Objective To investigate the effect of knee suspension during titanium plate fixation on postoperative posterior tibial slope (PTS) in knee osteoarthritis (KOA) with medial opening-wedge high tibial osteotomy (OWHTO). Methods The clinical data of 47 patients with KOA treated by OWHTO between January 2019 and December 2020 was retrospectively analyzed. In 24 cases, the knee joint was suspended when titanium plate was fixed (research group), and in 23 cases, the knee joint was naturally straightened when titanium plate was fixed (control group). There was no significant difference in gender, age, side, body mass index, disease duration, preoperative visual analogue scale (VAS) score, American Hospital for Special Surgery (HSS) score, Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score, Lysholm score, and preoperative PTS between the two groups (P>0.05). PTS were measured at 1 day after operation and last follow-up, and were compared with that before operation. Before operation and at last follow-up, VAS score was used to evaluate the knee pain, HSS score, WOMAC score, and Lysholm score were used to evaluate the knee function. Results The patients in both groups were followed up 13-24 months, with an average of 19.9 months. There was no complication such as incision infection, screw fracture, and deep venous thrombosis of lower limbs in two groups. At last follow-up, the VAS score, HSS score, WOMAC score, and Lysholm score in two groups were significantly improved when compared with those before operation (P<0.05), but there was no significant difference between the two groups in the each score difference of before and after operation (P>0.05). There was no significant difference in PTS at each time point before and after operation in the research group (P>0.05), but PTS in the control group significantly increased at 1 day after operation and last follow-up (P<0.05). PTS of the research group at 1 day after operation and last follow-up were significantly lower than those of the control group (P<0.05). ConclusionOWHTO can effectively relieve knee pain and improve knee function in KOA, and the increase of postoperative PTS can be effectively avoided by suspending knee joint.
ObjectiveTo summarize the management principle and clinical suggestions of the osteotomy gap of opening wedge high tibial osteotomy (OWHTO).MethodsThe related literature of the osteotomy gap of OWHTO in recent years was reviewed, summarized, and analyzed.ResultsDelayed union and non-union of the osteotomy gap are main complications of OWHTO. Tomofix plate, as locking steel plate, has the characteristics of angular stability and can better maintain the stability of the osteotomy gap, promote bone healing, and avoid loss of correction. There are some treatment options for the osteotomy gap site, such as, without bone, autologous bone graft, allogeneic bone graft, bone substitute materials graft, and augment factor graft to enhance bone healing. When the osteotomy gap is less than 10 mm, it achieves a good outcome without bone graft. For the obesity, lateral hinge fracture, large osteotomy gap, or correction angle more than 10°, the bone graft should be considered. In cases whose osteotomy gap is nonunion or delayed union, the autologous bone graft is still the gold standard. When the osteotomy gap repaired with the allogeneic bone graft, it is better to choose fragmented cancellous or wedge-shaped cancellous bone, combining with the locking plate technology, also can achieve better bone union. The bone substitute material of calcium-phosphorus is used in the osteotomy gap, which has the characteristics of excellent bone conduction, good biocompatibility, and resorption, combining with the locking plate technology, which can also achieve better bone union in the osteotomy gap. The augment factors enhance the bone healing of the osteotomy gap of OWHTO is still questionable. The bone union of the osteotomy gap is also related to the size of the osteotomy gap and whether the lateral hinge is broken or not.ConclusionNo matter what type of materials for the osteotomy gap, OWHTO can improve the function and relieve pain for knee osteoarthritis. More randomized controlled trials are needed to provide evidence for clinical decision to determine which treatment option is better for the osteotomy gap of OWHTO.
