Anterior Closing Wedge Osteotomy for Failed Anterior Cruciate Ligament Reconstruction: State of the Art.

The sagittal anatomy of the proximal tibia has a bearing on the forces exerted on the cruciate ligaments. A high posterior tibial slope is now a well-known risk factor causing failure of anterior cruciate ligament (ACL) reconstructions. The posterior slope can be calculated on short or full-length radiographs, MRI scans, or three-dimensional CT scans. Reducing the slope surgically by a sagittal tibial osteotomy is biomechanically protective for the ACL graft. An anterior closing wedge osteotomy may be contemplated when the lateral tibial slope is greater than 12°, in the setting of ACL reconstruction failure(s). Careful surgical planning to calculate the correction, taking into account knee hyperextension and patella height, is critical to avoid complications. It can be done above, at, or below the tibial tuberosity level. A transtuberosity correction can be done with or without a tibial tubercle osteotomy. This complex surgery can be conducted safely by meticulous execution to protect the posterior hinge and neurovascular structures and achieving stable fixation with staples. The limited literature available justifies the usage of anterior closing wedge osteotomy in appropriately selected patients.

Role of joint distraction in osteoarthritis of the knee: Basic science, principles and outcomes.

The burden of knee osteoarthritis (OA) is increasing worldwide. Advanced tibiofemoral joint OA in young patients is particularly a problem with inferior results seen with total knee arthroplasty in this patient population. Knee joint distraction (KJD) has been evaluated recently as a joint preserving procedure for young patients with advanced tibiofemoral osteoarthritis, to delay the need for a primary total knee arthroplasty (TKA). This will decrease the risk for revision TKA later in life. KJD temporarily unloads the knee joint and keeps the tibia and femur separated over a course of 6 weeks. Outcomes of KJD appear promising. Through this article, the authors hope to share from their collective experience as well as the available literature on the basic science, principles of surgery and outcomes of KJD.

Comparison between 2D radiographic weight-bearing joint space width and 3D MRI non-weight-bearing cartilage thickness measures in the knee using non-weight-bearing 2D and 3D CT as an intermediary.

BACKGROUND: In knee osteoarthritis, radiographic joint space width (JSW) is frequently used as a surrogate marker for cartilage thickness; however, longitudinal changes in radiographic JSW have shown poor correlations with those of magnetic resonance imaging (MRI) cartilage thickness. There are fundamental differences between the techniques: radiographic JSW represents two-dimensional (2D), weight-bearing, bone-to-bone distance, while on MRI three-dimensional (3D) non-weight-bearing cartilage thickness is measured. In this exploratory study, computed tomography (CT) was included as a third technique, as it can measure bone-to-bone under non-weight-bearing conditions. The objective was to use CT to compare the impact of weight-bearing versus non-weight-bearing, as well as bone-to-bone JSW versus actual cartilage thickness, in the knee. METHODS: Osteoarthritis patients (n = 20) who were treated with knee joint distraction were included. Weight-bearing radiographs, non-weight-bearing MRIs and CTs were acquired before and 2 years after treatment. The mean radiographic JSW and cartilage thickness of the most affected compartment were measured. From CT, the 3D median JSW was calculated and a 2D projectional image was rendered, positioned similarly and measured identically to the radiograph. Pearson correlations between the techniques were derived, both cross-sectionally and longitudinally. RESULTS: Fourteen patients could be analyzed. Cross-sectionally, all comparisons showed moderate to strong significant correlations (R = 0.43-0.81; all p < 0.05). Longitudinal changes over time were small; only the correlations between 2D CT and 3D CT (R = 0.65; p = 0.01) and 3D CT and MRI (R = 0.62; p = 0.02) were statistically significant. CONCLUSION: The poor correlation between changes in radiographic JSW and MRI cartilage thickness appears primarily to result from the difference in weight-bearing, and less so from measuring bone-to-bone distance versus cartilage thickness.

Soft-Tissue Management and Neurovascular Protection During Opening-Wedge High Tibial Osteotomy.

Medial opening-wedge high tibial osteotomy (OW-HTO) is an excellent surgical option for patients with varus knee osteoarthritis. Medial collateral ligament (MCL) release and posterior neurovascular structure protection during OW-HTO are steps that often induce stress and nervousness during surgery, especially for surgeons in the earlier stages of their learning curve. While is it well-known that the MCL should be released during OW-HTO, the standard retraction techniques pose challenges in visualization and instrument placement in the surgical field. We present our technique, which illustrates an alternative method to manage the MCL and safely protect the neurovascular structures using a second and more posterior surgical window during OW-HTO.

