Normative Data of Grip Strength and Pinch Strength in the Indian Population.

Background There is no normative study of transregional grip strength data available from India. Hence, a multicenter study is designed to obtain reference value. Materials and Methods This is a prospective observational study conducted as a part of the Indian normative data project of the Indian Society for Surgery of the Hand. The study included three participating centers: one from the northern part and two from the southern part. Certified calibrated Jamar dynamometer and Jamar pinch gauge were used to measure the grip strength, key pinch strength, tip pinch strength, and tripod pinch strength as per the guidelines of the American Society of Hand Therapists. Results A total of 1,019 volunteers in the age group of 18 to 60 years were studied. The mean grip strength in males and females was 38.18 and 24.06 kg, respectively. The mean key pinch strength was 8.52 kg in males and 5.97 kg in females. The mean tip pinch strength was 4.86 kg in males and 3.59 kg in females. The mean tripod pinch strength was 5.41 kg in males and 4.16 kg in females. Conclusions All four strengths were lower in value when compared with American and other populations. The men had more strength than women. There was no relation to hand dominance. There was a correlation for age and height but no correlation with body mass index (BMI).

Quantification of hand function by power grip and pinch strength force measurements in ulnar nerve lesion simulated by ulnar nerve block.

INTRODUCTION: In the assessment of hand and upper limb function, grip strength is of the major importance. The measurement by dynamometers has been established. PURPOSE OF THE STUDY: In this study, the effect of a simulated ulnar nerve lesion on different grip force measurements was evaluated. METHODS: In 25 healthy volunteers, grip force measurement was done by the JAMAR dynamometer (Fabrication Enterprises Inc, Irvington, NY) for power grip and by a pinch strength dynamometer for tip pinch strength, tripod grip, and key pinch strength. STUDY DESIGN: A within-subject research design was used in this prospective study. Each subject served as the control by preinjection measurements of grip and pinch strength. Subsequent measurements after ulnar nerve block were used to examine within-subject change. RESULTS: In power grip, there was a significant reduction of maximum grip force of 26.9% with ulnar nerve block compared with grip force without block (P < .0001). Larger reductions in pinch strength were observed with block: 57.5% in tip pinch strength (P < .0001), 61.0% in tripod grip (P < .0001), and 58.3% in key pinch strength (P < .0001). DISCUSSION: The effect of the distal ulnar nerve block on grip and pinch force could be confirmed. However, the assessment of other dimensions of hand strength as tip pinch, tripod pinch and key pinch had more relevance in demonstrating hand strength changes resulting from an distal ulnar nerve lesion. CONCLUSIONS: The measurement of tip pinch, tripod grip and key pinch can improve the follow-up in hand rehabilitation. LEVEL OF EVIDENCE: II.

Effects of glovebox gloves on grip and key pinch strength and contact forces for simulated manual operations with three commonly used hand tools.

This study examined the effects of glovebox gloves for 11 females on maximum grip and key pinch strength and on contact forces generated from simulated tasks of a roller, a pair of tweezers and a crescent wrench. The independent variables were gloves fabricated of butyl, CSM/hypalon and neoprene materials; two glove thicknesses; and layers of gloves worn including single, double and triple gloving. CSM/hypalon and butyl gloves produced greater grip strength than the neoprene gloves. CSM/hypalon gloves also lowered contact forces for roller and wrench tasks. Single gloving and thin gloves improved hand strength performances. However, triple layers lowered contact forces for all tasks. Based on the evaluating results, selection and design recommendations of gloves for three hand tools were provided to minimise the effects on hand strength and optimise protection of the palmar hand in glovebox environments. PRACTITIONER SUMMARY: To improve safety and health in the glovebox environments where gloves usage is a necessity, this study provides recommendations for selection and design of glovebox gloves for three hand tools including a roller, a pair of tweezers and a crescent wrench based on the results discovered in the experiments.

Comparison of simulated key pinch after three surgical procedures for trapeziometacarpal osteoarthritis: a cadaver study.

