Tandem age-related lumbar and cervical intervertebral disc changes in asymptomatic subjects

Purpose

To investigate the frequency of tandem lumbar and cervical intervertebral disc degeneration in asymptomatic subjects.

Methods

We evaluated magnetic resonance imaging (MRI) results from 94 volunteers (48 men and 46 women; mean age 48 years) for age-related intervertebral disc degeneration in the lumbar and cervical spine.

Results

MRI indicated degenerative changes in the lumbar spine in 79 subjects (84 %), with decreased disc signal intensity in 74.5 %, posterior disc protrusion in 78.7 %, anterior compression of the dura in 81.9 %, disc space narrowing in 21.3 %, and spinal canal stenosis in 12.8 %. These findings were more common in older subjects at caudal levels. MRI showed degenerative changes in both the lumbar and cervical spine in 78.7 % of the volunteers.

Conclusions

Degenerative findings in both the lumbar and cervical spine, suggesting tandem disc degeneration, was common in asymptomatic subjects. These results provide normative data for evaluating patients with degenerative lumbar and cervical disc diseases.     

Using notochordal cells of developmental origin to stimulate nucleus pulposus cells and bone marrow stromal cells for intervertebral disc regeneration

Purpose

Bone marrow stromal cells (BMSCs) have been proposed to complement the declining population of nucleus pulposus cells (NPCs) found in a degenerative intervertebral disc. Although able to stop degeneration, they could not produce enough matrix to restore a healthy state. Looking at development, when a large amount of matrix is produced, the disc also contains notochordal cells (NCs), potential progenitors or regulators of NPCs. The aim of the study was, therefore, to combine NCs to a BMSC/NPC mix and evaluate their effects on cell phenotype and matrix production, in long-term culture.

Methods

In a 3D hydrogel, NCs were co-cultured in different ratios with BMSCs and/or NPCs. Matrix production, cell morphology, and gene expression of disc markers were assessed after 4 weeks of culture.

Results

At day 28, BMSCs/NPCs highly expressed disc matrix markers (type II collagen and aggrecan) and produced disc matrix up to 30 % of values obtained for the positive control (BMSCs under TGFβ stimulation). The addition of NCs only slightly up-regulated marker expression (6–12× increase); an up-regulation not reflected at the matrix level. During the 4 weeks of culture, however, the NC phenotype changed drastically (morphology, disc marker expression).

Conclusion

In contrast to previously reported short-term studies, long-term co-cultures with NCs had no substantial effects on BMSCs and NPCs, most likely due to the loss of the NC native phenotype during culture. It, therefore, appears critical to maintain this specific phenotype for a long-term effect of the NCs.     

An increase in height of spinous process is associated with decreased heights of intervertebral disc and vertebral body in the degenerative process of lumbar spine

Purpose

Currently degeneration of the intervertebral disc and joint in the degenerative process of the lumbar spine has mainly attracted the attention, however, there are very few literatures focusing on the height of the spinous process. Our objective was to examine in what generation the change in spinous process height occurs and how the change is involved in the degenerative process of the lumbar spine.

Methods

CT or CT myelography of 1,015 patients, 536 males and 579 females were measured in 6 items, including the heights of the L4 and L5 vertebral bodies, the L4 and L5 spinous processes, the L4/5 intervertebral disc, and the L5/S1 intervertebral disc. All data of the 6 items were analyzed and compared between gender in 5 age groups (40s, 50s, 60s, 70s and 80s).

Results

The results indicated a significant increase in the height of the L4 and L5 spinous process (P < 0.01) in the 60- to 70-year-old group for both genders, and also showed that the L4 and L5 vertebral body height was significantly decreased in the 50- to 60-year-old group (P < 0.01 in males, P < 0.001 in females).

Conclusions

Changes in the spinous process morphology followed degenerative changes of the intervertebral disc and vertebral body in the degenerative process of the lumbar spine. This result may suggest that the morphological change of an increase in the height of the spinous process may be a kind of biological defense reaction to stabilize the intervertebral portion.     

