Vitamin D as an intervention for improving quadriceps muscle strength in patients after anterior cruciate ligament reconstruction: study protocol for a randomized double-blinded, placebo-controlled clinical trial.

BACKGROUND: The goal of anterior cruciate ligament reconstruction (ACLR) is to restore the preinjury level of knee function to return to play (RTP). However, even after completing the rehabilitation programme, some patients may have persistent quadriceps muscle weakness affecting knee function which ultimately leads to a failure in returning to play. Vitamin D has been long recognized for its musculoskeletal effects. Vitamin D deficiency may impair muscle strength recovery after ACLR. Correcting vitamin D levels may improve muscle strength. METHODS: This is a double-blinded, randomized controlled trial to investigate the effects of vitamin D supplementation during the post-operative period on quadriceps muscle strength in anterior cruciate ligament (ACL)-injured patients. Patients aged 18-50 with serum vitamin D < 20 ng/ml, unilateral ACL injury, > 90% deficit in total quadriceps muscle volume on the involved leg compared with uninvolved leg, Tegner score 7 + , and no previous knee injury/surgery will be recruited. To assess patient improvement, we will perform isokinetic and isometric muscle assessments, ultrasound imaging for quadriceps thickness, self-reported outcomes, KT-1000 for knee laxity, biomechanical analysis, and Xtreme CT for bone mineral density. To investigate the effect of vitamin D status on quadriceps strength, blood serum samples will be taken before and after intervention. DISCUSSION: Patients with low vitamin D levels had greater quadriceps fibre cross-sectional area loss and impaired muscle strength recovery after ACL. The proposed study will provide scientific support for using vitamin D supplementation to improve quadriceps strength recovery after ACLR. TRIAL REGISTRATION: ClinicalTrials.gov NCT05174611. Registered on 28 November 2021.

Mixed Reality and Artificial Intelligence: A Holistic Approach to Multimodal Visualization and Extended Interaction in Knee Osteotomy.

OBJECTIVE: Recent advancements in augmented reality led to planning and navigation systems for orthopedic surgery. However little is known about mixed reality (MR) in orthopedics. Furthermore, artificial intelligence (AI) has the potential to boost the capabilities of MR by enabling automation and personalization. The purpose of this work is to assess Holoknee prototype, based on AI and MR for multimodal data visualization and surgical planning in knee osteotomy, developed to run on the HoloLens 2 headset. METHODS: Two preclinical test sessions were performed with 11 participants (eight surgeons, two residents, and one medical student) executing three times six tasks, corresponding to a number of holographic data interactions and preoperative planning steps. At the end of each session, participants answered a questionnaire on user perception and usability. RESULTS: During the second trial, the participants were faster in all tasks than in the first one, while in the third one, the time of execution decreased only for two tasks ("Patient selection" and "Scrolling through radiograph") with respect to the second attempt, but without statistically significant difference (respectively [Formula: see text] = 0.14 and [Formula: see text] = 0.13, [Formula: see text]). All subjects strongly agreed that MR can be used effectively for surgical training, whereas 10 (90.9%) strongly agreed that it can be used effectively for preoperative planning. Six (54.5%) agreed and two of them (18.2%) strongly agreed that it can be used effectively for intraoperative guidance. DISCUSSION/CONCLUSION: In this work, we presented Holoknee, the first holistic application of AI and MR for surgical planning for knee osteotomy. It reported promising results on its potential translation to surgical training, preoperative planning, and surgical guidance. Clinical and Translational Impact Statement - Holoknee can be helpful to support surgeons in the preoperative planning of knee osteotomy. It has the potential to impact positively the training of the future generation of residents and aid surgeons in the intraoperative stage.

Evaluation of femoral condyle volumes in patients with trochlear dysplasia: a pilot study.

