Association of Stability and Size of Unhealed Area With Failure After Internal Fixation for Osteochondritis Dissecans Lesions of the Knee: Radiological Evaluation Using Computed Tomography.

BACKGROUND: Open reduction and internal fixation (ORIF) has been widely performed because the osteochondral component of the osteochondritis dissecans (OCD) lesion is the most suitable for reconstructing the joint structure. PURPOSE: To evaluate radiological healing in terms of reconstructed bony structure after ORIF with bone graft by computed tomography (CT), to identify preoperative prognostic factors for failure, and to determine the cutoff value of radiological healing for risk of failure. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A retrospective cohort study of 42 patients (44 knees) who underwent internal fixation with bone graft for OCD lesions of the knee from 2004 to 2018 was conducted. All patients were evaluated 6 months postoperatively, and if not healed 6 months after surgery, they were evaluated by CT periodically thereafter. Radiological healing was judged according to the following 3 criteria: (1) reossification of the OCD lesion, (2) bony continuity between the OCD lesion and basal floor, and (3) reconstructed bony surface of the femoral condyle reconstructed to match the normal joint. Then, the percentage of the radiological healing area was calculated as the ratio of the healing length to the total lesion length. The nonhealing area was calculated by multiplying the sum of the total nonhealing length. Clinical failure was defined as any definitive reoperation for the same OCD lesion, such as fragment excision, or a cartilage restoration procedure. After 6 months, all eligible patients underwent arthroscopy to check for protrusion of the absorbable pin into the joint; the removal of an absorbable pin protruding into the joint was not considered a failure. RESULTS: Clinical failure was recorded for 4 cases (9.1%). The mean overall percentage of the radiological healing area of OCD 6 months after ORIF with bone graft was 79.5% ± 24.4%, and the mean overall nonhealing area at 6 months was 87.8 ± 107.9 mm2. The percentages of radiological healing area of stable (International Cartilage Regeneration & Joint Preservation Society OCD II) lesions and femoral condylar (lateral femoral condyle + medial femoral condyle) lesions were significantly lower than unstable lesions and femoral groove lesions, respectively (P = .01 and P = .03, respectively). On receiver operating characteristic curve analysis, the cutoff points for predicting a significantly increased risk of failure were 33.9% (sensitivity, 100%; specificity, 100%; area under the curve, 1) for the percentage of radiological healing area and 222.9 mm2 (sensitivity, 95%; specificity, 100%; area under the curve, 0.956) for the nonhealing area 6 months postoperatively. CONCLUSION: A stable lesion and a femoral condylar lesion were the predictors of poor radiological healing on CT images 6 months after ORIF with bone graft. The risk of failure was increased significantly in cases with only approximately one-third of the lesion healed or in cases with large nonhealing areas at 6 months postoperatively.

Glenoid rim morphology in young athletes with unstable painful shoulders: primarily painful vs. frankly unstable.

Background: To investigate the characteristics of glenoid rim morphology in young athletes (<40 yr) with unstable painful shoulder. Methods: This was a retrospective case series. The inclusion criteria were as follows: (1) shoulder pain during sports activity, (2) traumatic onset, (3) no complaint of shoulder instability, and (4) soft tissue or bony lesions confirmed on imaging examinations (computed tomography and magnetic resonance imaging). The above-mentioned painful cohort was then compared (in a 2:1 ratio) to a match-paired control group of patients with similar demographics but with frank anterior glenohumeral instability as defined by imaging and physical findings. The pain (not apprehension) was reproduced during the anterior apprehension test in supine position and relieved by relocation test in all patients. Glenoid rim morphology, bone union in shoulders with a fragment-type glenoid, glenoid defect size, bone fragment size, medial displacement of bone fragments (MDBF), and medial distance of erosion (MDE) were compared between painful shoulders and unstable shoulders. Results: There were 79 painful shoulders and 165 unstable shoulders. The glenoid rim morphology was normal in 33 shoulders, erosion-type in 15 shoulders, and fragment-type in 31 shoulders among painful shoulders, whereas the respective shoulders were 19, 33, and 113 among unstable shoulders (P < .001). Bone union was complete in 15 shoulders, partial in 14 shoulders, and nonunion in 2 shoulders among painful shoulders, whereas the respective shoulders were 43, 31, and 39 among unstable shoulders (P = .001). The mean glenoid defect size was 6.0 ± 7.2% and 12.7 ± 7.4%, respectively (P < .001), and the mean bone fragment size was 5.8 ± 6.4% and 5.4 ± 4.6%, respectively, (P = .591). The mean MDBF was 1.4 ± 1.5 mm and 3.0 ± 2.2 mm, respectively (P < .001), and the mean MDE was 2.3 ± 1.2 mm and 5.2 ± 2.4 mm, respectively (P < .001). In shoulders with a smaller glenoid defect (<13.5%), the prevalence of shoulders with MDBF (<2 mm) and shoulders with MDE (<2 mm) was more frequent in painful shoulders. On the other hand, in shoulders with a larger glenoid defect (≥13.5%), erosion-type glenoid, nonunion in fragment-type glenoid and bone fragment smaller than 7.5% was not recognized in painful shoulders. Shoulders with MDBF (<2 mm) were significantly more frequent in painful shoulders (P = .009). Conclusions: In painful shoulders normal or erosion-type glenoid was predominant, and glenoid defect size was significantly smaller than unstable shoulders. On the other hand, a large bone fragment (≥7.5%) remained and united completely or partially in all shoulders with a larger glenoid defect (≥13.5%). Bone union was obtained within 2 mm from the articular surface in most of them.

