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41.
BackgroundAssessing patients’ functional outcomes following total knee arthroplasty (TKA) with traditional scoring systems is limited by their ceiling effects. Patient’s Joint Perception (PJP) question of the reconstructed joint is also of significant interest. Forgotten Joint Score (FJS) was created as a more discriminating option. The actual score constituting a “forgotten joint” has not yet been defined. The primary objective of this study is to compare the PJP and the FJS in TKA patients to determine the FJS score that corresponds to the patient’s perception of a natural joint.MethodsOne hundred TKAs were assessed at a mean of 40.6 months of follow-up using the PJP question, FJS, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Correlation between the 3 scores and their ceiling effects were analyzed.ResultsWith PJP question, 39% of the patients perceived a natural joint (FJS: 92.9; 95% confidence interval [CI], 89.4-96.4), 12% an artificial joint with no restriction (FJS: 79.5; 95% CI, 65.7-93.3), 36% an artificial joint with minor restrictions (FJS: 70.0; 95% CI, 63.2-76.9), and 13% had major restrictions (FJS: 47.3; 95% CI. 32.8-61.7). PJP has a high correlation with FJS and WOMAC (Spearman’s rho, −0.705 and −0.680, respectively). FJS and WOMAC had a significant ceiling effect with both reaching the best possible score in >15%.ConclusionPatients perceiving their TKA as a natural knee based on PJP have a FJS ≥89. PJP has a good correlation with FJS and may be a shorter, simple, and acceptable alternative.  相似文献   
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Objectives

Short successive periods of skeletal muscle disuse have been suggested to substantially contribute to the observed loss of skeletal muscle mass over the life span. Hospitalization of older individuals due to acute illness, injury, or major surgery generally results in a mean hospital stay of 5 to 7 days, during which the level of physical activity is strongly reduced. We hypothesized that hospitalization following elective total hip arthroplasty is accompanied by substantial leg muscle atrophy in older men and women.

Design and participants

Twenty-six older patients (75 ± 1 years) undergoing elective total hip arthroplasty participated in this observational study.

Measurements

On hospital admission and on the day of discharge, computed tomographic (CT) scans were performed to assess muscle cross-sectional area (CSA) of both legs. During surgery and on the day of hospital discharge, a skeletal muscle biopsy was taken from the m. vastus lateralis of the operated leg to assess muscle fiber type–specific CSA.

Results

An average of 5.6 ± 0.3 days of hospitalization resulted in a significant decline in quadriceps (?3.4% ± 1.0%) and thigh muscle CSA (?4.2% ± 1.1%) in the nonoperated leg (P < .05). Edema resulted in a 10.3% ± 1.7% increase in leg CSA in the operated leg (P < .05). At hospital admission, muscle fiber CSA was smaller in the type II vs type I fibers (3326 ± 253 μm2 vs 4075 ± 279 μm2, respectively; P < .05). During hospitalization, type I and II muscle fiber CSA tended to increase, likely due to edema in the operated leg (P = .10).

