Coronal Deformity Research Articles

Automated Measurement of Pelvic Parameters Using Convolutional Neural Network in Complex Spinal Deformities: Overcoming Challenges in Coronal Deformity Cases.

Accurate and consistent measurement of sagittal alignment is challenging, particularly in patients with severe coronal deformities, including degenerative lumbar scoliosis (DLS). This study aimed to develop and validate an artificial intelligence (AI)-based system for automating the measurement of key sagittal parameters, including lumbar lordosis, pelvic incidence, pelvic tilt, and sacral slope, with a focus on its applicability across a wide range of deformities, including severe coronal deformities, such as DLS. Retrospective observational study. A total of 1,011 standing lumbar lateral radiographs, including DLS. Interclass and intraclass correlation coefficients (CC), and Bland-Altman plots. The model utilizes a deep-learning framework, incorporating a U-Net for segmentation and a Keypoint Region-based Convolutional Neural Network for keypoint detection. The ground truth masks were annotated by an experienced orthopedic specialist. The performance of the model was evaluated against ground truth measurements and assessments from two expert raters using interclass and intraclass CC, and Bland-Altman plots. In the test set of 113 patients, 39 (34.5%) had DLS, with a mean Cobb's angle of 14.8° ± 4.4°. The AI model achieved an intraclass CC of 1.00 across all parameters, indicating perfect consistency. Interclass CCs comparing the AI model to ground truth ranged from 0.96 to 0.99, outperforming experienced orthopedic surgeons. Bland-Altman analysis revealed no significant systemic bias, with most differences falling within clinically acceptable ranges. A 5-fold cross-validation further demonstrated robust performance, with interclass CCs ranging from 0.96 to 0.99 across diverse subsets. This AI-based system offers a reliable and efficient automated measurement of sagittal parameters in spinal deformities, including severe coronal deformities. The superior performance of the model compared with that of expert raters highlights its potential for clinical applications.

Posterior cruciate ligament resection increases intraoperative lateral and medial flexion laxity during total knee arthroplasty.

This study reports the relationship between posterior cruciate ligament (PCL) retention vs resection and soft tissue laxity and balance throughout flexion using a robotically controlled ligament tensioner. 55 robotic-assisted TKAs (Total knee arthroplasty) were retrospectively reviewe. The robotic ligament tensioner collected laxity data both before and after PCL resection. Medial and lateral coronal laxity were compared before and after PCL resection at 10°, 45°, and 90° flexion. Gap opening was compared between pre-operative coronal hip-knee-ankle groups. Lateral laxity was greater after PCL resection at 60° (12.7 ± 2 vs 11.5 ± 3mm), 75° (13.2 ± 2 vs 11.8 ± 3mm), and 90° (13.7 ± 2 vs 12.1 ± 3mm). Medial laxity was significantly greater after PCL resection at 90° (10.1 ± 2 vs 9 ± 2mm). After PCL resection, laxity in valgus knees increased more compared to neutral/varus knees laterally at 30° (1.2 ± 1 vs 0.3 ± 1mm), 45° (1.6 ± 1 vs 0.6 ± 1mm), and 60° (2.1 ± 2 vs 1 ± 1mm). A similar, but non-significant trend was observed at 90° (2.7 ± 2 vs 1.5 ± 1mm, p = 0.09). PCL resection increases flexion laxity laterally by up to 1.6mm and medially by 1.1mm on average, with valgus knees increasing more than neutral/varus knees. The findings emphasize that surgeons should consider the interplay between PCL resection and coronal deformity when planning and executing TKA procedures.

Machine learning can predict surgical indication: new clustering model from a large adult spine deformity database.

The choice of the best management for Adult Spine Deformity (ASD) is challenging. Health-related quality of life (HRQoL), comorbidities, symptoms and spine geometry, along with surgical risk and potential residual disabilityplay a role, and adefinite algorithm for patient management is lacking. Machine learning allows to analyse complex settingsmore efficiently than other available statistical tools. Aim of this study was to develop a machine-learning algorithm that, based on baseline data, would be able to predict whether an ASD patient would undergo surgery or not. Retrospective evaluation of prospectively collected data.Demographic data, HRQoL and radiographic parameters were collected. Two clustering methodswereperformed to differentiate groups of patients with similar characteristics. Threemodels were then used to identify the most relevant variables for management prediction. Data from 1319 patients were available. Three clusters were identified:older subjects with sagittal imbalance and high PI, younger patientswith greater coronal deformity and no sagittal imbalance,older patients with moderate sagittal imbalance and lower PI.The group of younger patients showed the highest error rate for the prediction (37%), which was lower for the other two groups (20-27%). For all groups, quality of life parameters such as the ODI and the SRS 22 and the Cobb angle of the major curve were the strongest predictors of surgical indication, albeit with different odds ratios in each group. Threeclusters could be identifiedalong with the variables that, in each, are most likely to drive the choice of management.

