, a spherical to subspherical oral sucker, a longer oesophagus than prepharynx, and a caecal bifurcation which is closer to the oral sucker than acetabulum. L. desotoensis n. sp., of the rachion group, rachion subgroup, is distinct from both L. luteum and L. abyssensis in having a smaller size, lacking cervical glands or pharyngeal gland cells, and possessing dark-staining particles in the mesenchyme, while it differs from L. abyssensis specifically in having a much longer oesophagus than prepharynx, lateral vitelline fields that are not confluent intertesticularly, and wider eggs. L. zaniophori n. sp., also of the rachion subgroup, differs from both L. cascadensis and L. genge in having a smaller egg size, a shorter prepharynx and oesophagus than pharynx, and vitelline fields that are intertesticular but only slightly encroach between the ovary and anterior testis. L. sammari and L. spiniferi are designated as incertae sedis, and L. quiloni and L. stromateusi are designated as species inquirendae. New parasite keys and host records for Coelorinchus coelorhincus. C. caribbaeus and Nezumia cyrano are offered. Support is given to Lepidapedon probably being the dominant digenean genus in deep water.

Animals↗
PubMed2002

Don't throw away the ring: indications and use.

Protective rings are a valuable adjunct in revision acetabular surgery. Two types of rings are used. The roof ring, which is the smaller of the 2 rings, provides support from the ilium to the inferomedial part of the acetabulum. The reconstructive ring or cage provides support from the ilium to the ischium. Both devices can be used to protect morcellized or structural bone-graft. The roof ring can be used with morcellized graft if the ring can make contact with host-bone at the superior and inferomedial aspect of the acetabulum. If the defect is more global but still contained so that the entire acetabulum is filled with morcellized bone, the larger reconstructive ring should be used. Small structural grafts that support <50% of the cup may be protected by a roof ring. Larger structural grafts that support >50% of the cup should be protected by a reconstructive ring.

Arthroplasty, Replacement, Hip↗
PubMedDate not supplied

[Transverse skeletal axes of the lower extremity in coxarthrosis].

Femoral anteversion, anteversion of the acetabulum and tibial torsion of 47 patients with idiopathic osteoarthritis of the hip were determined by computerized tomography. From all these parameters only the anteversion of the acetabulum showed differing values in hips with and without osteoarthritis. There was a considerable range at the individual measured values in all parameters and differences between the male and female groups could be found in femoral anteversion and anteversion of the acetabulum.

Biomechanical Phenomena↗
PubMedDate not supplied

[Implant fractures in ceramic hip endoprostheses].

Between 1974 and 1987, a total of 2356 ceramic hip endoprostheses, both primary and secondary, were implanted at the Orthopedic University Clinic in Homburg/Saar. Strem fractures occurred in three of these patients only, which corresponds to a relative frequency of 0.13%. In two instances, these were fatigue fractures of the AUTOPHOR I (WISIL) prosthesis stem, while in the third instance the fracture, of stem type 2 (ENDOCAST), was the result of a fault during casting. Fractures of ceramic components as a result of a direct trauma of sufficient force were observed in six cases (relative frequency of 0.25%). Persistent fractures only occurred where there was recurrent knocking of a long ceramic collar against the rim of the acetabulum (eight cases, relative frequency of 0.34%), mainly as a result of primary or secondary false positioning of the acetabulum (surgical error, aseptic loosening). Ceramic fractures when using the ceramics/polyethylene combination for joints have yet to be recorded. Given the authors' 12 years of experience, and considering the large number of patients treated fractures of high quality BIOLOX ceramics are a rarity. Both persistent fractures and exaggerated ceramic abrasion were almost always the result of false positioning of the acetabulum, with the recurrent knocking of the hip head ceramic collar playing a significant role. It is evident that the extent of tolerance of ceramics as regards undue strain with a subsequent danger of fracture is lower than that of the metal-polyethylene combination.

Ceramics↗
PubMed1981

[Treatment of congenital dislocation of the hip in older children (author's transl)].

