Varus inclination of the distal femur and high tibial osteotomy

Changes in joint space width over time and risk factors for deterioration of joint space width after medial opening-wedge high tibial osteotomy

PURPOSE

The purpose of this study was to evaluate the changes in joint space width (JSW) over time after medial opening-wedge high tibial osteotomy (MOWHTO) and identify risk factors for deterioration of JSW using anteroposterior (AP) and Rosenberg views.

METHODS

We retrospectively analyzed changes in JSW of 104 MOWHTO patients whose preoperative osteoarthritis (OA) grade was K-L grade 3 or less on AP and Rosenberg views. Serial changes in JSW were assessed from preoperatively to at least 3 years postoperatively. Patients were divided into two groups according to JSW change patterns on each of AP and Rosenberg views: non-deterioration group had either unchanged or increased JSW, and deterioration group had decreased JSW. Clinical outcomes were compared using Western Ontario and McMaster Universities OA Index (WOMAC) score between groups. Multivariate logistic regression analysis was performed to identify risk factors for deterioration of JSW.

RESULTS

JSW on average for all patients increased 0.5 mm and 0.8 mm on AP and Rosenberg views, respectively (p < 0.05). Non-deterioration group showed significant improvement based on patient-reported outcomes (WOMAC) than deterioration group (all p < 0.05). Undercorrection was an independent risk factor for failure to achieve maintained or increased JSW on both AP (OR 6.885, 95% CI 1.976-23.986, p = 0.002) and Rosenberg (OR 12.756, 95% CI 2.952-55.129, p = 0.001) views.

CONCLUSION

JSW increased gradually and continuously on standing AP and Rosenberg views until postoperative 3 years after MOWHTO. Deterioration of JSW following MOWHTO was closely related to the undercorrection and affected clinical outcomes.

LEVEL OF EVIDENCE

Level III, case control study.

Progress in the treatment of knee osteoarthritis with high tibial osteotomy: a systematic review

BACKGROUND

High tibial osteotomy (HTO) has been used for over 60 years in clinical practice and mainly comprises two major techniques: closed wedge high tibial osteotomy (CWHTO) and open wedge high tibial osteotomy (OWHTO). However, these have been gradually replaced by total knee arthroplasty (TKA), due to inconsistent clinical results and many complications. With the concept of knee-protection and ladder treatment of osteoarthritis, as an effective minimally invasive treatment for knee osteoarthritis, HTO has once again received attention.

METHODS

A systematic literature search was conducted in PubMed, Embase, ClinicalKey, CNKI, and the China Wanfang database. The search terms relating to osteoarthritis and high tibial osteotomy were used. Studies were considered eligible if the participants were adults with knee osteoarthritis (KOA) who had undergone HTO. A total of two reviewers participated in the selection of the studies. Reviewer 1 was assigned to screen titles and abstracts, and reviewer 2 to screen full-text data. Data extraction was completed by reviewer 2, and 30% were checked by the research team. Potential conflicts were resolved through discussion. The methodological quality was assessed using a risk of bias, based on the Cochrane handbook and Newcastle-Ottawa assessment scale. The outcome indicators are (1) posterior slope of tibial plateau, (2) the height of the patella, (3) fracture in the osteotomy plane, (4) survival rate, (5) special surgery knee score (HSS), and (6) the recurrence of varus deformity of the included studies were evaluated according to the guidelines of the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) working group (Atkins et al., BMJ 328:1490, 2004).

RESULTS

Among the 18 articles included, 10 were prospective cohort studies, five were randomized controlled trial (RCT) studies, one was prospective comparative study (PCS), one was retrospective comparative study (RCS), and one was retrospective cohort. The earliest publication year was 1999, and the most recent was 2018. A total of 6555 eligible cases were included, comprised of 3351 OWHTO patients and 3204 CWHTO patients. Five RCT were assessed using risk of bias, based on the Cochrane handbook. Eleven cohort studies and two case-control studies were assessed using the Newcastle-Ottawa assessment scale. These six outcome indicators for a total of twenty-four evidence individuals were evaluated separately, among which the GRADE classification of 1, 2, and 6 was medium quality, and 3, 4, and 5 were low quality. Based on our systematic review, regardless of whether the chosen procedure was OWHTO or CWHTO, both HSS scores increased significantly as compared with the preoperative scores. Compared with CWHTO, the height of the patella and tibial posterior slope angle increased following OWHTO. Additionally, OWHTO has a better long-term survival rate and lower fracture rate, supporting OWHTO as the first treatment choice.

