Closing Wedge High Tibial Osteotomy Research Articles

Correlation between the preoperative Kellgren-Lawrence grade and the clinical outcome of mid-term to long-term follow-up in high tibial osteotomy

Correlation between the preoperative Kellgren-Lawrence grade and the clinical outcome of mid-term to long-term follow-up in high tibial osteotomy

Closing-wedge high tibial osteotomy, a reliable procedure for osteoarthritic varus knee

The purpose of this study was to analyze the long-term clinical and radiological outcomes of patients who underwent closing-wedge High Tibial Osteotomy (HTO) for the treatment of medial compartment osteoarthritis and to evaluate the conversion rate to knee arthroplasty. A retrospective, non-randomized, monocentric study was performed in our Institution considering 166 patients between 1989 and 2012. The final population was composed by 82 patients (94 knees), median age at time of operation was 53 (range 45-73) years. All patients were evaluated clinically (HSS Score, Tegner Scale, VAS and Crosby-Insall Grading) and radiographically (osteoarthritis staging, hip-knee-ankle (HKA) angle, tibial slope and metaphyseal varus). Mean follow-up was 11.9 ± 7.2years. HSS Score increased significantly from 70.8 ± 10 to 93.2 ± 9.1 (p < 0.05) instead Tegner Scale increased from 1.3 ± 0 (range 1-4) to 2.8 ± 0.7 (range 2-6) at the last control (n.s.); VAS score significantly decreased from 7.9 ± 1.4 to 1.6 ± 1.1 (p < 0.05) at last follow-up. According to the Crosby-Insall Grading System, 80 patients (97.4%) reported excellent-good results. HKA angle decreased from 6.9° ± 3.5 to 2.6° ± 2.6 (p < 0.01), tibial slope decreased from 10.1° ± 1.4 to 6.8° ± 2.1 (p < 0.05) and finally the metaphyseal varus decreased from 4.2° ± 0 to 2.1° ± 1.2 (n.s.) at the last follow-up. Adverse events were reported in 4.8%. Osteotomy survivorship rate resulted 92% at 10years, 82% at 15years and 80% at 20years. Sixteen revisions (9.6%) were reported at a mean period of 12.8years. CW-HTO is a valid option for medial osteoarthritis treatment, with successful results in both clinical and radiological outcomes. IV.

The influence of post-operative knee coronal alignment parameters on long-term patient-reported outcomes after closed-wedge high tibial osteotomy

BackgroundBoth intra-articular and extra-articular knee alignment pathologies can affect clinical outcomes after high tibial osteotomy. The purpose of this study was to investigate post-operative knee coronal alignment parameters that affect long-term patient-reported outcomes after closed-wedge high tibial osteotomy (CW-HTO). MethodsThis study included 105 osteoarthritic knees that underwent CW-HTO. Long-term patient-reported outcomes were defined by the 2011 Knee Society Score (KSS) and were collected at an average follow-up of 10.2 years. Post-operative knee coronal alignment parameters, consisting of the femoral tibial angle (FTA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), tibial plateau inclination (TPI), and joint line convergence angle (JLCA), were measured using standing radiographs of the knee at an average follow-up of 11.0 months. The correlations between these parameters and KSS were then assessed by Spearman's correlation analysis. Comparisons of groups classified by MPTA and TPI cutoff values were performed by the Wilcoxon rank-sum test. ResultsPost-operative JLCA showed a significant negative correlation with two KSS sub-scores: satisfaction (R = −0.2232, P = 0.022) and total function (R = −0.2059, P = 0.035). There was no significant difference in any KSS sub-score between the “low” groups (MPTA and TPI less than 95 and 5°, respectively) and the “high” groups (MPTA and TPI greater than 98 and 7°, respectively). ConclusionsAmong knee coronal alignment parameters, a large post-operative residual JLCA, which is an intra-articular varus deformity, was independently associated with worsened long-term clinical outcomes after CW-HTO. Level of evidenceLevel Ⅳ, Retrospective cohort study.

