Disc Space Height Research Articles

Pedicle Screw with Cement Augmentation in Unilateral Transforaminal Lumbar Interbody Fusion: A 2-Year Follow-Up Study

To evaluate safety and efficacy of pedicle screw with polymethyl methacrylate (PMMA) augmentation in unilateral transforaminal lumbar interbody fusion (uTLIF) in osteoporotic patients. We randomly divided 50 osteoporotic patients with degenerative lumbar diseases diagnosed between February 2014 and November 2015 into 2 groups. One group underwent standard uTLIF, and the other group underwent uTLIF with PMMA augmentation. All patients were scheduled to attend a series of regular follow-up evaluations. Oswestry Disability Index, Japanese Orthopaedic Association score, visual analog scale score, lumbar lordotic angle, segmental lordotic angle, and disc space height (DSH) at each follow-up were collected and analyzed. The 2-year follow-up was completed by 24 patients in the uTLIF group and 23 patients in the PMMA group. Oswestry Disability Index, Japanese Orthopaedic Association score, and visual analog scale score showed significant improvements after surgery in both groups, with no significant difference between groups. DSH in the uTLIF group was 8.7 ± 2.3 mm and in the PMMA group was 10.7 ± 1.6 mm. Fusion rate in the uTLIF group was 19/24 and in the PMMA group was 21/23. DSH and fusion rate in the PMMA group were higher than those in the uTLIF group. No severe complications were observed after PMMA injection. Pedicle screw with PMMA augmentation can increase fixation stability and reduce DSH loss in uTLIF. Moreover, PMMA in the vertebral body did not impede the interbody fusion ability in uTLIF.

Time Course of Radiologic Changes After Lumbar Total Disc Replacement: Experience of Single Institute With Minimum 5-Year Follow-up.

This was a retrospective observatory analysis study. The purpose of this study was to evaluate long-term safety and therapeutic effectiveness of the lumbar total disc replacement (TDR) using ProDisc-L by analyzing the radiologic changes at the index and adjacent levels in minimum 5-year follow-up. Early successful clinical results of lumbar TDR have been reported. However, few reports have published its therapeutic effectiveness and radiologic degenerative changes at the index and adjacent segments in the long term. Forty-three patients were followed-up for at least 60 months. Radiologic changes were assessed by segmental range of motion (ROM) at the index and adjacent levels, global lumbar lordosis, and disc space height (DSH). The magnetic resonance imaging and computed tomographic scans were used to determine the facet arthrosis and intervertebral disc degeneration at the index and adjacent levels. Gradual decrements of DSH restoration were observed until the last follow-up. Mean global and segmental ROM of index segments were significantly reduced (P=0.044, 0.00) at the last visit. There were 21 patients (48.8%) with no motion at index segment (ROM<0.5 degrees) at the last visit. Among the 56 segments operated on, progression of facet arthrosis was observed in 30.3% of index segments and 10.9% of adjacent segments. None of the postoperative radiologic parameters included in the present study presented significant correlation with clinical outcome. The study demonstrates that only half of the lumbar TDR patients can maintain segmental motion at the index level >5-year after surgery and TDR provides a good clinical outcome postoperatively regardless of motion preservation or DSH height preservation at the last follow-up. After TDR, the degenerative changes in the index and adjacent segments advanced as compared with our previous report of 2-year follow-up, however, these changes did not appear to exert negative influence upon clinical outcomes.

Low Back Pain - Recreational Soccer Player

HISTORY: A 21-year-old female recreational soccer player presented with intermittent right-sided low back pain for two years. She denied any trauma or inciting event. Pain was localized to the right lumbosacral region without radiating leg pain and was described as dull and aching. It was rated on average 5/10 on a numerical rating scale and associated with nausea when pain worsened. Symptoms were worse with prolonged sitting, and several times in the last month she reported worsening of typical pain with alcohol intake. She denied leg weakness, numbness, or bowel/bladder dysfunction. She participated in six weeks of physical therapy, which helped with nausea and pain with sitting, but she continued to have pain with alcohol consumption. PHYSICAL EXAM: Full and symmetric strength, sensation, and reflexes. Mild lumbar dextroscoliosis. No palpable step-offs. Tenderness over right lumbar paraspinals and above right iliac crest. No tenderness over PSIS. Full, non-painful range of motion with lumbar flexion and extension. No pain with facet loading. Full, non-painful hip range of motion. Negative FABER, FADIR, and straight leg raise test bilaterally. DIFFERENTIAL DIAGNOSIS: 1. Discogenic pain 2. Facet-mediated pain 3. Disc herniation 4. Muscular strain 5. Sacroiliac joint dysfunction 6. Intrabdominal/ intrapelvic etiology 7. Neoplasm TESTS AND RESULTS: 1. Lumbar spine X-rays: -Normal alignment, normal vertebral body and disc space height -Partial lumbarization of S1 vertebral body -Five degrees of lumbar dextroscoliosis 2. MRI lumbar spine: -Lumbarization of S1 vertebral body -Normal disc heights and signal -Normal central canal and neural foramen size throughout lumbar spine -T1/T2 hyperintensity within S2 vertebral body, likely lipoma -Increased T2 signal medial to right kidney suggestive of hydronephrosis 3. Renal ultrasound: -Moderate right hydronephrosis with extrarenal pelvis. No nephrolithiasis. 4. Renogram with furosemide: - Right kidney with blunted flow and delayed clearance improved slightly with furosemide, consistent with partial obstruction at right ureteropelvic junction FINAL/WORKING DIAGNOSIS: Ureteropelvic junction obstruction causing Dietl’s crisis TREATMENT AND OUTCOMES: 1. Referral to urology 2. Resolution of pain and improvement in renal function after pyeloplasty