Patient-Specific Rods vs Traditional Rods in Surgical Correction of Adult Spinal Deformities: A Case-Matched Study.

Patient specific pre-contoured rods (PSRs) represent a relatively new technological development aimed at improving surgical outcomes and reducing complications in adult spinal deformity surgery. To date, only a limited number of studies have been published comparing PSRs with traditional spinal rods. In this paper, we compare the surgical, imaging, and clinical outcomes of PSRs and traditional spinal rods in a single-center case-matched study. Thirty cases of adult spinal deformities (ASD) were retrospectively analysed. These included 10 patients who were operated on using UNiD™ (Adaptive Spine Intelligence, MedTronic, Minneapolis, MN, USA) PSRs and 20 operated on using traditional rods from January 2023 to August 2023. Minimum post-surgical follow-up was 6 months. General demographics and standard radiographic parameters, as well as Scoliosis Research Society (SRS)-22, Oswestry Disability Index (ODI) and Short Form Health Survey (SF-12) Scores, were measured at pre-operative examination and at 6-month follow-up. Follow-up imaging data were compared with software-planned correction goals. Intra-operative data and complications were also recorded. Patients in the two groups were matched in terms of age, body mass index (BMI), sex, type and severity of spinal deformity. The magnitude of the coronal deformity (p = 0.812) and preoperative sagittal imbalance (p = 0.845) were similar between the two groups. The number of fused levels (p = 0.439), osteotomies (p = 0.188), implant density (p = 0.880), and surgery duration (p = 0.299) were similar between the two groups. Sagittal correction goals set during preoperative planning were achieved in the PSRs group, with the exception of pelvic tilt (PT) (p = 0.042). In contrast, PT (p = 0.040), L1-S1 lordosis (p = 0.032) and global tilt (GT) (p = 0.001) remained significantly undercorrected in the control group at 6-month follow-up. Clinical outcomes (ODI and SF-12 Scores) and complication rates were similar between the two groups. The use of PSRs improves the achievement of better post-operative spinopelvic alignment in adult spinal deformity surgery. Moreover, no significant differences were noted in terms of complications, operative times, and clinical outcomes compared to traditional spinal rods at 6-month follow-up.

Early Experience With the Quantum Total Ankle Prosthesis.

The Quantum total ankle prosthesis is a newer Food and Drug Administration (FDA)-approved fourth-generation 2-component, fixed-bearing implant in its first-generation design. The purpose of this study was to evaluate early outcome data and present our initial experience with the Quantum implant with a minimum of a 1-year follow-up. A retrospective, single-centered chart and radiographic review was performed on all patients who underwent total ankle arthroplasty with the Quantum implant from December 2021 to August 2023. Implant survivorship, radiographic outcomes, clinical outcomes, and complications were evaluated. The survivorship for the implant was 100% for the tibial component and 91.67% for the talar component, respectively. Pre-operatively, there were 3 ankles with a coronal deformity greater than 10 degrees. Post-operatively, coronal plane deformity was 100% corrected into neutral alignment. This study is the first to report on short-term outcomes for the Quantum total ankle prosthesis. Our findings showed promising results of short-term implant survivorship with good clinical and radiographic outcomes.Level of Evidence: IV.

Preoperative difference between 2D and 3D planning correlates with difference between planned and achieved surgical correction in patient-specific instrumented total knee arthroplasty.

The goals of this study were (1) to assess whether the preoperative difference between modalities and extent of deformity are associated with a higher difference between planned and achieved surgical correction and (2) if they yield a higher probability of intraoperative adjustments. Retrospective single-centre analysis of patients undergoing patient-specific instrumented (PSI) total knee arthroplasty (TKA). Preoperative radiographic parameters were analysed on weightbearing (WB) long-leg radiographs (LLR) and nonweightbearing (NWB) computed tomography (CT). The 2D/3D difference was calculated as the difference between preoperative WB-LLR (2D) hip-knee-ankle angle (HKA), and NWB CT (3D) HKA. Surgical records were screened to retrieve intraoperative adjustments to the preoperative plan. Postoperative assessment was performed on WB LLR. Two-hundred-eighty-two knees of 263 patients were analysed. The difference of postoperative achieved to planned HKA (HKADifference) was 2.2° ± 1.7°. The preoperative 2D HKA showed the highest correlation with HKADifference (r = -0.37, 95% confidence interval [CI]: -0.48 to -0.26, p < 0.001). Intraoperative adjustments were performed in 60% (n = 170) of all knees. Patients with a preoperative coronal deformity of >7.8° had 10.55 higher odds for an intraoperative coronal adjustment (95% CI: 4.60-24.20, p < 0.001). The extent of deformity is associated with residual coronal deformity following PSI-TKA. Patients with extensive coronal malalignment may benefit from an adaptation of the preoperative surgical plan to avoid unintended postoperative coronal malalignment. Despite the advancements with 3D preoperative planning, intraoperative adjustments in PSI-TKA are frequently performed, in particular in patients with a higher preoperative varus/valgus deformity. Level III.

