Background: Knee osteoarthritis (OA) is a progressive whole-joint degenerative disease and a major global cause of pain, disability, and reduced quality of life. Multiple medical, biologic, and surgical treatment options exist, yet optimal sequencing, patient selection, and timing of surgery remain areas of clinical uncertainty. A comprehensive synthesis of current evidence is required to guide individualized treatment pathways. Objective: To systematically review the literature on medical, intra-articular injection-based, and surgical management of knee osteoarthritis, with particular emphasis on comparative effectiveness, surgical indications, and optimal timing of operative intervention. Methods: This systematic review followed PRISMA guidelines. Searches of PubMed/MEDLINE, Scopus, Web of Science, and Cochrane Library were conducted for studies published between January 2000 and December 2024. Eligible studies included randomized controlled trials, cohort studies, and high-quality systematic reviews evaluating conservative management, intra-articular therapies, osteotomies, unicompartmental knee arthroplasty (UKA), and total knee arthroplasty (TKA). Data were extracted on patient characteristics, interventions, clinical outcomes, functional scores, and complications. Risk of bias was assessed using the Cochrane RoB tool, Newcastle–Ottawa Scale, and AMSTAR-2. A narrative synthesis was performed due to clinical heterogeneity. Results: A total of 432 records were identified, with 17 studies meeting inclusion criteria. Non-pharmacological strategies and NSAIDs provided symptomatic relief in early disease, while corticosteroids and hyaluronic acid offered short-term benefit. Platelet-rich plasma demonstrated longer-lasting improvements in early to moderate OA compared with corticosteroids and HA. High tibial and distal femoral osteotomies were effective joint-preserving procedures for younger, active patients with unicompartmental OA and malalignment. UKA yielded faster recovery and more natural knee kinematics in appropriately selected patients with isolated disease. TKA provided the most predictable long-term pain relief and functional improvement in advanced or multicompartmental OA, with implant survivorship exceeding 90% at 10–15 years. Timing and patient selection emerged as the most important determinants of surgical outcomes. Conclusion: Effective management of knee OA requires a stage-specific, individualized approach integrating conservative, biologic, and surgical strategies. Non-operative therapies remain foundational in early OA, while biologic injections may bridge symptoms until surgical intervention is appropriate. Osteotomy and UKA offer valuable joint-preserving options in selected patients, whereas TKA remains the definitive treatment for advanced disease. Aligning treatment modality with disease stage, alignment, compartment involvement, and patient goals optimizes long-term outcomes and joint function.

Morquio syndrome, a lysosomal storage disease, is associated with an increased risk of spinal cord ischemia with positioning changes. 1 Though uncommon in non-spine surgeries, intraoperative neuromonitoring (IONM) can facilitate prompt detection of ischemia. 2,3 We utilized IONM in an 11-year-old undergoing bilateral distal femoral osteotomies and lumbar epidural placement. After induction and supine baseline signal acquisition, the patient was positioned laterally. Signals were lost, and hypotension ensued. Phenylephrine and fluids were administered, but hypotension resolved only after supine repositioning. Without IONM, spinal cord ischemia may have caused permanent injury. This case emphasizes the importance of pre-positioning IONM in patients with Morquio Syndrome.

Derotational femoral osteotomy using a retrograde intramedullary nail with medial patellofemoral ligament reconstruction as a treatment for recurrent patellofemoral instability.

Background:Because a valgus deformity is frequently associated with patellar instability, medial closed wedge distal femoral osteotomy (MCWDFO) has gained popularity. While the influence of MCWDFO on the leg axis in the coronal plane is widely understood, information is relatively scarce on possible concurrent effects on the posterior distal femur angle (PDFA) and femoral torsion (FT) caused by different hinge axes.Hypothesis:The authors hypothesized that a neutral hinge axis changes only the alignment in the frontal plane and that rotation of the hinge axis significantly changes sagittal and axial anatomic parameters.Study Design:Descriptive laboratory study.Methods:The study used a 3-dimensional surgical simulation to perform MCWDFO with a stepwise increase in varization by 1° (0°-15°). Surface models were created from computed tomography scans of 12 cases of femoral valgus deformity and 23 physiologically aligned lower limbs, resulting in 6370 simulations. Anatomic landmarks were determined for each simulation to measure the hip-knee-ankle angle, mechanical lateral distal femoral angle, PDFA, and FT. Axial and sagittal rotations of the hinge axis were tested for their effects on the PDFA and FT.Results:Axial rotation of the hinge axis significantly affected the PDFA, with changes of 1.9°± 0.1° (mean ± SD) per 10° of rotation at a hinge closure angle of 10° (P < .001). Anterosuperiorly inclined sagittal hinge rotation was highly negatively correlated to FT changes (–0.82; P < .001). For the neutral hinge axis, only minimal nonsignificant changes were observed in the PDFA (P = .85) and FT (P = .98).Conclusion:With this 3-dimensional simulation study, a definition for a hinge axis in the MCWDFO could be found in which only coronal changes occur. By rotating the hinge axis in the axial plane, the PDFA can be significantly influenced; conversely, the FT can be changed by rotation in the sagittal plane.Clinical Relevance:Understanding the effect of hinge axis orientation in MCWDFO is crucial for enhancing surgical accuracy, thereby improving patient outcomes in treatments involving knee deformities and avoiding unintended changes.

