Hypothesis and background The purpose of this study was to compare the accuracy of patient-specific guides for total shoulder arthroplasty (TSA) with traditional instrumentation in arthritic cadaver ...shoulders. We hypothesized that the patient-specific guides would place components more accurately than standard instrumentation. Materials and methods Seventy cadaver shoulders with radiographically confirmed arthritis were randomized in equal groups to 5 surgeons of varying experience levels who were not involved in development of the patient-specific guidance system. Specimens were then randomized to patient-specific guides based off of computed tomography scanning, standard instrumentation, and anatomic TSA or reverse TSA. Variances in version or inclination of more than 10° and more than 4 mm in starting point were considered indications of significant component malposition. Results TSA glenoid components placed with patient-specific guides averaged 5° of deviation from the intended position in version and 3° in inclination; those with standard instrumentation averaged 8° of deviation in version and 7° in inclination. These differences were significant for version ( P = .04) and inclination ( P = .01). Multivariate analysis of variance to compare the overall accuracy for the entire cohort (TSA and reverse TSA) revealed patient-specific guides to be significantly more accurate ( P = .01) for the combined vectors of version and inclination. Patient-specific guides also had fewer instances of significant component malposition than standard instrumentation did. Conclusion Patient-specific targeting guides were more accurate than traditional instrumentation and had fewer instances of component malposition for glenoid component placement in this multi-surgeon cadaver study of arthritic shoulders. Long-term clinical studies are needed to determine if these improvements produce improved functional outcomes.
Abstract The femoral component and proprietary instrumentation of a mobile-bearing unicompartmental knee arthroplasty (UKA) was redesigned with an additional peg for enhanced fixation, 15° of extra ...femoral surface for contact in deep flexion, more rounded profile, better fit into the milled surface, and redesigned intramedullary based instrumentation. To assess the benefit of these changes, we compared postoperative radiographs of 219 single-peg and 186 twin-peg UKAs done in 2008–2011. All surviving knees demonstrated satisfactory position and alignment with no radiolucencies observed. Radiographic analysis showed improved and consistent component positioning with the twin-peg design implanted with updated instrumentation compared with the single-peg. The radiographic benefits of improved implant positioning using the twin-peg component and updated instrumentation are clear and carry tremendous potential. More robust follow-up is imperative.
Abstract Modern indications for medial mobile-bearing unicompartmental knee arthroplasty (UKA) include a normal lateral compartment, minimal patellofemoral disease, and a ligamentously stable knee. ...Radiographs and intraoperative inspection can determine the appropriateness of UKA. Magnetic resonance imaging (MRI) interpretations can over-estimate the degree of knee pathology. This study reports the outcomes of UKA performed despite an abnormal MRI of the lateral compartment, patellofemoral compartment, and/or cruciate ligaments. One thousand consecutive medial UKAs were reviewed, and 33 patients had pre-operative MRI with interpretations of osteoarthritic changes in the lateral compartment, patellofemoral compartment, and/or deficiency of the anterior cruciate ligament (ACL). We compared the postoperative Knee Society pain score, total score, and functional score between the abnormal MRI group (n = 33) and the remaining patients (n = 967). Average follow-up was 43.4 months and 38.3 months for the two groups, respectively. Knee Society pain, total, and functional scores for the abnormal MRI group were 40.8, 88.7, and 78.5 respectively compared with 43.4, 90.6, and 80.0 respectively for the remaining patients. The failure rate was 3% (1/33) in the abnormal MRI group and 4% (39/967) in the remaining patients. Based on the numbers available, there were no differences between the two groups in terms of survival and clinical results. The results of this study suggest abnormal preoperative MRI findings do not have an influence on the outcome of UKA when modern radiographic and clinical criteria are met.
Clinical Results of Patellofemoral Arthroplasty Morris, Michael J., MD; Lombardi, Adolph V., MD, FACS; Berend, Keith R., MD ...