Clinical outcomes after repair of an isolated radial tear in the middle segment of the lateral meniscus - All-inside suture repair vs trans-capsular suture repair.

Background/objective: For radial tears, all-inside suture (AIS) repair was clearly biomechanically superior, compared to conventional trans-capsular suture (TCS) repairs. However, clinical comparative studies of these two repairs techniques have not to be performed. Therefore, the aim of this study was to compare the clinical outcomes after AIS repair and TCS repairs for isolated radial tear at middle segment of lateral meniscus (RTMLM) in stable knees of young athletes. Methods: Twenty-six athletes (mean age, 19.1 years) underwent AIS repair with the double horizontal suture technique, using SutureLasso™ (Arthrex, Naples, FL) for isolated RTMLM (AIS group), and 20 athletes (mean age, 19.0 years) underwent inside-out repair, one of TCS repairs, with tie-grip suture technique (TCS group). All athletes were assessed for preoperative and two-year postoperative Knee injury and Osteoarthritis Outcome Score (KOOS). At six-month after repair, the lateral meniscal extrusion on mid-coronal plane on MRI and healing status on second-look arthroscopy were also evaluated in all patients. Results: In both groups, KOOS improved to either good or excellent postoperatively, while complete healing was found in only 23 and 25% at second-look arthroscopy. We identified no group-dependent differences in KOOS or healing status on arthroscopy. However, a close examination of failure rates revealed significant lower rates in AIS group relative to that of TCS group (p = 0.048). Moreover, the change from preoperative to postoperative lateral meniscal extrusion in AIS group was significantly smaller than that in TCS group (p = 0.038). Conclusions: AIS and TCS repairs for RTMLM were comparable in providing satisfactory clinical results with low rates of complete healing on arthroscopy. However, AIS repair could have lower failure rate of healing on arthroscopy and minimize postoperative lateral meniscal extrusion more effectively than TCS repair on MRI.

Rectangular bone-patellar tendon bone grafts reduce early graft failure in chronic ACL-Deficient knees.

BACKGROUND: The aim of this study was to assess early graft failure after anterior cruciate ligament (ACL) reconstruction according to chronicity of ACL deficiency (ACLD) and clarify predisposing factors. METHODS: A total of 731 patients who underwent anatomic ACL reconstruction were divided into 3 groups based on chronicity of ACLD: <6 months (Group 1), 6 months to 2 years (Group 2), and >2 years (Group 3). Types of ACL grafts used included single-bundle hamstring tendon (HT), multiple-bundle HT, and rectangular bone-patellar tendon-bone (BTB) grafts. Preoperatively and immediately postoperatively, lateral radiographs in full extension were taken to examine anterior tibial subluxation (ATS). All ACL grafts were evaluated by MRI at 6 months to identify graft failure. The group with the highest failure rate was further examined to compare possible risk factors between the intact and failure subgroups, followed by multivariate logistic regression analysis to identify predisposing factors. RESULTS: Early graft failure on MRI without any episode of postoperative trauma was observed in 7 (1.4%), 2 (1.8%), and 11 (9.2%) patients in Groups 1, 2, and 3, respectively, with a significantly higher rate in Group 3 (P < 0.001). Of the 119 patients in Group 3, significant differences were observed between intact and failure subgroups with regard to surgical procedure (P = 0.03), chondral lesions (P < 0.01), and preoperative ATS (P < 0.01). Multivariate logistic regression analysis revealed that surgical procedures (odds ratio, 3.8; 95%CI, 1.16-12.59) and preoperative ATS (odd ratio, 2.4; 95%CI, 1.26-4.38) were predisposing factors of early graft failure. CONCLUSION: Patients with ACLD for >2 years experienced early graft failure with an incidence rate of 9.2%. Predisposing factors of early graft failure in these patients included the use of single-bundle HT grafts and preoperative ATS. The use of rectangular BTB grafts resulted in a lower graft failure rate. STUDY DESIGN: Case Series.