The use of a filling block can improve the initial stability of the fixation plate in the open wedge high tibial osteotomy (OWHTO), and promote bone healing. However, the biomechanical effects of filling block structures and materials on OWHTO remain unclear. OWHTO anatomical filling block model was designed and built. The finite element analysis method was adopted to study the influence of six filling block structure designs and four different materials on the stress of the fixed plate, tibia, screw, and filling block, and the micro-displacement at the wedge gap of the OWHTO fixation system. After the filling block was introduced in the OWHTO, the maximum von Mises stress of the fixation plate was reduced by more than 30%, the maximum von Mises stress of the tibia decreased by more than 15%, and the lateral hinge decreased by 81%. When the filling block was designed to be filled in the posterior position of the wedge gap, the maximum von Mises stress of the fixation system was 97.8 MPa, which was smaller than other filling methods. The minimum micro-displacement of osteotomy space was –2.9 μm, which was larger than that of other filling methods. Compared with titanium alloy and tantalum metal materials, porous hydroxyapatite material could obtain larger micro-displacement in the osteotomy cavity, which is conducive to stimulating bone healing. The results demonstrate that OWHTO with a filling block can better balance the stress distribution of the fixation system, and a better fixation effect can be obtained by using a filling block filled in the posterior position. Porous HA used as the material of the filling block can obtain a better bone healing effect.
Objective
To evaluate the effectiveness of open wedge high tibial osteotomy (OWHTO) in treatment of medial unicompartmental knee osteoarthritis (MUKOA).
Methods
A clinical data of 61 cases with MUKOA who were treated with OWHTO between January 2015 and January 2017 were retrospectively analyzed. There are 14 males and 47 females with an average age of 52.8 years (mean, 44-60 years). The body mass index ranged from 19.1 to 34.7 kg/m2 (mean, 25.3 kg/m2). Twenty-seven cases were left side and 34 cases were right side. The disease duration was 1-9 years (mean, 5.3 years). The MUKOA was rated as stage Ⅱ in 33 cases and stage Ⅲ in 28 cases. Preoperative Hospital for Special Surgery (HSS) score was 56.0±3.7. Walking visual analogue scale (VAS) score was 4.6±1.0.
Results
The operation time was 49-85 minutes (mean, 66.5 minutes). The length of incision was 10-13 cm (mean, 11.0 cm). The total overt blood loss was 80-210 mL (mean, 139.1 mL). The postoperative bed-rest time was 1-10 days (mean, 4.7 days). All patients were followed up 12-24 months (mean, 17.3 months). The bearing area of tibial platform at 3 months after operation was 60.3%-66.8%, with an average of 63.4%. At 3 and 6 months after operation, the HSS score was 79.1±4.2 and 85.3±3.1 respectively, and the VAS score was 1.7±0.7 and 0.6±0.5 respectively, all showing significant differences (P<0.05).
Conclusion
OWHTO is an ideal choice for treating MUKOA with less postoperative complications. The force line could be corrected by OWHTO. However, the preoperative preparations are very important, especially that the open angle should be measured accurately.
ObjectiveTo compare the clinical and radiologic effectiveness in patients with versus without lateral hinge fracture during medial opening-wedge high tibial osteotomy (MOWHTO) to evaluate the effect of lateral hinge fracture on short-term effectiveness.MethodsThe clinical data of 84 patients (97 knees) with medial compartment osteoarthritis who treated with MOWHTO between September 2015 and July 2018 was retrospectively analyzed. There were 10 males (10 knees) and 74 females (87 knees). The age ranged from 45 to 65 years with an average of 57.7 years. Lateral hinge fracture was recognized by the intraoperative fluoroscopy or immediate postoperative X-ray film. Fractures were classified into types Ⅰ, Ⅱ, and Ⅲ according to the Takeuchi classification. The healing of osteotomy was observed by radiographs during follow-up; the femur tibia angle (FTA), medialproximal tibial angle (MPTA), and hip-knee-ankle angle (HKA) were also calculated. The knee joint function was evaluated by Hospital for Special Surgery (HSS) score and knee society score (KSS).ResultsThe incision healed by first intention. All patients were followed up 15-48 months with an average of 24.8 months. No hinge fracture occurred in 78 knees (80.41%, group A), and lateral hinge fractures were observed in 19 knees (19.59%, group B) and were divided into the type Ⅰ (13 knees, 13.40%) and type Ⅲ (6 knees, 6.19%) groups. Type Ⅰ fractures were not additionally treated, type Ⅲ fractures were anatomic reduced fixed with additional lag screws. X-ray film and CT examination showed that all patients had bone healing at 3 months after operation without delayed healing or nonunion. During follow-up, there was no loosening or fracture of internal fixation plates and screws. HKA, FTA, and MPTA of patients in group A and group B (type Ⅰ and Ⅲ) were significantly improved at each time point after operation compared with preoperative values (P<0.05); there was no significant difference between groups at each time point before and after operation (P>0.05). After operation, the pain of knee joint was alleviated and the function of joint was improved. At last follow-up, KSS score and HSS score of groups A and B were significantly improved compared with those before operation (P<0.05), but there was no significant difference between the two groups (P>0.05).ConclusionThe lateral hinge fracture may occur during MOWHTO. As long as the treatment and rehabilitation were guided according to the fracture classification of the hinge, the effectiveness can be similar to those without the hinge fracture.
