- 期刊
Changes in the Biomechanical Function of the Gastro-Soleus Complex after Simulated Calcaneal Fracture: A Cadaveric Study
模擬跟骨骨折後腓腸—比目魚肌生物力學功能之變化
摘要
本實驗之目的在評估跟骨錯位性骨折，其長度與高度改變之後，肥腸-比目魚肌施力狀況改變之情形，我們利用八個鮮新下肢截肢標本研究。每個標本固定於倒立狀態，在蹠骨頭部懸掛1公斤之重量，而阿基里德氏肌腱聯結到一張力量測器，以便紀錄跟腱上所需使用的張力多少。首先將跟骨做橫向切骨術，每次移去5mm，直至20mm為止，測量在不同脛足角度，跟腱所施之吏，接著用內固定術將取下骨片固定回去，再在跟骨前後兩端做直向切骨術，每次減少張度5mm，直至20mm，同樣量測不同脛足角度時，跟腱所施之力，實驗結果顯示在自然脛足角度時，跟骨高度每減少5mm，跟腱施力約需增加2%，然而在跟骨長度減少5，10，15與20mm時，跟腱施力增加各為22%，42%，65%與97%。由以上結果，我們建議在跟骨骨折的手術復位時，除了關節面的整復之外，跟骨的形狀，尤其是長度，也要注意矯正回來，以免影響腓腸-比目魚的功能。
關鍵字
無資料並列摘要
The purpose of this study is to evaluate the forces across the gastro-soleus complex after changes in calcaneal height and length as would occur in displaced calcaneal fracture. Eight fresh-frozen specimens were utilized. Each specimen was mounted in an in verted configuration with a cemented intramedullary rod in the tibia. A 1-kg weight was suspended from the metatarsal heads, and the Achilles tendon was connected to a strain gauged force transducer. Then force on the Achilles tendon required to balance the foot in different tibio-pedal angles was then recorded for various surgical changes in calcaneal geometry. The calcaneal height was decreased by 5-mm increments by sequential osteotomies and removal of the osteomized blocks. The maximum decrease in height created was 2 cm. After obtaining the strain readings for the corresponding heights, the osteomized blocks were replaced and fixed in their original position using hardware . The length of the calcaneus was decreased by osteomizing and removing 5-mm blocks from the proximal and distal aspect to a maximum decrease in length of 2 cm. Forces on the Achilles tendon were again recorded for each decrease in calcaneal length. At neutral foot position, 2- degree of plantar flexion, and 10 degree of dorsiflexion, each 5-mm decrease in calcaneal height caused an approximate 2% increase in the force on the Achilles tendon. The sequential decrease in calcaneal length of 5, 10, 15, and 20 mm resulted in an increase of forces on the Achilles tendon of 22%, 42%, 65%, and 97%, respectively. For open reduction of calcaneal fractures, in addition to restoration of joint congruency, calcaneal dimensions, especially length, should be restored to minimize the loss of function of the gastro soleus complex.