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Javad Parvizi

Publications and source records attributed to Javad Parvizi.

At least 73 records · Page 4Linked to original sources
PubMed2004

A constrained liner cemented into a secure cementless acetabular shell.

BACKGROUND: Constrained acetabular components have been used to treat hips with recurrent instability following total hip arthroplasty and hips that demonstrate instability during revision surgery. In such hips, when a secure cementless acetabular shell is present, the surgeon can cement a constrained liner into the existing shell. The purpose of this study was to evaluate the clinical and radiographic outcome of this technique with use of a tripolar constrained liner that was cemented into a well-fixed cementless acetabular shell. METHODS: Between 1988 and 2000, constrained liners were cemented into thirty-one well-fixed cementless acetabular shells at three centers. The average age of the patients at the time of the index surgery was 72.1 years, and the indications for the procedure were recurrent hip instability in sixteen hips and intraoperative instability in fifteen hips. The patients were evaluated with respect to the clinical outcome and radiographic evidence of shell loosening and osteolysis. RESULTS: At an average duration of follow-up of 3.9 years, twenty-nine liners (94%) were securely fixed in the cementless shells and two constrained liners had failed. One liner failed because it separated from the cement, and one failed because of fracture of the capturing mechanism. Both hips were successfully revised with another cemented tripolar constrained liner. No acetabular component demonstrated radiographic evidence of progressive loosening or osteolysis. CONCLUSIONS: A constrained tripolar liner cemented into a secure, well-positioned cementless acetabular shell provides stability and durability at short-term follow-up. Careful attention to the preparation of the liner, the sizing of the component, and the cementing technique are likely to reduce the failure of this construct, which can be used for difficult cases of total hip instability.

Acetabulum↗
PubMed2004

Anterior femoroacetabular impingement: part I. Techniques of joint preserving surgery.

The exact pathomechanism responsible for osteoarthritis (OA) of the nondysplastic hip has remained unknown for many years. There is, however, emerging clinical evidence implicating femoroacetabular impingement as an etiologic factor for having early OA of the hip develop. Femoroacetabular impingement is an abutment conflict occurring between the proximal femur and the acetabular rim arising from morphologic abnormalities affecting the acetabulum or the proximal femur, or both. The repetitive mechanical conflict occurring during motion, particularly flexion and internal rotation, can lead to lesions of acetabular labrum and, even more serious, the adjacent acetabular cartilage. Surgical treatment of femoroacetabular impingement focuses on improving the clearance for hip motion and alleviation of femoral abutment against the acetabular rim. We will describe the rationale for the treatment of this condition, and discuss the technique of joint-preserving surgery.

Acetabulum↗
PubMed2004

Anterior femoroacetabular impingement: part II. Midterm results of surgical treatment.

Femoroacetabular impingement has been shown to cause labral and chondral lesions and leads to osteoarthrosis of the hip. With the elimination of the pathogenic cause we hope to prevent or delay additional degeneration of the hip. Fourteen men and five women with a mean age of 36 years (range, 21-52 years) were treated with a surgical dislocation and offset creation of the hip. The followup averaged 4.7 years (range, 4-5.2 years). Using the Merle d'Aubigné hip score, 13 hips were rated excellent to good, with the pain score improving from 2.9 points to 5.1 points at the latest followup. There was no avascular necrosis of the femoral head. Five of the 19 patients, two with Grade 2 osteoarthrosis, two with Grade 1 osteoarthrosis but severe acetabular cartilage damage, and one with untreated ossified labrum had subsequent total hip arthroplasty (THA). In the stable hips without subluxation of the head into the acetabular cartilage defect, no additional joint space narrowing occurred. Surgical dislocation with correction of femoroacetabular impingement yields good results in patients with early degenerative changes not exceeding Grade 1 osteoarthrosis. This procedure is not suitable for patients with advanced degenerative changes and extensive articular cartilage damage.

Acetabulum↗
PubMed2004

Total hip arthroplasty revision: a decade of change.

