1.1.Patients, Materials
There were 21 patients, 15 males and 6 females, aged 28-56 years, with an average age of 37.2 years. The causes of injury included: 10 cases of foot sprain, 5 cases of traffic accident, and 6 cases of hard object injury (Tab.1).
Table 1 Characteristics of the study population
Age ,year, mean (range)
|
37.2 (28 -56 )
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Male,n (%male)
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16 (76.1)
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Smoking,n (%)
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10 (47.6)
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Laterality,n(%)
|
|
Right
|
14 (66.7)
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Left
|
7 (33.3)
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Diabetes,n (%)
|
2(9.5)
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Herscovici classification,n(%)
|
|
Type B
|
8(38)
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Type C
|
13(61.9)
|
Follow-up, months,mean (range)
|
12.5(8-15)
|
The inclusion criteria were as follows: (1) Herscovici B.C medial malleolus fracture within one week of injury, (2) The fracture ends have obvious separation and rotational displacement. The exclusion criteria were as follows: (1) Old fracture,(2)Severe cardiovascular and cerebrovascular diseases that cannot tolerate operation, (3) Open wounds or other fractures of the foot and ankle, (4) Herscovici B.C medial malleolar fracture.
The preoperative examination included anteroposterior and lateral position of ankle radiography. Three-dimensional CT scan of ankle must be conducted to further evaluate the diagnosis. The CT evaluation should include the type of fracture, the degree of displacement, and the size of the fracture fragments (Fig 1).
1.2 Surgery
The patient received epidural anesthesia, taken a supine position and routinely applied a tourniquet. Arthroscopic equipment was installed. Generally, the observation portal was the anterolateral portal, and the operation portal was the anteromedial portal or the auxiliary anteromedial portal located 1.5cm was below the anteromedial portal. Skin incision was made. The capsule was separated and penetrated into the joint cavity. A 4.0 mm.30 degree wide-angle lens was connected. The ankle cavity was explored. After systematic 21-point inspection to evaluate joint parts, observe the damage of ligament and cartilage damage.
The fractured fragments of medial malleolus fracture were exposed. The hematoma, fascia and blood clot embedded in the fracture fragments were removed with blue pliers to assure that there was no fascia insertion between the fracture fragments.
The reduction process under ankle arthroscopy monitoring includes the following steps: First, use clamps to axially pull the medial malleolus to the distal end to facilitate observation of the displacement of the fractured end. Then lift the distal fragment from the ventral side to restore the sagittal line. Second, use clamp as a lever to adjust the rotational malformation of the fracture fragments. Finally, push the fracture fragments to the proximal end to promote the connection of the fractured ends of the medial malleolus, and use the joystick clamp to make fine adjustments to accomplish anatomical reduction.
Under fluo-roscopic control, two guide wires pass through the fracture site percutaneously from the top of the medial malleolus. Then, screw two 4.5 mm cannula screws along the two guide wires through the fracture site. Take care to avoid under-compression or over-compression between fragments, Confirm the position of the screws through arthroscopy and fluo-roscopic to ensure that they do not stand out from the articular surface and maintain an anatomical reduction(Fig.2)
1.3Arthroscopic findings
Arthroscopy was found in cartilage lesions in 12 (57%) of 21 patients, 10 of which were located in the dome of the talus and 2 patients were located in the distal tibia. On the basis of the ICRS arthroscopic grading system, 7 are grade 1 and 5 are grade 2. Shavingand removing debris and worn cartilage or microfractures under arthroscopy respectively. No patients have combined tibiofibular syndesmosis or other ligament injuries.
1.4 Postoperative management
The next day after the beginning of the ankle joint active and passive range of motion (ROM), partial weight-bearing was allowed 3 weeks after surgery, 6 weeks after surgery can not completely weight-bearing, limit physical activity within 3 months.
Patients from July 2018 to October 2020 were followed up for 2 weeks, every month to 6 months, and 1 year.
1. 5 Outcome measures
The main result of the measures the American Orthopedic Foot and Ankle Society after foot (AOFAS) ankle scoring system to evaluate ankle function. 90-100 divided into excellent, 75-89 divided good , 50-74 divided into general, <50 was poor[14]. It was assessed at the 6 months and 1 year follow-up. The subordinate result of the measures the visual analog scale (VAS) and radiologic assessment. The VAS score was decided at 3 days and 2 weeks after the surgery. Radiographs were obtained immediately after surgery and every month until the fracture is healed