Objective To explore surgical techniques and clinical effects of arthroscopic absorbable interference screw fixation and four-stranded hamstring tendon autograft for the reconstruction of anterior cruciate ligament (ACL). Methods Forty-two patients with rupture of the ACL were operated on by arthroscopic four-stranded hamstring tendons autograft reconstruction using SR-PLLA absorbable screw fixation. Results Follow-up for 3～22 months (mean, 11 4 months) in all 42 patients showed normal motion range of knee joint. Postoperative Lachman test revealed ≤1+ in 37 patients, 2+ in 4 patients and 3+ in 1 patient. All patients showed an absent pivot shift. Postoperative Lysholm score was 89 7?9 6 points, which had increased significantly as compared with the preoperative score (49 4?9 1 points; t =2 12, P =0 038). Postoperative Tegner activity grading scale was 5 3?1 1 points, which was significantly higher than the preoperative one (2 3?0 7 points; t =4 13, P =0 008). MRI examination at first postoperative year showed that absorbable interference screws were partly absorbed in 29 patients,and reconstructed ligaments were in good position and normal in shape in 27 patients.The tendon grafts were anchored on the femur a little too more to the front side in 2 patients, and on the tibia a little too more to the front side in 3 patients, with slight impingement phenomena. Conclusions In ACL reconstruction, four-stranded hamstring tendon is an ideal graft material and absorbable interference screw is optimal for internal fixation.

Objective:To compare clinical effects of the open versus closed high tibial osteotomy on knee osteoarthritis.Methods:A total of 100 patients with knee osteoarthritis admitted to our hospital from May 2018 to May 2019 were included.They were randomly divided into groups A and B(n=50, each group)according to the principle of random and double blind.Patients in group A received the medial opening high tibial osteotomy, and group B were treated with lateral closed high tibial osteotomy.The changes in the Lysholm knee score, hospital for special surgery(HSS)knee score and complications were compared between the two groups before and 1 year after surgery.The correction angle, the change of patella height before and after operation, and the change of posterior slope of tibial plateau were compared between the two groups.Results:Before and after treatment, Lysholm scores were(63.51±5.47)and(90.98±5.84)( t=24.275, P=0.000), and HSS scores were(51.85±4.68)and(88.64±5.87)( t=34.652, P=0.000). Lysholm scores were(62.98±6.14)and(91.52±6.54 9)( t=22.497, P=0.000), and HSS scores were(52.05±5.16)and(89.54±5.15)( t=36.362, P=0.000)in group A and B, .After treatment, all index were significantly improved in the two groups, but there was no statistical difference between the two groups( P>0.05). In group A, the posterior slope of tibial plateau were(8.75±1.48)° and(10.25±1.65)°( t=4.785, P=0.000)and the patellar height was(0.890±0.031)and(0.898±0.032)( t=1.270, P=0.207)before and after treatment.Before and after treatment in group B, the posterior slope of tibial plateau were(8.69±1.53)° and(5.26±1.21)°( t=12.434, P=0.000)and the patellar height were(0.889±0.047)and(0.821±0.039)( t=7.873, P=0.000). The correction angle, posterior slope of tibial plateau and patella height were significantly improved after treatment in the two groups.While, the decreases of posterior slope of tibial plateau and patella height were better in the group B than in the group A( P<0.05). There was no significant difference in the incidence of complications between the two groups( P>0.05). Conclusions:For treatment of knee osteoarthritis patients, the medial opening high tibial osteotomy and lateral closed high tibial osteotomy have the same exact effect and high safety, but the two methods have their own advantages and disadvantages in clinical treatment.And the appropriate surgical treatment can be selected according to the characteristics of patients.

OBJECTIVETo identify a rare α-thalassemia gene mutation in a family from south China and perform a pedigree analysis and genetic diagnosis of hemoglobin H (HbH) disease caused by this mutation.

METHODSPeripheral blood samples were collected from the family members for analysis of the hematological phenotype and routine test of thalassemia genes. DNA sequencing was carried out for samples that showed genotype and phenotype inconsistency.

RESULTSA rare α-thalassemia *92A>G gene mutation was detected within this family. The proband and his sister were confirmed to have non-deletional HbH disease with α--/αα genotype. The proband's brother was confirmed to have an α-thalassemia trait with the genotype of -α/αα. The proband's father was identified as an α-thalassemia silent carrier with the genotype of αα/αα.

CONCLUSIONA rare α-thalassemia *92A>G gene mutation was identified for first time in south China. The description of the basic phenotypic characteristics of α-thalassemia trait and silent carrier caused by this mutation enriches the α-thalassemia gene mutation spectrum in Chinese population and helps in population screening, clinical molecular diagnosis and genetic counseling.