Developing a Novel Prosthetic Hand with Wireless Wearable Sensor Technology Based on User Perspectives: A Pilot Study.

Myoelectric hands are beneficial tools in the daily activities of people with upper-limb deficiencies. Because traditional myoelectric hands rely on detecting muscle activity in residual limbs, they are not suitable for individuals with short stumps or paralyzed limbs. Therefore, we developed a novel electric prosthetic hand that functions without myoelectricity, utilizing wearable wireless sensor technology for control. As a preliminary evaluation, our prototype hand with wireless button sensors was compared with a conventional myoelectric hand (Ottobock). Ten healthy therapists were enrolled in this study. The hands were fixed to their forearms, myoelectric hand muscle activity sensors were attached to the wrist extensor and flexor muscles, and wireless button sensors for the prostheses were attached to each user's trunk. Clinical evaluations were performed using the Simple Test for Evaluating Hand Function and the Action Research Arm Test. The fatigue degree was evaluated using the modified Borg scale before and after the tests. While no statistically significant differences were observed between the two hands across the tests, the change in the Borg scale was notably smaller for our prosthetic hand (p = 0.045). Compared with the Ottobock hand, the proposed hand prosthesis has potential for widespread applications in people with upper-limb deficiencies.

Association between Sarcopenia and Balance in Patients Undergoing Inpatient Rehabilitation after Hip Fractures: A Retrospective Cohort Study.

Background and Objectives: Sarcopenia is characterized by a decline in skeletal muscle mass, strength, and function and is associated with advancing age. This condition has been suggested as a factor that negatively influences the functional outcomes of patients with hip fractures. However, the association between sarcopenia and balance impairment in patients undergoing inpatient rehabilitation after hip fractures remains unclear. In this retrospective cohort study, we aimed to investigate the impact of sarcopenia on balance outcomes in patients undergoing inpatient rehabilitation following hip fractures. Materials and Methods: Baseline sarcopenia was diagnosed using skeletal muscle mass index and handgrip strength, with cut-off values recommended by the Asian Working Group for Sarcopenia. The primary outcome was balance, which was assessed using the Berg Balance Scale (BBS) at the time of discharge. A multiple linear regression model analyzed the association between sarcopenia and balance. The model was adjusted for age, sex, comorbidities, and cognitive function. Results: Among the 62 patients (mean age: 78.2; sex: 75.8% women), 24.2% had sarcopenia. Patients with sarcopenia had significantly lower BBS scores than did those without sarcopenia (41 vs. 49 points, p = 0.004). Multiple linear regression analysis revealed that baseline sarcopenia was independently associated with BBS scores at discharge (ß = -0.282, p = 0.038). Conclusions: Following inpatient rehabilitation, patients with baseline sarcopenia had inferior balance outcomes than did those without sarcopenia at discharge. Sarcopenia should be assessed on admission to consider and provide additional care for those with a higher risk of poor functional outcomes. More studies are needed to investigate the association between sarcopenia and functional outcomes, examine the impact of sarcopenia treatment on these outcomes, and reduce the risk of recurrent falls and fractures in patients with hip fractures.

Factors Associated with Discharge Destination in Patients with Bone Metastases.

Background and Objectives: The discharge destination of patients with advanced cancer correlates with their quality of life. Patients with bone metastases often undergo lifestyle changes owing to pain and activity limitations. However, there are few reports on factors related to the discharge destination of patients with bone metastases. This study aimed to elucidate the factors associated with the discharge destination of patients with bone metastases. Methods: This study included 278 patients diagnosed with bone metastases who were admitted to the University of Tsukuba Hospital between April 2015 and March 2020. This study examined discharge destination, occurrence of skeletal-related events (SREs), primary lesions, locations of bone metastases, functional ambulation categories (FAC), age, and length of hospital stay. A binomial logistic regression analysis was conducted to compare the home and non-home discharge groups. Results: Of the 278 patients, 142 were discharged to home, 89 were discharged to somewhere other than home (non-home), and 47 died. The discharge destination was associated with spinal cord compression (SCC) (odds ratio [OR] 3.37, 95% confidence interval [CI] 1.35-8.43), hypercalcemia (OR 6.84, 95% CI 1.09-42.76), and FAC at admission (OR 0.45, 95% CI 0.35-0.58). The admission FAC cut-off value for discharge to home was determined to be 1.5 (area under the curve [AUC] 0.79, sensitivity 77.5%, specificity 68.5%). Conclusions: Factors associated with discharge destination were identified. The walking ability required for discharge to home was FAC 1.5, meaning that the patient needed one person to assist in preventing falls when walking on level ground. A cut-off value for FAC on admission for predicting outcomes was identified, suggesting the importance of gait ability assessment on admission.