Low Back Pain - Recreational Soccer Player

HISTORY: A 21-year-old female recreational soccer player presented with intermittent right-sided low back pain for two years. She denied any trauma or inciting event. Pain was localized to the right lumbosacral region without radiating leg pain and was described as dull and aching. It was rated on average 5/10 on a numerical rating scale and associated with nausea when pain worsened. Symptoms were worse with prolonged sitting, and several times in the last month she reported worsening of typical pain with alcohol intake. She denied leg weakness, numbness, or bowel/bladder dysfunction. She participated in six weeks of physical therapy, which helped with nausea and pain with sitting, but she continued to have pain with alcohol consumption. PHYSICAL EXAM: Full and symmetric strength, sensation, and reflexes. Mild lumbar dextroscoliosis. No palpable step-offs. Tenderness over right lumbar paraspinals and above right iliac crest. No tenderness over PSIS. Full, non-painful range of motion with lumbar flexion and extension. No pain with facet loading. Full, non-painful hip range of motion. Negative FABER, FADIR, and straight leg raise test bilaterally. DIFFERENTIAL DIAGNOSIS: 1. Discogenic pain 2. Facet-mediated pain 3. Disc herniation 4. Muscular strain 5. Sacroiliac joint dysfunction 6. Intrabdominal/ intrapelvic etiology 7. Neoplasm TESTS AND RESULTS: 1. Lumbar spine X-rays: -Normal alignment, normal vertebral body and disc space height -Partial lumbarization of S1 vertebral body -Five degrees of lumbar dextroscoliosis 2. MRI lumbar spine: -Lumbarization of S1 vertebral body -Normal disc heights and signal -Normal central canal and neural foramen size throughout lumbar spine -T1/T2 hyperintensity within S2 vertebral body, likely lipoma -Increased T2 signal medial to right kidney suggestive of hydronephrosis 3. Renal ultrasound:-Moderate right hydronephrosis with extrarenal pelvis. No nephrolithiasis. 4. Renogram with furosemide: - Right kidney with blunted flow and delayed clearance improved slightly with furosemide, consistent with partial obstruction at right ureteropelvic junction FINAL/WORKING DIAGNOSIS: Ureteropelvic junction obstruction causing Dietl’s crisis TREATMENT AND OUTCOMES: 1. Referral to urology 2. Resolution of pain and improvement in renal function after pyeloplasty

Analysis of changes in cervical spinal curvature and intervertebral disk space height following ACDF surgery in a group of 100 patients followed up for 12 months

We analysed 100 patients following anterior cervical discectomy and fusion with interbody stabilisation with PEEK cages. Radiographs obtained preoperatively and during the 12-month follow-up were compared to track changes in overall and local cervical lordosis and disk space height. Subsidence was defined as cage migration ≥ 3 mm into the adjacent endplates. Mean change in operated disk space height was 1.13 ± 1.33 mm. Subsidence was detected in 10.23% of the operated spaces. Mean change in overall cervical lordosis was 1.31 ± 5.71 degrees, and mean change in local lordosis was 0.19 ± 4.71 degrees. Change in overall cervical lordosis correlated with change in local lordosis (r = 0.61, p < 0.01). The greatest changes in lordosis and disk space height were noted immediately post-surgery. Baseline values were approximated gradually over time, but the post-operative values at 12 months were still higher than baseline. Disk space height change did not correlate with changes in patient-reported pain intensity at baseline (VAS 0) vs. at 12 months post-operatively (VAS 12) (r = 0.12, p < 0.05) or changes in the Neck Disability Index (NDI) at baseline (NDI 0) vs. at 12 months post-operatively (NDI 12) (r = −0.02, p = 0.05). Changes in overall cervical lordosis did not directly influence treatment outcomes assessed by comparing VAS 0 vs. VAS 12 (r = 0.13, p = 0.24) or NDI 0 vs. NDI 12 (r = −0.0005, p = 0.96). Surgical outcomes depend primarily on adequate decompression of the spinal cord and nerve roots. Post-operative radiological changes did not directly influence patients’ pain level or quality of life.

Degenerative changes of the thoracic spine do exist in patients with diffuse idiopathic skeletal hyperostosis: a detailed thoracic spine CT analysis.

