Search Results (56)

Whole-leg radiographs (WLRs) are widely used to assess coronal alignment before total knee arthroplasty (TKA), but may be inaccurate in patients with atypical morphotypes or malrotation. This study evaluated the discrepancy between WLR and 3D computed tomography (CT) scans across coronal plane alignment of the knee (CPAK) morphotypes and introduced a novel projection index—the femoral notch projection ratio (FNPR). In CPAK III knees, 19% of cases exceeded a clinically relevant threshold (>3° difference), prompting investigation of underlying projection factors. In 187 knees, coronal angles—including the medial distal femoral angle (MDFA°), medial proximal tibial angle (MPTA°), femoral mechanical angle (FMA°), and arithmetic hip–knee–ankle angle (aHKA°)—were measured using WLR and CT. Rotational positioning on WLR was assessed using FNPR and the patellar projection ratio (PPR). CPAK classification was applied. WLR systematically underestimated alignment, with the greatest bias in CPAK III (MDFA° + 1.5° ± 2.0°, p < 0.001). FNPR was significantly higher in CPAK III and VI (+1.9° vs. −0.3°, p < 0.001), indicating a tendency toward internally rotated limb positioning during imaging. The PPR–FNPR mismatch peaked in CPAK III (4.1°, p < 0.001), suggesting patellar-based centering may mask rotational malprojection. Projection artifacts from anterior osteophytes contributed to outlier measurements but were correctable. Valgus morphotypes with oblique joint lines (CPAK III) were especially prone to projection error. FNPR more accurately reflected rotational malposition than PPR in morphotypes prone to patellar subluxation. A 3D method (e.g., CT) or repeated imaging may be considered in CPAK III to improve surgical planning. Full article

Background/Objectives: Limb malalignment disrupts physiological joint forces and predisposes individuals to the development of osteoarthritis. Surgical interventions such as distal femur or high tibial osteotomy aim to restore mechanical balance on weight-bearing joints, thereby reducing long-term morbidity. Accurate alignment is crucial since it cannot be adjusted after stabilization with plates and screws. Recent advances in personalized medicine offer the opportunity to tailor surgical corrections to each patient’s unique anatomy and biomechanical profile. This study evaluates the benefits of 3D planning and patient-specific cutting guides over traditional 2D planning with standard implants for alignment correction procedures. Methods: We assessed limb alignment parameters pre- and postoperatively in patients with varus and valgus lower limb malalignment undergoing acute realignment surgery. The cohort included 23 opening-wedge high tibial osteotomies and 28 opening-wedge distal femur osteotomies. We compared the accuracy of postoperative alignment parameters between patients undergoing traditional 2D preoperative X-ray planning and those using 3D reconstructions of CT data. Outcome measures included mechanical axis deviation and tibiofemoral angles. Results: 3D reconstructions of computerized tomography data and patient-specific cutting guides significantly reduced the variation in postoperative limb alignment parameters relative to preoperative goals. In contrast, traditional 2D planning with standard non-custom implants resulted in higher deviations from the targeted alignment. Conclusions: Utilizing 3D CT reconstructions and patient-specific cutting guides enhances the accuracy of postoperative limb realignment compared to traditional 2D X-ray planning with standard non-custom implants. Patient-specific instrumentation and personalized approaches represent a key step toward precision orthopedic surgery, tailoring correction strategies to individual patient anatomy and potentially improving long-term joint health. This improvement may reduce the morbidity associated with lower limb malalignment and delay the onset of osteoarthritis. Level of Evidence: Therapeutic Level III. Full article

Background/Objectives: Advanced destruction of the ankle and subtalar joints due to neuropathy, chronic infection, or inflammatory conditions presents a major surgical challenge, often resulting in limb amputation. This descriptive retrospective study aims to evaluate outcomes of reconstructive surgery in patients, in whom limb preservation was prioritized over amputation despite significant soft tissue and osseous involvement. Methods: Between January 2013 and December 2022, 31 reconstructive procedures were performed on 29 patients (16 women and 13 men) with severe hindfoot deformities. Etiologies included Charcot arthropathy (55%), osteomyelitis (25%), combined pathology (10%), and rheumatoid deformity with skin defect (10%). Surgical procedures included tibiotalocalcaneal arthrodesis (39%), astragalectomy with tibiocalcaneal arthrodesis (32%), tibiotalar arthrodesis (23%), and multistage procedures (6%). Fixation methods varied based on the extent of deformity and infection. The union was assessed via radiographs and CT imaging, and outcomes were statistically analyzed using Fisher’s exact test. Results: Successful arthrodesis was achieved in 74% of cases (23/31). The union rate was significantly influenced by the type and level of fixation (p = 0.0199), with the lowest rate observed in tibiotalocalcaneal arthrodesis using external fixation (17%). Complications included surgical site infection or abscess in 42% of cases, requiring reoperation in 35%. Limb amputation was ultimately necessary in five patients (16%). Conclusions: Despite high complication rates, limb-preserving reconstructive surgery remains a viable alternative to amputation in selected high-risk patients with severe hindfoot pathology. Appropriate preoperative planning, tailored surgical strategy, and patient compliance are essential to achieving functional limb salvage and restoring weight-bearing capacity. Full article

