Risk factors of failure results after double-bundle reconstruction with autogenous hamstring grafts for isolated posterior cruciate ligament rupture cases.

Posterior tibial translation (PTT) after double-bundle posterior cruciate ligament (PCL) reconstruction has sometimes occurred. Purpose of this study is to identify the risk factors for postoperative PTT after double-bundle PCL reconstruction with a hamstring autograft. Comparing the results of bilateral gravity sag view (GSV) at 12 months after surgery, over 5-mm PTT was defined as 'failure' in this study. Of 26 isolated PCL reconstruction cases, over 5-mm PTT was seen in 7 cases (group F: 9.57 ± 1.28 mm), and 19 cases had less than 5 mm (group G: 2.84 ± 1.29 mm). Age, sex, body mass index (BMI), preoperative GSV, posterior slope angle of the tibia, anterolateral bundle (ALB) and posteromedial bundle (PMB) graft diameters, and tibial tunnel diameter were evaluated. The two groups were compared with the 2 × 2 chi-squared test, the Mann Whitney U-test, and Spearman's rank correlation coefficient. Multivariate logistic regression analysis was also performed to determine the risk factor. Statistical significance was indicated as p < 0.01 for correlation with postoperative PTT, and as p < 0.05 for all other comparisons. Mean age (group G 31.8 ± 12.5 vs group F 34.9 ± 15.9 years), sex (male/female: 15/4 vs 3/4), BMI (25.6 ± 4.6 vs 24.9 ± 3.9 kg/m2), preoperative GSV (11.3 ± 2.2 vs 11.6 ± 2.9 mm), PMB diameter (5.37 ± 0.33 vs 5.36 ± 0.48 mm), and tibial tunnel diameter (9.32 ± 0.58 vs 9.29 ± 0.49 mm) showed no significant differences. ALB diameter was significantly greater in group G (7.0 ± 0.5 mm) than in group F (6.5 ± 0.29 mm; p = 0.022). There was also a significant difference in posterior tibial slope angle (group G 9.19 ± 1.94 vs group F 6.54 ± 1.45, p = 0.004). On Spearman rank correlation coefficient analysis, ALB diameter GSV (correlation coefficient: - 0.561, p = 0.003) and posterior tibial slope angle (correlation coefficient: - 0.533, p = 0.005) showed a significant correlation with postoperative PTT. Multivariate logistic regression analysis showed that ALB diameter (OR 19.028; 95% CI 1.082-334.6; p = 0.044) and posterior slope angle of tibia (OR 3.081; 95% CI 1.109-8.556; p = 0.031) were independently associated with postoperative PTT, respectively. In double-bundle PCL reconstruction with hamstring, smaller ALB graft diameter and lower (flatted) tibial slope angle were considered risk factors for postoperative PTT.

Risk factors associated with throwing injuries in young baseball players.

BACKGROUND: Few studies have retrospectively analyzed the relationship between joint range of motion (ROM) and muscle flexibility and shoulder and elbow throwing injuries in a large number of elementary school baseball players. The purpose of this study was to retrospectively identify the physical factors related to shoulder and elbow throwing injuries in younger baseball players. METHODS: A total of 2466 younger baseball players belonging to our Prefecture Rubber Baseball Federation who participated in medical check-ups from 2016 to 2019 were analyzed. Players completed a questionnaire and had a medical check-up that included a physical examination and ultrasonography. ROM (internal rotation [IR] angle and external rotation angle) of the shoulder and hip and the finger-to-floor distance and heel-to-buttock distance were measured. The straight leg raise was also performed. The results of two groups (normal group and injury group) were compared using the χ2 test, Mann-Whitney U test, and Student t test. Stepwise forward logistic regression models were developed to identify risk factors. RESULTS: On univariate analysis, nine of the 13 evaluated items showed significant decreases in ROM and muscle flexibility in the injury group. On multiple logistic regression analysis, grade, finger-to-floor distance, IR angle of the dominant side shoulder, and IR angle of the nondominant side hip were significantly associated with the occurrence of throwing injuries. Decreased total shoulder angle was observed not only on the dominant side but also on the nondominant side in the injury group. CONCLUSION: Decreased ROM and muscle flexibility were risk factors for baseball-related throwing injuries in elementary school baseball players. To prevent shoulder and elbow throwing injuries, players, coaches, medical staff, and parents need to be aware of these findings.

Remnant-Preserved Single-Bundle Anterior Cruciate Ligament Augmentation in Multi-ligamentous Knee Reconstruction.

