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Nelson V Greidanus

Publications and source records attributed to Nelson V Greidanus.

14 recordsLinked to original sources
PubMed2007

Cementless two-stage exchange arthroplasty for infection after total hip arthroplasty.

We retrospectively reviewed all patients at one center with an infected total hip arthroplasty treated with 2-stage revision using cementless components for the second stage and the PROSTALAC articulated spacer at the first stage. Twenty-nine patients were reviewed and followed for at least 2 years postoperatively. An isolated Staphylococcus species was cultured in 76% (22/29) of patients. Three (10.3%) of 29 patients had recurrent infection at the site of the prosthesis. One of the 3 patients ultimately underwent a Girdlestone arthroplasty. Another patient was managed with irrigation and debridement, whereas the final patient was treated with intravenous antibiotics alone. Treatment of infection at the site of a hip arthroplasty with 2-stage revision using cementless components and an articulated spacer yields recurrence rates similar to revisions where at least one of the components at the second stage is fixed with antibiotic-loaded cement.

Adult↗
PubMed2006

Effect of retaining a patellar prosthesis on pain, functional, and satisfaction outcomes after revision total knee arthroplasty.

It remains controversial whether patients' pain, function, and satisfaction are affected in revision total knee arthroplasty by patellar prosthetic resurfacing. This is a retrospective, comparative cohort study to evaluate this. One hundred twenty-six patients who underwent total knee arthroplasty revision were identified. After revision, the presence or absence of a patellar prosthesis was ascertained. At a minimum of 2 years' follow-up, pain and function were assessed by Western Ontario and McMaster Universities Osteoarthritis Index, Oxford-12, Short-Form 12, and patient satisfaction questionnaires in 110 patients (58 with patellar component, 52 bony shell). Univariate and multivariate analyses demonstrated no significant difference between the 2 cohorts for Western Ontario and McMaster Universities Osteoarthritis Index pain, function, Oxford-12, and satisfaction outcomes. The absence of a patellar prosthesis does not appear to significantly affect pain, function, or satisfaction outcomes after revision total knee arthroplasty.

Aged↗
PubMed2005

Trochanteric osteotomies in revision total hip arthroplasty: contemporary techniques and results.

Revision total hip arthroplasty (THA) presents several challenges to the orthopaedic surgeon and typically requires the use of a more extensile surgical approach. Osteotomy of the greater trochanter can be considered as the ultimate extensile exposure in revision THA. The methods of trochanteric osteotomy can be categorized into three types: the standard trochanteric osteotomy, the trochanteric slide, and the extended trochanteric osteotomy. Although the standard osteotomy and trochanteric slide osteotomy provide excellent acetabular exposure, in the revision setting they are frequently associated with an unacceptably high rate of nonunion and proximal migration of the trochanteric fragment. The extended trochanteric osteotomy (ETO) has increased in popularity as the number and complexity of revision THAs continue to increase. Two commonly used techniques are the ETO via a posterolateral approach or via a modified direct lateral approach. Both techniques provide wide exposure of the acetabulum, facilitate femoral component exposure and removal, aid in canal preparation and femoral reconstruction, and allow for correction of proximal femoral deformity. The osteotomy fragment is easily secured and may be advanced distally to achieve proper tensioning of the abductors. Recent literature demonstrates that the ETO has a relatively low rate of nonunion and is associated with fewer intraoperative femoral fractures or cortical perforations, as well as decreased surgical time.

Arthroplasty, Replacement, Hip↗
PubMed2004

Patient satisfaction and functional status after aseptic versus septic revision total knee arthroplasty using the PROSTALAC articulating spacer.

This study compared the functional results of an articulating antibiotic spacer for 2-stage revision knee arthroplasty for infection, to the functional results of aseptic revision. One hundred twenty-five patients who underwent revision of total knee arthroplasty for infection and aseptic loosening were identified. All of the patients with infection were treated with the PROSTALAC system (DePuy). At a minimum 2-year follow-up, WOMAC, Oxford-12, SF-12, patient satisfaction data, Harris Hip Score knee scores, and range of motion were assessed. The 2 cohorts (4 deaths in total, leaving 54 septic, 57 aseptic) were equivalent for age, gender, and comorbidity scores. At a mean of 41 months, none of the outcomes were significantly worse for the septic group, which had 2 recurrences of infection (4%). The satisfactory functional results of the PROSTALAC system may be related to the design features.

Anti-Bacterial Agents↗
PubMed2004

Intraoperative fracture of the femur in revision total hip arthroplasty with a diaphyseal fitting stem.

