This 1984 prospective cohort study followed 928 Danish adults after a standardized physical examination to determine which measurements predicted new or recurrent low back trouble over 12 months. It introduced the isometric back extensor endurance test — now called the Sørensen test — as a formal clinical tool. The central question: can physical measurements taken today predict who gets low back pain next year?
When a male patient comes in asking how to prevent his first episode of back pain, the Sørensen test gives you an objective answer: men with lower endurance times prospectively developed LBT at higher rates in this foundational cohort.
This paper is why spine rehabilitation programs target endurance before strength. The finding that weak muscles and poor flexibility are residual signs of prior episodes — not independent predictors. Means treating those deficits alone will not prevent a first occurrence.
For recurrent LBT, no single physical measurement outperformed one clinical variable: how recently the last episode occurred. The closer the last episode, the higher the recurrence risk. Use that history as your primary prognostic tool.
The hypermobility finding is the counterintuitive pearl worth remembering: in men, a more mobile lumbar spine predicted LBT, not a stiff one. This challenges the reflex to reassure hypermobile patients that their flexibility is protective.
This 1984 prospective cohort study followed 928 Danish adults after a standardized physical examination to determine which measurements predicted new or recurrent low back trouble over 12 months. It introduced the isometric back extensor endurance test — now called the Sørensen test — as a formal clinical tool. The central question: can physical measurements taken today predict who gets low back pain next year?
When a male patient comes in asking how to prevent his first episode of back pain, the Sørensen test gives you an objective answer: men with lower endurance times prospectively developed LBT at higher rates in this foundational cohort.
This paper is why spine rehabilitation programs target endurance before strength. The finding that weak muscles and poor flexibility are residual signs of prior episodes — not independent predictors. Means treating those deficits alone will not prevent a first occurrence.
For recurrent LBT, no single physical measurement outperformed one clinical variable: how recently the last episode occurred. The closer the last episode, the higher the recurrence risk. Use that history as your primary prognostic tool.
The hypermobility finding is the counterintuitive pearl worth remembering: in men, a more mobile lumbar spine predicted LBT, not a stiff one. This challenges the reflex to reassure hypermobile patients that their flexibility is protective.