Location of the popliteal artery during medial and lateral distal femoral osteotomy: A retrospective study using contrast-enhanced computed tomography-based three-dimensional models.

High correction accuracy and low complication rate of double-level knee varization osteotomy using the free-hand technique: A single-centre retrospective analysis of 26 cases.

Development and clinical application of a positioning device for the distal femoral closing wedge osteotomy.

ABSTRACTPurposeTo determine the biomechanical effects of a lateral hinge screw on postoperative fracture after medial closing wedge distal femoral osteotomy (MCWDFO). It was hypothesized that adding a lateral hinge screw would significantly increase the failure strength of the hinge.MethodsTwelve Sawbone femurs were used for the study. A biplanar cut was made, a protective lateral hinge pin was placed, and a 5 mm‐closing wedge osteotomy was performed in each specimen. After osteotomy, the hinge pin was removed in six specimens, and in the remaining six specimens, the hinge pin was replaced with a lateral hinge screw. A varus load was then applied utilizing a load frame in a single load‐to‐failure test. Failure was defined as the point just before a substantial drop in the force versus displacement curve. Nonparametric Wilcoxon rank‐sum test was performed to compare maximum load and stiffness between the hinge screw and no hinge screw groups with p < 0.05 considered the threshold of statistical significance.ResultsThe maximum load to failure was significantly higher in the hinge screw group versus the control group, 440 ± 70 N versus 256 ± 107 N (mean ± standard deviation), respectively. Load to failure was 72% higher in the hinge screw group versus the no hinge screw group. No significant difference in stiffness was found between the groups.ConclusionUsing a Sawbone model, the current data showed that placement of a lateral hinge screw significantly increased resistance to varus stress following MCWDFO compared with a construct having no screw. Additionally, no significant difference in stiffness was observed between the group with the hinge screw and the group without the screw. Further investigation should assess the clinical benefit of a hinge screw in reducing surgical morbidity during the postoperative period for patients undergoing a distal femoral osteotomy.Level of EvidenceN/A.

Objectives: High tibial osteotomies (HTOs) and distal femoral osteotomies (DFOs) are used to address lower limb malalignment in the setting of unicompartmental arthritis and/or soft tissue injuries. There is a paucity of research in regards the influence of preoperative bone marrow edema (BME) on outcomes after these procedures. The purpose of this study was to assess the association between preoperative BME on return to sport and patient reported outcomes following high tibial osteotomy and distal femoral osteotomy. Methods: We conducted a retrospective review of 153 knees undergoing primary HTO and DFOs with preoperative MRI’s available at our institution, from 2011 to 2021. BME was evaluated using magnetic resonance imaging (MRI). Preoperative subchondral BME on the tibia and femur was analyzed for the existence, position, extent, and volume of the BME. Associations between preoperative BME and postoperative outcomes at a mean follow-up of 5.36 ± 2.79 were evaluated. Outcomes asses were return to sport (RTS), IKDC, Lysholm, VAS pain, VAS, Tegner score, VAS sports, KOOS Symptoms, KOOS Pain, KOOS ADL,KOOS Sports, and KOOS QoL. Results: The final cohort size was 153 knees undergoing high tibial osteotomy (HTO) or distal femoral osteotomy (DFO). Of these, 108 patients (70.6%) completed patient-reported outcomes (PROs). Among the 153 knees analyzed, 112 knees (73.2%) showed evidence of bone marrow edema in the femur, tibia, or both. The average bone marrow edema volume was 4.2 ± 10.1 cm³ in the femur, 1.6 ± 4.1 cm³ in the tibia, and 5.7 ± 11.2 cm³ combined in the femur and tibia. There was no significant correlation with bone marrow edema and multiple PRO’s or return to sport in the HTO cohort. Nor was there any significant correlation with combined bone marrow edema and PRO’s or return to sport for the HTO cohort. There was no significant correlation with bone marrow edema and multiple PRO’s or return to sport in the DFO cohort. However with increasing bone marrow edema volume in the tibia in the DFO cohort, we found worsened IKDC (β=-1.685, p=0.020), VAS pain (β=1.808, p=0.037), VAS satisfaction (β=-1.685, p=0.020), VAS sports (β=2.297, p=0.015), KOOS Pain (β=- 2.390, p=0.009), and KOOS ADL (β=-2.523, p=0.008) at final follow-up. Conclusions: The present study demonstrated that increasing bone marrow edema volume in the tibia correlated very strongly with decreased PROs in DFO patients. However, preoperative subchondral BME did not influence return to sport in HTO or DFO patients. There was no correlation between patient reported outcomes with the existence, position, extent, and volume of BME in HTO patients. Our findings suggest increasing preoperative bone marrow edema in the tibia may be associated with worse outcomes following DFO.

