Prevalence and characteristics of lumbar ribs: a meta-analysis with anatomical and clinical considerations.

BACKGROUND: Lumbar ribs (LR) are a rare and relatively unknown anatomical abnormality of the lumbar spine. The literature provides better understanding regarding other spinal congenital variations like cervical ribs or lumbosacral transitional vertebrae, which are rather commonly recognised conditions. Thus, this meta-analysis aimed to provide data on prevalence and key characteristics of LR. METHODS: Relevant databases were systematically searched for studies reporting the prevalence, laterality and geographic distribution of LR. No exclusion criteria based on language and date of original articles were employed. The pooled prevalence estimates (PPE) were calculated using a random-effects model. To assess the between-study heterogeneity, the I2 statistic and Chi-square test were utilized. Throughout the investigation, the PRISMA guidelines were adhered to scrupulously. Evaluation of the included studies' reliability was made with the AQUA tool. RESULTS: In total, 9 studies were included in this meta-analysis. The pooled prevalence estimate (PPE) of LR was 2.1% (95%CI: 1.0-4.6). In studies based on CT imaging, LR were found in 1.6% (95%CI: 0.6-4.3) of patients and in Xray based studies in 2.1% (95%CI: 0.4-11.1) of patients. Lumbar ribs were bilateral in majority of individuals (65.4%, 95%CI: 39.4-84.6) and could be most frequently encountered in Europe with PPE of 2.8% (95%CI: 3.0-20.0), then in East Asia with PPE of 1.5% (95%CI: 1.0-19.2) and Middle East with PPE of 1.1% (95%CI: 0.6-20.0). CONCLUSIONS: The findings of our study indicate that LR are a common anatomical variation of lumbar spine, contrary to previous beliefs. In a clinical practice, when a patient presents with a non-specific low back pain, a possible occurrence of LR should be taken into consideration. The presence of LR may be misleading for surgeons and result in wrong-level spine surgeries.

A Case of Granulicatella adiacens Osteomyelitis and Mitral Valve Endocarditis.

Granulicatella adiacens is a nutritionally variant streptococci (NVS) that can cause various infections, including but not limited to endocarditis, osteomyelitis, pneumonia, and abscess. We report a case of an 80-year-old male who was found to have Granulicatella adiacens osteomyelitis and mitral valve endocarditis. Also included is a systematic review of osteomyelitis caused by Granulicatella adiacens.

Alignment in motion: Fall risk in spine patients and the effect of vision, support surface, and adaptation on the cone of economy.

Background: Several assessment tools have been developed to estimate a patient's likelihood risk of falling. None of these measures estimate the contributions of the visual, vestibular, and somatosensory systems to fall risk, especially in patients with degenerative lumbar spine disease. Methods: Degenerative lumbar spine patients with radiculopathy (LD) and healthy subjects who were 35-70 years old without spine complaints were recruited. Patient reported outcome measures (PROMs) were collected prior to testing. Fall risk assessment was completed using Computer Dynamic Posturography (CDP), a computer-controlled balance machine that allows cone of economy (CoE) and cone of pressure (CoP) measurements. All patients completed Sensory Organization Tests (SOT) which include normal and perturbed stability, both with and without visual cues. Results: In total, 43 spine patients and 12 healthy controls were included, with mean age 57.8 years, 39.5% females, and mean BMI of 29.3 kg/m2. Nearly all CoE and most CoP dimensions were found to be larger in LD patients compared to controls across nearly all subtests (p<.05), with the largest dimensions generally observed in the surrounding and support sway testing condition. In LD patients, ODI and PROMIS Pain Interference were negatively correlated with CoE and CoP measurements (p<.05). Conclusions: In this prospective study, body sway was assessed as a function of CoE and CoP using the CDP system and was found to be elevated in spine patients, especially when they experienced increasing levels of visual and vestibular stimulation. The ability to identify the primary drivers of balance disorders is essential in spine patients and may be helpful in the development of a patient-specific treatment plan, which may in the future aid with fall-prevention initiatives.

