Two Uncommon Complications Related to Suture Knots After Meniscal All-Inside Suture Repair: A Case Report.

CASE: A 17-year-old male patient suffered a radial lateral meniscus tear and underwent an arthroscopic all-inside suture repair. After 7 months, the patient experienced catching. Magnetic resonance imaging and computed tomography revealed an intra-articular loose body without calcification, which was removed surgically. The excised specimen was histopathologically confirmed to be a necrotic meniscus fragment with a suture knot. In addition, cartilage damage because of suspected impingement by a residual suture knot was observed. After removing the loose body and knot, the patient's symptoms were relieved, and he returned to sports. CONCLUSION: Suture knot-related complications should be considered while performing meniscal repairs.

Editorial Commentary: All-Inside Double-Vertical Cross-Suture is an Effective Technique for Knee Meniscus Radial Tear Repair, but There is No Gold-Standard Evaluation Tool for Evaluating Healing and Function of the Repaired Meniscus.

Treatment of radial tears of the lateral meniscus is challenging. Previous studies after repairing radial tears showed low healing rates. Various suture techniques are now being developed, and biomechanical and clinical studies using these new techniques are underway. Amid development, the all-inside double vertical cross-suture technique seemed to be effective. However, limited evaluations after meniscal repair might not fully reveal whether the repaired meniscus can maintain its function. Because the best single method that can completely evaluate meniscal healing and its function after repair is still lacking, we should introduce various assessments and consider them in a comprehensive way.

The lateral meniscal extrusion after repair with concomitant anterior cruciate ligament reconstruction at a mean follow-up of 3.5 years.

BACKGROUND: A meniscal repair is often performed on radial/flap or longitudinal tears of the lateral meniscus (LM) combined with anterior cruciate ligament reconstruction (ACLR). However, it is unknown if meniscal extrusion changes over time after repair. This study evaluated whether meniscal extrusion of the LM is maintained after repair or progresses with time using magnetic resonance imaging (MRI). METHODS: Among 574 patients who underwent primary anatomic ACLR, 123 patients followed up for more than 2 years were retrospectively analyzed. Forty patients with concomitant radial/flap tears of the LM (group R), 43 with longitudinal LM tears (group L), and 40 with intact LM (group C, matched-control group) were included. Clinical findings (pain, range of motion, swelling, and anterior laxity), lateral joint space on radiograph, and meniscal extrusion on MRI were assessed. Lateral/posterior meniscal extrusions were examined preoperatively, within 3 weeks after surgery, and at the final follow-up, and the absolute values and relative values (the preoperative values as baseline) were assessed respectively. RESULTS: There were no significant differences in the clinical and roentgenographic findings among the groups. No difference was observed in the relative values within 3 weeks after surgery among three groups, although the absolute values were larger in the repaired groups than in group C. At the final follow-up, however, the lateral extrusion in group L had progressed significantly, compared with that in group C (P = 0.033), while no significant difference was detected in the lateral extrusion between groups R and C (P = 0.177). The posterior extrusion in groups R and L had progressed significantly compared with that in group C (P < 0.001). CONCLUSIONS: LM extrusion could not be improved even immediately after meniscal repair, and it progressed laterally and posteriorly for more than 2 years after surgery.

Posterior Root Avulsion Fracture of the Medial Meniscus in a Skeletally Immature Child: A Case Report.

CASE: We describe a rare case of posterior root avulsion fracture of the medial meniscus in an 11-year-old boy. Previous reports have demonstrated delayed diagnosis, but in this case, multiplanar computed tomography (CT) combined with magnetic resonance imaging (MRI) enabled early diagnosis and treatment. Gradual ossification was observed after arthroscopic suture fixation, and meniscal extrusion did not progress. He returned to sports without any symptoms and showed no degenerative changes at 2.5 years postoperatively. CONCLUSION: This is the first case report of early diagnosis and time-course analysis of a rare avulsion fracture, emphasizing the usefulness of CT combined with MRI.

Sequential Changes in Posterior Tibial Translation After Posterior Cruciate Ligament Reconstruction: Risk Factors for Residual Posterior Sagging.