Objectives:High tibial osteotomies (HTO) and distal femoral osteotomies (DFO) may be used for a variety of knee pathologies including unicompartmental cartilage disorders and ligamentous instability. A novel instrumentation system for osteotomies utilizing three-dimensional patient-specific instrumentation (3D-PSI) cutting guides has been recently described, however there is limited reporting on the clinical outcomes and accuracy of this system. The purpose of this study was to evaluate the clinical outcomes and accuracy of correction of a 3D-PSI osteotomy system for HTO’s and DFO’s. It was hypothesized that patients would have significant improvements in patient-reported outcome (PRO) scores and that at least 90% of patients would have coronal alignment within 10% of the planned correction.Methods:A prospectively maintained database of patients who underwent opening wedge (oW) or closing wedge (cW) HTO or DFO utilizing a 3D-PSI system (Fine Osteotomy, Bodycad, Canada) from October 2020 to January 2022 was reviewed.Preoperatively and postoperatively, PROs were collected, including the International Knee Documentation Committee Subjective Knee Form (IKDC), San Francisco 12 physical component score and mental component scores (SF-12 PCS and MCS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) including the stiffness (WOMAC-stiff), pain (WOMAC-pain), physical function (WOMAC-PF) and total (WOMAC-total) scores, the Lysholm score, Tegner activity scale, and subjective satisfaction (1-10 scale, with 10 indicating maximum satisfaction). A paired t-test was used to evaluate for differences in PRO’s from pre- to postoperatively.To assess coronal and mechanical alignment, mechanical medial tibial width ratio (mMTWr), defined as the distance from the medial aspect of the tibia to the point on the tibia where the mechanical axis intersects the tibial plateau divided by the entire width of the tibial plateau, was measured on standing whole-leg radiographs (Figure 1). Radiographic measurements were performed by two blinded independent raters. Intra-class correlation coefficients (ICC) were calculated to determine inter-observer reliability for radiographic measurements between raters and reliability between the raters and the Bodycad software’s pre-operative measurements. To analyze correction accuracy, the differences between the planned final mMTWR based on the preoperative plan and actual measured mMTWr (Figure 2) as well as the percentage of patients within 10% of the planned mMTWR were calculated. This 10% threshold was based on prior studies and corresponds to approximately 2 degrees of tibiofemoral angle.Results:Complete data sets were obtained for 23 cases (16 oW-HTO, 4 oW-DFO, 2 cW-DFO, 1 combined cW-HTO + oW-DFO) at mean follow-up of 2.6 years. Demographics for the cohort are shown in Table 1. Using a Bonferroni-corrected P value (p<0.006), there were significant improvements from pre- to post-operatively in IKDC, Lysholm, WOMAC-pain, WOMAC-stiffness, WOMAC-physical function, and WOMAC-total scores (Table 2).The ICC’s for pre- and post-operative mMTWR measurements were 0.996 and 0.982, respectively, indicating near perfect agreement. The ICC between the raters pre-operative measurements of mMTWr on whole-leg standing radiographs and the Bodycad measurements of mMTWr based on the 3D CT was 0.985. 89% of patients were within 10% of the planned final mMTWR, and the median difference between the planned and actual correction was 3.7% (95% CI, 2.8 – 8.4).Excluding patients who underwent removal of hardware, 22% (5/23) of patients had at least one related reoperation. Survivorship, defined as patients who did not undergo revision osteotomy or arthroplasty, was 21/23 knees (91%).Conclusions:This study found that patients who underwent corrective HTO or DFO using PSI had significant improvements in PRO’s, and there was good accuracy, 89%, of coronal correction. These findings demonstrate that osteotomy utilizing 3D-PSI can lead to clinically meaningful improvements in patient function with high accuracy of planned correction. While the median difference of 3.7% between the planned and actual correction is less than 1 degree, the presence of outliers emphasizes the importance of meticulous surgical technique and abiding by osteotomy principles even when utilizing 3D PSI. This study adds to a growing body of literature that corrective osteotomies can significantly improve patients’ quality of life and knee function in the treatment of chondral and meniscal pathologies and provides early data on the accuracy and outcomes of a newly released 3D PSI osteotomy system for HTO’s and DFO’s.

