Surgical Technique and Preliminary Outcomes of Double-Level Osteotomy for Valgus Deformity.

Background: Data are limited regarding the surgical technique or outcomes of double-level osteotomy (DLO) combining medial closing-wedge distal femoral osteotomy and medial closing-wedge high tibial osteotomy in patients with moderate-to-severe valgus deformity. Purpose/Hypothesis: To describe the surgical technique and assess the short-term outcomes and surgical accuracy of DLO in patients with a moderate or severe valgus deformity. It was hypothesized that this technique would result in good clinical outcomes with precise deformity correction. Study Design: Case series; Level of evidence, 4. Methods: Eight patients (mean age, 44.2 ± 10.9 years) with a moderate or severe valgus knee treated with DLO (9 knees; mechanical tibiofemoral angle [mTFA], 10.3°± 3.5°) were included. The mean follow-up was 25.1 ± 11.1 months. Preoperative to postoperative changes in radiographic parameters (mTFA, mechanical lateral distal femoral angle, mechanical medial proximal tibial angle, joint line convergence angle) and clinical scores (Hospital for Special Surgery score, Oxford Knee Score, Lysholm score) were assessed. Surgical accuracy was calculated by subtracting the achieved postoperative correction from the preoperatively planned targeted correction. Results: The mTFA changed significantly from 10.3°± 3.5° preoperatively to -1.8°± 3.4° postoperatively (P < .001); the mechanical lateral distal femoral angle and mechanical medial proximal tibial angle changed significantly by 5.1°± 2.7° and 5.9°± 2.2°, respectively (P < .001 for both); and the posterior distal femoral angle decreased significantly from 85.9°± 3.1° to 84.2°± 2.4° (P < .01). There was no significant difference between pre- and postoperative joint line convergence angles (3.3°± 2.3° to 2.6°± 2.1°). The accuracy of the correction was high: the mTFA achieved postoperatively differed from the mTFA planned preoperatively by a mean of 2.7°± 1.9° (range, 0.6°-6.6°). Significant pre- to postoperative improvement was seen for all outcome scores (Hospital for Special Surgery, from 67 ± 11 to 93 ± 4; Oxford Knee Score, from 29 ± 7 to 43 ± 3; Lysholm, from 41 ± 24 to 89 ± 8; P < .001 for all). Conclusion: High surgical accuracy was achieved, and patients who underwent varus DLO for valgus knees showed improved knee function at short-term follow-up. Varus DLO can be a surgical option to restore the optimal alignment and joint line obliquity in patients with moderate or severe valgus malalignment.

Joint line and knee osteotomy.

This review explores the intricate relationship between knee osteotomy and frontal plane joint line orientation, emphasizing the dynamic nature of the joint line's influence on knee forces and kinematics. Consideration of coronal alignments, knee phenotypes, and associated angles (medial proximal tibial angle (MTPA), lateral distal femoral angle (LDFA), joint line convergence angle (JLCA)) becomes crucial in surgical planning to avoid joint line deformities. The double-level osteotomy is to be considered a valid option, especially for severe deformities; however, the target patient cannot be selected solely based on high predicted postoperative joint line obliquity (JLO) and MPTA.

Comparison of the indications for high tibial osteotomy and double-level osteotomy for the correction of diverse lower-leg deformities in an Asian population with medial compartment osteoarthritis: a retrospective observational study.

PURPOSE: Double-level osteotomy (DLO) for knee osteoarthritis is becoming increasingly popular to achieve superior anatomical correction. This study aimed to compare the indication for open-wedge high tibial osteotomy (OWHTO) and DLO and to investigate preoperative bone morphology. METHODS: Data of 166 knees treated with osteotomy were evaluated. The weight-bearing line ratio, mechanical lateral distal femoral angle (mLDFA), and mechanical medial proximal tibial angle (mMPTA) were measured. Bone deformity assessment and osteotomy simulation were conducted. Normal values of mLDFA and mMPTA were defined as 85-90°. Bone deformity was classified into four patterns: femoral, tibial, both, and no deformity. Simulation was performed to achieve a postoperative weight-bearing line ratio of 62%. Distal femoral osteotomy (DFO) or OWHTO was performed to achieve an mLDFA of 85° or mMPTA of up to 95°. If the postoperative parameter remained outside the correctable limit, DLO was performed. Cases were classified according to the corrective surgery performed, and those that could not be corrected after DLO were classified into the uncorrectable group. RESULTS: Femoral, tibial, both, and no deformities were observed in 14.2%, 37.8%, 10.7%, and 33.9% of cases, respectively. No cases were classified into the DFO group; however, 53.6%, 38.1%, and 8.3% were classified into the OWHTO, DLO, and uncorrectable groups, respectively. CONCLUSION: Bone deformity differed among cases, and only one-third had tibial deformity. OWHTO and DLO were indicated in approximately 50% and 40% of cases, respectively. Our study results reinforce the importance of evaluating leg morphology before surgical planning to achieve acceptable alignment.

