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Purpose: The implantation rate of total knee arthroplasties (TKA) is continuously growing. Aseptic problems are a major cause of revision. The aim of the following study was to determinate the incidence of aseptic revisions in primary knee arthroplasty as well as aseptic revision rates and influencing factors according to the patients' age and type of procedure. Methods: Data collection was performed using the German Arthroplasty Registry. Influencing factors were analyzed according to the patients' age and type of procedure. Risk factors were calculated using multiple Log-rank test with the Holm's method. Incidence and comparison of aseptic revisions according to the patients' age and type of procedure were analyzed using Kaplan-Meier-estimates. Cox regression was applied to calculate the hazard ratio. Results: Overall, 300,998 knee arthroplasties with 254,144 (84.4%) unconstrained TKA, 9,993 (3.3%) constrained TKA and 36,861 (12.3%) unicondylar knee arthroplasties (UKA) were analyzed. Patients younger than 65 years suffered a significantly higher aseptic revision rate than older patients (p < 0.0001). After one year, a revision rate of 1.1% was recorded for patients 65–74 years, 1.6% for patients under 65 years, and 1.3% for patients beyond 74 years. After seven years, patients younger than 65 years sustained in 5.0%, patients 65–74 years in 2.9% and patients beyond 74 years in 2.4% revision. In unconstrained TKA, an increased Elixhauser-score (HR = 1,75; HR = 1,54; HR = 1,7; p < 0,001) was a risk factor regardless the age. A TKA volume of 101–250 regardless the age (HR = 0,66; HR = 0,69; HR = 0,79) and > 250 under 75 years (< 65: HR = 0,72; 65–74: HR = 0,78; p = 0,001) were protective for aseptic revision. In UKA, male gender (HR = 0,81; HR = 0,72; HR = 0,57; p < 0,001), a UKA volume ≥ 51 for patients under 75 years (< 65: HR = 0,62; 65–74: HR = 0,59; p = 0,003) as well as cemented UKA for patients younger than 75 years (< 65: HR = 0,37; 65–74: HR = 0,37; p < 0,001) were detected as preventive factors. Conclusion: A significant increased rate of aseptic revisions was reported for patients younger than 65 years compared to older patients. An increased Elixhauser score was a risk factor, whereas male and a high volume of performed UKA or TKA could be identified as preventive factors. Level of evidence: III, cohort study. [ABSTRACT FROM AUTHOR]

Purpose: Due to ageing population, the implantation rate of total knee arthroplasties (TKAs) is continuously growing. Aseptic revisions in primary knee arthroplasty are a major cause of revision. The aim of the following study was to determinate the incidence and reasons of aseptic revisions in constrained and unconstrained TKA, as well as in unicondylar knee arthroplasties (UKAs). Methods: Data collection was performed using the German Arthroplasty Registry. Reasons for aseptic revisions were calculated. Incidence and comparison of aseptic revisions were analysed using Kaplan–Meier estimates. A multiple χ2 test with Holm's method was used to detect group differences in ligament ruptures. Results: Overall, 300,998 cases of knee arthroplasty with 254,144 (84.4%) unconstrained TKA, 9993 (3.3%) constrained TKA and 36,861 (12.3%) UKA were analysed. Aseptic revision rate in UKA was significantly increased compared to unconstrained and constrained TKA (p < 0.0001). In constrained TKA, a 2.0% revision rate for aseptic reasons were reported after 1 year, while in unconstrained TKA 1.1% and in UKA, 2.7% of revisions were identified. After 7 years in constrained TKA 3.3%, in unconstrained TKA 2.8%, and in UKA 7.8% sustained aseptic revision. Ligament instability was the leading cause of aseptic revision accounting for 13.7% in unconstrained TKA. In constrained TKA, 2.8% resulted in a revision due to ligament instability. In the UKA, the most frequent cause of revisions was tibial loosening, accounting for 14.6% of cases, while progression of osteoarthritis accounted for 7.9% of revisions. Ligament instability was observed in 14.1% of males compared to 15.9% of females in unconstrained TKA and in 4.6% in both genders in UKA. Conclusion: In patients with UKA, aseptic revision rates are significantly higher compared to unconstrained and constrained TKA. Ligament instability was the leading cause of aseptic revision in unconstrained TKA. In UKA, the most frequent cause of revisions was tibial loosening, while progression of osteoarthritis was the second most frequent cause of revisions. Comparable levels of ligament instability were observed in both sexes. Level of Evidence: Level III, cohort study. [ABSTRACT FROM AUTHOR]

Las consolidaciones viciosas de fracturas intraarticulares de falanges provocan deformidades que limitan funcionalmente y son mal toleradas. Por otra parte, su tratamiento mediante osteotomías intraarticulares está asociado a la aparición de complicaciones, principalmente la rigidez. Este artículo presenta dos casos de consolidaciones viciosas intraarticulares tratadas mediante una osteotomía extraarticular y síntesis por un método poco invasivo, el tornillo endomedular. Tras dicho procedimiento, los pacientes presentaron un rango de movimiento completo y una vuelta a sus actividades sin dolor en menos de 3 meses. Las ventajas principales de la técnica descrita son, por un lado, la evitación de las complicaciones secundarias a procedimientos intraarticulares, y, por otro, el uso de dispositivos que precisan abordajes menos agresivos y desperiostizaciones menos amplias.

