Revision open anterior approaches for spine procedures

State of the art advances in minimally invasive surgery for adult spinal deformity

Adult spinal deformity (ASD) can be associated with substantial suffering due to pain and disability. Surgical intervention for achieving neural decompression and restoring physiological spinal alignment has shown to result in significant improvement in pain and disability through patient-reported outcomes. Traditional open approaches involving posterior osteotomy techniques and instrumentation are effective based on clinical outcomes but associated with high complication rates, even in the hands of the most experienced surgeons. Minimally invasive techniques may offer benefit while decreasing associated morbidity. Minimally invasive surgery (MIS) for ASD has evolved over the past 20 years, driven by improved understanding of open procedures along with novel technique development and technologic advancements. Early efforts were hindered due to suboptimal outcomes resulting from high pseudarthrosis, inadequate correction, and fixation failure rates. To address this, multi-center collaborative groups have been established to study large numbers of ASD patients which have been vital to understanding optimal patient selection and individualized management strategies. Different MIS decision-making algorithms have been described to better define appropriate candidates and interbody selection approaches in ASD. The purpose of this state of the review is to describe the evolution of MIS surgery for adult deformity with emphasis on landmark papers, and to discuss specific MIS technology for ASD, including percutaneous pedicle screw instrumentation, hyperlordotic grafts, three-dimensional navigation, and robotics.

Comparative Effectiveness Between Primary and Revision Foraminotomy for the Treatment of Lumbar Foraminal Stenosis

BACKGROUND

Foraminotomy has demonstrated clinical benefit in patients with lumbar foraminal stenosis (LFS), as evidenced by several small retrospective investigations. However, there is a subset of patients who have recurrent symptoms following the operation and therefore require revision surgery. Yet, despite this phenomenon, the relative efficacy of revision foraminotomy (RF) is not well elucidated due to limited literature on the quality of life (QOL) outcomes and cost associated with primary foraminotomy (PF) and RF.

PURPOSE

To compare the effectiveness of PF and RF in terms of QOL outcomes and relative costs.

STUDY DESIGN/SETTING

This is a retrospective cohort study conducted at a single tertiary-care institution. The patient sample consisted of patients undergoing foraminotomy for the treatment of LFS between 2008 and 2016. The primary outcome measure was improvement in postoperative QOL, as measured by EuroQol 5-Dimensions (EQ-5D), and secondary outcome measures included Pain Disability Questionnaire (PDQ) and Patient Health Questionnaire-9 (PHQ-9) perioperative cost as well as minimum clinically important difference (MCID).

METHODS

A retrospective chart review was conducted to identify individuals who underwent PF or RF for LFS and to collect clinical, operative, and demographic data. QOL scores (EQ-5D, PDQ, and PHQ-9) were collected between 2008 and 2016, and perioperative financial data were extracted via the institution's cost utilization engine. Paired t tests were used to assess changes within treatment groups, and Fisher exact tests were used for intercohort comparisons.

RESULTS

Five hundred seventy-nine procedures were eligible: 476 (82%) PF and 103 (18%) RF. A significantly higher proportion of males underwent RF than PF (71% versus 59%, P = .03), and PF was done on a significantly higher number of vertebral levels (2.2 versus 2.0, P = .04). There were no other significant differences in demographics. Preoperatively, mean PDQ-Functional scores (50 versus 54, P = .04) demonstrated significantly poorer QOL in the RF cohort. Postoperatively, EQ-5D index showed significant improvement in both the PF (0.547→0.648, P < .0001) and the RF (0.507→0.648, P < .0001) cohorts. Similarly, total PHQ-9 improved significantly in the PF cohort (7.84→5.91, P < .001) and in the RF cohort (8.55→5.53, P = .02), as did total PDQ (PF: 77→63, P < .0001; RF: 85→70, P = .04). QOL scores were also compared between groups preoperatively and postoperatively, and the only significant difference between PF and RF was observed in the preoperative PDQ-Functional score (49.7 versus 54.3, P = .04). The proportion of patients achieving MCID was not significantly associated with cohort. Finally, perioperative cost did not differ significantly between cohorts (PF: $13,383 versus RF: $13,595, P = .82).

CONCLUSIONS

Both PF and RF produced significant improvement in nearly all measures in patients with LFS. There was no significant difference in cost between PF and RF, but both PF and RF showed postoperative QOL improvements as compared with preoperative scores, indicating that RF remains a reasonable treatment option for patients with recurrent symptoms of LFS.

Sexual activity after spine surgery: a systematic review

INTRODUCTION

Sexual function is an important determinant of quality of life, and factors such as surgical approach, performance of fusion, neurological function and residual pain can affect it after spine surgery. Our aim was to perform a systematic review to collate evidence regarding the impact of spine surgery on sexual function.

METHODS

A systematic review of studies reporting measures of sexual function, and incidence of adverse sexual outcomes (retrograde ejaculation) after major spine surgery was done, regardless of spinal location. Pubmed (MEDLINE) and Google Scholar databases were queried using the following search words "Sex", "Sex life", "Sexual function", "Sexual activity", "retrograde ejaculation", "Spine", "Spine surgery", "Lumbar surgery", "Lumbar fusion", "cervical spine", "cervical fusion", "Spinal deformity", "scoliosis" and "Decompression". All articles published between 1997 and 2017 were retrieved from the database. A total of 81 studies were included in the final review.

RESULTS

Majority of the studies were retrospective case series and were low quality (Level IV) in evidence. Anterior lumbar approaches were associated with a higher incidence of retrograde ejaculation, especially with the utilization of transperitoneal laparoscopic approach. There is inconclusive evidence on the preferred sexual position following fusion, and also on the impact of BMP-2 usage on retrograde ejaculation/sexual dysfunction.

CONCLUSION

Despite limited evidence from high-quality articles, there is a general trend towards improvement of sexual activity and function after spine surgery. Future studies incorporating specific assessments of sexual activity will be required to address this important determinant of quality of life so that appropriate pre-operative counselling can be done by providers. These slides can be retrieved under Electronic Supplementary Material.

Risk factors for medical complications after long-level internal fixation in the treatment of adult degenerative scoliosis

PURPOSE

This study evaluates baseline patient characteristics and surgical parameters for risk factors of medical complications in ASD patients received posterior long level internal fixation.

