A retrospective analysis of medial opening wedge high tibial osteotomy for varus osteoarthritic knee

Earlier consolidation and improved knee function of medial open wedge high tibial osteotomy with autologous bone graft

PURPOSE

Medial knee osteoarthritis can be treated with medial open wedge high tibial osteotomy (OWHTO). We sought to investigate osseous consolidation of the osteotomy with and without autologous bone grafts (ABG) to detect possible benefits of ABG in osseous healing and functional outcome.

METHODS

In this prospective study, patients without graft transplantation were compared to those receiving ABG after medial OWHTO. They were followed up 6 weeks, 12 weeks, 6 months and 12 months postoperatively. Radiographic progress of consolidation, clinical scores, contrast-enhanced ultrasound (CEUS) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) were assessed at each appointment.

RESULTS

A total of 35 patients were enrolled, 20 without and 15 with graft transplantation. Radiologic evaluation showed a significantly earlier consolidation of the osteotomy gaps (p = 0.012) in patients with ABG, resulting in a significantly higher rate of consolidation 12 months after surgery (60% without bone graft vs. 100% with bone graft, p = 0.006). At 6 weeks as well as 6-month follow-up, a tendency of earlier consolidation with ABG was apparent, but not statistically significant (6 weeks: 50% vs. 80%, p = 0.089; 6 months: 30% vs. 60%, p = 0.097). CEUS and DCE-MRI showed physiological perfusion of the osteotomy gaps in both groups. A tendency to better function and less pain in patients with ABG was recognizable.

CONCLUSION

In our study, autologous bone grafting evocated earlier osseous consolidation after medial OWHTO and showed a tendency to a better functional outcome.

Superior survivorship and plate-related results of TomoFix compared to Puddu plate fixation for opening-wedge high tibial osteotomy: A systematic review of the literature

PURPOSE

This systematic review aimed to compare survivorship and plate-related results of Puddu and TomoFix plates in opening-wedge high tibial osteotomy (OWHTO).

METHODS

PubMed, Scopus, EMBASE, and CENTRAL databases were searched from January 2000 until September 2021 for clinical studies involving patients with medial compartment knee disease and varus deformity undergoing OWHTO using the Puddu or TomoFix plating systems. We extracted survival data, plate-related complications, and functional and radiological outcomes. The risk of bias assessment had been carried out using Cochrane Collaboration's quality assessment tool for randomised controlled trials (RCTs) and Methodological Index for Non-Randomised Studies (MINORS).

RESULTS

Twenty-eight studies were included. The total number of knees was 2568 in 2372 patients. The Puddu plate was used in 677 knees, while the TomoFix plate was used in 1891. The follow-up ranged from 5.8 to 147.6 months. Both plating systems were able to delay conversion to arthroplasty at different follow-up intervals. However, osteotomies fixed by the TomoFix plate achieved higher survival rates, especially at mid-term and long-term follow-ups. In addition, fewer complications were reported with the TomoFix plating system. Although both implants achieved satisfactory functional outcomes, high scores could not be maintained throughout long-term intervals. Regarding radiological results, TomoFix plate was able to achieve and maintain larger degrees of varus deformity, while preserving the posterior tibial slope.

CONCLUSIONS

This systematic review demonstrated the superiority of the TomoFix over the Puddu system as a safer and more effective fixation device in OWHTO. Nevertheless, these results should be interpreted with caution due to the lack of comparative evidence through high-quality RCTs.

Vancomycin-soaked femoral head allograft in opening wedge high tibia osteotomy enables earlier postoperative recovery and reduces infection rates compared to allogenic bone chips

PURPOSE

To investigate the benefits of vancomycin-soaked femoral head allograft versus allogenic bone chips as an osteotomy gap filler in reducing infection rates and perioperative pain control after medial opening wedge high tibial osteotomy (MOW-HTO).

