Physical activity after distal femur osteotomy for the treatment of lateral compartment knee osteoarthritis

Normo-or slightly overcorrection show better results after medial closing wedge high tibial osteotomy

PURPOSE

The objectives of this study were to evaluate functional results, revision-free survival, and the influence of postoperative alignment on outcomes after MCWHTO.

METHODS

This retrospective study included 27 MCWHTO operated on from 2009 to 2021. Radiographic measurements were performed pre- and postoperatively. The HKA (Hip-Knee-Ankle angle), MPTA (Medial Proximal Tibial angle), LDFA (Lateral Distal Femoral Angle), JLO (Joint Line Obliquity), and JLCA (Joint Line Convergence Angle) were evaluated. The Knee injury and Osteoarthritis Outcome Score (KOOS), the International Knee Society (IKS) Function and Knee Score, and the Subjective Knee Value (SKV) as well as revision-free survival were evaluated. Postoperative alignment and its influence on clinical outcomes were also analysed.

RESULTS

The mean follow-up was 61.9 months ± 31.4 (13-124). The HKA, MPTA, and JLCA angles were decreased post-operatively (respectively, Δ = 5.9° ± 2.6, p < 0.001; Δ = 6.1° ± 3.2, p < 0.001 and Δ = 2.5° ± 1.9, p < 0.001). LDFA and JLO were unchanged, post-operatively (respectively, Δ = 0.1° ± 2.2, p = 0.93 and Δ = 1.2° ± 3.3, p = 0.23). Postoperative HKA correlated with knee IKS (R = - 0.15, p = 0.04) and function IKS (R = - 0.44, p = 0.03). Postoperative LDFA correlated with knee IKS(R = 0.8, p < 0.01). Patients with postoperative HKA ≤ 180° had better KOOS (Δ = 12.3, p = 0.04) and IKS function (Δ = 28.1, p < 0.01) than those with HKA > 180°.

CONCLUSION

Functional results and revision-free survival after MCWHTO are satisfactory when the deformity is located in the proximal tibia. The joint line obliquity is not significantly altered with small tibial correction and, obtaining an overall neutral or slightly varus alignment under the conditions of this study allowed an improvement in the postoperative clinical scores. The literature is still inconclusive on the ideal alignment for valgus deformities and larger series are needed to draw definitive conclusions.

LEVEL OF EVIDENCE

IV, case series.

Short- to mid-term results of minimally invasive lateral unicompartmental knee replacement: 133 cases in a non-designer series

INTRODUCTION

The aim of the current study was to demonstrate short- to mid-term survivorship as well as clinical outcome of lateral unicompartmental knee replacement (UKR) with a fixed-bearing (FB) design from a non-designer center using the Oxford Fixed Lateral prosthesis.

MATERIALS AND METHODS

This single-center retrospective cohort study reports the results of 133 consecutive lateral FB-UKR. Survivorship analysis was performed with different endpoints and clinical outcome was measured using the Oxford-Knee-Score (OKS), American-Knee-Society-Score (AKSS-O), range-of-motion (ROM) and visual-analog-scale for pain (VAS).

RESULTS

There were two revision surgeries with conversion to total knee replacements (TKR) due to persistent pain resulting in a survival rate of 98.5% (95% CI 93.5-99.6) with a mean follow-up (FU) of 3.3 ± 1.8 years (range 1-8.5). All outcome scores, VAS and ROM showed a significant improvement at final FU (p < 0.001). The OKS improved from 26 ± 7.8 (range 11-45) preoperatively to 39 ± 8.3 (range 13-48), the AKSS-O from 49.2 ± 14.6 (range 18-90) to 81.8 ± 15.1 (range 40-100), the AKSS-F from 53 ± 23.7 (range 0-100) to 80.4 ± 21.4 (range 5-100) and the ROM from 118 ± 17 (range 90-160) to 134 ± 9.5 (range 100-155).

CONCLUSIONS

The short- to mid-term results following lateral FB-UKR demonstrate a high survivorship and good clinical outcome from an independent series. We, therefore, suggest that FB-UKR is a safe treatment option for isolated lateral OA if sufficient surgical experience is provided.

LEVEL OF EVIDENCE

Retrospective cohort study, level IV.

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.

