Shizuka Sasaki

Prospective Randomized Study of Objective and Subjective Clinical Results Between Double-Bundle and Single-Bundle Anterior Cruciate Ligament Reconstruction

Background: There is controversy as to whether double-bundle anterior cruciate ligament (ACL) reconstruction with hamstring tendon graft (DB-HT) or single-bundle ACL reconstruction with patellar tendon graft (SB-PT) obtains the best clinical outcomes. Purpose: To compare the short-term clinical outcomes of DB-HT with those of rectangular-tunnel SB-PT (RTSB-PT) at 2-year follow-up and to identify the factors that affect subjective knee functional score. Study Design: Randomized controlled trial. Level of evidence, 1. Methods: Sixty-three male patients (mean age, 26.1 years) and 87 female patients (mean age, 25.8 years) were included in this study and were randomly distributed to either the DB-HT (n = 76) or RTSB-PT (n = 74) group. Clinical outcomes (knee flexion range of motion [ROM], heel-height difference, side-to-side difference in anterior laxity, rotational laxity, and Tegner activity score) were compared between the DB-HT and RTSB-PT groups, and examination of factors affecting subjective outcomes (Knee Injury and Osteoarthritis and Outcome Score [KOOS] results) was performed by multiple linear regression analysis. Results: Fourteen patients (9 DB-HT, 5 RTSB-PT) had secondary ACL injury within 2 years after primary ACL reconstruction and were excluded from analysis. In the examination of 136 patients at the 24-month follow-up, there was no significant difference between the 2 groups in clinical or subjective outcomes. The normalized knee extensor strength of the RTSB-PT group showed negative surgical technique effect in the early postoperative phase (P = .005), but there was no significant difference between the 2 groups at the 24-month follow-up (P = .114). There was no significant difference in change of normalized knee flexor strength between the 2 groups (P = .493). Age, sex, body mass index (BMI), and presence of meniscus injury were the factors that affected KOOS subscale scores. Conclusion: In this prospective randomized controlled study, there was no significant difference in the incidence of secondary ACL injury and no difference in objective or subjective outcomes between the DB-HT and RTSB-PT reconstruction at 24-month follow-up. Age, sex, presence of meniscus injury, and BMI affected subjective KOOS subscale scores, while surgical technique did not.

Anthropometric and Skeletal Parameters Predict 2-Strand Semitendinosus Tendon Size in Double-Bundle Anterior Cruciate Ligament Reconstruction

Background: Few studies have examined whether skeletal parameters predict hamstring graft size during anterior cruciate ligament reconstruction (ACLR). Purpose/Hypothesis: The purpose of this study was to examine whether preoperative anthropometric and radiographic skeletal parameters could predict hamstring graft size during ACLR. We hypothesized that both anthropometric and skeletal parameters can be used to predict graft size in our double-bundle procedure and that the use of skeletal parameters will improve the accuracy of graft size prediction. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 200 patients were recruited and underwent double-bundle ACLR using a semitendinosus (ST) graft. The harvested tendon was measured to determine graft length (GL) and then split at its midpoint. The graft diameters of the anteromedial (GDAM) and posterolateral bundles (GDPL) were measured at the femoral aspect of the 2-stranded graft. The mean diameters of both bundles were included in the analysis. On the coronal radiograph, femorotibial angle (FTA), femoral interepicondylar distance (IED), and tibial plateau width (coronal tibial width [CTW]) were measured. Blumensaat line length (BLL) and the lateral tibial width (LTW) were measured on the lateral radiograph. A linear regression analysis was conducted using graft size as the dependent variable and age, sex, height, weight, Tegner activity score, and skeletal parameters as the independent variables. Results: Mean GL was 258.9 ± 21.9 mm, GDAM was 5.9 ± 0.5 mm, and GDPL was 5.7 ± 0.6 mm. Single regression analysis showed that GL was significantly predicted by sex, height, weight, Tegner activity score, IED, CTW, BLL, and LTW (R 2 range, 0.033-0.342). GD was predicted by sex, height, weight, IED, CTW, BLL, and LTW (R 2 range, 0.094-0.207). Stepwise multiple linear regression analysis significantly confirmed sex, height, and age as the variables to comprehensively predict GL (R 2 = 0.384). With regard to GD, stepwise multiple regression confirmed height and IED as significant variables (R 2 = 0.224). Conclusion: Both preoperative anthropometric and radiographic parameters on plain radiographs were able to predict harvested GL and 2-strand GD. Multivariate regression slightly improved the prediction of graft dimensions compared with univariate regression.