Purpose: There is concern that using cementless components may increase polyethylene wear of the Oxford unicompartmental knee replacement (OUKR). Therefore, this study aimed to measure bearing wear at 10 years in patients from a randomized trial comparing Phase 3 cemented and cementless OUKRs and to investigate factors that may affect wear. It was hypothesized that there would be no difference in wear rate between cemented and cementless OUKRs. Methods: Bearing thickness was determined using radiostereometric analysis at postoperative, 3‐month, 6‐month, 1‐year, 2‐year, 5‐year and 10‐year timepoints. As creep occurs early, wear rate was calculated using linear regression between 6 months and 10 years for 39 knees (20 cemented, 19 cementless). Associations between wear and implant, surgical and patient factors were analysed. Results: The linear wear rate of the Phase 3 OUKR was 0.06 mm/year with no significant difference (p = 0.18) between cemented (0.054 mm/year) and cementless (0.063 mm/year) implants. Age, Oxford Knee Score, component size and bearing thickness had no correlation with wear. A body mass index ≥ 30 was associated with a significantly lower wear rate (p = 0.007) as was having ≥80% femoral component contact area on the bearing (p = 0.003). Bearings positioned ≥1.5 mm from the tibial wall had a significantly higher wear rate (p = 0.002). Conclusions: At 10 years, the Phase 3 OUKR linear wear rate is low and not associated with the fixation method. To minimize the risk of wear‐related bearing fracture in the very long‐term surgeons should consider using 4 mm bearings in very young active patients and ensure that components are appropriately positioned, which is facilitated by the current instrumentation. Level of Evidence: Level III, retrospective comparative study. [ABSTRACT FROM AUTHOR]

Total knee arthroplasty allows immediate postoperative weight-bearing and is increasingly recognized as a suitable treatment option for older patients who have tibial plateau fractures (TPFs). This systematic review evaluated the clinical and functional outcomes associated with primary versus secondary TKA for the treatment of TPFs in patients aged ≥55 years. Various databases were searched from inception to December 2021. Studies investigating outcomes of primary TKA (pTKA) as the initial treatment for TPFs in patients of mean age ≥55 years or those investigating outcomes of secondary TKA (sTKA) following any other primary treatment for TPFs were included. Quality of included studies was assessed using a methodological scale. Of 767 potentially relevant studies, 12 studies comprising 341 patients were included: 121 patients underwent (pTKA) and 220 patients underwent sTKA. There were 3 high-quality studies. Patients in the sTKA cohort were significantly younger at the time of TKA compared with those undergoing pTKA (mean 61.3 versus 72.2 years, P <.001, 95% confidence interval (CI) 8.2 to 13.6). Intraoperative and postoperative complication rates were lower with pTKA; in particular, sTKA was associated with a significantly increased rate of stiffness requiring reintervention and patella tendon rupture. Functional outcome was greater after pTKA, but this did not reach statistical significance (85.2 versus 79.9%, P =.359, 95% CI -16.7 to 6.1). Primary TKA was associated with lower complication rates than secondary TKA after TPF. In appropriate cases of TPF in older adults, it may be preferable to proceed with TKA as primary treatment rather than delaying until after fracture union or malunion. [ABSTRACT FROM AUTHOR]

Introduction: Arthroplasty-associated bone loss remains a clinical problem: stiff metallic implants disrupt load transfer to bone and, hence, its remodeling stimulus. The aim of this research was to analyze how load transfer to bone is affected by different forms of knee arthroplasty: isolated partial knee arthroplasty (PKA), compartmental arthroplasty [combined partial knee arthroplasty (CPKA), two or more PKAs in the same knee], and total knee arthroplasty (TKA).Methods: An experimentally validated subject-specific finite element model was analyzed native and with medial unicondylar, lateral unicondylar, patellofemoral, bi-unicondylar, medial bicompartmental, lateral bicompartmental, tricompartmental, and total knee arthroplasty. Three load cases were simulated for each: gait, stair ascent, and sit-to-stand. Strain shielding and overstraining were calculated from the differences between the native and implanted states.Results: For gait, the TKA femoral component led to mean strain shielding (30%) more than three times higher than that of PKA (4%–7%) and CPKA (5%–8%). Overstraining was predicted in the proximal tibia (TKA 21%; PKA/CPKA 0%–6%). The variance in the distribution for TKA was an order of magnitude greater than for PKA/CPKA, indicating less physiological load transfer. Only the TKA-implanted femur was sensitive to the load case: for stair ascent and gait, almost the entire distal femur was strain-shielded, whereas during sit-to-stand, the posterior femoral condyles were overstrained.Discussion: TKA requires more bone resection than PKA and CPKA. These finite element analyses suggest that a longer-term benefit for bone is probable as partial and multi-compartmental knee procedures lead to more natural load transfer compared to TKA. High-flexion activity following TKA may be protective of posterior condyle bone resorption, which may help explain why bone loss affects some patients more than others. The male and female bone models used for this research are provided open access to facilitate future research elsewhere.

