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Clinical Efficacy of Derotational Distal Femoral Osteotomy Combined with Arthroscopic Medial Patellofemoral Ligament Reconstruction for the Treatment of Recurrent Patellar DislocationZhengRu Wu1* ,ChengJian Wu1*, Zhi Chen1,JiaJun Lin1 ,Wenlong Yan2, MD,Aiguo Zhou2 ,ChengJie Lian 1#,Hua Zhang MD1#
Authors
Abstract
Objective:
To assess the clinical efficacy of arthroscopic medial patellofemoral ligament reconstruction (MPFL-R) combined with medial-approach derotational distal femoral osteotomy (DDFO) in the treatment of recurrent patellar dislocation (RPD).
Methods:
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We retrospectively reviewed 45 patients with recurrent patellar dislocation (2 males, 43 females; age 13–44 years, mean 22.8 ± 6.0 years) and a femoral anteversion angle (FAA) > 30°, who underwent combined arthroscopic medial patellofemoral ligament reconstruction (MPFL-R) and medial-approach derotational distal femoral osteotomy (DDFO) at the First Affiliated Hospital of Chongqing Medical University between January 2018 and January 2022. Clinical and radiographic parameters were assessed preoperatively and at a minimum two-year follow-up, including J-sign grading, visual analogue scale (VAS) pain score, Caton–Deschamps index (CD-I), FAA, patellar tilt angle (PTA), tibial tubercle–trochlear groove (TT–TG) distance, and functional scores (Tegner, Kujala, and Lysholm). A subgroup analysis compared outcomes between patients who did and did not undergo adjunctive tibial tubercle osteotomy (TTO).Results:
At the two-year follow-up, patients demonstrated significant improvements in J-sign grading, VAS pain scores, femoral anteversion angle, patellar tilt angle, TT–TG distance, and functional outcomes (Tegner, Kujala, and Lysholm scores) (all P < 0.05). The Caton–Deschamps index showed no significant change (P > 0.05). In subgroup analysis, the TTO cohort experienced a greater reduction in TT–TG distance than the non-TTO cohort (P < 0.05), whereas postoperative VAS, Kujala, and Lysholm scores did not differ significantly between groups (P > 0.05).
Conclusion
Arthroscopic medial patellofemoral ligament reconstruction combined with medial-approach derotational distal femoral osteotomy effectively restores patellofemoral stability and enhances functional outcomes in patients with recurrent patellar dislocation and excessive femoral anteversion. The indication for concomitant tibial tubercle osteotomy should be individualized according to each patient’s specific anatomical and clinical characteristics.
Keywords:
Recurrent patellar dislocation
Femoral anteversion angle
derotational distal femoral osteotomy
Medial patellofemoral ligament reconstruction
List of abbreviations
RPD
recurrent patellar dislocation
DDFO༚Derotational Distal Femoral Osteotomy༛MPFL༚medial patellofemoral ligament༛FAA༚femoral anteversion angle༛TT-TG༚Tibial Tuberosity–Trochlear Groove༛PTA༚Patellar Tilt Angle
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Introduction
Recurrent patellar dislocation is a common knee disorder whose pathogenesis involves both soft-tissue insufficiency and osseous structural abnormalities [1,2]. Patellar stability depends on the coordinated action of peripatellar muscles and ligaments, among which the medial patellofemoral ligament (MPFL) serves as the primary restraint against lateral patellar displacement. Congenital or acquired factors may compromise MPFL integrity, thereby predisposing the patella to recurrent dislocation [3].
With advances in sports medicine, arthroscopic MPFL reconstruction has become a well-established treatment for recurrent instability. Semitendinosus tendon grafts are widely favored for MPFL reconstruction due to their excellent biomechanical properties, high tensile strength, and minimal donor-site morbidity [4,5]. Meanwhile, derotational distal femoral osteotomy (DDFO) has traditionally been performed via a lateral approach with lateral plating to correct excessive femoral anteversion; however, lateral plate placement can be associated with soft-tissue irritation and suboptimal biomechanics.