Changes in patellar height after anatomical ACL reconstruction with BTB autograft with a focus on patellar tendon removal volume.

BACKGROUND: Although anatomical anterior cruciate ligament reconstruction (ACLR) can provide satisfactory outcomes, little is known about how this procedure impacts patellar height. Since harvesting bone-patellar tendon-bone (BTB) autografts is a potential risk factor for decreased patellar height, we examined changes in patellar height after anatomical ACLR with BTB autograft with a focus on the size of the harvested graft. METHODS: Subjects were 84 patients (49 males, 35 females; mean age, 23 years) who underwent primary anatomical ACLR with central third BTB autograft. Preoperative to postoperative Caton-Deschamps index (CDI) ratio was calculated using lateral knee radiographs before and 6 months after surgery. The length and cross-sectional area (CSA) of the graft were measured intraoperatively, and the CSA of the contralateral patellar tendon was measured by ultrasound 6 months postoperatively. The difference in graft CSA relative to the contralateral tendon CSA, expressed as a percentage (gCSA:ctCSA percentage), was also calculated. RESULTS: Patellar height decreased slightly after surgery (preoperative CDI: 0.856 ± 0.113; postoperative CDI: 0.841 ± 0.113), with a mean difference between preoperative and postoperative CDIs of -0.015 (range: -0.293 to 0.101). Although the CDI of male subjects significantly decreased after surgery (preoperative: 0.852 ± 0.117; postoperative: 0.827 ± 0.115), no significant changes were noted in female subjects (preoperative: 0.862 ± 0.108; postoperative: 0.861 ± 0.108). Graft length and CSA did not significantly impact the CDI ratio (r = -0.138 and r = -0.038, respectively). Moreover, no significant relationship was observed between the gCSA:ctCSA percentage and CDI ratio (r = 0.118). CONCLUSIONS: Although patellar height slightly, but significantly, decreased at 6 months after anatomical ACLR with BTB autograft, it was not affected by the length and CSA of harvested grafts. The decrease in postoperative patellar height was observed only in male subjects, suggesting the potential importance of sex differences in soft tissue healing during the postoperative period.

The Wound Dressing Influenced Effectiveness of Cryotherapy After Anterior Cruciate Ligament Reconstruction: Case-Control Study Comparing Gauze Versus Film Dressing.

Purpose: To compare the clinical effectiveness of cryotherapy after anterior cruciate ligament reconstruction using 2 different wound dressings, conventional postoperative gauze dressings and polyurethane semipermeable transparent film dressings. Methods: In total, 60 patients who had undergone arthroscopic anterior cruciate ligament reconstruction with an autogenous patellar tendon were assigned to 2 groups. The surgical wound was covered with 5 sheets of gauze with an elastic bandage (control group) in 30 patients and film dressing was used (film group) in the remaining 30 patients. Silicone drainage catheters were inserted at the intercondylar notch, beside the distal outlet of the tibial tunnel for 2 days. After 1 hour of cooling using the device, the knee was chilled with an ice bag every 2 hours until the next morning. The severity of pain was evaluated by the number of times an analgesic, 50 mg of diclofenac sodium suppositories, had to be administered in the 24 hours after surgery. The amount of drainage during the following 2 days, the range of motion at 21 days, the change of hemoglobin concentration at 1 and 7 days, and C-reactive protein (CRP) at 1 and 7 days were examined. Results: The number of patients who used an analgesic was 18 in the control group and 7 in the film group (P = .003). The amount of drainage was 165.2 ± 72.9 mL in the control group and 289.7 ± 77.6 mL in the film group (P < .001). The postoperative CRP value was 0.77 ± 0.65 mg/dL at 1 day in the control group and 0.39 ± 0.42 mg/dL in the film group (P = .009). No statistical difference was seen for hemoglobin concentration at 1 or 7 days, CRP at 7 days or range of motion at 21 days. Conclusions: In this study, we found that film dressing enhanced the effect of cryotherapy with respect to pain control, wound drainage, and inflammation immediately after surgery compared with traditional gauze dressing with elastic wrap. Level of Evidence: III, case-control study.