Coronal-plane intra-articular fractures of the femoral condyle (Hoffa fractures) are rare, and difficult to diagnose and treat. They mostly result as a consequence of high-energy trauma and are combined with concomitant fractures (patellar, tibia shaft) and/or soft-tissue damage. A plain X-ray can miss the diagnosis initially and therefore computerized tomography scan is recommended, which can also help in the preoperative planning. The vast majority of these fractures are unicondylar (mostly lateral condyle fractured). The approach for their treatment can be anterior or posterior. In cases of fracture comminution, much more mutilant approaches with osteotomy have been described. A combined two-stage approach can be used to obtain anatomical reduction and fixation of all the fragments. We present a case of a 46-year-old male patient with comminuted lateral Hoffa fracture treated with a combined approach (extended posterior approach to the proximal tibia and lateral parapatellar) in a time interval of one month. [ABSTRACT FROM AUTHOR]

Aim: Unicondylar knee arthroplasty (UKA) is among the treatment options for patients with arthritis limited to one compartment of the knee. Fixed-bearing (FB) and mobile-bearing (MB) inserts are present. This study aimed to compare functional and clinical outcomes and revision rates of patients operated with FB-UKA and MB-UKA. Material and Methods: A total of 131 knees of 118 patients underwent cemented UKA, with a mean follow-up period of 80.58±31.31 months for FB-UKA and 97.66±29.24 months for MB-UKA. Clinical and functional evaluation was performed by the Knee Society Score (KSS) and Western Ontario and McMaster Universities Arthritis Index (WOMAC) score, at the last follow-up visit. The factors affecting the radiological and functional results, complication, and revision rates were examined under three main titles; i) surgeon-related, ii) patient-related, and iii) component alignment-related factors. Results: There was no significant difference between the groups in terms of age, gender, body mass index, and side. Regarding the KSS scores, 9 (6.87%) knees were within acceptable limits, 62 (47.32%) knees were found to be good, and 60 (45.80%) knees were found to be excellent. No statistically significant difference was found between groups (p=0.497). Regarding the WOMAC scores, the MB-UKA group had significantly lower pain (p=0.049) and stiffness (p=0.014), but similar functional (p=0.591) scores. There was no statistically significant difference regarding revision rates (p=0.931). Conclusion: Similar clinical, functional, and radiological results and low revision rates were found. In terms of pain and joint stiffness, a significant difference was found between groups, in favor of MB-UKA.

Aim: There are few studies in the literature evaluating the robotic assisted unicondylar knee arthroplasty (rUKA) learning curve. This study aimed to evaluate the learning curve in robotic assisted unicondylar knee arthroplasty in terms of operation time. Materials and Methods: The data of patients who underwent rUKA between October 2016 and December 2019 were retrospectively analyzed. Age, gender, side, and body mass index (BMI) values of the patients were obtained from the patient files. To compare the operation times, the patients were divided into two groups. The first group represented patients who had surgery in the first half of the follow-up period (n=27), while the last group represented patients who had surgery in the second half of the follow-up period (n=28). Results: During the study period, rUKA was performed on 55 patients (42 females, 13 males) with a mean age of 64.1 years. The demographic data of the two groups were similar. The mean operative times of the first (n=27) and the last groups (n=28) were 101.816.1 minutes, and 84.89.9 minutes, respectively (p <0.001). Conclusion: The mean duration of operation was significantly shorter in the last group who underwent rUKA, compared to the first group. Our findings showed that there is a significant learning curve in rUKA surgery in terms of operation time. [ABSTRACT FROM AUTHOR]

