Muscle activation patterns in acceleration-based phases during reach-to-grasp movement.

[Purpose] An earlier study divided reaching activity into characteristic phases based on hand velocity profiles. By synchronizing muscle activities and the acceleration profile, a phasing approach for reaching movement, based on hand acceleration profiles, was attempted in order to elucidate the roles of individual muscle activities in the different phases of the acceleration profile in reaching movements. [Subjects and Methods] Ten healthy volunteer subjects participated in this study. The aim was to electromyographically evaluate muscles around the shoulder, the upper trapezius, the anterior deltoid, the biceps brachii, and the triceps brachii, most of which have been used to evaluate arm motion, as well as the acceleration of the upper limb during simple reaching movement in the reach-to-grasp task. [Results] Analysis showed the kinematic trajectories of the acceleration during a simple biphasic profile of the reaching movement could be divided into four phases: increasing acceleration (IA), decreasing acceleration (DA), increasing deceleration (ID), and decreasing deceleration (DD). Muscles around the shoulder showed different activity patterns, which were closely associated with these acceleration phases. [Conclusion] These results suggest the important role of the four phases, derived from the acceleration trajectory, in the elucidation of the muscular mechanisms which regulate and coordinate the muscles around the shoulder in reaching movements.

Trunk kinematics and muscle activities during arm elevation.

BACKGROUND: While trunk movement accompanies arm elevation, trunk muscle activities during arm elevation at different speeds are unclear. The purpose of this study was to examine the trunk muscle activities at various speeds of arm elevation and then to evaluate their roles in trunk kinematics. METHODS: Twenty-two healthy subjects participated. The participants performed right shoulder flexion at three different speeds. Surface electromyography was used to measure the activities of bilateral external oblique muscles (EO), internal oblique muscles (IO), rectus abdominis muscles (RA) and lumber erector spinae muscles (ES). A three-dimensional motion analyzer was used to measure arm and trunk movements. RESULTS: In natural and slow movements, the muscle activities of left ES, right EO and left IO were significantly augmented compared with those of the contralateral muscles, in the relatively late phase. In fast movement, the muscle activities of both ES were significantly augmented during the early phase compared with later in the action. The muscle activities of the left ES and the right EO were significantly augmented compared with those of the contralateral muscles. There was a consistent pattern of trunk extension, lateral flexion and rotation during arm elevation, irrespective of the speed. CONCLUSIONS: Bilateral ES activity may be required for back-extension torques, especially for the early phase of rapid elevating motion. The anterior muscles' activity may contribute to the production of anterior force against the backward movement of the center of mass of the upper limb in the late phase. Trunk rotation, controlled by the trunk muscles in harmony, may assist the scapular movement to align the scapular plane in the arm elevating plane.

Relationship between joint motion and acceleration during single-leg standing in healthy male adults.

[Purpose] The purpose of this study was to clarify the relationship between acceleration and joint movement by synchronizing accelerometers and a three-dimensional motion analysis system, and to show the utility of an accelerometer as a postural control assessment tool. [Subjects and Methods] Head, lumbar, shank accelerations and various joint angles during single-leg standing were measured of 20 healthy males. Root mean squares of acceleration and joint angle were calculated. Fast Fourier transform analysis was performed for head, lumbar, and shank accelerations, and the median frequencies were calculated. Then, principal component analysis was performed for the median frequency of each acceleration. Stepwise multiple regression analysis was also used to examine the relationship between joint angle and acceleration. [Results] The score of the first principal component was highest for shank acceleration, while that of the second principal component was highest for lumbar and head accelerations. In multiple regression analysis, hip flexion/extension and adduction/abduction were identified as variables associated with head acceleration. [Conclusion] We were able to confirm the aggregation of acceleration into two components, which we interpreted as postural control strategies using primarily the ankle and hip joints. Furthermore, though multiple regression analysis, we were able to clarify the joint movement indicated by acceleration of each segment.

Toe-out angle changes after total knee arthroplasty in patients with varus knee osteoarthritis.