The Journal of arthroplasty,
10/2013, Letnik:
28, Številka:
9
Journal Article
Recenzirano
Abstract Isolated patellofemoral arthritis can be a disabling condition that can be challenging to treat. Patients with symptoms recalcitrant to conservative measures are considered for total or ...partial knee arthroplasty. This retrospective study reports the results of patellofemoral arthroplasty at a single center using a variety of implant designs. Thirty patients (37 knees) with isolated patellofemoral disease treated with patellofemoral arthroplasty with a minimum of one year follow-up were evaluated. The majority of patients were female (83%) and the underlying diagnosis was osteoarthritis in 98% of knees. Reported follow-up averaged 31 months. Average Knee Society Pain, Functional, and Clinical Scores improved from pre-op to most recent follow-up. Two complications (5.4%) required intervention. One patient was converted to a total knee arthroplasty secondary to patella instability.
The purpose of this study is to review the incidence of symptomatic venous thromboembolism (VTE) in patients undergoing outpatient primary total knee arthroplasty (TKA) who used a portable pneumatic ...compression device as part of their VTE prophylaxis protocol.
A retrospective review of all outpatient primary TKA procedures in which patients used ambulatory pneumatic compression pumps as part of their multimodal VTE prophylaxis was performed from 2016 through 2018. This yielded a cohort of 1131 patients (1453 TKAs). An aspirin (ASA)-based protocol was used in patients with standard VTE risk receiving either 81 mg or 325 mg of ASA twice daily for 6 weeks postoperatively. High-risk patients received a stronger chemoprophylaxis for 2 weeks followed by ASA for 4 weeks. Pneumatic compression pumps were worn for 23 hours/day for 14 days.
VTE prophylaxis medication was 81-mg ASA in 56% of patients, 325-mg ASA in 10% of patients, and stronger chemoprophylaxis in 34% of patients. Patients were considered morbidly obese (body mass index >40 kg/m2) in 267 (18.4%) procedures. Ninety-seven (6.7%) patients had a preoperative history of VTE event. Forty-nine duplex ultrasounds were performed (3.3% of TKAs). Confirmed VTE events were documented in only 5 (0.3%) patients. All VTEs occurred in high-risk patients who were discharged on stronger chemoprophylaxis. The time (days) to VTE was 3, 3, 7, 45, and 88 days.
The use of portable pneumatic compression pumps as part of a multimodal VTE prophylaxis protocol aided in a very low rate of symptomatic VTE events in patients undergoing outpatient primary TKA.
Most implants for total knee arthroplasty (TKA) are comprised of alloys that contain nickel. Controversy exists whether metal allergies produce negative effects and affect clinical outcomes. The ...purpose of this study was to retrospectively review a minimum 2-year follow-up with an ion-bombarded titanium TKA implant in patients with reported metal sensitivity.
A retrospective review of patients who underwent primary TKA with the ion-bombarded titanium Vanguard (Zimmer Biomet, Warsaw, IN) implant with 2-year minimum follow-up was performed from 2008 through 2017. The query revealed 346 patients (451 knees) with minimum 2-year follow-up. The mean age was 64.7 years, the mean body mass index was 35.1 kg/m2, and 95% of patients were women.
The mean follow-up was 4.6 years. The mean range of motion improved from 109° to 112° (P = .03), University of California Los Angeles activity scale from 4.1 to 5.1 (P < .001), Knee Society Clinical scores from 36 to 89 (P < .001), and Knee Society Functional scores from 48 to 73 (P < .001). There were 5 (1.1%) revisions: 2 infections (2-staged exchange), 1 tibial revision for aseptic loosening after a fall, and 2 bearing exchanges for instability. Other surgeries were open reduction internal fixation of periprosthetic fracture, 1 arthroscopic release of snapping popliteus, and 4 local wound incision and debridement (2 superficial infections and 2 nonhealing wounds). Manipulation under anesthesia was required in 27 (6%) patients.
These early results are encouraging for the use of alternative metal titanium alloy implants in metal-sensitive patients undergoing primary TKA. At 4.6 years of mean follow-up, patients had substantial improvement in the range of motion and clinical outcomes with a low frequency of revision.
