Unicompartmental Knee Arthroplasty Group Research Articles

A comparative study of single-stage bilateral vs. unilateral medial unicompartmental knee arthroplasty on complications, clinical outcomes, and costs.

This retrospective study aimed to evaluate the short-term recovery and cost-effectiveness of bilateral unicompartmental knee arthroplasty (UKA) compared to staged unilateral UKA. The study analyzed postoperative pain scores, medical costs, and complications in patients with knee osteoarthritis who underwent these procedures. A total of 226 patients who received either unilateral UKA (Group A, n = 170) or bilateral UKA (Group B, n = 56) using the mobile-bearing UKA were included in the study. Patient demographics, surgical details, postoperative pain scores, knee range of motion, length of hospital stay, self-controlled analgesic use, total medical costs, and complications were retrospectively collected from medical records. The demographic characteristics were comparable between the groups. Group B had a longer surgical time and higher medical costs than Group A. However, there were no significant differences in hospital stay, pain scores, or knee range of motion between the two groups. Complications were infrequent and not significantly different. Insert dislocation and loosening were the most common complications. Patient-controlled analgesia effectively reduced pain scores in Group A but not in Group B. Bilateral UKA does not significantly affect hospital stay, postoperative pain, or complications compared to unilateral UKA. Although bilateral UKA requires longer surgical time and incurs higher costs, it offers the potential benefit of reducing anesthesia-related complications and overall health insurance expenditures. This study recommends bilateral UKA as a suitable option for patients with bilateral knee osteoarthritis, given its comparable short-term outcomes and potential cost-saving advantages. III.

Cemented versus cementless Oxford unicompartmental knee arthroplasty for the treatment of medial knee osteoarthritis: an updated systematic review and meta-analysis.

This meta-analysis sought to compare the efficacy of cemented versus cementless Oxford unicompartmental knee arthroplasty(UKA) for the treatment of medial knee osteoarthritis. A comprehensive search of the following databases was conducted: Pubmed, The Cochrane Library, China National Knowledge Infrastructure (CNKI), Embase, the Web of Science, and MEDLINE. The objective was to identify literature comparing cemented versus cementless Oxford unicompartmental knee arthroplasty for the treatment of medial knee osteoarthritis. Duplicate literature, low-quality literature, literature with incompatible observations, and literature for which the full text was not available were excluded. Two independent researchers employed the Cochrane Risk Assessment Tool and the Newcastle-Ottawa Scale (NOS) to evaluate the quality of the included literature. The data then were extracted and subsequently meta-analyzed using RevMan 5.4. A total of 12 papers were included in the analysis, encompassing a cumulative of 2558 cumulative cases. Of these, 1258 were cemented and 1300 were cementless. A meta-analysis was conducted to compare the outcomes of cemented versus cementless Oxford UKA. The Oxford UKA group exhibited a significantly longer surgery time than the cementless Oxford UKA group [mean difference (MD) = 9.91, 95% confidence interval (CI) (7.64,12.17)]. Additionally, the cemented Oxford UKA group demonstrated a significantly lower knee OKS score compared to the cementless Oxford UKA group. The mean difference (MD) was - 1.58 (95% CI: -2.30, -0.86), indicating a significantly lower score for the cemented Oxford UKA group. Similarly, the mean difference (MD) was - 1.8 for the knee KSS clinical score, indicating a significantly lower score for the cemented Oxford UKA group. The results demonstrated that the knee KSS functional score was significantly lower in the cemented Oxford UKA group than in the cementless Oxford UKA group [MD=-1.72, 95% CI (-3.26, -0.37)]. 95% CI (-3.27,-0.17)], the cemented Oxford UKA group exhibited a significantly higher incidence of radiolucent lines around the prosthesis than the cementless Oxford UKA group [ratio of ratios (OR) = 3.62, 95% CI (1.08,12.13)]. The revision rate was significantly higher in the cemented Oxford UKA group than in the cementless Oxford UKA group [OR = 2.22, 95% CI (1.40,3.53)]. However, no significant difference was observed between the two groups in terms of reoperation rate, five-year prosthesis survival rate, and complication rate. The findings indicated that, in comparison to cemented Oxford UKA, cementless Oxford UKA resulted in a reduction in surgical time, an improvement in knee OKS score, KSS clinical score, and KSS functional score, and a decrease in the incidence of periprosthetic radiolucent lines and the rate of revisions.

The effect of high tibial osteotomy and unicompartmental knee arthroplasty on patellofemoral joint in young patients with medial knee arthrosis.

