[Show abstract][Hide abstract] ABSTRACT: A systematic review appraising the clinical performance and safety of the primary SIGMA modular knee system (DePuy-Synthes, Warsaw, Ind.) found 5 registry reports and 53 journal publications reporting survivorship or postoperative increase in Knee Society scores on 241632 primary SIGMA knee arthroplasties. Pooled data from national joint registries and clinical studies on primary SIGMA knee survivorship were comparable. Both were higher than for all other knees in 5 national joint registries up to 5 years. Compared with pooled data from 2 independent systematic reviews of primary non-SIGMA knees, the SIGMA system provided comparable postoperative changes in Knee Society knee score and a nonsignificant trend of higher postoperative changes in Knee Society function score. This finding suggests that this knee system provides excellent durable results.
The Journal of arthroplasty 01/2014; 29(7). DOI:10.1016/j.arth.2014.01.012 · 2.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Patient specific instrumentation (PSI) was developed to increase total knee arthroplasty (TKA) accuracy and efficiency. The study purpose was to compare immediate post-operative mechanical alignment, achieved using PSI, with conventional and computer assisted surgery (CAS) instruments in high volume TKA practices. This prospective, multicenter, non-randomized study accrued 66 TKA patients using PSI. A computed tomography (CT) based algorithm was used to develop the surgical plan. Sixty-two percent were females, 99% were diagnosed with osteoarthritis, average age at surgery was 66years, and 33 was the average body mass index. A historical control group was utilized that underwent TKA using conventional instruments (n=86) or CAS (n=81), by the same set of surgeons. Postoperative mechanical alignment was comparable across the groups. Operative time mean and variance were significant.
The Journal of arthroplasty 08/2013; 29(2). DOI:10.1016/j.arth.2013.06.029 · 2.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Despite technical improvements, revision rates for total knee arthroplasties (TKAs) remain high. Our goal was to report the reason(s) for revision TKA in a large, current, multicenter series and compare those reasons with previously published reasons. We retrospectively identified 820 consecutive revision TKAs (693 patients, 2000-2012) from our 3 centers and recorded the primary reason for the revision. The top seven reasons for the revision were aseptic loosening (23.1%), infection (18.4%), polyethylene wear (18.1%), instability (17.7%), pain/stiffness (9.3%), osteolysis (4.5%), and malposition/malalignment (2.9%). Comparison with previously published reasons showed fewer TKA revisions for polyethylene wear, osteolysis, instability, and malalignment. These changes may represent improvements in surgical technique and implants.
The Journal of arthroplasty 07/2013; 28(8). DOI:10.1016/j.arth.2013.04.051 · 2.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In recent years, metal-on-metal (MOM) arthroplasty has come under fire with reported adverse outcomes of metal hypersensitivity, adverse local tissue reaction (ALTR), and the carcinogenicity concern from systemic metal ions. We present a retrospective analysis of 354 primary total hip arthroplasties from 2 independent centers. Revision data, predicted survival and Harris Hip Scores (HHS) are reported. Nine hips (2.5%) underwent component revision, and 9year predicted survival was 95.8%. One revision had elevated metal ions but no histological evidence of ALTR. Average HHS at a minimum 5year follow up (range 5-10years) improved significantly from 52 pre-operatively to 93 post-operatively. While a 2.5% revision rate and improved clinical outcomes are reported in this study, longer term follow-up is warranted to monitor for late complications.
The Journal of arthroplasty 05/2013; 28(7). DOI:10.1016/j.arth.2013.03.012 · 2.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Pain control is necessary for successful rehabilitation and outcome after total knee arthroplasty. Our goal was to compare the clinical efficacy of periarticular injections consisting of a long-acting local anesthetic (ropivacaine) and epinephrine with and without combinations of an α2-adrenergic agonist (clonidine) and/or a nonsteroidal anti-inflammatory agent (ketorolac). In a double-blinded controlled study, we randomized 160 patients undergoing total knee arthroplasty to receive 1 of 4 intraoperative periarticular injections: Group A, ropivacaine, epinephrine, ketorolac, and clonidine; Group B, ropivacaine, epinephrine, and ketorolac; Group C, ropivacaine, epinephrine, and clonidine; Group D (control), ropivacaine and epinephrine. Compared with Group D, Group A and B patients had significantly lower postoperative visual analog pain scores and nurse pain assessment and Group C patients had a significantly greater reduction in physical therapist pain assessment. We found no differences in other parameters analyzed.
