Surgical fusion in childhood spondylolisthesis

Minimally Invasive Surgery for Managing Grade IV and V Spondylolisthesis

Surgical treatment of high-grade spondylolisthesis is controversial and aims at restoring the spinopelvic sagittal balance through complete or partial reduction of the listhesis. Nerve decompression and interbody fusion are necessary for patients presenting with neurological deficit, severe pain, lower limb asymmetry, or deformities. We present the case and the results of a patient with high-grade spondylolisthesis, in whom minimally invasive management was performed. A narrative review in this topic is also provided. We performed a literature review of high-grade spondylolisthesis to compare our technique to current surgical alternatives. We included articles from PubMed, Embase, Scopus, Ovid, and Science Direct published between 1963 and 2022 that were written in English, German, and Spanish. The terms used were the following: "high grade spondylolisthesis," "spondyloptosis," "surgical management," "interbody fusion," and "arthrodesis." In all, 485 articles were displayed, from which we filtered 112 by title and abstract. At the end, 75 references were selected for the review. Different interbody fusion techniques can be used to correct the lumbosacral kyphosis and restore the spinopelvic parameters. A complete reduction of the listhesis is not always required. The surgical procedure carried out in our patient corresponds to the first known case of minimally invasive circumferential arthrodesis with iliac screws and sacral fixation in a high-grade dysplastic spondylolisthesis. This approach guarantees the correction of the lumbosacral kyphosis and a complete reduction of the listhesis. Further studies are required to determine whether the results of this case can be extrapolated to other patients with high-grade spondylolisthesis.

Preoperative and Postoperative, Three-dimensional Gait Analysis in Surgically Treated Patients With High-grade Spondylolisthesis

BACKGROUND

High-grade spondylolisthesis (HGS) (Myerding grade III-V) in adolescents can lead to a marked alteration of gait pattern and maybe the presenting symptom in these patients. This characteristic gait pattern in patients with HGS has been referred to as the "pelvic waddle." Modern 3-dimensional (3D) gait analysis serves an important tool to objectively analyze the different components of this characteristic gait preoperatively and postoperatively and is an objective measure of postoperative improvement.This study demonstrates the use of 3D gait analysis preoperatively and postoperatively in a cohort of 4 consecutive patients with HGS treated surgically at a single tertiary referral center and utilize this to objectively evaluate outcome of surgical treatment in these patients. This has not been reported previously in a cohort of patients.

METHODS

This is a prospective analysis of patients with HGS who underwent surgical intervention for spondylolisthesis at a single institution. Patient demographics, clinical, and radiologic assessment were recorded, and all patients underwent 3D gait analysis before and after surgical intervention. Kinetic, kinematic, and spatial parameters were recorded preoperatively and postoperatively for all patients. This allowed the outcome of change in gait deviation index, before and after surgical treatment, to be evaluated.

RESULTS

We were able to review complete records of 4 adolescent patients who underwent surgical treatment for HGS. Mean age at surgery was 13.5 years with a minimum follow-up of 2.5 years postoperatively (average 40 mo). Preoperative gait analysis revealed marked posterior pelvic tilt in 2 patients, reduced hip and knee extension in all 4 patients and external foot progression in 3 of the 4 patients. Along with an observed improvement in gait, there was an objective improvement in gait parameters postoperatively in all 4 patients. Gait deviation index score improved significantly from 78.9 to 101.3 (mean).

CONCLUSIONS

Preoperative gait abnormalities exist in HGS and can be objectively analyzed with gait analysis. Surgical intervention may successfully resolve these gait abnormalities and gait analysis is a useful tool to assess the outcome of surgery and quantify an otherwise intangible benefit of surgical intervention.

LEVEL OF EVIDENCE

Level IV-case series.

Current Evidence Regarding the Treatment of Pediatric Lumbar Spondylolisthesis: A Report From the Scoliosis Research Society Evidence Based Medicine Committee

STUDY DESIGN

Structured literature review.

OBJECTIVES

The Scoliosis Research Society requested an assessment of the current state of peer-reviewed evidence regarding pediatric lumbar spondylolisthesis to identify what is known and what research remains essential to further understanding.