Risk Factors for Nonunion After Nonoperative Treatment for Pediatric Lumbar Spondylolysis: A Retrospective Case-Control Study.

BACKGROUND: Pediatric lumbar spondylolysis, a stress fracture of the lumbar spine, frequently affects young athletes, and nonoperative treatment is often the first choice of management. Because the union rate in lumbar spondylolysis is lower than that in general fatigue fractures, identifying risk factors for nonunion is essential for optimizing treatment. PURPOSE: To determine the risk factors for nonunion after nonoperative treatment of acute pediatric lumbar spondylolysis through multivariate analysis. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: We analyzed 574 pediatric patients (mean age, 14.3 ± 1.9 years) with lumbar spondylolysis who underwent nonoperative treatment between 2015 and 2022. Nonoperative treatment included the elimination of sports activities, bracing, and weekly athletic rehabilitation, with follow-up computed tomography. Patient data, lesion characteristics, sports history, presence of spina bifida occulta at the lamina with a lesion or at the lumbosacral spine excluding the lesion level, and lumbosacral parameters were examined. Differences between the union and nonunion groups were investigated using multivariate analysis to determine the risk factors for nonunion. RESULTS: Of the 574 patients, 81.7% achieved bone union. Multivariate analysis revealed that an L5 lesion and the progression of the main and contralateral lesion stages were significant independent risk factors for nonunion. An L5 lesion had a lower union rate than non-L5 lesions. As the main lesion progressed, the likelihood of nonunion increased significantly, and the progression of the contralateral lesion also showed a similar trend. Spina bifida occulta and lumbosacral parameters were not significant predictors of nonunion in this study. CONCLUSION: We identified the L5 lesion level and the progression of the main and contralateral lesion stages as independent risk factors for nonunion in pediatric lumbar spondylolysis after nonoperative treatment. These findings aid in treatment decision-making. When bone union cannot be expected with nonoperative treatment, symptomatic treatment is required without prolonged external fixation and rest, and without aiming for bone union. Individualized treatment plans are crucial based on identified risk factors.

Ultrashort-Echo-Time MRI of the Disco-Vertebral Junction: Modulation of Image Contrast via Echo Subtraction and Echo Times.

INTRODUCTION: The disco-vertebral junction (DVJ) of the lumbar spine contains thin structures with short T2 values, including the cartilaginous endplate (CEP) sandwiched between the bony vertebral endplate (VEP) and the nucleus pulposus (NP). We previously demonstrated that ultrashort-echo-time (UTE) MRI, compared to conventional MRI, is able to depict the tissues at the DVJ with improved contrast. In this study, we sought to further optimize UTE MRI by characterizing the contrast-to-noise ratio (CNR) of these tissues when either single echo or echo subtraction images are used and with varying echo times (TEs). METHODS: In four cadaveric lumbar spines, we acquired 3D Cones (a UTE sequence) images at varying TEs from 0.032 ms to 16 ms. Additionally, spin echo T1- and T2-weighted images were acquired. The CNRs of CEP-NP and CEP-VEP were measured in all source images and 3D Cones echo subtraction images. RESULTS: In the spin echo images, it was challenging to distinguish the CEP from the VEP, as both had low signal intensity. However, the 3D Cones source images at the shortest TE of 0.032 ms provided an excellent contrast between the CEP and the VEP. As the TE increased, the contrast decreased in the source images. In contrast, the 3D Cones echo subtraction images showed increasing CNR values as the second TE increased, reaching statistical significance when the second TE was above 10 ms (p < 0.05). CONCLUSIONS: Our study highlights the feasibility of incorporating UTE MRI for the evaluation of the DVJ and its advantages over conventional spin echo sequences for improving the contrast between the CEP and adjacent tissues. Additionally, modulation of the contrast for the target tissues can be achieved using either source images or subtraction images, as well as by varying the echo times.