A systematic review of outcomes of high tibial osteotomy for the valgus knee

PURPOSE

Osteoarthritis is a prolific condition in an increasingly ageing and obese population. Research into treatments of this condition and their efficacy are vital. Outcomes of high tibial osteotomy (HTO) for the varus knee is widely reported. There is less evidence for HTO in the valgus knee. This systematic review aimed to compile all literature reporting the outcomes of HTO to correct the valgus knee, focusing on post-operative clinical outcomes.

METHODS

Ovid MEDLINE, Embase and Web of Science were searched using key terms: Osteoarthritis [All Fields] AND High tibial osteotomy [All Fields] AND Lateral OR Valgus [All Fields]. Papers were screened for eligibility based on an inclusion and exclusion criteria. Full text screening was completed by two reviewers and data was extracted from the agreed included papers by one reviewer. Quality assessments of the papers were also conducted.

PROSPERO ID

CRD42021239045.

RESULTS

Across 17 papers reporting 517 knees, the average pre-operative femorotibial and hip-knee-ankle angles were corrected from 13.6 ± 7.0° and 4.9 ± 1.9° valgus to 2.8 ± 2.9° and 1.2 ± 1.7° varus. Studies show that the procedure is successful at offloading the lateral knee compartment and some evidence it can delay the need for a total knee replacement. However, its impact on overall quality of life remains poorly understood.

CONCLUSIONS

High tibial osteotomy may be a viable treatment option for valgus knee deformities caused by lateral compartment osteoarthritis. Nevertheless, research into the procedure remains limited. Importantly, our understanding of the relationship between the achieved alignment and outcome remains largely unknown.

LEVEL OF EVIDENCE

IV.

Distal femoral osteotomy versus lateral unicompartmental arthroplasty for isolated lateral tibiofemoral osteoarthritis with intra-articular and extra-articular deformity: a propensity score-matched analysis

Purpose

Lateral unicompartmental arthroplasty (UKA) and distal femoral osteotomy (DFO) represent surgical solutions in cases of valgus malalignment and isolated lateral osteoarthritis (OA) of the knee. The aim of the present study was to assess the clinical results, complications, and the overall postoperative alignment of a series of DFO and lateral UKA with a minimum 2-year follow-up in active middle-aged patients.

Methods

Patients with valgus knee and isolated lateral OA who underwent opening-wedge DFO or UKA from 2017 to 2019 were reviewed. Each patient was characterized by a joint line convergence angle (JLCA) > 3° and mechanical lateral distal femoral angle (mLDFA) < 87°. We excluded patients who underwent meniscus or osteochondral allograft during DFO. The Oxford Knee Score (OKS), Knee Injury and Osteoarthritis Outcome Score (KOOS), complications, and postoperative alignment were assessed. Propensity score matching was used to identify comparable patients.

Results

The DFO and lateral UKA groups consisted of 29 patients each. No statistically significant differences in gender, age, body mass index (BMI), length of follow-up, or limb deformity were reported between the two groups. In the DFO group, OKS was reported to improve from 27.51 to 38.59 (p < 0.05) and KOOS from 51.14 to 67.2 (p < 0.05). Similarly, in the UKA group, OKS improved from 26.23 to 35.43 (p < 0.05) and KOOS from 50.12 to 65.91 (p < 0.05). However, the improvement in OKS and KOOS (delta) did not differ between groups (p = 0.35 and p = 0.95). The DFO and UKA groups were characterized by similar postoperative hip-knee-ankle (HKA) angle measurements of −3.26 and −3.00, respectively (p = 0.65). No patients in the UKA group underwent revision or other knee surgeries during follow-up. No infections were detected in either group. In the DFO group, no cases of nonunion or delayed union were reported. However, 40% of DFO patients underwent plate removal. One patient in each group was characterized by progression of medial OA with Kellgren-Lawrence (KL) grade > 3.

Conclusion

UKA and DFO represent an effective treatment in lateral knee OA with intra-articular and extra-articular deformity. Both surgeries were able to provide a significant and comparable clinical improvement.

Level of evidence: III, comparative retrospective cohort study.

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.

