Distal Realignment Research Articles

A Modified 4-in-1 Stanisavljevic Procedure for Treating Obligatory or Congenital Patellar Dislocations in Children: A Surgical Technique.

Patellar instability and dislocation pose complex clinical and surgical challenges, especially in children. Congenital (fixed) and obligatory (habitual) dislocations present significant anatomical and etiological complexity, frequently leading to deformities and functional impairments, which can range from walking difficulties to sports limitations. Conservative treatment is often inadequate. We describe a surgical technique for treating congenital or obligatory patellar dislocations in patients with various underlying diagnoses-including Down syndrome, nail-patella syndrome, and skeletal dysplasia-that involves extensive subperiosteal quadriceps realignment, distal realignment (Roux-Goldthwait or tibial tuberosity transfer), and optional medial plication. This modified 4-in-1 technique follows the principles described in 1976 by Stanisavljevic, which involves subperiosteal quadriceps mobilization, thus minimizing muscle damage, bleeding, and postoperative muscular adherences. In 24 patients treated at our institution between 2002 and 2021 (35 knees; age range = 5.5-16.8 years; 13 girls, 11 boys), with a mean follow-up of 8.2 years (2.4-20 years), we achieved satisfactory improvements in patellar stability, range of motion, and quality of life with a modified 4-in-1 Stanisavljevic technique. A total of 9 patients (7 with obligatory dislocations and 2 with congenital dislocations) could engage in recreational or competitive sports. The average postoperative pediatric International Knee Documentation Committee (pedi-IKDC) score was 78.45 ± 22.3 (range = 0-100); a patient with DiGeorge syndrome and 1 with multiple epiphyseal dysplasia had scores of 35 and 48, respectively. We found at our institution that a modified 4-in-1 Stanisavljevic technique produced favorable outcomes in patellar stability, range of motion, and quality of life in pediatric patients with congenital or obligatory patellar dislocation. More study is warranted to determine the procedure's overall benefits for children with obligatory or congenital dislocations of complex etiology.

The tibial tubercle-to-trochlear groove distance changes in standing weight-bearing condition: An upright weight-bearing computed tomography analysis

BackgroundThe tibial tubercle-to-trochlear groove (TT-TG) distance and Insall-Salvati (I/S) ratio are widely used to determine the need for distal realignment in conjunction with medial patellofemoral ligament (MPFL) reconstruction in patients with recurrent patellar dislocation. A TT-TG distance >20 mm and an I/S ratio >1.3 are significant anatomical risk factors for patellar instability. However, these parameters have traditionally been measured using non-weight-bearing (NWB) imaging modalities. As patellar dislocation occurs during weight-bearing actions, these two parameters should be measured under weight-bearing conditions. Thus, this study aimed to measure the TT-TG distance and I/S ratio using upright full-weight-bearing (FWB) computed tomography (CT) scans and compare the data with NWB CT scans. MethodsThis study included 49 knee joints of 26 healthy volunteers. CT images were obtained under both FWB and NWB standing conditions using a 320-detector row upright CT scanner. TT-TGs in the axial plane and I/S ratios in the sagittal plane were measured and compared. ResultsThe average FWB TT-TG distance was 20.3 ± 3.9 mm, whereas the average NWB TT-TG distance was 12.3 ± 4.7 mm. The TT-TG level was significantly higher in the FWB condition than that in the NWB condition (P < 0.001). The I/S ratios were comparable between the FWB and NWB conditions (P = 0.29). ConclusionsThe TT-TG distance in the standing weight-bearing condition was larger than the conventional TT-TG distance and surpassed the historical cutoff value of TT-TG, which may affect the indication of additional distal realignment in MPFL reconstruction for patellar instability.

The tibial tubercle-trochlear groove distance: a comparison study between EOS and MRI in the paediatric population.

