TY - JOUR A1 - Rak, Dominik A1 - Nedopil, Alexander J. A1 - Sayre, Eric C. A1 - Masri, Bassam A. A1 - Rudert, Maximilian T1 - Postoperative inpatient rehabilitation does not increase knee function after primary total knee arthroplasty JF - Journal of Personalized Medicine N2 - Inpatient rehabilitation (IR) is a common postoperative protocol after total knee replacement (TKA). Because IR is expensive and should therefore be justified, this study determined the difference in knee function one year after TKA in patients treated with IR or outpatient rehabilitation, fast-track rehabilitation (FTR) in particular, which also entails a reduced hospital length of stay. A total of 205 patients were included in this multi-center prospective cohort study. Of the patients, 104 had primary TKA at a German university hospital and received IR, while 101 had primary TKA at a Canadian university hospital and received FTR. Patients receiving IR or FTR were matched by pre-operative demographics and knee function. Oxford Knee Score (OKS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and EuroQol visual analogue scale (EQ-VAS) determined knee function one year after surgery. Patients receiving IR had a 2.8-point lower improvement in OKS (p = 0.001), a 6.7-point lower improvement in WOMAC (p = 0.063), and a 12.3-point higher improvement in EQ-VAS (p = 0.281) than patients receiving FTR. IR does not provide long-term benefits to patient recovery after primary uncomplicated TKA under the current rehabilitation regime. KW - total knee arthroplasty KW - fast track rehabilitation KW - inpatient rehabilitation KW - postoperative rehabilitation KW - patient reported outcome measures Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-297322 SN - 2075-4426 VL - 12 IS - 11 ER - TY - JOUR A1 - Sappey-Marinier, Elliot A1 - Howell, Stephen M. A1 - Nedopil, Alexander J. A1 - Hull, Maury L. T1 - The trochlear groove of a femoral component designed for kinematic alignment is lateral to the quadriceps line of force and better laterally covers the anterior femoral resection than a mechanical alignment design JF - Journal of Personalized Medicine N2 - Background: A concern about kinematically aligned (KA) total knee arthroplasty (TKA) is that it relies on femoral components designed for mechanical alignment (MAd-FC) that could affect patellar tracking, in part, because of a trochlear groove orientation that is typically 6° from vertical. KA sets the femoral component coincident to the patient’s pre-arthritic distal and posterior femoral joint lines and restores the Q-angle, which varies widely. Relative to KA and the native knee, aligning the femoral component with MA changes most distal joint lines and Q-angles, and rotates the posterior joint line externally laterally covering the anterior femoral resection. Whether switching from a MAd- to a KAd-FC with a wider trochlear groove orientation of 20.5° from vertical results in radiographic measures known to promote patellar tracking is unknown. The primary aim was to determine whether a KAd-FC sets the trochlear groove lateral to the quadriceps line of force (QLF), better laterally covers the anterior femoral resection, and reduces lateral patella tilt relative to a MAd-FC. The secondary objective was to determine at six weeks whether the KAd-FC resulted in a higher complication rate, less knee extension and flexion, and lower clinical outcomes. Methods: Between April 2019 and July 2022, two surgeons performed sequential bilateral unrestricted caliper-verified KA TKA with manual instruments on thirty-six patients with a KAd- and MAd-FC in opposite knees. An observer measured the angle between a line best-fit to the deepest valley of the trochlea and a line representing the QLF that indicated the patient’s Q-angle. When the trochlear groove was lateral or medial relative to the QLF, the angle is denoted + or −, and the femoral component included or excluded the patient’s Q-angle, respectively. Software measured the lateral undercoverage of the anterior femoral resection on a Computed Tomography (CT) scan, and the patella tilt angle (PTA) on a skyline radiograph. Complications, knee