Objective:To compare the clinical effects of hip arthroplasty through direct anterior approach (DAA) in lateral decubitus in the treatment of hip osteoarthritis caused by Kaschin-Beck disease and congenital acetabular dysplasia.Methods:The prospective study method was used to select the patients who needed hip arthroplasty in the Fourth Department of Orthopedics, the Second Affiliated Hospital of Harbin Medical University from January 2015 to December 2019. All of them were operated with lateral decubitus DAA. According to the inclusion criteria, they were divided into Kacshin-Beck disease hip osteoarthritis group (group A) and congenital acetabular dysplasia hip osteoarthritis group (group B). Hip Harris score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, visual analogue scale (VAS) score were conducted, and hip abduction angle and flexion angle were measured before surgery, 3, 14 days and 1, 3, and 12 months after surgery.Results:Nineteen and twenty-two patients were included in group A and group B, respectively. All patients successfully completed the surgery. There was no significant difference in Harris score between the two groups before surgery, 3, 14 days, and 1, 12 months after surgery ( P > 0.05). There were no significant differences in WOMAC score, VAS score, hip abduction angle and hip flexion angle between the two groups before surgery and each time point after surgery ( P > 0.05). In the same group, there were significant differences in Harris score, WOMAC score, VAS score, hip abduction angle and hip flexion angle at different time points ( P < 0.001). All postoperative indicators were significantly improved compared with those before surgery. Conclusions:There is no significant difference in the clinical effects of hip arthroplasty through lateral decubitus DAA in the treatment of hip osteoarthritis caused by Kaschin-Beck disease and congenital acetabular dysplasia. This surgical method has good therapeutic effect on both types of hip osteoarthritis.

Kashin-Beck disease (KBD) is a disabling osteoarthropathy of unknown cause, which occurs most frequently in children and adolescents and affects many regions in China. In adults KBD patients, the degeneration of weight-bearing joints is the most serious, especially the knee joint. Up to now, there are still a large number of adult patients with KBD arthritis of the knee, and they have not been systematically and effectively treated. The main manifestations are knee joint pain, thickening, deformation and restricted movement. In severe cases, it can lead to knee joint varus, valgus, flexion contracture, and rotational deformity, which seriously affects the quality of life and work ability of the patients. Early diagnosis of KBD arthritis of the knee is difficult and there is no effective treatment, so it needs to be differentiated from knee osteoarthritis (OA). KBD and OA have common pathological characteristics. According to the "Consensus of Four-stepladder Program of Knee 0steoarthritis" (2018), OA treatment is divided into four levels: basic treatment, drug treatment, restorative treatment and reconstruction treatment. In this paper, the treatment of KBD arthritis of adult knee joint is summarized, which is also divided into four steps. It is necessary to make stepwise treatments according to the severity of KBD arthritis of the knee and the differences of patient's own condition, so that the limited medical resources can be efficiently used. At the same time, this paper also systematically summarizes the epidemiological characteristics, pathological features and diagnostic criteria of KBD arthritis of the knee, aiming to provide effective reference and guidance for the treatment of KBD arthritis of the knee.

Objective:To compare the efficacy of arthroscopic anterior cruciate ligament reconstruction using tendon autograft with figure-of-four position and traditional knee hyperflexed position for femoral tunnel creation.Methods:A retrospective case series study was conducted to analyze the clinical data of 46 patients with ACL injury admitted to Second Affiliated Hospital of Harbin Medical University from August 2019 to October 2019, including 26 males and 20 females; aged 24-40 years [(31.1±7.5)years]. All patients underwent arthroscopic ACL reconstruction using tendon autograft. The femoral tunnel was created with figure-of-four position in 21 patients (figure-of-four position group) and with traditional knee hyperflexed position in 25 patients (knee hyperflexed position group). The operation time was compared between the two groups. The center position, length and angle of femoral tunnel were evaluated and measured by three dimensional CT reconstruction and Bernard quadrant method at 8 weeks postoperatively. The knee function was assessed by knee Lysholm score preoperatively, at 8 weeks and at 1 year postoperatively. Complications were observed as well.Results:All patients were followed up for 2-20 months [(15.3±2.1)months]. The operation time was (28.5±2.6)minutes in figure-of-four position group, significantly less than (39.5±2.4)minutes in knee hyperflexed position group ( P<0.05). The tunnel center position was located at (27.1±1.4)% and (25.1±2.6)% within the Bernard quadrant in figure-of-four position group, similar with (28.1±2.8)% and (26.1±3.1)% in knee hyperflexed position group (all P>0.05). Total tunnel length and thick tunnel length were (42.1±2.4)mm and (34.1±2.4)mm in figure-of-four position group, significantly longer than (38.2±2.5)mm and (31.1±2.7)mm in knee hyperflexed position group (all P<0.05). The coronal plane angle of the tunnel was (41.1±2.4)° in figure-of-four position group, significantly smaller than (47.5±2.6)° in knee hyperflexed position group ( P<0.05). The sagittal plane angle of the tunnel was (42.1±1.4)° in figure-of-four position group, significantly greater than (37.1±1.8)° in knee hyperflexed position group ( P<0.05). Figure-of-four position group showed the knee Lysholm score of (53.4±5.2)points preoperatively, (97.1±1.4)points at 8 weeks postoperatively and (98.3±2.3)points at 1 year postoperatively. Knee hyperflexed position group showed the knee Lysholm score of (54.3±7.4)points preoperatively, (97.1±1.6)points at 8 weeks postoperatively and (98.1±1.3)points at 1 year postoperatively. The knee Lysholm score did not differ significantly between the two groups (all P>0.05), but the knee function was significantly improved in both groups when compared with that before the operation (all P<0.05). There were 1 patient with femoral tunnel fracture, one with injury to the medial condylar cartilage and one with injury to the posterior root of lateral meniscus in knee hyperflexed position group, while no above-mentioned complications occurred in figure-of-four position group ( P<0.05). Conclusion:Arthroscopic ACL reconstruction using tendon autograft with femoral tunnel creation through figure-of-four position and traditional knee hyperflexed position can both contribute knee functional recovery, but the figure-of-four position has the advantages of short operation time, accurate tunnel positioning, favorable length and angle of the tunnel and less complications.