Techniques of High Tibial Osteotomy: A Review

Main intention of the research is to understand about significance of techniques associated with HTO. This research reviewed the techniques of high tibial osteotomy namely high tibial osteotomy, open wedge high tibial osteotomy, closedhigh tibial osteotomy. Patients who are suffering from knee arthritis, high tibial osteotomy assists to prevent or delay the requirement for total or partial replacement of knee to preserve damaged tissue of joint. High tibial osteotomy technique is mainly suitable for active and young patients with knee osteoarthritis. Age plays a main factor in success rate of high tibial osteotomy technique. It could be done in open wedge or closed wedge high tibial osteotomy. For some cases, surgery could be done in combined method (open wedge and closed wedge high tibial osteotomy). When compared with clinical outcomes of closed wedge high tibial osteotomy and open wedge high tibial osteotomy, open wedge high tibial osteotomy performs well in reducing the pain, duration of weight-bearing and return to normal life as soon as possible.

Time to Bone Union after Hybrid Closed-Wedge High Tibial Osteotomy.

Medial open- and lateral closed-wedge high tibial osteotomy (hybrid CWHTO) can overcome the limitations of conventional CWHTO and open-wedge HTO (OWHTO) for medial compartmental osteoarthritis (OA) of the knee. Hybrid CWHTO increases stability by using a rigid locking plate and allows early full weight-bearing. However, the literature contains no information about time to bone union after this new procedure. The aim of this study is to evaluate the time to bone union after hybrid CWHTO. We reviewed 44 knees treated with hybrid CWHTO. Patients were able to stand on both legs on the day after surgery and walked with full weight-bearing within 4 weeks of the procedure. The time to achievement of bone union at the osteotomy site was defined as the number of months until bone union was confirmed on radiographic imaging. The mean time to radiographic confirmation of bone union was 4.5±1.5 months after surgery. Eleven knees (25.0%) required 6 months or more. Radiographic analysis and JOA score improved significantly between before and 1 year after surgery (p<0.01). Hybrid CWHTO is a very useful method for treating medial OA, but radiographic bone union requires 4.5 months on average. We must be aware of bone union after hybrid CWHTO.

The influence of computer-assisted surgery experience on the accuracy and precision of the postoperative mechanical axis during computer-assisted lateral closing-wedge high tibial osteotomy

BackgroundThere is debate regarding the influence of a surgeon’s experience with computer-assisted surgery (CAS) on the postoperative mechanical axis (MA) in CAS-high tibial osteotomy. The purpose of the present study was to compare radiographic results between early and late cohorts of a consecutive series of patients to assess the influence of CAS experience on accuracy and precision of the postoperative MA during CAS lateral closing-wedge high tibial osteotomy (LCWHTO).Materials and methodsResults from 140 CAS-LCWHTO operations were retrospectively reviewed. The first 70 cases, performed during the learning curve period for CAS between 2005 and 2009, were considered to be the “early cohort.” The subsequent 70 cases, performed with greater CAS experience after the completion of the learning curve between 2009 and 2014, were considered to be the “late cohort.” The target postoperative MA angle was valgus 3°. Pre- and postoperative MA angles were evaluated by navigation and radiographs. The proportion of postoperative MA inliers (≤ target angle ±3°) was investigated radiographically. The correlation between the navigation and radiographic measurements was analyzed.ResultsThe average postosteotomy MA angle on navigation was 3.4° in both cohorts. The average postoperative MA angle on radiographs was 1.0° in the early cohort and 2.2° in the late cohort (P = 0.003). Radiographically, the proportion of postoperative MA inliers was greater in the late cohort than in the early cohort (early versus late, 71.4% versus 90%; P = 0.011). The pre- and postoperative correlation between navigation and radiographic measurements was also stronger in the late cohort (early versus late; preoperative r = 0.558 versus 0.663; postoperative r = 0.310 versus 0.376).ConclusionsGreater experience with CAS increased the accuracy and precision of postoperative MA alignment as well as the correlation between navigation and radiographic measurements. Caution should be taken during registration procedures to achieve accurate alignment correction in CAS-LCWHTO.

