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Acta Bio-medica : Atenei Parmensis May 2020The medial patellofemoral ligament (MPFL) is the most important structure commonly injured during lateral patellar dislocation and its rupture accounts for 3% of total... (Review)
Review
BACKGROUND AND AIM
The medial patellofemoral ligament (MPFL) is the most important structure commonly injured during lateral patellar dislocation and its rupture accounts for 3% of total knee injuries. MPFL reconstruction (MPFLR) is a reliable procedure with good results but variable rates of recurrent instability. The aim of this study is to underline the proper indications for the MPFLR reconstruction and to explain all the pearls and pitfalls regarding the MPFLR both in our experience and found in the latest literature.
METHODS
A comprehensive search in the latest literature using various combinations of the keywords MPFL, MPFLR, dislocation, treatment was performed. The following data were extracted: diagnosis methods, indications and contraindications for isolated MPFLR, type of management, recurrence of instability, outcomes and complications.
RESULTS
History of multiple patellar dislocations is the most relevant indication for ligament reconstruction especially after a failed course of conservative treatment in presence of persistent patello-femoral instability. Gold standard technique for MPFLR has not been clearly defined yet.
CONCLUSIONS
There is still poor literature about outcome comparisons, therefore it is challenging to decide which technique is the most appropriate as surgical procedures are continuously developing. The ideal candidates for MPFLR have to be decided after a throughout evaluation and careful planning and, with nowadays knowledge, it is possible to put indication for a reconstruction exposing the patient to minimal risks.
Topics: Humans; Joint Instability; Ligaments, Articular; Orthopedic Procedures; Patellofemoral Joint; Treatment Outcome
PubMed: 32555079
DOI: 10.23750/abm.v91i4-S.9669 -
Arthroscopy Techniques Oct 2022Patellar dislocations are common injuries in the pediatric and adolescent population, with an estimated mean incidence of 42/100,000 person-years. The medial...
Patellar dislocations are common injuries in the pediatric and adolescent population, with an estimated mean incidence of 42/100,000 person-years. The medial patellofemoral ligament is the most important structure preventing lateral patellar translation, whereas its patellar attachment is frequently damaged after patellar dislocations. This technical note presents an all-arthroscopic medial patellofemoral ligament repair technique suggested after a first episode of patellar dislocation.
PubMed: 36311312
DOI: 10.1016/j.eats.2022.05.015 -
Archives of Orthopaedic and Trauma... Oct 2021The purpose of this study was to describe the indications and technical aspects as well as evaluate the clinical and functional outcome of lengthening osteotomy of the...
INTRODUCTION
The purpose of this study was to describe the indications and technical aspects as well as evaluate the clinical and functional outcome of lengthening osteotomy of the lateral trochlear ridge in patients with patellofemoral pain and/or patella instability and presence of trochlear dysplasia Dejour type A or lack of Dejour type dysplasia and short lateral articular trochlea.
MATERIALS AND METHODS
Six consecutive adult patients were treated with a lateral trochlear lengthening osteotomy. Five patients received a concomitant medial patellofemoral ligament reconstruction. Three patients had prior patella stabilization surgeries. Trochlea dysplasia (Dejour classification), Caton-Dechamps index, tibial tubercle trochlear groove (TT-TG) distance, patellar tilt and lateral condylar index were measured in preoperative MRIs. Clinical and functional evaluation included the Kujala Anterior Knee Pain Scale, the Lysholm Knee Score, the Tegner Activity Score, a subjective evaluation form and isokinetic muscle strength.
RESULTS
Four patients had a Dejour type A dysplasia, two patients had no dysplasia. The mean (range) Caton-Dechamps index was 1.09 (0.95-1.16), TT-TG distance 10.9 mm (9.2-15.6 mm), patellar tilt 15° (4-32°) and lateral condylar index 82.0% (74-90%). One patient was lost to follow up, all others were followed for 2-5 years. All patients were satisfied with the clinical outcome. The Lysholm score increased from 55 (37-79) to 89 (76-100), the Tegner activity score from 3.6 (2-6) to 5.6 (5-7). The Kujala score postoperative was 90 (75-96). Some but not all patients had full strength recovery compared to the contralateral leg.