This study aims to compare the relative reliability and accuracy of TT-TG measurements in EOS with that of MRI in a paediatric population. Patients were included if they underwent both an MRI and EOS scans and were under the age of 16. Two authors recorded the TT-TG distances on each modality at two separate time points. In the EOS images, the distance between the two points was measured in the horizontal 2D plane. In the MRI images, it was done in the plane referenced by posterior femoral condylar axis. The intra- and inter-rater reliability was assessed in each modality and between modalities. Twenty-seven patients (30 knees), 14 males, and 13 females with an average age of 13years (range: 7-16years) were included in the study. The mean TT-TG distance on EOS scan and MRI scan was 14mm. On inter- and intra-observer analysis, both imaging modalities had excellent reliability (0.97 ICC for EOS and 0.98 ICC for MRI inter-observer) and repeatability (0.98-0.99 ICC for EOS and 0.99 ICC for MRI for intra-observer). However, on comparing the two imaging modalities (EOS vs MRI), the ICC was fair (0.56 ICC for rater 1 and 0.65 ICC for rater 2). While the EOS TT-TG measurements were precise and reproducible, they were only moderately comparable to MRI TT-TG measurements. Consequently, EOS TT-TG measurements should not be used for decision-making without the development of EOS-specific TT-TG values that indicate the need for distal realignment surgery. Level II.

Normative Values of Tibial Tubercle–Trochlear Groove Distance and Tibial Tubercle–Posterior Cruciate Ligament Distance in Children

Background: Patellar instability is a common knee pathology in skeletally immature patients. In skeletally mature populations, a tibial tubercle–trochlear groove (TT-TG) distance of ≥20 mm is generally considered a pathological value. However, as pediatric patients grow and as the TT-TG distance varies with age, applying the same cutoff value as adult patients to them is unreasonable. Purpose/Hypothesis: This study aimed to analyze the normative values of the TT-TG and tibial tubercle–posterior cruciate ligament (TT-PCL) distances in children with no patellofemoral instability and to propose the cutoff value of the TT-TG and TT-PCL distances predictive of increased risk of patellofemoral instability in pediatric patients. We hypothesized that the TT-TG and TT-PCL distances increase with age in children and adolescents. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Magnetic resonance imaging scans of the knee were collected from the patellar instability group and the control group. The TT-TG and TT-PCL distances were measured. The normalized values of the TT-TG and TT-PCL distances were calculated by dividing them by the femoral width. Segmented analysis with 1 breakpoint was performed for both the TT-TG and the TT-PCL distances. The optimal cutoff values of the TT-TG and TT-PCL distances were calculated by maximizing the sum of the sensitivity and specificity. Results: A total of 87 patients had patellar instability, and 509 patients did not. The median values of TT-TG and TT-PCL distances in the control group (8.18 mm and 19.48 mm, respectively) were significantly smaller than those in the instability group (16.10 mm and 24.41 mm, respectively). For those aged <15 years, the TT-TG distance significantly increased by 0.39 mm as the age increased by 1 year. The TT-PCL distance increased by 1.14 mm/year until the age of 11 years. In our cohort, the cutoff value of the TT-TG distance of 14.90 mm yielded 66% sensitivity and 81.9% specificity for predicting an increased risk of patellar instability. The cutoff value of the TT-PCL distance of 23.68 mm yielded 63.9% sensitivity and 65.3% specificity for predicting an increased risk of patellar instability. Conclusion: In our cohort of 596 participants, we have documented the normative values of the TT-TG and TT-PCL distances in children aged <20 years. During the surgery for patellar instability in pediatric patients, orthopaedic surgeons should consider the normative values of the TT-TG and TT-PCL distances according to age to determine which patients need distal realignment surgery.

Habitual Patellar Dislocation Treated By Anteromedial Tibial Tubercle Transfer (Fulkerson Osteotomy) with Medial Patellofemoral Ligament Reconstruction Using Superficial Layer of Quadriceps Tendon Autograft: A Case Report

Introduction: Bony malalignment and soft tissue injury of Medial Patellofemoral Ligament (MPFL) in chronic patellar instability is considered as a surgical indication for distal realignment in the form of anteromedial tibial tubercle transfer (Fulkerson osteotomy) with MPFL reconstruction, are effectively unloads the lateral patella while making the patellofemoral joint more congruous, stable and pain free. Method: A 26 years old male with left habitual patellar dislocation and pain on his left knee. The patient underwent Fulkerson osteotomy (Tibial tuberosity elevation osteotomy and medial transfer) and medial patellofemoral ligament (MPFL) reconstruction using superficial layer of quadriceps tendon autograft. The patient underwent arthroscopic examination preoperatively and found cartilage lesion of patella (Outerbridge type III). Conclusion: Fulkerson osteotomy and MPFL reconstruction is a successful procedure to treat habitual patellar dislocation and patellofemoral pain. The Fulkerson osteotomy can improve the patella stability and knee function. MPFL reconstruction using superficial layer of quadriceps tendon was simple and has fewer complication than using other autografts, such as hamstring tendon, adductor tendon, and patellar tendon.

