Introduction. Epidural steroid injection is an established treatment modality for intervertebral disc prolapse. It is a low-risk alternative to surgical intervention in some patients for whom noninvasive treatment has failed. Caudal epidural steroid injection is one of the most widely used methods for pain relief. The aim of this study was to determine the significance of same dose in different volume of caudal epidural steroid injection in the treatment of lumbar degenerative disc disease. Material/Methods. Prospective study was conducted during 2007 to 2009. 100 Patients were randomized in to two groups, of which 50 % (group A) received 4 ml of steroid with isotonic saline and remaining 50 % (group B) received 12 ml. Injection was given in prone position through a 22-G needle in to the epidural space through the sacral hiatus. The average follow-up was 18 months. Outcomes scores included the SF-36, Oswestry disability index and pain VAS and were recorded in the pre and post injection periods. Results. In group A, 18 patients had significant pain relief and 32 had no relief during the early period. Whereas in group B, 22 had significant pain relief and 28 had no relief. The quality of pain relief of 50% or greater was considered as significant. Follow up after 1 year does not show much difference. Group B had significant decrease in symptoms in the initial post injection period (P<0.05). Conclusions. The volume of steroid solution in the treatment of lumbar degenerative disc disease is significant in the early post injection period only

Aims. The aetiologies of common degenerative spine, hip, and knee pathologies are still not completely understood. Mechanical theories have suggested that those diseases are related to sagittal pelvic morphology and spinopelvic-femoral dynamics. The link between the most widely used parameter for sagittal pelvic morphology, pelvic incidence (PI), and the onset of degenerative lumbar, hip, and knee pathologies has not been studied in a large-scale setting. Methods. A total of 421 patients from the Cohort Hip and Cohort Knee (CHECK) database, a population-based observational cohort, with hip and knee complaints < 6 months, aged between 45 and 65 years old, and with lateral lumbar, hip, and knee radiographs available, were included. Sagittal spinopelvic parameters and pathologies (spondylolisthesis and degenerative disc disease (DDD)) were measured at eight-year follow-up and characteristics of hip and knee osteoarthritis (OA) at baseline and eight-year follow-up. Epidemiology of the degenerative disorders and clinical outcome scores (hip and knee pain and Western Ontario and McMaster Universities Osteoarthritis Index) were compared between low PI (< 50°), normal PI (50° to 60°), and high PI (> 60°) using generalized estimating equations. Results. Demographic details were not different between the different PI groups. L4 to L5 and L5 to S1 spondylolisthesis were more frequently present in subjects with high PI compared to low PI (L4 to L5, OR 3.717; p = 0.024 vs L5 to S1 OR 7.751; p = 0.001). L5 to S1 DDD occurred more in patients with low PI compared to high PI (OR 1.889; p = 0.010), whereas there were no differences in L4 to L5 DDD among individuals with a different PI. The incidence of hip OA was higher in participants with low PI compared to normal (OR 1.262; p = 0.414) or high PI (OR 1.337; p = 0.274), but not statistically different. The incidence of knee OA was higher in individuals with a high PI compared to low PI (OR 1.620; p = 0.034). Conclusion. High PI is a risk factor for development of spondylolisthesis and knee OA. Low pelvic incidence is related to DDD, and may be linked to OA of the hip. Level of Evidence: 1b. Cite this article: Bone Joint J 2020;102-B(9):1261–1267

In 2020, the COVID-19 pandemic meant that proceeding with elective surgery was restricted to minimise exposure on the wards. In order to maintain throughput of elective cases, our hospital was forced to convert as many cases as possible to same day procedures rather than overnight admission. In this retrospective analysis we review the cases performed as same day arthroplasty surgeries compared to the same period 12 months previous. We conducted a retrospective analysis of patients undergoing total hip and knee arthroplasties in a three month period between October and December in 2019 and again in 2020, in the middle of the SARS-CoV-2 pandemic. Patient demographics, number of out-patient primary arthroplasty cases, length of stay for admissions, 30-day readmission and complications were collated. In total, 428 patient charts were reviewed for the months of October-December of 2019 (n=195) and 2020 (n=233). Of those, total hip arthroplasties comprised 60% and 58.8% for 2019 and 2020, respectively. Demographic data was comparable with no statistical difference for age, gender contralateral joint replacement or BMI. ASA grade I was more highly prevalent in the 2020 cohort (5.1x increase, n=13 vs n=1). Degenerative disc disease and fibromyalgia were less significantly prevalent in the 2020 cohort. There was a significant increase in same day discharges for non-DAA THAs (2x increase) and TKA (10x increase), with a reciprocal decrease in next day discharges. There were significantly fewer reported superficial wound infections in 2020 (5.6% vs 1.7%) and no significant differences in readmissions or emergency department visits (3.1% vs 3.0%). The SARS-CoV-2 pandemic meant that hospitals and patients were hopeful to minimise the exposure to the wards and to not put strain on the already taxed in-patient beds. With few positives during the Coronavirus crisis, the pandemic was the catalyst to speed up the outpatient arthroplasty program that has resulted in our institution being more efficient and with no increase in readmissions or early complications