Hypothesis Recent studies have demonstrated better outcomes with operative fixation of displaced midshaft clavicle fractures. We hypothesize that the risk of major complication with intramedullary ...fixation for clavicle fractures will be low. Materials and methods Clavicle fractures in 58 patients were treated with intramedullary fixation. Patients were excluded for concomitant pathologies and prior surgery status. Data collected included age, gender, treatment, fracture location, time of pin removal, type of complication, dates of further surgery, and American Shoulder and Elbow Surgeons (ASES) score. Complications were grouped into major (infection, nonunion, malunion) and minor (skin erosion, painful hardware, hardware breakage without consequence) categories. The mean age at surgery was 38 years (range, 18-67 years). All pins were removed at an average of 67 days (95% confidence interval, 54-85). Results Of the 58 patients, 15 (25.8%) complications occurred in 14 patients (24.1%). Five (8.6%) were classified as major (5 nonunions requiring revision surgery). Ten (17.2%) were classified as minor (1 delayed union, 2 superficial wound infections, 2 hardware failures after union, 5 skin erosions with pin exposure but without significant infection). Postoperative ASES scores average 89 at a mean follow-up of 7 years. Discussion Complete union and function were achieved in most patients, with an 8.6% risk of major complication. Intramedullary fixation has the potential for early but temporary hardware prominence, hardware exposure, and a slightly higher incidence of nonunion. Conclusion Patients with intramedullary fixation can expect smaller scars, no long-term hardware complications, and small potential for refracture or further hardware-related complications after hardware removal.
AbstractPurposeThis study is the first description of hospital-wide anti-infective use according to clinical indication for a pediatric hospital. Children's Hospital Colorado (CHCO) is uniquely ...poised to examine its anti-infective use after the implementation of provider-selected order indications (PSOIs), which are distinct from Diagnosis Related Group classifications in that they are used for clinical treatment as opposed to final diagnosis codes for billing and thus are more granular. MethodsThis study used our institution's mandatory PSOIs to describe overall clinical indications for anti-infective use. For 2016, all anti-infective orders were extracted from the electronic medical record (Epic), including drug name, route, prescribing unit, and PSOI. We calculated the number of times each drug was associated with each indication and the number of times an indication was attributed to each drug, and then analyzed these data in Excel. FindingsThere were 29,258 orders at CHCO in 2016 with at least 1 indication. The most common clinical indication was “prophylaxis–medical/surgical,” accounting for 23% of all orders and commonly associated with cefazolin (42% of prophylaxis–medical/surgical orders). This was followed by the indications of “sepsis/bacteremia” and “pneumonia/sinusitis.” The most commonly prescribed anti-infectives for nonprophylactic clinical indications were IV vancomycin (14%), ceftriaxone (11%), and ampicillin (6%). ImplicationsKnowledge of the clinical reasons for hospital-wide anti-infective use enables hospitals to identify targets for improved use through education and guideline and policy development. This description provides better details than billing codes about the clinical reasons anti-infectives are used and offers a useful template for implementation at other hospitals.
Abstract Unicompartmental knee arthroplasty (UKA) is a less invasive treatment for medial gonarthrosis. However, registry data have demonstrated higher revision and early failure rates. The purpose ...of this study is to report the early survivorship and failure modes in a series of 1000 consecutive medial mobile bearing UKA. UKA patients with a minimum of 2 year follow-up or those meeting the study endpoint (UKA failure or death) were included. Demographic variables, pre and post-operative clinical variables, and mode of failure were analyzed. Eight hundred and thirty-nine knees were included in the analysis. Forty revisions were performed at an average of 23.1 months (range, 2.3–74.2) following UKA for a survivorship of 95.2%. Indications for revision were aseptic loosening (15), tibial collapse (7), mobile bearing dislocation (2), persistent pain (12), progression of disease (2), infection (1), and tibiofemoral instability (1). These results are from a single center and may not be comparable to those of larger reports such as national registries.
Mobile-bearing Unicondylar Knee Arthroplasty Hurst, Jason M., MD; Berend, Keith R., MD
The Orthopedic clinics of North America,
2015, January 2015, 2015-01-00, Letnik:
46, Številka:
1
Journal Article
Recenzirano
With the recent increase in medial unicompartmental arthroplasty, this article reviews the design history, indications, results, and modern technique for the implantation of the Oxford mobile-bearing ...unicompartmental arthroplasty. The article also discusses how the indications for the Oxford differ from the historical indications for medial unicompartmental arthroplasty and supports this paradigm shift with review of the recent data. A detailed series of surgical pearls is also presented to help surgeons with the surgical nuances of the Oxford partial knee.
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