Nine-year mean follow-up of one-stage anteroposterior excision of hemivertebrae in the lumbosacral spine

Posterior concave reconstruction with cage in the surgical treatment of complex lumbar deformity caused by lumbosacral hemivertebrae

PURPOSE

To identify the clinical and radiological outcomes in the coronal and sagittal planes after treatment of congenital complex lumbosacral hemivertebrae (LSHV) with or without posterior concave reconstruction.

METHODS

We retrospectively reviewed a consecutive series of patients with congenital LSHV deformities treated by posterior-only hemivertebra resection. The minimum follow-up was 2 years. The patients were divided into a concave-cage group and a non-cage group. The radiographic and clinical results were compared between the two groups.

RESULTS

Forty patients were categorized into the cage group (n = 14) and non-cage group (n = 26). At the end of the propensity score matching analysis, 14 patients from the cage group were matched to 14 patients in the non-cage group. The lumbosacral curve and thoracolumbar/lumbar curve improved significantly in both groups at the final postoperative follow-up (P < 0.001), and the lumbosacral curve at the final follow-up was remarkably lower in the cage than non-cage group. The correction rates of the lumbosacral curve and thoracolumbar/lumbar curve were significantly higher in the cage than non-cage group. The lower lumbar lordosis improved significantly in both groups at the final postoperative follow-up (P < 0.05), and the lower lumbar lordosis at the final follow-up and its correction were remarkably higher in the cage than non-cage group (both P < 0.05).

CONCLUSIONS

Posterior column reconstruction with insertion of a concave cage may achieve a higher correction rate of large lower lumbar lordosis and lumbosacral coronal deformity, attain better sagittal balance, and have fewer complications related to implant failure than posterior-only hemivertebra resection in patients with congenital LSHV.

Failure of Posterior Lower Lumbar/Lumbosacral Hemi-Vertebra Resection: An Analysis of Reasons and Revision Strategies

OBJECTIVE

To investigate the causes of failed primary surgery and the revision strategies for congenital scoliosis (CS) patients with lower lumbar/lumbosacral (LL/LS) hemi-vertebra (HV).

METHODS

Fifteen CS patients with LL/LS HV (seven females and eight males) with a mean age of 20.4 ± 10.4 years undergoing revision surgery in our center were retrospectively reviewed. The radiographic parameters including Cobb angle, distance between C₇ plumb line and center sacral vertical line (C₇ PL-CSVL), thoracic kyphosis (TK), lumbar lordosis (LL) and sagittal vertical axis (SVA) were assessed at pre-revision, post-revision and the last follow-up. The causes of failure in primary operation, and radiographic and clinical outcomes of revision procedures were analyzed.

RESULTS

The revision rate of patients undergoing LL/LS HV resection and correction surgery was 11.4%. The average time interval between primary surgery and revision surgery was 18.2 ± 10.6 months. The operation duration and estimated blood loss of revision surgery were 194 ± 56 min and 326 ± 74 ml, respectively. Reasons for failed primary operations were as follows: internal fixation fracture in 10 cases, curve progression in two cases, implant loose in two cases and post-operative coronal imbalance in one case. The post-revision Cobb angle was significantly improved from 29.9° ± 8.3° to 18.7° ± 6.7° (P < 0.001) with a correction rate of 37.5% ± 12.6%. At the final follow-up, the average Cobb angle was 18.9° ± 6.2° and the correction was well maintained (P = 0.788). The C₇ PL-CSVL at pre-revision, post-revision and at last follow-up were 23.2 ± 9.3 mm, 14.8 ± 4.8 mm and 14.9 ± 5.4 mm, respectively. Significant improvements (P = 0.004) were observed after revision surgery and there was no evident loss of correction (P = 0.703). There was no significant difference in TK, LL and SVA before and after revision surgery (all P > 0.05). At the last follow-up, no significant correction loss of above coronal and sagittal parameters were observed (all P > 0.05). The revision methods were individualized according to the primary surgical procedures and the reasons for revision. The recommended revision strategies include incision of pseudarthrosis with sufficient bone graft, fixation of satellite rods, thorough residual HV excision, prolonged fusion to S₂ and transforaminal lumbar interbody fusion at lumbosacral region. Solid bony fusion and no implant-related complication were detected during the follow-up.