Osteoarthritis of the knee is a debilitating disease. In most cases, only the medial compartments are affected. High tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) are the two main procedures commonly used in the surgical treatment of unicompartmental knee osteoarthritis patients not responding to conservative treatment. The aim of our study was to compare UKA and biplanar medial open-wedge HTO in terms of patellofemoral changes and functional score in patients under 60 years of age with medial compartment arthrosis. A retrospective study. A total of 79 patients (37 HTO, 42 UKA) who received one of the two treatments in a single center were examined preoperatively and at a single postoperative follow-up. Posterior tibial slope, lateral patellofemoral angle (LPFA), Q-angle, patellar height, Cincinnati Rating System and Knee Injury and Osteoarthritis Outcome Score (KOOS) functional scores were evaluated in all patients preoperatively and at the 6-month follow-up examination. Insall-Salvati ratio remained stable in the HTO group, while there was a minor decrease in the UKA group and the changes between the groups were not statistically significant. Caton-Deschamps ratio increased in the UKA group and decreased in the HTO group, and this change was statistically significant (p < 0.001). LPFA did not change in the UKA group in the postoperative period, while it increased in the HTO group (p < 0.001). Changes in Q angle and Cincinnati Rating System scores were statistically similar between the UKA and HTO groups (p = 0.827 and p = 0.340). In our study, biplanar medial open-wedge HTO and UKA performed with appropriate surgical technique had no negative effect on patellofemoral joint. In patients under 60 years of age with medial compartment osteoarthritis of the knee, both surgical treatments can be performed with appropriate patient selection.

Comparison of Trends and Complications of Unicompartmental Knee Arthroplasty Versus Periarticular Knee Osteotomy Among ABOS Part II Oral Examination Candidates.

While unicompartmental knee arthroplasty (UKA) and osteotomy procedures are commonly used to treat knee osteoarthritis, the differences in complication profiles between procedures are still poorly understood. The purpose of this study was to assess the trends and complication rates of UKA and periarticular knee osteotomy for knee osteoarthritis among newly trained surgeons by using the American Board of Orthopaedic Surgery (ABOS) Part II Oral Examination Case List database. It was hypothesized that more adult reconstruction fellowship-trained surgeons would perform UKA, while more sports medicine fellowship-trained surgeons would perform osteotomy, and that both procedures would have low rates of complications. Cross-sectional study; Level of evidence, 3. The ABOS database was queried for patients who underwent UKA, high tibial osteotomy, and distal femoral osteotomy procedures in examination years 2011 to 2021. Patient characteristics, surgeon fellowship training history, surgeon-reported postoperative complications, and readmission and reoperation rates were recorded. Comparisons between the UKA and osteotomy groups were performed using independent t tests and chi-square tests. There were 2524 patients in the UKA group and 270 patients in the osteotomy group. The majority of newly trained surgeons performing UKA (70.5%) had fellowship training in adult reconstruction, while the majority of those performing osteotomy (57.8%) had fellowship training in sports medicine (P < .001). The incidence of UKA and osteotomy increased during the study period (18.8 UKAs and 1.8 osteotomies performed per 10,000 cases in 2011 vs 39.5 UKAs and 4.2 osteotomies performed per 10,000 cases in 2021). Rates were significantly higher for osteotomy compared with UKA regarding anesthetic complications (2.2% vs 0.6%; P = .015), surgical complications (23.7% vs 7.3%; P < .001), reoperation (5.2% vs 1.9%; P = .002), and infection (6.7% vs 1.4%; P < .001). There were no significant differences in rates of medical complication, readmission, deep vein thrombosis, pulmonary embolism, or stiffness/arthrofibrosis. Among newly trained surgeons taking the ABOS Part II Oral Examination, the incidence of UKA and periarticular knee osteotomy increased over the past decade. Compared with UKA, complication rates were higher after osteotomy, with an overall surgical complication rate of 23.7%.

High tibial osteotomy versus unicompartmental knee arthroplasty in advanced medial compartmental knee arthrosis: A comparative study with propensity score matched analysis

BackgroundIsolated knee medial compartmental osteoarthritis(MOA) can be treated with High Tibial Osteotomy (HTO) or Unicompartmental Knee Arthroplasty (UKA).This study aims to describe and compare outcomes of HTO and UKA in patients with isolated severe MOA. The authors hypothesized that similar outcomes can be achieved. MethodsData was collected prospectively of HTOs and UKAs performed between January-2016 and April-2021 by a knee surgeon. Oxford Knee Score (OKS), Knee Society Knee Score (KSKS) and Function Score (KSFS) were collected pre-operatively, six-months and two-years post-surgery. OA severity was graded on pre-operative radiograph. Medial Proximal Tibia Angle (MPTA), Lateral Distal Femoral Angle (LDFA), Joint Line Convergence Angle (JLCA) and Hip-Knee-Ankle Angle (HKAA), were measured on full-length radiograph.47 HTO and 74 UKA were included. Propensity score matching was performed, accounting for preoperative scores, age, gender and body mass index (BMI), before statistical analysis. Level of significance was set at 0.05. ResultsBoth groups were similar in age(56.42 vs 58.57, p = 0.067), BMI(29.82 vs 29.09, p = 0.484), gender distribution (p = 0.663) and laterality (p = 0.836).Pre-operatively, both groups were similar in clinical scores and lower limb alignment. On follow-up, both groups achieved similar improvements in clinical scores. However, the HTO group reported poorer extension at 6-months (7.91° vs 4.80°, p = 0.013) and 2-years (5.57° vs 3.24°, p = 0.018).Three cases of hinge fracture and six cases of implant removal occurred in the HTO group. One case of tibial fracture occurred in the UKA group. ConclusionsIn severe MOA, similar outcomes were achieved with HTO and UKA at two years.