Objective To investigate the feasibility and effectiveness of high tibial osteotomy (HTO) in treatment of chronic multi-ligament knee injury (MLKI) associated with lower extremity malalignment. Methods A clinical data of 14 patients (14 knees) of chronic MLKI associated with lower extremity malalignment, who were treated with HTO between January 2016 and September 2020, was retrospectively analyzed. There were 10 males and 4 females, with an average age of 30.5 years (range, 22-48 years). The causes of injury included traffic accident in 8 cases, bruising by a heavy object in 3 cases, falling from height in 2 cases, and twisting in 1 case. According to Schenck classification of knee dislocation (KD), there were 4 cases of KD-Ⅰ [2 cases of anterior cruciate ligament (ACL) and posterolateral complex (PLC) injuries and 2 cases of posterior cruciate ligament (PCL) and PLC injuries], 7 cases of KD-Ⅲ (all of ACL, PCL, and PLC injuries), and 3 cases of KD-Ⅳ. The preoperative hip-knee-ankle angle (HKA) was (167.1±4.7)°, and the posterior tibial slope angle (PTSA) was (16.3±2.7)°. The knee joint was severely unstable and the patients could not stand and walk normally. Among them, 5 cases of medial compartment cartilage were severely worn out (3 cases of Kellgren-Lawrence grading Ⅱ, 2 cases of grading Ⅲ) causing pain. After admission, 2 cases of KD-Ⅰ underwent HTO and ligament reconstruction in the first stage, 1 case of KD-Ⅲ and 1 case of KD-Ⅳ underwent HTO in the first stage and ligament reconstruction in the second stage; the remaining 10 patients only underwent HTO. Results All patients were followed up 12-50 months, with an average of 30 months. The incisions healed by first intention after operation, and no complications such as infection and deep vein thrombosis of the lower extremities occurred. At 12 months after operation, knee range of extension was –5°-0° (mean, –1.2°) and range of flexion was 110°-140° (mean, 125.5°). The Lachman test was negative in 11 cases and positive in 3 cases. The posterior drawer test was negative in 9 cases and positive in 5 cases. The 0/30° varus stress test was negative in 10 cases and positive in 4 cases. The 0/30° valgus stress test was negative in 13 cases and positive in 1 case. The visual analogue scale (VAS) score was significantly lower than that before operation (P<0.05), and the International Knee Documentation Committee (IKDC) score, Lysholm score, and Tegner score were all significantly higher than those before operation (P<0.05). The X-ray film reexamination at 12 months after operation showed that the HKA was (178.2±3.8)° and the PTSA was (8.6±2.4)°, which were significantly different from those before operation (P<0.05). All osteotomies achieved bone union, and the healing time was 3-11 months, with an average of 6.8 months. Conclusion For chronic MLKI associated with lower extremity malalignment, HTO can restore normal lower extremity alignment and improve knee joint function, which is a feasible salvage operation.
