Forgotten Joint Score Research Articles

Robotic-Assisted Total Knee Arthroplasty Results in Shorter Navigation Working Time With Similar Clinical Outcomes Compared to Computer-Navigated Total Knee Arthroplasty

BackgroundEarly clinical data are important in the appraisal of newly introduced robotic-assisted surgery (RAS) systems in total knee arthroplasty (TKA). However, there are few studies to date comparing 1-year clinical outcomes between RAS and computer-assisted navigation (CAS), the forerunner in reducing alignment outliers. The aim of this study was to determine if there was a difference between these two groups in early clinical outcomes, including functional outcome and patient-reported outcome measures (PROMs). MethodsA total of 158 propensity score-matched patients who underwent primary TKA with either CAS or RAS were retrospectively analyzed. Perioperative outcomes (navigation time, length of stay, complications, readmissions, transfusions, and technical failure), as well as functional outcome measures (range of motion, sit to stand test, timed-up-and-go test, single-leg stance test, calf raises, and step count), and PROMs (Oxford Knee Score, Knee Injury and Osteoarthritis Outcome Score, 12-item Short Form Survey, Forgotten Joint Score-12, and satisfaction) were compared between those who underwent CAS and those who underwent RAS. ResultsNavigation time was shorter in the RAS group compared to the CAS group (mean difference, 15.4 minutes; P < 0.001). There were 2 complications reported in the CAS group (one patellar clunk, one periprosthetic joint infection), but none in the RAS group. There were no other readmissions, transfusions, or technical failures in either group. Postoperatively, there were no clinical differences in function between groups. Clinically meaningful improvement in PROMs was observed in both groups, with no differences. ConclusionsThe use of RAS resulted in shorter navigation time compared to CAS in TKA. No other differences were observed in early clinical outcomes between patients who underwent RAS and CAS.

No differences in clinical and radiographic outcomes between standard offset and high offset short cementless stems.

To compare clinical and radiographic outcomes of total hip arthroplasty (THA) using standard offset versus high offset short cementless stems. We reviewed a consecutive series of 204 primary THAs performed over 5years using a short cementless collared stem. At a minimum follow-up of 2years, 6 patients had deceased, 6 were not evaluated radiographically and, 2 were lost to follow-up. This left a final cohort of 190 hips, of which 72 had received a standard offset stem and 118 had received a high offset stem. Outcomes collected included: Oxford hip score (OHS), forgotten joint score (FJS), canalfill ratio (CFR),canal-bone ratio (CBR), stem subsidence (≥ 3mm), stem misalignment (> 5°), radiolucent lines (≥ 2mm), cortical hypertrophy, and calcar modifications. There were no significant differences in postoperative clinical and radiographic outcomes between the standard offset and high offset groups, except for incidence of stems in varus (6% vs 17%; p = 0.001). Multivariable analyses revealed that OHS was significantly worse for patients of greater age (β = 0.1; p = 0.001), higher BMI (β = 0.2; p = 0.018), or with inflammatory arthropathy (β = 4.7; p = 0.005); while FJS was significantly worse for patients with higher BMI (β = -0.7; p = 0.003); and cortical hypertrophy was significantly associated with CBR (OR > 100; p = 0.008). There were little to no differences in clinical or radiographic outcomes of THA performed using standard offset versus high offset short cementless stems. Although high offset stems are more frequently aligned in varus, while cortical hypertrophy occurs in wider intramedullary canals.

The Wagner Cone Stem for Atypical Femoral Anatomy in Total Hip Arthroplasty: A Report of 320 Cases with Minimum 5-Year Follow-up.

The Wagner Cone Prosthesis was designed to address complex femoral deformities during total hip arthroplasty (THA), but its mid-term component survivorship and functional outcomes remain undetermined. The objectives of this study were to determine the implant survivorship, patient satisfaction, functional outcomes, osseointegration as seen radiographically, implant subsidence, and complications of THA using the Wagner Cone Prosthesis stem at intermediate-term follow-up. This study involved 302 patients with proximal femoral deformities, including developmental hip dysplasia and Legg-Calvé-Perthes disease, who underwent a total of 320 primary THAs using the Wagner Cone Prosthesis. The average age at the time of surgery was 49.4 ± 14.5 years (range, 18.8 to 85.6 years). Patient satisfaction was recorded using a self-administered questionnaire assessing satisfaction in 4 domains. The University of California at Los Angeles (UCLA) activity score, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Oxford Hip Score (OHS), the Forgotten Joint Score (FJS), radiographic outcomes, and complications were recorded. The mean follow-up time was 10.1 years (range, 5.2 to 15.5 years). Survivorship of the Wagner Cone Prosthesis was 98.7% (95% confidence interval [CI]: 97.2% to 100%) with stem revision as the end point and 95.8% (95% CI: 93.5% to 98.2%) with reoperation for any reason as the end point at 10 years postoperatively. In total, 3 stems were revised: 2 for infection and 1 for chronic hip dislocation. The median patient satisfaction score was 95 (interquartile range [IQR], 80 to 100), median UCLA score was 6 (IQR, 6 to 7), median WOMAC score was 18 (IQR, 16 to 22), median OHS was 40 (IQR, 36 to 47), and median FJS was 80 (IQR, 76 to 88) at the time of final follow-up. All Wagner Cone stems that were not revised showed radiographic evidence of osseointegration, with a mean stem subsidence of 0.9 ± 0.8 mm at the most recent follow-up. The use of the Wagner Cone Prosthesis stem in patients with complex femoral anatomy undergoing primary THA is associated with excellent component survivorship, high levels of patient satisfaction, good functional outcomes, and reliable osseointegration with minimal stem subsidence as seen on radiographs at intermediate-term follow-up. Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

