Isthmic spondylolisthesis treated with circumferential arthrodesis (ALIF and posterior fixation): correction, fusion and indirect decompression

There is no consensus regarding the choice of the surgical technique for isthmic spondylolisthesis treatment, although they all aim to a common goal, achieving fusion at the index level while restoring an appropriate lordosis and remove potential radicular compression. Analyze outcome of circumferential arthrodesis (CA) with ALIF (Anterior Lumbar Interbody Fusion) and pedicle screw fixation for the treatment of all-grade isthmic spondylolisthesis, with indirect neurological decompression. Retrospective study of isthmic spondylolisthesis treated with CA, with one-year follow-up. Clinical scores were collected at one year: VAS-L, VAS-R and ODI. Pelvic parameters, L4-S1 lordosis and at index and adjacent levels, and lumbo-sacral angle (LSA) were measured pre- and post-operatively and at last follow-up. Foraminal surface and diameters were measured pre- operatively and at follow-up on CT-Scan. Level of evidence: IV. 87 patients were included. Mean VAS-L was 2.3, mean VAS-R was 1, and mean ODI was 13.8%. 10% of the patients presented a high-grade spondylolisthesis and 50% a grade II. Mean lordosis at index level shifted from 6° to 18°, L4-S1 lordosis increased from 37 to 45° and LSA shifted from 116 to 125° (p<0.001). The foraminal surface increased from 50mm 2 to 70mm 2 at last follow-up mostly through the supero-inferior diameter, shifting from 7.4mm to 9.5mm (p<0.001). In LSA<90° group, mean correction was 20° at index level, 13° at L4-S1 and 21° for LSA versus 11°, 8° and 8° respectively in LSA>90° group (p<0.001). Fusion rate was estimated at 96.5%. One infection, 5 sympathetic dysfunctions, one retrograde ejaculation, one iliac vein injury, one incisional hernia, one lateral femoral cutaneous nerve injury and two adjacent syndromes have been noted. CA is an efficient technique for the treatment of isthmic spondylolisthesis of all grades, with an acceptable rate of complications. It allows a restoration of the regional lordosis as well as a foraminal widening, avoiding additional decompression.

Radiologic adjacent segment degeneration 2 years after lumbar fusion for degenerative spondylolisthesis

INTRODUCTION

Lumbar fusion is now a currently accepted treatment for degenerative lumbar spondylolisthesis (DLSP), but may induce adjacent segment degeneration (ASD). The present study hypothesis was that there are radiological parameters associated with ASD. The study objective was to determine predictive factors of ASD.

MATERIAL AND METHODS

A single-center retrospective study included patients operated on between 2006 and 2013 for DLSP. Radiological parameters were analyzed on preoperative, immediate postoperative and final follow-up lateral X-ray. ASD was defined by the following adjacent segment criteria:>3mm anteroposterior translation,>10° segmental kyphosis, or>50% loss of disc height.

RESULTS

One hundred and seven patients were included: 79% female; mean age, 67±10.2 years. Fusion involved 1 level in 67% of cases and 2 or more in 33%, with transforaminal lumbar interbody fusion (TLIF) in 27% of cases. There was overall significant gain in lumbar lordosis (mean, 3.1°; P=0.04). At a mean 27.8 months' follow-up, 29% of cases showed ASD and 10% required surgical reintervention. Preoperative anterior imbalance and long fusion (>2 levels) were significantly associated with ASD (OR=2.81, 95% CI [1.17-6.74] versus OR=2.76, 95% CI [1.15-6.63]). There were no significant differences according to postoperative radiological parameters, or to TLIF (OR=1.8, 95% CI [0.7-4.4]).

CONCLUSION

Twenty-nine percent of patients developed ASD, with a surgical revision rate of 10%. ASD risk factors comprised high number of instrumented levels and preoperative sagittal imbalance.

LEVEL OF EVIDENCE

IV, retrospective cohort.

Reduction and fusion in high-grade L5-S1 spondylolisthesis by a single posterior approach. Results in 50 patients

INTRODUCTION

Treatment strategies in high-grade L5-S1 spondylolisthesis are controversial. Reduction of slippage, correction of lumbosacral kyphosis and the necessity of a complementary anterior approach are debated in the literature. The present study reports clinical and radiological outcome for reduction and instrumented fusion on a single posterior approach.

MATERIAL AND METHOD

A retrospective study included all consecutive adolescent and young adult patients operated on by a single surgeon (D.C.) for high-grade (Meyerding 3-4-5) L5-S1 spondylolisthesis. The technique consisted in reduction of lumbosacral kyphosis and posterolateral fusion on a single posterior approach without resection of the sacral dome or complementary anterior approach. Only cases of adult ptosis required impacted tibial interbody graft. Clinical complications, radiologic lumbopelvic results and sagittal balance were analyzed at last follow-up.