BACKGROUND: Residual posterior sagging may occur after posterior cruciate ligament (PCL) reconstruction (PCLR), yet when it mainly occurs is not fully understood. PURPOSE: To elucidate sequential changes in radiographic posterior tibial translation (PTT) after PCLR. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: The authors retrospectively investigated the radiographic findings from 22 patients who underwent bisocket double-bundle PCLR for isolated PCL injury with at least 2 years of follow-up (mean, 4.5 years; range, 2-10 years). Injury severity was assessed using PTT on lateral radiographs with gravity sag views and was stratified according to side-to-side difference in the tibial-femoral stepoff: grade 1 (<5 mm), grade 2 (5 to <10 mm), or grade 3 (≥10 mm). Measurements were taken preoperatively and then immediately, 3 months, 6 months, 1 year, and ≥2 years postoperatively. The authors also investigated the risk factors for residual posterior sagging, indicated when PTT was ≥5 mm (grade ≥2) at the minimum 2-year follow-up. RESULTS: Preoperatively, 13 patients had a grade 2 injury, and 9 had grade 3 injury. The PTT, restored immediately after PCLR, significantly increased at 3 months (P < .001) but remained unchanged thereafter ≥2 years. There were 7 cases of postoperative PTT ≥5 mm on radiographs. Patients with residual posterior sagging had significantly larger mean PTT than did those without residual posterior sagging at all time points except for immediately postoperatively (preoperatively, 9.1 ± 1.6 vs 12.2 ± 2.3 mm; 3-month follow-up, 2.7 ± 1.6 vs 7.0 ± 1.8 mm; ≥2-year follow-up, 3.4 ± 1.0 vs 6.5 ± 1.4 mm; P < .001 for all). Multivariate logistic regression analysis showed that preoperative grade 3 injury was independently associated with residual posterior sagging (OR, 26.809; 95% CI, 1.257-571.963; P < .001). CONCLUSION: The initially reduced postoperative PTT significantly increased within 3 months using conventional rehabilitation protocols, but no progression was observed up to 4.5 years after PCLR. Preoperative grade 3 injury was independently associated with residual posterior sagging.

Outcomes More Than 2 Years After Meniscal Repair for Longitudinal Tears of the Lateral Meniscus Combined With Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Meniscal function after repair of longitudinal tears of the lateral meniscus (LM) with anterior cruciate ligament reconstruction (ACLR) has not been comprehensively investigated. PURPOSE: To evaluate not only the clinical outcomes and radiographic findings of patients who underwent repair of longitudinal tears of the LM combined with ACLR but also the healing status of the repaired meniscus and changes in chondral status with second-look arthroscopy. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Among 548 patients who underwent primary anatomic ACLR at our institution between 2010 and 2017, 39 who had concomitant longitudinal tears of the LM and underwent repair were studied. During follow-up for more than 2 years, all patients were evaluated clinically (pain, range of motion, swelling, and knee instability) and with imaging (plain radiograph and magnetic resonance imaging [MRI]), and compared with a matched control group (based on age, sex, body mass index, and follow-up period) without any concomitant injuries who underwent ACLR. Measurements on MRI were recorded preoperatively, immediately after surgery, and at final follow-up, and the change in the values over time was assessed. Of the 39 patients in each group, 24 were assessed by second-look arthroscopy with hardware removal 2 years postoperatively. RESULTS: The mean follow-up times of the study and control group were at a mean of 42.4 and 45.4 months, respectively. There were no significant differences in clinical findings, lateral joint space narrowing on radiographs, and chondral status at the lateral compartment between groups, whereas lateral and posterior meniscal extrusion on MRI progressed significantly in the study group (0.43 ± 1.0 mm vs -0.29 ± 1.1 mm, P = .003; 1.9 ± 1.9 mm vs 0.14 ± 1.1 mm, P < .0001, respectively). Second-look arthroscopy revealed complete healing in 12 patients (50%), partial healing in 9 (37.5%), and failure in 3 (12.5%) in the study group, and no new tear in the control group. CONCLUSION: The clinical and imaging outcomes after repair of longitudinal tears of the LM combined with anatomic ACLR were successful and comparable with those after isolated ACLR without any other injuries at 42 months postoperatively, although meniscal extrusion showed progression on coronal/sagittal MRI. Based on the MRI findings and the result that only half of patients achieved complete healing, meniscal function could not be fully restored even after repair. Although degenerative changes were not apparent, longer-term follow-up is needed.

