Abstract
Purpose
The purpose of the study was to report the clinical, functional and radiological outcome following varus osteotomy as a salvage procedure in young to middle-aged patients with patellofemoral arthritis (PFA) and associated valgus malalignment. It was hypothesized that a significant improvement in knee function and reduction in pain would be achieved. Moreover, no conversion to patellofemoral joint arthroplasty could be observed.
Material and methods
Patients (< 50 years of age) that underwent varus osteotomy between 08/2012 and 01/2020 for the treatment of symptomatic PFA and associated valgus malalignment were consecutively included (minimum follow-up: 24 months). Patient-reported outcome measures (PROM; International Knee Documentation Committee subjective knee form [IKDC]), Visual Analog Scale [VAS] for pain, Tegner Activity Scale [TAS], and satisfaction with the postoperative results (1–10-scale, 10 = highest satisfaction) and weight-bearing whole-leg anteroposterior radiographs were conducted pre- and postoperatively. The change in PROM and femorotibial angle (FTA) were tested for statistical significance.
Results
In total, 12 patients (14 knees) were included (66.7% female; mean age: 33.8 ± SD 6.6 years). In ten cases, lateral opening-wedge distal femoral osteotomies (DFO) were performed, of which three cases included a concomitant femoral derotation. Three medial closing-wedge DFO and one medial closing-wedge high tibial osteotomy were performed. At follow-up (55.3 ± 29.3 months), a significant improvement in knee function (IKDC: 56.4 ± 14.4 to 69.1 ± 11.2, p = 0.015) and reduction in pain (VAS for pain: 3.5 [interquartile range 2.3–5.8] to 0.5 [0–2.0], p = 0.018) were observed. Patients were able to reach their preoperative sporting activity level (TAS: 3.0 [3.0–4.0] to 3.5 [3.0–4.0], p = 0.854) and were highly satisfied with the postoperative result (9.0 [6.5–10]). Additionally, a significant correction of valgus malalignment was observed (5.0° ± 2.9° valgus to 0.7° ± 3.2° varus, p < 0.001). Regarding complications, two re-osteosyntheses were performed due to loss of correction and delayed union. No conversion to patellofemoral arthroplasty occurred.
Conclusion
In patients with symptomatic PFA and associated valgus malalignment, varus osteotomy as a salvage procedure achieved a significant improvement in knee function and reduction in pain. No conversion to patellofemoral joint arthroplasty occurred at short- to mid-term follow-up.
Level of evidence
Retrospective case series, Level IV.
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Introduction
Lateral patellar facetectomy [7], lateral retinaculum lengthening [30], patellofemoral arthroplasty [1, 8, 15, 16, 32], and joint-preserving osteotomies, such as anteromedialization tibial tubercle osteotomy [2], are widely accepted surgical treatment options for patients with symptomatic patellofemoral arthritis (PFA) [20]. Although the etiology of PFA is still debated, PFA is most often found on the lateral aspect of the patellar facet and the corresponding area of the trochlea, and may develop secondary to osteochondral injuries, trochlear dysplasia and/or lateral patellar instability [13, 34]. Common risk factors for the onset of PFA include increasing age, female gender, greater BMI, and coronal malalignment [5, 10, 24, 37].
As coronal limb malalignment is a modifiable risk factor for the onset of PFA, alignment-correcting osteotomies have been proposed to delay the progression of PFA [5]. Following valgus correction in the case of symptomatic patellofemoral instability, an improvement or no progression of cartilage deterioration has been reported [27], which may imply that isolated valgus-correcting osteotomies may be a viable salvage procedure for the treatment of PFA in patients with valgus malalignment. Therefore, varus-producing osteotomies may be an alternative to arthroplasty, particularly in younger patients.
The purpose of this study was to report on the clinical, functional and radiological outcome of patients undergoing varus osteotomy for the treatment of symptomatic PFA and associated valgus malalignment. It was hypothesized that a valgus-correcting osteotomy would lead to a significant improvement in subjective knee function and reduction in pain at short- to mid-term follow-up. Furthermore, an adequate correction of valgus malalignment and a low complication rate would be observed.
Material and methods
The presented study was approved by the ethics committee of the Technical University of Munich (reference: 2022-178-S) and conducted according to the Declaration of Helsinki. All patients signed written and informed consent forms. Patients (< 50 years of age) that underwent a varus osteotomy for the treatment of PFA between August 2012 and January 2020 at our institution were eligible to participate minimum 24 months postoperatively. Patients with symptomatic lateral knee osteoarthritis and those who underwent a procedure that aimed to address patellofemoral instability and/or patellofemoral arthroplasty were excluded. Patellofemoral arthroplasty was usually reserved for patients aged > 40 years with end-stage PFA and absence of coronal malalignment [13].