We studied the incidence, indications, and changing patterns of total hip arthroplasty (THA) revision by comparing all consecutive THA revisions performed at a single institution between July 1989 and June 1991 with all those performed at the same institution between January 2000 and December 2000. Aseptic loosening was the main reason for THA failure during both periods. Between the periods, the number of revisions for polyethylene wear, instability, and leg-length discrepancy increased, and the number of revisions for conversion of failed hemiarthoplasty to THA and for deep infection decreased significantly. We evaluate the reasons for these trends in an attempt to identify preventable causes of failure and to stimulate further research on prevention.

Arthroplasty, Replacement, Hip↗
PubMed2004

The effect of tibial polyethylene insert design on range of motion: evaluation of in vivo knee kinematics by a computerized navigation system during total knee arthroplasty.

Computer-assisted navigation for total knee arthroplasty offers the unique opportunity to assess in vivo knee kinematics during surgery and implement changes whenever appropriate. Using a computerized navigation system, the effect of 2 tibial polyethylene insert designs on knee kinematics in general and knee range of motion (ROM) in particular was evaluated in 37 knee arthroplasties in 30 patients. The Scorpioflex tibial insert was found to provide a significant increase in mean extension, mean flexion, and overall ROM of the knee compared with the standard tibial insert (P<.005) without affecting knee ligamentous balance. Navigation is a very effective and useful tool for intraoperative assessment of knee kinematics and accurate recording of ROM. Based on the information obtained from the navigation software, the surgeon can implement changes in selection of the knee components with beneficial effects in knee kinematics in general and knee ROM in particular. This may, in turn, translate to better clinical outcome of the knee arthroplasty.

Aged↗
PubMed2003

Total knee arthroplasty in post-traumatic arthrosis of the knee.

Total knee arthroplasty is an effective method of treatment for the majority of patients with a prior distal femoral or tibial plateau fracture and end-stage arthritis. There is a higher complication rate and overall poorer outcome when compared with routine primary total knee arthroplasty. In patients for whom the goals of optimal limb and implant alignment are achieved, the results are comparable with routine primary knee arthroplasty. Patients with suboptimal component positioning or residual deformity have a poorer outcome. The technical challenges encountered can require skills, implant systems, and methods usually reserved for complex revision arthroplasty.

Arthritis↗
PubMed2003

Total joint arthroplasty in human immunodeficiency virus-positive patients: an alarming rate of early failure.

The results of 21 total joint arthroplasties (13 knees, 8 hips) in 15 patients were reviewed. There were 13 men and 2 women with an average age of 38 years (range, 28 to 69 years). The mean follow-up period was 10.2 years (range, 2 to 23 years). Six patients died within an average of 10.6 years (range, 3 to 18 years) of joint arthroplasty. All patients died of AIDS. Deep infection developed in 6 joints. Knee Society scores improved significantly, but 13 repeat surgeries were required. An alarmingly high rate of complications was found after total knee and total hip arthroplasty in these patients with human immunodeficiency virus (HIV). Physicians and surgeons should be made aware of this high rate of complications after joint arthroplasty in patients with HIV and include a frank discussion of this information with their patients who are contemplating total joint arthroplasty.

Adult↗
PubMed2003

Total knee arthroplasty for neuropathic (Charcot) joints.