Modified Grammont Soft-Tissue Distal Patellar Realignment and Medial Patellofemoral Ligament Reconstruction for Patellofemoral Instability in Pediatric Patients

Patellar dislocation is a relatively common pediatric injury, which often results in recurrent patellofemoral instability. An increased tibial tubercle–trochlear groove distance predisposes to patellofemoral instability and can be corrected with a distal realignment procedure. Soft-tissue distal realignment procedures must be used in the pediatric population to avoid the risks of premature physeal closure associated with tibial tubercle osteotomies. Several soft-tissue distal realignment procedures have been described, with no consensus as to the optimal technique. When combined with medial patellofemoral ligament reconstruction, distal realignment procedures can restore patellofemoral stability through the entire flexion arc. This article describes a modification of the Grammont distal patellar realignment procedure in conjunction with medial patellofemoral ligament reconstruction for the management of pediatric patellofemoral instability.

Surgical Correction of Non-traumatic Patella Maltracking. Midterm Clinical Follow-up.

BackgroundPatellar instability comprises a group of pathologies that allow the patella to move out of its trajectory within the trochlear groove during walking. Symptomatic patients who need surgery commonly undergo soft tissue procedures such as medial patellofemoral ligament repair to strengthen the ligaments that hold the patella in place. However, soft-tissue repairs may be insufficient in patients suffering from patellar maltracking, which is characterized by an unbalanced gliding of the patella within its route. In these patients, a different approach is advised. We aim to provide the mid-term clinical outcomes of the Fulkerson distal realignment operation in selected patients with non-traumatic patellar maltracking.MethodsThe clinical outcomes of the Fulkerson distal realignment operation performed in 22 knees of 21 patients were evaluated by a self-administered subjective International Knee Documentation Committee (IKDC) score and the Tegner–Lysholm knee scoring scale.ResultsBefore surgery, the median IKDC score was 52, and the median Tegner–Lysholm score was 56. Following surgery (mean follow-up 48 months, range 24–156), the median IKDC and the Tegner–Lysholm scores were 67 and 88, respectively. The improvement was statistically significant (P=0.001 and P=0.002 for IKDC and Tegner–Lysholm scores, respectively). Associated procedures included patella microfracture due to grade III–IV cartilage lesion (International Cartilage Repair Society grading system) in four patients, retinacular releases in three patients, medial capsular augmentations in two patients, and medial patellofemoral ligament reconstruction in two patients. One patient with Ehlers–Danlos disease required excessive medialization of the tibial tuberosity. Surgery-related complications occurred in three patients.DiscussionSurgical correction of patellar maltracking with Fulkerson distal realignment combined with associated procedures in individual patients was associated with an increase in subjective and functional clinical scores at medium-term follow-up. Particular attention should address pathologies associated with patellar maltracking and managed accordingly.Level of evidence4c (case series).

Bioabsorbable magnesium screw fixation for tibial tubercle osteotomy; a preliminary study.

Background and aim:Metallic screws are commonly used to fix tibial tubercle osteotomies (TTO). However, hardware removal late after osteotomy union is one of the most common causes of reoperation following TTOs. The use of bioabsorbable screws may eliminate secondary surgeries, but there is no study on their use in this indication. The purpose of this retrospective study was to evaluate the safety and efficacy of bioabsorbable magnesium (Alloy: MgYREZr) screws in tibial tubercle osteotomy (TTO) fixation.Methods:Ten consecutive patients with objective patellar instability who underwent distal realignment procedure using Fulkerson TTO were retrospectively reviewed. The osteotomy was secured with two parallel 4.8 mm magnesium screws in all patients. Kujala score and Lysholm knee score were used to assess the functional outcomes before and after the operation. During the follow-up, the union of the osteotomy, displacement, and other imaging findings were evaluated with serial knee radiographs.Results:There were five male and five female patients with a mean age of 23.4±9.2 years (range, 15–45). The mean follow-up duration was 11.5±3.2 months (range,6–17 months). The osteotomy united in all cases at an average of 3 months. No infection or wound healing problems were seen. A significant increase in Kujala (p:.005) and Lysholm knee scores (p:.005) were recorded in all patients.Conclusion:Despite a limited number of patients were reviewed, the findings support that bioabsorbable magnesium screws can be safely used as an alternative fixation technique in TTO. Furthermore, it provides the advantage of eliminating the need for implant removal. (www.actabiomedica.it)