Preoperative soft tissue laxity around knee was associated with less accurate alignment correction after hybrid closed-wedge high tibial osteotomy.

This study aimed to assess the effect of soft tissue correction due to knee joint laxity, which induces alignment error after hybrid closed-wedge high tibial osteotomy (CWHTO). In addition, to verify whether postoperative soft tissue correction can be predicted from preoperative radiographic parameters. A retrospective evaluation of data from patients treated by CWHTO in 2016-2019 was performed. Standing full-length anteroposterior radiograph measurement was performed pre- and post-surgery, and short anteroposterior radiographs of the knee under maximal manual varus and valgus stress were taken preoperatively. The weight-bearing line, hip-knee-ankle angle (HKA), medial proximal tibial angle (MPTA), and joint line convergence angle (JLCA) were measured, in addition to JLCA under varus or valgus conditions. Soft tissue correction was defined as ΔHKA minus ΔMPTA. Multiple regression analysis was performed to evaluate preoperative factors that could influence soft tissue correction. Data from 49 knees were included in the analysis. The mean soft tissue correction was 3.2°, which indicates an over-correction. Multiple regression analysis revealed that JLCA (β = 0.642; p < 0.001) and valgus JLCA (β = - 0.422; p = 0.001) were significantly associated with postoperative soft tissue correction. The final model of the regression formula was described by the following equation: postoperative soft tissue correction = 0.691 × JLCA - 0.411 × valgus JLCA - 0.399. Preoperative values for JLCA and JLCA under valgus stress are associated with soft tissue correction. Surgeons should, therefore, consider these measurements to achieve postoperative limb alignment.

Tibial rotational alignment after opening-wedge and closing-wedge high tibial osteotomy.

ABSTRACTA lot of good outcomes have been reported after opening-wedge high tibial osteotomy (OWHTO) and closing-wedge high tibial osteotomy (CWHTO).The purpose of this study was to examine the rotational alignment after OWHTO and CWHTO performed by the same surgeon in one hospital.The sample included 30 knees from 24 patients. In all cases, the same orthopaedic surgeon performed the osteotomy surgeries using the same method. The tibial external rotation angle (TERA) was measured using the CT images of proximal tibial plateau and distal tibial malleolus from the consecutive axial CT slices of tibia. In this study, two considerations were examined. The first was the change in rotation angle, which was defined by TERA noted before and after the operation. The second was the relationship between the correction angle of the osteotomy and the rotation angle change of the distal tibia. The first was evaluated using the paired-Student’s t-test, while the second was analyzed with Pearson’s correlation coefficient. In the OWHTO group, the mean TERA was 21.4± 7.0° preoperatively and 20.2 ± 8.0° postoperatively, but no significant difference was seen between pre- and post-operation measurements (p = 0.21). Significant TERA increasing (that is, external rotation of the distal tibia) was seen postoperatively in only three knees. In the CWHTO group, the mean TERA was 19.9 ± 10.5° preoperatively and 16.5 ± 9.5° postoperatively, and significant difference was seen between pre- and post-operative TERA (p < 0.05). No significant correlation was seen between the correction angle and the change of the rotation angle in either group (r = 0.40, r = 0.12) .In the OWHTO group, both internal and external rotation of the distal tibia can occur after surgery. In the CWHTO group, the distal tibia rotated internally postoperatively. No significant correlation was seen between the correction angle and the change in the rotation angle in either group

Proximal tibiofibular division in lateral closing wedge high tibial osteotomy does not increase varus instability of the knee

