Is opening-wedge high tibial osteotomy superior to closing-wedge high tibial osteotomy in treatment of unicompartmental osteoarthritis? A meta-analysis of randomized controlled trials

Closing wedge high tibial osteotomy: An old-fashioned technique? Survival, clinical and radiological outcomes of a case series analysis

INTRODUCTION

Closing wedge high tibial osteotomy (CW-HTO) is a surgical option for active patients with medial knee pain and mild-moderate osteoarthritis with varus limb deformity. Despite its good reported results, this technique has been losing popularity. The aim of this study was to analyse the survival rate, clinical functional outcomes and radiological results of CW-HTO.

METHODS

It is a retrospective case series study. Seventy patients with primary knee osteoarthritis, operated on between 2010 and 2020 in a single Spanish tertiary hospital using the CW-HTO technique and with a minimum follow-up of 2 years were analysed.

RESULTS

Survival rate was 87,6% and 75,5% after a follow-up of 5 and 10 years respectively. Functional outcomes were good-to-excellent (KSS 77.7/100 and OKS 35.6/48) and good pain control (VAS 3.9/10) and high satisfaction (7.2/10) were achieved. Limb varus malalignment was significantly corrected (mean postoperative HKA angle 177,6° and MPTA 90,7°). However, 30% of patients presented hypocorrection, which was associated with inferior survival, functionality and satisfaction.

CONCLUSION

CW-HTO technique can be useful for patients with knee osteoarthritis and varus limb. It allows to correct varus malalignment while achieving good-to-excellent functional outcomes, good pain control, high patient satisfaction and acceptable medium-long term survival rate. However, it is associated with a non-negligible risk of hypocorrection or medial hinge disruption.

[Translated article] Closing wedge high tibial osteotomy: An old-fashioned technique? Survival, clinical and radiological outcomes of a case series analysis

INTRODUCTION

Closing wedge high tibial osteotomy (CW-HTO) is a surgical option for active patients with medial knee pain and mild-moderate osteoarthritis with varus limb deformity. Despite its good reported results, this technique has been losing popularity. The aim of this study was to analyse the survival rate, clinical functional outcomes and radiological results of CW-HTO.

METHODS

It is a retrospective case series study. Seventy patients with primary knee osteoarthritis, operated on between 2010 and 2020 in a single Spanish tertiary hospital using the CW-HTO technique and with a minimum follow-up of 2 years were analysed.

RESULTS

Survival rate was 87.6% and 75.5% after a follow-up of 5 and 10 years respectively. Functional outcomes were good-to-excellent (KSS 77.7/100 and OKS 35.6/48) and good pain control (VAS 3.9/10) and high satisfaction (7.2/10) were achieved. Limb varus malalignment was significantly corrected (mean postoperative HKA angle 177.6° and MPTA 90.7°). However, 30% of patients presented hypocorrection, which was associated with inferior survival, functionality and satisfaction.

CONCLUSION

CW-HTO technique can be useful for patients with knee osteoarthritis and varus limb. It allows to correct varus malalignment while achieving good-to-excellent functional outcomes, good pain control, high patient satisfaction and acceptable medium-long term survival rate. However, it is associated with a non-negligible risk of hypocorrection or medial hinge disruption.

Osteotomy for treating knee osteoarthritis from 2012 to 2023: Bibliometric analysis and global trends

BACKGROUND

Numerous surgical interventions are available for the treatment of knee osteoarthritis (KOA). In recent years, knee-preserving surgery, specifically osteotomy, has gained significant attention from patients, particularly those who are young and physically active, as it not only effectively alleviates pain but also preserves bone integrity, thereby allowing for potential future joint replacement. This study aims to comprehensively analyze the global application trends of osteotomy for KOA and identify the current research hotspots.

METHODS

We conducted a literature search encompassing English-language studies on osteotomy for KOA published from 2012 to 2023 in the Web of Science Core Collection (WoSCC) database. Bibliometric analysis tools, including VOSviewer, CiteSpace, and R Studio, were employed to analyze global trends and research hotspots.

RESULTS

We analyzed 1520 eligible publications, comprising 1350 articles and 170 reviews. The number of articles on osteotomy for KOA has exhibited a consistent upward trend over the past decade. The top 3 contributing countries (South Korea, United States, and China) accounted for 45.98% of all published articles. U.S. scholars exhibited high productivity, prominence, and academic impact in this field. Seoul National University published the most papers on the relationship between osteotomy and KOA, while Sungkyunkwan University had the highest average citation rate. Among authors, Yong Seuk Lee from Korea and Steffen Schroeter from Germany had the highest number of publications and average citation values, respectively. Research interests were clustered into 5 categories: "High tibial osteotomy," "Biomechanics of osteotomy," "Osteotomy combined with cartilage repair techniques," "Postoperative prognosis and outcomes," and "Improvement of surgical techniques."

CONCLUSION

Recent years have witnessed notable rapid progress in the research on osteotomy for KOA. The field is poised for continued growth in terms of academic literature. The United States has emerged as a global leader in knee osteotomy research, while Korea demonstrates considerable potential in this domain. Future research hotspots may encompass high tibial osteotomies, osteotomies combined with cartilage repair techniques, and advancements in surgical techniques for KOA.