Heme oxygenase-1 modulates degeneration of the intervertebral disc after puncture in Bach 1 deficient mice

Purpose

Intervertebral disc degeneration is considered to be a major feature of low back pain. Furthermore, oxidative stress has been shown to be an important factor in degenerative diseases such as osteoarthritis and is considered a cause of intervertebral disc degeneration. The purpose of this study was to clarify the correlation between oxidative stress and intervertebral disc degeneration using Broad complex-Tramtrack-Bric-a-brac and cap‘n’collar homology 1 deficient (Bach 1?/?) mice which highly express heme oxygenase-1 (HO-1). HO-1 protects cells from oxidative stress.

Methods

Caudal discs of 12-week-old and 1-year-old mice were evaluated as age-related models. Each group and period, 5 mice (a total of 20 mice, a total of 20 discs) were evaluated as age-related model. C9–C10 caudal discs in 12-week-old Bach 1?/? and wild-type mice were punctured using a 29-gauge needle as annulus puncture model. Each group and period, 5 mice (a total of 60 mice, a total of 60 discs) were evaluated. The progress of disc degeneration was evaluated at pre-puncture, 1, 2, 4, 8 and 12?weeks post-puncture. Radiographic, histologic and immunohistologic analysis were performed to compare between Bach 1?/? and wild-type mice.

Results

In the age-related model, there were no significant differences between Bach 1?/? and wild-type mice radiologically and histologically. However, in the annulus puncture model, histological scoring revealed significant difference at 8 and 12?weeks post-puncture. The number of HO-1 positive cells was significantly greater in Bach 1?/? mice at every period. The apoptosis rate was significantly lower at 1 and 2?weeks post-puncture in Bach 1?/? mice.

Conclusions

Oxidative stress prevention may avoid the degenerative process of the intervertebral disc after puncture, reducing the number of apoptosis cells. High HO-1 expression may also inhibit oxidative stress and delay the process of intervertebral disc degeneration.     

Mechanical stress-induced apoptosis of nucleus pulposus cells: an in vitro and in vivo rat model

Background

Un-physiological loads play an important role in the degenerative process of inter-vertebral discs (IVD). In this study, we used an in vitro and in vivo rat model to investigate the mechanism of nucleus pulposus (NP) cells apoptosis induced by mechanical stress.

Methods

Static compressive load to IVDs of rat tails was used as the in vivo model. For the in vitro model, NP cells were tested under the physiological and un-physiological loading. For histological examination, apoptotic index study, and apoptotic gene expression, we also selected cytokines [bone morphogenetic protein (BMP)-2/7, insulin-like growth factor (IGF)-1, platelet-derived growth factor (PDGF)] to be analyzed.

Results

Under mechanical loading, cellular density was significantly decreased, but there was an increase of TUNEL positive cells and apoptosis index. In a dose-dependent manner; the necrosis became apparent in the un-physiologic strain. The selected cytokines (BMP-2/7, IGF-1, PDGF) can significantly reduce the percentage of apoptotic and necrotic cells.

Conclusions

We conclude that the intrinsic (mitochondrial) apoptotic pathway plays an important role in the compressive load-induced apoptosis of NP cells. Combination therapy reducing the mechanical load and selected cytokines (BMP-2/7, IGF-1 and PDGF) may have considerable promise in the treatment of spine disc degeneration.     

Dose- and time-dependent effect of high glucose concentration on viability of notochordal cells and expression of matrix degrading and fibrotic enzymes

Purpose

Diabetes mellitus is an important aetiological factor in intervertebral disc degeneration. The disappearance of notochordal cells in the nucleus pulposus is thought to be the starting point for intervertebral disc degeneration. A cellular effect of diabetes mellitus on apoptosis of notochordal cells and intervertebral disc degeneration has been recently reported. However, how the duration and severity of diabetes mellitus affects viability of notochordal cells and intervertebral disc degeneration is still unknown .

Methods

Rat notochordal cells were isolated, cultured, and placed in either 10 % foetal bovine serum (FBS) (normal control) or 10 % FBS plus three different high glucose concentrations (0.1 M, 0.2 M, and 0.4 M) (experimental conditions) for one, three, five and seven days, respectively. We identified and quantified the degree of proliferation and apoptosis, caspase activities, and cleavages of Bid and cytochrome-c. In addition, we examined the cells for expression of matrix metalloproteinases (MMPs) and their tissue inhibitors of metalloproteinases (TIMPs).