THE FIRST 200 CERAMIC-ON-CERAMIC HIP RESURFACING IMPLANTS AT MINIMUM TWO-YEAR FOLLOW-UP

Hip resurfacing arthroplasty (HRA) is a bone conserving alternative to total hip arthroplasty. We present the early 2-year clinical and radiographic follow-up of a novel ceramic-on-ceramic (CoC) HRA in an international multi-centric cohort.Patients undergoing HRA between September 2018 and January 2021 were prospectively included. Patient-reported outcome measures (PROMS) in the form of the Forgotten Joint Score (FJS), HOOS Jr, WOMAC, Oxford Hip Score (OHS) and UCLA Activity Score were collected preoperatively and at 1- and 2-years post-operation. Serial radiographs were assessed for migration, component alignment, evidence of osteolysis/loosening and heterotopic ossification formation.200 patients were identified to have reached 2-year follow-up. Of these, 185 completed PROMS follow-up at 2 years. There was significant improvement in HOOS (p&lt; 0.001) and OHS (p&lt; 0.001) and FJS (p&lt; 0.001) between the pre-operative and 2-year outcomes. Patients reported improved pain (p&lt;0.001), function (p&lt;0.001) and reduced stiffness (p&lt;0.001) as measured by the WOMAC score. Patients had improved activity scores on the UCLA Active Score (P&lt;0.001) with 53% reporting return to impact activity at 2 years. There was no osteolysis and the mean acetabular cup inclination angle was 41deg and the femoral component shaft angle was 137deg. No fractures were reported over but there was one sciatic nerve palsy with partial recovery. Two patients were revised; one at 3 months for pain due to a misdiagnosed back problem and another at 33 months for loosening of the acetabular component with delamination of the titanium ingrowth surface.CoC resurfacing at 2-years post-operation demonstrate promising results with satisfactory PROMS.

PREOPERATIVE ACTIVITY LEVEL IN PATIENTS WHO UNDERWENT TOTAL HIP ARTHROPLASTY HAS A DISTINCT IMPACT ON POSTOPERATIVE RECOVERY PROCESS AND FJS-12

Recently, some smart media devices including portable accelerometers have been used to measure objective physical activity (OPA) after total hip arthroplasty (THA). The aim of this study was to longitudinally assess OPA changes in patients who underwent THA using a compact triaxial accelerometer and to investigate the impact of this recovery process on patient-reported outcomes.This prospective cohort study involved 163 consecutive patients who had unilateral osteoarthritis of the hip and were followed up for 12 months after THA. There were 132 women and 31 men with average age of 66 years. OPA was measured using a compact triaxial accelerometer preoperatively and at 1, 3, 6, and 12 months postoperatively. This study investigated the recovery process of OPA in four patient groups classified by the median of age and preoperative activity levels (younger and higher activity (YH), younger and lower activity (YL), older and higher activity (OH), and older and lower activity (OL)), and examined its impact on patient-reported outcomes, including forgotten joint score-12 (FJS-12).The target period for regaining preoperative activity levels was approximately 3 months for patients with lower preoperative activity, and about 6 months for those with higher preoperative activity. The OPA at 12 months postoperatively was higher in the patients with higher preoperative activity levels than in those with lower preoperative activity levels. In patients with higher preoperative activity levels, FJS-12 scores significantly increased between 6 and 12 months postoperatively (p=0.018). FJS-12 at 12 months postoperatively was best in YH (81.7±18.9), followed by YL (73.5±22.9), OH (73.2±17.4), and OL (66.3±21.8).Differences in the recovery process of postoperative activity levels impacted the duration required for improvement in FJS-12 scores. These results can serve as indicators for setting activity goals in patients undergoing THA.