Unicompartmental knee arthroplasty vs high tibial osteotomy for knee osteoarthritis: A comparison of clinical and radiological outcomes.

Unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) are well-established operative interventions in the treatment of knee osteoarthritis. However, which intervention is more beneficial to patients with knee osteoarthritis remains unknown and a topic of much debate. Simultaneously, there is a paucity of research assessing the relationship between radiographic parameters of knee joint alignment and patient-reported clinical outcomes, preoperatively and following HTO or UKA. To compare UKAs and HTOs as interventions for medial-compartment knee osteoarthritis: Examining differences in clinical outcome and investigating the relationship of joint alignment with respect to this. This longitudinal observational study assessed a total of 42 patients that had undergone UKA (n = 23) and HTO (n = 19) to treat medial compartment knee osteoarthritis. Patient-reported outcome measures (PROMs) were collected to evaluate clinical outcome. These included two disease-specific (Knee Injury and Osteoarthritis Outcome Score, Oxford Knee Score) and two generic (EQ-5D-5L, Short Form-12) PROMs. The radiographic parameters of knee alignment assessed were the: Hip-knee-ankle angle, mechanical axis deviation and angle of Mikulicz line. Statistical analyses demonstrated significant (P < 0.001), preoperative to postoperative, improvements in the PROM scores of both groups. There were, however, no significant inter-group differences in the postoperative PROM scores of the UKA and HTO group. Several significant correlations associated a more distolaterally angled Mikulicz line with worse knee function and overall health preoperatively (P < 0.05). Postoperatively, two clusters of significant correlations were observed between the disease-specific PROM scores and knee joint alignment parameters (hip-knee-ankle angle, mechanical axis deviation) within the HTO group; yet no such associations were observed within the UKA group. UKAs and HTOs are both efficacious operations that provide a comparable degree of clinical benefit to patients with medial compartment knee osteoarthritis. Clinical outcome has a limited association with radiographic parameters of knee joint alignment postoperatively; however, a more distolaterally angled Mikulicz line appears associated with worse knee function/health-related quality of life preoperatively.

Age-stratified analysis of HTO and UKA clinical effects in cross-indicated anterior medial osteoarthritis

PurposeTo compare clinical outcomes of high tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) for anterior medial osteoarthritis (AMOA) as well as offer surgical recommendations through age stratification.MethodsBetween May 2019 and May 2021, 68 cross-indicated AMOA patients were analyzed. The patients were divided into HTO and UKA groups and further into two age groups of 55–60 and 60–65 years. Additionally, general data, visual analog scale (VAS) score, and Hospital for Special Surgery knee score (HSS) were analyzed.ResultsAll the patients were followed up for 18 months. Knee joint HSS significantly improved, and VAS score decreased in both groups (P < 0.05). In the 55–60 age group, HTO showed superior knee HSS at 1 and 3 months (P < 0.05), with no significant difference at 6, 12, and 18 months. HTO had a significantly lower VAS score at one month, and the VAS scores of the two groups decreased gradually with no significant difference. In the 60–65 age group, the UKA group showed superior knee joint HSS at one month, with no significant difference at 3, 6, 12, and 18 months. The UKA group had a significantly lower VAS score at one month, and both groups’ VAS scores decreased gradually with no significant difference.ConclusionBoth methods yield satisfactory results for AMOA cross-indications, improving knee joint function. The observed recovery trends have implications for personalized surgical recommendations, guiding interventions based on age-specific considerations for optimal outcomes in anterior medial osteoarthritis cases.

Cruciate-Retaining Total Knee Arthroplasty versus Unicompartmental Knee Arthroplasty in Medial Compartmental Osteoarthritis: A Propensity Score-Matched Analysis of Early Postoperative Recovery.