Background Degenerative intervertebral disease (DID) is an exclusion criterion in the Resnick and Niwayama radiographic classification for diffuse idiopathic skeletal hyperostosis (DISH). However, although DID was previously described in DISH, no systematic computed tomography (CT) analysis has been reported so far. Purpose To assess for the presence and prevalence of such changes on CT examinations of the thoracic spine of individuals with DISH. Material and Methods Intervertebral space (D1-L1) on chest CT examinations of DISH patients was retrospectively evaluated for the presence of DID. Parameters evaluated were disc space height, disc protrusion, subchondral cysts/sclerosis, Schmorl nodes, vacuum phenomenon, and posterior elements including costovertebral and facet joints. Parameters were compared with two age- and gender-matched control groups of individuals whose entire spine CT lacked evidence of DISH (Control 1 individuals < 2 flowing osteophytes, Control 2 individuals < 4 and ≥ 2 flowing osteophytes). Results A total of 158 participants (DISH/Control 1/Control 2 = 54/54/50; 106 men, 52 women; average age = 70.6 years) were evaluated. Average intervertebral disc height was significantly lower in the DISH group compared with both control groups (DISH/Control 1/Control 2 = 4.55/5.13/5.01 mm, P < 0.001). Costovertebral degenerative changes were more prevalent in DISH patients ( P < 0.05) and, except for vacuum phenomenon (more prevalent in controls), other DID changes were as prevalent in DISH as in controls. Conclusion The presence of degenerative intervertebral changes on thoracic CT should not deter from diagnosing DISH. Thus, the radiographic Resnick and Niwayama DISH criteria cannot be directly adapted to CT.

Iatrogenic Spondylolisthesis Following Open Lumbar Laminectomy: Case Series and Review of the Literature.

To present diagnosis and surgical management of postlaminectomy spondylolisthesis in patients without preoperative instability and a review of relevant literature. Medical records and radiographic studies of 105 patients who underwent first-time bilateral 1- to 4-level open laminectomies for degenerative lumbar disease at a single academic institution were reviewed. Patients who initially presented with listhesis and had additional discectomy or fusion procedures were excluded. Of 105 patients with laminectomies across 1-4 levels, 10 patients (9.5%; 5 men and 5 women with average age of 63.0 ± 11.2 years) developed subsequent iatrogenic spondylolisthesis at the same operative levels that required reoperation. New or worsening low back pain and lower extremity pain were reported over an average period of 19.0 ± 17.5 months postoperatively. Imaging studies showed new spondylolisthesis that was not present before the index surgery, most commonly at L4-L5 level. All patients were treated surgically with posterior instrumented fusion. The average period between the first and second surgery was 32.6 ± 19.9 months. Surgical reduction of spondylolisthesis resulted in significant clinical improvement of patients' symptoms. In patients without overt pre-existing instability, laminectomy for lumbar stenosis can disrupt spinal stability and result in iatrogenic spondylolisthesis. The extent of decompression of the facet joints, number of levels decompressed, and preoperative disc space height can help assess the risk of postoperative spondylolisthesis. Patients who develop recurrent radiculopathy after decompressive lumbar laminectomy should be evaluated for potential iatrogenic spondylolisthesis.

Transforaminal Lumbar Interbody Fusion With Local Bone Graft Alone for Single-Level Isthmic Spondylolisthesis.

A retrospective study of patients treated by transforaminal lumbar interbody fusion (TLIF) with local bone graft alone for single-level isthmic spondylolisthesis (IS) between April 2009 and July 2014 in a single facility. Demographic and operative data, complications, preoperative and postoperative clinical records, and radiographs were revised. The Visual Analogue Scale (VAS) and Denis Work Scale were used for clinical and functional assessment. Modified Lee et al. classification was used for assessment of union. Twenty-three patients with mean age of 45.04 ± 7.19 years had single-level TLIF with local bone graft alone for symptomatic IS with mean follow-up period of 28.39 ± 4.01 months and mean operative time of 170.09 ± 11.22 minutes. The VAS and Denis Work Scale improved from 8.48 ± 0.58 and 4.67 ± 0.47 preoperative to 2.91 ± 1.25 and 1.33 ± 0.58 at the latest follow up, respectively. Anterior vertebral translation improved from 27.22 ± 9.54% preoperatively to 8.38 ± 3.63% postoperatively and 10.39 ± 3.49 at the latest follow up. Disc space height was 9.67 ± 5.55% preoperatively, 21.60 ± 4.11% postoperative, and 16.24 ± 4.02% at the latest follow up. Lumbar lordosis improved from 29.39 ± 10.33° to 45.13 ± 6.84° postoperatively and 39.96 ± 7.52° at the latest follow up. Eighteen patients had definitive union, 4 patients with possible union, 1 patient with possible pseudoarthrosis. Transforaminal lumbar interbody fusion with local bone graft alone is an appropriate option for single-level IS, yet we do not recommend it for higher grades of slippage with anterior vertebral translation more than 25%.

Retrospective Analysis of Arthrodesis from Various Options after Anterior Cervical Discectomy.