METHODS

Retrospective analysis of 114 knees that underwent MOW-HTO between 2013 and 2020. Osteotomy gaps were filled with vancomycin-soaked femoral head allograft (Study Group) or allogenic bone chips (Control Group). Both groups received systemic antibiotics. Perioperative parameters studied included pain, blood loss, length of stay, postoperative day (POD1) pain scores at rest, with activity as well as ambulatory distance. Patients in the Study Group were also followed up prospectively and clinical outcome scores, namely Knee Society Score, Oxford knee score (OKS) and Physical and Mental Component of the Short-Form 36 Questionnaire (PCS and MCS, respectively). Statistical analyses using Student's T-test were performed between the groups.

RESULTS

Patients of the study group had significantly better POD1 visual analogue scale (VAS) at rest (0.9 ± 1.6 vs 2.9 ± 1.2, p < 0.001) as well as when active (3.0 ± 1.9 vs 5.8 ± 1.5, p < 0.001). A greater proportion of patients in the study group ambulated on POD 1, (90.6% vs 26.0%, p < 0.001). Of those who ambulated on POD1, study group patients managed to cover a greater ambulatory distance (13.9 ± 7.4 m vs 8.4 ± 9.3 m, p < 0.05). The proportion of study group patients requiring patient-controlled analgesia (PCA) was also significantly less compared to the control group (32.8% vs 58.0%, p < 0.05). Of those requiring PCA, the amount of morphine requirement was also significantly reduced in the group with vancomycin-soaked allograft (8.7 ± 8.1 mg vs 23.9 ± 33.0 mg, p < 0.05). The study group also had a reduced length of stay (3.5 ± 2.0 days vs 5.5 ± 2.6 days, p < 0.001). Patients in the study group demonstrated significant improvement in Knee Society Knee Score (KSKS), OKS, PCS and MCS at 12 months postoperatively. The study group had a significantly reduced incidence of superficial wound infections compared to the control group (3.1% vs 18.0%, p < 0.05).

CONCLUSION

Vancomycin-soaked femoral head allograft reduced superficial and deep wound infections in MOW-HTO. It was also effective in reducing postoperative pain, thereby enabling early ambulation and shorter hospital stays.

LEVEL OF EVIDENCE

Retrospective comparative study, III.

Medial compartment cartilage repair and lower extremity biomechanical changes after single-plane high tibial osteotomy of distal tibial tuberosity

OBJECTIVE

To observe the cartilage repair of the medial compartment and the biomechanical changes of the lower extremities after single-plane high tibial osteotomy of distal tibial tuberosity (DTT-HTO).

METHODS

A total of 30 patients, including 11 males and 19 females, who underwent DTT-HTO with arthroscopic operation in our hospital from January 2020 to January 2021 and underwent arthroscopic exploration again during the second operation for internal fixation were enrolled. There were 32 knees, including 13 left knees and 19 right knees. Age ranged from 50 to 78, with an average of 63.20 ± 6.61 years old. All patients completed two surgeries and were followed up, and no adverse events occurred during the period. International Cartilage Repair Society (ICRS) was used to assess the cartilage condition of the medial compartment of the knee during the two surgeries. In this paper, the weight-bearing line ratio (WBLR), the medial proximal tibia angle (MPTA), the femoral tibial angle (FTA) and the posterior tibial slope (PTS) were used to evaluate the changes of the mechanical state of the lower limbs. The visual analogue scale (VAS) score and the Western Ontario and McMaster University Osteoarthritis (WOMAC) Index score were used to evaluate the improvement in knee pain and function.

RESULTS

All patients completed two operations without adverse events and serious complications. The medial compartment cartilage of all patients had different degrees of repair during the second operation, and the difference was statistically significant compared with the first operation (P < 0.05). During the second operation, the WBLR was corrected from (17.69 ± 2.16)% to (60.90 ± 1.97)%, the MPTA was corrected from (80.72 ± 1.61)° to (89.91 ± 2.58)°, the FTA was corrected from (182.31 ± 3.03)° to (171.81 ± 2.24)°, the difference was statistically significant (P < 0.05). There was no statistical difference in PTS between the two surgeries (P > 0.05). At the second operation, the VAS score decreased from 7.50 ± 1.34 to 0.34 ± 0.85, the WOMAC score decreased from 119.50 ± 10.43 to 46.25 ± 4.13, and the difference was statistically significant (P < 0.05).