Assessment of functional and radiological outcomes of suprapatellar and infrapatellar approaches of tibial nailing in patients with tibial shaft fracture: A randomized control study

BackgroundThe study aimed to assess functional and radiological outcomes of the suprapatellar approach (SPA) and infrapatellar approaches (IPA) of tibial nailing in patients with closed tibia shaft fractures. MethodAfter Institutional Ethical Committee (IEC) and Clinical Trials Registry- India (CTRI) approval, patients with Orthopaedic Trauma Association (OTA) fracture type 42 were enrolled from August 2021 and August 2022 at a level I trauma centre and randomized to SPA and IPA with informed consent. Demographics, American Society of Anaesthesiologists (ASA) physical grading, intraoperative fluoroscopy time, operative duration, bleeding, postoperative radiographic alignment, and union were compared among both approaches. Functional parameters like Lysholm knee score, Anterior knee pain (AKP), Visual Analog Scale (VAS) Score upon kneeling, Knee Injury and Osteoarthritis outcome score (KOOS), KOOS Patellofemoral score (KOOS PF), EuroQol (EQ5D5L), Forgotten joint score (FJS), Range of motion (ROM) of knee and any complications were assessed at 3,6 and 12 months postoperatively. ResultsPer protocol analysis of 50 patients (25 SPA, 25 IPA) done at the end of the study. SPA group had significantly lesser fluoroscopy time (91.28 ± 12.40s vs. 105.36 ± 9.23s, p < 0.001) and operative duration (mins) (123.80 ± 24.25 vs. 130.00 ± 18.20, p < 0.001) than IPA. No significant differences were noted in Lysholm knee score at three months (p = 0.094), six months (p = 0.406), and 12 months (p = 0.071). The SPA group showed significantly lower VAS Score upon kneeling at six months (p < 0.0001). Similarly, KOOS (p < 0.001), KOOS PF (p = 0.01), and EQ 5D5L (p = 0.03) were significantly better in the SPA group at six months postoperatively. Lower Coronal translation was found in SPA [0 (0–1.8) vs. 1.4 (0.9–1.8), p = 0.010]. Whereas, IPA had higher range of flexion at 3 months [130.0 (129.0–135.0) vs 123.1 (120.0–130.5), p = 0.047]. However, no significant differences were noted in blood loss, AKP, FJS, EQ-VAS, coronal angulation, sagittal malalignment, time to union, return to work and postoperative complications among the groups. ConclusionSPA has lesser surgery time, more straightforward anatomic fracture reduction, better fracture alignment, lesser radiation exposure for both patients and surgeons, quicker recovery time, and promotes early kneeling activities with similar long-term functional outcomes and union rates, and can be considered in routine clinical practice than conventional IPA.

Effects of preoperative valgus deformity in patients undergoing neutrally aligned total knee arthroplasty: A retrospective cohort study with a minimum five-year follow-up.

This study aimed to investigate the relationship between the severity of preoperative valgus deformity and clinical outcomes of neutrally aligned total knee arthroplasty (TKA). A total of 376 knees with valgus deformity who underwent TKA from January 2006 to March 2014 were retrospectively screened, and 287 knees (242 patients; 32 males, 210 females; mean age: 64.5±8.8 years; range, 35 to 83 years) aligned neutrally after the operation were included. Patients were divided into four groups based on the preoperative hip-knee-ankle (HKA): mild (0°< HKA ≤5°, n=94), moderate (5°< HKA ≤10°, n=74), severe (10°< HKA ≤15°, n=75), and very severe (HKA >15°, n=44) groups. Range of motion (ROM), Knee Society Score (KSS), Visual Analog Scale (VAS) dynamic pain scores, and Forgotten Joint Score (FJS) were evaluated. Mechanical failures were recorded to assess prosthesis survival. A survival rate analysis was performed using Kaplan-Meier survival analysis. The degree of preoperative valgus deformity did not have a significant impact on the postoperative ROM, KSS, VAS dynamic pain scores, or FJS at the last follow-up. There were no significant differences in cumulative survival rates of neutrally aligned TKAs at 10 years between the four groups (p=0.513). The severity of preoperative valgus deformity did not affect the clinical outcomes of neutrally aligned TKAs in the minimum five-year follow-up. Additionally, it did not impact the survival rates of neutrally aligned TKAs over 10 years.

No Difference in 10-year Clinical or Radiographic Outcomes Between Kinematic and Mechanical Alignment in TKA: A Randomized Trial.

