ObjectivesNormal sagittal spine-pelvis-lower extremity alignment is crucial in humans for maintaining an ergonomic upright standing posture, and pathogenesis in any segment leads to poor balance. The present study aimed to investigate how this sagittal alignment can be affected by severe knee osteoarthritis (KOA), and whether associated changes corresponded with symptoms of lower back pain (LBP) in this patient population.MethodsLateral radiograph films in an upright standing position were obtained from 59 patients with severe KOA and 58 asymptomatic controls free from KOA. Sagittal alignment of the spine, pelvis, hip and proximal femur was quantified by measuring several radiographic parameters. Global balance was accessed according to the relative position of the C7 plumb line to the sacrum and femoral heads. The presence of chronic LBP was documented. Comparisons between the two groups were carried by independent samples t-tests or chi-squared test.ResultsPatients with severe KOA showed significant backward femoral inclination (FI), hip flexion, forward spinal inclination, and higher prevalence of global imbalance (27.1% versus 3.4%, p < 0.001) compared with controls. In addition, patients with FI of 10° (n = 23) showed reduced lumbar lordosis and significant forward spinal inclination compared with controls, whereas those with FI > 10° (n = 36) presented with significant pelvic anteversion and hip flexion. A total of 39 patients with KOA (66.1%) suffered from LBP. There was no significant difference in sagittal alignment between KOA patients with and without LBP.ConclusionsThe sagittal alignment of spine-pelvis-lower extremity axis was significantly influenced by severe KOA. The lumbar spine served as the primary source of compensation, while hip flexion and pelvic anteversion increased for further compensation. Changes in sagittal alignment may not be involved in the pathogenesis of LBP in this patient population.Cite this article: W. J. Wang, F. Liu, Y.W. Zhu, M.H. Sun, Y. Qiu, W. J. Weng. Sagittal alignment of the spine-pelvis-lower extremity axis in patients with severe knee osteoarthritis: A radiographic study. Bone Joint Res 2016;5:198–205. DOI:10.1302/2046-3758.55.2000538.

Background Gum chewing has been reported to enhance bowel motility and reduce postoperative ileus (POI). However, the efficacy remains imprecise for women following caesarean section.Objectives To summarise and evaluate the current evidence for postoperative gum chewing on the recovery of bowel function following caesarean section.Search strategy We searched studies from the following electronic databases: PubMed, EMBASE, SCOPUS and Cochrane Library from inception to 30 May 2013.Selection criteria We included randomised controlled trials (RCTs) of women after caesarean section; these RCTs should compared gum chewing with no gum chewing and reported on at least one of the outcomes: time to flatus, time to bowel sound, time to passing stool and length of hospital stay (LOS).Data collection and analysis Study outcomes were presented as mean differences (for continuous data) with 95% confidence interval (95% CI). The risk of bias in the study results was assessed using the assessment tool from the Cochrane Handbook.Main results Six RCTs including 939 women were included in our meta-analysis. The pooled results demonstrated that gum chewing is superior to no gum chewing with a reduction of 6.42 hours (95% CI À7.55 to À5.29) for time to first flatus, 3.62 hours (95% CI À6.41 to À0.83) for time to first bowel sound, 6.58 hours (95% CI À10.10 to À3.07) for time to first stool and 5.94 hours (95% CI À9.39 to À2.49) for LOS. In addition, no evidence emerged for any side effects caused by gum chewing.Conclusions The current evidence suggests that gum chewing is associated with early recovery of bowel motility and shorter LOS for women after caesarean section. This safe and inexpensive intervention should be included in routine postoperative care following a caesarean section.Keywords Caesarean section, gum chewing, ileus, meta-analysis, postoperative.Please cite this paper as: Zhu Y-P, Wang W-J, Zhang S-L, Dai B, Ye D-W. Effects of gum chewing on postoperative bowel motility after caesarean section: a meta-analysis of randomised controlled trials. BJOG 2014;121:787-792.