extension and flexion measurements, Oxford Knee Score, KOOS Jr, and Forgotten Joint Score were recorded pre- and post-operatively (at 6 weeks). A paired Student’s T-test determined the difference between the KA TKAs with a KAd-FC and MAd-FC with a significance set at p < 0.05. Results: The final analysis included thirty-five patients. The 20.5° trochlear groove of the KAd-FC was lateral to the QLF in 100% (15 ± 3°) of TKAs, which was greater than the 69% (1 ± 3°) lateral to the QLF with the 6° trochlear groove of the MAd-FC (p < 0.001). The KAd-FC’s 2 ± 1.9 mm lateral undercoverage of the anterior femoral resection was less than the 4.4 ± 1.5 mm for the MAd-FC (p < 0.001). The PTA, complication rate, knee extension and flexion, and clinical outcome measures did not differ between component designs. Conclusions: The KA TKA with a KAd-FC resulted in a trochlear groove lateral to the QLF that included the Q-angle in all patients, and negligible lateral undercoverage of the anterior femoral resection. These newly described radiographic parameters could be helpful when investigating femoral components designed for KA with the intent of promoting patellofemoral kinematics. KW - total knee arthroplasty KW - lateral trochlear undercoverage KW - prosthetic design KW - kinematic alignment KW - patellofemoral relationship Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-290482 SN - 2075-4426 VL - 12 IS - 10 ER - TY - JOUR A1 - Dhaliwal, Anand A1 - Zamora, Tomas A1 - Nedopil, Alexander J. A1 - Howell, Stephen M. A1 - Hull, Maury L. T1 - Six commonly used postoperative radiographic alignment parameters do not predict clinical outcome scores after unrestricted caliper-verified kinematically aligned TKA JF - Journal of Personalized Medicine N2 - Background: Unrestricted caliper-verified kinematically aligned (KA) TKA restores patient’s prearthritic coronal and sagittal alignments, which have a wide range containing outliers that concern the surgeon practicing mechanical alignment (MA). Therefore, knowing which radiographic parameters are associated with dissatisfaction could help a surgeon decide whether to rely on them as criteria for revising an unhappy patient with a primary KA TKA using MA principles. Hence, we determined whether the femoral mechanical angle (FMA), hip–knee–ankle angle (HKAA), tibial mechanical angle (TMA), tibial slope angle (TSA), and the indicators of patellofemoral tracking, including patella tilt angle (PTA) and the lateral undercoverage of the trochlear resection (LUCTR), are associated with clinical outcome scores. Methods: Forty-three patients with a CT scan and skyline radiograph after a KA TKA with PCL retention and medial stabilized design were analyzed. Linear regression determined the strength of the association between the FMA, HKA angle, PTS, PTA, and LUCTR and the forgotten joint score (FJS), Oxford knee score (OKS), and KOOS Jr score obtained at a mean of 23 months. Results: There was no correlation between the FMA (range 2° varus to −10° valgus), HKAA (range 10° varus to −9° valgus), TMA (range 10° varus to −0° valgus), TSA (range 14° posterior to −4° anterior), PTA (range, −10° medial to 14° lateral), and the LUCTR resection (range 2 to 9 mm) and the FJS (median 83), the OKS (median 44), and the KOOS Jr (median 85) (r = 0.000 to 0.079). Conclusions: Surgeons should be cautious about using postoperative FMA, HKAA, TMA, TSA, PTA, and LUCTR values within the present study’s reported ranges to explain success and dissatisfaction after KA TKA. KW - total knee arthroplasty KW - kinematic alignment KW - reoperation KW - revision KW - phenotype Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-288186 SN - 2075-4426 VL - 12 IS - 9 ER - TY - JOUR A1 - Nedopil, Alexander J. A1 - Howell, Stephen M. A1 - Hull, Maury L. T1 - Measurement of tibial orientation helps select the optimal insert thickness to personalize PCL tension in a medial ball-in-socket TKA JF - Journal of Personalized Medicine N2 - As the conformity of a medial ball-in-socket total knee arthroplasty (TKA) provides intrinsic anterior-posterior (A-P) stability, surgeons cannot rely on the manual examination