Background: Several modifiable pathologic variables can contribute to lateral patellar instability, including trochlear dysplasia, increased tibial tubercle to trochlear groove (TT-TG) distance, femoral valgus alignment, and the integrity of the medial patellofemoral ligament (MPFL). Indications: For patients with a failed primary MPFL reconstruction or those with extreme pathoanatomy, adjunctive surgeries may be chosen in an a la carte approach to correct the pathoanatomy contributing to patellar instability. This case describes the treatment of a patient with severe trochlear dysplasia, femoral valgus alignment, increased TT-TG, and a torn MPFL treated with a 4-;pronged approach, including a trochleoplasty, distal femoral osteotomy (DFO), tibial tubercle osteotomy (TTO), and MPFL reconstruction. Technique Description: The patient is prepped and draped in a standard fashion. A medial incision is made over the distal femur. We begin with the DFO, utilizing a custom guide to remove a 6-;mm bone wedge before reduction and plating. Attention is then turned to the TTO. A freehand, 30° cut is made with an oscillating saw distally while an osteotome completes the osteotomy proximally. The tibial tubercle wedge is left without fixation while attention is turned to the trochleoplasty. A modified recession wedge technique is used to optimize the morphology of the trochlear groove. The trochleoplasty is secured with a central knotless polyether ether ketone (PEEK) anchor with sutures to 3 other anchors surrounding the lateral trochlea. The tubercle wedge is translated 10 mm anteromedially and 6 mm distally before fixation. Finally, the MPFL reconstruction is performed with 2 knotless PEEK patella anchors and a semitendinosus allograft. Care is taken to ensure the graft supplies appropriate patellar stabilization through flexion before final fixation. Results: Patients undergoing this 4-;pronged approach for severe lateral patellar instability are expected to return to activities of daily life. Rigorous physical therapy is needed immediately after surgery until at least 6 months postoperatively, with attention to restoring range of motion to prevent arthrofibrosis of the knee. Discussion/Conclusion: Patellar stabilization with concurrent trochleoplasty, DFO, TTO, and MPFL reconstruction can be used to treat patients with multiple pathoanatomic risk factors contributing to patellar instability. This level of surgery should only be implemented after careful selection of patients.

Objectives: Double-level osteotomy (DLO), comprising a medial open wedge high tibial osteotomy (MOWHTO) combined with a lateral closing wedge distal femoral osteotomy (LCWDFO), is an advanced surgical intervention for correcting severe varus malalignment and medial compartment osteoarthritis. While DLO has shown promising clinical outcomes, there is currently no comprehensive systematic review evaluating patient-reported outcomes (PROMs), conversion rates to total knee arthroplasty (TKA), complication rates, and alignment results. This systematic review aims to critically assess and synthesize the current literature on patient-reported outcomes, conversion rates to TKA, complication rates, and alignment results following DLO. The goal is to provide evidence-based guidance to physicians for optimizing treatment decisions and improving patient care in individuals with severe varus malalignment and/or symptomatic medial compartment osteoarthritis. Methods: Following the PRISMA guidelines, a systematic search was conducted in Scopus, PubMed, and Embase up to July 10th, 2024. The search terms included "double level osteotomy," "high tibial osteotomy," and "distal femoral osteotomy." Studies were included if they had over 5 participants and reported outcomes of DLO (MOWHTO + LCWDFO) with a mean follow-up greater than 1 year. Two independent researchers reviewed the articles, with disagreements resolved by consensus. Results: Patient-Reported Outcomes: Patient-reported outcomes (PROMs) following double-level osteotomy (DLO) demonstrated significant improvements across multiple studies. The Knee Injury and Osteoarthritis Outcome Score (KOOS), UCLA Activity score, and International Knee Documentation Committee (IKDC) subjective scores consistently increased postoperatively. Patient satisfaction was notably high, with a majority of patients reporting positive outcomes and significant improvements in quality of life. Complications: Complication rates varied across studies but were generally low. Minor complications included postoperative hematomas and scar dehiscences, while major complications were rare, ranging from deep wound infections to hinge fractures. Conversion to Total Knee Arthroplasty (TKA): Conversion rates to TKA were minimal with only one study reporting a clinical failure after DLO at follow-up periods of at least one year. The preservation of joint integrity post-DLO suggests that this procedure may delay or prevent the need for TKA in patients with severe varus deformity. Alignment: While studies reported varying alignment outcomes, most found that DLO effectively corrected all radiological parameters to normal ranges, successfully restoring limb alignment. Conclusions: Double-level osteotomy (DLO) results in significant improvements in patient-reported outcomes such as KOOS, IKDC, and Lysholm scores, with high patient satisfaction. The procedure effectively corrects radiological parameters to normal ranges, while complications are generally low and conversion rates to total knee arthroplasty (TKA) are minimal. This systematic review addresses a critical gap in the literature by providing a comprehensive evaluation of DLO outcomes. By synthesizing available evidence, it guides clinicians in optimizing patient care and offers valuable insights into the effectiveness and safety of this complex surgical approach.

