Assessment of grip-motion characteristics in carpal tunnel syndrome patients using a novel finger grip dynamometer system.

BACKGROUND: Grip strength measurement is widely used in daily medical practice, and it has been reported that the grip strength decreases in patients with carpal tunnel syndrome (CTS). However, conventional grip dynamometers evaluate only the maximum power of total grip strength and cannot measure the time course of grip motion. In this report, we aimed to determine the grip characteristics of CTS patients by measuring the time course of each finger's grip motion and to analyze the relationship between finger grip strength and subjective symptoms using this new grip system. METHODS: The grip strength of each finger was measured using the new grip system that has four pressure sensors on the grip parts of each finger of the Smedley grip dynamometer. We analyzed the time course of grip motion and relationship between finger grip strength and subjective symptoms in 104 volunteer and 51 CTS hands. The Japanese Society for Surgery of the Hand version of the Carpal Tunnel Syndrome Instrument (CTSI-JSSH) and the Disability of Arm, Shoulder, and Hand questionnaire (DASH) were used as subjective evaluation scores. RESULTS: In the CTS group, the grip time with the index, middle, and ring fingers was longer, and the time at which strength was lost after reaching the maximum was earlier. Patients with severe subjective symptoms tended to not use the index and middle fingers during grip motion. CONCLUSIONS: This new system that measures each finger's grip strength at one time and record the time course of grip motion could quantify a patient's symptoms easily and objectively, which may contribute to the evaluation of hand function.

Presence of a family history and excessive pressure on the first toe pad during walking in female subjects with pincer nails.

Pincer nails (PN) are defined as a transverse overcurvature of the nail plate. Although there have been advancements in therapeutic approaches, the precise underlying mechanisms for the development of PN are still not fully understood. Currently, PN are assumed to develop due to lack of upward mechanical force on the toes. We developed a novel wireless device to observe detailed gait motion. We analyzed trends of gait motion in healthy individuals without PN, healthy individuals with PN without a family history of PN, and healthy individuals with PN and a family history of PN. We found that a family history of PN is an independent risk factor for PN, irrespective of gait motion. Moreover, healthy individuals with PN but without a family history of PN exhibit strong and concentrated pressure on the first toe pad during walking. In sum, a family history of PN and excess upward mechanical forces on the first toe pad during walking may be risk factors for the development of PN.

New wearable walking-type continuous passive motion device for postsurgery walking rehabilitation.

While total knee arthroplasty is useful for treating osteoarthritis of the knee, the success of this treatment depends on effective rehabilitation. The goal of this study was to develop an assistive device for post-total knee arthroplasty patients for walking rehabilitation and for shortening the hospitalization period. We developed a brace electronic assist system termed the knee assistive instrument for walking rehabilitation (KAI-R) to illustrate the need for training during postoperative rehabilitation. Sixteen osteoarthritis patients (1 male and 15 females; average age 68.9 years) who underwent total knee arthroplasty were analyzed before operation and 2-4 weeks after operation, and 25 healthy individuals (14 males and 11 females; average age 26.2 years) formed the control group. Based on the pre- and postoperative data on peak knee flexion angle, foot height, and walking velocity, we developed the KAI-R, which consists of an assistive mechanism for the knee joint, a hip joint support system, and a foot pressure sensor system and is driven by a CPU board that generates the walking pattern. We then tested the walking gait in seven healthy volunteers with and without KAI-R assistance. KAI-R increased the peak flexion angle of the knee and foot height in all seven volunteers; their range of motion of the knee joint was increased. However, KAI-R also decreased the walking velocity of subjects, which was explained by reaction delay and slightly compromised physical balance, which was caused by wearing the KAI-R. KAI-R is useful for gait improvement. In future studies, KAI-R will be investigated in a clinical trial for its ability for walking rehabilitation in post-total knee arthroplasty patients.