Evaluating Core Muscle Strength for Transversus Abdominis Among Normal Individuals - An Observational Study

Background: Lack of control in deep muscles may result into poor segmental support even during activities of daily living in people with or without history of low back pain. This states the importance of muscular system in control of spinal stability. Aim: To evaluate and estimate core strength of lumbar region in normal individuals. Methods and Material: Cross sectional observational study with convenience sampling was carried out on 843 normal healthy individuals between the age group of 18 – 60 years. Core strength was estimated by pressure biofeedback unit with individual in prone formal test to assess transversus abdominis. Pressure reduction which was held at least up to 10 seconds was noted. The same procedure was repeated for three times and the best of the three repetitions was used for analysis. Statistical analysis: MedCalc version 19.7.4 was used. Reference ranges were calculated with 90% CI with non-parametric percentile method. Results: Reference range was 2 – 10 mmHg with median 9 mmHg for all the subjects between the age group of 18-60 years. Reference range for males (5 – 10 mmHg) was higher than females (2 – 10 mmHg) among this age group. Median for males and females was 10 mmHg and 6 mmHg respectively. Reference ranges was 5 – 10 mmHg for 18 – 30 years, 2 – 10 mmHg for 31 – 40 years and 41 – 50 years respectively and 2 – 9 mmHg for 51 – 60 years age groups. Conclusions: Reference range for the core strength of lumbar region among normal individuals as measured by pressure biofeedback unit is 2 – 10 mmHg. Key words: Core strength, Pressure biofeedback unit, Reference range, Transversus abdominis