Economic evaluation of high tibial osteotomy: Closing wedge is more cost-effective than open wedge technique when analysing the KOOS-12 improvement

PURPOSE

The purpose of this study was to compare the cost-effectiveness of two techniques for performing a knee valgus osteotomy: opening wedge high tibial osteotomy (OW-HTO) vs closing wedge high tibial osteotomy (CW-HTO).

METHODS

In this economic evaluation study, a cost-effectiveness analysis from the perspective of the Spanish public healthcare system was performed, comparing OW-HTO with CW-HTO. All patients with medial knee osteoarthritis who underwent one of these procedures between 2018 and 2020 in our institution were included. The cost analysis included operating room, implant, graft and hospital admission costs. Functional outcomes (KOOS-12, Tegner activity scale, pain and satisfaction) and radiological outcomes (hip-knee-ankle angle, medial proximal tibial angle, tibial slope and patellar height) were analysed. The cost-effectiveness ratio was obtained by calculating the cost of improving the minimal clinically important difference (MCID) of KOOS-12 for each procedure. All costs are expressed in 2020 euros.

RESULTS

Fifty-one patients met the inclusion criteria (27 OW-HTO and 24 CW-HTO). Good to excellent functional outcomes, significant pain reduction (>6 points) and high patient satisfaction (>9/10) were observed in both groups. Both techniques yielded excellent radiological outcomes. N.s. differences in functional or radiological outcomes improvements between both procedures were found. However, the OW-HTO group presented a higher total cost than the CW-HTO group (4612.1 ± 765.6€ vs. 1827.1 ± 701.9€; p < 0.001). The cost-effectiveness ratio was 818.1 ± 46.8 €/MCID for the CW-HTO procedure and 2414.3 ± 115.2 €/MCID for the OW-HTO procedure (p = 0.025).

CONCLUSION

The CW-HTO procedure presented a cost-effectiveness ratio almost three times lower than the OW-HTO procedure. Both techniques allowed to achieve of good to excellent functional outcomes, significant pain reduction and high patient satisfaction while correcting the varus limb malalignment and the metaphyseal tibial varus in patients with medial compartment osteoarthritis.

LEVEL OF EVIDENCE

Level III; economic study.

Better clinical outcomes and faster weight bearing after medial opening-wedge high tibial osteotomy using allogeneic than synthetic graft: A secondary analysis of a Francophone Arthroscopy Society Symposium

INTRODUCTION

Although an autogenous graft has the highest rate of bone union to fill the void created in medial opening wedge high tibial osteotomy (MOWHTO), it also has some disadvantages, such as prolonged surgical time, donor site pain and morbidity. Two possible candidates for ideal grafts to replace autogenous grafts are allogeneic and synthetic graft, which are free from donor site pain and morbidity. However, previous reports comparing the clinical results of allogeneic to synthetic graft have been limited and controversial. The purpose of this study is to compare radiological findings and clinical outcomes of using synthetic versus allogenic graft to fill the void created in MOWHTO.

HYPOTHESIS

The present clinical study hypothesized that allogenic graft to fill the void would allow the higher rate of bone union and better clinical outcomes.

MATERIAL AND METHODS

This study compared the clinical and radiological outcomes of 95 patients who received MOWHTO to fill the void with either synthetic or allogenic graft (44 in Syn group, 51 in Allo group). Preoperatively and postoperatively, all patients were clinically evaluated; Return to work, Tegner activity score, and the Western Ontario and Macmaster University scores were reported. Radiographically, osteoarthritis grade and pre- and postoperative parameters were reported, including Hip-knee-ankle angle, mechanical lateral distal femoral angle, medial proximal tibial angle, joint line convergence angle, proximal posterior tibial angle, and limb length discrepancy. Perioperative details and complications were also reported.

RESULTS

Mean follow-up (months) were 24.0±1.3 in Syn group and 26.8±1.2 in Allo group (p=0.13). The postoperative improvement of pain and global WOMAC scores in Allo group were significantly better than in Syn group (ΔPain of WOMAC: Syn group 27.8±4.4, Allo group 49.3±3.8, p value <0.001*) (ΔGlobal score of WOMAC: Syn group 16.7±3.2, Allo group 37.4±4.9, p value=0.002*). The risk of hinge fracture in Syn group was significantly higher than in Allo group (Hinge fracture by Takeuchi grade (0/1/2/3): Syn group 37/3/3/1, Allo group 43/8/0/0, p value=0.04*). The timing of full weight bearing in Allo group was significantly earlier than in Syn group (Weight Bearing (1=FWB, 2=PWB 3wk, 3=PWB 6wk): Syn group 2.7±0.1, Allo group 2.3±0.1, p value=0.01*).

DISCUSSION

The use of allogenic graft to fill the void in MOWHTO does not show superiority in bone union compared to synthetic graft, however it improves pain, function, decreases the risk of hinge fracture and allows faster weight bearing than synthetic graft.

LEVEL OF PROOF

III; Case-control study.

