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1.
J Am Acad Orthop Surg ; 30(22): 1090-1097, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36326830

RESUMO

INTRODUCTION: Studies have previously reported higher complication rates in elective total joint arthroplasty (TJA) for nonagenarians compared with younger cohorts. The purpose of this study was to assess whether nonagenarians were still at increased risk of complications and hospital readmissions by answering three questions: (1) Do nonagenarians have an increased risk of medical complications after TJA compared with octogenarians and septuagenarians? (2) Do nonagenarians have an increased risk of surgical complications after TJA compared with octogenarians and septuagenarians? (3) Do nonagenarians have an increased risk of hospital readmission after TJA compared with octogenarians and septuagenarians? METHODS: A total of 174 patients undergoing primary TJA between 2010 and 2017 were included; 58 nonagenarians (older than 90 years) were matched with 58 octogenarians (age 80 to 84 years) and 58 septuagenarians (age 70 to 74). Groups were matched by sex, diagnosis, surgeon, surgical joint, and year of surgery. Within each group, 31 patients (53%) underwent total hip arthroplasty and 27 patients (47%) underwent total knee arthroplasty. Comorbidities, American Society of Anesthesiologists physical status scores, and Charlson Comorbidity Index scores were captured preoperatively. Complications and readmissions occurring within 90 days postoperatively were evaluated. RESULTS: Nonagenarians had the highest rate of medical complications (33%) compared with octogenarians (14%) and septuagenarians (3%) (P < 0.001). Rates of surgical complications were not statistically different among nonagenarians (12%), octogenarians (9%), and septuagenarians (10%) (P = 0.830). Rates of hospital readmission were highest in nonagenarian patients (11%), but not statistically different compared with octogenarians (5%) or septuagenarians (2%) (P = 0.118). CONCLUSION: Nonagenarians were 3.1 times more likely to have a complication after TJA. The incidence of medical complications was highest in nonagenarians compared with octogenarians and septuagenarians, but rates of orthopaedic complications were similar. Nonagenarians who elect to proceed with TJA should be informed that they have an increased risk of postoperative medical complications compared with younger patients undergoing the same operation. LEVEL OF EVIDENCE: Level III, Therapeutic Study.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Idoso de 80 Anos ou mais , Humanos , Idoso , Artroplastia do Joelho/efeitos adversos , Nonagenários , Resultado do Tratamento , Artroplastia de Quadril/efeitos adversos , Readmissão do Paciente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco
2.
Clin Orthop Relat Res ; 480(4): 702-711, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35302971

