The influence of preoperative deformity on valgus correction angle: an analysis of 503 total knee arthroplasties.
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The influence of preoperative deformity on valgus correction angle: an analysis of 503 total knee arthroplasties.
J Arthroplasty. 2013 Jan;28(1):20-7
Authors: Mullaji AB, Shetty GM, Kanna R, Vadapalli RC
Abstract
We prospectively studied variations in valgus correction angle (VCA) and the influence of preoperative limb deformity on VCA in 503 consecutive total knee arthroplasties done in 393 patients. The percentage of limbs that had VCA values less than 5° was 10.9%, and that with VCA values greater than 7° was 44.9%. The percentage of limbs with VCA greater than 7° was significantly more in varus knees, and that with VCA less than 5° was significantly more in valgus knees; preoperative deformity showed a significant correlation with VCA. Choosing a fixed-routine VCA of 5° to 7° may cause an unacceptable planning error that may be minimized by individualizing VCA or using computer navigation.
PMID: 22677145 [PubMed - indexed for MEDLINE]
Abrasive wear and metallosis associated with cross-linked polyethylene in total hip arthroplasty.
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Abrasive wear and metallosis associated with cross-linked polyethylene in total hip arthroplasty.
J Arthroplasty. 2013 Jan;28(1):197.e17-21
Authors: O'Brien ST, Burnell CD, Hedden DR, Brandt JM
Abstract
A 34-year-old female patient received a cobalt-chromium (CoCr) alloy femoral head on cross-linked polyethylene total hip replacement for the revision of her fractured ceramic-on-ceramic total hip replacement. The CoCr alloy femoral head became severely worn due to third-body abrasive wear by ceramic particles that could not be removed by synovectomy or irrigation at revision surgery. Ceramic particles were found embedded in the cross-linked polyethylene liner. The CoCr alloy femoral head exhibited a total mass loss of 14.2 g and the generated wear particles triggered metallosis in the patient. The present case study suggests not revising a fractured ceramic-on-ceramic total hip replacement with a CoCr alloy femoral head and a cross-linked polyethylene liner to avoid metallosis due to third-body abrasive wear.
PMID: 22770854 [PubMed - indexed for MEDLINE]
[Treatment of infected total knee arthroplasty with a self-made, antibiotic-loaded cement articulating spacer].
[Treatment of infected total knee arthroplasty with a self-made, antibiotic-loaded cement articulating spacer].
Zhongguo Gu Shang. 2013 Feb;26(2):119-23
Authors: Zhang Q, Zhou YG, Chen JY, Liu M, Zhang GQ, Chai W, Fu YM, Wang XL, Dong XY, Wang Y
Abstract
OBJECTIVE: To study the efficacy of self-made, antibiotic-loaded cement articulating spacer in the treatment of infected total knee arthroplasty.
METHODS: The self-made molds were used to form the spacer during the operation. From March 2002 to March 2007, 22 patients with infected knee arthroplasty (10 males with 10 knees, 12 females with 12 knees) were treated with this kind of spacer in our center. The mean age of the patients was 59.6 years old (33 to 75 years old). The interval time between primary arthroplasty and first onset of infective syndrome was 6.7 months (1 to 14 months). The diagnosis was established by the clinical presentation,serum laboratory inflammatory markers (white blood cell count,erythrocyte sedimentation rate and C-reactive protein) and knee aspiration. The serum laboratory inflammatory markers were used to measure the systemic response to infection. Clinical and radiographic follow-up was regularly performed by HSS score system and X-ray.
RESULTS: All the patients were followed, the average interval between debridement and reimplantation was 4.7 months (3 to 9 months) and the infection control rate was 100% after the implantation of spacer. The average follow-up duration after reimplantation was 29.8 months (10 to 64 months) and there was no recurrence of infection at the latest follow-up. The HSS score increased from 40.5+/-5.9 to 65.8+/-7.5 after the implantation of spacer, furthermore, the score reached 88.7+/-5.1 in average at the latest follow-up. The patient satisfaction rate was 95.3%.
CONCLUSION: This self-made molds and spacers is a reliable approach for the management of infected knee arthroplasty with some virtues, such as providing a mobile and functional joint through the treatment course, decreasing the difficulty of reimplantation, avoiding of a long-term post-operative infusion and high effective for eradicating infection.
PMID: 23678757 [PubMed - in process]
Is the Pie-Crusting Technique Safe for MCL Release in Varus Deformity Correction in Total Knee Arthroplasty?
Is the Pie-Crusting Technique Safe for MCL Release in Varus Deformity Correction in Total Knee Arthroplasty?
J Arthroplasty. 2013 May 13;
Authors: Meneghini RM, Daluga AT, Sturgis LA, Lieberman JR
Abstract
Established for lateral release in TKA, the pie-crusting technique has not been studied for the medial collateral ligament (MCL). In cadaveric knees the MCL was release with a pie-crusting technique in one and traditional technique in the contralateral knee. Along with a control group, each MCL was subjected to mechanical testing. The stiffness, force and stress required to cause ligament elongation were less in the pie-crusting group (p < 0.05) compared to the control group, but were not statistically different than the traditional group. The pie-crusting group demonstrated a characteristic "stair-step" failure mode at the joint line, whereas the traditional group failed elastically at the tibial insertion. MCL pie-crusting is likely technique dependent since failure occurs within the ligament itself and further study is warranted.