In children who are older than three years the obstacles of reduction can be overcome without danger for the blood supply of the femoral head only by operative measures. It stands the test to combine open reduction with the nearly always necessary correction of the dysplastic acetabulum, the shortening of the femur and derotating osteotomy. The results definitely depend on the individual indication and the operating technique. In cases of severe dysplasia of the acetabulum the acetabuloplasty shows better results in correction and reduction of the hip joint than Salter's osteotomy. Chiari's osteotomy of the pelvis should be taken into consideration only in such special cases with residual subluxation or with an extreme flat acetabulum. The follow up of 67 congenital dislocations of the hip in children aged between three and thirteen years shows, that operative treatment of bilateral luxation is indicated in patients between three and six years of age and unilateral luxation up to the age of adolescence.

Age Factors↗
PubMedDate not supplied

Diagnostic and operative arthroscopy of the coxofemoral joint in horses.

Arthroscopic examination of the hip joint was performed in mature and juvenile horses, using a lateral approach and standard or long instruments depending on body weight. Nine hip joints were examined in three cadavers and four anesthetized horses. The lateral, cranial, and caudal regions of the femoral head and acetabulum were accessible, and, after distraction of the limb, the ligament of the head of the femur and the acetabular notch were also visible. In small horses, the medial regions of the hip joint were visible but were inaccessible in larger horses. Iatrogenic injury to the sciatic nerve or periarticular vasculature was not evident at necropsy examination. Six horses with lameness localized to the hip joint were examined arthroscopically. At surgery, two horses had tearing of the ligament of the head of the femur, two horses had osteochondrosis of the femoral head or acetabulum, and two horses had degenerative joint disease, one associated with a rim fracture of the caudal aspect of the acetabulum and the other of indeterminant origin. Improvement after debridement occurred in one of the horses with partial disruption of the ligament of the head of the femur and in both horses with osteochondrosis. Diagnostic and surgical arthroscopy of the hip can be accomplished in foals and weanlings using standard equipment, but, in adults weighing more than 300 kg, longer instruments are required and the ease of access and the visible extent of the hip joint is considerably reduced.

Animals↗
PubMed2005

Description of Dendrorchis retrobiloba n. sp. (Digenea: Gorgoderidae) from Astyanax fasciatus (Teleostei: Characidae) from Southern Uruguay, with an emended diagnosis of the genus Dendrorchis.

To date, the monospecific Dendrorchis is represented by D. neivai, reported from Brazil and parasitizing Brycon lundi. Dendrorchis retrobiloba n. sp. is described from the swim bladder of Astyanax fasciatus from Cañada del Dragón stream in Montevideo, southern Uruguay (34 degrees 47'S, 56 degrees 14'W), and the emended diagnosis of Dendrorchis is given. The diagnosis of Dendrorchis has been modified to include the following characters: Phyllodistominae with flattened body, wider in the region posterior to acetabulum. Intestinal ceca sinuous or not. Testes branched or with superficial lobes. Ovary with deep or superficial lobes. Seminal receptacle present or absent. Vitellaria ellongate or pyriform. Uterus extends to posterior region and to portion of body anterior to acetabulum. Eggs oval, variable size, thin-shelled, without opercula. Dendrorchis retrobiloba n. sp. differs from D. neivai by having pyriform vitellaria, ovary larger than the testes and not deeply lobed, wider distribution of the uterus, smaller egg size, testes with superficial lobes, oral sucker wider than the acetabulum, shorter esophagus, 2 terminal lobes at the posterior end of the body, and much smaller body length. Despite being found in different hosts, both species of Dendrorchis parasitize the swim bladder of freshwater Characidae.

Animals↗
PubMed2006

A new species of haploporid (Digenea) from the South China Sea.

