[Case-control study on the effect of meniscus shaping on knee function after anterior cruciate ligament reconstruction].

OBJECTIVE: To observe the effect of the meniscus shaping on the knee function and stability after anterior cruciate ligament reconstruction(ACLR).

METHODS: A total of 64 ACLR patients were included from January 2013 to January 2015. The control group was the ACLR patients with intact meniscus, in which 24 males and 6 females. The mean age was(32.8±5.5) years old(ranged, 22 to 43 years old). The injury side was left on 17 cases and right on 13 cases. The mean follow-up time was(15.2±2.8) months(ranged, 12 to 19 months). The shaping group was the ACLR patients with meniscus shaping, in which 27 males and 7 females. The mean age was (33.1±4.2) years old (ranged, 23 to 42 years old). The injury side was on the left in 22 case and right in 12 cases. The mean follow-up time was (16.0±3.1) months (ranged, 12 to 20 months). The preoperative anterior tibia shift and knee joint function, as well as anterior tibia shift, knee joint function and active proprioception at last follow-up time were observed. The anterior tibia shift was measured by KT-1000. The knee joint function was assessed by Lysholm score and KOOS score. The errors of active proprioception were measured at 30°, 45° and 60° knee flexion.

RESULTS: Postoperative anterior tibia shift of the affected side was (1.4±0.2) mm, which was lower than (2.2±0.4) mm in shaping group( P <0.05). The postoperative total Lysholm scores of the control group and the shaping group were 93.7±2.7 and 92.3±3.0 respectively, which were higher than 52.8±3.9 and 51.6±5.1 preoperatively( P <0.05), but there were no significant differences between two groups( P >0.05). In the KOOS score, the postoperative symptoms, pain, daily life, exercise capacity and life quality in control group were 90.7±5.5, 93.2±4.3, 96.8±2.2, 90.9±5.3, 91.8±4.5 respectively, which were higher than 72.7±6.0, 70.6±7.3, 72.5±7.4, 52.8±5.4, 36.2±6.5 preoperatively( P <0.05); the postoperative symptoms, pain, daily life, exercise capacity and life quality in the shaping group were 88.9±5.8, 92.6±3.5, 96.5±2.1, 89.3±7.2, 90.6±4.1 respectively, which were higher than 71.9±5.1, 71.2±7.1, 71.3±6.2, 53.1±6.1, 35.6±4.7 preoperatively( P <0.05). No significant differences were observed in each postoperative item of KOOS between the two groups( P >0.05). No significant differences were observed in the postoperative active proprioception error of contralateral side between the control group(12.2±3.4)°and shaping group(12.8±3.2)°( P >0.05). The error of active proprioception in the affacted side of the control group was(13.5±3.7)°, which was lower than that in the shaping group(17.1±4.2)°( P <0.05). In control group, there was no significant difference in the active proprioception error between two sides( P >0.05). While in shaping group, the error of active proprioception in the affacted side was significantly greater than that in the contralateral side( P <0.05).

CONCLUSIONS: In short and medium term, meniscus shaping has no effect on knee joint function in patients with ACLR, but it impairs the knee proprioception and stability.