Mechanical comparative analysis of three different types of sutures in different dimensions tendons - experimental study

Tratamento cirúrgico da cifose congênita

Mechanical comparative analysis of three different types of sutures in different dimensions tendons - experimental study

Tratamento cirúrgico da cifose congênita

Raimundo Nonato R. Medeiros^I; José Wilson RodriguezII; Roberto Basile Jr.^III; Clelgen Luis Bonetti^IV; Carlos Alberto dos Santos^V; Tarcisio Eloy Pessoa Barros Filho^VI

^IHead of Service of Orthopaedics and Trauma, UFP

^IIDoctor Orthopaedics, UFP

^IIIPhD in Orthopaedics, IOT, HC, FMUSP

^IVMaster in Orthopaedics, FMUSP

^VDoctor Orthopaedics, IOT, FMUSP

^VIAssociate Professor and Diretor of Spin Service of IOT, FMUSP

^{Address for correspondence}

SUMMARY

The authors present sixteen patients with congenital kyphosis treated by posterior spinal arthrodesis. A homologous or autogenous iliac bone graft was used. The patients walked with Risser-Cotrel body cast in the 6 months of postoperatory period. The mean time of follow-up was 58,25 months and the mean age of the patients at time of surgery was 9,3 years. The mean angular value of the congenital kyphosis before surgery was 50,44º Cobb and after ther surgery it was 46,94º Cobb. One of the patients who had curve of 69º Cobb, presented pseudoarthrosis. The final results were good in 10, regular in 4 and bad in 2 patients. The need of the diagnostic and precocious treatment is recommended by authors.

RESUMO

Os autores apresentam dezesseis pacientes portadores de cifose congênita que foram tratados pela artrose vertebral posterior.Utilizaram enxerto do osso ilíaco autógeno em doze casos e homólogo em quatro casos. Deambularam com aparelho gessado de Risser-Cotrel no pós-operatório por seis meses. A média de idade, na época da cirurgia, foi de 9,3 anos com valor angular médio da cifose pré-operatória de 50,44 graus (Cobb) e pós-operatória de 46, 94 graus (Cobb), com tempo médio de seguimento de 58,25 meses Foi constatado um caso de pseudoartrose em um paciente com curva de 69 graus (Cobb). Os resultados obtidos foram: Dez bons, quatro regulares e dois maus. Os autores alertam para a necessidade do diagnóstico e tratamento precoces.

INTRODUCTION

Congenital kyphosis is defined as a deformity which is consequent to the presence of one or more anomalous vertebrae, leading to an anterior-posterior inclination of the spine. This is generally an structured curve, rigid and limited to the area of the bony defect. It can be associated to other malformations such as of ribs, kidney, cardiovascular, neurological or the extremities. Congenital kyphosis is rare even in large spinal deformities treatment centers. However its complications can be severe, being paraplegia the most important among them.

Central nervous system malformation, eventually associated to congenital abnormalities of the spine, pose an obstacle for correction of the deformities due to the risk of injuries. Congenital kyphosis is the most common, other than infective ones, deformity causing paraplegia when not accordingly treated or when corrective forces are applied.

The objective of this work was to evaluate the results of treatment of congenital kyphosis with posterior spinal arthrodesis by the analysis of sixteen cases submitted to surgery.

CASES AND METHODS

Cases

The patients presented in this report were from the Instituto de Ortopedia e Traumatologia da Faculdade de Medicina da Universidade de São Paulo (three cases) and from the Clínica de Acidentados São Lucas (Teresina - Piauí - Brazil) (13 cases).

From March 1975 to March 1991 sixteen patients underwent surgery as reported in (^{Board 1}), in chronological order of surgery. In this table, cases are reported by order number, gender and age (years and months) by the time of the surgery.

Complementary cardiologic, pulmonary and renal evaluation

Was performed by:

1 ¾ Electrocardiogram

2 ¾ Lung function tests

3 ¾ Excretory urography in three cases, and urinary system ultrasonography in 13 cases.

Electrocardiogram of patient number 12 presented synusal tachicardia and left ventricular overload. Patient number 7 presented with Wolf-Larkinsen-White syndrome. These alterations did not prevent the surgery to be performed.