Discitis Mimicking Septic Arthritis in a 17-Month-Old Boy.

Discitis in children is uncommon, typically occurring between the ages of two and eight years. The etiology is not established, but it is generally considered a bacterial infection. Symptoms vary with age but commonly include irritability, refusal to walk, and back pain. These various clinical presentations cause delays in diagnosis. We present this case to draw attention and familiarise clinicians with its presentations. A 17-month-old boy presented with a one-week history of refusal to walk. Examination showed an unusual finding of the child keeping his right leg in a flexed position with hip tenderness. Inflammatory markers were raised. Initially, the patient was managed for suspected septic arthritis of the hip joint. Initial tests were inconclusive, and magnetic resonance imaging (MRI) on day 23 revealed discitis at L4-L5. After a course of antibiotics and monitoring of inflammatory markers, his clinical condition improved. The mainstay of treatment is antibiotics, with surgery reserved for complicated cases. Discitis has a good prognosis in children.

Ossified spinal epidermoid cyst: A systematic review and case report.

Background: Epidermoid cysts (ECs) are rare, benign lesions which comprise less than 1 % of all spinal tumors. Calcification of spinal ECs is rare, and EC ossification within the lumbar spine has never been documented. We report the only known congenital lumbar epidermoid tumor with ossification and a literature review of intradural lumbar ECs. Methods: Studies meeting the following criteria were included: 1) EC as the primary tumor type, 2) intradural location, 3) involvement of the lumbar spinal level, and 4) primary presentation. Studies lacking individual patient data or published in a non-English language were excluded. Results: A total of 172 studies were reviewed and 43 were included in analysis. Of the 83 total patients, 37 (45.1 %) were male and 45 (54.9 %) female, at an average age of 26 years. The L3 and L4 spinal levels were most frequently involved. Acquired etiology was reported in 49 (59.0 %) patients, and 24 (28.9 %) cases were congenital. Multivariate analyses demonstrated trends between decreased age and improved outcome, decreased delay in diagnosis and improved outcome, and increased extent of resection with reduced recurrence. Nine calcified spinal ECs were identified, with no previous report of EC ossification in the lumbar spine. Conclusion: We present a case report of the only known ossified epidermoid tumor of the lumbar spine and a comprehensive literature review of 83 patients with intradural lumbar ECs. This review demonstrated trends between reduced age and improved outcome, reduced delay in diagnosis and improved outcome, and increased extent of resection with reduced recurrence.

Revisiting abdominal wall "morbidity" of the extensile anterolateral approach to the thoracolumbar spine.

PURPOSE: To assess patients' perceptions of their abdominal wall following extensile anterolateral approaches to the thoracolumbar spine for adult spinal deformity (ASD) using validated questionnaires. METHODS: Adults who underwent anterior-posterior thoracolumbar spinal operations to the pelvis for ASD in which the anterior fusion was performed through an extensile anterolateral approach were reviewed. Three questionnaires were administered at least 1 year following surgery and included The Abdominal Core Health Quality Collaborative Survey (AHS-QC), The Patient Scar Assessment Scale (PSAS), and The Anterior Abdominal Incision Questionnaire (AAIQ). RESULTS: Fifty-one patients (80.4% female, median age 65 years) were included. Average follow-up was 2.8 ± 1.7 years. Average number of anterior fusion levels was 3.5 ± 1.4. Patients achieved high satisfaction rates from surgery (74.5%). AAIQ responses included postoperative pain (33.3%), bulging (41.7%), and limitations in daily activities (18.8%) with only 15.7% experienced moderate-severe pain related to their incisions and only 6.3% seeking treatment for their scars. Post-operatively, 63.2% had a neutral or improved self-image of their torso and trunk, while only 10.2% stating it was much worse. Patients' overall opinion of their scar compared to their normal skin was very positive [average 2.75 ± 2.93 (10 = worst possible scar)]. Favorable scores were also reported for color difference, stiffness, change in thickness, and irregularity in their abdominal scar compared to normal skin. CONCLUSIONS: Following extensile anterolateral approaches to the thoracolumbar spine for ASD, the majority of patients reported mild pain, mild functional limitations, good cosmesis, and high satisfaction rates with their anterior incisions based on validated questionnaires.