The clinical and radiographic results of 40 modern design condylar total knee arthroplasties (TKAs) in 29 patients with a confirmed diagnosis of Charcot joint were reviewed. The followup averaged 7.9 years (range, 2-15 years) for clinical and 6.4 years (range, 2-15) for radiographic surveillance. There was a significant improvement in Knee Society pain and function scores and ROM after knee arthroplasty. Extensive bone fragmentation and bone defect was present in 38 knees (95%). Metal wedge augments (10 knees, eight patient), autologous bone grafting (17 knees, 13 patients), and bone allografts (two knees, two patients) were used to reinforce the bony defects. Ligamentous instability necessitated the use of long stem components in 27 knees and rotating hinge prostheses in five knees. There were six reoperations for periprosthetic fracture (two knees, two patients), aseptic loosening (two knees, two patients), instability (one knee, one patient), and deep infection (one knee, one patient). Total knee arthroplasty may be offered to a select group of patients with end-stage neuropathic arthropathy. The basic principles of knee arthroplasty in restoring limb alignment, reinforcing bony defects by bone grafting or augmented prostheses, careful ligamentous balancing, and appropriate selection of constrained prostheses particularly are important in these patients. The technical challenges encountered during TKA in patients with neuropathic arthropathy, particularly in those with significant deformities, can require skills, implant systems, and methods usually reserved for complex revision arthroplasty.

Adult↗
PubMed2003

Femoroacetabular impingement: a cause for osteoarthritis of the hip.

A multitude of factors including biochemical, genetic, and acquired abnormalities may contribute to osteoarthritis of the hip. Although the pathomechanism of degenerative process affecting the dysplastic hip is well understood, the exact pathogenesis for idiopathic osteoarthritis has not been established. Based on clinical experience, with more than 600 surgical dislocations of the hip, allowing in situ inspection of the damage pattern and the dynamic proof of its origin, we propose femoroacetabular impingement as a mechanism for the development of early osteoarthritis for most nondysplastic hips. The concept focuses more on motion than on axial loading of the hip. Distinct clinical, radiographic, and intraoperative parameters can be used to confirm the diagnosis of this entity with timely delivery of treatment. Surgical treatment of femoroacetabular impingement focuses on improving the clearance for hip motion and alleviation of femoral abutment against the acetabular rim. It is proposed that early surgical intervention for treatment of femoroacetabular impingement, besides providing relief of symptoms, may decelerate the progression of the degenerative process for this group of young patients.

Acetabulum↗
PubMed2003

Demographic factors affecting long-term outcome of total hip arthroplasty.

We report the outcome of total hip arthroplasty (THA) in a cohort of patients with complete long-term radiographic and clinical followup information from our database of more than 48,000 primary hip replacements. The purpose of the study was to evaluate the influence of various demographic factors and patient comorbidity (Charnley classification) on the long-term outcome of THA. The cohort was comprised of 25,990 total hip replacements (THRs) in 10,243 (46.6%) men and 11,754 (53.4%) women with a median age of 66 years (range, 20-96 years) at the time of arthroplasty. Our study confirmed that THA has an impressive efficiency and reliability in alleviating pain and improving function for almost all of the patients. Furthermore, the results are enduring with more than 90% of patients being satisfied with the outcome at 15 years. Clinical outcome measures reach their maximum at 2 to 5 years after arthroplasty and thereafter they decline gradually. Furthermore, patient age, gender, body mass index, and main diagnosis all have an influence on specific functional parameters. The Charnley classification has the most profound effect on the overall functional status of patients.

Adult↗
PubMed2003

Total knee arthroplasty in patients with a prior fracture of the tibial plateau.

BACKGROUND: A fracture of the tibial plateau may predispose the knee to the development of posttraumatic arthritis. Malunion, intra-articular chondro-osseous defects, limb malalignment, retained internal fixation devices, and poor surrounding soft tissues may in turn compromise the outcome of total knee arthroplasty. The aim of our study was to evaluate the results of total knee arthroplasty in patients with a previous fracture of the tibial plateau. METHODS: The results of sixty-two condylar total knee arthroplasties performed with cement, from 1988 to 1999, in sixty-two patients with a previous fracture of the tibial plateau were reviewed. The fracture of the tibial plateau had been treated by open reduction and internal fixation in thirty-eight knees, external fixation in one knee, and nonoperatively in twenty-three knees. There were forty women and twenty-two men with an average age of sixty-three years at the time of the arthroplasty. Knee Society scores were recorded preoperatively and at the time of follow-up, at an average of 4.7 years, and complications were noted. No patient was lost to follow-up. RESULTS: The mean Knee Society scores improved significantly (p < 0.0001), from 43.9 points for pain and 52 points for function preoperatively to 82.9 and 84 points, respectively, at the time of the latest follow-up. There were thirteen reoperations, which included manipulation with the patient under anesthesia (five knees), wound revision (three knees), and component revision (five knees). There were six intraoperative complications (10%). A postoperative complication occurred in sixteen knees (26%). CONCLUSIONS: The vast majority of patients treated with total knee arthroplasty after a previous fracture of the tibial plateau have substantial improvement in function and relief of pain. However, these patients are at increased risk for perioperative complications, as evidenced by the high reoperation rate of 21% in this study.