CONCLUSION

DTT-HTO can significantly correct the weight-bearing line, restore the biomechanical parameters of the lower limb to the normal range, significantly relieve pain and improve knee function, and the medial compartment cartilage repair and regeneration phenomenon will occur after the correction of the weight-bearing line.

Complications, Additional Surgery, and Joint Survival Analysis After Medial Open-Wedge High Tibial Osteotomy

The reported incidence of complications following medial open-wedge high tibial osteotomy (MOWHTO) varies. The authors sought to assess the complications, additional surgeries, and joint survival following MOWHTO in patients with isolated medial compartment arthrosis during a mean follow-up of 10 years. This retrospective study involved patients implanted with spacer plates, angle adjustable plates, or inverse L-type plates with wedges between 2000 and 2010. A total of 504 knees from 441 patients were examined. Mean age of the study population was 52.6±7.0 years, with 56 (11.1%) knees from men and 448 (88.9%) from women. The 10-year Kaplan-Meier joint survival rate was 94.8%. Overall complication rate for MOWHTO was 63.7%, with complications in 20.3% of treated knees requiring additional surgery. In this population, although the overall complication rate and the need for additional surgery were high, the need for additional surgery resulting from serious complications was low (2.6%). The high joint survival rate and low rate of additional surgery for serious complications indicate that MOWHTO can be safely applied in patients with isolated medial gonarthrosis. [Orthopedics. 2020;43(5):303-314.].

Mid-term CT assessment of bone healing after nanohydroxyapatite augmentation in open-wedge high tibial osteotomy

BACKGROUND

The aim of the present study was to confirm the effectiveness of adding nanohydroxyapatite (NHA) to a heterologous bone graft in open-wedge high tibial osteotomy (OWHTO) by measuring the bone density via multislice computed tomography (CT) of the tibial osteotomy gap in a mid-term follow-up (five years).

METHODS

Twenty-six patients undergoing OWHTO were randomly assigned to two groups: a pure graft group (Group A), in which the osteotomy gap was filled with only heterologous bone graft, and an NHA group (Group B), in which the osteotomy gap was filled with heterologous bone graft and NHA. CT was performed within one week of the operation, after two months, after 12 months and after five years. CT volume acquired in Hounsfield units (HU) was measured on three planes.

RESULTS

The normal bone density was 110.2 ± 11.7 HU. The value of mean density at five years in Group A was 296.8 ± 81.8 HU, while in Group B, it was 202.2 ± 45.1 HU, showing a density more similar to normal bone and greater bone uniformity inside the osteotomy. The difference between the two groups was statistically significant (p < 0.05). Furthermore, both groups showed excellent mid-term clinical outcomes without significant differences.

CONCLUSIONS

This study revealed that absorbability and bone formation at the osteotomy site in the NHA group was significantly higher as compared with the pure graft group at five years postoperatively.

Is iliac autogenous graft augmentation in medial open wedge high tibial osteotomies superior to no augmentation in terms of bone healing?

OBJECTIVES

This study aims to investigate if iliac autogenous graft augmentation in medial open wedge high tibial osteotomies (OWHTOs) is superior to no augmentation in terms of bone healing.

PATIENTS AND METHODS

Twenty-five patients (14 males, 11 females; mean age 40.9±4.0 years; range, 33 to 48 years) with medial compartmental osteoarthritis of knee joint who underwent high tibial osteotomy with medial open wedge between January 2016 and December 2018 were included in this retrospective study. Twelve of the operated knees were the right knee. Graft was used in 13 patients (52%). Data including age, gender, body mass index (BMI), direction, follow-up period, union, Lysholm and International Knee Documentation Committee (IKDC) scores, pre- and postoperative femoral tibial angles (FTAs) and posterior tibial slopes were evaluated.

