Treatment of femur pseudoarthrosis using wave plate: Evaluation of consolidation and its relationship with graft type.

INTRODUCTION: In the pathogenesis of femoral pseudoarthrosis, the arched shape of the bone is important when determining traction force on the anterolateral plane and posteromedial compression. In plate osteosynthesis, flexion forces affect the implant and can determine its breakdown and osteosynthesis failure. The wave plate seeks to solve the problem by transferring the support to the cortex under the plate or creating the resistance of a leaf spring. OBJECTIVES: To evaluate the bone healing pattern of femoral pseudoarthrosis treated with wave plate and its effectiveness in consolidation. MATERIALS AND METHODS: We retrospectively evaluated 18 patients with femoral pseudoarthrosis treated with wave plate. RESULTS: Three months after surgery, one patient presented healing of pseudoarthrosis, six months after surgery, 16 patients presented healing of pseudoarthrosis and at 12 months, all patients had complete bone healing. Regarding the type of pseudoarthrosis, nine patients had avascular and nine vascular pseudoarthrosis. Fifteen patients had medial cortical failure and three, lateral cortical failure. In all cases, consolidation started where there was bone failure, be it medial or lateral. DISCUSSION: The wave plate technique is well indicated for the existence of cortical bone failure, both in fractures and in pseudoarthrosis. Objective is to stabilize the fragments by transferring and allowing contact between them. The formation of the bone callus occurred in our sample from the region of the bone defect to the region of bone contact, using either a tricortical or cancellous bone graft. The elastic force of the wave and the eccentric distribution of loads in the femur favored the formation of a callus where it was distracted (bone failure) and the location with concentration of movement (proximity between the fragments) was the end of bone healing. CONCLUSION: The wave plate technique was effective in bone healing of femoral pseudoarthrosis, promoting consolidation from the cortical failure to the bone contact zone.

Supra-acetabular fixation and sacroiliac screws for treating unstable pelvic ring injuries: preliminary results from 20 patients / Tratamento das lesões instáveis do anel pélvico com fixador supra-acetabular e parafusos sacroilíacos: resultados preliminares em 20 pacientes

OBJECTIVE: To analyze the treatment results from 20 patients who underwent an alternative osteosynthesis method as definitive treatment for pelvic ring fractures. METHODS: A retrospective analysis was conducted on a series of 20 patients with pelvic ring fractures (Tile type C) and a high risk of postoperative infection, who were treated at Santa Casa de Misericórdia de São Paulo between August 2004 and December 2012. The patients underwent percutaneous supra-acetabular external fixation in association with cannulated 7.0 mm iliosacral screws. RESULTS: The patients' mean age was 40 years (range 22-77 years) and the mean length of follow-up was 18.5 months (range 3-69 months). At the end of the treatment, ten patients (50%) were classified as having good results, nine patients (45%) had fair results and one patient (5%) did not have any improvement. Six patients presented complications, and paresthesia of the lateral femoral cutaneous nerve was the most frequent of these (two patients). CONCLUSION: Supra-acetabular external fixation in association with iliosacral percutaneous osteosynthesis is a good definitive treatment method for patients with a high risk of postoperative infection.

OBJETIVO: Avaliar os resultados do tratamento de 20 pacientes que usaram como tratamento definitivo um método de osteossíntese opcional para fraturas do anel pélvico. MÉTODOS: Foi feita uma análise retrospectiva da série de 20 casos de pacientes com fratura do anel pélvico tipo C de Tile, portadores de alto risco de infecção pós-operatória, tratados na Santa Casa de Misericórdia de São Paulo entre agosto de 2004 e dezembro de 2012, submetidos a fixação externa supra-acetabular percutânea associada com parafusos canulados iliossacrais de 70 mm. RESULTADOS: A média de idade dos pacientes foi de 40 anos (mínimo de 22; máximo de 77) e o tempo médio de seguimento foi de 18,5 meses (mínimo de três; máximo de 69). Após o término do tratamento dez pacientes (50%) foram classificados com bons resultados, nove (45%) tiveram desfecho regular e um (5%) não apresentou melhoria alguma. Seis apresentaram complicações. A parestesia do nervo cutâneo femoral lateral foi a mais frequente (dois pacientes). CONCLUSÃO: A fixação externa supra-acetabular associada a osteossíntese percutânea iliossacral é um bom método de tratamento definitivo para os pacientes com alto risco de infecção pós-operatória.