RESULTS

Fifty patients, with a mean age at surgery of 21±11 years, were followed up for a mean 5.5±4.6 years. Mean lumbosacral angle was reduced by 25° (from 76° to 101°; P<0.05), and mean listhesis grade by >50% (from 75% to 23%; P<0.0001), without correction loss at last follow-up. C7 sagittal offset was corrected (from 8° to 4°; P<0.05), with harmonization of lumbar (from 57° to 64°; P<0.001) and thoracic curvature (from 37° to 44°; P=0.1). Seventeen patients (34%) showed postoperative radicular deficit, without sequelae at last follow-up. There were no cauda equina lesions. Bone fusion was achieved in 42 patients (84%), in the same surgical step. After revision by complementary interbody graft, there was no residual non-union.

CONCLUSION

Surgery on a single posterior approach gave reliable results in high-grade spondylolisthesis in adolescents and young adults. The technique is not however, free of risk (transient neurologic deficit and non-union), and patients should be forewarned. Complementary interbody graft can be reserved to adult ptosis with incomplete reduction of lumbosacral kyphosis and to revision surgery for non-union.

LEVEL OF EVIDENCE

IV, retrospective study.

Sacro-iliac joint arthroscopy for arthrodesis after traumatic dislocation. Cadaver and clinical feasibility study

BACKGROUND

Sacro-iliac arthrodesis usually requires an extended posterior approach, which is associated with a number of dreaded complications. Here, we assessed the feasibility of arthroscopic exploration of the dislocated sacro-iliac joint.

MATERIALS AND METHODS

In the first step of our study, we used ligament section to induce loss of sacro-iliac joint coaptation in a cadaver. We then studied 5 patients with Tile C pelvic ring injuries. Arthroscopy was used to clear the joint of fibrous tissue and to roughen the bone to subchondral level in order to induce sacro-iliac arthrodesis. In addition, posterior fixation was performed using a hinge system or an ilio-sacral screw.

RESULTS

The cadaver study confirmed the feasibility of sacro-iliac arthroscopy after disruption of the strong posterior inter-osseous ligament. In the clinical part of the study in 5 patients with Tile C pelvic ring injuries, arthroscopy allowed direct visualisation extending to the anterior part of the joint space. A power burr and synovial knife were introduced to remove the interposed fibrous tissue and to roughen the bone to subchondral level in order to induce joint fusion. In addition, percutaneous or open posterior fixation was performed in all 5 patients. No infectious complications were recorded.

DISCUSSION

An arthroscope cannot be introduced into the normal sacro-iliac joint. In contrast, after traumatic sacro-iliac dislocation, arthroscopy can be used to evaluate the intra-articular injuries and to roughen the bone to subchondral level.

Incidence and predictors of missed injuries in trauma patients in the initial hot report of whole-body CT scan

BACKGROUND

Whole-body CT scan is the cornerstone of trauma-related injury assessment. Several lines of evidence indicate that significant number of injuries may remain undetected after the initial hot report of CT. Missed injuries (MI) represent an important issue in trauma patients, for they may increase morbidity, mortality and costs. The aim of this study was to examine incidence and predictors of MI in trauma patients undergoing whole-body CT scan.

METHODS

177 CT scan performed upon admission of trauma patients during year 2005 were reviewed by a radiologist blinded to patient's initial data. MI was defined as injuries not written in the initial report. Patients with and without MI were compared to determine predictors of MI by multivariable analysis.

RESULTS

157 MI were diagnosed in 85 (47%) patients. MI was predominantly encoded AIS 2 (57%) or 3 (29%). Patients with MI had significantly higher SAPSII, higher ISS and were more frequently sedated. Age over 50 years (OR: 4.37, p=0.003) and ISS over 14 (OR: 4.17, p<0.0001) were independent predictors of MI. Median ISS after encoding MI was significantly higher than initial ISS (22 vs. 20 p<0.0001). After adjustment for severity, mortality and length of stay were not different between patients with or without MI.

CONCLUSION

Trauma patients, especially aged and severe, experienced a high rate of missed injuries in the initial hot report which appeared to be predominantly minor and musculoskeletal, advocating a CT scan second reading.

Infections in the operated spine: update on risk management and therapeutic strategies

Among the possible risks of spine surgery, surgical site infection (SSI) is far from negligible. Incidence is higher than in other locomotor system procedures, with more severe local and general impact. Certain broad guidelines can be formulated. The risk of SSI should be taken into account in the choice of treatment options discussed with the patient. Antibiotic prophylaxis, surgical prevention of iatrogenic infection and an SSI surveillance protocol should be implemented. SSI should be suspected in case of any abnormality in postoperative course, and biological and imaging (MRI or CT) measures should be taken. Local sampling for bacteriological identification is mandatory. Treatment strategy should ideally be discussed in a multidisciplinary coordination meeting, and adapted in the light of local bacterial ecology and resistance data. The information provided to the patient should be transparent and adapted to the patient's individual context.