To address these limitations, this study is the first to employ a medial approach for DDFO—with the osteotomy plate positioned on the medial cortex—in combination with MPFL reconstruction. We hypothesize that this novel surgical route and implant positioning will further improve patellofemoral stability and functional outcomes in patients with recurrent patellar dislocation and excessive femoral anteversion [23].
However, in patients with pronounced osseous abnormalities—particularly those with excessive femoral anteversion (FAA ≥ 30°)—soft-tissue reconstruction alone frequently fails to address the underlying pathomechanics [6]. Excessive femoral internal rotation not only alters patellar tracking but also increases lateralizing forces on the patella, thereby elevating the risk of recurrent dislocation [7]. Consequently, isolated MPFL reconstruction in this subgroup may be insufficient to resolve patellar instability at its root [8].
To further improve clinical outcomes, recent studies have investigated combined strategies of soft-tissue reconstruction and bony realignment. Derotational distal femoral osteotomy (DDFO) has emerged as an effective method for correcting femoral rotational deformity [9,10]. By restoring normal femoral rotation, DDFO re-establishes physiologic patellofemoral biomechanics, creating a more favorable environment for MPFL reconstruction. The synergistic application of these techniques shows promise in reducing dislocation recurrence and achieving comprehensive correction of both soft-tissue and bony pathologies [11,12]. Notably, no prior studies have evaluated a medial-approach DDFO combined with MPFL reconstruction.
Nevertheless, the indication for an additional tibial tubercle osteotomy (TTO) following derotational distal femoral osteotomy (DDFO) remains controversial. Some studies suggest that TTO can further reduce the TT–TG distance and lateral patellar pressure, thereby more effectively preventing recurrence [13,14]. Conversely, other evidence shows no significant differences in postoperative VAS, Kujala, or Lysholm scores between patients with and without TTO, while noting that the added osteotomy may increase surgical trauma, prolong rehabilitation, and elevate the risk of complications [15,16]. Therefore, the decision to perform TTO should be individualized, taking into account each patient’s bony alignment parameters, the quality of soft-tissue reconstruction, and intraoperative biomechanical assessment.
The present study aims to evaluate the clinical efficacy and safety of arthroscopic semitendinosus-autograft MPFL reconstruction combined with a medial-approach DDFO in patients with recurrent patellar dislocation and excessive femoral anteversion (FAA ≥ 30°). We systematically compared preoperative and two-year postoperative pain scores, functional outcomes, radiographic measurements, and patellar tracking, and conducted a subgroup analysis to assess the role of adjunctive TTO. Our goal is to provide evidence-based guidance for optimizing individualized surgical planning.
Materials and Methods
1. Study Population
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From January 2018 to January 2022, we retrospectively reviewed patients admitted to the Department of Orthopaedics at the First Affiliated Hospital of Chongqing Medical University for recurrent patellar dislocation who underwent combined arthroscopic MPFL reconstruction and medial-approach derotational distal femoral osteotomy (DDFO).Inclusion criteria
1.History of ≥ 2 patellar dislocations.2.Preoperative J-sign grade ≥ 2.3.Femoral anteversion angle (FAA) > 30°.4.Received combined DDFO + MPFL reconstruction via a medial approach.5.Minimum postoperative follow-up ≥ 24 months.
Exclusion criteria:1.Revision surgery cases.2.Generalized joint hyperlaxity (Beighton score > 5/9).3.Concomitant multi-ligamentous or osseous knee injuries.4. Cases combined with patella alta/baja or trochleoplasty procedures.
