Usefulness of Contralateral Indirect Decompression through Minimally Invasive Unilateral Transforaminal Lumbar Interbody Fusion

STUDY DESIGN: Retrospective study. PURPOSE: This study aims to investigate the clinical and radiological results of contralateral indirect decompression through minimally invasive unilateral transforaminal lumbar interbody fusion (MI-TLIF). OVERVIEW OF LITERATURE: Several studies have proposed that blood loss and operation time could be reduced through a unilateral approach, although many surgeons have forecast that satisfactory foraminal decompression is difficult to achieve through a unilateral approach. METHODS: The study included 30 subjects who had undergone single-level MI-TLIF. Visual analogue scale (VAS) and Oswestry disability index (ODI) were analyzed for clinical assessment. Disc height, segmental lordosis, and lumbar lordosis angle were examined for radiological assessment. The degree of contralateral indirect decompression was evaluated through a comparative analysis, with a magnetic resonance imaging (MRI) performed preoperatively and at one year postoperatively. RESULTS: Intraoperative blood loss volume was 308.75 mL in the unilateral approach group (UAP), and 575.00 mL in the bilateral approach group (BAP), showing a statistically significant difference. Operation time was 139.50 minutes in the UAP group, and 189.00 minutes in the BAP group, exhibiting a statistically significant difference (p0.05). CONCLUSIONS: Satisfactory results were acquired with MI-TLIF conducted through the unilateral approach of contralateral indirect decompression, in alignment with the bilateral approach. Therefore, contralateral indirect decompression is thought to be a useful procedure in reducing the operation time and volume of blood loss.

Difference of Fusion Rate in Minimally Invasive Transforaminal Lumbar Interbody Fusion with Autobone and Hydroxyapatite according to Mixture Ratio and Amount of Bone Graft / 대한정형외과학회잡지

PURPOSE: The aim of this study is to analyze the fusion rate according to the mixture ratio and the amount of bone graft in minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). MATERIALS AND METHODS: This study included 92 subjects who underwent MI-TLIF. Patients were classified into either group I, in which patients received transplantation with only autogenous bone, group II, in which patients received transplantation with hydroxyapatite mixed with autogenous bone by more than 50%, or group III, in which patients received transplantation with hydroxyapatite mixed with autogenous bone by less than 50%. For analysis of the correlation of amount of bone graft with fusion rate, patients were divided into group A, having less than 12 ml of bone graft, and group B, having more than 12 ml of bone graft. Visual analogue scale and Oswestry disability index were used for clinical assessment, and Burkus' classification method was used for evaluation of bone fusion. RESULTS: Fusion rates of groups I, II, and III according to the mixture ratio were 90.9%, 86.5%, and 86.2%, respectively. The fusion rate increased as the autobone ratio became higher; however, no significant difference was found (p=0.16). The fusion rates were 81.5% and 92.5% in group A and group B, respectively, which were classified according to the volume of bone graft, showing a significant increase in groups with bone graft volume more than 12 ml (p=0.03). CONCLUSION: A significantly high fusion rate was observed when bone graft volume was more than 12 ml in MI-TLIF. More than 12 ml of bone graft volume is essential for achievement of a satisfactory fusion rate.

Deformity Correction by Femoral Supracondylar Dome Osteotomy with Retrograde Intramedullary Nailing in Varus Deformity of the Distal Femur after Pathologic Fracture of Giant Cell Tumor

Angular deformities of the distal femur occur in congenital diseases or due to acquired causes, such as malunion after a fracture of the distal femur. Angular deformities of the lower extremities affect the mechanical axis, causing changes in the weight pressure on the articular surface. As a result, angular deformities quicken the progression of osteoarthritis. Therefore, correction of deformities should be performed to prevent the progression of osteoarthritis. Distal femoral osteotomy is one of the methods to correct angular deformities in unicompartmental osteoarthritis. However, femoral supracondylar dome osteotomy with retrograde intramedullary nailing in the distal femur with a varus deformity has been rarely reported. Herein, we describe a technique for femoral supracondylar dome osteotomy with retrograde intramedullary nailing in a varus deformity after a pathologic fracture of giant cell tumor in the distal femur with a review of the relevant literature.