Radiological parameter measurement and surgical planning
Preoperative imaging included magnetic resonance imaging (MRI) of the knee and weight-bearing whole-leg anteroposterior as well as lateral knee radiographs. In nine patients (11 knees) with suspected torsional deformities, either through physical examination or weight-bearing whole-leg anteroposterior radiographs, lower extremity MRI was performed additionally. In our clinical practice, weight-bearing whole-leg anteroposterior radiographs were repeated following alignment-correcting procedures once full weight-bearing is achieved.
The tibial tuberosity–trochlear groove (TT–TG) distance and degree of trochlear dysplasia according to Dejour [25] were evaluated on preoperative MRI. An increased TT–TG was defined as > 20 mm. Type B and D trochlear dysplasias were classified as high-grade [28]. Patellar height was evaluated on lateral knee radiographs and classified using the Caton–Deschamps index with values ≥ 1.2 indicating a patella alta and values ≤ 0.6 indicating a patella infera [6]. For the pre- and postoperative analysis of coronal limb alignment, the femorotibial angle (FTA), mechanical lateral distal femoral angle (mLDFA), and mechanical medial proximal tibial angle (mMPTA) were analyzed on weight-bearing whole-leg anteroposterior radiographs using the medical software mediCAD® (accuracy: 0.01°; mediCAD Hectec GmbH, Altdorf, Germany) according to the method proposed by Strecker [36]. In patients that underwent lower extremity MRI, lower extremity torsion was evaluated according to the method described by Schneider et al. [35]. Due to different surgeons involved in clinical care, the cut-off for a derotational osteotomy usually varied between > 15° and > 20° of femoral antetorsion [12, 18].
A varus osteotomy was indicated in patients with symptomatic PFA and valgus malalignment ≥ 3°. This threshold may have been slightly lower in patients for which a correction of increased femoral antetorsion was performed concomitantly.
Surgical technique
The type of varus-producing osteotomy performed was based on the underlying bony deformity, as described by Dror Paley [31], as well as an individual risk factor analysis.
In patients with femoral deformities, a biplanar supracondylar osteotomy consisting of an osteotomy in the axial and frontal plane of the distal femur was performed via a standardized medial or lateral subvastus approach by experienced sports orthopaedic surgeons. A closing-wedge technique was used in medial osteotomies, whereas an opening-wedge technique was utilized in lateral osteotomies. A medial closing-wedge technique was preferred in patients with a higher risk for delayed union (nicotine abuse, high BMI) [22]. In cases with concomitant torsional deformities, a lateral opening-wedge technique was utilized, as described previously [11, 12]. An internal plate fixator system with locking screws was used (TomoFix® medial/lateral distal femur plate, DePuy Synthes, Umkirch, Germany) for the fixation of the osteotomy, see Fig. 1. Bone grafting of the osteotomy gap was not performed.
In patients with tibial deformities, a biplanar osteotomy in the axial and frontal plane of the proximal tibia was performed via a standardized medial approach. The tibial tubercle was osteotomized distally as to avoid progression of PFA, as recommended in current literature [14, 29]. An internal plate fixator system with locking screws was used (TomoFix® medial high tibia plate, DePuy Synthes, Umkirch, Germany) for the fixation of the osteotomy. The tibial tubercle was fixed using two bicortical screws.
The aim was to achieve neutral alignment in all osteotomies.
Postoperative rehabilitation
Postoperatively, partial weight bearing (20 kg) was allowed for 6 weeks. After a check-up 6 weeks postoperatively, full weight-bearing was encouraged. Physical therapy started on the first postoperative day with passive flexion with patients undergoing treatments 2–3 times per week. Resumption of daily and sporting activities was recommended after 3 months.
Outcome assessment
Validated patient-reported outcome measures (PROM; International Knee Documentation Committee subjective knee form (IKDC), Visual Analog Scale [VAS] for pain, Tegner Activity Scale [TAS], subjective satisfaction with the postoperative result [1–10 scale, 10 = highest satisfaction]) were collected pre- and minimum 24 months postoperatively [4]. Return to sporting activities as well as the Kujala score were evaluated at follow-up. Patients were additionally asked whether they would undergo the same procedure again.