CONCLUSIONS

For young patients with knee osteoarthritis (KOA), high tibial osteotomy (HTO) can be considered as a treatment option to replace total knee arthroplasty (TKA) to reduce the economic burden and promote the reasonable allocation of medical resources. This study shows that compared with CWHTO, OWHTO has certain advantages in long-term survival rate and lower fracture rate, but the level of evidence is lower. In the future, we will need larger sample sizes and longer follow-up randomized controlled trials to improve our research.

Managing intra-articular deformity in high Tibial osteotomy: a narrative review

The joint line convergence angle (JLCA) has a normal range between 0° to 2°, which increases in magnitude depending on the severity and stage of osteoarthritis in the knee.

The JLCA represents the interaction of the intra-articular deformity arising from the osteoarthritis and the surrounding soft tissue laxity. Therefore, the JLCA has become a vital parameter in analysing the long leg alignment views for corrective planning before osteotomy surgery. Recent studies have considered the influence on how the preoperative JLCA is measured and its influence on achieving accurate postoperative desired correction in high tibial osteotomy surgery.

The JLCA also reflects the influence of soft tissue laxity in a lower limb malalignment and many surgeons encourage it to be taken into account to avoid non physiological correction and/or overcorrection with negatively impacted postoperative patient outcome.

This present review addressed how to obtain an accurate preoperative measurement of the JLCA, its influence on postoperative deformity analysis and how to reduce errors arising from an elevated preoperative JLCA.

We have proposed a formula to help determine the value to subtract from the planned correction in order to avoid an overcorrection when performing a corrective osteotomy.

Level of clinical evidence IV, narrative review.

Tibial and femoral osteotomies in varus deformities - radiological and clinical outcome

BACKGROUND

Varus deformities of the knee are frequently corrected by osteotomies, which should be performed at the level of origin. But in contrast to high tibial osteotomies (HTO), little data exists for distal femoral osteotomies (DFO). This study evaluates radiological and clinical outcomes after valgisation osteotomies in the proximal tibia and distal femur.

METHODS

We used an observational cohort study design and prospectively performed preoperative long standing radiographs (LSR), lateral x-rays and clinical questionnaires (SF-36, Lysholm score, VAS). Postoperative LSR and lateral x-rays were obtained on average 18 months postoperative and postoperative clinical questionnaires at final visit (mean follow up 46 months). A subgroup analysis of the different surgical techniques (oHTO vs. cDFO) was performed, with regards to radiological and clinical outcomes.

RESULTS

Finally 28 osteotomies with medial tibial opening (oHTO) or lateral femoral closing (cDFO) wedge osteotomies in 25 consecutive patients (mean age 40 years) were identified. There were 17 tibal and 11 femoral procedures. All osteotomies were performed at the origin of deformity, which was of different etiology. The average deviation of the final HKA compared to the preoperative planning was 2.4° ± 0.4°. Overall, there was a significant improvement in all clinical scores (SF-36: 61.8 to 79.4, p < 0.001; Lysholm-score: 72.7 to 90.4, p < 0.001; VAS: 3 to 1, p < 0.001). There was no significant correlation between surgical accuracy and outcome scores.

CONCLUSION

Valgisation osteotomies lead to a significant improvement in all clinical scores with the demonstrated treatment protocol. An appreciable proportion of varus deformities are of femoral origin. Since cDFO provides comparable radiological and clinical results as oHTO, this is an important treatment option for varus deformities of femoral origin.

Physiologic knee joint alignment and orientation can be restored by the minimally invasive double level osteotomy for osteoarthritic knees with severe varus deformity

PURPOSE

The purpose of this study was to examine early radiological and clinical outcomes following minimally invasive double level osteotomy (DLO) procedure performed for osteoarthritic knees with severe varus deformity.