Chronological changes in cross-sectional area of the bone-patellar tendon-bone autograft after anatomic rectangular tunnel ACL reconstruction.

PURPOSE: The purpose of this study was to evaluate the change in cross-sectional area (CSA) of bone-patellar tendon-bone (BTB) autografts up to 5 years after the anatomic rectangular tunnel (ART) anterior cruciate ligament reconstruction (ACLR). The changing pattern in CSA might be a potential indicator of the graft remodeling process. METHODS: Ninety-six (62 males, 34 females, mean age 27.0 years) patients were enrolled in this study with a total of 220 MRI scans after ART BTB ACLR to evaluate the CSA of the ACL autografts. The patients with first time unilateral ACLR that consented to undergo MRI evaluations at postoperative periods were included in this study. Intraoperatively, the CSA of the graft was measured directly using a custom-made area micrometer at the midpoint of the graft. Postoperatively, using an oblique axial slice MRI that was perpendicular to the long axis of the graft, the CSA of the graft was measured with digital radiology viewing program "SYNAPSE" at the midpoint of the graft. The postoperative MRI scans were classified into seven groups according to the period from ACLR to MRI evaluation: Group 0-2 months (m.), Group 3-6 m., Group 7-12 m., Group 1-2 years (y.), Group 2-3 y., Group 3-4 y., and Group 4 y.-. The percent increase of the CSA was calculated by dividing the postoperative CSA by the intraoperative CSA. RESULTS: The postoperative CSA was significantly larger than the intraoperative CSA in each group, with the exception of Group 0-2 m. The mean percent increase of the CSA in Group 0-2 m., 3-6 m., 7-12 m., 1-2 y., 2-3 y., 3-4 y., 4 y.- was 101.8 ± 18.2, 188.9 ± 27.4, 190.9 ± 43.7, 183.3 ± 28.9, 175.2 ± 27.9, 163.9 ± 19.8, 164.5 ± 25.4% respectively. The percent increase in Group 3-6 m., 7-12 m., 1-2 y., 2-3 y., 3-4 y., and 4 y.- was significantly greater than that in Group 0-2 m. CONCLUSIONS: The CSA of the BTB autografts after the ART BTB ACLR increases rapidly by 3-6 months after ACLR, reached a maximum value of 190% at around 1 year, decreases gradually after that, and reaches a plateau at around 3 years. The current study might help clinicians to estimate an individual BTB autograft's remodeling stages when considering returning patients to sports. LEVEL OF EVIDENCE: IV.

Amelioration in Ankle Pain and Improvement in Function After Total Knee Arthroplasty for Ipsilateral Knee and Ankle Osteoarthritis: A Report of Two Cases.

We report 2 cases of ipsilateral ankle and knee osteoarthritis (OA), with the chief complaint being chronic ankle and knee pain. In the first patient, the ankle pain was more severe than the knee pain, whereas the second patient had more severe pain in the knee than in the ankle. In both cases, varus malalignment of the knee and varus tilt of the ankle joint were detected on standing radiographs. The severity of OA was found to be grade 4 in the knee, according to the Kellgren-Lawrence grading system, and stage IIIa in the ankle, according to the modified Takakura ankle OA classification system. Navigation-assisted total knee arthroplasty was performed in both cases, leading to a decreased degree of varus malalignment in the knee and ankle, as well as a significantly improved patient-based outcome in both joints. Correction of malalignment of the ankle by total knee arthroplasty relieved the severe pain and restored optimal function in the ankle without surgical intervention.

Promoting Effect of Basic Fibroblast Growth Factor in Synovial Mesenchymal Stem Cell-Based Cartilage Regeneration.

