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Knee Surgery, Sports Traumatology,... Oct 2014The patellofemoral pain syndrome (PFPS) is a possible cause for anterior knee pain, which predominantly affects young female patients without any structural changes such... (Review)
Review
UNLABELLED
The patellofemoral pain syndrome (PFPS) is a possible cause for anterior knee pain, which predominantly affects young female patients without any structural changes such as increased Q-angle or significant chondral damage. This literature review has shown that PFPS development is probably multifactorial with various functional disorders of the lower extremity. Biomechanical studies described patellar maltracking and dynamic valgus in PFPS patients (functional malalignment). Causes for the dynamic valgus may be decreased strength of the hip abductors or abnormal rear-foot eversion with pes pronatus valgus. PFPS is further associated with vastus medialis/vastus lateralis dysbalance, hamstring tightness or iliotibial tract tightness. The literature provides evidence for a multimodal non-operative therapy concept with short-term use of NSAIDs, short-term use of a medially directed tape and exercise programmes with the inclusion of the lower extremity, and hip and trunk muscles. There is also evidence for the use of patellar braces and foot orthosis. A randomized controlled trial has shown that arthroscopy is not the treatment of choice for treatment of PFPS without any structural changes. Patients with anterior knee pain have to be examined carefully with regard to functional causes for a PFPS. The treatment of PFPS patients is non-operative and should address the functional causes.
LEVEL OF EVIDENCE
V.
Topics: Hip; Humans; Knee Joint; Patella; Patellofemoral Pain Syndrome; Physical Therapy Modalities; Quadriceps Muscle
PubMed: 24221245
DOI: 10.1007/s00167-013-2759-6 -
Stem Cell Research & Therapy Jul 2021Chondromalacia patellae (CMP), also known as runner's knee, typically occurs in young patients, which is characterized by anterior knee pain (AKP) that is associated... (Review)
Review
Chondromalacia patellae (CMP), also known as runner's knee, typically occurs in young patients, which is characterized by anterior knee pain (AKP) that is associated with visible changes in patellar cartilage. The initial pathological changes include cartilage softening, swelling, and edema. CMP is caused by several factors, including trauma, increased cartilage vulnerability, patellofemoral instability, bony anatomic variations, abnormal patellar kinematics, and occupation hazards. CMP may be reversible or may progress to develop patellofemoral osteoarthritis. Quadriceps wasting, patellofemoral crepitus, and effusion are obvious clinical indications. Additionally, radiological examinations are also necessary for diagnosis. Magnetic resonance imaging (MRI) is a non-invasive diagnostic method, which holds a promise in having the unique ability to potentially identify cartilage lesions. Modalities are conventionally proposed to treat cartilage lesions in the PF joint, but none have emerged as a gold standard, neither to alleviated symptoms and function nor to prevent OA degeneration. Recently, researchers have been focused on cartilage-targeted therapy. Various efforts including cell therapy and tissue emerge for cartilage regeneration exhibit as the promising regime, especially in the application of mesenchymal stem cells (MSCs). Intra-articular injections of variously sourced MSC are found safe and beneficial for treating CMP with improved clinical parameters, less invasiveness, symptomatic relief, and reduced inflammation. The mechanism of MSC injection remains further clinical investigation and is tremendously promising for CMP treatment. In this short review, etiology, MRI diagnosis, and treatment in CMP, especially the treatment of the cell-based therapies, are reviewed.
Topics: Cartilage, Articular; Cell- and Tissue-Based Therapy; Chondromalacia Patellae; Humans; Knee Joint; Magnetic Resonance Imaging; Osteoarthritis, Knee; Patella
PubMed: 34275494
DOI: 10.1186/s13287-021-02478-4 -
Swiss Medical Weekly Jan 2020The role of the patella is paramount in the transmission of the quadriceps muscle forces, the increase of the lever arm, the distribution of the forces on the trochlea... (Review)
Review
The role of the patella is paramount in the transmission of the quadriceps muscle forces, the increase of the lever arm, the distribution of the forces on the trochlea and the centring of the extensor apparatus. Despite the low incidence of patellar factures in comparison with other lower limb fractures, the painful and functional complications, such as knee stiffness, loss of extension and patellofemoral osteoarthritis, can be very disabling and will often compromise the return to a professional or recreational activity and induce falls in the elderly population. Treatment can be conservative or surgical, provided that it is adapted to the type of fracture. Undisplaced fractures with an intact extensor mechanism can be treated nonoperatively. Surgical treatment is recommended for fractures that either disrupt the extensor mechanism or have more than 2 to 3 mm of step-off and more than 1 to 4 mm of displacement. Tension band fixation is the most commonly employed surgical technique. In most cases, hardware has to be removed after fracture healing because of implant-related pain. Operative treatment of comminuted patellar fractures presents a significant challenge to surgeons. Failure to restore the articular surface contour results in posttraumatic arthritis. Anatomical reconstruction of the articular surface is the only way to prevent the development of posttraumatic osteoarthritis. Typically, fracture classification and thus treatment choice are based on anteroposterior and lateral radiographs of the knee, but when computed tomography of the knee was performed pre-operatively, both the classification and treatment were modified thanks to a better understanding of the fracture complexity. The purpose of this article is to review current treatment strategies and optimise the management of adult patients with patellar fractures.