Introduction:Despite a faster recovery, low complication rate, and good functional results, it has been reported that unicondylar knee arthroplasty (UKA) may have high revision rates. Aseptic loosening and pain are the most common causes of UKA revision. The use of cementless and hybrid UKA has been presented as a solution to improve the fixation of prosthetic components. The main purpose of this study was to compare the early clinical outcomes and quality of fixation of cementless and hybrid UKA radiologically.Methods:A retrospective study was established with patients who received 37 cementless and 41 hybrid UKA in a minimum 2-year follow-up period. The patients’ clinical outcomes were evaluated using the Oxford knee score, EuroQol-5 dimensions, EuroQol-visual analog scale, knee injury and osteoarthritis outcome score, and knee range of motion. The fixation of UKA components was evaluated with the varus-valgus angle of the tibial-femoral component, and the incidence of the radiolucent (RL) line at both the tibial and femoral componentbone interface on the radiograph.Results:There was no significant difference in any clinical outcome measurement (p>0.05). There was no significant difference between the varus-valgus and flexion-extension angles of the femoral and tibial components in both groups (p>0.05). There were significantly more tibial RL in the hybrid group than in the cementless group (p=0.025). There was no significant difference in the incidence of RL at the femoral component-bone interface (p=0.691).Conclusion:The cementless group showed significantly less tibial RL than the hybrid group in UKA. Although there were no clinically significant differences between cementless and hybrid UKAs, cementless UKA may be preferred to prevent possible prosthesis loosening.

Background: Unicondylar knee arthroplasty (UKA) is an accepted treatment option for unicompartmental femorotibial degeneration and is gaining in popularity. The goal of this review is to evaluate the top 50 most cited articles pertaining to UKA to better help surgeons understand the trends, identify influential articles, and navigate this body of literature more effectively. Methods: The Institute for Scientific Information Web of Knowledge database was used to identify all articles related to UKA. The initial screening was based on the number of citations for each article. The list was then refined to include only peer-reviewed original articles, review articles, or editorials. Data were extracted from the articles to rank the articles in the descending order from the most citations to the least. Results: Initial search yielded 1844 articles. Fifty were identified to match the study criteria. The highest ranked article was cited a total of 463 times, whereas the lowest ranked article was cited 101 times. The average total number of citations per publication was 162. The earliest article on the list was published in 1978. The majority of publications assessed long-term outcomes of UKA (n = 6, 52%). The majority of articles were graded a level of evidence of III (n = 21 42%), whereas only 3 articles were graded a level I. Conclusions: This review provides a quantitative analysis of the most-cited literature pertaining to UKA, which has a paucity of level I studies.

Purpose: The Oxford unicompartmental knee replacement (UKR) has a fully congruent mobile bearing to minimise wear. However, with younger higher demand patients, wear remains a concern. The aim of this study was to quantify the wear rate of Phase 3 Oxford UKR bearings over the course of 5 years and to identify the factors that influence it. Methods: 40 medial Oxford UKRs recruited for a randomised study of cemented and cementless fixation were studied with Radiostereometric analysis (RSA) at 1 week, 3 months, 6 months, 1 year, 2 years, and 5 years post-operatively and bearing thickness was calculated. Penetration, defined as the change in thickness compared to the 1-week measurement, was determined. Creep (early penetration) and wear (late penetration at a constant rate) were calculated. The influence of demographic factors, Oxford Knee Score (OKS), Tegner score, fixation and bearing overhang (determined by RSA) on wear was analysed. Results: After 6 months the penetration rate was constant, indicating that wear alone was occurring. The wear rate was 0.07 mm/year (SD 0.03). The creep was 0.06 mm with about 95% occurring during the first 3 months. There was no significant relationship between fixation (cemented/cementless), age, component size, OKS and Tegner score with wear rate. Increasing BMI was associated with decreasing wear (p = 0.042). 37/40 bearings overhung the tibia to some extent and 23/40 overhung the tibia medially. An increase in the area of overhang (p = 0.036), amount of medial overhang (p = 0.028) and distance between the bearing and tibial wall (p = 0.019) were associated with increased wear. Bearings that did not overhang (0.06 mm/year) had less wear (p = 0.025) than those that did (0.08 mm/year). There was no relationship (p = 0.6) between the femoral contact area and wear. Conclusion: During the first three to six months after implantation, the bearing becomes 0.06 mm thinner due to creep. The combined wear rate of the upper and lower surfaces of the bearing is constant (0.07 mm/year). The wear is lower if the bearing does not overhang the tibia so surgeons should aim for the bearing to be close to the tibial wall. The orientation of the femoral component does not influence wear. Level of evidence: Retrospective Study, Level III. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to report and compare the long-term revision rate, revision indications and patient reported outcome measures of cemented and cementless unicompartmental knee replacements (UKR). Methods: Databases Medline, Embase and Cochrane Central of Controlled Trials were searched to identify all UKR studies reporting the ≥ 10 year clinical outcomes. Revision rates per 100 component years [% per annum (% pa)] were calculated by fixation type and then, subgroup analyses for fixed and mobile bearing UKRs were performed. Mechanisms of failure and patient reported outcome measures are reported. Results: 25 studies were eligible for inclusion with a total of 10,736 UKRs, in which there were 8790 cemented and 1946 cementless knee replacements. The revision rate was 0.73% pa (CI 0.66–0.80) and 0.45% pa (CI 0.34–0.58) per 100 component years, respectively, with the cementless having a significantly (p < 0.001) lower overall revision rate. Therefore, based on these studies, the expected 10-year survival of cementless UKR would be 95.5% and cemented 92.7%. Subgroup analysis revealed this difference remained significant for the Oxford UKR (0.37% pa vs 0.77% pa, p < 0.001), but for non-Oxford UKRs there were no significant differences in revision rates of cemented and cementless UKRs (0.57% pa vs 0.69% pa, p = 0.41). Mobile bearing UKRs had significantly lower revision rates than fixed bearing UKRs in cementless (p = 0.001), but not cemented groups (p = 0.13). Overall the revision rates for aseptic loosening and disease progression were significantly lower (p = 0.02 and p = 0.009 respectively) in the cementless group compared to the cemented group (0.06 vs 0.13% pa and 0.10 vs 0.21% pa respectively). Conclusions: Cementless fixation had reduced long-term revision rates compared to cemented for the Oxford UKR. For the non-Oxford UKRs, the revision rates of cementless and cemented fixation types were equivalent. Therefore, cementless UKRs offer at least equivalent if not lower revision rates compared to cemented UKRs. Level of evidence: III. [ABSTRACT FROM AUTHOR]