Synovial mesenchymal stem cell (SMSC) is the promising cell source of cartilage regeneration but has several issues to overcome such as limited cell proliferation and heterogeneity of cartilage regeneration ability. Previous reports demonstrated that basic fibroblast growth factor (bFGF) can promote proliferation and cartilage differentiation potential of MSCs in vitro, although no reports show its beneficial effect in vivo. The purpose of this study is to investigate the promoting effect of bFGF on cartilage regeneration using human SMSC in vivo. SMSCs were cultured with or without bFGF in a growth medium, and 2 × 105 cells were aggregated to form a synovial pellet. Synovial pellets were implanted into osteochondral defects induced in the femoral trochlea of severe combined immunodeficient mice, and histological evaluation was performed after eight weeks. The presence of implanted SMSCs was confirmed by the observation of human vimentin immunostaining-positive cells. Interestingly, broad lacunae structures and cartilage substrate stained by Safranin-O were observed only in the bFGF (+) group. The bFGF (+) group had significantly higher O'Driscoll scores in the cartilage repair than the bFGF (-) group. The addition of bFGF to SMSC growth culture may be a useful treatment option to promote cartilage regeneration in vivo.

Outcomes More Than 2 Years After Meniscal Repair for Radial/Flap Tears of the Posterior Lateral Meniscus Combined With Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Meniscal function after repair of radial/flap tears of the posterior horn of the lateral meniscus (LM) with anterior cruciate ligament reconstruction (ACLR) has not been comprehensively investigated. PURPOSE: To evaluate not only the clinical and radiographic outcomes of patients with repair of radial/flap tears of the posterior LM with ACLR but also the healing status of the repaired meniscus and changes of chondral status with second-look arthroscopy. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: From January 2008 to April 2016, 41 patients of a consecutive series of 505 primary anatomic ACLR cases had a concomitant radial/flap tear of the posterior horn of the LM and underwent side-to-side repair with an inside-out or all-inside technique. All patients were followed for >2 years, evaluated clinically and radiologically (radiograph and magnetic resonance imaging [MRI]), and compared with a control group without any concomitant injuries that underwent ACLR. Of the 41 patients, 30 were assessed by second-look arthroscopy 2 years postoperatively. RESULTS: The mean follow-up times of the study and control groups were 3.4 and 3.9 years, respectively. The study group showed no significant differences in clinical findings, lateral joint space narrowing on radiograph, and coronal extrusion on MRI as compared with the control group, whereas sagittal extrusion on MRI progressed significantly in the study group (1.2 ± 1.5 mm vs 0.32 ± 1.0 mm, P < .001). Eighteen patients (60%) obtained complete healing; 9 (30%) showed partial healing; and 3 (10%) failed to heal on second-look arthroscopy. Changes of chondral status in the femoral condyle showed no significant difference between the groups (P = .29). However, chondral status of the lateral tibial plateau worsened significantly in the study group (P = .0011). CONCLUSION: The clinical and radiographic outcomes after repair of radial/flap tears of the posterior horn of the LM as combined with anatomic ACLR were successful and comparable with those after isolated ACLR without any other injuries at a mean postoperative follow-up of 3.4 years, except for sagittal extrusion on MRI. Chondral lesions of the lateral tibial plateau deteriorated regardless of meniscal healing at 2 years postoperatively. Surgeons should keep in mind that chondral injuries might progress over the midterm.

Discoid lateral meniscal repair without saucerization for adolescents with peripheral longitudinal tear.

Recently, successful clinical outcomes for symptomatic discoid lateral meniscus (DLM) have been reported following partial meniscectomy (saucerization) with repair. In contrast, some studies using radiography and magnetic resonance imaging (MRI) have suggested that function of load transmission might not be appropriately maintained after saucerization with repair. Therefore, in pursuit to uphold load transmission after surgery for DLM, this study tried to preserve the DLM shape to keep the original DLM function. Discoid lateral meniscus repair without saucerization was indicated, with strict criteria, for those who had a painful peripheral longitudinal tear with purely intact body caused after a single traumatic incidence. The repair was performed without saucerization for four adolescents (two males, two females; mean age 16.2 years; three complete types of DLM, and one incomplete type of DLM). Postoperatively, the following were evaluated with radiography and MRI at six, 12, and 24 months after surgery: clinical outcomes, degenerative changes, and morphology of repaired DLM. They all showed good clinical outcomes. Furthermore, no degeneration, deformation, nor extrusion was observed at the two-year follow-up after surgery. For limited cases of DLM, as mentioned above, DLM repair without saucerization can be one treatment option.