There is continuing debate about the ideal philosophy for component alignment in TKA. However, there are limited long-term functional and radiographic data on randomized comparisons of kinematic alignment versus mechanical alignment. We present the 10-year follow-up findings of a single-center, multisurgeon randomized controlled trial (RCT) comparing these two alignment philosophies in terms of the following questions: (1) Is there a difference in PROM scores? (2) Is there a difference in survivorship free from revision or reoperation for any cause? (3) Is there a difference in survivorship free from radiographic loosening? Ninety-nine patients undergoing primary TKA for osteoarthritis were randomized to either the mechanical alignment (n = 50) or kinematic alignment (n = 49) group. Eligibility for the study was patients undergoing unilateral TKA for osteoarthritis who were suitable for a cruciate-retaining TKA and could undergo MRI. Patients who had previous osteotomy, coronal alignment > 15° from neutral, a fixed flexion deformity > 15°, or instability whereby constrained components were being considered were excluded. Computer navigation was used in the mechanical alignment group, and patient-specific cutting blocks were used in the kinematic alignment group. At 10 years, 86% (43) of the patients in the mechanical alignment group and 80% (39) in the kinematic alignment group were available for follow-up performed as a per-protocol analysis. The PROMs that we assessed included the Knee Society Score, Oxford Knee Score, WOMAC, Forgotten Joint Score, and EuroQol 5-Dimension score. Kaplan-Meier analysis was used to assess survivorship free from reoperation (any reason) and revision (change or addition of any component). A single blinded observer assessed radiographs for signs of aseptic loosening (as defined by the presence of progressive radiolucent lines in two or more zones), which was reported as survivorship free from loosening. At 10 years, there was no difference in any PROM score measured between the groups. Ten-year survivorship free from revision (components removed or added) likewise did not differ between the groups (96% [95% CI 91% to 99%] for the mechanical alignment group and 91% [95% CI 83% to 99%] for the kinematic alignment group; p = 0.38). There were two revisions in the mechanical alignment group (periprosthetic fracture, deep infection) and four in the kinematic alignment group (two secondary patella resurfacings, two deep infections). There was no statistically significant difference in reoperations for any cause between the two groups. There was no difference with regard to survivorship free from loosening on radiographic review (χ2 = 1.3; p = 0.52) (progressive radiolucent lines seen at 10 years were 0% for mechanical alignment and 3% for kinematic alignment). Like the 2-year and 5-year outcomes previously reported, 10-year follow-up for this RCT demonstrated no functional or radiographic difference in outcomes between mechanical alignment and kinematic alignment TKA. Anticipated functional benefits of kinematic alignment were not demonstrated, and revision-free survivorship at 10 years did not differ between the two groups. Given the unknown long-term impact of kinematic alignment with regard to implant position (especially tibial component varus), we must conclude that mechanical alignment remains the reference standard for TKA. We could not demonstrate any advantage to kinematic alignment at 10-year follow-up. Level I, therapeutic study.

Patients' joint perception after anterior cruciate ligament reconstruction as a reliable patient-reported outcome measure.

This study aims to evaluate and compare patients' joint perception (PJP) with other commonly employed patient-reported outcome measures (PROMs) in a cohort of patients following anterior cruciate ligament reconstruction (ACLR). A retrospective study was conducted on 108 patients who underwent ACLR between 2017 and 2021, with complete data available for visual analogue scale (VAS) pain, PJP, Forgotten Joint Score (FJS), Tegner Activity Scale, Lysholm Knee Scoring Scale, Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI), Single Assessment Numeric Evaluation (SANE), Cincinnati Knee Rating System (CKRS)and The Hospital for Special Surgery Anterior Cruciate Ligament Satisfaction Survey (HSS ACL-SS) at a mean follow-up of 3 years. Spearman's rank-order correlation was used to determine the correlations between clinical scores. A receiver operating characteristic (ROC) curve analysis was used to assess the discriminatory power of the chosen PROMs in detecting natural joint perception. Natural joint perception was defined as patients responding 'like a native or natural joint' or PJP = 1. This study hypothesized that PJP would demonstrate significant correlations with established PROMs, indicating its reliability and validity as a tool for assessing outcomes following ACLR. PJP showed significant correlations with all the reported PROMs, suggesting its potential as a valid and reliable assessment tool for evaluating ACLR outcomes. The ROC curve analysis indicated a good area under the curve for identifying natural joint perception using various PROMs. According to the PJP, nearly 20% of patients reported natural joint perception. This study evaluates PJP as a reliable tool for assessing patient outcomes following ACLR. Its significant correlation with other established PROMs underscores its potential as a valuable addition to the existing array of PROMs in ACLR. Level III.

No differences in clinical and radiographic outcomes between standard versus high offset collared stems for primary total hip arthroplasty at fiveyears follow-up.

