Search Results (10)

Background/Objectives: Patella alta contributes to patellofemoral (PF) maltracking and anterior knee pain, but the agreement of patellar-height indices across imaging modalities and their clinical relevance remain uncertain. We aimed to estimate the prevalence of patella alta when using each index, quantify inter-method agreement, and quantify patella alta’s associations with Hoffa’s fat-pad impingement, patellar chondromalacia, and tibial tubercle–trochlear groove (TT–TG) distance. Methods: This retrospective cross-sectional study included 250 patients aged 18–38 years who underwent both knee radiography and MRI. Patellar height was assessed using the Insall–Salvati (IS) and modified Insall–Salvati (mIS) ratios on radiographs and MRI, and the Patellotrochlear Index (PTI) on MRI. Associations with fat-pad impingement, chondromalacia grade, and TT–TG abnormality were analyzed using the chi-square or Fisher’s exact test and as odds ratios (ORs) adjusted for age, sex, and imaged side; agreement was assessed with Cohen’s kappa (κ). Results: Patella alta prevalence was 13.2% using IS on radiographs and 10.8% using IS on MRI, but markedly lower with mIS (≤1.6%). Patella alta was more frequent in patients with Hoffa’s fat-pad impingement (31.1% vs. 5.7% on IS radiography; adjusted OR 8.83, 95% CI 3.82–20.45) and advanced chondromalacia (p = 0.025). Agreement was moderate between IS radiography and IS MRI (κ = 0.47, 95% CI 0.33–0.61) and between IS MRI and the PTI (κ = 0.43). Conclusions: The prevalence and clinical relevance of patella alta depend strongly on the measurement method. The IS ratio was the most consistent index, but radiography–MRI agreement was moderate rather than high, so the two are not interchangeable. The PTI adds information on trochlear engagement from the same MRI examination. These cross-sectional associations do not establish causation. Full article

Background/Objectives: Patellar chondromalacia (PC) is a clinical condition characterized by early cartilage degeneration in the patellofemoral joint. This study aimed to investigate the relationship between the lateral-to-medial femoral condyle length ratio (LFCL/MFCL) measured on standard anteroposterior (AP) knee radiographs and the presence of PC. Methods: A retrospective analysis was conducted on patients who presented with anterior knee pain between 2020 and 2024. PC was diagnosed using magnetic resonance imaging (MRI). The LFCL/MFCL ratio was measured on plain radiographs. Additional morphological condylar parameters were evaluated on MRI. Symptom severity was assessed using the Kujala score. Statistical analyses included t-tests, correlation analysis, logistic regression, and receiver operating characteristic (ROC) curve analysis. Results: A total of 100 patients (50 with PC, 50 controls) were included. The LFCL/MFCL ratio was significantly higher in the PC group compared to controls (1.24 ± 0.19 vs. 1.08 ± 0.15, p = 0.002). A negative correlation was found between the LFCL/MFCL ratio and Kujala score (r = −0.322, p = 0.029). Other MRI-based parameters did not show statistically significant differences. In logistic regression, the LFCL/MFCL ratio was identified as an independent predictor of PC (p = 0.01). ROC analysis yielded an AUC of 0.743 (95% CI: 0.643–0.842). Conclusions: The LFCL/MFCL ratio, which can be easily measured on plain radiographs, may serve as a simple, cost-effective, and reproducible parameter to aid in the diagnosis of patellar chondromalacia. Further prospective studies with larger sample sizes are needed to validate this finding. Full article

Patellofemoral osteoarthritis (OA) and chondromalacia patellae (CMP) are common and disabling conditions that significantly affect physical performance and quality of life. Despite the great deal of scientific research on the subject, there is limited evidence regarding the outcome of nonoperative interventional procedures. Platelet-rich plasma (PRP) has demonstrated positive results for tibiofemoral knee osteoarthritis, but its role in anterior knee pain (AKP) remains unclear. The aim of this study was to review the evidence on the efficacy (clinical and radiological) and safety of PRP in patients suffering from patellofemoral OA, CMP, and AKP. Medline/Pubmed, Web of Science, and Scopus databases were systematically searched up to June 2025 to identify all the available relevant studies. Five studies, including 146 patients, fulfilled the eligibility criteria and were included in the systematic review. Although there was a statistically significant improvement in clinical setting, radiologic evidence of cartilage regeneration was limited and uncertain. Specifically, the pooled analysis revealed an improvement of the Visual Analogue Scale from 6.7 to 2.1 (p < 0.001), the Western Ontario and McMaster Universities Osteoarthritis Index score from 24 to 10.3 (p < 0.001), the Oxford score from 35.1 to 37.4 (p < 0.001), the Kujala score from 71 to 83 (p < 0.001), and the Tegner/Lysholm score from 65.3 to 86.5 (p < 0.001). Well-designed and appropriately powered randomized trials with imaging endpoints are needed to validate the efficacy of PRP administration in PFA, CMP, and AKP and refine patient selection criteria. Full article