Posterior Ankle Impingement Caused by Hyaline-Like Cartilage Generation in Ballet Dancers-A Report of 2 Cases.

Posterior ankle impingement syndrome is mainly seen in ballet dancers and frequently associated with specific movements in ballet such as pointe and demi pointe in which the whole-body weight is applied to the maximally plantar flexed ankle. We performed arthroscopic debridement for 2 dedicated ballet dancers on the intervening soft tissue causing posterior ankle impingement syndrome (PAIS). In both cases, T2-weighted magnetic resonance imaging (MRI) revealed low-signal intensity of meniscus-like soft tissue without abnormal osseous findings, connecting from the posterior side of the talus to Kager's fat pad. To examine the intervening soft tissue in detail, we performed histological evaluation by hematoxylin and eosin staining, Safranin O fast green staining, and immunohistochemistry for type I collagen and type II collagen. Hematoxylin and eosin staining showed that there was cartilage-like tissue including chondrocyte-like cells in contact with fibrous tissue. The extracellular matrix in the cartilage zone was consistently stained by Safranin O staining and type II collagen without any staining with type I collagen. These findings suggested that the meniscus-like soft tissue appearing as low-signal intensity on MRI at the posterior side of talus included hyaline-like cartilage. To the extent of our knowledge, these were rare cases of hyaline-like cartilage generation causing PAIS in ballet dancers, which might be associated with ballet specific movements resulting in chondrogenesis.

Isolated peripheral longitudinal tears in the anterior-middle segment of medial meniscus among young soccer players: A case series.

INTRODUCTION: There was little information about the isolated medial meniscal tears in the anterior-middle segment. This study aimed to report the infrequent cases of the isolated medial meniscal tears in the anterior-middle segment related to kicking motion among young soccer players with a short-term postoperative outcome. PRESENTATION OF CASE: In the retrospective review of the surgical records from 2000 to 2018, there were 15 cases with the corresponding tear. They were all young male soccer players with a mean age of 16.7 years (range: 10-23 years). The cause of injury was kicking motion during playing soccer in all the patients. The most frequent symptom was locking in 80% of the cases. In the arthroscopic evaluation, all the cases presented with a longitudinal (bucket-handle) tear in the anterior-middle segment in the peripheral zone with a length of 25 to 30 mm, while the posterior segment and the cruciate ligaments were intact. Meniscal repair was performed for all the cases. At one year, all the patients could return to play soccer with a pre-injury level without any symptoms. In the second-look arthroscopy at six months among four cases, all meniscal tears healed completely. DISCUSSION AND CONCLUSION: Clinicians should be aware of the possibility of isolated peripheral longitudinal tear in the anterior-middle segment of the medial meniscus, which is related to the kicking motion among young soccer players and mainly causes locking.

Second-look arthroscopy after double-bundle posterior cruciate ligament reconstruction: Effect of patient age.

