Vitamin D Deficiency and Outcomes After Ankle Fusion: A Short Report

Background: Vitamin D deficiency has been postulated as a cause for impaired bone healing and remodeling. The purpose of this study was to assess the potential association between low vitamin D levels and reoperation for nonunion following ankle fusion surgery. Methods: All adult patients (aged ≥18 years) who underwent ankle fusion procedures at a tertiary referral center from January 2010 to January 2019 with available vitamin D levels within 12 months preoperatively were retrospectively reviewed (n = 47). Patients were categorized as vitamin D deficient (<30 ng/mL) vs normal (31-80 ng/mL). The primary outcome was the incidence of reoperation secondary to nonunion. Secondary outcomes included incidence of reoperation not related to nonunion and the need for repeat reoperation. Results: The average level in the vitamin D–deficient group (n = 17; 36.2%) was 16.9 vs 46.4 ng/mL in the normal group (n = 30; 63.8%). All recorded reoperations for nonunion occurred exclusively in the vitamin D–deficient cohort (4/17 [23.5%]; P = .013). There were similar reoperation rates for causes other than nonunion (2/17 [11.8%] vs 4/30 [13.3%]; P > .99) and repeat reoperation rates (3/17 [17.6%] vs 1/30 [3.3%]; P = .128) among vitamin D–deficient vs normal patients. Conclusion: Vitamin D deficiency may be associated with an increased risk of reoperation for nonunion after ankle fusion.

Repeated Ct-based Hounsfield Unit Measurements as a Proxy Measure of Intercorporal Bone Graft Remodelling Towards Spinal Fusion; a Feasibility Study.

Background: There is a lack of knowledge about the biological process of intercorporal bone graft remodelling towards successful lumbar spine fusion with bridging vital bone between two adjacent vertebrae. Hounsfield Units (HU) highly correlate with Bone Mineral Density (BMD) and changes in HU may be valuable as proxy measure to monitor ongoing fusion. The aims of this study were to explore the feasibility to quantify BMD changes in the intercorporal bone graft after spinal fusion on consecutive CT-scans, and to explore whether trends in the individual changes in HU over time may serve as a proxy measure for successful fusion or non-fusion.Methods: A retrospective case series was conducted using available one-year and two-year CT-data from patients after posterior lumbar interbody fusion surgery. First, a standardized measuring procedure was developed, incorporating internal phantomless calibration, to establish the HU values of the grafted region of interest using consecutive CT-slices. Subsequently, changes in the participants’ bone graft HU over time between their first and second year after surgery were explored.Results: Between one and two years after surgery, seven out of nine (78%) participants showed an increase in their bone grafts’ HU, ranging from 3% to 41%. In two participants HU-values decreased 14% and 32%, respectively. The intraobserver reliability of the HU measuring procedure was excellent (ICC 0.93 (95% confidence interval 0.91 to 0.95)).Conclusion: The majority (78%) of participants in the current study showed increases in their bone graft HU, which suggests ongoing bone graft remodelling towards lumbar fusion. This result corresponds with the established percentages of achieved rigid bony fusion after lumbar spinal fusion surgery reported in the literature. Thus, prospective follow-up of CT-based HU measurements may have potential as diagnostic measure to monitor bone graft remodelling in time and trends may predict successful fusion or non-fusion. The measurement procedure developed in this study, using internal phantomless calibration, showed excellent intraobserver reliability and merits further study in larger patient numbers.

Process Evaluation of Lumbar Interbody Fusion Surgeries in Five Dutch Hospitals: A Qualitative Analysis

Background and Objectives: Only limited qualitative research concerning instrumented spine surgeries has been published, despite the increasing number of these surgeries and the evident importance of qualitative analysis of the processes surrounding these complex interventions. Current qualitative research is mainly limited to the experiences, emotions and expectations of patients. Insight into the full process, including experiences from the perspective of informal caregivers and healthcare professionals, remains scarce. Materials and Methods: Data were gathered by means of semi-structured face-to-face interviews. In total, there were 27 participants, including 11 patients, 7 informal caregivers and 9 healthcare professionals. The interview process was audiotaped, and each interview was transcribed verbatim. To systematically analyse the gathered data, software for qualitative analysis (NVivo) was used. After immersion in the raw data of transcripts and field notes, a list of broad categories for organising the data into meaningful clusters for analysis was developed. All interviews were coded by the first author, and 25% was independently assessed by the second author. Results: The results of our study describe several promoting and limiting factors concerning the process of lumbar fusion surgery from the perspective of patients, informal caregivers and healthcare providers. The most frequently mentioned promoting factors were: information and opportunities to ask questions during consultations; multidisciplinary consultations; good communication and guidance during hospitalization; and follow-up appointments. The most frequently mentioned limiting factors were: lack of educational material; lack of guidance and communication prior to, during and after hospitalisation. Conclusion: Overall, participants were satisfied with the current healthcare-process in lumbar fusion surgery. However, we found that lack of educational material and guidance during the process led to insecurity about complaints, surgery and recovery. To improve the process of lumbar interbody fusion and to increase patient satisfaction, healthcare providers should focus on guiding and educating patients and informal caregivers about the pre-operative trajectory, the surgery and the recovery. From the healthcare providers’ perspective, the process could be improved by multidisciplinary consultations and a dedicated spine team in the operation room. Although this study focusses on lumbar fusion surgery, results could be translated to other fields of spine surgery and surgery in general.