PurposeWhen performing lateral closing wedge high tibial osteotomy (LCWHTO), fibular untethering can be performed with either fibular shaft osteotomy (FSO) or proximal tibiofibular division (TFD). The aim of this study was to compare the degree of varus instability between the two methods after LCWHTO and to analyze the determinants of varus instability. MethodsThis study retrospectively analyzed 108 consecutive patients with medial compartment osteoarthritis who underwent LCWHTO and had >2 years of follow-up. Patients who underwent unilateral LCWHTO without a previous history of ligament injury were included. Forty-five patients who received LCWHTO with TFD and 51 patients who received LCWHTO with FSO were finally analyzed. The mean follow-up duration was 5.3 years in LCWHTO with TFD and 4.1 years in LCWHTO with FSO. The shortest distance between the lateral tibial plateaus and the corresponding most distal subchondral bone surface of the lateral femoral condyle was measured on varus stress radiographs and compared with that on the unaffected contralateral knee. Multivariable logistic regression analyses were conducted to identify predictors of varus instability. ResultsLateral joint space width showed no significant between-group difference. Multivariable logistic regression analysis revealed that the pre-operative hip-knee-ankle angle was positively correlated with the lateral joint space width. The type of fibular untethering procedure was not associated with postoperative varus instability. ConclusionThe degree of pre-operative varus malalignment is associated with postoperative varus instability after LCWHTO. Proximal tibiofibular division is not a variable for postoperative varus instability after LCWHTO. Level of evidenceLevel III, Retrospective comparative study.

Adequate protection rather than knee flexion prevents popliteal vascular injury during high tibial osteotomy: analysis of three-dimensional knee models in relation to knee flexion and osteotomy techniques.

(1) To analyse popliteal artery (PA) movement in a three-dimensional (3D) coordinate system in relation to knee flexion and high tibial osteotomy (HTO) techniques (lateral closed wedge HTO [LCHTO], uniplane medial open wedge HTO [UP-MOHTO], biplane medial open wedge HTO [BP-MOHTO]) and (2) to identify safe zones of the PA in each osteotomy plane. Sixteen knees of patients who underwent magnetic resonance imaging with extension and 90° flexion were used to develop subject-specific 3D knee flexion models. Displacement of the PA during knee flexion was measured along the X- and Y-axis, as was the distance between the posterior tibial cortex and PA parallel to the Y-axis (d-PCA). Frontal plane safety index (FPSI) and maximal axial safe angles (MASA) of osteotomy, which represented safe zones for the osteotomy from the PA injury, were analysed. All measurements were performed along virtual osteotomy planes. Differences among the three osteotomy methods were analysed for each flexion angle using a linear mixed model. The average increments in d-PCA during knee flexion were 1.3 ± 2.3mm in LCHTO (n.s.), 1.4 ± 1.2mm in UP-MOHTO (P < 0.0001), and 1.7 ± 2.0mm in BP-MOHTO (P = 0.015). The mean FPSIs in knee extension were 37.6 ± 5.9%, 46.4 ± 5.8%, and 45.1 ± 8.1% for LCHTO, UP-MOHTO, and BP-MOHTO, respectively. The mean MASA values in knee extension were 45.8° ± 4.4°, 37.3° ± 6.1°, and 38.9° ± 6.5° for LCHTO, UP-MOHTO, and BP-MOHTO, respectively. Although the PA moved posteriorly during knee flexion, the small (1.7mm) increment thereof and inconsistent movements in subjects would not be of clinical relevance to PA safety during HTO. Diagnostic study, Level II.

Medial closing wedge high tibial osteotomy for valgus tibial deformities: good clinical results and survival with a mean 4.5years of follow-up in 113 patients.

A varus-producing medial closing wedge high tibial osteotomy (MCWHTO) is an uncommon procedure. The aim of this retrospective study was to assess the survivorship and prevalence of post-operative subjective knee laxity and satisfaction in a large cohort of patients with a MCWHTO performed without a MCL-reefing procedure. All patients (n = 176) who underwent a MCWHTO in our clinic between 2008 and 2016 were approached to participate. After review of patient charts, questionnaires were sent to willingly patients. Primary outcome was the survivorship of the MCWHTO; secondary outcome was patient-reported instability and satisfaction. One-hundred and thirteen patients participated in the study. The 5-year survival rate of the MCWHTO was almost 80%. A total of 77% of the patients was satisfied with the treatment. With regard to post-operative subjective knee laxity, 26% of the patients experienced instability of the knee post-operation. Instability was significantly correlated with the KOOS domains, the Lysholm score, the IKDC knee function score and the Physical and Mental Health Domains of the SF-36. Medial closing wedge high tibial osteotomy provides good results regarding survivorship and patient satisfaction for patients with a valgus deformity which is located in the proximal tibia. Clinically relevant is that in the surgical technique without MCL-reefplasty instability is significantly correlated with worse patient-reported outcome measures. The addition of a MCL reefing procedure will improve outcome in selected patients. III.

