1.1 general data: retrospective analysis of patients with VAO who received osteotomy and orthopedic treatment in Affiliated Hospital of Chengdu University from July 2014 to July 2020. Inclusive criteria: 45–65 years old, varus ankle arthritis, anterior tibial angle (TAS) ≤ 85 °, Takakura classification stage II-III [6], tibiotalar articular cartilage preservation > 50%, simple coronal varus deformity, supramalleolar opening or fornix osteotomy correction. Exclusion criteria [8]: Previous peri ankle fracture or deformity surgery history, severe medial ankle wear requiring intra-articular osteotomy, Takakura stage IV ankle arthritis, posterior foot instability unable to recover through ligament reconstruction, genu derived ankle varus, peri ankle infection, severe vascular and neurological diseases, Charcot osteoarthritis.
Thirty eight patients were included in this study, including 31 males and 7 females, 21 left ankles and 17 right ankles. According to the osteotomy methods, they were divided into two groups: fornix osteotomy (FOT) group (n = 17, male 14, female 3, mean age 60.59); open osteotomies (OOT) group (n = 21, male 17, female 4, mean age 60.86). The general information of the two groups is shown in Table 1. There is no significant difference in gender composition, age, height and body mass index, anterior ankle osteophyte and other general information between the two groups (P > 0.05).
Table 1
Comparison of general data between supramalleolar open osteotomy and fornix osteotomy
|
Supramalleolar open osteotomy(n = 17)
|
Open osteotomy group(n = 21)
|
P
|
Gender(F /M)
|
3/14
|
4/17
|
1.000
|
Age(Y)
|
60.59 ± 1.80
|
60.86 ± 1.49
|
0.618
|
Left and right side(L/R)
|
10/7
|
11/10
|
0.750
|
Body mass index(kg/m2)
|
20.94 ± 1.68
|
21.29 ± 1.45
|
0.502
|
Takakura classification(Ⅱ/Ⅲ)
|
7/10
|
7/14
|
0.740
|
OA/TOA
|
4/13
|
9/12
|
0.307
|
Diabetics
|
3/14
|
4/17
|
1.000
|
Smoking
|
3/14
|
8/13
|
0.282
|
Anterior ankle osteophyte(with/without)
|
14/2
|
18/3
|
1.000
|
1.2 Treatment:
1.2.1 Preoperative preparation: Smoking patients strictly prohibit smoking after hospitalization, diabetic endocrinology consultation to help control blood sugar. (1) Clinical examination: standing position assessment of the overall lower limb strength line, recording the patient's ankle active and passive activity, local pain position, inside and outside, front and rear drawer experiments to clarify ankle stability. (2) Imaging examination: preoperative X-ray examination includes the full length of double lower limb weight, ankle weight positive side position, rear foot weight long axis (long axial view radiographs) (10); Clinical determination of ankle arthritis malformation site, type, CORA position, back foot force line, external ankle ligament relaxation degree after determining the surgical program.
1.2.2 Surgical method: lumbar or full hemp, recline position, the affected limb with inflatable hemostatic belt (pressure 260 mmHg, 34.66Kpa), hemostatic belt inflated 30 minutes before the intravenous application of antibiotics to prevent infection.
