Medial Opening Wedge High Tibial Osteotomy Decreases Medial Meniscal Extrusion and Improves Clinical Outcomes and Return to Activity

Editorial Commentary: Medial Meniscal Root Repair Should Be Combined With High Tibial Osteotomy in Cases of Meniscal Extrusion

Medial meniscus extrusion (MME) is classically defined as radial displacement of ≥3 mm outside the tibial border. MME is usually seen in middle-aged patients, and it is strongly associated with medial meniscus root (MMR) pathology and medial femorotibial compartment degenerative change. MMR tears are associated with cartilage defects of the medial femoral condyle (89%) and MME ≥3 mm (67%). If MMR tears are associated with MME, high tibial osteotomy combined with MMR repair may reduce MME and protect the medial compartment. Recent research shows combined MMR repair and high tibial osteotomy yield improved radiographic and functional outcomes.

Around-the-knee osteotomies part II: Surgical indications, techniques and outcomes - State of the art

Recent advances in surgical techniques and planning for knee-based osteotomies have led to improvements in addressing lower extremity malalignment. Part 1 of this review presented the biomechanical and clinical rationale of osteotomies, emphasizing the importance of osteotomies for restoring normal knee kinematics. In Part 2 of this review, indications, surgical technique and outcomes of osteotomies to correct coronal, sagittal and axial plane deformities will be examined. Traditional high tibial and distal femoral osteotomies will be discussed in addition to more recent advanced techniques including biplanar corrections and double-level osteotomies, as well as slope-correcting osteotomies. Patient-specific instrumentation and its use in more complex corrections will also be addressed.

High survivorship and low complication rate in a single-centre series of 651 medial opening wedge high tibial osteotomy cases with a mean follow-up of 13 years

PURPOSE

This study aimed to report the early to midterm results of medial opening wedge high tibial osteotomy (MOWHTO) from the largest single-centre osteotomy database. The primary outcomes were reporting the radiological corrections and the functional outcomes represented by multiple patient-reported outcome measures (PROMs). The secondary outcomes were to report the complications, revisions and survivorship up to 10 years postoperatively.

METHODS

A prospectively maintained single-centre database of 1138 knee osteotomies was retrospectively reviewed. Patients who underwent MOWHTO and met the inclusion criteria were included. Those inclusion criteria were moderate to severe knee pain that failed conservative management; varus knee malalignment; and isolated medial osteoarthritis of the knee. A total of 651 cases, with a mean age of 46.7 ± 9 years and a mean body mass index of 29.6 ± 5.2 kg/m2 , were included. This comprised 71% males (n = 462) and 29% females (n = 189). The mean follow-up was 158.1 ± 45.4 months. Multiple PROMs were recorded preoperatively and serially postoperatively. This included the Knee injury and Osteoarthritis Outcome Scores, the Oxford Knee Score, the Oxford Knee Score-Activity and Participation Questionnaire, the Western Ontario and McMaster University Scores, the Visual Analogue Scale for health and pain, and the EQ-5D, which is a standardised measure of health-related quality of life. All lower limb alignment measurements were recorded pre- and postoperatively. The rates of osteotomy revision, conversion to arthroplasty, complications, and 5- and 10-year survivorship were recorded.

RESULTS

A total of 651 cases were followed up to a mean of 158.1 ± 45.4 months. The mean planned correction angle was 7.6° ± 2.9°. The mean planned opening wedge distance was 8.1 ± 3.1 mm. The mean intraoperative anterior and posterior osteotomy gaps opening were 7.7 ± 3.4 and 8.9 ± 3.8 mm, respectively. Postoperatively, the mean mechanical tibiofemoral angle improved from -5.7° ± 2.9° varus to 1.3° ± 2.5° valgus, the mean medial proximal tibial angle improved from preoperative 85.5° ± 2.3° to postoperative 91.6° ± 2.7° and the mean Mikulicz point improved from 21.7 ± 12.6% to 54.8 ± 11% (all p values < 0.001). All PROMs significantly improved at 24 months follow-up (all p values < 0.001). The rate of osteotomy revision was 1.1% at a mean of 2 ± 2.5 years postoperatively. The overall rate of arthroplasty conversion was 9.1%. This comprised 5.8% total knee arthroplasty conversion at a mean of 6.9 ± 3.5 years postoperatively and 3.2% unicompartmental knee arthroplasty conversion at a mean of 5.7 ± 2.5 years postoperatively. An overall 10.3% complication rate was recorded. The 5 and 10-year survivorship was 97.2% and 91.9%, respectively.