METHODS

Analysis of consecutive patients who underwent posterior long-level instruction fixation for adult degenerative scoliosis (ADS) with a minimum of two year follow-up was performed. Pre-operative risk factors, intraoperative variables, peri-operative radiographic parameters, and surgical-related risk factors were collected to analyze the effect of risk factors on medical complications. Patients were separated into groups with and without medical complication. Then, complication group was further classified as major or minor medical complications. Potential risk factors were identified by univariate testing. Multivariate logistic regression was used to evaluate independent predictors of medical complications.

RESULTS

One hundred and thirty-one ADS patients who underwent posterior long segment pedicle screws fixation were included. Total medical complication incidence was 25.2%, which included infection (12.2%), neurological (11.5%), cardiopulmonary (7.6%), gastrointestinal (6.1%), and renal (1.5%) complications. Overall, 7.6% of patients developed major medical complications, and 17.6% of patients developed minor medical complications. The radiographic parameters of pre-operative and last follow-up had no significant difference between the groups of medical complications and the major or minor medical complications subgroups. However, the incidence of cerebrospinal fluid leak (CFL) in patients who without medical complications was much lower than that with medical complications (18.4 vs. 42.4%, P = 0.005). Independent risk factors for development of medical complications included smoking (OR = 6.45, P = 0.012), heart disease (OR = 10.07, P = 0.012), fusion level (OR = 2.12, P = 0.001), and length of hospital stay (LOS) (OR = 2.11, P = 0.000). Independent risk factors for development of major medical complications were diabetes (OR 6.81, P = 0.047) and heart disease (OR = 5.99, P = 0.049). Except for the last follow-up, Oswestry Disability Index and visual analog scale of the patient experienced medical complications trend higher score; the clinical outcomes have no significant difference between the medical and major complications groups.

CONCLUSION

Heart disease comorbidity is an independent risk factor for both medical and major medical complications. Smoking, fusion level, and LOS are independent risk factors for medical complication. Diabetes is the independent risk factors for major medical complications.

Mini-open Anterior Lumbar Interbody Fusion for Recurrent Lumbar Disc Herniation Following Posterior Instrumentation

STUDY DESIGN

A retrospective study.

OBJECTIVE

The aim of this study is to evaluate, clinically and radiographically, the efficacy of mini-open retroperitoneal anterior lumbar discectomy followed by anterior lumbar interbody fusion (ALIF) for recurrent lumbar disc herniation following primary posterior instrumentation.

SUMMARY OF BACKGROUND DATA

Recurrent disc herniation following previous disc surgery occurs in 5 to 15% of cases. This is often treated by further surgical intervention where posterior approach is generally preferred. However, posterior surgery may be problematic if the initial surgery involved posterior instrumentation. An anterior approach may be indicated in these patients, and recent findings suggest that a "mini-open" procedure may have some benefits when compared with traditional open techniques and their associated morbidities.

METHODS

A total of 35 recurrent lumbar disc herniation patients (10 male, 25 female) following primary posterior instrumentation with an average age of 52.8 years (range: 34-70 yrs) who underwent the mini-open ALIF procedures between August 2001 and February 2012 were evaluated retrospectively. The ALIF was performed at the levels L4-L5 (n = 14), L5-S1 (n = 15), or both L4-L5 and L5-S1 (n = 6). Visual Analog pain Scale (VAS) and Oswestry Disability Index (ODI) together with radiological results were assessed.

RESULTS

The mean operating time, intraoperative estimated blood loss, and hospital stay were 115 minutes, 70 mL, and 6 days, respectively. No blood transfusion was needed. Transient complication was recorded in two patients. Postoperative follow-up was a minimum 24.3 months. VAS score and ODI percentage decreased significantly from 7.9 ± 0.8 and 78.8% ± 12.4% pre-operatively to 1.4 ± 0.6 and 21.7 ± 4.2% at final follow-up, respectively. There was no neurological worsening and radicular pain improved significantly compared with pre-operation in all the patients. Computed tomographic reconstruction 12 and 24 months after surgery showed bony fusion, normal position, and morphology of the fusion cage in all patients.

CONCLUSION

Mini-open retroperitoneal ALIF is an effective treatment for patients with recurrent lumbar disc herniation following primary posterior instrumentation.

LEVEL OF EVIDENCE

4.

Evaluation of Anterior Vertebral Interbody Fusion Using Osteogenic Mesenchymal Stem Cells Transplanted in Collagen Sponge

STUDY DESIGN

The study used a rabbit model to achieve anterior vertebral interbody fusion using osteogenic mesenchymal stem cells (OMSCs) transplanted in collagen sponge.

OBJECTIVE

We investigated the effectiveness of graft material for anterior vertebral interbody fusion using a rabbit model by examining the OMSCs transplanted in collagen sponge.

SUMMARY OF BACKGROUND DATA

Anterior vertebral interbody fusion is commonly performed. Although autogenous bone graft remains the gold-standard fusion material, it requires a separate surgical procedure and is associated with significant short-term and long-term morbidity. Recently, mesenchymal stem cells from bone marrow have been studied in various fields, including posterolateral spinal fusion. Thus, we hypothesized that cultured OMSCs transplanted in porous collagen sponge could be used successfully even in anterior vertebral interbody fusion.

METHODS

Forty mature male White Zealand rabbits (weight, 3.5-4.5 kg) were randomly allocated to receive one of the following graft materials: porous collagen sponge plus cultured OMSCs (group I); porous collagen sponge alone (group II); autogenous bone graft (group III); and nothing (group IV). All animals underwent anterior vertebral interbody fusion at the L4/L5 level. The lumbar spine was harvested en bloc, and the new bone formation and spinal fusion was evaluated using radiographic analysis, microcomputed tomography, manual palpation test, and histologic examination at 8 and 12 weeks after surgery.

RESULTS

New bone formation and bony fusion was evident as early as 8 weeks in groups I and III. And there was no statistically significant difference between 8 and 12 weeks. At both time points, by microcomputed tomography and histologic analysis, new bone formation was observed in both groups I and III, fibrous tissue was observed and there was no new bone in both groups II and IV; by manual palpation test, bony fusion was observed in 40% (4/10) of rabbits in group I, 70% (7/10) of rabbits in group III, and 0% (0/10) of rabbits in both groups II and IV.

