Mitochondrial myopathy is a group of multi-system diseases in which mitochondrial DNA(mtDNA)or nuclear DNA(nDNA)defects lead to structural and functional dysfunction of mitochondria.The clinical manifestations of mitochondrial myopathy are complex and varied,and the testing for mtDNA and nDNA is not widely available,so misdiagnosis or missed diagnosis is common.Chronic progressive external ophthalmoplegia(CPEO)is a common type of mitochondrial myopathy,which is characterized by blepharoptosis.Here we report a 38-year-old female with mitochondrial myopathy presented with chronic numbness and weakness of the limbs,accompanied by blepharoptosis that was recently noticed.Laboratory and head magnetic resonance imaging(MRI)examinations showed no obvious abnormalities.Muscle and nerve biopsies showed characteristic ragged red fibers(RRFs)and large aggregates of denatured mitochondria.Testing for mtDNA and nDNA showed a known mutation c.2857C＞T(p.R953C)and a novel variant c.2391G＞C(p.M797I)in the polymerase gamma(POLG)gene,so the patient was diagnosed as mitochondrial myopathy.Clinicians should pay more attention to long-term unexplained skeletal muscle diseases with recent onset blepharoptosis.Histopathologic examination and genetic testing are of great value in the early diagnosis and therapeutic intervention.

Objective To investigate the clinical efficacy of arthroscopic simple repair technique and en-hanced repair technique in the treatment of chronic lateral ankle instability(CLAI).Methods Forty-one cases of CLAI treated in the General Hospital of Northern Theater Command of PLA from January 2018 to January 2019 were selected and conducted arthroscopic lateral ankle ligament repair or enhanced repair treatment.The follow up data in 39 cases were complete.Among them,18 cases conducted the anterior talofibular ligament repair with wire anchor under arthroscopy and were included in the repair group,while 21 cases conducted the arthroscopic enhanced repair with linear anchors and knots free anchors and were included in the enhanced re-pair group.The postoperative follow up lasted for 12 months.The VAS score and AOFAS ankle-hind foot score before operation and in postoperative,3,6,12 months were compared between the two groups.The effi-cacies of treating CLAI by the two operation modes were evaluated.Results The preoperative VAS score and AOFAS ankle-hind foot score had no statistical differences between the two groups(P＞0.05).The VAS score at postoperative time points had no statistical difference between the enhanced repair group and repair group(P＞0.05).The AOFAS ankle-hind foot score in the enhanced repair group was higher than that in the repair group,and the difference was statistically significant(P＜0.05).No serious complications occurred in the grouped patients during the follow up period.Conclusion In terms of pain and ankle function,the effect of arthroscopic enhanced repair in treating CLAI is better than that of simple repair.