PURPOSE: Toeing-out is a commonly proposed kinematic variable that has been suggested to reduce external knee adduction moment. Analyses of the toe-out angle after total knee arthroplasty (TKA) are useful for obtaining a proper understanding of the abnormal gait caused by varus knee osteoarthritis (OA), as well as performing rehabilitation after arthroplasty. Changes in the toe-out angle after arthroplasty have not yet been defined or analysed. METHODS: The study population consisted of 32 knees in 32 patients with varus knee OA who underwent TKA. The femorotibial angle was evaluated on standing anteroposterior radiographs before and after arthroplasty. The subjects underwent three-dimensional motion capture analyses to measure gait parameters (walking speed, cadence, stride length, step length, step width and the relative length of the single-limb support (SLS) percentage of one gait cycle) and the maximal hip adduction angle in the stance phase, the trunk lean angle in the coronal plane and the toe-out angle before and 4 weeks after arthroplasty. RESULTS: The femorotibial angle on the side of arthroplasty improved after surgery. Among the measured gait parameters, only the SLS percentage increased significantly. The hip adduction angle and toe-out angle on the side of arthroplasty increased significantly after surgery. CONCLUSIONS: The knee alignment and hip adduction angle in the coronal plane and SLS phase were normalized after arthroplasty. The increase in the toe-out angle after arthroplasty may be attributable to the restoration of a normal knee alignment. These findings contribute to obtaining a proper understanding of the abnormal gait caused by varus knee OA and are useful for orthopaedic surgeons and rehabilitation therapists when treating patients after arthroplasty. LEVEL OF EVIDENCE: Prospective study, Level II.

Graft impingement in anterior cruciate ligament reconstruction.

Anterior cruciate ligament (ACL) graft impingement is one of the most troubling complications in ACL reconstruction. In the previous strategy of isometric "non-anatomical" ACL reconstruction, posterior tibial tunnel placement and notchplasty were recommended to avoid graft impingement. Recently, the strategy of ACL reconstruction is shifting towards "anatomical" reconstruction. In anatomical ACL reconstruction, the potential risk of graft impingement is higher than in non-anatomical reconstruction because the tibial tunnel is placed at a more anterior portion on the tibia. However, there have been few studies reporting on graft impingement in anatomical ACL reconstruction. This study will provide a review of graft impingement status in both non-anatomical and the more recent anatomical ACL reconstruction techniques. In conclusion, with the accurate creation of bone tunnels within ACL native footprint, the graft impingement might not happen in anatomical ACL reconstruction. For the clinical relevance, to prevent graft impingement, surgeons should pay attention of creating correct anatomical tunnels when they perform ACL reconstruction. Level of evidence IV.

Patient selection of anatomical double bundle or traditional single bundle ACL reconstruction.

PURPOSE: This study was designed as a questionnaire survey to reveal the preference in technique of patients faced with anterior cruciate ligament (ACL) reconstruction. METHODS: One hundred and ten subjects (35 patients and 75 medical students) were included in this study. A questionnaire survey was conducted, and the following questions were asked: (1) How old are you? (2) Prior to this survey, did you know what the ACL was? (3) Prior to this survey, did you have any knowledge about ACL reconstruction technique? (4) Prior to this survey, did you know the difference between anatomical double bundle (DB) technique and traditional single bundle (SB) technique? (5) If you had to have an ACL reconstruction, which technique would you prefer? In the same questionnaire, between questions (3) and (4), a description of SB and DB was provided. RESULTS: Sixty-nine percent of patients and 100% of medical students knew what the ACL was. Forty-three percent of patients and 85% of medical students had previous knowledge about ACL reconstruction. None of the patients and only 29% of the medical students had prior knowledge about the difference between DB and SB. Six percent of patients selected SB, and 40% selected DB. Nine percent of medical students selected SB, and 67% selected DB. CONCLUSION: In this study, 46% of patients and 76% of medical students selected one of the operation techniques. The trend in selection of the operation technique was significantly influenced by the subjects' prior medical knowledge. It might be possible to apply the principle of "informed patient choice" to the selection of DB or SB for ACL reconstruction. LEVEL OF EVIDENCE: Decision analysis, Level III.

Size comparison of ACL footprint and reconstructed auto graft.

