Complex Spine Cases: A Collection of Current Techniques Munish C Gupta, Alexander Richard Vaccaro, Sachin Gupta
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1Early Onset Scoliosis (EOS)
Chapters
  • ○ Congenital Scoliosis Treated with Growing Rods and VEPTR
  • ○ Treatment of Lumbar Congenital Scoliosis with Bilateral Vertical Expandable Prosthetic Titanium Rib (VEPTR) in a Child with Central Core Disease
  • ○ Iatrogenically Fused Ribs and Progressive Early Onset Scoliosis following Repair of Congenital Diaphragmatic Hernia
  • ○ Early Onset Scoliosis: Treatment with Dual Growing Rods
  • ○ Severe Scoliosis in Three Young Children Treated with Shilla
  • ○ Progressive Congenital Kyphoscoliosis Treated with Vertebrectomy and a Posterior Growth Guidance Construct2

Congenital Scoliosis Treated with Growing Rods and VEPTRCHAPTER 1

Lindsay Andras,
DavidSkaggs
 
INTRODUCTION
The management of early onset scoliosis (EOS) is complicated by a need to control the progression of spinal deformity without negatively impacting pulmonary function with early fusion.13 In order to allow growth, and subsequently increase the space available for lung development, “growth friendly” instrumentation has been developed to help correct and stabilize spinal deformity. This type of instrumentation has many technical obstacles and a high complication rate.4
Congenital scoliosis is associated with stiff curves that can progress relentlessly and that are not responsive to bracing.5 It is particularly challenging to treat cases where there is involvement of the upper thoracic or cervical spine.
In this region, the scoliosis often causes significant deformity in the form of a head tilt. There is no room for a compensatory curve above the deformity as usually occurs in congenital scoliosis involving the lower thoracic or lumbar spine. One goal in these cases is to improve head position by decreasing T1 tilt, while trying to maximize thoracic volume at the same time.
We report on two cases of congenital scoliosis that were managed with distraction-based implants. We describe how in both cases complications occurred and were managed with successful ultimate outcomes.
 
CASE REPORTS
 
Case 1
The patient presented to our clinic at the age of 21 months with severe, rigid torticollis. Her right ear was resting on her shoulder. Examination revealed a high left thoracic prominence and no neurologic deficits.
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Fig. 1: Radiographs show a unilateral bar from T1 to T5 resulting in 55° cervicothoracic scoliosis.
(Used with permission from Children's Orthopaedic Center, Los Angles)
Radiographs revealed multiple vertebral anomalies with a unilateral bar on the right from T1 to T5 resulting in a 55° cervicothoracic scoliosis. In addition, there were congenitally fused ribs, a T1 tilt of 30° and a hypoplastic right lung (Fig. 1). T1 to S1 distance measured 22.5 cm. Magnetic resonance imaging (MRI) was negative for any intraspinal pathology.
At age 2, she underwent placement of a vertical expandable prosthetic titanium rib (VEPTR) construct with thoracotomy (Fig. 2). One VEPTR was placed from rib to rib and a second was placed from the ribs to L2. She did well following this and had significant correction of her deformity and head alignment.
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Fig. 2: Postoperative radiograph showing placement of rib to rib and rib to spine vertical expandable prosthetic titanium ribs (VEPTRs).
(Used with permission from Children's Orthopaedic Center, Los Angles)
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Fig. 3: Radiograph obtained after bone grafting and removal of distractive forces (medial upper hook and lateral connector) to allow healing of dissociated ribs and spine.
(Used with permission from Children's Orthopaedic Center, Los Angles)
Five months from the time of implantation, she was noted to have an acute prominence of the superior implant. Radiographs confirmed that the hooks had migrated. When she underwent revision surgery, we were able to visualize that the rib had disassociated from the spine. The dislodged hook was removed but the rib sleeve was left in place. Bone graft was harvested from the fourth rib and packed between the disassociated rib and the thoracic spine. The goal was to fuse the rib to the spine to allow for future distraction (Fig. 3).
Six months later, she returned to the operating room and at that time the fusion of the ribs to the spine appeared solid. The rib was reinstrumented with minimal distraction to avoid putting additional stress on this region. Between the ages of 3 and 9, she underwent a total of 11 more uneventful lengthening procedures, with the standard amount of distraction and exchange of the rods as needed.
At age 9, an 8 × 3 mm2 area of skin breakdown was noted over the rods superiorly. She underwent exchange of her implants followed by successful flap coverage. Her head tilt was significantly improved from her initial presentation, but was not completely neutral (Fig. 4). Various surgical treatments were discussed, including hemivertebrectomy or vertebral column resection, but the family was satisfied with her head position. Their main concern was avoiding any neurologic complications. At the age of 11, she underwent a spinal fusion from T1 to L3 with multiple ponte osteotomies. Minimal correction was achieved at that time, but no complications occurred.
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Fig. 4: Radiograph at age 11 prior to definitive fusion.
(Used with permission from Children's Orthopaedic Center, Los Angles)
Following conversion to fusion, the T1 tilt was 24° and her T1 to S1 length measured 35.3 cm (Fig. 5). Her T1 to S1 length increased 12.8 cm during treatment. While this represents a significant change in height and in the size of her thoracic cavity, it is still less than the 21.7 cm that would be predicted based on Dimeglio growth charts.6 Both the patient and her family were quite pleased with the results.
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Fig. 5: Recent radiographs, age 12, after conversion to posterior spinal fusion. T1 tilt corrected to 24°. T1 to S1 increased to 35.3.
(Used with permission from Children's Orthopaedic Center, Los Angles)
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Fig. 6: Photograph shows a large stiff thoracolumbar curve affecting head position at presentation.
(Used with permission from Children's Orthopaedic Center, Los Angles)
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Figs. 7A and B: (A) Radiographs at presentation (age 3) show a large congenital bar in the lower thoracic spine with fused ribs. Cobb angle was 106°, T1 tilt 35° and T1 to S1 distance was 16 cm. (B) Traction radiograph shows the stiff nature of this curve.
(Used with permission from Children's Orthopaedic Center, Los Angles)
 
