Total hip arthroplasty using S-ROM prosthesis for dysplastic hip

PURPOSE

The purpose of this study was to evaluate the clinical and radiological results of total hip arthroplasty using a proximal modular femoral stem in patients who had secondary coxarthrosis associated with a dysplastic hip.

MATERIALS AND METHODS

Forty-two patients (45 hips) with secondary coxarthrosis were evaluated after undergoing primary total hip arthroplasty using an S-ROM proximal modular femoral stem. The average follow-up was 80 months (range: 60 to 96 months). Clinical and radiological assessments were performed based on the Harris hip score and the radiological changes around the prosthesis.

RESULTS

The average Harris hip score improved from 52.2 points to 88.5 points. All femoral stems showed stable fixation; there were 37 cases by bony ingrowth and 8 cases by stable fibrous ingrowth. Neither osteolysis nor progressive radiolucent lines around the femoral stem were found at the last follow-up. Forty-one hips (91.9%) revealed excellent or good clinical results at the most recent follow-up.

CONCLUSION

For advanced secondary coxarthrosis, total hip arthroplasty with the use of the proximal modular femoral stem yielded good mid-term results with respect to the clinical and radiological criteria.

Hip dislocation in spina bifida: when is surgery required and what type of surgery should be performed?

Children with spina bifida develop a wide variety of congenital and acquired hip joint deformities. Among these are contractures, subluxation or dislocation. This paper will review both the overall orthopedic care of a spina bifida patient with hip problems and provide a focused review of surgery management of hip deformities. Special emphasis is placed on the indications and contraindications to surgery based on a literature review and the author's personal experience.

Challenges and solutions for total hip arthroplasty in treatment of patients with symptomatic sequelae of developmental dysplasia of the hip

Conditions that adversely affect a child's hip alignment, joint congruity, or articular surfaces often result in joint destruction associated with pain and motion limitation later in life. The usual culprits are developmental dysplasia of the hip (DDH), slipped capital femoral epiphysis, Legg-Calvé-Perthes disease, juvenile rheumatoid arthritis, infection, trauma, and neoplasm. In this review, we address DDH, the most common cause of secondary osteoarthritis of the hip. Symptomatic sequelae of DDH present challenges for total hip arthroplasty, including excessive proximal femoral anteversion, narrowing of the medullary canal, acetabular anteversion, verticality, hypoplasia and incongruity, pseudoacetabulum, and neurovascular shortening. Presiding corrective femoral and/or acetabular osteotomies, as well as retained hardware, further complicate total hip arthroplasty. This review emphasizes evaluation of hip morphology while considering reconstructive techniques and implants.

The effect of hospital volume on length of stay, re-admissions, and complications of total hip arthroplasty

BACKGROUND AND PURPOSE

Hospital volume has been suggested to be one of the best indicators of adverse orthopedic events in patients undergoing THR surgery. We therefore evaluated the effect of hospital volume on the length of stay, re-admissions, and complications of THR at the population level in Finland.

METHODS

30,266 THRs performed for primary osteoarthritis were identified from the Hospital Discharge Register. Hospitals were classified into 4 groups according to the number of THRs performed on an annual basis over the whole study period: 1-50 (group 1), 51-150 (group 2), 151-300 (group 3), and > 300 (group 4).

RESULTS

In 2005, the length of the period of surgical treatment was 5.5 days in group 4 and 6.8 days in group 1 (the reference group). During the whole study period (1998-2005), the length of surgical treatment period was shorter in group 4 than in group 1 (p < 0.001). The odds ratio for dislocations (0.7, 95% CI: 0.6-0.9) was lower in group 3 than in group 1.

INTERPRETATION

Hip replacements performed in high-volume hospitals reduce costs by shortening the length of stay, and they may reduce the dislocation rate.

Bone mineral densities in patients with developmental dysplasia of the hip

Bone mineral density (BMD) of the lumbar spine, ultradistal radius, and calcaneus were significantly higher in the developmental dysplasia of the hip (DDH) patients than in the controls. Therefore, our data suggest that BMDs at different skeletal sites are greater in patients with DDH than in healthy women.

INTRODUCTION

DDH has been acknowledged as a potentially preosteoarthritic condition that results in the development of hip osteoarthritis. Patients with DDH have been reported to have abnormal morphology of the pelvis and spine. Additional research, including that of bone quality, needs to be conducted to elucidate the pathogenetic mechanism of this disease. We therefore sought to determine whether BMD differs between healthy women and women with DDH.