Work intensity and quality of life can be restored following double-level osteotomy in varus knee osteoarthritis

PURPOSE

The purpose of this study was to assess changes in health-related quality of life (HRQL) and work intensity following double-level knee osteotomy (DLO). It was hypothesized that postoperative HRQL would be comparable to that of the general population and that work intensity can be restored in the short term.

METHODS

Twenty-four patients (28 varus knees; mechanical tibiofemoral angle: -11.0 ± 3.0° (-6.0 to -17.0), age: 49.1 ± 9.5 (31-65) years) who underwent DLO were included. The duration the patients were unable to work was evaluated. HRQL was measured with the SF-36 questionnaire, which consists of a physical (PCS) and mental component summary score (MCS). The pre- to postoperative changes in the PCS and MCS were analysed. The PCS and MCS were also compared to those of the general population, who has a reference score value of 50 points. The work intensity measured with the REFA classification and the Tegner activity scale were assessed preoperatively and at the final postoperative follow-up examination (18.0 ± 10.0 (5-43) months).

RESULTS

The duration that the patients were unable to work was 12.2 ± 4.4 (6-20) weeks. The PCS improved from 32.1 ± 11.3 (14.5-53.3) preoperatively to 54.6 ± 8.5 (25.2-63.7) (p < 0.001) at the final follow-up, and the MCS improved from 53.9 ± 11.1 (17.1-67.7) to 57.2 ± 3.1 (47.3-61.7) (n.s). The preoperative PCS was significantly lower than the reference score of the general population (p < 0.001), whereas the preoperative MCS was similar between the two groups (n.s.). At follow-up, no significant differences were observed between the PCS and the MCS of the patient group and those of the general population. Five patients who were unable to work prior to surgery due to knee symptoms returned to work with moderate (four patients) or even very heavy (one patient) workloads. The Tegner activity scale increased significantly from a median of 2.0 (0.0-5.0) to 4.0 (2.0-7.0) (p < 0.001).

CONCLUSION

Our results demonstrate an improvement in quality of life and return to working activity following DLO in the short term. The HRQL can be improved by DLO in patients with varus knee osteoarthritis to the level of the general population. These results can assist surgeons in discussing realistic expectations when considering patients for DLO.

LEVEL OF EVIDENCE

Study type: therapeutic, IV.

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.

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

CONTEXT

Distal femoral osteotomy (DFO) is a joint preservation procedure that corrects genu valgum deformities and patellofemoral maltracking, thereby restoring kinematics and unloading contact pressures in the lateral tibiofemoral and patellofemoral compartments.

OBJECTIVE

To evaluate the rates of return to work (RTW) and return to sport (RTS) after DFO for valgus malalignment and lateral compartment osteoarthritis through a systematic review of the literature.

DATA SOURCES

A systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted on the PubMed, Cochrane, and Embase databases.

STUDY SELECTION

The search terms femoral osteotomy AND (sports OR work) were used. Studies in which patients underwent concomitant total knee arthroplasty were excluded.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 4 (systematic review of level 4 studies).

DATA EXTRACTION

Data included the number of patients, age, gender, laterality of operation, time to follow-up, rate of RTW and RTS, time to RTS, activity level on return, and activity level scores (Tegner, Marx, Lysholm, and the International Knee Documentation Committee). Risk of bias was assessed using the Methodological Index for Non-Randomized Studies (MINORS) criteria.

RESULTS

Seven articles with 194 patients were included. The average age ranged from 19 to 49 years with a mean postoperative follow-up range of 36 to 90 months. RTW data were available for 125 patients, of whom 42.1% to 91.3% returned by final follow-up. Data on RTS were available for 149 patients, of whom 70% to 100% returned at a range of 8.3 to 16.9 months postoperatively, and 41.6% to 100% returned to the same or greater level of sports activity. The Tegner and Marx activity level scores ranged from 3 to 4 and from 5 to 11, respectively, at final follow-up.

CONCLUSION

Patients treated with DFO reported high rates of RTW and RTS, with most patients being able to return to recreational sport after surgery.

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.

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 Associated With Distal Femoral Osteotomy Survivorship: Data From the California Office of Statewide Health Planning and Development (OSHPD) Registry

Background:

Malalignment of the lower extremity can lead to early functional impairment and degenerative changes. Distal femoral osteotomy (DFO) can be performed with arthroscopic surgery to correct lower extremity malalignment while addressing intra-articular abnormalities or to help patients with knee osteoarthritis (OA) changes due to alignment deformities.