The Journal of arthroplasty 04/2013; 28(8). DOI:10.1016/j.arth.2013.03.008 · 2.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: The Total Knee Arthroplasty (TKA) Complications Workgroup of the Knee Society developed a standardized list and definitions of complications associated with TKA. Twenty-two complications and adverse events believed important for reporting outcomes of TKA were identified. The Editorial Board of Clinical Orthopaedics and Related Research (®), the Executive Board of the Knee Society, and the members of the Knee Society TKA Complications Workgroup came to the conclusion that reporting of a list of TKA adverse events and complications would be more valuable if they were stratified using a validated classification system. QUESTIONS/PURPOSES: The purpose of this article was to stratify the previously published standardized list of TKA adverse events and complications. METHODS: A modified version of the Sink adaptation of the Clavien-Dindo Surgical Complication Classification was applied to the list of standardized TKA complications and adverse events. RESULTS: The proposed stratified classifications of TKA complications were reviewed and endorsed by the Knee Society. CONCLUSIONS: Stratification of TKA complications will allow more in-depth and detailed outcome reporting for surgeons, hospitals, third-party payers, government agencies, joint replacement registries, and orthopaedic researchers. This improvement in reporting of TKA complications will also improve the quality of orthopaedic literature.
Clinical Orthopaedics and Related Research 04/2013; 472(1). DOI:10.1007/s11999-013-2980-0 · 2.77 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
Tranexamic acid (TXA) is an antifibrinolytic that reduces blood loss and transfusion rates in total joint arthroplasty. Blood loss and allogenic transfusion rates have not been well studied in patients receiving TXA and undergoing bilateral staged total knee arthroplasty (TKA). The purpose was to evaluate the effect of TXA on blood loss, hemoglobin (Hb) changes, and transfusion in patients undergoing staged bilateral TKA. Study Design and Methods
The authors compared 51 patients undergoing staged bilateral TKA who received TXA (2g; subjects) with 70 who did not (controls). There were no significant differences between the groups in terms of demographics or preoperative Hb. For each TKA, 1g of TXA was administered intravenously 15 minutes before incision and 1g was administered intravenously at tourniquet release. Blood loss, Hb levels, and transfusions were recorded. Statistical analyses were performed using computer software. Significance was set at 0.05. ResultsSubjects had a significantly lower (p<0.001) mean (SD) blood loss (373.8 +/- 264.6mL vs. 871.6 +/- 457.7mL), significantly higher (p<0.005) Hb levels on Postoperative Days 1 and 2, and a significantly lower (p<0.001) mean (+/- SD) number of transfused allogenic blood units (0.60 +/- 0.84 units vs. 1.53 +/- 1.30 units). ConclusionsTXA reduces blood loss, improves postoperative Hb, and decreases the allogenic blood transfusion requirements for patients undergoing bilateral staged TKA. TXA is an option for patients choosing bilateral staged TKA to decrease the risks associated with blood transfusion or when autologous blood is not available.
[Show abstract][Hide abstract] ABSTRACT: In middle-aged patients with knee arthritis, surgical treatment options include arthroscopic procedures, osteotomies, and unicompartmental and total knee arthroplasty. Unicompartmental knee osteoarthrosis is particularly challenging and controversial in such patients. From December 2001 through October 2005, we treated 32 consecutive middle-aged patients (46 to 59 years old) with 40 medial unicompartmental knee arthroplasties. Three patients were lost to follow-up, leaving 29 for our study. There were two reoperations: one for loosening at 3 years, and one for disease progression at 5 years. Implant survival was modeled using Kaplan-Meier survival function with observations censored if lost to follow-up. At the 6-year survivorship in this group, the overall implant survival rate was 94.1% (95% CI, 78.3-98.5). Knee Society scores had improved significantly (p < 0.001). There were no other instances of osteolysis or radiographic failure. We concluded that, at mid-term follow-up, unicompartmental knee arthroplasty provided satisfactory results for this challenging population.