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2. Imaging Protocol and MeasurementsAll patients underwent the following imaging before surgery:Standard anteroposterior and lateral knee radiographs, Full-length, weight-bearing lower-limb radiographs, Merchant (skyline) patellar view, Continuous CT scan from hip to ankle with three-dimensional reconstruction, Using these studies, the following parameters were measured:
Tibial Tubercle–Trochlear Groove (TT–TG) Distance
Overlay the axial CT slice at the proximal femoral trochlea with the slice at the tibial tubercle.Draw the posterior condylar line of the femur as the reference.Mark the lowest point of the trochlear groove and the midpoint of the tibial tubercle, project both onto the reference line, and measure the distance between them.
Femoral Anteversion Angle (FAA)
On the 3D reconstruction, identify the femoral head center and the anterior and posterior boundaries of the femoral neck.Draw the femoral neck axis (line through head center and neck midpoint) and the posterior condylar tangent of the distal femur.The angle between these two lines is recorded as the FAA.
Caton–Deschamps Index (CD-I)
On lateral radiograph, measure the ratio of the distance from the distal articular pole of the patella to the anterior edge of the tibial plateau, divided by the patellar articular length.A normal CD-I ranges from 0.8 to 1.2. Values < 0.8 indicate patella alta; >1.2 indicate patella baja.
Patellar Tilt Angle (PTA)
On axial CT reconstruction of the knee, draw a line connecting the lateral facets of the patella and a line tangent to the lateral trochlear facet.The angle between these two lines represents the PTA.All radiographic measurements were performed independently by two fellowship-trained orthopaedic surgeons; mean values were used for analysis. Continuous variables are reported as mean ± standard deviation.
Surgical Technique
Medial Patellofemoral Ligament Reconstruction
All 45 patients underwent arthroscopic MPFL reconstruction using a semitendinosus autograft. After graft harvest and preparation, the femoral tunnel was drilled at the Schöttle point under fluoroscopic guidance. The graft was secured in the femoral tunnel with an absorbable interference screw. On the patellar side, two suture anchors were placed: one at the midpoint of the medial patellar border and one at the junction of the proximal third and midpoint. The graft limbs were tensioned and fixed to these anchors to restore medial patellar restraint.
Medial-Approach Derotational Distal Femoral Osteotomy
Through extension of the MPFL incision proximally by approximately 8 cm, a medial longitudinal approach was used to expose the distal femur. Subcutaneous tissues and the medial fascia were incised, and the vastus medialis muscle was elevated subperiosteally. The intermuscular septum was carefully released to expose the medial femoral shaft. Blunt retractors were placed to protect the posterior neurovascular structures.
Under fluoroscopic control, the planned osteotomy line was marked on the femur, ensuring it was perpendicular to the mechanical axis in the coronal plane to avoid postoperative varus or valgus malalignment. A custom angular guide was used to preset the derotation angle, targeting a postoperative femoral anteversion of 15°. Two Kirschner wires were inserted proximal to the osteotomy site, diverging at 20° as measured by the guide, and a third distal wire was placed to maintain rotation control.
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Using an oscillating saw and osteotome, a complete transverse osteotomy was performed. The distal femoral segment was then rotated around the K-wire “axis” until the femoral anteversion measured 15°(Fig. 1& 2), as confirmed by the preset guide. Fixation was achieved with an anatomically contoured medial plate and screws. Final fluoroscopic images confirmed restoration of alignment without residual varus or valgus deformity༈Fig. 3& 4༉.Figs. 1
& 2 illustrate the intraoperative placement of the medial plate and the use of Kirschner wires for positioning. Once the desired rotation angle is confirmed, the distal femur is derotated and fixed.
Figs. 3
& 4 show the postoperative anteroposterior and lateral radiographs of the knee following medial-approach derotational osteotomy.