Tibial insertion of the anterior cruciate ligament and anterior horn of the lateral meniscus share the lateral slope of the medial intercondylar ridge: A computed tomography study in a young, healthy population.

BACKGROUND: The central intercondylar ridge (CIR) is an anatomical bony landmark that bisects the slope of the medial intercondylar ridge (MIR) between the tibial insertion of the anterior cruciate ligament (ACL) and anterior horn of lateral meniscus (AHLM) and was recently revealed by computed tomography (CT) evaluation corresponding to histologic slices of cadaveric knees. The purpose of this study was to clarify the shape and size of ACL and AHLM tibial insertion in young, healthy knees using the new bony landmark (CIR) and previously reported landmarks. METHODS: The contralateral healthy knees in 34 ACL-reconstructed patients (18 male patients, 16 female patients, mean age: 24.0 years) were scanned by CT. In the reconstructed coronal/sagittal images, bony landmarks of ACL (anterior: anterior ridge, posterior: blood vessel in tubercle fossa, medial: MIR, lateral: CIR) and AHLM (medial: CIR, lateral: bottom of the slope) were plotted for evaluation. The length of sagittal slices and the width in five coronal slices of the insertion were measured. RESULTS: The ACL insertion consistently showed a boot-like-shape adjacent to the square shape of AHLM on three-dimensional imaging. The mean ACL sagittal length was 14.5 ±â€¯1.9 mm, while the mean ACL widths (in mm) from anterior to posterior were 12.7 ±â€¯2.7, 8.1 ±â€¯1.9, 7.9 ±â€¯2.0, 7.5 ±â€¯1.5, and 7.2 ±â€¯1.6, which was highly correlated with the tibial plateau size. CONCLUSIONS: The boot-like-shape of the ACL tibial footprint insertion shared the slope of MIR with the rectangular shape of AHLM in young, healthy knees. This study may provide useful information for safe tibial tunnel creation at the time of ACL reconstruction.

Arthroscopic minimum saucerization and inferior-leaf meniscectomy for a horizontal tear of a complete discoid lateral meniscus: Report of two cases.

INTRODUCTION: Treatment of a horizontal tear of a complete discoid lateral meniscus (DLM) is still controversial. Preserving peripheral rim as a normal shape of the meniscus with single-leaf resection is a conventional treatment, however meniscal function could not be fully restored. PRESENTATION OF CASE: A 28-year old woman and a 34-year old woman experienced knee pain and had restricted knee extension. MRI showed horizontal tears of complete DLM in both patients. Arthroscopic minimum saucerization preserving more than 10 mm peripheral rim and inferior-leaf meniscectomy was performed. Two years after the surgery, the patient had no pain and no restriction of ROM. MRI showed the remaining superior-leaf maintained about half its width and no progression of coronal/sagittal extrusion. DISCUSSION AND CONCLUSION: As resecting more meniscal tissue has been considered to be a cause of degeneration or extrusion of the meniscus, arthroscopic minimum saucerization, preserving more meniscal tissue than standard saucerization, and inferior-leaf meniscectomy can be an alternative treatment option of horizontal tears of complete DLM with satisfying clinical and radiological results.

Incidence, Characteristics and Management of Venous Thromboembolism in Japan During 2011.

BACKGROUND: This study aimed to determine the incidence, characteristics and management of venous thromboembolism (VTE) in Japan during 2011.Methods and Results:A retrospective study assessed responses to a questionnaire regarding treating newly diagnosed VTE at all admitting hospitals throughout Japan during 2011. More individuals were diagnosed with VTE than ever before, with 16,096 cases of diagnosed pulmonary embolism (PE) and 24,538 cases of diagnosed deep vein thrombosis (DVT). Almost half (47.2%) of the PE patients had a relatively mild condition with no right ventricular overload. Similarly, almost half (43.8%) of the DVT patients had a relatively mild condition with isolated calf thrombus. Most of PE patients were treated by anticoagulation, and fewer were treated using thrombolytic agent or inferior vena cava (IVC) filter. CONCLUSIONS: The present study showed a remarkable increase in the incidence of VTE in Japan during 2011. Relatively mild conditions such as non-massive PE and isolated calf DVT were frequently diagnosed. Among PE patients, thrombolytic therapy or IVC filter implantation decreased compared with previous surveys. The appropriate management of isolated calf DVT requires further investigation.