Topics: Fractures, Bone; Humans; Knee Injuries; Orthopedic Procedures; Patella
PubMed: 31940427
DOI: 10.4414/smw.2020.20165 -
Orthopaedics & Traumatology, Surgery &... Feb 2019Patellar complications are a source of poor total knee arthroplasty (TKA) outcomes that can require re-operation or prosthetic revision. Complications can occur with or... (Review)
Review
Patellar complications are a source of poor total knee arthroplasty (TKA) outcomes that can require re-operation or prosthetic revision. Complications can occur with or without patellar resurfacing. The objective of this work is to answer six questions. (1) Have risk factors been identified, and can they help to prevent patellar complications? Patellar complications are associated with valgus, obesity, lateral retinacular release, and a thin patella. Selecting a prosthetic trochlea that will ensure proper patellar tracking is important. Resurfacing is an option if patellar thickness is greater than 12mm. (2) What is the best management of patellar fracture? The answer depends on two factors: (a) is the extensor apparatus disrupted? and (b) is the patellar implant loose? When either factor is present, revision surgery is needed (extensor apparatus reconstruction, prosthetic implant removal). When neither factor is present, non-operative treatment is the rule. (3) What is the best management of patellar instability? Rotational malalignment should be sought. In the event of femoral and/or tibial rotational malalignment, revision surgery should be considered. If not performed, options consist of medial patello-femoral ligament reconstruction and/or medialization tibial tuberosity osteotomy. (4) What is the best management of patellar clunk syndrome? When physiotherapy fails, arthroscopic resection can be considered. Recurrence can be treated by open resection, despite the higher risk of complications with this method. (5) What is the best management of anterior knee pain? The patient should be evaluated for causes amenable to treatment (fracture, instability, clunk, osteonecrosis, bony impingement on the prosthetic trochlea). If patellar resurfacing was performed, loosening should be considered. Otherwise, secondary resurfacing is appropriate only after convincingly ruling out other causes of pain. A painstaking evaluation is mandatory before repeat surgery for anterior knee pain: surgery is not in order in the 10% to 15% of cases that have no identifiable explanation. (6) What can be done to treat patellar defects? Available options include re-implantation (with bone grafting, cement, a biconvex implant, or a metallic frame), bone grafting without re-implantation, patellar reconstruction, patellectomy (best avoided due to the resulting loss of strength), osteotomy, and extensor apparatus allograft reconstruction. LEVEL OF EVIDENCE: V, expert opinion.
Topics: Arthralgia; Arthroplasty, Replacement, Knee; Bone Transplantation; Fractures, Bone; Humans; Knee Prosthesis; Orthopedic Procedures; Osteonecrosis; Patella; Patellar Dislocation; Prosthesis Failure; Risk Factors
PubMed: 29990602
DOI: 10.1016/j.otsr.2018.04.028 -
Journal of Orthopaedic Research :... Dec 2018The term jumpers knee for patella tendinitis, as coined by Dr. Martin Blazina, is now commonly referred to as tendinopathy. He believed it was associated with patella... (Review)
Review
The term jumpers knee for patella tendinitis, as coined by Dr. Martin Blazina, is now commonly referred to as tendinopathy. He believed it was associated with patella alta. Since then multiple studies have failed to reliably show an association between patella tendinopathy and associated intrinsic risk factors. There is, unfortunately, a well-established doctrine that the extensor mechanism is simply a pulley. The goal of the review is to examine the biomechanics of the extensor mechanism and apply this to studies investigating intrinsic risk factors for patella tendinopathy. A better understanding of the biomechanics of the extensor mechanism may stimulate the discovery of intrinsic risk factors for developing patella tendinopathy, and subsequent surgical options to address them. Clinical significance: The aim of this review is to direct future research into biomechanical risk factors for developing patella tendinopathy and subsequently, possible treatments. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:3105-3112, 2018.
Topics: Biomechanical Phenomena; Humans; Knee Joint; Patella; Risk Factors; Tendinopathy
PubMed: 30074265
DOI: 10.1002/jor.24120 -
Journal of the American Academy of... Jul 2022The lateral patellofemoral joint soft tissues contain key structures that surround and balance the joint. These structures can affect joint tracking, stability, and... (Review)
Review
The lateral patellofemoral joint soft tissues contain key structures that surround and balance the joint. These structures can affect joint tracking, stability, and force distribution. It is important to understand the lateral patellofemoral anatomy and biomechanics, and their relationship with patellofemoral instability, anterior knee pain, and osteoarthritis. Lateral-sided surgical procedures such as lateral release, lateral retinacular lengthening, and partial lateral patellar facetectomy can be useful in the treatment of such patellofemoral problems.