RESULTS

The mean BMI was 26.4±1.9 (range, 22.0 to 30.0). Only 48% of the patients were smoking. The mean follow-up period was 28.6±5.3 months (range, 24 to 38 months). No statistically significant difference was found between the grafted and non-grafted groups in terms of age, BMI, follow-up time, gender, side and smoking status (p>0.05) There was no statistically significant difference between two groups in terms of pre- and postoperative Lysholm scores, pre- and postoperative IKDC scores, or pre- and postoperative FTA values (p>0.050).

CONCLUSION

Iliac autogenous graft augmentation in medial OWHTO has no effect on union but shortens the union time. Preoperative high varus degree adversely affects union. Therefore, routine use of iliac crest autograft is not recommended.

Development and validation of a finite element model to simulate the opening of a medial opening wedge high tibial osteotomy

Medial opening wedge high tibial osteotomy (MOWHTO) is a surgical procedure intended to alter the coronal and sagittal plane alignment of the lower limb to primarily relieve the symptoms of osteoarthritis in the medial compartment of the knee. The purpose of this work was to develop and validate a finite element model to simulate the opening of a high tibial osteotomy and determine whether a pilot hole at the cortical hinge reduces the risk of lateral cortical fracture. Fifteen models were reconstructed from CT images of eight cadaveric specimens. The validated models indicated that the addition of the pilot hole increased the stresses and likelihood of a type-I and type-II fractures during the opening of a medial open wedge high tibial osteotomy compared to the no-hole condition.

A Retrospective Comparison of Union Rates After Open Wedge High Tibial Osteotomies With and Without Synthetic Bone Grafts (Hydroxyapatite and β-tricalciumphosphate) at 2 Years

PURPOSE

To evaluate the clinical and radiological results of no bone graft (NBG) after opening wedge high tibial osteotomy (OWHTO) with a locking plate and to compare the bone union rate between the synthetic bone graft (SBG) group and the NBG group after OWHTO using serial radiographs.

METHODS

From 2012 to 2015, OWHTOs were performed with SBG or without bone graft using long locking plates. Inclusion criteria were: (1) OWHTO for disease of the medial compartment with varus deformity, and (2) minimum 2-year follow-up and radiographs taken serially to 2 years. Exclusion criteria were: (1) follow-up period <2 years (n = 8) or (2) absence of at least 1 radiograph taken at each follow-up point (n = 14). We retrospectively reviewed radiographs taken preoperatively and at 6 weeks, 3 months, 6 months, 1 year, and 2 years postoperatively. Groups comprised those filled with a synthetic bone [hydroxyapatite (HA) and β-tricalciumphosphate (TCP), n=33, SBG group] or without a bone graft (n = 38, NBG group). We compared bone union rate between the 2 groups by measuring the union zone from zone 1 to zone 5 in serial radiographs using Fisher's exact test.

RESULTS

OWHTO was performed in a total of 93 knees and 71 knees were included in this study. Both groups showed good clinical and radiological results without correction loss at 2 years. The entire NBG group and 93.9% of the SBG group showed union over zone 3 at 2 years. However, the NBG group showed significantly more incorporation than the SBG group at 6 months (P = .006), 1 year (P = .0003), and 2 years (P = .0003).

CONCLUSIONS

Union without correction loss was obtained after OWHTO without bone graft. The NBG group showed significantly more incorporation than the SBG group (HA and β-TCP) within 2 years.

LEVEL OF EVIDENCE

Level IV, case series.

Survivorship of medial opening wedge high tibial osteotomy in the elderly: two to ten years of follow up

BACKGROUND AND PURPOSE

Medial opening wedge high tibial osteotomy (MOWHTO) is a well-accepted procedure, which has been widely used for pain relief and varus deformity correction in the osteoarthritic (OA) knee, especially in the young patient. However, in the elderly patient, the efficacy of this procedure is still unknown. Therefore, this study aims to evaluate the survivorship of MOWHTO in elderly patients as the primary outcome. The secondary outcome is to evaluate the loss of correction angle that is the common complication after MOWTHO.