Changes in Cartilage Thickness and Denuded Bone Area after Knee Joint Distraction and High Tibial Osteotomy-Post-Hoc Analyses of Two Randomized Controlled Trials.

High tibial osteotomy (HTO) and knee joint distraction (KJD) are joint-preserving treatments that unload the more affected compartment (MAC) in knee osteoarthritis. This post-hoc study compares two-year cartilage-thickness changes after treatment with KJD vs. HTO, and identifies factors predicting cartilage restoration. Patients indicated for HTO were randomized to KJD (KJDHTO) or HTO treatment. Patients indicated for total knee arthroplasty received KJD (KJDTKA). Outcomes were the MRI mean MAC cartilage thickness and percentage of denuded bone area (dABp) change two years after treatment, using radiographic joint space width (JSW) as the reference. Cohen's d was used for between-group effect sizes. Post-treatment, KJDHTO patients (n = 18) did not show significant changes. HTO patients (n = 33) displayed a decrease in MAC cartilage thickness and an increase in dABp, but an increase in JSW. KJDTKA (n = 18) showed an increase in MAC cartilage thickness and JSW, and a decrease in dABp. Osteoarthritis severity was the strongest predictor of cartilage restoration. Kellgren-Lawrence grade ≥3 showed significant restoration (p < 0.01) after KJD; grade ≤2 did not. Effect sizes between severe KJD and HTO patients were large for MAC MRI cartilage thickness (d = 1.09; p = 0.005) and dABp (d = 1.13; p = 0.003), but not radiographic JSW (d = 0.28; p = 0.521). This suggests that in knee osteoarthritis patients with high disease severity, KJD may be more efficient in restoring cartilage thickness.

Knee Joint Distraction Compared with High Tibial Osteotomy and Total Knee Arthroplasty: Two-Year Clinical, Radiographic, and Biochemical Marker Outcomes of Two Randomized Controlled Trials.

OBJECTIVE: Both, knee joint distraction (KJD) and high tibial osteotomy (HTO) are joint-preserving surgeries that postpone total knee arthroplasty (TKA) in younger osteoarthritis (OA) patients. Here we evaluate the 2-year follow-up of KJD versus TKA and KJD versus HTO in 2 noninferiority studies. DESIGN: Knee OA patients indicated for TKA were randomized to KJD (n = 20; KJDTKA) or TKA (n = 40). Medial compartmental knee OA patients considered for HTO were randomized to KJD (n = 23; KJDHTO) or HTO (n = 46). Patient-reported outcome measures were assessed over 2 years of follow-up. The radiographic joint space width (JSW) was measured yearly. In the KJD groups, serum-PIIANP and urinary-CTXII levels were measured as collagen type-II synthesis and breakdown markers. It was hypothesized that there was no clinically important difference in the primary outcome, the total WOMAC, when comparing KJD with HTO and with TKA. RESULTS: Both trials were completed, with 114 patients (19 KJDTKA; 34 TKA; 20 KJDHTO; 41 HTO) available for 2-year analyses. At 2 years, the total WOMAC score (KJDTKA: +30.4 [95% CI 23.0-37.9] points; TKA: +42.4 [95% CI 38.1-46.8]; KJDHTO: +21.6 [95% CI 13.8-29.4]; HTO: +29.2 [95% CI 23.6-34.8]; all: P < 0.05) and radiographic minimum JSW (KJDTKA: +0.9 [95% CI 0.2-1.6] mm; KJDHTO: +0.9 [95% CI 0.5-1.4]; HTO: +0.6 [95% CI 0.3-0.9]; all: P < 0.05) were still increased for all groups. The net collagen type-II synthesis 2 years after KJD was increased (P < 0.05). Half of KJD patients experienced pin tract infections, successfully treated with oral antibiotics. CONCLUSIONS: Sustained improvement of clinical benefit and (hyaline) cartilage thickness increase after KJD is demonstrated. KJD was clinically noninferior to HTO and TKA in the primary outcome.

Role of high tibial osteotomy in medial compartment osteoarthritis of the knee: Indications, surgical technique and outcomes.

