Distal Femoral Varus Osteotomy for the Management of Valgus Deformity of the Knee

Deformity in valgus knee malalignment is not only in the femur but also in tibia or both, based on demographic and morphological analysis before and after knee osteotomies

PURPOSE

This study aims to identify the demographic and morphological features of valgus knee deformity with unilateral osteoarthritic knee in the coronal plane. A secondary aim was to identify the distinct phenotypes of valgus knees in Hirschmann's phenotype and the coronal plane alignment of the knee (CPAK) classifications before and after a knee osteotomy (KO).

METHODS

A total of 107 patients (57 female and 50 male) with a mean age of 42.4 ± 17.2 years, who underwent varisation osteotomy for symptomatic unilateral knee osteoarthritis (OA) and constitutional valgus deformity, were enrolled in the study, and the mean follow-up period was 29.1 ± 7.3 months. The included cases comprised 60 cases of distal femoral osteotomy, 10 cases of double-level osteotomy and 33 cases of high tibial osteotomy. All patients underwent preoperative and postoperative clinical, functional and radiological evaluations, analysed by analysis of variance tests.

RESULTS

An analysis of the location of the valgus deformities demonstrated that 56 cases (52.3%) were femoral based, 18 cases (16.8%) were both femoral and tibial based and 33 cases (30.9%) were tibial based. Twelve preosteotomy cases (11.2%) and 38 postosteotomy cases (35.5%) matched the most common eight Hirschmann's phenotypes, phenotyping the coronal lower limb alignment based on the native alignment in young patients without OA. Four (3.7%) preosteotomy cases and 89 postosteotomy cases (83.1%) matched the most common three CPAK phenotypes (Ⅰ, Ⅱ, Ⅴ) based on constitutional alignment and joint line obliquity in healthy and osteoarthritic knees.

CONCLUSION

In valgus knee malalignment, the location of the deformity is not only solely femoral-based but also solely tibial-based or combined femoral and tibial-based. An individualised osteotomy approach would be recommended to achieve careful preoperative planning that considers the location of the deformity and the resultant joint line. Hirschmann's and CPAK classification would not be relevant when KO is considered.

LEVEL OF EVIDENCE

Level Ⅳ, retrospective case-control study.

Comparison of double chevron-cut and biplanar distal femoral osteotomy techniques: A biomechanical study

OBJECTIVE

This study aimed to compare the stability and mechanical properties of the double chevron-cut (DCC) and biplanar (BP) distal femoral osteotomy (DFO) techniques, along with analyzing their respective contact surface areas.

METHODS

Biomechanical testing was performed using sawbone and 3D modeling techniques to assess axial and torsional stability, torsional stiffness, and maximum torque of both osteotomy configurations. Additionally, 3D models of the sawbone femur were created to calculate and compare the contact surface area of the DCC, BP, and conventional single-plane DFO techniques.

RESULTS

Axial stiffness and maximum strength did not significantly differ between the two osteotomy techniques. However, in terms of torsional properties, the DCC technique exhibited superior torsional stiffness compared to the BP group (27 ± 7.7 Nm/° vs. 4.5 ± 1.5 Nm/°, p = 0.008). Although the difference in maximum torque did not reach statistical significance (63 ± 10.6 vs. 56 ± 12.1, p = 0.87), it is noteworthy that the DCC group sawbone model exhibited fracture in the shaft region instead of at the osteotomy site. Therefore, the actual maximum torque of the DCC construct may not be accurately reflected by the numerical values obtained in this study. The contact surface area analysis revealed that the BP configuration had the largest contact surface area, 111% larger than that of the single-plane configuration. but 60% of it relied on the less reliable axial cut. Conversely, the DCC osteotomy offered a 31% larger contact surface area than the single-plane configuration, with both surfaces being weight-bearing.

CONCLUSION

The DCC osteotomy exhibited superior mechanical stability, showing improved rotational stiffness and maximum torque when compared to the BP osteotomy. Although the BP osteotomy resulted in a larger contact surface area than the DCC osteotomy, both were larger than the conventional single-plane configuration. In clinical practice, both the DCC and BP techniques should be evaluated based on patient-specific characteristics and surgical goals.

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.

Mid-term outcomes of temporary medial distal femoral hemiepiphysiodesis with and without medial patellofemoral ligament repair for recurrent patellar instability in skeletally immature patients with genu valgum

Genu valgum contributes to patellar instability, though outcomes following temporary hemiepiphysiodesis via eight plating are less understood. The purpose of this study was to evaluate the outcomes and need for additional procedures following temporary hemiepiphysiodesis for the treatment of pediatric genu valgum and patellar instability, as well as evaluating the utility of a concurrent medial patellofemoral ligament (MPFL) repair. Patients who underwent medial distal femoral epiphysiodesis for the treatment of genu valgum and recurrent patellar instability were identified. Inclusion criteria were minimum 1-year follow-up and lack of concurrent ligamentous reconstruction. Patients were contacted to complete a questionnaire which included the International Knee Documentation Committee (IKDC) form and questions pertaining to knee function and patient satisfaction. Thirty-one patients aged 12.0 ± 1.9 years underwent 47 guided growth procedures and were included in final analysis. Seventeen knees (36%) required subsequent surgery for patellar instability. All patients requiring subsequent surgery were female, compared with 70% of patients not requiring subsequent surgery ( P  = 0.017). The MPFL repair group underwent fewer subsequent procedures to address instability, though this difference was NS (17 vs. 46%, P  = 0.318). Mean IKDC score at 5.3 years follow-up among 18 survey respondents was 78.6. Medial distal femoral hemiepiphysiodesis may partially address recurrent patellar instability in skeletally immature patients with genu valgum. Concurrent MPFL repair may minimize the need for subsequent procedures to address recurrent instability. While correcting alignment may be helpful, patients should be aware of the potential need for further patellar instability surgery. Level of evidence: IV, case series.

Comparison of Early Complication Rates After High Tibial Osteotomy Versus Unicompartmental Knee Arthroplasty for Knee Osteoarthritis

Background

Although both high tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) can be utilized to treat unicompartmental osteoarthritis (OA) in select patients, the early complication rates between the 2 procedures are not well understood. Understanding of the complication profiles for both procedures would help clinicians counsel patients with unicompartmental knee OA who may be eligible for either treatment option.

Purpose

To compare the 30-day complication rates after HTO versus UKA for the treatment of knee OA using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database.

Study Design

Cohort study; Level of evidence, 3.

Methods

NSQIP registries between 2006 and 2019 were queried using Current Procedural Terminology codes to identify patients undergoing HTO and UKA for knee OA. Patients >60 years of age were excluded. Patient demographics, preoperative comorbidities, and intraoperative data were collected. Postoperative 30-day complications, including venous thromboembolism (VTE), urinary tract infection (UTI), transfusion, surgical-site infection (SSI), and reoperations were recorded. Complication rates between treatment groups were compared using a multivariate logistic regression model adjusted for sex, age, body mass index, steroid use, respiratory status (smoking/dyspnea/chronic obstructive pulmonary disease), diabetes, and hypertension.

Results

A total of 156 patients treated with HTO and 4755 patients treated with UKA for knee OA were identified. Mean patient ages were 46 years for the HTO group and 53.4 years for the UKA group. Operative time was significantly longer in the HTO group versus the UKA group (112 minutes vs 90 minutes; P < .001). Multivariate analyses found no significant differences in VTE (1.3% vs 0.6%), UTI (0.6% vs 0.3%), transfusion (0.6% vs 0.2%), deep SSI (0.6% vs 0.1%), and reoperation (1.3% vs 1%) rates between HTO and UKA groups. The HTO group had a higher rate of superficial SSI compared with the UKA group (2.6% vs 0.6%; P = .006) (adjusted odds ratio, 4.2; 95% CI, 1.4-12.5; P = .01).

Conclusion

There were no differences in 30-day VTE, UTI, transfusion, deep SSI, and reoperation rates for HTO versus UKA in the treatment of knee OA. HTO was associated with a higher rate of superficial SSI compared with UKA. These findings serve to guide clinicians in counseling patients regarding the early risks after HTO and UKA.

Distal Femoral Osteotomy for the Management of Coronal Deformity Following Total Knee Arthroplasty: A Report of 2 Cases

CASE

We present 2 cases demonstrating the management of coronal malalignment with an existing total knee arthroplasty using opening wedge distal femur osteotomy. The mechanical axis was corrected, and the primary total knee implants were maintained. Patients resumed full activity 3 to 4 months after surgery.

CONCLUSION

In certain cases, opening wedge distal femoral osteotomy is an option to correct coronal malalignment with an existing total knee arthroplasty without revising the implant.