1.4 Postoperative Rehabilitation
All patients followed the same standardized rehabilitation protocol. Beginning on postoperative Day 1, under the guidance of a physiotherapist, passive range-of-motion exercises were initiated. Knee flexion was gradually increased within the patient’s tolerance until full flexion was achieved. Isometric quadriceps contractions also commenced on Day 1 to prevent postoperative quadriceps atrophy. For the first 6 weeks, patients were non-weight-bearing with the aid of two crutches. At 6 weeks, partial weight-bearing was allowed, transitioning gradually to full weight-bearing thereafter.
Preoperative and Postoperative Knee Joint Assessment
Symptom Evaluation and Clinical Examination
The same surgical team, physiotherapists, and follow-up clinicians performed comprehensive knee assessments at the following time points: preoperatively, and at 3 months, 6 months, 1 year, 18 months, and 2 years postoperatively. Evaluations included:1.Radiographic and CT Measurements:TT–TG distance, FAA, patellar tilt angle, and Caton–Deschamps index were measured on three-dimensional CT reconstructions of the lower limb and on standard anteroposterior and lateral knee radiographs.2.Scoring Systems:VAS (Visual Analog Scale): Assessed pain intensity.Kujala Score, Tegner Activity Scale, and Lysholm Score: Evaluated patient-reported outcomes related to pain, activity level, and knee function.
Statistical Analysis
All statistical analyses were performed using SPSS Statistics version 27.0 (IBM Corp., Armonk, NY, USA). Continuous variables—including femoral anteversion angle, patellar tilt angle, TT–TG distance, Caton–Deschamps index, Kujala score, Tegner activity score, and Lysholm score—are presented as mean ± standard deviation. The distribution of each variable was assessed for normality and homogeneity of variance. For comparisons between preoperative and 2-year postoperative values, a paired Student’s t-test was applied to normally distributed data with equal variances; when these assumptions were not met, the nonparametric Mann–Whitney U test was used. A two-tailed P-value < 0.05 was considered statistically significant.
2. Results
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A total of 45 patients (2 male, 43 female) with recurrent patellar dislocation were included in this retrospective series. The median age at the time of surgery was 23 years (range, 13–44 years). Preoperative radiographic assessment demonstrated the following median (range) values: Caton–Deschamps index, 1.03 (0.77–1.20); femoral anteversion angle (FAA), 34.3° (30.1°–38.5°); patellar tilt angle (PTA), 29.0° (22°–36°); and tibial tubercle–trochlear groove (TT–TG) distance, 23.2 mm (20.6–25.9 mm) (Table 1). These baseline measurements confirm significant osseous and patellofemoral alignment abnormalities, providing a benchmark for surgical correction and subsequent outcome evaluation.At a minimum follow-up of two years, patients demonstrated significant improvements in knee stability, pain, alignment, and functional outcomes (Table 2). The J-sign grade declined from 2.11 ± 0.32 preoperatively to 0.27 ± 0.50 at two years (P < 0.05). The VAS pain score improved from 3.67 ± 0.95 to 1.73 ± 0.72 (P < 0.05). Radiographically, the femoral anteversion angle (FAA) was corrected from 34.24° ± 2.33° to 15.19° ± 1.75° (P < 0.05), the patellar tilt angle (PTA) from 28.78° ± 2.95° to 18.04° ± 1.93° (P < 0.05), and the TT–TG distance from 23.44 ± 1.25 mm to 14.78 ± 3.03 mm (P < 0.05). Functional scores also improved markedly: the Tegner activity score increased from 4.00 ± 1.27 to 7.22 ± 0.79 (P < 0.05), the Kujala score from 63.22 ± 6.36 to 89.91 ± 4.84 (P < 0.05), and the Lysholm score from 57.18 ± 6.80 to 85.09 ± 8.81 (P < 0.05). The Caton–Deschamps index remained essentially unchanged (1.03 ± 0.11 vs. 1.04 ± 0.10; P > 0.05).