Knee osteoarthritis (OA) is the most common joint disorder worldwide. In particular, primary knee OA often presents with a varus malalignment. This increases the loads going through the medial compartment resulting in cartilage degeneration and symptomatic arthritis. High tibial osteotomy (HTO) is the workhorse surgical procedure for treating medial knee OA. When performed precisely in the hands of an experienced surgeon, HTO can delay or avoid knee arthroplasty. Of note, outcomes of knee arthroplasty are at best unpredictable in patients of younger age. Hence, there is a growing need for joint preservation procedures for younger patients presenting with knee OA, of which HTO is one. Through this article, the authors of whom all are joint preservation surgeons with a special interest in osteotomy hope to share from their experience as well as the available literature on the indications, perioperative planning, surgical technique, outcomes as well as pearls and pitfalls of HTO.

Knee Joint Distraction as Treatment for Osteoarthritis Results in Clinical and Structural Benefit: A Systematic Review and Meta-Analysis of the Limited Number of Studies and Patients Available.

OBJECTIVE: Knee joint distraction (KJD) is a joint-preserving osteoarthritis treatment that may postpone a total knee arthroplasty (TKA) in younger patients. This systematic review and meta-analysis evaluates short- and long-term clinical benefit and tissue structure changes after KJD. DESIGN: MEDLINE, EMBASE, and Web of Science were searched for eligible clinical studies evaluating at least one of the primary parameters: WOMAC, VAS-pain, KOOS, EQ5D, radiographic joint space width or MRI cartilage thickness after KJD. Random effects models were applied on all outcome parameters and outcomes were compared with control groups found in the included studies. RESULTS: Eleven articles reporting on 7 different KJD cohorts with in total 127 patients and 5 control groups with multiple follow-up moments were included, of which 2 were randomized controlled trials. Significant improvements in all primary parameters were found and benefit lasted up to at least 9 years. Overall, outcomes were comparable with control groups, including high tibial osteotomy, although TKA showed better clinical response. CONCLUSIONS: Current, still limited, evidence shows KJD causes clear benefit in clinical and structural parameters, both short- and long-term. Longer follow-up with more patients is necessary, to validate outcome and to potentially improve patient selection for this intensive treatment. Thus far, for younger knee osteoarthritis patients, KJD may be an option to consider.

What is the minimum response rate on patient-reported outcome measures needed to adequately evaluate total hip arthroplasties?

BACKGROUND: Unknown is which response rate on patient-reported outcome measures (PROMs) is needed to both obtain an accurate outcome and ensure generalizability in evaluating total hip arthroplasty (THA) procedures. Without an evidence based minimum response rate (MRR) on THA PROMs, it is possible that hospitals report invalid patient-reported outcomes (PROs) due to a too low response rate. Alternatively, hospitals may invest too much in achieving an unnecessary high response rate. The aim of this study is to gain an insight into the MRR on PROMs needed to adequately evaluate THA procedures from a clinical perspective. METHODS: Retrospective study on prospective collected data of primary, elective THA procedures was performed. MRR was investigated for each PROM (NRS pain at rest, NRS pain during activity, EQ-5D-3L, HOOS-PS, anchor function, OHS, anchor pain and NRS satisfaction) separately to calculate the primary outcome: MRR for the THA PROMs set. MRR on a PROM needed to have (condition 1.) similar PRO change score (3 month score minus preoperative score) including confidence interval, (condition 2.) maintaining the influence of each change score predictor and (condition 3.) equal distribution of each predictor, as those of a 100% PROM response rate group. Per PROM, a 100%-group was identified with all patients having the PRO change score. Randomly assessed groups of 90% till 10% response rate (in total 90 groups) were compared with the 100%-group. Linear mixed model analyses and linear regressions were executed. RESULTS: The MRR for the THA PROMs set was 100% (range: 70-100% per PROM). The first condition resulted in a MRR of 60%, the second condition in a MRR of 100% and the third condition in a MRR of 10%. CONCLUSIONS: A 100% response rate on PROMs is needed in order to adequately evaluate THA procedures from a clinical perspective. All stakeholders using THA PROs should be aware that 100% of the THA patients should respond on both preoperative and 3 month postoperative PROMs. For now, taking the first step in improving evaluation of THA for quality control by achieving at least two of the three conditions of MRR, advised is to require a response rate on PROMs of 60% as the lower limit.

Knee joint distraction in regular care for treatment of knee osteoarthritis: A comparison with clinical trial data.