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

PURPOSE: This study aims to identify the demographic and morphological features of valgus knee deformity with unilateral osteoarthritic knee in the coronal plane. A secondary aim was to identify the distinct phenotypes of valgus knees in Hirschmann's phenotype and the coronal plane alignment of the knee (CPAK) classifications before and after a knee osteotomy (KO). METHODS: A total of 107 patients (57 female and 50 male) with a mean age of 42.4 ± 17.2 years, who underwent varisation osteotomy for symptomatic unilateral knee osteoarthritis (OA) and constitutional valgus deformity, were enrolled in the study, and the mean follow-up period was 29.1 ± 7.3 months. The included cases comprised 60 cases of distal femoral osteotomy, 10 cases of double-level osteotomy and 33 cases of high tibial osteotomy. All patients underwent preoperative and postoperative clinical, functional and radiological evaluations, analysed by analysis of variance tests. RESULTS: An analysis of the location of the valgus deformities demonstrated that 56 cases (52.3%) were femoral based, 18 cases (16.8%) were both femoral and tibial based and 33 cases (30.9%) were tibial based. Twelve preosteotomy cases (11.2%) and 38 postosteotomy cases (35.5%) matched the most common eight Hirschmann's phenotypes, phenotyping the coronal lower limb alignment based on the native alignment in young patients without OA. Four (3.7%) preosteotomy cases and 89 postosteotomy cases (83.1%) matched the most common three CPAK phenotypes (Ⅰ, Ⅱ, Ⅴ) based on constitutional alignment and joint line obliquity in healthy and osteoarthritic knees. CONCLUSION: In valgus knee malalignment, the location of the deformity is not only solely femoral-based but also solely tibial-based or combined femoral and tibial-based. An individualised osteotomy approach would be recommended to achieve careful preoperative planning that considers the location of the deformity and the resultant joint line. Hirschmann's and CPAK classification would not be relevant when KO is considered. LEVEL OF EVIDENCE: Level Ⅳ, retrospective case-control study.

Development of a machine learning model for identifying the optimal situation favoring double-level osteotomy over single-level high tibial osteotomy.

BACKGROUND: This study aimed to develop a machine learning (ML) model to identify the optimal situation wherein double-level osteotomy (DLO) is favored for severe varus knees by analyzing unfavorable outcomes. This study hypothesized that there are the most favorable algorithms and contributing factors for identifying the optimal situation favoring DLO over opening-wedge high tibial osteotomy (OWHTO). METHODS: Data were retrospectively collected from patients who underwent OWHTO (505 knees). Unfavorable outcome parameters were defined as follows: (1) medial proximal tibial angle (MPTA) > 95°, (2) joint line convergence angle (JLCA) > 4° (insufficient medial release), (3) JLCA < 0° (medial instability), (4) recurrence of varus deformity, and (5) lateral hinge fracture. The input data for the ML model included demographic data and preoperative radiological and intra-operative factors. The ML model was used to evaluate overall and to evaluate each unfavorable outcome. Interpretation by the model was performed by SHapley Additive exPlanations. RESULTS: The unfavorable group had a larger JLCA and MPTA preoperatively than the favorable group in the conventional comparison. The light gradient boosting machine (LGBM) demonstrated the highest AUC of 0.66 and F-1 score of 0.72 among the ML algorithms. In the overall assessment, the preoperative weight-bearing line ratio (WBLR) was the factor that contributed the most, followed by the preoperative JLCA and the ΔWBLR. ΔWBLR and the preoperative JLCA were the contributing factors for each outcome. CONCLUSIONS: The LGBM model was superior in predicting the optimal situations favoring DLO over OWHTO. Preoperative WBLR, preoperative JLCA, and ΔWBLR significantly contributed to the unfavorable outcomes overall and for each outcome in the ML model.

Radiologic simulation of leg length change after double level osteotomy in preoperative surgical planning.

