Objective To evaluate more than 5-year follow-up outcome of avulsion fracture of the anterior cruciate ligament from the tibial insertion site in skeletally immature patients treated with modified arthroscopic internal fixation with cannulated screw and washer. Methods Thirty-nine patients with open physis were treated by modified arthroscopic internal fixation with cannulated screw and washer from March 2000 to November 2003. Regular X-ray plain films at AP and lateral views were conducted to detect the healing of avulsed fragments. Follow-up period of 31 patients was more than 5 years. Functional outcome before and after surgery was evaluated using the Lysholm Knee Score and the Tegner Activity Score. Angular deformity, or leg length discrepancy was assessed by clinical examination and anteroposterior-lateral radiographs of the knee. Instrumented knee laxity was performed using the KT-2000 arthrometer. Results Arthroscopic removal of implants was performed between 3 and 6 months postoperatively, when all fractures were revealed to have healed on X-ray films. No growth disturbance, angular deformation or knee instability was found in 31 patients during more than 5-year follow-up. The Lysholm score was improved from (19.2?14.8) (range 12-48) preoperatively to (98.5?3.1) (range 97-100) postoperatively, with significant statistical difference by the student-t test (t=18.395, P=0.000); The Tegner score was improved from (4.1?1.1) (range 3-5) preoperatively to (8.5?0.8) (range 7-9) postoperatively, with significant statistical difference by the student-t test (t=4.13, P=0.008). Physical examination showed Lachman test (+) in 14 of 31 patients. Instrumented knee laxity (KT-2000) showed manual-maximum side-to-side difference greater than 2 mm (range 2.1-3.8 mm) in 14 of 31 patients. Conclusion Modified arthroscopic internal fixation of avulsion fracture of the anterior cruciate ligament from the tibial insertion site with cannulated screw and washer in skeletally immature patients is a simple, safe, and effective ARIF procedure without growth disturbance.

Objective To explore the changes in early serum calcium,serum phosphorus,and calcium-phosphorus product levels in patients with fractures and analyze their correlation with the fracture site.Methods 1 049 patients with fractures admitted to Sichuan Province Orthopedic Hospital from January 2021 to November 2023 were selected as the research subjects.According to the fracture location,they were roughly divided into two groups:upper body fracture(n=478)and lower body fracture(n=571).Carefully divided into ten groups:vertebral fracture(n=108),clavicle fracture(n=109),upper limb fracture(n=106),hand fracture(n=104),femoral neck fracture(n=103),femoral intertrochanteric fracture(n=106),patella fracture(n=101),lower limb fracture(n=103),foot fracture(n=105)and other fractures(n=104).Another 110 cases of healthy physical examination people during the same period were selected as the control group.Venous blood was drawn from all patients twice on the day of emergency within 24 to 48 hours after admission,serum calcium and serum phosphorus were measured,and the calcium-phosphorus product was calculated.Compare the changes in the levels of the three and analyzed their correlation with the fracture site.Results Compared with the control group,the serum calcium(2.27±0.12 mmol/L,2.19±0.12 mmol/L vs 2.35±0.10mmol/L),serum phosphorus(1.00±0.20mmol/L,1.08±0.19mmol/L vs 1.15±0.15mmol/L),and calcium-phosphorus product(28.10±6.00mg/dl,29.30±5.85mg/dl vs 33.41±4.87mg/dl)of fracture patients were all reduced on the day of emergency and 24 to 48 hours after admission,and the differences were statistically significant(t=6.804,12.501;7.475,3.722;8.964,7.115,all P＜0.01).Comparing upper and lower body fractures,serum calcium,serum phosphorus,and calcium-phosphorus product on the emergency day was lower in lower body fracture than in upper body fracture(t=4.129,5.931,6.660,all P＜0.01),24 to 48 hours after admission,only the serum calcium and calcium-phosphorus product were lower in lower body fracture than in upper body fracture(t=6.432,1.990,all P＜0.05),and the differences were statistically significant,respectively.Comparing along the time axis,24 to 48 hours after admission compared with the emergency day,both upper and lower body fractures showed a decrease in serum calcium and an increase in serum phosphorus(t=12.779,-5.730;16.919,-14.358),calcium-phosphorus product only increased in lower body fracture(t=-8.860),and the differences were statistically significant(all P＜0.01),respectively.Compared with the day of emergency,24 to 48 hours after admission for patients with fractures in different parts,except for vertebral fracture,serum calcium in the other nine groups decreased(t=6.233～11.349,all P＜0.01),except for upper limb fracture and hand fracture,the serum phosphorus in the other eight groups increased(t=-7.770～-3.327,all P＜0.01),the calcium-phosphorus product of vertebral fracture,femoral neck fracture,femoral intertrochanteric fracture,lower limb fracture,foot fracture,and other fractures increased(t=-5.819～-2.927,all P＜0.01),and the differences were statistically significant,respectively.Conclusion The serum calcium,serum phosphorus,and calcium-phosphorus product of patients with fractures all decreased on the day of emergency.24 to 48 hours later,the serum calcium of most patients continued to decrease while the serum phosphorus and calcium-phosphorus product gradually increased.The degree of change in their levels was related to the fracture site.