Background: ¹⁸F-NaF and ^99mTc-MDP are widely used bone imaging tracers, but their comparative uptake in bone versus cartilage is unclear. This study aimed to directly compare these patterns in rats to guide musculoskeletal molecular imaging. Methods: Male Sprague-Dawley rats underwent in vivo and ex vivo radiotracer studies. Tracer uptake (%ID/g) was quantified in bone and cartilage at 30, 60, or 120 min post-injection (¹⁸F-NaF or ^99mTc-MDP), and across different ages. Additional rats received subcutaneous implants of viable or devitalized bone and cartilage; uptake was assessed using PET/CT, autoradiography, and histology. Results: ¹⁸F-NaF showed faster blood/background clearance and higher target-to-background ratios compared to ^99mTc-MDP, especially in weight-bearing joint cartilage. ¹⁸F-NaF uptake in cancellous bone significantly exceeded that of ^99mTc-MDP, whereas ^99mTc-MDP showed higher uptake in knee cartilage. Age-related analysis showed maximal knee cartilage accumulation in aged rats. Histological and cell inactivation studies confirmed that ¹⁸F-NaF uptake reflects both cellular activity and degree of calcification. Conclusions:¹⁸F-NaF demonstrates distinctive, quantifiable uptake in cartilage, dependent on both cellular activity and calcification, and exhibits favorable imaging characteristics versus ^99mTc-MDP for cartilage metabolism. These findings support ¹⁸F-NaF as a promising tool for early diagnosis and therapeutic monitoring of bone and joint disorders, and provide pathophysiological insight into the dynamics of the bone–cartilage interface. Full article

Background: Complex hindfoot pathologies involving critical-sized bone defects of the talus are difficult to manage. The current management involves arthrodesis and bone grafting with the defective talus, which have limitations in restoring structural integrity and functional goals. The advancement of 3D-printed scaffolds has opened new avenues to address such complex hindfoot pathologies, which may potentially improve treatment outcomes. The addition of platelet-rich fibrin further enhances healing potential. Method: This is a retrospective study involving six patients with severe talar bone loss secondary to osteomyelitis or avascular necrosis, where 3D-printed scaffolds coated with PRF were implemented in salvage surgery performed from 2023 to 2024. We intended to investigate the clinical outcomes in terms of healing time and union rate. Additionally, we evaluated the degree of deformity corrections and the patients’ clinical outcomes. Results: This study reports six complex reconstructions which achieved CT-confirmed union after a mean duration of 20.2 weeks. All patients were able to ambulate with full weight bearing after an average duration of 23.3 weeks. The patients demonstrated improved radiological parameters, VAS scores from 7.5 ± 1.4 points to 2.3 ± 1.2, and functional scores in all domains for AOFAS, FFI and SF-36. Conclusion: This study demonstrates the benefits of PRF-coated 3D-printed scaffolds in managing complex hindfoot cases, especially in the presence of significant bony defects. This modality has the potential to achieve a good union rate, near-anatomical correction and good functional outcomes. Full article

Since its introduction, weight-bearing computed tomography (WBCT) has gained prominence due to its ability to produce accurate three-dimensional images under natural loading conditions, making it particularly useful for assessing complex foot deformities. This review aimed to focus on the diseases of the foot and categorized the pathological conditions into forefoot disease (hallux valgus), midfoot disease (Lisfranc injuries and midfoot osteoarthritis), and progressive collapsing foot deformity. For each category, the authors detail how WBCT enhances diagnostic accuracy and informs treatment strategies. In hallux valgus, WBCT allows for more precise measurement of established parameters and reveals crucial information about metatarsal pronation and ray instability. For midfoot pathologies, WBCT’s superiority in detecting subtle Lisfranc injuries and characterizing midfoot osteoarthritis is emphasized, highlighting the development of novel measurement techniques. The review extensively covers the application of WBCT in assessing the complex three-dimensional features of PCFD, including hindfoot valgus, midfoot/forefoot abduction, medial column instability, peritalar subluxation, and valgus tilting, presenting several WBCT-specific measurements and the use of distance mapping to quantify joint surface interaction. The authors conclude that WBCT, potentially enhanced through integration with artificial intelligence (AI), represents a significant advancement in foot and ankle care, promising improved diagnostic accuracy, streamlined treatment planning, and, ultimately, better patient outcomes. Full article

