Intraoperative skull-femoral traction in posterior spinal arthrodesis for adolescent idiopathic scoliosis: the impact on perioperative outcomes and health resource utilization

Risk factors for neurophysiological events related to intraoperative halo-femoral traction in spinal deformity surgery

PURPOSE

This study identifies risk factors for neurophysiological events caused by intraoperative halo-femoral traction (IOHFT) in patients with adolescent idiopathic scoliosis (AIS), and neuromuscular scoliosis (NMS).

METHODS

Neurophysiological integrity was monitored using motor evoked potentials (MEPs). IONM event was defined as a decreased MEP amplitude of more than 80% of baseline in, at least, one muscle. Time between application of IOHFT and event, affected muscles, surgical stage, and time between removal of IOHFT and recovery of MEPs were described. Characteristics (age, height, weight, diagnosis, Cobb angle, and flexibility of the curve) of patients with and without IOHFT-events were compared using analysis of variance. Binary logistic regression analyses were performed to identify predictors.

RESULTS

The study included 81 patients (age 15.6 ± 2.4 years, 53 females, AIS: n = 47, NMS n = 34). IOHFT-events occurred in 11 patients (13%; AIS n = 4, NMS n = 7). IOHFTevents affecting all limbs occurred pre-incision in NMS. Events affecting only the legs occurred during all stages of surgery. Patients with IOHFT-events were smaller (p = 0.009) and had stiffer curves (p = 0.046). Height was a predictor (odds ratio, 0.941; 95% confidence interval = 0.896-0.988). All MEPs recovered after removing IOHFT.

CONCLUSION

Neurophysiologic events due to IOHFT were common, with the majority in patients with NMS. A shorter stature was a risk factor, and larger Cobb angle and stiffer curve were associated with IOHFT-events. Events occurred at any stage of surgery and involved upper and lower limbs. With an adequate response on IOHFT events, none of the patients had postoperative neurological impairments due to IOHFT.

What is the effect of intraoperative traction on correction of adolescent idiopathic scoliosis (AIS)?

PURPOSE

Determine the efficacy of intraoperative traction (IOT) on curve correction in AIS.

METHODS

A prospective, multicenter, longitudinal database identified patients with major thoracic AIS (Lenke 1-4) treated with surgery using IOT and follow-up of 2 years. These cases were matched to comparable cases treated without traction (non-IOT). All patients were treated with single-stage posterior only surgery with pedicle screw constructs. Perioperative, radiographic and clinical outcome data at 2 years post-op were compared between the groups.

RESULTS

104 cases treated with IOT were matched to 104 treated without IOT. Operating room time was significantly greater in the IOT group (339 vs. 306 min, p =  < 0.001). Neuromonitoring alerts were more frequent in the IOT group (23% vs. 5%, p < 0.001). There were no postoperative neurological deficits in either group. The IOT group showed significantly greater MT curve correction (IOT 71% vs. non-IOT 66.7%, p < 0.003), with the effect most pronounced in curves > 70° (IOT 72% vs. non-IOT 64%, p = 0.04). IOT was associated with a significant reduction in 2D T5-T12 kyphosis measurements (IOT - 6.5° vs non-IOT + 0.48°, p < 0.001), yet significant improvements in estimated 3D thoracic kyphosis were made in both groups, with the non-IOT group making greater improvement when compared to the IOT group (IOT + 18.1° vs. non-IOT + 22.3° vs., p = 0.008).

CONCLUSIONS

IOT is associated with modestly enhanced coronal deformity correction. Surgeons should be aware of the increased rates of neuromonitoring alerts when using this technique and its affect on the sagittal profile. Given this IOT may be best suited to larger curves.

LEVEL OF EVIDENCE

3.

Intraoperative halo-femoral traction during posterior spinal arthrodesis for adolescent idiopathic scoliosis curves between 70° and 100°: a randomized controlled trial

OBJECTIVE

Surgical management of scoliosis curves between 70° and 100° remains controversial. The authors designed this randomized controlled trial to validate the efficacy of intraoperative halo-femoral traction (IOHFT) in patients with adolescent idiopathic scoliosis (AIS), Cobb angles between 70° and 100°, and flexibility < 35%.

METHODS

The authors prospectively recruited and randomized 29 patients with severe AIS scheduled for posterior surgery into a traction group or control (nontraction) group. The primary outcome measures were operative time, blood loss, and length of hospital stay. Secondary outcomes included degree of spine deformity correction, traction-related complications, and health-related quality of life.