BACKGROUND: To evaluate the expected postoperative total leg length change using preoperative radiographs during surgical planning of four different methods of double level osteotomy (DLO). METHODS: This study included 34 patients (44 knees) who underwent DLO for varus knee osteoarthritis. Surgical planning was performed so that the postoperative weight bearing line ratio was 62.5%. In DLO, lateral closed or medial open wedge distal femoral osteotomy (LCWDFO, MOWDFO) was performed so that the postoperative mechanical lateral distal femoral angle was 85°, and residual deformity was corrected with medial open or lateral closed wedge high tibial osteotomy (MOWHTO, LCWHTO). Pre- and surgical planning X-rays in the one-leg standing position were compared to assess the change in leg length, and the factors affecting it, in the various surgical groups. The proportion of cases in which Δ total leg length was greater than 6 mm (symptomatic change) was investigated. RESULTS: The mean postoperative total leg length increased significantly with LCWDFO + MOWHTO, MOWDFO + MOWHTO, and MOWDFO + LCWHTO, while it decreased with LCWDFO + LCWHTO. The proportion of cases with a postoperative total leg length change > 6 mm was 72.7%, 2.3%, 100%, and 6.8% in LCWDFO + MOWHTO, LCWDFO + LCWHTO, MOWDFO + MOWHTO, and MOWDFO + LCWHTO, respectively. In addition, the preoperative hip-knee-ankle angle correlated negatively with the postoperative total leg length change in LCWDFO + MOWHTO, MOWDFO + MOWHTO, and MOWDFO + LCWHTO, but not in LCWDFO + LCWHTO. CONCLUSIONS: MOWDFO + MOWHTO had the largest postoperative leg length change and MOWDFO + LCWHTO had the smallest. Symptomatic leg length change (> 6 mm) should be considered in MOWDFO + MOWHTO and LCWDFO + MOWHTO.

A novel geometrical planning method to restore knee joint obliquity in double-level osteotomies.

PURPOSE: Precise preoperative planning is mandatory when a double-level osteotomy (DLO) is required to correct a severe knee deformity. Literature does not report a validated planning method regarding DLO that could be performed directly on digital radiographs using simple measurement tools. This study aims to validate a novel DLO planning method called New Mikulicz-Joint Line (NM-JL) based on essential measurement tools, in which the correction angles are induced by the predicted post-operative joint line obliquity (JLO). METHODS: Twenty-three patients who satisfied the inclusion criteria were enrolled. NM-JL planning method was performed using basic measurement tools to detect corrective angles and gaps. The correction was then simulated using a Virtual Segmentation Software method to obtain the osteotomy fragments. Both planning procedures were performed independently and later repeated by two orthopaedic surgeons to assess the inter and intra-observer reliability. RESULTS: The intraclass correlation coefficient (ICC) regarding corrective angles and gaps showed a significant positive correlation between the values determined using the two procedures by both raters (p < 0.05). Pearson's correlation analysis revealed a significant correlation between the measured results of the two planning methods. (p < 0.05). Finally, the Bland-Altman analysis showed an excellent agreement (p < 0.05) for all measurements performed. CONCLUSIONS: The NM-JL method showed high values of intra and inter-rater reliability. The procedure is built up starting from the predicted value of post-operative joint line obliquity, allowing to maintain this parameter fixed. Other advantages include the quickness, adaptability, and possibility to be performed on any Digital Imaging and Communication in Medicine (DICOM) viewer. LEVEL OF EVIDENCE: Level IV.

Assessment of return to sport and functional outcomes following distal femoral, double level and high tibial osteotomies for active patients with symptomatic varus malalignment.

PURPOSE: This study indicated the outcomes of three surgical techniques for the treatment of symptomatic unicompartmental knee osteoarthritis (UKOA) with varus malalignment in younger, active patients: distal femoral osteotomy (DFO), double-level osteotomy (DLO) and high tibial osteotomy (HTO). The outcomes measured included the return to sport, sport activity and functional scores. METHODS: A total of 103 patients (19 DFO, 43 DLO, 41 HTO) were enrolled in the study and were divided into three groups based on their oriented deformity, each undergoing one of the three surgical techniques. All patients underwent pre- and post-operative evaluations including X-rays, physical exams and functional assessments. RESULTS: All three surgical techniques were effective in treating UKOA with constitutional malalignment. The average time to return to sport was similar among the three groups (DFO: 6.4 ± 0.3 [5.8-7] months, DLO: 4.9 ± 0.2 [4.5-5.3] months, HTO: 5.6 ± 0.2 [5.2-6] months). The sport activity and functional scores improved significantly for all three groups, with no significant differences observed among the groups. CONCLUSION: Various knee osteotomy procedures, DFO, DLO, and HTO, result in high RTS rates and quick RTS times with satisfactory functional scores. Despite pre- to post-operative improvements in sport activities following DFO and DLO, pre-symptom levels were not reached following all evaluated procedures. LEVEL OF EVIDENCE: Retrospective case-control study, Level III.