CONCLUSION

MOWHTO is a radiologically and clinically rewarding procedure with a high survival rate at 5 and 10 years and a low complication rate in experienced hands. MOWHTO should be considered in patients presenting with medial unicompartmental knee pain with an evidence of overload and a varus mechanical coronal plane axis.

LEVEL OF EVIDENCE

Level IV, retrospective cohort study.

Effect of limb alignment correction on medial meniscus extrusion under loading condition in high tibial osteotomy

Background

This study aimed to investigate the effect of high tibial osteotomy (HTO) on medial meniscus extrusion (MME) and the association between the changes in limb alignment and MME under weight-bearing (WB) conditions after HTO.

Methods

We included 17 patients with knee osteoarthritis (OA) who underwent HTO. MME was evaluated using ultrasonography in supine and unipedal standing positions. Knee alignment was evaluated radiographically using WB, whole-leg radiographs with the hip-knee-ankle angle (HKAA), percentage of the mechanical axis (%MA), medial proximal tibial angle (MPTA), and joint line convergence angle (JLCA). All measurements were performed serially at four time points: preoperative and 3, 6, and 12 months postoperative. Clinical outcomes were assessed by knee injury and osteoarthrosis outcome score (KOOS) and visual analogue scale (VAS) value for pain.

Results

Mean MME in the WB position was significantly greater than that in the supine position in the preoperative condition; however, MME in both supine and WB positions was significantly lowered postoperatively. The ΔMME, difference of MME between supine and WB positions, was significantly lowered postoperatively and maintained for up to 1 year. MME change in the WB position between preop and postoperative conditions was significantly correlated with change in HKAA and %MA at 1 year postoperative. KOOS and VAS score were significantly improved after HTO.

Conclusions

HTO correcting varus alignment can decrease MME in WB position and minimise the change in MME between supine and WB positions. The changes in MME after HTO were correlated with changes in the mechanical alignments.

Visualization of lateral meniscus extrusion during gait using dynamic ultrasonographic evaluation

PURPOSE

Medial meniscus extrusion is one of the risk factors for knee osteoarthritis (OA). However, lateral meniscus extrusion has not been discussed, and detailed information remains unknown. In particular, the lateral meniscus has high mobility and is expected to be difficult to evaluate in terms of its behavior under static conditions. Dynamic ultrasonographic evaluation was introduced to detect the dynamic behavior of the meniscus during walking. In this study, we aimed to investigate the behavior of the lateral meniscus during walking using dynamic ultrasonographic evaluation.

METHODS

Sixteen participants with knee OA were recruited in this study. The change of lateral meniscus extrusion during walking was recorded using ultrasonography. Medial and lateral meniscal extrusion during the stance phase was measured, and meniscal mobility was defined as the difference in meniscal extrusion between minimum and maximum values (mm), medial meniscal extrusion (∆MME), and lateral meniscal extrusion (∆LME), respectively. The walking cycle and gait forms of lateral thrust were also evaluated using three-dimensional motion analysis systems and analyzed in terms of the correlation with ∆MME and ∆LME.

RESULTS

The lateral meniscus was depicted in the articular plane, and extrusion decreased during the stance phase of the gait cycle. The ∆LME was significantly higher than the ∆MME (p < 0.01). There was a significant positive correlation between ∆LME and lateral thrust (r = 0.62, p < 0.05).