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Background: The thickness of the polyethylene bearing in medial unicondylar knee arthroplasty (UKA) is determined by the depth of the tibial resection, degree of correctable deformity, and balance of the knee. The purpose of this study is to evaluate whether polyethylene thickness in medial mobile-bearing UKA impacts clinical outcomes and survivorship.Methods: A retrospective review from 2004 to 2017 identified patients who underwent a primary mobile-bearing medial UKA with 2-year minimum follow-up or revision. A total of 2305 patients (3030 knees) met inclusion criteria. Patients were divided in 2 groups: thin bearing (group 1): 3-mm or 4-mm bearing and thick bearing (group 2): ≥ 5 mm. The thin group consisted of 2640 knees (87%), whereas the thick group had 390 knees (13%). Preoperative and postoperative demographics, range of motion, Knee Society scores, complications, and reoperations were evaluated.Results: Mean follow-up was 5.2 years (range, 0.5 to 12.6). There was no significant difference between groups in postoperative range of motion or Knee Society scores (P > .05). Manipulations were performed in 1.3% of patients and not significantly different between groups. The all-cause revision rate for group 1 was 4.02% and group 2 was 4.58% (P = .6). Revision rates for tibial aseptic loosening were significantly higher in group 2 (1.8%) than those in group 1 (0.7%) (P = .04). There was no significant difference in failure rates between groups for tibial collapse or fracture, femoral aseptic loosening, arthritic progression, bearing dislocation, or other cause of revision.Conclusion: This study demonstrated that thicker bearings in medial UKA increased the risk of tibial aseptic loosening, but not all-cause failures or clinical outcomes. [ABSTRACT FROM AUTHOR]

Copyright of Istanbul Medical Journal is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To evaluate whether long-term (10-year minimum) patient outcomes and survival of fixed-bearing medial unicompartmental knee arthroplasty (UKA) in patients aged ≤ 60 years were favorable despite non-conventional age criteria. Methods: The authors reviewed the records of 91 consecutive medial UKAs performed in patients aged ≤ 60 by a single surgeon. All patients received the same fixed-bearing M/G Unicompartmental Knee System. Patients records were updated, noting complications or revisions, and Oxford Knee Scores and overall satisfaction collected. If deceased, the general practitioner or next of kin provided data. Results: Of the initial 91 knees, 10 were revised, 6 were deceased, and 1 was lost to follow-up. The final cohort of 74 knees was aged 54.3 ± 4.3 years (range 41.8–60.6) at index surgery. Using revision of any component as endpoint, the present series had a KM survival of 92.9% (CI 84.8–96.7%) at 10 years, and 87.8% (CI 78.4–93.2%) at 15 years, and a single non-fatal DVT was reported. At final follow-up of 15 ± 1.3 years (range 11–18), OKS (available for all 74 knees) was 38.4 ± 8.4 (range 18–48). Overall patients were pleased or very pleased with 72 of the knees (97%). Conclusion: Fixed-bearing medial UKA yields favorable results in the treatment of single compartment osteoarthritis of the knee in patients ≤ 60 years. The present study demonstrates low complication rates, good-to-excellent long-term patient outcomes, and satisfactory implant survival for this age group considering the advantages of UKA. Level of evidence: Level IV, retrospective cohort study. [ABSTRACT FROM AUTHOR]