Incidence and risk factors for surgical site infection after medial opening-wedge high tibial osteotomy using a locking T-shape plate

Medial opening-wedge high tibial osteotomy (MOWHTO) is a well-established surgical method for treatment of isolated medial compartment osteoarthritis with varus deformity, but the surgical outcomes may be compromised by surgical site infection (SSI). This study aimed to investigate the incidence and the risk factors for SSI after MOWHTO. This retrospective study included consecutive patients who underwent MOWHTO for isolated medial compartment osteoarthritis with varus deformity in two tertiary referral hospitals from January 2019 and June 2021. Patients who developed SSI within 12 months of surgery were identified by inquiring the medical records for index hospitalisation, notes of after-discharge outpatient visits, or records of readmission for treatment of SSI. Univariate comparisons were performed to detect the differences between SSI and non-SSI groups, and multivariate logistic regression analysis was used to identify the independent risk factors. Six hundred sixteen patients with 708 procedures were included and 30 (4.2%) cases of SSI occurred, with 0.6% rate for deep SSI and 3.6% for superficial. Univariate analyses showed significant difference between groups in terms of morbidity obesity (≥32 kg/m2 ) (20.0% vs 8.9%), comorbid diabetes (26.7% vs 11.1%), active smoking (20.0% vs 6.3%), time from admission to operation (5.2 ± 4.0 vs 4.1 ± 3.0), size of osteotomy ≥12 mm (40.0% vs 20.0%), type of bone grafting and lymphocyte count (2.1 ± 0.5 vs 1.9 ± 0.6). However, in the multivariate analysis, only active smoking (OR, 3.4; 95% CI, 1.4-10.2), size of osteotomy ≥12 mm (OR, 2.8; 95% CI, 1.3-5.9) and allogeneic/artificial vs no bone grafting (OR, 2.4; 95% CI, 1.0-10.8) remained significant. SSI was not uncommon after MOWHTO, but the majority was superficial. The identified three independent factors, including smoking, size of osteotomy ≥12 mm and allogeneic/artificial bone grafting would help risk assessment and stratification, target risk factor modification and clinical surveillance, and inform patient counselling.

Application of a New M-shaped High Tibial Osteotomy Method: A Technical Note

High tibial osteotomy (HTO) is used as an alternative to total knee arthroplasty in young patients with knee osteoarthritis. In the conventional HTO, if the distraction distance is large, the osteotomy section will be significantly separated, forming a large bone defect gap, which may lead to delayed healing or even nonunion. We treated a series of 10 patients with medial knee osteoarthritis by a novel M-shaped high tibial osteotomy. This helped to improve greater contact of cortical sections and rapid healing of the osteotomy break. Over a mean follow-up period of 8.5 months (range, 6.0-12.0 months), all patients achieved bone union. None of the patients showed complications such as nonunion or infection. The novel M-shaped HTO procedure can reduce the probability of delayed union/nonunion and avoid the complications associated with bone grafting. Hence, this technique may be an effective alternative for the HTO.

Unicompartmental knee arthroplasty vs. high tibial osteotomy for medial knee osteoarthritis (UNIKORN): a study protocol of a randomized controlled trial

BACKGROUND

Medial knee osteoarthritis (OA) is a common health problem resulting in knee pain and limiting patients' physical activity. After failed conservative treatment, unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) are possible surgical treatment options for this condition. There is a paucity of high-quality evidence in the literature comparing objective and subjective outcomes of these procedures. Also, there is no common agreement on whether these procedures provide comparable results in late-stage medial knee OA patients.

METHODS

We will perform a prospective randomized controlled trial comparing HTO and UKA in patients with late-stage medial knee OA. 100 patients with isolated medial knee OA (KL III-IV) are assigned to either UKA (n = 50) or HTO (n = 50) procedure in patients 45-65 years of age. Our primary outcome will be KOOS₅ at one year postoperatively. Secondary outcomes include OARSI physical assessment, length of stay, wearable activity watch, radiographs (OA progression according to Kellgren-Lawrence classification), patient-reported outcomes (KOOS subscales, pain visual analog scale [VAS], Lysholm, and Oxford knee scores), and adverse events (conversion to total knee arthroplasty, surgery-related complications, need for revision surgery) outcomes. Our hypothesis is that neither of the interventions is superior as measured with KOOS₅ at 12 months.

ETHICS AND DISSEMINATION

The institutional review board of the Helsinki and Uusimaa Hospital District has approved the protocol. We will disseminate the findings through peer-reviewed publications.

TRIAL REGISTRATION

ClinicalTrials.gov/TooloH NCT05442242. Registered on 7/1/2022.

Comparative Analysis of Unicompartmental Total Knee Arthroplasty and High Tibial Osteotomy: Time to Total Knee Arthroplasty and Other Outcome Measures

Background

There is no consensus on whether unicompartmental arthroplasty (UKA) or high tibial osteotomy (HTO) is superior for unicompartmental arthritis. While there are studies comparing revision and complication rates, none matched a large number of patients undergoing HTO and UKA in the United States and compared these outcomes. We investigated TKA conversion rate and the complications following HTO or UKA.

Methods

This retrospective study queried the PearlDiver database of all patients undergoing UKA and HTO using CPT codes between January 2011 and January 2020. We compared propensity-matched populations based on age, gender, Charlson comorbidity index, and Elixhauser comorbidity index to compare odds of complications, TKA conversion, and drug use between UKA and HTO groups. Two-independent sample t-test for unequal variances and test of significance were performed.