CONCLUSIONS

We found that dynamic ultrasonographic evaluation can be used to visualize lateral meniscus extrusion during walking, and that its behavior is correlated to the degree of lateral thrust.

Evaluation of the bone tunnel position and state of healing on second-look arthroscopy after pullout repair of medial meniscus posterior root tear during open-wedge high tibial osteotomy

BACKGROUND

The aim of the present study was to evaluate the outcome of pullout repair of medial meniscus posterior root tear during open-wedge high tibial osteotomy, including the bone tunnel position and the state of healing on second-look arthroscopy.

METHODS

The cohort comprised 22 patients (six men, 16 women) who underwent arthroscopic root fixation by the transtibial pullout technique for medial meniscus posterior root tear during open-wedge high tibial osteotomy. The mean patient age was 63.7 years. The location of the tibial tunnel was assessed using a percentage-dependent method, and the location of a critical point was determined by two coordinates on CT. We defined the distance between the tibial tunnel center and the medial meniscal posterior root anatomic center as the TC-AC distance. The healing state was classified as complete, partial, or failed on second-look arthroscopy. Patients were categorized into those with complete or partial healing (group H) and those with failed healing (group F). The differences in the outcomes and characteristics of groups H and F were evaluated.

RESULTS

Twelve and 10 knees were classified into groups H and F, respectively. The bone tunnel position was significantly more posterior in group H than in group F. The TC-AC distance was significantly shorter in group H than in group F.

CONCLUSIONS

In pullout repair of medial meniscus posterior root tear during open-wedge high tibial osteotomy, it was considered important to create a bone tunnel position more posterior to increase the healing rate on second-look arthroscopy.

LEVEL OF EVIDENCE

Level Ⅳ.

Dynamic ultrasound reveals the specific behavior of the medial meniscus extrusion in patients with knee osteoarthritis

BACKGROUND

In the dynamic condition, knee osteoarthritis (OA) usually presents with pain. In the weight-bearing condition, a medial meniscus extrusion (MME) may cause severe symptoms and pathological progression. However, the correlation between a dynamic MME and pain has not been elucidated. Now, an MME can be evaluated under dynamic conditions and reflect the characteristics of symptomatic knee OA. This study investigated MMEs during walking and their correlation with knee pain.

METHODS

Thirty-two symptomatic patients with knee OA (mean age, 60.5 ± 9.9 years) were enrolled in this study. The medial meniscus was evaluated using ultrasonograms during walking, and in the static supine and unipedal standing positions, as dynamic and static conditions, respectively. The ΔMME (the difference between the maximum and minimum MMEs) was obtained in each condition. The intensity of the knee pain during walking was measured by the visual analog scale (VAS).

RESULTS

The ΔMME in the dynamic condition was significantly higher than that in the static condition (P < 0.01). There was a significant correlation between VAS and ΔMME only in the dynamic condition.

CONCLUSIONS

The dynamic evaluation is a valid tool for understanding the mechanisms of knee pain and the behavior of the medial meniscus in symptomatic knee OA.

Decrease in medial meniscal extrusion after physical therapy to improve knee pain and range of motion in patients with knee osteoarthritis: A retrospective study

BACKGROUND

Medial meniscal extrusion (MME) is the medial displacement of the meniscus, which extends beyond the tibial margin. Studies have shown an association between MME and knee pain and that surgical treatment can reduce the extent of MME. Here, we describe the beneficial effects of physical therapy as a feasible conservative treatment for MME.

METHODS

Data of 30 patients with knee osteoarthritis who underwent stretching of the semimembranosus tendon and passive range of motion (ROM) exercises twice a week for 8 weeks were retrospectively analyzed. MME was the measured distance between the medial meniscus and the line connecting the medial borders of the femur and tibia using ultrasound. Ultrasound findings of surrounding tissues, including the deep posterior bundle of the medial collateral ligament (dMCL), were recorded. Additionally, knee extension ROM was measured, and inner knee pain when walking was evaluated using a numerical rating scale.