The efficacy and safety of opening-wedge high tibial osteotomy in treating unicompartmental knee osteoarthritis: Protocol for a systematic review and meta-analysis.

Background:High tibial osteotomy (HTO) is an effective surgical technique that can stop or inhibit the progression of unicompartmental knee osteoarthritis (KOA) to avoid or postpone the need for knee arthroplasty in patients. Whether opening-wedge high tibial osteotomy (OWHTO) is superior to closing-wedge high tibial osteotomy (CWHTO) in treating unicompartmental KOA remains controversial.Methods:Databases (Cochrane Library, EMBASE, and PubMed) were searched from their establishment to July 1, 2018 for randomized controlled trials comparing the application of OWHTO to CWHTO in patients with unicompartmental KOA. The methodological quality of each included study was assessed according to the Cochrane Handbook for Systematic Reviews of Interventions guideline. Review Manager 5.3.5 software (Cochrane Collaboration, Oxford, UK) was used to synthesize the final results.Results:The results will provide useful information about the effectiveness and safety of OWHTO in patients with unicompartmental KOA.Conclusion:The findings of the study will be published in a peer-reviewed journal.PROSPERO registration number:CRD4201811805.

Comparison of torsional changes in the tibia following a lateral closed or medial open wedge high tibial osteotomy

ObjectiveThe aim of this study is to evaluate, by computed tomography (CT), whether different torsional changes occur in the tibia following a lateral closed wedge high tibial osteotomy (CWHTO) versus a medial open wedge high tibial osteotomy (OWHTO) procedure. It was hypothesized that the distal fragment of the tibia would show greater internal rotation after CWHTO. MethodsThirty knees from 25 patients who underwent HTO were enrolled. Fifteen knees of 14 patients who underwent CWHTO and 15 knees of 11 patients who received OWHTO were match-paired. CT scans were taken before and three weeks after surgery. Rotational changes in the distal fragment of the tibia were assessed by measuring the tibial torsion angle (TTA). ResultsThe mean TTA in the CWHTO group pre-operatively and postoperatively was +23.9° ± 7.8° and + 18.2° ± 7.0°, respectively. Internal rotation of the distal fragment of the tibia after CWHTO was −5.7 ± 3.3° (P < 0.001). In the OWHTO group, the mean TTA pre-operatively and postoperatively was +27.9° ± 6.9° and + 26.8 ± 7.7°, respectively, with no significant change in torsion observed (P > 0.05). ConclusionsThe distal fragment of the tibia rotated internally after CWHTO but not after OWHTO. Level of evidenceLevel III: case–control study.

Long-term survival is similar between closed-wedge high tibial osteotomy and unicompartmental knee arthroplasty in patients with similar demographics.