Feasibility and Efficacy of the Newly Developed Robotic Hybrid Assistive Limb Shoulder Exercises in Patients with C5 Palsy during the Acute Postoperative Phase.

Background and Objectives: Although postoperative C5 palsy is a frequent complication of cervical spine surgery, no effective therapeutic rehabilitation approach has been established for postoperative C5 palsy. The purpose of this study was to find evidence confirming the effectiveness and feasibility of robotic Hybrid Assistive Limb (HAL) shoulder exercises for C5 palsy. Materials and Methods: In this before-after, uncontrolled case series clinical study, we performed a mean of 11.7 shoulder training sessions using a shoulder HAL immediately after the onset of C5 palsy in seven shoulders of six patients who developed postoperative C5 palsy and had difficulty raising their shoulder during the acute postoperative phase of cervical spine surgery. Shoulder HAL training was introduced as early as possible after evaluating the general condition of all inpatients who developed C5 palsy. Patients underwent shoulder abduction training using shoulder HAL on an inpatient and outpatient basis at 2-week or 1-month intervals. Adverse events associated with shoulder HAL training were investigated. The shoulder abduction angle and power without the shoulder HAL were evaluated before shoulder HAL usage, at every subsequent session, and upon completion of all sessions. Results: Severe adverse events due to shoulder HAL training were not reported. After completion of all shoulder HAL sessions, all patients showed improved shoulder elevation, while shoulder abduction angle and power improved over time. Conclusions: Shoulder elevation training with HAL in patients in the acute stage of postoperative C5 palsy has the potential to demonstrate improvement in shoulder joint function with a low risk of developing severe adverse events.

Passive Exoskeleton with Gait-Based Knee Joint Support for Individuals with Cerebral Palsy.

Cerebral palsy is a neurological disorder with a variety of symptoms that can affect muscle coordination and movement. Crouch gait is one such symptom that is defined as excessive knee flexion accompanied by a crouched posture. This paper introduces a passive exoskeleton to support the knee joint during stance of individuals with cerebral palsy that are affected by crouch gait. The exoskeleton utilizes a hydraulic disc brake mechanism that is actuated only by the body weight and gait of the wearer to provide a braking torque at the knee joint. This passive, gait-based control method aims to offer a compact, lightweight, and simple alternative to existing exoskeletons. Preliminary experiments were conducted to verify the mechanics, safety, and braking capabilities of the device with healthy participants. A pilot study with an individual with cerebral palsy was then conducted. The individual with cerebral palsy showed a reduction in hip joint angle when using the device (18.8∘ and 21.7∘ for left and right sides, respectively). The muscle co-activation index was also reduced from 0.48 to 0.24 on the right side and from 0.17 to 0.017 on the left side. However, changes such as activation timing and device training need to be improved to better support the user.

Postoperative Acute-Phase Gait Training Using Hybrid Assistive Limb Improves Gait Ataxia in a Patient with Intradural Spinal Cord Compression Due to Spinal Tumors.

Sensory ataxia due to posterior cord syndrome is a relevant, disabling condition in nontraumatic spinal cord dysfunction. Ataxic gait is a common symptom of sensory ataxia that restricts activities of daily living. A 70-year-old woman with severe sensory disturbance was diagnosed with intradural extramedullary spinal cord tumors found in the thoracic spine region (T8). Surgical management of the tumors was performed. The patient received gait training 20 days after surgery (postoperative acute phase) using a hybrid assistive limb (HAL). HAL is a wearable exoskeleton cyborg that provides real-time assistance to an individual for walking and limb movements through actuators mounted on the bilateral hip and knee joints. Walking ability was assessed using the 10 m walking test, which included evaluating walking speed, step length, and cadence in every session. To evaluate the immediate effects of HAL training, walking speed and step length were measured before and after the training in each session. During the 10 m walking test, gait kinematics and lower muscle activity were recorded using a motion capture system and wireless surface electromyography before the first session and after completion of all HAL sessions. After the HAL training sessions, improvement in the patient's gait performance was observed in the gait joint angles and muscle activity of the lower limb. After 10 training sessions, we observed the following changes from baseline: walking speed (from 0.16 m/s to 0.3 m/s), step length (from 0.19 m to 0.37 m), and cadence (from 50.9 steps/min to 49.1 steps/min). The average standard deviations of the knee (from right, 7.31; left, 6.75; to right, 2.93; p < 0.01, left, 2.63; p < 0.01) and ankle joints (from right, 6.98; left, 5.40; to right, 2.39; p < 0.01, left, 2.18; p < 0.01) were significantly decreased. Additionally, walking speed and step length improved immediately after completing all the HAL training sessions. This suggests that HAL gait training might be a suitable physical rehabilitation program for patients with sensory ataxia causing dysfunctional movement of the lower limb.