RESULTS

There were significant improvements between the baseline and 8 weeks for MME in the non-weight-bearing position (3.6 ± 0.3 mm vs. 3.0 ± 0.4 mm), MME in the weight-bearing position (4.3 ± 0.4 mm vs. 3.8 ± 0.5 mm), ROM (-12.3° ± 4.1° vs. -3.1° ± 3.8°), and knee pain (7.0 ± 0.9 vs. 1.1 ± 1.4) (each p < 0.001). In almost all cases in which the knee extension ROM improved, the dMCL was bulging at the baseline; after 8 weeks, the dMCL was flattened, suggesting ligament tension on ultrasound imaging.

CONCLUSION

Stretching of the semimembranosus tendon and passive ROM exercises may reduce the extent of MME in patients with knee osteoarthritis. The ultrasound findings suggest that improvement in knee extension ROM may have led to the re-acquisition of MCL tension, which may have influenced MME reduction. Therefore, physical therapy may be a feasible conservative treatment for the reduction of MME.

Knee adduction moment is correlated with the increase in medial meniscus extrusion by dynamic ultrasound in knee osteoarthritis

BACKGROUND

An increase in medial meniscus extrusion (MME) due to abnormal biomechanical stress leads to knee osteoarthritis (OA) progression. MME evaluation during walking is a key method of detecting dynamic changes in the meniscus, and in combination with motion analysis, can provide a deeper understanding of the mechanisms involved in the increase of MME.

OBJECTIVE

To validate the feasibility of MME dynamic evaluation in combination with a motion analysis system based on the correlation between the increase in MME and biomechanical factors.

METHODS

Twenty-three knees from 23 patients with mild to moderate knee OA were analysed in this study. The medial meniscus during walking was evaluated by ultrasound. The increase in MME was calculated as the difference between the minimum and maximum MME during walking. A three-dimensional motion analysis system was synchronised with the ultrasound and then, biomechanical factors such as knee moment and ground reaction force were evaluated.

RESULTS

The wave patterns of the mediolateral and vertical components of ground reaction forces and knee adduction moment were similar to those in the MME based on a high cross-correlation coefficient (>0.8). The increase in MME was significantly correlated with the peak value of the knee adduction moment (r = 0.54, P = 0.0073) but not with the mediolateral and vertical components of the ground reaction force.

CONCLUSION

The findings show that knee adduction moment is correlated with an increase in MME during walking and indicates the validity and feasibility of the dynamic evaluation of MME in combination with a motion analysis system.

Increased medial meniscus extrusion led to worse clinical outcomes after medial opening-wedge high tibial osteotomy

PURPOSE

Given that no studies have assessed the correlation between improvements in medial meniscus extrusion (MME) and clinical outcomes after medial opening-wedge high tibial osteotomy (MOWHTO), the present study aimed to measure the improvement in MME after MOWHTO and to investigate the correlation between the remaining postoperative MME and MOWHTO clinical outcomes by subgroup analysis.

METHODS

This study included 79 patients (80 knees) who underwent MOWHTO with a minimum follow-up of 2 years. MME was measured pre- and postoperatively through magnetic resonance imaging after an average of 19.8 months following MOWHTO surgery. Clinical outcomes were evaluated according to the Knee Injury and Osteoarthritis Outcome Score (KOOS), the Tegner Activity Scale, and the Short-Form 36 questionnaire. In subgroup analysis, postoperative MME was classified into non-pathologic (≤ 3 mm) and pathologic (> 3 mm) groups. The clinical outcomes of the two groups were compared using Mann-Whitney U tests. A regression analysis was performed to determine the preoperative and postoperative characteristics associated with the improvement of MME.

RESULTS

The mean (± standard deviation) values for pre- and postoperative MME were 3.6 (± 1.8) mm and 2.8 (± 1.5) mm, respectively (p < 0.001). In the subgroup analysis of postoperative MME, the non-pathologic group showed better improvement of KOOS than the pathologic group. Preoperative hip-knee-ankle angle was correlated with the improvement of medial meniscal extrusion in both univariate (p = 0.049) and multivariate (p = 0.015) analyses.