Long-term clinical and radiographic results and survival rates were compared between closed-wedge high tibial osteotomy (HTOs) and fixed-bearing unicompartmental knee arthroplasty (UKA) in patients with similar demographics. Sixty HTOs and 50 UKAs completed between 1992 and 1998 were retrospectively reviewed. There were no significant differences in pre-operative demographics. The mean follow-up period was 10.7 ± 5.7years for HTO and 12.0 ± 7.1years for UKA (n.s.). The Knee Society knee and function scores, WOMAC, and range of motion (ROM) were investigated. The mechanical axis and femorotibial angle were evaluated. Kaplan-Meier survival analysis was performed (failure: revision to TKA) and the failure modes were investigated. Most of the clinical and radiographic results were not different at the last follow-up, except ROM; ROM was 135.3° ± 12.3° in HTO and 126.8° ± 13.3° in UKA (p = 0.005). The 5-, 10-, 15-, and 20-year survival rates were 100%, 91.0%, 63.4%, and 48.3% for closed-wedge HTO, respectively, and 90.5%, 87.1%, 70.8%, and 66.4% for UKA (n.s.). The survival rate was higher than that for UKA until 12years post-operatively but was higher in UKAs thereafter, following a remarkable decrease in HTO. The most common failure mode was degenerative osteoarthritic progression of medial compartment in HTO and femoral component loosening in UKA. Long-term survival did not differ significantly between closed-wedge HTO and fixed-bearing UKA in patients with similar pre-operative demographics and knee conditions. The difference in post-operative ROM and failure mode should be considered when selecting a procedure. III.

Hybrid closed wedge high tibial osteotomy improves patellofemoral joint congruity compared with open wedge high tibial osteotomy.

To evaluate clinical outcomes and radiographic changes in patellofemoral (PF) joint congruity between open wedge high tibial osteotomy (OWHTO) and hybrid closed wedge HTO (HCWHTO). From 2011 to 2013, 36 knees in 31 patients who underwent OWHTO and 21 knees in 17 patients who underwent HCWHTO were evaluated in this retrospective study with a minimum 5-year follow-up. Radiological outcomes including hip-knee-ankle angle (HKA), femoral patellar height index (FPHI), preoperative PF osteoarthritis (OA) grade, medial and lateral joint spaces of the PF joint, and congruence angle were measured. Clinical parameters including the Knee injury and Osteoarthritis Outcome Score (KOOS) and the Oxford Knee Score (OKS) were also evaluated. Preoperative and final follow-up values for each procedure were compared in outcome analyses. Mean preoperative HKA and the degree of PF-OA were significantly more severe for patients treated with HCWHTO compared with those treated with OWHTO (p = 0.001, p = 0.0001). Mean postoperative FPHI was significantly decreased with proximalization of the patella in HCWHTO (p = 0.01) but showed no significant change in OWHTO (n.s.). Regarding PF joint congruity after HCWHTO, lateral joint space and congruence angle were significantly improved (p = 0.0001, p = 0.005), while medial joint space was not significantly changed (n.s.). After OWHTO, congruence angle showed no significant difference (n.s.), but medial and lateral joint spaces were significantly decreased (p = 0.0001, p = 0.018). There were no significant differences in KOOS and OKS between the groups (n.s., n.s.). Although degrees of varus knee and PF-OA were more severe in HCWHTO than those in OWHTO, HCWHTO led to improved PF joint congruity, and its mid-term clinical outcomes were equivalent to those of OWHTO. Therefore, in patients with varus knee combined with PF-OA preoperatively, HCWHTO is a more effective treatment than OWHTO. Therapeutic level III.

Closed wedge high tibial osteotomy for osteoarthritis caused by the treatment of distal femoral osteosarcoma; a case report

Closed wedge high tibial osteotomy for osteoarthritis caused by the treatment of distal femoral osteosarcoma; a case report

A case of medial closing wedge high tibial osteotomy for valgus deformity

A case of medial closing wedge high tibial osteotomy for valgus deformity

Medial collateral ligament laxity in valgus knee deformity before and after medial closing wedge high tibial osteotomy measured with instrumented laxity measurements and patient reported outcome