Furthermore, demographic factors and patient records with a special focus on revision and conversion to patellofemoral arthroplasty were analyzed.
Statistical analysis
Data were analyzed using SPSS 26.0 (IBM-SPSS, New York, USA). Categorical variables are presented in counts and percentages. Normal distribution of the collected continuous variables was assessed by the Shapiro–Wilk test and graphically confirmed. Normally distributed continuous variables are shown as mean ± standard deviation. Non-normally distributed continuous variables are shown as median (25–75% interquartile range). For group comparisons of continuous variables, the Wilcoxon test or t test was applied. Statistical significance was set at a p value of < 0.05.
Due to the rarity of this pathology and the small sample size, all treated subjects were included and a power analysis was not conducted.
Results
In total, varus osteotomies were performed on 13 patients (15 knees) for the treatment of PFA and associated valgus malalignment between August 2012 and January 2020. Twelve of those patients (66.7% female; 14 knees) were followed-up (92.3%). The remaining patient was excluded from all analyses as no follow-up data were available. At index surgery, patients were 33.8 ± 6.6 years old. Follow-up examinations were conducted 55.3 ± 29.3 months postoperatively. Six patients (50%) reported a history of patellofemoral instability, but patellofemoral pain was the governing symptom in all patients who underwent varus osteotomy.
Radiological parameters
An increased TT–TG distance was present in one patient (8.3%), who underwent a concomitant medialization of the tibial tubercle. A patella alta was found in three patients (25.0%), whereas no patient had a patella infera. High-grade trochlear dysplasia was observed in five patients (41.7%).
From pre- to postoperatively, mFTA changed significantly (5.0° ± 2.9° valgus to 0.7° ± 3.2° varus, p < 0.001).
Surgical procedures
Ten lateral open-wedge distal femoral osteotomies (DFO) were performed (71.4%). In three of those knees with a mean femoral anteversion of 21.0° ± 4.9°, the osteotomies also aimed to correct femoral antetorsion. Furthermore, three medial closing-wedge DFO (21.4%) and one medial closing-wedge high tibial osteotomy (7.1%) were performed. Concomitant procedures were performed in five knees (35.7%) that underwent DFO, see Table 1. By follow-up, implant removals were performed in 12 knees (85.7%).
Clinical and functional outcome
At follow-up, a significant improvement in knee function (IKDC: 56.4 ± 14.4 to 69.1 ± 11.2, p = 0.015) and reduction in pain (VAS for pain: 3.5 [2.3–5.8] to 0.5 [0–2.0], p = 0.018) were observed, see Fig. 2. Overall, patellofemoral symptoms were low at follow-up (Kujala score: 87.0 [62.0–92.0] and patients reached the same sporting activity level as preoperatively (TAS: 3.0 [3.0–4.0] to 3.5 [3.0–4.0], p = 0.854), see Fig. 3.
Nine patients (75.0% of all included patients) responded to an additional survey on return to sport and work data as well as satisfaction with the postoperative result. Seven patients (77.8%) reported preoperative limitations in their sporting ability. In these patients, sporting ability increased postoperatively in five (55.6%), decreased in one (11.1%) and remained unchanged in three patients (33.3%). Eight patients (88.9%) said that they would undergo the same procedure again. Patients were highly satisfied with the postoperative results (9.0 [6.5–10]). Regarding complications, two re-osteosyntheses were performed 5 and 11 months postoperatively, respectively, due to loss of correction and delayed union. No conversion to patellofemoral arthroplasty or total knee arthroplasty occurred during follow-up.
Discussion
The most important finding of this study was that patients achieved a significant improvement in knee function and reduction in pain following a valgus-correcting osteotomy for the treatment of PFA and associated valgus malalignment. Additionally, patients were able to return to moderate activity and were highly satisfied with the postoperative result. In total, two complications occurred (14.3%).
Due to the complexity of each case, the treatment of patients with symptomatic, isolated PFA and associated valgus malalignment is challenging, necessitating an individual, risk factor-based approach. This may explain why literature on this topic is limited. Alignment-correcting osteotomies have previously been utilized in treating patients with patellofemoral pain [9, 23], but data for the treatment of PFA is scarce [3]. To our knowledge, only one study previously assessed the outcome following varus osteotomy in patients with symptomatic patellofemoral and lateral tibiofemoral arthritis and associated valgus malalignment [3]. The authors reported a considerable improvement of knee function and significant medialization of the patella. Extrapolation of their data to patients with isolated PFA may, however, be limited due to the presence of lateral tibiofemoral arthritis in their cohort.