Anterior Vertebral Body Tethering (AVBT) in the Treatment of Adolescent Idiopathic Scoliosis: A Retrospective Study.

Background/Objectives: Anterior Vertebral Body Tethering (AVBT) is a relatively novel minimally invasive surgical technique for the treatment of adolescent idiopathic scoliosis (AIS) that enables deformity correction of the spine diminishing vertebral motion reduction caused by the standard posterior spinal fusion approach. This paper reports the introduction of a new technical variant of AVBT, with the aim of evaluating its effectiveness on the correction of both axial and coronal spinal deformity. Methods: A single-centre single-surgeon retrospective cohort study was conducted. AVBTs were performed between 2020 and 2024. Radiographical values, surgical details, and complications of 67 patients affected by AIS were compared before surgery, immediately after surgery, and at the most recent follow-up. Results: Postoperative results have revealed a statistically significant coronal curve correction of 29.85% in the main thoracic (MT) curves (from mean preoperative width of 54.81 ± 11.86° to 38.45 ± 10.19°) and of 26.93% in the thoracolumbar (TL/L) curves (from 35.15 ± 11.83° to 25.69 ± 10.50°) in line with that obtained by the standard technique. Coronal correction at the most recent follow-up was maintained. Postoperative axial rotation reduction was found to be statistically significant in the main thoracic (MT) curves (from mean Nash-Moe value of 1.84 ± 0.71 to 1.36 ± 0.73), with a further decrease at the most recent follow-up compared with preoperative values. Improvement in other radiographical measures did not reach statistical significance and the complication rate was comparable to the standard technique. Conclusions: The extent of coronal correction in patients treated with the proposed modified AVBT technique is satisfactory and in line with results from studies testing the standard AVBT technique. The findings of this study seem to suggest that this technical variant of AVBT is effective in the correction of both axial and coronal deformity, with a surgical complication rate comparable to the standard technique.

Management of Type III Occipital Condyle Fractures.

Background/Objectives: Occipital condyle fractures (OCFs) can be seen in around 4-19% of patients who suffer from cervical spine trauma. Anderson and Montesano system type III OCFs, which are avulsion fractures, are potentially unstable and operative. This study evaluates the management of type III OCFs at our institution over a 22-year period. Methods: This retrospective study reviewed all cases of type III OCFs at our institution from July 2001 to March 2023, identified via imaging reports. Using the in-house radiology imaging informatics system "Doris" (Dig Our Radiology Information System), reports containing the terms subluxation, avulsion, unstable, or type 3/III with occipital condyle, occipital condylar, occipital fx, or occipital fracture were collected. We also searched for Montesano type III/3 fracture. Electronic medical records were used to collect clinical and demographic data. Patients evaluated by the neurosurgical team with at least 1 month of follow-up were included in the analysis. Results: A total of 563 patients were identified with type III OCFs. A total of 56 patients met the inclusion criteria. The majority (91%, 51/56) were treated conservatively with cervical orthosis. A small subset (8.9%, 5/56) underwent occipito-cervical fusion. Three had concomitant unstable C1 fractures, while the other two had significant coronal deformity associated with their type III OCF. Conclusions: At our institution, type III OCFs are predominantly managed with cervical orthosis. Only those with an associated malalignment of the occipito-cervical joint underwent fusion. These findings suggest that most type III OCFs can be treated conservatively with orthosis once stability is confirmed with an upright radiograph.

Influence of coronal lumbar Cobb angle and surgical level on short-segment lumbar surgery outcomes in degenerative scoliosis.