Clinical and Radiological Outcomes of Double-Level Osteotomy Versus Open-Wedge High Tibial Osteotomy for Bifocal Varus Deformity.

Background: In bifocal varus deformity, double-level osteotomy (DLO) is advocated to treat lower limb alignment to prevent an adverse increase in joint line obliquity. Purpose/Hypothesis: The purpose of this study was to compare the clinical and radiological results after DLO and open-wedge high tibial osteotomy (OWHTO) in patients with combined varus deformity. It was hypothesized that DLO would improve clinical results without increasing the complication rate compared with OWHTO. Study Design: Cohort study; Level of evidence, 3. Methods: Inclusion criteria were medial tibiofemoral compartment pain, varus knee deformity with an abnormal medial proximal tibial angle <84° and a lateral distal femoral angle >90°, a functional anterior cruciate ligament, failure of nonoperative treatment, and a minimum 2-year follow-up with all clinical and radiological data. The rate of return to work or sports; the Knee injury and Osteoarthritis Outcome Score (KOOS); the University of California, Los Angeles (UCLA) activity score; and patient satisfaction were assessed at a minimum of 2 years of follow-up. Statistical comparison of the 2 groups was made using the chi-square or Student t test. Results: A total of 69 consecutive patients were analyzed, of whom 38 underwent OWHTO and 31 underwent DLO surgery. A significant between-group difference was found for all radiological parameters; in particular, there was less joint line obliquity after DLO compared with OWHTO (1.7° vs 5.6°; P < .001). DLO provided better outcomes compared with OWHTO regarding the UCLA score (4.3 vs 6.7; P < .001) and patient satisfaction (2.6 vs 3.9; P < .001), but no significant difference in KOOS or return to work or sports was observed. The OWHTO group had more hinge fractures than the DLO group (34.2% vs 12.9%; P < .001). Conclusion: For combined tibial and femoral varus deformity, DLO produced more physiologic joint line obliquity with slightly improved UCLA and patient satisfaction scores. A greater incidence of hinge fracture was observed after isolated OWHTO compared with DLO due to a larger tibial correction; however, this had little effect on clinical results at the 2-year follow-up.

Double-level knee osteotomy accurately corrects lower limb deformity and provides satisfactory functional outcomes in bifocal (femur and tibia) valgus malaligned knees.

PURPOSE: Double-level knee osteotomy (DLO) is a challenging procedure that requires precision in preoperative planning and intraoperative execution to achieve the desired correction. It is indicated in cases of severe varus or valgus deformities where a single-level osteotomy would yield significantly tilted joint line obliquity (JLO). This study aimed to evaluate the effectiveness of DLO in achieving accurate correction without compromising JLO, using patient-specific cutting guides (PSCGs), in cases of bifocal valgus maligned knees. METHODS: A single-centre, retrospective analysis of prospectively collected data for a total of 26 patients, who underwent DLO by PSCGs for valgus malaligned knees, between 2015 and 2020. Post-operative alignment was evaluated and the delta for different lower limb0.05, not statistically significant (ns)). All KOOS subs alignment parameters was calculated; the hip-knee-ankle angle (ΔHKA), medial proximal tibial angle (ΔMPTA), and lateral distal femoral angle (ΔLDFA). At the two-year follow-up, changes in the KOOS sub-scores, UCLA scores, lower limb discrepancy (LLD), and mean time to return to work and sport were recorded. All intraoperative and postoperative complications were recorded. The Mann-Whitney U test with a 95% confidence interval (95% CI) was used to evaluate the differences between two variables; one-way ANOVA between more than two variables and the paired Student's t-test was used to estimate the evolution of functional outcomes. RESULTS: The postoperative mean ΔHKA was 0.9 ± 0.9°, the mean ΔMPTA was 0.7 ± 0.7°, and the mean ΔLDFA was 0.7 ± 0.8° (all values with p > 0.05, not statistically significant (ns)). All KOOS subscore's mean values were improved to an extent two-fold superior to the reported minimal clinically important difference (MCID) (all with p < 0.0001). There was a significant increase in the UCLA score at the final follow-up (5.4 ± 1.5 preoperatively versus 7.7 ± 1.4, p < 0.01). The mean time to return to sport and work was 4.7 ± 1.1 and 4.3 ± 2.1 months, respectively. There was an improvement in Lower-limb discrepancy preoperative (LLD = 1.3 ± 2 cm) to postoperative measures (LLD = 0.3 ± 0.4 cm), ns. Complications were 2 femoral hinge fractures, 2 deep vein thromboses, 1 delayed tibial healing, and 1 hardware removal for hamstring irritation syndrome. CONCLUSION: DLO is effective and safe in achieving accurate correction in bifocal valgus malaligned knees with maintained lower limb length and low complication rate with no compromise of JLO. LEVEL OF EVIDENCE: III.