SUMMARY OF BACKGROUND DATA

Pediatric lumbar spondylolisthesis is common, yet no formal synthesis of the published literature regarding treatment has been previously performed.

METHODS

A comprehensive literature search was performed. From 6600 initial citations with abstract, 663 articles underwent full-text review. The best available evidence regarding surgical and medical/interventional treatment was provided by 51 studies. None of the studies were graded Level I or II evidence. Eighteen of the studies were Level III, representing the current best available evidence. Thirty-three of the studies were Level IV.

RESULTS

Although studies suggest a benign course for "low grade" (<50% slip) isthmic spondylolisthesis, extensive literature suggests that a substantial number of patients present for treatment with pain and activity limitations. Pain resolution and return to activity is common with both medical/interventional and operative treatment. The role of medical/interventional bracing is not well established. Uninstrumented posterolateral fusion has been reported to produce good clinical results, but concerns regarding nonunion exist. Risk of slip progression is a specific concern in the "high grade" or dysplastic type. Although medical/interventional observation has been reported to be reasonable in a small series of asymptomatic high-grade slip patients, surgical treatment is commonly recommended to prevent progression. There is Level III evidence that instrumentation and reduction lowers the risk of nonunion, and that circumferential fusion is superior to posterior-only or anterior-only fusion. There is Level III evidence that patients with a higher slip angle are more likely to fail medical/interventional treatment of high-grade spondylolisthesis.

CONCLUSIONS

The current "best available" evidence to guide the treatment of pediatric spondylolisthesis is presented.

LEVEL OF EVIDENCE

Level III; review of Level III studies.

What is the optimum fusion technique for adult spondylolisthesis-PLIF or PLF or PLIF plus PLF? A meta-analysis from 17 comparative studies

STUDY DESIGN

A meta-analysis and systemic review.

OBJECTIVE

To pool scientific evidence for the optimum selection in the treatment of lumbar spondylolisthesis by comparing the clinical effect of posterolateral fusion (PLF), posterior lumbar interbody fusion (PLIF), and PLIF plus PLF.

SUMMARY OF BACKGROUND DATA

Clinical effect of the 3 fusion techniques has been reported in many studies. However, which is the best method is in dispute.

METHODS

A systematic search was conducted in MEDLINE, EMBASE, and the Cochrane Collaboration Library from January 1950 through May 2013. Comparative studies were performed according to eligibility criteria. Weighted mean differences and risk differences were calculated for common outcomes. The final strength of evidence was expressed as different level recommended by the Grading of Recommendations Assessment, Development, and Evaluation Working Group.

RESULTS

Four randomized controlled trials and 13 observational studies were eligible. PLIF was more effective than PLF in the improvement of clinical satisfaction (odds ratio [OR], 0.52; 95% confidence interval (CI), 0.31-0.89; P=0.02). No significant differences in the primary outcomes were seen between PLIF plus PLF and PLF (OR, 0.88; 95% CI, 0.47-1.64; P=0.69). For the complication rate, the differences were not significant between PLIF and PLF, and between PLIF plus PLF and PLF (OR, 2.27; 95% CI, 0.95-5.42; P=0.07; OR, 0.74; 95% CI, 0.22-2.44; P=0.62, respectively). In the secondary outcomes, PLIF was more effective than PLF in the improvement of fusion rate (P=0.0007) and reoperation rate (P=0.004). However, PLIF plus PLF failed to reveal more superiority than PLF (P>0.05).

CONCLUSION

PLIF plus PLF did not show more superiority than PLF alone. PLIF alone improved clinical satisfaction and decreased complication rate compared with PLF. PLIF maybe be better than the other 2 fusion methods in the treatment of lumbar spondylolisthesis. However, conclusions need to be treated with caution because of lack of high quality of evidence.

LEVEL OF EVIDENCE

1.

Management of high-grade spondylolisthesis

Management of high-grade spondylolisthesis (HGS) remains challenging and is associated with significant controversies. The best surgical procedure remains debatable. Although the need for instrumentation is generally agreed upon, significant controversies still surround the role of reduction and anterior column support in the surgical management of HGS. Complications with operative management of HGS can be significant and often dictate the selection of surgical approach. This review highlights the pathophysiology, classification, clinical presentation, and management controversies of HGS, in light of recent advances in our understanding of the importance of sagittal spinopelvic alignment and technologic advancements.