Technical Considerations for an Anteromedializing Tibial Tubercle Osteotomy

Background: Tibial tubercle osteotomy and distal realignment allows for adjustment to the patellofemoral articulation in order to improve patellar tracking and redistribute patellar contract pressures. Indications: A healthy, active 39-year-old woman status post right knee tibial tubercle osteotomy presented with &gt;2 years of patellar instability symptoms in the left knee. Imaging revealed a tibial tubercle to trochlear groove (TT-TG) distance of 21 mm and patellar tendon lateral trochlear ridge (PT-LTR) distance of 14 mm. Technique Description: After knee arthroscopy is performed, an open incision is made along the inferomedial patellar tendon. Two pilot holes are created before a sagittal saw is used to make the tibial tubercle osteotomy, before completing it with an osteotome. Anteromedialization and/or distalization of the osteotomy is performed relative to templated values in order to improve patellar articulation. After correction, 3 bicortical screws are placed to achieve stable fixation. Results: There were no immediate complications following surgery. Surgical management led to improvement of the patient’s patellofemoral pain, which allowed return to prior baseline level of function. Discussion/Conclusion: The preferred technique for an anteromedialzing tibial tubercle osteotomy is presented. An anteromedializing tibial tubercle osteotomy is an effective surgical option for patients with evidence of patellar maltracking or central or lateral patellar chondromalacia whom have failed conservative management. This case demonstrates the efficacy of an anteromedializing tibial tubercle osteotomy to provide pain relief by improving patellar tracking and offloading patellar contact pressures on areas of prominent chondral wear.

Chronic patellofemoral instability and pain treated effectively by anteromedial tibial tubercle transfer (Fulkerson osteotomy) with or without medial patellofemoral ligament reconstruction

&lt;p&gt;&lt;strong&gt;Background&lt;/strong&gt;-Chronic patellar instability (subluxation and dislocation) and pain is a debilitating knee condition that frequently involves young, active patients. Bony malalignment and soft tissue injury (torn or stretched MPFL) is considered as a surgical indication for distal realignment in the form of Anteromedial tibial tubercle transfer(Fulkerson osteotomy) with or without MPFL reconstruction that effectively prevents the patella from tracking laterally and thus unloads the lateral patella while making the patellofemoral joint more congruous , stable and pain free.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Materials and method&lt;/strong&gt; - It is a prospective study of 22 patients of chronic patellar instability and pain. Follow up ranged from 24 to 36(average 30) months. Preoperative assessment included clinical examination, Lysholm, IKDC score and Radiological examination (X-ray, CT scan and MRI). 18 patients with history of dislocation and pain having bony malalignment and torn MPFL were treated with Fulkerson osteotomy and MPFL reconstruction and 4 patients with history of subluxation and pain having bony malalignment only were treated with Fulkerson osteotomy alone. Patients were followed up with the help of X-rays at regular interval and the clinical outcome was measured using scoring system.&lt;/p&gt;&lt;p&gt;&lt;strong&gt; &lt;/strong&gt;&lt;strong&gt;Results&lt;/strong&gt;-There was a significant improvement in postoperative assessment with regards to scoring system (Lysholm and IKDC) and knee pain. Union at osteotomy site for all patients was seen. None of the patients had further episode of dislocation or subluxation. Pain at femoral site of MPFL reconstruction in 2 cases persisted for 3 months followed by resolution of their symptoms. One of our patients had profuse swelling at the site of operation postoperatively which was treated with Rest, Ice Pack, Compression and Limb elevation. Out of 22 patients undertaken infection at osteotomy site was seen in 1 patient for which implant removal was done from osteotomy site after union.&lt;/p&gt;&lt;p&gt; &lt;strong&gt;Conclusion&lt;/strong&gt;-Anteromedial Tibial tuberosity osteotomy and MPFL reconstruction is a successful procedure to treat patellofemoral pain and instability.&lt;/p&gt;