METHODS

Twenty consecutive patients who underwent DLO for varus osteoarthritic knees were included in the study. All patients could be tracked for a minimum of 1 year. Periodical radiological and clinical evaluations were performed at 6 and 12 months after surgery. In the radiological assessment, the following parameters were measured on full-length weight-bearing radiographs both pre- and postoperatively: mechanical tibiofemoral angle (mTFA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), and joint-line convergence angle (JLCA). In addition, subjective clinical results were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee (IKDC) Subjective Score.

RESULTS

The mean age of the study population was 62.5 ± 6.8 years (range 45-76 years). In the radiological evaluation, the preoperative mTFA, mLDFA, mMPTA, and JLCA values averaged 13.5° ± 3.1° varus, 91.1° ± 1.4°, 82.3° ± 2.0°, and 5.8° ± 2.3°, respectively. At 6 and 12 months, all of the radiological parameters significantly improved and corrected to the values within normal range. In the clinical assessments at the follow-up evaluations, both the KOOS and IKDC subjective scores significantly improved from the preoperative values. No significant changes were noted between the 6 and 12-month results in the radiological and clinical assessments.

CONCLUSIONS

The minimally invasive DLO technique is a valuable surgical technique accomplishing restoration of physiologic knee joint alignment and orientation with significant improvement in patient-registered clinical outcomes in early postoperative evaluation. Although the follow-up period is still short, the excellent clinical and radiological outcomes shown in the present study support the efficacy of this procedure.

LEVEL OF EVIDENCE

Retrospective case series, Level IV.

Development and validation of a prediction model for knee joint line orientation after high tibial osteotomy

Background

Maintenance of optimal knee joint line orientation (KJLO) is important after high tibial osteotomy (HTO). No tools, however, are currently available that could predict the value of postoperative KJLO before surgery. First, this study sought to determine the effects of various preoperative anatomical alignment parameters to postoperative KJLO. Based upon these analyses, we aimed to devise an equation that predicts the value of postoperative KJLO.

Methods

A total of 14 radiographic parameters were measured in preoperative and postoperative full-limb standing anteroposterior radiographs on 50 patients who underwent open-wedge HTO. The parameters were analysed using multivariable linear regression to predict KJLO after HTO. External validation of the equation was done with 20 patients who underwent HTO at another institution.

Results

After HTO, KJLO increased from − 0.8° to 2.9° (P < 0.001). Based on the multivariable linear regression analysis, an equation was derived that can estimate postoperative KJLO after HTO; postoperative KJLO(°) = 1.029 + 0.560 × preoperative KJLO(°) + 0.310 × preoperative tibia plateau inclination(°) + 0.463 × aimed correction angle(°). The adjusted coefficients of determination value for this equation was 0.721. The equation also showed good calibration and predictability in external validation with predicted squared correlation coefficient of 0.867.

Conclusions

This study analysed the effects of preoperative anatomical alignment parameters on the postoperative KJLO. An equation which predicts postoperative KJLO with preoperative anatomical alignment factors was devised and validated. This equation would help in selecting optimal patients for HTO and in selecting the optimal target correction angle in HTO.

The medial proximal tibial angle accurately corrects the limb alignment in open-wedge high tibial osteotomy

PURPOSE

The purpose of this study was to detect the pre- and intra-operative influential factors for lower limb alignment correction error in open-wedge high tibial osteotomy (OWHTO).

METHODS

This study involved 69 patients (71 knees) undergoing OWHTO for primary medial osteoarthritis. The weight-bearing line (WBL) ratio, medial proximal tibial angle (MPTA), and joint line convergence angle (JLCA) were measured on radiographs preoperatively and at 1 month after surgery, and the differences between the pre- and postoperative values were calculated. The correction angle during surgery was also investigated. The radiological correction angle was defined as the difference between the pre- and postoperative MPTA. The correction error was defined as the difference between the correction angle during surgery and the radiological correction angle. The ideal correction angle was defined as when the postoperative WBL passed through Fujisawa's point (WBL = 62.5%), and the alignment error was defined as the difference between the postoperative WBL ratio and 62.5. The correlations among the alignment error, the correction error, correction angle during surgery, pre- and postoperative WBL ratio, MPTA, and JLCA and the differences between the pre and postoperative WBL ratio, MPTA, and JLCA were investigated. In addition, the factor most influential on the alignment error was determined.