METHODS

We measured BMD in 40 women who were scheduled to undergo pelvic osteotomy for DDH (average age, 45.3 years) and in 31 healthy women used as age-matched controls (average age, 47.5 years). BMDs of the lumbar spine, radius, and calcaneus were measured.

RESULTS

BMDs of the lumbar spine, ultradistal radius, and calcaneus were significantly higher in the DDH patients than in the controls.

CONCLUSIONS

Therefore, our data suggest that BMDs at different skeletal sites are greater in patients with DDH than in healthy women.

The multifaceted etiology of acetabular labral tears

Acetabular labral tears have been the focus of much attention in recent years. With the increased use of hip arthroscopy and magnetic resonance arthrography, the infrequent labral tear has proved to be more prevalent than previously thought. The majority of labral tears occur due to an underlying anatomic abnormality. Anatomic abnormalities that can lead to labral tears include femoracetabular impingement, acetabular retroversion, abnormal femoral head, Legg Calvé Perthes, slipped capital epiphysis, capsular laxity, and dysplasia of the hip. Tears in the labrum may lead to the advancement of osteoarthritis. Optimal management of a labral tear may involve addressing underlying anatomic abnormalities in addition to the labral tear itself.

[The retrospective analysis of good and poor results of the intertrochanteric osteotomy for hip osteoarthritis]

OBJECTIVES

To predict the final result of intertrochanteric osteotomy.

MATERIALS AND METHODS

56 hips in 53 patients after intertrochanteric osteotomy without any change in neck-shaft angle were enrolled into the analysis. 26 hips with a good result of intertrochanteric osteotomy were included into A group and 26 hips with a poor result were included into B group. The follow up was 5 to 11 years. Such preoperative parameters as: age and body weight of patients, severity of arthritis, sphericity of the head, joint space width, center-edge angle, pain severity, walking capacity, range of motion- were analyzed in both groups of patients. Survival of the hips was estimated with a Kaplan-Meyer survival curve.

RESULTS

At last follow up 27 hips (26 patients) were converted into hip prosthesis. The mean operative age of the patients in group A was 37.8 years and in group B 43.4 years. The severity of hip arthritis was similar in both groups of patients. Regular spherical head was found in 10 hips of group A and in 12 of B group. The center-edge angle was 15 degrees in group A and 18 degrees in group B. The joint space width was 2.6 mm in group A, and 2.5 mm in B group. Walking capacity, pain severity, range of motion of the affected hip was very similar in both groups of patients. Patients of group B had hip prosthesis already implanted 2.8 years after osteotomy.

CONCLUSIONS

No statistically significant difference was found between analyzed preoperative parameters in patients with good and poor results of intertrochanteric osteotomy. The final result of intertrochanteric osteotomy is not predictable.

Intermediate-term results after uncemented total hip arthroplasty for the treatment of developmental dysplasia of the hip

OBJECTIVES

We aim to evaluate the restoration of the hip and limb length in patients with osteoarthritis secondary to developmental dysplasia of the hip (DDH) using total hip arthroplasty (THA).

PATIENTS AND METHODS

Between February 1996 and September 2001, 65 hips in 55 patients (2 males, 53 females; mean age 48.6 years; range 37 to 60 years) with advanced osteoarthritis secondary to DDH underwent uncemented THA. According to the Hartofilakidis classification, 20, 27, and 18 hips were evaluated types I (dysplasia), II (subluxation), and III (dislocation), respectively. All of the acetabular cups were reconstructed in the original anatomic location. Structural autografts were used in seven hips to supplement the acetabular coverage. We evaluated all patients clinically and radiographically.

RESULTS

All of the patients were followed up for 7-12 years. Preoperatively, the Harris score averaged 52.5, 48.41, and 45.28 in types I to III, respectively. At the final follow-up, the Harris score averaged 89.65, 87.44, and 83.28, respectively. The difference between the pre- and postoperative scores was significant (p=0.0001). Preoperatively, 26 patients (47.27%) had slight limps (length difference <1 cm), eight (14.55%) had moderate limps (length difference 1-3 cm), and 21 (38.18%) had severe limps (length difference >3 cm). At their final follow-up, four (7.27%) had severe limps. The limps of all of the patients improved significantly (McNemar's test p=0.0001). We observed aseptic loosening and subsidence in six hips. In seven hips, we used a femoral head autograft for the superior acetabular defect. We performed femoral shortening osteotomies only for two (3.07%) type III hips.