Morbidity and mortality in the surgical treatment of six hundred five pediatric patients with isthmic or dysplastic spondylolisthesis

STUDY DESIGN

Retrospective analysis of prospectively collected database.

OBJECTIVE

To analyze the rate of complications, including neurologic deficits, associated with operative treatment of pediatric isthmic and dysplastic spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Pediatric isthmic and dysplastic spondylolisthesis are relatively uncommon dis-orders. Several prior studies have suggested a high rate of complication associated with operative intervention. How-ever, most of these studies were performed with sufficiently small sample sizes such that the presence of one complication could significantly affect the overall rate. The Scoliosis Research Society (SRS) prospectively collects morbidity and mortality (M&M) data from its members. This multicentered, multisurgeon database permits analysis of the surgical treatment of this relatively rare condition on an aggregate scale and provides surgeons with useful information for preoperative counseling.

METHODS

Patients who underwent surgical treatment for isthmic or dysplastic spondylolisthesis from 2004 to 2007 were identified from the SRS M&M database. Inclusion criteria for analysis included age ≤ 21 and a primary diagnosis of isthmic or dysplastic spondylolisthesis.

RESULTS

Of 25,432 pediatric cases reported, there were a total of 605 (2.4%) cases of pediatric dysplastic (n ∇ 62, 10%) and isthmic (n ∇ 543, 90%) spondylolisthesis, with a mean age of 15 years (range, 4-21). Approximately 50% presented with neural element compression, and less than 1% of cases were revisions. Surgical procedures included fusions in 92%, osteotomies in 39%, and reductions in 38%. The overall complication rate was 10.4%. The most common complications included postoperative neurologic deficit (n ∇ 31, 5%), dural tear (n ∇ 8, 1.3%), and wound infection (n ∇ 12, 2%). Perioperative deep venous thrombosis and pulmonary embolus were reported in 2 (0.3%) and 1 (0.2%) patients, respectively. There were no deaths in this series.

CONCLUSION

Pediatric isthmic and dysplastic spondylolisthesis are relatively uncommon disorders, representing only 2.4% of pediatric spine procedures in the present study. Even among experienced spine surgeons, surgical treatment of these spinal conditions is associated with a relatively high morbidity.

Contemporary management of isthmic spondylolisthesis: pediatric and adult

BACKGROUND

Isthmic spondylolisthesis is common in pediatric and adult patients. Most cases are asymptomatic. When symptomatic, nonsurgical treatment is an appropriate first step. Surgical treatment of this condition varies depending on patient age, degree of slip, presence of neurologic findings, and degree of deformity.

PURPOSE

To review the literature on the management of isthmic spondylolisthesis in pediatric and adult patients.

STUDY DESIGN

Review article.

METHODS

Literature review.

RESULTS AND CONCLUSIONS

Achieving a solid fusion leads to improved functional outcomes and reduction in pain. A circumferential fusion is associated with a higher fusion rate and has become more common, especially with high-grade slips. The need for reduction is controversial and is mostly indicated for patients with significant lumbosacral kyphosis and sagittal imbalance.

Spondylolisthesis: intraobserver and interobserver reliability with regard to the measurement of slip percentage

BACKGROUND

Spondylolisthesis is often diagnosed and treated on the basis of measurements obtained from radiographs. Many physicians will perform surgery regardless of the patient's symptoms above a specific slip percentage. However, current methods used to assess slip percentage are vague and lack appropriate standardization, leaving physicians to devise personal evaluation techniques. This study presents a defined method to calculate slip percentage that takes advantage of modern technology, is fast and simple to perform, and shows excellent intraobserver/interobserver reliability.