Development of a New Ankle Joint Hybrid Assistive Limb.

Foot and ankle disabilities (foot drop) due to common peroneal nerve palsy and stroke negatively affect patients' ambulation and activities of daily living. We developed a novel robotics ankle hybrid assistive limb (HAL) for patients with foot drop due to common peroneal nerve palsy or stroke. The ankle HAL is a wearable exoskeleton-type robot that is used to train plantar and dorsiflexion and for voluntary assistive training of the ankle joint of patients with palsy using an actuator, which is placed on the lateral side of the ankle joint and detects bioelectrical signals from the tibialis anterior (TA) and gastrocnemius muscles. Voluntary ankle dorsiflexion training using the new ankle HAL was implemented in a patient with foot drop due to peroneal nerve palsy after lumbar surgery. The time required for ankle HAL training (from wearing to the end of training) was approximately 30 min per session. The muscle activities of the TA on the right were lower than those on the left before and after ankle HAL training. The electromyographic wave of muscle activities of the TA on the right was slightly clearer than that before ankle HAL training in the resting position immediately after ankle dorsiflexion. Voluntary ankle dorsiflexion training using the novel robotics ankle HAL was safe and had no adverse effect in a patient with foot drop due to peroneal nerve palsy.

Characteristic MRI findings of shoulder, elbow, and wrist joints in wheelchair user.

OBJECTIVE: Wheelchair users frequently utilize their upper extremities for moving around in their daily life. Therefore, it is likely they may develop conditions of overuse in their joints, which could affect their activity and daily life. The purpose of this study is to clarify the actual conditions of the joints of wheelchair users using MRI. MATERIAL AND METHODS: Twenty-five wheelchair users and twenty able-bodied control volunteers participated in this study. We scanned MRI images of their right and left shoulders, elbows, and wrists. Two radiologists interpreted the images and made diagnoses for each of the joints. The number of diseases for each joint was compared between wheelchair users and able-bodied volunteers. RESULTS: The number of supraspinatus tendon tears was higher in wheelchair users than controls in the right (Rt.) (P < 0.05), left (Lt.) (P < 0.05), and bilateral (Bil.) (P < 0.05) shoulders. The number of elbow LP lesions (Rt. (P < 0.01), Lt. (P < 0.01), and Bil. (P < 0.05)) and the number of elbow lateral epicondylitis cases (Rt. [P < 0.05] and Lt. [P < 0.05]) were also higher in wheelchair users than that of control volunteers. Additionally, the number of wrist TFCC injuries in wheelchair users (Rt. [P < 0.01], Lt. [P < 0.01], and Bil. [P < 0.01]) was more than that of control volunteers. CONCLUSION: Our results suggest that there are several types of overuse injury in each joint. However, we hypothesize that these are not induced by driving wheelchairs, but instead by the "push up" movement characteristic for wheelchair users, according to the situations caused by each injury.

Rehabilitation training using a single-joint type hybrid assistive limb for the knee after anterior cruciate ligament reconstruction: an initial case report indicating safety and feasibility.

[Purpose] The aim of this report was to describe the safety, feasibility, and efficacy of rehabilitation by knee extension and flexion training using the knee single-joint hybrid assistive limb in a patient after anterior cruciate ligament reconstruction. [Participant and Methods] A 33 year-old male underwent an arthroscopic procedure for anatomic single-bundle anterior cruciate ligament reconstruction with a semitendinosus tendon autograft. Rehabilitation training using the knee single-joint hybrid assistive limb was initiated at postoperative week 18 and repeated weekly for 3 weeks. The patient performed five sets of the knee single-joint hybrid assistive limb-assisted knee-extension-flexion exercises per session at a frequency of 10 exercises/set. [Results] The peak extension torque at all velocities with the limb symmetry index was higher after the hybrid assistive limb intervention (post-intervention) than before using it (pre-intervention). Peak flexion torques at 60°/s and 300°/s of limb symmetry index were higher post-intervention than pre-intervention. The range of motion in extension and flexion improved from -2° (pre-intervention) to -1° (post-intervention) and from 124° to 133°, respectively. The Lysholm score increased from 58 (pre-intervention) to 94 (post-intervention). [Conclusion] The knee single-joint hybrid assistive limb can be used safely for anterior cruciate ligament reconstruction training, without any adverse events. Our results indicate that the knee single-joint hybrid assistive limb training may improve muscle function, effectively overcoming dysfunction.