Topics: Arthroplasty, Replacement, Knee; Biomechanical Phenomena; Knee Joint; Patella; Patellofemoral Joint
PubMed: 35858252
DOI: 10.5435/JAAOSGlobal-D-21-00255 -
European Journal of Human Genetics :... May 2019We review genetic diseases with identified molecular bases that include abnormal, reduced (hypoplasia), or absent (aplasia) patellae as a significant aspect of the... (Review)
Review
We review genetic diseases with identified molecular bases that include abnormal, reduced (hypoplasia), or absent (aplasia) patellae as a significant aspect of the phenotype. The known causal genes can be broadly organized according to three major developmental and cellular processes, although some genes may act in more than one of these: limb specification and pattern formation; DNA replication and chromatin structure; bone development and differentiation. There are also several genes whose phenotypes in mice indicate relevance to patellar development, for which human equivalent syndromes have not been reported. Developmental studies in mouse and chick embryos, as well as patellar involvement in human diseases with decreased mobility, document the additional importance of local environmental factors in patellar ontogenesis. Patellar anomalies found in humans can be an important clue to a clinical genetic diagnosis, and a better knowledge of the genetics of patellar anomalies will improve our understanding of limb development.
Topics: Biological Evolution; Bone Diseases; Chromatin; DNA Replication; Genetic Phenomena; Humans; Patella
PubMed: 30664715
DOI: 10.1038/s41431-018-0329-6 -
World Journal of Surgical Oncology Apr 2015The patella is an uncommon location for cancerous occurrence and development. The majority of tumors of the patella are benign, with a significant incidence of giant... (Review)
Review
The patella is an uncommon location for cancerous occurrence and development. The majority of tumors of the patella are benign, with a significant incidence of giant cell tumors and chondroblastoma. With the development of modern diagnostic technologies, there appear however many other histological types which raise challenges of diagnosis and treatment. In this article, we review the reported histological types of primary patellar tumors. Specifically, epidemiology, symptomatology, imageology, histopathology, and treatment options for these histological lesions will be discussed, respectively. As there is an increasing focus on the diagnosis and the treatment of these lesions, the availability of the integrated information about primary patellar tumors becomes more significant.
Topics: Bone Neoplasms; Humans; Patella
PubMed: 25906772
DOI: 10.1186/s12957-015-0573-y -
BMJ Case Reports Mar 2022Acute patella dislocations account for approximately 2%-3% of knee injuries and are therefore a relatively common presentation in the accident and emergency department....
Acute patella dislocations account for approximately 2%-3% of knee injuries and are therefore a relatively common presentation in the accident and emergency department. The majority of patella dislocations can be reduced with simple manoeuvres or even spontaneously and can be managed conservatively by bracing and rehabilitation. The aim of this study is to identify and review the main causes of the unique and unexpected event of irreducible patella dislocation and their characteristic presentations. Irreducible patella dislocations can happen but are very rare. Currently, a limited number of case reports are available, prompting for a need for research on this topic. This case study can shed light on the possible pathogenesis and pathognomonic features of irreducible patella dislocations and provide insight on the available therapeutic approaches.
Topics: Humans; Joint Dislocations; Knee Injuries; Patella; Patellar Dislocation
PubMed: 35264391
DOI: 10.1136/bcr-2021-248398 -
Journal of Orthopaedic Research :... Mar 2023To determine the cross-sectional and longitudinal associations of patella alignment with cartilage relaxation and patients' self-reported symptoms. Thirty participants...
To determine the cross-sectional and longitudinal associations of patella alignment with cartilage relaxation and patients' self-reported symptoms. Thirty participants with isolated patellofemoral joint (PFJ) degeneration (six males, 53.7 ± 9.3 years) and 24 controls (12 males, 47.6 ± 10.7 years) were included. Magnetic resonance assessment was performed to provide grading of structural abnormalities, cartilage relaxation times, and patella alignment. Self-reported symptoms were assessed using the self-administrated knee injury and osteoarthritis outcome score (KOOS). All participants were examined at baseline and 3 years. Statistical parametric mapping and Pearson partial correlation were used to evaluate the associations between patella alignment with cartilage relaxation times and self-reported symptoms, respectively. The analyses were performed between baseline (cross-sectional) as well as the baseline against 3 years (longitudinal). Results indicated that patella height and patella flexion were associated with T and T relaxation times at baseline (percentages of voxels showing significant correlation [PSV] = 10.1%-24.8%; mean correlations [R] = 0.34-0.36; mean p = 0.015-0.026). Furthermore, greater patella lateral alignment, lateral tilt, and lateral spin were associated with longer T times at 3 years (PSV = 11.0%-14.4%, R = 0.39-0.44, p = 0.017-0.028). Last, a higher patella was associated with a lower KOOS at baseline and at 3 years (R = -0.33 to -0.35). The study suggests that patella malalignment is a risk factor for worsening cartilage health, informing clinicians of a better rehabilitation program that targets PFJ degeneration.
Topics: Male; Humans; Patella; Self Report; Cross-Sectional Studies; Patellofemoral Joint; Cartilage; Osteoarthritis, Knee; Magnetic Resonance Imaging; Bone Diseases; Cartilage, Articular; Knee Joint
PubMed: 35598282
DOI: 10.1002/jor.25384