The journal of knee surgery 07/2012; 26(2). DOI:10.1055/s-0032-1322599 · 1.44 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Despite the importance of complications in evaluating patient outcomes after TKA, definitions of TKA complications are not standardized. Different investigators report different complications with different definitions when reporting outcomes of TKA. QUESTIONS/PURPOSES: We developed a standardized list and definitions of complications and adverse events associated with TKA. METHODS: In 2009, The Knee Society appointed a TKA Complications Workgroup that surveyed the orthopaedic literature and proposed a list of TKA complications and adverse events with definitions. An expert opinion survey of members of The Knee Society was used to test the applicability and reasonableness of the proposed TKA complications. For each complication, members of The Knee Society were asked "Do you agree with the inclusion of this complication as among the minimum necessary for reporting outcomes of knee arthroplasty?" and "Do you agree with this definition?" RESULTS: One hundred two clinical members (100%) of The Knee Society responded to the survey. All proposed complications and definitions were endorsed by the members, and 678 suggestions were incorporated into the final work product. The 22 TKA complications and adverse events include bleeding, wound complication, thromboembolic disease, neural deficit, vascular injury, medial collateral ligament injury, instability, malalignment, stiffness, deep joint infection, fracture, extensor mechanism disruption, patellofemoral dislocation, tibiofemoral dislocation, bearing surface wear, osteolysis, implant loosening, implant fracture/tibial insert dissociation, reoperation, revision, readmission, and death. CONCLUSIONS: We identified 22 complications and adverse events that we believe are important for reporting outcomes of TKA. Acceptance and utilization of these standardized TKA complications may improve evaluation and reporting of TKA outcomes.
Clinical Orthopaedics and Related Research 07/2012; 471(1). DOI:10.1007/s11999-012-2489-y · 2.77 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Management options for the polyethylene patellar button during a revision total knee arthroplasty (TKA) include retention, revision, or removal of the button without replacement (patelloplasty). Our purpose was to determine the midterm outcome of patients undergoing revision TKA with patelloplasty. We retrospectively reviewed a single surgeon's database for patients undergoing such surgery from May 2001 to June 2005 and identified 33 (34 knees). The 25 patients (26 knees) who had at least 6 years' follow-up formed our study group. We compared preoperative and final follow-up Knee Society Scores and radiographs. Mean Knee Society Scores had increased from 50 (range, 23-88) to 93 (range, 41-100), respectively. No patient required additional surgery. We conclude that, at midterm follow-up, patelloplasty appears to be a satisfactory option in the management of the patella in revision TKA.
The Journal of arthroplasty 06/2012; 27(8 Suppl):91-4. DOI:10.1016/j.arth.2012.04.012 · 2.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Cementless femoral fixation has become widely accepted in modern total hip arthroplasty. Treating patients who have a stovepipe-shaped femur (Dorr type C) with cementless implants has traditionally been challenging. We treated 53 consecutive patients (60 hips) who had type C bone with identical tapered, proximally coated implants and postoperative weight bearing as tolerated. At 6 weeks, all 60 hips had radiographically documented bony integration, and at 1 year, there was no evidence of fracture, subsidence, thigh pain, stress shielding, loose stems, or risk of failure. Of those patients, 40 (43 hips) had midterm follow-up (average, 6 years; range, 4-9 years); the findings were the same. We conclude that modern proximally tapered stems can be used with early weight bearing in patients with type C bone.
The Journal of arthroplasty 02/2012; 27(6):1014-8. DOI:10.1016/j.arth.2011.12.019 · 2.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In the United States, the obese population has increased markedly over the last four decades, and this trend continues. High patient weight places additional stress on TKA components, which may lead to increased polyethylene wear, osteolysis, radiolucencies, and clinical failure. Metal-backed tibial components and all-polyethylene tibial components in the general population have comparable osteolysis and failure, but it is unclear whether these components yield similar osteolysis and failure in obese patients.
We therefore determined the (1) function, (2) occurrence of osteolysis, and (3) complications in a cohort of obese patients receiving all-polyethylene tibial components.
Between September 17, 1996, and December 19, 2002, we implanted all-polyethylene tibial components in 90 obese patients (125 knees); 24 patients (33 knees) died and 13 patients (17 knees) were lost to followup, leaving 53 patients (59%) with 75 knees. All surgeries were cruciate-retaining, tricompartmental TKAs. We evaluated patients with Knee Society Scores and serial radiographs. Minimum followup was 7 years (mean, 10.4 years; range, 7-14 years).
At latest followup, mean Knee Society Score was 92 points. There were five tibial radiolucencies, all less than 1 mm and characterized as nonprogressive. We observed minimal, nonprogressive osteolysis in one knee. One patient required reoperation after a traumatic event. There were no implant-related failures and no implants at risk of failure.