RESUMO

BACKGROUND: Tranexamic acid (TXA) is often used to prevent excessive blood loss during bilateral TKA. Although it diminishes blood loss, TXA may have a potentially elevated thrombogenic risk with extra, unnecessary doses of TXA in this high-risk population. To date, the most efficacious dosing protocol in this setting has not yet been ascertained. QUESTIONS/PURPOSES: We compared one versus two doses of intravenous TXA in the setting of same-day bilateral TKA in terms of (1) perioperative blood loss that occurred during the hospital stay, (2) transfusion usage during the hospital stay, and (3) major complications occurring within 30 days of surgery. METHODS: Between August 2013 and October 2016, 309 patients underwent simultaneous bilateral TKA performed by one of five attending surgeons. During that time, indications for same-day bilateral TKA included bilateral knee pathology in which each knee was independently indicated for TKA and the patient preferred bilateral simultaneous TKAs versus staged bilateral surgeries. Patients who had cardiac disease or an American Society for Anesthesiologists physical classification score of greater than 2 were not generally indicated for bilateral simultaneous TKAs. After preoperative clearance from the primary physician and/or specialists as necessary, the decision for bilateral TKA was at the judgment of the operating surgeons. Input from anesthesia occurred at the time of the surgery as the procedure was performed in a sequential fashion allowing for the surgery to be restrained to a single limb if anesthesia identified concerns at the completion of the first TKA. The current retrospective, comparative series compared generally sequential groups in terms of TXA usage. Between August 2013 and July 2015, we used two TXA doses. Patients received 1 g of intravenous TXA as a bolus immediately after the last tourniquet release and were given a 1-g intravenous bolus 6 hours after the initial dose. A total of 167 patients were treated with this approach, of whom 96% (161) are fully analyzed here. Between August 2015 and October 2016, our approach changed to a single TXA dose. The dosing regimen change occurred as a group decision for change of practice and occurred mid-year to coincide with the fellowship year cycle. Patients received a 1-g bolus of intravenous TXA immediately after the final tourniquet release. A total of 105 patients were treated with this approach, of whom 89% (93) are fully analyzed here. An additional 37 patients were excluded because they did not receive any TXA because of a medical contraindication such as history of venous thromboembolism, history of thrombotic stroke, cardiac stent in the past 2 years, atrial fibrillation, or long-term anticoagulation therapy. We compared patients who received one versus two doses in terms of blood loss, transfusion usage, and 30-day major complications. The mean age was 65 years for patients receiving one dose and 67 years for patients receiving two doses (p = 0.17). The one-dose group comprised 67% (62 of 93) women and the two-dose group comprised 61% (98 of 161) women (p = 0.36). Blood loss was defined as change in the hemoglobin level (the last recorded value before discharge subtracted from the preoperative value). During the study period, the decision to transfuse was based on a hemoglobin level less than 8.0 g/dL or at higher levels for symptomatic patients, patients with cardiac disease, or at the discretion of the attending surgeon. We defined complications as major medical events that included cerebrovascular accidents, myocardial infarction, deep vein thrombosis, and pulmonary embolism. RESULTS: With the numbers available, there was no difference in blood loss between patients treated with one and those treated with two doses of TXA (mean hemoglobin decrease -3.5 ± 1.2 g/dL versus -3.5 ± 1.0 g/dL, respectively; mean difference 0.03 g/dL [95% CI -0.2 to 0.3 g/dL]; p = 0.80). No patient in either group received a transfusion. There was no difference in the proportion of patients in either group who experienced a cerebrovascular accident (0% [0 of 93] versus 1% [1 of 161]; p > 0.99), deep vein thrombosis (1% [1 of 93] versus 0% [0 of 161]; p = 0.37), or pulmonary embolism (1% [1 of 93] versus 1% [1 of 161]; p > 0.99). No patient in either the one-dose or two-dose TXA groups experienced a myocardial infarction. CONCLUSION: The findings of this study suggest that a single dose of intravenous TXA may be adequate to control excessive blood loss and reduce blood transfusion in simultaneous bilateral TKA. Despite its short half-life, TXA still appears to be effective in this demanding procedure without requiring prolonged plasma concentrations obtained from multiple doses. Additional high-quality studies are still needed to determine the most appropriate dosing regimen. LEVEL OF EVIDENCE: Level III, therapeutic study.


Assuntos
Antifibrinolíticos , Artroplastia do Joelho , Cardiopatias , Infarto do Miocárdio , Embolia Pulmonar , Ácido Tranexâmico , Trombose Venosa , Administração Intravenosa , Idoso , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue , Feminino , Cardiopatias/etiologia , Hemoglobinas , Humanos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/tratamento farmacológico , Embolia Pulmonar/etiologia , Estudos Retrospectivos , Trombose Venosa/etiologia
3.
Hip Int ; 32(6): 771-778, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33736475

RESUMO

BACKGROUND: Despite the high success rate of total hip arthroplasty (THA), new implant technologies continue to be developed. Although potentially useful, such novel developments may result in unintended consequences, leading to revision surgery, often prematurely. In several instances, new technology that appeared promising was later found to be inferior to existing technology and resulting in early revision surgery. Additionally, technical surgical errors may also lead to early revisions. Some have argued that revisions related to such phenomena are potentially avoidable. The present analysis investigates to what extent the contribution of "failed new technology" and "technical errors" contributes to the revision burden and to the need for premature revision arthroplasty. METHODS: We retrospectively analysed 432 revision THAs and categorised them as either "late revisions" based on survivorship of 10 years or "premature revisions". Among both cohorts, we determined what percentage of revisions were potentially avoidable and due to failed novel technologies and technical errors, and what percent were "unavoidable". RESULTS: Of the 432 revisions, 267 (62%) were considered premature and 38% were considered late. Of the premature revisions, 108 were considered potentially avoidable (81 failed novel technologies, 27 technical errors). CONCLUSIONS: Our data demonstrates that new technology and surgical techniques can result in premature failure of THA. Surgeons should take caution when incorporating new implant technology or surgical techniques into their practice.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Falha de Prótese , Estudos Retrospectivos , Desenho de Prótese , Reoperação , Tecnologia , Fatores de Risco
4.
J Surg Orthop Adv ; 29(4): 216-218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33416480

