Partially overlapping limited anterior and posterior instrumentation for adult thoracolumbar and lumbar scoliosis: a description of novel spinal instrumentation, "the hybrid technique"

Complications and Unfavorable Clinical Outcomes in Obese and Overweight Patients Treated for Adult Lumbar or Thoracolumbar Scoliosis With Combined Anterior/Posterior Surgery

BACKGROUND CONTEXT

Combined anterior/posterior (A/P) spinal fusion with instrumentation has been used for many years in the treatment of adult thoracolumbar and lumbar (TL/L) scoliosis. However, the risk factors for complications and poor clinical outcomes with this procedure are not well known.

PURPOSE

To assess the risk factors for poor clinical outcomes in a series of adult lumbar or scoliosis patients undergoing combined A/P-instrumented spinal fusion.

STUDY DESIGN

This study was a retrospective case series of surgically treated adult lumbar or thoracolumbar scoliosis patients.

PATIENT SAMPLE

From 1998 to 2006, 57 patients with diagnoses of adult idiopathic scoliosis or degenerative TL/L scoliosis underwent combined A/P spinal instrumentation and fusion at 1 institution, performed by 1 senior author.

OUTCOME MEASUREMENTS

The preoperative and postoperative outcome measurements included self-report measurements, physiological measurements, and functional measurements.

MATERIALS AND METHODS

A retrospective review of this patient group was performed to evaluate patient satisfaction, functional outcomes, pain, curve progression, and complications. Radiographic measurements included coronal balance, sagittal vertical axis, Cobb angle, thoracic kyphosis, lumbar lordosis, and pelvic incidence preoperatively, immediately postoperatively, and during follow-up. In terms of risk factors, bone mineral density, body mass index, age, kyphosis, and fusion to the sacrum were reviewed. Postoperative Scoliosis Research Society Patient Questionnaire outcome scores, Oswestry Disability Index (ODI), and anterior surgical site pain (ASSP) were also evaluated. Means were compared with the Student t test and the χ test. Logistic regression analyses were used to predict the probabilities and the odds ratios (ORs) of the risk factors for poor clinical outcomes. A P-value of <0.05 with a confidence interval of 95% was considered significant.

RESULTS

Fifty patients had adult idiopathic scoliosis, and 7 patients had degenerative scoliosis. The average age at surgery was 53.8 years (34-74 y), and the average follow-up was 4.8 years (2-11 y). Coronal correction for thoracic, thoracolumbar, and lumbosacral curves improved significantly. The degree of sagittal curve and coronal and sagittal balance were not significantly changed after surgery or at the final follow-up. ODI, the pain intensity domain of the ODI, and ASSP were significantly worse in obese and overweight patients, whereas OR time, estimated blood loss, and number of fused vertebrae were not different in the entire group (P=0.03 for ODI, P=0.002 for pain domain of ODI, and P=0.003 for ASSP). Logistic regression analyses for the risk factors of poor clinical outcomes indicated obesity and overweight as risk factors for poor clinical outcomes (OR=6.25 for ODI and 5.88 for ODI pain intensity score). A significantly higher rate of major complications occurred in this group compared to the entire group (30.4%, P=0.04). Low bone mineral density, old age, kyphosis, and fusion to the sacrum were not risk factors for poor clinical outcomes.

CONCLUSIONS

Despite the good function scores and acceptable pain levels in most patients, the ODI scores of obese and overweight patients were worse compared to the rest of the patients in this study. Significantly worse scores on the pain intensity domain of the ODI and ASSP differences were likely caused by extensive dissection of the abdominal wall and psoas muscles and the technical difficulty of achieving an anterior approach to the thoracolumbar spine. Radiographs revealed no progression of the TL/L curves. This study indicates that obesity and overweight are potential risk factors for combined A/P-instrumented spinal fusion in patients with adult TL/L scoliosis, perhaps due to the technical difficulty of achieving an anterior approach to the thoracolumbar spine.

A Comprehensive Review of Complication Rates After Surgery for Adult Deformity: A Reference for Informed Consent

OBJECTIVE

An up-to-date review of recent literatures and a comprehensive reference for informed consent specific to ASD complications is lacking. The goal of the present study was to determine current complication rates after ASD surgery, in order to provide a reference for informed consent as well as to determine differences between three-column and non-three-column osteotomy procedures to aid in shared decision making.

METHODS

A review of the literature was conducted using the PubMed database. Randomized controlled trials, nonrandomized trials, cohort studies, case-control studies, and case series providing postoperative complications published in 2000 or later were included. Complication rates were recorded and calculated for perioperative (both major and minor) and long-term complication rates. Postoperative outcomes were all stratified by surgical procedure (ie, three-column osteotomy and non-three-column osteotomy).

