How well do we assess the adequacy of bending films in scoliosis?

Aims: To determine whether side-bending films in scoliosis are assessed for adequacy in clinical practice; and to introduce a novel method for doing so. Methods: Six surgeons and eight radiographers were invited to participate in four online surveys. The generic survey comprised erect and left and right bending radiographs of eight individuals with scoliosis, with an average age of 14.6 years. Respondents were asked to indicate whether each bending film was optimal (adequate) or suboptimal. In the first survey, they were also asked if they currently assessed the adequacy of bending films. A similar second survey was sent out two weeks later, using the same eight cases but in a different order. In the third survey, a guide for assessing bending film adequacy was attached along with the radiographs to introduce the novel T1-45B method, in which the upper endplate of T1 must tilt ≥ 45° from baseline for the study to be considered optimal. A fourth and final survey was subsequently conducted for confirmation. Results: Overall, 12 (86%) of 14 respondents did not use any criteria to assess the bending film adequacy; the remaining two each described a different invalidated method. In total, 12 (86%) of the respondents felt T1-45B was easy to learn and apply. There was fair to substantial intra-rater reliability (k = 0.25 to 0.88) which improved to fair to almost perfect (k = 0.38 to 0.88) post-introduction of the guide. Inter-rater reliability varied considerably among the rater groups but similarly increased following introduction of the guide (kS1 = 0.19 to 0.34, kS2 = 0.33 to 0.43 vs kS3 = 0.49 to 0.5, kS4 = 0.35 to 0.43). Conclusion: Many surgeons and radiographers do not assess spinal bending films for adequacy. We propose that the change in the plane of the upper endplate of T1 on side-bending can be used in this evaluation. In the T1-45B method, a change of ≥ 45° on side bending qualifies as an adequate bend effort.

Stereoscopic visual stimuli for examining biological motion perception and unanticipated steering manoeuvres in people with Parkinson's disease.

Community falls in people with Parkinson's disease (PwPD) are common, costly, and often unanticipated. Aside from static obstacles, it has been reported that oncoming people in community settings pose problems for PwPD when navigating. This suggests that PwPD may have difficulty (i) perceiving biological motion and action possibilities, and (ii) steering out of the way of oncoming persons. To date, laboratory research that investigated unanticipated steering manoeuvres in PwPD have only incorporated light- or arrow-based visual stimuli to simulate the spatiotemporal demands of these movements. However, such simple stimuli are not ecologically valid for examining biological motion perception and unanticipated steering manoeuvres used in avoiding oncoming people. To improve the generalisability of laboratory research in this field, a set of stereoscopic visual stimuli that feature an oncoming person initiating a sudden change in direction was developed for PwPD to engage with. Specifically, we modified and improved existing cinematographic techniques, software, and stereoscopic display technology to bring about:•Ambulatory scenarios that were quasi-immersed with the laboratory environment.•Enhanced realism.•Better temporal consistency in video playback.

Lessons learnt from an atypical mycobacterium infection post-anterior cruciate ligament reconstruction.

Infections following anterior cruciate ligament reconstruction are rare, with no previous reports citing Mycobacterium abscessus as the culprit pathogen. A 22-year-old man presented twice over three years with a painful discharging sinus over his right tibia tunnel site necessitating repeated arthroscopy and washout, months of antibiotic therapy, and ultimately culminating in the removal of the implants. In both instances, M. abscessus was present in the wound cultures, along with a coinfection of Staphyloccocus aureus during the second presentation. Though rare, M. abscessus is an important pathogen to consider in postoperative wounds presenting with chronic discharging sinuses, even in healthy non-immunocompromised patients. This case illustrates how the organism can cause an indolent infection, and how the removal of implants can be necessary to prevent the persistence of infection. Coinfection with a second organism is not uncommon and necessitates a timely change in treatment regime as well.

Lessons Learnt from an Atypical Mycobacterium Infection Post-Anterior Cruciate Ligament Reconstruction

Infections following anterior cruciate ligament reconstruction are rare, with no previous reports citing Mycobacterium abscessus as the culprit pathogen. A 22-year-old man presented twice over three years with a painful discharging sinus over his right tibia tunnel site necessitating repeated arthroscopy and washout, months of antibiotic therapy, and ultimately culminating in the removal of the implants. In both instances, M. abscessus was present in the wound cultures, along with a coinfection of Staphyloccocus aureus during the second presentation. Though rare, M. abscessus is an important pathogen to consider in postoperative wounds presenting with chronic discharging sinuses, even in healthy non-immunocompromised patients. This case illustrates how the organism can cause an indolent infection, and how the removal of implants can be necessary to prevent the persistence of infection. Coinfection with a second organism is not uncommon and necessitates a timely change in treatment regime as well.