CONCLUSION
We recommend measuring the lateral condylar index and considering the indication of a lateral trochlear lengthening osteotomy as an additional or isolated procedure in selected patients with trochlear dysplasia Dejour type A or lack of dysplasia and short lateral articular trochlea depending on the extent of the patellar instability.
LEVEL OF EVIDENCE
Level IV, Case Series.
TRIAL REGISTRATION NUMBER
NCT04378491, clinicaltrials.gov, May 7, 2020.
Topics: Adult; Humans; Joint Instability; Knee Joint; Ligaments, Articular; Osteotomy; Patella; Patellar Dislocation; Patellofemoral Joint
PubMed: 33625541
DOI: 10.1007/s00402-020-03736-5 -
Life (Basel, Switzerland) Dec 2021Chondral and soft tissue injuries can be associated with first time patellar dislocation, but it is unclear how common they are, and which tissues are affected. A... (Review)
Review
INTRODUCTION
Chondral and soft tissue injuries can be associated with first time patellar dislocation, but it is unclear how common they are, and which tissues are affected. A systematic review of the literature was performed to investigate the frequency, location, and extent of chondral and medial patellofemoral ligament (MPFL) injuries in patients following first time patellar dislocation.
METHODS
This systematic review was conducted according to the PRISMA guidelines. PubMed, Google Scholar, Embase, and Web of Science databases were accessed in November 2021. All the published clinical studies reporting the frequency, location, and extent of soft tissue lesions following first time patellar dislocation were accessed. Studies reporting data on habitual, congenital, or recurrent patellofemoral instability were excluded.
RESULTS
Data from 42 articles (2254 patients, mean age 21.6 ± 7.3 years) were retrieved. Ninety-eight percent of patients who experienced first time patellar dislocation demonstrated MPFL rupture at MRI. Forty-eight percent of MPFL ruptures were located at the patellar side, 34% at the femoral insertion site, and 18% in the midportion. Eighty-five percent of patients showed signs of patellar chondral damage at MRI, and trochlear chondral injuries were evidenced in 47% of patients. Intra-articular loose bodies were observed in 11.5% of patients. At arthroscopy, the medial facet and the crest of the patella more commonly exhibited chondral lesions than the lateral facet and femoral trochlea.
CONCLUSIONS
Most patients suffer chondral damage and MPFL tears following after a first time patellar dislocation.
PubMed: 34947891
DOI: 10.3390/life11121360 -
RoFo : Fortschritte Auf Dem Gebiete Der... Sep 2021Throughout the literature, patellofemoral instability (PI) is defined as an increased risk of re-/luxation of the patella within the patellofemoral joint (PFJ). In... (Review)
Review
BACKGROUND
Throughout the literature, patellofemoral instability (PI) is defined as an increased risk of re-/luxation of the patella within the patellofemoral joint (PFJ). In most patients it is caused by traumatic patella luxation or the existence of a range of predisposing anatomic risk factors leading to an unphysiological movement sequence within the PFJ also known as patellofemoral maltracking. In order to provide an individualized therapy approach, clinical and radiological evaluation of those risk factors of variable magnitude becomes essential. Diagnostic imaging such as magnetic resonance imaging (MRI), plain radiography, and computed tomography (CT) are straightforward diagnostic tools in terms of evaluation and treatment of PI.
METHOD
In this review we performed a precise analysis of today's literature concerning the radiological evaluation of anatomic risk factors leading to PI. The purpose of the review is to present a logical compilation of the different anatomical risk factors causing PI and provide a straight overview of valuable radiological imaging techniques.
RESULTS AND CONCLUSION
PI is frequently based on a multifactorial disposition. The most relevant predisposing risk factors are trochlea dysplasia, rupture of the medial patellofemoral ligament (MPFL), patella alta, abnormal tibial tubercle to trochlea groove distance (TT-TG), femoral torsion deformities, and genu valgum. Although plain X-rays may provide basic diagnostic value, cross-sectional imaging (MRI, CT) is the standard radiological tool in terms of evaluation and detection of severity of predisposing anatomic variants leading to PI.