AIM: To examine the volumes of the medial and lateral femoral condyles and the trochlear groove, and to determine their relationship with trochlear dysplasia. MATERIALS AND METHODS: Computed tomography images of the knees of 21 patients with trochlear dysplasia and 18 healthy individuals were analysed retrospectively. According to the modified Dejour classification, the degree of trochlear dysplasia was recorded, such as type A trochlea being low-grade dysplasia and types B, C, and D trochlea being high-grade dysplasia. Volume of the trochlear groove and medial and lateral femoral condyles were calculated using the three-dimensional (3D) volume-rendering method. RESULTS: The volumes of lateral condyle, medial condyle, and trochlear groove were statistically significantly lower in patients with trochlear dysplasia when compared to healthy participants. When compared according to Dejour types, all parameters were statistically significantly lower in both high- and low-grade dysplasia patients (p<0.05). The correlation between femoral condyle volumes and trochlear groove volume was low in the control group, but there was a moderate positive correlation in the patient group (r=0.50-0.75, p<0.05). CONCLUSION: In trochlear dysplasia, the volume of the trochlear groove decreases and hypoplasia may occur in both lateral femoral and medial femoral condyles. Therefore, hypoplasia of only one condyle should not be interpreted as trochlear dysplasia. A holistic approach to patients is required.

Suture-Bridge Fixation of Osteochondral Fractures and Osteochondritis Dissecans in the Knee: Excellent Rates of Early Lesion Stability and Osseous Union.

BACKGROUND: Preservation of articular cartilage in the setting of acute or chronic injury in the adolescent and young adult knee is paramount for long-term joint health. Achieving osseous union, minimizing implant-related injury, and eliminating the need for reoperation for traumatic chondral and osteochondral lesions (OCLs) and osteochondritis dissecans (OCD) remain a challenge for the orthopaedic surgeon. PURPOSE: To evaluate radiographic healing, patient-reported outcomes, and short-term complications after suture-bridge fixation of chondral fragments, osteochondral fractures, and OCD lesions in the knee. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: The study included consecutive patients (38 patients, 40 knees) treated within a single academic sports medicine institution who underwent suture-bridge fixation of an OCL or an OCD lesion of the knee from initiation of the technique in October 2019 through March 2021. The suture-bridge technique entailed bioabsorbable knotless anchors placed on the outside margins of the lesion with multiple strands of hand-tensioned absorbable (No. 0 or No. 1 Vicryl) or nonabsorbable (1.3-mm braided polyester tape) bridging suture. Healing was assessed by radiography and magnetic resonance imaging (MRI), with MRI scans obtained on all OCD lesions and any chondral-only lesions. MRI scans were available for 33 of 40 (82.5%) knees within 1 year of surgery and were evaluated for lesion healing. Complications and rates and timing of return to sport were evaluated. Patient-reported outcomes in the OCD cohort were evaluated with the Knee injury and Osteoarthritis Outcome Score (KOOS) to determine early pain and functional improvement. RESULTS: In total, 33 (82.5%) lesions demonstrated full union, and no lesions failed treatment. MRI assessment of healing (mean, 5.8 months; range, 3-12 months) demonstrated 9 (64.3%) OCD lesions with full union, 5 (35.7%) OCD lesions with stable union, and no OCD lesions with nonunion. Of the OCLs, 17 (89.5%) had full union, 2 (10.5%) had stable union, and none had nonunion. The 7 bony OCLs without an MRI scan demonstrated complete radiographic union. In 30 (75.0%) lesions, patients returned to sports at a mean of 6.5 months (range, 3.8-10.2 months). KOOS Activities of Daily Living, Pain, Quality of Life, and Symptoms scores demonstrated significant improvement from baseline at 6 months and at 1 year. There were 2 (5%) complications, consisting of reoperation for marginal chondroplasty on an otherwise stable lesion, and re-operation for intial un-treated patellar instability, with no reoperations for failure or revision of the suture-bridge construct. CONCLUSION: In this series of OCLs and OCD lesions of the knee, suture-bridge fixation demonstrated excellent rates of MRI and radiographic union and good early outcomes with minimal short-term complications. This technique may be used for lesion salvage as an alternative to metallic and nonmetallic screw/tack constructs in the treatment of these challenging lesions. Longer term follow-up and investigation are warranted.

Application of 3D-Printed Personalized Guide for Lateral Femoral Positioning in Anterior Cruciate Ligament Reconstruction of the Knee.