CONCLUSIONS

These findings suggest that mesenchymal stem cells that have been cultured with osteogenic differentiation medium and loaded with collagen sponge could induce bone formation and anterior vertebral interbody fusion. And the rabbit model we developed will be useful in evaluating the effects of graft materials for anterior vertebral interbody fusion. Further study is needed to determine the most appropriate carrier for OMSCs and the feasibility in the clinical setting.

Successful salvage surgery for failed transforaminal lumbosacral interbody fusion using the anterior transperitoneal approach

Transforaminal lumbar interbody fusion (TLIF) is a popular posterior spinal fusion technique, but sometimes require salvage surgery when implant failure occurs, which involves possible neural damage due to postoperative adhesion. The current report deals with successful anterior transperitoneal salvage surgery for failed L5‐S TLIF with less neural invasiveness.

Direct lateral retroperitoneal approach for the surgical treatment of lumbar discitis and osteomyelitis

OBJECT

The medical management of discitis and osteomyelitis with long-term antibiotic therapy and bracing usually results in eradicated infection. Surgical management is appropriate when medical management fails and in some cases with pyogenic deformity or neurological deficit. The success of surgery depends on adequate debridement of the necrotic infected disc and vertebral body, along with anterior column reconstruction and vertebral stabilization. Debridement is typically performed via an anterior retroperitoneal approach, which can necessitate mobilization of the great vessels for proper exposure. Mobilization can be technically difficult and lead to vascular injury. The purpose of this study was to evaluate an alternative technique for the surgical treatment of lumbar discitis and osteomyelitis using a direct lateral retroperitoneal approach, which allows for thorough debridement and anterior column reconstruction while avoiding the need to mobilize the great vessels.

METHODS

A retrospective chart analysis was performed for all patients who had presented with lumbar discitis and osteomyelitis and had undergone surgical management via the direct lateral retroperitoneal approach in the period from 2006 to 2013. Collected data included surgical blood loss, perioperative complications (wound infection, vascular injury, approach-related complications, and neurological injury), need for secondary procedures, microbiological and laboratory results, and efficacy of infection eradication. Imaging studies were reviewed as well.

RESULTS

Ten patients, 7 male and 3 female, underwent this procedure at the authors' institution in the defined period. Average blood loss was 272 ml (range 150-800 ml, with 800 ml in the only 2-level case). There were no vascular injuries. Average follow-up was 680 days, although 4 patients did not complete the follow-up beyond 6 months. Eight patients underwent immediate posterior pedicle screw instrumentation. Two patients did not undergo posterior instrumentation, and one of these developed a kyphotic deformity that required a secondary posterior procedure. Infection was eradicated in all patients according to a history, physical examination, imaging studies, and laboratory parameters (complete blood count, erythrocyte sedimentation rate, and C-reactive protein). One patient developed a painful neuroma at the iliac crest harvest site, and one patient had a retroperitoneal hematoma. Otherwise, there were no approach-related neurological injuries or complications. Neither was there any postoperative surgical site infection.

CONCLUSIONS

The direct lateral approach for the surgical treatment of lumbar discitis and osteomyelitis allows for thorough debridement and spinal reconstruction without the need to mobilize the great vessels. This technique effectively eradicated infection in all cases, with reasonable blood loss and no vascular injuries. This approach should be considered as an alternative to the open anterior approach. The authors recommend posterior instrumentation to prevent the development of kyphosis.

Multivariate analysis on risk factors for postoperative ileus after lateral lumbar interbody fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To assess for independent risk factors of postoperative ileus (POI) after lateral lumbar interbody fusion (LLIF).

SUMMARY OF BACKGROUND DATA

POI is frequently observed in anterior lumbar interbody fusion due to significant bowel manipulation during the approach. LLIF is a minimally invasive approach to the anterior column with reduced bowel manipulation and surgical time. However, there is a paucity of literature on POI after LLIF.

METHODS

A retrospective review was performed of records of patients who underwent LLIF from January 2006 to December 2011 at a single institution. Patients with prolonged and recurrent POI were identified by review of hospital stay documentation by a fellowship-trained spine surgeon and a research fellow. POI patients were matched 1:1 to a control cohort without POI. Uni- and multivariate analyses were performed on demographic, comorbidity, surgical indication, medication, and perioperative details to identify independent risk factors for POI.

RESULTS

Incidence of prolonged or recurrent POI after LLIF was 7.0% (42/596). Postoperative length of stay was significantly higher for patients with POI (9.9 ± 4.3 d) than control patients (5.6 ± 4.1 d) (P < 0.001). The incidence of ileus in the first 100 LLIF cases (11%) was not significantly higher than in the last 100 LLIF cases (6%) (P = 0.21). Independent risk factors were history of gastroesophageal reflux disease (P < 0.01, adjusted odds ratio [aOR]: 24.31), posterior instrumentation (P = 0.002, aOR: 19.48), and LLIF at L1-L2 (P = 0.04, aOR: 7.82). A history of prior abdominal surgery approached significance as an independent protective factor (P = 0.07, aOR: 0.29).

CONCLUSION

There was a relatively high incidence of POI after LLIF. Independent risk factors for POI were a history of gastroesophageal reflux disease, posterior instrumentation, and LLIF at L1-L2. A history of prior abdominal surgery approached significance as an independent protective factor.

LEVEL OF EVIDENCE

3.

Indications for anterior lumbar interbody fusion

Anterior lumbar interbody fusion (ALIF) has become a widely recognized surgical technique for degenerative pathology of the lumbar spine. Spinal fusion has evolved dramatically ever since the first successful internal fixation by Hadra in 1891 who used a posterior approach to wire adjacent cervical vertebrae in the treatment of fracture-dislocation. Advancements were made to reduce morbidity including bone grafting substitutes, metallic hardware instrumentation and improved surgical technique. The controversy regarding which surgical approach is best for treating various pathologies of the lumbar spine still exists. Despite being an established treatment modality, current indications of ALIF are yet to be clearly defined in the literature. This article discusses the current literature on indications on ALIF surgery.