Megasolena dongzhaiensis n. sp. was collected from the intestine of Scatophagus argus (Linnaeus) (Perciformes: Scatophagidae) from the Dongzhai Bay (110 degrees 32'-37'E, 19 degrees 51'-20 degrees 1'N), Hainan Province, China. It resembles Megasolena acanthuri Machida and Uchida, 1991 in having larger body size, but it differs from the latter species in having an oral sucker that is larger, instead of smaller, than the acetabulum (sucker length ratio 1:0.456-0.494, and width ratio 1:0.61-0.65 in M. dongzhaiensis n. sp., as opposed to 1:1.3-1.7 in M. acanthuri). Moreover, the cuticle is spinose rather than aspinose; there is a band of circular muscle in the pharynx, and its eggs are smaller instead of larger (0.062-0.068 x 0.036-0.039 in M. dongzhaiensis n. sp., compared with 0.087-0.103 x 0.058-0.072 in M. acanthuri). Finally, the intestinal bifurcation is anterior, instead of dorsal, to the acetabulum. It resembles other species of Megasolena Linton, 1910 in having oral sucker larger than the acetabulum, and in having a circular muscle band in the oral sucker and pharynx, but it differs in having a larger body and smaller eggs. This is the first record of a Megasolena species from ray-finned fishes as well as in China.

Animals↗
PubMed1999

Concordance between hip ultrasonography and hip arthrography in the assessment of developmental dysplasia of the hip.

Controversy exists regarding the possibility of predicting hip reducibility in the congenitally dislocated hip, with arthrography still regarded as the gold standard in this situation. This study aims at assessing the degree of concordance between ultrasonography and arthrography in the detection of anatomic elements obstructing hip reduction. Forty-nine hips were studied both by ultrasonography and arthrography. Three anatomic sources of obstruction to reduction were assessed in each hip: ligamentum teres hypertrophy, inverted labrum, and the presence of soft tissue in the acetabulum. For each variable, congruence between ultrasound and arthrography was measured by kappa analysis. Values > 0.40 expressed sufficient concordance, and they were detected with regard to inverted labrum and the presence of soft tissue in the acetabulum. The results of this study suggest that ultrasonography may be considered a reliable technique for the prediction of the main causes of obstruction in the congenitally dislocated hip, such as inverted labrum and soft tissue in the acetabulum.

Arthrography↗
PubMed2002

Salter innominate osteotomy for the treatment of developmental dysplasia of the hip in children: results of seventy-three consecutive osteotomies after twenty-six to thirty-five years of follow-up.

BACKGROUND: Reorientation of the acetabulum may be necessary in the treatment of an unstable hip in children with developmental dysplasia of the hip. In 1961, Salter described the innominate osteotomy for stabilizing the reduced hip in the position of function by redirection of the acetabulum as one piece. In the present study, we describe our long-term results with this procedure. METHODS: We reviewed the cases of sixty-one patients who had seventy-three Salter innominate osteotomies. At the time of the operation, the mean age of the patients was 4.1 years (range, 1.3 to 8.8 years). Radiographs made preoperatively, postoperatively, and at the time of the most recent follow-up visit were evaluated. Clinical evaluation was performed with use of the Merle d'Aubigné and Postel system as well as the Harris hip score. RESULTS: The mean duration of follow-up was 30.9 years (range, 26.2 to 35.4 years). There were seven true revisions (one acetabuloplasty, one triple osteotomy, and five total hip arthroplasties). With true revision as the end point, the cumulative survival rate at 35.3 years was 0.90. Fifteen of the seventy-three hips were considered a failure, which was defined as a revision or a Harris hip score of <70 points and/or a Merle d'Aubigné and Postel score of <13 points. The long-term clinical outcome was significantly influenced by the grade of dislocation on the radiographs made at the first examination (p = 0.0388) and on those made immediately preoperatively (p < 0.0001), the postoperative summarized hip factor (the radiographic grade of dysplasia) (p = 0.0002), the preoperative (p = 0.0392) and postoperative (p = 0.0072) grades of avascular necrosis of the femoral head, and the technique of reduction (p < 0.0001). CONCLUSIONS: When an acetabulum can be most closely restored to a normal configuration without the development of avascular necrosis, good long-term results (lasting for more than thirty years) can be expected. When open reduction is necessary, it is preferable to perform it separately prior to the Salter innominate osteotomy. The grade of dislocation at the time of the first examination and immediately preoperatively, the grade of avascular necrosis of the femoral head, and the adequacy of surgical correction are important prognostic factors for the long-term clinical result.