PURPOSE: Second-look arthroscopy is invasive but still one of the most useful postoperative evaluation methods since graft morphology including graft tension, graft tear, and synovial coverage can be directly evaluated. However, only a few studies have evaluated transplanted posterior cruciate ligament (PCL) grafts. This study aimed to clarify the PCL graft morphology and chondral damages at second-look arthroscopy after double-bundle PCL reconstruction (PCLR) and to investigate the effects of patient age on these arthroscopic findings. METHODS: This study retrospectively included 26 patients who underwent second-look arthroscopy at the time of hardware removal 14 months after double-bundle PCLR for isolated PCL injury from January 2007 to December 2020. The patients were divided into two groups: group A, 39 years or younger (n = 14); and group B, 40 years or older (n = 12). At second-look arthroscopy, the grafts were evaluated based on tension (taut, graft tension as tense as a normal PCL; lax, graft tension looser than a normal PCL, unclassified, completely torn graft), tear (one or more tendon strands torn), and synovial coverage (good, synovial coverage greater than 80% around the graft; fair, synovial coverage greater than 50%; and poor, synovial coverage less than 50%). The chondral damages were evaluated using the Outerbridge classification system. Radiographic posterior tibial translation with gravity sag view as well as clinical outcomes were also evaluated. RESULTS: Anterolateral (AL) graft tension was lax in 8% of the patients, whereas posteromedial (PM) graft tension was lax or unclassified in 24% (p = 0.043). Graft tear was observed only in the PM graft of 19% patients (p = 0.022). Synovial coverage of AL grafts was good or fair in all cases, whereas that of PM grafts was poor in 28% cases (p < 0.001). Regarding the effect of patient age, the synovial coverage of PM grafts was significantly poorer in group B (p = 0.033), but no statistical difference in graft tension or tear was found. The chondral damages were significantly advanced in group B (p ≤ 0.01), except for the trochlear groove and lateral femoral condyle. No patients had residual subjective posterior instability, knee swelling, or loss of extension exceeding 5° or flexion exceeding 10°. All patients had improved from grade II or III preoperatively to grade I or grade II in the posterior drawer test. The posterior tibial translation significantly improved from 10.0 ± 3.6 mm preoperatively to 3.6 ± 2.1 mm at second-look arthroscopy. No significant differences in the postoperative clinical outcomes were observed between the two groups. CONCLUSION: The morphology of the PM grafts at second-look arthroscopy after double-bundle PCLR was poorer than that of the AL grafts. Patient age negatively affected the postoperative graft synovial coverage and chondral status but did not affect the clinical outcomes.

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.

Tunnel Enlargement Correlates With Postoperative Posterior Laxity After Double-Bundle Posterior Cruciate Ligament Reconstruction.

BACKGROUND: There exists little information in the relevant literature regarding tunnel enlargement after posterior cruciate ligament (PCL) reconstruction (PCLR). PURPOSE: To sequentially evaluate tunnel enlargement and radiographic posterior laxity through double-bundle PCLR using autologous hamstring tendon grafts. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We prospectively analyzed 13 patients who underwent double-bundle PCLR for an isolated PCL injury. Three-dimensional computed tomography images were obtained at 3 weeks, 6 months, and 1 year postoperatively, and the tunnel enlargement was calculated by sequentially comparing the cross-sectional areas of the bone tunnels. We also sequentially measured radiographic posterior laxity. The correlation between the tunnel enlargement ratio and the postoperative increase in posterior laxity was evaluated. RESULTS: The cross-sectional area at the aperture in each tunnel significantly increased from 3 weeks to 6 months (P < .003), but it did not continue doing so thereafter. The 6-month tunnel enlargement ratios of the femoral anterolateral tunnel, the femoral posteromedial tunnel, the tibial anterolateral tunnel, and the tibial posteromedial tunnel were 31.6% ± 23.5%, 90.3% ± 54.7%, 30.5% ± 26.8%, and 49.6% ± 37.0%, respectively, while the corresponding ratios at 1 year were 28.1% ± 19.8%, 83.1% ± 56.9%, 26.8% ± 32.8%, and 47.6% ± 39.0%, respectively. The posterior laxity was 9.0 ± 4.0 mm, -1.5 ± 2.3 mm, 3.4 ± 2.0 mm, and 3.9 ± 1.9 mm, preoperatively, immediately after surgery, 6 months and 1 year postoperatively, respectively. From the immediate postoperative period, the posterior laxity significantly increased at 6 months postoperatively (P < .001), but it did not thereafter. The postoperative increase in posterior laxity had a significant positive correlation with the anterolateral tunnel enlargement ratio in both femoral and tibial tunnels at 6 months (ρ = 0.571-0.699; P = .011-.041) and 1 year (ρ = 0.582-0.615; P = .033-.037). CONCLUSION: Tunnel enlargement after PCLR mainly occurred within 6 months, with no progression thereafter. The anterolateral tunnel enlargement positively correlated with postoperative increase in posterior laxity.

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.

