Patella alta

Prior literature suggests that patellofemoral instability (PFI) is significantly more prevalent in women than in men. This higher prevalence is commonly attributed to anatomical differences between sexes, particularly with patellofemoral alignment. These differences encompass a higher rate of trochlear dysplasia (TD), patella alta, an increased Q angle, and soft tissue imbalances. In recent years worse outcomes have been reported in female patients after patellofemoral stabilization surgery using medial patellofemoral ligament reconstruction (MPFLr) alone or in combination with a tibial tubercle osteotomy (TTO), for this reason an "à la carte" plan (addressing the individuals anatomical risk factors) could be more appropriate for female patients...

PURPOSE: This study aims to report the epidemiology of patellar sleeve injuries, describe diagnostic findings and treatment, and assess functional outcomes following different treatments. METHODS: A medical database was queried from 1990 to 2016 to identify patients ≤18 years presenting to a single pediatric institution with a patellar sleeve injury. Patients with significant comorbidities or previously operatively treated for ipsilateral knee injuries were excluded...

BACKGROUND: Research on the cause of lateral patellar dislocation (LPD) has focused on trochlear morphologic parameters, joint alignment, and patellofemoral soft tissue forces. A paucity of information is available regarding how patellar morphologic parameters influence the risk for LPD. PURPOSE/HYPOTHESIS: The purpose was to assess whether patellar morphology is a risk factor for recurrent LPD. It was hypothesized that (1) patients with recurrent LPD would have decreased patellar width and volume and (2) patellar morphologic parameters would accurately discriminate patients with recurrent LPD from controls...

This case report details the clinical evaluation, imaging findings, and surgical management of a 17-year-old female with a two-year history of persistent knee pain and recurrent patellar dislocations. Despite the absence of traumatic injury, the patient exhibited significant anatomical abnormalities, including a laterally dislocated patella, shallow trochlear groove, increased tibial tuberosity to trochlear groove (TT-TG) distance, and patella alta by calculating Insall-Salvati ratio. The Insall-Salvati ratio is a radiographic measurement used to assess the position of the patella within the knee joint...

BACKGROUND: Tibial tubercle osteotomy (TTO) is a well-established surgical treatment option for patellofemoral instability and pain. TTO with distalization (TTO-D) is indicated for patients with patellofemoral instability, patellar malalignment, and patella alta. The current literature demonstrates several complications that may be associated with TTO, with reportedly higher rates of complications associated with TTO-D. PURPOSE: To analyze and compare complication rates after TTO without distalization (TTO-ND) and TTO-D and assess risk factors associated with complications...

BACKGROUND: Recent studies have reported conflicting results as to whether isolated medial patellofemoral ligament reconstruction (MPFLr) leads to decreased patellar height. PURPOSE: To investigate if patellar stabilization surgery not intended to address patella alta influences patellar height. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A multicenter retrospective chart review was conducted, and patients who underwent MPFLr, medializing tibial tuberosity osteotomy (TTO), and/or trochleoplasty between 2016 and 2020 were included...

BACKGROUND: There are several imaging-based measurements for patellofemoral height, which are obtained from sagittal images. However, these methods can be misleading with sagittal oblique slices and when the patella is tilted and/or chronically subluxated. This study aimed to describe a simple method of measuring patellar height using axial patellotrochlear overlap (APTO) on MRI. METHODS: A retrospective observational study of 97 knees from 251 patients, excluding those with fractures, massive effusion, or patellofemoral conditions...

Patella alta is a known risk factor for patellar instability,contributes to increased length changes of the medial patellofemoral complex (MPFC), and is associated with high rates of failure of MPFC reconstruction. Distalization through tibial tuberosity osteotomy (TTO) is a surgical option to address patella alta during patellar stabilization surgery. However, distalization has been shown to have greater complications than other types of TTO, and precise indications through proper assessments of patellar height are needed...

Patellofemoral instability (PFI) describes a (sub)luxation of the patella in the patellofemoral joint. Pathophysiologically, PFI is usually due to a nonphysiological movement of the patella, so-called maltracking, either due to acute trauma with injury to the supporting ligamentous apparatus or due to the presence of anatomical risk factors. Radiologically assessable risk factors for maltracking include trochlear dysplasia, patella alta, patellar tilt, lateralization of the tibial tuberosity, torsional deformity and genu valgum...

Patellofemoral instability is a complex pathology with multiple risk factors, which affects mostly young females and may avert them from both activities of daily living and sports participation. Risk factors for instability include patella alta, trochlea dysplasia, abnormal lateral patellar tilt, and increased tibial tuberosity-trochlea groove distance. The knowledge of these anatomical abnormalities is the key to identifying the problem and succeeding in treating the patients.

BACKGROUND: "Coronal split/overlap repair" patellar tendon shortening (PTS) is a technique that is utilized to treat patella alta and can be combined with distal femoral extension osteotomy (DFEO) for the treatment of crouch gait in skeletally immature patients with cerebral palsy. DESCRIPTION: The patellar tendon is split in the coronal plane. The ventral patellar tendon flap is released from its patellar attachment and is reflected distally over its tibial attachment, exposing a dorsal flap...