(1) Open osteotomy group (Fig. 1): Surgery using the ankle inside the arc inlet, sharp separation of the inner ankle above the bone membrane, the front and back edge of the tibia inserted Hohmann pull hook to protect the tibia front and rear nerve blood vessel bundle. (1) 10mm into 2 2mm kT needles on the ankle line to protect the far end joint surface of the tibia. (2) Place the bone-osteotomy guide needle, 3cm above the inner ankle line into the needle facing down the joint above the phospheric joint 1cm. (3) After accurate perspective positioning, a pendulum saw cut bone is used at a depth of 2cm. (4) The thin bone knife slowly amputated the bone, the perspective determines the distance from the fibula of the tibia cut 5mm part, insert the step bone knife gradually open, retain the hinge lateral bone tissue continuity. (5) ankle front side position, rear foot long axis X-ray perspective to determine the force line, generally maintain with the bone outside the turn of 5 degrees, the outer end of the shin bone joint surface turned 3 degrees by the inner ankle front and rear mound into the knuckle needle temporary fixation, bone cut gap > 10mm filled with allogeneic bone implants, placement of the inner anatomy locked steel plate (High, Shandong). After the internal fixation is completed, the ankle roll-over and front drawer experiments, such as external ankle instability, are reinforced with improved Brostrom rivet repair techniques. Open osteotomy group patients did not do fibula osteotomy, do not place drainage, stitch the wound, thick dressing covering the wound, elastic bandages pressurized bandage.
(2) Fornix osteotomy group (Fig. 2): the use of ankle front and center inlet, along the 踇 long extension and toe extension tendon gap into, the inner side pull to protect the front nerve blood vessel bundle, open the ankle sac, clean the front ankle, bone - inner ankle, outer ankle gap, bone neck growth bone. Local cartilage dressing and micro-fracture molding from joint de-variant line. Sharp separation of the upper bone membrane of the ankle, the inner and outer sides of the tibia inserted Hohmann pull hook to protect soft tissue. (1) Placement of bone-osteotomy guide needle: the CORA point located under the ankle or away from the bone is positioned at 5mm on the ankle line, into a 2.5mm kT needle to determine the center of the fornix-cut bone rotation. (2) fornix osteotomy: placement of the collar needle locator, using a diameter of 2.5mm drill bit for ankle fornix osteotomy, bone radius of 3cm; (3) Outer ankle osteotomy: 1 to 2 cm above the arc extension line of the tibia fornix to carry out fibula osteotomy (note to protect the lower tibia joint), remove 5mm bone segment, bite bone pliers crushed into particle bone pieces after partial filling back planting. (4) Rotating orthopaedics: self-heeled bone into the 4mms needle, fixed heel-distance-shin bone far end, external rotation correction of the tibia far end joint surface deformity. (5) the front side position, rear foot long axis X-ray perspective determined after the foot outside the turn of 5 degrees, the placement of pressurized screws and the far end of the front tibia anatomy locked steel plate (Vigao, Shandong), the outer ankle osteotomy is not fixed. External ankle ligament instability repair technology, wound stitching technology and the inner open bone osteotomy.
Postoperative treatment: anesthesia wakes up immediately after the beginning of lower limb muscle contraction exercises, limb elevation promotes swelling and subsidence, encourages ankle stretching activity, drug anticoagulant prevention of deep vein thrombosis, open bone osteotomy 6 weeks after surgery, fornix osteotomy 2 weeks after the start of partial weight-taking activities, X-ray review prompts bone osteotomy after the start of full weight activity and gait exercise.
1.3 clinical follow-up: Monthly outpatient review and record the American Orthopedic foot and ankle score (FAS) ankle and hindfoot score [15]. Three months after the operation, the weight-bearing ankle acupoints and lateral X-ray examination were performed. I. X-ray measurement indexes of ankle acupoints: (1) tibial anterior surface angle (TAS): the angle between the distal articular surface of tibia and the medial side of tibial mechanical axis [16]. (2) Talar tilt angle (TTA): the angle between the articular surface of distal tibia and the surface of talar vault. (3) Lateral talus migration (LTM) [17]: the distance between the mechanical axis of talus and that of tibia. II. Lateral measurements included: tibial lateral surface angle (TLS): the angle between the distal articular surface of the tibia and the anterior mechanical axis of the tibia. The imaging measurement was completed by the second author alone, and repeated 3 months later. The difference was ICC > 0.85.
1.4 statistical analysis: SPSS 19.0 software package was used for statistical analysis. The count data were compared by chi square test. Measurement data were expressed as mean ± standard deviation, and independent sample t test was used for comparison between groups. P < 0.05 was statistically significant.