골다공증성 척추에서 척추경 나사못 고정력과 연관된 임상적 결과 - 합병증 및 예방 - = A Clinical Result of Pedicle Screw Fixation in Osteoporotic Spine - Complications and Prevention -

다국어 초록 (Multilingual Abstract)

Study Design: Retrospective study.
Objectives: To analyze the clinical results of patients who were treated by pedicle screw fixation in osteoporotic spine and suggest the methods for preventing a loss of fixation strength.
Summary of Literature Review: There are some methods to decrease failure rate and increase fixation strength in the osteoporotic spine: use bicortical screw, cement augmentation and supporting anterior column by interbody fusion using cages.
Materials and Methods: Forty-four patients treated by spinal instrumentation using pedicle screw from 2004 to 2011 were followed for at least 12 months. Five men and 39 women were diagnosed as osteoporotic spine (T score <-3.0). Two hundred forty eight pedicle screws were included and statistically analyzed the correlation between the use of bicortical screw, cement augmentation, anterior column support and fixation loss of the pedicle screw. Radiologic results were evaluated to find out the mechanical complications, like loosening of the screw, fixation failure, and nonunion.
Results: There were 9 complications associated with mechanical strength, loosening of pedicle screws in 7, sinking down of cage in 4, and nonunion in 4 cases. Using bicortical pedicle screw, cement augmentation and anterior column support were significantly correlated with the increasing fixation strength (P=0.001, P=0.047, P=0.014). In addition, these three factors contribute to stabilize the instrumentation (Linear by linear association, P=0.012).
Conclusions: These 3 methods, using bicortical pedicle screw, cement augmentation and supporting anterior column, are effective to enhance the fixation strength and prevent loss of holding power in the osteoporotic spine.

국문 초록 (Abstract)

연구 계획: 후향적 분석목적: 골다공증성 척추에 척추경 나사못을 삽입하여 고정술을 시행한 환자들의 임상적 결과를 분석하여, 합병증의 원인을 알아보고 예방법을 제시하고자 한다.
선행 문헌의 요약: 골다공증성 척추에서 나사못의 고정력을 높이고 실패율을 낮추기 위한 방법들로 전방 피질골을 관통하는 길이가 긴 척추경 나사못을 삽입하는 방법, 시멘트 충진술을 시행하는 방법, cage 등을 이용하여 전방주를 지지하는 방법 등이 보고되었다.
대상 및 방법: 2004년 6월부터 2011년 7월까지 척추경 나사못을 이용한 기기술 및 유합술을 시행받은 최소 12개월이상의 경과 관찰 기간을 가진 44례및 248개의 척추경 나사못을 대상으로 하였다. 모든 환자는 골다공증성 척추로 진단되었으며, 그 기준은 골밀도 -3.0 이하로 하였다. 248개의 척추경나사못에 대해서 긴 척추경 나사못의 사용과 시멘트 충진술의 시행 여부 및 척추 전방주의 지지 여부가 나사못의 고정력 상실과 관련이 있는지 분석하였다.
결과: 총 45례 중 9례에서 기기 고정력과 관련한 합병증이 발생하였다. 나사못 고정력 상실이 7례, cage의 침강이 4례, 불유합이 4례에서 관찰되었다.
긴 척추경 나사못의 사용과 시멘트 충진술의 시행 및 척추 전방주의 지지 여부는 나사못의 고정력 증가와 관련하여 통계적으로 유의하였다. (P=0.001,P=0.047, P=0.014). 또한 각각을 기기술의 안정화 인자로 보았을 때 안정화 인자가 많을수록 고정력과 관련한 합병증이 적게 발생하였으며, 이는 통계적으로 유의한 상관 관계를 보였다.(P=0.012)결론: 골다공증성 척추에서 기기술과 유합술을 시행하는 경우 내고정물의 고정력을 높이고 실패율을 낮추기 위해서 긴 척추경 나사못을 이용하고 시멘트 충진술을 시행 및 척추 전방주를 지지하는 고정력 상실 예방에 유용할 것으로 생각된다.

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