KEY POINTS
· Based on today's literature, PI is characterized as an increased risk of patella re-/luxation within the PFJ.. · Underlying anatomic risk factors of variable magnitude mark the pathological cause of PI.. · Modern diagnostic imaging (MRI and CT) permits straightforward diagnosis of the typical features in terms of PI.. · To provide an individualized therapy approach, precise radiological evaluation and determination of the severity of predisposing anatomic anomalies are essential..
CITATION FORMAT
· Maas KJ, Warncke ML, Leiderer M et al. Diagnostic Imaging of Patellofemoral Instability. Fortschr Röntgenstr 2021; 193: 1019 - 1033.
Topics: Humans; Ligaments, Articular; Magnetic Resonance Imaging; Patella; Patellar Dislocation; Patellofemoral Joint; Tibia
PubMed: 33773517
DOI: 10.1055/a-1348-2122 -
Orthopaedics & Traumatology, Surgery &... Feb 2022Trochlear dysplasia consists in deficient trochlear concavity, giving rise to a flat or convex trochlea, and is the main risk factor for patellar dislocation. Surgical... (Review)
Review
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. It gives good results in terms of recurrence of dislocation, but tends to cause knee stiffness and patellofemoral osteoarthritis. Indications are based on objective patellar instability associated to high-grade B or D dysplasia. Medial patellofemoral ligament reconstruction should be systematically associated. The lateral retinaculum is systematically sectioned, as patellar tilt is never reducible in such high-grade dysplasia. Trochleoplasty corrects the sulcus defect, resolves protrusion and enables proximal realignment. The main complications are stiffness and pain due to persistence or onset of cartilage lesions. Trochleoplasty is indicated: 1) in first line for objective patellar instability associated with high-grade dysplasia; or 2) for recurrence in high-grade dysplasia previously managed by other surgery. The aim of the present study was to review the literature on trochleoplasty and address the following questions: how to define high-grade dysplasia? What are the key clinical and radiologic points? What are the risk factors for patellar dislocation? What trochleoplasty techniques are available? What results can be expected? Level of evidence: V; expert opinion.
Topics: Femur; Humans; Joint Instability; Ligaments, Articular; Patellar Dislocation; Patellofemoral Joint
PubMed: 34863959
DOI: 10.1016/j.otsr.2021.103160 -
Orthopaedic Journal of Sports Medicine Nov 2022Patellar dislocation is attracting considerable research interest. (Review)
Review
BACKGROUND
Patellar dislocation is attracting considerable research interest.
PURPOSE
To assess studies on patellar dislocation using a scientometric method to better understand the current status of research and explore future study directions.
STUDY DESIGN
Scoping review.
METHODS
The Web of Science Core Collection database was selected to retrieve publications on patellar dislocation. Articles and reviews written in English with patellar dislocation as the main topic were included. Conference abstracts, notes, letters, expert opinions, and animal studies were excluded. A total of 4632 articles were identified in our initial search. In addition, Excel 2019, CiteSpace 6.1.R1, and VOSviewer 1.6.9 were used to analyze the -index, the most highly cited publication, publication essentials, and research themes.
RESULTS
A total of 1485 articles were included in our analysis, with 36,608 citations and an -index of 93. Overall, 1494 institutions and 195 journals were identified from these studies. The United States (n = 531) was the most productive country. The institution and journal with the largest number of articles were the Hospital for Special Surgery (n = 59) and (n = 212), respectively. The article "Scoring of Patellofemoral Disorders" by Kujala et al in 1993 was the most highly cited reference. The most commonly found terms used were , , , , , and . Four topics were identified after clustering analysis of key terms: risk factors, medial patellofemoral ligament reconstruction, patellar dislocation in skeletally immature patients, and lateral retinacular release.
CONCLUSION
This scientometric review of articles on patellar dislocation summarized the current status of research (countries, institutions, and authors) and identified potential research directions.