Adult↗
PubMed2003

Corrective osteotomy for deformity in Paget disease.

BACKGROUND: Severe deformity resulting from Paget disease is not uncommon. Malalignment of the extremity may lead to intractable pain, mechanical overload of the neighboring joints, limitation of motion and function, and dysmorphic appearance. Although corrective osteotomy has been used to treat osseous deformities, the outcome of corrective osteotomy for long-bone deformities resulting from Paget disease remains largely unknown. METHODS: The results after twenty-five corrective osteotomies (twenty-two patients), performed between 1975 and 1995, in sixteen tibiae, eight femora, and one radius were evaluated. There were thirteen men and nine women with a mean age of sixty-seven years. The indication for osteotomy was pain in twenty limbs, recurrent stress fractures in three, and limitation of function in two. A variety of osteotomies and fixation methods were used. Two patients underwent simultaneous total hip arthroplasty and proximal femoral osteotomy. RESULTS: Twenty-three of twenty-five osteotomies healed with an average time to union of six months. Both nonunions were in patients who had been managed with intramedullary fixation. The time to union was significantly shorter in metaphyseal osteotomies fixed with plates than in diaphyseal osteotomies (p < 0.04). There was a substantial improvement in the deformities. Satisfaction was rated excellent or good by fourteen patients, fair by six, and poor by two. Complications included a pin-track infection in two patients, peroneal nerve palsy in one, and loss of fixation following external fixation in one. Disease activity, as measured by serum alkaline phosphatase level, and medical treatment with calcitonin and/or bisphosphonates did not have a significant impact on time to union. CONCLUSIONS: Corrective osteotomy for the treatment of severe deformity in Paget disease can be challenging and yet rewarding. A higher prevalence of complications was observed following intramedullary nailing and external fixation. Fracture-healing seems to be particularly protracted in diaphyseal osteotomies.

Adult↗
PubMed2003

Total knee arthroplasty in young patients with juvenile rheumatoid arthritis.

BACKGROUND: Juvenile rheumatoid arthritis is a disabling and destructive condition that commonly affects the knee during childhood. Total knee arthroplasty occasionally may be necessary for the treatment of end-stage disabling arthritis of the knee in young patients. There is a paucity of available data on the results of total knee arthroplasty in adolescents. We report our experience with total knee arthroplasty in patients under the age of twenty years who had juvenile rheumatoid arthritis. MATERIALS AND METHODS: We reviewed the results of twenty-five consecutive total knee arthroplasties that had been performed at our institution between 1982 to 1997 in thirteen patients (mean age, seventeen years) with juvenile rheumatoid arthritis. The average duration of clinical follow-up was 10.7 years, and the average duration of radiographic follow-up was 6.5 years. RESULTS: The mean Knee Society pain score improved markedly from 27.6 to 88.3 points, and the mean Knee Society function score improved modestly from 14.8 to 39.2 points. There was a slight improvement in the range of motion. Symptomatic and progressive radiolucent lines were noted in two knees, one of which was revised. Two knees (one patient) required exchange of the polyethylene liner at thirteen years. There were four additional reoperations, including manipulation under general anesthesia (two knees in one patient), lysis of adhesions (one knee), and extensor mechanism realignment (one knee). CONCLUSIONS: Despite a substantial number of postoperative complications, total knee arthroplasty provided excellent relief of pain and improvement in function in this group of adolescent patients with juvenile rheumatoid arthritis.

