J Korean Soc Spine Surg.  2003 Mar;10(1):55-63. 10.4184/jkss.2003.10.1.55.

Prevention of the Crankshaft Phenomenon with Posterior Pedicle Screw Fixation in Scoliosis of the Skeletally-Immature Spine

• Suk SI
• Chung ER
• Kim JH
• Lee SM
• Lee JH
• Lee JH
• Kim SS
• Park JS

• KMID: 2209705
• DOI: http://doi.org/10.4184/jkss.2003.10.1.55

Abstract

STUDY DESIGN: A retrospective study.
OBJECTIVES
To evaluate the results of posterior segmental pedicle screw fixation in skeletally immature patients with scoliosis. SUMMARY OF LITERATURE REVIEW: Scoliosis correction, in the immature spine, frequently necessitates additional anterior surgery to prevent the crankshaft phenomenon. With the advent of posterior segmental pedicle screw fixation, it is unclear whether an additional anterior procedure will be required. MATERIAL AND METHODS: Seventeen scoliosis patients (10 idiopathic, 4 congenital and 3 others; 3 males and 14 females) were treated with segmental pedicle screw fixation only. Their results were reviewed for a deformity progression of more than 10 degrees, a rib vertebra angle difference (RVAD) progression of more than 10 degrees, and evidence of adding-on. All the patients had a 0 Risser index at the time of the operation. The mean age and follow-up times were 10.4, ranging from 7.2 to 11.8 years old, and 4.0, ranging from 3.0 to 5.4 years, respectively.
RESULTS
The mean preoperative thoracic curve of 55 degrees was corrected to 22 degrees (58% correction) at last follow-up and the nonstructural lumbar curve of 31 degrees was corrected to 10 degrees (67% correction) at last follow-up. Preoperative thoracic kyphosis of 28 degrees was improved to 34 degrees at last follow-up. The RVAD were 23 degrees and 13 degrees, preoperatively and postoperatively, respectively. No patient showed a progression of 10 degrees or more in the postoperative coronal curve or RVAD. One patient had a progression of the deformity caudal to the instrumented segments. There were no neurological or screw-related complications.
CONCLUSIONS
Posterior segmental pedicle screw fixation in skeletally immature patients with scoliosis may be effective in preventing the crankshaft phenomenon.

Keyword

Idiopathic scoliosis; Crankshaft phenomenon; Segmental Pedicle screw fixation; Immature spine

MeSH Terms

Congenital Abnormalities
Follow-Up Studies
Humans
Kyphosis
Male
Retrospective Studies
Ribs
Scoliosis*
Spine*

Figure

• 

  Fig. 1. Case 9. 10.5-year-old girl with juvenile idiopathic scoliosis. She was during her peak height velocity at operation, and had closed triradiate cartilage. Fig. 1 A, B. Preoperative anteroposterior and lateral radiographs showed 88° of main thoracic and 50° of proximal thoracic curve. Preoperative RVAD was 31°. Fig. 1.C, D. Anteroposterior and lateral radiographs taken 1 month after operation. Main thoracic curve and proximal thoracic curve were corrected to 27° and 23°, respectively. RVAD was 27°. Fig. 1.E. F. Anteroposterior and lateral radiographs taken 4 year after operation. Main thoracic curve and proximal thoracic curve were 28° and 25°, respectively. RVAD was 24°. In serial radiographs, there was neither curve nor RVAD progression more than 10°.

Reference

1). Burton DC., Asher MA., Lai SM. Scoliosis correction maintenance in skeletally immature patients with idiopath -ic scoliosis. Is anterior fusion really necessary? Spine,. 25:61–8. 2000.

2). Burwell RG. The relationship between scoliosis and growth. Zorab PA,, editor. Scoliosis and Growth,. Edin -burgh, London: Churchill Livingstone;p. 131–50. 1971.

3). Calvo IJ. Observations on the growth of the female ado -lescent spine and its relation to scoliosis. Clin Orthop,. 10:40–47. 1957.

4). Dohin B., Dobousset JF. Prevention of the crankshaft phenomenon with anterior spinal epiphysiodesis in surgi -cal treatment of severe scoliosis of the younger patient. Eur Spine J,. 3:165–8. 1994.