CONCLUSIONS

The causes of revision surgery for patients with congenital scoliosis (CS) due to lumbosacral HV were verified and implant failure with pseudarthrosis was the main reason for failed primary operation.

The Upper Instrumented Vertebra Horizontalization: An Essential Factor Predicting the Spontaneous Correction of Compensatory Curve After Lumbosacral Hemivertebra Resection and Short Fusion

STUDY DESIGN

A retrospective study.

OBJECTIVE

To determine the significance of postoperative upper instrumented vertebra (UIV) horizontalization on the evolution of proximal compensatory curve after hemivertebra resection and short fusion in young patients with lumbosacral hemivertebra (LSHV).

SUMMARY OF BACKGROUND DATA

Postoperative compensatory curve progression (CCP) is an undesired complication in patients undergoing spinal fusion. Posterior-only hemivertebra resection and short fusion has gradually become a preferred treatment for young patients with LSHV. Postoperative UIV horizontalization might play an important role in the behavior of compensatory curve after surgery.

METHODS

This study reviewed a consecutive series of patients undergoing posterior-only LSHV resection and short fusion from August 2006 to June 2016. The radiographic parameters were measured at preoperation, immediately postoperation, and the last follow-up. Based on the immediately postoperative UIV tilt, patients were divided into horizontal group (UIV tilt < 5°) and inclined group (UIV tilt ≥5°). Postoperative CCP was defined as the Cobb angle of compensatory curve increased more than 10° than the immediately postoperative value.

RESULTS

Forty-eight patients (8.1 ± 3.4 yrs) were recruited. Seventeen patients with immediately postoperative UIV tilt more than or equal to 5° constituted the inclined group, while the other 31 patients were in horizontal group. The two groups had similar age, fusion levels, preoperative spinal curvatures, and sagittal profiles. Compared with horizontal group, patients in inclined group had greater CBD (20.7 ± 14.8 mm vs. 13.2 ± 9.9 mm, P = 0.041) and greater Cobb angle of compensatory curve (17.7 ± 8.2° vs. 9.1 ± 5.3°, P < 0.001) at the last follow-up. Thirteen patients of inclined group experienced postoperative CCP, which was more prevalent than that in horizontal group (76.5% vs. 9.7%, P < 0.001).

CONCLUSION

Horizontalizing the UIV can reduce the risk of postoperative CCP in LSHV patients undergoing posterior-only hemivertebra resection and short fusion.

LEVEL OF EVIDENCE

3.

The radiological outcomes of one-stage posterior-only hemivertebra resection and short segmental fusion for lumbosacral hemivertebra: a minimum of 5 years of follow-up

Background

Previous studies have reported favorable short-term outcomes after posterior-only hemivertebra resection and short fusion in patients with LSHV. However, there is a paucity of data evaluating the long-term outcomes following this procedure. The aim of the study is to evaluate the radiological outcomes following posterior-only hemivertebra resection and short fusion for the treatment of congenital scoliosis (CS) secondary to lumbosacral hemivertebra (LSHV) with a minimum of a 5-year follow-up.

Methods

A total of 23 patients treated with one-stage posterior-only LSHV resection and short fusion with a minimum of a 5-year follow-up were reviewed. Radiographic parameters including the Cobb angles of the lumbosacral curve and compensatory curve, the upper instrumented vertebra (UIV) tilt, and trunk shift were measured. The complications were recorded accordingly.

Results

The mean duration of follow-up was 88.6 ± 28.5 months, and the average age at surgery was 7.8 ± 3.5 years. Fusion levels averaged 3.0 ± 0.7 segments. The lumbosacral curve was corrected from 30.7 ± 10.4° to 6.7 ± 7.1° after surgery (P < 0.001), 7.3 ± 6.1° 2 years after surgery, and 8.1 ± 7.0° at the last follow-up. The compensatory curve was spontaneously corrected from 23.7 ± 9.4° before surgery to 8.3 ± 5.2° after surgery (P < 0.001). However, the angle slightly increased to 9.0 ± 4.8° 2 years after surgery and to 9.6 ± 6.4° at the last follow-up. Trunk shift was improved from 27.3 ± 8.6 mm before surgery to 11.7 ± 9.4 mm after surgery, and it decreased to 10.8 ± 8.2 mm 2 years after surgery and 10.4 ± 8.8 mm at the last follow-up. One patient experienced transient neurologic deficits after surgery. One patient was observed to have screw loosening at 1-year follow-up and received revision surgery.