Preoperative Ahlbäck radiographic classification grade significantly influences clinical outcomes of double level osteotomy for osteoarthritic knees with severe varus deformity.

PURPOSE: The purpose of this study was to examine the relationship between preoperative Ahlbäck radiographic classification grade and the clinical outcomes of double level osteotomy (DLO) performed for osteoarthritic knees with severe varus deformity. METHODS: The study population comprised a consecutive series of 99 knees (68 patients) for which DLO was performed and follow-up results for a minimum of two years were available. The Ahlbäck radiographic classification system was used to determine the osteoarthritic grade. The following radiological parameters for alignment and bone geometry were measured: mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), joint-line convergence angle (JLCA), and mechanical tibiofemoral angle (mTFA). Clinical results were assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee (IKDC) subjective score preoperatively and at 2 years after surgery. Difference between preoperative and postoperative measurements as well as relationship between Ahlbäck grade and radiological/clinical results were statistically assessed. RESULTS: The average age of the study participants was 60.9 ± 6.2 years and the mean follow-up period was 45.4 ± 15.2 months. Each of the radiological parameters exhibited preoperative abnormal values. Knees with Ahlbäck grade 3 and 4 osteoarthritis exhibited significantly greater JLCA and mTFA than grade 1 knees. Two years post-surgery, all radiological parameter values measured within a normal range. Clinical evaluation showed significant improvement in KOOS after surgery. Analysis of the relationship between Ahlbäck grade and clinical score showed that the 2-year postoperative KOOS scores in grade 3 and 4 osteoarthritic knees were significantly lower than grade 1 knees (with the mean 2-year KOOS scores of 350.0 ± 79.9, 317.9 ± 78.3, and 420.2 ± 42.9, respectively). CONCLUSIONS: While DLO may produce significant radiological and clinical improvement in knees with joint space obliteration, Ahlbäck grade 3 and 4 osteoarthritic knees associated with larger JLCA and mTFA showed less satisfactory clinical results compared to grade 1 knees. LEVEL OF EVIDENCE: IV case series.

Double-level torsional osteotomy a treatment for the 'inwardly pointing knee' syndrome.

INTRODUCTION: A 'inwardly pointing knee' syndrome is a combined torsional deformity with increased femoral internal and tibial external torsion. After clinical and radiological verification of the torsional deformity and unsuccessful conservative therapy approach, a combined (double level) torsional osteotomy of femur and tibia might be the appropriate treatment. Here, we present the diagnostic algorithms, treatment, and outcome of combined torsional osteotomies of femur and tibia. The aim of the study is to show that patients treated with the procedure achieve patellofemoral stability and pain relief or reduction. MATERIAL AND METHODS: Twenty torsional osteotomies performed on 18 patients were included. Nine patients had experienced patellar dislocation in 11 joints before. All patients were suffering from anterior knee pain. All patients underwent a clinical and radiographical evaluation, including a torsion angle CT scan. Pre- and post-operatively multiple commonly approved scores (Lysholm Score, Tegner Activity score, Kujala Score, VAS and Japanese Knee Society score) were acquired. RESULTS: In 18 patients we performed 20 double-level torsional osteotomies. 9 patients suffered from patellar dislocations in 11 knee joints prior to surgery. All patients were suffering from anterior knee pain. Of these 7 patients achieved a stable joint after surgery without further patellar dislocations. All achieved more knee stability and experienced less patellar luxation then before surgery. The mean duration of follow-up was 59 months (range 9-173 months). The mean VAS was significantly reduced by 3.75 points (SD 2.09, p value 0.0002) from 5.50 points (SD 2.73, range 0-9) before surgery to 1.75 points (SD 1.67, range 0-5) after surgery. The Lysholm score increased significantly by mean of 27.6 (SD 17.55, p value 0.0001) from mean 62.45 (SD 22.71, range 22-100) before surgery to mean 90.05 (SD 10.18, range 66-100) after surgery. The Kujala Score did improve significantly in average by 25.20 points (SD 13.61, p value 0.00012) from mean 62.9 (SD 16.24, range 35-95) to mean 93.2 (SD 9.20, range 66-100). The Tegner activity score did increase significantly by 1.2 points (SD 1.47, p value 0.004) in average from mean 2.65 (SD 1.11, range 1-5) to mean 3.85 (SD 1.42, range 1-6). The Japanese knee score did increase significantly by 19.15 in average (SD 11.95, p value 0.0001) from mean 74.05 (SD 14.63, range 33-95) to mean 93.05 (SD 10.18, range 68-100). CONCLUSION: This is the first publication reporting about simultaneous double-level torsional osteotomies in a comparatively high number of patients. In addition, this is the first publication assessing the patient collective afterwards with objectifying clinical outcome scores. The results show that double-level torsional osteotomy is an effective treatment for patients with patellar dislocation or subluxation associated to torsional deformities of femur and tibia. Furthermore, we introduce a diagnostic algorithm for 'inwardly pointing knee' syndrome. LEVEL OF EVIDENCE: Level IV.