Purpose:

To examine survivorship after DFO and identify the predictors for failure.

Study Design:

Case series; Level of evidence, 4.

Methods:

Data from the California Office of Statewide Health Planning and Development, a statewide discharge database, were utilized to identify patients between the ages of 18 and 40 years who underwent DFO from 2000 to 2014. Patients with a history of lower extremity trauma, infectious arthritis, rheumatological disease, skeletal dysplasia, congenital deformities, malignancy, or concurrent arthroplasty were excluded. Failure was defined as conversion to total or unicompartmental knee arthroplasty, and the identified cohort was stratified based on whether they went on to fail. Age, sex, race, diagnoses, concurrent procedures, and comorbidities were recorded for each admission. Statistically significant differences between patients who required arthroplasty and those who did not were identified using the Student t test for continuous variables and a chi-square test for categorical variables. Kaplan-Meier survivorship curves were constructed to estimate 5- and 10-year survival rates. A Cox proportional hazards model was used to analyze the risk for conversion to arthroplasty.

Results:

A total of 420 procedures were included for analysis. Overall, 53 knees were converted to arthroplasty. The mean follow-up time was 4.8 years (range, 0.0-14.7 years). The 5-year survivorship was 90.2% (range, 85.7%-93.4%), and the 10-year survivorship was 73.2% (range, 64.7%-79.9%). The mean time to failure was 5.9 years (range, 0.4-13.9 years). Survivorship significantly decreased with increasing age (P = .004). Hypertension and a primary diagnosis of osteoarthrosis were significant risk factors for conversion to arthroplasty (odds ratio [OR], 3.12 [95% CI, 1.38-7.03]; P = .006, and OR, 2.42 [95% CI, 1.02-5.77]; P = .045, respectively), along with a primary diagnosis of traumatic arthropathy (OR, 10.19 [95% CI, 1.71-60.65]; P = .01) and a comorbid diagnosis of asthma (OR, 2.88 [95% CI, 1.23-6.78]; P = .02). Patients with Medicaid were less likely (OR, 0.11 [95% CI, 0.01-0.88]; P = .04) to undergo arthroplasty compared with patients with private insurance, while patients with workers’ compensation were 3.1 times more likely (OR, 3.08 [95% CI, 1.21-7.82]; P = .02).

Conclusion:

Older age was an independent risk factor for conversion to arthroplasty after DFO in patients ≥18 years but ≤60 years. Hypertension, asthma, and a diagnosis of osteoarthrosis or traumatic arthropathy at the time of surgery were predictors associated with failure, reinforcing the need for careful patient selection. The high survivorship rate of DFO in this analysis supports this procedure as a reasonable alternative to arthroplasty in younger patients with valgus deformities about the knee and symptomatic unicompartmental OA.

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.

Derotational osteotomy at the distal femur is effective to treat patients with patellar instability

PURPOSE

Increased femoral antetorsion influences patellofemoral joint kinematics. The aim of this study was to retrospectively evaluate the clinical outcome after derotational osteotomies and combined procedures in patients with patellofemoral instability.

METHODS

All patients with derotational osteotomies and combined procedures in patients with patellofemoral instability and increased femoral antetorsion performed between 2007 and 2016 were retrospectively analyzed. Exclusion criteria were open growth plates, posttraumatic deformities, and a follow-up period less than 12 months. Simple radiography and magnetic resonance imaging to evaluate cartilage lesions, trochlear dysplasia, tubercle distance, and osseous malalignment as frontal axis and torsion were performed on every patient. Patients were evaluated pre- and postoperatively using the visual analog scale (VAS) for pain, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, the subjective IKDC evaluation form, the Lysholm score, and the Tegner activity score.