TRUNK MOTION AND MUSCULAR STRENGTH AFFECT KNEE VALGUS MOMENT DURING SINGLE-LEG LANDING AFTER OVERHEAD STROKE IN BADMINTON

Background Anterior cruciate ligament (ACL) injury in knees opposite to the racket-hand side frequent occurs during single-leg landing after overhead stroke in badminton. Although large lateral inclination of trunk during single-leg landing seems to generate knee valgus moment which causes ACL injury, it has not been examined. Objective To evaluate if there was a correlation between trunk kinematics and knee valgus moment during single-leg landing after overhead stroke, in addition, to evaluate an association with muscular strength of trunk. Design Controlled laboratory study. Setting Female college badminton players with no history of knee injury. Participants 8 right-handed players. Risk factor assessment Subjects performed single-left-legged landing after an overhead stroke following back-stepping. The kinematic and kinetic data of the trunk and left lower extremity during landing were measured using 3-dimensional motion analysis system. Isometric trunk flexion and extension strength was measured using a dynamometer. Main outcome measurement Change in lateral trunk bending angle and maximum knee valgus moment during landing were measured. The correlation between these and trunk strength were analyzed. Results The average of maximum knee valgus moment was 0.34±0.24 Nm/kg/m, and the change in lateral trunk bending angle was 22.9±13.3 degrees, respectively. The mean trunk flexion strength was 2.2±0.9 Nm/kg. The knee valgus moment was significantly correlated with the change in lateral trunk bending angle (r=0.87, P<.05) and the trunk flexion strength (r=−0.94, P<.01). The change in lateral trunk bending angle was also significantly correlated with the trunk flexion strength (r=−0.94, P<.01). Conclusions Larger lateral trunk bending associated with weak flexion strength increased knee valgus moment during single-leg landing. The core muscle training focused on trunk flexion strength may improve neuromuscular control of trunk and avoid excessive knee valgus moment in playing badminton, and this may play an important role of ACL injury prevention.

Quantitative analysis of dynamic patellar tracking in patients with lateral patellar instability using a simple video system

BACKGROUND As patellar dislocation occurs during activity, it is more important to assess the behavior of the patellofemoral joint under dynamic conditions. The aim of this study was to compare patellar tracking between knees with and without patellar dislocation in patients with an unstable patella and healthy controls using a simple video technique. METHODS Twenty-three knees with patellar dislocation (dislocated group), 23 contralateral knees without dislocation (non-dislocated group), and 23 healthy knees (control group) were examined. Those with skin markers on anatomical landmarks were made to extend their knees actively, and skin markers were attached to the examiners fingertips and the patella was followed by pinching. The knee during active knee extension was recorded with digital video cameras. The patella was tracked on imaging software, and the mediolateral patellar position (% patellar position: %PP) was calculated in reference to the knee width consecutively. RESULTS %PP was significantly different between the dislocated and control groups, from 30° (mean±SD: 58.9±6.2%, 54.6±4.7%) to 5° (64.2±5.2%, 55.2±5.2%). It was also significantly different between the non-dislocated and control groups, from 25° (58.9±7.1%, 54.5±4.6%) to 5° (63.8±6.5%, 55.2±5.2%). No significant difference in %PP was found between the dislocated and non-dislocated groups. CONCLUSION With the new video system, patellar tracking during active knee extension was successfully quantified. The tracking patterns were the same in knees with and without patellar dislocation, and the tracking in patients significantly differed from that in the controls at lower knee flexion angles. CLINICAL RELEVANCE The development of a quantitative examination technique for dynamic patellar tracking, which is easy to use and repeatedly applicable in a clinical situation, could help to follow-up the time-dependent changes and analyze the treatment effect on an unstable patella.