Degenerative disc disease (DDD) is a common cause of lower back pain. Calcification of the intervertebral disc (IVD) has been correlated with DDD, and is especially prevalent in scoliotic discs. The appearance of calcium deposits has been shown to increase with age, and its occurrence has been associated with several other disorders such as hyperparathyroidism, chondrocalcinosis, and arthritis. Trauma, vertebral fusion and infection have also been shown to increase the incidence of IVD calcification. Our data indicate that Ca. 2+. and expression of the extracellular calcium-sensing receptor (CaSR) are significantly increased in mild to severely degenerative human IVDs. In this study, we evaluated the effects of Ca. 2+. and CaSR on the degeneration and calcification of IVDs. Human donor lumbar spines of Thompson grade 2, 3 and 4 through organ donations within 24 hs after death. IVD cells, NP and AF, were isolated from tissue by sequential digestion with Pronase followed by Collagenase. Cells were expanded for 7 days under standard cell culture conditions. Immunohistochemistry was performed on IVD tissue to validate the grade and expression of CaSR. Free calcium levels were also measured and compared between grades. Immunocytochemistry, Western blotting and RT-qPCR were performed on cultured NP and AF cells to demonstrate expression of CaSR, matrix proteins aggrecan and collagen, catabolic enzymes and calcification markers. IVD cells were cultured in increasing concentrations of Ca. 2+. [1.0-5.0 mM], CaSR allosteric agonist (cincalcet, 1 uM), and IL-1b [5 ng/mL] for 7 days. Ex vivo IVD organ cultures were prepared using PrimeGrowth Disc Isolation System (Wisent Bioproducts, Montreal, Quebec). IVDs were cultured in 1.0, 2.5 mM Ca. 2+. or with cinacalcet for 21 days to determine effects on disc degeneration, calcification and biomechanics. Complex modulus and structural stiffness of disc tissues was determined using the MACH-1 mechanical testing system (Biomomentum, Laval, Quebec). Ca. 2+. dose-dependently decreased matrix protein synthesis of proteoglycan and Col II in NP and AF cells, similar to treatment with IL-1b. (n = 4). Contrarily to IL-1b, Ca. 2+. and cincalcet did not significantly increase the expression of catabolic enzymes save ADAMTS5. Similar effects were observed in whole organ cultures, as Ca. 2+. and cinacalcet decreased proteoglycan and collagen content. Although both Ca. 2+. and cinacalcet increased the expression of alkaline phosphatase (ALP), only in Ca. 2+. -treated IVDs was there evidence of calcium deposits in NP and AF tissues as determined by von Kossa staining. Biomechanical studies on Ca. 2+. and cinacalcet-treated IVDs demonstrated decreases in complex modulus (p<0.01 and p<0.001, respectively; n=5), however, only Ca. 2+. -treated IVDs was there significant increases stiffness in NP and AF tissues (p<0.001 and p<0.05, respectively; n=3). Our results suggest that changes in the local concentrations of calcium and activation of CaSR affects matrix protein synthesis, calcification and IVD biomechanics. Ca. 2+. may be a contributing factor in IVD degeneration and calcification

Introduction. Pelvic flexion and extension in different body positions can affect acetabular orientation after total hip arthroplasty, and this may predispose patients to dislocation. The purpose of this study was to evaluate functional acetabular component position in total hip replacement patients during standing and sitting. We hypothesize that patients with degenerative lumbar disease will have less pelvic extension from standing to sitting, compared to patients with a normal lumbar spine or single level spine disease. Methods. A prospective cohort of 20 patients with primary unilateral THR underwent spine-to-ankle standing and sitting lateral radiographs that included the lumbar spine and pelvis using EOS imaging. Patients were an average age of 58 ± 12 years and 6 patients were female. Patients had (1) normal lumbar spines or single level degeneration, (2) multilevel degenerative disc disease or (3) scoliosis. We measured acetabular anteversion (cup relative to the horizontal), sacral slope angle (superior endplate of S1 relative to the horizontal), and lumbar lordosis angles (superior endplates of L1 and S1). We calculated the absolute difference in acetabular anteversion and the absolute difference in lumbar lordosis during standing and sitting (Figure 1). Results. Nine patients had normal lumbar spines or scoliosis, and 11 patients had multilevel disc disease. The median change in cup anteversion for normal and scoliosis patients was 29° degrees (range 11° to 41°) compared to 21° degrees (range 1° to 34°) for multilevel disc disease patients (p=0.03). There was a positive correlation between the change in cup anteversion and the change in lumbar lordosis (p=0.01; Figure 2). From standing to sitting, cup anteversion always increased and lumbar lordosis always decreased. Conclusions. The change in cup anteversion from standing to sitting was variable in patients with normal, degenerative, and scoliosis lumbar spines. Patients with degenerative disc disease have less pelvic extension, and thus less acetabular anteversion in the sitting position compared to normal spines. This may increase their risk of posterior dislocation