This study was conducted to present remnant-preserving anterior cruciate ligament (ACL) augmentation as a useful option for partial ACL injury in multiligament knee injury (MLKI) cases, which may also contribute to conserving graft resources. The present study involved patients diagnosed with MLKI at our institute from Spring 2006 to February 2021. A total of 71 MLKI cases were provided surgery due to knee instability and disability. For every patient, an arthroscopic diagnostic was performed to ensure that ACL tear and a remnant were present. When the ACL remnant was classified into group 2, 3, or 4 of Nakamae's classification, remnant-preserved single bundle ACL augmentation was performed. Graft selection and the combination of injured ligaments were evaluated. The side-to-side difference under an anterior tibial load of 134 N with an arthrometer and the leg symmetry index at 60 degrees/s were measured. The present procedure was performed for five cases (male/female: 4/1, mean age: 33.6 years). The mean follow-up period was 26.4 months. The combination of torn ligaments was as follows: 3 cases of ACL + medial collateral ligament, one case of ACL + posterior cruciate ligament, and one case of ACL + posterolateral corner. An ACL augmentation graft was performed using an ipsilateral gracilis tendon in 2 cases, a contralateral full semitendinosus tendon in 2 cases, and the ipsilateral distal 1/2 of the semitendinosus tendon in 1 case. The mean side-to-side difference was 1.07 ± 0.4 mm. The mean leg symmetry index was 82.6 ± 12.2% in knee extension and 96.3 ± 9.9% in knee flexion. Although the present study was a small case series, the remnant-preserved single-bundle ACL augmentation for MLKI surgery provided good clinical outcome and conserved the graft resource. Even in the MLKI case, this technique is one of the useful surgical options. The level of evidence of this study is level IV (case series).

Internal Fixation of a Lateral Inverted Osteochondral Fracture of the Talus (LIFT) Lesion Using an Innovative Surgical Approach: Inverting the Capsulo-Lateral Fibulotalocalcaneal Ligament (LFTCL)-Fibular Periosteum Complex.

Osteotomy of the distal fibula or anterolateral corner of the tibia is usually required to fix a displaced osteochondral fracture of the talus that is located central to posterior area of the lateral talar dome. However, osteotomy is an invasive procedure and is associated with complications, including nonunion, persistent pain, and hardware-related problems. Lateral inverted osteochondral fracture of the talus (LIFT) lesion is an extremely rare type of displaced osteochondral lesion of the talus. We describe a case in which a LIFT lesion was fixed using an innovative surgical approach, inverting capsulo-lateral fibulotalocalcaneal ligament (LFTCL)-fibular periosteum complex, with a favorable short-term clinical outcome.

Orthopaedic medical examination for young amateur athletes: a repeated cross-sectional study from 2014 to 2018.

OBJECTIVES: Medical examinations for adult elite athletes are performed all over the world, however, no studies in the relevant English literature have reported on orthopaedic medical examinations for young amateur athletes. The purpose of this study was to report the results of orthopaedic medical examinations of the spine and lower extremities in young amateur athletes. METHODS: This repeated cross-sectional study from 2014 to 2018 included a total of 323 young amateur athletes (age, 12-18 years) who were active in one of the following four sports: boxing, canoeing, weightlifting and track and field. The orthopaedic medical examination consisted of six assessments (physical examinations, the generalised joint laxity, muscle and joint tightness, static alignment and muscle volume of the lower extremities and the medial longitudinal arch of the foot). Questions regarding pain in the spine and lower extremities were also performed. RESULTS: Among 323 young amateur athletes, 17 (5.3%) had received orthopaedic treatment at the time of the medical examination, with spondylolysis being the most common cause (29.4%, 5/17). Among 306 young athletes who had not received orthopaedic treatment, 61 (19.9%) had at least one positive finding in physical examinations or had pain in the spine or lower extremities. Anterior drawer test of the ankle and Kemp test for the spine accounted for 34% and 28% of positive findings, respectively. Low back pain and knee pain accounted for 58% and 16% of pain, respectively. CONCLUSIONS: The present study showed that approximately one-fifth of young amateur athletes who had not received orthopaedic treatment had pain in the spine and lower extremities and positive findings in physical examinations that may require orthopaedic treatments. In addition to the early detection of injuries, orthopaedic medical examinations for young amateur athletes provide an opportunity to educate such athletes.

Clinical and Radiographic Outcomes of Double-Bundle Anterior Cruciate Ligament Reconstruction for Asian Patients with Bone-Patellar Tendon-Bone and Gracilis Tendon Grafts: A Matched-Control Comparison.