Objective To explore the prediction of postoperative coronal lower limb alignment by the tibia fibular angle (TFA) and femoral fibular angle (FFA) after osteotomy in medial open-wedge high tibial osteotomy (MOWHTO). Methods A clinical data of 20 patients with medial compartment osteoarthritis, who were treated with MOWHTO between September 2019 and September 2020, was retrospectively analyzed. Among them, there were 9 males and 11 females; the age ranged from 46 to 69 years, with an average of 56.0 years. The body mass index (BMI) was 21.3- 35.7 kg/m2, with an average of 26.7 kg/m2. Osteoarthritis involved 11 cases of left knee and 9 cases of right knee; the disease duration was 2-6 years, with an average of 3.8 years. According to the Kellgren-Lawrence classification, there were 7 cases of grade Ⅰ, 9 cases of grade Ⅱ, and 4 cases of grade Ⅲ. The angle and height for open-wedge was planned preoperatively by osteotomy master software, and the TFA and FFA were measured by software after simulated osteotomy. The intraoperative angle for open-wedge was adjusted according to TFA and FFA after simulated osteotomy.The lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), joint line convergence angle (JLCA), mechanical femorotibial angle (mFTA), weight-bearing line (WBL) ratio, TFA, and FFA were measured before operation and at 2 days after operation. The difference (X) between the intraoperative measurement value and the preoperative plan value of TFA/FFA, and the difference (Y) between the postoperative WBL ratio and the target alignment (62.5%) were calculated, and the correlation between the two indicators was analyzed by Pearson’s test. According to the median BMI of patients (25.81 kg/m2), the patients were allocated into high BMI group (>25.81 kg/m2, n=10) and low BMI group (≤25.81 kg/m2, n=10), and the influencing factors of WBL ratio was analyzed by linear regression. Results There was no significant difference between pre- and post-operation in LDFA and JLCA (P>0.05); while there were significant differences between pre- and post-operation in MPTA, mFTA, and WBL ratio (P<0.05). The TFA was (89.5±4.0)° during operation and (87.7±4.7)° after operation, showing significant difference (t=2.991, P=0.008). There was a positive correlation between the difference (X) between the intraoperative measurement value and the preoperative plan value of TFA and the difference (Y) between the postoperative WBL ratio and the target alignment (r=0.595, P=0.006). The FFA was (86.9±4.3)° during operation and (85.7±4.4)° after operation, showing significant difference (t=1.760, P=0.094). There was a positive correlation between the difference (X) between the intraoperative measurement value and the preoperative plan value of FFA and the difference (Y) between the postoperative WBL ratio and the target alignment (r=0.536, P=0.015). After BMI stratification, X was an influential factor of Y in the low BMI group (P<0.05), but X was not an influential factor of Y in the high BMI group (P>0.05). Conclusion Intraoperative FFA and TFA can predict coronal limb alignment after MOWHTO. FFA and TFA can predict more preciselyfor patients with BMI≤25.81 kg/m2.
ObjectiveTo explore the short-term effectiveness of medial open wedge high tibial osteotomy (OWHTO) combined with posterior slope angle of tibial plateau correction to treat the osteoarthritis of limited flexion knee with varus deformity.MethodsThe data of 18 cases (18 knee) with osteoarthritis of limited flexion knee with varus deformity between January 2014 and July 2016 were analyzed retrospectively. There were 6 males and 12 females with an average age of 54.9 years (range, 48-64 years). There were 8 cases of left knee and 10 cases of right knee. The varus of knee ranged from 7.45 to 15.52° (mean, 10.63°). According to Kellgren-Lawrence grading standard, there were 4 cases of grade Ⅱ and 14 of grade Ⅲ. OWHTO was used to adjust the varus deformity, and the posterior slope angle of tibial plateau was adjusted to solve the limited flexion.ResultsThe thickness of osteotomy was 10-19 mm (mean, 14.91 mm). The operation time was 1.2-2.0 hours (mean, 1.4 hours). All incisions healed by first intension. All patients were followed up 1.0-2.5 years, with an average of 1.5 years. At last follow-up, the range of knee flexion and Lysholm score, Hospital for Special Surgery (HSS) score, and International Knee Documentation Committee (IKDC) score were significantly higher than preoperative ones, showing significant differences (P<0.05). X-ray films showed that the osteotomy healed at 3- 7 months (mean, 3.6 months) after operation. At last follow-up, the limb alignment by the relative position of tibial plateau and the posterior slope angle of tibial plateau were significantly improved, showing significant differences when compared with preoperative ones (P<0.05).ConclusionThe OWHTO combined with posterior slope angle of tibial plateau correction can significantly improve the range of flexion and functional score in short-term.