Dropped Head Syndrome Attenuation by Hybrid Assistive Limb: A Preliminary Study of Three Cases on Cervical Alignment during Walking.

Background and Objectives: Dropped head syndrome (DHS) is characterized by apparent neck extensor muscle weakness and difficulty in extending the neck to raise the head against gravity. DHS affects forward vision and eating behavior, and hence impairs quality of life. However, standardized treatment of DHS has not yet been established. The purpose of this preliminary study is to seek for a possibility of effective non-surgical, conservative treatment for DHS, by applying a robotic treatment. Materials and Methods: A wearable exoskeleton type robot suit hybrid assistive limb (HAL) was applied to three patients with DHS. A course of HAL treatment included 10 sessions of gait training using HAL. One session lasted about an hour. Case 1 completed the course twice, the first time in two weeks (one session per day) and second time in 10 months (one session per month). Case 2 and Case 3 completed the course once in 10 weeks (one session per week) and in 6 months (one session per 2.5 weeks), respectively. Immediate and lasting effects of HAL on the reduction of cervical sagittal vertical alignment (SVA) during gait was evaluated using a motion capture system. Results: Case 1 showed improvement of cervical alignment during gait after the HAL courses of both different frequencies. Case 2 did not show improvement of cervical alignment during gait. Case 3 showed improvement of cervical kyphosis but not of cervical sagittal alignment during gait. Conclusions: The results of the preliminary study suggest that gait training using HAL may be an effective option of conservative treatment for a part of DHS patients. They also suggest that a lack of immediate effects on the cervical alignment and a lack of ability to perform compensatory trunk motion may indicate a non-responding patient. Generalization of the results requires further research with more cases.

Investigation of the Female Athlete Triad in Japanese Elite Wheelchair Basketball Players.

Background and objectives: Para-sports have become increasingly competitive, necessitating greater physical activity; secondary disorder prevention is therefore crucial. Among secondary disorders, the female athlete triad (FAT) is defined as low energy availability (EA), menstrual dysfunction, and low bone mineral density (BMD); although studied in able-bodied athletes, reports on female para-athletes are scarce. We retrospectively investigated the FAT in wheelchair basketball players in the Japanese national team. Materials and Methods: Thirteen female wheelchair basketball players (mean age: 28.9 ± 8.1 years) were enrolled. The medical history (underlying diseases, gynecological disorders, and stress fractures), athletic and sport-specific parameters (wheelchair basketball classification, and wheelchair usage conditions), hematological status (hemoglobin, iron, estradiol, progesterone, total P1NP, and TRACP-5b levels), nutritional status (total energy, protein, calcium, and iron intake), body composition (BMD and lean body mass (LBM)), and EA were assessed. Results: Two (15.4%) had pertinent gynecological histories and six (46.2%) had menstrual cycle disorders. Three (23.1%) experienced excessive menstrual flow and nine (69.2%) had menstrual pain. No stress fractures were reported. All laboratory data were within normal limits. Total energy and iron intakes based on age-specific requirements were 99.8% and 59.8%, respectively. Iron and hemoglobin levels correlated with menstrual flow (ρ = -0.63, p = 0.019 and ρ = -0.56, p = 0.046, respectively). The mean total BMD was 109.2%, and the mean EA (41.4 kcal/kg LBM) was lower than recommended levels. The leg BMD in spinal disorders was significantly lower than that in skeletal disorders (p = 0.003). The arm LBM was higher (150.6%) than that of age-matched controls. Conclusion: Among female wheelchair basketball players with FAT, the total BMD was comparable to that of age-matched controls; however, leg BMD in spinal disorders was significantly lower than that in skeletal disorders. Players with heavy menstrual flow had lower hemoglobin and iron levels. Further research is needed on the FAT to optimize health and sports performance among para-athletes.

Influence of Functional Classification on Skill Tests in Elite Female Wheelchair Basketball Athletes.