RESULTS

In the traction group, the average preoperative Cobb angle was 83.2°, with an average 20.6% flexibility. The average postoperative Cobb angle was 16.1° and the major curve was 18.3° at the final follow-up. In the control group, the average preoperative major curve was 80.3° with 22.8% flexibility. The average postoperative Cobb angle was 16.1° and the major curve was 18.1° at the final follow-up. The operative duration was 325.7 minutes for the traction group and 385.4 minutes for the control group (p = 0.018). Compared with the control group, the traction group had a 29.5% reduction in intraoperative blood loss and a significantly lower rate of blood transfusion (13.3% vs 50.0%, p = 0.033). There were no neurological complications in either group. One patient in the traction group had a superficial infection at the traction site.

CONCLUSIONS

Use of IOHFT contributed to significant reductions in operative time and blood transfusion requirements, with no added morbidity. It is an effective and safe method to assist correction of AIS curves between 70° and 100° and flexibility < 35%.

Operative time in adolescent idiopathic scoliosis surgery: a need for a standard definition

Our objective is to report and define 'operative time' in adolescent idiopathic scoliosis (AIS) posterior spinal fusion surgeries. Documenting key times during surgery are important to compare operative risks, assess learning curves, and evaluate team efficiency in AIS surgery. 'Operative time' in literature has not been standardized. Systematic review was performed by two reviewers. Keywords included operative time, duration of surgery, and scoliosis. One thousand nine hundred six studies were identified, 1092 duplicates were removed and 670 abstracts were excluded. Of the 144 articles, 67 met inclusion and exclusion criteria. Studies were evaluated for number of patients, operative time, and definition of operative time. Meta-analysis was not performed due to confounders. Of the 67 studies (6678 patients), only 14 (1565 patients) defined operative time, and all specified as incision to closure. From these 14 studies, the median operative time was 248 minutes (range 174-448 minutes). In the 53 studies (5113 patients) without a definition, one study reported time in a non-comparable format, therefore, data were analyzed for 52 studies (5078 patients) with a median operative time of 252 minutes (wider range 139-523 minutes). A clear standardized definition of operative or surgical time in spine surgery does not exist. We believe that operative time should be clearly described for each published study for accurate documentation and be defined from incision time to spine dressing completion time in order to standardize study results. Level of evidence: IV.

Intraoperative traction in neuromuscular scoliosis surgery improves major curve correction when fusing to L5

BACKGROUND

Intraoperative traction has shown improved curve correction in neuromuscular scoliosis surgery. It is found to be superior to anterior release in terms of correction of both main curve and pelvic obliquity. No previous study has examined the effect of intraoperative traction in patients without pelvic fixation.

METHOD

This retrospective study included 40 non-ambulatory (GMFCS 4 or above) patients with neuromuscular scoliosis undergoing surgery with bilateral segmental pedicle screw instrumentation to L5. Twenty-two consecutive patients had intraoperative Gardner-Wells tongs and skin traction (traction group), while the remaining did not (non-traction group). Inclusion criteria were minimum 2-year follow-up, complete medical records and radiographs. Main curve (MC), pelvic obliquity (POB), T1 tilt, kyphosis, rotation, coronal and sagittal balance and preoperative bending radiographs were measured and analyzed in all patients.

RESULTS

Both groups demonstrated roughly 60% MC correction. Preoperative MC was larger in the traction group [97° (49-126) vs. 83° (40-134); P = 0.03]. The measured correction index was almost twice as large in the traction group (1.9 vs. 1.1; P = 0.001). Mean [IQR] 2-year POB was 14° [7-40] in the traction group compared to 16° [4-60] in the non-traction group (P = 0.59). Eleven patients (50%) in the traction group compared to only four (22%) in the non-traction group had a POB within 10° at 2-year follow up (RR: 2.1; 95% CI 0.8-5.2). We found no difference in kyphosis or remaining radiographic parameters. No traction-related complications were recorded.

CONCLUSION

In patients with neuromuscular scoliosis undergoing instrumented fusion to the L5, we found that intraoperative traction increased the degree of MC correction and patients were more likely to achieve POB below 10° without any effects on sagittal parameters or without any detectable significant reduction on rotation.

The Association Between the Utilization of Traction and Postoperative Complications Following Growing Rod Instrumentation for Early-onset Scoliosis

BACKGROUND

Preoperative and/or intraoperative traction have been proposed as adjunctive methods to limit complications associated with growth-friendly instrumentation for early-onset scoliosis (EOS). By gradually correcting the deformity before instrumentation, traction can, theoretically, allow for better overall correction without the complications associated with the immediate intraoperative correction. The purpose of this multicenter study was to investigate the association between preoperative/intraoperative traction and complications following growth-friendly instrumentation for EOS.