RESUMO

Although the vast majority of arthroplasty surgeons allow patients to return to participation in golf following total knee arthroplasty (TKA) and total hip arthroplasty (THA), there is relatively little published data regarding how TKA or THA affects a patient's golfing ability. The purpose of this study was to determine how golfers' handicaps change following TKA and THA. We mailed a questionnaire to patients who had underwent primary TKA or THA at our institution and asked whether they played golf and for their golf handicap information network (GHIN) number. We then obtained handicap data for each patient that provided a GHIN number. Handicap increased 0.9 strokes 1 year following THA; however, this difference was not statistically significant (p = 0.20). Handicap increased 0.3 strokes 1 year following TKA; however, this difference was not statistically significant (p = 0.29). Our study demonstrates that despite improved implants, surgical techniques, and rehabilitation protocols that golf handicap does not change significantly following lower extremity total joint arthroplasty (TJA). (Journal of Surgical Orthopaedic Advances 29(4):216-218, 2020).


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Golfe , Humanos , Extremidade Inferior , Inquéritos e Questionários
5.
J Am Acad Orthop Surg ; 28(10): e440-e447, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31567897

RESUMO

INTRODUCTION: Historically, hip precautions have been prescribed after total hip arthroplasty (THA) to limit certain motions felt to place the arthroplasty construct in a position at increased risk for dislocation. This study aimed to determine whether relaxed hip precautions after primary THA done via a posterolateral approach resulted in a higher early dislocation rate compared with standard hip precautions. METHODS: The hip precaution protocol was changed from standard to relaxed at our institution for all patients with THA in December 2016. One cohort had THA in the 18 months before the protocol change and had standard hip precautions, and the second cohort had THA in the 18 months after the protocol change and had relaxed precautions. We determined the early dislocation rate (within 3 months postoperatively) for both cohorts and controlled for selected demographic and surgical details. RESULTS: The standard precaution group included 597 primary THAs and the relaxed precaution group included 692 hips. No notable differences were found between the groups in terms of age at surgery, body mass index, sex, laterality, or diagnosis. Early dislocation occurred in seven hips (1.2%) in the standard precaution cohort and in nine hips (1.4%) in the relaxed precaution cohort. This difference was not statistically significant (P = 0.77). DISCUSSION: The results of our study suggest that well-trained, high-volume surgeons may potentially relax hip precautions prescribed to the patients after primary THA done via a posterolateral approach without subjecting patients to a markedly higher incidence of dislocation. However, unlike previous studies, this study controlled for femoral head size, which is a well-known confounder for dislocation risk.


Assuntos
Artroplastia de Quadril/efeitos adversos , Luxação do Quadril/etiologia , Luxação do Quadril/prevenção & controle , Quadril/fisiopatologia , Movimento , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Idoso , Feminino , Luxação do Quadril/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultados Negativos , Complicações Pós-Operatórias/epidemiologia , Risco
6.
Arthroplast Today ; 4(1): 71-73, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29564375

RESUMO

Persistent wound drainage after total joint arthroplasty can potentiate periprosthetic joint infection. Although current recommendations are to treat persistent wound drainage with surgical debridement, we believe nonoperative treatment may be successful in selected patients. We performed a retrospective analysis of 25 persistently draining hip and knee arthroplasty wounds treated with a protocol consisting of a combination of surgical site aspiration, closure of open wound edges, cessation of anticoagulants, activity modification, and antibiotics (in select patients). Wound drainage ceased in 24 of 25 wounds treated with this protocol. One patient who continued to drain for 3 more days was successfully treated with surgical debridement and evacuation of hematoma. No patient developed infection. We believe this protocol can be successful in many arthroplasty patients.