Total disc replacement (TDR) is the gold standard for lumbar degenerative disc disease in selected patient groups. Traditional TDR designs benefit from a wealth of literature and use a polyethylene inlay pseudo-disc between two metal endplates. There is scarce literature for novel monomodular implants that form an artificial construct of woven annulus and central nucleus, providing physiological motion preservation. The aim was to compare the evolving changes to radiological position between monomodular and traditional implants and assess the relationship of migration with bone densitometry. This retrospective series of consecutive patients undergoing TDR under a single surgeon recorded demographics, co-morbidities, previous surgery and clinical outcomes. Measurements of endplate subsidence, lordosis and spondylolisthesis taken from weight-bearing erect x-rays at 0, 3, 6 and 12 months. Radiological outcomes were compared against CT bone densitometry. 33 monomodular and 13 traditional implants. Mean age 40 years. All patients had degenerative disc disease. Monomodular and traditional implants were as likely to develop lordosis (p=0.32), endplate subsidence (p=0.78) or spondylolisthesis (p=0.98). Comparison between endplate subsidence and low bone densitometry were insignificant (p=0.47). Developing lordosis in the monomodular implant was related to low bone density; mean 134vs.184mg/cm. 3. (p=0.018). Three monomodular implants developed a posterior hinge after migrating into lordosis. One traditional implant dislocated, requiring emergency fusion. Radiological outcomes are comparable between traditional and monomodular implants. The larger endplate-footprint of the monomodular implant did reduce subsidence. Monomodular implants pivoting on a posterior hinge may fail early. Bone densitometry may identify patients who will drift into lordosis

Obesity is an increasing public health concern associated with increased perioperative complications and expense in lumbar spine fusions. While open and mini-open fusions such as transforaminal lumbar interbody fusion (TLIF) and minimally invasive TLIF (MIS-TLIF) are more challenging in obese patients, new MIS procedures like oblique lateral lumbar interbody fusion (OLLIF) may improve perioperative outcomes in obese patients relative to TLIF and MIS-TLIF. The purpose of this study is to determine the effects of obesity on perioperative outcomes in OLLIF, MIS-TLIF, and TLIF. This is a retrospective cohort study. We included patients who underwent OLLIF, MIS-TLIF, or TLIF on three or fewer spinal levels at a single Minnesota hospital after conservative therapy had failed. Indications included in this study were degenerative disc disease, spondylolisthesis, spondylosis, herniation, stenosis, and scoliosis. We measured demographic information, body mass index (BMI), surgery time, blood loss, and hospital stay. We performed summary statistics to compare perioperative outcomes in MIS-TLIF, OLLIF, and TLIF. We performed multivariate regression to determine the effects of BMI on perioperative outcomes controlling for demographics and number of levels on which surgeries were operated. OLLIF significantly reduces surgery time, blood loss, and hospital stay compared to MIS-TLIF, and TLIF for all levels. MIS-TLIF and TLIF do not differ significantly except for a slight reduction in hospital stay for two-level procedures. On multivariate analysis, a one-point increase in BMI increased surgery time by 0.56 ± 0.47 minutes (p = 0.24) in the OLLIF group, by 2.8 ± 1.43 minutes (p = 0.06) in the MIS-TLIF group, and by 1.7 ± 0.43 minutes (p < 0.001) in the TLIF group. BMI has positive effects on blood loss for TLIF (p < 0.001) but not for OLLIF (p = 0.68) or MIS-TLIF (p = 0.67). BMI does not have significant effects on length of hospital stay for any procedure. Obesity is associated with increased surgery time and blood loss in TLIF and with increased surgery time in MIS-TLIF. Increased surgery time may be associated with increased perioperative complications and cost. In OLLIF, BMI does not affect perioperative outcomes. Therefore, OLLIF may reduce the disparity in outcomes and cost between obese and non-obese patients

As the intervertebral disc is largely avascular, needle injection is the most practical method for delivery of therapeutic agents used in treatments for degenerative disc disease. Intradiscal pressure increases during injection, and insufficient recovery time prior to needle retraction may result in injectate leakage. In order to determine the maximum pressure and post-injection recovery time for a given injection volume and rate, an analytical model of intradiscal injection was developed and calibrated experimentally. A governing equation was derived defining intradiscal pressure as a function of effective permeability, initial elastic stiffness, nonlinear stiffness term, and injection rate. The equation was solved using a fourth order Runge-Kutta routine with a 0.05s time step and a ramp-dwell injection. The model was calibrated by performing controlled intradiscal injections on five bovine caudal intervertebral discs. Three had adjacent vertebrae intact, while two were separated from vertebrae and constrained between porous stainless steel platens. A syringe driven by a linear actuator was used to inject phosphate buffered saline through a 21g hypodermic needle inserted radially into the disc to a depth of one half of the disc diameter. Injection was performed at a rate of 75μL/s to a volume of 250μL followed by a 240s dwell. Fluid pressure was recorded during both the injection phase and subsequent recovery phase. For each experimental pressure vs time trace, model parameters were varied in order to obtain an optimal fit. The model was run with the average parameter values across a grid of possible injection protocols, with injection volume ranging from 30 to 300μL and injection time ranging from 0.1 to 5s. For each case, peak pressure and time required to reach a 1kPa threshold were recorded. Experimentally measured peak pressure ranged from 68 to 88kPa. Pressure at the end of the 240s dwell ranged from 49 to 69kPa. There was no apparent difference between discs with and without endplates. Leakage of fluid following needle retraction was observed in all specimens. Experimental data were well fit by the analytical model, which predicted higher peak pressure and longer recovery time with increasing volume, from approximately 1500s at 30μL to nearly 3000s at 300μL. The model was nearly insensitive to injection rate. The experimental data confirm pressurization of the disc during injection and injectate leakage resulting from insufficient recovery time. The model predicts that the time required to recover to below threshold leakage pressure is impractically long for both laboratory and clinical injection protocols. Similar behavior with and without endplates confirms that fluid flow is limited by permeability of the tissue itself, not the boundary conditions. Slow recovery is likely attributable to the fact that peak injection pressures were lower than the hydraulic swelling pressure of the nucleus pulposus, which has been reported to be approximately 140kPa. Due to the high swelling pressure of the nucleus pulposus, it is unlikely that intradiscal injection procedures can be performed without substantial injectate leakage following needle retraction