Introduction:Anterior cervical discectomy is a surgical procedure performed to treat a herniated/degenerated disc in the cervical region. There have been various studies comparing arthrodesis rates among various procedures. Our patients belonged to varied socioeconomic background and underwent anterior cervical microdiscectomy without/with instrumentation.Aim:The present study was performed to study and compare the arthrodesis rates in the patients operated for anterior cervical microdiscectomy with and without fusion/instrumentation procedures at our institution.Materials and Methods:This is a retrospective study performed at Vydehi Institute of Medical Sciences and Research Centre, Bengaluru. Pre- and post-operative X-rays were assessed in 96 patients who had undergone anterior cervical discectomy with/without fusion from June 2012 to June 2015. Radiographic arthrodesis was assessed in all patients. An arbitrary grading was designed by us and categorized into Grade I to IV. The criteria considered for adequate arthrodesis in this study were: (a) <2° movement on dynamic X-rays, (b) restored disc space height (±2 mm accepted), and (c) evidence of solid bone mass around disc space. Arthrodesis was categorized as Grade I if all the above 3 criteria on X-rays was fulfilled, Grade II if any 2 of the criteria was fulfilled, Grade III if any 1 of the criteria was fulfilled, and Grade IV when pseudoarthrosis/none of the criteria was fulfilled. Grade I arthrodesis was noted in about 79 patients (82.2%), Grade II in 14 patients, and only 3 patients had Grade III arthrodesis. There were no patients with absent arthrodesis/pseudoarthrosis.Results:Satisfactory arthrodesis was noted in 82% of the total patients, with patients undergoing fusion ± instrumentation procedure having better results.Conclusions:Arthrodesis by an interbody graft/implant with/without plating increases chances of success as compared to anterior cervical discectomy alone. Patients should be motivated for any of the available options for fusion/instrumentation

Early Outcomes of Anterior Cervical Discectomy and Fusion Using a Porous PEEK Interbody Fusion Device

Background: Recently, porous surface polyether-etherketone (PEEK) implants have been developed to interact with adjacent endplates. Our goal was to evaluate the efficacy of novel high-strength, porous PEEK interbody fusion devices for anterior cervical discectomy and fusion (ACDF) in patients with symptomatic single-level and multilevel degenerative cervical disc disease at 1 year. Methods: Fifty consecutive patients (31 women, 19 men; average age, 60 years) with degenerative cervical disc disease underwent ACDF using a porous PEEK interbody implant and plate. There were 11 1-level; 23 2-level, and 16 3-level fusions between C3 and C7. Patients were assessed at 1.5, 3, 6, and 12 months. Standardized outcome measures were used to evaluate the patient’s condition before and after surgery. Plain radiographs were used to assess fusion, bony in-growth, subsidence, and implant migration. Sagittal plane angulation was measured on neutral lateral radiographs and determined by Cobb’s criteria. Intradiscal distraction and subsidence were measured by assessing the vertical distance between the midpoints of the adjacent vertebral endplates. Results: At 12 months after surgery, all patients showed improvement in Oswestry Neck Disability Index and neck and arm pain scores. Similarly, at 12 months, all patients showed radiographic fusion. No patient demonstrated motion across the interspace on flexion-extension lateral radiographs. Sagittal plane angulation improved to an average of -6° (range, -2° to -8°) with no measurable evidence of implant migration or subsidence. Average disc space height increased more than 4 mm. No patient had measurable radiographic evidence of a pseudarthrosis or halo formation around the implant. Conclusion: One-year results in this prospective nonrandomized study show that porous-surface PEEK is a clinically viable alternative for improving osseointegration and fusion rates of interbody implants to treat degenerative cervical disc disease.

Bioabsorbable self-retaining PLA/nano-sized β-TCP cervical spine interbody fusion cage in goat models: an in vivo study.

Study designThis is an experimental animal study.ObjectiveThe objective of this study was to compare an anterior cervical discectomy and interbody fusion of a novel polylactide/nano-sized β-tricalcium phosphate (PLA/nβ-TCP) bioabsorbable self-retaining cervical fusion cage (BCFC) with an autologous bone graft and polyetheretherketone (PEEK) cages.BackgroundAlthough PLA cervical cages have potential advantages compared with traditional materials, they are not currently routinely used in spine surgery because of undesirable effects such as the lack of osteoconductivity and osteolysis around the implant. This study involved the manufacturing of a bioabsorbable cage from PLA/nβ-TCP that was then used as a device for anterior cervical discectomy and fusion (ACDF) on a goat cervical spine fusion model.Materials and methodsEighteen goats underwent C3/C4 discectomy and were randomly divided into three groups based on the following methods: Group A (n=6), an autologous bone graft; Group B (n=6), PEEK cage filled with an autologous graft; and Group C (n=6), BCFC filled with an autologous iliac bone. Radiography was performed preoperatively and postoperatively and at 1, 4, 8, and 12 weeks after the operation. Disc space height (DSH) was measured at the same time. After 12 weeks, the fused segments were harvested and evaluated with functional radiographic views, biomechanical testing, and histological analyses.ResultsOver a 12-week period, the BCFC and PEEK cage groups exhibited significantly higher DSH values than the bone graft group. Additionally, the BCFC group yielded a significantly lower range of motion in axial rotation than both the autologous bone graft and PEEK cage groups. A histologic evaluation revealed an increased intervertebral bone volume/total volume ratio and better interbody fusion in the BCFC group than in the other groups.ConclusionThe BCFC device exhibited better results than the autologous bone graft and PEEK cages in single-level ACDF models in vivo. This device may be a potential alternative to the current PEEK cages.

