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Updated: Feb 12, 2026

Manual Muscle Testing: A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients
Published on: April 12, 2011
Grip strength as a simple method to predict postoperative delirium after lower extremity surgery in the elderly: a
Hyo Sung Kim1, Seok Kyeong Oh1, Young Sung Kim1
1Department of Anesthesiology and Pain Medicine, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea.
Background:
Grip strength (GS), an indicator of sarcopenia, declines with age and is associated with frailty, which increases the risk of postoperative delirium (POD). Assessing frailty in patients undergoing lower extremity surgery is challenging owing to limited mobility. We investigated whether GS, a simple screening tool, can independently predict POD and aimed to determine the most appropriate criteria for low GS in the Korean population.
Methods:
This prospective study included patients aged ≥ 65 years undergoing lower extremity surgery. Preoperative GS was measured, and sarcopenia was diagnosed according to the Asian Working Group for Sarcopenia (AWGS) cut-offs and three other established criteria for GS weakness. POD was assessed with the Confusion Assessment Method for the Intensive Care Unit. Receiver operating characteristic (ROC) curves were used to evaluate the sensitivity and specificity of low GS in predicting POD. Logistic regression analysis was performed to identify variables independently associated with POD.
Results:
GS was measured in 150 patients with a median age of 73 years. POD was diagnosed in 17 patients (11.3%), 13 of whom had low GS. Among the four sarcopenia criteria, the AWGS showed the highest area under the ROC curve (0.796). Of the variables analyzed-including age, American Society of Anesthesiologists class, body weight, intraoperative opioid use, and postoperative pain-only low GS was identified as an independent predictor of POD (odds ratio: 15.543, P < 0.001).
Conclusions:
GS is a simple, reliable measure that may serve as an independent predictor of POD in elderly undergoing lower extremity surgery.
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