MATERIALS AND METHOD

A retrospective study of 50 elderly patients (≥ 60 years) was conducted to track survivorship of MOWHTO. All patients were diagnosed with varus OA knee and underwent MOWHTO at our institute. The patients who had previous knee surgery or incomplete data were excluded. Medical records and radiographs of eligible patients were reviewed for recruiting the data. Survivorship of MOWHTO was analyzed using Kaplan-Meier curves. The starting point was the time of operation and the end point was the time of subsequent TKA. The loss of correction angle was defined as the change of medial proximal tibial angle (MPTA) between three months and one year post-operatively.

RESULTS

The mean age of patients was 66 ± 5.0 years. The majority of patients were female (74%). The mean correction angle was 10.6 ± 3.6 degrees. The union rate of osteotomy site was 100%. In survival analysis, the median follow-up time was 6.0 ± 3.0 years. Two patients required subsequent conversions to TKA. The survivorship of MOWHTO at four years was 95.5% (95%CI, 96.0 to 98.0). For radiographic assessment, the loss of correction angle was 1.0 ± 0.5 degrees at one year post-operatively.

CONCLUSION

This study proved that MOWHTO in patient ≥60 years had good mid-term survivorship with acceptable complications. This procedure can be the alternative option for the treatment of varus OA knee in the elderly.

Return to Work and Sport Following High Tibial Osteotomy: A Systematic Review

BACKGROUND

The purpose of this study was to examine (1) timelines for return to sport and work following high tibial osteotomy (HTO), and (2) whether patients return to sport and work at levels similar to preoperative levels.

METHODS

A systematic search was conducted across 3 databases (MEDLINE, Embase, and PubMed). Two reviewers independently screened the results for relevant articles. Data regarding patient demographics, indications, surgical technique, return to work and sport, and complication and failure rates were abstracted from eligible studies.

RESULTS

Nineteen studies were included, involving 1,189 patients (64% male, 21% female, 15% unspecified) and 1,224 knees. Mean age was 46.2 years (range, 16 to 80 years). Opening-wedge HTO was most commonly used, followed by closing-wedge HTO and hemicallotasis. Mean follow-up was 65.4 months (range, 8 to 253 months). Overall, 87.2% of patients returned to sport postoperatively, and 78.6% returned at an equal or greater level. Among competitive athletes, 54% returned to competition. Overall, 84.5% of patients returned to work postoperatively, and 65.5% returned at an equal or greater level. Approximately 90% of patients who returned to work or sport did so within 1 year. The complication rate was 5.8%, with infection being the most common complication; 7.0% of patients progressed to a total knee arthroplasty at a mean of 6.7 years (range, 0.8 to 15 years) following HTO.

CONCLUSIONS

The majority of patients undergoing HTO return to sport and work, and most return within 1 year of the operation. Most patients return to sport at a level equal to or greater than the preoperative level. Approximately two-thirds of patients return to an equal or greater level of physical work.

LEVEL OF EVIDENCE

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

Complications associated with opening wedge high tibial osteotomy--A review of the literature and of 15 years of experience

BACKGROUND

Complication rates following opening wedge high tibial osteotomy (OWHTO) is an issue that has not been comprehensively addressed in current literature.

METHODS

We performed a retrospective study of local patients who underwent OWHTO for isolated medial compartment knee osteoarthritis from 1997 to 2013. We analysed survivorship and complication rates and compared this to a literature review of previously reported data.

RESULTS

One hundred and fifteen patients met the inclusion criteria. Mean follow-up=8.4 years. Mean age=47 (range 32 to 62). Mean Body Mass Index (BMI)=29.1 (range 20.3 to 40.2). Devices used consisted of Tomofix (72%), Puddu plate (21%) and Orthofix (seven percent) (no significant differences in age/sex/BMI). Wedge defects were filled with autologous graft (30%), Chronos (35%) or left empty (35%). Five years survival rate (without requiring conversion to arthroplasty)=80%. Overall complication rate=31%. Twenty five percent of patients suffered 36 complications including minor wound infections (9.6%), major wound infections (3.5%), metalwork irritation necessitating plate removal (seven percent), non-union requiring revision (4.3%), vascular injury (1.7%), compartment syndrome (0.9%), and other minor complications (four percent). No thromboembolic complications were observed.