Our limb prostheses aim to restore Activities of Daily Living (ADLs) for amputees, with the socket being a critical component of trans-tibial prostheses influencing both comfort and functionality. Despite technological advancements, challenges such as fit, weight, and durability remain. This study investigates an additive manufacturing method for Total Surface Bearing (TSB) sockets, leveraging CT scans to create a Computer-Aided Design (CAD) and finite element (FE) model. Biomechanical behavior under static loading conditions were analyzed using FE analysis and resistive-based pressure sensors. The study found consistent pressure distribution across the residual limb, with deviations of 8.53 kPa and 4.46 kPa between FE analysis and experimental measurements. Mean pressures of 44.6 kPa and 22.11 kPa were observed under Full Body Weight (FBW) and Half Body Weight (HBW) conditions, respectively. The FE analysis demonstrated a uniform stress distribution in the prosthetic socket, with a maximum stress of 0.15 MPa and a deformation of 0.008 mm, highlighting the effectiveness of this approach in enhancing socket design. Full article

Background: Talar neck fractures are complex injuries that become particularly challenging when accompanied by bone loss or comminution. This case report introduces the use of an allograft bone screw as a novel method for bridging lateral comminution at the talar neck, providing structural support and promoting bone regeneration. Methods: A 20-year-old male sustained a comminuted talar neck fracture with subtalar and tibiotalar dislocation after a bouldering fall. Urgent surgical intervention involved open reduction and internal fixation using a two-incision technique. The medial key fragment was stabilized with two conventional compression screws, revealing a significant lateral bony defect. This was bridged and stabilized with an allogeneic cortical bone screw (Shark Screw^®, Surgebright GmbH, Lichtenberg, Austria), supplemented by bone replacement material. Results: At three months, CT confirmed fracture healing, and weight-bearing was initiated. At six months, the AOFAS score was 85/100 and FAAM 69/84, with no significant pain or swelling. By one year, the patient demonstrated full weight-bearing with occasional pain (AOFAS 88/100, FAAM 79/84). At two years, the patient achieved a pain-free range of motion and full activity participation (AOFAS 100/100, FAAM 83/84). Conclusions: The successful application of this technique illustrates the potential of allograft bone screws for stabilizing and bridging defects in talar neck fractures. Full article

Background/Objectives: Cancer cachexia is a multifactorial syndrome characterized by the progressive loss of skeletal muscle mass and adipose tissue. Dalbergia odorifer is widely used in traditional medicine in Korea and China to treat various diseases. However, its exact role and underlying mechanism in regulating cancer cachexia have not been elucidated yet. This research was conducted to investigate the effect of D. odorifer extract (DOE) in preventing the development of cancer-induced cachexia symptoms and figure out the relevant mechanisms. Methods: A cancer cachexia model was established in Balb/c mice using the CT26 colon carcinoma cell line. To evaluate the anti-cachexia effect of Dalbergia odorifer extract (DOE), CT26-bearing mice were orally administered with DOE at concentrations of 50 and 100 mg/kg BW for 14 days. C2C12 myotubes and 3T3L1 adipocytes were treated with 80% CT26 conditioned medium, DOE, and wortmannin, a particular AKT inhibitor to determine the influence of DOE in the AKT signaling pathway. Mice body weight, food intake, myofiber cross-sectional area, adipocyte size, myotube diameter, lipid accumulation, and relevant gene expression were analyzed. Results: The oral administration of DOE at doses of 50 and 100 mg/kg body weight to CT26 tumor-bearing mice resulted in a significant reduction in body weight loss, an increase in food intake, and a decrease in serum glycerol levels. Furthermore, DOE treatment led to an increase in muscle mass, larger muscle fiber diameter, and elevated expression levels of MyH2 and Igf1, while simultaneously reducing the expression of Atrogin1 and MuRF1. DOE also attenuated adipose tissue wasting, as evidenced by increased epididymal fat mass, enlarged adipocyte size, and upregulated Pparγ expression, alongside a reduction in Ucp1 and IL6 levels. In cachectic C2C12 myotubes and 3T3-L1 adipocytes induced by the CT26 conditioned medium, DOE significantly inhibited muscle wasting and lipolysis by activating the AKT signaling pathway. The treatment of wortmannin, a specific AKT inhibitor, effectively neutralized DOE’s impact on the AKT pathway, myotube diameter, and lipid accumulation. Conclusions: DOE ameliorates cancer cachexia through the expression of genes involved in protein synthesis and lipogenesis, while suppressing those related to protein degradation, suggesting its potential as a plant-derived therapeutic agent in combating cancer cachexia. Full article