7.
Knee ; 21(1): 168-71, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24161449

RESUMO

BACKGROUND: Bearing surface wear remains a potential concern amongst younger patients undergoing total knee arthroplasty (TKA). Because of the potential for lower prosthetic wear rates, oxidized zirconium is a potentially attractive bearing surface for TKA in young, active patients. This material is also well suited for patients with suspected nickel sensitivities as it has no measurable nickel content, in contrast to standard femoral bearings made of cobalt-chromium alloys. Although in vitro testing on knee wear simulators has demonstrated favorable wear characteristics of oxidized zirconium compared to traditional cobalt-chrome bearings, in vivo clinical outcome data with this novel bearing surface are sparse. METHODS: We retrospectively reviewed 109 consecutive TKAs in 82 patients at a minimum of five years postoperatively to determine prosthetic survivorship and to assess whether any adverse clinical consequences could be attributed to this bearing. Knees were evaluated with Knee Society scores, UCLA activity scores, clinical examinations, and radiographs. The mean age for this cohort was 58.7 years. RESULTS: Survivorship free of bearing related complications was 100% at a minimum of five years post-surgery. There were no revisions for loosening, osteolysis, implant failure, or deep infection. There were no knees with radiographic failure, visible wear, loosening, or osteolysis. CONCLUSION: Oxidized zirconium remains an attractive option for patients with nickel sensitivities and in those patients at risk for prosthetic wear due to young age or high activity levels.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Avaliação de Resultados da Assistência ao Paciente , Zircônio , Adulto , Idoso , Artrite/cirurgia , Dermatite Alérgica de Contato/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Níquel/efeitos adversos , Amplitude de Movimento Articular , Estudos Retrospectivos
8.
J Arthroplasty ; 29(3): 580-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24074889

RESUMO

Proper femoral and acetabular component position and leg length equality are important intraoperative considerations during total hip arthroplasty. Unfortunately, traditional surgical techniques often lead to suboptimal component position, and such deviations have been associated with increased rates of prosthetic wear, dislocation, component loosening, and patient dissatisfaction. Although surgical navigation has been shown to improve reproducibility of component alignment, such technology is not universally available and is associated with significant costs and additional surgical/anesthetic time. In the current study, we found that a routine intraoperative pelvic radiograph could successfully identify malpositioned components and leg length inequalities and could allow for successful correction of identified problems. Unexpected component malposition and leg length inequality occurred in only 1.5% of cases where an intraoperative pelvic radiograph was utilized.


Assuntos
Artroplastia de Quadril/métodos , Mau Alinhamento Ósseo/diagnóstico por imagem , Prótese de Quadril , Desigualdade de Membros Inferiores/diagnóstico por imagem , Ossos Pélvicos/diagnóstico por imagem , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Mau Alinhamento Ósseo/cirurgia , Feminino , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Articulação do Quadril/diagnóstico por imagem , Humanos , Desigualdade de Membros Inferiores/cirurgia , Masculino , Pessoa de Meia-Idade , Falha de Prótese , Radiografia , Adulto Jovem
9.
Am J Orthop (Belle Mead NJ) ; 42(8): 353-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24078952

RESUMO

Some patients have been less than satisfied with flexion after total knee arthroplasty (TKA). As early designs provided limited flexion, companies have developed high-flexion designs. We conducted a study to compare flexion between 2 standard and 3 high-flexion designs and to compare clinical and radiographic postoperative flexion. Clinical and radiographic measurements were obtained by 3 independent orthopedists. Clinical flexion, with the patient maximally bending his or her knee as far as possible, was measured with a goniometer, recorded, and compared with measurements from lateral radiographs of the knee in the same position. A total of 144 knees (108 patients) were included in the study. Mean preoperative flexion was 110° for both groups, and mean postoperative flexion was 111° clinically and 109° radiographically for the standard designs, and 114° clinically and 117° radiographically for the high-flexion designs (P<.05). The groups had similar preoperative and postoperative Knee Society knee and function scores. Measurements obtained by the 3 independent examiners were highly correlated. Compared with the standard designs, the highflexion designs demonstrated statistically significantly more flexion, though the clinical increase in flexion was relatively small (3º).


