Knee lateral retinaculum

OBJECTIVE: The purpose of this study was to assess the frequency and MRI features of a subcutaneous anterior knee mass herniated from the infrapatellar fat pad (IPFP) through a focal defect of the patellar retinaculum (PR). MATERIALS AND METHODS: This study included 94 patients (44 men; age range, 1-80 years; mean age, 52 years) with clinically palpable subcutaneous anterior knee masses who underwent MRI between January 2007 and July 2022. Two radiologists retrospectively reviewed MRI findings of subcutaneous masses associated with a focal PR defect (location and size of the defect and characteristics of the mass)...

A 3-year-old boy was found to have a painless mass over his right anterior lateral knee for the previous 6 months. The mass was hardly identified during knee extension and became visible upon squatting. There was no specific finding on ultrasound imaging over his right knee at the supine extended position. During squatting, ultrasound imaging showed an ill-demarcated hyperechoic mass protruding next to the cartilage overlying the distal femur towards the subcutaneous layer through a slit over the lateral patellar retinaculum...

Obligatory patella dislocation in flexion is an uncommon form of patellar instability, where the patella is located in extension and dislocates with every episode of knee flexion. This results in dramatically altered patellofemoral kinematics and can be extremely debilitating due to extensor strength deficits and lack of knee confidence in flexion. Concomitant pathology, which is often seen, includes a tight lateral retinaculum and a shortened extensor mechanism. Lengthening the extensor mechanism is a critical part of successful patellar stabilization, and has not been well-reported...

OBJECTIVE: Minimal invasive approach has been increasingly used in total knee arthroplasty (TKA) and more is expected of early rehabilitation in terms of pain release and recovery of knee function. The approach type is one of the major factors that determines the early rehabilitation after TKA. The purpose of this study is to determine whether mini-subvastus approach (MSVA) is superior to the traditional medial parapatellar approach (MPA) in TKA. METHODS: From 2018 to 2019, a randomized double-blinded prospective study was conducted on 58 patients who underwent simultaneous bilateral TKA...

OBJECTIVE: The exact mechanism of patellofemoral instability has not been clearly clarified. The current study aims to explore the correlation between the tibial tuberosity-trochlear groove (TT-TG) distance and other patellar stability parameters. METHODS: A total of 60 individuals aged 18 to 40 years who underwent knee computed tomography (CT) examination between September 2014 and December 2017 were retrospectively recruited. Five reference sites were selected on the femoral trochlear articular surface in every CT image...

Medial dislocation of patella has been commonly reported as a complication of the surgical release of the lateral patella-femoral ligament. A traumatic medial eversion-dislocation of the patella has not been earlier reported. We report an unusual case of traumatic medial patellar eversion-dislocation in a young adult patient whose magnetic resonance imaging (MRI) showed a discontinuity in medial and lateral patellar retinacula. However, intraoperatively, the retinacula were found intact, and relocation of the patella was achieved by flipping the patella through a small hole in the patellar tendon...

Severe flexion-impeding knee stiffness is a common clinical condition that challenges orthopaedic surgeons. A mini-invasive and effective release technique to address this special condition is still being pursued. We describe a mini-invasive quadriceps-plasty that is performed through a small incision on the supralateral side of the knee and includes release of the retinaculum and patellofemoral joint, re-creation of the suprapatellar pouch and medial and lateral gutters, overlapping Z-plasty of the rectus femoris and vastus intermedius, and transfer of the vastus lateralis...

INTRODUCTION: Traditional techniques can enlarge the medial tibiofemoral joint space width (JSW) for meniscal repairs, but a remnant ligament laxity may be developed. Alternatively, the debridement of the inner retinaculum layer may result in a balanced JSW without causing extra-ligament damage (retinaculum layers II and collateral ligament). PURPOSE: The purpose of this study was to determine whether a concentric arthroscopic debridement of the inner retinaculum layer increases the tibiofemoral JSW in patients with meniscal injuries...

Trochlear dysplasia consists in deficient trochlear concavity, giving rise to a flat or convex trochlea, and is the main risk factor for patellar dislocation. Surgical indications depend on familiarity with trochlear dysplasias, and especially those of high grade, identified on clinical examination and standard and cross-sectional imaging, and on quantification of associated instability factors. Treatment strategy is accordingly determined "à la carte" to correct these factors one by one. Sulcus deepening trochleoplasty corrects the morphology and is the appropriate etiological treatment...

The lateral patellofemoral complex is an important stabilizer to medial and lateral displacement of the patella. Soft tissue abnormalities can range from pathologic tightness to laxity, presenting with symptoms related to patellar instability, anterior knee pain, or arthritis. Clinical evaluation should be performed to confirm patellar dislocation, assess the integrity of the lateral and medial soft tissues, and explore other pathoanatomic factors that may need to be addressed. Lateral retinacular lengthening is recommended over lateral release owing to the potential of iatrogenic medial instability with release, and a lateral patellofemoral ligament reconstruction can be performed to effectively treat medial instability...