At an average 10-year followup, all-polyethylene tibial components were functioning well in this obese group. These findings confirm the effectiveness of all-polyethylene tibial components in obese patients.
Clinical Orthopaedics and Related Research 07/2011; 470(1):117-24. DOI:10.1007/s11999-011-1964-1 · 2.77 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A total of 208 patients were enrolled in a multicenter, prospective randomized, institutional review board-approved study that compared preoperative surgical plan to postoperative 2-dimensional radiographic alignment measured by a blinded reviewer for primary total knee arthroplasty (TKA) implanted using computer-assisted surgery (CAS) compared with conventional TKA instrumentation. The results demonstrated a statistically significant improvement in the coronal tibial component alignment (P < .03) and failed to demonstrate a statistically significant improvement in the mechanical axis, femoral coronal/sagittal, and tibial sagittal alignment. Knee Society Score knee and function scores and 6-minute walk test were equivalent between the 2 treatment groups at all postoperative intervals. There was a statistically significant increase in the skin-skin time (P < .0001) and the time until first bone cut (P < .0001) for the CAS knees compared with those implanted with conventional instrumentation. The use of CAS in this randomized clinical trial conducted at high-volume centers did not offer a clinically meaningful improvement in postoperative alignment, clinical, functional, or safety outcomes compared with conventional TKA.
The Journal of arthroplasty 06/2011; 26(8):1273-1284.e1. DOI:10.1016/j.arth.2011.04.037 · 2.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Postoperative audible squeaking has been well documented in ceramic-on-ceramic hip prostheses, and several metal-on-metal (MOM) THA designs, specifically those used for large-head resurfacing and MOM polyethylene sandwich designs, and are attributed to different implant- and patient-specific factors. Current literature does not identify the incidence of squeaking in modular MOM THA or possible etiologic factors.
Our purposes were to (1) identify the incidence of squeaking in modular MOM prostheses in THA; (2) determine whether males or females were more likely to have squeaking; and (3) determine whether the incidence of squeaking relates to acetabular inclination angle.
We retrospectively reviewed the patient records and radiographs of 539 patients (542 hips) from three independent centers who underwent a MOM THA between February 2001 and December 2005. Demographic and implant factors were evaluated, including measurement of cup inclination angles. The minimum followup was 36 months (mean, 76 months; range, 36-119 months).
We identified squeaking in eight of the 542 hips (1.5%); five were in women and two were in men (one patient had bilateral squeaking). The time to onset of patient-reported audible squeaking averaged 23 months (range, 6-84 months). Squeaking was more likely to occur in women (six of eight hips). No hips with 45º or less acetabular inclination squeaked (291 hips); eight of 251 hips (3.2%) with inclination angles greater than 45º squeaked. Patients who reported squeaking had higher inclination angles than those who did not report squeaking.
Our observations suggest an increased frequency of squeaking in female patients and in patients with greater inclination angles with this MOM implant design.
Clinical Orthopaedics and Related Research 04/2011; 469(9):2577-82. DOI:10.1007/s11999-011-1900-4 · 2.77 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: After right total knee arthroplasty (TKA), patients are usually eager to return to driving. Previous studies suggest 6 weeks postsurgery is a safe time. However, recent advances in surgical technique, pain management, and rehabilitation have theoretically improved recovery after TKA.
We therefore determined if (1) the timeframe for return to driving, as determined by attainment of preoperative braking levels, would be shorter after contemporary right TKA than that reported previously for a traditional TKA; and (2) gender or age influence recovery of baseline response time.
Brake response times for all 29 patients undergoing right-sided TKA between January 17, 2008, and January 29, 2009, were scheduled to be measured by a trained occupational therapist before surgery and at 4, 6, and 8 weeks after surgery. For each patient, testing was discontinued once the preoperative level was achieved.
All patients returned to baseline braking levels by 4 weeks after surgery. Gender and age did not influence recovery times.
If other requirements for driving are met, surgeons may consider allowing patients treated with contemporary right TKAs to drive 4 weeks after surgery.