Objective: This research aims to investigate the effectiveness of 3D computer-assisted customized guided positioning of the lateral femoral tunnel compared to conventional methods for Anterior Cruciate Ligament (ACL) reconstruction surgery. Methods: A total of 80 patients with a complete ACL tear who underwent arthroscopic reconstruction with autologous tendon transplantation (semitendinosus-gracilis tendon) were included in this study. The patients were admitted to our hospital between March 2020 and January 2022 and were randomly divided into two groups: the conventional group (n = 40) and the personalized guide group (n = 40), based on the positioning method. The conventional group underwent ACL restoration using standard surgical techniques, while the personalized guide group opted for the more precise computer-assisted personalized guide method. The lateral femoral tunnel times were compared between both groups. Additionally, the International Knee Documentation Committee (IKDC) and Lysholm scores were assessed, and the lateral femoral location was evaluated using X-ray imaging at 2 weeks postoperatively. Results: After surgery, both groups showed a statistically significant increase (P < .05) in Lysholm and IKDC scores compared to their pre-surgery scores. However, the two groups had no evident difference (P > .05). X-ray evaluation at 2 weeks post-surgery revealed no significant difference between the two groups in NL/ML, AL/BL, α, and ß angles (P > .05). The preparation time for the femoral tunnel was significantly shorter in the personalized guide group (6.18 ± 0.92 min) compared to the traditional group (15.94 ± 3.12 min) (P < .05). Conclusions: The computer-assisted 3D personalized guide positioning method is more effective in locating the lateral femoral tunnel for ACL reconstruction of the knee and can substantially reduce the positioning time. This study provides valuable insights for clinicians when selecting surgical methods.

Predicting Rates of Angular Correction After Hemiepiphysiodesis in Patients With X-Linked Hypophosphatemic Rickets.

PURPOSE: Patients with X-linked hypophosphatemic rickets (XLH) often develop coronal plane knee deformities despite medical treatment. Hemiepiphysiodesis is an effective way to correct coronal plane knee deformities in skeletally immature patients, but a full understanding of the rate of angular correction after hemiepiphysiodesis in XLH patients, compared with idiopathic cases is lacking. METHODS: We retrospectively reviewed charts of 24 XLH patients and 37 control patients without metabolic bone disease who underwent hemiepiphysiodesis. All patients were treated with standard-of-care medical therapy (SOC=active vitamin D and phosphate salt supplementation) in our clinical research center and had a minimum of 2-year follow-up after hemiepiphysiodesis. Demographic data as well as complications, repeat procedures, or recurrence/overcorrection were recorded. Standing lower extremity radiographs were evaluated before the surgical intervention and at subsequent hardware removal or skeletal maturity, whichever came first. Mean axis deviation, knee zone, mechanical lateral distal femoral angle (mLDFA), and medial proximal tibial angle were measured on each radiograph. The rate of angular correction was calculated as the change in mLDFA and medial proximal tibial angle over the duration of treatment. RESULTS: The magnitude of the initial deformity of the distal femur was greater in XLH patients as compared with control for varus (XLH mLDFA 97.7 +/- 4.9 vs. Control mLDFA 92.0 +/- 2.0 degrees) and valgus (XLH mLDFA 78.7 +/- 6.2 vs. Controls mLDFA 83.6 +/- 3.2 degrees). The rate of correction was dependent on age. When correcting for age, XLH patients corrected femoral deformity at a 15% to 36% slower rate than control patients for the mLDFA (>3 y growth remaining XLH 0.71 +/- 0.46 vs. control 0.84 +/- 0.27 degrees/month, <3 y growth remaining XLH 0.37 +/- 0.33 vs. control 0.58 +/- 0.41 degrees/month). No significant differences were seen in the rate of proximal tibia correction. XLH patients were less likely to end treatment in zone 1 (55.0% XLH vs. 77.8% control). XLH patients had longer treatment times than controls (19.5 +/- 10.7 vs. 12.6 +/- 7.0 mu, P value <0.001), a higher average number of secondary procedures than controls (1.33 +/- 1.44 vs. 0.62 +/- 0.92 number of procedures), a higher rate of overcorrection than controls (29.2% vs. 5.4%), and a higher rate of subsequent corrective osteotomy than controls (37.5% vs. 8.1%). There was no significant difference in the rate of complications between groups (8.3% vs. 5.4%). CONCLUSIONS: Patients with XLH undergoing hemiepiphysiodesis have a 15% to 36% slower rate of femoral deformity correction that results in longer treatment times, a higher likelihood to undergo more secondary procedures, and a lower likelihood to reach neutral mechanical alignment. SIGNIFICANCE: This study provides important information to guide the timing and treatment of patients with XLH and coronal plane knee deformities. In addition, results from this study can be educational for families and patients with respect to anticipated treatment times, success rates of the procedure, complication rate, and likelihood of needing repeat procedures.