Case 2
The patient presented at the age of 3 with severe congenital scoliosis. He had previously undergone two detethering procedures for diastematomyelia at an outside institution. He had a severe head tilt due to congenital scoliosis (Fig. 6). Radiographs revealed a large congenital bar on the concavity in his thoracic spine, with fused ribs (Fig. 7A). Cobb angle of the thoracic curve measured 106° and T1 tilt measured 35°. T1 to S1 distance measured 16 cm. The deformity was extremely rigid on both clinical exam and traction radiographs (Fig. 7B).
After discussing various treatment options, the family elected to proceed with surgery with distraction-based instrumentation. After positioning and prior to incision, it was noted that no MEPs or SSEPs could be obtained in any extremity.
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Fig. 8: Postoperative radiographs following index surgery show significant improvement, but there continued to be a large curve measuring 87° and T1 tilt of 25°.
(Used with permission from Children's Orthopaedic Center, Los Angles)
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Fig. 9: Radiograph demonstrating failure of the side-to-side connector between the rods. Sometimes this is a subtle radiographic finding. The diagnosis is confirmed by measuring the distance at the free end of the rod above the connector. In this case it measured 6 mm more than it had on prior radiographs, thus confirming the diagnosis..
(Used with permission from Children's Orthopaedic Center, Los Angles)
At this point, the surgeon had a discussion with the family about the increased risk of neurologic injury and they expressed their understanding and desire to continue. The patient underwent growing rod instrumentation on the concavity of the curve from the ribs at T2 and T3 to L3. This consisted of a single rod with standard laminar hooks at the superior aspect of the construct. The hooks were placed on the ribs in an up going configuration. The construct was distracted until a firm end point was reached. A wakeup test was performed and the patient was noted to be moving all extremities. Postoperatively, he had a normal neurologic examination and radiographs revealed that the curve was corrected to 87 and T1 tilt to 25° (Fig. 8).
Six months later the patient underwent an uneventful lengthening of the construct. Then at just over a year from the initial operation, the parents noted that the patient was suddenly shorter. Radiographs revealed that the side-to-side connector between the rods had failed (Fig. 9). He underwent replacement of the side-to-side connector and distraction, which was well tolerated. He also underwent an uneventful lengthening approximately 6 months after this revision.
At 2 years after his initial instrumentation, the superior hook was noted to have migrated through the rib (Fig. 10).
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Fig. 10: Radiograph obtained at age 6 shows the superior hook has migrated and is no longer anchored to the rib.
(Used with permission from Children's Orthopaedic Center, Los Angles)
At the time of revision, it appeared that the hook had migrated through the second rib which had subsequently healed. As is often the case following migration of hooks through the ribs, this created a solid area of hypertrophic bone that provided an excellent anchor point for a new laminar hook (Fig. 11).
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Fig. 11: Radiograph following revision of the implants with a new hook anchored to the area of hypertrophic bone created by slow migration of the previous hook.
(Used with permission from Children's Orthopaedic Center, Los Angles)
Subsequently the patient has undergone four additional lengthening procedures that were all uneventful and he is now 9 years old. He has not had any subsequent complications and is quite active. His T1 to S1 distance increased from an initial measurement of 16 to 18.5 cm after the first surgery and is now 21 cm. This difference of 5 cm is less than half of the predicted growth during this time period of 12.9 cm, but still represents improvement over definitive fusion.6
While he still has a significant curve in the thoracic region measuring 68°, T1 is in a neutral position as are his head and shoulders (Figs. 12A to C). His parents report that he runs and jumps easily and participates in activities with his peers without difficulty.
 