Cruciate-retaining (CR) total knee arthroplasty (TKA) may provide better physiological knee kinematics, proprioception, and quadricep recovery than posterior-stabilized (PS) TKA. Therefore, we hypothesized that CR TKA with multimodal pain control may provide comparable postoperative pain and recovery as unicompartmental knee arthroplasty (UKA). This study included patients with isolated medial compartment knee osteoarthritis who underwent CR TKA and UKA. TKA and UKA patients were propensity score-matched with age and body mass index (BMI) and compared using visual analog scales (VAS) for pain scores, total amount of morphine use (TMU), knee flexion angle, straight leg raise (SLR), independent ambulation, length of hospital stay (LOS), and costs during hospitalization. After propensity score matching, 46 patients were included in the TKA and UKA groups, respectively, with no differences in demographic data. VAS at 6-72 h and TMU at 48 h after surgery were comparable between the groups. The knee flexion angle in the UKA group was significantly higher at 24 h (60.0° vs 46.6°; p<0.001) and 48 h (76.9° vs 69.1°; p = 0.021) than that in the TKA group. The SLR in the UKA group was significantly higher than that in the TKA group at 24-72 h. The UKA group ambulated significantly earlier (1.56 vs 2.13 days; p<0.001), had shorter LOS (3.68 vs 4.28 days; p<0.004) and incurred 12.43% lower costs when compared to the TKA group. Patients who underwent CR TKA with multimodal pain management did not experience more postoperative pain or morphine use than those who underwent UKA. However, UKA patients seem to experienced faster recovery and shorter LOS than CR-TKA patients during the early postoperative course. Accordingly, UKA may be considered instead of TKA for patients who are good candidates for UKA and require expedited recovery.

The unintentional effect of unicompartmental knee arthroplasty on extraarticular deformity and of high tibial osteotomy on intraarticular deformity for the treatment of anteromedial osteoarthritis.

Unicompartmental Knee Arthroplasty (UKA) and High Tibial Osteotomy (HTO) are two valid options in the treatment of Anteromedial Osteoarthritis (AMOA) of the knee with UKA being mainly performed in cases of Intraarticular deformity (IA) and HTO in cases of Extraarticular deformity (EA). The exact unintentional effect of UKA on EA deformity and HTO on IA deformity is still not well understood. The aim of this study was to assess this unintentional effect of UKA on EA and HTO on IA deformities respectively. This a single-center retrospective study in which 50 patients who underwent UKA and 50 patients who underwent medial opening wedge HTO (MWOHTO) for the treatment of AMOA were included. Overall, 35 males and 15 females underwent HTO with a mean age of 44.3 ± 11.2 years while the mean age of the UKA group was 71.8 ± 7.9 years in 23 males and 27 females. The radiological effect of UKA and HTO on each of the following angles: Hip-Knee-Ankle angle (HKA), Medial Proximal Tibial Angle (MPTA), mechanical Lateral Distal Femoral Angle (mLDFA) and Joint Line Convergence Angle (JLCA) on long film radiographs both pre- and postoperatively was measured. The postoperative values were compared to the preoperative values to detect the expected and unintended effects of each technique on IA and EA deformities. In the HTO group, the MPTA has changed significantly as expected from 83.1 ± 4.5 preoperatively to 88.9 ± 3.9 postoperatively (p value < 0.001) correcting the existing preoperative EA varus without overcorrection. Similarly in the UKA group, the JLCA has also changed significantly as expected to correct the IA varus from 3.8 ± 1.7 preoperatively to 0.9 ± 1 postoperatively (p value < 0.001). On the other hand, the JLCA was unintentionally changed in the HTO group from 2.6 ± 2.1 preoperatively to 1.6 ± 2.4 postoperatively (p value = 0.03) partly correcting the IA varus deformity. Similarly, the MPTA showed a significant change that occurred inadvertently in the UKA group from 84.8 ± 2.1 to 86.3 ± 1.6 postoperatively (p value < 0.001). This unintentional increase in the MPTA also partly corrected the preexisting EA varus deformity. The mLDFA did not show a significant change neither in the HTO group (p value = 0.96) nor in the UKA group (p value = 0.94). In addition to intraarticular varus correction, UKA can partly correct the extraarticular varus deformity in AMOA even when resurfacing is exclusively attempted. Additionally, intraarticular deformity can be also partially managed by HTO along with the extraarticular varus correction even without performing overcorrection.

Mid-term effects of unicompartmental knee arthroplasty combined with anterior cruciate ligament reconstruction for the medial compartment osteoarthritis with anterior cruciate ligament deficiency by proportioning with the pure medial compartment osteoarthritis