Associations Between Dietary Intake of Vitamin K and Changes in Symptomatic and Structural Changes in Patients With Knee Osteoarthritis.

OBJECTIVE: To investigate associations of dietary vitamin K intake with changes in knee symptoms and structures in patients with knee osteoarthritis (OA). METHODS: Participants with symptomatic knee OA were enrolled (n = 259) and followed up for 2 years (n = 212). Baseline dietary vitamin K intake was calculated from a validated food frequency questionnaire. Knee symptoms were assessed by using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. Knee cartilage defects, bone marrow lesions, and effusion-synovitis volume were measured from magnetic resonance imaging (MRI) scans. Univariable and multivariable linear regressions were used for analyses. RESULTS: A higher vitamin K intake quartile was significantly associated with a greater decrease in the total WOMAC score and dysfunction score over 24 months. The subgroup analyses showed in patients with severe baseline visual analog scale (VAS) pain that a higher vitamin K intake quartile was associated with more improvement in all WOMAC scores. There were no overall significant associations between vitamin K intake and changes in MRI features. In subgroup analysis, vitamin K intake was negatively associated with changes in tibiofemoral, patellar, and total cartilage defects in participants with a severe baseline radiographic grade and was negatively associated with change in total and patellar cartilage defects in participants with severe baseline VAS pain and in female patients. CONCLUSION: The association of higher vitamin K intake with decreased knee symptoms over 24 months in patients with knee OA suggests that clinical trials examining the effect of vitamin K supplementation for knee OA symptoms are warranted. Whether there is an effect on knee structure is unclear.

Automated Detection Model Based on Deep Learning for Knee Joint Motion Injury due to Martial Arts.

Objective: Develop a set of knee joint martial arts injury monitoring models based on deep learning, train and evaluate the model's effectiveness. Methods: This paper mainly collects knee MRI images of 1546 patients with knee joint martial arts injuries from 2015 to 2020. Through manual annotation, the data set is divided into six categories: meniscus injury, tendon injury, ligament injury, epiphyseal cartilage injury and synovial joint capsule loss. The human knee collaborative MRI image database is established, and the data set is divided into the training and validation sets. And test set. Establish a deep neural network, train the model using the training set and validation set, locate the knee joint injury location, and classify the specific injury type. The model's validity was validated using the test set, and the model's sensitivity, specificity, and mean accuracy for detecting lesions were evaluated. Results: In the test set, the accuracy of meniscus injury, tendon injury, ligament injury, bone and bone cartilage injury and synovial joint capsule injury were 83.2%, 89.0%, 88.0%, 85.9%, 85.6% and 83.5%, respectively, and the overall average accuracy value was 86.0%. The sensitivity and specificity of the model were 91.3% and 87.3%, respectively. Conclusion: The application of the deep learning method in the classification and detection of knee joint martial arts injuries can significantly improve the diagnosis effect, reduce the diagnosis time and misdiagnosis rate, and provide decision support for surgery.

Clinical and Pathogenetic Significance of Amylase Level and Microtomographic Index of Synovial Fluid in Various Joint Lesions.