METHODS

Patients with EOS who underwent growth rod instrumentation before 2017 were identified from 2 registries. Patients were divided into 2 groups: preoperative traction group versus no preoperative traction group. A subgroup analysis was done to compare intraoperative traction only versus no traction. Data was collected on any postoperative complication from implantation to up to 2 years postimplantation.

RESULTS

Of 381 patients identified, 57 (15%) and 69 (18%) patients received preoperative and intraoperative traction, respectively. After adjusting for etiology and degree of kyphosis, there was no evidence to suggest that preoperative halo traction reduced the risk of any complication following surgical intervention. Although not statistically significant, a subgroup analysis of patients with severe curves demonstrated a trend toward a markedly reduced hardware failure rate in patients undergoing preoperative halo traction [preoperative traction: 1 (3.1%) vs. no preoperative traction: 11 (14.7%), P=0.083]. Nonidiopathic, hyperkyphotic patients treated with intraoperative traction were 61% less likely to experience any postoperative complication (P=0.067) and were 74% (P=0.091) less likely to experience an unplanned return to the operating room when compared with patients treated without traction.

CONCLUSIONS

This multicenter study with a large sample size provides the best evidence to date of the association between the use of traction and postoperative complications. Our results justify the need for future Level I studies aimed at characterizing the complete benefit and risk profile for the use of traction in surgical intervention for EOS.

LEVEL OF EVIDENCE

Level III.

Sagittal Balance in Adolescent Idiopathic Scoliosis Managed With Intraoperative Skull Femoral Traction

STUDY DESIGN

This is a retrospective cohort, single-center quality improvement study.

OBJECTIVES

To evaluate the effect of the intraoperative skull femoral traction (IOSFT) on sagittal balance in posterior spinal instrumentation (PSI) to manage scoliosis.

SUMMARY OF BACKGROUND DATA

IOSFT has been used routinely as an adjunct technique for facilitating PSI to manage scoliosis in our institution since 2010. Previous studies have raised concerns regarding the negative effect of IOSFT on lumbar lordosis.

MATERIALS AND METHODS

The medical records and radiographs of 113 patients with adolescent idiopathic scoliosis managed with single stage PSI were reviewed. Eighty-five patients were operated with IOSFT (traction group) and 28 patients were operated without traction (nontraction group). Patients who had double (anterior-posterior) approaches or nonidiopathic scoliosis were excluded. Sagittal balance and pelvic parameters at 2 years of postoperative follow-up were the primary outcome measures. Statistical analysis was done with R for statistical computing. Median values and interquartile range were compared between groups using Wilcoxon rank sum, Fischer exact, and Welch t tests. P-values of <0.05 were considered statistically significant.

RESULTS

No significant differences were found comparing postoperative lumbar lordosis in the nontraction group (54 degrees) with the traction group (53 degrees) (P=0.4953). No significant differences were found in postoperative sagittal vertical axis medians comparing both groups, with 17 mm in the nontraction group and 18 mm in the traction group (P=0.3994). No significant differences were found in postoperative pelvic parameters. The median pelvic incidence was 52 degrees in the nontraction group and 50 degrees in the traction group (P=0.2711).

CONCLUSIONS

According to our results, the use of IOSFT as an adjunct to facilitate PSI for managing adolescent idiopathic scoliosis had no measurable negative impact on sagittal balance in our IOSFT cohort.

Reinventing the wheel in scoliosis surgery: effective strategies for safely improving efficiency

Posterior spinal instrumentation and fusion (PSIF) has been the standard operative treatment for adolescent idiopathic scoliosis (AIS) and is one of the most frequently performed elective pediatric surgeries in North America, incurring an expenditure of more than $1.1 billion annually in the United States alone. This commentary reflects on the outcomes of systematically implementing intraoperative skull femoral traction (IOSFT) combined with navigated sequential drilling (NSD) during PSIF for AIS as strategies for quality improvement at our tertiary children’s hospital.

Quality, Safety, and Value of Innovating Classic Operative Techniques in Scoliosis Surgery: Intraoperative Traction and Navigated Sequential Drilling

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

This study aims to measure and describe the clinical and financial implications of the systematic implementation of intraoperative skull-femoral traction (IOSFT) and navigated sequential drilling (NSD) for posterior spinal instrumentation and fusion (PSIF) in adolescent idiopathic scoliosis (AIS) at our institution.

SUMMARY OF BACKGROUND DATA

PSIF has been the standard surgical treatment for AIS. This retrospective single-center quality improvement study describes the perioperative outcomes and impact on health resource utilization following the systematic application of two classic surgical strategies modified using current technology: IOSFT and NSD.