Patellar pathologies are a common cause of knee dysfunction, with Patellofemoral Pain Syndrome (PFPS) alone responsible for 25% of knee-related visits to sports medicine clinics. Non-traumatic conditions, while often overlooked, can also lead to significant discomfort and functional limitations, highlighting the importance of accurate and timely diagnosis for effective management and prevention of complications. This pictorial review examines the radiologic characteristics of various non-traumatic patellar disorders, focusing on imaging modalities such as radiography, computed tomography (CT), and magnetic resonance imaging (MRI). Key diagnostic markers, including patellar tilt, tibial tuberosity–trochlear groove distance (TT-TG), and congruence angle (CA), are discussed for their significance in non-traumatic pathology identification. Furthermore, this review highlights specific radiologic features for a range of non-traumatic patellar conditions, including patellar tendinopathy, chondromalacia patellae, and trochlear dysplasia, emphasizing how distinct radiologic findings facilitate precise diagnosis and clinical assessment. Ultimately, it provides a practical guide for clinicians in diagnosing non-traumatic patellar pathologies through a comprehensive review of key radiologic features while also discussing advancements in imaging technologies and management strategies to support accurate diagnosis and effective clinical decision-making. Full article

Purpose: To evaluate magnetic resonance image (MRI) findings in children and adolescents suffering from knee pain without traumatic or physical overload history and to identify potential anatomic risk factors. Material and Methods: A total of 507 MRIs of 6- to 20-year-old patients (251 males; 256 females) were evaluated with regard to detectable pathologies of the knee. The results were compared to a control group without pain (n = 73; 34 males; 39 females). A binary logistic regression model and t-tests for paired and unpaired samples were used to identify possible risk factors and significant anatomic differences of the study population. Results: In 348 patients (68.6%), at least one pathology was detected. The most commonly detected finding was chondromalacia of the patellofemoral (PF) joint (n = 205; 40.4%). Chondral lesions of the PF joint occurred significantly more often in knee pain patients than in the control group (40% vs. 11.0%; p = 0.001), especially in cases of a patella tilt angle > 5° (p ≤ 0.001), a bony sulcus angle > 150° (p = 0.002), a cartilaginous sulcus angle > 150° (p = 0.012), a lateral trochlear inclination < 11° (p ≤ 0.001), a lateralised patella (p = 0.023) and a Wiberg type II or III patella shape (p = 0.019). Moreover, a larger patella tilt angle (p = 0.021), a greater bony sulcus angle (p = 0.042), a larger cartilaginous sulcus angle (p = 0.038) and a lower value of the lateral trochlear inclination (p = 0.014) were detected in knee pain patients compared to the reference group. Conclusion: Chondromalacia of the PF joint is frequently observed in children and adolescents suffering from non-overload atraumatic knee pain, whereby a patella tilt angle > 5°, a bony sulcus angle > 150°, a cartilaginous sulcus angle > 150°, a lateral trochlear inclination < 11°, a lateralised patella and a Wiberg type II or III patella shape seem to represent anatomic risk factors. Full article

Background: Patellofemoral instability (PFI) leads to chronic knee pain, reduced performance and chondromalacia patellae with consecutive osteoarthritis. Therefore, determining the exact patellofemoral contact mechanism, as well as the factors leading to PFI, is of great importance. The present study compares in vivo patellofemoral kinematic parameters and the contact mechanism of volunteers with healthy knees and patients with low flexion patellofemoral instability (PFI). The study was performed with a high-resolution dynamic MRI. Material/Methods: In a prospective cohort study, the patellar shift, patella rotation and the patellofemoral cartilage contact areas (CCA) of 17 patients with low flexion PFI were analyzed and compared with 17 healthy volunteers, matched via the TEA distance and sex, in unloaded and loaded conditions. MRI scans were carried out for 0°, 15° and 30° knee flexion in a custom-designed knee loading device. To suppress motion artifacts, motion correction was performed using a moiré phase tracking system with a tracking marker attached to the patella. The patellofemoral kinematic parameters and the CCA was calculated on the basis of semi-automated cartilage and bone segmentation and registrations. Results: Patients with low flexion PFI showed a significant reduction in patellofemoral CCA for 0° (unloaded: p = 0.002, loaded: p = 0.004), 15° (unloaded: p = 0.014, loaded: p = 0.001) and 30° (unloaded: p = 0.008; loaded: p = 0.001) flexion compared to healthy subjects. Additionally, patients with PFI revealed a significantly increased patellar shift when compared to volunteers with healthy knees at 0° (unloaded: p = 0.033; loaded: p = 0.031), 15° (unloaded: p = 0.025; loaded: p = 0.014) and 30° flexion (unloaded: p = 0.030; loaded: p = 0.034) There were no significant differences for patella rotation between patients with PFI and the volunteers, except when, under load at 0° flexion, PFI patients showed increased patellar rotation (p = 0.005. The influence of quadriceps activation on the patellofemoral CCA is reduced in patients with low flexion PFI. Conclusion: Patients with PFI showed different patellofemoral kinematics at low flexion angles in both unloaded and loaded conditions compared to volunteers with healthy knees. Increased patellar shifts and decreased patellofemoral CCAs were observed in low flexion angles. The influence of the quadriceps muscle is diminished in patients with low flexion PFI. Therefore, the goal of patellofemoral stabilizing therapy should be to restore a physiologic contact mechanism and improve patellofemoral congruity for low flexion angles. Full article