Results

We found 32,583 UKA patients and 816 HTO patients. Each matched group had 535 patients. One-year complication showed higher risk of pneumonia, hematoma, infection, and mechanical complications among HTO patients. UKA patients used narcotics on average of 10.3 days compared to 9.1 days among HTO patients (P < .01). UKA conversion rates were 4.1%, 5.4%, 7.7%, and 9.2% at 1-, 2-, 5-, and 10-year intervals, respectively. HTO conversion rates were less than 2% at 1- and 2-year intervals, 3.4% at 5-year, and 4.5% at 10-year intervals. This difference was statistically significant at 5- and 10-year intervals (P < .01).

Conclusions

Using large matched cohorts, HTO may be converted to TKA later than UKA in short- to mid-term follow-up, and HTO patients used opioids for shorter duration.

Unicompartmental knee arthroplasty versus high tibial osteotomy for medial knee osteoarthritis: A systematic review and meta-analysis

We aimed to systematically compare the clinical and functional outcomes between unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) for the treatment of medial knee osteoarthritis (KOA). Literatures were searched from PubMed, EMBASE, the Cochrane library, Wanfang DATA, China National Knowledge Infrastructure (CNKI) and SinoMed database until December 2020. Studies comparing postoperative clinical and functional outcomes of UKA versus HTO were included. Totally, 38 studies were included, including 2368 patients with 2393 knees in HTO group and 6536 patients with 6571 knees in UKA group. There was significant difference in postoperative pain, revision rate, complications, and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score between HTO and UKA groups (p < 0.05). No significant difference was found in excellent/good surgical results, Lysholm, Hospital for Special Surgery (HSS) score, Knee Society Knee (KSS) score, knee and function score of Knee Society (KSFS) score and Tegner score between these two groups (p > 0.05). UKA produced less postoperative pain, less complications and superior WOMAC score, whereas HTO offered extended range of motion (ROM) and less revision rate.

A lower starting point for the medial cut increases the posterior slope in opening-wedge high tibial osteotomy: a cadaveric study

PURPOSE

The objective of this study was to evaluate the effects on the posterior tibial slope of different distances from the joint line to start the osteotomy and of varying the placement of the opening wedge in high tibial osteotomy. Starting the osteotomy more distally and an incorrect location for the tibial opening wedge were hypothesized to increase the posterior tibial slope.

METHODS

A cadaveric study was conducted using 12 knees divided into two groups based on the distance from the joint line to the start of the osteotomy: 3 and 4 cm. The preintervention posterior tibial slope was measured radiologically. Once the osteotomy was performed, the medial cortex of the tibia was divided into anteromedial, medial, and posteromedial thirds. A 10° opening wedge was sequentially placed in each third, and the effect on the posterior tibial slope was evaluated radiographically.

RESULTS

Significant changes were observed only in the 3-cm group (p = 0.02) when the wedge was placed in the anteromedial zone. In contrast, in the 4-cm group, significant differences were observed when the opening wedge was placed at both the medial (p = 0.04) and anteromedial (p = 0.012) zones.

CONCLUSION

Correct control of the posterior tibial slope can be achieved by avoiding a low point when beginning the osteotomy and placing the opening wedge in the posteromedial third of the tibia when performing an opening-wedge high tibial osteotomy.

LEVEL OF EVIDENCE

Controlled laboratory study.

Opening- and closing-wedge high tibial osteotomy are comparable and early full weight bearing is safe with angular stable plate fixation: a meta-analysis

PURPOSE

The purpose of this study was to establish the gold standard for surgical technique, fixation, and rehabilitation for HTO in patients with unicompartmental knee osteoarthritis.

METHODS

Medline, Embase, and SPORTDiscus databases were searched up to April 2022. Included were (1) randomized controlled trials (RCTs) comparing opening-wedge HTO (owHTO) and closing-wedge HTO (cwHTO), (2) biomechanical studies and prospective patient studies comparing biomechanical and clinical results for plate fixators, and (3) RCTs comparing an early versus delayed full-weight-bearing (FWB) protocol.

RESULTS

The pooled results for the surgical technique showed no significant differences between owHTO and cwHTO for most PROMs on pain, activity, and risk for conversion to TKA. The cwHTO group showed a slightly better improvement in KOOS/WOMAC pain scores (4.51; 95% CI 1.18-7.85), and a significantly lower change in posterior tibial slope (p = 0.03). The pooled results for the fixation method showed the highest force at maximum failure for the Activmotion (Newclip Technics, France), Aescula (B. Braun Korea, Korea), 2nd generation Puddu (Arthrex Inc., USA), and TomoFix plate (Depuy Synthes, Switzerland). The pooled results for the rehabilitation protocol showed no significant differences between the early full-weight-bearing (FWB) group and the delayed FWB group for functional scores, complication rates, and delayed unions.

CONCLUSION

Both owHTO and cwHTO reduced pain and improved knee function. Locking plate fixation should be used for owHTO. An early FWB protocol has proven to be safe in patients with small corrections, no hinge fractures, and non-smokers.

LEVEL OF EVIDENCE

Level II.

Unicompartmental knee arthroplasty is associated with lower pain levels but inferior range of motion, compared with high tibial osteotomy: a systematic overview of meta-analyses

Background

The purpose of this study was to overview the findings of reported meta-analyses on unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO).

Methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis 2020 (PRISMA 2020) guidelines were followed. Two independent reviewers conducted a literature search of PubMed, Embase, the Web of Science, and the Cochrane Database of Systematic Reviews for meta-analyses comparing UKA and HTO that were published prior to September 2021. Literature screening, data extraction, and article quality appraisal were performed according to the study protocol registered online at PROSPERO (CRD42021279152).