Child↗
PubMed1975

[The coxopathies of Paget's disease. Radio-clinical and anatomopathological study].

A systematic study was carried out on 105 patients with Paget's disease (60 men and 45 women, average age 62 years) involving the acetabulum and/or the femoral head in the juxta-articular zone. In two-thirds of the patients only the pelvis (in particular the acetabulum) was affected, in a quarter both the pelvis and the femoral head were affected, and in one case in ten only the femoral head. 1. 18 coincidental coxopathies should first be excluded (12 coxarthrosis, 2 coxitis, etx.). The occurrence of 17 percent of coxopathies not caused by Paget's disease is normal in older patients (Vignon and Jacquet; Sebban, Lequesne et al.). 2. In 105 cases, there were only 50 coxopathies really due to Paget's disease, of which almost half remained painless. 3. This proportion did not vary with age. On the other hand, coxopathy was more frequent in patients with bipolar, pelvifemoral Paget's disease and above all in Paget's disease with acetabular protrusio. 4. The radiographic appearance is slightly different from that of coxarthrosis; the reduction in joint space is more often internal or supero-internal (50 percent of cases); osteophytosis is usually moderate (22 percent of cases), or absent (48 percent). The geodes are rarely visible : 6 percent of cases. 5. The acquired bone deformations in patients with Paget's disease are classical. In 105 cases, the authors noted 14 acetabular protrusions, all with coxopathies, and 10 coxa vara, 5 of which had coxapathies. Anatomo-pathological studies did not reveal anything in particular about the bone : superimposition of the Paget's disease lesions and of the lesions usually found in cases of coxopathy due to overload, with a dense pressure cone. With reference to cartilage, the lesions of Paget's coxopathies presented several specific characteristics compared with those of common arthrosis : (1) the presence of particularly numerous cupshaped defects on the remaining cartilage; (2) a very basophilic, intra- and extra-cytoplasmic substance impregnated the chondroplasts of the bottom layer, nine times out of twenty-six, an anomaly not observed in cases of arthrosis; (3) pseudo-angiomatous vascular outgrowths from the bone, flush with the articular surface of the acetabulum are a source of bleeding during surgery.

Adult↗
PubMed2004

[Acetabular reconstruction of total hip replacement in the treatment of dysplastic hip].

OBJECTIVE: To summarize the surgical experience of acetabular reconstruction of total hip replacement in the treatment of dysplastic hip. METHODS: From April 1998 to April 2002, 96 adult cases with osteoarthritis secondary to dysplastic hip were adopted in the study. Among them, there were 89 females and 7 males, age from 27 approximately 68 years. According to Hartofilakidis classification system, there were dysplasia in 73 hips, low dislocation in 18 hips and high dislocation in 21 hips. All patients received total hip replacement, 16 cases with bilateral replacement and 80 cases with unilateral replacement. Kocher-LangenBeck approach was used during operation and all the acetabular cups were reconstructed at the original anatomic location. The fixation methods were as follows: cement cup for 16 hips, cementless cup for 96 hips and bone graft in 11 hips. The reconstructive methods were as follows: regular replacement for 83 hips; installing a smaller cup after deeper reaming the acetabulum for 27 hips; installing a smaller cup after autofemoral grafting on the superior lip for 2 hips. RESULTS: The incision healed primarily and no infection or nerve injury occurred. Follow-up for 1 approximately 5 years (average for 3.5 years) in 85 patients, the Harris score increased from 33.9 preoperatively to 89.3 postoperatively, and 95 hips had good or excellent clinical results. Radiographically, the positions of the prostheses were normal, the average abduction angle of the cup was 44 degrees, the average superolateral bone coverage of the hips was 96.6%, no radiolucent line was observed at the acetabular side. All the bone grafts fused with the host bone successfully. CONCLUSIONS: Total hip replacement is an effective operation in the treatment of osteoarthritis secondary to dysplastic hip. The four specific factors that should be considered in acetabular reconstruction are: (1) the surgical approach, (2) the reconstructive position of the acetabulum, (3) the reconstructive method of the acetabulum, (4) the leg-length discrepancies. It's a challenging to the orthopaedic surgeon. Careful preoperative preparation is recommended.