Can double-level osteotomy prevent patellofemoral osteoarthritis progression compared with open wedge high tibial osteotomy?

PURPOSE: To compare radiographic, clinical, and arthroscopic findings in patellofemoral (PF) osteoarthritis (OA) between open wedge high tibial osteotomy (OWHTO) and double-level osteotomy (DLO) with the same operative indication. METHODS: After adjustment for patient age, and coronal alignment, 36 knees with OWHTO alone and 36 knees with DLO were compared. Radiographic, clinical, and arthroscopic findings were documented before osteotomy. Arthroscopic findings were observed 1 year after osteotomy, and clinical and radiographic findings were observed 2 years after osteotomy. Patellar height was evaluated using the Insall-Salvati (IS) ratio, Carton-Deschamps (CD) index, and Blackburne-Peel (BP) index. Lateral patellar tilt and patellar shift were measured. A power analysis was performed. RESULTS: The postoperative CD and BP indices in the OWHTO group were lower than those in the DLO group (p < 0.001 and p = 0.001, respectively). The CD and BP indices in both groups significantly decreased postoperatively (all p < 0.001). Tilting angles in the OWHTO and DLO groups significantly decreased postoperatively (p < 0.001 and p = 0.002, respectively). There were no significant differences in American Knee Society scores, Kujala score, and the Knee Injury and Osteoarthritis Outcome Scores between both groups. The PF OA progression of the trochlear in the OWHTO group was higher than that in the DLO group (p = 0.002), and the PF OA progression of the patellar facet in the DLO group and anterior femoral condyle in both groups on the lateral side were higher than those on the medial side (p = 0.006, 0.032, and 0.041, respectively). CONCLUSIONS: DLO decreased the rate of low patellar height compared with OWHTO. DLO decreased the rate of PF OA progression in the trochlea compared with OWHTO. There were no significant differences in clinical outcomes in both groups. LEVEL OF EVIDENCE: Level III, case-control study.

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.

Double level osteotomy for genu varum: Is a return to sport possible?

INTRODUCTION: A double level osteotomy (DLO) may be indicated in patients with genu varum when the deformity involves both the tibia and femur. These patients, who are often young and active, have a high functional demand and hope for a rapid return to sport. The purpose of our study was to assess return to sport and functional outcomes following DLO for symptomatic genu varum. MATERIALS AND METHODS: A total of 40 patients (mean age 45.5±2 years) who underwent a DLO between 2018 and 2020, performed in 2 different hospitals, were reviewed after a minimum follow-up of 1-year. The mean initial varus was 11±2°. The type of sport and frequency of participation (UCLA activity score) as well as time to return to sport and level of activity recovered were defined as the primary endpoints. Functional scores were also assessed with the knee injury and osteoarthritis outcome score (KOOS). RESULTS: At the last follow-up, 87.5% (n=35) of patients reported that they had returned to sport. The mean time to return to sport was 6±1 months with a significant difference (p<0.001) between the pre- and postoperative UCLA activity scores. There was a strong correlation between the presence of a joint line obliquity >3° and decreased functional outcomes (p<0.0001). The overall KOOS score improved (p<0.001) by a mean of 38.6 points after the correction. The 8 lateral cortical fractures (Takeuchi type I and II) and the 2 medial cortical fractures (Nakayama type 1) that were found had no impact on functional outcomes (p>0.05). CONCLUSION: Our findings demonstrated that DLO provided rapid return to sport, thus making it possible to meet the functional demands and expectations of patients. LEVEL OF EVIDENCE: IV; Retrospective study.

Factors Associated With Unfavorable Radiological Outcomes After Opening-Wedge High Tibial Osteotomy for Varus Knees.