This study investigates the relationship between surgical levels and coronal deformity to identify risk factors for failing to achieve a minimal clinically important difference (MCID) in the Oswestry Disability Index (ODI) following short-segment isolated decompression or fusion surgery in patients with degenerative scoliosis (DS) and concurrent lumbar canal stenosis (LCS), without severe sagittal deformity malalignment. Patients with degenerative scoliosis who underwent 1- or 2-level lumbar isolated decompression or fusion surgery were included. Surgical level was labeled as "Cobb-related" when decompression or surgical levels spanned or were between end vertebrae, and "outside" when the operative levels did not include the end vertebrae. Logistic regression analysis was conducted to assess the factor associated with MCID achievement in ODI at 1 year postoperatively. A total of 129 DS patients with LCS and preoperative ODI > 30 were included. At 1-year follow-up, 91 patients (70.5%) achieved MCID in ODI. No significant differences were found in demographics or overall spinal alignment between patients who did and did not achieve MCID. Logistic regression analysis revealed that Cobb-related decompression was independently associated with decreased odds of achieving MCID in ODI (adjusted Odds Ratio 0.18, 95% CI 0.42-0.79, P = 0.025). In patients with mild to moderate coronal deformity and minimal sagittal deformity, decompression alone at or across end vertebrae significantly lowers the likelihood of achieving the MCID in ODI compared to fusion surgery, with an 84% reduction in odds. No significant difference in MCID achievement was observed between decompression and fusion surgeries outside the Cobb angle.

Transfibular Total Ankle Arthroplasty: Clinical, Functional, and Radiographic Outcomes and Complications at a Minimum of 5-Year Follow-up.

The Trabecular Metal Total Ankle Implant differs from other newer-generation implants in the transfibular approach, multiplanar external frame for alignment, tantalum trabecular metal interfaces, curved geometry, and shallow resection depths. The primary aim of this study was to report midterm clinical and radiographic results, as well as survivorship and adverse events at a minimum of 5-year follow-up. A total of 83 ankles (81 patients, average age 60.6 years old, 50.6% females) with average 6.3 years' (range, 5.0-10.1) follow-up were included. Postoperative patient-reported outcome measures (PROMs) included SF-12 physical (PCS) and mental component summary (MCS) scores, Ankle Osteoarthritis Scale (AOS), pain visual analog scale (VAS). Radiographic outcomes included postoperative range of motion (ROM) and coronal/sagittal alignment. Adverse events were reported using the Canadian Orthopaedic Foot and Ankle Society Reoperation Coding System (CROCS). Preoperative tibiotalar coronal deformity included 27 valgus (10 degrees, range 2-20 degrees) and 25 varus ankles (-9 degrees, range -2 to -25 degrees), corrected to neutral postoperatively. Postoperative tibiopedal ROM was 17.8 degrees dorsiflexion and 21.8 degrees plantarflexion. Adverse events occurred at average 28.7 months, most commonly gutter debridement (n = 17, 16.7%) and subsequent operative treatment unrelated to metal components (n = 10, 12.0%). There were 2 cases (2.4%) of acute deep infection treated with irrigation and debridement, polyethylene exchange, and retention of metal components without recurrence of infection. There were no cases of fibular nonunion, septic or aseptic loosening, or implant subsidence. Postoperative PROMS included SF-12 PCS: 40.4; SF-12 MCS: 56.0; VAS: 2.3; AOS Pain: 17.0; and AOS Disability: 24.9. Overall implant survival, defined by retention of the metal components, was 100% at final follow-up. At a minimum of 5 years, patients who underwent TM TAA reported minimal ankle pain and regained neutral ankle alignment and mobility, without septic or aseptic implant loosening. Although having certain limitations, this study suggests that TM TAA is a viable option for the treatment of end-stage ankle arthritis.

Short-segment fusion versus isolated decompression in lumbar spinal canal stenosis patients with Cobb angles over 20 degrees

BACKGROUND CONTEXTLumbar decompression and short-segment lumbar fusion are standard procedures for short-segment lumbar canal stenosis, even in patients with moderate Cobb angles. Adult degenerative scoliosis is diagnosed at a threshold of 10 degrees, and patients with coronal Cobb angles over 30 degrees are recommended for long fusion due to global spinal deformity. However, there is a lack of research on clinical outcomes in patients with moderate coronal deformity, such as Cobb angles between 20 and 30 degrees. PURPOSEThis study aims to investigate the radiographic and clinical outcome differences between isolated decompression and short-segment interbody fusion for lumbar spinal canal stenosis in patients with moderate coronal deformity. STUDY DESIGNA retrospective analysis of a prospectively collected registry. PATIENT SAMPLEPatients with Cobb angle exceeding 20 degrees who underwent 1- or 2- levels of lumbar surgery for lumbar canal stenosis. Patients diagnosed as spinal deformity were excluded. OUTCOME MEASURESPatient-reported outcomes included Oswestry Disability Index (ODI), VAS back, VAS leg, Short form 12 physical component score (SF-12 PCS) and Mental Component Score (SF-12 MCS), and patient-reported outcomes measurement information system physical function (PROMIS-PF) at preoperative, 12-week postoperative, and 1-year postoperative timepoints. Preoperative and postoperative spinopelvic alignment was assessed using Cobb angle, pelvic tilt, sacral slope, pelvic incidence, lumbar lordosis and PI minus LL. METHODSA propensity score-matched analysis with the overlap weighting was utilized to investigate patient-reported outcomes at 12-week and 1-year postoperatively between the surgery groups. Spinopelvic alignments were compared between preoperative and 1-year postoperative timepoint using a linear mixed-effect model. RESULTSBefore overlap weighting, the two surgery groups showed significant differences in age and diagnosis. No obvious sagittal malalignment was observed (PI minus LL: decompression, 7.4° vs. fusion, 11.5°). After propensity score weighting, the fusion groups exhibited significantly better ODI and VAS back at the 1-year timepoint (ODI: fusion, 16.6 vs. decompression, 28.1, p=.013; VAS back: fusion, 1.5±2.1 vs. decompression, 3.7±1.9, p<.001). Radiographic assessment showed that the fusion group achieved better PI minus LL compared to decompression group (15° vs. 10°, p=.008). CONCLUSIONIn patients with degenerative scoliosis and a Cobb angle greater than 20 degrees, short-segment lumbar fusion surgery may result in enhanced improvement for short-segment lumbar pathology compared to isolated decompression.