METHODS

Four pediatric orthopaedic attendings each reviewed 30 radiographic cases of spondylolisthesis (grades 1 to 4) at the L5 to S1 level. The radiographs were measured twice through computer using PACS information management software with an interval of 2 days to 2 weeks between sessions. Using the PACS line tool, observers superimposed 6 lines onto each radiograph from which measurements were derived. The numerator in slip percentage (anterior displacement) was determined by 2 methods: the distance between a line outlining the posterior border of the sacrum and A: a line outlining the posterior border of L5 or B: a line parallel starting at the inferior, posterior corner of L5. The denominator in slip percent was determined by 2 methods. C: length of the inferior border L5 or D: length of the superior border of L5. This resulted in 4 different equations of slip percentage: A/C, A/D, B/C, and B/D. Analysis was performed using intraclass correlation coefficient.

RESULTS

Slip percentage=A/D resulted in the highest intraclass correlation coefficient for both intraobserver and interobserver reliability (0.87 and 0.85, respectively). Slip percentage=B/C showed the poorest intraobserver reliability (0.69). Slip percentage=B/C and B/D had equally poor interobserver reliability (0.59).

CONCLUSIONS

Defining the numerator in slip percentage as the distance between a line outlining the posterior border of the sacrum and a line outlining the posterior border of L5 (A) results in the highest intraobserver/interobserver reliability. Defining the denominator in slip percentage as the length of the superior border of L5 (D) results in the highest intra/inter observer reliability.

LEVEL OF EVIDENCE

Diagnostic level III.

Evidence-based medicine analysis of isthmic spondylolisthesis treatment including reduction versus fusion in situ for high-grade slips

STUDY DESIGN

: Literature review.

OBJECTIVES

: The purpose of this article is to review the available literature and to attempt to formulate evidence-based recommendations for the surgical treatment of high-grade spondylolisthesis in the pediatric population.

SUMMARY OF BACKGROUND DATA

: The surgical management of high-grade spondylolisthesis remains controversial due to the lack of high level evidence. Prospective randomized studies have not been completed.

METHODS

: Through an electronic database search and published literature cross-reference, appropriate studies were identified and assigned the appropriate level of evidence.

RESULTS

: There were no Level I or II evidence on this topic with our search. The best level of evidence that we have on this topic is retrospective comparative studies. We found 5 such articles which compared fusion in situ to reduction and fusion for high-grade spondylolisthesis. Pseudarthrosis rates are decreased by performing an instrumented reduction with a fusion. However, there is no significant difference in a clinical outcome of patients treated in situ versus reduction.

CONCLUSION

: Because of the paucity of high levels of evidence, we are not able to formulate clear guidelines for treatment of high-grade spondylolisthesis based on the best evidence available in the published literature.

A proposal for a surgical classification of pediatric lumbosacral spondylolisthesis based on current literature

The classification presented in this paper is the first specifically designed to guide surgical treatment of L5-S1 spondylolisthesis in children and adolescents. It also presents objective criteria to differentiate between low- and high-dysplastic spondylolisthesis and incorporates recent knowledge in the study of sagittal spinopelvic balance. The proposed classification is based on the following: (1) the degree of slip, (2) the degree of dysplasia, and (3) the sagittal spinopelvic balance. To classify a patient, the degree of slip is quantified first to determine if it is low-grade, high-grade, or a spondyloptosis. Then, the degree of dysplasia is evaluated based on seven criteria, in order to separate patients with low- and high-dysplastic spondylolisthesis. Finally, the sagittal spinopelvic balance is assessed from the measurement of the pelvic incidence (PI), sacral slope (SS), and pelvic tilt (PT). For low-grade spondylolisthesis, it is classified as low PI/low SS (nutcracker type) or high PI/high SS (shear type). For high-grade spondylolisthesis, it is classified as high SS/low PT (balanced pelvis) or low SS/high PT (retroverted pelvis). Such a comprehensive classification could allow to better evaluate and compare available surgical techniques, and to optimize the treatment of L5-S1 spondylolisthesis. Because the classification was designed so that groups are organized in an ascending order of severity, it becomes easier and more intuitive to develop an associated surgical algorithm because the complexity of the surgery should increase as the severity of the spondylolisthesis increases. A tentative treatment algorithm is proposed but it is not definitive because further studies are required to define the most appropriate treatment for each group.

High-grade isthmic dysplastic spondylolisthesis: monosegmental surgical treatment

STUDY DESIGN

A prospective single arm cohort. OBJECTIVE.: To study the results of distraction reduction of high-grade isthmic dysplastic spondylolisthesis with posterior lumbar interbody fusion and posterior compression in a consecutive, prospectively collected series of adolescent patients.