CASE SUMMARIES
In the first case, we present a 21-month-old female with a marked head tilt. Her ear was resting on her shoulder and she had severely limited neck range of motion. Radiographs demonstrated a 55° cervicothoracic scoliosis involving a unilateral bar from T1 to T5 with 30° of T1 tilt. At 23 months of age, she underwent placement of a VEPTR construct for distraction-based correction.
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Figs. 12A to C: (A) Current clinical radiograph showing improvement of shoulder balance and head position. (B and C) Radiographs demonstrating current alignment. Cobb angle measures 68°, T1 to S1 has increased to 21 cm, shoulders are well balanced and T1 is now in a neutral position.
(Used with permission from Children's Orthopaedic Center, Los Angles)
After her initial surgery, her rib pulled off of her spine and this was treated by removing the distractive force from the rib, and bone grafting the rib to the spine, then continuing with distraction once the rib was fused to the spine. She then underwent multiple lengthening procedures to maintain and improve her head position. Her clinical course was again complicated by superior migration of the upper anchor. At the age of 11, she was converted to a final fusion.
In the second case, a 3-year-old male with congenital scoliosis presented with a 90° thoracic curve and T1 tilt. He underwent distraction-based growing rod instrumentation with the superior anchors attached to the ribs. His clinical course was complicated by implant failure (side-to-side connector collapsing) and superior migration of the implants, but otherwise, the treatment went well. Standard spinal hooks were used as rib anchors and thoracotomy was not performed. At 10 years of age, he has both achieved and maintained a neutral head position.
 
DISCUSSION
Congenital scoliosis is often associated with stiff curves that are unresponsive to bracing making them particularly challenging to treat. This is especially true of cases in which there is involvement of the upper thoracic or cervical spine resulting in a marked head tilt. Surgical options for management of congenital cervicothoracic scoliosis have traditionally included posterior fusion in situ or resection of the hemivertebrae.710 In situ fusion 8poses less neurologic risk but does not allow for significant correction. The deformity persists resulting in an asymmetric head position. Hemivertebrae resection allows for correction of the deformity but carries increased risk of neurologic or vascular injury.10 Resection of multiple hemivertebrae increases the risk of neurologic injury and often one hemivertebrae resection cannot provide adequate correction.
Distraction-based spine implants were designed to maximize thoracic growth and lung development in young children with severe scoliosis. The first case report illustrates that this technique can be utilized to improve head tilt in cases of cervicothoracic scoliosis. Although “growth friendly” instrumentation may avoid the problems associated with early fusion, there are frequent complications. Rates range from 58% to 200% and include implant migration, rod breakage and wound complications.11,12 Both children had complications requiring surgical interventions and revision of implants. Nevertheless, distraction-based instrumentation offers a means for gradual correction of the deformity and provides an alternative to early fusion.
It can be challenging to achieve solid fixation at the upper end of the construct in cases of severe congenital scoliosis with significant T1 tilt. In the first case, we used VEPTR anchors. In the second case, we were able to use standard laminar hooks on the ribs to address the T1 tilt in a manner similar to the constructs using the VEPTR rib cradles.13,14 Using spinal hooks as rib anchors allows the use of standard spinal systems which may decrease cost, decrease inventory and avoid the need for Internal Review Board approval in some institutions. Additionally spinal hooks are within the standard expertise of operating room personnel and surgeons. We have found this to be a simpler and equally effective option.
Campbell et al. have previously described the treatment of children with congenital thoracic scoliosis and cervical tilt with VEPTR opening wedge thoracotomy.13 In their series, they describe 14 cases of patients with cervical tilt and thoracic insufficiency syndrome that improved in regard to space available for the lung, cervical tilt, and head and truncal decompensation. We have found that in cases of congenital cervicothoracic scoliosis, thoracotomy can generally be avoided.
In milder congenital deformities, our preference is to perform a single hemivertebrae excision if this will correct head tilt. However, in complex deformities with multiple congenital anomalies not amenable to a single hemivertebrae excision, we offer this technique as a safe and gradual alternative to vertebral resection (Box 1).
 