IntroductionMedial closing wedge high tibial osteotomy (CWHTO) for valgus deformity correction was first described by Coventry whom performed an additional reefing of the medial collateral ligament (MCL) to prevent instability postoperative. In our clinic the additional reefing procedure has never been performed and instability has not been reported routinely by patients. Using instrumented laxity testing, pre- and postoperative valgus and varus knee laxity can be measured objectively. We hypothesize that absence of changes in laxity testing and subjective knee stability scores support that no additional reefing procedure is necessary.Materials and methodsIn a prospective cohort study 11 consecutive patients indicated for medial CWHTO were subjected to pre- and postoperative stress X-rays in 30° and 70° of flexion and opening of the joint line was measured in degrees on the radiographs. Patient reported outcome scores were documented with the KOOS, Lysholm, SF36, Oxford Knee Score and a VAS instability scoring tool.ResultsAll patients (7 females) completed the study, mean age was 46 years. Mean preoperative Hip Knee Ankle angle 6.4° valgus was corrected to mean postoperative alignment 0.1° valgus. A significant difference was measured between mean pre- and postoperative 30° valgus laxity (2.8° vs 5.3°, P = 0.005), 30° varus laxity (6.7° vs 3.2°, P = 0.005) and 70° valgus laxity (2.0° vs 4.8°, P = 0.008). Postoperative patient-reported knee instability as measured with the Lysholm questionnaire was significantly improved compared to preoperative instability (P = 0.006). VAS instability improved, but didn’t reach significance (8.0 preoperative and 5.5 postoperative (P = 0.127). Other outcome measures showed improvement as well. No correlations between radiological findings and outcome scores were found.ConclusionA significant increase in postoperative valgus laxity in 30° and 70° of flexion deems reconsidering addition of MCL reefingplasty to the medial CWHTO although patient reported outcome on subjective stability scores fails to report increase of instability in this study population. Instrumented laxity measurements of medial CWHTO patients treated with additional medial reefingplasty should be performed to prove the value of this procedure.

Short-Term Results of Hybrid Closed-Wedge High Tibial Osteotomy: A Case Series with a Minimum 3-Year Follow-up

PurposeHigh tibial valgus osteotomy (HTO) is a well-established surgical procedure for patients with medial compartment osteoarthritis (OA) of the knee. The hybrid closed-wedge HTO (CWHTO) procedure permits extensive correction in patients with severe deformities or patellofemoral joint OA. The aim of this study was to report the short-term results in a consecutive series of patients treated with hybrid CWHTO.Materials and MethodsWe retrospectively evaluated the clinical outcomes and radiographic parameters in 29 consecutive knees that underwent hybrid CWTHO to correct medial compartment OA at an average follow-up of 52.6 months. Clinical outcomes were assessed using the Lysholm score and knee scoring system of the Japanese Orthopedic Association (JOA). The Kellgren-Lawrence grading system and pre- and postoperative mechanical axis (MA), femorotibial angle (FTA), posterior tibial slope, and patella height were assessed.ResultsThe FTA and MA significantly changed from 180.7° to 170.4° and from 22.0° to 60.2°, respectively. No significant differences were observed between the mean pre- and postoperative posterior tibial slope, Insall-Salvati ratio, or Caton-Deschamps index. The postoperative JOA and Lysholm scores significantly improved from 76.7 to 95.8 and from 58.8 to 90.2, respectively.ConclusionsSatisfactory outcomes can be achieved with hybrid CWHTO in patients with medial OA.

Treatment of cartilage defect and malalignment of the knee

A cartilage defect of the knee was frequently combined with varus alignment of the knee and its treatment should be focused on cartilaginous defect as well as malalignment. If malalignment was not adequately corrected, cartilaginous defect treatment alone was not able to be successful or recurrence could be developed. The treatment methods of cartilage defect were microfracture, augmented microfracture, chondrocyte transplantation and stem cell treatment. Each treatment method has its advantage and disadvantages. Correction of malalignment could be done by either open or closed wedge high tibial osteotomy. Appropriate method should be selected according to the situation. During the last 15 years over 500 cases of high tibial osteotomy with repair of cartilage defect were performed. Clinical outcome study showed The medial open wedge high tibial osteotomy provided good survival at mid- to long-term follow-up. The old age, high-grade cartilage injury on medial and lateral compartment, under-correction of postoperative HKA angle appeared to be significant factors associated with the failure after medial open wedge high tibial osteotomy. Comparison analysis study between showed clinical outcomes was improved regardless of whether augmentation was administered or not. However, Augmented microfracture was is more effective for cartilage regeneration than microfracture alone in medial unicompartmental OA.