RESULTS

The preoperative MPTA was the only predictor of the alignment error after OWHTO. The alignment error was positively correlated with the correction error and correction angle during surgery, and negatively correlated with pre- and postoperative WBL ratio, MPTA, and differences between the pre- and postoperative WBL ratio and JLCA.

CONCLUSION

The preoperative MPTA was the only pre- and intra-operative predictor of the alignment error after OWHTO. The larger the correction angle, the greater the alignment error. The MPTA was recommended as an indicator for improving the correction accuracy. Accurate correction based on the MPTA provides good lower limb alignment and better clinical results.

LEVEL OF EVIDENCE

III Case-control study/Retrospective comparative study.

Younger patients with high varus malalignment of the contralateral knee may be candidates for simultaneous bilateral total knee arthroplasty

PURPOSE

Bilateral total knee arthroplasty (TKA) is being performed more frequently. However, a consensus on whether simultaneous or staged procedures should be performed is not available. This study reviewed the clinical course of contralateral knees in patients who underwent unilateral TKA (UTKA) to determine which patients are candidates for simultaneous bilateral TKA (BTKA).

METHODS

One hundred eighty-six patients with osteoarthritis who underwent UTKA at a single hospital between 2006 and 2009 (follow-up mean, 10.1 years) were retrospectively investigated. Age, sex, obesity, contralateral knee pain, Hospital for Special Surgery score, femorotibial angle (FTA), and Kellgren-Lawrence grades at the time of initial surgery were used to evaluate the risk for requiring contralateral TKA. Survival analysis and receiver-operating characteristic (ROC) analysis were performed.

RESULTS

Ninety-one patients (48.9%) underwent contralateral TKA. The FTA of the contralateral knee (CFTA) was an independent related factor (hazard ratio, 1.15; p < 0.001), and the CFTA cut-off value for the next surgery was 183° (area under the curve, 0.85; sensitivity, 80.7%; specificity, 76.2%). The 10-year Kaplan-Meier survival rates for the CFTA < 183° group and the CFTA ≥ 183° group were 79.1% and 27.0%, respectively. In the CFTA ≥ 183° group, age was the predictor of future TKA, and elderly patients tended to not require a second procedure. The age cut-off value for the next surgery was 76 years.

CONCLUSIONS

Varus deformities in the contralateral knee predicted additional contralateral TKA. Patients with CFTA ≥ 183° and aged 75 years or younger are considered reasonable candidates for simultaneous BTKA.

LEVEL OF EVIDENCE

III.

Development of the double level osteotomy in severe varus osteoarthritis showed good outcome by preventing oblique joint line

INTRODUCTION

The purpose of the study was to describe the development of the surgical technique of double level osteotomy in patients with severe varus malalignment and to investigate the clinical and radiological outcome. It was hypothesized that good clinical results without a higher complication rate can be achieved by double level osteotomy to normalize joint angles and avoid joint line obliquity even in cases of progressed osteoarthritis.

MATERIALS AND METHODS

Between 2011 and 2014, 33 patients (37 knees) undergoing double level osteotomies (open wedge HTO and closed wedge DFO) were included; of these, 24 patients (28 knees) were available in mean of 18 ± 10 months for the follow-up examination. Indication was symptomatic varus malalignment and medial compartment osteoarthritis. Postoperatively, these patients were assigned to 20 kg partial weight-bearing using two crutches for 6 weeks followed by full weight-bearing. No braces or casts were used. Full weight-bearing long leg anteroposterior radiographs were obtained preoperatively, after 6 weeks and at the time of final follow-up. Mechanical tibiofemoral angle (mTFA), mechanical lateral distal femoral angle (mLDFA) and medial proximal tibia angle (MPTA) were measured. Clinical outcome was evaluated using Lequesne-, Lysholm-, Oxford-, and IKDC-score at the time of follow-up.

RESULTS

The preoperative mTFA of - 11 ± 3° increased to 0 ± 2° at final follow-up. The difference between mTFA-planning and final follow-up was - 2 ± 3° (p < 0.0006). At final follow-up, MPTA and mLDFA were 89.2 ± 2° and 87 ± 2°, respectively. The Lysholm, Oxford, Lequesne, and IKDC scores were 88 ± 13, 44 ± 3, 2 ± 2, and 77 ± 12, respectively.