Cage Retropulsion after Posterior Lumbar Interbody Fusion by Unilateral stand-alone Carbon Cage

Background Data: Posterior lumbar interbody fusion (PLIF) becomes widely used surgical procedure to reduce pain and spinal instability resulting from some spinal diseases. Although this procedure is widely used, postoperative conditions such as good clinical outcome and spinal instability are still a matter of controversy. Maintenance of disc height and solid fusion significantly increased with PLIF with cage. Cage migration to the spinal canal is one of the most common cause of implant failure in mono-segmental lumbar interbody fusion.Purpose: to evaluate the efficacy of unilateral stand-alone carbon cage in patients with degenerated lumbar disc diseaseStudy Design: A prospective follow-up study.Patients and Methods: A prospective follow-up study was carried out on 40 patients (24 males and 16 females). All patients had single level lumbar disc prolapse, diagnosed clinically and radiologically, who admitted to Neurosurgery Department, Mansoura University Hospital and on Private work during the period from March 2013 to March 2015. On admission demographic data as age, gender, job and body mass index (BMI) were obtained for all patients. All patients were examined on admission clinically and radiologically by MRI lumbosacral spine and dynamic study plain x-ray films in extension and flexion views. Disc height was measured for all patients at the herniated level only, by MRI using Dabbs method. The outcome was measured according to modified Mac-Nab’s criteria.Results: Six cases out of 40 (15%) developed cage retropulsion. There was a lower significant mean age (38.3+2.96) for cases with cage retropulsion compared to (42.4+5.7) for those cases without cage retropulsion (P 0.05). The majority of cases with cage retropulsion were obese (66.7%), while those without cage retropulsion were overweight (64.7%). L4-5 was the most common affected level (66.6%) among cases with cage retropulsion, and those without retropulsion were (70.6%). The majority of cases (5) with cage retropulsion (83.3%) had wide disc space height. Workers and carriers represented the majority of cases with cage retropulsion (33.3%). All cases (100%) with cage retropulsion had a poor outcome. However, the majority of cases with no cage retropulsion had excellent (50%) and good (11.8%) outcome according to the modified Mac-Nab’s criteria.Conclusion: Our data suggest that strenuous work, early heavy physical activities, large disc height may be contributing factors for cage retropulsion. Cage retropulsion has a negative impact on patients’ outcome. (2017ESJ146)

How to choose when implants of adjacent height both fit the disc space properly in single-level cervical artificial disc replacement.

In cervical artificial disc replacement (C-ADR), sometimes we encountered with such cases that implants of adjacent height both fit the target disc space properly. No study was available discussing the choice of implant height and the clinical outcomes under such circumstance. The purpose of this study was to evaluate the impact of different implant heights on the clinical outcomes and radiographic results when the implants of adjacent height both fit the disc space properly. This retrospective study included 34 patients underwent single-level C-ADR at the C5–C6 level at our institution. In these 34 patients, implant with either 5 mm height or 6 mm height fit the surgical level properly without overstretching the disc space or the facet joint space. Clinical outcomes were evaluated using the Japanese Orthopedic Association score, visual analog scale (VAS), and Neck Disability Index. Radiographic assessments were conducted on static and dynamic radiographs for the determination of the disc space height, intersegmental range of motion (ROM), and the ROM of the functional spinal unit (FSU) at the surgical level. The baseline information of the patients, such as age, gender, weight, follow-up time, and diagnosis, was similar between the 2 groups (P > .05). Postoperative mean VAS in group B was significantly lower than that in group A (2.1 ± 0.7 vs. 2.7 ± 1.0, P < .05). The mean VAS decrease in group B was significantly larger than that in group A (5.3 ± 0.8 vs. 4.6 ± 1.1, P < .05). Significant difference was found in the postoperative disc height of the surgical segment between the 2 groups (6.4 ± 0.4 mm vs. 7.5 ± 0.5 mm, P < .05). No significant differences were noted in the intersegmental ROM and ROM of the FSU between the 2 groups both before the surgery and at the last follow-up (P > .05). No hypermobility or instability was observed in these patients. Our results suggested that when implants of adjacent height both fit the disc space properly, using the larger implant could result in better pain relief without the risk of segmental hypermobility in patients underwent single-level C-ADR at the C5–C6 level.

Effect of Modic Changes in Cervical Degenerative Disease.