Objective: To evaluate the mid-term efficacy of one-stage unicompartmental knee arthroplasty (UKA) combined with anterior cruciate ligament (ACL) reconstruction in the treatment of medial compartment osteoarthritis (OA) with ACL deficiency. Methods: Retrospective cohort study. The clinical data of 13 patients (14 knees) who underwent UKA with ACL reconstruction for knee medial compartment OA combined with ACL deficiency in Wangjing Hospital of China Academy of Chinese Medical Sciences from January 2012 to January 2020 were retrospective analyzed. A 1∶1 proportioning study was conducted with 13 patients (14 knees) who underwent UKA due to medial compartment OA with intact ACL during the same period. The matching conditions were the same gender, age, surgical side, anesthesia method, comorbidities, and imaging lesions. There were 26 patients (28 knees) in the two groups, including 6 males (6 knees) and 20 females (22 knees), aged (58.9±4.2) years. The range of motion (ROM) and Oxford Knee Score (OKS) were used to evaluate the knee joint function at the last follow-up. The anteroposterior, lateral and axial X-ray films of the knee joint and the weight-bearing full-length X-ray films of the lower limbs were taken during follow-up. The hip knee ankle (HKA) angle, the posterior slope angle (PSA) of tibial prosthesis, and the anterior tibial translation (ATT) were recorded and compared between the two groups. The progression of lateral compartment OA, prosthesis loosening, and dislocation were evaluated. The mid-term follow-up clinical efficacy of the two surgical methods was compared, and the etiology of the patients was analyzed to verify the clinical efficacy and patient selection of one-stage UKA combined with ACL reconstruction. Results: The follow-up time of the two groups was (7.14±2.45) years. At the last follow-up, there was no significant difference in joint ROM between the combined group and the UKA group (120.90°±2.95° vs 122.29°±3.22°, P=0.260). There was no significant difference in OKS score between the two groups [(42.50±1.99) vs (43.21±2.26), P=0.380]. There was no significant difference in HKA angle and ATT distance between the two groups before operation (both P>0.05). At the last follow-up, the results were better than those before operation, and the differences were statistically significant (both P<0.05). At the last follow-up, there was no significant difference in HKA Angle between the combined group and the simple group (177.79°±1.25 ° vs 177.86°±1.29°, P=0.880). Tibial prosthesis PSA and ATT distance were not significantly different between the two groups [(4.57°±0.94° vs 4.50°±1.34°and (0.21±0.89) mm vs (0.14±1.35) mm, both P>0.05)]. There was no prosthesis loosening and obvious progression of lateral compartment OA in both groups at the last follow-up. Conclusion: For young patients with medial compartment OA secondary to ACL deficiency, UKA combined with ACL reconstruction is recommended, it can obtain good mid-term results.

Comparison of Early Complication Rates After High Tibial Osteotomy Versus Unicompartmental Knee Arthroplasty for Knee Osteoarthritis.

Although both high tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) can be utilized to treat unicompartmental osteoarthritis (OA) in select patients, the early complication rates between the 2 procedures are not well understood. Understanding of the complication profiles for both procedures would help clinicians counsel patients with unicompartmental knee OA who may be eligible for either treatment option. To compare the 30-day complication rates after HTO versus UKA for the treatment of knee OA using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Cohort study; Level of evidence, 3. NSQIP registries between 2006 and 2019 were queried using Current Procedural Terminology codes to identify patients undergoing HTO and UKA for knee OA. Patients >60 years of age were excluded. Patient demographics, preoperative comorbidities, and intraoperative data were collected. Postoperative 30-day complications, including venous thromboembolism (VTE), urinary tract infection (UTI), transfusion, surgical-site infection (SSI), and reoperations were recorded. Complication rates between treatment groups were compared using a multivariate logistic regression model adjusted for sex, age, body mass index, steroid use, respiratory status (smoking/dyspnea/chronic obstructive pulmonary disease), diabetes, and hypertension. A total of 156 patients treated with HTO and 4755 patients treated with UKA for knee OA were identified. Mean patient ages were 46 years for the HTO group and 53.4 years for the UKA group. Operative time was significantly longer in the HTO group versus the UKA group (112 minutes vs 90 minutes; P < .001). Multivariate analyses found no significant differences in VTE (1.3% vs 0.6%), UTI (0.6% vs 0.3%), transfusion (0.6% vs 0.2%), deep SSI (0.6% vs 0.1%), and reoperation (1.3% vs 1%) rates between HTO and UKA groups. The HTO group had a higher rate of superficial SSI compared with the UKA group (2.6% vs 0.6%; P = .006) (adjusted odds ratio, 4.2; 95% CI, 1.4-12.5; P = .01). There were no differences in 30-day VTE, UTI, transfusion, deep SSI, and reoperation rates for HTO versus UKA in the treatment of knee OA. HTO was associated with a higher rate of superficial SSI compared with UKA. These findings serve to guide clinicians in counseling patients regarding the early risks after HTO and UKA.

Functional improvement of unicompartmental knee arthroplasty compared with total knee arthroplasty for subchondral insufficiency fracture of the knee

Subchondral insufficiency fracture of the knee (SIFK) causes acute knee pain in adults and often requires surgical management. Unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) are the two most common surgical treatments for SIFK. While both UKA and TKA have their advantages, there is no consensus for SIFK localized on the medial compartment. We hypothesized that patients with SIFK treated with UKA would show superior patient-reported outcomes compared to those who underwent TKA. A total of 90 patients with SIFK located medially were included in the TKA (n = 45) and UKA (n = 45) groups. Size of SIFK lesions were measured on MR images. Patient reported outcomes in the form of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Hospital Special Surgery (HSS) scores, and Knee Society Scores (KSS) were assessed preoperatively, postoperative 6, 12 months, and at the final follow-up. There were no differences in the size of the SIFK lesion between two groups. At 6 months, WOMAC score was better in the UKA group than the TKA group (p < .01). Both groups had a significant improvement in WOMAC, HSS, and KSS scores at the final follow-up compared to preoperative scores. The UKA group had better range of motion of the knee preoperatively and postoperatively than the TKA group (p < .01 and p < .01). UKA group showed a higher relative risk than the TKA group in terms of complications (RR = 3.0) but with no statistical significance (P = 0.31). Unicompartmental arthroplasty and total joint arthroplasty can produce successful outcomes in patients with SIFK with proper patient selection, regardless of the size of SIFK lesion.