Comprehensive study of insecticides in atmospheric particulate matter in Hanoi, Vietnam: Occurrences and human risk assessment.

Air pollution is the most serious environmental issue in Vietnam, particularly in big cities. Air pollutants that are set as environmental standards are regularly monitored by the public institutions. Whereas, environmental data on organic micro-pollutants in atmospheric particulate matters (APMs) is limited, including PAHs and POPs. Although massive pesticides are used in big cities, their data in APMs in Vietnam is very scarce. In order to elucidate their occurrence in the ambient air in Hanoi and their health effects, we surveyed 107 insecticides in APMs by a novel target screening method using LC-QTOF-MS-SWATH. A total of 19 insecticides were detected in the dry and the rainy seasons. Among them, 16 substances are, to our knowledge, reported for the first time in the literature. Their total concentrations varied from 0.47 to 27.0 ng m-3 (median, 3.6 ng m-3), detection frequencies of 12 compounds are higher than 42%, and the number of insecticides detected per each sample ranging from 5 to 13 (median, 9). Total concentrations in the dry season were generally higher than in the rainy season, and concentrations at night were higher than daytime in both seasons. The level of insecticides depends not only on the season, but also on its physicochemical properties, its application conditions, and the meteorological conditions. Their emission sources could be related to agricultural usage, floricultural activities, and pest control in houses. The total maximum daily intake (DIair) through inhalation for adults and children were 2.39E-05 mg kg-1 d-1 and 2.98E-05 mg kg-1 d-1, respectively. The highest Hazard Quotients (HQs) were 1.34E-03 and 3.37E-03, and the highest Hazard Indices (HIs) were 2.71E-03 and 6.33E-03 for adults and children, respectively. All values of HQs, and HIs of insecticides were less than 1, indicating that health risk would be negligible.

Preoperative quadriceps strength as a predictor of return to sports after anterior cruciate ligament reconstruction in competitive athletes.

OBJECTIVES: To determine whether preoperative quadriceps strength predicts the likelihood of return to sports (RTS) following anterior cruciate ligament reconstruction (ACLR) in competitive athletes. DESIGN: Case-control study. SETTING: Single-center. PARTICIPANTS: A total of 221 competitive athletes who underwent primary ACLR were followed and divided into RTS (n = 177) and non-RTS (n = 44) groups based on self-reported sports activities at one year postoperatively. MAIN OUTCOME MEASURES: Isokinetic quadriceps strength tests were performed preoperatively and at six months and one year postoperatively, and the quadriceps index (QI) was calculated. Functional performance was evaluated by the single-leg hop (SLH) test at six months postoperatively. RESULTS: Preoperative QI significantly predicted the likelihood of RTS (odds ratio, 1.68 per 10-unit increase; P < 0.001), with a preoperative QI cut-off of 66% (AUC: 0.74; sensitivity: 68.9%; specificity: 77.3%). Subjects with a preoperative QI < 66% had a significantly lower postoperative QI, SLH, and rates of RTS compared to those with a higher preoperative QI (P < 0.01). CONCLUSIONS: Preoperative quadriceps strength could predict the likelihood of RTS following ACLR, and a preoperative QI < 66% was associated with a greater risk of unsuccessful RTS at one year postoperatively. Preoperative QI should be evaluated as a predictor of RTS.

A 3-Species Aquatic Community Model for Ecological Risk Assessment Using Basic Ecotoxicity Data.

A simplified ecosystem model, the Aquatic Tritrophic Ecological Risk Assessment Model (A-TERAM), for the ecological risk assessment of chemicals is presented. The A-TERAM comprises a linear grazer food chain with 3 trophic levels (the algae-Daphnia-fish system). The model simulates the seasonal patterns of abundance at each level observed in the field, and it translates the direct toxic effects of chemicals on algae or Daphnia to implications for fish via ecological interactions; thus, the A-TERAM evaluates ecological risk in terms of the annual population growth rate of fish. The model also incorporates toxicokinetics for fish. The minimum input data required for the A-TERAM are basic ecotoxicity endpoints (algal growth inhibition median effect concentration [EC50] or no-observed effect concentration, Daphnia immobility EC50, and fish acute mortality median lethal concentration); however, additional ecotoxicity data (Daphnia reproduction test, fish early life test, and fish reproduction test) are also relevant for improving simulations. Comparisons made across 496 chemicals (255 nonagricultural chemicals and 241 agrochemicals) indicated that the A-TERAM, in comparison with the conventional predicted-effect concentration/predicted-no-effect concentration method, tended to evaluate higher risk to chemicals that are highly bioaccumulative and toxic to fish by 2 orders of magnitude at the largest but lower or comparable risk to chemicals that are toxic only to algae or Daphnia. Environ Toxicol Chem 2020;39:1086-1100. © 2020 SETAC.