The Principles of Knee Joint Preservation: Operative Treatment Strategies

➤ Joint alignment, meniscal status, and ligament stability are codependent factors involved in knee joint preservation, and any injury or imbalance can impact the knee articular cartilage status and can result in adverse clinical outcomes.➤ Cartilage preservation procedures in the knee will not result in optimal outcomes if there is joint malalignment, meniscal deficiency, or ligamentous instability.➤ Lower-extremity varus or valgus malalignment is a risk factor for the failure of an anterior cruciate ligament (ACL) reconstruction. It represents an indication for a high tibial osteotomy or distal femoral osteotomy in the setting of failed ACL reconstruction, and may even be considered in patients who have an initial ACL injury and severe malalignment.➤ An elevated posterior tibial slope increases the risk of failure of ACL reconstruction, whereas a decreased posterior tibial slope increases the risk of failure of posterior cruciate ligament reconstruction.

Distal femoral osteotomy for the valgus knee: indications, complications, clinical and radiological outcome

INTRODUCTION

The aim of this study was to describe the indications and technical aspects of medial closing and lateral opening distal femoral osteotomy (MCDFO and LODFO) for patients with a valgus knee and to report clinical and radiological outcomes and complications.

METHODS

Over 6 years, 28 DFOs (22 MCDFO, 6 LODFO) were performed in 22 Patients. In this cohort study, we retrospectively analyzed clinical and radiological outcome measures as well as complications.

RESULTS

The median (range) age was 47 (17-63) years, height 1.68 (1.56-1.98) m, body mass 80 (49-105) kg, and body mass index (BMI) 27.4 (18.6-37.0) kg/m2. The clinical follow-up was 21 (7-81) months, the need for total or unicompartmental knee arthroplasty (TKA/UKA) and hardware removal was followed up for 59 (7-108) months postoperatively. Preoperatively, hip-knee-ankle angle (HKA, negative values denote varus) was 7.0 (2.0-13.0)°, mechanical lateral distal femoral angle (mLDFA) was 83.7 (79.9-88.2)°, and mechanical proximal tibial angle (MPTA) was 89.0 (86.6-94.5)°. Postoperatively, HKA was -1.3 (-9.0-1.2)° and mLDFA was 90.8 (87.3-97.3)°. The incidence of minor and major complications was 25% and 14%, the incidence of delayed and nonunion was 18% and 4%, respectively. At the last follow-up, 18% of the patients had pain at rest, 25% during activities of daily living, and 39% during physical activity, and 71% were satisfied with the outcome. 7% of the cases received a TKA/UKA, 71% received a hardware removal.

CONCLUSION

DFO is a reasonable treatment for lateral osteoarthritis in younger patients to avoid disease progression and the need for an UKA/TKA. However, there is a long rehabilitation time, a considerable risk for complications, and a high need for hardware removal. While many patients experienced symptoms at the long-term follow-up, most were satisfied with the outcome. Appropriate patient information is essential. Level of evidence Level IV, Case Series. Trial registration number NCT04382118, clinicaltrials.gov, May 11, 2020.

Patient-Specific Instrumentation for Medial Closing Wedge Distal Femoral Osteotomy With Patellar Osteochondral Allograft

The primary indications for performing a medial closing wedge distal femoral osteotomy are valgus knee malalignment, lateral knee compartment overload, lateral meniscus insufficiency, and/or lateral compartment osteoarthritis or cartilage damage. Without correction of this malalignment, there is an increased risk for chondral damage in the lateral and patellofemoral compartment of the knee. The optimal candidates for this procedure are young, active individuals with moderate to severe arthritis in the lateral compartment. Recently, preoperative planning for high tibial and distal femoral osteotomies (HTOs and DFOs) using 3-dimensional (3D) patient-specific instrumentation (PSI) has increased in popularity. Successful patient outcomes have been reported using this technique. This Technical Note illustrates our preferred technique that uses 3D PSI in addition to a patellar OCA transplant when treating a symptomatic cartilage lesion associated with genu valgum.

Effects of Lateral Opening-Wedge Distal Femoral Osteotomy on Meniscal Allograft Transplantation: A Biomechanical Evaluation

Background

Lateral meniscal deficiency with valgus malalignment increases the rate of lateral compartment osteoarthritis. Lateral meniscal allograft transplantation (LMAT) with a concomitant varus-producing opening-wedge distal femoral osteotomy (DFO) is an option yet to be evaluated biomechanically.

Purpose/Hypothesis

The purpose of this study was to clarify the biomechanical effects of the realignment procedure in the setting of LMAT. We hypothesized that (1) given the dependence of the lateral compartment on the lateral meniscus, a DFO and increasing degrees of varus would be insufficient to restore lateral compartment pressures to normal from a lateral meniscus-deficient state, and that (2) LMAT would restore lateral compartment pressures to the intact state while DFO would decrease lateral compartment pressures for any given state of the meniscus.

Study Design

Controlled laboratory study.

Methods

Ten cadaveric knees underwent opening-wedge varus-producing DFO secured by an external fixator. Anatomic alignment was standardized to 6° of mechanical valgus, and each joint was tested in full extension. Submeniscal placement of thin film pressure sensors allowed for the recording of contact pressure, peak contact pressure, and contact area. The specimens were loaded on a biaxial dynamic testing machine with loading angles between 9° valgus and 6° varus of mechanical alignment. Conditions tested included intact meniscus, meniscal deficiency, and meniscal transplantation.

Results

Isolated varus-producing DFO to 6° in the meniscus-deficient state failed to restore joint pressures and contact areas to the intact state, with significant changes in mean contact pressure (175%), mean peak contact pressure (135%), and contact area (-41%) (all P < .05 vs intact), while LMAT restored all outcome measures (all P > .05 compared with intact). After LMAT, every additional 1° of DFO correction contributed to a decrease in the mean contact pressure, peak pressure, and contact area of 5.6% (-0.0479 N/mm²), 5.9% (-0.154 N/mm²), and 1.4% (-6.99 mm²) for the lateral compartment and 7.3% (+0.034 N/mm²), 12.6% (+0.160 N/mm²), and 4.3% (+20.53 mm²) for the medial compartment, respectively.

Conclusion

Isolated DFO was inadequate to restore load distribution in meniscus-deficient knees, while concomitant LMAT restored near normal forces and improved the lateral compartment biomechanical profile.

Clinical Relevance

Our findings support the concomitant use of LMAT and varus-producing DFO in the setting of lateral meniscal deficiency with valgus malalignment. This study provides tools for the orthopaedic surgeon to individualize the correction for each patient.

Gradual Correction of Valgus Deformities of the Tibia Using a Monolateral External Fixator

Objective

To present a review of patients subjected to gradual correction of a valgus deformity of the tibia using a monolateral external fixator.

Method

This retrospective review included patients from January 2012 to May 2022 who met the following inclusion criteria: deviation of mechanical axis of the limb due to valgus deformity of the tibia; tibial deformity in the coronal plane on radiographic examination; a documented outpatient pre-operative evaluation by an orthopaedic surgeon and age between 10 and 70 years. The following exclusion criteria were applied: the presence of another tibia deformity preventing gradual correction using the proposed assembly; skin conditions incompatible with the surgical procedure; inadequate pre- or post-operative radiological evaluation; and insufficient information in the medical records.

Results

The mean age of patients with a valgus deformity of the tibia was 30.8 ± 15.9 years. These patients had a body mass index (BMI) of 26.1 ± 5.5 kg/m2. A congenital or developmental aetiology was attributed to 58.3% of the cases. Most commonly, the deformity was found in the middle third of the tibia with a mean deformity of 14.7 ± 6.6 degrees. The total external fixator time ranged from 73 to 229 days (average 149.7 ± 36.1 days). The mean medial proximal and lateral distal tibial angles differed significantly for pre- and post-operative measurements (p ≤ 0.05). There were complications in eight cases; five cases of pin site infections, two cases of medial cortical fracture and one case of peroneal nerve neuropraxia.

Conclusion

The proposed correction technique produces a satisfactory angular correction and with similar outcomes as described in the literature.

How to cite this article

Motta DP, Faria JLR, Couto A, et al. Gradual Correction of Valgus Deformities of the Tibia Using a Monolateral External Fixator. Strategies Trauma Limb Reconstr 2023;18(2):123-132.

Outcomes of Distal Femoral Osteotomy for Valgus Malalignment: A Systematic Review and Meta-analysis of Closing Wedge Versus Opening Wedge Techniques

BACKGROUND

Valgus knee deformity increases the risk for lateral articular chondral damage, contributing to earlier onset and accelerated progression of osteoarthritis. Distal femoral osteotomy (DFO) unloads the lateral joint compartment and can be performed using closing wedge (CW) or opening wedge (OW) techniques.

PURPOSE

To perform a systematic review and meta-analysis for patients with valgus knee deformity undergoing DFO to determine differences in patient-reported outcome measures (PROMs), complications, and survival rates, comparing CW versus OW DFO.