Severe adult-acquired flatfoot deformity is widely addressed surgically via the Grice–Green subtalar arthrodesis. Standard radiographic measurements have been reported, but these are limited to planar views. These complex deformities and the relevant corrections after surgery should be assessed in weight-bearing using 3D analyses now enabled by modern cone-beam CT scans. The present study is aimed at reporting these 3D radiographical foot bone alignments and the clinical results for this surgery. Ten patients were treated with the Grice–Green procedure. This implies inserting an autologous bone graft from the proximal tibial into the extra-articular sinus-tarsi to perform a subtalar arthrodesis. Before and after surgery, the patients were assessed based on the clinical range-of-motion and Foot-Function and Posture Indexes. Three-dimensional models of the tibia, calcaneus, talus, navicular, and 1st metatarsus were reconstructed from cone-beam CT scans in a single-leg up-right posture. Relevant longitudinal axes were defined to calculate ten spatial angles. Post-operatively, a significant realignment was observed for seven angles, including corrections lift-up of the talus (on average by 15°) and subtalar joint (13° in 3D), as well as the Meary’s angle (21°). Only few correlations were found between traditional clinical and novel 3D radiographical measurements, suggesting the former only limitedly represent the corresponding real skeletal status, and the latter thus offer the physician a more comprehensive evaluation. The present original analysis from modern cone-beam CT scans shows precisely the correction of foot and ankle bone alignments achieved using the Grice–Green surgical procedure, finally in 3D and in weight-bearing. For the first time, traditional clinical and score system evaluations are reported together with bone orientation and joint angles in the three anatomical planes. Full article

Weight-bearing computed tomography (WBCT) enables acquisition of three-dimensional bony structure images in a physiological weight-bearing position, which is fundamental in understanding the pathologic lesions and deformities of the ankle joint. Over the past decade, researchers have focused on validating and developing WBCT measurements, which has significantly enhanced our knowledge of common foot and ankle diseases. Consequently, understanding the application of WBCT in clinical practice is becoming more important to produce improved outcomes in the treatment of disease around the ankle joint. This review will describe an overview of what is currently being evaluated in foot and ankle surgery using WBCT and where the course of research will be heading in the future. Full article

Background: Although Total Ankle Arthroplasty (TAA) is primarily performed for post-traumatic ankle arthritis with joint disruption, anatomical landmarks for Joint Line (JL) level are typically preserved. However, severe Post-Traumatic Bone Loss (PTBL) or TAA revision may render some landmarks unidentifiable, challenging JL restoration. Methods: Patients undergoing customized TAA for severe PTBL or revision were enrolled. Custom-made implants, based on 3D CT scans, were designed to address bone defects and provide adequate bone support. Evaluated parameters, measured on bilateral ankle weight-bearing radiographs taken preoperatively and 6–8 months postoperatively, included JL Height Ratio (JLHR) and the distances from JL to the Lateral Malleolus apex (LM-JL), the posterior colliculus of the Medial Malleolus (MM-JL), and the Gissane Calcaneal Sulcus (CS-JL). Reproducibility and variability were assessed, and comparisons were made between radiological parameters measured at TAA and those at the contralateral ankle. Results: Thirteen patients were included. Intra- and interobserver reliability demonstrated excellent values. The least variability was observed in the LM-JL distance. Statistically significant correlations were found between CS-JL and MM-JL distances in the operated limb and between the CS-JL of the operated limb and the contralateral ankle. While TAA parameters did not show statistically significant differences compared with the contralateral ankle, a trend toward proximalization of the JL was noted. Conclusions: This study demonstrated good reproducibility of the analyzed parameters for evaluating JL in TAA among patients with severe PTBL or undergoing revision surgery. However, these parameters cannot be deemed fully reliable. Given their potential weaknesses, it is crucial to identify more reproducible values, preferably ratios. Full article