Biomechanical modelling of indirect decompression in oblique lumbar intervertebral fusions - A finite element study.

BACKGROUND: Oblique lumbar intervertebral fusion aims to decompress spinal nerves via an interbody fusion cage, but the optimal surgical strategy, including implant selection for specific patient characteristics, remains unclear. A biomechanical model was developed to assess how pathophysiological characteristics and instrumentation impact spinal realignment, indirect decompression, and cage subsidence risk. METHODS: A finite element model of the L4-L5 segment was derived from a validated asymptomatic T1-S1 spine model. Five cases of grade I spondylolisthesis with normal or osteoporotic bone densities and initial disc heights of 4.3 to 8.3 mm were simulated. Oblique lumbar intervertebral fusion with cage heights of 10, 12, and 14 mm (12° lordosis) was examined. Postoperative changes in disc height, foraminal and spinal canal dimensions, segmental lordosis, and vertebral slip were assessed. Vertebral stresses and displacements under 10 Nm flexion and 400 N gravitational load were compared between stand-alone constructs and bilateral pedicle screw fixation using rods of 4.75, 5.5, and 6 mm diameters. FINDINGS: Oblique lumbar intervertebral fusion significantly improved postoperative disc height, foraminal and spinal canal dimensions, with the greatest enhancements observed with 14 mm cages. Bilateral pedicle screw fixation markedly reduced cortical endplate stresses and displacements compared to stand-alone constructs, with added benefits from larger rod diameters. Low bone density increased displacements by 63 %. INTERPRETATION: Thicker cages achieve better decompression but increase subsidence risk. Bilateral pedicle screw fixation with 6 mm rods minimizes endplate stresses and displacements, especially in osteoporotic cases. Future research will validate these findings and explore the model's potential for surgical planning.

The Influence of Wait Time on Surgical Outcomes in Elective Lumbar Degenerative Spine Conditions: A Retrospective Multicentre Cohort Study.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The impact of delayed access to operative treatment on patient reported outcomes (PROs) for lumbar degenerative conditions remains unclear. The goal of this study is to evaluate the association between wait times for elective lumbar spine surgery and post-operative PROs. METHODS: This study is a retrospective analysis of patients surgically treated for a degenerative lumbar conditions. Wait times were calculated from primary care referral to surgery, termed the cumulative wait time (CWT). CWT benchmarks were created at 3, 6 and 12 months. A multivariable logistic regression model was used to measure the associations between CWT and meeting the minimally clinically important difference (MCID) for the Oswestry Disability Index (ODI) score at 12 months post-operatively. RESULTS: A total of 2281 patients were included in the study cohort. The average age was 59.4 years (SD 14.8). The median CWT was 43.1 weeks (IQR 17.8 - 60.6) and only 30.9% had treatment within 6 months. Patients were more likely achieve the MCID for the ODI at 12 months post-operatively if they had surgery within 6 months of referral from primary care (OR 1.22; 95% CI 1.11 - 1.34). This relationship was also found at a benchmark CWT time of 3 months (OR 1.33; 95% CI 1.15 - 1.54) though not at 12 months (OR 1.08; 95% CI 0.97 - 1.20). CONCLUSIONS: Patients who received operative treatment within a 3- and 6-month benchmark between referral and surgery were more likely to experience noticeable improvement in post-operative function.

Origin of median sacral artery with fourth pair of lumbar artery - an alert for spine surgeons and interventionalists: A case report and mini literature review.