of sagittal laxity to identify the optimal insert thickness. Instead, the present study determined whether measuring tibial axial orientation in extension and 90° flexion with an insert goniometer could identify the optimal thickness that, when implanted, provides high postoperative function. In twenty-two patients that underwent unrestricted caliper-verified kinematic alignment (KA) with a PCL retaining implant, two surgeons measured tibial orientation in extension and 90° flexion with 10, 11, 12, and 13 mm thick insert goniometers. Each TKA had one insert thickness that restored either the maximum external tibial orientation in extension, the maximum internal tibial orientation at 90° flexion, or both relative to 1 mm thinner and thicker inserts. In addition, the 6-month median [interquartile range] Forgotten Joint Score of 73 (54–87) and Oxford Knee Score of 42 (38–45) indicated high satisfaction and function. In conclusion, surgeons using a medial ball-in-socket TKA design can measure external tibial orientation in extension and internal tibial orientation at 90° flexion with an insert goniometer. Furthermore, implanting an insert with the thickness that provided the maximum orientation values resulted in high postoperative function, thereby personalizing PCL tension. KW - posterior cruciate ligament KW - tibial rotation KW - medial pivot KW - total knee arthroplasty KW - kinematic alignment Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-286232 SN - 2075-4426 VL - 12 IS - 9 ER - TY - JOUR A1 - Nedopil, Alexander J. A1 - Howell, Stephen M. A1 - Hull, Maury L. T1 - A TKA insert with a lateral flat articular surface maximizes external and internal tibial orientations without anterior lift-off relative to low- and ultracongruent surfaces JF - Journal of Personalized Medicine N2 - Background: In total knee arthroplasty (TKA), inserts can have different levels of medial and lateral congruency determined by the acuteness of the upslopes of the anterior and posterior articular surfaces. The present study evaluated an insert with different levels of lateral congruency and a medial ball-in-socket congruency to test the hypothesis that a lateral flat (F) insert maximizes external tibial orientation at extension and internal orientation at 90° flexion and lowers the incidence of anterior lift-off relative to low-congruent (LC) and ultracongruent (UC) lateral inserts. Methods: Two surgeons treated 23 patients with unrestricted caliper-verified kinematic alignment (KA) and posterior cruciate ligament (PCL) retention. They randomly trialed inserts with a medial radial dial that functioned as a built-in goniometer by measuring the tibial orientation relative to a sagittal line on the femoral trial component. Anterior lift-off of the insert from the baseplate indicated PCL tightness. Results: The F insert’s mean of 9° of external tibial orientation was higher than that of the LC (5°, p < 0.0001) and UC inserts (2°, p < 0.0001). The −13° of internal tibial orientation at 90° flexion was higher than that of the LC (−9°, p < 0.0001) and UC inserts (−7°, p < 0.0001). The 0% incidence of anterior lift-off was less than that of the LC (26%) and UC inserts (57%) (p < 0.0001). Conclusions: Surgeons and implant manufacturers should know that adding congruency to the lateral articular surface limits external tibial orientation in extension and internal tibial orientation at 90° flexion and overtightens the PCL. These rotational limitations and flexion space tightness can adversely affect patellofemoral tracking and knee flexion. KW - total knee arthroplasty KW - kinematic alignment KW - implant design KW - PCL retention KW - congruency Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-286142 SN - 2075-4426 VL - 12 IS - 8 ER - TY - JOUR A1 - Nedopil, Alexander J. A1 - Dhaliwal, Anand A1 - Howell, Stephen M. A1 - Hull, Maury L. T1 - A surgeon that switched to unrestricted kinematic alignment with manual instruments has a short learning curve and comparable resection accuracy and outcomes to those of an experienced surgeon JF - Journal of Personalized Medicine N2 - After starting an orthopedic practice, a