OBJECTIVES: Knee joint distraction (KJD) has been evaluated as a joint-preserving treatment to postpone total knee arthroplasty in knee osteoarthritis patients in three clinical trials. Since 2014 the treatment is used in regular care in some hospitals, which might lead to a deviation from the original indication and decreased treatment outcome. In this study, baseline characteristics, complications and clinical benefit are compared between patients treated in regular care and in clinical trials. METHODS: In our hospital, 84 patients were treated in regular care for 6 weeks with KJD. Surgical details, complications, and range of motion were assessed from patient hospital charts. Patient-reported outcome measures were evaluated in regular care before and one year after treatment. Trial patients (n = 62) were treated and followed as described in literature. RESULTS: Patient characteristics were not significantly different between groups, except for distraction duration (regular care 45.3±4.3; clinical trials 48.1±8.1 days; p = 0.019). Pin tract infections were the most occurring complication (70% regular care; 66% clinical trials), but there was no significant difference in treatment complications between groups (p>0.1). The range of motion was recovered within a year after treatment for both groups. WOMAC questionnaires showed statistically and clinically significant improvement for both groups (both p<0.001 and >15 points in all subscales) and no significant differences between groups (all differences p>0.05). After one year, 70% of patients were responders (regular care 61%, trial 75%; p = 0.120). Neither regular care compared to clinical trial, nor any other characteristic could predict clinical response. CONCLUSIONS: KJD as joint-preserving treatment in clinical practice, to postpone arthroplasty for end-stage knee osteoarthritis patient below the age of 65, results in an outcome similar to that thus far demonstrated in clinical trials. Longer follow-up in regular care is needed to test whether also long-term results remain beneficial and comparable to trial data.

Cartilage Quality (dGEMRIC Index) Following Knee Joint Distraction or High Tibial Osteotomy.

OBJECTIVE: High tibial osteotomy (HTO) and knee joint distraction (KJD) are treatments to unload the osteoarthritic (OA) joint with proven success in postponing a total knee arthroplasty (TKA). While both treatments demonstrate joint repair, there is limited information about the quality of the regenerated tissue. Therefore, the change in quality of the repaired cartilaginous tissue after KJD and HTO was studied using delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC). DESIGN: Forty patients (20 KJD and 20 HTO), treated for medial tibiofemoral OA, were included in this study. Radiographic outcomes, clinical characteristics, and cartilage quality were evaluated at baseline, and at 1- and 2-year follow-up. RESULTS: Two years after KJD treatment, clear clinical improvement was observed. Moreover, a statistically significant increased medial (Δ 0.99 mm), minimal (Δ 1.04 mm), and mean (Δ 0.68 mm) radiographic joint space width (JSW) was demonstrated. Likewise, medial (Δ 1.03 mm), minimal (Δ 0.72 mm), and mean (Δ 0.46 mm) JSW were statistically significantly increased on radiographs after HTO. There was on average no statistically significant change in dGEMRIC indices over two years and no difference between treatments. Yet there seemed to be a clinically relevant, positive relation between increase in cartilage quality and patients' experienced clinical benefit. CONCLUSIONS: Treatment of knee OA by either HTO or KJD leads to clinical benefit, and an increase in cartilage thickness on weightbearing radiographs for over 2 years posttreatment. This cartilaginous tissue was on average not different from baseline, as determined by dGEMRIC, whereas changes in quality at the individual level correlated with clinical benefit.

Mechanical strength of a new plate compared to six previously tested opening wedge high tibial osteotomy implants.

BACKGROUND: This study aimed to assess the mechanical static and fatigue strength provided by the FlexitSystem plate in medial opening wedge high tibial osteotomies (MOWHTO), and to compare it to six previously tested implants: the TomoFix small stature, the TomoFix standard, the ContourLock, the iBalance, the second generation PEEKPower and the size 2 Activmotion. Thus, this will provide surgeons with data that will help in the choice of the most appropriate implant for MOWHTO. METHODS: Six fourth-generation tibial bone composites underwent a MOWHTO and each was fixed using six FlexitSystem plates, according to standard techniques. The same testing procedure that has already been previously defined, used and published, was used to investigate the static and dynamic strength of the prepared bone-implant constructs. The test consisted of static loading and cyclical loading for fatigue testing. RESULTS: During static testing, the group constituted by the FlexitSystem showed a fracture load higher than the physiological loading of slow walking (3.7 kN > 2.4 kN). Although this fracture load was relatively small compared to the average values for the other Implants from our previous studies, except for the TomoFix small stature and the Contour Lock. During fatigue testing, FlexitSystem group showed the smallest stiffness and higher lifespan than the TomoFix and the PEEKPower groups. CONCLUSIONS: The FlexitSystem plate showed sufficient strength for static loading, and average fatigue strength compared to the previously tested implants. Full body dynamic loading of the tibia after MOWHTO with the investigated implants should be avoided for at least 3 weeks. Implants with a wider T-shaped proximal end, positioned onto the antero-medial side of the tibia head, or inserted in the osteotomy opening in a closed-wedge construction, provided higher mechanical strength than implants with small a T-shaped proximal end, centred onto the medial side of the tibia head.