Mucoid degeneration of the anterior cruciate ligament (ACL) is a rare cause of anterior knee pain (AKP). Some case reports have been published; however, it is difficult to diagnose and is often underdiagnosed or misdiagnosed because of its pathophysiological ambiguity. We report a rare case of a patient diagnosed with bilateral mucoid degeneration of the ACL with AKP and no limited joint range of motion (ROM). A 59-year-old man with spontaneous right AKP was admitted to our hospital. He first underwent arthroscopic resection of the thickened medial plica protruding far into the medial patellofemoral joint (PFJ) but felt little effectiveness thereafter...

INTRODUCTION: Dislocation of patella is a very common injury which usually reduces spontaneously or can be reduced easily using gentle manipulation. Irreducible patellar dislocations are rare and usually result due to either rotation of patella along the horizontal or vertical axis or due to bony impaction. Neglected locked patellar dislocations are extremely rare injuries presenting additional challenges. CASE REPORT: We are reporting a case of a 24-year female who presented to us 4 months after suffering a knee injury for which she received native treatment initially...

Purpose: Recurrent patellar dislocation (RPD) is the most common complication of patellar instability and the medial patellofemoral ligament (MPFL) reconstruction has become its reference treatment. Lateral patellar retinaculum (LPR) release used to be performed in association with MPFL reconstruction. The aim of this study was to investigate the added values of MPFL reconstruction plus LPR release for RPD. Methods: After Institutional Review Board approval, RPD patients from October 2014 to April 2019 were randomly assigned into two groups (isolated MPFL reconstruction [Group I] and MPFL reconstruction plus LPR release [Group II]) and prospectively assessed until 12 months after surgery...

PURPOSE: Focal, patellar cartilage defects are a challenging problem as most cases have an underlying multifactorial pathogenesis. This systematic review of current literature analysed clinical results after regenerative cartilage repair of the patella with a special focus on the assessment and treatment of existing patellofemoral malalignment. METHODS: A systematic review was conducted to identify articles reporting clinical results after cartilage regenerative surgeries of the patella using the PubMed and Scopus database...

Objective: To compare the clinical effects of arthroscopic lateral retinacular proximal release and "L" type release for lateral patellar compression syndrome. Methods: Sixty four lateral patellar compression syndrome (LPCS) patients were recruited who had arthroscopic surgery during September 2004 to January 2019 at Department of Sports Medicine,Peking University Third Hospital by the same group of doctors and a retrospective comparative study was conducted accordingly. Among them,24 cases underwent the traditional proximal release of lateral patellar retinaculum (traditional group),including 7 males and 17 females with an age of (42...

Introduction: patellar instability is a rare multifactorial condition whose treatment is complex. The purpose of this study was to describe cases of patellar instabilities and then to assess treatment outcomes in low-income countries. Methods: the study was conducted from March 2013 to February 2018. Eight patients aged >15 years and who had undergone surgery for objective patellar instability were enrolled. Before and after surgery knee function was assessed using IKDC score...

The lateral retinaculum is a 2-layered structure. The plane between the superficial oblique fibers and the deep transverse fibers allows for coronal plane Z-lengthening of the lateral retinaculum. The lengthening procedure can be used for treatment of lateral patellar hypercompression syndrome or as an adjunct to surgical procedures undertaken to address patellar instability. This article describes the surgical technique for lateral retinacular lengthening. Level 1: Knee. Level 2: Malalignment, patellofemoral, other...

INTRODUCTION: Congenital dislocation of the patella (CDP) is a rare condition and its treatment is not well defined. In CDP, patella is dislocated on the lateral aspect of the distal femur, laterally from the trochlear groove, it cannot be reduced manually and it is almost always associated with genu valgum, lateral torsion of the proximal tibia, and flexion contracture of the knee. This condition is present at birth, but the clinical findings can be subtle at birth due to the size and character of the structures being examined; early diagnosis is essential, but it may be delayed to late childhood or adulthood...

PURPOSE: There are certain risk factors responsible for patella instability that should be identified before choosing the most appropriate treatment. METHODS: We evaluated 83 skeletally immature patients who, after two or more patellar dislocation episodes, underwent surgical treatment to address the condition of patellar instability. Each patient was evaluated for patellar instability risk factors using the Balcarek patellar instability severity score. Evaluation of patellar instability included knee MRI to systematically identify anatomical risk factors...

INTRODUCTION: Lateral patellar compression syndrome is one of the causes of anterior knee pain in young adults and resulted from tight lateral patellar retinaculum. The aim of our study is to compare between open and arthroscopic release of lateral patellar compression syndrome in relation of functional outcome, time of surgical procedure, length of hospital stays, intraoperative and postoperative complications as bleeding, infection, recurrence, and patellar instability with 2 years of follow-up...