Conclusions

Six days of hospitalization following elective total hip arthroplasty leads to substantial leg muscle atrophy in older patients. Effective intervention strategies are warranted to prevent the loss of muscle mass induced by short periods of muscle disuse during hospitalization.  相似文献   
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《The Journal of arthroplasty》2020,35(8):2200-2203
BackgroundRecently, a revised definition of the minor criteria scoring system for diagnosing periprosthetic joint infection (PJI) was developed by the second International Consensus Meeting on musculoskeletal infection. The new system combines preoperative and intraoperative findings, reportedly achieving high sensitivity and specificity. We aimed to validate the modified scoring system at a high-volume center.MethodsWe retrospectively reviewed patients who underwent a revision total hip or knee arthroplasty at our institution from May 2015 to August 2018. Serum C-reactive protein, synovial white blood cell count and polymorphonuclear percentage, leukocyte esterase test, alpha-defensin, microbiological and histologic results, and documented existence of sinus tract and intraoperative purulence were available for all patients. Cases with at least 1 major criterion were considered as infected. Using the new minor criteria, a score of ≥6 reflects PJI, while a score <3 can be considered as noninfected. Sensitivity, specificity, mean accuracy (ACC), positive predictive value (PPV), and negative predictive value (NPV) were analyzed.ResultsA total of 345 cases were included. A cutoff score of ≥6 points had the following diagnostic performance: area under the curve (AUC) = 0.90; ACC = 0.88; sensitivity = 0.96; specificity = 0.84; PPV = 0.70; NPV = 0.98. Diagnostic performance was better for the hip (AUC = 0.92; ACC = 0.90; sensitivity = 0.96; specificity = 0.86; PPV = 0.81; NPV = 0.98) than the knee (AUC = 0.89; ACC = 0.85; sensitivity = 0.95; specificity = 0.83; PPV = 0.59; NPV = 0.98).ConclusionThe modified scoring system proposed by the 2018 International Consensus Meeting in diagnosing PJI showed high sensitivity and a good performance, especially as rule-out diagnostic criteria. The cutoff level seems to be different between the hip and knee. Further validation studies considering the acknowledged limitations are recommended.  相似文献   
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PurposeAttempts by magnetic resonance (MR) manufacturers to help imaging centres improve patient throughput has led to the development of more automated acquisition. This software is capable of customizing individual scan alignment; potentially improving imaging efficiency and standardizing protocols. However, substantial investments are required to introduce such systems, potentially deterring their widespread application. This study assessed the implementation costs and reduction in examination durations for automated knee MR imaging (MRI) software.Materials and MethodsResearch activities were performed at a community-based academic centre on a 3-Tesla (3-T) system using Siemens' Day Optimizing Throughput (Dot) knee software. Examination acquisition times were extracted from the system before and after software implementation. Fiscal year 2012/13 finances were used to determine the average hourly cost of MRI utilization. Costs associated with automated software implementation were also calculated. Finally, the number of knee scans required to achieve a positive return on investment using the software was established.Results and DiscussionThe mean (standard deviation, sample size) pre- and post-Dot software scan times were 23.20 (4.18, n = 266) and 21.94 (4.51, n = 59) minutes, respectively, for a routine knee scan and 11.88 (1.60, n = 74) and 11.24 (1.51, n = 27) minutes, respectively, for a fast knee scan. The overall weighted average resulted in a 64-second time savings per automated knee examination. This negligible time savings would be extremely difficult to make use of clinically. Dot simplified 29 unique knee protocols to two, improving the consistency of knee examinations. Current Dot software is not compatible with all patients and therefore has limitations that are a concern among MR technologists.ConclusionAdoption of automated knee systems could assist in standardizing protocols; however, the cost of implementation and difficulty in modifying patient scheduling to reflect the minimal time savings would make a financial return unlikely to occur at small- and medium-sized institutions.  相似文献   
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《The Journal of arthroplasty》2022,37(7):1338-1347
BackgroundMultimodal pain therapy combining analgesics, local infiltration analgesia (LIA) and peripheral nerve blocks, such as fascia iliaca compartment block (FICB), can improve postoperative pain, nausea and vomiting (PONV) and ambulation in patients undergoing total hip arthroplasty (THA). We hypothesized that addition of FICB would decrease opioid requirements and length of stay (LOS) but could create a motor block.MethodsThis is a single center, prospective, blinded randomized controlled study of 152 patients undergoing elective THA via direct anterior approach from October 2019 till August 2021. Three patient groups were defined: patients receiving only spinal anesthesia (control group, n = 53); spinal anesthesia with LIA perioperatively (n = 50); and spinal anesthesia with FICB on the recovery unit (n = 49). Outcome measures consisted of postoperative pain scores, PONV, length of hospital stay, opioid requirements and mobility.ResultsOverall pain scores were low for all patient groups, with a lower pain score for LIA in comparison to the control group until 4 hours postoperatively (P < .05). Length of hospital stay, postoperative pain, nausea and vomiting (PONV) scores and quadriceps muscle strength did not differ significantly between groups. The control group showed higher scores at 12 hours postoperatively in comparison to FICB regarding rehabilitation potential, use of walking aids and activities of daily living (P < .05), but all groups reached the same endpoint 48 hours postoperatively. The LIA and FICB groups required less opioids until 24 hours postoperatively.ConclusionLIA is a beneficial adjuvant therapy to spinal anesthesia in THA patients as it may decrease pain scores and the need for opioid consumption. Adjuvant FICB only provided lower opioid requirements.  相似文献   
48.
BackgroundConsiderable practice variability exists among orthopedic surgeons performing total knee arthroplasty (TKA). The purpose of this study is to understand what TKA surgical and perioperative techniques are standard among high-volume academic knee arthroplasty surgeons.MethodsA written survey with 59 questions regarding management preferences in TKA was distributed by the 2018 John N. Insall Traveling Fellows to all arthroplasty-trained attending physicians at 13 medical centers, with 45 responses recorded.ResultsSurveyed surgeons performed unicompartmental knee arthroplasty (88%) and bilateral TKA (87%). Most surveyed surgeons rarely or never performed outpatient primary TKA (71%). Conventional alignment guides and cemented implants were used by 80% of respondents. Most surgeons used posterior-stabilized implants (67%), followed by cruciate-retaining (20%), ultracongruent (20%), and medial congruent or medial pivot designs (17.8%). Surveyed surgeons frequently or always resurfaced the patella (73%), used a tourniquet for the entire case (73%), and used tranexamic acid for all TKAs (91%). The most common locations for intra-articular anesthetic injection were the arthrotomy (91%), the periosteum (84%), and the medial posterior capsule (82%). Saline (62%) and dilute iodine (47%) were the most common irrigation fluids. The arthrotomy was most commonly closed with running barbed suture (60%) followed by interrupted vicryl (40%). Skin closure was predominantly with running monocryl (60%) followed by staples (29%). Anticoagulation for TKA was primarily aspirin 81 mg BID (60%).ConclusionThere was considerable variability among surgeons polled although a strong preference for more conventional and less developmental techniques prevailed.  相似文献   
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