The aim of the investigation was to study the level of amylolytic activity and microtomographic index of synovial fluid density as well as to substantiate their clinical and pathogenetic significance by identifying correlations with the known informative indicators reflecting characteristic features of the pathological process in various joint diseases. Materials and Methods: Samples of synovial fluid from 95 patients with various joint pathologies at the stage of the disease progression characterized by copious effusion into articular cavities have been examined. Synovial fluid samples obtained by knee arthrocentesis served as a material for the investigation. Conventional methods were used to determine the concentration of uric acid, inorganic phosphorus, total protein, and amylolytic activity level in the selected samples while X-ray density was identified by computed microtomography. Results: All samples of pathological joint fluid have shown a high level of amylolytic activity as compared to the synovial fluid from healthy joints. The relationship between the level of amylolytic activity in synovia and specific joint pathology has been identified. It has also been found that uric acid values, inorganic phosphorus concentrations, and total protein in various types of joint damage may influence X-ray density of the synovial fluid. Correlations between the studied indices have been established. Conclusion: New data on the level of synovia amylolytic activity has been obtained in one non-inflammatory and six different inflammatory diseases. Pathogenically determined correlation between the microtomographic index of synovial fluid density and concentrations of uric acid, inorganic phosphorus, total protein has been confirmed. Specific indicators of X-ray density of synovia in various joint pathologies as well as unidirectional and multidirectional data in comparison with the norm allow us to consider X-ray microtomography as a method that reveals additional details during investigation of synovial fluid density and brings new surrogate markers for the study of pathogenetic mechanisms of the development, differentiation, and treatment of various joint pathologies.

The combined treatment of entrapped Infrapatellar Branch of the Saphenous Nerve after ACL reconstruction: Ultrasound-guided perineural injection and acupotomy.

BACKGROUND: The anterior cruciate ligament (ACL) reconstruction (ACLR) under the arthroscopy is a widespread procedure for ACL rupture, which could stabilize knee and promote recovery. However, one of its complications is the injury of infrapatellar branch of saphenous nerve (IBSN). In traditional Chinese medicine, acupotomy functions via releasing and stripping adhesion tissues. Accordingly, acupotomy is suitable for the treatment of entrapped nerve injury and tissues adhesion. CASE DESCRIPTION: A 14-year-old man, who had ACLR before and returned to normal activity, presented with severe pain after a mild strain two weeks ago. The physical and imaging examinations revealed the compression injury of IBSN. METHODS: We provided the ultrasound-guided perineural injection of 0.4% lidocaine, while it only alleviates the symptoms temporally and partially. Acupotomy using a small needle knife (0.4*40 mm) was performed. RESULTS: The severe pain was immediately resolved. The visual analog pain scale (VAS) decreased from 10 to 1 and return to normal walking. The diameter of IBSN became smaller and the signal of peripheral soft tissue became hypoechoic in ultrasound. CONCLUSION: In this case, the combined treatments of ultrasound-guided perineural injection and acupotomy are thought to be innovative procedures for IBSN entrapment with relative long-lasting therapeutic effects.

A Curious Case of a Wooden Toothpick Inside a Child's Knee: A Case Report.

CASE: A 10-year-old boy presented with vague symptoms, a few days after a nondescript injury to his left knee. History, examination and blood tests, and imaging were unremarkable. Because of his severe pain, we proceeded to arthroscopy. On proceeding to arthroscopy, a wooden toothpick was found inside the knee joint. The wooden toothpick was removed arthroscopically. CONCLUSION: The physicians/surgeons have to be vigilant and should approach holistically toward history and examination of a child presenting with vague signs and symptoms.

A clinical test examination procedure to identify knee compartment overloading: A reliability and validity study using SPECT-CT as reference.

BACKGROUND: Mechanical forces and joint misalignment are considered risk factors for the development of knee osteoarthritis (KOA). Early detection of KOA and distinction between lateral and medial compartment overloading (CO), might be important to inform appropriate preventative interventions. This study evaluated reliability and validity of a test battery consisting of ten clinical tests to predict knee CO. METHODS: Independent observers examined 30 participants with symptoms of KOA. Inter-rater reliability of the ten tests, as well as the anticipated CO based on the whole test battery, was determined. All participants received a SPECT-CT, which served as reference standard for CO. The agreement for CO between SPECT-CT and clinical examination was assessed to determine criterion validity. RESULTS: The Kappa coefficients (k) for the ten individual clinical tests ranged from 0.19 to 0.80. The k for determining CO was 0.52 (95% CI = 0.28-0.76). The agreement for CO between SPECT-CT and clinical examination (i.e. criterion validity) yielded a k of 0.26 (95% CI = -0.06 - 0.58). Logistic regression indicated that valgus alignment was strongly related with lateral CO. No other relationships were found between individual tests and CO. CONCLUSION: Accurate measurement of frontal plane knee angle is important to determine CO. This particular test yielded good reliability, but low validity. Reliability of the nine remaining clinical tests was fair to moderate. Criterion validity of the clinical examination to predict CO was low. Therefore, this test battery in its current form cannot be used in practice to determine CO.