STUDY DESIGN

Systematic review, Level of evidence, 4.

METHODS

A literature review was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines utilizing PubMed, Cochrane Database, Ovid/MEDLINE, and Scopus. Inclusion criteria consisted of studies reporting outcomes in patients undergoing CW or OW DFO for the treatment of valgus knee deformities with symptomatic lateral compartment pathology with a minimum 2-year follow-up. PROMs and complications were analyzed using random-effects modeling to identify differences in outcomes as a function of surgical technique. Long-term survival data, defined as conversion to total knee arthroplasty, were analyzed using a multiple metaregression model as a function of individual study follow-up time points and surgical technique.

RESULTS

In total, we included 23 retrospective studies (n = 619 knees), of which 10 studies (n = 271 knees) reported outcomes after CW DFO and 13 studies (n = 348 knees) reported on OW DFO outcomes. Good to excellent clinical outcomes were reported in PROMs when compared with preoperative values with both techniques, while no significant differences between techniques were appreciated on functional Knee Society Scores and Tegner scores. No significant differences were appreciated in the incidence of complications reported in patients undergoing CW (20%) versus OW (33%) DFO (P = .432). Pain requiring hardware removal was the most commonly reported complication in both groups. The survival rate for CW DFO was 81.5% (mean follow-up, 8.8 ± 4.3 years) compared with 90.5% for OW DFO (mean follow-up, 4.5 ± 1.5 years). Multiple metaregression demonstrated that patient follow-up (P < .001) was significantly associated with knee survival, while surgical technique (P = .810) was not a predictor of clinical failure.

CONCLUSIONS

Both CW and OW DFO techniques were associated with good to excellent clinical outcomes with no significant differences in PROMs based on technique. Pain requiring hardware removal was the most common complication in both techniques, while long-term survivability was found to be a function of follow-up and not surgical technique. Technique selection should be based on shared patient-physician decision making with an emphasis on surgeon preference and technique familiarity.

Combination of external fixation using digital six-axis fixator and internal fixation to treat severe complex knee deformity

BACKGROUND

Severe knee valgus/varus or complex multiplanar deformities are common in clinic. If not corrected in time, cartilage wear will be aggravated and initiate the osteoarthritis due to lower limb malalignment. Internal fixation is unable to correct severe complex deformities, especially when combined with lower limb discrepancy (LLD). Based on the self-designed digital six-axis external fixator Q spatial fixator (QSF), which can correct complex multiplanar deformities without changing structures, accuracy of correction can be improved significantly.

METHODS

This retrospective study included 24 patients who suffered from complex knee deformity with LLD treated by QSF and internal fixation at our institution from January 2018 to February 2021. All patients had a closing wedge distal femoral osteotomy with internal fixation for immediate correction and high tibia osteotomy with QSF fixation for postoperative progressive correction. Data of correction prescriptions were computed by software from postoperative CT scans.

RESULTS

Mean discrepancy length of operative side was 2.39 ± 1.04 cm (range 0.9-4.4 cm) preoperatively. The mean difference of lower limb was 0.32 ± 0.13 cm (range 0.11-0.58 cm) postoperatively. The length of limb correction had significant difference (p < 0.05). The mean MAD and HKA decreased significantly (p < 0.05), and the mean MPTA and LDFA increased significantly (p < 0.05). There were significant increase (p < 0.05) in the AKSS-O, AKSS-F and Tegner Activity Score. The lower limb alignment was corrected (p < 0.05). The mean time of removing external fixator was 112.8 ± 17.9 days (range 83-147 days).

CONCLUSIONS

Complex knee deformity with LLD can be treated by six-axis external fixator with internal fixation without total knee arthroplasty. Lower limb malalignment and discrepancy can be corrected precisely and effectively by this approach.

Functional and Radiographic Results of Arthroscopy-Assisted Lateral Open-Wedge Distal Femur Osteotomy for Lateral Compartment Osteoarthritis with Valgus Knee

Treating lower extremity malalignment-related knee osteoarthritis, especially valgus alignment, is a challenge. A high revision rate was observed with patients who underwent unicompartmental knee arthroplasty, so distal femur osteotomy has regained its popularity. This research aimed to evaluate the radiographic and functional outcomes of arthroscopy-assisted lateral open-wedge distal femur osteotomy (LOWDFO) for patients with lateral compartment osteoarthritis and valgus knees with a minimum follow-up of 2 years. Our study retrospectively included isolated lateral osteoarthritis (Outerbridge grade 3 and grade 4) of the knee related to valgus alignment and a young age (<65 y/o) with the demand for a high-impact activity event. Preoperative and postoperative radiographic and functional outcomes were evaluated. Significant pre-operative and postoperative mechanical correction was observed with mechanical axis deviation (preop/postop: −28.77 ± 12.98/−9.45 ± 7.36, p < 0.001), hip-knee angle (preop/postop: 7.64 ± 3.62/2.68 ± 2.04, p < 0.001), and mechanical lateral distal femoral angle (mLDFA, preop/postop: 10.9 ± 4.14/5.66 ± 3.71, p < 0.001). The International Knee Documentation Committee (IKDC) score also showed improvement after the operation (preop/postop: 57.36 ± 11.98/79.02 ± 4.58, p = 0.002). In conclusion, lateral open-wedge distal femur osteotomy is effective in treating patients with lateral compartment osteoarthritis and valgus knees with a low complication rate and excellent outcome.

Soft tissue stabilization of the hinge position in medial closed wedge distal femoral osteotomy: an anatomical study

BACKGROUND

Soft tissue has an important role in stabilizing the hinge point of medial closed wedge distal femoral osteotomy (MCWDFO). However, there are conflicting data on the soft tissue anatomy around the hinge point of MCWDFO and, therefore, further anatomical data are needed. The purposes of the study were to: 1) anatomically analyze the soft tissue around the hinge point of MCWDFO; 2) radiologically define the appropriate hinge point to prevent an unstable hinge fracture based on the result of the anatomical analysis; and 3) histologically analyze the soft tissue based on the result of the anatomical analysis.

METHODS

In 20 cadaveric knees, the capsule attachment of the distal lateral side of the femur was marked with a radiopaque ball bearing. A digital planning tool was used to calculate the area of the marked capsule attachment around the ideal hinge point of MCWDFO on radiographs. The soft tissue around the hinge point was histologically examined and the periosteal thickness was measured and visualized graphically. The graph and radiograph were overlayed using image editing software, and the appropriate hinge position was determined based on the periosteal thickness.

RESULTS

As a result, the periosteal thickness of the distal lateral femur tended to rapidly decrease from the metaphyseal region toward the diaphyseal region. The overlayed graph and radiograph revealed that the periosteal thickness changed in the region corresponding to the apex of the turning point of the femoral metaphysis in all cases.

CONCLUSIONS

In conclusion, the periosteum might support the hinge of MCWDFO within the area surrounded by the apex of the turning point of the femoral metaphysis and the upper border of the posterior part of the lateral femoral condyle.

Predictive Factors for Lateral Hinge Fracture in Medial Closing Wedge Distal Femoral Osteotomy

BACKGROUND

Recent studies have reported that lateral hinge fracture (LHF) has a negative effect on bone healing at the osteotomy site after medial closing wedge distal femoral osteotomy (MCDFO). However, limited evidence exists in the literature regarding the predictive factors for LHF in MCDFO.

HYPOTHESIS

A large medial closing gap and a lateral hinge position in the supracondylar area would increase plain radiography-based and/or computed tomography (CT)-based LHF in MCDFO.

STUDY DESIGN

Case control study; Level of evidence, 3.

METHODS

We retrospectively evaluated 67 knees of 53 patients (mean age, 37.4 ± 16.9 years) who underwent MCDFO between May 2009 and June 2021. The surgical indications for MCDFO were genu valgum deformity combined with either lateral compartment osteoarthritis or recurrent patellar dislocation. The presence of LHF was evaluated based on immediate postoperative plain radiography and CT scans. The predictive factors for LHF in MCDFO were investigated using multivariate logistic regression analysis.

RESULTS

LHFs were identified in 21 knees (31.3%) through plain radiography and in 40 knees (59.7%) through CT. Multivariate logistic regression analysis showed that the medial closing gap and lateral hinge position were predictive factors for plain radiography- and CT-based LHF after MCDFO. Controlling for other variables, we found that an increase in the medial opening gap by 1 mm increased the likelihood of plain radiography-based LHF by a factor of 1.805 (95% CI, 1.291-2.525; P = .001) and CT-based LHF by 1.333 (95% CI, 1.003-1.772; P = .048). Moreover, a lateral hinge position in the supracondylar area increased the likelihood of plain radiography-based LHF by a factor of 9.870 (95% CI, 2.179-44.720; P = .003) and CT-based LHF by 5.686 (95% CI, 1.124-28.754; P = .036).