The median sacral artery (MSA) is the single unpaired dorsal branch of the abdominal aorta. The present case describes the relatively unusual origin of the median sacral artery in common with the fourth pair of lumbar arteries via a common trunk in a 74-year-old males' cadaver. Unusual common trunk is prone for iatrogenic injury in surgeries of the lumbar and pelvic region. Owing to the deep seated nature of MSA close to the periosteum of lumbar vertebrae and sacrum, detection of accidental rupture of MSA and ligation thereof becomes a difficult task. MSA is also increasingly being utilized for intra-arterial embolization of pelvic tumours. The proximal portion of the common origin may at times undergo cone shaped dilatation which is referred to as infundibulum or infundibular dilatation and can also transform into aneurysm later. Knowledge of this variation is imperative for spine and pelvic surgeons to avoid unwanted complications.

Cerebrospinal fluid protein concentration in patients with lumbar spinal stenosis.

Background: In this study, we examined the impact and degree of lumbar stenosis on cerebrospinal fluid (CSF) protein concentration. Methods: In this retrospective study, we analyzed protein concentrations in CSF samples of 61 patients with lumbar spinal stenosis (LSS) obtained during pre-operative myelography. Patients were divided into two groups: those showing no block to contrast (Group A) versus those showing medium block to contrast below the lumbar puncture level (Group B). Results: The CSF protein concentration in Group B (104.3 ± 59 g/dL) patients with medium block was significantly greater than that in Group A (65.1 ± 33 g/dL) patients without medium block. Conclusion: A higher average CSF protein concentration was seen in Group B patients with significant lumbar stenosis versus Group A patients without significant lumbar stenosis. Theoretically, damage to the cauda equina in patients with LSS may cause these elevated CSF protein levels.

Walking stress-induced changes in gait patterns and muscle activity: Patients with lumbar spinal stenosis versus asymptomatic controls.

INTRODUCTION: Patients with symptomatic lumbar spinal stenosis (sLSS) are often limited in their walking range because of worsening symptoms, which is thought to induce changes in the gait pattern. The aim of this study was to determine whether changes in gait pattern and muscle activity in these patients are elicited by a walking stress and differ from asymptomatic controls. METHODS: Twenty patients with sLSS and 19 asymptomatic controls performed a 30-minute walking stress. Gait was assessed using seven inertial sensors and sagittal joint range of motion (ROM) was calculated during different phases of gait. Muscle activation of the gluteus medius, erector spinae and multifidus muscles was measured by surface electromyography (EMG) and integrated EMGs (normalized to the maximum during gait) were calculated. Differences between groups and time points (beginning and end) were assessed using mixed factorial analysis of variance. RESULTS: Patients had less knee extension ROM in terminal stance, less knee flexion ROM in swing and less overall hip flexion/extension ROM than controls (p ≤ 0.03). There were no functionally relevant changes in these parameters during the walking stress. The integrated EMG was greater in all muscles in patients than in controls and increased in both groups during the walking stress in the paraspinal but not in the gluteus medius muscle. There was no interaction between group and time for any of the parameters. CONCLUSION: Differences in gait pattern and muscle activity between patients with sLSS and controls are generally present, but are not amplified by a walking stress.

Segmental vertebral three-dimensional motion in patients with L4 isthmic spondylolisthesis under weight-bearing conditions.