surgeon with a fellowship in mechanically aligned (MA) TKA initiated this study to characterize their learning curve after they switched to unrestricted kinematic alignment (KA) TKA using manual instruments. Accordingly, the present study determined for the inexperienced (IE) surgeon the number of cases required to achieve consistent femoral resections and operating times, and whether the femoral resection accuracy, patient-reported outcome measures (PROMs), and component alignment were different from an experienced (E) surgeon. This prospective cohort study analyzed the IE surgeon's first 30 TKAs, all performed with KA, and 30 consecutive KA TKAs performed by an E surgeon. The resection accuracy or deviation was the calipered thickness of the distal and posterior medial and lateral femoral resections minus the planned resection thickness, which was the thickness of the corresponding condyle of the femoral component, minus 2 mm for cartilage wear, and 1 mm for the kerf of the blade. Independent observers recorded the femoral resection thickness, operative times, PROMs, and alignment. For each femoral resection, the deviation between three groups of patients containing ten consecutive KA TKAs, was either insignificant (p = 0.695 to 1.000) or within the 0.5 mm resolution of the caliper, which indicated no learning curve. More than three groups were needed to determine the learning curve for the operative time; however, the IE surgeon's procedure dropped to 77 min for the last 10 patients, which was 20 min longer than the E surgeon. The resection deviations of the IE and E surgeon were comparable, except for the posterolateral femoral resection, which the IE surgeon under-resected by a mean of −0.8 mm (p < 0.0001). At a mean follow-up of 9 and 17 months, the Forgotten Joint Score, Oxford Knee Score, KOOS, and the alignment of the components and limbs were not different between the IE and E surgeon (p ≥ 0.6994). A surgeon that switches to unrestricted KA with manual instruments can determine their learning curve by computing the deviation of the distal and posterior femoral resections from the planned resection. Based on the present study, an IE surgeon could have resection accuracy, post-operative patient outcomes, and component alignment comparable to an E surgeon. KW - total knee arthroplasty KW - kinematic alignment KW - learning curve KW - accuracy KW - efficiency Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-281842 SN - 2075-4426 VL - 12 IS - 7 ER - TY - JOUR A1 - Steinert, Andre F. A1 - Schröder, Lennart A1 - Sefrin, Lukas A1 - Janßen, Björn A1 - Arnholdt, Jörg A1 - Rudert, Maximilian T1 - The impact of total knee replacement with a customized cruciate-retaining implant design on patient-reported and functional outcomes JF - Journal of Personalized Medicine N2 - Purpose: To treat patients with tricompartimental knee osteoarthritis (OA), a customized cruciate-retaining total knee arthroplasty (CCR-TKA) system can be used, including both individualized instrumentation and implants. The objective of this monocentric cohort study was to analyze patient-reported and functional outcomes in a series of patients implanted with the second generation of this customized implant. Methods: At our arthroplasty center, we prospectively recruited a cohort of patients with tricompartmental gonarthrosis to be treated with total knee replacement (TKA) using a customized cruciate-retaining (CCR) implant design. Inclusion criteria for patients comprised the presence of intact posterior cruciate and collateral ligaments and a knee deformity that was restricted to <15° varus, valgus, or flexion contracture. Patients were assessed for their range of motion (ROM), Knee Society Score (KSS), Western Ontario and McMaster University osteoarthritis index (WOMAC), and short form (SF)-12 physical and mental scores, preoperatively, at 3 and 6 months, as well as at 1, 2, 3, and 5 years of follow-up (FU) postoperatively. Results: The average age of the patient population was 64 years (range: 40–81), the average BMI was 31 (range: 23–42), and in total, 28 female and 45 male patients were included. Implant