Adult↗
PubMed2005

Severity of hip dysplasia and loosening of the socket in cemented total hip replacement. A long-term follow-up.

We have assessed the long-term results of 292 cemented total hip replacements which were performed for developmental dysplasia of the hip in 206 patients. The mean age of the patients at operation was 42.6 years (15.9 to 79.5) and most (202) were women. The severity of dysplasia was graded according to both the Crowe and the Hartofilakidis classifications. A 22.25-mm Charnley head was always used and the acetabular components were inserted with cement into the true acetabulum. Bone grafting of the acetabulum, using the patient's own femoral head, was performed on 48 occasions. At a mean follow-up of 15.7 years (2.2 to 31.2) the overall survival of the acetabular component was 78%. The main cause of revision was aseptic loosening (88.3%). The rate of survival at 20 years based on the Hartofilakidis classification was 76% in the dysplastic, 55% in the low-dislocation and 12% in the high-dislocation groups and on the Crowe classification, 72.7% for group I, 70.7% for group II, 36.7% for group III and 15.6% for group IV. There was no statistical correlation between bone grafting of the acetabulum and survival of the acetabular component. This study has shown a higher rate of failure of the acetabular component with increasing severity of hip dysplasia.

Adolescent↗
PubMed2006

Study of the morphology and biomechanics of sacral fracture.

OBJECTIVE: To observe the morphological characteristics of sacral fracture under different impact loads. METHOD: Ten fresh pelvic specimens were loaded in dynamic or static state. A series of mechanical parameters including the pressure strain and velocity were recorded. Morphological characteristics were observed under scanning electron microscope. RESULTS: The form of sacral fracture was related to the impact energy. Under low energy impact loads, ilium fracture, acetabulum fracture and crista iliaca fracture were found. Under high energy impact loads, three types of sacral fracture occurred according to the classification of Denis: sacral ala fracture, Type I fracture; sacral foramen cataclasm fracture, Type II fracture; central vertebral canal fracture, Type III fracture. Nerve injury of one or two sides was involved in all three types of sacral fracture. The fracture mechanism of sacrum between the dynamic impact and static compression was significantly different. When the impact energy was above 25 J, sacral foramen cataclasm fracture occurred, involving nerve root injury. When it was below 20 J, ilium and sacral fracture was most likely to occur. When it was 20 approximately 25 J, Type I fracture would occur. While in the static test, most of the fracture belonged to ilium or acetabulum fracture. The cross section of sacrum was crackly and the bone board of Haversian system was brittle, which could lead to separation of bone boards and malposition of a few of cross bone boards. CONCLUSIONS: In dynamic state, sacrum fracture mostly belongs to Type I and Type II, and usually involves the nerve roots. Sacrum fracture is relevant to the microstructures, the distribution of the bone trabecula, the osseous lacuna and the Haversian system of sacrum. The fracture of ilium and acetabulum more frequently appears in static state, with slight wound of peripheral tissues.

Biomechanical Phenomena↗
PubMed1989

[A roentogenographical study on the alignment of the lower extremities in secondary coxarthrosis].