OBJECTIVE: To investigate in vivo 6-degree-of-freedom (DOF) vertebral motion in patients with isthmic spondylolisthesis (IS) during various functional weight-bearing activities. METHODS: Fifteen asymptomatic volunteers (mean age 54.8 years) and fourteen patients with IS at L4-5 (mean age 53.4 years) were recruited. The positions of the vertebrae (L4-L5) in the supine, standing, flexion-extension, left-right twisting and left-right bending positions were determined using previously described CT-based models and dual fluoroscopic imaging techniques. Local coordinate systems were established at the center of the anterior vertebra of L4 isthmic spondylolisthesis (AIS), the posterior lamina of L4 isthmic spondylolisthesis (PIS) and the center of the L5 vertebra to obtain the 6DOF range of motion (ROM) at L4-L5 and the range of motion (ROM) between the AIS and the PIS. RESULTS: The translation along the anteroposterior axis at L4-L5 during flexion-extension, left-right bending and left-right twisting was significantly greater than that of the healthy participants. However, the translation along the mediolateral axis at L4-L5 presented paradoxical motion under different positions: the ROM increased in the supine-standing and flexion-extension positions but decreased in the left-right bending and left-right twisting positions. The separation along the anteroposterior axis during flexion was significantly greater than that during standing, on average, reaching more than 1 mm. The separation along the mediolateral axis during standing, flexion and extension was significantly greater than that in the supine position. CONCLUSIONS: This study revealed the occurrence of displacement between the AIS and PIS, primarily in the form of separation during flexion. Symptomatic patients with isthmic spondylolisthesis exhibit intervertebral instability, which might be underestimated by flexion-extension radiographs.

Assessment of age-dependent sexual dimorphism in paediatric vertebral size and density using a statistical shape and statistical appearance modelling approach.

This work focuses on the growth patterns of the human fourth lumbar vertebra (L4) in a paediatric population, with specific attention to sexual dimorphism. The study aims to understand morphological and density changes in the vertebrae through age-dependent statistical shape and statistical appearance models, which can describe full three-dimensional anatomy. Results show that the main growth patterns are associated with isotropic volumetric vertebral growth, a decrease in the relative size of the vertebral foramen, and an increase in the length of the transverse processes. Moreover, significant sexual dimorphism was demonstrated during puberty. We observe significant age and sex interaction in the anterior vertebral body height (P = 0.005), where females exhibited an earlier increase in rates of vertebral height evolution. Moreover, we also observe an increase in cross-sectional area (CSA) with age (P = 0.020), where the CSA is smaller in females than in males (significant sex effect P = 0.042). Finally, although no significant increase in trabecular bone density with age is observed (P = 0.363), a trend in the statistical appearance model suggests an increase in density with age.

Mindfulness vs. Physiotherapy vs. Medical Therapy: Uncovering the Best Postoperative Recovery Method for Low Back Surgery Patients during the COVID-19 Pandemic-A Single Institution's Experience.

INTRODUCTION: This study aimed to evaluate the efficacy of mindfulness therapy compared to traditional physiotherapy and usual care in alleviating postoperative pain and improving functional outcomes in patients undergoing lumbar spine surgery during the COVID-19 pandemic. METHODS: Ninety patients undergoing lumbar decompression and fusion (LDF) who presented persistent low back pain after surgery were prospectively followed for one year. They were randomly divided into three groups: mindfulness therapy, physiotherapy, and medical therapy. The primary outcome was the improvement of the Oswestry Disability Index (ODI) score postoperatively and at six months follow-up. RESULTS: Both mindfulness and physiotherapy groups showed significant improvement in ODI scores compared to the control group, with mean variations of 10.6 and 11.6 points, respectively, versus 4.9 points in the control group. There was no significant difference between mindfulness and physiotherapy (p = 0.52), but both were superior to medical care (p < 0.0001 for physiotherapy and p = 0.0007 for mindfulness). CONCLUSIONS: This study demonstrated that mindfulness therapy is more effective than usual care in improving postoperative outcomes for patients undergoing lumbar spine surgery. In our cohort, its efficacy was comparable to that of physiotherapy, making it a viable alternative, especially when access to healthcare services is restricted, as seen during the COVID-19 pandemic. Future research should validate the findings of this study and examine the long-term effects on surgical patient populations.

Ultrasound assisted versus landmark based intrathecal administration of nusinersen in adults with spinal muscular atrophy disease: A randomized trial.

