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Biomedical subjects

Khai S Lam

Publications and source records attributed to Khai S Lam.

4 recordsLinked to original sources

Is there a role for selective anterior instrumentation in neuromuscular scoliosis?

Our objective was to report on the clinical and radiological outcome from a cohort of patients with neuromuscular scoliosis who underwent selective anterior single rod instrumentation for correction of thoraco-lumbar and lumbar scoliosis. Traditionally combined anterior release with long posterior instrumentation has been advocated for the treatment of neuromuscular scoliosis. Neuromuscular curves tend to be long and may have significant pelvic obliquity. However, certain neuromuscular curves with minimal pelvic obliquity may lend themselves to selective anterior correction thereby saving motion segments and allow continued ambulation for those patients. Nine patients with neuromuscular scoliosis underwent selective anterior instrumentation between 1994 and 2000. The mean follow up was 2 years and 9 months (range 24-55 months). The clinical outcome (including parent and caregiver satisfaction), radiological outcome (Cobb angle, apical vertebral translation, pelvic obliquity, truncal shift, thoracic kyphosis, lumbar lordosis, sagittal vertical axis) and complications are reported. Subjective outcome was excellent in six patients and good in three. All nine patients retained their ability to walk. There were no neurological or vascular complications. Supplementary posterior surgery was required in two patients. The mean pre-operative Cobb angle of 52 degrees (range 44-60) improved to 20 degrees (range 10-28) at 3 months, achieving Cobb angle correction of 61% and was 19 degrees (range 7-28) at final follow-up. The mean pre-operative compensatory curve of 31 degrees (range 20-42) spontaneously corrected to 18 degrees (range 14-24) at 3 months and was maintained at 18 degrees (range 10-26) at final follow up. The mean pre-operative pelvic obliquity of 7 degrees (range 0-14) corrected to 4 degrees (range 0-8) at 3 months and was 3 degrees (range 0-8) at final follow up. Selective anterior instrumentation and fusion in carefully selected patients with neuromuscular scoliosis (short flexible curves, minimal pelvic obliquity, pre-operative walkers, slow or non-progressive pathology) appears to have satisfactory clinical and radiological outcome at least in the short-term.

Adolescent↗

The Modic classification: inter- and intraobserver error in clinical practice.

STUDY DESIGN: A reliability study of the Modic classification. OBJECTIVE: To determine the reliability and reproducibility of the Modic classification for lumbar vertebral marrow changes. SUMMARY OF BACKGROUND DATA: In 1988, Modic et al described two degenerative stages of vertebral marrow and endplate morphology. These were type 1 (inflammatory phase) and type 2 (a fatty phase). Later in 1988, he added a third variety: type 3 where there was marked sclerosis adjacent to the endplates. No formal reliability or reproducibility studies had been performed on this Modic classification. METHODS: This study involved five independent observers of differing spinal experience using the Modic classification to grade 50 sagittal T1- and T2-weighted magnetic resonance imaging scans. The observers repeated the assessment at 3 weeks. Intra- and interobserver reliabilities were assessed using kappa statistics. RESULTS: There were 7 type 1, 40 type 2, 1 type 3, and 2 normal levels. The individual intraobserver agreement was substantial or excellent with kappa values ranging from 0.71 to 1. The overall interobserver agreement was excellent with a kappa value of 0.85. There was complete agreement in 78% of the levels, a difference of one type in 14% and a difference of two or more in 8% of levels. The level of experience of the observer did not correlate with a better score. CONCLUSIONS: We have shown that the classification is both reliable and reproducible. It is simple and easy to apply for observers of varying clinical experience. We therefore recommend its use in clinical research and practice.

Adult↗

Discitis.

Discitis is not an uncommon condition and can be potentially life threatening if diagnosed late. This article reviews recent publications and discusses the clinical presentation, pathoaetiology, diagnosis, treatment and pitfalls.

Age Distribution↗

The Adams classification for cadaveric discograms: inter- and intra-observer error in the clinical setting.

The Adams classification for discogram morphology is based on a cadaveric study. It provides the basis for several subsequent classifications proposed in the literature. However, little or no attention has been paid to its reproducibility in the clinical setting. The authors assessed the reliability of this classification using three independent observers of differing experience. One hundred and thirty-three discograms belonging to 71 patients with chronic low back pain were reviewed in a randomised and blinded manner. The morphological appearance at each discogram level was assessed and assigned a type according to the Adams classification. The exercise was repeated 3 weeks later. Respective inter- and intra-observer agreements were calculated in the standard fashion using the kappa statistic. Both inter- and intra-observer agreements were excellent (kappa= 0.77-0.85). The Adams grading system for discogram morphology is consistently reproducible amongst observers with differing levels of experience. It can be safely recommended in the clinical setting as a reliable classification.

Adult↗