Besides varus osteotomies, tibial tubercle osteotomies have been proposed as a treatment option to correct the pathological Q-angle—responsible for a laterally translated patella, a shifted force on the lateral patellar facet and, ultimately, increased patellofemoral contact pressure [33]. Following tibial tubercle osteotomy, good results have been reported in patients suffering from PFA [2]. Nevertheless, careful patient selection is paramount as tibial tubercle osteotomies correct a pathological Q-angle but not valgus malalignment, which is frequently observed in patients with lateral PFA [5, 24, 37].
Besides an increased Q-angle, it has also been shown that increased femoral antetorsion, which is apparent in 30.2% of valgus knees with osteoarthritis [21], may cause an increase in patellofemoral contact pressure. Consequently, in patients with both valgus malalignment and increased femoral anteversion, a varization may be combined with a derotation. Previous biomechanical studies and computer simulation models have reported the effect of derotational osteotomies on coronal alignment. Through some of those studies, concerns were expressed regarding an unintended valgization [17, 19, 26]. In a previous study on patellofemoral instability associated with valgus malalignment and increased femoral antetorsion, however, the authors were able to show that a combined varization and derotation is feasible and accurate using a biplanar supracondylar femoral osteotomy [12]. Consequently, both whole-leg weight-bearing anteroposterior radiographs and lower extremity MRI should be conducted routinely when treating patients with PFA.
This study has several limitations that must be considered. First, its retrospective nature and lack of a control group should be mentioned. The lack of a control group may, however, be due to the unavailability of alternative treatment options. Second, in five knees (35.7%), concomitant procedures were performed which may have confounded the outcome. Third, different types of osteotomies were utilized which was, however, done in an effort to address the underlying bony deformity [31]. Additionally, different cut-off values for increased femoral antetorsion due to multiple surgeons involved and the long inclusion time frame, which may have confounded the outcomes further. Fourth, the IKDC may not have been optimal to assess patients with patellofemoral disorders. As the IKDC is evaluated during our department’s routine follow-up, it was also evaluated during this study to assess the gain in overall knee function rather than the patellofemoral joint, for which the Kujala score was collected only at follow-up. Furthermore, whereas the mean follow-up of 55.3 ± 29.3 months was sufficient to display the short- to mid-term outcome, it may not have been sufficient to evaluate whether patellofemoral joint arthroplasty can be avoided altogether. Nevertheless, the clinical, functional and radiological outcome was favourable and conversion to patellofemoral arthroplasty was not observed within the follow-up period.
Conclusion
In patients with symptomatic PFA and associated valgus malalignment, varus osteotomy as a salvage procedure achieved a significant improvement in knee function and reduction in pain. No conversion to patellofemoral joint arthroplasty occurred at short-term to mid-term follow-up.
References
Abeysekera WYM, Schenk W (2021) Patient-related outcomes of patellofemoral arthroplasty: experience of a single center. Arthroplasty 3:19
Agarwalla A, Liu JN, Wu HH, Kalbian IL, Garcia GH, Shubin Stein BE (2021) Return to work following tibial tubercle osteotomy for patellofemoral osteoarthritis and pain. Cartilage 13:1066s–1073s
Barnavon T, Odri GA, Vendeuvre T, Labrada-Blanco O, Bordes M, Renard G et al (2020) Medial closing-wedge distal femoral varus osteotomy: symptoms and functional impact in cases of associated patellofemoral osteoarthritis. A two-year follow-up prospective pilot study. Knee 27:615–623
Barroso Rosa S, Grant A, McEwen P (2023) Patient-reported outcome measures for patellofemoral disorders: a systematic review. Arch Orthop Trauma Surg 143:3919–3927
Cahue S, Dunlop D, Hayes K, Song J, Torres L, Sharma L (2004) Varus-valgus alignment in the progression of patellofemoral osteoarthritis. Arthritis Rheum 50:2184–2190