Background and objectives: Wheelchair basketball players are classified into four functional classes according to the player's "volume of action", characterized by trunk movement and stability. As this classification is based on a kinematic point of view, test items might be differentially affected by the functional classification level. We aimed to clarify field-based skill test items closely related to the functional classification level. Materials and Methods: Twenty-six female wheelchair basketball athletes (Japan National Team candidates) completed seven field-based skill tests (20 m sprint, agility T-test, figure-eight with a ball test, the Yo-Yo 10 m recovery test, and three types of maximal passes), and anthropometric measurements were applied. Results: Significant differences among the classification levels were found for one-hand maximal passes (baseball and hook passes) and the figure-eight with a ball test. Furthermore, performance in the 20 m sprint and 10 m Yo-Yo recovery tests significantly differed between classes 1 and 4. Conclusions: The test items most influenced by the classification levels were one-hand passes, which require trunk stability and balance not only in the horizontal plane, but also in the sagittal and frontal planes. Coaches should consider which test items are strongly affected by the functional classification level when assessing a player's performance.

A case of an elderly hip disarticulation amputee with rheumatoid arthritis who regained the ability to walk using a hip prosthesis.

[Purpose] We report a case of an elderly patient with rheumatoid arthritis who underwent hip disarticulation because of necrotizing fasciitis and regained the ability to walk independently with a prosthetic limb. [Participant and Methods] A 61-year-old female patient underwent right hip disarticulation due to severe necrotizing fasciitis of the right lower limb. Her chief complaint was that she was not able to walk inside her house or outdoors to perform instrumental activities of daily living. We applied a Canadian-type hip disarticulation prosthesis to the stump. The patient received in-hospital physical therapy, occupational therapy, and clinical psychology counselling for 145 days. As her hands and fingers were weakened by rheumatism, we made several modifications to the prosthesis to enable the patient to attach and detach it independently. [Results] The patient was able to use the prosthesis to walk continuously for 45 m, perform various housework duties, drive a car, and go out, thus accomplishing the desired daily activities. [Conclusion] Our patient, an elderly hip disarticulation amputee with rheumatoid arthritis, was able to walk independently using a prosthetic limb. The application of prosthetic limbs may be appropriate even for hip disarticulation amputees with comorbidities that make it difficult to acquire a prosthetic gait.

Relationship between somatosensory event-related potential N140 aberrations and hemispatial agnosia in patients with stroke: a preliminary study.

PURPOSE: The somatosensory event-related potential N140 is thought to be related to selective attention. This study aimed to compare the somatosensory event-related potential N140 in healthy subjects to that in patients with stroke to determine whether N140 and attentiveness are associated in patients with stroke with or without hemispatial agnosia. MATERIALS AND METHODS: Normal somatosensory event-related potential N140 values were determined using data from ten healthy subjects. Fifteen patients with stroke were divided into two groups based on the presence of hemispatial neglect. Somatosensory event-related potential N140 components were compared between the two groups. RESULTS: Stimulation of the affected limb in the hemispatial agnosia group resulted in significantly longer N140 latency at the contralateral vs. the ipsilateral electrode. This was the inverse of the relationship observed in normal subjects, with stimulation of the intact side in patients with hemispatial agnosia, and with stimulation of both the intact and affected sides in patients without agnosia. In the hemispatial agnosia group, the peak latency of N140 following stimulation of the affected side was significantly longer than it was following stimulation of the intact side and when compared to that in patients without agnosia. In addition, abnormal N140 peak latencies were observed at the Cz and ipsilateral electrodes in patients with hemispatial agnosia following stimulation of the intact side. CONCLUSIONS: These findings suggest that somatosensory event-related potential N140 is independently generated in each hemisphere and may reflect cognitive attention.

Mid-term results of concentrated autologous bone marrow aspirate transplantation for corticosteroid-associated osteonecrosis of the femoral head in systemic lupus erythematosus.