Revision surgery and surgery in previously operated areas are associated with an increased infection risk. In such situations, aggressive surgical debridement may be necessary to control and eradicate the infection. Full thickness defects resulting from such debridement present as a challenge. In most cases, an association of various methods, both surgical and non-surgical, is necessary. Our goal is to describe the use of vaccum dressings as an effective way to deal with extensive and infected dorsolumbar surgical defects, while avoiding the use of myocutaneous flaps. This is a retrospective and descriptive case report based on data from clinical records, patient observation and analysis of complementary exams. We present the case of a 57-years-old obese woman with prior history of double approach with posterior instrumentation and spine arthrodesis (D3 to L4) due to severe dorsolumbar adolescent idiopathic scoliosis. She presented to our consult 42 years after surgery, complaining of lower back pain. Clinical observation and imaging exams demonstrated degenerative disc disease in L5-S1 and L5 anterolisthesis. There was also distal instrumentation breakage (right L4 pedicular screw and contralateral rod) with pseudarthrosis suspicion. Distal instrumentation was removed and no pseudarthrosis was found. Therefore, posterior instrumentation and arthrodesis was performed, from L4 to S1. Surgery went without complications. One week after surgery, patient developed fever and inflammatory signs at the surgical incision, with purulent oozing. Escherichia coli and Proteus mirabilis were identified as the causative agents. Decision was made to remove both lumbar and distal dorsal instrumentation and perform aggressive debridement and lavage, with debridement surgery being repeated twice. Finally, a full thickness defect with approximately 20cm long and 6cm wide resulted from the debridement. A vacuum dressing was then applied, for 5 weeks, with progressive decrease in clinical and analytical inflammatory parameters and wound closure. Four months after the initial surgery, patient was discharged with complete defect closure and reepithelialization. This dressing technique provided a sound solution for defect resolution, as well as an important aid for infection control. It proved to be a viable option in an extensive defect, when surgical flap techniques and traditional dressing techniques could not provide a complete solution

Testing potential therapeutics in the regeneration of the disc requires the use of model systems. Although several animal models have been developed to test intervertebral disc (IVD) regeneration, application becomes costly when used as a screening method. The bovine IVD organ culture system offers an inexpensive alternative, however, in the current paradigm, the bony vertebrae is removed to allow for nutrient diffusion to disc cells. This provides limitations on the conditions and strategies one can employ in investigating IVD regeneration and mechanisms in degenerative disc disease (i.e. complex loading). Although one method has been attempted to extend the survival of bovine vertebrae containing IVDs (vIVD) cell viability declined after two weeks in culture. Our goal was to develop and validate a long-term organ culture model with vertebral bone, which could be used subsequently for studying biological repair of disc degeneration and biomechanics. Preparation of vIVDs: Bovine IVDs from the tails of 22–28-month-old steers were prepared for organ culture by parallel cuts through the adjacent vertebral bodies at 1cm from the endplates using an IsoMet®1000 Buehler precision sectioning saw. vIVDs were split into two groups: IVDs treated with PrimeGrowth Media kit (developed by Intervertech and licensed to Wisent Bioproducts) and IVDs with DMEM. The PrimeGrowth group was incubated for 1h in PrimeGrowth Isolation Medium (Cat# 319–511-EL) and the DMEM group for 1h in DMEM. After isolation, IVDs were washed in PrimeGrowth Neutralisation Medium (Cat# 319–512-CL) while the other IVDs were washed in DMEM. The discs isolated with PrimeGrowth and DMEM were cultured for up to 5 months in sterile vented 60 ml Leakbuster™ Specimen Containers in PrimeGrowth Culture Medium (Cat# 319–510-CL) and DMEM with no mechanical load applied. Live/Dead Assay: vIVDs cultured for 1 or 5 months were dissected and cell viability was assessed in different regions by confocal microscopy using Live/Dead® (Invitrogen) fluorescence assay. Glucose Diffusion: After one month of culture, vIVDs were incubated for 72h in diffusion medium containing PBS (1x), CaCl2 (1mM), MgCl2 (0.5mM), KCl2 (5mM), 0.1% BSA and 150µM 2-NDBG, a D-glucose fluorescent analogue. Discs were dissected and IVD tissues were incubated in guanidinium chloride extraction buffer. Extracts were measured for fluorescence. After 5 months in culture, vIVDs prepared with PrimeGrowth kit demonstrated approximately 95% cell viability in all regions of the disc. However, dramatic reductions (∼90%) in vIVD viability were measured in DMEM group after 1 month. vIVD viability was related to the amount of 2-NDBG incorporated into the disc tissue. We have developed a novel method for isolating IVDs with vertebral bone capable of long-term viability. This method may not only help in the discovery of novel therapeutics in disc regeneration, but could also advance our understanding on complex loading paradigms in disc degeneration

