Nikolaou P K, Macdonald B L, Glisson R R, Seaber A V, Garrett W E
Am J Sports Med. 1987 Jan-Feb;15(1):9-14. doi: 10.1177/036354658701500102.
This study correlates force generation and healing in muscle after controlled strain injury. Right tibialis anterior (TA) muscles from 30 rabbits were strained to approximately 80% of failure while the left TA muscles served as control. Both injured and control muscles were then tested for ability to generate force. Seven animals were sacrificed immediately after testing and the muscles were examined grossly and histologically. Remaining animals were retested at 24 hours (N = 7), 48 hours (N = 8), and 7 days (N = 8). Contractile ability following injury was 70.5% of control immediately, 51.1% at 24 hours, 74.5% at 48 hours, and 92.5% at 7 days. Immediate histology showed limited distal fiber rupture and hemorrhage. By 24 hours, histology showed fiber necrosis, infiltration of inflammatory cells, edema, and hemorrhage. At 48 hours there was complete fiber breakdown and intense inflammatory cell proliferation. At 7 days inflammation was reduced and collagen fibrosis more advanced. Our findings demonstrate that injured muscle begins functional recovery by 48 hours despite inflammation and active healing. This suggests that decreasing muscle function seen clinically between 24 and 48 hours following strain injury may result from pain due to inflammation. Scarring and fibrosis seen at 7 days may explain the frequent recurrence of injury to strained muscles.
本研究关联了可控性应变损伤后肌肉中的力量产生与愈合情况。选取30只兔子的右侧胫骨前肌（TA）施加应变，使其达到约80%的破坏应变，而左侧TA肌作为对照。然后对受伤和对照肌肉的力量产生能力进行测试。7只动物在测试后立即处死，对肌肉进行大体和组织学检查。其余动物在24小时（N = 7）、48小时（N = 8）和7天（N = 8）时再次进行测试。损伤后的收缩能力在即刻为对照的70.5%，24小时时为51.1%，48小时时为74.5%，7天时为92.5%。即刻组织学检查显示远端纤维有有限的破裂和出血。到24小时时，组织学显示纤维坏死、炎性细胞浸润、水肿和出血。48小时时出现完全的纤维崩解和强烈的炎性细胞增殖。7天时炎症减轻，胶原纤维化更明显。我们的研究结果表明，尽管存在炎症和积极愈合，受伤肌肉在48小时时开始功能恢复。这表明在应变损伤后24至48小时临床上观察到的肌肉功能下降可能是由炎症引起的疼痛所致。7天时出现的瘢痕形成和纤维化可能解释了应变肌肉损伤频繁复发的原因。