Results

Each three high glucose concentrations significantly decreased proliferation and increased apoptosis of notochordal cells from culture days one to seven in a dose-dependent manner. Compared with those of 10 % FBS, caspase-9 and -3 activities and cleavage of Bid and cytochrome-c were significantly increased in each three high glucose concentrations, accompanied by increased expression of MMP-1, -2, -3, -7, -9, and -13 and TIMP-1 and -2.

Conclusions

High glucose concentration significantly decreased proliferation and increased apoptosis of notochordal cells via the intrinsic pathway with dose- and time-dependent effects. We also found that expression of MMPs and TIMPs was increased with dose- and time-dependent effects. Therefore, these results suggest that aggressive glucose control from an early stage of diabetes mellitus should be recommended to prevent or limit intervertebral disc degeneration.     

LUCL-Bandplastik mit Trizepssehnentransplantat zur Therapie der posterolateralen Rotationsinstabilität am Ellenbogen

Objective

Re-establishment of radial stability within the elbow joint in cases of arthroscopically or clinically confirmed posterolateral rotatory instability.

Indications

Posttraumatic or chronic degenerative posterolateral rotatory instability at least grade I–II according to O’Driscoll.

Contraindications

Elbow stiffness or elbow arthritis and lateral epicondylitis, if a posterolateral rotatory instability has been excluded as the reason for the symptoms.

Surgical technique

Reconstruction or augmentation of the insufficient lateral ulnar collateral ligament (LUCL) with an autologous triceps tendon graft. A stripe of the triceps tendon is fixed at the epicondylus humeri radialis and at the base of the annular ligament at the proximal radial ulna with tenodesis screws or buttons, then the extensor origins, which were detached before are fixated as well.

Postoperative management

Postoperative treatment with an elbow orthesis for 6 weeks, in the first 4 weeks limitation of complete extension and flexion, full weight bearing after 3 months.

Results

Retrospective analysis of 47 LUCL reconstructions from 2008–2010 with good results concerning pain reduction and acceptance, improvement of the Mayo Elbow Performance Score from 49 to 82, low complication rate with one elbow stiffness, one temporary ulnar nerve lesion, and one recurrent instability.     

The protective role of dynamic stabilization on the adjacent disc to a rigid instrumented level. An in vitro biomechanical analysis

Objectives

To assess the changes of intradiscal pressure at the bridged and at the adjacent levels to a lumbar two-level hybrid instrumentation.

Introduction

The elimination of motion produced by spinal fusion may have potential consequences beyond the index level overloading the juxtaposed spinal motion segments and leading to the appearance of degenerative changes. Degeneration of the segments adjacent to instrumented levels has become a topic of increasing interest in the literature over the last years. In order to prevent degenerative disc changes at the adjacent segments to a fused level, a broad scope of techniques have been developed, one of them is hybrid constructs.

Methods

In 6 human cadaveric lumbosacral specimens, pressure transducers quantified intradiscal pressure changes at three levels (L3–L4, L4–L5 and L5–S1) under axial compression (0–750 N), anterior flexion (+12°) and extension (?12°) in three different situations of spinal stability: intact, L5–S1 rigid rod pedicle screw instrumentation and L4–S1 two-level hybrid instrumentation (rigid at L5–S1 and dynamic at L4–L5).

Results

Once the L5–S1 segment had implanted the rigid instrumentation system (Diapason), the intradiscal pressure at this level decreased by 65 % while the intradiscal pressure at the disc above (L4–L5) increased 20 %. After augmenting the L5–S1 posterior construct with a dynamic stabilization device (Dynesys) at the superior adjacent level, the intradiscal pressure at this level, L4–L5, decreased by 50 % whereas intradiscal pressure at its adjacent level, L3–L4, only experienced a slight increase of 10 %.

Conclusions

The raise of intradiscal pressure at the adjacent segment to a rigid instrumented segment can be reduced when the rigid construct is augmented with a dynamic stabilization device. Hybrid constructs might have a possible protecting role preventing the occurrence of degenerative disc changes at the adjacent segment to a rigid instrumented level. Augmentation with a dynamic stabilization device might protect the disc above a rigid rod pedicle screw construct.     