Calcification of the intervertebral disc (IVD) has been correlated with degenerative disc disease (DDD), a common cause of low back pain. The appearance of calcium deposits has been shown to increase with age, and its occurrence has been associated with several other disorders such as hyperparathyroidism, chondrocalcinosis, and arthritis. Trauma, vertebral fusion and infection have also been shown to increase the incidence of IVD calcification. The role of IVD calcification in the development DDD is unknown. Our preliminary data suggest that ionic calcium content and expression of the extracellular calcium-sensing receptor (CaSR), a G protein-coupled receptor (GPCR) and regulator of calcium homeostasis, are increased in the degenerated discs. However, its role in DDD remains unclear. IVD Cells: Bovine and normal human IVD cells were incubated in PrimeGrowth culture medium (Wisent Bioproducts, Canada; Cat# 319–510-CL, −S1, and S2) and supplemented with various concentrations of calcium (1.0, 1.5, 2.5, 5.0 mM), a CaSR agonist [5 µM], or IL-1β [10 ng/ml] for 7 days. Accumulated matrix protein was quantitated for aggrecan and type II collagen (Col II) by Western blotting. Conditioned medium was also collected from cells treated for 24h and measured for the synthesis and release of total proteoglycan using the DMMB assay and Western blotting for Col II content. IVD Cultures: Caudal IVDs from tails of 20–24 month old steers were isolated with the PrimeGrowth Isolation kit (Wisent Bioproducts, Canada). IVDs were cultured for 4 weeks in PrimeGrowth culture medium supplemented with calcium (1.0, 2.5, or 5.0 mM), or a CaSR agonist [5 µM]. Cell viability was measured in NP and AF tissue using Live/Dead Imaging kit (ThermoFisher, Waltham, MA), to determine if Ca2+ effects cell viability end the expression of aggrecan and Col II was evaluated in the IVD tissue by Western blotting. Histological sections were prepared to determine total proteoglycan content, alkaline phosphatase expression and degree of mineralisation by von Kossa staining. The accumulation of aggrecan and Col II decreased dose-dependently in IVD cells following supplementation with calcium or the CaSR agonist. Conditioned medium also demonstrated decreases in the synthesis and release of proteoglycan and collagen with increasing Ca2+ dose or direct activation of the CaSR with agonist. A similar phenomenon was observed for total proteoglycan and aggrecan and Col II in IVDs following calcium supplementation or the CaSR agonist. In addition to decreases in Col II and aggrecan, increases in alkaline phosphatase expression and mineralisation was observed in IVDs cultured in elevated Ca2+ concentrations without affecting cell viability. Our results suggest that changes in the local concentrations of calcium are not benign, and that activation of the CaSR may be a contributing factor in IVD degeneration. Determining ways to minimise Ca2+ infiltration into the disc may mitigate disc degeneration

Introduction. MRI imaging is carried out to identify levels of degenerative disc disease, and in some cases to identify a definite surgical target at which decompression should take place. We wanted to see if repeat MRI scans due to a prolonged time between the initial diagnostic MRI scan of the lumbar sacral spine, and the MRI scan immediately pre-operatively, due for the desire for a ‘fresh’ MRI scan pre-operatively, altered the level or type of procedure that they would have. Methods. This was a retrospective observational cohort study. Inclusion criteria- all patients with more than one MRI scan before their surgical procedure on the lumbar sacral spine, these were limited to patients that had either, discectomy, microdiscectomy, laminotomy decompression, laminectomy decompression and fusion, and posterior lumbar interbody fusion. Exclusion criteria- all patients with anterior approaches, all patients without decompression and all non lumbar sacral patients. Outcome measures were if there was a change between the pre-operative MRI scans, which would have changed the operative level of decompression, added other levels of decompression or type of surgery than primarily decided. Results. 84 patients were identified with our inclusion criteria with two or more pre-operative MRI scans. The repeat MRI did not change the surgical target for all 84 patients. Conclusion. Repeat MRI scanning does not alter the surgical target level, and therefore does not change management. It can delay the initial primary procedure which can lead to progressive neurology, which may be irreversible and should be avoided unless the distribution of neurology has changed