Age-related reduction of trunk muscle torque and prevalence of trunk sarcopenia in community-dwelling elderly: Validity of a portable trunk muscle torque measurement instrument and its application to a large sample cohort study

Trunk muscle weakness and imbalance are risk factors for postural instability, low back pain, and poor postoperative outcomes. The association between trunk muscle strength and aging is poorly understood, and establishing normal reference values is difficult. We aimed to establish the validity of a novel portable trunk muscle torque measurement instrument (PTMI). We then estimated reference data for healthy young adults and elucidated age-related weakness in trunk muscle strength. Twenty-four university students were enrolled to validate values for PTMI, and 816 volunteers from the general population who were recruited to the Iwaki Health Promotion Project were included to estimate reference data for trunk muscle strength. Trunk flexion and extension torque were measured with PTMI and KinCom, and interclass correlation coefficients (ICC) were estimated to evaluate the reliability of PTMI values. Furthermore, from the young adult reference, the age-related reduction in trunk muscle torque and the prevalence of sarcopenia among age-sex groups were estimated. The ICC in flexion and extension torque were 0.807 (p<0.001) and 0.789 (p<0.001), respectively. The prevalence of sarcopenia increased with age, and the prevalence due to flexion torque was double that of extension torque. Flexion torque decreased significantly after 60 years of age, and extension torque decreased after 70 years of age. In males over age 80, trunk muscle torque decreased to 49.1% in flexion and 63.5% in extension. In females over age 80, trunk muscle torque decreased to 60.7% in flexion and 68.4% in extension. The validity of PTMI was confirmed by correlation with KinCom. PTMI produced reference data for healthy young adults, and demonstrated age-related reduction in trunk muscle torque. Trunk sarcopenia progressed with aging, and the loss of flexion torque began earlier than extension torque. At age 80, trunk muscle torque had decreased 60% compared with healthy young adults.

Axillary artery and brachial plexus injury secondary to proximal humeral fractures: A report of 2 cases

Highlights • Axillary artery and brachial plexus injury secondary to proximal humeral fracture is rare but can lead to be severe sequels.• The anatomical position of the axillary artery makes it susceptible to injury secondary to proximal humeral fracture.• The upper limbs are rich in collateral circulation and vascular damage cannot be ruled out even if the radial pulse is palpable.• The most common vascular injury secondary to proximal humeral fracture was an intimal tear with secondary thrombosis.• The dislocated humeral head fracture suggested that the nerve injury in both patients was primarily caused by a mechanical factor.

MECHANISMS OF ANTERIOR CRUCIATE LIGAMENT INJURIES IN VOLLEYBALL

Background Knee injuries were common in volleyball players, and ACL injury is a serious injury for athletes. Objective The purpose of this study was to investigate the mechanism of ACL injury in volleyball players using a questionnaire. Design Research study using a questionnaire. Setting Volleyball players who had ACL reconstruction at our institution. Patients Twenty-five females and 1 male (mean age; 24.6±11.0 years-old) volleyball players who ruptured their ACL during volleyball and underwent ACL reconstruction. Assessment of Risk Factors They were asked about their position, dominant hand defined as the spiking hand, side of injury, event during which the injury occurred (game or practice), the circumstance of injury (the situation in which the injury occurred, the specific motion at the time of injury) and player position and court location where the injury occurred. Results There were 19 wing spikers (left 13, right 6). Twenty-four players were right-handed and 2 players were left-handed, and 23 players injured the knees opposite to dominant hand. The 65.4% of injuries were prevalent during game. Twenty players (76.9%) were injured during spiking. Twenty-one players (80.8%) receive injured during landing, and 16 of them injured with single-leg landing after spiking. Most of ACL injuries (84.6%) occurred in front of the attack line near the net. Conclusions Single leg landing after spiking close to the net was the most common cause of injury, and most of wing spikers injured the knee opposite to their dominant hand. It suggests that wing spikers need to consider prevention strategies focusing on spiking movement.