Background and Objectives: Excessive use of the knee in patients with immature locomotor systems leads to a whole spectrum of morphological changes with possible consequences in adulthood. This study aimed to examine the morphological pattern in magnetic resonance imaging (MRI) that is associated with recurrent pain due to increased physical activity in children. Materials and Methods: This was a retrospective study conducted among pediatric patients treated at the University Children’s Hospital in Belgrade in 2018 and 2019. MRI findings of patients who reported recurrent pain in the knee joint during physical activity and who were without any pathological findings on both clinical examination and knee radiographs were included in the study. Results: MRI findings of 168 patients (73 boys and 95 girls, mean age 14.07 ± 3.34 years) were assessed. Meniscus and cartilage lesions were the most commonly detected morphological findings: meniscus lesions in 49.4%, cartilage ruptures in 44.6%, and cartilage edema in 26.2% of patients. The medial meniscus was more often injured in girls (p = 0.030), while boys were more prone to other joint injuries (p = 0.016), re-injury of the same joint (p = 0.036), bone bruises (p < 0.001), and ligament injuries (p = 0.001). In children older than 15 years, tibial plateau cartilage edema (p = 0.016), chondromalacia patellae (p = 0.005), and retropatellar effusion (p = 0.011) were detected more frequently compared to younger children. Conclusions: Children reporting recurrent knee pain due to increased physical activity, without any detected pathological findings on clinical examination and knee radiography, may have morphological changes that can be detected on MRI. Timely diagnosis of joint lesions should play a significant role in preventing permanent joint dysfunction in the pediatric population as well as in preventing the development of musculoskeletal diseases in adulthood. Full article

A 41-year-old active (exercising >600 min per week) male without a surgical history complained of nine years of intermittent bilateral anterior knee pain after physical activity. He was diagnosed with bilateral chondromalacia (grade IV chondrosis) with plica syndrome, for which he underwent bilateral patella cartilage debridement with medial plica excision (additional removal of lateral retinaculum in the right knee). The patient then performed 12 weeks of an aggressive postoperative rehabilitation program. Each rehabilitation session consisted of disinhibitory modalities (sensory level of transcutaneous electrical stimulation and cryotherapy: focal knee joint cooling and cold-water immersion) and voluntary exercises (aerobic, resistance, and flexibility). During rehabilitation, pain perception, knee joint skin temperature and circumference, and functional outcome measures (Kujala anterior knee pain scale, International Knee Documentation Committee Score, and lower-extremity functional scale) were also recorded. While the patient’s pathology and surgical intervention were not extreme, progressions in the rehabilitation components and functional outcome measures in this clinical case could be used as a future reference for postoperative interventions. Additionally, surgery-induced inflammation seemed to last for four weeks. Full article

Vibroarthrography (VAG) is a non-invasive and potentially widely available method supporting the joint diagnosis process. This research was conducted using VAG signals classified to five different condition classes: three stages of chondromalacia patellae, osteoarthritis, and control group (healthy knee joint). Ten new spectral features were proposed, distinguishing not only neighboring classes, but every class combination. Additionally, Frequency Range Maps were proposed as the frequency feature extraction visualization method. The results were compared to state-of-the-art frequency features using the Bhattacharyya coefficient and the set of ten different classification algorithms. All methods evaluating proposed features indicated the superiority of the new features compared to the state-of-the-art. In terms of Bhattacharyya coefficient, newly proposed features proved to be over 25% better, and the classification accuracy was on average 9% better. Full article

In a retrospective review of 102 patients treated for chondromalacia pa-tellae and patellofemoral pain syndrome/retropatellar dysplasia (PFPS/RPD), the effectiveness of semiflexible foot orthoses was investigated. The combined disorders were diagnosed in 89.3% of the patients. Subjects were 46 women and 54 men, aged 12 to 87 years (mean, 37.9 years; SD, 15.9), who exhibited excessive forefoot varus or rearfoot varus. The initial screening and clinical diagnosis were based on an examination by an orthopedist. Particular attention was directed to patellar crepitation, patellofemoral malalignment, Q-angle measurements, limitation of range of motion, and knee effusion. Patients were evaluated for the onset and duration of patellofemoral pain and degree of knee joint disease. Semiflexible orthoses for each subject were fabricated, based on a clinical lower extremity biomechanical examination. At their follow-up visit, 76.5% were improved and 2% were asymptomatic, showing a significant decrease in the level of pain with orthoses intervention (chi-square P < .001). Although multiple treatment modalities are used for these patients, the results suggest that the use of semiflexible orthoses is significant in reducing symptoms of PFPS/RPD. (J Am Podiatr Med Assoc 93(4): 264-271, 2003) Full article