Assuntos
Artroplastia do Joelho/métodos , Articulação do Joelho/fisiopatologia , Prótese do Joelho , Osteoartrite do Joelho/fisiopatologia , Desenho de Prótese , Amplitude de Movimento Articular/fisiologia , Idoso , Feminino , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Período Pós-Operatório , Radiografia , Resultado do Tratamento
10.
Orthopedics ; 36(5): e676-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23672922

RESUMO

Acute ischemic stroke is a potentially catastrophic medical emergency. Recently, successful reversal of the neurologic deficits associated with major ischemic strokes has been accomplished in selected patients through the use of intravenous tissue plasminogen activator (tPA), an agent that can accomplish thrombolysis of arterial clots if given within the first few hours after the onset of stroke. Because tPA works by thrombolysis of fresh clots, a potential exists for catastrophic hemorrhage if given to acute postoperative patients. Therefore, the use of tPA has never been studied in postoperative patients, and the safety of the drug in postoperative patients is unknown.The author describes a patient who had an acute ischemic stroke 2 days after total hip arthroplasty who was successfully treated with tPA without major complications. The patient was 51 years old and developed progressive facial droop, right arm paralysis, and dysarthria 2 days after elective hip arthroplasty. Imaging confirmed occlusion of the left middle cerebral artery. Neurologic recovery was believed to be unlikely without tPA. After tPA administration, the patient had full neurologic recovery within minutes but did develop a large (nondraining) hematoma and severe ecchymosis at the surgical site; a drop in hematocrit required 3 units of packed red blood cell transfusion. The wound did not develop skin necrosis, infection, or compartment syndrome, and the hematoma resolved within several weeks without the need for surgical intervention.The author describes the patient's specific circumstances, the decision-making process behind the use of tPA, and the need for contingency plans in the event that severe uncontrolled hemorrhage occurs. This information may be useful if other surgeons are faced with the dilemma of a major stroke in acute postoperative patients.


Assuntos
Artroplastia de Quadril/efeitos adversos , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Osteoartrite do Quadril/complicações , Osteoartrite do Quadril/cirurgia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Ativador de Plasminogênio Tecidual/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
11.
J Arthroplasty ; 28(7): 1212-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23538122

RESUMO

Metal-on-metal (MoM) bearings for total hip arthroplasty (THA) have come under scrutiny with reports of high failure rates. Clinical outcome studies with several commercially available MoM THA bearings remain unreported. We evaluated 78 consecutive MoM THAs from a single manufacturer in 68 patients. Sixty-six received cobalt-chrome (CoCr) monoblock and 12 received modular titanium acetabular cups with internal CoCr liners. Femoral components were titanium with modular necks. At average 2.1 years postoperatively, 12 THAs (15.4%) demonstrated aseptic failure (10 revisions, 2 revision recommended). All revised hips demonstrated capsular necrosis with positive histology reaction for aseptic lymphocytic vasculitis-associated lesions/adverse local tissue reactions. Prosthetic instability following revision surgery was relatively common. Female gender was a strong risk factor for failure, though smaller cups were not. Both monoblock and modular components fared poorly. Corrosion was frequently observed around the proximal and distal end of the modular femoral necks.


Assuntos
Artroplastia de Quadril/instrumentação , Reação a Corpo Estranho/epidemiologia , Prótese de Quadril , Metais , Complicações Pós-Operatórias/epidemiologia , Desenho de Prótese , Falha de Prótese , Idoso , Cromo , Cobalto , Corrosão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Fatores de Risco , Fatores Sexuais , Titânio
12.
Orthopedics ; 35(10): e1472-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23027482