BACKGROUND: Distalization tibial tubercle osteotomy (TTO) is an effective treatment for improving patellar height in patients with patella alta associated with patellofemoral instability and cartilage lesions. The addition of a patellar tendon tenodesis has been suggested; nonetheless, concerns exist regarding possible increased patellofemoral cartilage stresses. PURPOSE: To evaluate pre- and postoperative patellar tendon length and alignment parameters on magnetic resonance imaging (MRI), as well as patient-reported outcome measures (PROMs) after distalization TTO without patellar tendon tenodesis...

OBJECTIVES: Patellofemoral instability (PFI) has multiple predisposing anatomic factors including ligamentous hyperlaxity, coronal and axial malalignment, patella alta, trochlea dysplasia, excessive lateral patellar tilt, and excessive lateral Q vector. Yet, few studies have analyzed surgical thresholds for performing axial alignment corrective osteotomies in the treatment of PFI and patella maltracking. The objective of this systematic literature review was to determine if there is a threshold for axial plane alignment that triggers surgical correction for treatment of patellar instability in the published literature...

PURPOSE: To evaluate differences in knee kinematic outcomes of patellar-lowering surgery, specifically patellar tendon advancement or patellar tendon shortening, compared with no-patellar-lowering surgery in multilevel surgery for children with cerebral palsy and crouch gait. METHODS: Four databases were searched to retrieve studies published from inception until 2023. Three reviewers independently screened for studies with observational or randomized control designs, comparing two groups of patients with cerebral palsy and crouch gait who underwent multilevel surgery (with patellar-lowering surgery versus no-patellar-lowering surgery), where various gait analysis outcomes were reported (CRD42023450692)...

Patella alta (PA) and patella baja (PB) affect 1-2% of the world population, but are often underreported, leading to potential complications like osteoarthritis. The Insall-Salvati ratio (ISR) is commonly used to diagnose patellar height abnormalities. Artificial intelligence (AI) keypoint models show promising accuracy in measuring and detecting these abnormalities.An AI keypoint model is developed and validated to study the Insall-Salvati ratio on a random population sample of lateral knee radiographs. A keypoint model was trained and internally validated with 689 lateral knee radiographs from five sites in a multi-hospital urban healthcare system after IRB approval...

PURPOSE: To investigate if Patellotrochlear index (PTI) predicts patella alta as determined by tibial based methods of Insall Salvati (IS) and Caton Deschamp (CD) in a pathological population (with patellofemoral pain and/or instability). In addition to determining if PTI and Sagittal Patellofemoral engagement (SPE) correlate with trochlea length as determined by Lateral condyle index (LCI). METHODS: Patients with confirmed patella alta (IS/CD ratio > 1.2) undergoing tibial tubercle osteotomy for patellofemoral pain/instability with an available MRI were included...

PURPOSE: To investigate the relationship between the supratrochlear rim and isolated patellar chondromalacia (PC) using magnetic resonance imaging (MRI) scans of the knee. METHODS: Patients without patellofemoral pain (control group) and patients with patellofemoral pain and diagnosed with stage III or IV PC based on MRI (defect group) were retrospectively identified. Patients with a history of patellar subluxation were excluded. We used patient MRI scans to perform 20 anatomical measurements of the patellofemoral joint...

BACKGROUND: The intercondylar notch (ICN) and the anterior cruciate ligament (ACL) are important structures in knee morphometry, with key roles in stabilizing the knee. AIM: To determine the associations between the specific shape of the ICN (A-, W-, or U-shape) and the ACL size in patients with intact ACLs. METHODS: Magnetic resonance imaging (MRI) scans were independently analyzed by two experts: one orthopedic surgeon and one imaging physician...

Lateral patellar dislocations are the second most common type of traumatic knee injury, accounting for approximately 2-3% of cases, the most common being anterior cruciate ligament (ACL) injury. There are several well-documented anatomical risk factors predisposing to patellofemoral instability for example: patella alta, trochlear dysplasia, ligamentous laxity, and genu valgum. Co-existing medial collateral ligament injury in cases of patellar dislocations in the absence of ACL injury is uncommon and infrequently reported in the literature...

When planning an adolescent's primary surgery for recurrent patella instability, the surgeon must weigh the failure risk of performing medial patellofemoral reconstruction (MPFLR) versus the potential morbidity of adding a concomitant bony procedure, such as tibial tubercle osteotomy (TTO). In this age group, isolated MPFLR is an excellent operation with high clinical success, low failure rates, and favorable complication profile. Patients with high grade J-sign and severe trochlea dysplasia, apprehension into deep flexion, and extremes of bony malalignment, including elevated tibial tubercle-trochlear groove distance may benefit from "doing more" than MPFLR alone...