Osteochondritis Dissecans of the Knee: Short-Term Outcomes of a Hybrid Technique to Restore a Partially Salvageable Progeny Fragment.

OBJECTIVE: This retrospective case series describes a hybrid fixation technique and determines the clinical outcomes, knee function, and activity level of patients at short-term follow-up. DESIGN: Seventeen patients (18 knees) with unstable osteochondritis dissecans (OCD) lesions involving the knee were treated with a hybrid fixation technique in which the salvageable fragment was fixed and osteochondral autograft transplantation system (OATS) was used for the unsalvageable fragment. Thirteen lesions involved the medial femoral condyle, 4 involved the lateral femoral condyle, and 1 involved the patella. Mean patient age was 17 years (range 12-28 years). All lesions were International Cartilage Repair Society (ICRS) grade III or IV. The patients were prospectively followed postoperatively. Outcome measures included the International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score (KOOS), and the Tegner activity scale. RESULTS: At mean follow-up of 36 months (range 24-67.2 months), the mean postoperative KOOS scores, given as mean (SD), were as follows: Quality of Life (QoL) 91.1 (17.0), Activities of Daily Living (ADL) 99.5 (1.5), Sport 94.5 (11.2), Pain 97.4 (5.8), and Symptoms 95.9 (6.5). Mean IKDC score was 96.2 (7.0). There was no significant difference between mean preinjury (7.95, SD = 1.1) and mean postoperative (7.45, SD = 1.5) Tegner scores (P = 0.363). The mean Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was 87.5 at a mean 7.8 months (range 3-18 months) postoperation. There were no reported complications. CONCLUSION: The results of this case series suggest that patients with partially salvageable OCD lesions involving the knee can have positive short-term outcomes and can expect a low complication rate when treated with a hybrid technique of fixation with osteochondral autograft transfer.

Importance of functional performance and psychological readiness for return to preinjury level of sports 1 year after ACL reconstruction in competitive athletes.

PURPOSE: This study aimed to identify independent predictive factors for return to sports (RTS) after anterior cruciate ligament (ACL) reconstruction in competitive-level athletes and to determine optimal cut-off values for these factors at 6 months after surgery. METHODS: A total of 124 competitive athletes (50 males and 74 females; mean age, 17.0 years; preinjury Tegner activity scale > 7) who underwent primary ACL reconstruction were enrolled. Assessments at 6 months after surgery consisted of knee functional tests [quadriceps index, hamstrings index, and single-leg hop for distance (SLH)] and 2 self-report questionnaires [IKDC subjective score and ACL-Return to Sport after Injury scale (ACL-RSI)]. At 1 year after surgery, athletes were classified into the RTS group (n = 101) or non-RTS group (n = 23) based on self-reported sports activities. After screening possible predictive factors of RTS, multivariate logistic regression and receiver operating characteristic curve analyses were performed to identify independent factors. RESULTS: Multivariate logistic regression analysis identified SLH (odds ratio, 2.861 per 10 unit increase; P < 0.001) and ACL-RSI (odds ratio, 1.810 per 10 unit increase; P = 0.001) at 6 months as independent predictors of RTS at 1 year after surgery. Optimal cut-off values of SLH and ACL-RSI were 81.3% (sensitivity = 0.891; specificity = 0.609) and 55 points (sensitivity = 0.693; specificity = 0.826), respectively. CONCLUSION: In competitive athletes, SLH < 81% and ACL-RSI < 55 points at 6 months after surgery were associated with a greater risk of unsuccessful RTS at 1 year after surgery. SLH and ACL-RSI at 6 months could serve as screening tools to identify athletes who have difficulties with returning to sports after ACL reconstruction. LEVEL OF EVIDENCE: III.

Autologous Osteochondral Transplantation in Full-thickness Patella Chondral Lesion: A Case Series.