PURPOSE: The purpose of this study was to compare the size of native anterior cruciate ligament (ACL) footprints and the size of commonly used auto grafts. The hypothesis was that the reconstructed graft size with auto grafts might be smaller than the native ACL footprint. METHODS: Fourteen non-paired human cadaver knees were used. The semitendinosus tendon (ST) and the gracilis (G) tendon were harvested and prepared for ACL grafts. Simulating an ST graft, the ST was cut in half. The bigger half was regarded as the antero-medial (AM) bundle, and the remaining half was regarded as the postero-lateral (PL) bundle. Simulating an ST-G graft, the bigger half of the ST and G were regarded as the AM bundle, and the smaller half of the ST was regarded as the PL bundle. Each graft diameter was measured, and the graft area was calculated. Simulating a rectangular bone-patella tendon-bone (BPTB) graft, a 10-mm wide BPTB graft was harvested and the area calculated. The ACL was carefully dissected, and the size of the femoral and tibial footprints was measured using Image J software (National Institution of Health). RESULTS: The average areas of the ST, ST-G, and BPTB graft were 52.3 ± 7.3, 64.4 ± 9.2, and 32.7 ± 6.5 mm(2), respectively. The sizes of the native femoral and tibial ACL footprints were 85.4 ± 26.3 and 145.4 ± 39.8 mm(2), respectively. Only the ST-G graft showed no significant difference in graft size when compared with the femoral ACL footprint. CONCLUSION: Only the ST-G auto graft was able to reproduce the native size of the ACL footprint on the femoral side. None of the auto grafts could reproduce the size of the tibial ACL footprint. For clinical relevance, ST-G graft is recommended in order to reproduce the native size of the ACL in anatomical ACL reconstruction with auto graft.

ACL footprint size is correlated with the height and area of the lateral wall of femoral intercondylar notch.

PURPOSE: The purpose of this study was to reveal the correlation between the size of the native anterior cruciate ligament (ACL) footprint and the size of the lateral wall of femoral intercondylar notch. METHODS: Eighteen non-paired human cadaver knees were used. All soft tissues around the knee were resected except the ACL. The ACL was cut in the middle, and the femoral bone was cut at the most proximal point of the femoral notch. The ACL was carefully dissected, and the periphery of the ACL insertion site was outlined on both the femoral and tibial sides. An accurate lateral view of the femoral condyle and the tibial plateau was photographed with a digital camera, and the images were downloaded to a personal computer. The size of the femoral and tibial ACL footprints, length of Blumensaat's line, and the height and area of the lateral wall of femoral intercondylar notch were measured with Image J software (National Institution of Health). RESULTS: The sizes of the native femoral and tibial ACL footprints were 84 ± 25.3 and 144.7 ± 35.9 mm(2), respectively. The length of Blumensaat's line and the height and area of the lateral wall of femoral intercondylar notch were 29.4 ± 2.8 mm, 17.1 ± 2.7 mm, and 392.4 ± 86 mm(2), respectively. Both the height and the area of the lateral wall of femoral intercondylar notch were significantly correlated with the size of the ACL footprint on both the femoral and tibial sides. CONCLUSION: For clinical relevance, the height and area of the lateral wall of femoral intercondylar notch can be a predictor of native ACL size prior to surgery. However, the length of Blumensaat's line showed no significant correlation with native ACL size.

Evaluation of the prevalence, lesion, and depth of osteoarthritic changes in the patella.