Results

A total of 10 meta-analyses were identified, and different studies reported different results. Five of the seven meta-analyses showed that the proportion of subjects with excellent or good functional results was higher for UKA than for HTO. All three meta-analyses showed that UKA was associated with lower pain levels, and all six of the studies that included an analysis of range of motion (ROM) reported that UKA was inferior to HTO. Four of the eight meta-analyses found that total complication rates were lower for UKA. Only 3 of the 10 meta-analyses found that UKA had lower revision rates. Moreover, in the subgroup analysis, the revision and complication rates of UKA were similar to those of opening-wedge HTO but much lower than those of closing-wedge HTO.

Conclusions

Compared to HTO, UKA was associated with lower pain levels but inferior postoperative ROM. The results were inconclusive regarding whether UKA yielded better knee function scores and lower revision or complication rates than HTO. Accurate identification of indications and appropriate patient selection are essential for treating individuals with OA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03319-7.

Dose tranexamic acid reduce blood loss associated with simultaneous bilateral distal tibial tubercle-high tibial osteotomy?

Background

Simultaneous bilateral distal tibial tubercle high tibial osteotomy (SBDTT-HTO) can result in increased blood loss. The aim of this study is to evaluate the actual hemostatic effect of different tranexamic acid (TXA) treatment regimen in SBDTT-HTO.

Methods

We conducted a retrospective case–control study including 54 patients who underwent SBDTT-HTO. The single-dose group (n = 18) received 1 g of intravenous TXA 15–30 min before surgery, the two-dose group (n = 18) received an additional 1 g of intravenous TXA 6 h after surgery, and the multiple-dose group (n = 18) received an additional 1 g intravenous TXA per-day until discharge. Blood loss, hemoglobin levels, occurrence of any adverse events,functional analysis, quality of life, and pain assessmentswere compared among the three groups.

Results

The total blood loss, hidden blood loss, drainage volumes, and haemoglobin level in the multiple-dose group all occupy a significant advantage.(p < 0.05). In addition, better quality of life were observed in patients belonging to the multiple-dose group then single-dose group.(p < 0.05).

Conclusions

Based on our results, for patients undergoing SBDTT-HTO, sequential intravenous TXA administration can effectively and safely reduce blood loss,maintain postoperative Hb levels,and with the advantage of accelerating recovery.

Good long-term survival and patient-reported outcomes after high tibial osteotomy for medial compartment osteoarthritis

The lateral closing and medial opening wedge high tibial osteotomy can correct a varus malalignment of the knee caused by medial compartment osteoarthritis. These procedures have produced great short-term and mid-term results. As no systematic review has examined their long-term results yet, the goal of this article was to compare the results of all articles about lateral closing and medial opening wedge high tibial osteotomies, published after the year 2000, with a mean follow-up of more than 10 years. A systematic search of the Medline, Web of Science and Cochrane databases resulted in the inclusion of 30 articles. All these studies combined examined the results of 7087 high tibial osteotomies in a total of 6636 patients after a mean follow-up of more than 10 years. Primary outcome measures were the survival rate of the osteotomy, functional scores, patient satisfaction and pain scores. Secondary outcome measures were alignment correction and the identification of factors influencing the survival of the osteotomy. The 5-year, 10-year, 15-year and 20-year survival rates, respectively, ranged from 86 to 100%, 64-97.6%, 44-93.2% and 46-85.1%. The subjective scoring systems showed an improvement postoperatively that was maintained until final follow-up. The anatomical and mechanical tibiofemoral axis were, respectively, corrected to a mean of 7.3°-13.8° of valgus and 0.6°-4° of valgus. The results of the articles evaluating the influence of potential risk factors were contradictory. Despite the low quality of the available evidence, the lateral closing and medial opening wedge high tibial osteotomy seem to remain valid long-term treatment options for patients with painful varus malalignment caused by isolated medial compartment osteoarthritis of the knee. The available results indicate that the need for arthroplasty could be delayed for more than 15 years in the majority of patients. However, higher-quality studies are needed to confirm these findings. As a systematic review is assigned a level of evidence equivalent to the lowest level of evidence used from the analyzed manuscripts, the level of evidence of this systematic review is IV.

No differences in clinical outcomes and cartilage repair between opening wedge and closed wedge high tibial osteotomies at short-term follow-up: A retrospective case series analysis

PURPOSE

The aim of this study was to assess differences in clinical outcomes and postoperative cartilage repair between opening wedge high tibial osteotomy (OWHTO) and closed wedge HTO (CWHTO) for medial osteoarthritis (OA) of the knee.

METHODS

A total of 90 knees of 76 patients who underwent OWHTO (45 knees of 40 patients) and CWHTO (45 knees of 36 patients) was followed-up for 2 years. Cartilage repair at the medial compartment was arthroscopically classified into the following stages: Stage 1 (no reparative change); Stage 2 (partial coverage with white cartilaginous tissue); and Stage 3 (full coverage with white cartilaginous tissue). Clinical outcomes were assessed using Knee Society scores, and radiographic assessment was carried out by anatomical femorotibial angle (aFTA).