survivorship was 97.5% (one septic loosening) at an average follow-up of 2.5 years. The KSS knee and function scores improved significantly (p < 0.001) from, respectively, 41 and 53 at the pre-operative visit, to 92 and 86, respectively, at the 5-year post-operative time point. The SF-12 Physical and Mental scores significantly (p < 0.001) improved from the pre-operative values of 28 and 50, to 50 and 53 at the 5-year FU, respectively. Patients experienced significant improvements in their overall knee range of motion, from 106° at the preoperative visit to 122°, on average, 5 years postoperatively. The total WOMAC score significantly (p < 0.001) improved from 49.1 preoperatively to 11.4 postoperatively at 5-year FU. Conclusions: Although there was no comparison to other implants within this study, patients reported high overall satisfaction and improvement in functional outcomes within the first year from surgery, which continued over the following years. These mid-term results are excellent compared with those reported in the current literature. Comparative long-term studies with this device are needed. Level of evidence 3b (individual case–control study). KW - patient-specific KW - custom-made implant KW - total knee arthroplasty KW - TKA KW - knee replacement KW - tricompartmental knee osteoarthritis KW - iTotal Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-312746 SN - 2075-4426 VL - 12 IS - 2 ER - TY - JOUR A1 - Nedopil, Alexander J. A1 - Delman, Connor A1 - Howell, Stephen M. A1 - Hull, Maury L. T1 - Restoring the patient's pre-arthritic posterior slope is the correct target for maximizing internal tibial rotation when implanting a PCL retaining TKA with calipered kinematic alignment JF - Journal of Personalized Medicine N2 - Introduction: The calipered kinematically-aligned (KA) total knee arthroplasty (TKA) strives to restore the patient's individual pre-arthritic (i.e., native) posterior tibial slope when retaining the posterior cruciate ligament (PCL). Deviations from the patient's individual pre-arthritic posterior slope tighten and slacken the PCL in flexion that drives tibial rotation, and such a change might compromise passive internal tibial rotation and coupled patellofemoral kinematics. Methods: Twenty-one patients were treated with a calipered KA TKA and a PCL retaining implant with a medial ball-in-socket and a lateral flat articular insert conformity that mimics the native (i.e., healthy) knee. The slope of the tibial resection was set parallel to the medial joint line by adjusting the plane of an angel wing inserted in the tibial guide. Three trial inserts that matched and deviated 2°> and 2°< from the patient's pre-arthritic slope were 3D printed with goniometric markings. The goniometer measured the orientation of the tibia (i.e., trial insert) relative to the femoral component. Results: There was no difference between the radiographic preoperative and postoperative tibial slope (0.7 ± 3.2°, NS). From extension to 90° flexion, the mean passive internal tibial rotation with the pre-arthritic slope insert of 19° was greater than the 15° for the 2°> slope (p < 0.000), and 15° for the 2°< slope (p < 0.000). Discussion: When performing a calipered KA TKA with PCL retention, the correct target for setting the tibial component is the patient's individual pre-arthritic slope within a tolerance of ±2°, as this target resulted in a 15–19° range of internal tibial rotation that is comparable to the 15–18° range reported for the native knee from extension to 90° flexion. KW - total knee replacement KW - total knee arthroplasty KW - kinematic alignment KW - slope KW - rotation Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-240996 SN - 2075-4426 VL - 11 IS - 6 ER - TY - JOUR A1 - Nedopil, Alexander J. A1 - Shekhar, Adithya A1 - Howell, Stephen M. A1 - Hull, Maury L. T1 - An insert with less than spherical medial conformity causes a loss of passive internal rotation after calipered kinematically aligned TKA JF - Archives of Orthopaedic and Trauma Surgery N2 - Introduction In total knee arthroplasty (TKA), the level of conformity, a medial stabilized (MS) implant, needs to