CONCLUSION

A large medial closing gap and lateral hinge position in the supracondylar area are associated with LHF in MCDFO. Care should be taken to prevent LHF in MCDFO with a large medial closing gap. Moreover, a lateral hinge position in the supracondylar area should be avoided to decrease the incidence of LHF in MCDFO.

Complications after high tibial osteotomy and distal femoral osteotomy are associated with increasing medical comorbidities and tobacco use

PURPOSE

The purpose of this study was to assess complications, reoperations, and their risk factors at 90 days and 2 years after high tibial osteotomy (HTO) and distal femoral osteotomy (DFO) in a national cohort.

METHODS

The PearlDiver Mariner Dataset was queried using International Classification of Diseases (ICD) and Current Procedural Terminology (CPT) codes for HTO and DFO, complications, and subsequent surgery. Minimum follow-up was 2 years and complications were assessed at 90 days and 2 years. Hospital readmission in the first 90 days was also assessed. Univariate and multiple logistic regression were utilized to identify risk factors for complications and re-operation.

RESULTS

The 90-day and 2-year complication rates after HTO (n = 1780) were 11.6% and 31.7%, compared to 21.5% (p < 0.0001) and 41.5% (p = 0.0001) after DFO (n = 446). Infection was the most frequent early (90-day) complication for both HTO and DFO cohorts, while hardware problems were most common at 2 years. Increasing Elixhauser Comorbidity Index (ECI) was associated with increased odds of infection, readmission, and hardware-associated complications in both cohorts. Gender and tobacco use were also associated with various complications after HTO. At 2 years, 23.7% of HTO patients and 26.2% of DFO patients had undergone subsequent surgery. Hardware removal occurred in 16.4% of HTO and 18.4% of DFO patients (n.s.), while 4.5% of HTO and 5.2% of DFO patients underwent total knee arthroplasty (TKA) within 2 years (n.s.).

CONCLUSION

HTO and DFO have substantial complication rates in the short and mid term, with a higher rate of overall complications observed after DFO as compared to the HTO cohort. After both procedures, roughly one quarter of patients will undergo subsequent surgery within 2 years. Patients with tobacco use and numerous medical co-morbidities may not be optimal candidates due to increased complication rates. Elixhauser Comorbidity Index (ECI) may be an useful tool for risk assessment prior to surgery.

LEVEL OF EVIDENCE

Retrospective cohort study, III.

Computer-aided Design of Distal Femoral Osteotomy for the Valgus Knee and Effect of Correction Angle on Joint Loading by Finite Element Analysis

Objective

Lateral open‐wedge distal femoral osteotomy (DFO) has been used to treat valgus deformity of the knee, with good clinical outcomes. However, there is a lack of biomechanical studies regarding the angle of correction. The objective of this study was to apply computer‐aided design (CAD) for osteotomy planning in a three‐dimensional (3D) anatomical model and to assess the biomechanical differences among the varying correction angles on joint loading by finite element analysis (FEA).

Methods

To model different angles of lateral open‐wedge DFO correction, the CAD software package Mimics 21.0 was used to accurately simulate the operated knee. The femur was cut to 0°, 2°, 4°, 6°, 8°, and 10° of varus (equivalent to hip‐knee‐ankle angles of 180°, 178°, 176°, 174°, 172°, and 170°, respectively). The original knee model and the corrected models were processed by FE software. Then, the FE models were subjected to an axial force to obtain the von Mises stress (VMS) and shear stress distributions within the femoral cartilages and menisci.

Results

Under a compressive load of 740 N, the highest VMS in lateral and medial compartments of the intact knee model was 3.418 and 3.303 MPa. The maximum value of both the VMS and the shear stress in the lateral compartment decreased as the varus angle increased, but the corresponding values in the medial compartment increased. When the hip‐knee‐ankle (HKA) angle was 180°, the VMS in the lateral and medial compartments was balanced (3.418 and 3.303 MPa, respectively). Meanwhile, when the HKA angle was 178° (3.488 and 3.625 MPa, respectively), the shear stress in the lateral and medial compartments was balanced. In addition, the magnitude of change in the stress was significantly higher in the medial compartment (90.9%) than in the lateral compartment (19.3%).

Conclusion

The optimal correction angle of the valgus knee is close to neutral alignment or slightly varus (0° ‐ 2°). Overcorrection is not recommended, as it can result in a steep increase of the stress within the medial compartment and may accelerate the process of medial compartment OA.

Isolated Lateral Tibiofemoral Compartment Osteoarthritis: Survivorship and Patient Acceptable Symptom State After Lateral Fixed-Bearing Unicompartmental Knee Arthroplasty at Mean 10-Year Follow-up

BACKGROUND

Lateral unicompartmental knee arthroplasty (UKA) is an excellent option to alleviate disability and restore function in patients with lateral compartment knee osteoarthritis (OA). The purpose of the present study was to determine the survivorship and long-term outcomes in both younger/middle-aged and older patients with lateral compartment OA following non-robotically-assisted, fixed-bearing lateral UKA and to determine if an acceptable symptom state can be achieved.

METHODS

All patients were managed with fixed-bearing lateral UKA by a single surgeon utilizing a lateral parapatellar approach without robotic assistance. The primary outcome variables were the Knee injury and Osteoarthritis Outcome Score (KOOS) Activities of Daily Living (ADL) and Sport subscale scores. In addition, the other KOOS subscores, the Lysholm score, the achievement of the Patient Acceptable Symptom State (PASS), and the Veterans RAND (VR-12) Physical Component Summary score (PCS) and Mental Component Summary score (MCS) were collected. Failure was defined as conversion to total knee arthroplasty (TKA). Patients were divided into 2 cohorts: younger/middle-aged patients (<60 years of age) and older patients (≥60 years of age).

RESULTS

A cohort of 256 patients underwent medial (n = 193) or lateral (n = 63) UKA. Sixty-one patients met the inclusion criteria. At mean of 10 years (range, 4 to 17 years) of follow-up, there were no significant differences between the groups in terms of any patient-reported outcome measures (p > 0.05). The percentage of patients in whom PASS was achieved on the KOOS ADL and Sport subscores was 82% and 88%, respectively, in the younger cohort and 80% and 80%, respectively, in the older cohort. The mean survival estimate of the prothesis was 15.3 years (95% confidence interval [CI], 14.5 to 16.2 years) for the entire cohort. The estimated rate of implant survival in the younger cohort was 100% at 5 and 10 years, and the estimated rate of implant survival in the older cohort was 98% at 5 years and 96% at 10 years.

CONCLUSIONS

Lateral fixed-bearing, non-robotic UKA for the treatment of isolated lateral compartment OA resulted in >80% of patients reaching an acceptable symptom state in terms of both activities of daily living and sporting activities. UKA provides an excellent option that provides longevity with high PASS rates and return to activities with a low risk of complications and failure.

LEVEL OF EVIDENCE

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

Analysis of bone union after medial closing wedge distal femoral osteotomy using a new radiographic scoring system

INTRODUCTION

To compare bone union after medial closing wedge distal femoral osteotomy (MCWDFO) with that after lateral closing wedge distal femoral osteotomy (LCWDFO) using a novel scoring system.

MATERIALS AND METHODS

The data of 30 patients who received biplanar MCWDFO for valgus knees (MCWDFO group) were retrospectively examined and compared to that of 22 patients (25 knees) who underwent biplanar LCWDFO via a double-level osteotomy (DLO) for varus knees (LCWDFO group). The progression of bone union of the transverse osteotomy plane in the femur was assessed using a newly developed scoring system using radiographs taken immediately after surgery and 3 and 6 months postoperatively. The scoring system is based on a scale of zero to six points with higher scores indicating better bone union. The incidence of hinge fractures was assessed using CT images, and the rates of reoperation were evaluated using medical record data.

RESULTS

The mean bone union score was significantly lower in the MCWDFO group than in the LCWDFO group 3 months (2.1 ± 1.9 vs. 3.7 ± 1.7, P < 0.01) and 6 months (3.8 ± 2.1 vs 4.9 ± 1.5, P < 0.05) postoperatively. The incidence ratio of hinge fractures was significantly higher in the MCWDFO group than in the LCWDFO group (70.0% vs. 32.0%, P < 0.01). Two patients in the MCWDFO group underwent reoperation for delayed bone union or non-union.

CONCLUSION

Bone union progression was slower and hinge fractures were more frequently observed after MCWDFO than after LCWDFO via DLO. MCWDFO is technically challenging, and patients must be monitored closely during and after surgery.

