ObjectiveTo summarize the related research results of open wedge high tibial osteotomy (OWHTO) complicated with lateral hinge fracture. MethodsTo review the relevant literature of OWHTO at home and abroad in recent years and summarize and analyse the clinical experience. ResultsThe lateral hinge rupture may occur during the OWHTO, which may lead to the loss of correction angle after operation, delayed healing or non-union of osteotomy and so on. The lateral hinge plays an important role in the stability of the osteotomy. During the operation, the " safe zone” internal osteotomy can be used to protect the bone. Once the lateral hinge breaks, the TomoFix plate can be used to obtain the sufficient stability. For patients with lateral hinge rupture, functional exercise and full weight loading time should be guided by hinge breakage classification. ConclusionThe intact lateral hinge is beneficial to the healing and rehabilitation of OWHTO. The lateral hinge should be paid enough attention by clinicians.
Objective To summarize the biomechanical research progress on different fixation methods in medial opening-wedge high tibial osteotomy (MOWHTO) and provide references for selecting appropriate fixation methods in clinical applications of MOWHTO for treating knee osteoarthritis (KOA). Methods Recent domestic and international literature on the biomechanical studies of MOWHTO fixation methods was reviewed to analyze the characteristics and biomechanical performance of various fixation techniques. Results The medial-specific osteotomy plate system has become the mainstream due to its high stiffness and stability, but issues such as soft tissue irritation and stress shielding remain. The use of filler blocks significantly enhances fixation stability and promotes bone healing when the osteotomy gap is large, reducing axial displacement by 73%-76% and decreasing plate stress by 90%. Auxiliary screws improve axial and torsional stability, particularly in cases with large correction angles, effectively preventing lateral hinge fractures. Alternative fixation methods like external fixators hold unique clinical value by minimizing soft tissue irritation and allowing postoperative adjustment. Conclusion There is currently no unified standard for selecting MOWHTO fixation methods. Clinical decisions should comprehensively consider factors such as bone quality, correction angle, and postoperative rehabilitation needs.
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.
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.
Objective To investigate the accuracy of split three-dimensional (3D) printing patient-specific instrumentation (PSI) in medial open-wedge high tibial osteotomy (MOWHTO) and its effectiveness in treating medial knee osteoarthritis.MethodsClinical data of 14 patients with medial knee osteoarthritis and treated with split 3D printing PSI-assisted MOWHTO between August 2019 and August 2020 were retrospectively analyzed. There were 5 males and 9 females with an average age of 61 years (range, 43-68 years). The disease duration ranged from 1 to 16 years, with an average of 4.7 years. Preoperative Kellgren-Lawrence grading of knee osteoarthritis included grade Ⅰ in 2 cases, grade Ⅱ in 6 cases, and grade Ⅲ in 6 cases. The Hospital for Special Surgery (HSS) score was 59.1±4.9. The weight bearing line ratio (WBL), hip-knee-ankle angle (HKA), medial proximal tibial angle (MPTA), posterior tibial slope angle (PTSA), and actual correction angle of the lower limbs were measured on postoperative imaging data, and compared with the preoperative measurements and the designed target values to evaluate the accuracy of the PSI-assisted surgery. The patients’ knee function were evaluated with the HSS score at 3 and 6 months postoperatively, and at last follow-up.ResultsOne patient suffered from an incision exudation at 2 weeks postoperatively, and the incision healed after symptomatic treatment. The incisions of other patients healed by first intention. All patients were followed up 7-19 months (mean, 14.8 months). There was no neural injuries, hinge fracture, plate or screw fractures, loosening, or other complications. The WBL was maintained at the postoperative level according to the X-ray examination during the follow-up period. The WBL, HKA, MPTA, and PTSA were all within a satisfactory range after operation. The WBL, HKA, and MPTA were significantly improved when compared with the preoperative measurements (P<0.05). There was no significant difference between preoperative and postoperative PTSA (P>0.05). The differences in postoperative WBL, HKA, MPTA, and correction angle compared with the preoperative designed target values were not significant (P>0.05). The HSS scores were 69.2±4.7, 77.7±4.3, and 88.1±5.4 at 3 and 6 months postoperatively, and last follow-up, respectively. The differences between time points were significant (P<0.05).ConclusionFor patients with medial knee osteoarthritis, the split 3D printing PSI can assist the surgeon in MOWHTO with accurate osteotomy orthopedics and achieve favorable effectiveness.
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.
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.
ObjectiveTo summarize the clinical application and research status of open wedge high tibial osteotomy (OWHTO).MethodsRelevant literature at home and abroad was reviewed, and the clinical application, effectiveness and complications, technical comparison, and surgical skills of OWHTO were summarized and analyzed.ResultsOWHTO is an effective treatment for mild to moderate medial compartment osteoarthritis due to knee varus. This method can delay the injury process of medial compartment of the knee, delay the time of total knee arthroplasty, and even avoid joint replacement surgery by adjusting the axial alignment of the lower extremity to the non-pathological lateral compartment through osteotomy and orthopedic. OWHTO has the advantages of small incision, dynamic adjustment of the axial alignment of the lower extremity, accurate correction of malformation, and rapid postoperative recovery.ConclusionWith the development of surgical instruments and techniques, OWHTO once again enter the sight of orthopedic surgeons. This technique can solve the pain symptoms of arthritis, correct the tibial varus deformity and reconstruct the axial alignment of the lower extremity, and satisfactory clinical results has been obtained.
ObjectiveTo study the results of high tibia osteotomy (HTO) combined with posterior cruciate ligament (PCL) reconstruction for osteoarthritis (OA) of the medial compartment with PCL injury. MethodsBetween March 2008 and June 2014, 11 patients with OA of the medial compartment and PCL injury underwent HTO combined with PCL reconstruction. There were 5 males and 6 females, aged 43-55 years (mean, 50.3 years). All patients had a trauma history, and the duration of injury was 3-5 years (mean, 3.7 years). At preoperation, Hospital for special surgery (HSS) score was 54.73±8.60, Lysholm score was 56.91±4.51, KT-1000 test was (5.71±1.13) mm, and knee range of motion (ROM) was (125.21±4.77)°. The preoperative femoral tibia angle (FTA) and posterior slope angle (PSA) of the tibia plateau were (184.82±2.40)° and (7.18±1.17)° on the X-ray film. ResultsIncisional fat liquefaction occurred in 1 case, and wound healed after dressing change; primary healing of wound was obtained in the other cases. All 11 cases were followed up 12-28 months (mean, 17 months). Bone union was observed at osteotomy site within 6 months, without delayed union or nonunion. After operation, genu varus deformity was corrected with different degrees; the stability of knees was improved in all patients; and the pain of medial knee was released significantly. At 12 months after operation, the FTA was significantly reduced to (176.64±1.96)°; at last follow-up, the HSS score was significantly increased to 88.27±4.76, KT- 1000 test was significantly reduced to (3.18±0.87) mm, and Lyholm score was significantly increased to 86.45±2.34, all showing significant differences when compared with preoperative ones (P<0.05). At last follow-up, the knee ROM was (124.63±2.98)° and the PSA was (7.91±1.30)°, showing no significant difference when compared with preoperative ones (P>0.05). ConclusionThe PSA will not be changed when a combination of HTO and PCL reconstruction is used to treat OA of the medial compartment with PCL injury if the right osteotomy site and reasonable bone graft are selected. The short-term effectiveness is good because of good recovery of the lower extremity force line and knee stability, but the long-term effectiveness remains to be further followed up.
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.