5). Dubousset J. Recidive d'une scoliose lombaie et d'un bassin oblique apres fusion prococe; Le phenomene due Villebrequin. Proceedings Group etud de la Scoliose. Lyon, France: CRF Massues;p. 62–7. 1973.

6). Dubousset J., Herring JA., Shufflebarger H. Th e crankshaft phenomenon. J Pediatr Orthop,. 9:541–50. 1989.

7). Duval-Beaupere G. Pathogenic relationship between sco -liosis and growth. Zorab PA,, editor. Scoliosis and Growth,. Edinburgh, London: Churchill Livingstone;p. 58–64. 1971.

8). Hamill CL., Bridwell KH., Lenke LG., Chapman MP., Bal-dus C., Blanke K. Posterior arthrodesis in the skeletal -ly immature patient. Assessing the risk for crankshaft: is an open triradiate cartilage the answer? Spine,. 22:1343–51. 1997.

9). Hefti FL., McMaster MJ. The effect of the adolescent growth spurt on early posterior spinal fusion of the spine in infantile and juvenile idiopathic scoliosis. J Bone Joint Surg [Br],. 65:247–54. 1983.

10). Kim WJ., Rivard CH., Colliard C., Rhalmi S. Th e effect of segmental pedicle screw instrumentation on actively growing spine- a longterm experimental study. Presented at the 36th annual meeting of the Scoliosis Research Society, Cleveland, Ohio,. 2001.

11). Kioschos HC., Asher MA., Lark RG., Harner EJ. Overpowering the crankshaft mechanism. The effect of posterior spinal fusion with and without stiff transpedicu lar fixation on anterior spinal column growth in immature canines. Spine,. 21:1168–73. 1996.

12). Lapinksy AS., Richards BS. Preventing the crank -shaft phenomenon by combining anterior fusion with pos -terior instrumentation.: Does it work? Spine. 20:1392–8. 1995.

13). Lee CS., Nachemson AL. The crankshaft phenome -non after posterior Harrington fusion in skeletally immature patients with thoracic or thoracolumbar idiopathic scoliosis followed to maturity. Spine. 22:58–67. 1997.

14). Metha MH. The rib-vertebra angle in the early diagnosis between resolving and pregressive infantile scoliosis. J Bone Joint Surg [Br],. 54:230–43. 1972.

15). Mullaji AB., Upadhyay SS., Luk KD., Leong JC. Vertebral growth after posterior spinal fusion for idio -pathic scoliosis in skeletally immature adolescents. The effect of growth on spinal deformity. J Bone Joint Surg [Br],. 76:870–6. 1994.

16). Risser JC. Important practical facts in the treatment of scoliosis. AAOS Instr Course Lectures. 5:248–60. 1948.

17). Risser JC., Ferguson AB. Scoliosis: Its prognosis. J Bone Joint Surg,. 3:667–70. 1936.

18). Roberto RF., Lonstein JE., Winter RB., Denis F. Curve progression in Risser stage 0 or 1 patients after posterior spinal fusion for idiopathic scoliosis. J Pediatr Orthop,. 17:718–25. 1997.

19). Sanders JO., Herring JA., Browne RH. Poste rior arthrodesis and instrumentation in the immature(Risser grade-0) spine in idiopathic scoliosis. J Bone Joint Surg [Am],. 77:39–45. 1995.

20). Sanders JO., Little DG., Richards BS. Prediction of the crankshaft phenomenon by peak height velocity. Spine. 22:1352–7. 1997.

21). Shufflebarger HL., Clark CE. Prevention of the crankshaft phenomenon. Spine. 16(Suppl):S409–11. 1991.

22). Suk SI., Kim WJ., Kim JH., Lee SM. Pedicle screw fixation in pediatric spinal deformities: Results in patients under 10 years old. Presented at the 35th annual meeting of the Scoliosis Research Society, Cairns, Australia,. 2000.

23). Suk SI., Kim WJ., Lee SM., Kim JH., Chung ER. Thoracic pedicle screw fixation in spinal deformity: Are they really safe? Spine. 26:2049–57. 2001.