Improved Accuracy of Coronal Alignment Can Be Attained Using 3D-Printed Patient-Specific Instrumentation for Knee Osteotomies: A Systematic Review of Level III and IV Studies

PURPOSE

To evaluate the accuracy and precision of postoperative coronal plane alignment using 3D-printed patient-specific instrumentation (PSI) in the setting of proximal tibial or distal femoral osteotomies.

METHODS

A systematic review evaluating the accuracy of 3D-printed PSI for coronal plane alignment correcting knee osteotomies was performed. The primary outcomes were accuracy of coronal plane limb alignment correction and number of correction outliers. Secondary variables were duration of surgery, number of intraoperative fluoroscopic images, complications, cost, and clinical outcomes (as applicable).

RESULTS

Ninety-three studies were identified, and 14 were included in the final analysis. Overall, mean postoperative deviation from target correction ranged from 0.3° to 1° for all studies using hip-knee angle measurements and 2.3% to 4.9% for all studies using weight-bearing line measurements. The incidence of correction outliers was assessed in 8 total studies and ranged from 0 to 25% (total n = 10 knees) of patients corrected with 3D-printed PSI. Osteotomies performed with 3D-printed cutting guides or wedges demonstrated significantly shorter operative times (P < .05) and fewer intraoperative fluoroscopic images (P < .05) than control groups in four case control studies.

CONCLUSION

Patients undergoing distal femoral osteotomy or proximal tibial osteotomy procedures with 3D-printed patient-specific cutting guides and wedges had highly accurate coronal plane alignment with a low rate of outliers. Patients treated with 3D printed PSI also demonstrated significantly shorter operative times and decreased intraoperative fluoroscopy when compared to conventional techniques.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III-IV studies.

Return to Sport and Work Following Distal Femoral Varus Osteotomy: A Systematic Review

Background: Distal femoral varus osteotomy (DFVO) is an effective surgical intervention for the management of symptomatic valgus malalignment of the knee. Because it preserves the native knee joint and its ligamentous stability, DFVO is preferred to total knee arthroplasty (TKA) in the young, active population. Purpose: We sought to assess return to work (RTW) and return to sport (RTS) rates following DFVO for valgus malalignment of the knee. Methods: For this systematic review, we searched EMBASE, MEDLINE, and Web of Science from inception through December 31, 2020. English language studies of all levels of evidence explicitly reporting on RTS and RTW rates following DFVO for valgus malalignment of the knee were eligible for inclusion. Results: Seven studies and 127 patients were included in our analysis. Mean age was 32.4 ± 8.8 years with men comprising 46.7% ± 22.3% of study populations. The mean RTS rate was 87.2% ± 10.7%, with a return to preoperative activity levels rate of 65.4% ± 26.8%. The mean RTW rate was 81.8% ± 23.3%, with a return to preoperative activity levels of 72.8% ± 18.1%. The mean reoperation rate was 35.6% ± 18.8% within a mean follow-up period of 5.5 ± 1.9 years. Conclusions: This systematic review of low-level studies found DFVO to be a safe and effective procedure for the management of genu valgum in young, active populations, with most patients returning to sport and/or work, although not all at their preoperative activity levels. A paucity of data surrounds RTS and RTW rates following DFVO. Future studies should explicitly report both return to activity rates and whether patients returned to their preoperative activity levels.

Return to sport following distal femur osteotomy: a systematic review

INTRODUCTION

Distal femur osteotomies (DFOs) are well-accepted procedures in treating unicompartmental knee osteoarthritis associated with valgus malalignment. This study aims to investigate the Return to sport (RTS) after DFO.

MATERIALS AND METHODS

We conducted a systematic review of the literature according to the PRISMA guidelines, including all articles published in English, with no time limit, excluding double-level knee osteotomies.

RESULTS

Five articles were included for an overall cohort of 76 patients. The mean follow-up was 45.53 months. The mean age of the patients at the time of surgery was 33.87 years, and the mean malalignment was 5.59° in valgus. In 70 cases, patients received a lateral DFO, while in 6 cases, a medial closing-wedge DFO. An RTS of 86.1% was observed after DFO and a mean time to RTS of 12.3 months. 76.8% of patients recovered to a level equal to or higher than that practiced before the onset of symptoms. No statistically significant differences were observed in the RTS rate between those who performed lateral or medial DFO.

CONCLUSIONS

RTS after DFO is ubiquitous and occurs around one year after surgery. In most cases, patients report improved performance compared to what they experienced before the onset of symptoms. Unfortunately, while athletes often have RTS at a similar or better level, other patients often see a return to lower impact sports.

Vascular Complications in Sports Surgery: Diagnosis and Management

Orthopedic sports surgery of the knee and shoulder is generally considered to be safe and effective. Vascular complications can occur during or after arthroscopy of either joint. A thorough understanding of anatomy, particularly when placing portals in non-routine locations, is extremely important. Prompt recognition of any vascular complication is of significant importance. This review will discuss the potential vascular complications for both knee and shoulder sports surgery, review the relevant anatomy, and discuss the treatment and expected outcome of each.

[Research progress of osteotomy around knee in the treatment of valgus knee osteoarthritis]

OBJECTIVE

To review the research progress of surgical methods of osteotomy around the knee in the treatment of valgus knee osteoarthritis.

METHODS

The relevant literature on the surgical treatment of valgus knee osteoarthritis at home and abroad in recent years was reviewed, and the advantages, disadvantages, and effectiveness of different surgical methods of osteotomy around the knee were summarized.

RESULTS

For young and active patients with symptomatic valgus knee osteoarthritis, osteotomy around the knee is a safe and reliable treatment option. At present, the main surgical methods include medial closing wedge distal femoral osteotomy, lateral opening wedge distal femoral osteotomy, medial closing wedge high tibial osteotomy, and lateral opening wedge high tibial osteotomy. The indications, advantages, and disadvantages of different osteotomies are different, and the selection of appropriate surgical method is the key to achieve good effectiveness.

CONCLUSION

There are many osteotomies in the treatment of valgus knee osteoarthritis. In order to achieve good results, improve survival rate, and reduce postoperative complications, the most reasonable surgical strategy needs to be developed according to different situations.

Osteotomies for lateral compartment knee osteoarthritis

Lateral compartment osteoarthritis (LCOA) is often associated with valgus deformity of the knee. The concept of correcting the alignment by performing distal femoral varus osteotomy (DFVO) to unload the lateral compartment is well accepted and it is viewed as the preferred option for young active patients due to dissatisfaction from arthroplasty under 55 years of age or if they wish to remain active. Beyond this there is no consensus on patient selection, preoperative assessment, techniques to achieve correction, end point of correction, return to work or sports post-surgery, and survivorship of osteotomy with conversion to a total knee replacement as the end point due to heterogenous, retrospective studies. Here, we review relevant literature to help patient selection, preoperative work up, techniques, and outcomes.

Return to Sport following Isolated Lateral Opening Wedge Distal Femoral Osteotomy

Purpose. The aims of this study were to (1) examine the timeline of return to sport (RTS) following isolated lateral opening wedge distal femoral osteotomy (DFO), (2) evaluate the degree of participation on RTS, and (3) identify risk factors for failure to RTS. Methods. Nineteen consecutive patients undergoing isolated lateral opening wedge DFO were reviewed retrospectively at a minimum of 2 years postoperatively. Patients completed a sports questionnaire, visual analogue scale for pain (VAS-Pain), Single Assessment Numerical Evaluation (SANE), and a satisfaction questionnaire. Results. Seventeen patents (89.5%; age 32.1 ± 10.1 years; gender 9 males, 52.9%) were contacted at 7.3 ± 4.4 years (range 2.0-13.8 years). Twelve patients (70.6%) resumed playing ≥1 sport at an average time of 9.5 ± 3.3 months (range 3-12 months). Of these 12 patients, 6 returned to a lower level of participation (50.0%). Seven patients (41.2%) had returned to the operating room for further surgery, which included removal of hardware (5.9%) and total knee arthroplasty (5.9%). The average VAS-Pain, SANE, and Marx scores were 3.4 ± 2.6 (range 0-8), 56.2 ± 18.7 (range 20-85), and 5.0 ± 5.3 (range 0-16), respectively. Fourteen patients (82.4%) were at least somewhat satisfied with their procedure. Conclusion. In patients with isolated lateral compartment osteoarthritis and valgus deformity, lateral opening wedge DFO allows 70.6% of patients to RTS by 9.5 ± 3.3 months. However, most patients may be unable to return to their presymptomatic level of function. Patient expectations regarding RTS can be appropriately managed with adequate preoperative patient education. Level of Evidence. IV, case series.