ObjectiveTo investigate the effectiveness of arthroscopy combined with high tibial osteotomy (HTO) in the treatment of knee medial compartment osteoarthritis and its influence on cartilage injury.MethodsThe clinical data of 57 patients with knee medial compartment osteoarthritis treated with arthroscopy combined with HTO between March 2017 and March 2019 were retrospectively analyzed. There were 27 males and 30 females with an average age of 52.4 years (range, 44-57 years). The disease duration ranged from 3 to 6 years, with an average of 3.6 years. Twenty-one cases were grade Ⅰ and 36 cases were grade Ⅱ according to Kellgren-Lawrence classification. Flexion contracture of knee joint ranged from 0° to 8° with an average of 1.36° and varus deformity ranged from 5° to 10° with an average of 7.60°. Preoperative arthroscopic evaluation showed that there were 11 cases with grade Ⅰ, 42 cases with gradeⅡ, and 4 cases with grade Ⅲ according to the international cartilage repair classification system (ICRS). Lysholm score, American Hospital for Special Surgery (HSS) score, and International Knee Documentation Committee (IKDC) score were used to evaluate knee function before operation, at 3 months, at 1 year after operation, and at last follow-up. Visual analogue scale (VAS) score was used to evaluate pain. The mechanical medial proximal tibial angle (mMPTA) and femoral tibial angle (FTA) were measured before operation and at last follow-up. When the internal fixator was removed, the knee arthroscopy was performed again to explore the cartilage repair condition, and the regeneration level and maturity level were selected for cartilage grading evaluation.ResultsAll patients’ incisions healed by first intention after operation, and no incision infection or skin necrosis occurred. After operation, the knee joint function of the patients was significantly improved, the pain symptoms were relieved, and the force line measurement reached the target set before operation. The VAS score, Lysholm score, HSS score, and IKDC score were significantly improved at 3 months, 1 year after operation, and at last follow-up when compared with those before operation. They were gradually improved with the time and there were significant differences between time points (P<0.05). mMPTA and FTA were significantly improved at last follow-up when compared with those before operation (P<0.05). When the internal fixator was removed, the arthroscopic re-assessment found that the cartilage regeneration was classified into 10 cases of grade Ⅰ and 47 cases of grade Ⅱ; 18 cases of immature cartilage regeneration and 29 cases of mature cartilage regeneration were found in the knee joints of grade Ⅱ cartilage regeneration. There was no significant difference in the cartilage regeneration grade between different ICRS gradings (H=0.176, P=0.916), and the difference in maturity grading was significant (H=10.500, P=0.005).ConclusionArthroscopy combined with HTO for the treatment of knee medial compartment osteoarthritis can effectively improve the symptoms and function of the knee joint, and can promote the regeneration of articular cartilage.
Objective To review the application of three-dimensional (3D) printing patient-specific cutting guides (PSCG) in open-wedge high tibial osteotomy (OWHTO). Methods The domestic and foreign literature about the use of 3D printing PSCG to assist the OWHTO in recent years was reviewed, and the effectiveness of different types of 3D printing PSCG to assist OWHTO was summarized. Results Many scholars design and use different 3D printing PSCGs to confirm the precise positioning of the osteotomy site (the bone surface around the cutting line, the “H” point of the proximal tibia, the internal and external malleolus fixators, etc.) and the correction angle (the pre-drilled holes, the wedge-shaped filling blocks, the angle-guided connecting rod, etc.) during operation, and all of them achieve good effectiveness. ConclusionCompared with conventional OWHTO, 3D printing PSCG assisted OWHTO has many obvious advantages, such as shortening the operation time, and the frequency of fluoroscopy, and being closer to the expected preoperative correction, etc. However, the effectiveness between different 3D printing PSCGs still need to be discussed in the follow-up studies.