Approach-related anatomical differences in patients with lumbo-sacral transitional vertebrae undergoing lumbar fusion surgery at level L4/5

Introduction Lumbo-sacral transitional vertebrae (LSTV) are accompanied by changes in soft tissue anatomy. The aim of our retrospective study was to evaluate the effects of LSTV as well as the number of free lumbar vertebrae on surgical approaches of ALIF, OLIF and LLIF at level L4/5. Material and methods We assessed the CTs of 819 patients. Of these, 53 had LSTV from which 11 had six (6LV) and 9 four free lumbar vertebrae (4LV). We matched them for sex and age to a control group. Results Patients with LSTV had a higher iliac crest and vena cava bifurcation, a greater distance between the common iliac veins and an anterior translation of the psoas muscle at level L4/5. In contrast, patients with 6LV had a lower iliac crest and aortic bifurcation, no differences in vena cava bifurcation and distance between the iliac veins compared to the control group. Conclusions For patients with LSTV and five or four free lumbar vertebrae, the LLIF approach at L4/5 may be hindered due to a high riding iliac crest as well as anterior shift of the psoas muscle. Whereas less mobilization and retraction of the iliac veins may reduce the risk of vascular injury at this segment by ALIF and OLIF. For patients with 6LV, a lower relative height of the iliac crest facilitates lateral approach during LLIF. For ALIF and OLIF, a stronger vessel retraction due to the deeper-seated vascular bifurcation is necessary during ALIF and is therefore potentially at higher risk for vascular injury.

Regional variations in lumbar spine surgery in Finland

Introduction The regional variation in spine surgery rates has been shown to be large both within and between countries. This variation has been reported to be less in studies from countries with spine registers. The aim of this study was to describe the regional variation in lumbar spine surgery in Finland. Materials and methods This is a retrospective register study. Data from the Finnish National Hospital Discharge Register (NHDR) were used to calculate and compare the rates of lumbar disc herniation (LDH), decompression, and fusion surgeries in five University Hospital catchment areas, covering the whole Finnish population, from January 1, 1997, through December 31, 2018. Results A total of 138,119 lumbar spine operations (including LDH, decompression, and fusion surgery) were performed in Finland between 1997 and 2018. The regional differences in the rate of LDH surgery were over fourfold (18 vs. 85 per 100,000 person years), lumbar decompression surgery over threefold (41 vs. 129 per 100,000 person years), and lumbar fusion surgery over twofold (14 vs. 34 per 100,000 person years) in 2018. The mean age of the patients increased in all regions during the study period. Conclusions In Finland, the regional variations in spine surgeries were vast. In a country with a publicly funded healthcare system, this finding was surprising. The recently created national spine register may serve to shed more light on the reasons for this regional variation.

Fatal Pulmonary Fat Embolism Occurring in Lumbar Spinal Fusion Surgery: Case Report and Review of Literature

Fat embolism system is one of the serious complications of orthopedic surgery, which is common seen in cases of severe trauma with long bone fractures. However, in clinical medical practice, it is rarely seen for Fat embolism system in orthopaedic lumbar fusion surgery. This paper report a case of sudden shock and death during lumbar fusion due to lumbar intervertebral disc disease. By forensic pathological examination, the pulmonary and brain fat embolism were observed in tissue sections, and the patient was diagnosed as FES. Based on the review of relevant literature and the pathological findings of this case, the clinical characteristics, diagnosis and treatment of FES in lumbar fusion are commentated in this paper. At the same time, it is emphasized that the clinical practise should strengthened the understanding and attention of non-traumatic fat embolism cases in order to timely identify, diagnose and treat the disease, improve the effectiveness of treatment, and reduce the corresponding medical disputes.