PURPOSE: The aim of this study was to determine the prevalence, type of lesion, and depth of osteoarthritic (OA) changes in the patella. METHODS: One hundred and forty-six cadaveric knees were included in this study with an median age of 83 years (54-97). Patella OA lesion was classified using Han's method: Type 1, no or minimal lesion; Type 2, medial facet lesion without involvement of the ridge; Type 3, lateral facet lesion without involvement of the ridge; Type 4, lesion involvement of the ridge; Type 5, medial facet lesion with involvement of the ridge, Type 6, lateral facet lesion with involvement of the ridge; and Type 7, Global lesion. The depth of OA evaluation was performed following Outerbridge's classification. RESULTS: OA lesions were observed as follows: (Type 1) 31%, (Type 2) 16%, (Type 3) 3%, (Type 4) 12%, (Type 5) 22%, (Type 6) 2%, and (Type 7) 14%. Outerbridge's classification of over Grade 2 OA depth was observed in 63.7% of subjects. A significant difference of patella OA type in gender was observed. Severe patella OA occurred in female subjects. Greater depth of OA was observed in Types 5 and 7. Most OA occurred in the medial facet of the patella including the ridge. Isolated OA in the lateral facet of the patella was observed in only 2% of all knees. CONCLUSION: There is a risk of patella OA in female subjects. Patella OA occurred mainly on the medial side. Isolated OA in the lateral facet of the patella was rare. 63.7% of subjects had patella OA. LEVEL OF EVIDENCE: Controlled laboratory study, Level III.

Rollback of the femoral condyle in anatomical double-bundle anterior cruciate ligament reconstruction.

PURPOSE: The purpose of this study was to evaluate rollback of the femoral condyle in anatomical double-bundle anterior cruciate ligament reconstruction (ACL). METHODS: Twenty-two subjects who underwent anatomical double-bundle ACL reconstruction were included in this study. More than 6 months after surgery, lateral radiographic imaging of the knee was performed with active full knee flexion. The most posterior tibiofemoral contact point was measured for evaluation of femoral rollback (rollback ratio). Flexion angle was also measured using the same radiograph, and the correlation between rollback and flexion angle was analyzed. As a control, radiographs of the healthy contralateral knees were evaluated. For clinical evaluation, side-to-side difference in anterior tibial translation (ATT) and pivot shift test were analyzed approximately 1 year after surgery. RESULTS: The rollback ratios of the operated knees and the healthy contralateral knees were 28.7 ± 6.6 and 29.7 ± 6.7%, respectively, from the posterior edge of the tibia. No significant difference in rollback was observed. The flexion angles of the operated knees and the healthy contralateral knees were 136 ± 11° and 140 ± 9°, respectively. No significant difference in knee flexion angle was observed. Significant correlation between femoral rollback and knee flexion angle was observed. The side-to-side difference in ATT was 0.7 mm, and no cases of positive pivot shift were observed. CONCLUSION: Anatomical double-bundle ACL reconstruction can restore normal femoral rollback in active full knee flexion. For clinical relevance, knees with anatomical double-bundle ACL reconstruction can flex with normal kinematics at the end of knee flexion angle. LEVEL OF EVIDENCE: III.

Age as a predictor of residual muscle weakness after anterior cruciate ligament reconstruction.

PURPOSE: The objective of this study was to reveal the predicting factors for muscle recovery in the lower extremity after anterior cruciate ligament (ACL) reconstruction. METHODS: One hundred and thirty-five (135) patients who underwent ACL reconstruction using hamstring autograft were evaluated. Exclusion criteria were bilateral ACL injury, chondral treatment and multiple ligament injury. Nonanatomical single-bundle reconstruction (SB) was performed in 79 patients, and anatomical double-bundle reconstruction (DB) was performed in 56 patients. Strength of quadriceps and knee flexion muscles were assessed at 60°/s using a Cybex II dynamometer (Lumex, Ronkonkoma, NY) at 3, 6 and 9 months after ACL reconstruction. Anterior tibial translation and pivot shift test were also evaluated. The medical records were reviewed to extract the following information: age, gender, the amount of pre and postoperative KT 1000, technique of reconstruction (SB or DB) and postoperative knee rotation. RESULTS: No significant difference of muscle recovery in the lower extremity was observed at any time point after ACL reconstruction between the SB and DB groups. The DB group showed significantly better postoperative antero-posterior and rotational knee laxity than the SB group. Logistic regression analysis showed significant correlation with only age and muscle recovery. CONCLUSION: For clinical relevance, there is a risk of muscle recovery delay when ACL reconstruction is performed in elderly patients. Anatomical DB reconstruction resulted in significantly better knee stability, but had no positive effect on muscle recovery. LEVEL OF EVIDENCE: Retrospective study, Level II.

PCL to graft impingement pressure after anatomical or non-anatomical single-bundle ACL reconstruction.