Conclusion

One-stage posterior-only hemivertebra resection with short fusion is an effective procedure for LSHV, and the correction can be well maintained during longitudinal follow-up. Great attention should be paid to the restoration of lumbosacral horizontalization.

Midterm Results of Hemivertebrae Resection and Transpedicular Short Fusion in Patients Younger Than 5 Years: How Do Thoracolumbar and Lumbosacral Curves Compare?

STUDY DESIGN

Retrospective case series with comparative analysis.

OBJECTIVE

To analyze a consecutive cohort of very young patients operated for congenital scoliosis secondary to a single hemivertebra (HV) and compare thoracolumbar (TL) versus lumbosacral (LS) curve results.

SUMMARY OF BACKGROUND DATA

Despite the published successful results regarding early hemivertebra resection and short fusion for congenital hemivertebrae, literature lacks midterm results, especially in very young children.

METHODS

Patients under 5 years of age, operated by HV resection and transpedicular short fusion, with follow-up longer than 5 years, were included. Preoperative, postoperative (1-year), final radiographic parameters, and complications were recorded. Midterm results were analyzed and TL versus LS curves were compared.

RESULTS

Twenty-three patients were included (14 TL and 9 LS HV). The mean age was 3.5 ± 1.7 years and the mean follow-up was 7.6 years (4.7-13.7). The mean preoperative Cobb angle (40.3° ± 6.7°), corrected 65% postoperatively and 50% at final follow-up. The compensatory cranial curve improved spontaneously from 25.3° ± 14.8° to 13.5° ± 12° and finally to 19.9° ± 10.7°. Preoperative coronal balance corrected postoperatively but worsened at the final follow-up. TL curves corrected more initially than LS curves (TL: -29°, 68%, vs. LS: -22°, 59%; p = .043); however, both groups lost correction at the final follow-up (TL: 4°, 56%, vs. LS: 7°, 39%; p = .186). The LS group had a larger preoperative compensatory curve, which corrected with surgery but lost more correction at the final follow-up (p = .046). Segmental kyphosis was especially corrected in the TL group (TL: -14° vs. LS: -2°, p = .018) and was maintained over time.

CONCLUSION

Early hemivertebra resection and transpedicular short fusion allowed good coronal correction initially, which was difficult to maintain at midterm, especially at the LS junction. Sagittal plane correction was excellent in TL deformities and was maintained over time. Results were more challenging in the LS group compared with TL deformities. Guidance to avoid unwanted results is proposed.

LEVEL OF EVIDENCE

Level III.

One-stage posterior excision of lumbosacral hemivertebrae: Retrospective study of case series and literature review

Lumbosacral hemivertebrae causes unique problems as early trunk decompensation and long compensatory curve above. There are only a few reports on it. This case series is a fair supplement in the literatures.To evaluate the clinical and radiological outcomes of lumbosacral hemivertebrae resection through 1-stage posterior approach.Between 2005 and 2014, a consecutive series of congenital scoliosis due to lumbosacral hemivertebrae underwent hemivertebrae excision through 1-stage posterior only approach. Demographic, operative, radiological, and quality of life data were reviewed.The mean lumbosacral curve was 29 ± 7° preoperatively, 10 ± 3° postoperatively, and 13 ± 5° at the final follow up. The final correction rate was 55 ± 9%. The gravity trunk shift was 11 ± 3 mm preoperatively, 37 ± 12 mm (range, 6-49 mm) postoperatively, 14 ± 9 mm at final follow up. The rib cage shift was 36 ± 12 mm preoperatively, 19 ± 5 mm postoperatively, and 15 ± 4 mm at the final follow up. The mean blood loss was 527 ± 125 mL and the mean surgery time was 336 ± 98 minutes. The mean follow up period was 41 ± 6 months. Two patients underwent transient neurological complications, 2 had wound bad healing, and 1 got wound infection. No pseudoarthrosis and instrumentation failure was observed.One-stage posterior hemivertebrae excision could gain reasonable outcome. It is crucial to completely resect the hemivertebrae and the Y-shaped disc. Bending the rod to appropriate lordosis is helpful to close the convex side. Early surgical intervene is a preferred choice to restore the trunk balance and avoid extensive fusion. The neurological complication rate is high. Convex radiculopathy is often caused by retraction, it could recover at follow up.