Objectives:Medial patellofemoral ligament reconstruction (MPFLR) is a standard treatment for patellofemoral instability (PFI). Concomitant lateral retinacular release (LR) or lengthening (LL) is considered for patients with a tight lateral retinaculum. The purpose of this study was to investigate associations between demographic features, exam findings, and radiologically-measured patellofemoral parameters with LR/LL in patients undergoing primary MPFLR. We hypothesized that greater patellar tilt and lower ligamentous laxity would be associated with the use of LR/LL in conjunction with MPFLR.Methods:The Justifying Patellar Instability Treatment by Results (JUPITER) prospective, multicenter database was queried for patients who underwent primary MPFLR from January 2017 to July 2022. Patients with congenital or syndromic instability or habitual or fixed patellar dislocation or who had received a trochleoplasty or distal femoral osteotomy were excluded. Beighton scores of ≥4 were used to denote ‘pathologic’ ligamentous laxity. Binary logistic regressions were performed for multivariable analysis of factors associated with LR/LL and were reported as odds ratios (OR) and 95% confidence intervals (CI).Results:Of 428 patients (mean age: 16.7 ± 4.2 years, 64.5% female, 70.6% skeletally mature, 77.8% recurrent dislocators), 22.9% underwent LR (13.6%) or LL (9.3%). There were no differences in age, BMI, number of pre-operative instability events, or skeletal maturity between LR/LL and non-LR/LL patients. Those who underwent LR/LL were more frequently male (43.9% vs. 33.0%, P=0.049), had lower Beighton scores (2.6 ± 2.7 vs. 3.8 ± 2.9, P<0.001), and their surgeons were more likely to have completed a sports fellowship as opposed to a pediatric fellowship (82.7% vs. 64.8%, P<0.001) (Table 1). On pre-operative exam, LR/LL patients more often exhibited pathologic lateral patellar translation (62.2% vs. 49.1%, P=0.012). Intra-operatively, LR/LL patients more often dislocated in extension during examination under anesthesia (70.4% vs. 57.0%, P=0.017) and underwent a tibial tubercle osteotomy (TTO, 35.7% vs. 9.4%, P<0.001). 168 patients had available pre-operative imaging measurements, with LR/LL patients showing greater patellar tilt (24.1 ± 7.7° vs. 18.5 ± 16.7°, P<0.001). In multivariable analysis, sports fellowship training (2.99 [95% CI 1.58-5.65], P=0.001), and performing of a TTO (OR 5.23 [95% CI 2.77-9.88, P<0.001)]) were associated with LR/LL, while pathologic Beighton scores (OR 0.48 [95% CI 0.28-0.83], P=0.009) were associated with lower likelihood of LR/LL (Table 2).Conclusions:Approximately 23% of primary MPFLR patients from a large multicenter cohort underwent LR/LL. LR/LL was associated with less ligamentous laxity, increased patellar tilt, surgeon completion of a sports fellowship, and concomitant TTO. These data may help surgeons understand the relative factors associated with performing LR/LL in patients undergoing primary MPFLR.