Prognostic Factors for Return to Sport After High Tibial Osteotomy: A Directed Acyclic Graph Approach.

BACKGROUND: High tibial osteotomy (HTO) is increasingly used in young and physically active patients with knee osteoarthritis. These patients have high expectations, including return to sport (RTS). By retaining native knee structures, a return to highly knee-demanding activities seems possible. However, evidence on patient-related outcomes, including RTS, is sparse. Also, time to RTS has never been described. Furthermore, prognostic factors for RTS after HTO have never been investigated. These data may further justify HTO as a surgical alternative to knee arthroplasty. PURPOSE: To investigate the extent and timing of RTS after HTO in the largest cohort investigated for RTS to date and to identify prognostic factors for successful RTS. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Consecutive patients with HTO, operated on between 2012 and 2015, received a questionnaire. First, pre- and postoperative sports participation questions were asked. Also, time to RTS, sports level and frequency, impact level, the presymptomatic and postoperative Tegner activity score (1-10; higher is more active), and the postoperative Lysholm score (0-100; higher is better) were collected. Finally, prognostic factors for RTS were analyzed using a logistic regression model. Covariates were selected based on univariate analysis and a directed acyclic graph. RESULTS: We included 340 eligible patients of whom 294 sufficiently completed the questionnaire. The mean follow-up was 3.7 years (± 1.0 years). Out of 256 patients participating in sports preoperatively, 210 patients (82%) returned to sport postoperatively, of whom 158 (75%) returned within 6 months. We observed a shift to participation in lower-impact activities, although 44% of reported sports activities at final follow-up were intermediate- or high-impact sports. The median Tegner score decreased from 5.0 (interquartile range [IQR], 4.0-6.0) presymptomatically to 4.0 (IQR, 3.0-4.0) at follow-up (P < .001). The mean Lysholm score at follow-up was 68 (SD, ± 22). No significant differences were found between patients with varus or valgus osteoarthritis. The strongest prognostic factor for RTS was continued sports participation in the year before surgery (odds ratio, 2.81; 95% CI, 1.37-5.76). CONCLUSION: More than 8 of 10 patients returned to sport after HTO. Continued preoperative sports participation was associated with a successful RTS. Future studies need to identify additional prognostic factors.

Response rate and costs for automated patient-reported outcomes collection alone compared to combined automated and manual collection.

BACKGROUND: The response rate on patient-reported outcome measurements (PROMs) necessary to adequately evaluate a treatment and improve patient care is unknown. Hospitals generally aim for the highest possible response rate without insight into the increase in costs involved. This study aimed to investigate which PROMs response rate is achievable in relation to the costs in an orthopaedic practice. METHODS: In an observational study, patients planned for orthopaedic surgery were asked to participate per surgical procedure (5769 surgical procedures at 5300 patients). Patient-reported outcomes (PROs) collection with a digital online automated PROMs collection system (minimal effort) was compared to a combined automated system and manual collection (maximal effort). Response rate was calculated preoperative and at two postoperative time points separately, and on all three time points together. Costs were calculated for the study period, per year and per surgical procedure. Calculations were executed for all surgical procedures and for three subgroups: knee arthroplasty, hip arthroplasty and anterior cruciate ligament reconstruction (ACLR). RESULTS: Using maximal effort the response rate increased for all surgical procedures compared to minimal effort; the preoperative response rate from 86% to 100% and the postoperative response rates from 55% to 83% (3 or 6 months) and 53% to 83% (12 months). Concerning the response at all three time points for all surgical procedures, minimal effort resulted in 44% response rate and increased to 76% with maximal effort. Lowest postoperative response rates were found in the ACLR group for both maximal and minimal effort. A costs difference of €5.55-€5.98 per surgical procedure between maximal and minimal effort was found. CONCLUSIONS: A two times higher PROMs response rate for patients responding at all three time points (44% versus 76%) is achievable with maximal effort compared to the use of an automated PROMs collection system only. Manual collection adds a cost of €5.5-€6 per surgical procedure to automated PROMs collection alone. It is debatable if these additional costs are justifiable from a value-based health care perspective as the response rate for adequate evaluation of a treatment is still unknown.

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.