RESULTS

Out of 222 femoral osteotomies, a total of 42 patients (44 knees) met the inclusion criteria. Mean preoperative femoral antetorsion of 31° (SD ± 9°) and mean valgus malalignment of 1° (SD ± 3°) were observed. An intended derotation of 12° (SD ± 5°) was set overall. The additional procedures included correction of valgus in 50% (n = 22), MPFL reconstruction in 64% (n = 28), patellofemoral arthroplasty in 18% (n = 8), trochleoplasty in 14% (n = 6), tibial tubercle transfer in 14% (n = 6). During the mean follow-up period of 44 months (SD ± 27, range 12-88), a total of five patients were lost to follow-up, resulting in a follow-up rate of 89% (n = 39). A significant pain relief from VAS 4 (SD ± 3) to VAS 2 (SD ± 2) (p = 0.006) as well as improved scores, WOMAC: from 80 (SD ± 14) to 88 (SD ± 16) (p = 0.007), Lysholm: from 46 (SD ± 21) to 71 (SD ± 24) (p < 0.001), IKDC: from 54 (SD ± 13) to 65 (SD ± 17) (p < 0.001), were observed postoperatively. During the follow-up period, no patellar re-dislocation was observed.

CONCLUSION

Combined derotational osteotomy is a suitable treatment for patellar instability due to torsional malformity, as it leads to a significant reduction of pain, and a significant increase of knee function with good-to- excellent results in the short-term follow-up.

LEVEL OF EVIDENCE

IV.

Successful Return to Sport Following Distal Femoral Varus Osteotomy

OBJECTIVE

Distal femoral varus osteotomy (DFVO) is an effective treatment for unloading valgus knee malalignment; however, there is limited evidence on the ability for patients to return to athletics following this procedure. The purpose of this study is to report the functional outcomes and rate of return to sport for athletes that underwent DFVO.

DESIGN

A consecutive series of athletes that had undergone DFVO were retrospectively reviewed. Radiographs were assessed to determine preoperative and postoperative alignment. Institutional registries were used to collect preoperative and postoperative Marx Activity Scale, International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form scores, and return to sport.

RESULTS

Thirteen patients (8 males, 5 females) with a mean age of 24 years (range 17-35 years) and a mean follow-up of 43 months (range 24-74 months) were included in the study. Six patients underwent medial closing wedge DFVO versus 7 patients who underwent lateral opening wedge DFVO. Nine of 13 had concomitant chondral, meniscal, or ligamentous procedures performed. The mean alignment correction was 8° (range 5°-13°). All patients were able to successfully return to sport at a mean of 11 months (range 9-13 months). Furthermore, all 13 patients demonstrated an improvement in both Marx Activity Scale (4-11; P < 0.01) and IKDC scores (53-89; P < 0.01) after surgery.

CONCLUSIONS

Correction of valgus knee malalignment through DFVO-either medial closing wedge or lateral opening wedge-can reliably result in improvement in function and return to sport. Concomitant chondral, meniscal, and ligamentous pathology should be addressed.

Eight respectively nine out of ten patients return to sport and work after distal femoral osteotomy

PURPOSE

Distal femoral osteotomy (DFO) is a well-accepted procedure for the treatment of femoral deformities and associated symptoms including osteoarthritis, especially in younger and physically active patients in whom knee arthroplasty is undesirable. Still, there is an apparent need for evidence on relevant patient outcomes, including return to sport (RTS) and work (RTW), to further justify the use of knee osteotomy instead of surgical alternatives. Therefore, the purpose of the present study was to investigate the extent and timing of patients' RTS and RTW after DFO.

METHODS

This monocentre, retrospective cohort study included consecutive DFO patients, operated between 2012 and 2015. Out of 126 eligible patients (18-70 years, 63% female), all patients responded, and 100 patients completed the questionnaire. Median follow-up was 3.4 years (range 1.5-5.2). The predominant indication for surgery was symptomatic unicompartmental osteoarthritis and valgus or varus leg alignment caused by a femoral deformity. The primary outcome measure was the percentage of RTS and RTW. Secondary outcome measures included time to RTS/RTW, sports level and frequency, the median pre-symptomatic and postoperative Tegner activity score (1-10, higher is more active) and the postoperative Lysholm score (0-100, higher is better).

RESULTS

Out of 84 patients participating in sports preoperatively, 65 patients (77%) returned to sport postoperatively. Forty-six patients (71%) returned to sports within 6 months. Postoperative participation in high-impact sports was possible though less frequent compared to preoperative participation. Out of 80 patients working preoperatively, 73 (91%) returned to work postoperatively, of whom 59 patients (77%) returned within 6 months. The median pre-symptomatic Tegner activity score [4.0 (range 0-10)] was significantly higher (p < 0.01) than the reported Tegner score at follow-up [3.0 (range 0-10)]. The mean Lysholm score at follow-up was 68 (± 22). No significant differences were found between the osteoarthritis- and non-osteoarthritis group.