L5 hemivertebra resection and T12-S1 fusion in a 14-year-old female with a 36-year follow-up

STUDY DESIGN

Case report.

OBJECTIVE

To demonstrate a 36-year follow-up of a rare operation.

SUMMARY OF BACKGROUND DATA

There have been no reports of follow-up of pediatric hemivertebra excision and fusion into midadult life.

METHODS

A chart and radiological review at 36 years after surgery.

RESULTS

The patient is alive and well and leading a normal life. Her Oswestry Disability Index is 0. Mild degenerative radiological signs are evident at the adjacent level above (T10-T12) and below (sacroiliac joints).

CONCLUSION

Early excision of the L5 hemivertebra would have been preferable, but the long-term results are good.

Thoracolumbar hemivertebrae resection by double approach in a single procedure: long-term follow-up

STUDY DESIGN

Retrospective review of patients records with clinical and radiographic assessment.

OBJECTIVE

To evaluate the long-term result of thoracolumbar hemivertebrae resection using a double approach in a single procedure.

SUMMARY OF BACKGROUND DATA

Thoracolumbar hemivertebrae resection by a combined posterior and anterior approach has been previously described, but this is the largest series of hemivertebrae reported.

METHODS

From 1987 to 2003, a consecutive series of 34 congenital scoliosis or kyphoscoliosis due to thoracolumbar hemivertebrae were managed by hemivertebra resection using a combined posterior and anterior approach and short anterior and posterior convex fusion in the same day/same anesthesia.

RESULTS

The mean age at surgery was 3.5 years. The mean follow-up period was 6.0 years. There was a mean improvement of 69.3% in the segmental curve from a mean angle of 34.8 degrees before surgery to 10.7 degrees at the latest follow-up assessment. The global scoliosis curve improved of 33.4% from 40.4 degrees to 26.9 degrees, respectively. Trunk shift was significantly improved. The mean final kyphosis was within normal values.

CONCLUSIONS

This procedure is safe and offers a persistent correction with a short segment fusion. Surgery should be performed as early as possible to avert severe local deformities and prevent secondary structural deformities in order to avoid extensive fusions.

Lumbosacral hemivertebrae resection by combined approach: medium- and long-term follow-up

STUDY DESIGN

Retrospective review of patients records with clinical and radiographic assessment.

OBJECTIVES

To evaluate the long-term result of lumbosacral hemivertebrae resection using a combined approach.

SUMMARY OF BACKGROUND DATA

Lumbosacral hemivertebrae resection by a combined posterior and anterior approach have been previously described, but only one study is concerning such a large series of hemivertebrae.

METHODS

From 1980 to 2001, a consecutive series of 17 congenital scolioses due to lumbosacral hemivertebrae were managed by hemivertebrae resection using a combined approach and short anterior and posterior convex fusion.

RESULTS

The mean age at surgery was 4.9 years. The mean follow-up period was 7.6 years. One postoperative complication was encountered: a patient had motor deficit and recovery was incomplete. The mean segmental scoliosis curve was 27.5 degrees before surgery, 10.7 degrees after surgery, and 8.9 degrees at the latest follow-up assessment. This represents a mean improvement of 61.1% after surgery and of 67.6% at the latest follow-up. The total main scoliosis curve improved from 28.4 degrees to 12.7 degrees and 11.4 degrees , respectively. It represents a mean improvement of 55.3% and 59.9%, respectively. The mean final lordosis was within normal values.

CONCLUSIONS

This procedure offers a persistent correction with a short-segment fusion. The early surgery is able to avert severe local deformities and prevent secondary structural deformities in order to avoid extensive fusions.

Lumbar hemivertebra resection

BACKGROUND

A single lumbar hemivertebra can be expected to cause progressive scoliosis. The aim of this study was to evaluate the results of a lumbar hemivertebra resection and short-segment fusion through a combined posterior and anterior approach.

METHODS

From 1987 to 2002, a consecutive series of twenty-one patients with congenital scoliosis or kyphoscoliosis due to a lumbar hemivertebra were managed by resection of the hemivertebra through a combined posterior and anterior approach and with the use of a short anterior and posterior convex-side fusion.