CONCLUSION

The MME improved after MOWHTO, and the clinical outcomes were better for patients with a postoperative MME of less than 3 mm than for those with more than 3 mm. MME improvement after MOWHTO was correlated with preoperative varus alignment of the lower extremities.

LEVEL OF EVIDENCE

III (Retrospective cohort study).

Less risk of conversion to total knee arthroplasty without significant clinical and survivorship difference for opening-wedge high tibial osteotomies in varus knee deformities at 10-year minimum follow-up compared to closing-wedge high tibial osteotomies

PURPOSE

The purpose of this study was to evaluate the clinical outcomes and survivorship at minimum 10-year follow-up of patients undergoing primary valgisation high tibial osteotomy (HTO) for medial osteoarthritis (OA), treated by Opening-Wedge HTO (OW-HTO) or Closing-Wedge HTO (CW-HTO).

METHODS

This was a retrospective cohort study of consecutive patients presenting to a single institution undergoing HTO for isolated medial compartment OA. Two hundred and twenty three HTOs for isolated medial tibio-femoral OA were performed between January 2002 and December 2010. Patients were eligible if they had minimum 10-year follow-up and received either a CW or OW-HTO. Fifteen (6.7%) patients died and twenty-five (11.2%) were lost to follow-up. One hundred and eighty three (82.1%) patients were included in the final analysis and divided into two groups: OW-HTO (96/183; 52.4%) and CW-HTO (87/183; 47.6%). Range of motion, KSS, KOOS scores, and conversion to TKA rate were analyzed between groups. Both groups were comparable regarding age, arthrosis stage, gender, ASA score and BMI at the time of HTO. Survival analysis was conducted with re-intervention for TKA as the end point.

RESULTS

At the time of HTO, mean age was 55 years ± 7.9 (27-73.9) with 72.7% of patients being male. The mean follow-up was 13.3 years ± 2.7 (10-19). Sixty-four (34.9%) patients underwent TKA at a mean delay of 9.3 years ± 3 (3-16). The conversion to TKA rate was significantly higher in the CW-HTO group versus the OW-HTO group: 42.5% (37/87) versus 28.1% (27/96) (p = 0.04). The survival at 15-year follow-up was 59.2% in the OW-HTO group versus 54.6% in the CW-HTO group (n.s.). At 13-year follow-up, KSS Function score was significantly better in the OW-HTO (90.9 versus 82.4; p = 0.007). No significant difference was observed between the two groups regarding the KOOS score, KSS Knee Score and complication rate.

CONCLUSION

At mean follow-up of 13 years, no significant clinical and survivorship difference was observed between the two groups. The conversion to TKA was significantly lower following OW-HTO. Minor correction was associated with risk of requiring subsequent TKA.

LEVEL OF EVIDENCE

Retrospective case series, IV.

Clinical significance and management of meniscal extrusion in different knee pathologies: a comprehensive review of the literature and treatment algorithm

The menisci are crescent-shaped, fibrocartilaginous structures that play a crucial role in the load transition and distribution of the contact forces along the tibiofemoral articulation. Meniscal extrusion (ME) is a radiological finding, especially in magnetic resonance imaging (MRI) scans, for which there has been growing interest in recent years. ME, in the coronary plane, is defined as the maximum distance of the most distal end of the meniscus from the border of the tibial plateau, where the tibial eminences are the most prominent, without taking into account the osteophytes. Although there is still controversy in the literature in respect of the optimal cutoff value, a threshold of 3 mm is considered significant. ME has no specific clinical finding or sign and it is encountered in many knee pathologies. It is associated with either rapidly progressive knee osteoarthritis or early onset of knee osteoarthritis and increased morbidity. In this review, we delineate the clinical significance of ME in various knee pathologies, as well as when, why and how it should be managed. To the best of our knowledge, this is the first study to elaborate on these topics.