CONCLUSION

In addition to the standard procedure, structural bone autografting, medialization of the cup, and placing the acetabular component in the true acetabulum are important factors for successful intermediate-term results.

[Total hip replacement for patients with end-stage osteoarthritis secondary to developmental dysplasia of the hip]

OBJECTIVE

To investigate the surgical techniques and clinical outcomes of total hip replacement for patients with end-stage osteoarthritis secondary to developmental dysplasia of the hip.

METHODS

From May 2004 to March 2008, a total of 36 total hip replacements were performed in 32 patients with end-stage osteoarthritis secondary to developmental dysplasia of the hip. The acetabulum cup was reconstructed in the corresponding anatomical position in all cases. Cemented components were used in 16 hips, and cementless components in the other 20 hips. The mean follow-up was 31.3 months. Clinical outcomes were determined with Harris hip score. Radiographs were taken after the surgery and in every follow-up examination for further reference.

RESULTS

All patients postoperatively gained a limb lengthening with an average of (3.4+/-1.3) cm. Three patients had complications, 2 had nondisplaced fractures of the proximal part of the femur,and 1 sciatic nerve palsy which disappeared after 3 months. There was no infection, dislocation and symptomatic deep vein thrombosis. Compared with preoperation, the mean Harris hip scores on the 3rd day, the 14th day after the operation and at the last follow-up were all improved significantly (all P<0.05). There was no loosening, migration, heterotopic ossification radiographically, and no revision during the follow-up.

CONCLUSION

Total hip replacement is an effective treatment for patients with end-stage osteoarthritis secondary to developmental dysplasia of the hip. The key is to place the acetabulum cup in the corresponding anatomical position, and choose proper prosthesises during the surgery.

Arthroscopy for labral tears in patients with developmental dysplasia of the hip: a cautionary note

Patients with developmental dysplasia of the hip may present with acetabular rim overloading, labral hypertrophy, and tear. Our hypothesis was that isolated arthroscopic treatment of labral tear is likely to fail in most patients. We investigated 34 patients who underwent at least one arthroscopy of the hip for labral tear. Developmental hip dysplasia or other morphologic abnormalities of the hip were confirmed in all patients. Arthroscopy failed to relieve pain in 24 patients. We observed accelerated arthritis in 14 patients and migration of the femoral head in 13 patients. Sixteen patients underwent further surgery (further surgeries included periacetabular osteotomy [6 patients], femoroacetabular osteoplasty [7 patients], and total hip arthroplasty [3 patients]). At the latest follow-up, all patients but one were pain-free. Patients with evidence of abnormal hip morphologies may not benefit from hip arthroscopy and isolated treatment of the labrum; in fact, the latter may accelerate the process of arthritis in some patients.

[Effect of total hip replacement on lumbago in unilateral developmental hip dysplasia]

OBJECTIVE

To assess the effect of total hip replacement on lumbago in patients with unilaterally developmental hip dysplasia.

METHODS

From January 2001 to January 2006, 39 adult patients with unilateral developmental hip dysplasia co-exiting lumbago were included. Among them, there were 32 females and 7 males, age from 38 years to 73 years. According to Crowe classification system, there were 4 in type I, 20 in type II,8 in type III and 7 in type IV. They were performed total hip replacement. The Harris Hip Score and the Oswestry Disability Index were used to evaluate hip and spine symptoms in same patient before and 3, 24 months after operation.

RESULTS

Thirty-nine patients were evaluated, both hip and spinal pain and function were significant improved. The mean Harris score increased from 44 to 84 (P < 0.01). The mean Oswestry Scores dropped from 36 to 25 (P < 0.01).

CONCLUSION

Spinal function and lumbago is improved after total hip replacement in patients with unilateral developmental hip dysplasia at 3 months, which is maintained and enhanced in 2 years.

[Reconstruction of the acetabular in the Crowe III dysplastic hip]

OBJECTIVE

To investigate the method and the outcome of the acetabular reconstruction in the Crowe III dysplastic hip.