Lung function tests were normal in all patients.

Patient # 10 ultrasonography presented with an ectopic right kidney.

Preoperative radiographic evaluation

Preoperative radiographic evaluation was performed by plain standing spine radiography in anterior-posterior and lateral views. In case # 13 a planigraphy was performed, since plain radiography did not allow a clear identification of the defect. Measurement of kyphosis degree was performed by Cobb's (1948)⁴ method in the radiographs in lateral view. (Fig. 1, 2 and 3). Mean angular value of kyphotic curve was 50.44^o ranging from 18^o to 77^o (Table 1).

Regarding topography, toracolumbar curves were the most frequent, as demonstrated (Table 2).

Defect evaluation

Radiographic classification of defects is based on Winter et al. (1973)^(41):

I ¾ Total or partial absence of one or more vertebral bodies.

II ¾ Lack of segmentation between vertebal bodies.

III ¾ Types I and II associated.

As displayed (Table 3), Type I was the most frequent.

METHOD

Arthrodesis

Posterior vertebral arthrodesis was the technique in all 16 patients.

Arthrodesis area involved the kyphotic curve, two vertebrae above and two below of the congenital defect.

Postoperative

It was used antibiotic prophilaxis, as standardized in our service, was used.

For 10 days patients were kept at rest, and in the first 48 hours decubitus was changed every 4 hours.

In the second postoperative day, suction drain was removed and bandage changed.

In tenth day a Risser-Cotrel cast was applied in an adapted Risser table. Patients were allowed to walk in the next day, and the cast kept for six months.

Postoperative radiographic evaluation

After removal of the cast mold on 6th month, were taken anterior-posterior and lateral radiographs in order to evaluate the spine arthrodesis and measurement of the curves.

Radiographs (anterior posterior and lateral) were repeated every four months in order to evaluate the evolution of the curves. The mean follow-up was 58.25 months.

Results evaluation criteria

Based on the principles by Winter, Moe and Lonstein (1985)³⁴, who considered as significant an increase above 10^o in the kyphosis degree during a postoperative follow-up period of 1 year or more, the results were evaluated as below:

GOOD ¾ when an improvement or non progression of the kyphotic angle was observed during the postoperative follow-up period.

REGULAR ¾ when the kyphosis angle increased up to 10^o.

POOR ¾ when an increase in kyphosis angle above 10^o or pseudarthrosis was observed.

RESULTS

A radiographic evaluation, in accordance to the criteria above presented was performed after a follow-up ranging from 25 to 149 months, average 58.25 months.

Clinical and radiographic analysis

Clinical and radiographic postoperative analysis is summarized in (^{Board 2}).

Based on the evaluation criteria the following results were observed: 10 good, 4 regular and 2 poor.

COMPLICATIONS

Complications were:

1 ¾ Immediate [ Subcutaneous haematoma, case 7 ]

2 ¾ Late [ pseudarthrosis, case 8 ]

DISCUSSION

Among spinal congenital deformities, congenital kyphosis stands out as a rare affection, however when present and not treated can lead to important deformity and sometimes paraplegia.

Our series, in general, is comparable to others in literature.

Age ranged from 2 to 14 years, averaging 9 years and 3 months. We would like to operate these patients earlier, however our cultural and social environment didn't allow it. Winter et al. (1973)³⁰ showed in their series an average age of 10.5 years that they consider to be high, while again Winter and Moe (1982)³³ operated their cases at ages below 5 years.

The higher incidence of females as observed in our series is also described in literature by several authors, such as Winter et al. (1973)³⁰, Leattermann et al. (1978)¹⁴ and Montgomery and Hall (1982)²⁰.

Regarding types of congenital defect, we found 75% as Type I, 18.75% as Type II and 6.25% as Type III. Predominance of type II is also described in the literature in almost all series on the subject (James, 1955¹³; Winter et al. 1973³⁰; Montgomery and Hall, 1982²⁰).

Location of the kyphotic curve was distributed as follows: 18.75% as thoracic, 68.75% in the lumbar-thoracic transition and 12.5% as lumbar. This higher incidence in thoracolumbar joins what is generally described in literature (Winter et al. 1973³⁰ Mayfield et al. 1980¹⁷ and Morin et al. 1985²¹). Cervical location is considered as rare and was not found in this series, while James (1959)¹³ and Shiba et al. (1993)²⁷ reported one case each in this location.