RESULTS

Regarding preoperative OA grade, varus alignment, and function score, CWHTO patients showed more advanced OA status than OWHTO patients. Knee scores and function scores were significantly improved after surgery with both HTO procedures (P < 0.05), with no significant difference between the two procedures. Cartilage repair of stage 2 or 3 was found in more than 80% of the subjects in the medial femoral condyle and more than 60% in the medial tibial condyle. However, there were no significant differences between the two HTO procedures. Multivariate logistic regression analysis showed that preoperative International Cartilage Repair Society (ICRS) grade was the only factor affecting cartilage repair.

CONCLUSIONS

CWHTO improved clinical outcomes and cartilage status as much as OWHTO. Although the effects of cartilage repair on clinical outcomes are unknown, HTO is an effective treatment option even for severe medial OA of the knee.

Long-term survival rate of closing wedge high tibial osteotomy with high valgus correction: a 15-year follow-up study

PURPOSE

The influence of closing wedge high tibial osteotomy (CW-HTO) with high valgus correction on its survival is unclear. This study aimed to conduct a 15-year follow-up cohort study to estimate the long-term survival rate of CW-HTO. Factors related to poor outcomes were investigated.

METHODS

A total of 159 knees in 123 patients were followed up, and 120 knees in 96 patients were enrolled for statistical analysis. Femorotibial angles were measured by standing anterior-posterior radiographs of the knee. Clinical objective evaluation was performed by the Japanese orthopaedic association (JOA) score of the knee, and scores lower than 70 points defined the poor result (PR) group. The survival rate of OW-HTO was estimated. Logistic regression analyses were performed to determine the risk factors for PR and conversion to total knee arthroplasty (TKA).

RESULTS

A total of 16 knees in 15 patients (13.3%) underwent TKA 14.0 ± 4.8 (4-20) years after CW-HTO. The 5-year survival rate was 99.2%, 10-year was 96.7%, 15-year was 92.5%, and 86.7% at final follow-up (17.9 years). Based on the JOA score, 44 patients (35.8%) belonged to the PR group, and their risk factors were obesity (p = 0.018), low femorotibial angle (p = 0.019), low JOA score (p = 0.040), low knee extension angle (p = 0.045), and low knee flexion angle (p = 0.046).

CONCLUSIONS

The 15-year survival rate of CW-HTO was 92.5%. While higher scores of objective outcomes were kept over long-term follow-up, the risk factors for a worsening score or TKA conversion were obesity and severity of preoperative knee symptoms.

Comparison of topical and intravenous Tranexamic acid for high tibial osteotomy: A retrospective study

High tibial osteotomy (HTO) is a promising surgery that can treat osteoarthritis of the medial septum of the knee. However, the extensive release of soft tissue and the osteotomy gap may produce intraoperative and postoperative bone bleeding. Tranexamic acid (TXA) is an effective blood management strategy, as it competitively inhibits the activation process of plasminogen and prevents fibrinolytic enzymes from degrading fibrin. Therefore, we compared the operative bone bleeding of patients who underwent HTO who received either intravenous (IV) or topical TXA in this research.The medical records of a total of 191 patients (including 72 who received IV TXA, 64 who received topical TXA and 55 control patients) who received open-wedge HTO were retrospectively reviewed from January 2016 to August 2019. There were no obvious demographic differences between the groups. Here, we used independent parameters to assess the efficacy of topical and IV TXA in reducing blood loss.Compared with the IV TXA group, patients receiving topical TXA therapy had greater blood loss (622 ± 231 ml versus 451 ± 231 ml, mean difference 171 mL [95% CI, 87-254]; p < 0.001). The hemoglobin concentration of the IV TXA group was obviously higher than that of the topical medication group. No patients had thromboembolic complications during the entire study period.In our study, it seemed that either IV or topical use of TXA might reduce blood loss after open-wedge HTO, and the blood loss and amount of drainage in the IV TXA group showed huge decreases compared to those in the topical group.

Effectiveness of High Tibial Osteotomy with or without Other Procedures for Medial Compartment Osteoarthritis of Knee: An Update Meta-Analysis

To improve the long-term outcomes of high tibial osteotomy (HTO) for gonarthritis, many cartilage repair procedures appeared, but their effects were controversial. To evaluate the efficacy of cartilage repair procedures during HTO for gonarthritis, we performed this update meta-analysis. We performed the system retrieval for clinical trials using various databases and then pooled the outcomes of the included studies. Fifteen studies were involved. The pooled results indicated that there were no significant differences in Kellgren and Lawrence (KL) scale (mean difference [MD] = 0.02, 95% confidence interval [CI] = -0.01 to 0.06, p = 0.24), the femorotibial angle (MD = 0.06, 95% CI = -0.04 to 0.16, p = 0.22), and magnetic resonance imaging (MRI) outcomes (MD = 12.53, 95% CI = -2.26 to 27.32, p = 0.10) of patients in experimental group than control. The subgroup analysis showed that the clinical outcomes of abrasion arthroplasty (AA) were worse than control group (standardized mean difference [SMD] -2.65, 95% CI = -3.67 to -1.63, p < 0.001), while mesenchymal stem cells (MSCs) injection improved the clinical outcomes (SMD = 2.37, 95% CI = 1.25-3.50, p < 0.001). There were significant differences between the two groups in arthroscopic (SMD = 1.38, 95% CI = 0.82-1.94, p < 0.001) and histologic results (relative risk [RR] = 1.77, 95% CI = 1.36-2.29, p < 0.001). The pain relief (MD = 0.17, 95% CI = -3.26 to 3.61, p = 0.92) and operative complications (RR = 1.42, 95% CI = 0.83-2.42; p = 0.19) of the two groups had no significant differences. Our analysis supports that concurrent cartilage repair procedures might improve arthroscopic and histologic outcomes, but they have no beneficial effect on clinical outcomes, radiograph, MRI, and pain relief. The concurrent procedures do not increase the risk of operative complication. Furthermore, MSC has some beneficial effects on clinical outcomes, while AA might play an opposite role.