LEVEL OF EVIDENCE

Level V.

Odontoid process pathologic fracture in spinal tuberculosis

Craniovertebral junction tuberculosis is a rare lesion in which treatment remains controversial. Options range from conservative treatment to surgery, independently of any associated neurological threat. We here report the first case of pathologic odontoid fracture in a context of spinal tuberculosis, complicated by unusual neurological evolution. The patient presented with non-contiguous multifocal tuberculosis, of which there have previously been only 6 reported cases.

Pelvic ring fractures internal fixation: iliosacral screws versus sacroiliac hinge fixation

INTRODUCTION

Pelvic ring fractures are severe injuries whose functional results depend on the quality of reduction. Numerous internal fixation alternatives have been described, but the biomechanical studies comparing them remain rare.

HYPOTHESIS

This study compared the biomechanical behavior of iliosacral screws (ISS) with sacroiliac hinge type fixation (SIF) following unstable pelvic ring fractures fixation.

MATERIALS AND METHODS

A lesion simulating sacroiliac disruption and pubic disruption was created on 14 cadaver pelves. After randomization, the fractures were internally fixed using an anterior plate associated with either an ISS or an SIF. The specimens were then submitted to forces applied vertically at the coxofemoral joints. Relative movements in vertical translation and in rotation between the iliac wing and the sacrum, as well as the stiffness and the forces at failure of the assemblies were measured and compared.

RESULTS

The mean age of the bodies was 66 years (+/-8). No significant difference was demonstrated between the groups in terms of residual motion and stiffness in both vertical and rotational displacement. The results showed a slight residual mobility in rotation of the hemipelvis. The SIFs presented greater, although non significant resistance to failure. No fixation, however, restituted stiffness comparable to a healthy pelvis.

DISCUSSION

The results of this study show that a Tile C.1.2-type injury to the pelvic ring can be treated as effectively with ISS or SIF when combined anterior and posterior fixations are performed. SIF therefore seems reliable and its continued use is justified. The long-term clinical outcomes should nevertheless be evaluated, notably on the younger population, more often affected by this type of injury.

[Paraplegia after interlaminar epidural steroid injection: a case report]

We report the first case of paraplegia observed after epidural steroid injection in the upper spine. The patient was a 42-year-old male who underwent surgery two years earlier for stenosis of the lumbar spine from L2 to the sacrum leading to early manifestations of an equina cauda syndrome. This first operation provided satisfactory function with complete resolution of the objective neurological symptoms. The patient later developed bilateral radiculalgia involving the L3 and L4 territories and was treated by radio-guided epidural steroid injection (125 mg hydrocortancyl) delivered in the L1-L2 interlaminar space. The injection was achieved with no technical difficulty and there was no injury to the dural sac. Immediately after the injection, the patient developed complete motor and sensorial paraplegia from T12. CT and MRI performed 30 min and 4h, respectively, after the accident revealed a medium-sized discal herniation behind the L2 body. No other lesion was observed. Emergency surgery was performed for radicular release but to no avail. The patient's neurological status remained unchanged and four days later the T2 MRI sequence revealed a high-intensity intramedullar signal in the cone. The diagnosis of ischemia of the medullary cone was retained, hypothetically by injury to the dominant radiculomedullary artery via an undetermined mechanism. This complication has been previously described after upper foraminal steroid injections but not after intralaminar epidural steroid injection.

[Influence of disc height on outcome of posterolateral fusion]

PURPOSE OF THE STUDY

Experimentally, posterolateral fusion only provides incomplete control of flexion-extension, rotation and lateral inclination forces. The stability deficit increases with increasing height of the anterior intervertebral space, which for some warrants the adjunction of an intersomatic arthrodesis in addition to the posterolateral graft. Few studies have been devoted to the impact of disc height on the outcome of posterolateral fusion. The purpose of this work was to investigate the spinal segment immobilized by the posterolateral fusion: height of the anterior intervertebral space, the clinical and radiographic impact of changes in disc height, and the short- and long-term impact of disc height measured preoperatively on clinical and radiographic outcome.

MATERIALS AND METHODS

In order to obtain a homogeneous group of patients, the series was limited to patients undergoing posterolateral arthrodesis for degenerative spondylolisthesis, in combination with radicular release. This was a retrospective analysis of a consecutive series of 66 patients with mean 52 months follow-up (range 3-63 months). A dedicated self-administered questionnaire was used to collect data on pre- and postoperative function, the SF-36 quality of life score, and patient satisfaction. Pre- and postoperative (early, one year, last follow-up) radiographic data were recorded: olisthesic level, disc height, intervertebral angle, intervertebral mobility (angular, anteroposterior), and global measures of sagittal balance (thoracic kyphosis, lumbar lordosis, T9 sagittal tilt, pelvic version, pelvic incidence, sacral slope). SpineView was used for all measures. Univariate analysis searched for correlations between variation in disc height and early postoperative function and quality of fusion at last follow-up. Multivariate analysis was applied to the following preoperative parameters: intervertebral angle, disc height, intervertebral mobility, sagittal balance parameters, use of osteosynthesis or not.