Adolescent↗
PubMed2003

Results of treatment of infection in both knees after bilateral total knee arthroplasty.

BACKGROUND: The purpose of this study was to review the results and complications of treatment of simultaneous infection of both knees after bilateral total knee arthroplasty. METHODS: Between 1976 and 1999, twenty-one patients with a mean age of seventy-one years were treated for simultaneous infection of both knees after bilateral total knee arthroplasty. Two patients died within two years, and one patient was lost to follow-up after one year. The remaining eighteen patients were followed for a mean of five years. At the time of presentation, all twenty-one patients had had symptoms for less than three weeks. Eleven patients (twenty-two knees) were treated with attempts at prosthetic salvage with surgical débridement and administration of suppressive antibiotics. Resection arthroplasty was performed as the initial treatment in ten patients (twenty knees). RESULTS: Of the ten patients treated with initial resection, seven patients (fourteen knees) underwent subsequent reimplantation. All fourteen knees were functioning well at the time of the latest follow-up, and none had been revised at a mean of two years after reimplantation. Of the eleven patients (twenty-two knees) who had been initially treated with prosthetic salvage, nine patients (eighteen knees) had a recurrence of the infection that required a reoperation (bilateral resection arthroplasty in seven patients, bilateral above-the-knee amputation in one patient, and repeat débridement of both knees in one patient). Two of the seven patients who had resection underwent reimplantation six weeks postoperatively, and the other five patients (ten knees) did not have reimplantation because of low functional demands and prohibitive medical comorbidity. CONCLUSION: We believe that treatment of simultaneous infection of both knees after bilateral total knee arthroplasty should consist of bilateral resection arthroplasty and delayed reimplantation after a period of intravenous administration of organism-specific antibiotics.

Aged↗
PubMed2003

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Adult↗
PubMed2003

Surgical treatment of limb-length discrepancy following total hip arthroplasty.

BACKGROUND: Although most patients with limb-length discrepancy following total hip arthroplasty have manageable symptoms, others may be disabled as a result of pain or functional impairment. In these patients, reoperation may be indicated to equalize the limb lengths. There is a paucity of published data regarding the outcome of surgical intervention to treat this problem. The purpose of the present study was to evaluate the results of revision hip surgery for the treatment of symptomatic limb-length discrepancy. METHODS: We retrospectively reviewed the clinical and radiographic records of patients who had undergone revision hip surgery at our institution for the treatment of a symptomatic limb-length discrepancy following a previous total hip arthroplasty. We identified twenty-one patients (twenty-one hips) who had an average age of sixty-six years at the time of revision hip arthroplasty. The average duration of follow-up was 2.8 years, and no patient was lost to follow-up. The indications for revision hip arthroplasty were severe hip and/or back pain for eleven patients, instability of the hip for eight, hip pain and ipsilateral limb paresthesia for one, and hip pain and ipsilateral foot drop for one. RESULTS: Revision arthroplasty was performed at a mean of eight months (range, six days to six years) after primary total hip replacement. The mean limb-length discrepancy at the time of the revision was 4 cm (range, 2 to 7 cm). Following revision arthroplasty, which involved revision of a malpositioned acetabular and/or femoral component, equalization of the limb lengths was achieved in fifteen patients. In the remaining six patients, the mean discrepancy had decreased to 1 cm. The mean Harris hip score improved significantly, from 56.5 points before the revision to 83.2 points at the time of the latest follow-up (p < 0.005). All but two patients were satisfied with the outcome of the revision surgery. CONCLUSIONS: Limb-length discrepancy following hip arthroplasty can be associated with pain, paresthesia, and hip instability. In these patients, careful evaluation of the position and orientation of the components may reveal the cause of the discrepancy. Revision arthroplasty may be indicated when a surgically correctable cause of limb-length discrepancy can be identified.

Acetabulum↗