METHODS

From January 2001 to June 2007, 43 cases (54 hips) were diagnosed osteoarthritis secondary to Crowe III dysplastic hip. Total hip arthroplasty was performed in all cases. The Harris score was 39 pre-operation. The method of the acetabular reconstruction included acetabular deepening (group A), medial-wall osteotomy (group B), femoral head bone grafting (group C). Radiography data and Harris score were taken to evaluate the clinical outcome.

RESULTS

The method of the acetabular reconstruction included acetabular deepening in 27 cases (34 hips), medial-wall osteotomy in 12 cases (15 hips), femoral head bone grafting in 4 cases (5 hips). Forty cases were followed up by the mean time of 29 months. The bone union time of the osteotomy and bone grafting were 4 - 5 months postoperation. In the three groups the obliquity angle of the cup were (41.0 +/- 7.5) degrees , (46.0 +/- 7.7) degrees , (39.0 +/- 11.0) degrees ; the anteversion angle of the cup were (10.0 +/- 2.8) degrees , (9.0 +/- 2.5) degrees , (4.0 +/- 1.9) degrees ; the rotation center of the hip was shift superiorly (8.4 +/- 3.6) mm, (7.3 +/- 2.6) mm, (1.2 +/- 0.5) mm; the rotation center of the hip were shift internally (7.0 +/- 1.5) mm, (9.9 +/- 1.7) mm, (-2.7 +/- 1.2) mm, and the Harris score were 89, 91, 86 at the follow up. The complication included deep venous thrombosis in 2 cases, pulmonary embolism in 2 cases, sciatic nerve palsy in 4 cases.

CONCLUSION

Acetabular deepening, medial-wall osteotomy, femoral head bone grafting can be used in reconstruction of the acetabular in the Crowe III dysplastic hip.

Bilateral incidence and severity of acetabular dysplasia of the hip

BACKGROUND

Most Japanese patients have secondary osteoarthritis, mainly due to developmental dislocation of the hip (DDH) or acetabular dysplasia (AD). However, the precise pathomechanism of AD remains unknown. The purpose of this study was to investigate the frequency of bilateral AD and determine the correlation of the severity of AD between the right and left hips.

METHODS

A total of 206 patients with prearthritis or early-stage osteoarthritis caused by AD were examined radiographically, and their history of treatment for DDH during infancy was reviewed. There were 187 women and 19 men included in the study, and the mean age at examination was 37.6 years (range 20-49 years).

RESULTS

A total of 174 patients (84%) had bilateral AD. In all, 72 (35%) of the 206 patients had a history of treatment for DDH (DDH group), and the remaining 134 (65%) had no history of DDH (non-DDH group). Bilateral AD was observed in 55 patients (76%) in the DDH group and 119 patients (89%) in the non-DDH group; the difference was significant. The center-edge angle, acetabular head index, acetabular angle, and acetabular roof angle showed positive correlations between the right and left sides in the non-DDH group. There was no correlation of the acetabular roof angle between the two sides in the DDH group.

CONCLUSIONS

A high rate of bilateral AD and a positive correlation of the severity of AD between the right and left hips were observed, especially in patients with no history of DDH. Our data suggest that in many patients AD occurred as a result of bone malformation involving bilateral hip joints. More research from a genetic standpoint is needed to elucidate the pathomechanism of this disease.

[Treatment of osteoarthritis secondary to acetabular dysplasia by total hip arthroplasty]

OBJECTIVE

To evaluate the flexibility of the treatment of osteoarthritis secondary to acetabular dysplasia by total hip arthroplasty (THA), in which the acetabular component is placed in the true acetabulum and femoral osteotomy is not performed.

METHODS

From January 1999 to December 2005, 35 THA procedures were performed in 32 patients with 35 hips, including 6 males with 7 hips and 26 females with 28 hips, with the average age of 53 years (ranging from 28 years to 72 years). On the basis of Crowe classification, type I included 10 patients with 11 hips, type II included 14 patients with 15 hips, type III included 5 patients with 6 hips, and type IV included 3 patients with 3 hips. All patients experienced severe pain and dysfunction. In 19 cases, the leg length discrepancy was from 3 cm to 6 cm. The Harris score was 41.49 +/- 10.13 before the operation. In all procedures, the soft tissue was released entirely and the acetabular component was placed in the true acetabulum, but femoral osteotomy was not performed.