RESULTS

The mean age at the time of surgery was 3.3 years (range, twelve months to 10.2 years). The mean followup period was 8.6 years. There was a mean improvement of 71.4% in the segmental scoliosis curve from a mean angle of 32.9 degrees before surgery to 9.4 degrees at the time of the latest follow-up assessment, and a mean improvement of 63.9% in the global scoliosis curve from 34.1 degrees to 12.3 degrees. The mean final lordosis was within normal values.

CONCLUSIONS

Excision of a lumbar hemivertebra is safe and provides stable correction when combined with a short-segment fusion. Surgery should be performed as early as possible to avert the development of severe local deformities and prevent secondary structural deformities that would require a more extensive fusion later.

Posterior vertebral column resection in fixed lumbosacral deformity

STUDY DESIGN

Retrospective study.

OBJECTIVES

To report the results and the technique of posterior vertebral column resection (PVCR) in fixed lumbosacral deformity.

SUMMARY OF BACKGROUND DATA

Fixed lumbosacral deformity has gross imbalance as well as progressive compensatory thoracolumbar deformity because of the absence of a mobile spine caudally. There is no consensus of the surgical treatment of fixed lumbosacral deformity. Fixed lumbosacral deformity can be managed by PVCR, which not only corrects the deformity but also restores the trunk balance by translation of spinal column.

METHODS

Twenty-five consecutive fixed lumbosacral deformity patients subjected to PVCR were reviewed after a minimum follow-up of 2 years. The apical vertebra and the ultimately resected vertebra were below L4 in most cases. Etiologic diagnoses were congenital scoliosis in 6, congenital kyphoscoliosis in 3, post-traumatic kyphosis in 2, and postinfectious kyphosis in 14. The average age at the operation was 38 years (range, 2.5-61 years) with a male:female ratio of 7:18. The indication for PVCR was fixed lumbosacral deformities that could not be brought to a reasonable balance on traction or forced side bending. Before surgery, 12 patients (48%) presented with neurologic compromise and 20 patients (80%) presented with intractable back pain. The surgical technique consisted of segmental pedicle screw fixation, decompression of neural structures, and resection of the vertebral column at the apex of the deformity via the posterior route, followed by deformity correction and global fusion. During the resection, all the nerve roots were preserved.

RESULTS

Two and one tenth (2.1) vertebrae removed on average (range, 1-5 vertebrae), and 52 in all. The average fusion extent was 4.5 vertebrae (range, 2-8 vertebrae). The anterior column reconstruction was carried out with autogenous bone graft in all patients and additional insertion of titanium mesh in 12. The distal anchor went down to L5 in 4 patients, S1 in 12, and S2 in 9. Preoperative scoliosis of 38 degrees +/- 12 degrees was corrected to 15 degrees +/- 8 degrees (60% correction) at most recent follow-up, and preoperative kyphosis of 35 degrees +/- 25 degrees was corrected to -5 degrees +/- 11 degrees (40 degrees correction). The compensatory coronal curve of 26 degrees was spontaneously corrected to 12 degrees at most recent follow-up. The preoperative thoracic lordosis of -16 degrees was corrected to 4 degrees at most recent follow-up, and the preoperative lumbar kyphosis of 20 degrees was corrected to -17 degrees . Preoperative coronal imbalance of 2.0 cm was improved to 0.9 cm at most recent follow-up, and preoperative sagittal imbalance of 9.3 cm was improved to 4.6 cm. Mean operation time was 280 minutes with a blood loss of 2,810 mL. The preoperative neurologic compromise was improved in all patients, and pain was reduced to less than half of preoperative visual analog analog scale in 17 patients. The following complications were encountered in 5 patients: 2 with transient neurology that spontaneously improved without a sequel within 6 months, 2 with compression fractures at proximal adjacent vertebra, and 1 with pseudarthrosis.

CONCLUSIONS

PVCR is an effective procedure for the management of fixed lumbosacral deformity. It provides satisfactory correction and improved functional outcomes. However, it is a technically demanding and exhausting procedure with possible risks for complications.