SUMMARY OF BACKGROUND DATA

High-grade isthmic dysplastic spondylolisthesis has been associated with a high complication and failure rate regardless of the method of surgical treatment, including in situ fusion, cast correction and fusion, anterior fusion, posterior instrumented fusion, and combination procedures.

METHODS

A total of 18 adolescents with the diagnosis and a minimum 50% slip underwent the procedure of Gill decompression, temporary distraction with reduction of the deformity, complete lumbosacral discectomy, posterior lumbar interbody fusion with Harm's cage and autogenous iliac graft, and posterior monosegmental compression instrumentation with pedicular fixation.

RESULTS

Follow-up ranged from 2.3 to 5 years. Slip improved from 77% to 13% and slip angle from 35 degrees to 3.8 degrees initially and 4.3 degrees at final follow-up. One patient had loss of 16 degrees of slip angle but achieved arthrodesis. Sacral inclination improved from 28 degrees to 39 degrees . There were no neurologic or infectious complications. There were no overt instrumentation failures. Arthrodesis was achieved in every instance. Two patients had structural complications, neither of which underwent reoperation.

CONCLUSIONS

The index procedure provided near-anatomic correction of high-grade spondylolisthesis, which is maintained at a minimum 2-year follow-up without significant complications. There were two structural complications. Anterior column structural support and posterior compressive instrumentation help restore the necessary biomechanics to allow clinical fusion and success. This series has led the senior author to evolve his technique too ften include caudad fixation to the pelvis and/or cephalad fixation to L4.

Anterior column support in surgery for high-grade, isthmic spondylolisthesis

The literature is confusing as to the need for anterior column fusion in the surgical treatment of patients with high-grade dysplastic spondylolisthesis. The current authors present an analysis of consecutive pediatric patients treated surgically for high-grade spondylolisthesis with and without anterior column structural support with emphasis on fusion rates, segmental kyphosis correction, and functional outcomes. Thirty-seven surgical procedures were done in 31 patients for Meyerding Grade 3 or Grade 4 isthmic dysplastic spondylolisthesis. Patients were separated into two groups based on whether they had structural anterior column support (tricortical autogenous iliac crest) in addition to posterior fusion surgery. Group 1 consisted of 18 patients treated only with posterior surgery without anterior structural support (11 patients were treated with L4-sacrum posterior in situ fusion and seven patients were treated with posterior instrumented reduction with decompression and posterior fusion), and Group 2 consisted of 19 patients who had a reduction and circumferential fusion including anterior structural support. All patients had new radiographs taken at the time of followup (average, 3.1 years, range, 2 years-10 years 1 month) and completed a functional outcome questionnaire. The incidence of pseudarthrosis was 39% (seven of 18 patients) in Group 1 and 0% (0 of 19) in Group 2. All seven patients who had pseudarthrosis achieved solid fusion with a second procedure involving circumferential fusion with anterior column structural grafting. Outcomes regarding pain after treatment, function, and satisfaction were high in those patients who achieved solid fusion regardless of surgical procedure.

Spondylolisthesis in the Young Athlete

In brief Young athletes with persistent unexplained low-back pain or tight hamstrings should be evaluated for possible spondylolisthesis. Although the physical examination is often unrevealing, hamstring tightness is a common finding in symptomatic patients. Anteroposterior, lateral, and possibly right and left oblique x-rays of the lumbosacral spine will suggest the diagnosis. The degree of vertebral slippage and the presence or absence of symptoms will determine whether conservative therapy or operative intervention is appropriate.

Spondylolysis and spondylolisthesis

Lysis is common and its causes are mainly constitutional. Most of slipping has already occurred when the patient comes for consultation. A further progress is often caused by disc pathology. Neurological deficits are rare. A high-degree olisthesis and L4 location are risk factors for future back pain. Asymptomatic lysis with or without olisthesis should not be treated. A posterolateral fusion in situ without instrumentation gives good results in adolescents and young adults, whereas old patients benefit from instrumentation. Reduction cannot be recommended as a routine method.