Objectives:Patient-specific instrumentation (PSI) based on three-dimensional (3D) computed tomography imaging (CT) is increasingly being used for corrective high tibial osteotomies (HTO’s) and distal femoral osteotomies (DFO’s). These PSI cutting guides are based off of measurements on a 3D CT, however plain radiographs are typically used during the pre-operative evaluation to determine the need for an osteotomy, and it is unclear how well measurements on plain radiographs correlate to those performed on 3D CT.The purpose of this study was to evaluate the correlation between measurements of coronal alignment and posterior tibial slope (PTS) on plain radiographs and measurements by semi-automated PSI software on 3D CT. It was hypothesized that coronal and posterior tibial slope measurements on plain radiographs would significantly correlate with measurements on 3D CT by PSI software.Methods:Patients who underwent hip to ankle CT as part of the pre-operative workup prior to a opening wedge (oW) or closing wedge (cW) HTO or DFO from October 2020 to November 2023 were reviewed. Mechanical medial tibial width ratio (mMTWr, Figure 1) and medial PTS (Figure 2) were evaluated pre-operatively by two independent raters, orthopaedic sports medicine fellows, on standing whole-leg radiographs and a lateral radiograph of the knee, respectively. Lateral radiographs were excluded if they were malrotated, defined as greater than 5 mm distance between the posterior aspect of the medial and lateral femoral condyles. The mMTWr and PTS using the full length tibial anatomic axis were measured on 3D CT utilizing semi-automated commercial PSI software (Bodycad, Quebec, Canada) without any surgeon involvement (Figure 3).Intra-class correlation coefficients were calculated to determine the inter-rater reliability between raters and between the raters and the PSI software for each measurement. Pearson’s correlation coefficient and an independent t-test were respectively used to analyze for a correlation and difference between the raters’ and PSI software’s measurements. Significance was set at p<0.05.Results:Complete data sets were obtained for 91 cases (43 oW-HTO, 17 cW-HTO, 24 oW-DFO, 4 cW-DFO, 1 rotational HTO, 1 combined cW-HTO and oW-DFO, 1 combined cW-HTO and cW-DFO). 11 patients were excluded from PTS measurements due to malrotated lateral knee radiographs. Demographics for the cohort are shown in Table 1.The ICC between raters for pre-operative mMTWr measurements was 0.99. The ICC between the raters’ measurements of mMTWr on whole-leg standing radiographs and the PSI measurements of mMTWr based on the 3D CT was 0.99, and these two measurements were significantly correlated (r=0.99, p<0.001). There was no difference between the raters’ (40.8% ± 23.5) and the PSI measurement of mMTWr (41.3% ± 22.1, p>0.05).The ICC’s between raters for pre-operative PTS measurements was 0.82. The ICC between the raters’ measurements of PTS on standard lateral knee radiographs and PSI measurements of medial PTS based on the 3D CT was 0.63, and these two measurements were significantly correlated (r=0.72, p<0.001). There was a significant difference between the raters’ measurements (10.4° ± 3.4) and the PSI measurements of PTS (12.0° ± 3.2, p<0.001).Conclusions:This study found that coronal measurements performed on standard whole-leg radiographs and by semi-automated PSI software on 3D CT and standing whole-leg radiographs are highly correlated with near perfect agreement between modalities. PTS measurements had moderate correlation between plain radiographs and 3D CT, and PTS on lateral knee radiographs was, on average, 1.6° less than 3D CT, which utilizes the full-length tibia. Although the absolute value of slope is different between modalities, these data are important as they confirm that PTS on plain radiographs is a moderately reproducible measurement which correlates highly with 3D CT.Altogether, these data confirm that measurements on standing whole-leg and lateral knee radiographs are reproducible and accurate for evaluating coronal alignment and PTS pre-operatively.

BackgroundRecurrent patellar dislocation have become disabling condition and become a multifactorial disease with a spectrum different condition. Management of the disease remain difficult and controversial. Since it is related on functional anatomy and biomechanics of the patellofemoral joint, assessment of history and clinical evaluation of the patient are imperative to decide appropriate management plan. Surgical management is based on patients unique joint pathoanatomy and may be required different surgical approach either alone or in combination.Case presentationThis case details the clinical evaluation and surgical management of a female 37 year-old with history of persistent knee pain, recurrent patellar dislocation, and genu valgum. Patient exhibit significant anatomical abnormalities, including laterally dislocated patella, shallow trochlear groove with an anke 155°, sulcus angle between medial and lateral femoral facet is 145°, tibial tuberosity to trochlear groove (TT-TG) distance >20 mm, and patella alta by measuring Insall – Salvati ratio ( 1.4 )The surgical intervention involve lateral release and debridement arthroscopically, lateral open wedge distal femoral osteotomy, distalization and medialization of tibial tuberosity, and medial patellofemoral ligament (MPFL) reconstruction using gracilis tendon, resulting in successful realignment as confirmed by clinical evaluation and postoperative imaging. In this case, we can infer in addressing recurrent patellar dislocation with valgus deformity comprehensive surgical approach, we must consider complex anatomical variations, providing insight into effective management strategies.Rehabilitation protocol was applied with passive knee flexion, isometric quadricep contraction and ankle pump. Partial weight bearing was allowed after 4 weeks and gradually return to full weight bearing. Improvement of the patient was measured using Kujala score, average Lysholm score, VAS score and Tegner score showed significant improvementDiscussionWhen combination of treatments give patellar instability and function benefit with low rate recurrent instability. In mature skeletal, deformity can be assessed using Dejour criteria. It will lead to the variety of technically challenging surgical technique to reconstruct each found deformity. Medialization of TT combined with MPFL reconstruction can provide stability. Lateral opening wedge DFO medializes the tibial tubercle and decreased Q angle. In combination with lateral retinacular release help reduce subluxation vector on patella and decrease patellar instabilityConclusionThere is an important relationship between mechanical alignment and patellar instability. However there is no clear consensus on a consistent surgical algorithm. The outcome of this case suggests that combination of intervention associated with patellofemoral instability engender high satisfaction of the outcome