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Background: Patients are often cautioned against a high level of activity after knee arthroplasty. The purpose of this study was to report on implant survivorship and outcomes of high-activity patients compared with low-activity patients after unicondylar knee arthroplasty (UKA).Methods: We identified 487 patients (576 knees) who underwent UKA with the Oxford mobile bearing knee (Zimmer Biomet, Warsaw, IN) with a 5-year minimum follow-up. Patients were divided into 2 groups: low activity (LA) (University of California Los Angeles ≤6) and high activity (HA) (University of California Los Angeles ≥7). Preoperative and postoperative range of motion, Knee Society scores, complications, and reoperations were evaluated.Results: Mean follow-up was 9 years (range, 4 to 13.1). The HA group had significantly more male patients, were younger, and had higher knee society clinical scores and knee society functional scores preoperatively. The HA group had significantly higher improvements in Knee Society scores and pain postoperatively. Revisions were performed in 8.4% of the LA group and 6.2% of the HA group (P = .43). At our mean of 9-year follow-up, there was 94.0% survival for the HA group and 92.1% for the LA group (P = .6085).Conclusions: Highly active patients had no increased risk of revision after UKA with the Oxford mobile bearing knee at 5-year minimum follow-up. [ABSTRACT FROM AUTHOR]

Background: Patient selection is key to the success of medial unicondylar knee arthroplasty (UKA). Progression of arthritis is the most common indication for revision surgery. Per-operative arthroscopy is a means of directly assessing the integrity of the lateral compartment. The aim of the study is to assess the long-term survivorship of UKA performed when per-operative arthroscopy is used as a final means of deciding whether to proceed with UKA., Methods: We used per-operative arthroscopy as a means to confirm suitability for UKA in a consecutive series of 279 Oxford medial UKA. Our series of UKA with per-operative arthroscopy (Group 1) was compared to all Oxford UKA (Group 2) and all UKA in the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) (Group 3)., Results: The 14-year cumulative percentage revision (CPR) was 18.5% (95% CI 12.7, 26.4) for group 1, 19.7% (95% CI 18.8, 20.6) for group 2, and 19.2% (95% CI 18.5, 19.8) for group 3. There was no statistically significant difference in the (CPR) for the entire period when group 1 was compared to groups 2 or 3. Progression of arthritis was least in Group 1 compared to groups 2 and 3; 3.6 versus 4.4 and 4.1% respectively. Following per-operative arthroscopy 21.6% (77/356) of knees underwent a change of surgical plan from UKA to TKA., Conclusion: In our practice, which includes per-operative arthroscopy, we have identified a reduced risk of revision due to progression of arthritis but no difference in overall long-term implant survivorship., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: In light of the existing lack of evidence, it was the aim of this study to compare gait characteristics and knee extensor strength after medial unicondylar knee arthroplasty (MUKA) with those after total knee arthroplasty (TKA), given the same standardized minimally invasive surgery (MIS) approach in both groups.Methods: Patients scheduled for MIS-MUKA or MIS-TKA as part of clinical routine were invited to participate. A posterior cruciate ligament-retaining total knee design was used for all MIS-TKA. A 3-dimensional gait analysis was performed preoperatively with a VICON system and at 8 weeks postoperative to determine temporospatial parameters, ground reaction forces, joint angles, and joint moments. At the same 2 times, isokinetic tests were performed to obtain peak values of knee extensor torque. A multivariate analysis of variance was conducted and included the main effects time (before and after surgery) and surgical group and the group-by-time interaction effect.Results: Fifteen MIS-MUKA patients and 17 MIS-TKA patients were eligible for the final analysis. The groups showed no differences regarding age, body mass index, sex, side treated, or stage of osteoarthritis. We determined neither intergroup differences nor time × group interactions for peak knee extensor torque or any gait parameters (temporospatial, ground reaction forces, joint angles, and joint moments).Conclusion: It is concluded that MUKA is not superior to TKA with regard to knee extensor strength or 3-dimensional gait characteristics at 8 weeks after operation. As gait characteristics and knee extensor strength are only 2 of the various potential outcome parameters (knee scores, activity scores…) and quadriceps strength might take a longer time to recover, our findings should be interpreted with caution. [ABSTRACT FROM AUTHOR]

Knee arthroplasty typically relieves pain and restores function, but dissatisfaction and early revision occur at a frequency that places a significant burden on patients and the health care system. A new generation of computer and robotic systems has been developed to help orthopaedic surgeons enhance precision and accuracy, with the hope of making outcomes more reliable. Surgical robots can be active, semiactive, or passive. Each level of robot autonomy vs surgeon control has potential benefits and limitations. Currently available robotic platforms are discussed in the context of historical developments, published outcomes, and future directions. [ABSTRACT FROM AUTHOR]