Proximal realignmentとdistal realignmentの併用により良好な術後成績を得られた爪膝蓋骨症候群の1例

Proximal realignmentとdistal realignmentの併用により良好な術後成績を得られた爪膝蓋骨症候群の1例

ISOLATED MPFL RECONSTRUCTION VS. TIBIAL TUBERCLE OSTEOTOMY AND MEDIAL RETINACULAR PLICATION FOR RECURRENT PATELLAR INSTABILITY: A MATCHED, COHORT ANALYSIS OF CLINICAL OUTCOMES COMPARING TWO TECHNIQUES

Background:Historically, the most commonly utilized technique to address recurrent patellofemoral instability (PFI) was a combined proximal and distal realignment, specifically the tibial tubercle osteotomy (TTO) with a proximal medial retinacular plication/reefing/tightening/repair (MRP). Rising interest in the medial patellofemoral ligament reconstruction (MPFLR) over the last decade, now frequently performed as a more powerful isolated proximal realignment procedure, has prompted debate over the optimal technique to treat this common condition.Hypothesis/Purpose:The study hypothesis was that no difference would be detected in recurrent PFI rates or revision surgery rates between patients who underwent TTO-MRP vs. MPFLR.Methods:With cohorts derived from a large, single-center PFI database of 523 patients who underwent a variety of stabilization procedures, 114 eligible MPFLR patients were matched to 109 TTO patients based on age, gender, BMI, and TT-TG distance. Propensity score matching was conducted using logistic regression models to produce 1:1 matching, and a caliper of 0.2 standard deviations of the estimated propensity score was used to for the nearest neighbor matching algorithm. Final matching procedure resulted in 84 MPFLR patients and 84 TTO patients. These were compared on demographics and post-operative clinical results.Results:Demographic and radiologic comparisons of the cohorts are shown in Table 1, with the only difference between groups being an expected higher rate of patients with open physes in the MPFLR cohort. Table 2 shows the TTO-MRP group had longer follow up times, but comparable rates of return to sports. The MPFLR group had a higher rate of recurrent instability, but not to a significant degree, and a significantly higher incidence of revision patellar stabilization surgery (p<0.001). The TTO group had a higher rate of additional knee surgery, the majority of which were implant removal for TTO screws.Conclusion:The TTO-MRP shows equivalent or superior results to the MPFLR for treatment of PFI. However, implant removal may be common with TTO, though this may be somewhat technique-dependent. In the current landscape of increasing interest and utilization of MPFLR as an all-encompassing PFI surgery, the influence of distal bony realignment to minimize recurrence should not be underappreciated.Tables/Figures:

Anteriorization of the Tibial Tubercle With Osteotomy, Combined With Cartilage Restoration in the Patellofemoral Joint: A Surgical Technique

Left untreated, cartilage defects of the knee are responsible for substantial patient morbidity and may lead to osteoarthritis. This has led to the development of several techniques to improve healing potential, including microfracture, osteochondral autograft, osteochondral allografts, autologous chondrocyte implantation, and matrix-assisted autologous chondrocyte implantation. Of paramount importance when addressing patellofemoral (PF) cartilage defects is treating associated PF malalignment. We describe a surgical technique for tibial tubercle anteriorization in conjunction with autologous chondrocyte implantation for the treatment of PF cartilage lesions. In our opinion, a distal realignment procedure should be routinely performed for any cartilage restoration procedure of the PF joint as it may delay the onset of osteoarthritis.

New standardization method of tibial tubercle-posterior cruciate ligament distance according to patient size in patients with patellofemoral instability