Caton JH, Dejour D (2010) Tibial tubercle osteotomy in patello-femoral instability and in patellar height abnormality. Int Orthop 34:305–309
Douiri A, Lavoué V, Galvin J, Boileau P, Trojani C (2022) Arthroscopic lateral patellar facetectomy and lateral release can be recommended for isolated patellofemoral osteoarthritis. Arthroscopy 38:892–899
Elbardesy H, McLeod A, Gul R, Harty J (2022) Midterm results of modern patellofemoral arthroplasty versus total knee arthroplasty for isolated patellofemoral arthritis: systematic review and meta-analysis of comparative studies. Arch Orthop Trauma Surg 142:851–859
Fluegel J, Zimmermann F, Gebhardt S, Milinkovic DD, Balcarek P (2023) Combined distal femoral osteotomy and tibial tuberosity distalization is effective in patients presenting with patellar instability and patellofemoral pain due to patella alta and femoral malalignment. Arch Orthop Trauma Surg 143:2557–2563
Hart HF, Barton CJ, Khan KM, Riel H, Crossley KM (2017) Is body mass index associated with patellofemoral pain and patellofemoral osteoarthritis? A systematic review and meta-regression and analysis. Br J Sports Med 51:781–790
Hinterwimmer S, Minzlaff P, Saier T, Niemeyer P, Imhoff AB, Feucht MJ (2014) Biplanar supracondylar femoral derotation osteotomy for patellofemoral malalignment: the anterior closed-wedge technique. Knee Surg Sports Traumatol Arthrosc 22:2518–2521
Hinz M, Cotic M, Diermeier T, Imhoff FB, Feuerriegel GC, Woertler K et al (2022) Derotational distal femoral osteotomy for patients with recurrent patellar instability and increased femoral antetorsion improves knee function and adequately treats both torsional and valgus malalignment. Knee Surg Sports Traumatol Arthrosc. https://doi.org/10.1007/s00167-022-07150-9
Hoogervorst P, Arendt EA (2022) Patellofemoral arthroplasty: expert opinion. J Exp Orthop 9:24
Horikawa T, Kubota K, Hara S, Akasaki Y (2020) Distal tuberosity osteotomy in open-wedge high tibial osteotomy does not exacerbate patellofemoral osteoarthritis on arthroscopic evaluation. Knee Surg Sports Traumatol Arthrosc 28:1750–1756
Imhoff AB, Bartsch E, Becher C, Behrens P, Bode G, Cotic M et al (2022) The lack of retropatellar resurfacing at index surgery is significantly associated with failure in patients following patellofemoral inlay arthroplasty: a multi-center study of more than 260 patients. Knee Surg Sports Traumatol Arthrosc 30:1212–1219
Imhoff AB, Feucht MJ, Bartsch E, Cotic M, Pogorzelski J (2019) High patient satisfaction with significant improvement in knee function and pain relief after mid-term follow-up in patients with isolated patellofemoral inlay arthroplasty. Knee Surg Sports Traumatol Arthrosc 27:2251–2258
Imhoff FB, Beitzel K, Zakko P, Obopilwe E, Voss A, Scheiderer B et al (2018) Derotational osteotomy of the distal femur for the treatment of patellofemoral instability simultaneously leads to the correction of frontal alignment: a laboratory cadaveric study. Orthop J Sports Med 6:2325967118775664
Imhoff FB, Cotic M, Liska F, Dyrna FGE, Beitzel K, Imhoff AB et al (2019) Derotational osteotomy at the distal femur is effective to treat patients with patellar instability. Knee Surg Sports Traumatol Arthrosc 27:652–658
Jud L, Vlachopoulos L, Häller TV, Fucentese SF, Rahm S, Zingg PO (2020) The impact of mal-angulated femoral rotational osteotomies on mechanical leg axis: a computer simulation model. BMC Musculoskelet Disord 21:50
Keshmiri A, Dirisamer F, Liebensteiner M, El Attal R, Pagenstert G, Seitlinger G et al (2021) Operative treatment options for patellofemoral arthritis: an expert recommendation of the AGA Patellofemoral Committee. Orthop J Sports Med 9:2325967121994849
Li C, Ye Y, He S, Xu D, He P (2022) High femoral anteversion in osteoarthritic knees, particularly for severe valgus deformity. J Orthop Traumatol 23:38
Liska F, Haller B, Voss A, Mehl J, Imhoff FB, Willinger L et al (2018) Smoking and obesity influence the risk of nonunion in lateral opening wedge, closing wedge and torsional distal femoral osteotomies. Knee Surg Sports Traumatol Arthrosc 26:2551–2557
Liße J, Perl M, Dickschas J (2023) Double-level torsional osteotomy a treatment for the “inwardly pointing knee” syndrome. Arch Orthop Trauma Surg 143:2863–2875