Type of bone graft and primary diagnosis were associated with nosocomial surgical site infection after high tibial osteotomy: analysis of a national database

PURPOSE

Although several small-scale studies have reported risk factors for surgical site infection (SSI) after high tibial osteotomy (HTO), no study has collectively analysed risk factors in a large cohort. The present study aimed to clarify the risk factors for SSI after HTO using a national database.

METHODS

Data of inpatients who underwent HTO from 2010 to 2017 were obtained from the Diagnosis Procedure Combination database in Japan. Outcome measures were the incidence of SSI and deep SSI after HTO. Associations between SSI and patient data were examined with multivariable logistic regression analysis.

RESULTS

Among 12,853 patients who underwent HTO, 195 developed SSI (1.52%) and 50 developed deep SSI (0.39%). Univariate analysis showed that male sex, smoking, and longer anaesthesia duration were associated with higher incidences of SSI, whereas a primary diagnosis of osteonecrosis and use of natural bone grafts were associated with lower incidences. In multivariable analysis, SSI was positively associated with male sex, anaesthesia duration longer than 210 min (vs. 150-210 min), and use of artificial bone graft (vs. natural bone graft). SSI was negatively associated with age ≤ 49 years (vs. 50-59 years) and a primary diagnosis of osteonecrosis (vs. osteoarthritis).

CONCLUSION

The present study revealed novel risk factors for SSI after HTO that previous studies have failed to find, including use of artificial bone graft and longer anaesthesia duration; primary diagnosis of osteonecrosis and younger age were novel protective factors. These findings will help surgeons assess risks of SSI after HTO in individual patients.

LEVEL OF EVIDENCE

III.

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

PURPOSE

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.

METHODS

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).

RESULTS

Mean follow-up was 11.9 ± 7.2 years. 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 10 years, 82% at 15 years and 80% at 20 years. Sixteen revisions (9.6%) were reported at a mean period of 12.8 years.

CONCLUSIONS

CW-HTO is a valid option for medial osteoarthritis treatment, with successful results in both clinical and radiological outcomes.

LEVEL OF EVIDENCE

IV.

Treatment of aseptic nonunion after medial opening-wedge high tibial osteotomy

BACKGROUND

Nonunion after medial opening-wedge high tibial osteotomy (OWHTO) is a rare but serious complication with very limited data regarding its treatment. The aim of this study was to analyze the healing rate after operative treatment of nonunion after OWHTO.

METHODS

We performed a single-center, retrospective study that included 14 patients with nonunion after OWHTO between 2010 and 2018. The treatment for all patients consisted of local debridement and cancellous bone grafting at the osteotomy gap. Revision osteosynthesis due to a loss of correction/loosening of the locking screws or plates was performed in 5 patients. In 7 patients, lateral hinge fractures were treated with additional lateral plating. Union was confirmed using the modified "Radiographic Union Score for Tibial fractures". Outcome measure was the Lysholm Knee Score at final follow-up.

RESULTS

The mean age of the patients included in our study was 48.4 ± 6.7 years. Three patients were female (21.4%). The mean follow-up period was 20.8 ± 12.8 months. Union was achieved in 12/14 patients (85.7%) after a mean of 6 months (range, 3-13). The mean Lysholm Knee Score at the final follow-up was 83.2 ± 11.6. Two patients did not reach definitive union during the follow-up. In one patient, an infection of the nonunion following bone grafting was successfully treated with a two-stage procedure. Two patients needed additional cancellous bone grafting 6 and 8 months after the first revision surgery. All patients showed pain-free full weight bearing after union was achieved.

CONCLUSIONS

Nonunions after OWHTO can generally be treated successfully with cancellous bone grafting. For patients who have loss of correction, loosening of the osteosynthetic material or fracture of the lateral hinge, an additional revision or additive osteosynthesis may be required.

LEVEL OF EVIDENCE

Grade III.

Relationship between the bony correction angle and mechanical axis change and their differences between closed and open wedge high tibial osteotomy

BACKGROUND

The purpose of this study was to investigate the relationship between the bony correction angle and mechanical axis change and their differences between closed wedge high tibial osteotomy (CWHTO) and open wedge high tibial osteotomy (OWHTO).

METHODS

A total of 100 knees of 89 patients who underwent OWHTO (50 knees) or CWHTO (50 knees) between 2011 and 2015 with a clinical follow-up for 1 year and a radiological follow-up for 1 month were investigated in a case control study. Anteroposterior radiographs of the knee and full-length leg were taken in the standing position using digital acquisition. The femorotibial angle (FTA), % mechanical axis deviation (MAD), % anatomical tibial axis deviation (ATAD), % mechanical tibial axis deviation (MTAD), mechanical medial proximal tibial angle (mMPTA), and joint line convergence angle (JLCA) were measured on preoperative and postoperative radiographs using a dedicated software.