BACKGROUND: In revision total hip arthroplasty, intraoperative split fractures and cortical perforation fractures are becoming a more common concern with the increasing use of diaphyseal fitting cementless stems. The purpose of this study was to evaluate the risk factors and frequency of intraoperative fractures with the use of these stems and their effect on radiographic and functional outcomes. METHODS: We performed a retrospective case-control study of 211 consecutive patients who had undergone revision hip arthroplasty with a diaphyseal fitting cementless stem between December 1998 and March 2002. Sixty-four patients sustained an intraoperative fracture of the femur. One hundred and fifteen patients were followed for a minimum of two years; function was analyzed with self-administered outcome questionnaires, and radiographs were evaluated for evidence of bone ingrowth into the femoral stem. RESULTS: Risk factors associated with an intraoperative fracture were a substantial degree of preoperative bone loss, a low femoral cortex-to-canal ratio, underreaming of the cortex, and the use of a large-diameter stem. The majority of the diaphyseal undisplaced linear fractures occurred at the distal end of an extended trochanteric osteotomy during stem insertion. Fracture due to cortical perforation occurred most often during cement removal. These intraoperative fractures had no significant effect on the functional outcome or radiographic evidence of bone ingrowth. CONCLUSIONS: There was a surprisingly high rate of intraoperative femoral fractures associated with the use of a diaphyseal fitting stem in revision total hip arthroplasty. Identification of risk factors such as preoperative bone loss and a low cortex-to-canal ratio may permit planning to avoid such fractures. However, the final functional and radiographic outcomes appear to have been unaffected by the fracture when it had been managed appropriately. LEVEL OF EVIDENCE: Prognostic study, Level II-1 (retrospective cohort study). See Instructions to Authors for a complete description of levels of evidence.

Activities of Daily Living↗
PubMed2004

Cable plates and onlay allografts in periprosthetic femoral fractures after hip replacement: laboratory and clinical observations.

Fractures of the femur after total hip replacement are an increasingly common and technically challenging problem. The results of nonsurgical treatment are poor. When the general condition of the patient allows, these injuries should be treated surgically. Several surgical treatments can be used to treat these fractures, and classification of the fracture assists the surgeon in the choice of procedure. Over the past decade, cable plate fixation systems and onlay strut allografts have become two of the most commonly used methods of fixation for fractures associated with hip prostheses. The ideal method of fixation is yet to be determined. However, laboratory studies have shown that dual fixation using either a lateral plate and anterior strut graft or two strut grafts produces the strongest construct. Cables rather than smooth wires should be used for fixation, and fixation strength increases with the number of cables used. The use of screws proximally produces a strong fixation but there are theoretical disadvantages to using screws around a femoral implant. Clinical data show high rates of fracture union using cable plate fixation, cortical onlay allograft fixation, and combined fixation methods for fractures that occur around well-fixed implants. Results have been less encouraging when these techniques have been used to fix fractures around prostheses that are either loose or malaligned; such fractures are better managed by revision of the femoral component to a long-stemmed device. Care should also be taken when there has been previous periosteal stripping of the femur because this may predispose to fracture nonunion. Periprosthetic fractures of the femur are a complex surgical problem and require specialized training in a range of surgical techniques.

Arthroplasty, Replacement, Hip↗
PubMed2004

Extended trochanteric osteotomy: planning, surgical technique, and pitfalls.

The extended trochanteric osteotomy is appropriate for a number of surgical indications. It facilitates removal of well-fixed cement mantles with a loose or well-fixed stem and of extensively porous-coated or tapered cementless stems. This exposure is particularly valuable in the presence of varus remodeling of the proximal femur, permitting correction of proximal femoral deformity and reducing the risk of fracture of the greater trochanter. It is also indicated in the removal of a well-fixed cemented stem that is complicated by infection, where it is vital to extract all foreign material for successful eradication of the infection. In addition, when the osteotomy is required for femoral exposure, it enhances acetabular exposure to allow even the most complex reconstruction. Also, as the soft-tissue attachments to the bone fragment are preserved in this approach, abductor muscle tension can be adjusted.

Arthroplasty, Replacement, Hip↗
PubMed2004

Cementing constrained acetabular liners in revision hip replacement: clinical and laboratory observations.

During revision hip arthroplasty, removal of a well-fixed, ingrown metal acetabular component may not be possible. Therefore, a new polyethylene liner can be cemented into the existing shell via the cement locking mechanism. This technique is well recognized, and the cement locking mechanism has proved to be sufficiently strong and durable for clinical use. A constrained polyethylene liner is designed to reduce the risk of hip dislocation by capturing the femoral head. However, there are increased shear forces created at the liner interface as the dislocation is resisted. If a constrained liner is cemented into an ingrown acetabular component, then there is the theoretical risk that these increased shear forces will damage the cement locking mechanism, thus leading to failure of the construct. There are a few clinical series in which a constrained liner has been used with the cement locking mechanism. Overall, the failure rate of the cement locking mechanism is no greater if a constrained liner instead of a standard liner is used. The cement locking mechanism can be strengthened by roughening the backside of a smooth polyethylene liner to improve the cement-polyethylene interface, or by using an all-polyethylene acetabular component that is designed to be used with cement. Whether a smooth metal shell needs to be roughened as well is a matter of debate.