To compare clinical and radiographic outcomes of propensity-matched patients undergoing THA using standard versus high offset stems at fiveyears. The authors retrospectively reviewed a consecutive series of primary THAs performed between 01/09/2015-31/12/2017 using a fully-hydroxyapatite coated collared stem, with either a standard (n = 365) or high (n = 110) offset. Outcomes collected included: modified Harris Hip Score (mHHS), Oxford Hip Score (OHS), Forgotten Joint Score (FJS), and radiographic measurements including limb length discrepancy (LLD), stem subsidence, and stem radiolucencies. Propensity score matching resulted in 80 hips per group. Preoperatively there were no significant differences in patient demographics, surgical data and radiographic measurements, except the standard offset group had significantly smaller femoral (40.0 ± 7.5 vs 48.4 ± 6.2, p < 0.001), acetabular (92. ± 6.3 vs 94.8 ± 7.3, p = 0.011) and global (132.0 ± 10.3 vs 143.2 ± 8.2, p < 0.001) offsets compared to the high offset group. At a minimum fiveyears follow-up, there were no significant differences in mHHS (93.2 ± 11.0 vs 93.1 ± 10.6, p = 0.553), OHS (45.1 ± 4.1 vs 45.3 ± 4.6, p = 0.623), and FJS (85.1 ± 19.3 vs 82.7 ± 23.0, p = 0.910). There were also no differences in radiographic measurements, including LLD (1.5 ± 4.8 vs 1.1 ± 3.5, p = 0.537), stem subsidence (0% vs 0%, p = 1.000), and stem radiolucencies (severe: 6% vs 1%, p = 0.152). The present matched-cohort study found no significant differences between standard versus high offset straight fully-hydroxyapatite coated collared stems for primary THA in terms of clinical and radiographic outcomes at fiveyears. These findings may suggest that uncemented collared high offset stems are not associated with an increased risk of radiolucencies and loosening compared to uncemented collared standard offset stems.

The Optimal Variation Range of Posterior Condylar Offset Associated with Positive Clinical Outcomes of Primary Total Knee Arthroplasty: A Retrospective Analysis.

Posterior condylar offset (PCO) and anterior condylar offset (ACO) exert an influence on the sagittal alignment in total knee arthroplasty (TKA). However, there is no common consensus that the variation range of posterior condylar offset (PCO) is associated with patient-reported outcome measures (PROMs) and the optimum variation range of PCO. This study aims to investigate the correlation between PCO and the PROMs of primary TKA for osteoarthritis (OA) and find out the optimal variation range of the PCO. In this study, we performed a radiographic analysis of 106 patients (112 knees) with primary TKA. Patients were divided into two cohorts (A and B) according to the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC). Correlations between the sagittal parameter and WOMAC were investigated using univariate and multivariate analysis. The receiver operating characteristic (ROC) curve was used to establish the cut-off value for the optimal variation range. We then further investigated how different variation range affects the WOMAC subscale score and forgotten-joint-score-12 (FJS-12). Univariate analysis revealed a correlation between the variation range of PCO (p < 0.01), ACO (p < 0.01) and PROMs. Multivariate analysis showed that only PCO was associated with PROMs. In the ROC graph, the cut-off value of the variation range of PCO is 2.85 mm (AUC = 0.66, Youden index = 0.26). The WOMAC functional ability score of the group outside the PCO variation range of 2.85 mm significantly increased compared to the group within the range. In this study, PCO variation was significantly associated with clinical outcomes in TKA and the optimal PCO variation range was within 2.85 mm. Maintaining the PCO variation within 2.85 mm could enhance functional recovery and patient satisfaction.

Improvements in Noise Symptoms, Forgotten Joint Scores, and Functional Outcomes With Greater Time Following Total Knee Arthroplasty

BackgroundTotal knee arthroplasty (TKA) is an impactful procedure with goals that include pain reduction and improved function, with low levels of prosthesis awareness. The purpose of this study was to determine if patients reported prosthetic noise and noise-related symptoms diminished over the course of time after TKA. MethodsThis study was a single institutional, retrospective study of patients who underwent primary unilateral TKA from 2018 to 2021. The TKAs were performed by four high-volume, fellowship-trained arthroplasty surgeons. Patients had similar baseline characteristics. Patients completed a survey consisting of four Likert scale questions related to prosthetic noise generation, the Forgotten Joint Score, and the Knee Injury and Osteoarthritis Outcome Score-Joint Replacement. Data were compared between patients who had undergone TKA one to two years earlier (N = 305) and those who had TKA three to four years prior to evaluation (N = 177). ResultsAfter more time with TKA, patients had significantly lower reports of hearing noise (31.1 versus 43.6%; P = 0.009) and feeling prosthetic noise-related symptoms (28.2 versus 40.3%; P = 0.010). Furthermore, after more time from TKA, patients had significantly higher satisfaction regarding noise-generation (65.5 versus 50.2%; P = 0.012), postoperative Knee Injury and Osteoarthritis Outcome Score-Joint Replacement scores (80.9 versus 75.9; P = 0.005), and Forgotten Joint Scores (65.4 versus 53.8; P < 0.001). ConclusionsAs more time passes after TKA, patients observe less prosthetic noise generation and have lower levels of prosthesis awareness and greater satisfaction than those who had surgery more recently. It is unclear whether these differences represent real improvement or acclimation to noise over time.

Total knee arthroplasty using a cemented single-radius, condylar-stabilized design performed without posterior cruciate ligament sacrifice.