Difference in Rotational Alignment of the Tibial Component, as Determined by the Range-of-Motion Technique and Akagi&apos;s Line, is Influenced by Tibial Varus Deformity: A Cross-Sectional Study

Anatomical landmarks and range-of-motion (ROM) techniques are commonly used to rotationally align the tibial component in total knee arthroplasty (TKA). This study investigated; 1) the difference in tibial rotational alignment between the ROM technique and Akagi's line, 2) the influence of preoperative deformity and intraoperative gaps on this difference, and 3) intraoperative tibial rotational kinematics associated with these 2 techniques. Patients who underwent cruciate-substituting (CS) TKA (Evolution, Microport Orthopedics) for knee osteoarthritis were enrolled. Intraoperatively, the rotational alignment of the tibial component was determined with the ROM technique and recorded. The difference from the value determined using Akagi's line was evaluated. Correlations among preoperative coronal deformity, postoperative coronal alignment, and intraoperative gaps between the femur and tibia were evaluated. Differences in knee kinematics (rotational movement of the tibia against the femur) between the 2 techniques were compared. This study included 34 knees from 34 patients. The rotational alignment of the tibial component using the ROM technique was 2.5±6.4° externally rotated in relation to that determined using Akagi's line (p=0.029), which was increased in knees with a smaller preoperative medial proximal tibial angle (r=0.45). Tibial rotational kinematics did not significantly differ between the 2 techniques. The ROM technique and Akagi's line yielded significantly different values for the rotational alignment of the tibial component. Orthopedic surgeons using Evolution (CS) should be reminded that in knees with proximal tibial varus deformity, the ROM technique will result in external rotation of the tibial component in relation to Akagi's line.

Impact of Implant Design and Coronal Deformity on Revision and Reoperation Rates in Total Ankle Arthroplasty: A Comparative Study

Category: Ankle Arthritis; Ankle Introduction/Purpose: Literature trends indicate a generally lower rate of reoperation and revision associated with the fixed-bearing two-component design implant compared to the mobile-bearing three-component design for total ankle arthroplasty (TAA). Coronal deformity is also linked to poorer outcomes following TAA. The aim of this study was to assess the impact of intra-articular coronal deformity (non-concentric ankle arthritis) on both fixed and mobile implant designs. We hypothesized that non-concentric ankle arthritis and mobile bearings would be associated with a higher early revision rate. Methods: This IRB approved retrospectivelreviewed 202 patients who underwent TAA with either mobile-bearing or fixed-bearing implants between 2007 and 2018. Patients who underwent TAA from 2007 to 2013 received the mobile-bearing implant, while those who underwent TAA after November 2012 received the fixed-bearing implant. Age, gender, ASA score, smoking status, BMI and eciology of the arthritis were reported from patients' record. Preoperative weight bearing x-ray were assessed for COFAS classification and intra-articular deformity. Non-concentric ankles were defined by a talar tilt angle greater than 4 degrees. The primary outcome was the rate of revision and reoperation within three years following the index procedure. Revision was defined as implants removal or exchange. Reoperation was defined as any additional surgery post-index surgery. The data underwent normality testing with the Shapiro-Wilk test, and comparisons were made via Kruskal-Wallis test and Chi square test. A p-value threshold of 0.05 or below was deemed significant. Results: All groups were not statistically different for age, gender, ASA score, BMI, and smoking status. Of the 76 patients who received a mobile-bearing implant, 33 had non-concentric arthritis, and 43 had concentric arthritis. Of the 126 patients who received a fixed-bearing implant, 61 had non-concentric arthritis, and 65 had concentric arthritis. In the mobile-bearing group, 8 patients underwent revision and 9 underwent reoperation. In the fixed-bearing group, 4 patients underwent revision and 10 underwent reoperation. In the non-concentric group revision rate was significantly higher (p&lt; 0.05) for the mobile-bearing implant (15.2%) compared to the fixed-bearing implant (0%) . In the concentric group, no significant difference in revision rates between the fixed-bearing (6.2%) and mobile-bearing designs (7%) was observed. Reoperation rates were similar across all groups. Conclusion: The study suggested that the use of mobile-bearing implants in patients with non-concentric arthritis is associated with a significantly higher revision rate compared to fixed-bearing implants. In patients with concentric arthritis, there was no significant difference in revision rates between the two implant designs. Additionally, the study found no significant difference in the reoperation rates across all groups. Preoperative intra-articular deformity seems to be a predictor of early revision rate after total ankle arthroplasty.