Postoperative average angular value of the curves was 50.44^o, below of the reported by Winter et al. (1973)³⁰ with 74^o. The measurement of the curves grades the severity of the kyphosis. So, Winter et al (1973)³⁰ understand that curves below 55^o are less severe. This fact influences the choice of surgical technique.

By clinical examination it was found in our series that all curves were absolutely rigid, what is coincident with the literature (Winter et al. 1977³⁰; Montgomery e Hall, 1982²⁰, Vialle e Alcântara, 1989²⁸).

Plain two views radiographs were used in all cases and served as a diagnosis investigation method, as type of kyphosis classification and as evaluation of the results. Kyphosis classification was based on that from Winter et al. (1973)³⁰. According to this classification, we observed twelve cases type I, three type II and one single case as type III.

Planigraphy was used as next investigational step when doubts remained after plain radiograph in regard of type of congenital defect. This took place in case # 13 where we observed a missing body of the new thoracic vertebra. This resource is recommended by Dewald and Ray, 1971⁵; Winter et al., 1973³⁰; Willians et al., 1982²⁹.

CT scan was performed in 12 of the 16 cases, so contributing for differentiating from formation and segmentation vertebral body defects. Willians et al. (1982)²⁹ used CT reporting in four cases presence of dorsal hemi-vertebrae not evidenced in plain radiographs. In our series, reduction of vertebral canal diameter, pediculae hypoplasia and discal herniation were the abnormalities observed in CT scans and not detected by means of plain radiographies.

Excretor urographies, performed in three cases, and urinary system ultrasonoagraphic evaluation in 13 cases was used in preoperative period, since there are references to association between these abnormalities and congenital deformities of spine and pelvian ectopies (figure 31). Similarly, Morin et al. (1985)²¹ reported one case of renal abnormality in a series of 16 cases of congenital kyphosis.

As a premise for treatment it is fundamental to know the natural history of congenital kyphosis. Winter et al. (1973)³⁰ found that type I congenital kyphosis usually increases seven degrees per year. The curve increases more rapidly during the years of fastest growth, and may be complicated by paraplegia. They also observed that curves type II progress in average five degrees per year ¾ what was also found by Mayfield et al., 1980¹⁷. Due to this unpropitious evolution, authors unanimously agree that treatment should be as early as possible, among them, James (1955)¹³; Winter et al (1973)³⁰; Montgomery and Hall (1982)²⁰ and Winter and Moe (1982)³³. Similarly they also agree that posterior vertebral arthrodesis has been shown to be an efficacious method when applied as early as above mentioned.

The use of posterior vertebral arthrodesis, specifically for treatment of congenital kyphosis, was first performed by Hanson (1926)⁹. James (1955)¹³ believes that MILWAUKEE splint could be efficacious for curve control during the first years, however indicates surgery whenever a curve progression is observed; and as well recommends primary surgery in the most severe cases. In this series of 16 cases here exposed, no splinting was used as treatment. We agree with Winter and Moe (1982)³³ who consider splinting as inefficacious for control of this deformity. Posterior vertebral arthrodesis should be early performed, avoiding curve progression and preventing an eventual paraplegia. This principle was adopted by us, and we submitted case 1 to surgery at the age of 1 year and six months. Kyphosis was 65^o and after a 12 years follow-up, reduced to 30^o. This improvement is explained by the posterior growth impairment provided by the arthrodesis, while anterior vertebral growth was allowed, favoring reduction of the deformity.

Posterior vertebral arthrodesis has been accepted as an effective treatment method for spinal deformities (Risser, 1964²⁴; Risser, 1966²⁵; Riseborougth, 1967²²). The technique we used was as modified by Moe (1958)¹⁹ and includes fusion of zigoapophyseal joints and of transverse processes also. We used autogenous grafting or homologous iliac grafting, aiming to place enough amount of cancellous bone at the top of the curve (figure 16). This is recommended by Goldstein (1969)⁷ aiming to implement healing. In a similar way as James (1955)¹⁷, Winter et al. and Montgomery and Hall (1982)²⁰ we performed the arthrodesis involving the kyphotic curve, two vertebrae above and two below the congenital defect.