We performed a cadaver study using 18 fresh-frozen adult forearms and hands to compare the tendon loads required to generate progressively greater key pinch (0.5 kg to 2 kg) after three different surgical procedures to treat trapeziometacarpal osteoarthritis: isolated trapeziectomy, trapeziectomy followed by ligament reconstruction with tendon interposition and total joint arthroplasty using a Touch® implant. Thumb pinch was simulated by loading the main actuator tendons involved in the key pinch. Six specimens were randomly assigned to each of the three surgical procedure groups. Measurements were made before and after the joint surgery. Specimens that underwent trapeziectomy with or without ligament reconstruction with tendon interposition required significantly higher tendon loads than those with the implant to achieve the same pinch force. There was no significant difference between the isolated trapeziectomy and ligament reconstruction groups. Using the implant resulted in similar median tendon loads compared with those of the intact sample. Total joint arthroplasty with a Touch® prosthesis may yield a superior biomechanical profile in which the tendon loads needed to achieve a certain key pinch force are lower and better distributed between the actuator muscles compared with trapeziectomy with or without ligament reconstruction.

Assessment of hand-grip and key-pinch strength at three arm positions among healthy college students: Dominant versus non-dominant hand.

OBJECTIVE: Grip strength is important for independent self-care and is a predictor of functional decline. This study aimed to determine if healthy individuals would demonstrate different hand-grip and key-pinch strengths at three different arm positions and in comparisons between dominant and non-dominant hands. METHODS: A total of 61 right-hand-dominant male college students aged 19-23 years were consecutively recruited from the College of Medical Rehabilitation Sciences. Three researchers performed the measurements. All tests were performed with the JAMAR® hand-grip dynamometer handle set in its second position. Participants were instructed to squeeze the handle of the hand-grip dynamometer in the 90° elbow flexion, 90° shoulder flexion, and arm dangled positions. For assessment of key-pinch strength, every participant had to squeeze the thumb pad against the lateral aspect of the middle phalanx of the index finger. Key-pinch strength was measured in the same positions used for assessment of hand-grip strength. Participants were blinded for the outcome measurements. The significance level was set at p < 0.05. RESULTS: The hand-grip and key-pinch strengths did not show significant effects. Comparison of right and left hand-grip strengths also showed insignificant differences. However, the key-pinch strength showed a significant increase in favour of the dominant hand. CONCLUSIONS: Clinicians can choose any upper-extremity position to measure hand-grip and key-pinch strength. Furthermore, clinicians should aim to maintain and restore almost equal scores for hand-grip and pinch strength of the dominant and non-dominant hands to ensure better hand function.

Toe Gap Force is Related to Ultrasonic Parameter of Calcaneus Bone Status in General Population.

BACKGROUND: Elucidating the relation between bone health condition and muscle strength can provide useful knowledge for Japan's super-aged society. This study ascertained the Speed Of Sound (SOS) of the calcaneus and upper and lower limb muscle strength in a general population. METHODS: Medical examinations were conducted of 277 adult residents (100 men, 177 women; average age 67.1 years) of a mountain village. Bilateral hand grip and hand key pinch strength were measured. Hip abductor muscle strength was measured using a hand-held dynamometer. The pressure between the hallux and second toe (toe-gap force) was measured using a toe pressure measuring instrument. The Speed Of Sound (SOS) of the calcaneus was assessed using an ultrasound bone densitometer. Stepwise linear regression was used to identify the predictor of SOS using several factors as explanatory variables: gender, age, height, weight BMI, grip and key pinch power strength, hip abductor muscle strength, and toe-gap force in bilateral side. P values of < .05 were inferred as statistically significant. RESULTS: Significant positive correlation was found between the SOS and each of bilateral hand grip and hand key pinch strength, hip abductor muscle strength, and toe-gap force in all participants. Stepwise logistic regression revealed gender (ß coefficient= -0.32, p= .0001), age (ß coefficient=-0.53, p= .000), height (ß coefficient= -0.19, p= .03), and right toe-gap force (ß coefficient= 0.11, p= .027) as predictors of calcaneal SOS for all participants. CONCLUSION: Toe-gap force assessment might be more useful to predict calcaneal SOS than grip assessment in the general population.