PMID: 23680500 [PubMed - as supplied by publisher]
Quantitative computed tomography assessment of bone mineral density after 2 years’ oral bisphosphonate treatment in postmenopausal osteoarthritis patients who underwent total knee arthroplasty.
Quantitative computed tomography assessment of bone mineral density after 2 years' oral bisphosphonate treatment in postmenopausal osteoarthritis patients who underwent total knee arthroplasty.
J Int Med Res. 2013 May 16;
Authors: Lee JK, Choi CH, Kang CN
Abstract
OBJECTIVES: To identify the effects of two years' oral bisphosphonate (alendronate) treatment in patients who underwent total knee arthroplasty (TKA); to determine whether significant responses seen after the first year of treatment changed during the second year. Additionally, the study tried to identify factors relating to bone mineral density (BMD) changes. METHODS: This was a prospective 2-year follow-up study of a previous 1-year report of postmenopausal women with knee osteoarthritis who underwent primary unilateral or staged bilateral TKA, after which they received 70?mg alendronate orally once-weekly. BMD was measured using quantitative computed tomography (QCT) on lumbar vertebrae at baseline (pre-TKA) and at 12 and 24 months. Factors associated with BMD changes were determined by regression analysis. RESULTS: Sixty-one patients entered the second year and continued treatment for ?24 months. Mean vertebral QCT BMDs at baseline and after 12 and 24 months' alendronate treatment were 71.8?mg/ml (41.9-97.5?mg/ml), 69.3?mg/ml (31.4-103.9?mg/ml), and 72.7?mg/ml (33.1-136.1?mg/ml), respectively. Patients undergoing bilateral TKA and who had more severe OA at baseline (bilateral severe [grade 4] OA) had a lower BMD response after 2 years' bisphosphonate treatment, compared with patients with less severe unilateral knee OA who underwent unilateral TKA. Improvements were, however, seen compared with year 1 levels. Low BMI was associated with BMD nonresponse. CONCLUSIONS: Patients with bilateral severe OA (grade 4) requiring bilateral knee replacement are at greater risk of nonresponse after 2 years' oral alendronate treatment. A longer duration of treatment may be necessary in these patients.
PMID: 23680667 [PubMed - as supplied by publisher]
Autologous bone plugs in unilateral total knee arthroplasty.
Autologous bone plugs in unilateral total knee arthroplasty.
Indian J Orthop. 2013 Mar;47(2):182-7
Authors: Protzman NM, Buck NJ, Weiss CB
Abstract
BACKGROUND: The purpose of this study was to compare blood loss, declines in hemoglobin (HgB) and hematocrit (HcT) levels, and required homologous transfusions for patients who either had the femoral intramedullary defect left open or filled with an autologous bone plug during total knee arthroplasty (TKA). We hereby present our results of autologous bone plugs in unilateral TKA.
MATERIALS AND METHODS: A retrospective chart review was performed on 55 patients diagnosed with osteoarthritis (OA) who had undergone unilateral TKA. Twenty six patients had the femoral defect filled with an autologous bone plug and 29 did not. Lateral releases and patella replacements were not performed. Drained blood was reinfused when appropriate.
RESULTS: MEAN BLOOD LOSS AND MEAN BLOOD REINFUSED WERE SIMILAR FOR THE PLUGGED (LOSS: 960.8 ± 417.3 ml; reinfused: 466.7 ± 435.9 mL) and unplugged groups (loss: 1065.9 ± 633.5 ml, P = 0.38; reinfused: 528.4 ± 464.8 ml, P = 0.61). Preoperative HgB (14.3 ± 1.4 g/dL, P = 0.93) and HcT levels (42.2 ± 4.6%, P = 0.85) were similar across plug conditions. HgB and HcT levels declined similarly for the plugged (2.7 ± 1.2 g/dl and 7.9 ± 4.0%) and unplugged groups (3.0 ± 0.9 g/dl, P = 0.16 and 9.0 ± 2.6%, P = 0.16), respectively. Of patients, one in the plugged group and none in the unplugged group required homologous transfusions (P = 0.5).
CONCLUSION: The autologous bone plug does not appear to reduce the need for homologous blood transfusions following unilateral TKA.
PMID: 23682181 [PubMed - in process]
Early, intensified home-based exercise after total hip replacement–a pilot study.
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Early, intensified home-based exercise after total hip replacement--a pilot study.
Physiother Res Int. 2012 Dec;17(4):214-26
Authors: Mikkelsen LR, Mikkelsen SS, Christensen FB
Abstract
BACKGROUND AND PURPOSE: Despite a successful surgical procedure, deficits in muscle strength and physical function are documented 1-2?years after total hip replacement (THR). There is a lack of evidence concerning which rehabilitation strategy is the most effective after THR. The purpose of this pilot study was to investigate the feasibility of an early-initiated intensified, home-based training regime and to form the basis of future studies with regard to exercises, outcome measures and power calculations.