Analysis of intraoperative difficulties and management of operative complications in revision anterior exposure of the lumbar spine: a report of 25 consecutive cases

PURPOSE

After a first anterior approach to the lumbar spine, formation of adhesions of soft tissues to the spine increases the surgical difficulties and potential for iatrogenic injury during the revision exposure. The objective of this study was to identify the intraoperative difficulties and postoperative complications associated with revision anterior lumbar spine procedures in a single institution.

METHODS

This is a retrospective review of 25 consecutive anterior revision lumbar surgeries in 22 patients (7 men and 15 women) operated on between 1998 and 2011. Patients with trauma or malignancies were excluded. The mean age of the patients at the time of revision surgery was 56 years (range 20-80 years). The complications were analyzed depending on the operative level and the time between the index surgery and the revision.

RESULTS

Six major complications (five intraoperatively and one postoperatively) occurred in five patients (20 %): three vein lacerations (12 %) and two ureteral injuries (8 %), despite the presence of a double-J ureteral stent. The three vein damages were repaired or ligated by a vascular surgeon. One of the two ureteral injuries led to a secondary nephrectomy after end-to-end anastomosis failure; the other necessitated secondary laparotomy for small bowel obstruction.

CONCLUSIONS

Anterior revision of the lumbar spine is technically challenging and is associated with a high rate of vascular or urologic complications. Therefore, the potential complications of the procedure must be weighted against its benefits. When iterative anterior lumbar approach is mandatory, exposure should be performed by an access surgeon in specialized centers that have ready access to vascular and urologic surgeons.

Minimally invasive presacral retrieval of a failed AxiaLIF rod implant: technical note and illustrative cases

BACKGROUND CONTEXT

There are few reported cases of failed axial lumbar interbody fusion (AxiaLIF) in the existing neurosurgical literature, and an anecdotal case of open paramedian retroperitoneal approach to L5-S1 level for retrieval of AxiaLIF rod has been published.

PURPOSE

The object of this study is to illustrate a minimally invasive presacral rod retrieval technique in cases with failed AxiaLIF causing lumbosacral instability.

STUDY DESIGN/SETTING

Retrospective case series.

METHODS

A retrospective analysis of the initial 26 cases of AxiaLIF done at our institution was performed; two cases of failed AxiaLIF that required rod removal were identified for detailed study. Available literature on the minimally invasive presacral techniques for rod retrieval was researched, and the use of a novel rod retrieval device with an expanding hex tip is discussed.

RESULTS

Using a minimally invasive presacral approach through the previous surgical corridor, the authors were able to retrieve the AxiaLIF rod implant and then proceed with an alternative fusion technique. Both patients improved clinically and radiographically after revision. Removal of the presacral rod was not associated with vascular or bowel complications and required minimal operating room time with minimal blood loss.

CONCLUSIONS

To the authors' knowledge, this is the first report demonstrating the safety and efficacy of minimally invasive presacral approach for removal of AxiaLIF rods in patients with failed AxiaLIF. As the AxiaLIF procedure is rapidly gaining acceptance among spine surgeons, we can expect to see increasing numbers of failed procedures as well. Understanding options for revision strategies is important for surgeons considering the use of this technique.

Perioperative risk factors related to lumbar spine fusion surgery in korean geriatric patients

Objective

Life expectancy for humans has increased dramatically and with this there has been a considerable increase in the number of patients suffering from lumbar spine disease. Symptomatic lumbar spinal disease should be treated, even in the elderly, and surgical procedures such as fusion surgery are needed for moderate to severe lumbar spinal disease. However, various perioperative complications are associated with fusion surgery. The aim of this study was to examine perioperative complications and assess risk factors associated with lumbar spinal fusion, focusing on geriatric patients at least 70 years of age in the Republic of Korea.

Methods

We retrospectively investigated 489 patients with various lumbar spinal diseases who underwent lumbar spinal fusion surgery between 2003 and 2007 at our institution. Three fusion procedures and the number of fused segments were analyzed in this study. Chronic diseases were also evaluated. Risk factors for complications and their association with age were analyzed.

Results

In this study, 74 patients experienced complications (15%). The rate of perioperative complications was significantly higher in patients 70 years of age or older than in other age groups (univariate analysis, p=0.001; multivariate analysis, p=0.004). However, perioperative complications were not significantly associated with the other factors tested (sex, comorbidities, operation procedures, fusion segments involved).

Conclusion

Increasing age was an important risk factor for perioperative complications in patients undergoing lumbar spinal fusion surgery whereas other factors were not significant. We recommend good clinical judgment and careful selection of geriatric patients undergoing lumbar spinal fusion surgery.

Revision strategies for AxiaLIF

Object

Paracoccygeal transsacral fixation is a novel percutaneous technique for arthrodesis of L5–S1 and L4–5 (Axial Lumbar Interbody Fusion [AxiaLIF]). There are no reports on feasible revision strategies. The goal of this paper is to analyze the surgical details of failed AxiaLIF constructs and to describe revision strategies.

Methods

The medical charts, operative records, and imaging studies of 5 patients with failed multisegment instrumentation using the AxiaLIF device were reviewed.

Results

AxiaLIF constructs were revised in 5 patients with a mean age of 58.4 years. All AxiaLIF devices were part of multisegment fusion constructs for revision surgery and were revised an average of 15 months after implantation. Two AxiaLIF devices were percutaneously retrieved; one because of excessive bone resorption around the AxiaLIF screw, and the other because of chronic hardware infection. In these 2 patients, the anterior column was subsequently stabilized via anterior lumbar interbody fusion. In the other 3 patients, the AxiaLIF device was left in situ. In 2 of these patients the anterior column was stabilized with bilateral L5–S1 posterior lumbar interbody fusion, and in the remaining patient with L4–5 instability the posterior instrumentation only was revised. Revision surgeries were well tolerated. One patient suffered from a wound dehiscence of the back wound.

Conclusions

AxiaLIF devices are safely retrieved using percutaneous technique. Both anterior and posterior revision strategies may be used to achieve anterior column fixation.