Anterior lumbar interbody surgery for spondylosis results from a classically-trained neurosurgeon.

Anterior lumbar surgery for degenerative disc disease (DDD) is a relatively novel technique that can prevent damage to posterior osseous, muscular and ligamentous spinal elements. This study reports the outcomes and complications in 286 patients who underwent fusion - with artificial disc implants or combined fusion and artificial disc implants - by a single-operator neurosurgeon, with up to 24 months of follow-up. The visual analogue scale (VAS), Oswestry Disability Index (ODI), Short Form 36 (SF36) and prospective log of adverse events were used to assess the clinical outcome. Radiographic assessments of implant position and bony fusion were analysed. Intraoperative and postoperative complications were also recorded. Irrespective of pre-surgical symptoms (back pain alone or back and leg pain combined), workers' compensation status and type of surgical implant, clinically significant improvements in VAS, ODI and SF36 were primarily observed at 3 and/or 6 month follow-up, and improvements were maintained at 24 months after surgery. A 94% fusion rate was obtained; the overall complication was 9.8% which included 3.5% with vascular complications. The anterior lumbar approach can be used for treating DDD for both back pain and back and leg pain with low complication rates. With appropriate training, single-operator neurosurgeons can safely perform these surgeries.

Infusion-line pressure as a real-time monitor of convection-enhanced delivery in pre-clinical models.

BACKGROUND: Acute convection-enhanced delivery (CED) is a neurosurgical delivery technique that allows for precise and uniform distribution of an infusate to a brain structure. It remains experimental due to difficulties in ensuring successful delivery. Real-time monitoring is able to provide immediate feedback on cannula placement, infusate distribution, and if the infusion is proceeding as planned or is failing due to reflux or catheter obstruction. NEW METHOD: Pressure gradient is the driving force behind CED, with the infusion pressure being directly proportional to the flow-rate. The aim of this study was to assess the feasibility of using infusion-line pressure profiling to distinguish in real-time between succeeding and failing CED infusions. To do so we delivered cresyl violet dye at 0.5, 1.0 and 2.0 µl/min via CED in vitro using 0.6% agarose gel and in vivo to the rat striatum. RESULTS: Infusions that failed in agarose gel models could only be differentiated late during the procedures. In the rat in vivo model, the infusion-line profiles of obstructed infusions were not distinctive from those of successful infusions. COMPARISON WITH EXISTING METHOD: Intraoperative magnetic resonance imaging (MRI) is used for real-time visualisation of cannula placement and infusate distribution. Particularly for animal pre-clinical work, it would be advantageous to supplement MRI with a cheap, accessible technique to monitor infusions and provide a real-time measure of infusion success or failure. CONCLUSIONS: Infusion-line pressure monitoring was of limited value in identifying successful CED with small volume infusions, whilst its utility for large volume infusion remains unknown.

Relative influence of prey mercury concentration, prey energy density and predator sex on sport fish mercury concentrations.

Mercury (Hg) bioaccumulation in aquatic food webs has created a human health concern for anglers who consume fish. Variability in sport fish Hg concentration adds to the uncertainty of the amount of fish an angler can safely consume, so predicting where variability arises is useful. We evaluated the relative influence of diet (prey Hg concentration and energy density) and sex on sport fish Hg concentrations using a bioenergetics approach. Our results indicated that sport fish diets (prey Hg concentration followed by energy density) were the most important factors for determining sport fish Hg concentration followed by sex. Although physiological and behavioral differences based on sex may lead to differences in gross growth efficiency, resulting in different Hg concentrations in male and female sport fish, evaluating the relative importance of these differences will require sex-specific parameterization of bioenergetics models. Our results support previous findings that knowledge of sport fish diets (prey Hg concentration followed by energy density) and sex could aid in the prediction of sport fish Hg concentrations. Thus, basic knowledge of system-specific food web structure could provide valuable information for developing sport fish consumption advisories to better protect anglers and their families from Hg contamination.