To evaluate: (i) return to sport (RTS) rates following distal femoral osteotomy (DFO) and lateral unicompartmental knee arthroplasty (UKA), including the likelihood of returning to pre-arthritic or higher levels of performance; (ii) participation in low-, intermediate- and high-impact sports pre- and postoperatively; and (iii) the ability of athletes to resume sporting activities at a professional or competitive level. A systematic literature search was conducted in PubMed, Embase and the Cochrane Library up to 17 June 2025. Studies were eligible if they focused on symptomatic lateral unicompartmental knee osteoarthritis as the primary indication and provided data on RTS outcomes. Outcomes of interest included RTS and return to performance (RTP) rates, sport participation categorized by impact level, return to play rates and sports-related patient-reported outcome measures. Random-effects models were utilized to evaluate RTS and RTP outcomes. Nine non-comparative studies (256 patients) were included. Five on DFO (127 patients; mean age 40.1 ± 13.3 years; mean follow-up 90.4 ± 72.3 months) and four on lateral UKA (125 patients; mean age 58.0 ± 8.8 years; mean follow-up 39.1 ± 16.2 months). Most studies provided Level IV Evidence and moderate quality (Methodological Index for Non-Randomized Studies score: 8-10). Random effect models provided RTS rates of 89.7% (95% confidence interval [CI]: 76.9-95.8) for DFO and 92.4% (95% CI: 81.5-97.1) for lateral UKA. RTP rates were 62.7% (95% CI: 41.1-80.2) and 88.5% (95% CI: 75.1-95.1), respectively. High-impact sport participation decreased after lateral UKA (11.5% to 3.4%), while remaining relatively stable following DFO (32.8% to 28.0%). Competitive-level athletes achieved a 100% RTS rate following DFO. Both DFO and lateral UKA are associated with high rates of RTS. However, lateral UKA often leads to a transition from high-impact to lower-impact activities. Clinicians can leverage these findings to optimize patient counselling and align postoperative RTS expectations with functional outcomes. Level IV, systematic review.

BackgroundUnicompartmental knee arthroplasty (UKA), high tibial osteotomy (HTO), and distal femoral osteotomy (DFO) are common knee-preserving surgeries for knee osteoarthritis (KOA), yet systematic comparisons of their effects on lower limb biomechanical parameters remain limited.ObjectiveTo retrospectively evaluate and compare the impacts of UKA, HTO, and DFO on hip-knee-ankle alignment in KOA patients, providing evidence for personalized surgical strategy formulation. We hypothesized that these procedures would exert differential effects on specific alignment parameters.MethodsA total of 256 patients with knee osteoarthritis were initially screened. After applying the inclusion and exclusion criteria, 150 patients were enrolled and assigned to the UKA, HTO, or DFO group (50 patients per group). Preoperative and postoperative changes in seven alignment parameters were measured: medial proximal tibial angle (MPTA), mechanical greater trochanter angle (MGTA), femorotibial anatomic angle (FTA), distal tibial femoral angle (DTTA), talar dome mechanical axis angle (TDMA), talar tilt angle (TTA), and the mechanical axis percentage (%MA). Intergroup differences in these parameters were analyzed statistically.Results(1) Baseline demographics and preoperative lower limb alignment parameters were comparable across groups. (2) UKA significantly changed MPTA, FTA, DTTA, TDMA, and %MA, but not MGTA or TTA. (3) DFO significantly changed MPTA, MGTA, FTA, and %MA, but not DTTA, TDMA, or TTA. (4) HTO significantly modified MPTA, MGTA, FTA, DTTA, TDMA and %MA, except for TTA. (5) UKA vs. HTO: No differences in FTA or DTTA, but significant differences in MPTA, MGTA, TDMA, TTA, and %MA. (6) UKA vs. DFO: No differences in MPTA or DTTA, but significant disparities in MGTA, FTA, TDMA, TTA and %MA.ConclusionUKA, HTO, and DFO each influence lower limb biomechanics in KOA patients, with distinct effects on specific alignment parameters. Surgical selection should prioritize individual anatomical and pathological characteristics to achieve personalized care.