Complications of anterior lumbar surgery

The incidence of anterior lumbar surgery is increasing. Although adverse events are uncommon, several have been described. Complications can be categorized based on the time of occurrence (ie, intraoperative, postoperative), patient positioning, surgical exposure, and spinal procedure. Notable approach-related complications involve vascular, visceral, and neural structures. Abdominal complications have been reported. Clinically significant complications related to spinal decompression and reconstruction consist primarily of neurologic injuries and graft- and device-related problems. The rate of complications is higher in the setting of revision anterior surgery than with initial anterior lumbar surgery. A thorough understanding of the complications associated with anterior lumbar surgery will aid in prevention, recognition, and management of these rare problems. The assistance of a vascular, neurologic, or general surgeon may be helpful in avoiding or effectively managing complications.

Comparison of ICD-9–based, retrospective, and prospective assessments of perioperative complications: assessment of accuracy in reporting

Object

Large studies of ICD-9–based complication and hospital-acquired condition (HAC) chart reviews have not been validated through a comparison with prospective assessments of perioperative adverse event occurrence. Retrospective chart review, while generally assumed to underreport complication occurrence, has not been subjected to prospective study. It is unclear whether ICD-9–based population studies are more accurate than retrospective reviews or are perhaps equally susceptible to bias. To determine the validity of an ICD-9–based assessment of perioperative complications, the authors compared a prospective independent evaluation of such complications with ICD-9–based HAC data in a cohort of patients who underwent spine surgery. For further comparison, a separate retrospective review of the same cohort of patients was completed as well.

Methods

A prospective assessment of complications in spine surgery over a 6-month period (May to December 2008) was completed using an independent auditor and a validated definition of perioperative complications. The auditor maintained a prospective database, which included complications occurring in the initial 30 days after surgery. All medical adverse events were included in the assessment. All patients undergoing spine surgery during the study period were eligible for inclusion; the only exclusionary criterion used was the availability of the auditor for patient assessment. From the overall patient database, 100 patients were randomly extracted for further review; in these patients ICD-9–based HAC data were obtained from coder data. Separately, a retrospective assessment of complication incidence was completed using chart and electronic medical record review. The same definition of perioperative adverse events and the inclusion of medical adverse events were applied in the prospective, ICD-9–based, and retrospective assessments.

Results

Ninety-two patients had adequate records for the ICD-9 assessment, whereas 98 patients had adequate chart information for retrospective review. The overall complication incidence among the groups was similar (major complications: ICD-9 17.4%, retrospective 19.4%, and prospective 22.4%; minor complications: ICD-9 43.8%, retrospective 31.6%, and prospective 42.9%). However, the ICD-9–based assessment included many minor medical events not deemed complications by the auditor. Rates of specific complications were consistently underreported in both the ICD-9 and the retrospective assessments. The ICD-9 assessment underreported infection, the need for reoperation, deep wound infection, deep venous thrombosis, and new neurological deficits (p = 0.003, p < 0.0001, p < 0.0001, p = 0.0025, and p = 0.04, respectively). The retrospective review underestimated incidences of infection, the need for revision, and deep wound infection (p < 0.0001 for each). Only in the capture of new cardiac events was ICD-9–based reporting more accurate than prospective data accrual (p = 0.04). The most sensitive measure for the appreciation of complication occurrence was the prospective review, followed by the ICD-9–based assessment (p = 0.05).

Conclusions

An ICD-9–based coding of perioperative adverse events and major complications in a cohort of spine surgery patients revealed an overall complication incidence similar to that in a prospectively executed measure. In contrast, a retrospective review underestimated complication incidence. The ICD-9–based review captured many medical events of limited clinical import, inflating the overall incidence of adverse events demonstrated by this approach. In multiple categories of major, clinically significant perioperative complications, ICD-9–based and retrospective assessments significantly underestimated complication incidence. These findings illustrate a significant potential weakness and source of inaccuracy in the use of population-based ICD-9 and retrospective complication recording.

Early complications in spine surgery and relation to preoperative diagnosis: a single-center prospective study

OBJECT

The reported incidence of complications in spine surgery varies widely. Variable study methodologies may open differing avenues for potential bias, and unclear definitions of perioperative complication make analysis of the literature challenging. Although numerous studies have examined the morbidity associated with specific procedures or diagnoses, no prospective analysis has evaluated the impact of preoperative diagnosis on overall early morbidity in spine surgery. To accurately assess perioperative morbidity in patients undergoing spine surgery, a prospective analysis of all patients who underwent spine surgery by the neurosurgical service at a large tertiary care center over a 6-month period was conducted. The correlation between preoperative diagnosis and the incidence of postoperative complications was assessed.

METHODS

Data were prospectively collected on 248 consecutive patients undergoing spine surgery performed by the neurosurgical service at the Thomas Jefferson University Hospital from May to December 2008. A standardized definition of minor and major complications was applied to all adverse events occurring within 30 days of surgery. Data on diagnosis, complications, and length of stay were retrospectively assessed using stepwise multivariate analysis. Patients were analyzed by preoperative diagnosis (neoplasm, infection, degenerative disease, trauma) and level of surgery (cervical or thoracolumbar).

RESULTS

Total early complication incidence was 53.2%, with a minor complication incidence of 46.4% and a major complication incidence of 21.3%. Preoperative diagnosis correlated only with the occurrence of minor complications in the overall cohort (p = 0.02). In patients undergoing surgery of the thoracolumbar spine, preoperative diagnosis correlated with presence of a complication and the number of complications (p = 0.003). Within this group, patients with preoperative diagnoses of infection and neoplasm were more often affected by isolated and multiple complications (p = 0.05 and p = 0.02, respectively). Surgeries across the cervicothoracic and thoracolumbar junctions were associated with higher incidences of overall complication than cervical or lumbar surgery alone (p = 0.04 and p = 0.03, respectively). Median length of stay was 5 days for patients without a complication. Length of stay was significantly greater for patients with a minor complication (10 days, p < 0.0001) and even greater for patients with a major complication (14 days, p < 0.0001).

CONCLUSIONS

The incidence of complications found in this prospective analysis is higher than that reported in previous studies. This association may be due to a greater accuracy of record-keeping, absence of recall bias via prospective data collection, high complexity of pathology and surgical approaches, or application of a more liberal definition of what constitutes a complication. Further large-scale prospective studies using clear definitions of complication are necessary to ascertain the true incidence of early postoperative complications in spine surgery.

Obesity and spine surgery: reassessment based on a prospective evaluation of perioperative complications in elective degenerative thoracolumbar procedures

BACKGROUND CONTEXT

The correlation between obesity and incidence of complications in spine surgery is unclear, with some reports suggesting linear relationships between body mass index (BMI) and complication incidence and others noting no relationship.