CONCLUSIONS

This study showed that double level osteotomy for the patients with severe varus malalignment and medial compartment osteoarthritis normalises the alignment, joint-angles, avoids joint line obliquity, and leads to good clinical results, despite progressive osteoarthritis.

LEVEL OF EVIDENCE

Case series, Level IV.

Large correction in opening wedge high tibial osteotomy with resultant joint-line obliquity induces excessive shear stress on the articular cartilage

PURPOSE

The purpose of this study was to analyse the resultant stress induced by joint-line obliquity after HTO for varus knee deformity using a three-dimensional (3D) finite element model analysis.

METHODS

The geometrical bone data used in this study were derived from commercially available human bone digital anatomy media. The 3D knee models were developed using 3D computer-aided design software. The articular surface was overlaid with a 2-mm-thick cartilage layer for both femoral and tibial condyles. Ligament structures were simulated based on properties reported in previous anatomical studies. Regarding the loading condition, isolated axial loads of 1200 N with lateral joint-line inclinations of 2.5°, 5°, 7.5°, and 10° in reference to the horizontal axis were applied to the femur to simulate the mechanical environment in a knee with joint-line obliquity.

RESULTS

A steep rise of shear stress in the medial compartment was noted in the model with obliquity of 5° or more. This laterally directed shear stress exhibited an incremental increase in accordance with the obliquity angle. The maximum shear stress value in the medial cartilage increased from 1.6 MPa for the normal knee to 3.3, 5.2, and 7.2 MPa in the joint-line obliquity models with 5°, 7.5°, and 10° of obliquity, respectively.

CONCLUSIONS

The effects of HTO for varus knee deformity on the amount/distribution of stresses in the articular cartilage were analysed using a 3D finite element model. It was shown that joint-line obliquity of more than 5° induced excessive shear stress in the tibial articular cartilage. A large amount of correction in OWHTO with a resultant joint-line obliquity of 5° or more may induce detrimental stress to the articular cartilage. Double-level osteotomy should be considered as a surgical option in this situation.

Large meniscus extrusion ratio is a poor prognostic factor of conservative treatment for medial meniscus posterior root tear

PURPOSE

The purpose of this study was to find a prognostic factor of medial meniscus posterior root tear (MMPRT) for surgical decision making.

METHODS

Eighty-eight patients who were diagnosed as acute or subacute MMPRT without severe degeneration of the meniscus were treated conservatively for 3 months. Fifty-seven patients with MMPRT showed good response to conservative treatment (group 1), while the remaining 31 patients who failed to conservative treatment (group 2) received arthroscopic meniscus repair. Their demographic characteristics and radiographic features including hip-knee-ankle angle, joint line convergence angle, Kellgren-Lawrence grade in plain radiographs, meniscus extrusion (ME) ratio (ME-medial femoral condyle ratio, ME-medial tibial plateau ratio, ME-meniscus width ratio), the location of bony edema, and cartilage lesions in MRI were compared. Receiver operating characteristic (ROC) curve analysis was also performed to determine the cut-off values of risk factors.

RESULTS

The degree of ME-medial femoral condyle and medial tibia plateau ratio of group 2 was significantly higher than group 1 (0.08 and 0.07 vs. 0.1 and 0.09, respectively, both p < 0.001). No significant (n.s.) difference in other variables was found between the two groups. On ROC curve analysis, ME-medial femoral condyle ratio was confirmed as the most reliable prognostic factor of conservative treatment for MMPRT (area under ROC = 0.8).

CONCLUSION

The large meniscus extrusion ratio was the most reliable poor prognostic factor of conservative treatment for MMPRT. Therefore, for MMPRT patients with large meniscus extrusion, early surgical repair could be considered as the primary treatment option.

LEVEL OF EVIDENCE

III.

Serial Changes in the Joint Space Width and Joint Line Convergence Angle After Closed-Wedge High Tibial Osteotomy

BACKGROUND

There have been little data concerning serial changes in the joint space width (JSW) and joint line convergence angle over the course of follow-up periods after closed-wedge high tibial osteotomy (CWHTO).