AIM: To report the long-term outcome, return to work and owner satisfaction, for working farm dogs in New Zealand following surgical repair of humeral condylar fractures. METHODS: A retrospective study of working dogs that had undergone surgical repair of one or more condylar fractures of the humerus was undertaken by searching the medical records of two referral veterinary clinics. The inclusion criteria were working dogs that had undergone open surgical reduction and internal fixation of a fracture of one or both humeral condyles. The ability of the dog to work after surgery, persistence of lameness and the owners' degree of satisfaction with the outcome were assessed from answers to a questionnaire. RESULTS: Sixteen dogs met the inclusion criteria and had owner questionnaires completed at a median follow-up interval of 54 (min 3, max 121) months. Fifteen were working farm dogs (13 Heading dogs, including Border Collies, and two New Zealand Huntaways) and one dog was a cross-breed used for pig hunting. Four dogs had two fractures on separate occasions, of which three underwent surgery on both elbows at a median interval of 19 months. Of the 20 humeral fractures, 10 were lateral condylar, one was a medial condylar fracture and nine were dicondylar fractures. Of the 16 repairs with follow-up data, seven (44%) dogs could perform all expected duties following surgical repair, whilst a further eight (50%) could perform most duties although some allowances had to be made for some limitation of their performance. Of the 15 owners responding, 13 (87%) were satisfied or very satisfied with the outcome of surgery and felt the surgery was worth the expense. Post-operative complications requiring a second surgery occurred in 7/20 (35%) dogs, and all six dogs that received appropriate surgical revision returned to work. CONCLUSIONS: In this small case series, surgical repair of humeral condylar fractures in working dogs had a good prognosis with 15/16 of treated dogs returning to full or substantial levels of work. CLINICAL RELEVANCE: These data provide veterinarians with relevant information regarding the outcome and prognosis of surgery for clients whose working dogs have fractured a humeral condyle. [ABSTRACT FROM PUBLISHER]

Purpose: The objective of the study was to clarify whether driving abstinence should be recommended when patients are discharged from hospital after unicompartmental knee arthroplasty (UKA). We tested the hypotheses that there are differences in the peri-operative course of brake response time in patients undergoing right-sided (1) or left-sided (2) UKA. Additionally, we tested whether brake response time is significantly influenced by pain (3), driving experience (4) or age (5). Methods: In 43 patients undergoing UKA, brake response time was measured with a custom-made driving simulator pre-operatively and 1 and 6 weeks after UKA. Patients' visual analogue scales for knee pain and their self-reported driving experience were also assessed. Results: In patients with right-sided UKA, brake response time changed from 786 (261) ms pre-operatively to 900 (430) ms 1 week post-operatively ( p = 0.029). At 6 weeks post-operatively, brake response time had returned to 712 (139) ms, which was deemed to be an insignificant change from the pre-operative reference benchmark. When surgery was performed on the contralateral left side, no effect was found onto the right side's brake response time. Knee pain and driving experience were significantly correlated with brake response time. No such correlations were found between brake response time and age. Conclusions: On the basis of the current findings, it is concluded that brake response time returns to pre-operative levels 6 weeks after UKA surgery. Therefore, it is proposed that driving be abstained from for that period. Level of evidence: Therapeutic study, Level IV. [ABSTRACT FROM AUTHOR]

Data regarding the posterior slope of the tibia (PTS) are limited and sometimes conflicting. The purpose of this study was to determine the native posterior tibial slope in patients undergoing a medial or lateral UKA. A retrospective review was performed on 2395 CT scans in patients indicated for UKA, and the PTS of the osteoarthritic compartment was measured relative to a plane set perpendicular to the sagittal, tibial mechanical axis. The mean preoperative PTS in patients undergoing medial UKA was 6.8° + 3.3°, with 34.3% between 4° and 7°. The mean preoperative PTS in patients undergoing lateral UKA was 8.0° + 3.3°, with 27.5% between 4° and 7°. If attempting to recreate a patient's preoperative tibial slope, a routine target of 5° to 7° will produce a posterior slope less than the patient's native anatomy in 47% of patients undergoing UKA. This is the first, large CT-based review of posterior slope variation of the proximal tibia in patients undergoing UKA. [ABSTRACT FROM AUTHOR]

Abstract: An 18 year old male patient was hit by a car to his motorcycle causing a unicondylar Hoffa fracture and an ipsilateral patella fracture. Hoffa fracture is a rare lesion and this association of injury has not been reported before. [Copyright &y& Elsevier]