PURPOSE

The purpose of this article was to assess the relationship between obesity and occurrence of perioperative complications in an elective thoracolumbar surgery cohort.

STUDY DESIGN/SETTING

Prospective observational cohort study at a tertiary care facility.

PATIENT SAMPLE

Cohort of 87 consecutive patients undergoing elective surgery for degenerative thoracolumbar pathologies over a 6-month period (May to December 2008).

OUTCOME MEASURES

Incidence of perioperative complications (those occurring within 30 days of surgery).

METHODS

A prospective assessment of perioperative spine surgery complications was completed, and data were prospectively entered into a central database. Two independent auditors assessed for the presence and severity of perioperative complications. Previously validated binary definitions of major and minor complications were used. Patient data and early complications (those occurring within 30 days of index surgery) were analyzed using multivariate regression.

RESULTS

Mean BMI in this cohort was 31.3; 40.8% of patients were obese (BMI>30) and 10 patients (11.5%) were morbidly obese (BMI>40). The overall complication incidence was 67%. Minor complications occurred in 50% of patients, and major complications occurred in 17.8% of patients. No positioning palsies occurred in this series. Age correlated with an increase in complication risk (p=.006) as did hypertension (p=.004) and performance of a fusion (p<.0001). BMI did not correlate with the incidence of minor, major, or any complications (p=.58).

CONCLUSIONS

This prospective assessment of perioperative complications in elective degenerative thoracolumbar procedures shows no relationship between patient BMI and the incidence of perioperative minor or major complications. Specific care in perioperative positioning may limit the risk of perioperative positioning palsies in obese patients.

Vascular injury in elective anterior lumbosacral surgery

STUDY DESIGN

Systematic review.

OBJECTIVE

To document the incidence and consequences of vascular injury in lumbosacral surgery, to identify factors contributing to this injury, and to determine whether there are any effective measures to decrease the occurrence of vascular injury.

SUMMARY OF BACKGROUND DATA

Anterior lumbosacral surgery encompasses all aspects of spine surgery, including trauma, deformity, and degenerative conditions. Although it has theoretical advantages, anterior lumbosacral surgery carries with it certain definite risks, one of the most critical of which is injury to the surrounding vasculature. It is important for both the patient and the surgeon to understand the risks, patterns, and outcomes of injury to the vascular structures associated with this surgery.

METHODS

A systematic review of the English-language literature was undertaken for articles published between January 1993 and December 2008. Electronic databases and reference lists of key articles were searched to identify published studies examining vascular injury in anterior lumbosacral surgery. Vascular injury was defined as any case in which a suture was required to control bleeding. Two independent reviewers assessed the strength of literature using the Grading of Recommendations Assessment, Development, and Evaluation criteria assessing quality, quantity, and consistency of results. Disagreements were resolved by consensus.

RESULTS

A total of 88 articles were initially screened, and 40 ultimately met the predetermined inclusion criteria. Vascular injuries after anterior lumbosacral surgeries were rare (<5%). Venous laceration was more common than arterial laceration, and most venous injuries occurred during retraction of the great vessels. In most cases, the overall clinical outcome after vascular injury was not adversely affected. L4-L5 exposure was associated with increased vascular injury in some studies but not others. Vascular injury occurred more frequently in laparoscopic compared with open anterior lumbar interbody fusion.

CONCLUSION

Vascular injury in anterior lumbosacral surgery remains low, with reports being <5%. The consequences of injury seem rare, but may include thrombosis, pulmonary embolism, and prolonged hospitalization. Exposure and surgery at L4-L5 may be associated with a higher risk of injury than that at L5-S1, though the data are not consistent.

Early outcomes and safety of the minimally invasive, lateral retroperitoneal transpsoas approach for adult degenerative scoliosis

Object

The object of this study was to evaluate an alternative surgical approach to degenerative thoracolumbar deformity in adults. The authors present their early experience with the minimally invasive, lateral retroperitoneal transpsoas approach for placing interbody grafts and providing anterior column support for adult degenerative deformity.

Methods

The authors retrospectively reviewed a prospectively acquired database of all patients with adult thoracolumbar degenerative deformity treated with the minimally invasive, lateral retroperitoneal transpsoas approach at our institution. All patient data were recorded including demographics, preoperative evaluation, procedure used, postoperative follow-up, operative time, blood loss, length of hospital stay, and complications. The Oswestry Disability Index and visual analog scale (for pain) were also administered pre- and postoperatively as early outcome measures. All patients were scheduled for follow-up postoperatively at weeks 2, 6, 12, and 24, and at 1 year.

Results

The authors identified 25 patients with adult degenerative deformity who were treated using the minimally invasive, lateral retroperitoneal transpsoas approach. All patients underwent discectomy and lateral interbody graft placement for anterior column support and interbody fusion. The mean total blood loss was 53 ml per level. The average length of stay in the hospital was 6.2 days. Mean follow-up was 11 months (range 3–20 months). A mean improvement of 5.7 points on visual analog scale scores and 23.7% on the Oswestry Disability Index was observed. Perioperative complications include 1 patient with rhabdomyolysis requiring temporary hemodialysis, 1 patient with subsidence, and 1 patient with hardware failure. Three patients (12%) experienced transient postoperative anterior thigh numbness, ipsilateral to the side of approach. In this series, 20 patients (80%) were identified who had more than 6 months of follow-up and radiographic evidence of fusion. The minimally invasive, lateral retroperitoneal transpsoas approach, without the use of osteotomies, did not correct the sagittal balance in approximately one-third of the patients.

Conclusions

Degenerative scoliosis of the adult spine is secondary to asymmetrical degeneration of the discs. Surgical decompression and correction of the deformity can be performed from an anterior, posterior, or combined approach. These procedures are often associated with long operative times and a high incidence of complications. The authors' experience with the minimally invasive, lateral retroperitoneal transpsoas approach for placement of a large interbody graft for anterior column support, restoration of disc height, arthrodesis, and realignment is a feasible alternative to these procedures.

High rectal injury during trans-1 axial lumbar interbody fusion L5-S1 fixation: a case report

STUDY DESIGN

A case report.