8-year survivorship of a 4th Generation Fixed Bearing Total Ankle Replacements

Category: Ankle Arthritis; Ankle Introduction/Purpose: The Infinity (Wright Medical Group) Total Ankle Replacement (TAR) has been implanted in patients since 2014 and is now the most common primary ankle used in the National Joint Registry of England and Wales. We report a prospective series of 106 Infinity TARs, with 8-year survivorship data from two, non-designer centres in the UK. The primary aims were to assess survivorship and complications of the Infinity TAR. The secondary aims were to assess patient reported and radiological outcomes. Methods: Prospectively collected data between March 2014 to December 2016 was assessed from two specialist centres in the United Kingdom. All operations were performed, or supervised, by one of 5 surgeons with a minimum experience of 10 TAR per year. Inclusion criteria were any patient with end-stage tibiotalar arthritis, considered by the operating surgeon to be suitable for primary TAR. Revision TAR, or conversion from arthrodesis, were not included in this study. Implant survivorship, complications, patient reported outcome scores (PROMS) and radiological data were collected for each patient. PROMS data comprised the Manchester Oxford Foot Questionnaire (MOX-FQ) and the EuroQol-5 Dimension (EQ5D-5L) score. Pre-operatively, weight bearing radiographs were assessed for the degree of sagittal and coronal deformity. Post-operatively, weight bearing radiographs at 6 weeks were assessed for the degree of deformity correction. Cystic radiolucencies on the most recent follow up radiograph was assessed by using an established scoring system. Results: 102 patients, comprising 106 TARs, were included. Mean age at implantation was 68 years (range 42 to 89 years). Mean follow up time was 98 months (range 83 to 113 months). 12 patients received further surgeries: 8 revision TARs, 3 debridement and grafting of talar cysts, and 1 capsular release. The reasons for revision surgery were unexplained pain (5 patients), proven deep infection (1 patient), tibial subsidence (1 patient) and instability (1 patient). Mean time to revision surgery was 43 months (range 15 to 82 months). Current survivorship of the cohort is 91%. Cystic radiolucencies were present in 35% of patients but the majority were small and asymptomatic. MOXFQ and EQ5D-5L PROMS showed significant and sustained post-operative improvements (p &lt; 0.01). Conclusion: This series of 106 modern fixed bearing TAR shows an 8-year survivorship of 91%. 3 cases of talar cysts were grafted. The most common reason for revision surgery was unexplained pain and the deep infection rate was 1%. The fixed bearing Infinity TAR appears to be a safe, effective intervention in the treatment of end stage ankle osteoarthritis and gives significant improvement in disease specific and general health status outcomes.

3D Semi-Automated Analysis of Joint Sparing Charcot-Marie-Tooth Cavovarus Reconstruction Using Preoperative and Postoperative Weightbearing Computed Tomography