Alignment of the lower extremities in secondary coxarthrosis (273 lower extremities) and controls (240 normal lower extremities) were studied using roentogenograms of whole lower extremities including the pelvis taken in the standing position with both legs. Secondary coxarthrosis, which is caused by congenital dislocation of the hip joint, was classified into four groups: unreduced dislocation, high dislocation, incomplete dislocation, and dysplasia of the acetabulum. Comparative studies were conducted using statistical data on measured items, obtained from secondary coxarthrosis cases and controls. In controls, the femoro-tibial angle (FTA) was 175.5 +/- 2.08 degrees and the mechanical axis passed through the medial side to the middle of the knee. It has been noted that a tendency for bow-legs was seen after the age of 50. In coxarthrosis with high dislocation, the most marked knock-knees were observed (FTA of 172.5 +/- 3.88 degrees), while in coxarthrosis with incomplete dislocation and dysplasia of the acetabulum, there was a tendency to coxa valga but no tendency toward knock-knees was evident. Cases of total hip replacement revealed that it is possible to improve knock-knees by installing a socket in the primary acetabulum as much as possible, correcting the difference between the length of the legs and elimating adduction contracture. It was also possible to study factors contributing to bow-legs and knock-knees by means of multivariate analysis.

Adolescent↗
PubMed1989

Rotational acetabular osteotomy for the severely dysplastic hip in the adolescent and adult.

Rotational acetabular osteotomy performed since 1968 is a circumacetabular osteotomy of the acetabulum for the dysplastic hip. The preoperative center-edge angle of Wiberg of 95 hips (89 patients) was -15 degrees or less. Forty-one hips (39 patients) form the basis of this report. They were followed from four years to 16 years and seven months (average, seven years and nine months). Twenty-one hips were classified as the Severin Group IV (subluxation) and 20 hips as the Severin Group V (a secondary acetabulum). A detailed assessment using a number of roentgenographic indices confirmed that the majority of the severely dysplastic hips could be corrected to nearly normal anatomy. The postoperative clinical results were assessed by the modified clinical classification of Severin proposed by Gibson and Benson. This procedure may be indicated for the severely dysplastic hip with subluxation or a secondary acetabulum in the adolescent and adult.

Adolescent↗
PubMed1989

Intraoperative autologous transfusion in orthopaedic patients.

The cases of 175 consecutive patients who had intraoperative autologous transfusion during revision total hip arthroplasty, an elective operation on the spine, repair of trauma to the spine, or open reduction of a fracture of the acetabulum were reviewed to evaluate the applicability of this technique in orthopaedic operations. A separate group of forty-one consecutive patients who had open reduction of a fracture of the acetabulum or the spine before the introduction of the autotransfuser was reviewed and compared with the group that had autotransfusion. An autologous blood predeposit program was used for twenty-five of fifty-two patients who had a procedure on the hip and for fifty-one of fifty-five patients who had an elective procedure on the spine. The mean rate of red blood-cell salvage using the autotransfuser was 60 per cent over-all. The mean transfusion requirements were significantly less (p less than 0.001) in all groups of patients in whom the autotransfuser was used. Use of the autotransfuser reduced the mean requirement for banked blood in patients who had a fracture of the acetabulum from 3.8 to 2.3 units per patient, and significantly reduced the mean need for banked blood in individuals who had trauma to the spine from 2.7 to 1.8 units per patient (p less than 0.01). The use of prebanked autologous blood further reduced the mean requirement for homologous blood from 2.4 to 0.8 unit per patient in those who had revision total hip arthroplasty (p less than 0.005), and from 3.6 to 0.4 unit per patient in those who had an elective procedure on the spine (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Transfusion↗
PubMed1979

[Observation of the so-called "anti-Chiari effect" subsequent to osteotomy of the pelvis in children (author's transl)].

Osteotomy of the pelvis according to Chiari is performed in the immediate vicinity of the acetabulum and the craniolateral corner of the acetabulum. In children, it will almost always involve damaging the important growth zones of the acetabulum. Depending on the site and extent of the osteotomy performed, the pathological growth kinetics will lead to varying defects. This pathology of the kinetics of growth is known as "Anti-Chiari effect".

Adolescent↗