Total knee arthroplasty (TKA) with a highly congruent condylar-stabilized (CS) articulation may be advantageous due to increased stability versus cruciate-retaining (CR) designs, while mitigating the limitations of a posterior-stabilized construct. The aim was to assess ten-year implant survival and functional outcomes of a cemented single-radius TKA with a CS insert, performed without posterior cruciate ligament sacrifice. This retrospective cohort study included consecutive patients undergoing TKA at a specialist centre in the UK between November 2010 and December 2012. Data were collected using a bespoke electronic database and cross-referenced with national arthroplasty audit data, with variables including: preoperative characteristics, intraoperative factors, complications, and mortality status. Patient-reported outcome measures (PROMs) were collected by a specialist research team at ten years post-surgery. There were 536 TKAs, of which 308/536 (57.5%) were in female patients. The mean age was 69.0 years (95% CI 45.0 to 88.0), the mean BMI was 32.2 kg/m2 (95% CI 18.9 to 50.2), and 387/536 (72.2%) survived to ten years. There were four revisions (0.7%): two deep infections (requiring debridement and implant retention), one aseptic loosening, and one haemosiderosis. Kaplan-Meier analysis demonstrated no difference in implant survival according to sex, age, or obesity status. Ten-year PROMs were available for 196/387 (50.6%) surviving patients and were excellent: mean Oxford Knee Score 34.4 (95% CI 32.7 to 36.1); mean Forgotten Joint Score (FJS) 51.2 (95% CI 16.1 to 86.3); mean EuroQol five-dimension five-level questionnaire score 69.9 (95% CI 46.8 to 93.0); 141/196 (71.9%) achieved the 22-point FJS patient-acceptable symptom state (PASS); and 156/196 (79.6%) were "very satisfied or satisfied". This is the only large study reporting ten-year implant survival and functional outcomes of TKA using a cemented single-radius design and with a CS tibial bearing construct. The findings of excellent implant survival, safety, and functional outcomes indicate that this combination is a safe and effective option in routine TKA. Further investigation of this single-radius design TKA with CS tibial bearings with well-matched patient study groups will allow further insight into the performance of these implants.

Forgotten joint score associated with prosthesis weight in cementless total hip arthroplasty: a prospective clinical study.

This prospective study aimed to investigate the influence of weight difference between implanted prosthesis and removed bone in cementless total hip arthroplasty (THA) on hip awareness and patient-reported outcomes. A total of 48 patients (56 hips) who underwent primary THA were prospectively enrolled. Implanted prosthesis and removed bone were weighed intraoperatively. Forgotten Joint Score (FJS) and Western Ontario and McMaster Universities (WOMAC) scores were obtained before and at 1 and 3 months after surgery. Patients were divided into groups A, B, and C according to the percentile of the weight difference. The mean weight difference of the implanted prosthesis and removed bone was 117.97 ± 47.35 g. A negative correlation was found among the weight differences of the three groups and 1- and 3-month postoperative FJS (correlation coefficients, -0.331 and -0.734, respectively). A positive correlation was found among the weight difference of the three groups and 3-month postoperative WOMAC (correlation coefficient, 0.403). A significant difference in 3-month postoperative FJS and WOMAC scores was found among the three groups. The mean 3-month postoperative FJS (79.00) of group C was significantly lower than that of group A (93.32) (P < 0.05). The mean WOMAC score (15.83) of group A was significantly lower than that of group C (23.67) (P < 0.05). The implanted prosthesis is larger than the removed bone in cementless THA. The weight difference is negatively correlated with hip function. The weight difference should be minimized to achieve optimal hip joint awareness.

One-day surgery is safe and effective in unicompartmental knee arthroplasty: A prospective comparative study at 1 year of follow-up.

To compare the outcomes and complications of two perioperative protocols for the management of patients who underwent medial unicompartmental knee arthroplasty (UKA): 24 h (1-day surgery [OS]) versus 72 h (enhanced recovery after surgery [ERAS]) of the length of hospital stay (LOS). In our hypothesis, the reduction of the LOS from 3 to 1 day did not influence the outcomes and complications. A total of 42 patients (21 in each group) with isolated anteromedial knee osteoarthritis and meeting specific criteria were prospectively included in the study. Clinical outcomes included Knee Society Score (KSS) and Forgotten joint score while pain evaluation was performed using a Visual Analogue Scale (VAS). Functional outcomes were assessed measuring the knee range of motion (ROM) while radiographic outcomes were evaluated measuring the amelioration of the varus deformity through the hip-knee-ankle angle (HKA). Clinical and functional outcomes did not significantly differ between the two groups. Complications occurred in 9.5% of OS and 4.7% of ERAS group patients. Significant improvements in knee ROM, VAS pain, KSS and HKA angle were observed postsurgery, with no significant differences between groups except in KSS expectations and function trends. The OS protocol is safe and effective and LOS, in a well-defined fast-track protocol, did not significantly impact clinical and functional outcomes. OS may lead to reduced hospitalisation costs and potential reductions in complications associated with prolonged stays, benefiting both patients and healthcare facilities. However, further research with larger sample sizes and longer follow-up periods is needed to confirm these findings. Early mobilisation and rehabilitation protocols are key components of successful patient recovery following UKA procedures. Level II.