An analysis of fusion cage migration in unilateral and bilateral fixation with transforaminal lumbar interbody fusion

Purpose

To investigate if instrumentation (unilateral vs. bilateral fixation) has an effect on the rate of fusion cage migration.

Methods

This clinical study of transforaminal lumbar interbody fusion involved a prospective group of 116 patients who were randomly assigned to either unilateral (n = 57) or bilateral (n = 59) fixation. Fourteen were lost to follow-up (11 from the unilateral group and 3 from the bilateral group).

Results

The unilateral fixation group consisted of 20 male and 26 female patients. In the unilateral group, the mean age was 53.5 years (range, 18–77), and the preoperative diagnosis consisted of degenerative disc disease, with or without herniated disc (n = 44), and degenerative spondylolisthesis with spinal stenosis (n = 2). The bilateral fixation group consisted of 20 male and 36 female patients. In the bilateral group, the mean age was 55.7 years (range, 26–82), and the preoperative diagnosis consisted of degenerative disc disease, with or without herniated disc (n = 40), and degenerative spondylolisthesis with spinal stenosis (n = 16). A total of 17 cases of cage migration were found; of these, 11 were from the unilateral group and 6 from the bilateral group, resulting in rates of cage migration of 23 and 11 % (p = 0.03), respectively. In regard to migration cases, 5 were male and 12 were female. Ages ranged from 27 to 79 years (mean age, 55 years).

Conclusion

We conclude that unilateral fixation is not stable enough to prevent fusion cage migration in some patients who undergo TLIF.     

“Sliding angulation osteotomy”: preliminary report of a novel technique of treatment for chronic radial head dislocation following missed Monteggia injuries

Purpose

Neglected anterior radial head dislocation in type I Monteggia lesions leads to restriction of movement, deformity and instability of the affected elbow. If left untreated this leads to a painful arthritic elbow due to secondary degenerative changes. This is a difficult problem to manage and many intra-articular, extra-articular and combined procedures have been described with variable results. We report a new technique of sliding angulation osteotomy for this condition, which allows both lengthening and angulation of the ulna.

Methods

A novel technique of sliding angulation osteotomy of the proximal ulna was done to achieve reduction of the radial head. Four patients with persistent anterior radial head dislocation were treated at our institution with this technique.

Results

All of them had good clinical and radiological outcomes at final follow-up.

Conclusions

Sliding angulation osteotomy is a technically simple procedure, which achieves lengthening and angulation of the ulna simultaneously in the sagittal plane and reduces the radial head.     

Stand-alone ALIF with integrated intracorporeal anchoring plates in the treatment of degenerative lumbar disc disease: a prospective study on 65 cases

Purpose

ALIF with cages is expected to restore disc height and stabilize the spine promoting fusion, while avoiding damage attributed to rod-pedicle screw fixation. However, it may be related to an increased risk of fusion failure and subsidence. A prospective study was conducted by five investigators across three centers to confirm performance of a PEEK cage for stand-alone ALIF in the treatment of lumbar degenerative disc disease (DDD).

Methods

Sixty-five patients, with back ± leg pain, requiring surgery for DDD, were included. Efficacy and safety were evaluated at 6 weeks, 3, 6, and 12 months post-operatively. Fusion and subsidence were assessed through CT-images at 12-month follow-up. Disc height was measured. Clinical outcomes included back and leg pain (VAS), disability (Oswestry Disability Index), Quality of Life (Short-Form 36), and adverse events.

Results

The fusion and the subsidence rates were 96.3 and 2.0 %, respectively. ALIF surgery restored anterior and posterior disc height compared to baseline. There were no device-related serious adverse events, and no revision surgeries. Clinical outcomes improved significantly through 12-month follow-up.

Conclusion

Safety and efficacy of this stand-alone cage with integrated intracorporeal plates was confirmed through 12 months for treatment of degenerative conditions. The design of the cage and plates may contribute to the decreased subsidence rate observed.     

Relationship between neovascularization and degenerative changes in herniated lumbar intervertebral discs

Purpose

Lumbar disc degeneration may be associated with intensity of neovascularization in disc herniations. Our study was designed to evaluate how much the severity of histodegeneration is related to the development of neovascularization and to the level of pleiotrophin in the herniated lumbar discs.