BackgroundLarge differences in tibial tubercle–posterior cruciate ligament (TT-PCL) distance were described in several reports between countries, suggesting that abnormal TT-PCL distance is variable due to individual patient size. This study aimed to clarify the relationship between TT-PCL distance and patient size, and to determine a method for describing individualized TT lateralization. MethodsWe analyzed 41 patients with recurrent patellar dislocation (RPD) and 41 age-matched patients without patellar instability who underwent primary anterior cruciate ligament reconstruction (control). TT-PCL distance and tibia width (TW) were measured based on preoperative T2-weighted magnetic resonance imaging. Then, TT-PCL distance was standardized based on TW (TT-PCL ratio), and TT-PCL distance and ratio were compared between groups. Correlations were investigated among TT-PCL distance, TT-PCL ratio and each measurement (patient height, weight, TW). ResultsStrong positive correlations were observed between TW and patient height, and weak or moderate positive correlations were found between TT-PCL distance and each parameter. The mean TT-PCL distance was 21.2 and 20.6 mm (P = .39), while the mean TT-PCL ratio was 31.6% and 29.0% (P = .0093) in the RPD and control groups, respectively. The TT-PCL ratio was <34% in 39 of 41 knees (95.1%) in the control group. No correlation was indicated between the TT-PCL ratio and patient size. ConclusionsOur findings demonstrate that the TT-PCL ratio is not affected by patient size, although the TT-PCL distance is associated with knee size and patient height. The TT-PCL ratio could be an important index for identifying patients for whom distal realignment surgery should be considered.

Isolated reconstruction of medial patellofemoral ligament with an elastic femoral fixation leads to excellent clinical results.

The primary objective was to compare the functional outcomes after an isolated MPFL reconstruction using either a quasi-anatomical technique (group A) or an anatomical MPFL reconstruction (group B). The secondary objectives were to compare the rates of redislocation, range-of-motion and subjective patellar instability (Smillie test). A multicenter longitudinal prospective comparative study was performed. Group A had 29 patients and 28 were included in Group B. Patients with trochlear dysplasia types C and D and patients who had undergone a trochleoplasty, a distal realignment or patella distalization concurrently with MPFL reconstruction were excluded. The main evaluation criterion was the Kujala functional score. The mean postoperative Kujala was 90.4 (89.4 in group A and 92.1 in group B). Upon comparing the mean difference between pre- and post-operative values, no differences were detected between the two groups (n.s). Isolated quasi-anatomical MPFL reconstruction using a gracilis tendon autograft for recurrent patellar dislocation provides outcomes as good as the isolated anatomical MPFL reconstruction in patients with no trochlear dysplasia up to those with trochlear dysplasia type A and B at the 2-5years follow-up. Level IV.

Recurrent Patellofemoral Instability in the Pediatric Patient: Management and Pitfalls

The purpose of the review is to discuss the relevant pathoanatomy, management, complications, and technical considerations for recurrent patellofemoral instability (PFI) in the pediatric population. Special consideration is given to recent literature and management of the patient with repeat instability following surgery. Patellar stabilization surgery is in principle dependent upon restoration of normal patellofemoral anatomy and dynamic alignment. Historically, treatment options have been numerous and include extensor mechanism realignment, trochleoplasty, and more recently repair and/or reconstruction of the medial patellofemoral ligament (MPFL) as a dynamic check rein during initial knee flexion. In skeletally immature patients, preference is given to physeal-sparing soft tissue procedures. While medial patellofemoral ligament reconstruction has become a popular option, postoperative failure is a persistent issue with rates ranging from 5 to 30% for PFI surgery in general without any single procedure (e.g., distal realignment, MPFL reconstruction) demonstrating clear superiority. Failure of surgical patellar stabilization is broadly believed to occur for three main reasons: (1) technical failure of the primary stabilization method, (2) unaddressed static and dynamic pathoanatomy during the primary stabilization, and (3) intrinsic risk factors (e.g., collagen disorders, ligamentous laxity). PFI is a common orthopedic condition affecting the pediatric and adolescent population. Treatment of repeat instability following surgery in the PFI patient requires understanding and addressing underlying pathoanatomic risk factors as well as risks and reasons for failure.

Arthroscopic Lateral Retinacular Release and Modified Goldthwait Technique for Patellar Instability

Surgical options for patellofemoral (PF) disorders include proximal or distal realignment, cartilage restoration techniques, open or arthroscopic lateral retinacular release, and medial soft-tissue reefing. Skeletal immaturity and donor-site morbidity can be of concern in most reconstructive procedures. The Goldthwait procedure with hemi-patellar transfer and medialization combined with arthroscopic lateral retinacular release results in medialization of the PF contact point in flexion and corrects maltracking to prevent recurrent patellar dislocation. This functional procedure is indicated for PF instability and has historically been used in children to accommodate the immaturity of the tibial tubercle and physis. The purpose of surgical correction is to improve PF tracking, reducing the lateralizing forces on the patella with the correction of the Q angle (angle between the quadriceps tendon and patellar tendon). The purpose of this Technical Note was to describe, in detail, arthroscopic lateral retinacular release combined with the modified Goldthwait procedure for recurrent patellar instability.