The joint line convergence angle (JLCA) correlates with intra-articular arthritis.

Knees with unicompartmental varus osteoarthritis (OA) usually display a combination of tibiofemoral bony deformity and increased joint line convergence angle (JLCA). The JLCA is a product of intra-articular deformity and lateral soft tissue laxity. This study aims to define the correlation between the JLCA and progression of OA. A retrospective radiological analysis of 501 patients, who underwent either high tibial osteotomy (HTO) or unicompartmental knee arthroplasty (UKA), was performed. The preoperative OA grade was reported based on the Ahlbäck and the Kellgren-Lawrence (KL). The hip-knee-ankle angle (HKA), the medial proximal tibial angle (MPTA), the mechanical lateral distal femoral angle (mLDFA) and the joint line convergence angle (JLCA) were recorded. The primary outcome was the relationship between the JLCA values and the OA grade. The secondary outcomes were comparing the JLCA and other alignment parameter values between HTO and UKA groups. A total of 501 (59.3% females n = 297) cases were included, comprising 293 cases of HTO and 208 cases of UKA. Patients had a mean age of 57.63 ± 8.97 years, a mean BMI of 28.37 ± 7.39 kg/m2. Patients with Ahlbäck grade 2 represented 49.3% of all patients (n = 247) and patients with KL grade 3 represented 54.7% of all patients (n = 274). A high JLCA was observed in both groups. The reported mean JLCA in the UKA group was 3.69 ± 2.1°, and in the HTO group was 2.93 ± 1.82. There was a significant association between the increase in the JLCA and the progression of OA based on both the Ahlbäck and KL grades (both p values < 0.001). The mean JLCA in patients with Ahlbäck grades 1 and 4 was 1.48 ± 1.32°, and 7 ± 0.93°, respectively. The mean JLCA in patients with KL grades 1 and 4 was 1.77 ± 1.42°, and 4.89 ± 1.73°, respectively. The mean recorded preoperative HKA angle in the UKA group was 175.06 ± 3.08°, and in the HTO group was 173.26 ± 3.02°, whereas the mean MPTA was 88.63 ± 1.72° for the UKA group and 89.31 ± 2.29° for the HTO group. The JLCA progressively increases with osteoarthritis progression in patients with unicompartmental varus knee osteoarthritis. The JLCA can potentially be used as a grading parameter for osteoarthritis progression akin to Ahlbäck and Kellgren-Lawrence grading systems.

Unicompartmental knee arthroplasties: does the type of tibial component selected influence implant survival?

Few information has been published on the survival of unicompartmental knee arthroplasty (UKA) and fixed-bearing tibial components. The aim of this study is to analyze if UKA survival varies according to UKA model used and to analyze the possible risk factors for UKA revision. A retrospective study analyzing 301 UKAs (ACCURIS, all-polyethylene tibial component, 152; Triathlon PKR, metal-backed tibial component, 149) was performed. Demographic parameters as well as implant survival and cause of prosthetic revision were analyzed. The Kaplan-Meier survival analysis, the log-rank test and the Cox multiple regression were used for the analysis. Average follow-up was 8.1 ± 3.08-years. Average age was 68.1 ± 8.6-years; 70.4% of subjects were women. The ACCURIS UKA group had a UKA revision rate higher compared to the Triathlon PKR group (16/152, 10.6% vs 5/149, 3.4%, respectively; p < 0.001). The main cause of prosthetic revision was aseptic loosening (5/21, 23.8%). All aseptic loosening cases and tibial component collapse were reported with the ACCURIS UKA group. Overall UKA survival was 98.01% (95% CI 95.62-99.1) at 1-year, 94.27% (95% CI 90.95-96.4) at 5-years and 92.38% (95% CI 88.48-94.99) at 10-years' follow-up. There were no differences in the Kaplan-Meier survival curves regarding operated side or affected tibiofemoral compartment (log-rank test = 0.614 and 0.763, respectively). However, Kaplan-Meier survival curve according to UKA model used was different (log-rank test = 0.033). The metal-backed component appeared to be a protector factor for UKA revision when adjusted for age, sex, operated side, and affected tibiofemoral compartment (Hazard Ratio 0.32, p = 0.031). Fixed-bearing UKAs showed excellent mid- and long-term survival rates. Aseptic loosening is the main cause of implant failure. PKR group (metal-backed component) seem to be a protector factor to UKA revision when it was compared with ACCURIS UKA group (all-polyethylene tibial component).