Methods

Surgically excised lumbar disc specimens were obtained from 29 patients with noncontained (i.e., extruding through the posterior longitudinal ligament) and 21 patients with contained disc herniations. The histodegeneration scores and levels of neovascularization were estimated according to semiquantitative analysis in lumbar disc and endplate samples. Immunohistochemical staining were performed to identify the newly formed blood vessels and to detect the presence of pleiotrophin in the specimens.

Results

Higher levels of disc and endplate neovascularity were registered in noncontained herniations. The level of neovascularization was significantly related to the score of histodegeneration in the herniated disc tissues but not in the endplate specimens. Both contained and noncontained herniations had the highest values of histodegeneration in conjunction with the highest level of neovascularization but the relations between neovascularity and degenerative changes remained to be significant only in the group of noncontained herniations. Registration or frequency of pleiotrophin positive cells did not correlate significantly with histodegeneration or level of neovascularization in the disc samples.

Conclusion

Severe histodegeneration of the lumbar disc herniations is associated with enhanced neovascularization and potentially also spontaneous regression of the herniated tissue.     

Prospective study on serum metal levels in patients with metal-on-metal lumbar disc arthroplasty

Purpose

Metal-on-metal total disc replacement is a recent alternative treatment for degenerative disc disease. Wear and corrosion of these implants can lead to local and systemic transport of metal debris. This prospective longitudinal study examined the serum chromium and cobalt levels in 24 patients with cobalt–chromium alloy metal-on-metal lumbar disc replacements.

Methods

Serum was assayed for chromium (Cr) and cobalt (Co) using high-resolution inductively-coupled plasma-mass spectrometry. Detection limits were 0.015 ng/mL for Cr and 0.04 ng/mL for Co.

Results

Median serum Co levels at pre-op, 3, 6, 12, 24, and 36-months post-op were 0.10, 1.03, 0.96, 0.98, 0.67, and 0.52 ng/mL, respectively. Median serum Cr levels were 0.06, 0.49, 0.65, 0.43, 0.52, and 0.50 ng/mL, respectively.

Conclusion

In general, these results indicated that serum Co and Cr levels are elevated at all postoperative time points and are of the same order of magnitude as those observed in well-functioning metal-on-metal surface replacements of the hip and in metal-on-metal total hip replacements at similar postoperative time points.     

Sagittal balance parameters correlate with spinal conformational type and MRI changes in lumbar degenerative disc disease: results of a retrospective study

Purpose

Spinopelvic parameters can be useful in identifying risk factors for lumbar degenerative disc disease, but few studies assess patients with single-level disc herniation and most do not evaluate symptoms. This comparative retrospective study was aimed to analyse spinopelvic parameters, symptoms and MRI changes in patients with single-level lumbar disc herniation undergoing conservative or surgical treatment.

Methods

Patients with clinical and radiological assessment (Japanese Orthopaedic Association Score) and an MRI evaluation of the lumbar spine were identified and divided into two groups: surgically treated (group A) and not requiring surgery (group B). Spinopelvic parameters were determined on standing profile radiographs of the lumbar spine and pelvis, and mean values were compared to those reported in the literature for normal subjects. MRI findings were graded according to the system described by Pfirrmann et al.

Results

The study included 71 patients with single-level lumbar disc herniation: 26 in group A (39.4 ± 12.1 years) and 45 in group B (51.4 ± 17.2 years). The notable differences in spinopelvic parameter means between the two groups did not reach statistical significance. A positive correlations of age with pelvic tilt and Pfirrmann changes with pelvic incidence was only found in group A, while both groups showed highly significant positive correlations of pelvic incidence with the spine’s conformational type (p = 0.001).

Conclusions

Characteristic changes in spinopelvic parameters identified in patients with lumbar degenerative disc disease were a reduction in pelvic incidence, sacral slope and lumbar lordosis, with an increased pelvic tilt. These were found to correlate with MRI changes in surgically treated patients.