Change of limb alignment in Korean children and adolescents with idiopathic genu valgum

There has been no study evaluating the change of limb alignment for patients with genu valgum. The purpose of this study was to investigate the change of limb alignments in children and adolescents with idiopathic genu valgum through evaluating distal femur, proximal tibia, and knee joint line.Consecutive children and adolescents, under the age of 18, with genu valgum were included. Mechanical tibiofemoral angle, mechanical lateral distal femoral angle, mechanical medial proximal tibia angle, and joint line convergence angle were measured. The rate of changes for each radiographic measurement were analyzed using a linear mixed model.A total of 1539 teleroentgenograms from 518 limbs of 273 individuals were included in this study. Linear mixed model showed that the change of limb alignment was significantly associated with age, but not associated with gender and laterality. The mechanical tibiofemoral angle was most valgus initially, decreasing until reaching its lowest value of 2.8° at 10 years old. The mechanical lateral distal femoral angle decreases from initial neutral alignment and increases in valgus continuously. The mechanical medial proximal tibia angle decreases from initial valgus and progresses to be neutral at around the age of 10. The joint line convergence angle decreases sharply from initial valgus alignment to 0° at the age of 5.Valgus alignment in children with idiopathic genu valgum decreases until approximately the age of 10. In younger children, the tibia and joint line contribute most to overall valgus alignment; in older children, the femur contributes the most. Based on our results, we recommend monitoring patient limb alignment until it stabilizes around the age of 10, and then carefully planning and performing corrective surgery with complete consideration of the changing bony alignment.

Patient-Specific Instrument Guided Double Chevron-Cut Distal Femur Osteotomy

The risk of non-union and prolonged periods of protected weight-bearing still remain unsolved issues after distal femur osteotomy (DFO). To improve the stability, we developed the double chevron-cut technique, which is a modified medial closing-wedge DFO guided by a patient-specific instrument. The purpose of this study was to investigate the feasibility and outcome of this operative approach. Twenty-five knees in twenty-three consecutive patients with genu valgum and lateral compartment osteoarthritis that received double chevron-cut DFO were included. The target of correction was 50% on the weight-bearing line (WBL) ratio. Patient-reported outcomes included the Oxford Knee Score (OKS) and the 2011 Knee Society Score (KSS). The mean of the WBL ratio was corrected from 78.7% ± 12.0% to 48.7% ± 2.9% postoperatively. The mean time to full weight bearing was 3.7 ± 1.4 weeks. Union of the osteotomy was achieved at 11.3 ± 2.8 weeks. At a mean follow-up of 17 months, the OKS improved from a mean of 27.6 ± 11.7 to 39.1 ± 7.5 (p = 0.03), and the KSS from a mean of 92.1 ± 13.0 to 143.9 ± 10.2 (p < 0.001). Three patients developed complications, including one case of peri-implant fracture, one of loss of fixation, and one of non-union. The double chevron-cut DFO followed by immediate weight-bearing as tolerated is effective in treating genu valgum deformity and associated lateral compartment osteoarthritis.

Patient-Reported Outcomes for Large Bipolar Osteochondral Allograft Transplantation in Combination with Realignment Osteotomies for the Knee

Effective treatment for bipolar articular cartilage lesions in the knee remains a clinical challenge. Lower extremity malalignment is a risk factor for treatment failures, which can be addressed by tibial or femoral osteotomy. The purpose of this study was to compare outcomes among patients who underwent knee joint restoration by osteochondral allograft (OCA) transplantation with concurrent or staged realignment osteotomy. With Institutional Review Board approval, patients undergoing bipolar OCA transplantation with concurrent or staged distal femoral osteotomy (DFO) or high tibial osteotomy (HTO) were analyzed. Patients were categorized by osteotomy type (DFO and HTO) and timing (concurrent and staged). Patient-reported outcome measures (PROMs), revisions, failures, and complications were examined preoperatively (baseline), 3, 6, 12, and 24 months after OCA transplantation; change scores from preoperative values were used for analysis. A total of 23 patients met inclusion criteria (15 males); 13 (56.5%) received HTO (5 concurrent), while 10 (43.5%) received DFO (5 concurrent). There were no significant differences in complication rates between concurrent and staged osteotomies. Primary bipolar OCA transplantation with osteotomy was associated with successful outcomes in 70% of patients; four patients underwent revision (17.4%) and three (13.0%) failed and were treated by total knee arthroplasty. Further, the four patients undergoing revision met functional criteria for success at final follow-up, resulting in a 2-year functional survival rate of 87.4%. Aside from Patient-Reported Outcomes Measurement Information System (PROMIS) physical function, all PROMs for concurrent and staged osteotomies improved from baseline to 2 years postoperatively. Concurrent osteotomies of both types were associated with significantly lower pain scores at 12 months (p = 0.04), compared with staged osteotomies. Apart from Single Assessment Numerical Evaluation (SANE), more PROM improvement was observed for concurrent osteotomies at 2 years. Improvements in PROMs for patients undergoing OCA transplantation combined with osteotomy were observed at 2-year follow-up. PROMs for concurrent osteotomy were consistently greater than staged osteotomy, lending support to addressing lower extremity malalignment with bipolar OCA transplantation in the knee during a single surgery when possible.

Contemporary Knee Osteotomy in the United States: High Tibial Osteotomy and Distal Femoral Osteotomy Have Comparable Complication Rates despite Differing Demographic Profiles

Knee osteotomies show efficacy in slowing knee osteoarthritis progression and delaying the need for total knee arthroplasty in younger patients. Despite evolutions in indications, techniques, and hardware that have improved outcomes, longitudinal trends demonstrate a decline in high tibial osteotomy (HTO) and distal femoral osteotomy (DFO) use. Unfortunately, knowledge of the current usage and complications associated with HTO and DFO is limited. The purpose of this study was to compare the preoperative demographics and early complication rates of HTO and DFO. We analyzed the HTOs and DFOs performed between 2006 and 2017 using the ACS-NSQIP (American College of Surgeons National Surgical Quality Improvement Program) database. We compared both groups for preoperative patient demographics (sex, age, race, body mass index [BMI]) and health status variables including functional scores, ASA (American Society of Anesthesiologists) scores, smoking status, and other comorbidities. Emergency and elective status of the patient case, length of hospital stay, operation time, and 30-day postoperative complications were also analyzed. After the exclusion criteria were applied, 321 HTO and 295 DFO patients were included in the final analysis. The HTO group had higher proportions of younger (p < 0.001) and male (p < 0.001) patients with higher BMI (p = 0.007). Racial profiles were similar between the two groups (p = 0.575). Preoperatively, those in the HTO group had more functional independence, better physical status scores, and fewer chronic conditions (p < 0.05). There were no statistically significant differences between HTO and DFO in operative time, postoperative complications, readmission, and reoperation. HTO patients, however, had shorter hospital stays (p < 0.001). Although there are differences in preoperative and operative characteristics of HTO and DFO, early postoperative complications are similar for both groups. Therefore, HTO and DFO can be considered safe and effective treatment options for younger patients with symptomatic unicompartmental knee osteoarthritis.

Ten-year survival rate of 89% after distal femoral osteotomy surgery for lateral compartment osteoarthritis of the knee

PURPOSE

The purpose of this study was to assess the accuracy, safety, and survival of distal femoral osteotomy (DFO) surgery for lateral compartment OA of the knee.

METHODS

A retrospective cohort study was conducted at a single UK centre, using prospectively collected data over an 8-year period (2009-2017). All patients had pre-operative radiographic analysis and digital planning of their deformity correction in addition to post-operative analysis of the achieved correction and yearly face-to-face follow-up. Complications (defined as an undesirable medical or surgical event as a direct result of the operation), reoperations, and failure (defined as conversion to arthroplasty or revision) were recorded.

RESULTS

From a total of 83 patients, 81 patients undergoing 86 primary DFOs were included in this study, with a mean follow-up of 99 months (SD 27 months). The mean pre-operative percentage Mikulicz point was 78.7% (SD 19.1%) and post-operative 35.9% (SD 14.8%). The mean accuracy of correction (intended correction - achieved correction) was an 8.2% overcorrection (SD 13.7%). The complication rate was 4.7%. Using Kaplan-Meier analysis, the mean survival was 113 months (95% CI 106-120) with the probability of surviving 10 years 89%.

CONCLUSION

DFO for valgus alignment and lateral compartment arthritis is associated with low complications, long-term joint preservation, and the prevention of arthroplasty surgery. However, the accuracy of correction still requires improvement in intra-operative technique.

LEVEL OF EVIDENCE

IV.

Medial Biplanar Closing-Wedge Distal Femoral Osteotomy Using an Articulated Tensioning Device for Controlled Osteotomy Closure

Isolated lateral compartment arthritis or focal chondral defects in the setting of genu valgum in young, active individuals can be treated with a varus-producing distal femoral osteotomy with or without cartilage treatment. Both medial closing-wedge and lateral opening-wedge techniques have been described, with neither demonstrating clear superiority. The objective of this Technical Note is to describe a technique of biplanar medial opening-wedge with controlled reduction using an articulated tensioning device to achieve a safe, reproducible result.