Favorable clinical outcomes of simultaneous ACL reconstruction and UKA or HTO: A systematic surveillance

PurposeOutcomes after combination of anterior cruciate ligament (ACL) reconstruction (ACLR) with unicompartmental knee arthroplasty (UKA) or high tibial osteotomy (HTO) have been widely reported, but previous systematic reviews have included articles published before 2000 and do not necessarily reflect recent trends. We conducted a thorough investigation to address (1): What are the recent surgical trends in simultaneous ACLR and UKA or HTO? and (2) What are the issues in these surgeries? based on a comprehensive systematic analysis. MethodsA systematic surveillance was performed in accordance with the PRISMA guideline. The inclusion criteria were as follows: simultaneous ACLR and UKA or HTO for medial osteoarthritis (OA) with ACL deficiency; clinical outcomes and complications recorded; publication date after 2000.A total of 1466 potentially relevant articles were identified; after exclusions, 31 articles that included 744 knees were analyzed. Fourteen articles included 330 knees underwent simultaneous ACLR and UKA (UKA group) and 17 articles included 414 knees underwent simultaneous ACLR and HTO (HTO group). ResultsOverall, complications were found in 14 knees (4.2%) in the UKA group and 47 knees (11.3%) in the HTO group. Re-rupture of the ACL was observed in only the HTO group (6 knees: 1.4%). Revision to TKA occurred in 8 knees (2.4%) in the UKA group and 1 knee (0.2%) in the HTO group. No standardized outcome measures for clinical assessment were used for all studies. ConclusionThe systematic surveillance of studies published since 2000 on the outcomes and complications of simultaneous ACLR and UKA or HTO for medial OA with ACL deficiency indicates an increasing number of reports on simultaneous ACLR and HTO or UKA in recent years. Favorable clinical results were achieved in both treatment groups.

Comparison of joint awareness after total knee arthroplasty, medial unicompartmental knee arthroplasty, and high tibial osteotomy: a retrospective study

IntroductionThis study aimed to compare the Forgotten Joint Score-12(FJS) outcomes and the minimum clinically important difference (MCID) of the FJS after high tibial osteotomy (HTO), unicompartmental knee arthroplasty (UKA), and total knee arthroplasty (TKA) with short-term follow-up (at least 2 years). Another objective of the study is to investigate the factors influencing FJS. It is hypothesized that there are differences in FJS outcomes among the three procedures.MethodsPatients who underwent HTO, UKA, and TKA from January 2016 to December 2020 and were followed up for a minimum of 2 years were included in the study. The FJS were analyses from a cohort of people who submitted data to two years. The preoperative and postoperative clinical outcomes were compared and evaluated the patient-related factor. The FJS scores were predicted using multiple linear regression analysis. Additionally, Patient's Joint Perception (PJP) questions were used as anchors to determine the achievement of the forgotten joint, and FJS MCID were calculated using the receiver operating characteristic curve (ROC).ResultsThree hundred eighty-nine patients were included in the final study, and there were 111 patients in HTO groups,128patients in UKA groups, and 150 patients in TKA groups. The mean follow-up was 47.0 months. There was a significant difference in the total FJS, between the HTO, UKA, and TKA groups (FJS:59.38 ± 7.25, 66.69 ± 7.44 and 56.90 ± 6.85, p < 0.001. We found the MCID of the FJS of HTO, UKA, and TKA were 63.54, 69.79, and 61.45, respectively. In multiple linear regression, younger age, and higher FS were significant predictors of better FJS.ConclusionMedial UKA demonstrated lower patient awareness in comparison to HTO and TKA, as assessed by the FJS. Younger age and higher FS were identified as significant predictors of improved FJS, providing valuable guidance for surgical decision-making.

Unicompartmental Knee Arthroplasty versus Total Knee Arthroplasty in Treatment of Unicompartmental Knee Osteoarthritis

Objectives This is a systematic review conducted to compare the outcomes between unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). Material and Methods Collection of data from different websites in the period from 2010 to May 2021 that studied UKA or TKA in treatment of knee osteoarthritis (OA). Comparison was made between the two techniques was performed of 12 literatures according to the study criteria and the PRESMA figure. Results There is no difference in age between the two techniques, however, there is a significant difference in gender and BMI (P &amp;lt; 0.05). The mean follow-up period of the patients was 4.14 ± 3.05 years and 3.94 ± 2.65 years in UKA and TKA groups, respectively. There is good improvement of VAS, KSS, OKS, KSS, WOMAC, ROM postoperatively regarding both techniques.

Unicompartmental Knee Arthroplasty Provides Superior Clinical and Radiological Outcomes Compared to High Tibial Osteotomy at a Follow-Up of 5-8 Years.

