A Reproducible and Inexpensive Method of Measuring Hip Abductor Strength

Abstract

The evaluation of hip abductor strength is useful in assessing of the outcome of hip surgery. Hand-held dynamometers are available, but they are less reliable in assessing hip abductor strength than some other muscle groups. We describe a new device designed to measure hip abductor strength, which is practical in a clinical setting. A system of constraints, pads and reference points was devised to make force measurements as little examiner-dependent as possible. Reproducibility was assessed in a controlled setting. The abductor strength of ten healthy young subjects (average age 28 years) was tested twice on each side by two independent examiners. Tests were performed in a supine position, eliminating the influence of gravity and examiner intervention. The results indicated high reproducibility, the maximal measurement uncertainty being within 1 N. Intra-class correlation coefficients ranged from 0.85-0.98 for intra-rater reproducibility, and 0.81-0.96 for inter-rater reporoducibility. The coefficient of variation was lower than 10%. The device described may be suitable for routine clinical assessment of patients after hip surgery.

Abductor muscle strengthening in THA patients operated with minimally-invasive anterolateral approach for developmental hip dysplasia

“…The device showed high reproducibility and low uncertainty (within 1 N), previously evaluated with a healthy population. 28…”

“…The device showed high reproducibility and low uncertainty (within 1 N), previously evaluated with a healthy population. 28 Functional outcome measures such as Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), HHS, 10 Metre Walk Test (10 mt WT), and patient satisfaction (12-Item Short-Form Health Survey ) were also used at each follow-up. The assessment was always carried out by the same physical therapist (LC).…”

Measuring hip muscle strength in patients with femoroacetabular impingement and other hip pathologies

“…They found high inter-and intra-observer reliability for all devices (ICC 0.88 to 0.95). Ford-Smith et al 16 and Traina et al 17 also found high ICC values for MDD devices (0.73 to 0.98).…”

“…Three studies 15 - 17 measured hip muscle strength using MDD. Click Fenter et al 15 compared three commercially available MDD devices when used on a population of ten participants over three separate days.…”

“…A number of methods of measuring muscle strength have been described such as MMT, HHD, MDD and EMG. 17 - 22 , 25 , 26 , 31 - 35 , 40 This causes difficulty in comparing the different studies as there are, at times, major differences in research methodology.…”