RESUMO

Postoperative flexion is an important factor in the outcome of total knee arthroplasty. Although normal activities of daily living require a minimum of 105° to 110° of flexion, patients from non-Western cultures often engage in activities such as kneeling and squatting that require higher flexion. The desire to achieve greater flexion serves as the driving force for prosthetic modifications, including high-flexion designs. Techniques used to measure knee flexion and knee position during measurement are not often described or are different depending on the examiner. The purpose of this study was to compare active (self) and passive (assisted) flexion after successful total knee arthroplasty for 5 prostheses (2 standard and 3 high-flexion) using clinical (goniometer) and radiographic (true lateral radiograph) measurement techniques by different independent examiners.At a mean follow-up of 2.7 years (range, 1-5.6 years), a total of 108 patients (144 total knee arthroplasties) had completed the study. Mean postoperative active flexion was 111° clinically and 109° radiographically for the standard designs and 114° clinically and 117° radiographically for the high-flexion designs. Adding passive flexion increased flexion to 115° clinically and 117° radiographically for the standard designs and 119° clinically and 124° radiographically for the high-flexion designs. Flexion differences between the 2 measurement techniques (active vs passive and clinically vs radiographically) were statistically significant (P<.05). These findings demonstrate the importance of describing how flexion is measured in studies and understanding how the method of measurement can affect the findings.


Assuntos
Artrografia/métodos , Artrometria Articular/métodos , Artroplastia do Joelho/métodos , Instabilidade Articular/diagnóstico , Instabilidade Articular/cirurgia , Idoso , Feminino , Humanos , Instabilidade Articular/fisiopatologia , Masculino , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
13.
J Arthroplasty ; 27(1): 116-21, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21908170

RESUMO

Metallic femoral components with ceramic articulating surfaces can substantially lower polyethylene (PE) wear during walking activities under conditions of normal knee alignment. It is unknown whether these types of components can maintain low wear rates under conditions of knee malalignment and the harsher kinematics associated with younger, athletically active patients. Wear was measured in non-cross-linked, ethylene oxide-sterilized PE inserts against oxidized zirconium or cobalt-chrome femoral components in a knee wear simulator. The vertical load was modified to replicate knee varus malalignment of 3°, and the range of tibial rotation was increased to 20°. Mean gravimetric and volumetric wear rate over 5 million cycles was 55% lower in the oxidized zirconium group. An oxidized zirconium femoral component can significantly reduce PE wear under simulated conditions of athletically active patients with modestly malaligned total knee arthroplasty prostheses.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Teste de Materiais , Polietileno , Zircônio , Fenômenos Biomecânicos , Oxirredução , Desenho de Prótese
14.
Knee ; 19(5): 560-3, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22206820

RESUMO

INTRODUCTION: Malalignment can result in poor clinical outcomes and increased wear. However, component malalignment can occur even when overall limb mechanical axis is within the normal anatomic range. We studied the effect of component malalignment in the presence of acceptable knee alignment in knee arthroplasty. METHODS: Sixteen tibial inserts retrieved at revision surgery were laser-mapped to measure wear. Average implantation duration was 7.7 years (range, 1 to 13). Early (postprimary) and final (prerevision) radiographs were analyzed for overall alignment (limb, femoral and tibial components) and osteolysis. RESULTS: The tibial components were initially aligned in a mean of 1.3 ± 1.7° varus (range, -1.5 to 4.5°), which increased to 3.2 ± 2.9° (range, -2.0 to 8.0°) at the time of revision (p=0.05). Tibial components initially placed in greater than 3° varus were associated with almost twice the volumetric penetration rate. Anatomic knee angles were 5.4 ± 0.9° valgus (range, 4.0 to 7.0°) in the post-primary radiographs and decreased in prerevision radiographs to 3.8 ± 2.6° (range, -1.0 to 7.5°), (p=0.04). DISCUSSION: Tibial varus was associated with increased medial compartment wear and total wear, thus affecting osteolysis in addition to local destruction of the bearing surface. Varus malalignment as low as 3° may result in accelerated wear, even if overall limb alignment is nearly ideal. These results indicate that tibial component alignment is an important factor associated with tibial tray subsidence and polyethylene wear even when limb alignment is neutral.


Assuntos
Artroplastia do Joelho/métodos , Mau Alinhamento Ósseo/etiologia , Fêmur , Articulação do Joelho/cirurgia , Osteólise/complicações , Polietilenos , Tíbia , Idoso , Mau Alinhamento Ósseo/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Osteólise/diagnóstico por imagem , Desenho de Prótese , Falha de Prótese , Radiografia , Reoperação , Estudos Retrospectivos , Propriedades de Superfície
15.
HSS J ; 7(2): 125-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22754411