OBJECTIVE

To report a case of high rectal injury during trans-1 axial Lumbar Interbody Fusion (axiaLIF) L5-S1 fixation.

SUMMARY OF BACKGROUND DATA

Trans-1 axiaLIF procedure is gaining in popularity for L5-S1 fusion due to the ease of access to the sacrum through the presacral space. Normally, the midline of the sacrum at S1-S2 is relatively free from neurovascular and intra-abdominal structures, making this level a safe entry point for the axiaLIF procedure. We report a case of high rectal injury during Trans-1 axiaLIF L5-S1 procedure due to altered intra-abdominal anatomy as a result of multifactorial adhesions formation.

METHODS

A 44-year-old female patient with a history of previous anterior and posterior spinal surgeries, pelvic inflammatory disease, and non-disclosed previous diverticulitis, developed a high rectal injury during Trans-1 axiaLIF L5-S1 fixation.

RESULTS

After Trans-1 axiaLIF L5-S1, the patient presented with an episode of melena and hypogastric pain with nausea and vomiting. A computed tomography (CT) scan of the abdomen with intravenous and oral contrast showed presacral soft tissue fluid density with fat stranding and extraluminal rectal contrast and gas with some areas of soft tissue enhancement compatible with probable high rectal perforation. Patient's symptoms gradually subsided during a period of 6 months with aid from a temporary diverting ileostomy and a course of i.v. antibiotics. No spine implants were removed.

CONCLUSION

We report a case of high rectal injury during Trans-1 axiaLIF L5-S1 fixation and strongly advice that patients who are candidates for this surgery and have any risk factors for intra-abdominal adhesion formation, undergo a pelvic CT with rectal contrast before the surgery to evaluate for any signs of altered rectal-sacral anatomy.

Current trends in spinal arthroplasty: an assessment of surgeon practices and attitudes regarding cervical and lumbar disk replacement

STUDY DESIGN

Survey study involving orthopedic and neurosurgical spine surgeons.

OBJECTIVE

To report the current practices and opinions of spine surgeons regarding cervical and lumbar total disk arthroplasty (TDA) as alternatives to arthrodesis for the treatment of degenerative conditions of the spine.

SUMMARY OF BACKGROUND DATA

TDA represents an alternative surgical treatment for degenerative spinal conditions that may avoid the deleterious effects associated with fusion. Unfortunately, the prevailing opinions of surgeons about TDA have not been well characterized and the patterns of its utilization have not been documented previously in the literature.

METHODS

A questionnaire was developed to record the attitudes of spine surgeons regarding cervical and lumbar TDA and to assess their utilization of this technology. This survey was distributed to all of the surgeons attending the 2007 "Contemporary Update on Disorders of the Spine" meeting in Whistler, British Columbia.

RESULTS

One hundred thirteen of the 133 surgeons present at the meeting completed the questionnaire, corresponding to a return rate of 85%. The percentage of surgeons who had performed lumbar TDA was significantly higher than that for cervical TDA (42% vs. 30%, P=0.05). However, 81% of respondents stated that they were more likely to perform cervical TDA now compared with 1 year ago, whereas 64% indicated that they were less likely to perform lumbar TDA. The most frequently cited reasons for not performing both cervical and lumbar TDA were questions concerning long-term outcomes and perceived difficulties with obtaining financial compensation from insurance companies; in addition, surgeons were also concerned about revising lumbar TDA cases.

CONCLUSIONS

Although the results of this study confirm that the enthusiasm for TDA was shared by many of these respondents, it is clear that additional long-term, prospective, comparative data are required before this technology may be considered as a replacement for more traditional spinal fusion procedures.

Perioperative complications in revision anterior lumbar spine surgery: incidence and risk factors

STUDY DESIGN

This is a retrospective review of 129 consecutive anterior lumbar revision surgeries in 108 patients. It is a single-center, multi-surgeon study.

OBJECTIVE

To determine occurrence rates and risk factors for perioperative complications in revision anterior lumbar fusion surgery.

SUMMARY OF BACKGROUND DATA

Although complication rates from large series of primary anterior fusion procedures have been reported, reports of complication rates for revision anterior fusion procedures are relatively rare. Concern exists chiefly about the risk to vascular and visceral structures because of scar tissue formation from the original anterior exposure.

METHODS

This was a retrospective review of 129 consecutive anterior revision lumbar surgeries in 108 patients operated between 1998 and 2003. There were 40 men and 68 women. The age of patients ranged from 25 to 83 (average 50.6 years). Patients were excluded if surgery was for tumor or infection. Patients were divided into 2 groups; those with revision surgery at the same level and those with revision surgery at an adjacent level. Outcome measures included all perioperative complications. Statistical analysis included Student t test and nonparametric sign-rank.

RESULTS

The number of surgical levels treated for revision was similar between the 2 groups (1 level 69%; 2 levels 19%; 3 or more levels 12%). Revision cases at the same operative level had a higher overall complication rate (42%) compared with extensions (20%; P = 0.007). This difference was primarily because of vein lacerations (23.7% vs. 3.6%, P = 0.002). There were 2 ureteral problems, both successfully salvaged. There were no arterial injuries or deaths.

CONCLUSION

Complication rates for revision lumbar surgery in this series were 3 to 5 times higher than reported for primary lumbar exposures. Complication rates were significantly higher for revision anterior lumbar fusions at the same segment, which were typically in the lower lumbar spine, compared with cases involving extensions, which were typically in the upper lumbar spine.

Evaluation of Perivascular Adhesion Formation in New Zealand White Rabbits Using Oxiplex and DuraSeal Xact Adhesion Barrier System

Background

Adhesion formation after spine surgery is a result of normal wound healing that may place patients at increased risk for complications during revision surgery. Preventing adhesions could reduce the risk of complications during revision surgery, and possibly reduce the need for revision procedures. This study evaluates the ability of DuraSeal Xact Adhesion Barrier System (DSX) (Covidien, Mansfield, Massachusetts) and Oxiplex/SP gel (OX) (FzioMed, San Luis Obispo, California) to affect the extent and severity of postoperative perivascular adhesion development in an anterior spinal surgical rabbit model.