Reliability of knee extensor neuromuscular structure and function and functional tests' performance.

INTRODUCTION: The aim of this study was to evaluate the intra and inter-rater and inter-analyzer reliability of neuromuscular variables and functional tests. METHODS: Cross-sectional crossover design. Two independent raters and analyzers evaluated twenty-two healthy subjects. Knee-extensor strength was assessed from three maximal voluntary isometric contractions. Muscle activation was obtained from the vastus lateralis (VL), rectus femoris (RF), and vastus medialis (VM) muscles. VL and RF muscles' architecture [fascicle length (FL), pennation angle (PA), muscle thickness (MT)] was obtained at rest by ultrasound. The time from five sit-to-stand (STS) trials, and the distance from the 6-min walk test (6MWT) were obtained. Intraclass correlation coefficient was determined and classified as strong (r = 0.75-1.00), moderate (r = 0.40-0.74), and weak (r < 0.40). RESULTS: Strong intra-rater reliability values were observed for strength (r = 0.97), muscle activation [VL (r = 0.91); RF (r = 0.92); VM (r = 0.80)], VL [FL (r = 0.90); PA (r = 0.94); MT (r = 0.99)] and RF [MT (r = 0.85)] muscle architecture, STS (r = 0.95), and 6MWT (r = 0.98). Inter-rater reliability also presented strong values for strength (r = 0.97), muscle activation [VL (r = 0.94); RF (r = 0.79); VM (r = 0.78)], muscle architecture VL [PA (r = 0.81) and MT (r = 0.88)] and RF [MT (r = 0.80)], STS (r = 0.93), and 6MWT (r = 0.98). A moderate correlation VL muscle architecture [FL (r = 0.69)]. Inter-analyzer muscle architecture reliability presented strong VL [FL (r = 0.77); PA (r = 0.76); MT (r = 0.91)] and RF [MT (r = 0.99)]. CONCLUSION: The high intra and inter-rater and inter-analyzer reliability values for most variables is evidence that they can be used for clinical evaluation. Muscle architecture might need a longer training period by different raters and analyzers to increase reliability.

Human osteoclastogenesis in Epstein-Barr virus-induced erosive arthritis in humanized NOD/Shi-scid/IL-2Rγnull mice.

Many human viruses, including Epstein-Barr virus (EBV), do not infect mice, which is challenging for biomedical research. We have previously reported that EBV infection induces erosive arthritis, which histologically resembles rheumatoid arthritis, in humanized NOD/Shi-scid/IL-2Rγnull (hu-NOG) mice; however, the underlying mechanisms are not known. Osteoclast-like multinucleated cells were observed during bone erosion in this mouse model, and therefore, we aimed to determine whether the human or mouse immune system activated bone erosion and analyzed the characteristics and origin of the multinucleated cells in hu-NOG mice. Sections of the mice knee joint tissues were immunostained with anti-human antibodies against certain osteoclast markers, including cathepsin K and matrix metalloproteinase-9 (MMP-9). Multinucleated cells observed during bone erosion stained positively for human cathepsin K and MMP-9. These results indicate that human osteoclasts primarily induce erosive arthritis during EBV infections. Human osteoclast development from hematopoietic stem cells transplanted in hu-NOG mice remains unclear. To confirm their differentiation potential into human osteoclasts, we cultured bone marrow cells of EBV-infected hu-NOG mice and analyzed their characteristics. Multinucleated cells cultured from the bone marrow cells stained positive for human cathepsin K and human MMP-9, indicating that bone marrow cells of hu-NOG mice could differentiate from human osteoclast progenitor cells into human osteoclasts. These results indicate that the human immune response to EBV infection may induce human osteoclast activation and cause erosive arthritis in this mouse model. Moreover, this study is the first, to our knowledge, to demonstrate human osteoclastogenesis in humanized mice. We consider that this model is useful for studying associations of EBV infections with rheumatoid arthritis and human bone metabolism.