RESULTS

CWHTO resulted in a greater variation between the tibial anatomical and mechanical axes than OWHTO (P <  0.05), and a greater soft tissue correction than OWHTO (P <  0.05). However, no significant difference was found between CWHTO and OWHTO in the ratio of MAD change to the correction angle. When the osteotomy was planned with the same bony correction angle, %MAD passed more laterally in OWHTO than in CWHTO (P <  0.05). These results suggested a lesser valgus bony correction ratio due to greater medial shift of the tibial axis and greater valgus compensation of the soft tissue in CWHTO compared to OWHTO.

CONCLUSIONS

The ratio of mechanical axis shift to the correction angle differed in preoperative planning, but postoperative alignment was comparable between opening wedge and closed wedge high tibial osteotomy.

Editorial Commentary: Measurements for Successful High Tibial Osteotomy: Understanding Supine Versus Standing and Intraoperative Fluoroscopic Alignment Is Required

A high tibial osteotomy (HTO) that is used to correct varus malalignment, such as with medial arthrosis or before cartilage restoration or posterolateral reconstructions, represents an important and required surgery for clinical success. A major problem that occurs with HTO planning is that the preoperative measurements, with either lower limb supine or standing weight-bearing radiographs, will invariably show abnormal medial or lateral tibiofemoral compartment opening resulting from soft-tissue laxity or injury. It is imperative that this tibiofemoral joint opening be accounted for in the osteotomy correction calculations. There are well-described methods available that affect operative planning, such as the use of preoperative stress radiographs to determine the millimeters of tibiofemoral opening or closure. The use of intraoperative fluoroscopy with application of axial loading to the lower limb and verification of closure of the tibiofemoral joint is recommended. A careful fluoroscopic examination of the tibiofemoral compartments allows a final adjustment of the osteotomy correction and confirms the final weight-bearing line percent measurement and limb alignment. Postoperative radiographs are required to detect outliers resulting from unexpected soft-tissue laxity or inadequate correction.

Day-Case Opening Wedge High Tibial Osteotomy With Intraosseous PEEK Implant

Purpose

To evaluate the short-term clinical outcomes, complications, hospitalization time, and readmission rate related to day-case opening wedge high tibial osteotomy (OWHTO) with intraosseous PEEK (polyether ether ketone) implant, in the treatment of knee osteoarthritis.

Methods

An observational study on patients treated with OWHTO using intraosseous PEEK implant was performed with a period of 12 months follow-up. Grade of Knee Injury and Osteoarthritis Outcome Score (KOOS) was assessed preoperatively, at 6 months, and at 12 months postoperatively. A simple t test was used to analyze the outcomes. P values <.05 were considered significant. Complications and revision surgeries were registered.

Results

In the period from 2016 to 2017, a consecutive group of 40 patients (13 female, 27 male) with symptomatic medial knee osteoarthritis and varus malalignment were included in the study. The average age of the patients was 54.9 (± 7.6) years. In total, 30 (77%) patients met the criterion for minimal clinically important difference in KOOS scores. The KOOS symptoms improved from 58.1 ± 20 to 78.5 ± 16.5 (P < .0001), pain from 48.1 ± 18.2 to 78.6 ± 18.5 (P < .0001), activities of daily living from 59.0 ± 19.5 to 84.1 ± 15.2 (P < .0001), sport from 23.2 ± 17.6 to 55.6 ± 26.3 (P < .0001), and quality of life from 28.4 ± 12.8 to 61.5 ± 22.5 (P < .0001) at 1-year follow-up. The average hospitalization time at the Day Surgery Unit was 5.6 ± 0.7 hours, and 4 (10%) patients had to be readmitted to the hospital within 2 weeks postoperatively. The overall complication rate was 18%. Complications that required revision surgery were registered in 4 patients (10%), including 2 non-unions and 2 progressions of osteoarthritis.

Conclusions

The day-case OWHTO with intraosseous PEEK implant was a success in 77% of the cases. The results and complications were comparable with other published studies. Despite a short hospitalization time, the readmission rate was low.

Level of Evidence

IV, therapeutic case series.

Patient Characteristics Related to Blood Loss in High Tibial Osteotomy in Novel Multiple Linear Regression Analysis

The purpose of the study was to identify patient characteristics related to blood loss following high tibial osteotomy (HTO). We evaluated 48 patients undergoing HTO from August 2018 to August 2019. The data of 48 patients were collected, including gender, age, height, weight, body mass index (BMI), smoking, alcohol consumption, hypertension, diabetes, history of aspirin, and pre-postoperative hematocrit (Hct). Multiple linear regression analysis was used to analyze the risk factors related to blood loss in HTO. The mean age of patients was 56.6 ± 10.2 years, including 22 males and 26 females. The mean BMI was 28.5 ± 4.2 kg/m², and the mean blood loss volume was 383.3 ± 181.3 mL, 13 patients with smoking (27.1%), 15 patients with alcohol consumption (31.3%), 23 patients with hypertension (47.9%), 10 patients with diabetes mellitus (20.8%), and 12 patients with history of aspirin (25.0%). Multiple linear regression model suggested alcohol consumption and BMI were associated with blood loss in HTO, R² = 0.451, F(9, 38) = 3.462 (P < 0.05). Our study indicates that alcohol consumption and BMI are important risk factors related to blood loss in HTO.