Methods

We determined the extent and severity of postoperative adhesion development 34 days after surgery in 12 male New Zealand White rabbits randomly assigned to intraoperative treatment with either DSX or OX, or to an untreated control group. Adhesion severity and extent were scored on scale from 0 (none) to 3 (severe).

Results

The extent and severity of adhesions in the DSX group were significantly less than in the untreated control group. The DSX group mean extent score was 1.3 ± 0.5 (vs 2.5, P = .01) and the mean severity score was 1.25 ± 0.5 (vs 2.8, P = .005). The extent and severity of adhesions in the OX group were not significantly different from the control group.

Conclusion

In this study, we found DSX to be the most effective compound in preventing adhesion formation after anterior spine surgery.

Clinical Relevance

Extrapolating these results in rabbits to humans, less scarring between the major blood vessels could decrease the rate of complications in revision spine procedures.

Cosmetic and functional outcomes following paramedian and anterolateral retroperitoneal access in anterior lumbar spine surgery

Object

In this paper, the authors review the functional and cosmetic outcomes and complications in 300 patients who underwent treatment for lumbar spine disease via either an anterior paramedian or conventional anterolateral retroperitoneal approach.

Methods

Seven surgeons performed anterior lumbar surgeries in 300 patients between August 2004 and December 2006. One hundred and eighty patients were treated with an anterior paramedian approach, and 120 patients with an anterolateral retroperitoneal approach. An access surgeon was used in 220 cases (74%). Postoperative evaluation in all patients consisted of clinic visits, assessment with the modified Scoliosis Research Society–30 instrument, as well as a specific questionnaire relating to wound appearance and patient satisfaction with the wound.

Results

At a mean follow-up of 31 months (range 12–47 months), the mean Scoliosis Research Society–30 score (out of 25) was 21.2 in the patients who had undergone the anterior paramedian approach and 19.4 in those who had undergone the anterolateral retroperitoneal approach (p = 0.005). The largest differences in quality of life measures were observed in the areas of pain control (p = 0.001), self-image (p = 0.004), and functional activity (p = 0.003), with the anterior paramedian group having higher scores in all 3 categories. Abdominal bulging in the vicinity of the surgical site was the most common wound complication observed and was reported by 22 patients in the anterolateral retroperitoneal group (18%), and 2 patients (1.1%) in the anterior paramedian group. Exposures of ≥ 3 levels with the anterolateral approach were associated with abdominal bulging (p = 0.04), while 1- or 2-level exposures were not (p > 0.05). Overall satisfaction with incisional appearance was higher in patients with an anterior paramedian incision (p = 0.001) and with approaches performed by an access surgeon (p = 0.004).

Conclusions

Patients who undergo an anterior paramedian approach to the lumbar spine have a higher quality of life and better cosmetic outcomes than patients undergoing an anterolateral retroperitoneal approach.

Computer-assisted surgical planning and image-guided surgical navigation in refractory adult scoliosis surgery: case report and review of the literature

STUDY DESIGN

Case report and literature review.

OBJECTIVE

In this case report, we present the utility of computer-assisted surgical planning and image-guided surgical navigation in the planning and execution of a major osteotomy to correct severe kyphoscoliosis.

SUMMARY OF BACKGROUND DATA

Computer-assisted surgical planning is useful to appreciate the three-dimensional nature of scoliotic deformities and allows for operative maneuvers to be simulated on a computer before their implementation in the operating room. Image-guided surgical navigation improves surgical accuracy and can help translate a virtual surgical plan to the operative setting.

METHODS

We report the case of a 38-year-old woman with severe, congenital kyphoscoliosis refractory to many previous surgeries, who presents with moderate progressive myelopathy and severe pain attributable to a sharp angular deformity at T12. Three-dimensional computed tomography reconstruction and computer-assisted surgical planning were used to determine the optimal corrective osteotomy. The surgical plan was translated to the operating room where a posterior vertebrectomy and instrumented correction were executed with the aid of image-guided surgical navigation.

RESULTS

The osteotomy was safely performed resulting in improved sagittal and coronal alignments, as well as, correction of the sharp kyphoscoliotic deformity at the thoracolumbar junction. At 6-month follow-up, the patient's myelopathy and pain had largely resolved and she expressed high satisfaction with the procedure.

CONCLUSION

We advocate this novel application of virtual surgical planning and intraoperative surgical navigation to improve the safety and efficacy of complex spinal deformity corrections.

Implications of lumbar plexus anatomy for removal of total disc replacements through a posterior approach

STUDY DESIGN

An anatomic study in which the lumbar plexuses of 14 embalmed cadavers were dissected bilaterally and measured using a posterior approach.

OBJECTIVE

To determine the cephalocaudal (root-to-root) distances and the mediolateral (root-to-tether) distances within the lumbar plexus and determine the feasibility for removal of a lumbar total disc replacement (TDR) through these anatomic spaces using a posterior approach.

SUMMARY OF BACKGROUND DATA

Currently, lumbar TDRs are implanted primarily through an anterior retroperitoneal or transperitoneal approach. However, revision surgeries through these approaches can be complicated by significant adhesions, with potential injuries to intra- and retroperitoneal contents. Advancements in accessing anterior column structures through a posterior lumbar extracavitary approach suggest that posterior removal of TDRs may be an alternative. Unlike the thoracic extracavitary approach in which ligation of the thoracic nerve rarely leaves significant morbidity, the lumbar extracavitary approach cannot rely on the analogous ligation of the lumbar root to achieve access. Therefore, feasibility of the lumbar extracavitary approach depends on the presence of sufficient anatomic space between the tethered nerves of the lumbar plexus.

METHODS

Fourteen adult cadavers (5 M/9F) were dissected through a posterior approach to expose the lumbar plexus bilaterally. The root-to-root distances at levels L2-S1 and corresponding root-to-tether distances at levels L3-L5 were measured bilaterally.

RESULTS

Root-to-root distance was smallest at the male L5-S1 interval (11.7 +/- standard deviations 4.1 mm). Root-to-tether distance was smallest at the female L5 (43.1 +/- standard deviations 8.4 mm). These plexus measurements compare favorably with the CHARITE TDR components, in which the thickest sliding core is 11.0 mm in height and the largest endplate is 42.0 mm in width.

CONCLUSION

This anatomic study suggests that posterior TDR removal is possible in the lumbar spine without undue risk to the surrounding nervous structures.