Subgroup Analysis (Table 3): In the subgroup analysis comparing patients who did and did not undergo tibial tubercle osteotomy (TTO), there were no significant between-group differences in J-sign grade, VAS pain score, femoral anteversion angle (FAA), patellar tilt angle (PTA), Tegner activity score, Kujala score, or Lysholm score (all P > 0.05). However, the TT–TG distance was significantly lower in the TTO group than in the non-TTO group (12.24 ± 0.83 mm vs. 17.97 ± 1.25 mm; P < 0.05).
All surgical incisions healed by primary intention, and no complications—such as knee joint stiffness, infection, or recurrent patellar dislocation—were observed.
Value | |
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Age at time of primary surgery y, median (range) | 23(13–44) |
Sex (Male/Female) | 2/43 |
CD-I ± SD, median (range) | 1.03(0.77–1.20) |
FAA ± SD, median (range) | 34.3(30.1–38.5) |
PTA ± SD, median (range) | 29.0(22–36) |
TT-TG ± SD, median (range) | 23.2(20.6–25.9) |
Preoperatively. | 2years postoperatively. | P-value | |
|---|---|---|---|
J-Sign | 2.11 ± 0.32 | 0.27 ± 0.50 | < 0.05* |
VAS, Mean ± SD | 3.67 ± 0.95 | 1.73 ± 0.72 | < 0.05* |
CD-I ± SD | 1.03 ± 0.11 | 1.04 ± 0.10 | > 0.05 |
FAA ± SD | 34.24 ± 2.33 | 15.19 ± 1.75 | < 0.05* |
PTA ± SD | 28.78 ± 2.95 | 18.04 ± 1.93 | < 0.05* |
TT-TG ± SD | 23.44 ± 1.25 | 14.78 ± 3.03 | < 0.05* |
Tegner ± SD | 4.00 ± 1.27 | 7.22 ± 0.79 | < 0.05* |
Kujala ± SD | 63.22 ± 6.36 | 89.91 ± 4.84 | < 0.05* |
Lysholm ± SD | 57.18 ± 6.80 | 85.09 ± 8.81 | < 0.05* |
Without OTT(20) | With OTT(25) | P-value | |
|---|---|---|---|
J-Sign | 0.25 ± 0.44 | 0.28 ± 0.54 | > 0.05 |
VAS, Mean ± SD | 1.65 ± 0.75 | 1.80 ± 0.71 | > 0.05 |
CD-I ± SD | 1.08 ± 0.11 | 1.02 ± 0.09 | > 0.05 |
FAA ± SD | 15.29 ± 1.57 | 15.11 ± 1.94 | > 0.05 |
PTA ± SD | 17.85 ± 2.50 | 18.20 ± 1.41 | > 0.05 |
TT-TG ± SD | 17.97 ± 1.25 | 12.24 ± 0.83 | < 0.05* |
Tegner ± SD | 7.15 ± 0.88 | 7.28 ± 0.74 | > 0.05 |
Kujala ± SD | 88.90 ± 6.44 | 90.72 ± 3.09 | > 0.05 |
Lysholm ± SD | 84.20 ± 9.08 | 85.8 ± 8.90 | > 0.05 |
Discussion
In this retrospective cohort of 45 patients with recurrent patellar dislocation and a femoral anteversion angle ≥ 30°, all underwent combined arthroscopic MPFL reconstruction and medial-approach derotational distal femoral osteotomy secured with a medial plate. At a minimum two-year follow-up, there were statistically significant improvements in J-sign grading, VAS pain scores, femoral anteversion angle, patellar tilt angle, TT–TG distance, and functional outcomes (Tegner, Kujala, and Lysholm scores), whereas the Caton–Deschamps index remained essentially unchanged. These results indicate that this combined technique not only effectively restores patellofemoral stability, relieves knee pain, and enhances joint function, but also preserves patellar height with high accuracy. Moreover, all incisions healed by primary intention, and no patients developed knee stiffness, wound infection, or recurrent dislocation, underscoring the safety and reliability of this surgical strategy.