Clinical Orthopaedics and Related Research 01/2011; 469(1):82-6. DOI:10.1007/s11999-010-1507-1 · 2.77 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This retrospective study compares the short-term outcomes of small-incision unicompartmental knee arthroplasty (41 patients) with standard total knee arthroplasty (TKA) (50 patients) in 91 consecutive patients older than 70 years. Knee Society Scores and range of motion (ROM) were assessed preoperatively, at 6 weeks and 6 months, and through a minimum of 2 years. Postoperative comparisons included blood loss, transfusions, narcotic consumption, length of hospital stay, and complications. While Knee Scores and ROM were similar preoperatively, both were better in the unicompartmental group at each postoperative time interval. Patients with unicompartmental replacements had a much quicker return of function and discontinuation of pain medication. Blood loss was significantly more for the TKA group, as was the need for blood transfusion. None of the unicompartmental patients required transfusion. Narcotic use and length of hospital stay were also significantly less for the unicompartmental group. The overall rate of postoperative medical and surgical complications was similar for the 2 groups, with 1 major complication in each. Overall, the physiologic impact of unicompartmental knee arthroplasty was much less than TKA in this older patient population and resulted in a faster recovery.
[Show abstract][Hide abstract] ABSTRACT: Proponents of minimally invasive total knee arthroplasty claim that patellar eversion and anterior tibial translation during total knee arthroplasty have a deleterious effect on early patient rehabilitation and the early clinical outcome. Our purpose was to identify differences in knee preference and clinical outcome measures in a series of patients who had undergone bilateral total knee arthroplasty with each knee randomized to one of two different surgical approaches: patellar eversion and anterior tibial translation, or patellar subluxation and no tibial translation.
The knees of forty patients were prospectively randomized to one of two treatment groups, patellar eversion or patellar subluxation, with each patient having one knee treated with each type of approach. Three patients were withdrawn, leaving a final study group of thirty-seven patients. The patients and physical therapists were blinded to the type of treatment. Clinical outcomes, including the Knee Society scores, range of motion, quadriceps strength as tested with a dynamometer, and the patient's preferred knee on the basis of pain, motion, and strength, were collected preoperatively and at six weeks, twelve weeks, and six months postoperatively and were analyzed.
At six weeks after the surgery, there were no significant differences between the two groups with regard to the range of motion, quadriceps strength, or Knee Society scores. With regard to the patient's knee preference at six weeks, the two knees were rated as being the same in terms of pain, whereas a higher percentage preferred the knee treated with eversion in terms of motion (43% compared with 35% who preferred the knee treated with subluxation) and strength (43% compared with 22%). The mean arc of motion in both groups was approximately 113 degrees. At twelve weeks and six months after the surgery, we found no significant differences between the treatment groups in terms of the range of motion, quadriceps strength, or Knee Society scores, and there was no difference with regard to the patient's knee preference.
We found no significant differences between the two treatment groups (patellar eversion and anterior tibial translation compared with patellar subluxation and no tibial translation) at six weeks, twelve weeks, or six months after the surgery. We concluded that patellar eversion and anterior tibial translation appear to have no adverse effects on the range of motion, quadriceps strength, or patient's knee preference during the early postoperative recovery period after total knee arthroplasty.
The Journal of Bone and Joint Surgery 07/2009; 91(6):1339-43. DOI:10.2106/JBJS.H.00435 · 5.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: There are several surgical management options for medial knee arthritis, and it is often difficult to decide whether a unicompartmental knee arthroplasty (UKA) or total knee arthroplasty (TKA) is appropriate. Few studies have compared UKAs and TKAs in the same patient. We identified 23 patients with osteoarthritis who had a TKA on one side and a UKA on the other. The preoperative values of the 2 knees were not statistically different. Strict criteria were used to determine whether a UKA could be performed (functional anterior cruciate ligament, minimal deformity, and minimum changes in other compartments). Preoperative radiographs were reviewed to confirm that the knee undergoing TKA had medial compartment disease only. Knee Society scores, radiographic analysis, and patient preferences were recorded for all patients. Average follow-up was 46 months (range, 7.2-148 months) and 42 months (range, 11.5-59.8 months) for TKA and UKA, respectively. We found little or no difference in outcomes between the 2 procedures, except for an improved range of motion with the UKA compared with the TKA (123 degrees +/-9 degrees vs 119.8 degrees +/-7 degrees, respectively). Knee Society scores improved from 45.9 to 89.7 in UKA and from 42.4 to 90.3 in TKA. Of the 23 patients, 11 expressed no preference between either knee and 12 preferred the unicompartmental knee; no patient preferred the total knee. With appropriate patient selection, UKAs are a successful option for patients with osteoarthritis.