Execution
- 1Position the patient standing with the lumbar spine exposed.
- 2Palpate and marks the midpoint between the posterior superior iliac spines.
- 3Mark a second point 15 cm superior to the PSIS midpoint.
- 4Measure the distance between the two marks in relaxed standing.
- 5Ask the patient to flex forward maximally with the knees straight and remeasures the distance.
Positive outcome
Abnormal findings: reduced excursion of the 15 cm interval, indicating reduced lumbar flexion mobility.
Expected measurement- Starting interval (PSIS midpoint to 15 cm superior): 15 cm
- Positive: restricted excursion vs expected values, opposite side context, or the patient’s previous baseline
There is no universal diagnostic cutoff for general low back pain. Treat the result as an impairment finding rather than a pathology classifier.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| Williams et al. (1993) | reliable for lumbar flexion and extension | NA | NA | NA | NA |
| Tousignant et al. (2005) | intra ICC 0.95; inter ICC 0.91 | NA | NA | NA | NA |
CommentThe modified-modified version removes the 5 cm inferior mark and is easier to standardize than the classic modified Schober method. Tousignant reported excellent reliability and moderate criterion validity, but this remains a measurement tool rather than a diagnostic test. It should be repeated with the same landmarks and examiner method whenever possible.
Low Clinical Value