The decade from 2010–2020 has seen the development of cone beam weight-bearing CT (WBCT) as a major innovation in the foot and ankle realm, becoming an important modality for bone and joint imaging. The ability to provide three-dimensional images of the naturally loaded skeleton has enabled several subsequent innovations to arise with aims to hasten image processing and to extend the clinical applications of WBCT. The objective of this work was to identify, categorize and explain those emerging techniques. We performed a structured review of the literature according to PRISMA standards, finally including 50 studies. We subsequently proposed a classification of these techniques. Segmentation and distance mapping were identified as key features. We conclude that although WBCT has already been adopted in a number of clinical communities with an immediate improvement in patient workflows, adoption of advanced techniques is yet to come. However, that relies mostly not on the technology itself, but on improvements in AI software allowing practitioners to quickly process images in daily practice and enabling the clinicians to obtain an accurate three-dimensional evaluation of the segment considered. Standardization will be paramount to amass large amounts of comparable data, which will fuel further innovations in a potentially virtuous circle. Full article

Bone cancer and its related chronic pain are huge clinical problems since the available drugs are often ineffective or cannot be used long term due to a broad range of side effects. The mechanisms, mediators and targets need to be identified to determine potential novel therapies. Here, we characterize a mouse bone cancer model induced by intratibial injection of K7M2 osteosarcoma cells using an integrative approach and investigate the role of capsaicin-sensitive peptidergic sensory nerves. The mechanical pain threshold was assessed by dynamic plantar aesthesiometry, limb loading by dynamic weight bearing, spontaneous pain-related behaviors via observation, knee diameter with a digital caliper, and structural changes by micro-CT and glia cell activation by immunohistochemistry in BALB/c mice of both sexes. Capsaicin-sensitive peptidergic sensory neurons were defunctionalized by systemic pretreatment with a high dose of the transient receptor potential vanilloid 1 (TRPV1) agonist resiniferatoxin (RTX). During the 14- and 28-day experiments, weight bearing on the affected limb and the paw mechanonociceptive thresholds significantly decreased, demonstrating secondary mechanical hyperalgesia. Signs of spontaneous pain and osteoplastic bone remodeling were detected both in male and female mice without any sex differences. Microglia activation was shown by the increased ionized calcium-binding adapter molecule 1 (Iba1) immunopositivity on day 14 and astrocyte activation by the enhanced glial fibrillary acidic protein (GFAP)-positive cell density on day 28 in the ipsilateral spinal dorsal horn. Interestingly, defunctionalization of the capsaicin-sensitive afferents representing approximately 2/3 of the nociceptive fibers did not alter any functional parameters. Here, we provide the first complex functional and morphological characterization of the K7M2 mouse osteosarcoma model. Bone-cancer-related chronic pain and hyperalgesia are likely to be mediated by central sensitization involving neuroinflammation via glial cell activation in the spinal dorsal horn, but not the capsaicin-sensitive sensory neuronal system. Full article

Every year, almost 4 million patients received medical care for knee osteoarthritis. Osteoarthritis involves progressive deterioration or degenerative changes in the cartilage, leading to inflammation and pain as the bones and ligaments are affected. To enhance treatment and surgical outcomes, various studies analyzing the biomechanics of the human skeletal system by fabricating simulated bones, particularly those reflecting the characteristics of patients with knee osteoarthritis, are underway. In this study, we fabricated replicated bones that mirror the bone characteristics of patients with knee osteoarthritis and developed a skeletal model that mimics the actual movement of the knee. To create patient-specific replicated bones, models were extracted from computerized tomography (CT) scans of knee osteoarthritis patients. Utilizing 3D printing technology, we replicated the femur and tibia, which bear the weight of the body and support movement, and manufactured cartilage capable of absorbing and dispersing the impact of knee joint loads using flexible polymers. Furthermore, to implement knee movement in the skeletal model, we developed artificial muscles based on shape memory alloys (SMAs) and used them to mimic the rolling, sliding, and spinning motions of knee flexion. The knee movement was investigated by changing the SMA spring’s position, the number of coils, and the applied voltage. Additionally, we developed a knee-joint-mimicking system to analyze the movement of the femur. The proposed artificial-skeletal-model-based knee-joint-mimicking system appears to be applicable for analyzing skeletal models of knee patients and developing surgical simulation equipment for artificial joint replacement surgery. Full article