CONCLUSION

Eight out of ten patients return to sport and nine out of ten patients return to work after DFO. These are clinically relevant findings, because they further justify DFO as a surgical alternative to KA in young, active knee OA patients who wish to return to high activity levels.

LEVEL OF EVIDENCE

Retrospective cohort study, Level III.

A Preliminary Comparison Suggests Poor Performance of Carbon Fiber Reinforced Versus Titanium Plates in Distal Femoral Osteotomy

BACKGROUND

Carbon fiber-reinforced (CFR) polymer implants have theoretical advantages over titanium plates.

QUESTIONS/PURPOSES

The aim of the present study was to assess our early outcomes with CFR plates in lateral opening-wedge distal femoral osteotomy to correct valgus lower limb malalignment. We asked the following: (1) Did the CFR polymer implant change time to union when compared with the titanium implant? (2) Did the incidence of displacement of medial cortical fractures differ between the implants? (3) Did the incidence of complications differ between the two techniques, and did other factors, such as bone graft material used, affect healing?

METHODS

A retrospective review of 16 limbs treated with an opening-wedge distal femoral osteotomy for genu valgum using either titanium (n = 10) or CFR plates (n = 6) was performed. Patient and clinical covariates as well as the primary outcome of time to union and secondary outcome of fracture displacement were collected and analyzed.

RESULTS

Those treated with CFR plates had longer times to union than did those in the titanium-treated group (median, 121.5 vs 81.5 days, respectively). The incidence of fracture displacement was higher in the CFR plate-treated group (CFR, n = 5/6; titanium, n = 1/10). Although the CFR plate-treated group had a 33% nonunion incidence while the titanium group had no nonunions, the study lacked the power to show significance. Bone graft material used did not affect outcome. Complication rates were higher in the CFR plate-treated patients.

CONCLUSION

The CFR plate was associated with a longer time to unite and higher fracture displacement rate than the titanium plate. As this is a retrospective case series, further research is required to confirm these results and clarify best practices in plating of distal femoral osteotomy for deformity correction.

Smoking and obesity influence the risk of nonunion in lateral opening wedge, closing wedge and torsional distal femoral osteotomies

PURPOSE

Lateral distal femoral osteotomies (DFO) have recently been performed more frequently. In addition to realignment for varus and valgus deformity, the indication was extended with the introduction of torsional osteotomies in patellofemoral instability. The purpose of this study was to assess the general and technical risk factors for nonunion in lateral opening, closing and torsional DFO.

METHODS

A total of 150 lateral DFO [98 opening wedge (LOWDFO) and 52 closing wedge (LCWDFO)] were analyzed in regard to potential risk factors for nonunion until plate removal. Nonunion was defined as failure of osseous consolidation according to clinical and radiological evaluation.

RESULTS

In LOWDFO, the nonunion rate was 2%, in LCWDFO the rate was higher with 9.6%. Nicotine abuse (p = 0.009) and a higher body mass index (p = 0.003) were significant risk factors. Patient's age and gender, the wedge height, hinge fractures, monoplanar versus biplanar osteotomy as well as additional torsional osteotomies were not significant in regard of nonunion.

CONCLUSIONS

Lateral DFO have a low rate of complications and nonunion. Smoking and obesity were significantly associated with the risk of nonunion. Hinge fractures, monoplanar technique or complete bone cuts of the opposite hinge in torsional osteotomies did not negatively influence the nonunion rate in DFO.

LEVEL OF EVIDENCE

Level IV.

High Rates of Return to Sports Activities and Work After Osteotomies Around the Knee: A Systematic Review and Meta-Analysis

BACKGROUND

Knee osteotomies are proven treatment options, especially in younger patients with unicompartmental knee osteoarthritis, for certain cases of chronic knee instability, or as concomitant treatment for meniscal repair or transplantation surgery. Presumably, these patients wish to stay active. Data on whether these patients return to sport (RTS) activities and return to work (RTW) are scarce.