Anterior cervical discectomy and fusion for radiculopathy and myelopathy has the complication of the development of adjacent segment degeneration. Furthermore, reoperations may be required to treat complications of fusion, such as non-union, graft collapse, or expulsion. Cervical disc arthroplasty lays claim to preserving cervical motion and reducing the risks of adjacent segment disease in the treatment of cervical radiculopathy. We performed a prospective study in order to evaluate the radiological and clinical outcomes of cervical disc arthroplasty for single or two level disc disease with associated radiculopathy. Our study included a total of 26 patients. Each patient had cervical radiculopathy from nerve root compression due to degenerative disc disease at one or two levels. Diagnosis was made preoperatively on clinical examination and by means of MRI scanning. Each patient also had preoperative flexion and extension cervical spine x-rays in order to assess pre-operative range of neck movement. The outcomes of surgery were assessed prospectively. Range of motion at final follow-up was measured by flexion and extension view x-rays of the cervical spine. Clinical outcome was assessed by means of VAS scores for pain, SF12 for mental and physical health and the neck disability index (NDI). All complications were recorded. 14 of the patients had a follow-up for two years and the remaining 12 patients had a follow-up for one year. A Discovery disc arthoplasty by Scient'X was the implant used in all patients. A standard anterior cervical approach was used to achieve decompression and for the implantation of the prosthesis. On follow-up all patients had either maintenance or an improvement in the range of movement. There was no evidence of progression of degeneration in the segments adjacent to the arthroplasty prosthesis. Improvements in SF12, VAS, and NDI scores were seen from preoperative levels in 25 of the 26 patients. Complications included one patient with a horse voice post-operatively and one patient with minimal improvement of radicular symptoms. Post-operative MRI scanning demonstrated adequate decompression with this procedure and showed no evidence of progression of adjacent segment disease. There were no cases of implant subsidence or dislocations. We have found cervical disc arthroplasty to produce good clinical outcomes when used for single or two level cervical radiculopathy whilst maintaining neck motion with an acceptable complication rate. A longer follow-up is needed to further assess the risk of development of adjacent segment disease but we did not discover the development of adjacent segment disease in our study with a follow-up of upto 2 years

Purpose. Degenerative changes of the lumbar motion segment often lead to stenosis of the spinal canal or neuroforamen. Axial lumbar interbody fusion (AxiaLIF) is intended to indirectly increase and stabilize foraminal dimensions by restoring disc height in patients with degenerative disc disease, thereby relieving axial and radicular pain. Therefore, this study investigated the effects of AxiaLIF on anterior disc height, posterior disc height, foraminal height and foraminal width as well as to determine the effectiveness of this minimally-invasive technique for indirect decompression and restoration of disc height. Method. Eighty-one patients who underwent a 360 degree lumbar interbody fusion at L4-S1 and L5-S1 with AxiaLIF between November 2008 and May 2010 and satisfied all inclusion criteria were included. The preoperative and three-month postoperative digital radiographs were reviewed and analyzed. Disc heights were measured in the planes of the anterior and posterior surfaces of the adjacent vertebral bodies. Foraminal height was measured as the maximum distance between the inferior margin of the pedicle of the superior vertebra and the superior margin of the pedicle of the inferior vertebra. Foraminal width was measured as the shortest distance between the edge of the superior facet of the caudal vertebra and the posterior edge of inferior endplate of the cranial vertebra. Potential magnification error between pre- and post-operative radiographs was corrected using the anterior vertebral height of L5 vertebra. Results. Our study shows that there is a mean increase of 42.0% in posterior disc height (PDH) at L4-5 and 21.5% in anterior disc height (ADH) at L4-5 and PDH mean increase of 33.6% and 16.3% in ADH at L5-S1 in two-level AxiaLIF cases. Similarly the mean change in foraminal height (FH) was 12.6% at L4-5 and 10.8% at L5-S1 in 2-levels AxiaLIF. The mean change in foraminal width (FW) at L4-L5 was 19.9% and 29.1% at L5-S1 in 2-levels AxiaLIF. In the single level AxiaLIF group, the mean change in PDH was 43.1%, the ADH change was 17.5%, the average change in FH was 14.4%, and mean change in FW was 25.3%. The change is reflected as a percentage of the preoperative value. All changes from preoperative to postoperative values were statistically significant. Conclusion. AxiaLIF appears to be an effective minimally invasive device to increase disc height and neuroforaminal area. Our findings appear equivalent to anterior lumbar interbody fusion and transforaminal lumbar interbody fusion in terms of indirect decompression and increase in disc height. This, in combination with the added benefit of preserving the annulus, anterior longitudinal ligament, and posterior longitudinal ligament, suggests the AxiaLIF is an excellent alternative for this patient population. However, additional follow-up studies are necessary to confirm the long-term ability of the implant to maintain fusion and preserve the improvements in disc and foraminal area