Résultats à maturité osseuse après résection d’hémivertèbres par double abord

PURPOSE OF THE STUDY

The natural history of congenital scoliosis or kypho-scoliosis resulting from a hemivertebra is well documented. The spinal deformation generally worsens in children with a free or semi-segmented hemivertebra situated in the thoraco-lumbar, lumbar or lumbosacral region.

MATERIAL AND METHODS

From 1982 to 1997, fifteen pediatric patients with 15 hemivertebrae causing progressive scoliosis or kypho-scolisosis underwent hemivertebral resection via a double posterior and anterior approach associated with convex fusion. Mean age at surgery was 4.4 years. The fifteen patients were reviewed at bone maturity (Risser 4 or 5) to assess outcome.

RESULTS

Genitourinary tract anomalies were associated in five of the 15 patients and intrathecal anomalies in two. Mean follow-up was 12.1 years. Segmental scoliosis was 30.2 degrees preoperatively, 12.3 degrees postoperatively and 8.9 degrees at last follow-up. The values for total scoliosis were 30.5 degrees, 12.3 degrees and 12.6 degrees respectively. This was a 70.5% improvement at last follow-up for segmental scoliosis and 58.7% for total scoliosis. The real trunk imbalance improved from 31% preoperatively to 9% at last follow-up. All these differences were significant.

DISCUSSION

The main objective of surgical treatment for congenital scoliosis due to hemivertebra is to prevent the development of severe deformation which would necessitate a dangerous and difficult procedure to achieve correction. Resection of the hemivertebra via a double approach is the ideal method for early correction. The procedure not only corrects the spinal deformation but also prevents later deterioration. Correction should be performed as early as possible. The result is sustained over time if there is no other associated spinal anomaly. The procedure is safe and the technique well controlled in experimented hands. Patients need to wear a corset for only six months after resection of the hemivertebra.

New technique in congenital scoliosis involving fixation to the pelvis after hemivertebra excision

STUDY DESIGN

The authors conducted a retrospective study involving description of a new surgical technique.

OBJECTIVES

The objective of this study was to describe and evaluate the efficacy of a new technique to stabilize the spine of young and small patients with congenital scoliosis after lumbosacral hemivertebra excision.

SUMMARY OF BACKGROUND DATA

Congenital scoliosis develops as the result of anomalous vertebral development and asymmetric growth. The vertebral anomalies include congenital fusions and congenital hemivertebrae. With lumbosacral hemivertebrae at the lumbosacral junction, surgical excision followed by instrumentation to close the resulting space is frequently the best way to correct the deformity and obtain spinal balance. Surgical stabilization is required for preventing recurrent deformity and restoration of spinal balance.

METHODS

A new surgical technique for spinal correction and stabilization in congenital scoliosis is described. The technique involves hemivertebra excision followed by fixation of the adjacent normal vertebra to the ilium with screws and cables. This technique allows efficient correction in both the coronal and sagittal planes.

RESULTS

This construct was prospectively studied in 3 cases over a 3- to 5(1/2)-year period. All cases had solid fusion and well-balanced spine at latest follow up.

CONCLUSIONS

This prospective study demonstrates a successful surgical technique for spinal stabilization after congenital hemivertebra excision in infants and young children with relatively small and soft bones when standard constructs like pedicle screws may not be optimal devices. Coronal and sagittal balance (restoration with improvement of lordosis) was successfully achieved in all cases.

Postoperative shoulder-spine spica cast for young children

Immobilization of the young child after spinal surgery is an important component of the surgical plan. This study reviews the authors' experience with postoperative immobilization in a shoulder-body spica cast and provides a detailed description of the technique. Twenty-two children with an average age of 31 months at the time of surgery were placed in the shoulder-spine spica cast after hemivertebra excision. There was no loss of correction in any of the 22 children during the period of postoperative immobilization. All patients were able to be ambulatory in the shoulder-spine spica cast while immobilized. Patients experienced the minor complications of prolonged cast wear, with one cast becoming loose and three casts causing skin rash. One patient required removal of the cast 6 weeks after surgery for unrelated nausea and vomiting. The shoulder-spine spica cast has been used at the authors' institution with great success and allows children to be ambulatory after hemivertebra resection.