Return to Work After Distal Femoral Varus Osteotomy

Background

Distal femoral varus osteotomy (DFVO) is a well-described procedure to address valgus deformity of the knee. There is a paucity of information available regarding patients' ability to return to work (RTW) after DFVO.

Purpose

To report the objective findings for RTW rates and times for patients receiving a DFVO for lateral compartment osteoarthritis secondary to valgus deformity of the knee.

Study Design

Cohort study; Level of evidence, 3.

Methods

This was a retrospective study of patients who received a lateral-wedge opening DFVO. Patients must have worked within 3 years before their operation to be included for analysis. Patients were contacted at a minimum of 2 years postoperatively for interview and questionnaire evaluation, including a subjective work questionnaire, visual analog scale (VAS) for pain, Single Assessment Numerical Evaluation (SANE), and a satisfaction questionnaire.

Results

Overall, 32 patients were contacted at a mean follow-up of 7.1 ± 4.1 years (range, 2.2-13.3 years). The mean ± SD age at the time of surgery was 30.8 ± 8.8 years (range, 17.2-46.5 years), and 65.6% of patients were female. Eleven patients (34.4%) received a concomitant meniscal allograft transplant, and 12 (37.5%) received a cartilage grafting procedure. The average VAS pain score decreased significantly from 6.1 preoperatively to 3.2 postoperatively (P = .03). All patients were able to RTW, at a mean time of 6.0 ± 13.2 months postoperatively (range, 0-72 months). When stratified by work intensity, the average time to return was 13.8, 3.1, 2.7, and 2.9 months for high, moderate, light, and sedentary occupations, respectively. There was no significant difference between these RTW times (P = .16), although this analysis may have been limited by the small sample size. Four patients whose work was classified as heavy work (50%) and 3 whose work was classified as moderate work (18.8%) either switched jobs or kept the same job with lighter physical duties as a result of their procedures.

Conclusion

In a young and active population, DFVO for valgus deformity reliably afforded the ability to RTW within a relatively short time for patients with sedentary, light, and moderate occupational demands. However, patients with moderate- to high-intensity occupational demands may be unable to RTW at their preoperative level.

Factors affecting the disparity between preoperative planning and postoperative correction status in distal femoral osteotomy

BACKGROUND

The purposes of this study were to evaluate whether the planning method using the contralateral limb status is reasonable and to determine the disparity between the preoperative planning and actual postoperative correction status by analyzing lateral cortical hinge fractures (LCHFs) in patients who underwent distal femoral osteotomy (DFO).

METHODS

From 2014 to 2018, 31 cases undergoing DFO were evaluated. The patients were divided into two groups according to two preoperative planning methods. The disparity between the preoperative planning and the postoperative weight-bearing line (WBL) ratio and clinical scores were compared. Analysis was performed to determine the causes of the disparity by evaluating the osteotomy configuration, including that of LCHFs.

RESULTS

The disparity was observed in the WBL ratio assessment (P < 0.01). In the comparison between two groups, no statistically significant differences were found in the change of WBL ratio (P = 0.78) and postoperative clinical scores. The length of the osteotomy gap was only related to the disparity (R² = 0.22, P = 0.01), while no statistical significance was found for the regression equation of the displaced LCHF (P > 0.05). The length of the remaining bone between the osteotomy end and opposite cortex was significantly associated with the presence of LCHF (odds ratio, 3.904).

CONCLUSIONS

The planning method using a contralateral limb status showed similar results to the classical method, but the two methods produced disparity when the degree of correction was increased. LCHF was mostly related to the remaining bone in the medial closing-wedge DFO.

Technique for Biplanar Lateral Opening Wedge Distal Femoral Osteotomy in the Valgus Knee

Valgus malalignment can be corrected with a biplanar lateral opening wedge distal femoral osteotomy (bLOWDFO) in patients with symptomatic lateral compartment disease. Advantages of a lateral opening wedge technique over the medial closing wedge technique include avoidance of vascular structures and theoretically better control of the amount of correction. The advantages of a bLOWDFO over a uniplanar osteotomy are that it creates a larger surface area for healing, and provides inherent stability to control the osteotomy intraoperatively. The purpose of this article is to present a reproducible technique for bLOWDFO and review the indications, preoperative planning, rationale, and clinical outcomes.

Preliminary Evaluation of the Efficacy of Postoperative Early Weight-bearing Rehabilitation Protocol for Patients after Double-level Osteotomy

Objective:

There are no reports describing in detail postoperative rehabilitation after double-level osteotomy (DLO). Consequently, the establishment of a safe and effective rehabilitation protocol is required.

Methods:

This retrospective study included 26 patients with varus knees who underwent DLO. No patient had obvious fracture around the femoral osteotomy sites, as evaluated using computed tomography (CT) 3 weeks postoperatively. From 3 days postoperatively, gait training with early weight bearing was performed using our parallel bar protocol. Range of motion exercises were permitted as tolerated. Radiological evaluation was performed to confirm the presence or absence of fracture around the femoral osteotomy sites using CT at 3 weeks and X-ray at 6 weeks postoperatively. X-ray imaging 6 months postoperatively indicated no femoral correction loss. Additionally, the time from initiation to completion of the protocol and the time from initiation to achievement of independent gait were recorded.

Results:

No fractures around the femoral osteotomy sites in any patient were found using CT 3 weeks postoperatively and X-rays 6 weeks postoperatively. There was no correction loss at the femoral osteotomy site according to X-ray findings 6 months postoperatively. The mean time until completion of the parallel bar protocol was 19.8 ± 6.2 (7–30) days, and that from the initiation of rehabilitation to the achievement of independent gait was 26.8 ± 7.1 (16–45) days.

Conclusion:

Patients without fracture around the femoral osteotomy site during the rehabilitation period could achieve independent gait within an average of <1 month using the parallel bar protocol. Early weight-bearing walking and independent walking could be achieved using this protocol.

The effect of patellar facet angle on patellofemoral alignment and arthritis progression in posterior-stabilized total knee arthroplasty without patellar resurfacing

Background

The purpose of this study was to evaluate the effect of patellar facet angle on pre- and postoperative patellofemoral alignment and the progress of arthritis of the patellofemoral joint in posterior-stabilized total knee arthroplasty (PS TKA) without patellar resurfacing.

Methods

Patients who had a PS TKA for a varus osteoarthritic knee who were followed up for more than 2 years were included in this study. The radiologic and clinical outcomes were compared between 72 knees (group A) whose patellar facet angle was greater than 126° (> 126°) and 32 knees (group B) whose patellar facet angle was smaller than or equal to 126° (≤ 126°). For the radiologic assessment, the Kellgren-Lawrence grade, mechanical femorotibial angle, Insall-Salvati ratio, patellar tilt angle, patellar displacement and the osteosclerosis of the patellar ridge were evaluated. The range of motion (ROM) and patient-reported outcomes (the Knee Society knee score, the Knee Society function score, the Feller patellar score, and the Kujala patellofemoral score) were used for the clinical assessment.

Results

The preoperative patellar tilt angle was 9.8° (standard deviation [SD] 5.5) and 14.6° (SD 4.1) in group A and group B, respectively, a significant difference (p < 0.001). Other preoperative radiologic parameters and preoperative patient-reported outcomes and ROM showed no significant difference between the two groups (all parameters (p > 0.05). At the last-follow-up, 22 knees (30.6%) showed progression of osteosclerosis of the patellar ridge in group A and 13 knees (40.6%) showed progression of osteosclerosis in group B (p = 0.371). The postoperative radiologic and clinical outcomes showed no significant difference between the two groups (all parameters, p > 0.05).

Conclusions

Although a narrow patellar facet angle was related to an increase of lateral tilting of the patella, it showed no impact on the preoperative clinical assessment. The radiologic and clinical outcomes evaluated after the PS TKA showed no statistical difference according to the patellar shape. Although the patellar shape evaluated by the patellar facet angle can partially affect the preoperative patellofemoral alignment, this study result indicated insignificant clinical relevance of the patellar shape in the PS TKA.

Return to Sport and Outcomes After Concomitant Lateral Meniscal Allograft Transplant and Distal Femoral Varus Osteotomy

PURPOSE

To evaluate the time and rate of return to sport (RTS), as well as outcomes, in young and active patients receiving concomitant lateral meniscal allograft transplantation (MAT) and distal femoral varus osteotomy (DFVO) for lateral meniscal deficiency and valgus malalignment.