Risser-Cotrel cast (Risser, 1961²³,) was used in this series in postoperative period during six months, a comparable time to the reported by Mayfield et al. (1980)¹⁷ and Montgomery(1955)¹³ and Hall (1982)²⁰. Walking was allowed to patients one day after the cast model was applied. We agree with Harrington (1972)^10, Leider et al. (1975)¹⁵, Mir et al. (1975)¹⁸, Erwin et al (1976)⁶, Winter et al. (1979)³² and Basile (1985)¹ to whom walking stimulates bony graft integration.

Regarding the results we adopted the pre and postoperative radiographic evaluation as proposed by Winter et al (1985)³⁴, since we understand this to be an efficacious and easy to perform method. Based on this radiographic criteria, we had 62.5% of good results, what means that in a minimum follow-up of two years we got decrease or stabilization of the curve. Regular results were 25%, what means that there was an increase of the curve up to 10^o or pseudarthrosis. It was observed that good results were more frequently observed among the most recently operated patients, explained by the learning curve and an earlier treatment of the patients.

In the observed series, a correlation between age and results of posterior vertebra arthrodesis did not show significant differences. Nevertheless, clinical observation suggests that patients who underwent surgery at lower ages had a higher trend to good results.

A correlation between the results and the types of congenital defects is prejudiced due to the vast majority belongs to type I (75%), versus 18.7% of type II and 6.15% of the mixed type. Winter et al. report that in type II kyphosis, due to lack of segmentation of vertebral bodies, posterior vertebral arthrodesis produces better results. In the same way, by clinical observation, we notice this trend, however without an statistical support.

Correlation between results and location of the curves is also prejudiced since the majority of the curves was thoracolumbar (68.75%). Even though no statistically significant difference was observed, those with thoracic curves had better results.

Correlation between degree of the curve and the results did not show any statistically significant difference. On the other side, considering the average of the curves of patients with good and poor results, we observe that they were 49.4^o and 68.5^o respectively. Clinical observation thus suggests that patients who undergo surgery with smaller curves look to have a trend to obtain better results, as it was also observed by Winter and Moe (1985)³⁴.

In regard of results distribution in each type, there was no change in relation to the time of follow-up. It is worthy to say that results kept their quality in all evaluated periods.

Even it was not statistically significant, average of kyphotic angular values postoperatively was inferior to preoperatively, showing that posterior vertebral arthrodesis is an efficient method not only for stabilization, but also for improvement of the curve.

In regard of complication, the most fearful is paraplegia, that can be due, among other causes, to the natural evolution of an untreated congenital kyphosis, mainly in type I cases (with high thoracic location) during the growth sprint as found by James (1955)¹³, Winter et al (1973)³⁰. Other causes would be medullar trauma during the surgery and the effect of the correcting instruments over the medulla. In this series we did not use correcting forcers since we believe that there is a frequent association between congenital abnormalities of central nervous system and congenital deformities of the spine (Hood et al., 1980)¹² that, under traction could lead to a neurological injury. Our objective was to get a posterior vertebral fusion at the level of the curve in order to avoid progression of the deformity during growth. We had no paraplegia as a complication.

Infection, when present, is also an important complication. Winter et al. (1973)³⁰ report 10.76% of infection. Mayfield et al. (1980)¹⁷, Winter and Moe (1982)³³ and Winter et al (1985)³⁴ did not have infection as a complication, and the same was found in our series. Only one patient required drainage of an haematoma in the second postoperative day. Not placement of instruments, vacuum suction drainage and improvement of asepsis techniques are contributing factors for explaining the low infection rates.

Pseudarthrosis is another possible complication. This should be early diagnosed before the deformity progresses. Winter et al. (1973)³⁰ have the opinion that the percentage of pseudarthrosis increases as the severity of the curve worsens in their series, where 80% of the cases had curves ranging from 50 to 100^o and had 51.7% of pseudarthrosis.