RESULTS

The average operation time of unilateral THA was 50 minutes. All patients were given transfusion from 2 U to 4U. All incisions healed at the first stage. After the operation, the leg was lengthened 2-6 cm, and the two legs were equally long. The follow-up lasted for 12 to 60 months. The Harris score was 84.71 +/- 9.34 after the operation, showing statistically significant difference (P < 0.05). According to clinical outcomes and X-ray films, no dislocation, femoral fracture, femoral or sciatic nerve palsy was detected.

CONCLUSION

It is effective to use THA procedures for osteoarthritis secondary to acetabular dysplasia. If the soft tissue is released entirely, the leg will be lengthened 4-6 cm without nerve palsy.

Comparison of pelvic radiographs in weightbearing and supine positions

We asked whether radiographic angles and signs of hip osteoarthrosis differ between radiographs of the pelvis taken in standing and supine positions. We retrospectively reviewed the radiographs of 61 patients (72 hips) with developmental dislocation of the hip. The minimum followup after closed reduction was 15 years (mean, 44 years; range, 15-64 years). We used pelvic radiographs in supine and standing positions taken at the same time and determined the following parameters: minimal joint space width, acetabular roof obliquity (AC angle), depth of the acetabulum (ACM angle), and center-edge angle. Osteoarthrosis was assessed according to Kellgren and Lawrence. Two independent observers measured all radiographs manually with a goniometer. AC angle, center-edge angle, and minimum joint space width differed between the radiographs taken in supine and standing positions at followup, whereas osteoarthrosis grading and the ACM angle did not. The AC angle depended on patient position and predicted development of osteoarthrosis. The minimum joint space width was influenced by the radiographic position with greater values in the supine position. ACM angle and the osteoarthrosis grade according to Kellgren and Lawrence were unaffected by the patient's position.

LEVEL OF EVIDENCE

Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Operative tactics and results of treatment of patients with coxarthrosis secondary to congenital high luxation of hip joints

BACKGROUND

Treatment of the sequelae of congenital high luxation of the hip joint is a major challenge in prosthetic surgery, demanding from the operator thorough familiarity with the problem and experience in hop reconstructive surgery.

MATERIAL AND METHOD

The results of 4 years observation, of the treatment of 14 woman in the average age of 38 years old with 18 hip joints with congenital high luxation are presented. In all cases cementless total hip arthroplasty was made. Acetabular component of the prosthesis was implanted correctly and stable in its physiological placement. Femur was shortened average 4 cm and stabilized by cementless press-fit stem of prosthesis. The place of femur osteotomy was covered with autogenic spongy bone from resected caput of femur.

RESULTS

The union was achieved after average 10 weeks. In clinical assessment there were obtained 10 very good, 5 good and 3 satisfactory clinical results. There were no superficial or deep infections, no neurological disorders and no loosening of components of implanted prostheses observed.

CONCLUSIONS

1. Careful planning and carrying out the operative procedures allow to insert the acetabular component of the prosthesis in its physiological place and achieve good results. 2. Shortening of femur and repositioning of components of prosthesis in 90 degrees knee flexion and also position on broken bed after operative procedure allowed to avoid neurological disorders. 3. Cementless and hydroxyapatite-covered femoral component of the prosthesis correctly stabilize place of femur osteotomy.

[Morphological changes of proximal femur in patients with Crowe II/III developmental dysplasia of hip and their implication to total hip arthroplasty]

OBJECTIVE

To investigate the morphological changes of the proximal femur and their implication to the total hip arthroplasty in patients with Crowe II/III developmental dysplasia of the hip (DDH).

METHODS

The experimental group was composed of 15 hips in 14 patients (Crowe II, 9 hips; Crowe III, 6 hips ) with osteoarthritis secondary to Crowe II/III DDH (2 males, 12 females; age, 35-61 years). None of the patients had accepted any osteotomy treatment. The control group was composed of 15 normal hips in 15 patients with unilateral DDH (3 males, 12 females; age, 35-57 years). Twelve hips came from the experimental group and the other 3 came from the patients with unilateral Crowe I DDH. The femurs were examined with the CT scanning. The following parameters were measured: the height of the center of the femoral head (HCFH), the isthmus position (IP), the neck-shaft angle(NS), the anteversion angle, the canal flare index, and the canal width. Then, the analysis of the data was conducted.