PURPOSE

To evaluate serial changes in the JSW and joint line convergence angle after CWHTO.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 100 computer-assisted CWHTOs with a minimum follow-up period of 3 years (mean, 4.4 years) were analyzed. Clinically, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score was evaluated. Radiographically, the mechanical axis was measured preoperatively and postoperatively. The minimal JSW was measured as the shortest distance between the femur and the tibia. The convergence angle was measured as the angle between the tangent to the subchondral plates of the femoral condyle and the tibial plateau. Serial changes in these measurements were analyzed preoperatively; at 3 months, 6 months, 1 year, and 2 years postoperatively; and at the final follow-up. The intraclass correlation coefficients for all measurements were greater than 0.8.

RESULTS

The mean WOMAC score improved from 41.4 preoperatively to 14.9 at the final follow-up. The preoperative and postoperative mean mechanical axis was 8.1° varus and 1.6° valgus, respectively. The mean minimal JSW was 2.5, 2.9, 2.9, 3.1, 3.2, and 3.1 mm preoperatively and at 3 months, 6 months, 1 year, 2 years, and the final follow-up, respectively ( P < .001). The mean convergence angle was 4.4°, 3.9°, 4.0°, 4.1°, 4.2°, and 4.3°, respectively, during the same time periods ( P = .068).

CONCLUSION

Cartilage healing, as indicated by the JSW, and clinical improvement were maintained over the minimum 3-year follow-up after CWHTO. Cartilage pressure, as indicated by the convergence angle, remained unchanged after CWHTO.

Factors associated with discrepancies between preoperatively planned and postoperative alignments in patients undergoing closed-wedge high tibial osteotomy

BACKGROUND

To evaluate the difference between preoperative plan and postoperative alignment after closed-wedge HTO and determine factors associated with difference.

METHODS

This retrospective cohort study included 165 cases with closed-wedge HTO. The following radiographic parameters were measured: mechanical tibiofemoral angle (mTFA), mechanical medial proximal tibial angle (MPTA), joint line convergence angle, mediolateral joint width discrepancy, Kellgren-Lawrence (K-L) grade, and discrepancy between the correction angle in tibia and correction angle in mTFA. The linear regression analysis was used for the preoperative factors that affect the discrepancy between correction angle in tibia and correction angle in mTFA.

RESULTS

Preoperative and postoperative mTFA was varus 8.3°±3.7 and valgus 3.1°±2.6. The MPTA was varus 6.2°±3.1 preoperatively, valgus 3.7°±3.0 postoperatively. The mediolateral joint width discrepancy was 3.1mm±1.8 preoperatively and 1.8mm±1.4 postoperatively. The discrepancy between correction angle in tibia and correction angle in mTFA was 1.5°±2.3 valgus. By regression analysis, one degree of valgus overcorrection was found to be related with every 2.5° of joint convergence angle (r²=0.396), 2.4mm of mediolateral joint width discrepancy (r²=0.310) and increased one grade of K-L classification (r²=0.107) as preoperative measurement.

CONCLUSIONS

The 1.5° valgus overcorrection of postoperative mTFA was found compared with planned correction angle in tibia. By the equation, every 2.5° of joint convergence angle and 2.4mm of mediolateral joint width discrepancy preoperatively could predict one degree of valgus overcorrection.

Distal femoral valgus osteotomy: bone healing time in single plane and biplanar technique

Varus deformity can be localized in the tibia, in the femur or in both. If varus deformity is localized within the femur, it is mandatory to correct it in the femur. This report presents the technique and results of a consecutive case series of lateral uniplanar and biplanar closed-wedge valgus osteotomy of the distal femur for the treatment of varus deformity of the knee. Retrospectively, fifteen patients (sixteen knees) were identified. Indications for surgery varied from unloading an osteoarthritic medial compartment to reduction to symmetrical varus leg alignment. Pre- and post-operative X-rays, including a full leg radiograph, were assessed as well as bone healing time at follow-up intervals. Clinical outcome was assessed using different questionnaires. There were nine male and six female patients with a median age at surgery of 45 (±14) years. The mLDFA changed from 95.9° (±2.7°) preoperatively to 89.3° (±2.9°) post-operatively. Preoperative planning and the use of angle stable implants resulted in accurate corrections according to preoperative aims in all but one patient. At follow-up (mean, 40 months), the mean VAS score was 2.5 (±2.4) and the WOMAC score averaged 80 (±20). The mean bone healing time of biplanar osteotomies (4 ± 3 months) was shorter than in the uniplanar osteotomies (6 ± 3 months). Distal lateral closed-wedge valgus osteotomy of the femur for the treatment of femoral varus deformities resulted in clinical improvement and accurate corrections in patients with different aims for correction. A biplanar osteotomy technique shortens bone healing time.