restore native (i.e., healthy) knee kinematics without over-tensioning the flexion space when the surgeon chooses to retain the posterior cruciate ligament (PCL) is unknown. Whether an insert with a medial ball-in-socket conformity and lateral flat surface like the native knee or a less than spherical medial conformity restores higher and closer to native internal tibial rotation without anterior lift-off, an over-tension indicator, when implanted with calipered kinematic alignment (KA), is unknown. Methods and Materials Two surgeons treated 21 patients with calipered KA and a PCL retaining MS implant. Validated verification checks that restore native tibial compartment forces in passive flexion without release of healthy ligaments were used to select the optimal insert thickness. A goniometer etched onto trial inserts with the ball-in-socket and the less than spherical medial conformity measured the tibial rotation relative to the femoral component at extension and 90° and 120° flexion. The surgeon recorded the incidence of anterior lift-off of the insert. Results The insert with the medial ball-in-socket and lateral flat surface restored more internal tibial rotation than the one with less than spherical medial conformity, with mean values of 19° vs. 17° from extension to 90° flexion (p < 0.01), and 23° vs. 20°-120° flexion (p < 0.002), respectively. There was no anterior lift-off of the insert at 90° and 120° flexion. Conclusion An MS insert with a medial ball-in-socket and lateral flat surface that matches the native knee's spherical conformity restores native tibial internal rotation when implanted with calipered KA and PCL retention without over-tensioning the flexion space. KW - calipered KW - medial stabilized KW - spherical KW - conforming KW - insert KW - rotation KW - total knee arthroplasty KW - total knee replacement KW - kinematic alignment Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-266710 SN - 1434-3916 VL - 141 IS - 12 ER - TY - JOUR A1 - Howell, Stephen M. A1 - Gill, Manpreet A1 - Shelton, Trevor J. A1 - Nedopil, Alexander J. T1 - Reoperations are few and confined to the most valgus phenotypes 4 years after unrestricted calipered kinematically aligned TKA JF - Knee Surgery, Sports Traumatology, Arthroscopy N2 - Purpose The present study determined the postoperative phenotypes after unrestricted calipered kinematically aligned (KA) total knee arthroplasty (TKA), whether any phenotypes were associated with reoperation, implant revision, and lower outcome scores at 4 years, and whether the proportion of TKAs within each phenotype was comparable to those of the nonarthritic contralateral limb. Methods From 1117 consecutive primary TKAs treated by one surgeon with unrestricted calipered KA, an observer identified all patients (N = 198) that otherwise had normal paired femora and tibiae on a long-leg CT scanogram. In both legs, the distal femur–mechanical axis angle (FMA), proximal tibia–mechanical axis angle (TMA), and the hip–knee–ankle angle (HKA) were measured. Each alignment angle was assigned to one of Hirschmann’s five FMA, five TMA, and seven HKA phenotype categories. Results Three TKAs (1.5%) underwent reoperation for anterior knee pain or patellofemoral instability in the subgroup of patients with the more valgus phenotypes. There were no implant revisions for component loosening, wear, or tibiofemoral instability. The median Forgotten Joint Score (FJS) was similar between phenotypes. The median Oxford Knee Score (OKS) was similar between the TMA and HKA phenotypes and greatest in the most varus FMA phenotype. The phenotype proportions after calipered KA TKA were comparable to the contralateral leg. Conclusion Unrestricted calipered KA’s restoration of the wide range of phenotypes did not result in implant revision or poor FJS and OKS scores at a mean follow-up of 4 years. The few reoperated patients had a more valgus setting of the prosthetic trochlea than recommended for mechanical alignment. Designing a femoral component specifically for KA that restores patellofemoral kinematics with all phenotypes, especially the more valgus ones, is a strategy for reducing