OBJECTIVES

Our aim was to systematically review (1) the extent to which patients can RTS and RTW after knee osteotomy and (2) the time to RTS and RTW.

METHODS

We systematically searched the MEDLINE and Embase databases. Two authors screened and extracted data, including patient demographics, surgical technique, pre- and postoperative sports and work activities, and confounding factors. Two authors assessed methodological quality. Data on pre- and postoperative participation in sports and work were pooled.

RESULTS

We included 26 studies, involving 1321 patients (69% male). Mean age varied between 27 and 62 years, and mean follow-up was 4.8 years. The overall risk of bias was low in seven studies, moderate in ten studies, and high in nine studies. RTS was reported in 18 studies and mean RTS was 85%. Reported RTS in studies with a low risk of bias was 82%. No studies reported time to RTS. RTW was reported in 14 studies; mean RTW was 85%. Reported RTW in studies with a low risk of bias was 80%. Time to RTW varied from 10 to 22 weeks. Lastly, only 15 studies adjusted for confounders.

CONCLUSION

Eight out of ten patients returned to sport and work after knee osteotomy. No data were available on time to RTS. A trend toward performing lower-impact sports was observed. Time to RTW varied from 10 to 22 weeks, and almost all patients returned to the same or a higher workload.

Nonunion and delayed union in lateral open wedge distal femoral osteotomies-a legitimate concern?

INTRODUCTION

Due to a supposed high rate of nonunions in lateral open wedge distal femur osteotomy (LOWDFO), the medial closing wedge technique has been favoured for a long time. The aim of this study was to report the occurrence of delayed- and nonunions following LOWDFO. We hypothesized that the occurrence of nonunions needing revision surgery is comparable to medial closing osteotomies.

METHODS

Forty-one patients were treated with LOWDFO with a minimum follow-up of 12 months. Parameters such as age, gender, body mass index, valgus angle, the heights of the opening wedge, as well as the type of osteotomy (biplane vs single plane) were collected. Delayed union and nonunion were evaluated on radiographs along with clinical symptoms.

RESULTS

The study group consisted of 21 females and 20 males, with a median age of 37 years at the time of surgery. Removal of hardware was performed in 63% after 1.3 years (0.6-2.1 years). The median preoperative valgus angle was 6.1° valgus (range 2-15.5°). The heights of the opening wedge ranged from 2 to 12 mm (mean 5.3 mm). Hinge fracture of the medial cortex was seen in 39%. Three patients had a delayed union, and one patient had a nonunion requiring revision surgery.

CONCLUSION

LOWDFO is a safe alternative to MCWDFO. Although radiolucency of the osteotomy gap can be evident on radiographs even after 12 months, this does not reflect the clinical finding. The nonunion rate is proven to be low and comparable with the nonunion rates of MCWDFOs as well as open wedge HTOs.

Gait analysis before and after corrective osteotomy in patients with knee osteoarthritis and a valgus deformity

PURPOSE

In this prospective study, the changes in kinetics and kinematics of gait and clinical outcomes after a varus osteotomy (tibial, femoral or double osteotomy) in patients with osteoarthritis (OA) of the knee and a valgus leg alignment were analysed and compared to healthy subjects.

METHODS

Twelve patients and ten healthy controls were included. Both kinetics and kinematics of gait and clinical and radiographic outcomes were evaluated.

RESULTS

The knee adduction moment increased significantly postoperatively (p < 0.05) and almost similar to the control group. Patients showed less knee and hip flexion/extension motion and moment during gait pre- and postoperatively compared to the controls. A significant improvement was found in WOMAC [80.8 (SD 16.1), p = 0.000], KOS [74.9 (SD 14.7), p = 0.018], OKS [21.2 (SD 7.5), p = 0.000] and VAS-pain [32.9 (SD 20.9), p = 0.003] in all patients irrespective of the osteotomy technique used. The radiographic measurements showed a mean hip knee ankle (HKA) angle correction of 10.4° (95 % CI 6.4°-14.4°).