Predictors of Return to Work After High Tibial Osteotomy: The Importance of Being a Breadwinner.

BACKGROUND: Limited evidence exists on patient-relevant outcomes after high tibial osteotomy (HTO), including return to work (RTW). Furthermore, prognostic factors for RTW have never been described. PURPOSE: To investigate the extent and timing of RTW in the largest HTO cohort investigated for RTW to date and to identify prognostic factors for RTW after HTO. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Consecutive patients who underwent HTO between 2012 and 2015 were included. Patients received a questionnaire at a mean follow-up of 3.6 years. Questions were asked pre- and postoperatively regarding work status, job title, working hours, preoperative sick leave, employment status, and whether patients were their family's breadwinner. The validated Work Rehabilitation Questionnaire (WORQ) was used to assess difficulty with knee-demanding activities. Prognostic factors for RTW were analyzed using a logistic regression model. Covariates were selected based on univariate analysis and a directed acyclic graph. RESULTS: We identified 402 consecutive patients who underwent HTO, of whom 349 were included. Preoperatively, 299 patients worked, of whom 284 (95%) achieved RTW and 255 (90%) returned within 6 months. Patients reported significant postoperative improvements in performing knee-demanding activities. Being the family's breadwinner was the strongest predictor of RTW (odds ratio [OR], 2.92; 95% confidence interval [CI], 1.27-6.69). In contrast, preoperative sick leave was associated with lower odds of RTW (OR, 0.20; 95% CI, 0.08-0.46). CONCLUSION: After HTO, 95% of patients were able to RTW, of whom 9 of 10 returned within 6 months. Breadwinners were more likely to RTW, and patients with preoperative sick leave were less likely to RTW within 6 months. These findings may be used to improve preoperative counseling and expectation management and thereby enhance work-related outcomes after HTO.

Correction of Femoral Valgus Deformity.

In the past two decades, the insights in the causes and development of valgus leg deformities as well as the options for treatment with corrective osteotomies have dramatically changed. New definitions for deformity analysis and planning for corrections have better defined the patients suitable for femoral valgus deformity corrections. Biomechanical research on new osteotomy methods and stability of plate fixation have provided scientific background for the development of improved surgical techniques that are more accurate, safer, and provide for quicker rehabilitation and bone healing. This article provides an overview of the basic principles behind the correction of femoral valgus deformity. Both the analysis and planning of femoral valgus deformity correction as well as the results of systematic clinical reviews are provided. The current recommended surgical technique of biplanar medial closing-wedge supracondylar osteotomy is explained, and the first clinical results are reported. Finally, the authors describe some of the future directions and needs for treatment optimization of patients with femoral valgus deformity.

Smoking and unstable hinge fractures cause delayed gap filling irrespective of early weight bearing after open wedge osteotomy.

PURPOSE: The purpose of this study was to examine the osteotomy gap filling rate with new bone after open wedge high tibial osteotomy (HTO) without bone graft and the effects of smoking, lateral hinge fracture, and early full weight bearing. METHODS: A prospective series (N = 70) of open wedge HTOs with the TomoFix plate (DePuy Synthes, Umkirch, Germany) was performed. Radiologic follow-up examinations took place postoperatively, after 6 and 12 weeks, and after 6, 12, and 18 months to measure osteotomy gap filling at each follow-up. Bone healing was compared in smokers versus nonsmokers who underwent open wedge HTOs with intact lateral hinges. Fractured lateral hinges were classified according to the Takeuchi classification and separately analyzed regarding bone healing. Patients were randomly assigned to undergo early (11 days) or standard (6 weeks) full-weight-bearing rehabilitation. RESULTS: A delay in the osteotomy gap filling rate between smokers and nonsmokers could be observed at all follow-up periods, but differences were not significant. A fracture of the lateral hinge was found in 39% of the patients. A type I fracture was observed in 14% of patients, a type II fracture was observed in 13%, and a type III fracture was found in 6%. The highest increase in the osteotomy gap filling rate was observed between 12 weeks and 6 months after surgery in patients with intact lateral hinges. For patients with unstable type II fractures, the highest increase in the gap filling rate was delayed until 6 to 12 months. Early full weight bearing had no effect on the gap filling rate in any of the patient groups evaluated. CONCLUSIONS: This study shows that osteotomy gap filling after open wedge HTO is delayed in smokers and in patients in whom opening of the gap resulted in unstable lateral hinge fractures. Early full weight bearing did not have a significant effect on the gap filling rate. LEVEL OF EVIDENCE: Level III, prognostic study.