Degenerative Meniscus in Knee Osteoarthritis: From Pathology to Treatment

Knee osteoarthritis is a common degenerative joint disease characterized by chronic knee pain and disability in daily living. The lesion can involve the cartilage as well as the synovium, bone, ligaments, and meniscus, indicating a complicated pathology for knee osteoarthritis. The association with the meniscus has recently attracted much attention. Meniscal tears can initiate and progress knee osteoarthritis, with deleterious effects on the important roles of the meniscus in load distribution, shock absorption, and stability of the knee joint. Degenerative meniscus lesions are commonly observed in elderly people, but they have less impact on the prognosis of osteoarthritis. However, they are often accompanied by meniscal extrusion, which substantially decreases the hoop function of the meniscus and increases the risk of knee osteoarthritis. When surgical treatment is necessary, meniscal tears should be repaired to the greatest extent possible to preserve meniscus function. Long-term studies show better clinical outcomes and less degenerative osteoarthritis changes following meniscal repair than following partial meniscectomy. For meniscal extrusion repair, centralization techniques have been proposed that involve suturing the meniscus-capsule complex to the edge of the tibial plateau. Advancements in orthobiologics, such as platelet-rich plasma or stem cell therapy, have the potential to prevent the initiation or progression of osteoarthritis.

Extent of Preoperative Medial Meniscal Extrusion Influences Intermediate-Term Outcomes After Medial Opening-Wedge High Tibial Osteotomy

BACKGROUND

The purpose of the present study was to determine the relationship between preoperative medial meniscal extrusion, as classified according to magnetic resonance imaging (MRI), and medial opening-wedge high tibial osteotomy outcomes at intermediate-term follow-up.

METHODS

We reviewed the records for 212 patients who had undergone medial opening-wedge high tibial osteotomy for the treatment of medial compartment osteoarthritis between January 2009 and September 2014, with a minimum duration of follow-up of 5 years. Patients were divided into 2 groups according to the presence of pathologic medial meniscal extrusion (>3 mm). Moreover, patients were divided into 4 groups according to MRI Osteoarthritis Knee Score (MOAKS) criteria and relative medial meniscal extrusion values. Associations between the extent of preoperative medial meniscal extrusion and clinical outcomes over a mean duration of follow-up of 8.1 years were evaluated with use of Spearman rank correlation analysis. Regression analyses were performed to determine preoperative characteristics relevant to medial meniscal extrusion. Clinical outcomes were assessed with use of the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Tegner activity scale score.

RESULTS

Postoperative KOOS pain scores were significantly different in the pathologic and non-pathologic medial meniscal extrusion groups (69.9 ± 18.0 versus 79.2 ± 11.4, respectively; p < 0.001). Additionally, the degree of preoperative medial meniscal extrusion based on both classification methods and the postoperative KOOS pain score were significantly correlated (r = -0.404 and -0.364; p < 0.001). Despite the inferior clinical outcomes associated with greater preoperative medial meniscal extrusion, medial opening-wedge high tibial osteotomy was associated with significant improvement in all outcome measures between the preoperative and latest follow-up assessments (p < 0.001). Preoperative meniscal patterns, including horizontal flap, complex, and root tears (p = 0.001), and increased Kellgren-Lawrence grade (p < 0.001) were related to the severity of medial meniscal extrusion. The survival rate was 94.8% at a mean of 8.1 years, and survival was not associated with the grade of medial meniscal extrusion as assessed with either classification scheme.

CONCLUSIONS

At intermediate-term follow-up, greater preoperative medial meniscal extrusion was related to inferior postoperative clinical outcomes, specifically pain, after medial opening-wedge high tibial osteotomy. Despite the inferior results associated with preoperative medial meniscal extrusion, medial opening-wedge high tibial osteotomy was associated with a satisfactory survival rate after a mean of 8.1 years, regardless of the extent of medial meniscal extrusion.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Meniscal Extrusion: A Narrative Review

Background:

Meniscal extrusion, referred to as an external displacement of the meniscus, is a commonly encountered but often overlooked magnetic resonance imaging finding in the knee joint. Meniscal extrusion alters the biomechanical properties of the meniscus, leading to accelerated cartilage degeneration and early osteoarthritic changes. The literature contains discrepancies about meniscal extrusion on topics ranging from definition to diagnosis. This narrative review outlines the pathogenesis, natural history, diagnosis, and treatment of meniscal extrusion.