Convolutional auto-encoder for image denoising of ultra-low-dose CT.

OBJECTIVES: The purpose of this study was to validate a patch-based image denoising method for ultra-low-dose CT images. Neural network with convolutional auto-encoder and pairs of standard-dose CT and ultra-low-dose CT image patches were used for image denoising. The performance of the proposed method was measured by using a chest phantom. MATERIALS AND METHODS: Standard-dose and ultra-low-dose CT images of the chest phantom were acquired. The tube currents for standard-dose and ultra-low-dose CT were 300 and 10 mA, respectively. Ultra-low-dose CT images were denoised with our proposed method using neural network, large-scale nonlocal mean, and block-matching and 3D filtering. Five radiologists and three technologists assessed the denoised ultra-low-dose CT images visually and recorded their subjective impressions of streak artifacts, noise other than streak artifacts, visualization of pulmonary vessels, and overall image quality. RESULTS: For the streak artifacts, noise other than streak artifacts, and visualization of pulmonary vessels, the results of our proposed method were statistically better than those of block-matching and 3D filtering (p-values < 0.05). On the other hand, the difference in the overall image quality between our proposed method and block-matching and 3D filtering was not statistically significant (p-value = 0.07272). The p-values obtained between our proposed method and large-scale nonlocal mean were all less than 0.05. CONCLUSION: Neural network with convolutional auto-encoder could be trained using pairs of standard-dose and ultra-low-dose CT image patches. According to the visual assessment by radiologists and technologists, the performance of our proposed method was superior to that of large-scale nonlocal mean and block-matching and 3D filtering.

Worker resignation due to patient nuisance in hospitals: Determinants and prevention.

To investigate determinants and protective strategies for the resignation of health care workers resulting from patient-derived nuisance in medical institutions, we conducted a cross-sectional survey in the 57 hospitals in Mie Prefecture, Japan. A random sampling of 775 employees (physicians, nurses, administrators, and other health care workers) was provided self-administered questionnaires. Among 480 participants who experienced patient-derived nuisance, 132 participants considered resignation as a result, giving an estimated prevalence of 17.1% (95% CI: 14.4%-19.8%) of all respondents. Nonphysical nuisances such as "demand for an unwarranted apology" (OR: 2.57; 95% CI: 1.61-4.12) had higher ORs for considering resignation than other kinds of nuisance. By contrast, OR for the provision of human support by medical institutions was 0.49 (95% CI: 0.28-0.86). Human support was associated with alleviation of the intention to resign.

Post-operative deformation and extrusion of the discoid lateral meniscus following a partial meniscectomy with repair.

PURPOSE: The purpose of this study was to investigate the morphology of the discoid lateral meniscus sequentially following a partial meniscectomy with repair using magnetic resonance imaging (MRI). METHODS: Nine patients with a symptomatic discoid lateral meniscus with a peripheral tear were enrolled in this study, and a partial meniscectomy with repair was performed arthroscopically. An MRI examination was performed 2 weeks after surgery (before weight bearing was permitted) and again 6 months after surgery (when sporting activities could resume). The width, height and distance of the discoid lateral meniscus were measured. The distance was defined as the distance between the edges of the discoid lateral meniscus and the tibia. RESULTS: The width of the anterior, middle and posterior segments significantly decreased from 2 weeks to 6 months after surgery. The height of the middle and posterior segments significantly increased from 2 weeks to 6 months after surgery, whereas the height of the anterior segment did not significantly change. The distance of the anterior, middle and posterior segments significantly decreased from 2 weeks to 6 months after surgery. CONCLUSION: The discoid lateral meniscus exhibited deformation and extrusion from 2 weeks to 6 months after a partial meniscectomy with repair. Therefore, the function of load transmission might not be maintained appropriately after surgery. LEVEL OF EVIDENCE: IV.