In the cases here evaluated, we had 6.5% of pseudarthrosis (one case) and the average preoperative kyphosis was 50.44%. Patient number 8, who had pseudarthrosis had a 69^o preoperative kyphosis, underwent revision of the arthrodesis in the 8^th postoperative month, obtaining its consolidation, and the curve, in the last follow-up was 61^o. We believe that the indication of arthrodesis in curves below 55^o and the placement of enough grafting on the apex of the curve (Goldstein)⁷ reduces the incidence of pseudarthrosis.

CONCLUSIONS

1- Posterior vertebral arthrodesis is a suitable method for the treatment of congenital kyphosis since taking into consideration the evidence that better results are linked to lower ages and curves with lower degrees of kyphosis.

2- Posterior vertebral arthrodesis is a low morbidity method.

8. GREIG, D. M. Congenital kyphosis. 1=-dimbur@gh Medical Journal,N.S., V16, p.93,1916 apud WINTER, R.B., p.224,1973.

Trabalho recebido em 02/05/2002. Aprovado em 17/05/2002

Work performed at Instituto de Ortopedia e Traumatologia do Hospital das Clínicas - FMUSP e no Serviço de Ortopedia da Universidade Federal do Piauí.

• 1. BASILE JR., R. Tratamento cirúrgico das escolioses idiopáticas no adolescente pelo método de Harrington. S.Paulo, 1985.Tese (Doutorado) - Fac. Med. U.S.P.
• 2. BERGOIN, M.; SEDAT, P.; LESBROS, A.- MERMET, B.; CARCASSONE, M. Nouvelle approche therapeutique dansle redressement chirurgides cyphoscoliosis congenitales delénfant. Marsseille Chir., V21, p.379-86, 1986.
• 3. BINGOLD, A.C. Congenital Kyphosis. J.Bone Jt Surg., V 35-B,p.579-83, 1953.
• 4. COBB, J.R. Outline for the study of scoliosis. ln: instructional Courses Lectures. The American Academy of Orthopaedic Sur-qeons V5, p. 261-75, 1948.
• 5. DEWALD, R.; RAY, R. Congenital kyphosis with suecessfull treatment. J. Bone Jt Surg., V53-A, p.587-90, 1971.
• 6. ERWIN, W.D.; DICKSON, J.H.; HARRINGTON, P.R. The post-operative management of scoliosis patients treated with Harrington instrurmentation and fusion. J.Bone Jt Surg., V58-A, p.479-82, 1976.
• 7. GOLDSTEIN, L.A. Treatment of idiopíithie scoliosis by Harrington instrumentation and fusion with 1'resh autogenous iliac bonegrafts. J. Bone Jt Sung., V51 -A, p.209-21, 1969.
• 9. HANSON, R. Some anornalies, deformities and diseased conditions of the vertebrae during their different stages of development. Elucidated by anatomia and radiological findings. Acta Chirurgica Scandiravica, V60, p.309, 1926.
• 10. HARRINGTON, P. R. Technical (letails in relation to the suecessfull use of instrumentation in scoliosis. Orthop. Clin.N. Amer., V3, p.40-67, 1972.
• 11. HODGSON, A. R. Correction of fixed spinal curves. J. Bone Surg., V.47-A, p.1221-27, 1965.
• 12. HOOD, R.W.; RISEBOROUGHT; NEHME, A.M.- MICHELI;1 STAND, R.D.; NEUHAUSER, E.D. Diastematemyelia and structural spinal deformities. J. Bone Surq., V62, p.520-28, 1980.
• 13. JAMES, J.I.P. Kyphosis. J. Bone Jt Surg., V37, p.414-26, 1955.
• 14. LEATHERMAN, K.D.; DICKSON, R.A. Two-stage corretive surgery for congenital deformities of the spine. J. Bone Jt Surg.,V61-B, p. 532-50,1979.
• 15. LEIDER, L.L.- MOE, J.H.- WINTER, R.B. Early ambulation after11 the surgical treatment of idiopathie scoliosis. J. Bone Jt Surg.,V55-A, p. 1003-15, 1975.