Purpose:

To review the current literature on meniscal extrusion, from pathogenesis to treatment, and to provide recommendations for future research.

Study Design:

Narrative review.

Methods:

A computer-based search of the PubMed, Ovid Medline, and Cochrane Library databases was used to perform a comprehensive literature review on meniscal extrusion. A total of 81 studies was ultimately included in the review.

Results:

The literature review highlighted the current ambiguity in definition, difficulty in clinical diagnosis, and low level of awareness of this condition. This review covers all aspects related to meniscal extrusion and identifies many of its lesser known aspects.

Conclusion:

In the current literature, meniscal extrusion remains a lesser known albeit common condition because of its relatively silent nature along with lack of knowledge among orthopaedic surgeons. Further studies are warranted to provide better understanding and management of this condition.

Association between medial meniscus extrusion under weight-bearing conditions and pain in early-stage knee osteoarthritis

PURPOSE

This study aimed to investigate the association between the severity of medial meniscus extrusion (MME) under weight bearing and pain in patients with early-stage knee osteoarthritis (OA).

METHODS

Twenty-eight patients with symptomatic early-stage knee OA (Kellgren and Lawrence grade ≤ 2) who visited our outpatient clinic between 2016 and 2018 were included in this cross-sectional study (mean age: 58.0 ± 11.6 years, female: n = 10). MME was evaluated under weight-bearing conditions using ultrasonography. Patients were divided into two groups according to the severity of MME under weight bearing: those with MME ≥ 3 mm were assigned to the severe group, whereas those with MME < 3 mm were assigned to the mild group. The knee injury osteoarthritis outcome score (KOOS) system was used to evaluate knee pain. The incidence of bone marrow lesions (BMLs) was evaluated using magnetic resonance images.

RESULTS

The KOOS pain score was significantly lower in the severe group than in the mild group (P < 0.05). The incidence of BMLs was significantly higher in the severe group (69%) than in the mild group (7%) (P < 0.001).

CONCLUSION

Patients with early-stage knee OA who have greater MME under weight-bearing have more intense knee pain and a higher incidence of BMLs.

The efficacy and safety of tranexamic acid in high tibial osteotomy: a systematic review and meta-analysis

Objective

The present meta-analysis was conducted to evaluate the efficacy and safety of the application of tranexamic acid (TXA) in patients undergoing high tibial osteotomy (HTO).

Methods

PubMed (MEDLINE), EMBASE, and Cochrane Library were systematically searched for relevant literature from inception until 1 February 2021. A combined searching strategy of subject words and random words was adopted. After testing for potential publication bias and/or heterogeneity, we aggregated variables by using the random-effect model. The primary comparison outcome measures were total blood loss, hemoglobin decrease, drain output, wound complications, thrombotic events, and blood transfusion rate of the TXA group versus control. The meta-analysis was performed using the RevMan 5.3 software.

Results

A total of 5 studies were included involving 532 patients. The results showed that there were significant differences in the two groups concerning total blood loss (95% confidence interval [CI] − 332.74 to − 146.46, P < 0.00001), hemoglobin decrease on postoperative day (POD) 1, 2, and 5 (POD 1 95% CI − 1.34 to − 0.63, P < 0.00001; POD 2 95% CI − 1.07 to − 0.68, P < 0.00001; POD 5 95% CI − 1.46 to − 0.84, P < 0.00001), drain output (POD total 95% CI − 195.86 to − 69.41, P < 0.00001) and wound complications (RR = 0.34, 95% CI 0.12 to 0.97, P = 0.04). Nonsignificant differences were found in the incidence of thromboembolic events (RR = 0.46, 95% CI 0.09 to 2.41, P = 0.36) and blood transfusion rate (RR = 0.25, 95% CI 0.03 to 2.27, P = 0.22).

