Roles of flexion-extension radiograph bracket in assessing lumbar instability in patients with degenerative lumbar diseases

English Keywords:Degenerative lumbar diseases  X-ray  Flexion-extension  Radiograph bracket  Lumbar instability

English Abstract:

  【Abstract】 Objectives: To investigate the roles of flexion-extension radiograph bracket(FERB) in evaluating lumbar stability in patients with lumbar degenerative diseases. Methods: A total of 63 inhospital patients with L4/5 degenerative lumbar diseases in our hospital participated voluntarily in the study from May 2021 to January 2022. There were 35 males and 28 females, aged 33-84 years(56.7±14.6 years) old. Routine standing lateral flexion-extension radiographs(LFERs) and FERB-aided LFERs(FERB-LFERs) were taken after admissions of patients. Sagittal translation(ST), segmental angulation(SA), posterior opening(PO), and changes of lumbar lordosis(CLL) were measured for comparisons between LFER and FERB-LFER. Lumbar instability(LI) was defined as ST≥3mm or SA≥15° on flexion-extension radiographs, or PO≥5° on flexion radiographs. The detection rates of LI by the two photography methods of X-ray films were calculated and compared. Results: All the 63 patients completed the two methods of photography, respectively. 61 patients felt radiograph aided with FERB more comfortable, and the other 2 patients with severe waist pain(unbearable pain when stretching or bending the waist slightly) felt no significant difference between the two methods. On the lumbar FERB-LFERs, the ST was 2.31mm(0, 3.23), SA was 9.75°±5.12°, PO was -1.0°(-5.0°, 1.0°), CLL was 34.81°±15.01°. On the routine LFERs, the ST was 0.5mm(0, 1.42), SA was 5.67°±3.98°, PO was -1.0°(-4.0°, 0°), and CLL was 25.35°±13.88°. ST, SA, PO and CLL on the FERB-LFERs were significantly higher than those on routine LFERs(P<0.05). LI was detected in 24 cases(38.1%) on the FERB-LFERs, and only in 5 cases(7.9%) on the routine LFERs. The detection rates between the two photography methods were statistically different(P<0.05). Conclusions: Compared with routine lateral flexion-extension radiographs, photography aided with the flexion-extension radiograph bracket can standardize the procedures, reduce the discomfort of patients during the process of radiographs, and increase the detection rate of lumbar indisability.