Category: Hindfoot; Midfoot/Forefoot Introduction/Purpose: Charcot-Marie-Tooth (CMT) disease is the most common cause of cavus foot. The complex deformities in cavovarus feet of CMT disease are difficult to evaluate. The bone axes of CMT may be difficult to calculate by conventional weightbearing computed tomography (WBCT). For this reason, 3D automated measurements have been used to assess complex anatomy. The aim of this study was to quantitatively assess deformity correction following joint sparing CMT cavovarus reconstruction surgery. This is the first study investigating preoperative and postoperative WBCT findings in CMT feet using semi-automated 3D measurements. Methods: The study was approved by our institutional review board and informed consent was obtained from all patients. Joint sparing CMT surgery was performed with multiple soft tissue releases and bony procedures. Among the 170 cases from May 2021 to May 2023, twenty-nine CMT patients who had both pre- and postoperative WBCTs were retrospectively analyzed. 3D measurements of WBCT were performed using semi-automated software (Bonelogic 2.1, Disior) to investigate changes in sagittal, axial, and coronal parameters. Pre- and postoperative data was compared using a Wilcoxon signed-ranks test and these data were also compared with normative data using a Welch's t-test. Correlation among these sagittal, axial, and coronal parameters were analyzed using Spearman’s rank correlation coefficient test. Results: The sagittal, axial, and coronal malalignment of the hindfoot, and the sagittal and axial malalignment of the forefoot was significantly improved after corrective surgery (P &lt; .05). Sagittal Meary’s angle (from 14.8 degrees to 0.1 degrees), axial talonavicular angle (TNA, from 3.6 degrees to 19.2 degrees), and coronal hindfoot alignment (from 11.0 degrees to -11.1 degrees) showed significant changes postoperatively (P &lt; .001). Hindfoot, forefoot sagittal and forefoot axial parameters reached comparable outcomes compared to normative value (P &gt; .05). Regarding amount of correction, Spearman’s correlation demonstrated that axial Meary’s angle and TNA were most strongly related to improvement in sagittal Meary’s angle and coronal hindfoot alignment. Conclusion: Preoperative and postoperative WBCT measurements demonstrated that joint sparing CMT cavovarus reconstruction significantly improved sagittal, axial, and coronal deformities of CMT, and sagittal Meary’s angle was restored toward normative values. Apparent axial plane correction, the majority of which occurred at the talonavicular joint, had the strongest correlation with deformity correction in multiple planes. This suggests that soft tissue releases and correction of the talonavicular joint may be a key component of a CMT cavovarus foot correction. Figure. (A) CMT surgery with soft tissue releases and bony procedures, (B) Pre- and postoperative radiographic results, and gross photos of the operated right foot of a 17-year-old male patient.

High patient satisfaction with Customized Total Knee Arthroplasty at five year follow-up

PurposeDespite numerous studies demonstrating promising short-term outcomes of Total Knee Arthroplasty (TKA) with Customized Individually Made (CIM) implants, there is a significant lack of data on their mid-term effectiveness. Given the increasing number of TKAs performed annually, the rising demand for CIM implants, and the associated burden of revision surgeries, understanding the mid-term performance of CIM implants is crucial. Therefore, this study aims to report on the mid-term (minimum 5 years) outcomes of TKA using a CIM implant.MethodsThis retrospective cohort study included a consecutive series of 116 patients who received the ConforMIS® iTotal CR implant between 2015 and 2018. Inclusion criteria were end-stage knee osteoarthritis with coronal deformities below 10° and absence of ligamentous instability. Exclusion criteria included simultaneous bilateral TKA. Patients were followed up at a minimum of five years post-surgery. They completed a questionnaire reporting on satisfaction, pain levels using the Visual Analogue Scale (VAS), current weight, the Oxford Knee Score (OKS), and the Forgotten Joint Score for the knee (FJS-knee). Statistical analysis included descriptive statistics for demographic and clinical variables, and outcomes were reported as means with ranges.ResultsThe mean follow-up duration was 5.9 ± 0.8 years (range 5–7.4 years). 90% of patients stated they would undergo the same operation again, and 93% were either satisfied or very satisfied. The mean VAS for pain at rest was 2 ± 1.5 (range 0–6) and during exercise was 3 ± 2 (range 0–8). 58 patients (53%) managed to lose weight. The mean OKS was 41 ± 9 points (range 15–48), and the mean FJS-knee was 67 ± 23 points (range 4–100). No severe complications occurred.ConclusionCIM TKA using the ConforMIS® iTotal CR implant can achieve excellent results with 93% of patients being satisfied or very satisfied at mid-term follow-up of five years. Prospective, randomized, and patient-blinded trials comparing off-the-shelf (OTS) TKAs with CIM implants are necessary to evaluate whether these implants are superior or not.

Does the coronal deformity angular ratio affect bracing outcome in adolescent idiopathic scoliosis?

PurposeTo examine if coronal deformity angular ratio (C-DAR) serves as a predictor for progression to surgical magnitude in patients with Adolescent Idiopathic Scoliosis (AIS) treated with thoracolumbar sacral orthosis (TLSO).MethodsPatients with AIS, prescribed a full-time TLSO, Cobb angle 20–40°, Risser 0–2, who wore the brace ≥ 12.9 h and reached skeletal maturity/surgery were included retrospectively. C-DAR was defined as the Cobb angle divided by the number of vertebrae in the curve, yielding a larger value in short curves. The association between C-DAR and the risk of progression to surgical magnitude (> 45°) was assessed. Secondly, we evaluated the association between pre-treatment Cobb angle and in-brace correction on the risk of progression to > 45°.ResultsWe included 165 patients with a mean Cobb angle of 30 ± 6°. Of these, 46/165 (28%) progressed ≥ 6° and 26/165 (16%) reached surgical magnitude at the end of treatment. C-DAR was a significant predictor for risk of progression to surgical magnitude with an OR of 1.9 (CI 1.2–2.9) per unit increase in C-DAR. A threshold value of 5.15 was established and demonstrated an OR 5.9 (CI 2.1–17.9) for curve progression to a surgical magnitude. Likewise, pre-treatment Cobb angle showed a significant OR 1.3(CI 1.2–1.4) per degree increase in Cobb, whereas in-brace % correction showed OR 0.96 (CI 0.93–0.98).ConclusionC-DAR is an independent predictor for progression to a surgical magnitude in AIS patients treated with bracing. Patients with a higher C-DAR should be counseled to help set realistic expectations regarding the likelihood of curve progression despite compliance with brace wear.