Survival and clinical outcome of isolated high tibial osteotomy and combined biological knee reconstruction

PURPOSE

We sought to determine survival and clinical outcomes of high tibial osteotomy (HTO) with or without articular cartilage surgery and/or meniscal allograft transplantation in patients with medial compartment chondral pathology, varus malalignment, and/or meniscal deficiency, whether there is any difference in survival or clinical outcome between these patient cohorts, and whether there is any difference between opening- (OWHTO) and closing-wedge (CWHTO) techniques.

METHODS

A systematic review of multiple medical databases was performed using PRISMA guidelines. Study quality was assessed via modified Coleman Methodology Scores (MCMS).

RESULTS

Sixty-nine studies were included (4557 subjects). MCMS rating was overall poor. Mean follow-up was 7.1 years. Mean subject age was 53 years. Survival of isolated HTO was 92.4%, 84.5%, 77.3%, and 72.3% at 5, 10, 15, and 20 years of follow-up. At 5 years of follow-up, HTO with articular cartilage surgery had significantly greater survival (97.7%) than either isolated HTO (92.4%) or HTO with MAT (90.9%). Isolated HTO, HTO with articular cartilage surgery, and HTO with MAT all significantly improved subjective and objective clinical outcome scores. At two years of follow-up, survival was significantly greater following OWHTO (98.7%) versus CWHTO (96.7%). However, at all other time points with or without combined articular cartilage surgery and/or MAT, there was no significant survival difference between the techniques.

CONCLUSIONS

Survival and clinical outcomes of isolated HTO were excellent at short- and mid-term follow-ups, but deteriorated with time. HTO with concomitant procedures also demonstrated excellent early survival and clinical outcomes that deteriorated with time (up to 10 years).

Gradual bilateral genu varum correction in skeletal dysplasia using the Ilizarov method

BACKGROUND

Options for lower limb realignment in skeletal dysplasia are acute versus gradual correction, internal versus external fixation, and external fixation with or without intramedullary nailing. The safety and versatility of the Ilizarov method in skeletal dysplasia patients makes it a procedure of choice.

MATERIALS AND METHODS

We describe here our experience with this procedure with 48 skeletal dysplasia patients, with a mean age of 15 years, and a minimum follow-up of 2 years. Preoperative, postoperative, and latest follow-up measurements of tibia-femur (T-F) angle, conventional mechanical axis deviation (MAD-C), ground mechanical axis deviation (MAD-G), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), posterior distal femoral angle (PDFA), and posterior proximal tibial angle (PPTA) were compared.

RESULTS

The mean lengthening amount (LA) was 7.4 cm, mean lengthening percentage (LP) was 35.5%, mean external fixation index (EFI) was 28 days/cm, and mean healing index (HI) was 35 days/cm. Mean MAD-C and MAD-G correction were 9.3 mm and 11.8 mm, respectively. T-F angles, PPTA, MAD-C, and MAD-G were significantly improved. Equinus deformity was the most prominent obstacle, and varus recurrence was the most frequent sequela.

CONCLUSION

In most skeletal dysplasia patients, lower limb realignment with gradual deformity correction using the Ilizarov method may be a reliable option. Equinus deformity occurs in those with more than 40% lengthening, but can be easily corrected. In addressing varus recurrence after gradual correction, the intrinsic and extrinsic factors should be sought first then treated accordingly.

Reference axes for reconstruction of the knee

Knee alignment is an essential problem in reconstructive surgeries of the knee. Quite a number of reference parameters have been suggested to help the surgeons to get proper alignment during operations. In this article, most commonly used reference axes, both for the axial and the rotational, are reviewed, in an attempt to highlight their reliabilities and clinical relevance.