Aim. To systematically review the literature and anatomical atlases on LM morphology. Methods. Relevant studies were searched in PubMed (Medline) and Science Direct. Anatomical atlases were retrieved from multiple university libraries and online. Included atlases and studies were assessed at five items: visuals present(y/n), quality of visuals(in-/sufficient), labelling of multifidus (y/n), clear description of region of interest(y/n), description of plane has been described(y/n). This risk of bias assessment tool was developed to assess the quality of description of anatomy, since existing risk of bias tables have only been developed to assess the methodology of studies. Results. In total 69 studies and 19 anatomical atlases were included. Studies. - 52 of 69 studies, LM was described as a superficial muscle at the levels L4 – S1. Others presented the LM as deep intrinsic muscle. - Most used methods: MRI, ultrasound imaging or drawings. - 32 of 69 studies scored a total of five points at the risk of bias assessment, which means low risk of bias. Anatomical atlases. - LM is shown as a deep intrinsic back muscle covered by the erector spinae and fascia thoracolumbalis. - Most anatomical atlases (8/19) had a score of four points at the risk of bias assessment. Conclusion. Anatomy atlases reported different LM morphology compared to anatomical studies. Even between studies, there appears to be inconsistent reporting in LM anatomy. Variation in research methods that are used for measuring LM morphology could influence variation in describing and presenting LM morphology. Standardization of research methodology is recommended in order to compare studies. No conflicts of interest. Sources of Funding: SIA RAAK-Publiek

Background. Several theories have been put forward with respect to the mechanical role of the thoracolumbar fascia (TLF) but none have been substantiated in part due to an inability to explore its function in vivo. This study explored the use of ultrasound to image the layers of the TLF in vivo. Methods. Initially a cadaveric dissection of the fascia was performed to gain an appreciation of the 3-D orientation and representation of the TLF in the lumbar region. A conventional ultrasound system (Diasus, Dynamic Imaging Ltd) was then used to image the 3 layers of the fascia on 40 normal subjects (18 males and 22 females, mean age 27.3±5.8 years) and the reliability of these measures was investigated on a subset of this population. Results. Using ultrasound, the posterior and middle layer of the TLF could be readily identified, however it was not possible to visualise the anterior layer due to the limitations of the scanner used. The thickness of the posterior layer ranged from 1.3 ±0.4 to 1.5±0.4 mm depending on location relative to the spinous process. The middle layer tended to be thinner being 1.0±0.4mm on average. Intra-observer errors were within acceptable ranges, although not ideal. Conclusion. Ultrasound may be an important tool for understanding the mechanical role of fascia, however this would necessitate the use of high resolution scanner to enhance the reliability of images. Further work is required to image changes in the presentation of fascia in different loaded functional positions

Aims

We present a case series of five patients who had revision surgery following magnetic controlled growing rods (MGCR) for early onset scoliosis. Metallosis was found during revision in four out of five patients and we postulated a mechanism for rod failure based on retrieval analysis.