Unicondylar knee replacement systems have been shown to perform comparably to total knee replacements, while being much less surgically invasive. Proper ligament balancing, as well as knee laxity, has been shown to play an important role in optimizing kinematic behavior of these implant systems and improving long-term survival of the implant. This study investigates the effect of different simulated ligament laxity conditions of the anterior cruciate ligament and the posterior cruciate ligament on the resulting anteroposterior and mediolateral contact kinematics for medial and lateral pairs of UKR implants with flat and symmetric ultrahigh-molecular-weight polyethylene inserts during force-controlled ISO-14243-1 knee testing simulation. A novel method of capturing the tibiofemoral lowest point contact path was used to calculate the shear plane lowest point contact path kinematics in both the anteroposterior and the mediolateral directions. The results illustrated that multiple clinically relevant soft tissue configurations produce statistically different measured knee kinematics in unicondylar knee replacement systems than is seen in accepted “standard” knee simulator protocols with 95% confidence interval. The observed kinematic differences in anteroposterior and mediolateral movement from what was observed using standard wear testing protocols could aid in the development of unicondylar knee replacement design enhancements that are resistant to varying soft tissue deficiencies. [ABSTRACT FROM AUTHOR]

The purpose of our study was to evaluate retrospectively the mid-term results of the Miller-Galante II (Zimmer, Warsaw, USA) unicondylar knee arthoplasty (UKA). The study included 46 patients with medial UKAs. Mean follow-up time was 7.0 years (range 2.7–13.1 years). Survival rate of the prosthesis was 86.6% (95% CI 73.7–99.6) at 7 years. The mean clinical and functional Knee Society Scores had increased from 51 and 62 points preoperatively to 76 and 93 points ( P < 0.001) postoperatively. Five of the 46 knees were revised because of excessive wear of the polyethylene liner, and three due to progression of the osteoarthritis in the lateral compartment of the knee. Survival of this fixed-bearing UKA was not as good as previously reported and polyethylene wear seems to be a more common problem than previously assumed. [ABSTRACT FROM AUTHOR]

We describe the technique for performing lateral unicompartmental arthroplasty through either a medial or lateral parapatellar approach. A lateral unicompartmental arthroplasty is a technically more demanding procedure than its more common medial counterpart. Studies that exist on lateral unicompartmental arthroplasty show good outcomes. The key steps to the procedure involve a figure-of-four leg position to improve visualization of the lateral compartment, avoiding patella femoral impingement by downsizing the femoral component, avoiding external rotation of the tibial component, and lateralizing the femoral component to improve contact with the tibial implant. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses the case of two dogs which experience non-weight-bearing lameness of a hindlimb after jumping or falling with the leg trapped in a gate. According to the article, among the clinical findings include pain and swelling and a radiograph revealed that a fracture of the medical condyle of the distal femur. In addition, it affirms that open reduction and internal fixation have been used to cure the disease, with the former being achieved after the insertion of the medial collateral ligament from the tibia and the latter through the use of K-wires and biodegradable pin.

The article presents information on the technique of biunicondylar knee arthroplasty (BiUKA). It says a patient undergoing this surgical technique is positioned as for a total knee arthroplasty (TKA), lying supine with a pneumatic tourniquet around the thigh root. The step-by-step processes involved in the surgery are also discussed including the tibial preparation, tibial cut, and femoral resurfacing.

Prospective multicentric study on unicondylar knee arthroplasties using the minimally invasive method described by Repicci. Three hundred and seventy nine unicondylar knee arthroplasties in patients with an average age of 66 years were examined preoperatively and 40 weeks postoperatively. In 98.4% of the cases the medial compartment was replaced. The examination was documented using the Knee Society Score (KSS). Radiological examination was done using films of the knee in two planes in standing position and a long leg axis film. The mean KSS increased significantly (P<0.005) from 100.1 (SD 21.7) before surgery to 179.1 (SD 24.0) postoperatively. Ninety-five of the patients were subjectively satisfied with the procedure. Using correlation analysis, we found that osteoarthritic changes of the patella had a highly significant (p=0.001) influence on the KSS results. Patient's age and the pain subscale of the KSS also had a highly significant (p=0.01) influence on the KSS result. Short-term results of the Repicci unicondylar arthroplasty using the minimally invasive technique are encouraging in terms of patient satisfaction. It became apparent that osteoarthritic changes of the patella, flexion contractures and extension deficits have a considerable influence on the overall result. [ABSTRACT FROM AUTHOR]

The aim of the present study was the evaluation of differences in clinical results, proprioceptive performance and gait in patients with unicondylar and bicondylar sledge prostheses of the knee. In a retrospective study, 17 patients with unicondylar sledge prostheses were compared with 15 patients with bicondylar sledge prostheses. Clinical examination was rated using HSS, Knee Society, and patellar scores and a visual analogue scale for pain. Proprioceptive performance was examined using sway measurements during single leg stance on a force platform. In addition, the patients underwent 3-D gait analysis including measurements of ground reaction forces and surface electromyographic (EMG) investigation of the lower extremity. Comparing both patient groups in clinical scores, gait, EMG and proprioception, no significant differences were found. Implantation of bicondylar sledge prostheses retaining both cruciate ligaments achieves functional results as good as unicompartmental arthroplasty. The presented results might encourage future research on new models of total joint replacement with preservation of both cruciate ligaments. [ABSTRACT FROM AUTHOR]