Background: Corrective osteotomy around the knee is based on deformity profiles of the femoral and tibial sides. Opening-wedge high tibial osteotomy (OWHTO) can be favored if the outcomes are not different, even if there is a certain degree of abnormal parameters after correction. Purpose/Hypothesis: The purpose of this study was to identify the factors associated with unfavorable radiological outcomes after OWHTO for varus knees. Our hypothesis was that there would be an optimal situation in which double-level osteotomy (DLO) has advantages over isolated OWHTO and an optimal cutoff value of structural parameters for which DLO should be considered in patients with severe varus knees. Study Design: Case-control study; Level of evidence, 3. Methods: The radiological and clinical outcomes of 337 patients who underwent OWHTO were retrospectively evaluated. A subgroup analysis was performed according to the weightbearing line ratio (WBLR) (group 1: <25th percentile; group 2: 25th-75th percentile; and group 3: >75th percentile) and factors associated with unfavorable radiological outcomes. For the assessment of cutoff values of the parameters favoring DLO, unfavorable radiological outcomes were categorized as follows: (1) medial proximal tibial angle (MPTA) >95°, (2) joint-line convergence angle (JLCA) >4° (insufficient medial release), (3) JLCA <0° (medial instability), (4) recurrence of a varus deformity, and (5) lateral hinge fracture. Results: The mean follow-up period was 66.2 ± 19.1 months. A low preoperative WBLR was related to a larger preoperative to postoperative change (Δ) in the WBLR, a larger reduction in coronal translation, a larger ΔMPTA, a wide preoperative lateral joint space, and a narrow preoperative medial joint space (P < .001, P < .001, P < .001, P = .016, and P = .003, respectively). However, only an MPTA >95° was significantly related to a low WBLR in the subgroup analysis according to unfavorable radiological outcomes (P = .038). The cutoff value of ΔWBLR causing an MPTA >95° was 46.5%, which showed a good area under the curve of 0.800, with a sensitivity of 74.4% and a specificity of 82.7%. The clinical outcomes significantly improved at the final follow-up compared with those preoperatively, with no significant differences between the WBLR groups. Conclusion: A ΔWBLR ≥46.5% led to an MPTA >95°. However, clinical outcomes were not affected. DLO should be considered if the surgeon desires a postoperative MPTA ≤95°.

Potential anatomic risk factors resulting oversized postoperative medial proximal tibial angle after double level osteotomy.

BACKGROUND: Double level osteotomy (DLO) has been introduced to prevent increased postoperative joint line obliquity. However, although DLO is planned, knees with postoperative medial proximal tibial angle (MPTA) > 95° in preoperative surgical planning are present. This retrospective study aimed to evaluate risk factors for an MPTA > 95° in preoperative surgical planning for DLO in patients with varus knee osteoarthritis (OA). METHODS: A total of 168 knees that underwent osteotomies around the knee for varus knee OA were enrolled. The hip-knee-ankle angle (HKA), weight-bearing line (WBL) ratio, mechanical lateral distal femoral angle (mLDFA), joint line convergence angle (JLCA) and mechanical medial proximal tibial angle (mMPTA) were measured on preoperative radiographs. The postoperative WBL ratio was planned to be 62.5%. When the postoperative mMPTA was more than 95° in isolated high tibial osteotomy (HTO), (DLO) was planned so that the postoperative mLDFA was 85°, and residual deformity was corrected by HTO. Knees with postoperative mMPTA ≤ 95° and > 95° were classified into the correctable group and uncorrectable group, respectively. RESULTS: DLO was required in 101 knees (60.1%). Among them, 41 knees (40.6%) were classified into the uncorrectable group. Binomial logistic regression analysis showed that preoperative JLCA and mMPTA were independent predictors in the uncorrectable group. CONCLUSIONS: Even with DLO, postoperative mMPTA was more than 95° in approximately 40% of cases. Preoperative increased JLCA and decreased mMPTA were risk factors for a postoperative mMPTA of > 95° after DLO.

Conceptos actuales en osteotomías en doble nivel alrededor de la rodilla / Current concepts in double-level osteotomies around the knee

Con la osteotomía en un solo nivel, se puede lograr la corrección del eje de la extremidad en pacientes con deformidades combinadas femoral y tibial, pero de forma simultánea generará una alteración patológica de oblicuidad de la interlínea articular, lo que conducirá a elongación ligamentaria, inestabilidad, degeneración condral y, en última instancia, comprometerá su sobrevida y los resultados funcionales. En virtud del análisis de la literatura más reciente, podemos concluir que existe un número significativo de pacientes que requieren de un procedimiento combinado para lograr un objetivo biomecánico óptimo. La finalidad de una osteotomía en doble nivel alrededor de la rodilla consiste en restablecer la anatomía normal, descargar el compartimiento afectado, normalizar los ángulos mecánicos y la orientación de la interlínea articular. Los ejes fisiológicos pueden restablecerse a través de un análisis preoperatorio exhaustivo, respetando principios biomecánicos y fijación estable con placas bloqueadas. Es un procedimiento demandante y con indicaciones en evolución, que progresivamente se ha instaurado como una alternativa de tratamiento justificada en estudios clínicos y biomecánicos para el manejo de deformidades severas alrededor de la rodilla.