Purpose. A change in lumbar lordosis can affect the outcome following lumbar fusion, and intraoperative positioning is a prime determinant of the postoperative lordosis. The purpose of this study is to determine the change in lordosis and sacral slope (SS) following axial lumbar interbody fusion (AxiaLIF). Method. We retrospectively reviewed 81 patients who underwent a 360 lumbar interbody fusion at L4-5/L5-S1 (two-level procedure) or solely at L5-S1 (one-level) for degenerative disc disease and spondylolithesis utilizing the AxiaLIF with posterior segmental instrumentation. For the two-level procedures, 25 patients had the AxiaLIF placed first and 27 had pedicle screws placed first. For the one-level procedures, 11 patients had the AxiaLIF placed first and 18 had pedicle screws placed first. Standing lateral preoperative radiographs were compared to standing lateral postoperative films. Lumbar Cobb angles were measured at L1-S1, L4-S1 and individual lumbar levels. SS was measured for sacral version. Results. Of the 81 patients studied, 29 underwent one-level AxiaLIF, and 52 underwent two-level AxiaLIF. For the two-level population, there were statistically significant changes (P less than 0.05) in Cobb angles pre- vs. postoperative at the L4-S1, L2-3, and L4-5 levels, but none other. The percent lordosis from L4-S1 pre- vs. postoperative was also noted to be significant. The pre- vs. postoperative Cobb angle comparisons for the one-level population were not found to be significant. The percentages having a greater than or equal to 10 degree change in total lordosis and lordosis from L4-S1 in both one- and two-level groups were similar at ∼20%. There was no difference in either group in percentage having a greater than or equal to five degree change at individual lumbar segments although there was a trend at both L5-S1 and the SS towards less change with the pedicle screws placed first. Conclusion. A significant portion of both single and multilevel fusions with AxiaLIF had a statistically significant change at the L4-5 and L4-S1 levels. In general, there is a small decrease in lordosis at the bottom two segments and SS with reciprocal changes at the proximal levels. The percentage of total lordosis from the L4-S1 level decreased significantly in the multilevel group. Roussouly lordosis type three (well-balanced) was relatively protected from change in lordosis. Placing pedicle screws prior to placing the AxiaLIF in one- and two- level procedures may lead to an improved sagittal alignment. Further observation of this cohort will determine if the change in alignment will impact outcomes or accelerate adjacent level disease

Purpose. Nucleus pulposus (NP) replacements represent a less invasive alternative for treatment of early stage degenerative disc disease (DDD). Hydrogel based NP replacements are of particular interest as they can be injected/implanted using minimally invasive surgical (MIS) techniques to re-establish mechanical integrity and as a scaffold for regeneration. A thiol-modified hyaluronan elastin-like polypeptide (TMHA/EP) hydrogel crosslinked using polyethylene diacrylate has shown promise as a potential NP replacement for DDD in vitro. This study aims to assess the mechanical properties of this hydrogel when injected into an induced early stage DDD porcine model and to determine the optimal injection method for delivery. It is hypothesized that minimally invasive injection of the TMHA/EP material can restore mechanical behaviour of spinal motion segments in early stage DDD. Method. Intervertebral disc (IVD) degeneration was enzymatically induced in L2-L3 and L4-L5 lumbar levels in 10 Yorkshire boars using chondroitinase ABC (n=20 discs). An additional three animals served as healthy controls (n=6 discs). Following a four-week degradation period, the TMHA/EP solution (250microL in a 3:1 weight ratio) was injected into the degenerate NP of 16 discs by one of two MIS techniques: A direct 18G needle injection or a modified kyphoplasty technique (MKT) in which a balloon angiocatheter was inserted through an 11G trocar into the IVD and inflated to create a cavitary defect that was then filled with the hydrogel. Excised motion segments were tested in axial compression under a load of 400N and in axial rotation (AR), lateral bending (LB) and flexion/extension (FE) at 5Nm. Range of motion (ROM), neutral zone (NZ) length, NZ stiffness (NZStiff) and axial compressive stiffness (ACStiff) were quantified. Results. The degenerate control motion segments were, in general, found to be significantly less stiff and more flexible than the healthy controls. In comparison to the degenerate controls, direct injection of TMHA/EP demonstrated increased ACStiff and AR NZStiff (23%, 77%; p<0.05) and the MKT yielded a significant increase in AR NZStiff (88%) with a trend towards increased FE NZStiff (253%, p=0.089). Following TMHA/EP augmentation, direct injection and MKT treated IVDs demonstrated similar stiffness to healthy intact controls (p=0.519–1.000). Both ROM and NZ length in AR significantly increased following degeneration of the IVDs as compared to healthy controls (49%, 63%) In comparison to degenerate controls, both MIS techniques showed similar significant decreases in AR ROM (32%, 33%) and AR NZ length (35%, 32%). Both injection methods worked to restore motion to levels similar to healthy controls (p=0.173–1.00). Differences were not detected between the two treatment groups for all outcome variables (p=0.115–0.916). Conclusion. This study demonstrated the ability of the TMHA/EP composite to restore initial biomechanical function in early stage DDD independent of the MIS technique