RESUMO

Reported results of unicondylar knee arthroplasty (UKA) have mixed reviews in comparison with results of tri-compartmental knee arthroplasty (TKA). We prospectively evaluated the short-term results (2 years) of a newer design of a UKA implant (Preservation UKA) with a cobalt-chromium femoral component and an all polyethylene tibial component. Seventy-two patients with intact ligaments and loss of only medial articular cartilage received the Preservation prosthesis. Data were obtained using WOMAC, Knee Society score (KSS), and standard radiographs. WOMAC scores improved by 24 points and KSS improved by 33 points at 2-year follow-up. Mean flexion increased by 4° to126° at 2 years. On X-ray, only one patient had a radiolucency. No fractures occurred. Two knees were revised due to clinical symptoms of medial compartment pain. This 2-year follow-up study of the Preservation UKA shows promising early results. Long-term data would be necessary to compare results with TKA or other unicompartmental replacements.

16.
Orthopedics ; 33(9): 667, 2010 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-20839712

RESUMO

Interest in high-flexion total knee arthroplasty (TKA) prostheses designed to provide better postoperative range of motion (ROM) is widespread. We sought to determine whether changes in surface geometry of the tibial polyethylene insert could improve postoperative ROM in a consecutive series of patients undergoing TKA with retention of the posterior cruciate ligament (PCL). Two cohorts with Smith & Nephew (Memphis, Tennessee) Posterior Cruciate-Retaining Genesis II total knee prostheses were compared, 79 knees (65 patients) using standard tibial inserts and 85 knees (72 patients) using high-flexion inserts. The standard insert has a slightly raised posterior lip, whereas the high-flexion insert is recessed downward at the posterior margin to facilitate femoral rollback in flexion and eliminate impingement of the femoral component on the back of the polyethylene during rollback. Mean ROM 1 year postoperatively was 112.0° in patients receiving the standard insert and 119.3° in patients receiving the high-flexion insert. Preoperative ROM was similar in both groups. Flexion improvement in the high-flexion group over the standard insert group was statistically significant (P<.001). Final Knee Society Scores did not differ amongst patients receiving the standard and high-flexion inserts. Our study demonstrates that improved postoperative flexion can be achieved without changing surgical technique, bony cuts, or metallic prosthetic parts. This is the first report that we are aware of that documents improvement in ROM after PCL-retaining TKA through the use of high-flexion inserts.


Assuntos
Artroplastia do Joelho , Articulação do Joelho/fisiologia , Prótese do Joelho , Amplitude de Movimento Articular/fisiologia , Idoso , Estudos de Coortes , Feminino , Humanos , Articulação do Joelho/cirurgia , Masculino , Ligamento Cruzado Posterior , Desenho de Prótese , Estudos Retrospectivos
17.
Am J Orthop (Belle Mead NJ) ; 39(10): 495-500, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21290011

RESUMO

The effects of damaged femoral heads on long-term wear in total hip arthroplasties are not well known. In the study reported here, we compared the surface roughness of dislocated femoral heads, retrieved at time of revision, with that of heads revised for reasons other than dislocation. The dislocated heads, including 6 cobalt-chrome (Co-Cr), 2 oxidized zirconium, and 2 alumina (ceramic) heads, were compared with nondislocated Co-Cr and ceramic heads. Scratch marks on the dislocated Co-Cr and alumina heads were considerably smaller and shallow than those on the dislocated oxidized zirconium heads. Mean surface roughness of the dislocated heads was 368 nm (Co-Cr), 376 nm (alumina), and 2137 nm (oxidized zirconium). On the contrary, the mean surface roughness for nondislocated Co-Cr and alumina heads was 307.44 nm (outlier excluded) and 138.8 nm, respectively. Our data suggest that increased surface damage and roughness can occur after dislocation.