     

MRI features of the psoas major muscle in patients with low back pain

Purpose

The purpose was to investigate the changes of the psoas major muscles (PM) cross-sectional area (CSA) and fat infiltration in the PM and to investigate the association between the morphology of the PM and expression of the degenerative changes of lumbar spine in patients with low back pain (LBP).

Methods

T2-weighted scans for measurements of the CSA and analysis of fat infiltration were performed on 42 patients and 49 controls using a 1.5 Tesla MR system. For a quantitative analysis of fat tissue infiltration a 4-grade visual scale was used.

Results

Patients had bigger CSA of the PM than controls at the levels of L3/L4 and L4/L5 intervertebral disc (P < 0.05). Patients with apparent degenerative changes of the lumbar spine had smaller CSA of the PM compared to the patients without apparent changes at the levels of L3/L4 and L4/L5 (P < 0.05). At the levels of L4/L5 and L5/S1 patients with present Modic changes in the lumbar vertebral bodies showed smaller CSA of the PM compared to the patients without Modic changes (P < 0.05). However, CSA of the PM in the patients with degenerative changes of lumbar spine and Modic changes was still bigger than the one of the controls. At all analyzed levels correlation between CSAs of the PM and fat infiltration of the lumbar paraspinal muscles was negative.

Conclusion

Results suggest increased activity of the PM in LBP patients but PM also remains active regardless of the presence of degenerative and Modic changes of the lumbar spine.     

Kinematic study of the relation between the instantaneous center of rotation and degenerative changes in the cervical intervertebral disc

Purpose

We located the instantaneous center of rotation (ICR) for the cervical spine at various ages and investigated age-related changes. We evaluated the impact of cervical disc degeneration on the ICR using a scoring system based on plain radiographs.

Methods

Flexion, extension, and neutral lateral radiographs were obtained from 680 asymptomatic subjects (363 men, 317 women; ages 20–79 years) divided into six 10-year-age groups. The ICRs from C3/C4 to C6/C7 were determined from the radiographs using MIMICS software. A scoring system determined from lateral radiographs quantitatively assessed degeneration of cervical intervertebral discs. ICRs were compared among groups to analyze age-related changes and the relation between degenerative changes and ICR location.

Results

In asymptomatic subjects, the ICR was located approximately at the superior half of the lower vertebral body height and the posterior half of its width. The ICR at the C5/C6 level was located more anterior and higher in patients >50 years than in younger subgroups (P < 0.05). Degenerative changes produced more anterosuperior translation of the ICR, which was significantly correlated with height loss (P < 0.05). In moderately or severely degenerated segments, the ICR location change reached statistical significance (P < 0.05).

Conclusions

Baseline data for Chinese cervical spine ICRs were established for the third through eighth decade of life, including age-related changes and the kinematic effects of degenerative change on the ICR in the functional spine unit. These findings should be considered in clinical practice and when designing disc prostheses.     

Lumbar spine MRI in upright position for diagnosing acute and chronic low back pain: statistical analysis of morphological changes

Background

Patients with low back pain frequently demonstrate recumbent magnetic resonance imaging (MRI) alterations not always related to homogeneous clinical symptoms. The purpose of this study was to evaluate and quantify the statistical significance of variations of some anatomical parameters of the lumbosacral spine and reveal occult disc pathologies from recumbent to upright position in patients with acute and chronic low back pain.

Materials and methods

Fifty-seven patients complaining of low back pain (27 women, 30 men) underwent dynamic lumbosacral MRI with a 0.25-T tilting system (G-scan Esaote). We settled five parameters for which variations have been evaluated: lumbosacral angle, lordosis angle, L3–L4 intersomatic disc height, L3–L4 interspinous processes distance, and widest anteroposterior dural sac diameter. Images were obtained in both recumbent and upright positions.

Results

Statistically significant differences [one-way analysis of variance (ANOVA), p = 0.0043] were found between each pair of values of parameters sampled in recumbent and upright positions. In 70 % of patients, on visual qualitative analysis only, an increment of disc protrusions and/or spondylolisthesis was found in the upright position; in three cases, in the upright position only, an interarticular pseudocyst was found.