[Difference of musculoskeletal ultrasound imaging of focus of knee joint tendon between patients with knee osteoarthritis and healthy subjects].

OBJECTIVE: To observe the imaging features of focus of knee joint tendon in patients with knee osteoarthritis (KOA) by musculoskeletal ultrasound (MSUS) technique. METHODS: One hundred KOA patients and 100 healthy subjects were included. All the KOA patients were palpated by the sequence of foot yangming meridian, foot shaoyang meridian, foot taiyang meridian and foot three yin-meridians, and the focus of knee tendon and its frequency were recorded by MSUS technique. The top-5 focus of knee tendon of KOA patients and the corresponding focus of knee tendon of healthy subjects were selected as the observation sites to compare the differences of thickness of ligament and tendon soft tissue in the extension and flexion positions of the knee joint. RESULTS: The top-5 focus of knee tendon of KOA patients were located in medial inferior patella, medial tibial condyle, inferior patella, Zusanlici and Hedingci. The thickness of ligaments and tendons in extension and flexion positions in KOA patients were thicker than that in healthy subjects (P<0.05). CONCLUSION: The focus of knee joint tendon in KOA patients shows significantly thickened musculoskeletal imaging features.

Diagnostic efficacy of joint ultrasonography, dual-energy computed tomography and minimally invasive arthroscopy on knee gouty arthritis, a comparative study.

OBJECTIVE: This study aimed to investigate the diagnostic performance of minimally invasive arthroscopy for knee gout when comparing with joint ultrasonography and dual-energy computed tomography (DECT). METHODS: From January 2016 to December 2018, 121 inpatients with knee joint swelling and pain were prospectively enrolled, including 63 gout patients and 58 non-gout patients. All patients underwent pre-operative ultrasonography and DECT to evaluate knee joint monosodium urate (MSU) deposits, followed by minimally invasive arthroscopy. The gold-standard for gout diagnosis was defined as the detection of MSU crystals in the synovial fluid under polarizing microscopic or pathological analysis. RESULTS: The diagnostic results of ultrasonic double contour sign, hyperechogenic foci, MSU deposition (detected by DECT), MSU deposition (detected by arthroscopy) and MSU deposition in cartilage (detected by arthroscopy) were significantly associated with that of the gold-standard. Except for hyperechogenic foci, the other four indexes had high sensitivity and specificity (approximately or over 80%) and a large odds ratio (OR) (14.73 to 36.56), indicating good diagnostic performance. Detection of MSU deposition in cartilage by arthroscopy had a good diagnostic agreement with the ultrasonic double contour sign (κ = 0.711, p < 0.001). CONCLUSION: Joint ultrasonography, DECT, and minimally invasive arthroscopy had high sensitivity and specificity for the diagnosis of knee gouty arthritis. Minimally invasive arthroscopy was superior to joint ultrasonography and DECT, which can be a useful supplement for the diagnosis of gout. ADVANCES IN KNOWLEDGE: This is the first study comparing the diagnostic performance for knee gout among the joint ultrasonography, DECT, and minimally invasive arthroscopy.

Patellofemoral Chondropathy Areas in Folk Dancers: An MRI Study.

BACKGROUND: Patellofemoral chondropathy (PFC) is one of the most important causes of patellofemoral pain syndrome. PFC may occur as a result of anatomic reasons such as patellar malalignment and/or increased patellofemoral joint stresses. Most research on this subject has involved sports injuries and anatomic variations. The literature is scarce on PFC related to the dance. METHODS: Fourteen dancers (14 knees, all male) were found to have PFC based on MRI evaluations and clinical examinations between January 2010 and December 2019 (3 dancers were excluded due to prior surgeries of the knee). Age, sex, side of injury, range of motion, Q angle, types of dances, body mass index, and patellar specifics (alta, baja, Wiberg) were recorded for 11 dancers included in the study. We observed PFC at the femoral contact areas (FCA) and patellar contact areas (PCA) of Goodfellow description. RESULTS: Chondral lesions were observed at Gooodfellow areas FCA-3 in 2 dancers, FCA-4 in 5 dancers, PCA-2 in 10 dancers, PCA-3 in 10 dancers, and PCA-4 in 9 dancers. CONCLUSION: Dance styles that include frequent deep flexions and strolling on a flexed knee joint may be risk factors for chondral lesions in the contact area of the femur in male dancers.