BACKGROUND: Anterior cruciate ligament (ACL) graft impingement against the posterior cruciate ligament (PCL) has been postulated, but not thoroughly investigated. PURPOSE: To evaluate PCL impingement pressure and biomechanical stability with different tibial and femoral tunnel positions in ACL reconstruction. METHODS: In 15 porcine knees, the impingement pressure between ACL and PCL was measured using pressure sensitive film before and after ACL single-bundle reconstruction. ACL reconstructions were performed in each knee with three different tibial and femoral tunnel position combinations: (1) tibial antero-medial (AM) tunnel to femoral AM tunnel (AM-AM), (2) tibial postero-lateral (PL) tunnel to femoral High-AM tunnel (PL-High-AM) and (3) tibial AM tunnel to femoral High-AM tunnel (AM-High-AM). Anterior tibial translation (ATT) was evaluated after each ACL reconstruction using robotic/universal force-moment sensor testing system. RESULTS: There was no significant difference of the impingement pressure between AM and AM, PL-High-AM reconstructed groups and intact ACL. Only AM-High-AM ACL reconstruction group showed significantly higher impingement pressure compared with intact ACL. With regard to ATT, AM-AM group had significantly higher stiffness than PL-High-AM group. CONCLUSION: Anatomical ACL reconstruction does not cause PCL impingement and it has biomechanical advantage in ATT when compared with non-anatomical ACL reconstructions in porcine knee. For the clinical relevance, in the anatomical ACL reconstruction, no ACL-PCL impingement is found.

Anatomical evaluation of the rectus femoris tendon and its related structures.

PURPOSE: The purpose of this study was to evaluate the anatomical structure of the quadriceps tendon in detail for use as an anterior cruciate ligament (ACL) graft tendon. MATERIALS AND METHODS: Sixteen cadaveric knees with an average age of 78.8 were used. After careful dissection of skin and fascia, the muscle structure of each quadriceps was evaluated. In particular, the rectus femoris (RF) tendon was measured at its widest and narrowest width, the distance between widest or narrowest point and the proximal end of the patella, and the length. RESULTS: The quadriceps tendon consisted of three layers. At the surface layer, the RF tendon existed mostly independently. The middle layer consisted of the vastus lateralis (VL) and medialis (VM) tendons. The deep layer consisted of the vastus intermedius (VI) tendon. The VL and VI tendons overlapped and were firmly connected, constituting the strength and size of the quadriceps. The narrowest width of the RF was 15.3 mm, and the narrowest point existed 4.8 mm proximal to the upper end of the patella. The average length of the RF was 27.3 cm. CONCLUSION: If the RF tendon only is used as an ACL graft, surgeons should be cautious of the fact that the narrowest point of the RF tendon is located close to the patella. The entire quadriceps tendon is big enough to be used as an ACL graft. However, since the direction of the VL and VI tendons is different, the suitability of the quadriceps tendon as an ACL graft is questionable.

Full knee extension magnetic resonance imaging for the evaluation of intercondylar roof impingement after anatomical double-bundle anterior cruciate ligament reconstruction.

PURPOSE: The purpose of this study was to reveal the relationship between anatomically placed anterior cruciate ligament (ACL) graft and the intercondylar roof using magnetic resonance imaging (MRI). METHODS: Twenty patients undergoing anatomical double-bundle ACL reconstruction were included in this study. Anatomical double-bundle ACL reconstruction was performed with two femoral tunnels (antero-medial; AM and postero-lateral; PL) and two tibial tunnels. Hamstring autograft was used in all cases. More than 6 months after operation, MRI was performed with full knee extension. The relationship between the graft and the intercondylar roof was evaluated using an axial view of the T2 image at the most distal slice of the intercondylar roof. Qualitative evaluation of the ACL graft was performed with a sagittal view of the T2 image. Tunnel placement was evaluated with three-dimensional computed tomography (3D-CT) and radiographs. The extension angle of the knee was also evaluated with 3D-CT. RESULTS: In 12 subjects, the ACL graft touched the roof (Touch group) but no graft deformation was observed. In 8 subjects, no roof-graft contact was observed (Non-touch group). In 1 case, the ACL graft was bowed posteriorly. Signal intensity alteration of the graft was observed in 3 cases. No significant difference in femoral and tibial tunnel placement was observed between the Touch and Non-touch groups. All subjects attained full knee extension. CONCLUSION: Although graft-roof impingement after anatomical double-bundle ACL reconstruction was suspected in some cases after the MRI evaluation, no extension loss in the knee was observed. In these suspected cases of impingement, long-term follow-up will be needed to determine the connection between any potential pathological effects. For the clinical relevance, MRI is an effective tool to determine the status of roof impingement in anatomical double-bundle ACL reconstruction.