Knee Osteoarthritis (OA) is a debilitating disease. Initially, the medial compartments are affected in most cases. For this pathology, joint preservation is preferable. Two surgical procedures aim to meet this goal: high-tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA). The aim was to compare clinical and radiological outcomes of HTO versus UKA in patients with unicompartmental, medial OA. Retrospective case series. A total of 86 (61 UKA, 25 HTO) patients that received either treatment at a single, specialized center were assessed pre-operatively and at a single follow-up examination at 77.13 months (±8.170). The Knee Society Score (KSS), range of motion (ROM), SF36 questionnaire and the Tegner score were used. The Kellgren-Lawrence score was assessed pre- and post-surgically. Survivorship with the endpoint "revision" was assessed. The UKA group showed significantly better improvements in KSS scores for pain (p < 0.006) and function (p < 0.001). OA progression (p < 0.02) and survivorship (p < 0.018) differed, significantly favoring UKA. ROM, SF36 and Tegner score did not differ significantly. The presented mid-to long-term data suggest that UKA provides superior results in selected outcomes. Nevertheless, significant differences in the demographics of treatments indicate the challenge of comparing these two treatments.

High tibial osteotomy versus unicompartmental knee arthroplasty for Kellgren–Lawrence grade 3–4 knee osteoarthritis in younger patients: comparable improvements in patient-reported outcomes, adjusted for osteoarthritis grade and sex

PurposePrevious studies comparing high tibial osteotomy (HTO) with unicompartmental knee arthroplasty (UKA) have seldom accounted for differing patient characteristics between both groups. This study compared patient-reported outcomes (PROs) of HTO and UKA patients, adjusted for preoperative PROs, osteoarthritis grade and sex.MethodsA retrospective study was performed analysing prospectively collected PROs, namely the Oxford Knee Score (OKS) and pain/satisfaction scores, collected preoperatively and at 6 months, 12 months and 24 months postoperatively. Consecutive medial opening-wedge HTOs and medial UKAs from 2016–2019, with a preoperative Kellgren–Lawrence grade ≥ 3, aged 50–60 years, were included. Linear mixed model analyses, with the OKS over time as the primary outcome, were used.ResultsWe included 84 HTO patients (mean age 55.0 ± 3.0, 79% male, mean BMI 27.8 ± 3.4, 75% Kellgren–Lawrence grade 3) and 130 UKA patients (mean age 55.7 ± 2.8, 47% male, mean BMI 28.7 ± 4.0, 36% Kellgren–Lawrence grade 3). Response rates were ≥ 87% at all time points. Corrected for preoperative PROs, Kellgren–Lawrence grade and sex, the HTO group had a 2.5 (95% CI 1.0–4.0) points lower OKS over time than the UKA group (p = 0.001). The Numeric Rating Scale scores (NRS; 0–10) for pain at rest and during activity were higher (p < 0.01) in the HTO group. The EQ-5D-descriptive system (p < 0.01), NRS satisfaction (p < 0.01), anchor function and pain scores (p < 0.01) were lower over time in the HTO group.ConclusionUKA patients had better OKS scores, pain and satisfaction scores over time than HTO patients. However, the observed differences were below their established minimal clinically important differences. Therefore, from the patients’ perspective, HTO did not appear to be inferior to UKA under the indications outlined in this study.Level of evidence Level IV.

What is the difference in proprioception between single condylar arthroplasty and high tibial osteotomy? a comparative study on both knees of the same patient

ObjectiveThis study aims to investigate the efficacy and outcomes of different surgical procedures, namely unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO), for the treatment of bilateral medial compartment knee osteoarthritis in the same patient. The joint awareness and function of these two surgical methods were evaluated.MethodsA total of 15 patients with bilateral medial compartment knee osteoarthritis who underwent either UKA or HTO between 2012 and 2020 were included in the study. Patient data, including age, gender, body mass index and length of hospital stay, were collected. Pre- and post-operative measurements were conducted, including tibiofemoral angle, tibial plateau posterior inclination angle, proximal tibial medial angle, distance from mechanical axis to knee joint center, hip-knee-ankle angle, pre- and post-operative knee joint scores, knee joint range of motion, and FIS-12 scores at 3, 6, 12, and 24 months postoperatively. The latest follow-up was used for evaluating the outcomes of osteoarthritis treatment. Normality of continuous variables was assessed using the Shapiro–Wilk test. Between-group comparisons were performed using the paired sample t-test or Wilcoxon rank-sum test. Repeated measures analysis of variance was utilized to analyze FJS-12 measurements at different time points, and the correlation between FJS-12 and postoperative clinical results was examined using Pearson's correlation coefficient. Statistical significance was set at P < 0.05.ResultsSignificant differences were observed in FJS between the UKA and HTO groups at 3 and 6 months postoperatively, but no significant difference was found at 1 and 2 years postoperatively. FJS in the UKA group demonstrated a significant increase from 3 to 6 months postoperatively, but no significant difference was observed from 6 to 24 months postoperatively. In contrast, FJS in the HTO group showed a significant increase from 3 to 24 months postoperatively.ConclusionsPatients who underwent UKA exhibited superior joint awareness compared to those who underwent HTO during the early postoperative period. Furthermore, the rate of joint awareness in UKA patients was faster than in HTO patients.