Mechanically aligned total knee arthroplasty does not yield uniform outcomes across all coronal plane alignment of the knee (CPAK) phenotypes.

Patient dissatisfaction rates following total knee arthroplasty (TKA) reported in the literature reach 20%. The optimal coronal alignment is still under debate. The aim of this retrospective study was to compare clinical outcomes in different coronal plane alignment of the knee (CPAK) phenotypes undergoing mechanically aligned (MA) TKA. The hypothesis was that knees with preoperative varus arithmetic hip-knee-ankle angle (aHKA) would achieve inferior clinical outcomes after surgery compared to other aHKA categories. Additionally, another objective was to assess CPAK phenotypes distribution in the study population. A retrospective selection was made of 180 patients who underwent MA TKA from April 2021 to December 2022, with a 1-year follow-up. Coronal knee alignment was classified according to the CPAK classification. Clinical outcome evaluations were measured using the Knee Society Score (KSS), Oxford Knee Score (OKS), Short Form Survey 12and Forgotten Joint Score (FJS). Differences in clinical outcomes were considered statistically significant with a p value <0 .05. Patients with varus aHKA achieved significantly inferior outcomes at final follow-up compared to other aHKA categories in KSS pt. 1 (79.7 ± 17.2 vs. 85.6 ± 14.7; p = 0.028), OKS (39.2 ± 9.2 vs. 42.2 ± 7.2; p = 0.019) and FJS (75.4 ± 31.0 vs. 87.4 ± 22.9; p =0 .003). The most common aHKA category was the varus category (39%). The most common CPAK phenotypes were apex distal Types I (23.9%), II (22.8%)and III (13.3%). MA TKA does not yield uniform outcomes across all CPAK phenotypes. Varus aHKA category shows significantly inferior results at final follow-up. The most prevalent CPAK categories are varus aHKA and apex distal JLO, with phenotypes I, IIand III being the most common. However, their gender distribution varies significantly. Level IV.

Cementless short stem total hip arthroplasty in patients older than 75 years: is it feasible?

BackgroundIn recent years, the indication for cementless short stem total hip arthroplasty (THA) has been widened to elderly patients as they might profit by the advantages of the short-curved implant design as well. Therefore, this study was conducted to evaluate the clinical and radiological outcome of a cementless short stem in elderly patients (≥ 75 years) compared to a young control group (≤ 60 years).MethodsA retrospective cohort of 316 THAs performed between 2014 and 2017 was prospectively examined. In all patients a cementless, curved short stem and press-fit cup (Fitmore® stem; Allofit®/-S cup; both ZimmerBiomet, Warsaw, IN, USA) were implanted via a minimally-invasive anterolateral approach. Clinical and radiological outcome as well as rate of complications and revision were assessed.ResultsIn total, 292 patients have been included for analysis of complications and revisions (Øfollow-up: 4.5 years) and 208 patients for clinical and radiological outcome (Øfollow-up: 4.4 years). Complication rate was significantly increased in elderly patients (13.7% vs. 5.8%, p = 0.023), while the revision rate was increased without statistical significance (5.2% vs. 2.2%, p = 0.169). Periprosthetic fractures occurred significantly higher in the elderly patients (5.2% vs. 0.7%; p = 0.026). Both groups showed a comparable clinical outcome in the Harris Hip Score (93.7 vs. 91.9; p = 0.224), Oxford Hip Score (44.5 vs. 43.7; p = 0.350), Forgotten Joint Score (81.7 vs. 81.5; p = 0.952) and WOMAC (7.4 vs. 9.3; p = 0.334).ConclusionCementless short stem total hip arthroplasty shows a comparable clinical and radiological outcome in patients over 75 years of age compared to younger patients under 60 years of age. However, cementless shorts stem THA shows an increased rate of overall complications and periprosthetic fractures in elderly patients over 75 years of age. Cemented fixation of the femoral component should be considered in patients over 75 years of age.Level of evidenceIII Case-controlled study.Trial registrationObservational study without need for trial registration due to ICMJE criteria.