RESULTS

Ninety-three articles were ultimately eligible for analysis. The data of 11,692 patients were extracted; there were 3,646 complications, mean age at surgery was 53.3 years (range: 25-77 years), mean follow-up was 3.49 years (range: 6 weeks-9.7 years), estimated blood loss was 2,161 mL (range: 717-7,034 mL), and the overall mean complication rate was 55%. Specifically, major perioperative complications occurred at a mean rate of 18.5%, minor perioperative complications occurred at a mean rate of 15.7%, and long-term complications occurred at a mean rate of 20.5%. Furthermore, three-column osteotomy resulted in a higher overall complication rate and estimated blood loss than non-three-column osteotomy.

CONCLUSIONS

A review of recent literatures providing complication rates for ASD surgery was performed, providing the most up-to-date incidence of early and late complications. Providers may use such data in helping to counsel patients of the literature-supported complication rates of such procedures despite the planned benefits, thus obtaining a more thorough informed consent.

Adult thoracolumbar and lumbar scoliosis treated with long vertebral fusion to the sacropelvis: a comparison between new hybrid selective spinal fusion versus anterior-posterior spinal instrumentation

BACKGROUND CONTEXT

Combined anteroposterior spinal fusion with instrumentation has been used for many years to treat adult thoracolumbar/lumbar scoliosis. This surgery remains a technical challenge to spine surgeons, and current literature reports high complication rates.

PURPOSE

The purpose of this study is to validate a new hybrid technique (a combination of single-rod anterior instrumentation and a shorter posterior instrumentation to the sacrum) to treat adult thoracolumbar/lumbar scoliosis.

STUDY DESIGN

This study is a retrospective consecutive case series of surgically treated patients with adult lumbar or thoracolumbar scoliosis.

PATIENT SAMPLE

This is a retrospective study of 33 matched pairs of patients with adult scoliosis who underwent two different surgical procedures: a new hybrid technique versus a third-generation anteroposterior spinal fusion.

OUTCOME MEASURES

Preoperative and postoperative outcome measures include self-report measures, physiological measures, and functional measures.

METHODS

In a retrospective case-control study, 33 patients treated with the hybrid technique were matched with 33 patients treated with traditional anteroposterior fusion based on preoperative radiographic parameters. Mean follow-up in the hybrid group was 5.3 years (range, 2-11 years), compared with 4.6 years (range, 2-10 years) in the control group. Operating room (OR) time, estimated blood loss, and levels fused were collected as surrogates for surgical morbidity. Radiographic parameters were collected preoperatively, postoperatively, and at final follow-up. The Scoliosis Research Society Patient Questionnaire (SRS-22r) and Oswestry Disability Index (ODI) scores were collected for clinical outcomes.

RESULTS

Operating room time, EBL, and levels fused were significantly less in the hybrid group compared with the control group (p<.0001). The postoperative thoracic Cobb angle was similar between the hybrid and control techniques (p=.24); however, the hybrid technique showed significant improvement in the thoracolumbar/lumbar curves (p=.004) and the lumbosacral fractional curve (p<.0001). The major complication rate was less in the hybrid group compared with the control group (18% vs. 39%, p=.01). Clinical outcomes at final follow-up were not significantly different based on overall SRS-22r scores and ODI scores.

CONCLUSION

The new hybrid technique demonstrates good long-term results, with less morbidity and fewer complications than traditional anteroposterior surgery select patients with thoracolumbar/lumbar scoliosis. This study received no funding. No potential conflict of interest-associated bias existed.

Long-term 2- to 5-year clinical and functional outcomes of minimally invasive surgery for adult scoliosis

STUDY DESIGN

A retrospective study.

OBJECTIVE

We assess MIS technique's clinical and functional outcomes during a 2- to 5-year period.

SUMMARY OF BACKGROUND DATA

Traditional surgical approaches for adult scoliosis are associated with significant blood loss and morbidity, in a population that is often elderly with multiple medical comorbidities. Minimally invasive surgery (MIS) represents a newer method of achieving similar long-term outcomes but considerably lower morbidity and complication rates.

METHODS

We reviewed 71 patients who underwent MIS correction of spinal deformity with fusion of 2 or more levels including: degenerative scoliosis (54), idiopathic scoliosis (11), and iatrogenic scoliosis (6). All underwent a combination of 3 MIS techniques: direct lateral interbody fusion (66), axial lumbar interbody fusion (34), and posterior instrumentation (67). Thirty-six patients were staged with direct lateral interbody fusion done first followed by the posterior instrumentation and fusion including axial lumbar interbody fusion done 3 days later.