INTRODUCTION/AIMS: Nusinersen intrathecal administration can be challenging in spinal muscular atrophy (SMA) adults. We aimed to determine if the ultrasound (US)-assistance reduces the number of needle attempts and needle redirections needed for intrathecal drug administration and its impact on the procedure time, the incidence of adverse events (AEs), and patient satisfaction in these patients. METHODS: Fifty-eight patients aged 18 years and older scheduled for intrathecal nusinersen injection were enrolled and randomized (1:1 ratio) into Group 1 (nusinersen infusion with US-assisted technique) or Group 2 (nusinersen infusion with landmark-based technique). The number of attempts, number of redirections, periprocedural time, AEs and patient satisfaction were reported. Continuous variables were compared with the Student t-test or Wilcoxon rank sum test. Categorical variables were evaluated with the Chi-square test or Fisher's exact test in case of expected frequencies <5. The p-values <.05 were considered statistically significant. RESULTS: There were no statistical differences in the number of attempts, AEs, or patient satisfaction between the two groups. The number of needle redirections was significantly lower in the ultrasound group versus landmark-based group (p < .05) in both the overall group of patients and in the subgroup with difficult spines. The periprocedural time was about 40 seconds longer in US-group versus landmark-based group (p < .05). DISCUSSION: In SMA adults, US assistance reduces the number of needle redirections needed for intrathecal drug administration. These results suggest that the US assistance may be advantageous for nusinersen therapy to reduce the therapeutic burden of intrathecal infusion.

TROPIC: Transfascial Oblique Posterior Interbody Correction: Technical Note.

BACKGROUND: Adult spinal deformity is a common problem in today's aging adult population, particularly in the thoracolumbar spine. This can lead to severe pain and disability, leading to a poorer quality of life. Traditionally, open deformity correction has been the mainstay of treatment for these patients as it provides an excellent operative corridor; however, this comes with severe risk and high complication rates. There has been a trend toward more minimally invasive approaches to correct the deformity while preserving the muscle and soft tissue surrounding the bony spine across the fusion. METHODS: We describe a minimally invasive surgical technique through a Wiltse approach without invading the paraspinal musculature to gain access to the bony spine to perform lumbar interbody fusions and osteotomies. RESULTS: A total of 3 patients were identified for this technical note who underwent the transfascial oblique posterior interbody correction procedure for adult spinal deformity. The patients had severe coronal and rotational imbalances. We were able to achieve adequate correction through an approach without disturbing the spinal musculature and soft tissues. CONCLUSIONS: This technique provides benefits of spinal rotational and coronal plane correction and restores lordosis with current advancements of today's technologies without the downsides of an open surgical approach.

Expanded Combined Loading Injury Criterion for the Human Lumbar Spine Under Dynamic Compression.

Contemporary injury tolerance of the lumbar spine for under-body blast references axial compression and bending moments in a limited range. Since injuries often occur in a wider range of flexion and extension with increased moment contribution, this study expands a previously proposed combined loading injury criterion for the lumbar spine. Fifteen cadaveric lumbar spine failure tests with greater magnitudes of eccentric loading were incorporated into an existing injury criterion to augment its applicability and a combined loading injury risk model was proposed by means of survival analysis. A loglogistic distribution was the most representative of injury risk, resulting in optimized critical values of Fr,crit = 6011 N, and My,crit = 904 Nm for the proposed combined loading metric. The 50% probability of injury resulted in a combined loading metric value of 1, with 0.59 and 1.7 corresponding to 5 and 95% injury risk, respectively. The inclusion of eccentric loaded specimens resulted in an increased contribution of the bending moment relative to the previously investigated flexion/extension range (previous My,crit = 1155 Nm), with the contribution of the resultant sagittal force reduced by nearly 200 N (previous Fr,crit = 5824 N). The new critical values reflect an expanded flexion/extension range of applicability of the previously proposed combined loading injury criterion for the human lumbar spine during dynamic compression.