RESUMEN

OBJECTIVE: The aim: This article aimed to evaluate biomechanical changes during the most commonly used pelvic osteotomies (Salter, Dega, Pemberton) for DDH treatment in pediatric patients. PATIENTS AND METHODS: Materials and methods: Virtual pelvic models of 2- and 6-years old patients were created, material properties were assigned, pelvic osteotomies were simulated and biomechanical changes were evaluated using finite element analysis (FEA). RESULTS: Results: It was revealed that the patient's age impacts pelvic bones and cartilage density (in younger patients the pelvic elements are more pliable - p<0.05). Stress distribution after each of the abovementioned pelvic osteotomy was assessed in 2- and 6-year-old patients' pelvic models. The new term "restriction point" was introduced, which means a place where restriction of acetabular deformity correction occurs. CONCLUSION: Conclusions: It was found that there are no purely reshaping and reorientation pelvic osteotomies as previously believed; the pelvic ring acts as a unit in carrying out the applied load. Biomechanical overload of triradiate cartilage during Salter osteotomy in 2-year-old patients and in 2- and 6-year-old patients during Pemberton osteotomy was revealed; overload of the posterior cortical layer in the greater sciatic notch in 2-years old patient during Dega osteotomy was revealed.

Asunto(s)

RESUMEN

OBJECTIVE: The aim: Establishment of the factors influencing the formation of femoral neck-shaft angles and femoral torsions indices among the patients with cerebral palsy. PATIENTS AND METHODS: Materials and methods: The total number of patients was 46 persons (84 joints). We have examined patients using our method (patent №137567), obtained the true parameters of the femoral neck-shaft angle and femoral torsion, and conducted a statistical analysis of factors that might influence their formation. RESULTS: Results: A statistically significant influence of factors of age, Gross Motor Function Classification System (GMFCS) level, ambulatory status, adductor myotomy and lack of statistical significance concerning the influence of factors such as level of lesion and developmental dysplasia of the hip upon the indices of neck-shaft angle. Femoral torsion's parameters were in statistically significant fashion affected by GMFCS levels, ambulatory status, level of lesion, and did not display statistical significance of factors of age, adductor myotomy, developmental dysplasia of the hip. CONCLUSION: Conclusions: Our research shows that gait function, as well as GMFCS level, are the important factors in the formation of the proximal femur in patients with cerebral palsy.

Asunto(s)

RESUMEN

Background: If non-surgical treatment of Developmental Dysplasia of the Hip (DDH) fails or if DDH is late-detected, surgery is necessary. Salter pelvic osteotomy (SPO) is an effective surgical option for such cases. Objectives: To study the results after SPO; to evaluate risk factors; to reveal radiological parameters that may correlate with results. Methods: Results analysis in 17 patients (22 hips). Risk factors included those that do not depend on the surgeon (patient's age, value of the acetabular index (AI) preoperatively, DDH Tonnis grade) and those that depend on the surgeon (amount of AI correction). To radiological parameters which may correlate with the amount of AI correction we referred distance "d" and the lateral rotation angle. Results: SPO allows performing AI correction in ranges 24.1 ± 6.5°. Excellent and good clinical results were obtained in 95.5% of patients; excellent and good radiological results in 86.4% of patients. Risk factors that do not depend on the surgeon were older patient's age and higher preoperative AI values (p <0.05). The risk factor that depends on the surgeon was the amount of AI correction (p <0.05). The distance "d" was recognized as a radiological parameter that may indicate sufficient AI correction (p <0.05). Conclusion: In older patients with a higher preoperative AI value the results will be predictably worse. The surgeon may influence the result with a greater amount of AI correction (which may also be indicated radiologically by the distance "d" values). Level of evidence: IV, therapeutic, case series.

RESUMEN

Objective: Three pelvic osteotomies (Salter, Dega, Pemberton) are widely used in walking patients under 7 years old for DDH treatment. We've proposed a modified Salter Pelvic Osteotomy (SPO), which has the advantages of the abovementioned osteotomies. Methods: Short- and mid-term results were assessed in 19 patients after modified SPO application. Patients were examined before and after the surgery, at 6 months postoperatively and at follow-up. Results: Acetabular Index (AI) before the surgery was 39.5 ± 7 °, after the surgery - 24.4 ± 5.5 °, at 6 months - 20.4 ± 5 ° (9-28), at follow-up - 14.5 ± 4 °; AI correction - 14.9 ± 5.5 °. Lateral Centre-Edge Angle at follow-up - 22.7 ± 4.7 °. Clinical results at follow-up were I / II McKay grade in 18 patients (94.7%); radiological results were  I / II Severin class in 18 patients (94.7%). Conclusion: Modified SPO allows to improve the FH coverage in any direction; results after modified SPO are excellent and good in the vast majority of patients. Level of Evidence IV, Case Series

Objetivo: Três osteotomias pélvicas (Salter, Dega, Pemberton) são amplamente utilizadas em pacientes que andam com menos de 7 anos para o tratamento de DDQ. Propusemos uma Osteotomia Pélvica de Salter (SPO) modificada, que tem as vantagens das osteotomias acima mencionadas. Métodos: Os resultados de curto e médio prazo foram avaliados em 19 pacientes após a aplicação de SPO modificada. Os pacientes foram examinados antes e após a cirurgia, aos 6 meses de pós-operatório e no seguimento. Resultados: O índice acetabular (IA) antes da cirurgia era de 39,5 ± 7 °, após a cirurgia - 24,4 ± 5,5 °, aos 6 meses - 20,4 ± 5 ​​° (9-28), no seguimento - 14,5 ± 4 °; Correção AI - 14,9 ± 5,5 °. Lateral angulo centro-borda no acompanhamento - 22,7 ± 4,7 °. Os resultados clínicos no acompanhamento foram grau I / II de McKay em 18 pacientes (94,7%); os resultados radiológicos foram classe I / II de Severin em 18 pacientes (94,7%). Conclusão: O SPO modificado permite melhorar a cobertura de FH em qualquer direção; os resultados após SPO modificado são excelentes e bons na grande maioria dos pacientes. Nível de evidência IV, série de casos

RESUMEN

BACKGROUND: Developmental dysplasia of the hip (DDH) is a common hip joint pathology seen in the pediatric orthopedist's practice. Pelvic osteotomies are the reliable surgical option for DDH treatment in walking patients, and 3 osteotomies (Salter, Dega and Pemberton) are widely used in patients under 6 years of age. Plastic changes in hinge points occur during iliac fragment movement, after the performed osteotomy. The locations of these points are described in the literature, but some debate still exists about their true positions. OBJECTIVES: To reveal hinge point locations during a simulation of pelvic osteotomies on biological models. MATERIAL AND METHODS: Eighteen piglet pelvis complexes were obtained and separated according to their age. Pelvic osteotomies were simulated, and bone changes were assessed on computed tomography (CT) scans after the performed surgeries. RESULTS: No bone changes were found after Salter osteotomy in younger piglets, while contralateral pubic bone metaphyseal fractures were found in older animals. After Pemberton osteotomy, greenstick fractures in iliac and pubic bones metaphyses in the triradiate cartilage area were revealed in younger and older piglets. After Dega osteotomy, a posterior medial cortical layer fracture of the uncut iliac bone in the greater sciatic notch was found in all piglets. In older piglets, an additional hinge point was detected in the ipsilateral pubic bone metaphysis. CONCLUSION: It was found that the age of the piglets has an impact on hinge point number and location, and this may be explained by an age-related decrease in pelvic bone and cartilage plasticity. The results of this study may help surgeons to decrease the number of preventable complications during pelvic osteotomies.

Asunto(s)