PURPOSE: Autologous osteochondral transplantation (AOT) in the focal cartilage lesion of the patella has been reported with less successful results compared with other sites. The purposes were to investigate the clinical outcomes of AOT for focal patellar chondral lesion without patellofemoral instability. METHODS: Between 2001 and 2007, six patients (five males and one female) with a focal patellar cartilage lesion without patellofemoral malalignment and instability were treated with AOT. The mean age was 38 (27-51) years. Intraoperatively, the size and location of lesion were assessed by international cartilage repair society classification. Lysholm score was investigated preoperatively, at 6 months, 1- and 2-year, and final follow-up. Mean follow-up period was 51 months (24-101). Transplanted grafts were evaluated by magnetic resonance imaging (MRI) and second-look arthroscopy. RESULTS: The mean size was 133mm2(78-225). All six cases improved at final follow-up (Lysholm score 79-100). Although immediate pain relief obtained in four cases, severe pain was persistent in remaining two cases during the 1styear and gradually relieved by 2 years following surgery. The size of these two cases was significantly larger (over 170 mm2) than that of four cases (100 mm2 in average) (P<0.05), and their locations were apart from center of the patella inspite of four cases localized centrally (P<0.05). Repaired cartilage did not show any difference by MRI and arthroscopically. CONCLUSION: AOT in focal patellar chondral lesions without patellofemoral malalignment showed excellent results. In cases of large off-centeredlesions, however, it took longer for pain relief following AOT.

Broad-scale effect of herbicides on functional properties in benthic invertebrate communities of rivers: An integrated analysis of biomonitoring and exposure evaluations.

We conducted a broad-scale ecological effect assessment of agricultural chemicals where we combined biomonitoring databases of riverine invertebrate communities with predictions of environmental concentrations of chemicals, based on an exposure evaluation model for Japanese rivers. One of the difficulties of broad-scale assessment arises from the use of biomonitoring databases for which the monitoring sites are often spread across different geographic regions, with varying species compositions and heterogeneous environmental factors. This problem was circumvented using a trait-based approach, which extracts patterns of ecological properties of species response to changes in either chemical concentration or environmental factors. We identified groups of species that had particular trait categories that were negatively correlated with herbicide pollutants (the predicted concentration divided by the acute toxic concentration). Numerical abundances of species groups classified by trait categories had more sensitive responses to herbicide pollutants than total species abundance. However, a finding that trait diversity and species diversity indexes in the communities examined did not change with herbicide pollutants means that the two indexes showed resistance to chemical stresses. We inferred that the reason for the greater resistance in terms of trait and species diversity was that compositional changes of species caused by increasing herbicide pollutions were simply a shift from communities composed of susceptible species to those composed only of tolerant species.

Significant anterior enlargement of femoral tunnel aperture after hamstring ACL reconstruction, compared to bone-patellar tendon-bone graft.

PURPOSE: This study aimed to retrospectively compare the enlargement and migration of the femoral tunnel aperture after anatomic rectangular tunnel anterior cruciate ligament (ACL) reconstruction with a bone-patella tendon-bone (BTB) or hamstring tendon (HT) graft using three-dimensional (3-D) computer models. METHODS: Thirty-two patients who underwent ACL reconstruction and postoperative computed tomography (CT) at 3 weeks and 6 months were included in this study. Of these, 20 patients underwent ACL reconstruction with a BTB graft (BTBR group), and the remaining 12 with an HT graft (HTR group). The area of the femoral tunnel aperture was extracted and measured using a 3-D computer model generated from CT images. Changes in the area and migration direction of the femoral tunnel aperture during this period were compared between the two groups. RESULTS: In the HTR group, the area of the femoral tunnel aperture was significantly increased at 6 months compared to 3 weeks postoperatively (P < 0.05). The average area of the femoral tunnel aperture at 6 months postoperatively was larger by 16.0 ± 12.4% in the BTBR group and 41.9 ± 22.2% in the HTR group, relative to that measured at 3 weeks postoperatively (P < 0.05). The femoral tunnel aperture migrated in the anteroinferior direction in the HTR group, and only in the inferior direction in the BTBR group. CONCLUSIONS: The femoral tunnel aperture in the HTR group was significantly more enlarged and more anteriorly located at 6 months after ACL reconstruction, compared to the BTBR group. LEVEL OF EVIDENCE: IV.