RESULTS

HCFH and IP in the experimental group and the control group were 50.1 +/- 6.7 mm, 50.1 +/- 7.4 mm, and 107.4 +/- 21.5 mm, 108.7 +/- 18.1 mm, respectively, which had no significant difference between the two groups (P > 0.05). In the experimental group and the control group, the NS were 138.3 +/- 10.0 degrees and 126.7 +/- 5.7 degrees, the anteversion angles were 36.5 +/- 15.9 degrees and 18.8 +/- 5.4 degrees, and the canal flare indexes were 4.47 +/- 0.40 and 5.01 +/- 0.43. There was a significant difference between the two groups in the above 3 parameters (P < 0.05). As for the canal width of the femur, there was a significant difference in the interior/exterior widths and the anterior/posterior widths at the level of 2 cm above the lesser trochanter and 4 cm below the lesser trochanter between the two groups (P < 0.05); however, there was no significant difference in the canal width of the femur at the isthmus between the two groups (P > 0.05).

CONCLUSION

It is necessary to evaluate the morphology of the proximal femur before the total hip arthroplasty performed in patients with Crowe II /III DDH. The straight and smaller femoral prosthesis should be chosen and implanted in the proper anteversion position during operation.

Factors leading to osteoarthritis after eccentric rotational acetabular osteotomy

We performed eccentric rotational acetabular osteotomy consecutively in 273 hips in 248 patients with hip dysplasia. Twenty-one patients were male and 227 were female. The average age was 37.7 years at the time of the index operation. Twenty-two hips had no osteoarthritis, 129 had early osteoarthritis, 117 had advanced osteoarthritis, and five had end-stage osteoarthritis. Twenty-six hips also were treated with concomitant intertrochanteric valgus osteotomy. Patients were followed for a minimum of 5 years after surgery. The average Harris hip score improved from 71 points preoperatively to 92 points at the final followup. Nine hips were converted to total hip arthroplasty as a result of deterioration after surgery. Kaplan-Meier survivorship analysis 15 years after the index operation indicated 97% in pre- and early stages and 87% in advanced and end stages when the end point was total hip arthroplasty. Risk factors identified by multivariate analysis for development of osteoarthritis of the hip 5 years after the index operation were body mass index (24 kg/m2 or more), concomitant valgus osteotomy, operative year between 1989 and 1992, a postoperative center-edge angle of Wiberg less than 25 degrees , and a postoperative horizontal distance of the femoral head from the tear drop (40 mm or more).

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Rotational acetabular osteotomy through an ollier lateral u approach

Various methods of periacetabular osteotomy have been described. Since 1990, we have performed rotational acetabular osteotomy through an Ollier lateral U transtrochanteric approach without massive bone graft. This study investigated whether our technique could provide relief from symptoms, whether postoperative hip abductor weakness would be a critical complication, and whether appropriate acetabular coverage could be achieved. We followed in 101 patients (110 consecutive hips) with a mean age at surgery of 32.5 years and a minimum followup of 5 years (mean, 8.3 years; range, 5-16.2 years). Satisfactory results were found in 94 (85%) hips. A positive Trendelenburg sign was observed in eight (7%) hips at last followup. Appropriate postoperative coverage was provided with an average center-edge angle of 35 degrees . We found radiographic evidence of deterioration of osteoarthritic changes in 14 (13%) hips. Complications included deep infection (one patient); pulmonary embolism (one patient); osteonecrosis of the rotated acetabular fragment (two patients); and proximal displacement of the greater trochanter because of breakage of the polylevolactic acid screws (four patients). This procedure allows osseous cuts with good operative exposure and provides relief from symptoms in most painful dysplastic hips.

Acetabular morphology in bladder exstrophy complex

Little information is available concerning the acetabular morphology in adults with a history of bladder exstrophy. We documented the pelvic anatomy in adult patients with bladder exstrophy who never had prior surgery. We retrospectively reviewed 31 patients (62 hips) seen from 1976 to 2003 for urologic problems related to bladder exstrophy without adjunctive pelvic osteotomy. There were 18 males and 13 females with an average age of 30 years at last followup. Radiographs at final followup were analyzed for lateral center-edge angle, acetabular index, head extrusion, hip center of rotation, acetabular version, retroversion index, sacral width, and interteardrop distance. Most hips (60 hips) had no arthritis. The average lateral center-edge angle, ace-tabular index, and head extrusion index were 32 degrees, 5.7 degrees, and 0.266%, respectively. Fifty-eight percent of hips had a retroverted acetabulum and 42% were neutral or anteverted. The interteardrop distance averaged 154 mm. Most patients will not have early arthritis develop, and the majority of patients (58%) have retroverted orientation of the acetabulum.