Macri EM, Felson DT, Ziegler ML, Cooke TDV, Guermazi A, Roemer FW et al (2019) The association of frontal plane alignment to MRI-defined worsening of patellofemoral osteoarthritis: the MOST study. Osteoarthr Cartil 27:459–467
Nelitz M, Lippacher S, Reichel H, Dornacher D (2014) Evaluation of trochlear dysplasia using MRI: correlation between the classification system of Dejour and objective parameters of trochlear dysplasia. Knee Surg Sports Traumatol Arthrosc 22:120–127
Nelitz M, Wehner T, Steiner M, Dürselen L, Lippacher S (2014) The effects of femoral external derotational osteotomy on frontal plane alignment. Knee Surg Sports Traumatol Arthrosc 22:2740–2746
Nha KW, Ha Y, Oh S, Nikumbha VP, Kwon SK, Shin WJ et al (2018) Surgical treatment with closing-wedge distal femoral osteotomy for recurrent patellar dislocation with genu valgum. Am J Sports Med 46:1632–1640
Ntagiopoulos PG, Byn P, Dejour D (2013) Midterm results of comprehensive surgical reconstruction including sulcus-deepening trochleoplasty in recurrent patellar dislocations with high-grade trochlear dysplasia. Am J Sports Med 41:998–1004
Ogawa H, Matsumoto K, Yoshioka H, Sengoku M, Akiyama H (2020) Distal tibial tubercle osteotomy is superior to the proximal one for progression of patellofemoral osteoarthritis in medial opening wedge high tibial osteotomy. Knee Surg Sports Traumatol Arthrosc 28:3270–3278
Pagenstert G, Wolf N, Bachmann M, Gravius S, Barg A, Hintermann B et al (2012) Open lateral patellar retinacular lengthening versus open retinacular release in lateral patellar hypercompression syndrome: a prospective double-blinded comparative study on complications and outcome. Arthroscopy 28:788–797
Paley D, Herzenberg JE, Tetsworth K, McKie J, Bhave A (1994) Deformity planning for frontal and sagittal plane corrective osteotomies. Orthop Clin N Am 25:425–465
Pogorzelski J, Rupp MC, Ketzer C, Cotic M, Lutz P, Beeck S et al (2021) Reliable improvements in participation in low-impact sports following implantation of a patellofemoral inlay arthroplasty at mid-term follow-up. Knee Surg Sports Traumatol Arthrosc 29:3392–3399
Ramappa AJ, Apreleva M, Harrold FR, Fitzgibbons PG, Wilson DR, Gill TJ (2006) The effects of medialization and anteromedialization of the tibial tubercle on patellofemoral mechanics and kinematics. Am J Sports Med 34:749–756
Sanders TL, Pareek A, Johnson NR, Stuart MJ, Dahm DL, Krych AJ (2017) Patellofemoral arthritis after lateral patellar dislocation: a matched population-based analysis. Am J Sports Med 45:1012–1017
Schneider B, Laubenberger J, Jemlich S, Groene K, Weber HM, Langer M (1997) Measurement of femoral antetorsion and tibial torsion by magnetic resonance imaging. Br J Radiol 70:575–579
Strecker W (2006) Planning analysis of knee-adjacent deformities. I. Frontal plane deformities. Oper Orthop Traumatol 18:259–272
Weinberg DS, Tucker BJ, Drain JP, Wang DM, Gilmore A, Liu RW (2016) A cadaveric investigation into the demographic and bony alignment properties associated with osteoarthritis of the patellofemoral joint. Knee 23:350–356
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MH and AA designed the study. MW, MB, LF, and AO collected data. MH and AA performed the statistical analysis and wrote the manuscript. SS supported data interpretation and critically reviewed the manuscript. All authors read and approved the final manuscript.
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Maximilian Hinz, Maximilian Weyer, Moritz Brunner, Lorenz Fritsch, Alexander Otto and Andrea Achtnich declare no conflict of interest. Sebastian Siebenlist is a consultant for Arthrex Inc., medi GmbH & Co. KG, Medartis AG, and KLS Martin Group.
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The study was approved by the institutional review board of the Technical University of Munich (reference: 2022-178-S) and the study was performed in accordance with the Declaration of Helsinki.
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Hinz, M., Weyer, M., Brunner, M. et al. Varus osteotomy as a salvage procedure for young patients with symptomatic patellofemoral arthritis and valgus malalignment at short- to mid-term follow-up: a case series. Arch Orthop Trauma Surg 144, 1667–1673 (2024). https://doi.org/10.1007/s00402-024-05212-w
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DOI: https://doi.org/10.1007/s00402-024-05212-w