METHODS

We reviewed the medical records of 125 patients who underwent a single-stage PSIF for AIS. We identified three cohorts based on surgical strategies used intraoperatively. Traditional techniques (n = 28), IOSFT (n = 45), and IOSFT plus NSD (n = 52). The primary outcome measures were operative time, prevalence of cases requiring extended operating room time, need for blood transfusion, length of hospital stay, and cost per surgery. Secondary outcomes included implant density, degree of spine deformity correction, and perioperative complications.

RESULTS

All primary outcome measures improved significantly (p < .001). Median operating time decreased by 59%. Use of late operating room hours fell from 89% to 0% and transfusion rates from 64% to 1.9%. Length of hospital stay decreased from 6 to 4 days. Comprehensive cost per case decreased by 24%.

DISCUSSION

Together, IOSFT and NSD improved the quality, safety, and value of care. These surgical strategies were performed without increased perioperative complications, while reducing cost per case by 24%.

CONCLUSIONS

The data presented may have significant implications in health resource utilization for AIS surgery.

LEVEL OF EVIDENCE

Level III.

Skull-femoral traction after posterior release for correction of adult severe scoliosis: efficacy and complications

Background

It is a great challenge for spine surgeons to correct severe rigid scoliosis. We developed a three- staged correction (one stage posterior release and screw placement, two stage skull-femoral traction and three stage posterior instrumentation) for adult severe scoliosis. The objective of this study is to investigate safety and efficacy of a three- staged correction for adult severe scoliosis.

Methods

A retrospective review was performed for patients with severe scoliosis receiving three- staged correction (one stage posterior release and screw placement, two stage skull-femoral traction and three stage posterior instrumentation) from June 2001 to October 2014. The inclusion criteria were as follows: [1] age more than 18 years; [2] main curve larger than 90°; [3] a minimum 2-year follow-up. Patients were excluded if they had a history of surgery or anterior release or receiving three column osteotomies.

Results

A total of 63 patients were included (37 female and 26 male), with a mean age of 22.7 years (range: 18–30 years) and follow-up of 42.6 months (range: 24–108 months). The aetiology was congenital in 27 patients, neuromuscular in 18, idiopathic in 11, neurofibromatosis-1 in 4 and Marfan syndrome in 3. The mean traction weight was 28.4 kg (range: 18–32 kg), equal to 57.2% of patients’ body weight (range: 42.7–72.3%). The mean traction time was 22.7 days (range: 12–44 days). Postoperative correction rate was 55% (range: 38–78%) for scoliosis and 51% (range: 32–75%) for kyphosis. Contribution of traction to correction was 51% (range: 36–70%) for scoliosis and was 43% (range: 34–55%) for kyphosis.

Conclusions

Three- staged correction (one stage posterior release and screw placement, two stage skull-femoral traction and three stage posterior instrumentation) could effectively correct adult severe scoliosis. The incidence of complications of skull-femoral traction was not low, but transient and could be successfully managed.

Hemolysis Following Intraoperative Cell Salvage Replacement in a Scoliosis Patient With Sickle Cell Trait: A Case Report

MINI: Intraoperative cell salvage (ICS) is used to reduce blood loss in scoliosis spinal fusion. We report one case of hemolysis induced acute renal failure following ICS. This is the first reported case of acute renal failure associated with hemolysis following ICS in a scoliosis patient with sickle cell trait.

STUDY DESIGN

Case report.

OBJECTIVE

To describe a novel presentation of acute renal failure associated with hemolysis after intraoperative cell salvage (ICS) in a neuromuscular scoliosis patient with sickle cell trait (SCT).

SUMMARY OF BACKGROUND DATA

Hemolysis-associated acute renal failure after ICS in patients with SCT has not been previously reported. Sickle cell disease is regarded as a relative contraindication for ICS due to the risk of red blood cell sickling in the hypoxic cell saver reservoir. A previous case series demonstrated successful ICS reinfusion after elective caesarean section in two patients with SCT. However, a decision to not reinfuse ICS collected blood due to increased sickling after blood processing was reported in general surgery.

METHODS

A 14-year-old female with Group I neuromuscular scoliosis underwent a navigated T3-S1posterior spinal instrumentation fusion. Three hundred milliliters of blood collected by ICS was reinfused intraoperatively along with two units of packed red blood cells.

RESULTS

Postoperatively, the patient had delayed emergence from the general anesthetic and gross hematuria was observed in the urinary catheter bag. The patient was transferred to the intensive care unit and was treated successfully for hemolysis-induced renal failure.

CONCLUSION

Given the potential seriousness of hemolysis-associated acute renal failure associated with ICS, we recommend against the use of ICS in patients with SCT.

LEVEL OF EVIDENCE

5.