ObjectiveModic changes are signal intensity changes in adjacent vertebral bone marrow on magnetic resonance imaging. Few studies have investigated these changes with regard to the cervical spine. In this study, we investigated the associations between cervical degenerative disease and Modic changes.MethodsWe conducted a retrospective collection of radiological data in patients with neck pain at Pusan National University Yangsan Hospital from January 2010 to December 2014. A total of 169 patients were included in this study. Disc herniation grade, disc space height and global cervical lordosis (C2–C7 Cobb angle) were measured and analyzed. If Modic changes were present, we recorded the Modic change type based on the literature, vertebral level, age, sex, and surgical requirement.ResultsSixty-six patients exhibited Modic changes in the cervical spine. Out of these 66 patients, Modic change type II (56 patients, 84.8%) and C5–6 vertebral level (23 patients, 34.8%) were the most predominant categories. Patients with Modic change showed worse outcomes in regard to disc herniation grade, disc space height and global cervical lordosis than patients without (p<0.01). Among 169 patients, 18 patients had undergone anterior cervical discectomy with fusion (ACDF). Patients with Modic changes (10 of 66 patients, 15.1%) had a greater probability of undergoing ACDF than those without (8 of 103 patients, 7.8%; p<0.01).ConclusionModic changes refer cervical degenerative changes, and incidence of ACDF is higher when the Modic changes are occurred.

Case control study on two different surgical approaches combined fixation with lumbar interbody fusion for the treatment of single segmental lumbar vertebra diseases

To discuss the advantages and disadvantages of two different surgical approaches combined fixation with lumbar interbody fusion in treating single segmental lumbar vertebra diseases. The clinical data of 86 patients with single segmental lumbar vertebra diseases treated from June 2011 to June 2013 was retrospectively analyzed. There were 33 males and 53 females, aged from 28 to 76 years old with an average of 53.0 years. Among them, there were 39 cases of lumbar disc degeneration, 22 cases of lumbar disc herniation complicated with spinal canal stenosis, 9 cases of huge lumbar disc herniation and 16 cases of lumbar degenerative spondylolisthesis (Meyerding degree I ). Lesion sites contained L3, 4 in 5 cases, L4, 5 in 70 cases and L5S1 in 11 cases. All the patients were treated with internal fixation and lumbar interbody fusion with 45 cases by midline incision approach (median incision group) and the other 41 cases by channel-assisted by muscle-splitting approach(channel group). Incision length, operation time, intraoperative bleeding and postoperative drainage were recorded in two groups. Visual analogue scale(VAS) was used to assess lumbar incision pain 72 h after operation. Depended on imaging results to compare the changes of the disc space height in lesion in preoperative, postoperative and final follow-up, the coronal and sagittal Cobb angle in preoperative and final follow-up, the area of multifidus and the degree of multifidus fat deposition before and after operation between two groups. Loosening or fragmentation of internal fixation, displacement of intervertebral cage and interbody fusion were observed in each group. Japanese Orthopedic Association (JOA) scoring system was used to evaluate the function before operation and at the final follow-up. The channel group was superior to the median incision group in incision length and postoperative drainage while the median incision group was less than the channel group in the operation time and intraoperative bleeding. The average VAS score of lumbar incision 72 h after operation was 1.50 points in median incision group and 0.97 points in channel group, and there was significant difference between two groups(P<0.05). No incision infection was found, but there were 4 cases of incisional epidermal necrosis, 1 case of incision healed badness, and 3 cases of nerve injury in channel group. The incidence of cacothesis of pedicle screw were 5.0% and 3.6% in median incision group and channel group respectively, and there was no significant difference between two groups(P>0.05). The incidence of cacothesis of translaminar facet screw were 6.6% and 12.2% in median incision group and channel group respectively, and there was significant difference between two groups(P<0.05). All the patients were followed up for 12 to 36 months with a mean of 22.8 months. The changes of disc space height had statistical difference between preoperative and postoperative(P<0.05) in all patients, but there was no significant difference between postoperative and final follow-up(P>0.05), however, there was no significant difference 3 days after operation and final follow-up between two groups(P>0.05). At final follow-up, coronal and sagittal Cobb angle were obviously improved in all patients(P<0.05), but there was no significant difference between two groups(P>0.05). One year after operation, the area of multifidus in median incision group was (789.00±143.15) mm² less than preoperative(1 066.00±173.55) mm² (P<0.05), and in channel group, was(992.00±156.75) mm² at 1 year after operation and(1 063.00±172.13) mm² preoperatively, there was no significant difference between them(P>0.05), however, there was significant difference one year after operation between two groups (P<0.05) . About the degree of multifidus fat deposition, there was significant difference between one year after operation and preoperation in median incision group (P<0.05), but there was no significant difference between one year after operation and preoperation in channel group (P>0.05), and there was significant difference at one year after operation between two groups(P<0.05). During the follow-up period, neither pedicle screw and/or translaminar facet screw loosening, displacement or fragmentation nor displacement of intervertebral cage were found. The lumbar interbody fusion rate was 95.6% in median incision group and was 95.1% in channel group, and there was no significant difference between two groups(P>0.05). No obvious adjacent segmental degeneration was observed in fixed position. JOA score in median incision group was significantly increased from 8-16 points (average: 12.77±2.56) preoperative to 21-29 points (average: 25.20±2.43) at final follow-up(P<0.05); and in channel group was significantly increased from 8-16 points (average: 12.64±2.37) preoperative to 23-29 points(average: 26.7±1.82) at final follow-up(P<0.05); there was also significant difference between two groups at final follow-up. Compared to the median incision approach, unilateral pedicle screw combined with contralateral translaminar facet screw fixation using channel-assisted by muscle-splitting approach has advantages of small incision, less trauma, fast recovery and so on. However, it also has shortages such as high surgical complications incidence, especially in cases that.

