Comparison of two handgrip dynamometers in older adults before elective surgery

BACKGROUND: Handgrip strength is a useful measurement of muscle strength and has been proposed as a single predictor of postoperative outcomes in older adults. The aim of this study was to assess the correlation and concordance of Camry digital hand grip dynamometer (EH101) with gold standard Jamar® hydraulic handgrip dynamometer in older adults previous to elective surgery. METHODS: A cross-sectional study was conducted on patients ≥ 65 years old admitted to a Chilean private hospital for elective surgery between March 2018 and February 2019. Handgrip strength was assessed 2 times with each hand prior to surgery, using both the Jamar® dynamometer and the Camry digital dynamometer. The highest value of each dynamometer was used for analysis. RESULTS: We included a total of 220 patients (mean age 73.1 years old ± 6.3). Maximal handgrip strength averaged 26.9 kg ± 9.6 with the Camry dynamometer and 26.9 kg ± 9.7 with the Jamar® dynamometer in the right hand and 25.5 kg ± 9.5 with the Camry dynamometer and 25.7 kg ± 9.2 with the Jamar® dynamometer with the left hand. The difference between both measures did not differ significantly from 0, with Pearson correlation index of 0.95 and Lin’s concordance index of 0.95 (p < 0001). The Bland–Altman graphics show that 90% of the measures were inside the confidence limits, without systematic bias. CONCLUSION: Camry digital dynamometer is an inexpensive and valid device to measure handgrip strength in older adults previous to elective surgery, compared to the gold standard Jamar® hydraulic handgrip dynamometer.