ABSTRACT
Joint cracking involves a manipulation of the finger joints resulting in an audible crack. This study aimed to determine whether habitual knuckle cracking (KC) leads to an alteration in grip strength and metacarpal head (MH) cartilage thickness. Thirty-five habitual knuckle crackers (cracking their joints ≥5times/day) (20 M, 15 F, aged 19-27 years) and 35 age-, gender-, and body mass index-matched non-crackers were enrolled in the study. MH cartilage thickness was measured with ultrasound and grip strength was measured with an analog Jamar hand dynamometer. Grip strength was similar between groups (P>0.05). Habitual knuckle crackers had thicker MH cartilage in the dominant and non-dominant hands than those of the controls (P=0.038 and P=0.005, respectively). There was no correlation between MH cartilage thickness and grip strength in both groups (P>0.05). While habitual KC does not affect handgrip strength, it appears to be associated with increased MH cartilage thickness.
Subject(s)
Cartilage/diagnostic imaging , Finger Joint/physiology , Habits , Hand Strength/physiology , Metacarpal Bones/diagnostic imaging , Stress, Mechanical , Adult , Case-Control Studies , Female , Humans , Male , Muscle Strength Dynamometer , Ultrasonography , Young AdultABSTRACT
OBJECTIVE: The study aimed to assess tendon thickness in patients with chronic occupational lead exposure by using ultrasonography. METHODS: Twenty-seven male workers (mean age 32.9 ± 6.2 years, range 25-44 years) with occupational lead exposure and 27 age- and body mass index (BMI)-matched healthy male subjects (mean age 33.1 ± 5.6 years, range 25-44 years) were enrolled. Ultrasonographic measurements were obtained from the supraspinatus and Achilles tendons by using a linear probe (5-10 MHz). RESULTS: Mean Achilles tendon values at long axis (p = 0.034) and tendon cross-sectional area (p = 0.013) were significantly smaller in the lead-exposed group than the control group. On the other hand, no significant difference was found regarding the thickness of the supraspinatus tendon (p > 0.05). CONCLUSION: Our preliminary results imply that subjects with occupational lead exposure have smaller Achilles tendons than healthy subjects. Chronic lead exposure may affect the tendons due to reduction of collagen synthesis. Further studies are definitely needed to confirm our initial findings.