Clinical and radiographic outcomes of bilateral decompression via a unilateral approach with transforaminal lumbar interbody fusion for degenerative lumbar spondylolisthesis with stenosis

Background ContextLaminectomy with posterior lumbar interbody fusion (PLIF) has been shown to achieve satisfactory clinical outcomes, but it leads to potential adverse consequences associated with extensive disruption of posterior bony and soft tissue structures. PurposeThis study aimed to compare the clinical and radiographic outcomes of bilateral decompression via a unilateral approach (BDUA) with transforaminal lumbar interbody fusion (TLIF) and laminectomy with PLIF in the treatment of degenerative lumbar spondylolisthesis (DLS) with stenosis. Study DesignThis is a prospective cohort study. Patient SampleThis study compared 43 patients undergoing BDUA+TLIF and 40 patients undergoing laminectomy+PLIF. Outcome MeasuresVisual analog scale (VAS) for low back pain and leg pain, Oswestry Disability Index (ODI), and Zurich Claudication Questionnaire (ZCQ) score. MethodsThe clinical outcomes were assessed, and intraoperative data and complications were collected. Radiographic outcomes included slippage of the vertebra, disc space height, segmental lordosis, and final fusion rate. This study was supported by a grant from The National Natural Science Foundation of China (81572168). ResultsThere were significant improvements in clinical and radiographic outcomes from before surgery to 3 months and 2 years after surgery within each group. Analysis of leg pain VAS and ZCQ scores showed no significant differences in improvement between groups at either follow-up. The mean improvements in low back pain VAS and ODI scores were significantly greater in the BDUA+TLIF group than in the laminectomy+PLIF group. No significant difference was found in the final fusion rate at 2-year follow-up. The BDUA+TLIF group had significantly less blood loss, shorter length of postoperative hospital stay, and lower complication rate compared with the laminectomy+PLIF group. ConclusionsWhen compared with the conventional laminectomy+PLIF procedure, the BDUA+TLIF procedure achieves similar and satisfactory effects of decompression and fusion for DLS with stenosis. The BDUA+TLIF procedure appears to be associated with less postoperative low back discomfort and quicker recovery.

Evaluation of Bioabsorbable Multiamino Acid Copolymer/Nanohydroxyapatite/Calcium Sulfate Cage in a Goat Spine Model.

Currently, polylactide is the most popular material used to made bioabsorbable cages but too-quick degradation and osteolysis around the cage have been reported in the literature. This study evaluated the fusion effect, biomechanical stability, and histologic characteristics of a novel bioabsorbable multiamino acid copolymer/nanohydroxyapatite/calcium sulfate (MAACP/n-HA/CS) interbody cage in a goat model of anterior cervical discectomy and fusion. A total of 24 goats underwent C3/C4 discectomy and fusion with 3 groups of intervertebral implants: MAACP/n-HA/CS cage group (n= 8), titanium cage group (n= 8), and autologous tricortical iliac crest bone group (n= 8). Disc space height and lordosis angle were measured pre- and postoperatively and after 4, 12, and 24 weeks. Range of motion (ROM) was evaluated through biomechanical testing. Histologic analysis was performed to evaluate fusion status and to detect any foreign body reactions associated with the bioabsorbable cages. At 12 and 24 weeks, disc space height in MAACP/n-HA/CS cage group was greater than that of titanium cage group and tricortical iliac crest group (P < 0.05). Lordosis angle in MAACP/n-HA/CS cage group and titanium cage group were lower than that of tricortical iliac crest group (P < 0.05). Biomechanical test showed that ROM did not differ significantly between MAACP/n-HA/CS cage group and titanium cage group, whereas the value of ROM in bone graft group was the largest. Histologic evaluation showed a better interbody fusion in the MAACP/n-HA/CS cage group than in the other 2 groups. MAACP/n-HA/CS cage surface degraded and was absorbed at 24 weeks. All MAACP/n-HA/CS cages showed excellent biocompatibility. MAACP/n-HA/CS cages can provide good fusion effect, enough biomechanical stability, and integrate closely with the surrounding bone.