Alternation of trunk movement after arthroplasty in patients with osteoarthritis of the knee.

OBJECTIVE: Trunk movement is important but still little understood after total knee arthroplasty. The alternation of trunk movement was analyzed for use in a postoperative rehabilitation program in the short-term after arthroplasty. MATERIALS AND METHODS: The subjects were 25 patients with knee osteoarthritis (4 males, 21 females). The femorotibial angle was evaluated on standing anteriorposterior radiographs and recorded at pre- and post-arthroplasty. Using three-dimensional motion capture, the gait parameters (cadence, walking speed, stride length, step length, step width), range of motion of lower extremity joints (hip, knee, and ankle), and trunk movement parameters (angle, speed, and displacement) were measured and compared between the pre- and 4th post-arthroplasty week. RESULTS: The femorotibial angles of the arthroplasty side were improved from an average of 189° to 175° after arthroplasty. At the 4th post-arthroplasty week, the range of motion of the hip and knee flexion, hip adduction on the arthroplasty side, and ankle dorsiflexion on the non-arthroplasty side were significantly increased compared to pre-arthroplasty. Among gait parameters, only the stride length increased significantly. Regarding the trunk movement in the coronal plane, the maximal trunk speed to the non-arthroplasty side and maximal trunk displacement to the arthroplasty side were both reduced in a medio-lateral direction; the upward maximal trunk speed on the arthroplasty side increased and the maximal trunk displacement on the non-arthroplasty side decreased significantly in an up-down direction. CONCLUSION: The recovery of hip adduction during the standing phase caused by improvement of knee alignment contributed the reduction of trunk movement to the operated side. In the early post-arthroplasty period, the reduction of trunk movement in the coronal plane is beneficial to maintain trunk balance and prevent falls. Functional recovery of the lower extremities is a long-term process, and sustained functional training is necessary.

In vitro and in vivo AM and PL tunnel positioning in anatomical double bundle anterior cruciate ligament reconstruction.

BACKGROUND: There have been few studies investigating the correct anatomical femoral and tibial tunnel placement in double bundle anterior cruciate ligament (ACL) reconstruction. OBJECTIVE: To compare anteromedial (AM) and posterolateral (PL) tunnel positions in anatomical double bundle ACL reconstruction in human cadaver and patient knees. MATERIALS AND METHODS: Fifteen fresh-frozen non-paired adult human knees and 27 patients (27 knees) were evaluated. In the cadaver knees, AM and PL bundles were identified by their difference in tension patterns. Their femoral centers were marked with a K-wire, and cut from the femoral insertion site. After this, each bundle was divided at the tibial side. The center of each bundle insertion was again marked with a K-wire, and 5-7-mm tunnels were drilled with transportal or outside-in technique. In patient knees, each tunnel was made according to the native ACL foot print and bony landmarks using transtibial technique (n = 5) and transportal technique (n = 22). Tunnel placement was evaluated using a C-arm X-ray device and 3D CT. For the femoral side assessment, Bernard and Hertel's technique was used. For the tibial side assessment, Amis and Jakob's technique was used. RESULTS: The femoral AM tunnel in the cadaver knees was placed in a significantly deeper position when compared to patient knees. There was no significant difference in the AM vertical placement or in the PL tunnel placement in the femur. No significant differences were observed in the tibial tunnel placements between cadaver and patient knees. CONCLUSION: In vivo positioning of the femoral AM bundle differed significantly from the in vitro positioning.