With single-level osteotomy, correction of the limb axis in patients with combined femoral and tibial deformities can be achieved. This correction, however, will generate a pathological alteration in the joint line oblicuity, leading to ligament elongation, instability, joint degeneration and, ultimately, it will compromise the longevity and functional results of the correction. By analyzing the most recent literature, we can conclude that there is a significant number of patients who require a combined procedure to achieve an optimal biomechanical goal. The purpose of a double-level osteotomy around the knee is to restore normal anatomy, unload the affected compartment, normalize the mechanical angles and the orientation of the joint line. Physiological axes can be reestablished by means of a thorough preoperative analysis, observing the biomechanical principles and stable fixation with locked plates. It is a demanding procedure with increasing indications, which has progressively been established in clinical and biomechanical studies as a justified treatment alternative for the management of severe deformities around the knee.

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

INTRODUCTION: To compare bone union after medial closing wedge distal femoral osteotomy (MCWDFO) with that after lateral closing wedge distal femoral osteotomy (LCWDFO) using a novel scoring system. MATERIALS AND METHODS: The data of 30 patients who received biplanar MCWDFO for valgus knees (MCWDFO group) were retrospectively examined and compared to that of 22 patients (25 knees) who underwent biplanar LCWDFO via a double-level osteotomy (DLO) for varus knees (LCWDFO group). The progression of bone union of the transverse osteotomy plane in the femur was assessed using a newly developed scoring system using radiographs taken immediately after surgery and 3 and 6 months postoperatively. The scoring system is based on a scale of zero to six points with higher scores indicating better bone union. The incidence of hinge fractures was assessed using CT images, and the rates of reoperation were evaluated using medical record data. RESULTS: The mean bone union score was significantly lower in the MCWDFO group than in the LCWDFO group 3 months (2.1 ± 1.9 vs. 3.7 ± 1.7, P < 0.01) and 6 months (3.8 ± 2.1 vs 4.9 ± 1.5, P < 0.05) postoperatively. The incidence ratio of hinge fractures was significantly higher in the MCWDFO group than in the LCWDFO group (70.0% vs. 32.0%, P < 0.01). Two patients in the MCWDFO group underwent reoperation for delayed bone union or non-union. CONCLUSION: Bone union progression was slower and hinge fractures were more frequently observed after MCWDFO than after LCWDFO via DLO. MCWDFO is technically challenging, and patients must be monitored closely during and after surgery.

Surgical planning of osteotomies around the knee differs between preoperative standing and supine radiographs in nearly half of cases.

BACKGROUND: To evaluate the difference in surgical planning of osteotomies around the knee between preoperative standing and supine radiographs and to identify risk factors for discrepancies in surgical planning. METHODS: This study included 117 knees of 100 patients who underwent osteotomies around the knee for knee osteoarthritis with genu varum. Surgical planning was performed so that the target point of the postoperative weight-bearing line (WBL) ratio was 62.5% in preoperative standing and supine radiographs. If the opening gap would be > 13 mm in open-wedge high tibial osteotomy (OWHTO), closed-wedge HTO (CWHTO) was planned. If the postoperative mMPTA would be > 95° in isolated HTO, double-level osteotomy (DLO) was planned. In DLO, lateral closed-wedge distal femoral osteotomy was performed so that the postoperative mechanical lateral distal femoral angle (mLDFA) was 85°, and any residual varus deformity was corrected with HTO. RESULTS: Surgical planning differed between standing and supine radiographs in 43.6% of cases. In all knees for which surgical planning differed between standing and supine radiographs, a more invasive type of osteotomy was suggested by standing radiographs than by supine radiographs. The risk factors for discrepancies in surgical planning were a lower WBL ratio in standing radiographs and a lower joint line convergence angle in supine radiographs. CONCLUSIONS: Surgical planning of DLO, CWHTO and OWHTO, in standing radiographs differed from that in supine radiographs in nearly half of the cases. Surgical planning based on standing radiographs leads to more invasive surgical procedures compared to supine radiographs.