939 A Comparison of the Short-Term Outcomes Following Robotic-Assisted and Computer-Navigated Total Knee Replacements

Abstract Aim Total knee replacements (TKR) remain as one of the most effective procedures for restoring quality of life. Computer-navigated TKR (CN-TKR) have been consistently used for the last two decades whereas robotic-assisted TKR (RA-TKR) have been recently introduced into practice. The primary outcome of this study was to compare the early outcomes following RA-TKR and CN-TKR. Method This retrospective, single-centre, cohort study identified all the patients who underwent a TKR in the Golden Jubilee National Hospital by a single primary hip and knee replacement surgeon between 12th January 2021 and 22nd April 2022. Results were analysed for statistical significance. Results 111 patients underwent a TKR between January 2021 and April 2022. 26 patients underwent a RA-TKR using Stryker’s MAKO SmartRobotics and 85 patients underwent CN-TKR using B. Braun’s OrthoPilot®. Patients who had an RA-TKR were younger, with the average being 64 compared to 69. They also had a greater ROM pre-operatively, with an additional 9 degrees of movement on average. However, post-operatively there was no difference in ROM. There was no change in the mean length of stay (LOS), operation length, blood loss, Oxford score, EQ5-D score, and Forgotten Joint Score. At the 6-week follow-up, 96% of RA-TKR patients were either satisfied or very satisfied compared to 91% of CN-TKR patients. Conclusions This study found no significant difference in short-term clinical outcomes between RA-TKR and CN-TKR. However, a small sample size and a relatively short time frame in which data was collected limits this study to some extent and further research is recommended.

Robotic arm-assisted conversion of unicompartmental knee arthroplasty to total knee arthroplasty.

Robotic arm-assisted surgery offers accurate and reproducible guidance in component positioning and assessment of soft-tissue tensioning during knee arthroplasty, but the feasibility and early outcomes when using this technology for revision surgery remain unknown. The objective of this study was to compare the outcomes of robotic arm-assisted revision of unicompartmental knee arthroplasty (UKA) to total knee arthroplasty (TKA) versus primary robotic arm-assisted TKA at short-term follow-up. This prospective study included 16 patients undergoing robotic arm-assisted revision of UKA to TKA versus 35 matched patients receiving robotic arm-assisted primary TKA. In all study patients, the following data were recorded: operating time, polyethylene liner size, change in haemoglobin concentration (g/dl), length of inpatient stay, postoperative complications, and hip-knee-ankle (HKA) alignment. All procedures were performed using the principles of functional alignment. At most recent follow-up, range of motion (ROM), Forgotten Joint Score (FJS), and Oxford Knee Score (OKS) were collected. Mean follow-up time was 21 months (6 to 36). There were no differences between the two treatment groups with regard to mean change in haemoglobin concentration (p = 0.477), length of stay (LOS, p = 0.172), mean polyethylene thickness (p = 0.065), or postoperative complication rates (p = 0.295). At the most recent follow-up, the primary robotic arm-assisted TKA group had a statistically significantly improved OKS compared with the revision UKA to TKA group (44.6 (SD 2.7) vs 42.3 (SD 2.5); p = 0.004) but there was no difference in the overall ROM (p = 0.056) or FJS between the two treatment groups (86.1 (SD 9.6) vs 84.1 (4.9); p = 0.439). Robotic arm-assisted revision of UKA to TKA was associated with comparable intraoperative blood loss, early postoperative rehabilitation, functional outcomes, and complications to primary robotic TKA at short-term follow-up. Robotic arm-assisted surgery offers a safe and reproducible technique for revising failed UKA to TKA.

Large angular correction of arithmetic coronal alignment is associated with residual lateral laxity after total knee arthroplasty in varus knees for Japanese patients.

One of the most common types of coronal plane alignment of the knee (CPAK) is type I, which is characterised by varus alignment and apex distal joint line obliquity. The purpose of this study was to evaluate the association of changes in arithmetic hip-knee-ankle angle (aHKA) with both postoperative joint laxity and patient-reported outcome measures (PROMs) in patients with CPAK type I following mechanical alignment (MA) total knee arthroplasty (TKA). Of 111 consecutive knees in 92 patients with osteoarthritis who underwent primary TKA, 80 knees (72.0%) with CPAK type I phenotype preoperatively were evaluated. All TKAs were performed to achieve neutral MA by a medial stabilising gap balancing technique. Pre- to postoperative change in aHKA was defined as ΔaHKA. The 80 CPAK type I knees were divided into a larger ΔaHKA group (>7°) and a smaller ΔaHKA group (≤7°). PROMs, including the Knee Society Score and Forgotten Joint Score-12, were assessed before and 2 years after surgery. Pre- and postoperative joint laxity was assessed using a Telos arthrometer. Twenty-two knees showed a larger ΔaHKA, and postoperative lateral joint laxity in varus stress was significantly greater in these patients than in those with a smaller ΔaHKA (6.8° vs. 4.5°, p = 0.006). There were no significant differences between the groups in PROMs (p = n.s.). Postoperative lateral laxity was associated with larger aHKA changes than smaller aHKA changes in CPAK type I knees after TKA. However, no statistically significant differences in PROMs were found according to the amount of change in aHKA. Level III.