RESULTS

Mean age was 64 years (20-84 yr). Mean follow-up was 39 months (24-60 mo). Patients with 1-stage same-day surgery had a mean blood loss of 412 mL and a mean surgical time of 291 minutes. Patients with 2-stage surgery had a mean blood loss of 314 mL and surgical time of 183 minutes for direct lateral interbody fusion and 357 mL and 243 minutes, respectively for posterior instrumentation and axial lumbar interbody fusion. Mean hospital stay was 7.6 days (2-26 d). The mean preoperative Cobb angle was 24.7° (8.3°-65°), which corrected to 9.5° (0.6°-28.8°). Mean preoperative Coronal balance was 25.5 mm, which corrected to 11 mm. Mean preoperative sagittal balance was 31.7 mm and corrected to 10.7 mm. The mean preoperative lumbar apical vertebral translation was 24 mm and corrected to 12 mm. Fourteen patients had adverse events requiring intervention: 4 pseudarthrosis, 4 persistent stenosis, 1 osteomyelitis, 1 adjacent segment discitis, 1 late wound infection, 1 proximal junctional kyphosis, 1 screw prominence, 1 idiopathic cerebellar hemorrhage, and 2 wound dehiscence.

CONCLUSION

A combination of 3 novel MIS techniques allows comparable correction of adult spinal deformity, with low pseudarthrosis rates, significantly improved functional outcomes, and excellent clinical and radiological improvement, but considerably lowers morbidity and complication rates at early and long-term follow-up.

Incidence, risk factors and classification of proximal junctional kyphosis: surgical outcomes review of adult idiopathic scoliosis

STUDY DESIGN

Retrospective case series of surgically treated adult scoliosis patients.

OBJECTIVE

To assess the incidence, risk factors and clinical outcomes of proximal junctional kyphosis (PJK) in a large series of adult idiopathic scoliosis patients undergoing long instrumented spinal fusion (.5 vertebrae). A new classification is also projected.

SUMMARY OF BACKGROUND DATA

Maintaining both coronal and sagittal balance is essential in the surgical treatment of adult deformity patients. PJK is a well-recognized postoperative phenomenon in adults and adolescents after scoliosis surgery. Despite recent reports, the prevalence, clinical outcomes, and the risk factors of PJK are still controversial.

MATERIALS AND METHODS

This study is a retrospective review of the charts and radiographs of 157 consecutive patients with adult scoliosis treated with long instrumented spinal fusion. PJK was defined by a proximal junctional angle greater than 108 and at least 108 greater than the corresponding preoperative measurement. Radiographic measurements included sagittal vertical axis (SVA), thoracic kyphosis (TK), lumbar lordosis (LL) and pelvic incidence (PI) on preoperative, immediate postoperative and at follow-up. Bone mineral density (BMD), Body mass index (BMI), age, sex, instrumentation type, surgery type, and fusion to sacrum were reviewed. Postoperative SRS outcome scores and Oswestry Disability Index (ODI) were also evaluated. PJK was graded by the severity and type. Means were compared with Student's t test and χ2 test. P value of less than 0.05 with confidence interval 95% was considered significant.

RESULTS

The average age was 46.9 years (22-81 years) and the average Follow-up was 4.3 years (2-12 years). PJK occurred in 32 patients (20%) and were mostly classified as 1A (Ligamentous & mild) deformity. The SRS outcome scores and ODI did not demonstrate significant differences between PJK group and non-PJK group, four patients had additional surgeries performed for local pain. Fusion to the sacrum and posterior fusion with segmental instrumentation were significant risk for PJK (P = 0.03, P < 0.01). BMD, BMI, age, sex, and instrumentation type showed no difference. Eighty-four percent of PJK group was associated with TK 1 LL 1 PI .458 or preoperation to postoperation SVA more than 50 mm vs. 6.4% of non-PJK group (P < 0.01, P < 0.01).

CONCLUSION

Despite the occurrence of PJK in 20% of adult scoliosis patients undergoing long fusion, no significant differences were found in SRS outcome scores and ODI in PJK and non-PJK patients. Fusion to the sacrum and posterior fusion with segmental instrumentation were identified as risk factors. PJK can be minimized by post-operative normalization of global sagittal alignment. A simplified classification based in severity type of PJK showed the majority in class 1A (ligamentous lesion and mild deformity).