The observed improvements in all clinical parameters can be attributed to the synergistic effects of soft-tissue reconstruction and bony realignment achieved by MPFL reconstruction and DDFO [10,21,22]. Specifically, MPFL reconstruction restores medial restraint, effectively counteracting lateral patellar translation [21], while DDFO corrects excessive femoral internal rotation, optimizes patellar tracking, and fundamentally reduces both the TT–TG distance and patellar tilt angle, thereby enhancing the biomechanical stability of the knee joint [10,22].Notably, using a medial plate in this technique confers several additional advantages:Soft-tissue preservation:
The medial plate is inserted through the same medial incision, minimizing soft-tissue dissection and preserving periosteal blood supply. Its low-profile design reduces local friction and inflammatory response, promoting faster and higher-quality osteotomy healing [14].Reduced surgical trauma and complications:Compared with traditional lateral or anteromedial plating, medial-plate fixation via a smaller incision and precise implant positioning simplifies the procedure and shortens operative time. This approach lowers the risk of postoperative wound infection and local pain, and facilitates subsequent plate removal, thereby reducing both intraoperative and postoperative complication rates [16,17,23].
In this cohort, although the majority of patients experienced significant improvements following combined MPFL reconstruction and medial-approach DDFO, 12 patients remained with a residual Grade 1 J-sign [19]. This persistence is likely attributable to insufficient trochlear congruence [20]. The morphology and depth of the femoral trochlea are critical determinants of patellar tracking and stability throughout knee flexion and extension [20]. When the reconstructed medial soft-tissue restraint does not perfectly match the native trochlear geometry, the patella may continue to track suboptimally despite correction of osseous and soft-tissue abnormalities, resulting in a mild residual J-sign [18]. Moreover, interindividual anatomical variability, limitations in intraoperative assessment and fine-tuning of trochlear morphology, and the inherent constraints of medial plating fixation may further compromise postoperative patellotrochlear alignment [17]. Future studies should emphasize precise intraoperative evaluation of trochlear shape—and consider adjunctive trochleoplasty when indicated—to optimize patellar kinematics, minimize residual J-sign incidence, and further enhance overall clinical outcomes [21].
This study further evaluated the impact of adjunctive tibial tubercle osteotomy (TTO) on postoperative outcomes. Subgroup analysis revealed that patients undergoing TTO achieved a significantly lower postoperative TT–TG distance compared with those who did not (12.24 ± 0.83 mm vs. 17.97 ± 1.25 mm; P < 0.05), indicating that TTO further optimizes patellar alignment by reducing TT–TG. However, no significant differences were observed between the TTO and non-TTO groups in Tegner activity score, Kujala score, Lysholm score, or other functional measures (all P > 0.05), suggesting that additional TT–TG reduction after DDFO may not confer further functional benefit. Therefore, in individualized surgical planning, the indication for adjunctive TTO should be carefully considered to avoid unnecessary morbidity.
Conclusion
This study demonstrates that combined MPFL reconstruction and medial-approach derotational distal femoral osteotomy (DDFO) effectively improves knee stability and function in patients with recurrent patellar dislocation and a femoral anteversion angle ≥ 30°. The need for supplementary tibial tubercle osteotomy (TTO) should be evaluated with caution.
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Funding:
No Funding
Human Ethics and Consent to Participate declarations: This study was conducted in accordance with the ethical standards of the 1964 Declaration of Helsinki and its later amendments.
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The study protocol was reviewed and approved by the Clinical Research Committee of the First Affiliated Hospital of Chongqing Medical University (Approval No.: K2023-576). A
Written informed consent was obtained from all individual participants included in the study.Consent for publication
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Consent for publication was obtained.A
Data Availability
The datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.
Competing interests
The authors declare that they have no competing interests.
Funding
This research received no external funding.