A comparison of local bone graft with PEEK cage versus iliac bone graft used in anterior cervical discectomy and fusion

ObjectiveAnterior cervical discectomy and fusion (ACDF) is a popular procedure for patients with cervical spondylotic myelopathy, but few studies reported the clinical outcomes of cervical local bone graft with a PEEK cage used in it. This retrospective study was performed to compare the clinical and radiological outcomes of using local bone graft with a PEEK cage versus iliac bone graft in ACDF. Patients and methodsA total of 60 consecutive patients who underwent ACDF were evaluated from January 2010 to January 2013. Twenty-nine patients received ACDF with a PEEK cage combined with cervical local bone graft (local bone group) and 31 patients received ACDF with autologous tricortical iliac bone graft (iliac bone group). The intraoperative and perioperative complications of both groups were recorded. Preoperative and postoperative radiographs were taken to calculate the ratio of interbody height to the disc height and the interbody bony fusion rate. The Japanese Orthopedic Association (JOA) score and visual analogue scale (VAS) were used to estimate postoperative clinical outcomes. ResultsThe mean follow-up duration was 25.0±3.8months in the local bone group and 24.4±3.4months in the iliac bone group (P=0.56). Although there was no significant difference between the two groups in terms of blood loss (P=0.17), the length of surgery was significantly less in the local bone group comparing with that of iliac bone group (P=0.01). Postoperatively, VAS scores were significantly decreased, and JOA scores were improved in both groups. However, no statistically significant differences were found between the two groups at final follow up (P=0.45 and P=0.93). The disc space height and segmental interbody angle at the surgical segment were greater in local bone group than those in the iliac bone group (P<0.001 and P<0.001). The fusion rates were 93.1% in local bone group and 90.3% in the iliac bone group at last follow up (P=0.70). Perioperative complication rates in local bone group and iliac bone groups were 6.8% and 29%, respectively (P=0.04). ConclusionsBased on this study, patients receiving ACDF with local bone graft combined with a PEEK cage had significant shorter operation time, lower perioperative complications rate, and better radiological results comparing with those with an iliac bone graft alone. It seems that the local bone graft with a PEEK cage appears to be a safe alternative to the iliac bone graft for ACDF.

Comparison Between Acrylic Cage and Polyetheretherketone (PEEK) Cage in Single-level Anterior Cervical Discectomy and Fusion: A Randomized Clinical Trial.

Prospective, single-blind randomized-controlled clinical study. To compare polyetheretherketone (PEEK) cage with a novel Acrylic cage to find out which fusion cage yielded better clinical outcomes following single-level anterior cervical discectomy and fusion (ACDF). ACDF is considered a standard neurosurgical treatment for degenerative diseases of cervical intervertebral disks. There are many options, including bone grafts, bone cement, and spacers made of titanium, carbon fiber, and synthetic materials, used to restore physiological disk height and enhance spinal fusion, but the ideal device, which would provide immediate structural support and subsequent osteointegration and stability, has not been identified yet. To overcome this, we designed a new, inexpensive Acrylic cage. A total of 64 patients were eligible to participate and were randomly allocated to undergo ACDF either with Acrylic interbody fusion cage filled with bone substitute (n=32) or PEEK cage (n=32). Nurick's grading was used for quantifying the neurological deficit. Clinical and radiologic outcome was assessed preoperatively, immediately after surgery, and subsequently at 2, 6, and 12 months of follow-up using Odom's criteria and dynamic radiographs (flexion-extension) and computed tomography scans, respectively. There was a statistically significant improvement in the clinical outcomes of the Acrylic cage group compared with the PEEK cage group (mean difference: -0.438; 95% confidence interval, -0.807 to -0.068; P=0.016). There was a statistically significant difference in disk space height increase between the 2 groups at the 6- and 12-month follow-up. The Acrylic cage achieved higher fusion rate (good fusion) than the PEEK cage (96.9% vs. 93.8%). Intervertebral angle demonstrated a significant difference among the 2 treated groups throughout the follow-up period. This study suggests that the use of Acrylic cage is associated with good clinical and radiologic outcomes and it can be therefore a good substitute for bone graft and other cages in ACDF.

Unilaterally posterior lumbar interbody fusion with double expandable peek cages without pedicle screw support for lumbar disc herniation

ObjectivesPosterior lumbar interbody fusion (PLIF) is usually bilateral procedure, and it is combined with posterior by bilateral pedicle screw support or with fixation. The purpose of this retrospective study was to compare the surgical outcomes of simple discectomy and PLIF without pedicle screw support in patients with lumbar disc herniation (LDH). Patients and methods60 patients with single segment LDH were operated between February 2010 and June 2013. 40 patients were treated with simple discectomy (Group 1) and 20 patients were treated with PLIF using double expandable polyetheretherketone (PEEK) cages without instrumentation (Group 2) unilaterally. Pain and function were evaluated by the visual analog scale (VAS) and Oswestry disability index (ODI) before and 18 months after surgery. Besides, PLIF patients were evaluated with computerized tomography (CT) scan of lumbar vertebra for the evaluation of the height of the disc, instability and fusion. ResultsBoth leg and low back pain VAS scores were significantly improved 18 months after surgery in both of the groups (p<0.001). Significant decrease in VAS low back pain scores was seen in group 2 when compared to group 1 (p<0.001). Height of the intervertebral disc space was preserved and no instability was detected in group 2. No recurrence and 80% fusion rate was achieved in group 2. ConclusionThis study showed that unilateral PLIF intervention with double expandable PEEK cages without pedicle screw support would be sufficient in the management of single segment lumbar disc herniation in patients whom are thought to have lumbar stabilization.