METHODS: The trial is a single-blinded, cluster-randomized controlled trial performed at an orthopaedic physiotherapy department in a public hospital in Denmark. A consecutive sample of 46 patients undergoing primary THR surgery for osteoarthritis between September 2008 and January 2009 was included. Forty-four patients completed the trial (96% follow-up). Participants were randomly assigned to an intervention group (IG, n?=?23) receiving 12?weeks of intensified exercises (e.g. rubber band resistance) or a control group (CG, n?=?21) receiving standard rehabilitation exercises without external resistance. The outcome measurements were maximal gait speed, isometric hip abductor muscle strength, one-legged stance, health-related quality of life (EuroQol-5 Dimensions), patient satisfaction, and patient-evaluated function, stiffness and pain (Western and Ontario McMasters University Osteoarthritis Index).
RESULTS: There were significant increases in both groups in all the measurements during the 12?weeks of exercises. All participants in the IG were satisfied or very satisfied with the exercises compared with 85% in the CG (P?=?0.095). In the IG, four participants (17.4%) had difficulties when performing the intensified exercises at home. Hip abduction strength was significantly weaker in the leg operated compared with the leg not operated on after the intervention in both groups (P?<?0.01).
CONCLUSION: This pilot study indicates that the majority of THR patients tolerated early-initiated intensified exercises without additional pain and with high patient satisfaction. It seems that some of the patients need supervision to perform intensified exercises.
PMID: 22451440 [PubMed - indexed for MEDLINE]
Predictors of femoral neck fracture following hip resurfacing: a cadaveric study.
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Predictors of femoral neck fracture following hip resurfacing: a cadaveric study.
J Arthroplasty. 2013 Jan;28(1):110-6
Authors: Davis ET, Olsen M, Zdero R, Smith GM, Waddell JP, Schemitsch EH
Abstract
We aimed to establish if radiological parameters, dual energy x-ray absorptiometry (DEXA) and quantitative CT (qCT) could predict the risk of sustaining a femoral neck fracture following hip resurfacing. Twenty-one unilateral fresh frozen femurs were used. Each femur had a plain digital anteroposterior radiograph, DEXA scan and qCT scan. Femurs were then prepared for a Birmingham Hip Resurfacing femoral component and loaded to failure. Results demonstrated that gender and qCT measurements showed strong correlation with failure load. QCT could be used as an individual measure to predict risk of post-operative femoral neck fracture. However, when qCT is unavailable; gender, pre-operative DEXA scan and Neck Width measurements can be used together to assess risk of post-operative femoral neck fracture in patients due to undergo hip resurfacing.
PMID: 22770857 [PubMed - indexed for MEDLINE]
Metal ion levels not sufficient as a screening measure for adverse reactions in metal-on-metal hip arthroplasties.
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Metal ion levels not sufficient as a screening measure for adverse reactions in metal-on-metal hip arthroplasties.
J Arthroplasty. 2013 Jan;28(1):78-83
Authors: Macnair RD, Wynn-Jones H, Wimhurst JA, Toms A, Cahir J
Abstract
This study aims to assess the accuracy of metal ion analysis in the diagnosis of adverse reaction to metal debris (ARMD) in patients with metal-on-metal hip arthroplasties by comparing the cobalt and chromium levels in 57 patients (62 hips) to findings on metal artifact reduction magnetic resonance imaging (MRI). An ARMD was detected using MRI in 18 (29%) of the hips. Forty patients had cobalt levels less than 7 ?g/L, and 33 had chromium levels less than 7 ?g/L, but 8 of these had an ARMD on MRI and only minimal symptoms (Oxford Hip Score ? 44/48). The incidence of ARMD was significantly higher when chromium concentration was above 7 ?g/L (P = .02), but normal metal ion levels can be misleading and metal artifact reduction MRI imaging is advised in all patients.
PMID: 22771092 [PubMed - indexed for MEDLINE]
Excellent fixation achieved with cementless posteriorly stabilized total knee arthroplasty.
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Excellent fixation achieved with cementless posteriorly stabilized total knee arthroplasty.
J Arthroplasty. 2013 Jan;28(1):7-13
Authors: Harwin SF, Kester MA, Malkani AL, Manley MT
Abstract
Cementless posteriorly stabilized (PS) total knee arthroplasty has not been widely accepted primarily because of prior unpredictable results and concern about micromotion at the tibial fixation interface caused by the cam/post interaction. A prospective consecutive series of 114 cementless, tricompartmental periapatite-coated single-radius PS implants in 110 patients with a mean age 62 years was performed to determine if initial stability and biologic fixation could be achieved. At a mean follow-up of 36 months, all implants demonstrated radiographic evidence of stable biologic fixation with no evidence of loosening, osteolysis, stress shielding, or progressive radiolucent lines. Based on these early results, cementless, periapatite-coated single-radius PS total knee arthroplasty offers marked promise.
PMID: 22854342 [PubMed - indexed for MEDLINE]
D5 Creation