Heterotopic gastric mucosa in gallbladder associated with kidney agenesis and congenital hip dysplasia

Heterotopic gastric tissue in the gallbladder is an extremely rare condition. There is not any specific clinical or laboratory finding and correct diagnosis is not possible before histopathological examination. Preoperative diagnosis usually resembles a polypoid Lesion or a fixed gallstone. We reported a 34-year-old female patient with heterotopic gastric mucosa in the gallbladder associated with congenital hip dysplasia and kidney agenesis. Laparoscopic cholecystectomy was performed and histopathology of the resected specimen showed that the "polyp" consisted of heterotopic gastric mucosa with glands of body and fundic type. Some cases of heterotopia in the gallbladder come from metaplasia, and may be one of the causes of gall bladder cancer. We discussed the clinical and histologic features of heterotopic gastric tissues and reviewed reported cases in the literature.

[Total hip arthroplasty in post-dysplastic hip arthritis. Can type and position of the acetabular component influence longevity of the prosthesis?]

PURPOSE OF THE STUDY

The aim of the study was a retrospective evaluation of our patients with post-dysplastic hips treated by cemented or non-cemented total hip arthroplasty (THA) in order to ascertain which type and position of the acetabular component was most effective.

MATERIAL

In the years 1999-2002, 111 THA procedures were performed in 93 patients, 76 women and 17 men, with post-dysplastic hip arthritis. The average age of the patients at the time of implantation was 52.6 years. On the basis of pre-operative radiographic findings, the patients' conditions were evaluated using the Hartofilakidis classification into three disease categories: dysplasia, low dislocation and high dislocation, and the patients were placed in two groups. Group 1 included 78 patients, and group 2 comprised 26 patients. None of our patients was classified as having high dislocation. Thirty-nine of these patients had previously undergone surgery for dysplastic hips.

METHODS

A total of 104 THAs were evaluated, because radiographic data was incomplete in seven cases. In addition to X-ray findings, the prosthesis type (cemented, hybrid, non-cemented), post-operative complications and signs of loosening were included in the evaluation. Clinical outcomes were assessed by the Harris score. The follow-up terminating on 31st December 2005 was 67 months on the average.

RESULTS

In group 1 patients, the average Harris score increased from 38.6 to 80.3 points and in group 2 patients from 35.5 to 84.9 points, mostly with excellent and good results. In 72.1 % of the hips, a press-fit acetabular component was implanted. In 55.8 % of the cases, the acetabular component was implanted off the anatomical center of rotation, into the high hip center, with the range from 9 to 20 mm and an average of 15 mm. The average limb lengthening was 2.5 cm, ranging from 1.0 to 3.5 cm.

CONCLUSIONS

Our results show that it is more effective to use non-cemented THA for post-dysplastic hips. The implantation of a noncemented acetabular component into the high center provides better covering of the cup with solid bone, without the necessity of cotyloplasty or structural graft use. Also, it does not markedly affect hip function or patients' subjective feelings.

[Femoro-acetabular impingement: a cause of groin pain and early hip osteoarthritis in younger patients]

In Denmark, approximately 7,000 hip joints are replaced by total hip arthroplasties annually. In 80% of the cases, the diagnosis is idiopathic end-stage osteoarthritis. Scientifically this is hardly acceptable. However, the last decade has witnessed a proliferative research in biomechanically important, often subtle, malformations of the hip joint which are thought to play an important role pathogenetically for the development of hip osteoarthritis and hip pain especially in younger, active patients. The common denominator for these malformations is that they cause femoro-acetabular impingement during hip flexion and internal rotation. Repetitive microtrauma damages the acetabular labrum and cartilage, and the osteoarthritic cascade is initiated in earnest. This review evaluates new research relating to this paradigm.

[Hip dysplasia: clinical assessment, radiologic evaluation and reference]

Hip dysplasia is a common congenital disorder, and identified as a source of pain, functional impairment and increased risk for development of osteoarthritis. Early diagnosis and reference is essential in symptomatic hip dysplasia, since patients may be candidates for joint preserving surgery. Assessment concentrates on history, physical examination and plain radiography. If radiography confirms the diagnosis (CE-angle < 25 degrees), the patient should be referred for expert evaluation. The assessment of hip dysplasia should be well-known to GPs, orthopaedics and radiologists.