reoperation risk. KW - phenotype KW - total knee arthroplasty KW - total knee replacement KW - kinematic alignment KW - calipered KW - reoperation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-265291 VL - 30 IS - 3 ER - TY - JOUR A1 - Lüdemann, Martin A1 - Jakuscheit, Axel A1 - Ewald, Andrea A1 - Frühmann, Leena A1 - Hölscher-Doht, Stefanie A1 - Rudert, Maximilian A1 - von Hertzberg-Boelch, Sebastian Philipp T1 - Influence of Tranexamic Acid on Elution Characteristics and Compressive Strength of Antibiotic-Loaded PMMA-Bone Cement with Gentamicin JF - Materials N2 - Purpose: The topical application of tranexamic acid (TXA) into the joint space during total joint arthroplasty (TJA) with no increase of complications, has been widely reported. We investigated the influence of TXA on antibiotic release, activity of the released antibiotic against a clinical isolate of S. aureus, and compressive strength of a widely used commercially prepared gentamicin-loaded cement brand (PALACOS R + G). Method: 12 bone cement cylinders (diameter and height = 6 and 12 mm, respectively) were molded. After curing in air for at least 1 h, six of the cylinders were completely immersed in 5 mL of fetal calf serum (FCS) and the other six were completely immersed in a solution consisting of 4.9 mL of FCS and 0.1 mL (10 mg) of TXA. Gentamicin elution tests were performed over 7 d. Four hundred µL of the gentamicin eluate were taken every 24 h for the first 7 d without renewing the immersion fluid. The gentamicin concentration was determined in a clinical analyzer using a homogeny enzyme immuno-assay. The antimicrobial activity of the eluate, obtained after day 7, was tested. An agar diffusion test regime was used with Staphylococcus aureus. Bacteria were grown in a LB medium and plated on LB agar plates to get a bacterial lawn. Fifty µL of each eluate were pipetted on 12-mm diameter filter discs, which were placed in the middle of the agar gel. After 24 h of cultivation at 37 °C, the zone of inhibition (ZOI) for each specimen was measured. The compressive strength of the cements was determined per ISO 5833. Results: At each time point in the gentamicin release test, the difference in gentamicin concentration, obtained from specimens immersed in the FCS solution only and those immersed in the FCS + TXA solution was not significant (p = 0.055–0.522). The same trend was seen in each of the following parameters, after 7 d of immersion: (1) Cumulative gentamicin concentration (p < 0.297); (2) gentamicin activity against S. aureus (strongly visible); (3) ZOI size (mostly > 20 mm) (p = 0.631); and (4) compressive strength (p = 0.262). Conclusions: For the PALACOS R + G specimens, the addition of TXA to FCS does not produce significant decreases in gentamicin concentration, in the activity of the gentamicin eluate against a clinical isolate of S. aureus, the zone of inhibition of S. aureus, and in the compressive strength of the cement, after 7 d of immersion in the test solution. KW - gentamicin-loaded poly (methyl methacrylate) bone cement KW - total joint arthroplasty KW - total knee arthroplasty KW - tranexamic acid Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-246236 SN - 1996-1944 VL - 14 IS - 19 ER - TY - THES A1 - Heesen, Tobias T1 - Prüfung der Reliabilität, Validität und Änderungssensitivität der Kurzform des Funktionsfragebogens Bewegungsapparat (SMFA-D) bei Patienten mit Gonarthrose und Knieendoprothesenimplantation T1 - Reliability, validity and ressponsivness of the short form musculoskeletal assessment questionnaire (SMFA-D) at patients with primary osteoarthristis of the knee and undergoing total knee arthroplasty N2 - Die subjektive Beurteilung von Behandlungsergebnissen durch den Patienten hat in der Knieendoprothetik zunehmend an Bedeutung gewonnen. Patienten sind in der Lage ihren Gesundheitszustand reliabel und valide zu beurteilen. Instrumente zur Selbsteinschätzung werden als krankheitsspezifisches oder den allgemeinen Zustand erfassendes (generisches) Instrument unterschieden. Als klassifikatorisch zwischen beiden Instrumenten liegend, ist der SMFA zu sehen. Er wurde von Orthopäden in den