Muscle Strength of Operated and Non-operated Knees Following Unilateral Total Knee Arthroplasty in Female Patients — A Prospective Study

單側人工漆關節置換手術之女性患者其雙側膝肌力研究—前瞻性報告

王淑芬(Shwu-Fen Wang)；詹美華(Mei-Hwa Jan)；楊榮森(Rong-Sen Yang)；劉堂桂(Tang-Kue Liu)

人工膝關節置換手術 ； 膝肌力 ； 屈肌／伸肌比值 ； Total knee arthrophasty ； Muscle strength ； Flexor/extensor ratio

物理治療

29卷1期（2004 / 02 / 01）

1 - 8

英文

Background and purpose: Changes in knee muscle strength and flexor/extensor(hamstrings/quadriceps; H/Q)ratio for operated knees have been reported in patients following two years of unilateral total knee arthroplasty (TKA).Whether muscle strength of the kness shows changes in patients before and after TKA remains unclear. This study was to compare the muscle strength and H/Q ratios between the operated and the non-operated knees in female patients before TKA operation and six months after operation. Methods: Eighteen female patients participated. Each patient was tested for maximal torque of knee extensors and flexors bilaterally, at 30°and 60°of knee flexion pre-operatively and six months after operation. Results: The isometric extensor torques of both knees tested at 30°of flexion were increased at six months following operation(p＜0.05).The isometric flexor torques of both knees at 30°and 60°of flexion also showed increase at six following operation(p＜0.05).However, the muscle strength and H/Q ratio of the two knees remained unequal at six months post-operation (p＜0.05). Conclusion: The significant increase in muscle torque of both extensors and flexors might be resulted from gradual reduction of pain and chronic inflammation after surgery. However, significant weakness of the extensor and flexor of the operated knee compared to the non-operated knee at six months post-operation may relate to some other potential factors preventing a full restoration of knee strength after the operation. Further investigation in this area is needed.

Background and purpose: Changes in knee muscle strength and flexor/extensor(hamstrings/quadriceps; H/Q)ratio for operated knees have been reported in patients following two years of unilateral total knee arthroplasty (TKA).Whether muscle strength of the kness shows changes in patients before and after TKA remains unclear. This study was to compare the muscle strength and H/Q ratios between the operated and the non-operated knees in female patients before TKA operation and six months after operation. Methods: Eighteen female patients participated. Each patient was tested for maximal torque of knee extensors and flexors bilaterally, at 30°and 60°of knee flexion pre-operatively and six months after operation. Results: The isometric extensor torques of both knees tested at 30°of flexion were increased at six months following operation(p＜0.05).The isometric flexor torques of both knees at 30°and 60°of flexion also showed increase at six following operation(p＜0.05).However, the muscle strength and H/Q ratio of the two knees remained unequal at six months post-operation (p＜0.05). Conclusion: The significant increase in muscle torque of both extensors and flexors might be resulted from gradual reduction of pain and chronic inflammation after surgery. However, significant weakness of the extensor and flexor of the operated knee compared to the non-operated knee at six months post-operation may relate to some other potential factors preventing a full restoration of knee strength after the operation. Further investigation in this area is needed.