Medial Patellofemoral Ligament Reconstruction and Nonanatomic Stabilization Techniques in Skeletally Immature Patients.

Patellar instability is a common cause of knee disability in children and adolescent, with a high recurrence rate. When conservative treatment fails, surgical options should be considered. The femoral insertion of the medial patellofemoral ligament (MPFL) is in close proximity to the distal femoral growth plate and precautions should be taken to avoid injuries to the physis. Anatomical features of the MPFL complex, with focus on the relationship between femoral MPFL attachment and femoral physis, are discussed together with surgical tips to avoid injuries to the growth plates. The aim of this article is to review the recent literature regarding MPFL reconstruction and other stabilization techniques for patellofemoral instability in skeletally immature patients, focusing on the different surgical options available. These can be classified as anatomical versus nonanatomical, proximal versus distal realignments, or based on the graft used: free graft and pedicled graft (quadriceps, patellar tendon, hamstring, and adductor magnus).

Distal alignment procedures for patellofemoral instability: comprehensive review of the literature.

Patellofemoral disorders are a common cause of complaint in adolescent patients. Several distal realignment procedures performed in isolation or combination with proximal alignment have been described. To clarify the role of distal alignment for patellofemoral instability, a systematic review of the literature was conducted. Two independent reviewers accessed the following databases: PubMed, Medline, CINAHL, Cochrane, EMBASE and Google Scholar. A total of 1478 patients with a mean age of 22.78years were included. The mean follow-up was 86.53 months. The average Kujala score improved from 57.66 to 82.73. The average Lysholm score improved from 63.25 to 87.87, and the average Tegner score from 3 to 4.16. VAS score improved from an average 8 to 2.56. We account a total of 46 major complications, 45 minor complications and 95 recurrences. The risk of a recurrence is 6.42%. A total of 122 additional surgeries were performed during the follow-up. This systematic review of literature suggests the importance to identify the pathological background that predisposes patients for developing patellofemoral instability and its implications for the decision-making process. The optimal treatment for patellofemoral instability should be individualized to address the specific anatomical abnormalities that contribute to patellofemoral dislocations. Distal alignments are a feasible solution to restore correct patellar biomechanics and tracking, leading to an improvement of patients' quality of life.

The Outcomes of Isolated Distal Realignment Procedures in Patellofemoral Instability: A Systematic Review and Meta-analysis.

Distal realignment procedures are now commonly performed routinely with proximal realignment procedures. Despite so, only a limited number of publications exist that have looked into the efficacy of isolated distal realignment procedures, and whether there is indeed a need for routine proximal realignment procedures to be added to the distal realignment procedures. The current systematic review and meta-analysis aims to evaluate the outcomes of isolated distal realignment procedures in the management of patellofemoral instability. The review was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRSIMA) guidelines. All studies that reported the outcomes of isolated distal realignment procedures for patellofemoral instability were included. A total of six publications were included, with 347 knees. All studies consistently reported a decrease in the rates of patellofemoral instability or maltracking (odds ratio [OR]: < 0.01; 95% confidence interval [CI]: < 0.01-0.01) and an increase in the odds of having a good outcome (OR: 0.01; 95% CI: < 0.01-0.02) after distal realignment procedures. A total of 24 out of 306 patients (7.8%) had postoperative instability or maltracking, and a total of 220 out of 303 patients (72.6%) were rated to have good or excellent outcomes postoperatively. Isolated distal realignment procedures can lead to good outcomes when used in the management of patellofemoral instability. These include a significantly decreased rate of patellofemoral instability or maltracking and a significantly increased number of patients with excellent or good outcomes postoperatively. Comparisons between patients with and without additional proximal realignment procedures suggest that additional proximal realignment procedures do not definitely improve the outcomes of distal realignment procedures and, therefore, should not be routinely performed in all patients undergoing distal realignment procedures. The Level of Evidence for this study is IV.