ABSTRACTObjectiveHinge fracture is a known complication of lateral open wedge distal femoral osteotomy (LOWDFO). However, few studies have differentiated between intraoperative hinge fractures (IHF) and postoperative hinge fractures (PHF). This study aims to investigate the causes of these two types of fractures to help reduce complication rates and improve surgical outcomes.MethodsWe retrospectively analyzed data from 100 patients with genu valgum deformity and lateral unicompartmental osteoarthritis who underwent distal femoral osteotomy at our hospital between January 1st, 2022, and January 1st, 2024, in our hospital. Clinical parameters, radiological data, and the associated factors influencing IHF and PHF were analyzed. Radiological data such as mechanical axis deviation (MAD) and mechanical lateral distal femur angle (mLDFA) were collected. Clinical outcomes such as osteoarthritis index and time of healing were evaluated. Based on fracture morphology, IHF and PHF were further classified into Type 1 (extension), Type 2 (distal) and Type 3 (proximal) for detailed analysis. Statistical analyses included t‐tests, Chi‐square tests, and regression models to identify factors associated with IHF and PHF.ResultsA total of 87 patients were included in this study. The mean healing time of patients with all kinds of hinge fractures (3.4 ± 1.2 months) was longer than that of patients with no hinge fractures (2.8 ± 0.7 months), which was significant, p = 0.013. The MAD correction, mLDFA correction, and mLDFA correction ratio were related to hinge fractures (p = 0.010, 0.002, and 0.002 respectively). The body weight was higher in all types of hinge fractures group (IHF and PHF together) than the no hinge fractures group. The IHF group had a longer time of healing than the no IHF group. In the IHF group, the mLDFA correction (p = 0.005), mLDFA correction ratio (p = 0.005), and BMI (p = 0.031) were higher than the no IHF group. The PHF was related to hinge position. The group of hinge localized proximal to the adductor tubercle (AT) had a higher rate of PHF than the group of hinge localized in the adductor tubercle (p = 0.001). The healing time in the IHF group (3.9 ± 1.4 months) was significantly longer than the healing time in the PHF group (2.7 ± 0.4 months) (p = 0.002).ConclusionIn patients with genu valgum undergoing LOWDFO, IHF and PHF represent distinct clinical entities. IHF is associated with greater mLDFA correction, higher mLDFA correction ratios, and increased body weight. In contrast, PHF is primarily associated with hinge position, with a higher incidence observed when the hinge is located proximal to the adductor tubercle. Among the two, IHF has a more pronounced impact on delayed bone healing.Level of EvidenceRetrospective study Level IV.

Valgus deformity of the knee joint is caused by congenital anatomical abnormalities. The occurrence of an anterior cruciate ligament (ACL) tear in conjunction with a medial patellofemoral ligament (MPFL), alongside knee valgus deformity, is exceedingly rare in clinical practice. A 30-year-old female presented with congenital valgus knee. The left knee joint was immobile due to pain and swelling after trauma. The patient had a history of hypertension. The patient underwent an MRI of the left knee joint at a local hospital, and was diagnosed with ACL injury of the left knee, medial patellofemoral ligament (MPFL) injury of the patella, and congenital valva deformity. The patient underwent simultaneous reconstruction of the ACL and MPFL, as well as a distal femoral osteotomy. The patient experienced significant postoperative improvement, with marked pain relief. The knee remained stable, and functional recovery was observed. Failure to adequately address the stability of the patella following the rupture of the MPFL may result in increased stress on the ACL graft, thereby heightening the risk of graft failure. Additionally, valgus deformity can impose abnormal mechanical loads on the ACL graft, substantially elevating the likelihood of complications such as articular cartilage degeneration and meniscal injury. Usually, we need accurate guidance on imaging and evaluation of surgical options to successfully complete the surgery.

Treatment of adolescent genu valgum deformity using "wedgeless" distal femur osteotomy with K-wire fixation and cylindrical cast.