Conclusions

Dynamic MRI with an open-configuration, low-field tilting MRI system is a feasible and promising tool to study degenerative pathology of the spine. Moreover, in cases of low back pain with negative MRI in the recumbent position or in patients with pain in the upright position only, tilting MRI permits visualization of occult spine and disc pathologies in patients with acute or chronic low back pain.     

Risk factors for subsidence in anterior cervical fusion with stand-alone polyetheretherketone (PEEK) cages: a review of 82 cases and 182 levels

Introduction

To determine risk factors for subsidence in patients treated with anterior cervical discectomy and fusion (ACDF) and stand-alone polyetheretherketone (PEEK) cages.

Materials and methods

Records of patients with degenerative spondylosis or traumatic disc herniation resulting in radiculopathy or myelopathy between C2 and C7 who underwent ACDF with stand-alone PEEK cages were retrospectively reviewed. Cages were filled with autogenous cancellous bone harvested from iliac crest or hydroxyapatite. Subsidence was defined as a decrease of 3 mm or more of anterior or posterior disc height from that measured on the postoperative radiograph. Eighty-two patients (32 males, 50 females; 182 treatment levels) were included in the analysis.

Results

Most patients had 1–2 treatment levels (62.2 %), and 37.8 % had 3–4 treatment levels. Treatment levels were from C2–7. Of the 82 patients, cage subsidence occurred in 31 patients, and at 39 treatment levels. Multivariable analysis showed that subsidence was more likely to occur in patients with more than two treatment levels, and more likely to occur at treatment levels C5–7 than at levels C2–5. Subsidence was not associated with postoperative alignment change but associated with more disc height change (relatively oversized cage).

Conclusion

Subsidence is associated with a greater number of treatment levels, treatment at C5–7 and relatively oversized cage use.     

Anatomical transosseous fixation of the deep and superficial fibers of the radioulnar ligaments

Introduction

The triangular fibrocartilage complex is in conjunction with the interosseous membrane the most important stabilizer of the distal radioulnar joint. Lesions of the triangular fibrocartilage complex may cause instability of the distal radioulnar joint with serious consequences. Therefore, the goal is to reconstruct and provide stability to prevent further harm.

Surgical technique

Based on the anatomical configuration of the radioulnar ligaments, we present a technique which addresses both the deep and the superficial fibers of the radioulnar ligaments. This surgical procedure can be performed either openly or arthroscopically assisted. Two osseous 2-mm tunnels starting from the ulnar neck to the foveal surface are created. A nonabsorbable suture is passed through the tunnels and the triangular fibrocartilage using a 20-gauge venipuncture needle in order to attach the deep fibers. Then a third osseous tunnel starting from the lateral base of the styloid process to the medial aspect is created. The suture is passed through this tunnel and through the triangular fibrocartilage and around the styloid process palmarily using the same needle as before in order to anchor the superficial fibers anatomically. After reducing the ulna head the sutures are tightened.

Conclusion

This technique is quite simple and addresses the anatomical configuration of the radioulnar ligaments.     

The translaminar approach for cranially extruded lumbar disc herniations

Objective

To remove extruded disc fragments impinging the exiting root. To spare the interlaminar space and the facet joint.

Indication

Cranially migrated disc herniation.

Contraindication

Severe spinal canal stenosis.

Surgical technique

Microscope from skin to skin, 25 mm skin incision about 5 mm off the midline, conventional subperiosteal route or transmuscular access by blunt splitting the multifidus muscle. A translaminar hole (diameter 10 mm) is drilled off. The epidural exploration starts along the thecal sac until the axilla of the exiting root is reached. An extruded or subligamentous disc fragment(s) is removed. If an extensive annular perforation is detected, the disc space should be cleared (20% of the cases).

Postoperative management

Same day mobilization.

Results

A total of 84 patients (46 men) underwent the translaminar approach. The mean age was 57 years (range 27–80 years). Follow-up examinations by an independent observer at 1 and 6 weeks; 3, 6 and 12 months and once yearly thereafter (mean follow-up 27 months). Extruded (61%) and subligamentous (39%) disc fragments were found. In 4 cases the translaminar hole was enlarged to a laminotomy. In 12 patients the disc space was cleared. The outcome (MacNab criteria) was excellent (67%), good (27%), fair (5%), and poor (1%). The incidence of recurrent disc herniations was 7%.