Vereinigten Staaten entwickelt und ist bei entzündlichen, traumatischen und degenerativen Erkrankungen des Bewegungsapparates einsetzbar. Ziel dieser Arbeit ist es die deutsche Version, SMFA-D, auf ihre Testgütekriterien bei 67 Patienten mit Gonarthrose und Gelenksendoprothetischen Knieersatz zu überprüfen. Die Retesreliabilität für den Funktionsindex des SMFA-D lag bei r=0,88 und für den Beeinträchtigungsindex r=0,71. Ein Vergleich mit dem Knee-Score, SF-36 und dem WOMAC wurde zum Nachweis der Konstruktvalidität durchgeführt. Hierbei korrelierte der SMFA-D über den gesamten Untersuchungszeitraum mit dem SF36 (p<0,05 bis p<0,001) und zu den ersten beiden Untersuchungszeiträumen mit dem WOMAC (p<0,001). Der Knee-Score zeigte postoperativ signifikante Korrelationen (p<0,05 bis p<0.001). Die Kriteriumsvalidität wurde mit dem SMFA-Validitätstest prae-OP und post-OP nachgewiesen. Die Arzteinschätzung der Funktionseinbuße (p<0,001), die selbst gewählte Gehgeschwindigkeit (p<0,001), die Schmerzeinschätzung(p<0,01) und der Arthroseschweregradscore (p<0,05) korrelierten signifikant mit dem praeoperativen SMFA-D. Zur Überprüfung der diskriminanten Validität wurden Patienten mit und ohne Voroperation (nicht signifikant), mit und ohne Schmerzmitteleinnahme (p<0,006) sowie die Nutzung von Gehhilfen (p<0,02) unterschieden. Der SMFA-D erfüllte alle Testgütekriterien und erwies sich als praktikables Instrument. Er konnte den Effekt einer Knieendoprothesenimplantation im Verlauf aufzeigen (Funktionsindex: 0,86 nach drei Monaten, 0,89 nach einem Jahr; Beeinträchtigungsindex: 0,53 nach drei Monaten, 0,64 nach einem Jahr). Eine größere Effektstärke zeigte der SMFA-D in den vergleichenden Skalen des SF-36 (0,06 bis 0,79, ohne Subskala für Schmerz: 0,95 bis 1,19), eine gleiche beim WOMAC (0,40 bis 1,07) und Knee-Score (0,50 bis 1,93). Der SMFA-D konnte Patientengruppen mit oder ohne Schmerzmedikation und mit oder ohne Gehhilfen unterscheiden. Die Ergebnisse dieser Arbeit deuten darauf hin, das der SMFA-D als geeignetes Instrument in der Lage ist, den Gesundheitszustand und Verlauf von Patienten mit primärer Gonarthrose und endoprothetischen Kniegelenksersatz darzustellen. Als neues Instrument ist der SMFA-D in der Lage ein größeres Spektrum an muskuloskeletalen Erkrankungen abzudecken als ein erkrankunkspezifisches. Im Vergleich weist er ein ebenso hohes Ansprechverhalten wie generische Instrumente auf. N2 - The patient-based evaluation of outcome is gaining increased importance. The aim of the study was to translate and culturally adapt the short musculoskeletal function assessment questionnaire (SMFA) into German and to evaluate the practicability, the validity and responsiveness of the German version (SMFA-D) at 67 patients, undergoing total knee arthroplasty by osteoarthritis of the knee. A comparison between the short form (SF)-36, the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) and the knee-score of the Knee-Society was done. All instruments were sensitive to change, demonstrating the effect of total knee arthroplasty at 1-year follow-up. The SMFA-D effect sizes in comparable scales were bigger than in the SF-36 and similar to those of the WOMAC. Significant correlations of the SMFA-D indices with the SF-36, the WOMAC and the Knee-Score preoperatively could be shown. After 1-year follow-up, all correlations between the SMFA-D indices and the SF-36 scales were significant. In other comparison, only the correlation between the SMFA-D function index and the WOMAC function scales remained significant. The correlation of the SMFA-D function index with external validation criteria was higher than that using the other instruments. We recommend the SMFA-D for assessing change in functional status of patients with primary osteoarthritis of the knee following athroplasty. KW - Reliabilität KW - Validität KW - Änderungssensitivität KW - Funktionsfragebogen Bewegungsapparat (SMFA-D) KW - Knieendoprothese KW - Reliability KW - validity KW - responsivness KW - short form musculoskeletal assessment questionnaire (SMFA-D) KW - total knee arthroplasty Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-17306 ER -