CONCLUSION
We describe two cases of congenital scoliosis encountered in the growing spine with severe deformity that were managed with distraction-based instrumentation. Both patients encountered complications but these were managed with revision surgery and successful outcomes were achieved in both cases. By avoiding early fusion, this treatment not only allowed for further growth but also more gradual correction of the deformity while avoiding the neurologic risks that may be encountered with multiple hemivertebrae excision or vertebral column resection.
REFERENCES
  1. Akbarnia BA, Marks DS, Boachie-Adjei O, et al. Dual growing rod technique for the treatment of progressive early-onset scoliosis: a multicenter study. Spine. 2005;30 (17 Suppl):S46–57.
  1. Karol LA, Johnston C, Mladenov K, et al. Pulmonary function following early thoracic fusion in non-neuromuscular scoliosis. J Bone Joint Surg Am. 2008;90(6):1272–81.
  1. Karol LA. Early definitive spinal fusion in young children: what we have learned. Clin Orthop Relat Res. 2011;469(5):1323–9.
  1. Gomez JA, Lee JK, Kim PD, et al. “Growth friendly” spine surgery: management options for the young child with scoliosis. J Am Acad Orthop Surg. 2011;19(12):722–7.
  1. Winter RB, Moe JH, MacEwen GD, et al. The Milwaukee brace in the nonoperative treatment of congenital scoliosis. Spine. 1976;1:85–96.
  1. Morrissy RT, Weinstein SL. Lovell and Winter’s Pediatric Orthopaedics, 6th edition.  Philadelphia, PA;  2005.
  1. Liew SM, Simmons ED Jr. Cervical deformity: rationale for selecting the appropriate fusion technique (anterior, posterior, and 360 degree). Orthop Clin North Am. 1998;29(4):779–86.

  1. 9 Smith MD. Congenital scoliosis of the cervical or cervicothoracic spine. Orthop Clin North Am. 1994;25(2):301–10.
  1. Winter RB, Moe JH, Lonstein JE. Posterior spinal arthrodesis for congenital scoliosis. An analysis of the cases of two hundred and ninety patients, five to nineteen years old. J Bone Joint Surg Am. 1984;66(8):1188–97.
  1. Ruf M, Jensen R, Harms J. Hemivertebra resection in the cervical spine. Spine. 2005;30(4):380–5.
  1. Bess S, Akbarnia BA, Thompson GH, et al. Complications of growing-rod treatment for early-onset scoliosis: analysis of one hundred and forty patients. J Bone Joint Surg Am. 2010;92(15):2533–43.
  1. Sankar WN, Skaggs DL, Yazici M, et al. Lengthening of dual growing rods and the law of diminishing returns. Spine. 2011;36(10):806–9.
  1. Campbell RM Jr, Adcox BM, Smith MD, et al. The effect of mid-thoracic VEPTR opening wedge thoracostomy on cervical tilt associated with congenital thoracic scoliosis in patients with thoracic insufficiency syndrome. Spine. 2007;32(20):2171–7.
  1. Emans JB, Caubet JF, Ordonez Cl, et al. The treatment of spine and chest wall deformities with fused ribs by expansion thoracoplasty and insertion of vertical expandable prosthetic titanium rib. Spine. 2005;30(suppl):58–68.