Assuntos
Artroplastia de Quadril , Cabeça do Fêmur , Prótese de Quadril , Falha de Prótese , Óxido de Alumínio , Artroplastia de Quadril/efeitos adversos , Ligas de Cromo , Humanos , Oxirredução , Reoperação , Propriedades de Superfície , Zircônio
18.
Clin Orthop Relat Res ; 468(1): 96-101, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19672671

RESUMO

UNLABELLED: Total knee arthroplasty (TKA) using a modular design allows isolated tibial polyethylene insert exchange (ITPIE) as a treatment option for isolated polyethylene failure. We asked whether ITPIE in selected patients would provide high survivorship and identified factors predicting success or failure. We retrospectively reviewed 42 patients (42 knees) who underwent ITPIE for instability, stiffness, or aseptic effusions after TKA. All patients had well-aligned and well-fixed components documented by radiographs and intraoperative evaluation. We determined whether patients had been revised and evaluated unrevised patients using the Knee Society rating system. The minimum followup was 2 years (average, 5.6 years; range, 2-11 years). Twelve patients (29%) underwent subsequent revision of their ITPIE (58% survivorship at 11 years). Average time to revision was 3 years. Although mean Knee Society scores improved, nine of the 30 unrevised patients (30%) had persistent pain at followup. Time from index TKA to ITPIE was associated with outcome; ITPIE less than 3 years from index TKA was 3.8 times more likely to undergo rerevision than ITPIE more than 3 years from index TKA. ITPIE for failed TKA is associated with unpredictable outcomes. ITPIE, even with well-defined and narrow indications, should be undertaken with caution. The longer the initial components performed successfully before ITPIE, the greater the likelihood of success after ITPIE. LEVEL OF EVIDENCE: Level II, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.


Assuntos
Artroplastia do Joelho/instrumentação , Prótese do Joelho , Osteoartrite do Joelho/cirurgia , Avaliação de Resultados em Cuidados de Saúde , Falha de Prótese , Tíbia/cirurgia , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho/métodos , Feminino , Indicadores Básicos de Saúde , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/fisiopatologia , Medição da Dor , Polietileno , Desenho de Prótese , Radiografia , Amplitude de Movimento Articular , Reoperação , Estudos Retrospectivos
19.
Clin Orthop Relat Res ; 468(2): 413-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19771485

RESUMO

UNLABELLED: The incidence of hip "squeak" associated with ceramic-on-ceramic bearings has been variably reported, ranging from 0.7% to 20.9%. We determined the patients' perception of squeaking in 306 patients (336 hips) in whom ceramic-on-ceramic total hip arthroplasties (THAs) were performed between 1997 and 2005. A questionnaire regarding hip noise was obtained by telephone. With a minimum followup of 2 years (mean, 3.9 years; range, 2-10 years), 290 patients (320 or 95% of the THAs) completed the questionnaire. Patients reported hip noise in 55 of the 320 THAs (17%); noise was perceived as squeak in 32 of the 320 (10%). Most squeaking hips (29 of 32) were pain-free and symptom-free. One patient was unhappy with his squeaking hip without pain. Our data suggest a much higher incidence of squeak as perceived by patients than previously reported. LEVEL OF EVIDENCE: Level II, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.


Assuntos
Artroplastia de Quadril/instrumentação , Cerâmica , Prótese de Quadril , Ruído , Artroplastia de Quadril/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Percepção , Desenho de Prótese , Qualidade de Vida , Estudos Retrospectivos , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
20.
HSS J ; 5(2): 117-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19308645

RESUMO

Rapidly destructive osteoarthritis (RDO) of the hip is a rare condition characterized by rapid joint degeneration and destruction similar to findings of infection, osteonecrosis, or Charcot disease but without a definitive diagnosis. The cause and natural history of RDO are unclear, but total hip arthroplasty has been utilized as a treatment modality due to the severity of the symptoms. We reviewed retrospectively the records of total hip arthroplasties performed between 1990 and 2003 and identified ten hips in eight patients who fit the profile of the diagnosis of RDO. The mean age at time of surgery was 70. Nine hips were treated with total hip arthroplasty with a hybrid configuration; one hip was treated with a non-cemented total hip arthroplasty. Average follow-up was 6 years with no radiographic evidence of acetabular loosening or osteolysis and no evidence of asymmetric cup wear. One femoral component had evidence of loosening but has not been revised. RDO is an idiopathic condition with no single diagnostic laboratory, pathological, or radiographic finding. A complete preoperative work-up for other causes of hip disease prior to arthroplasty for suspected RDO is necessary to rule out treatable disease. Our series of patients with RDO responded well to hybrid and non-cemented total hip arthroplasty with good clinical and radiographic results.

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