RESULTS

At the olisthesic level, there was a 30% mean decrease in disc height and intervertebral angle. These variations were not correlated with functional outcome or quality of fusion observed at last follow-up. Disc height preoperatively did not affect these variations. The only factor correlated with decreased disc height was T9 sagittal tilt: disc height decreased more when T9 sagittal tilt approached 0 degrees .

DISCUSSION

In this very restricted context (retrospective study, short arthrodesis for degenerative spondylolisthesis), we were unable to find any evidence supporting the notion that high disc height is an argument which should favor complementary intersomatic arthrodesis in combination with posterolateral fusion. Analysis of the spinal balance in the sagittal plane would probably allow a more pertinent assessment of the specific needs of individual patients.

[Superior mesenteric artery syndrome following correction of spinal deformity: case report and review of the literature]

Superior mesenteric artery syndrome is a rare complication which can develop after surgical correction of a spinal deformity. The syndrome is caused by an extrinsic compression on the third portion of the duodenum by the aorta posteriorly and the mesenteric artery anteriorly. We report here a case of aortomesenteric compression of the duodenum secondary to surgical correction of lower thoracic scoliosis in a 19-year-old female. The patient presented vomiting and intestinal obstruction ten days after spinal surgery. Treatment consisted in exclusive parenteral nutrition followed by careful surveillance and progressive reintroduction of oral food intake to avoid unnecessary surgery. Young thin subjects are predominantly exposed to this type of complication. The body mass index is a good indication to identify subjects at risk. Symptoms of upper gastrointestinal obstruction develop seven to ten days after surgery. Diagnosis is based on transit studies using a hydroluble contrast agent which reveals major gastric dilation and a clear interruption of the transit at the level of the third duodenum as well as retrograde peristaltism. Medical treatment should be undertaken first and is effective in the large majority of cases. Surgery may be proposed only in the event of failure. Recurrence is exceptional. Early diagnosis, delivery of clear information for the patient and family and multidisciplinary management are important points to consider for proper care for this complication which if neglected can become life-threatening.

[Sagittal balance of the spine and degenerative spondylolisthesis]

PURPOSE OF THE STUDY

Several reports have examined the pathophysiology of degenerative spondylolisthesis. Very little work has however been devoted to the influence of spinal balance in the sagittal plane in its pathogenesis. The purpose of this work was to present a descriptive analysis of pelvic and spinal sagittal balance in a cohort of seventy patients treated for degenerative spondylolisthesis and to compare findings with those established in a population of 250 volunteers. The goal was to deduct pathophysiological hypotheses and identify therapeutic implications.

MATERIAL AND METHODS

Seventy patients were included in this study. The following variables were noted: pelvic incidence and version, sacral slope, lumbar lordosis, thoracic kyphosis, T9 sagittal tilt and S1-S2 angle. These variables were measured on digitalized lateral views of the spine using a dedicated software (SpineView). Univariate analysis of the values obtained was performed to identify the variable distributions. Multivariate analysis was applied to study the relationships between these variables and to better define perturbations of spinal balance in the anteroposterior plane. The findings were compared with those obtained in a control population.

RESULTS

One of the essential characteristics of the cohort of patients with degenerative spondylolisthesis was the presence of an exaggerated pelvic incidence (62.6 degrees versus 54.7 degrees in the control population). The most significant determinants of T9 sagittal tilt (which reflects sagittal balance) were: pelvic version, pelvic incidence, lumbar lordosis, and L4-S1 local lordosis. One-third of our patients presented posterior tilt due to exaggerated thoracic kyphosis. The high pelvic incidence, via hyperlordosis and increased pelvic version, could be one of the factors favoring degenerative disease of the spinal unit.

CONCLUSIONS

This work enabled us to better describe sagittal balance in patients with degenerative spondylolisthesis and to propose hypotheses concerning the underlying mechanism of progressive degeneration. We emphasize the diversity of spinal balance in these patients and the different therapeutic implications.

Tardy occurrence of adipocyte hyperplasia in cafeteria-fed rat

White adipose tissue cellularity was studied in rats during a diet characterized by a free choice of highly palatable items. At the 8th wk the increase in adipose stores is due to hypertrophy. Between the 8th and 20th wk hypertrophy persists, but hyperplasia appears both in retroperitoneal and epididymal sites. The probable role of carbohydrate intake in the onset of hyperplasia is discussed.