Conclusions

This meta-analysis of the available evidence demonstrated that TXA could reduce total blood loss, hemoglobin decrease, drain output, and wound complications without increasing the incidence of thromboembolic events in patients undergoing HTO. But there is no obvious evidence that TXA could reduce blood transfusion rates. Further studies, including more large-scale and well-designed randomized controlled trials, are warranted to assess the efficacy and safety issues of routine TXA use in HTO patients.

Tranexamic Acid Is Beneficial to Patients Undergoing Open-Wedge High Tibial Osteotomy

The purpose of this study was to investigate the efficacy of tranexamic acid (TXA) in patients undergoing open-wedge high tibial osteotomy (OWHTO). Patients from August 2018 to May 2020 were retrospectively studied. Clinical data were obtained including gender, age, height, weight, body mass index (BMI), smoking, alcohol consumption, hypertension, diabetes, history of aspirin, prepostoperative hematocrit (Hct) and hemoglobin (Hb), thrombotic events, blood transfusion requirement, hospital length of stay, size of osteotomy gap, and wound complications such as wound hematoma and infection. 52 patients were enrolled in the tranexamic acid group (TA group), and 48 patients were enrolled in the nontranexamic acid group (NTA group); there were no significant differences between both groups in terms of gender, age, BMI, preoperative Hb, size of osteotomy gap, incidence of smoking, alcohol consumption, hypertension, diabetes, history of aspirin, thrombotic events, blood transfusion requirement, and wound hematoma and infection. The mean hospital length of stay was 9.4 ± 1.0 days in the TA group and 11.0 ± 1.2 days in the NTA group (P < 0.001), the blood loss was 296.0 ± 128.7 ml in the TA group and 383.3 ± 181.3 ml in the NTA group (P < 0.05), and the postoperative Hb level was 120.8 ± 15.0 g/l in the TA group and 109.5 ± 13.8 g/l in the NTA group (P < 0.001). In conclusion, the administration of TXA is beneficial to patients undergoing OWHTO via decreasing hospital length of stay, reducing blood loss, and maintaining higher postoperative Hb levels.

Preoperative planning by osteotomy master software helps to improve the accuracy of target limb alignment in high tibial osteotomy

Background

The accuracy of targeted lower limb alignment correction following HTO is closely related to patients’ pain relief and knee joint survival time. How to accurately perform osteotomy and how to obtain the ideal target limb alignment to maximize the curative effect are the difficulty in HTO practice. The purpose of this study is to evaluate the predictive and application value of osteotomy master software (OsteoMaster) in coronal plane preoperative planning of high tibial osteotomy.

Method

Sixty-seven patients with medial compartment osteoarthritis and varus deformity treated by medial open-weight high tibial osteotomy were enrolled and divided into observation group (31 cases) and control group (36 cases). The observation group was planned by OsteoMaster, while the control group was planned by Miniaci. The preoperative predicted values of osteotomy depth, open height, correction angle, WBL ratio, and FTA of the observation group were compared with the actual intraoperative values to study their accuracy. The operative time, blood loss, number of fluoroscopy, and WBL ratio were compared between the observation group and the control group to study its application value.

Result

There was no significant difference between two groups in preoperative prediction and intraoperative reality of osteotomy depth, open height, correction angle, FTA, and WBL ratio (P > 0.05). The operation time and number of fluoroscopy in the observation group were significantly less than those in the control group (P < 0.05), while the difference in blood loss was not statistically significant (P > 0.05). The good rate of WBL ratio was 87.1% in the observation group and 75% in the control group.

Conclusion

OsteoMaster has predictive value in osteotomy depth, open height, correction angle, FTA, and WBL ratio of HTO, which is also helpful to reduce the number of fluoroscopy, shorten the operation time, and improve the accuracy of target limb alignment. The drawback of this approach is 2-dimensional approach in contrast to 3-dimensional preoperative planning that is including the more real study.