METHODS

This was a retrospective study of consecutive patients who underwent concomitant MAT and DFVO by a single surgeon. The exclusion criteria were any concomitant procedures other than cartilage restoration procedures for focal full-thickness cartilage defects of the lateral femoral condyle and less than 2 years of follow-up. At final follow-up, patients were asked to complete a subjective sports questionnaire, the Marx Activity Rating Scale, a visual analog scale (VAS), the Single Assessment Numeric Evaluation, and a satisfaction questionnaire. Changes in patient-reported outcome measures were assessed using nonparametric statistical testing.

RESULTS

A total of 21 patients met the inclusion criteria, of whom 17 were included for analysis at an average follow-up of 7.5 years (range, 2.2-13.3 years). The average age at the time of surgery was 23.3 years (range, 16.9-36.2 years), and 76.5% of patients were female patients. The average VAS score decreased from 5.7 preoperatively to 2.6 postoperatively (P = .02). Of the 15 patients who participated in sports within 3 years prior to their surgical procedure, 14 (82.4%) returned to 1 or more sports at an average of 16.9 months (range, 6-36 months); however, only 46.7% were able to return to their preinjury level of participation or higher. Furthermore, 88.2% of patients reported being satisfied with their sport-related outcomes. Direct rates of sport-specific return were as follows: weightlifting, 100%; skiing, 100%; running, 66.7%; and basketball, 50%.

CONCLUSIONS

In our study population, concomitant MAT and DFVO afforded a high rate of RTS at an average of 16.9 months postoperatively, as well as a significant decrease in VAS pain scores. These findings are essential to note when counseling patients receiving these procedures who wish to resume sports and physical activities so that they may expect an extensive recovery process before they can RTS.

LEVEL OF EVIDENCE

Level IV, case series.

The Rule of 57: Orthopaedic Trigonometry Made Easy

INTRODUCTION

The Rule of 57 is an easy method for planning osteotomies and calculating translations when correcting spine and limb deformities.

METHODS

The rule is based on the mathematical principle that a circle with a radius of 57 mm has a circumference of 360 mm where each 1° of the circle subtends an arc of 1 mm in length.

RESULTS

Thus a 1 mm opening or closing wedge osteotomy with a width of 57 mm would result in 1° of angular correction.

DISCUSSION

This basic geometric shape can be extrapolated in many ways to determine proper alignment for preoperative planning, performing osteotomies, understanding guided growth, and executing a variety of deformity corrections.

Three-Dimensional Quantitative Magnetic Resonance Imaging of Epiphyseal Cartilage Vascularity Using Vessel Image Features: New Insights into Juvenile Osteochondritis Dissecans

We introduce a quantitative measure of epiphyseal cartilage vascularity and examine vessel networks during human skeletal maturation. Understanding early morphological changes in the distal femoral condyle is expected to provide information on the pathogenesis of developmental diseases such as juvenile osteochondritis dissecans.

Methods

Twenty-two cadaveric knees from donors ranging from 1 month to 10 years of age were included in the study. Images of bone, cartilage, and vascularity were acquired simultaneously with a 3-dimensional gradient-recalled-echo magnetic resonance imaging (MRI) sequence. The secondary ossification center volume and total epiphysis cartilage volume ratio and articular-epiphyseal cartilage complex and epiphyseal cartilage widths were measured. Epiphyseal cartilage vascularity was visualized for 9 data sets with quantitative susceptibility mapping and vessel filtering, resulting in 3-dimensional data to inform vessel network segmentation and to calculate vascular density.

Results

Three distinct, non-anastomosing vascular networks (2 peripheral and 1 central) supply the distal femoral epiphyseal cartilage. The central network begins regression as early as 3 months and is absent by 4 years. From 1 month to 3 years, the ratio of central to peripheral vascular area density decreased from 1.0 to 0.5, and the ratio of central to peripheral vascular skeletal density decreased from 0.9 to 0.6. A narrow, peripheral vascular rim was present at 8 years but had disappeared by 10 years. The secondary ossification center progressively acquires the shape of the articular-epiphyseal cartilage complex by 8 years of age, and the central areas of the medial and lateral femoral condyles are the last to ossify.

Conclusions

Using cadaveric pediatric knees, we provide quantitative, 3-dimensional measures of epiphyseal cartilage vascular regression during skeletal development using vessel image features. Central areas with both early vascular regression and delayed ossification correspond to predilection sites of juvenile osteochondritis dissecans in this limited case series. Our findings highlight specific vascular vulnerabilities that may lead to improved understanding of the pathogenesis and better-informed clinical management decisions in developmental skeletal diseases.

Clinical Relevance

This paradigm shift in understanding of juvenile osteochondritis dissecans etiology and disease progression may critically impact future patient management. Our findings highlight specific vascular vulnerabilities during skeletal maturation in a group of active young patients seen primarily by orthopaedic surgeons and sports medicine professionals.

The Ideal Location of the Lateral Hinge in Medial Closing Wedge Osteotomy of the Distal Femur: Analysis of Soft Tissue Coverage and Bone Density

BACKGROUND

Although an appropriate hinge position to prevent unstable lateral hinge fractures is well established in medial opening wedge high tibial osteotomy, the position during medial closing wedge distal femoral osteotomy has not been elucidated.

PURPOSE/HYPOTHESIS

The purpose was to evaluate the ideal hinge position that would prevent an unstable lateral hinge fracture during biplanar medial closing wedge distal femoral osteotomy based on soft tissue coverage and bone density around the hinge area. The hypothesis was that the ideal hinge position could be clarified by analyzing soft tissue coverage and bone density around the lateral hinge area.

STUDY DESIGN

Controlled laboratory study.

METHODS

In 20 cadaveric knees (mean age, 70.3 ± 19.2 years), the femoral attachment of the gastrocnemius lateral head was quantitatively analyzed as a soft tissue stabilizer using digital photography and fluoroscopy. Then, medial closing wedge distal femoral osteotomy was performed, locating the lateral hinge either inside (group 1) or outside (group 2) the femoral attachment of the gastrocnemius lateral head, and the incidence of unstable lateral hinge fractures was compared between the 2 groups. Cortical bone density around the lateral hinge was measured using Hounsfield units on 30 computed tomography scans and reconstructed as a 3-dimensional mapping model. The transitional zone with low bone density was regarded as the safe hinge position with an increased capacity for bone deformation.

RESULTS

The upper and lower margins of the femoral attachment of the gastrocnemius lateral head were 9.1 ± 0.9 mm above and 8.0 ± 1.4 mm below the upper border of the lateral femoral condyle, respectively, and the femoral attachment of the gastrocnemius lateral head was widest in the anteroposterior dimension 0.4 ± 1.7 mm above the upper border of the lateral femoral condyle. The incidence of unstable lateral hinge fractures during osteotomy was significantly decreased in group 1 compared with group 2 (group 1: 0/10; group 2: 5/10; P = .01). An isolated transitional zone with low bone density was observed in all 30 knees and located 1.3 ± 0.8 mm above the upper border of the lateral femoral condyle. Bone density of the transitional zone with low bone density was significantly lower than surrounding femoral cortices (P < .001).

CONCLUSION

Only the upper border of the lateral femoral condyle can be recommended as an ideal hinge position to prevent unstable lateral hinge fractures during biplanar medial closing wedge distal femoral osteotomy based on soft tissue coverage and bone density.

CLINICAL RELEVANCE

When the hinge is positioned at the upper border of the lateral femoral condyle during biplanar medial closing wedge distal femoral osteotomy, the risk of unstable hinge fractures can be minimized.

Osteotomies in the Multiple Ligament Injured Knee: When Is It Necessary?

The multiple ligament-injured knee is a complex injury requiring a comprehensive and thorough evaluation prior to tailoring an appropriate treatment plan. Surgical repair and reconstruction of the involved ligaments are frequently discussed in the literature; however, osteotomy to correct limb malalignment may be just as important to obtaining a good outcome. Limb realignment must be carefully evaluated and treated. Isolated soft tissue procedures are prone to failure if significant malalignment, deformity, and thrust are ignored. In select cases, osteotomy can lead to restored mechanical stability, optimal joint load distribution, improved survival of simultaneous soft tissue procedures, and better patient outcomes.

Combined autologous chondrocyte implantation and meniscus reconstruction for large chondral defect in the lateral compartment due to discoid lateral meniscus tear: A case report

Discoid lateral meniscus tear leads to large chondral defect in the lateral compartment of the knee joint. There are few effective treatments for large chondral defect in both the tibial and femoral sides with severe degenerative lateral meniscus. We have developed a combined autologous chondrocyte implantation and meniscus reconstruction technique using hamstring tendon. This technique allows biological reconstruction and avoids knee arthroplasty.

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Discoid lateral meniscus tear leads to large chondral defect.

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A combination of autologous chondrocyte implantation and meniscus reconstruction technique using hamstring tendon is introduced.

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This novel method allows biological reconstruction.