ABSTRACT
Objective:To compare the clinical effect of cannulated lag screw combined with calcaneal locking plate versus cannulated lag screw in the treatment of Letenneur type III Hoffa fracture.Methods:A retrospective cohort study was performed on clinical data of 41 patients with Letenneur type III Hoffa fracture admitted to General Hospital of Central Theater Command of PLA from January 2010 to June 2020. There were 22 males and 19 females, aged 28-78 years［(51.9±1.9)years］. A total of 18 patients were treated with cannulated lag screw combined with calcaneal locking plate (plate-screw group) and 23 patients were treated with cannulated lag screw (screw group). The bed rest time, hospital time and bone healing time were compared between the two groups. Range of motion (ROM) of the knee at 3 and 6 months postoperatively, knee society score (KSS) at 3 and 6 months postoperatively and incidence of long-term complications were compared between the two groups.Results:All patients were followed up for 10-24 months［(14.5±2.1)months］. The bed rest time was (37.6±2.4)days in plate-screw group, lower than (45.2±1.6)days in screw group ( P<0.05). The hospital time was (16.7±3.7)days in plate-screw group, and (15.8±3.7)days in screw group ( P>0.05). The bone healing time was (12.2±0.9)weeks in plate-screw group and (12.7±0.7) weeks in screw group ( P>0.05). ROM of the knee at 3 and 6 months after operation was (119.9±2.9)° and (125.4±4.5)° in plate-screw group, greater than (116.6±4.5)°and (122.1±3.9)° in screw group (both P<0.05). KSS at 3 and 6 months after operation was (83.4±3.1)points and (86.2±2.5)points in plate-screw group, greater than (79.5±2.1)points and (82.2±2.2)points in screw group (both P<0.05). ROM of the knee and KSS in two groups increased significantly over time (both P<0.01). The long-term complications in plate-screw group included delayed fracture healing in 1 patient, traumatic arthritis in 1 and stiff joint in 1, showing the complication rate of 17% (3/18). The long-terem complications in screw group included internal fixation failure in 1 patient, delayed fracture healing in 2, nonunion in 1, traumatic arthritis in 2 and stiff joint in 2, showing the complication rate of 35% (8/23). The two groups had no significant difference in the complication rate ( P>0.05) .Conclusion:For Letenneur type III Hoffa fracture, cannulated lag screw fixation combined with calcaneal locking plate is superior to seperate cannulated lag screw fixation in aspects of short bed-term bed rest, early functional exercise, improved ROM and good function recovery.