Medial Closing Wedge Distal Femoral Osteotomy

Morphological analysis of the distal femur as a surgical reference in biplane distal femoral osteotomy

Distal femoral osteotomy (DFO) is performed alone or with high tibial osteotomy (HTO) for patients with osteoarthritis and distal femur deformities. DFO is technically demanding, particularly when creating an anterior flange. Herein, we examined the morphological characteristics of the distal femur based on the cortical shape as a surgical reference for biplanar DFO. Computed tomography images of 50 valgus and 50 varus knees of patients who underwent biplanar DFO or total knee arthroplasty were analyzed. Axial slices at the initial level of the transverse osteotomy in the DFO and slices 10 mm proximal and 10 mm distal to that level were selected. The medial and lateral cortical angles and heights (MCLA, LCLA, MCH, and LCH) were measured on axial slices. Statistical comparisons were performed between the medial and lateral cortices and valgus and varus knees. MCLA and MCH were significantly smaller and lower, respectively, than LCLA and LCH (P < 0.01). The MCLA and MCH of varus knees were significantly smaller and lower, respectively, than those of valgus knees (P < 0.01). Surgeons should carefully observe morphological differences in the distal femur cortex, distinguishing between medial and lateral knees and varus and valgus knees during the creation of the anterior flange in the DFO.

Change in quality of life and return to work and sports after isolated closing-wedge distal femoral osteotomy

PURPOSE

To analyze return to work and sports, and health-related quality of life (HRQoL) after closing-wedge distal femoral osteotomy (CWDFO) for valgus deformity and lateral compartmental osteoarthritis.

METHODS

Thirty-three patients underwent isolated CWDFO in our center between January 2018 and June 2020 were enrolled, of whom 32 and 23 patients were included in the return-to-work and return-to-sports analyses, respectively. Short Form-36 (SF-36), Tegner score, Knee injury and Osteoarthritis Outcome Score (KOOS) and visual analog scale (VAS) pain score were compared preoperatively and postoperatively. And postoperative complications were recorded.

RESULTS

Overall, 33 patients were contacted at a mean follow-up of 37.94 ± 6.68 months, with a median age of 35 years (range: 26-63 years) at the surgery time. The physical component summary of SF-36 (p < 0.001) increased significantly at 1 year postoperatively. All patients returned to work, including 96.86% who returned to the same level of work in 1.89 ± 0.98 months, and to sports, including 78.26% who returned to the same sport level in 6.50 ± 2.05 months. Rates of returning to work (p = 0.215) and sports (p = 0.165) did not differ with work/sports intensity. Tegner scores (p = 0.025) and VAS pain scores (p < 0.001) decreased, and KOOS (p < 0.001) increased at 1 year postoperatively. Revision/conversion surgery was not required. In all, 30.43% patients reported a subjective decrease in sports ability; 82.61% patients considered their sports ability acceptable.

CONCLUSION

Patients returned to work/sports after isolated CWDFO, and had increased HRQoL. Patients playing high-impact sports had lower rates of returning to the same sport level, and may require preoperative counseling.

LEVEL OF EVIDENCE

IV, Case series.

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.

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.

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.

Anatomical implications of the subvastus approach on major vascular injury during a distal femoral osteotomy: a computed tomographic venography study

PURPOSE

This study evaluated major vascular injury risk in distal femoral osteotomy (DFO) via the subvastus approach and examined the relationship between the posterior border of the vastus medialis (VM) and the superficial femoral artery (SFA) and vein (SFV).

METHODS

Eighty limbs from 80 patients were evaluated using lower extremity computed tomographic venography. The positional relationship between the VM, SFA, and SFV was evaluated by measuring the angle between each structure and the horizontal reference point (VMA: VM angle, FAA (femoral arterial angle), FVA (femoral venous angle) and the distance between VM and the SFA and SFV (VMAD: VM-arterial distance, VMVD: VM-venous distance) in each axial slice (0/10/20/30/40 mm) proximal to the level of the superior patellar margin. The proximity of the posterior border of the VM and the SFA/SFV as a vertical distance, measured between the slice of the superior border of the patella and the slice where the posterior border of the VM contacted the SFA was evaluated. Single and multiple regression analyses were performed using the vertical distance as the objective variable.