Nowadays many new minimally invasive techniques are experienced to perform lower lumbar interbody fusion in attempt to decrease the complications related to open anterior approach. AxiaLIF (axial lumbar interbody fusion) system is a percutaneous transacral approach that exploits the virtual presacral retroperitoneal space to perform annulus-sparing discectomy and interbody instrumented fusion of lower lumbar disc spaces. Additioning posterior percutaneous instrumentation, a robust axial construct is placed which restores disc height, sagittal balance and lordosis with minimal muscle dissection, blood loss and postoperative pain. Via fluoroscopically-guided approach, AxiaLIF procedure creates a presacral retroperitoneal corridor in the midline through a paracoccigeal skin incision of 2-3 cm. This space is void of neuro-vascular major elements. A safe working cannula is put in and docked in the S1-S1 entry level and a transacral channel is realized gaining the central space of the disc. A 360° annulus-sparing radial discectomy is performed with special cutters even in case of collapsed disc space and the bone graft is inserted. The following screwing of AxiaLIF rod restores disc height via distraction if necessary, decompresses the neural foramen indirectly and undertakes instantaneous rigid fixation of adjacent vertebral bodies. Using the same incision point and trajectory through the presacral space as AxiaLIF, it is possible to realized a similar procedure L4-S1 vertebral fusions called AxiaLIF 2L. Between february 2009 and may 2010 25 patients (16F:9M) affected by degenerative disc disease (17) and grade 1 or 2 spondylolisthesis (8) were included in this study. Evaluated outcomes were the amount of bleeding, the presence of presacral hematoma, the functional recovery time, the surgery time rate, the x-ray time rate, the complication rate (infection, pelvic visceral injury, postoperative pain). 21 of 25 patients underwent AxiaLIF L5-S1 procedures, 4 of these with a stand alone implant and 17 followed by posterior instrumentation. In the remaining 4 patients, a AxiaLIF 2L L4-S1 procedures is performed. 4 of 25 patients had a perioperative suction drenage. Mean operative time for L5-S1 AxiaLIF procedure was 49 minutes. A 2. nd. p.o.d. CT pelvic scan of undrained and drained groups showed a mean presacral hematoma of 45 cc and 17 cc respectively reduced one month later to a mean value of 19 cc and 3 cc. Hemoglobin rate mainly reduced of 1,7 g/dL between pre and postoperative time. At one month all patients improved their quality of life significantly but one had a gluteal pain. No patient had perioperative infections or pelvic visceral injuries or required blood transfusions. This study seems to assess that AxiaLIF procedure is a minimally invasive lower spine techique actually. The presacral hematoma presence seems to have no side effect and it may be prevented by perioperative drainage. More large studies are needed to confirm our results

Introduction. The majority of spine patients present with discogenic low back pain, originating from either degenerative disc disease (DDD) or internal disc disruption (IDD). Successful treatment of this patient population relies on obtaining precision diagnosis and careful patient selection, as well as matching the pathology with reliable technology. Total disc replacement (TDR), as an alternative to spinal fusion in the treatment of DDD or IDD, has been studied and reported for several decades in long-term follow-up studies and in several randomized control trials. This prospective study presents a single surgeon experience with two-level CHARITÉ® TDR in 84 consecutive patients, with minimum follow-up of 5 years. The aims of the study were to assess the clinical outcomes of two-level TDR in patients with DDD/IDD. Based on the literature review conducted, this study is considered the largest single surgeon series experience with the two-level CHARITÉ® TDR in the treatment of lumbar DDD, with a minimum follow-up of 5 years reported to date. Materials and Methods. Between January 1997 and March 2006, n=84 consecutive patients underwent two-level TDR for the treatment of two-level DDD or IDD discogenic axial low back pain with or without radicular pain. All patients completed self-assessment outcome questionnaires pre and postoperatively (3, 6, 12 months, and yearly thereafter), including Oswestry Disability Index (ODI), Roland-Morris Disability Questionnaire (RMDQ) and Visual Analogue Score (VAS) for back and leg pain. Results. For the n=84 patients, the mean follow-up was 94.34±2.19 months (range = 62–150). The mean age was 49.6±0.94. The mean surgical time was 91±3.16 minutes and the mean blood loss was 207.5±30.62 mls. The main diagnosis was two-level DDD in 63 (76.8%) patients, followed by one-level disc herniation and one-level DDD. Seventy-three (89%) patients underwent L4-5 L5-S1 TDR and 9 (11%) patients underwent L3-4 L4-5 TDR. At all follow-up points, patients demonstrated significant improvement in ODI, RMDQ, and VAS back and leg pain scores compared to pre-operative scores (p < 0.001). The mean improvement between pre-op and last follow-up was 33.3 (66.8%) and 13.23 (74%) for ODI and RMDQ, respectively. Similarly, that was 54.8 (69 %%) and 34.8 (65%) for VAS back and VAS leg pain, respectively. At least 87.8% of the patients rated their satisfaction as good/excellent at any follow-up point. At 5 years follow-up, 54 patients (65.9%) rated their satisfaction as excellent, 19 (23.2%) as good, 7 (8.5%) as satisfactory and 2 (2.4%) as poor. Two patients (2 out of 84, 2.38%) required early revision of one of the prostheses due to failure of indication and/or failure of technique. There has been no device failure. One patient required surgery for adjacent segment disease (1.19%). Conclusion. This study has shown that statistically significant reductions in pain and functional outcomes can be obtained in patients at a minimum follow-up of 5-years following 2-level TDR for the treatment of multilevel DDD or IDD. The clinical benefits of this procedure is supported by the data, with the outcomes reflecting a precision diagnosis, stringent patient selection criteria, and a standardised surgical technique