2.1 Patient selection
Inclusion criteria: 1) Proximal tibial fracture; 2) Can tolerate surgery, and knee joint movement function was normal before this injury; 3) The fracture occurred within 1 week of surgery; 4) Agreed to participate in the study and sign an informed consent form; and 5) Patients with follow-up time ≥ 12 months.
Exclusion criteria: 1) Pathological fracture; 2) Severe osteoporosis; 3) Patients with a history of mental illness; 4) Obvious surgical contraindications; 5) Patients with compartment syndrome; 6) Open fractures of Gustilo–Anderson class II and above; 7) Vascular injury patients; 8) Patients with narrow medullary cavity (intramedullary nails cannot be used); 9) Patients with open osteophytes; and 10) Patients with tibial deformity and those whose tibia cannot be fixed with intramedullary nails.
2.2 General information
This study prospectively analyzed 36 cases of proximal tibial dry fractures admitted to the Department of Trauma and Orthopaedics, Xi'an Honghui Hospital from January 2013 to January 2017. Sealed envelopes encoded according to computer randomization order were randomly grouped for the patients under study. The envelopes were opened by a roving nurse after the patient entered the operating room, to inform the surgeon which internal fixation method to adopt. The patients who received the traditional approach of intramedullary nail and small plate internal fixation was classified as the “steel plate” group, and the internal fixation with the barrier nail technique was classified as the “barrier nail” group. The preoperative general information of the two groups of patients is shown in Table 1. There was no significant difference in age, gender, injury factors, and fracture types between the two groups (P>0.05)。This study was approved by the ethics committee of this unit, and all patients provided signed, informed consent.
2.3 Surgical procedure
2.3.1 Subgingival approach, intramedullary nail, adjunct plate
Plate group: Under general anesthesia, the patient is placed in a supine position, and the affected side is raised. Make an incision of about 6 cm in length at the fracture site of the proximal and posterior side of the calf, and make a layer-by-layer incision to expose the fractured end. Be careful not to strip the periosteum in a large area. The anatomical relationship of the fracture reduction can be distinguished. Use after reduction under direct vision After shaping, the 5 to 6-hole 3.5 mm system reconstruction locking bone plate is placed on the posterior medial side of the tibia, and the single cortical locking screws are screwed in in turn. After fluoroscopy confirms the reduction and fixation position is satisfied, close the incision. Then use the anterior inferior patella approach, split the patellar ligament in the middle, clear the subpatellar fat pad, and expose the tibial plateau slope. Before the opening of the medullary cavity, the correct nail entry point should be determined under fluoroscopy. This operation is particularly important. The correct entry point should be located at the anterior midline of the cartilage, slightly higher than the tibial tubercle[5]. Use an opener to make a hole in the direction of the guide pin, insert the reamed long guide pin, select the appropriate intramedullary nail and place it along the guide pin after stepwise reaming, and try to make the tip of the tibial intramedullary nail close to the articular surface of the distal tibia. Perform the interlocking nails at the far and near ends. After the far and proximal ends are locked, the tail cap is installed, the saline is flushed, the drainage tube is left, and the incision is sutured layer by layer.
2.3.2 Blocking nail technology
Blocking nail group: The patient is placed in a supine position, and the affected side is raised. Split the patellar ligament in the middle, clear the subpatellar fat pad, and expose the slope of the tibial plateau. Before the opening of the medullary cavity, the correct nail insertion point should be determined under fluoroscopy. Use an opener to make a hole in the direction of the guide pin, insert a finger reducer, and fluoroscopy. Correct the lateral position, remove the finger reducer according to the angled inside and outside of the broken end and the front and back angles, and drill a 2.5 mm Kirschner wire in the proper position as a temporary stop nail, insert the finger reducer again, and see through the broken end. Adjust the position of the blocking nail when the inside and outside of the broken end are angled and the front and back angles. The following steps are the same as the steel plate group.
2.4 Postoperative treatment
All patients were given cephalosporin antibiotics to prevent infection and limb elevation
for 24 to 48 hours. X-ray films were reviewed on the second day after surgery, and patients were encouraged to perform primary and passive functional exercises on the knees, ankles, and toes. CPM (Joint function training machine) machines were used to assist exercise if necessary. Anterior and posterior radiographs of the affected tibia were taken after the drainage tube was removed the day following surgery. Wound dressings were removed after two weeks. The patients were followed up once a month for the first three months after the operation, every 3–6 months after 3 months, and every 6–12 months after 1 year. The X-ray film showed that the affected limbs were partially loaded after the formation of the callus, and were completely loaded after the fracture end was healed.
2.5 Observation index and efficacy evaluation
The operation time, the number of intraoperative fluoroscopy, the cost of surgical consumables, the length of hospital stay and early complications were recorded in the two groups of patients; the clinical results were evaluated by the time of ground movement, the time of full weight bearing, the range of motion of the knee joint and the Johner-Wruhs rating. Perform imaging examinations and use Freedmanand Johnson's method to measure tibia coronal and sagittal angulation deformities, namely: varus and valgus deformity on the coronal plane and anteroposterior angulation deformity on the sagittal plane, and angulation on any plane >5° is regarded as poor reset [6]. Record the fracture healing time. At the last follow-up, the therapeutic effect was evaluated according to the Johner-Wruhs tibial shaft fracture postoperative evaluation standard[7]. as follows: Excellent: good fracture healing, no neurological and vascular complications, no internal and external valgus deformity, anterior and posterior angle <5°, rotational shift angle <5°, shortening <5 mm, normal knee and ankle joint activity, subtalar joint activity degree >75%, no pain, normal gait, unlimited exercise; Good: fractures healed well, mild vascular nerve stimulation, internal and external turning angle <5°, anterior and posterior angle <10°, rotational shift angle <10°, shortening <10 mm, knee joint mobility >80%, ankle joint mobility >75%, subtalar joint mobility >50%, occasional pain, normal gait, limited exercise; Fair: fractures healed well, moderate blood vessels, nerve stimulation, internal and external angles <10°, anterior and posterior angles <20°, rotational displacement <20°, shortening <20 mm, knee mobility >75%, ankle joint mobility >50%, subtalar joint mobility <50%, moderate pain, mild lameness, severe exercise is severely restricted; Poor: fracture not healed or bone infection, amputation, severe vascular nerve stimulation, internal and external angulation angle >10°, anterior and posterior angle >20°, rotational displacement >20°, shortening >20 mm, knee joint activity degree <75%, ankle joint activity <50%, severe pain, obvious claudication, cannot do vigorous activity.
2.6 Statistical analysis
Statistical analysis was performed using IBM SPSS 19.0 statistical software (SPSS, USA). The homogeneity of variance is expressed by`x ± s. Two independent sample t-tests were used to compare the two groups. The rate was compared using the χ2 test, and P < 0.05 was considered to be statistically significant.