JMIR Publications

ABSTRACT

Background:

Physiological motion of the lumbar spine is a topic of interest for musculoskeletal health care professionals, since abnormal motion is believed to be related to lumbar complaints. Many researchers have described ranges of motion (ROM) for the lumbar spine, but only few mentioned specific motion patterns of each individual segment during flexion and extension, mostly comprising the sequence of segmental initiation in sagittal rotation. However, an adequate definition of physiological motion is still lacking. For the lower cervical spine, a consistent pattern of segmental contributions in a flexion-extension movement in young healthy individuals was described, resulting in a definition of physiological motion of the cervical spine.

Objective:

This study aimed to define the lumbar spines’ physiological motion pattern by determining the sequence of segmental contribution in sagittal rotation of each vertebra, during maximum flexion and extension in healthy male participants.

Methods:

Cinematographic recordings were performed twice in 11 healthy male participants, aged 18-25 years, without a history of spine problems, with a 2-week interval (T1 and T2). Image recognition software was used to identify specific patterns in the sequence of segmental contributions per individual by plotting segmental rotation of each individual segment against the cumulative rotation of segments L1 to S1. Intra-individual variability was determined by testing T1 against T2. Intraclass correlation coefficients (ICCs) were tested by re-evaluation of 30 intervertebral sequences by a second researcher.

Results:

No consistent pattern was found when studying the graphs of the cinematographic recordings during flexion. A much more consistent pattern was found during extension, especially in the last phase. It consisted of a peak in rotation in L3L4, followed by a peak in L2L3, and finally in L1L2. This pattern was present in 71% of all recordings. Sixty-four percent had a consistent pattern at both time points. Sequence of segmental contribution was less consistent in the lumbar spine than the cervical spine, possibly caused by differences in facet orientation, intervertebral discs, over-projection of the pelvis and muscle recruitment.

Conclusions:

In 64% of the recordings, a consistent motion pattern was found in the upper lumbar spine during the last phase of extension in asymptomatic young males. Physiological motion of the lumbar spine is a broad concept, influenced by multiple factors, which cannot be captured in a firm definition yet. Clinical Trial: ClinicalTrials.gov NCT03737227; https://clinicaltrials.gov/ct2/show/NCT03737227 Protocol Publication: JMIR Res Protoc 2020;9(2):e14741; doi: 10.2196/14741