PURPOSE: We had previously established concentrated autologous bone marrow aspirate transplantation (CABMAT), a one-step, low-invasive, joint-preserving surgical technique for treating osteonecrosis of the femoral head (ONFH). This study aimed to evaluate the effects of CABMAT as a hip-preserving surgical approach, preventing conversion to total hip arthroplasty (THA) and femoral head collapse in patients with systemic lupus erythematosus (SLE). METHODS: Since 2003, 52 SLE patients (8 male, 44 female, 92 hips, mean age 35.3 (16-77) (years) were treated with CABMAT. The mean follow-up period was 5.5 (0.7-14) years. Conversion rate to THA and its predicting factors were analyzed. RESULTS: The overall conversion rate to THA was 29% (27/92). Conversion rate to THA was 0% (0/3), 0% (0/4), 22% (9/41), and 41% (18/44) in types A, B, C1, and C2, respectively. Conversion rate to THA was 26% (5/19), 26% (6/23), 28% (11/39), 44% (4/9), and 50% (1/2) in stages 1, 2, 3A, 3B, and 4, respectively. In multivariate logistic regression analysis, sex, body mass index (BMI), pre-operative type, and pre-operative stage were significantly correlated with conversion to THA. CONCLUSION: The conversion rate to THA was lower than that in the natural course and core decompression, but was higher than that seen in other bone marrow transplantation and osteotomy. Since sex, pre-operative type, and pre-operative stage were significantly correlated with conversion to THA, it is suggested that the higher proportion of women, advanced stage (stage 3A or above), and advanced type (type C or above) in this study affected the THA conversion rate.

Comparison of sleep status among three Japanese national wheelchair basketball teams.

[Purpose] Sufficient sleep is required for maximal performance and good mood. Japan has three national wheelchair basketball teams: Top male, Top female, and Under-23 (U23) male teams. Using these team members as model, this study investigated the difference of sleep status of wheelchair basketball players by age and gender. [Subjects and Methods] There were 44 participants: 14 in the Top male team (29.5 ± 5.2 years), 18 in the Top female team (30.6 ± 9.2 years), and 12 in the U23 team (19.1 ± 2.0 years). Sleep status was assessed with the Pittsburgh Sleep Quality Index (PSQI); higher scores indicate poor sleep quality. [Results] PSQI scores in the Top male and female teams were higher than in the U23 team. The Top teams showed shorter sleep duration and worse sleep efficacy than the U23 team. Time spent in bed and sleep duration in the female team were shorter than in the Top male and U23 teams. More male players reported "feel too hot" as the reason for sleep disturbance than female players. [Conclusion] Players in the Top Japanese national wheelchair basketball teams had poorer sleep status than U23 players. Among female players, the reason for insomnia was less sleep duration. For males, the reason for insomnia was "feel too hot."

Age-dependent changes in dynamic standing-balance ability evaluated quantitatively using a stabilometer.

[Purpose] The efficacy of a stabilometer-based index of postural stability (IPS) as an indicator of dynamic balance ability was investigated. [Subjects and Methods] Using a stabilometer, we calculated the IPS in 583 healthy subjects (178 males, 405 females) under two conditions (open eyes/hard surface, OE/HS; closed eyes/soft surface, CE/SS). [Results] Results revealed a negative relation between IPS and age. IPS (OE/HS) began to decrease at middle-age (40-60 years old), and then decreased more rapidly during elderly ages (>60 years old). On the other hand, IPS (CE/SS) decreased linearly with increasing age. There was no gender difference between the two IPSs. [Conclusion] These results suggest that IPS can evaluate balance ability quantitatively and without a ceiling effect. It was concluded that IPS (OE/HS) indicates comprehensive balance ability, while IPS (CE/SS) reveals balance ability without compensation by visual acuity and plantar superficial sense.

Correlation between sleep and psychological mood states in female wheelchair basketball players on a Japanese national team.

[Purpose] Although some studies suggest the importance of getting adequate sleep for enhancing mood, there is not yet sufficient evidence on the relationship between sleep and mood states in athletes, especially for athletes with physical disability. The purpose of this study is to reveal relationships between sleep and psychological mood states in female wheelchair basketball players. [Subjects and Methods] Seventeen female wheelchair basketball players (30.9 ± 9.4 years old) on a Japanese national team participated. Sleep states were assessed with the Pittsburgh Sleep Quality Index (PSQI), and mood states with the Japanese version of the Profile of Mood States short form (POMS-SF). Spearman's rank correlations were computed. [Results] The mean PSQI score was 5.4 ± 2.6 points, and 9 athletes (52.9%) exceeded the cutoff point (5.5) for insomnia. Higher sleep efficiency (rS=0.58), fewer sleep disturbances (rS=-0.58), and lower total PSQI score (rS=-0.51) were significantly correlated with higher vigor. Lower likelihood of daytime dysfunction was also significantly correlated with lower tension (rS=0.50). [Conclusion] Vigor was the mood state most frequently correlated with sleep variables. Because vigor is a known key psychological factor in optimal performance, the findings are valuable for wheelchair basketball players.