• 16. LOMBARD, P.; GÉNISSEL, L.E. Cyphosis congenitalis. Rev.Orthop., V25, p. 532-50, 1938.
• 17.MAYFIELD,J.K.-WINTER,R.B.;BRADFORD,D.S.-MOE, J.H.11 Congenital kyphosis due to defects of anterior segmentation. Orthop. Transections, V 27, 1980.
• 18. MIR, S.R.; COLE, J.R.; LORDONE, J.; LEVINE, D.B. Early ambulation following spinal fusion and , Harrington instrumentation in idiopathie scoliosis. Clin. Orthop., V110,p.54-62, 1975.
• 19. MOE, J. H. A criticar analysis of methods of fusion for scoliosis: an evolution of the hundred and sixty-six patients. J. Bone Jt Surg., V40-A, p.529-54,1958.
• 20. MONTGOMERY, S.P.; HALL, J. E. Congenital kyphosis. Spine,V7, p.360-64, 1982.
• 21. MORIN, B.; POITROS, B.; MORRIS, D.; RIVARD, H.C.; MARTIN, D. Congenital kyphosis by segmentation defect: etiologic and iathrogenic studies. J.Ped. Orthop., V5, p.309-14, 1985.
• 22. RISEBOROUGHT, E.J. Treatment of scoliosis. New Eng. J. Med. ,V276, p.1429-31, 1967.
• 23. RISSER, J.C. Plaster body - jackets. Amer. J. Orthop., p.1 9-23,1961.
• 24. RISSER, J.C. Scoliosis: past and present. J. Bone Jt Surg., V.46-A, p. 1 67-99, 1964.
• 25. RISSER, J.C. Treatment of scoliosis during the past 50 years. Clin. Orthop., V44, p.109-13, 1966.
• 26. SAVINI, R.; CERVALLATI, S.; CIONI, A.; PONZOL. Cifosicongênita: 11 Parte. 11 Tratamento cirúrgico. Le cifose,Bologna: Aulo Gagi Editore, 1982, p.203-17, 1982.(Proecedings of the ltalian Group of the Study of Scoliosis).
• 27. SHIBA, R.; MUROTA, K.; KONDO, H.; HONMA, G. Cervical congenital kyphosis with at antoaxial dislocation. Spine, V 1 8,p. 762-63, 1993.
• 28.VIALLE, L. R.; ALCANTARA, A.T Anomalias congênitas da coluna vertebral (cifose e escoliose congênitas): revisão de 81 casos.Rev. Brasileira de Ortopedia, V.24, n.11112, p.383-87, 1989.
• 29. WILLIAMS, F.; MEGALL, W.J.; O'BRIEN, P.J., MARK, M.W.Severe kyphosis due to congenital dorsal hemivertebra.Clinical Radioloqy, V.33, p.445-52,1982.
• 30. WINTER, R.B.- WANG, J.F. Congenital Kyphosis. lt's natural 2 history and treatment as observed in a study of 130 patients.J. Bone Jt Surg., V.55-A, p.223-56, 1973.
• 31. WINTER, R.B.; HALL, J.E. Kyphosis in childhood and adolescence. Spine, V.3, p.285-308, 1978.
• 32. WINTER, R.B. Posterior spinal fusion in scoliosis: indications, technique and results. Orthop. Clin. N. Amer: V.10, p. 787-800, 1979.
• 33. WINTER, R.B.- MOE, J.H. The results of spinal arthrodesis for1 congenital spine deformity in patients younger than 5 years old. J. Bone Jt Surg., V. 64-A, p.419-32, 1982. 77.
• 34. WINTER, R.B., MOE, J.H.; LONSTEIN, J.E. The surgical treatment of congenital kyphosis. A review of 94 patients age 5 years or older, with 2 years of more follow-up in 77 patients. Spine, V. 1 0, p. 224-31, 1985.
• 35. WINTER, R.B. Editorial: Congenital spine deforrnity: "What's thelatest and what's the best ?" Spine. V. 14, p. 1406-08, 1989.
• 36. WINTER, R.B. The treatment of spinal kyphosis. International Orthop.. V 5, p. 265-71, 1991.

Address for correspondence

Rua Pires Goyoso, 140

Teresina - Piauí

Publication Dates

• Publication in this collection
  25 Feb 2003
• Date of issue
  Sept 2002

History

• Accepted
  17 May 2002
• Received
  02 May 2002