Spino-pelvic parameters and back pain in patients without coronal deformity or history of spinal surgery: A cross-sectional analysis

BACKGROUND: During the last two decades, there has been a growing interest in spinal sagittal alignment. Most published studies have focused on the role of spinopelvic parameters in patients with adult spinal deformity or in those with previous spinal fusion. OBJECTIVE: The aim of this study was to explore possible association between disability related to back pain and spinopelvic parameters in the absence of coronal deformity or previous spinal surgery. METHODS: In the setting of a larger study involving patients with low back pain (LBP), those without previous surgery or spinal deformity in the coronal plane were selected. A total of 52 patients (mean age 59 years, range 21–86, 23 men and 29 women) were found. The visual analogic scale (VAS) and Oswestry Disability Index questionnaire (ODI) were recorded. Surgimap software was used to measure the sagittal vertical axis (SVA), pelvic tilt (PT), pelvic incidence (PI), sacral slope (SS), and lumbar lordosis (LL). Statistical analysis was performed with SPSS Statistics software. Pearson or Spearman correlation were the test of choice depending on the specific variables. RESULTS: A statistically significant association was found between SVA and ODI (r 0.59, p&lt; 0.03). Increased pelvic tilt was also associated with more severe disability related to back pain (r 0.48, p&lt; 0.03). PI-LL mismatch showed moderate association with disability and severity of back pain, although this association did not reach statistical significance (r 0.52, p&lt; 0.08). CONCLUSION: Our findings suggest that sagittal misalignment may be related with more severe disability and back pain in patients with minor or null deformity in the coronal plane.

The use of a modern robotic system for the treatment of severe knee deformities.

Robotic-assisted total knee arthroplasty (TKA) have shown promising results in recent years with improved clinical outcomes using standard primary implants. The purpose of this study was to assess the experience of a single center in correcting severe coronal deformities with the use of a robotic-assisted TKA system and an increased constrained implant. Between July 2020 and December 2022, 30 knees in 28 patients with a major deformity and an associated ligament laxity requiring an increased constrained implant treated using an imageless robotic-assisted TKA were prospectively enrolled. Patients included in the study showed a minimum 15 degrees varus or 10 degrees valgus deviation. 20 cases were varus knees and 10 cases were valgus knees. Postoperative neutral alignment was defined as 0∘± 2.5∘. A CCK implant was used in 20 cases while a Constrained Posterior Stabilized implant was used in 10 cases. A neutral alignment was achieved in all patients. At a minimum 6 months follow up (f-u 6-30 months) clinical outcomes including ROM, KSS, HSS, OKS and WOMAC showed significant improvement and no major complications were registered. The robotic system showed the achievement of a mechanical alignment with reliable radiographic outcomes and clinical results in the treatment of major deformities of the lower limb with the use of higher constrained implants at short term follow up. Further follow up and studies are necessary to confirm and verify these promising outcomes.

Bilateral Cruciate-retaining Image-free Robot-assisted Total Knee Arthroplasty Using Extended Restricted Kinematic Alignment in a Patient with Severe Varus Deformities

The management of severe coronal deformities during total knee arthroplasty (TKA) is challenging. Although conventionally considered to be a contraindication for cruciate-retaining TKA, severe varus deformities of ≥15° can be managed using cruciate-retaining prostheses and result in satisfactory outcomes if appropriate alignment and gap balance can be achieved. Robotic technology has enhanced the correction of complex deformities through virtual surgical planning, alternative alignment strategies, superior soft-tissue management, and personalized surgery. We present a case of bilateral osteoarthritis of the knees with severe varus deformities, managed through image-free robot-assisted TKA using extended restricted kinematic alignment and cruciate-retaining prostheses. Arthroplasty surgeons in developing countries need to be well-versed in multiple techniques for the management of osteoarthritis of the knee with severe coronal deformities. The technique presented by the authors would be a valuable tool in their armamentarium.