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Author Contribution
All authors contributed to the study conception and design. Material preparation and data collection were performed by Chengjian Wu (CW), Zhi Chen (ZC), Jiajun Lin (JL), Wenlong Yan (WY), and Aiguo Zhou (AZ). Statistical analysis was conducted by Zhengru Wu (ZW). The first draft of the manuscript was written by Zhengru Wu (ZW), and revised by Chengjie Lian (CL) and Hua Zhang (HZ). Chengjie Lian (CL) and Hua Zhang (HZ) provided theoretical support and critical revision of the manuscript. All authors commented on previous versions of the manuscript, and all authors read and approved the final manuscript.
Acknowledgements
Not applicable.
Authors’ information
Zhengru Wu1*, Chengjian Wu1*, Zhi Chen1, Jiajun Lin1, Wenlong Yan2, MD, Aiguo Zhou2, Chengjie Lian1#, Hua Zhang1#, MD
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Figures 1 & 2
illustrate the intraoperative placement of the medial plate and the use of Kirschner wires for positioning. Once the desired rotation angle is confirmed, the distal femur is derotated and fixed.
Figures 3 & 4
show the postoperative anteroposterior and lateral radiographs of the knee following medial-approach derotational osteotomy.
Table 1. Patient characteristics
Value | |
|---|---|
Age at time of primary surgery y, median (range) | 23(13–44) |
Sex (Male/Female) | 2/43 |
CD-I ± SD, median (range) | 1.03(0.77–1.20) |
FAA ± SD, median (range) | 34.3(30.1–38.5) |
PTA ± SD, median (range) | 29.0(22–36) |
TT-TG ± SD, median (range) | 23.2(20.6–25.9) |
Table 2 Changes in various indicators within each group of patients before surgery and at 2years postoperatively.
Preoperatively. | 2years postoperatively. | P-value | |
|---|---|---|---|
J-Sign | 2.11 ± 0.32 | 0.27 ± 0.50 | < 0.05* |
VAS, Mean ± SD | 3.67 ± 0.95 | 1.73 ± 0.72 | < 0.05* |
CD-I ± SD | 1.03 ± 0.11 | 1.04 ± 0.10 | > 0.05 |
FAA ± SD | 34.24 ± 2.33 | 15.19 ± 1.75 | < 0.05* |
PTA ± SD | 28.78 ± 2.95 | 18.04 ± 1.93 | < 0.05* |
TT-TG ± SD | 23.44 ± 1.25 | 14.78 ± 3.03 | < 0.05* |
Tegner ± SD | 4.00 ± 1.27 | 7.22 ± 0.79 | < 0.05* |
Kujala ± SD | 63.22 ± 6.36 | 89.91 ± 4.84 | < 0.05* |
Lysholm ± SD | 57.18 ± 6.80 | 85.09 ± 8.81 | < 0.05* |
Table 3. Subgroup Analysis of Differences Between Patients With and Without Tibial Tubercle Osteotomy
Without OTT(20) | With OTT(25) | P-value | |
|---|---|---|---|
J-Sign | 0.25 ± 0.44 | 0.28 ± 0.54 | > 0.05 |
VAS, Mean ± SD | 1.65 ± 0.75 | 1.80 ± 0.71 | > 0.05 |
CD-I ± SD | 1.08 ± 0.11 | 1.02 ± 0.09 | > 0.05 |
FAA ± SD | 15.29 ± 1.57 | 15.11 ± 1.94 | > 0.05 |
PTA ± SD | 17.85 ± 2.50 | 18.20 ± 1.41 | > 0.05 |
TT-TG ± SD | 17.97 ± 1.25 | 12.24 ± 0.83 | < 0.05* |
Tegner ± SD | 7.15 ± 0.88 | 7.28 ± 0.74 | > 0.05 |
Kujala ± SD | 88.90 ± 6.44 | 90.72 ± 3.09 | > 0.05 |
Lysholm ± SD | 84.20 ± 9.08 | 85.8 ± 8.90 | > 0.05 |
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