Proximal and distal muscle thickness is different in women with patellofemoral pain but is not associated with knee frontal plane projection angle.

OBJECTIVE: The aim of this study was to compare proximal and distal muscle thickness between patellofemoral pain (PFP) and asymptomatic women (CG) and to verify the possible association between morphology and lower limb alignment during single leg-squat. METHODS: Thirty women (PFP, n = 15 and CG, n = 15) performed the following evaluations: (i) muscle thickness of external oblique (EO), gluteus medius (GMed), tensor fascia latae (TFL), peroneus (PER) and tibialis anterior (TA); (ii) knee frontal plane projection angle (FPPA) during single-leg squat. RESULTS: Compared with the CG, PFP showed: (1) smaller GMed (-10.02%; p = 0.04; effect size = 0.82), greater TFL (+18.44%; p = 0.02; effect size = 0.92) and PER (+14.23%; p = 0.02; effect size = 0.87) muscle thickness and greater knee FPPA during single-leg squat (+31.8%; p = 0.04; effect size = 1.12). No differences were observed in EO (+7.17%; p = 0.37; effect size = 0.34) and TA (-1.35%; p = 0.81; effect size = 0.12) muscle thickness. Additionally, we failed to observe significant associations between muscle morphology and knee FPPA in both groups. CONCLUSION: PFP patients showed alterations in proximal and distal muscle thickness, despite the lack of association with poor lower limb alignment. Prospective studies are necessary to determine if differences in muscle morphology are the cause or the consequence of PFP and to confirm the absence of relationship with lower limb alignment.

Revisiting the Genicular Nerve Block: An Up-to-Date Guide Utilizing Ultrasound Guidance and Peripheral Nerve Stimulation - Anatomy Description and Technique Standardization.

BACKGROUND: Over the last decade, several authors have reported that percutaneous peripheral nerve stimulation (PNS) can be used to assist in verifying the position of the procedure needle tip in relation to nerve structures, and that the combined technique using both ultrasound (US) guidance and PNS may serve as a reliable method for confirmation of the correct position of the procedure needle tip. It has also been reported that, when combined with US guidance, PNS may increase the success rate of pain management interventions. OBJECTIVES: The aim of this technical report was to standardize an effective and easy to learn illustrated step-by-step technical approach to nerve identification during US-guided genicular nerve blocks, using percutaneous PNS as a verification instrument for procedure needle tip location. STUDY DESIGN: This technical protocol was developed based on the results of the authors' most recent cadaveric study on the innervation of the knee joint capsule. The technique was developed and tested by 4 different interventionists with different levels of expertise in US-guided procedures. SETTING: The cadaveric study of the knee joint capsule innervation was performed at the laboratory of the Division of Anatomy of one institution. The technical protocol using US and PNS was later developed at the medical simulation center of a different institution. METHODS: A team of anatomists from a division of anatomy of one institution performed the cadaveric study on the innervation of the knee joint capsule. A team of physicians then developed the step-by-step approach to this technical protocol at the medical simulation center of  a different institution. Finally, the illustrated step-by-step approach was tested by 4 different interventionists with different levels of expertise in US-guided procedures (1 beginner-level user; 1 intermediate-level user; 2 expert-level users), using a portable percutaneous PNS and 2 different US transducers at 2 different institutions. RESULTS: This technical protocol was successfully developed based on the results of the cadaveric study on the innervation of the knee joint capsule. Additionally, it was later successfully tested by interventionists with various levels of expertise utilizing different US equipment at separate institutions. LIMITATIONS: By combining US and nerve stimulation, this protocol requires the availability of both US equipment and necessary equipment for nerve stimulation that must all be made available in the sterile field. Another potential disadvantage is that nerve stimulation controls and the US image screen are generally located on 2 separate display panels, which could cause difficulty with visualization and simultaneous calibration for 2 individual devices. CONCLUSIONS: Our illustrated step-by-step technical protocol can be effectively and safely utilized as a reliable method of training, by which physicians with little to moderate US experience can improve their skills in accurately identifying the genicular nerves while performing US-guided examinations with the intent of executing a peripheral nerve block.