CONCLUSION

No significant differences existed in complication rates following OWHTO relative to BMI, implant type, type of bone graft used or patient age at surgery. When the complications from OWHTO were analysed closely they appear higher than previously reported in the literature; however serious complications appear rare. LEVEL OF EVIDENCE 3: Retrospective cohort study.

Prospective study of the anterior cruciate ligament reconstruction associated with high tibial opening wedge osteotomy in knee arthritis associated with instability

INTRODUCTION

Chronic ACL insufficiency with associated varus malalignment due to knee osteoarthritis (OA) is challenging to treat surgically. A combined ACL reconstruction (ACLR) with medial open wedge high tibial osteotomy (HTO) without using any metallic implant for HTO is an effective technique.

MATERIALS AND METHOD

All the patients attending the outpatient department ACL injury and with associated medial compartment OA (Kellegren's grade 2 and grade 3) were considered for inclusion in the study. Forty patients who met inclusion criteria were included in the study. Simultaneous ACLR (single bundle of quadrupled hamstring graft fixed with Endobutton on femoral side and biointerference screw on the tibial side) along with medial opening wedge osteotomy (with tricalcium phosphate wedge) was done. The patients were assessed with IKDC, KOOS scores and any change in anterior tibial translation was also checked.

RESULTS

The combined procedure showed mean varus angle correction of 9° (10.5-1.5°), and the mechanical axis of the knee was restored from an average of 172-181.5°. There was a significant improvement in knee score (KOOS and IKDC) after the surgery (p < 0.05). The average time for the radiological union of the osteotomy was 3.56 months. The anterior tibial translation was improved. No intraoperative complications and slippage of the synthetic graft were noted in any case.

CONCLUSIONS

Combined ACLR with HTO (using TCP wedge, without any hardware) is a reliable method that prevents rapid progression of OA. It reliably corrects varus deformity and obviates the use of any hardware.

Is Bone Grafting Necessary in Opening Wedge High Tibial Osteotomy? A Meta-Analysis of Radiological Outcomes

Purpose

Bone grafting in opening wedge high tibial osteotomy (OWHTO) is still controversial. The purpose of this study is to compare the radiological outcomes of OWHTO with bone graft (autogenous, allogenous, and synthetic bone graft) and those without bone graft.

Materials and Methods

PubMed, MEDLINE, EMBASE and Cochrane Register of Studies databases were searched using specific inclusion and exclusion criteria for radiological studies involving OWHTO with bone graft and without bone graft groups. All reported delayed union, nonunion and correction loss were analyzed. Data were searched from the time period of January 2000 through July 2014. In addition, a modified Coleman methodology score (CMS) system was used to assess the methodological quality of the included studies.

Results

Twenty-five studies with a mean CMS value of 77 (range, 61 to 85 score) were included. In total, 1,841 patients underwent OWHTO using 4 different procedures for bone graft: autobone graft (n=352), allobone graft (n=547), synthetic bone graft (n=541) and no bone graft (n=401). There was a similar tendency for delayed union, nonunion and correction loss rate among the osteotomy space filling methods.

Conclusions

The meta-analysis showed there was a similar tendency for radiological union and correction maintenance among patients undergoing OWHTO regardless of the type of bone in all of the studies. However, the currently available evidence is not sufficient to strongly support the superiority of OWHTO with bone graft to OWHTO without bone graft.

A report of nonunion at medial wedge high tibial osteotomy site and its management

High tibial osteotomy (HTO) is an accepted treatment option for correcting deformities and reducing pain in the treatment of uni-compartment osteoarthritis of the knee. The principle is to redistribute the weight-bearing load. Medial open wedge HTO (MOWHTO) has gained popularity over lateral closed wedge osteotomy due to its decreased incidence of complications. MOWHTO surgical techniques have many variations in fixation techniques and in the use of bone grafts or bone substitute augmentation. In spite of the existing guidelines, there are no clear indications of grafting at the osteotomy site. Delayed union and nonunion although are possible complications, nonunion is especially rarely reported. Thus authors in this case report, like to point attention towards this under-reported complication and its management.