Arthroplasty, Replacement, Hip↗
PubMed2003

Patient satisfaction and functional status after treatment of infection at the site of a total knee arthroplasty with use of the PROSTALAC articulating spacer.

BACKGROUND: Two-stage exchange arthroplasty remains the standard treatment of infection at the site of a total knee arthroplasty. The clinical and functional outcomes associated with the use of an articulating antibiotic spacer for two-stage revision for infection are not well established. We conducted a retrospective study to evaluate the outcomes associated with the use of the PROSTALAC articulating spacer between the first and second stages. METHODS: Fifty-eight patients underwent two-stage revision total knee arthroplasty for infection between January 1997 and December 1999. Of these, fifty-four were alive at the time of follow-up and forty-seven were available for inclusion in the present retrospective study. In all patients, a prosthesis of antibiotic-loaded acrylic cement (the PROSTALAC system) was implanted during the first stage after débridement. The amount of osteolysis that occurred between the stages and the range of motion of the knee joint were measured. After two years of follow-up, outcomes were assessed with use of the WOMAC, Oxford-12, and SF-12 instruments as well as a satisfaction questionnaire. RESULTS: At a minimum of two years (average, forty-one months) after revision arthroplasty, two patients (4%) had had a recurrence of infection. The amount of bone loss was unchanged between stages, and the range of movement of the knee improved from 78.2 degrees before the first stage to 87.1 degrees at two years. The average normalized WOMAC function and pain scores were 68.9 and 77.1, respectively; the average Oxford-12 score was 67.3; the average SF-12 mental and physical scores were 53.7 and 41.2, respectively; and the average satisfaction score was 71.7. CONCLUSION: A revision operation for infection at the site of a total knee replacement with use of an articulating spacer was associated with reasonable function and satisfaction scores. These findings may be related to the articulating features of the PROSTALAC system, which permits full active movement of the knee in the early postoperative period.

Anti-Bacterial Agents↗
PubMed2003

The prevention of periprosthetic fractures of the femur during and after total hip arthroplasty.

The increasing prevalence of periprosthetic fractures of the femur associated with total hip arthroplasty (THA) is caused by several factors, including the increasing use of cementless prostheses in both primary and revision procedure, the rise in THAs in younger patients, who are more at risk of high-energy trauma, and the increasing longevity of elderly patients after THA. With approximately 200,000 THAs performed annually in North America, fracture prevention is extremely important for the individual patient and has a significant impact on the health care system.

Arthroplasty, Replacement, Hip↗
PubMed2003

Principles of management and results of treating the fractured femur during and after total hip arthroplasty.

The management of fractures of the femur during and after total hip arthroplasty can be difficult, and treatment can be fraught with complications. The ideal scenario would be one in which these fractures are prevented. It is important that the surgeon has a through understanding of the principles of managing these fractures and has access to a variety of fixation and prosthetic devices and allograft bone when necessary in order to provide the best treatment. Because periprosthetic fractures range from the very simple (requiring no surgical intervention) to the complex (requiring major revision), a classification system of these fractures aids in understanding both the principles of management and results of treatment.

Arthroplasty, Replacement, Hip↗
PubMed2003

Cementless revision for infection following total hip arthroplasty.

Eradication of chronic infection complicating total hip arthroplasty requires removal of all infected, devitalized and foreign tissue, including the arthroplasty components. Reimplantation into a sterile bed is the goal of treatment in most patients and successful reimplantation yields better functional results than excision arthroplasty. Reimplantation may be performed at the same stage as débridement as part of a single-stage procedure, using cemented components with antibiotic-loaded cement. Alternatively, a two-stage procedure may be performed so that the débridement and reimplantation are separated by a period of antibiotic delivery, both locally and systemically. The results of these treatment regimens and the rationale for cementless reconstruction at the second stage of a two-stage treatment protocol are important considerations in the treatment of periprosthetic infection.

Anti-Bacterial Agents↗
PubMedDate not supplied

Computer-assisted femoral head resurfacing.

Femoral head resurfacing is re-emerging as a surgical option for younger patients who are not yet candidates for total hip replacement. However, this procedure is more difficult than total hip replacement, and the mechanical jigs typically used to align the implant produce significant variability in implant placement and take a significant amount of time to position properly. We propose that a computer-assisted surgical (CAS) technique could reduce implant variability with little or no increase in operative time. We describe a new CAS technique for this procedure and demonstrate in a cadaver study of five paired femurs that the CAS technique in the hands of a novice surgeon markedly reduced the varus/valgus variability of the implant relative to the pre-operative plan (2 degrees standard deviation for CAS versus 5 degrees for a mechanical jig operated by an expert surgeon). We also show that the mechanical jig resulted in significantly retroverted implant placement. There was no significant difference in operative time between the two techniques.

Arthroplasty, Replacement, Hip↗