For anterior cruciate ligament (ACL)-deficient patients, using a single bone-patellar tendon-bone (BPTB) graft for the double-bundle concept is one of the suitable approaches for acquiring better stability and reducing bone tunnel enlargement compared with the use of hamstring grafts. At least 10-mm width of BPTB autograft is needed to achieve this concept; however, it is larger than one-third of the patellar tendon width for small or middle physique patients. This study aimed to assess the clinical and radiographic outcomes of BPTB and gracilis (G) composite autografts for primary double-bundle ACL reconstruction in Asian athletes. Thirty-two Asian patients undergoing double-bundle ACL reconstruction with 7.0 to 7.5 mm of BPTB and 5.0 to 5.5 mm of G composite grafts were compared with 43 double-bundle ACL reconstruction with hamstring graft cases. The BPTB graft was used for the anteromedial bundle (AMB), with the G graft for the posterolateral bundle (PLB). Percentage of femoral bone tunnel enlargement compared with the original size was determined by computed digital radiographs on the first postoperative day and at 12 months in the anteroposterior (AP) and lateral views. Standard clinical evaluations, including the limb symmetry index (LSI), were also performed. Less PLB tunnel enlargement was found in the BPTB + G group than in the hamstring group in the AP (101.9 ± 22.9 vs.113.7 ± 20.6%, p = 0.031) and lateral views (104.4 ± 18.1 vs. 120.6 ± 23.4%, p < 0.01).There was no significant difference between the groups in 12-month postoperative clinical outcomes (Lysholm's score, Tegner's activity level scale, and International Knee Documentation Committee subjective knee evaluation score).The side-to-side difference was significantly less in the BPTB + G group (0.2 ± 1.3 vs. 0.9 ± 1.1 mm, p = 0.026). Despite the small sizes of the BPTB and G grafts, there was no significant difference in the knee extensor LSI between the groups (92.9 ± 10.1 vs. 93.3 ± 12.2%, p = 0.707), whereas the knee flexor LSI was significantly higher in the BPTB + G group (97.7 ± 14.8 vs. 90.1 ± 13.3%, p = 0.033). Double-bundle ACL reconstruction with a small size BPTB and G composite graft procedure provided good clinical outcomes and significantly less femoral bone tunnel enlargement than the hamstring procedure 12 months after surgery. It is thus a useful surgical option for ACL-deficient Asian athletes. This study reflects level of evidence III.

Binding mode of novel 1-substituted quinazoline derivatives to poly(ADP-ribose) polymerase-catalytic domain, revealed by X-ray crystal structure analysis of complexes.

In order to clarify the role of the 1-substituent of quinazoline derivatives in their inhibitory activity against poly(ADP-ribose) polymerase (PARP), two novel inhibitors, 1 [8-hydroxy-1-(3-morpholinopropyl)-quinazoline-2,4(1H,3H)-dione] and 2 [8-hydroxy-1-(3-phenoxypropyl)-quinazoline-2,4(1H,3H)-dione], were synthesized and subjected to X-ray crystal analysis in complex with the PARP C-terminal catalytic domain (PARP-CD), which requires NAD+ coenzyme for biological function. The nicotinamide-mimicking part of the quinazoline skeleton of 1 and 2 were both located at the nicotinamide subsite of the NAD+-binding pocket in the same manner as previously reported inhibitors: three hydrogen bonds [(Gly-863)NH-O12, (Gly-863)O-HN3 and (Ser-904)O(gamma)-O12] and stacking interaction between the Tyr-907 phenol and the quinazoline ring. On the other hand, the N-morpholinoprop-3-yl moiety introduced at the 1-position of the quinazoline ring in 1 bridged the large gap between the donor site and the acceptor site through a (Met-890)NH-O20(morpholine) hydrogen bond, where the donor and the acceptor sites are classified as the binding sites of NAD+ and the ADP moiety of the poly(ADP-ribose) chain, respectively. In contrast, the N-phenoxyprop-3-yl moiety in 2 formed hydrophobic interactions close to the adenosine-binding site of NAD+, unlike the hydrogen bond such as in 1. As the inhibitory activities of 1 and 2 for PARP were much more potent than those of the unsubstituted nicotinamide analogues, these results suggest that the occupation of the proximal region of the ADP phosphate-and adenosine-binding subsite of the donor site or that of the gap between the donor and the acceptor site by the 1-substituent of quinazoline may increase the inhibitory activity considerably. The nearly equal inhibitory activities of 1 and 2, despite of their different binding modes at the active site, indicate that this 1-substituent is promising in improving the bioavailability of the inhibitor without compromising its inhibitory activity.