CONCLUSION

In patients with knee OA combined with a valgus leg alignment, the varus-producing osteotomy is a successful treatment. Postoperatively, the patients showed kinetics and kinematics of gait similar as that of a healthy control group. A significant increase in the knee adduction moment during stance phase was found, which was related to the degree of correction. The HKA angle towards zero degrees caused a medial shift in the dynamic knee loading. The medial shift will optimally restore cartilage loading forces and knee ligament balance and reduces progression of OA or the risk of OA. A significant improvement in all clinical outcomes was also found.

LEVEL OF EVIDENCE

III.

Distal Femoral Osteotomy for the Valgus Knee: Medial Closing Wedge Versus Lateral Opening Wedge: A Systematic Review

PURPOSE

(1) To determine the radiographic correction/healing rate, patient-reported outcomes, reoperation rate, and complication rate after distal femoral osteotomy (DFO) for the valgus knee with lateral compartment pathology. (2) To summarize the reported results of medial closing wedge and lateral opening wedge DFO.

METHODS

We conducted a systematic review of PubMed, MEDLINE, and CINAHL to identify studies reporting outcomes of DFOs for the valgus knee. Keywords included "distal femoral osteotomy," "chondral," "cartilage," "valgus," "joint restoration," "joint preservation," "arthritis," and "gonarthrosis." Two authors first reviewed the articles; our study exclusion criteria were then applied, and the articles were included on the basis relevance defined by the aforementioned criteria. The Methodological Index for Nonrandomized Studies scale judged the quality of the literature. Sixteen studies were relevant to the research questions out of 191 studies identified by the original search.

RESULTS

Sixteen studies were identified reporting on 372 osteotomies with mean follow-up of 45 to 180 months. All studies reported mean radiographic correction to a near neutral mechanical axis, with 3.2% nonunion and 3.8% delayed union rates. There was a 9% complication rate and a 34% reoperation rate, of which 15% were converted to arthroplasty. There were similar results reported for medial closing wedge and lateral opening wedge techniques, with a higher conversion to arthroplasty in the medial closing wedge that was confounded by longer mean follow-up in this group (mean follow-up 100 v 58 months).

CONCLUSIONS

DFOs for the valgus knee with lateral compartment disease provide improvements in patient-reported knee health-related quality of life at midterm follow-up but have high rates of reoperation. No evidence exists proving better results of either the lateral opening wedge or medial closing wedge techniques.

LEVEL OF EVIDENCE

Level IV, systematic review of Level IV studies.

Good functional results of distal femoral opening-wedge osteotomy of knees with lateral osteoarthritis

PURPOSE

To evaluate the time-dependent functional outcome of patients with lateral knee osteoarthritis with increased valgus treated with lateral opening-wedge osteotomy to shift the load from the lateral to the medial compartment of the knee.

METHODS

Twenty-four consecutive patients with lateral knee osteoarthritis were treated with distal femoral opening-wedge varus osteotomy stabilized with the Puddu plate and bone transplantation. The mean age of the patients was 48 years (CI 40.3-55.7, range 31-62). The patients were evaluated by the Knee Injury and Osteoarthritis Outcome Score (KOOS) preoperatively and at 3 and 6 months, 1, 2, 5 and 10 years post-operatively. The knee osteoarthritis was graded according to the Kellgren-Lawrence radiological scoring system. The mean follow-up time was 7.9 years (CI 6.8-9.0, range 4.0-10.2).

RESULTS

The mean angular correction measured on pre- and post-operative radiographs was 9.6° (CI 7.7°-11.5°, range 4°-20°). All osteotomies healed. KOOS increased significantly during the first year by 28-122 % beyond the preoperative values for all the five subscores. This improvement remained at 10-year follow-up for those with surviving osteotomy. Six knees were converted to total knee arthroplasty (TKA) mean 6.4 years (CI 3.3-9.6, range 4.0-11.8) post-operatively. The osteotomy survival rate at 5 years was 88 % and at 10 years 74 %. The preoperative osteoarthritic grade did not increase significantly during the follow-up period, but was significantly correlated (r = -0.49), P = 0.019 to the KOOS subscore symptoms at the 2-year follow-up.

CONCLUSION

Distal femoral opening-wedge osteotomy for lateral knee osteoarthritis resulted in good functional recovery after 1 year and favourable midterm results. It may be a good treatment option for middle-aged patients with valgus knees and lateral osteoarthritis in order to prevent or postpone TKA.

LEVEL OF EVIDENCE

IV.