Clinical analysis of risk factors for falls in home-living stroke patients using functional evaluation tools.

OBJECTIVES: To identify risk factors associated with falls in home-living stroke patients and to predict falls using patient information and functional evaluation tools. DESIGN: Cohort study. SETTING: Community. PARTICIPANTS: We recruited 101 home-living stroke patients who had hemiparesis and could walk independently with or without supporting devices. Disease duration ranged from 1 to 22 years (mean, 6.1 y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The score of each item of the Stroke Impairment Assessment Set (SIAS), and the FIM instrument, sex, age, duration of disease, stroke type, affected side of the body, frequency of rehabilitation, use of sedatives, and Mini-Mental State Examination score were evaluated and the occurrence of falls was observed prospectively for 12 months. RESULTS: Forty-five (44.6%) participants fell, 20 of whom fell repeatedly. A logistic model for predicting falls was refined until it included 4 predictors: memory score on the FIM, range of motion of the lower extremities on the SIAS, duration of disease, and affected side. The predictive value of the logistic model was 86.7%. CONCLUSIONS: Evaluation tools were useful for predicting falls and devising preventive strategies in the high-risk group of home-living stroke patients.

Impact of a Multidisciplinary Round Visit for the Management of Dysphagia Utilizing a Wi-Fi-Based Wireless Flexible Endoscopic Evaluation of Swallowing.

OBJECTIVES: The management of dysphagia requires a multidisciplinary approach, especially in large-scale hospitals. We introduce a novel protocol using a Wi-Fi-based flexible endoscopic evaluation of swallowing (FEES) system and aim to verify its effectiveness in evaluation and rehabilitation of inpatients with dysphagia. METHOD: We conducted novel Wi-Fi-based FEES at the bedside using 3 iPads as monitors and recorders. Functional outcomes of swallowing in 2 different hospitals for acute care with conventional wired or wireless FEES were compared retrospectively. RESULTS: Using the wireless system, we could visit more patients in a short period of time. Furthermore, a large multidisciplinary team was able to be present at the bedside, which made it easy to hold discussions and rapidly devise appropriate rehabilitation strategies. Aspiration pneumonia recurred in a few cases following our intervention with wireless FEES. Functional oral intake score was significantly increased following the intervention. Moreover, the number of deaths during hospitalization using wireless FEES evaluation was lower than those observed using the conventional system. CONCLUSION: Wi-Fi-based wireless FEES system, the first of its kind, allowed our multidisciplinary team to easily and effectively assess inpatients with dysphagia by facilitating simple examinations and intensive transprofessional discussions for patient rehabilitation.

A novel skull clamp positioning system and technique for posterior cervical surgery: clinical impact on cervical sagittal alignment.

A prospective radiographic study.The purpose of this study was to analyze whether a novel skull clamp positioning system and technique is useful for obtaining good, quantitative cervical sagittal alignment during posterior cervical surgery.Different surgical procedures depend on cervical spine positioning. However, maneuver of the device and cervical position depends on the skill of the operator.This study included 21 male and 10 female patients with cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament of the cervical spine, undergoing posterior cervical surgery using the novel skull clamp positioning system. The average patient age was 68.6 years (range: 56-87 years). The novel system has a scale to adjust the neck position and to enable intended cervical sagittal alignment. First, the patient was placed on the operating table in the prone position with preplanned head-neck sagittal alignment (neutral position in general). The head was rotated sagittally, and the head was positioned in the military tuck position with the novel device that was used to widen the interlaminar space. After completing the decompression procedure, the head was rotated again back to the initial preplanned position. During this position change, the scale equipped with the device was useful in determining accurate positions. The C0-C1, C0-C2, C1-C2, C2-C7, and C0-C7 angles were measured on lateral radiographs taken pre-, intra-, and postoperatively.This novel system allowed us to obtain adequate, quantitative cervical sagittal alignment during posterior cervical surgery. There were no clinically significant differences observed between the pre- and postoperative angles for C1-C2 and C2-C7.Sagittal neck position was quantitatively changed during posterior cervical surgery using a novel skull clamp positioning system, enabling adequate final cervical sagittal alignment identical to the preplanned neck position.