RESULTS

As the slice shifted proximally, the VMA significantly increased (24.9 ± 8.5, 36.3 ± 8.8, 47.4 ± 11.8, 59.9 ± 14, 70.3 ± 13.7 degrees, respectively, p < 0.001 between all slices) and moved posteromedially from a medial direction. FAA (94.2 ± 7, 86.9 ± 9.2, 78.4 ± 9.7, 71.4 ± 9.8, 66.6 ± 10.5 degree, respectively, p < 0.001 between all slices) and FVA (100.6 ± 4.9, 98.3 ± 5.9, 93.7 ± 7.5, 88 ± 9.2, 81.1 ± 10.5 degrees, respectively, p < 0.001 between all slices) decreased and moved from a posterolateral to a posteromedial direction, while VMAD (35.4 ± 7.8, 24.1 ± 7.3, 14.3 ± 6, 8.4 ± 7, 6.2 ± 6.3 mm, respectively, p < 0.001 between all slices) and VMVD significantly decreased (42.7 ± 7.3, 32 ± 7.4, 22.4 ± 6.8, 14.5 ± 10.6, 8.7 ± 7.1 mm, respectively, p < 0.001 between all slices). The average vertical distance was 36 ± 9.3 mm (range 18.6-61.5 mm). The body height and the patellar length significantly affected the vertical distance.

CONCLUSION

The posterior border of the VM shifted posteromedially from distal to proximal and contacted the SFA at an average of 36 mm from the suprapatellar border. Surgeons should be aware of the risk of major vascular injury during exposure and osteotomy.

LEVEL OF EVIDENCE

Case series, Level IV.

[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.

Comparison and Validation of Preoperative Planning Techniques for Distal Femoral Osteotomies and Proximal Tibial Osteotomies

Preoperative planning is important for accurate intraoperative execution in many surgical fields. Planning for distal femoral osteotomies (DFOs) and proximal tibial osteotomies (PTOs) consists of choosing the level of the osteotomy, measuring the angle of the osteotomy based on hip-knee-ankle alignment, and choosing a proper osteotomy wedge size. Medical imaging IT solutions company Sectra has implemented a new osteotomy tool in their radiographic system that is simpler than the accepted standard of modified center of rotation of angulation (mCORA) technique, yet unvalidated. In this study, we aim to compare the Sectra osteotomy tool versus the mCORA technique to measure the osteotomy angles as well as wedge sizes in both DFOs and PTOs to validate this new tool.We enrolled n = 30 consecutive patients with DFOs and n = 30 PTOs from the last year. The Pearson correlation coefficient (PCC) along with descriptive statistics was used to evaluate for similarity between the two techniques. We also compared interobserver and intraobserver reliability using intraclass correlation coefficients (ICC).The PCC for osteotomy angles in DFOs and PTOs were both 0.998 (p < 0.001 for both). For wedge sizes, the PCC in DFOs was 0.993 and 0.980 in PTOs (p < 0.001 for both). ICCs were high for both interobserver measurements in osteotomy angles and wedge sizes (range: 0.989-0.999) as well as intraobserver measurements (0.994-0.999).The Sectra osteotomy tool is a validated tool for preoperative measurements of DFOs and PTOs. It is reliable and simpler than the current practice of the mCORA technique. We suggest future studies to analyze this Sectra osteotomy tool in other settings as to incorporate it into widespread clinical use.

Changes in Distribution of Lower Limb Alignment After Total Hip Arthroplasty for Crowe IV Developmental Dysplasia of the Hip

Purpose

The purpose of this study was to evaluate the distribution of lower limb alignment in Crowe IV developmental dysplasia of the hip (DDH) before and after total hip arthroplasty (THA).

Patients and Methods

We retrospectively included 64 Crowe IV DDH patients (87 hips) who underwent THA between February 2010 and May 2019. Radiographic parameters were measured on full limb length standing anteroposterior radiographs, including hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), anatomical lateral distal femoral angle (aLDFA), and anatomical tibiofemoral angle (aTFA).

Results

HKA improved from 176.54°±3.52° preoperatively to 179.45°±4.31° at the last followup (P<0.001). According to the preoperative HKA, 40 hips were defined as knee valgus alignment. The majority of them were characteristic of a valgus mLDFA and a valgus or neutral mMPTA (35%, 47.5%). After THA, there were still 22 hips defined as knee valgus alignment. More than 50% of them were characteristic of a valgus mLDFA and a neutral mMPTA. Five hips (22.7%) revealed valgus alignment in both mLDFA and mMPTA. Twenty-one hips (24.1%) remained knee valgus alignment before and after surgery. One hip, defined as neutral alignment, preoperatively turned into valgus alignment after surgery.

Conclusion

Both preoperative and postoperative sources of valgus alignment were mainly from the femoral side among Crowe IV DDH patients. THA mainly played a positive role in the reconstruction of lower limb alignment in these patients.

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.