Thoracic hemivertebra excision in adults via a posterior-only approach

Hemivertebrae are a common cause of congenital scoliosis. Depending on their location and the magnitude of the resultant deformity, they may be asymptomatic or require treatment. In the past, treatment has focused on prevention of deformity progression in growing children. Little has been written about congenital scoliosis presenting in adulthood. Because the aging of the spine is a kyphosing process and hemivertebrae often present with a local segmental kyphotic alignment, this can become symptomatic. Excision of hemivertebrae is well established as a safe and effective procedure when treatment is required. Initially this was conducted via a combined anterior–posterior approach. Recently some authors have indicated that in the lumbar spine hemivertebra resection can safely and effectively be achieved via a single posterior transpedicular approach. The authors report two adult cases in which they performed posterior transpedicular lateral extracavitary excision of a thoracic, fully segmented hemivertebrae. Essentially complete correction of the deformity was achieved. There were no neurological complications. The patients were spared a thoracotomy and no chest tubes were required.

Ten-year follow-up study of lower thoracic hemivertebrae treated by convex fusion and concave distraction

STUDY DESIGN

A retrospective review of patient records with recent clinical and radiologic assessment was conducted.

OBJECTIVE

To evaluate the long-term results of fully segmented hemivertebrae treated by convex fusion combined with instrumented concave subcutaneous distraction.

SUMMARY OF BACKGROUND DATA

Convex fusion has been described for the treatment of hemivertebrae in children, whereas distraction without fusion has been shown to enhance spinal growth. No long-term follow-up studies have combined these two methods.

METHODS

Between 1986 and 1994, six consecutive patients (5 males and 1 female) with hemivertebrae located at T11 or T12 underwent convex anterior and posterior fusion as well as concave subcutaneous distraction without fusion.

RESULTS

The mean age at surgery was 3.4 years. The mean follow-up period was 10.8 years (range, 8-14 years). There was a mean improvement of 41% in the coronal deformity, from a mean angle of 49 degrees before surgery to 29 degrees at the latest follow-up assessment. In four of the cases, this correction was achieved immediately after surgery and did not significantly change despite repeated distraction. The kyphosis improved in three cases, remained unchanged in one case, and deteriorated in two cases. In these two cases, an adjacent wedge vertebra contributed to the kyphotic deformity.

CONCLUSIONS

Although growth-mediated correction was seen in only two cases, this procedure could be recommended for children with severe deformities and decompensation in the lower thoracic spine. It is safer than hemivertebra excision, with less risk of spinal cord injury. The concave distraction produces immediate improvement in the coronal balance, such that there is no need to wait for uncertain growth-mediated correction in patients who undergo convex fusion only.

Single-stage excision of hemivertebrae via the posterior approach alone for congenital spine deformity: follow-up period longer than ten years

STUDY DESIGN

Evaluation of the long-term results for single fully segmented hemivertebrae were subjected to single-stage excision via posterior approach alone.

OBJECTIVES

To describe the long-term results of this procedure.

SUMMARY OF BACKGROUND DATA

In the case of congenital spinal deformity caused by a single, full hemivertebra, excision of the hemivertebra is ideal for obtaining a good correction percentage even in short segments. Recently, single-stage excision of a hemivertebra using a combined anterior and posterior approach has been reported.

METHODS

Five patients with a hemivertebra underwent surgery. The hemivertebra involved the thoracolumbar region in three cases and the lumbosacral region in two cases. After removal of a lamina of the hemivertebra, the body of the hemivertebra was visualized easily because the spinal cord had deviated to the concave side of the curve. The vertebral body, along with its cranial and caudal discs, was curetted with this approach. Thereafter, bone chips were grafted into the defect created by vertebrectomy. The results of this surgical procedure, especially those observed during long-term follow-up evaluation, were investigated.

RESULTS

For patients with a thoracolumbar hemivertebra, scoliosis improved from 49 degrees +/- 6 degrees to 22.3 degrees +/- 3.5 degrees, for a 54.3% correction. The correction ratio for kyphosis was 67.4%. Over an average 12.8-year follow up period, loss of scoliotic curvature correction was only 3.7 degrees. In contrast, the hemivertebral correction ratio for patients with a lumbosacral hemivertebra remained 32.5% because of difficulty using internal fixation associated with patient age. At the most recent follow-up assessment, one patient exhibited deterioration of coronal spinal balance.

CONCLUSION

The described procedure was less invasive because it avoided an anterior approach, yet it yielded satisfactory long-term results for thoracolumbar hemivertebrae.