PubMed: 36452338
DOI: 10.1177/23259671221137051 -
Journal of Orthopaedics Oct 2024Hypermobility describes the movement of joints beyond normal limits. Whether hypermobility predisposes to patellar instability is yet to be established. We aimed to... (Review)
Review
INTRODUCTION
Hypermobility describes the movement of joints beyond normal limits. Whether hypermobility predisposes to patellar instability is yet to be established. We aimed to determine if joint hypermobility leads to an increased risk of patellar instability, and to evaluate outcomes of treatment for patellar instability in those who exhibit hypermobility.
METHODS
Published and unpublished literature databases were searched to September 7, 2023. Studies comparing prevalence of patellar dislocation/differences in treatment outcomes in patients with and without hypermobility were included.
RESULTS
We identified 18 eligible studies (4,391 patients). The evidence was low in quality. A case series on 82 patients found that there was a relationship between generalised joint laxity and patellar instability. This was corroborated by a study comparing 104 patients with patellar dislocation to 110 patients without. Prevalence of generalised joint laxity was six time higher in the former (64.4% vs 10.9%, p < 0.001).Five studies found surgical intervention aimed at correcting patellar dislocation in patients with idiopathic hypermobility led to satisfactory outcomes. There was conflicting evidence regarding if hypermobile patients have worse outcomes than non-hypermobile patients following medial patellofemoral ligament reconstruction (MPFLR) in two studies. In addition, this procedure had a 19.1% failure rate in patients with Ehlers Danlos Syndrome (EDS), with hypermobility associated with a higher failure rate (p = 0.03). One study showed the type of graft used made no difference in outcome scores or re-dislocation rates (p > 0.5). Another study had 7/31 (22.6%) autografts which failed, compared to 2/16 allografts (12.5%) (p = 0.69).
CONCLUSION
Joint hypermobility is a risk factor for patellar instability. Identification of at-risk groups may aid prevention of dislocations and allow for appropriate treatment. Patients with EDS experience poor outcomes following patellar stabilization surgery, with post-operative monitoring required.
PubMed: 38784948
DOI: 10.1016/j.jor.2024.05.009 -
Current Reviews in Musculoskeletal... Nov 2023Obligatory dislocation of the patella (also known as habitual dislocation) is a rare subset of patellofemoral instability in which the patella dislocates every time the... (Review)
Review
PURPOSE OF REVIEW
Obligatory dislocation of the patella (also known as habitual dislocation) is a rare subset of patellofemoral instability in which the patella dislocates every time the knee is flexed. The problem arises due to contracture of the quadriceps muscles. Soft tissue lengthening procedures such as quadriceps tendon lengthening are the mainstay of treatment, in contrast to medial patellofemoral reconstruction (MPFL-R) for the more common recurrent lateral patellar dislocation. The current review explores the existing literature surrounding the pathophysiology and treatment strategies for this unique cause of knee instability.
RECENT FINDINGS
Flexion dislocation of the knee often presents in children when they begin to walk. It is also termed obligatory or habitual because the patella dislocates laterally with each flexion and extension cycle of the knee. In contrast to other forms of patellar dislocation, the displacement is painless in obligatory dislocation. Likewise, the underlying biomechanical cause of this issue is related to contracture of tissues lateral to the patella rather than disruption of medial soft tissues as seen in recurrent/traumatic dislocation or subluxation of the patella. A number of procedures have been described for management of obligatory dislocation of the patella, with the general consensus that a combination of procedures including release/lengthening of the proximal lateral soft tissues as a critical component for a successful outcome. Soft tissue release/lengthening has been performed for over 50 years to treat obligatory dislocation of the patella. This procedure must be used in combination with other proximal and distal reconstructive with careful intraoperative assessment of knee flexion and patellar tracking for satisfactory outcomes. Further research using standardized outcome measures is needed to identify the optimal step-wise approach in treatment of obligatory patellar dislocation.
PubMed: 37665483
DOI: 10.1007/s12178-023-09865-9 -
Joints Sep 2019First patellar dislocation is a common injury of the knee, involving often adolescents and the active population. The consequences of the first episode can be various... (Review)
Review
First patellar dislocation is a common injury of the knee, involving often adolescents and the active population. The consequences of the first episode can be various and potentially disabling. Among these, acute patellar dislocation can often result in recurrent patellar instability. Recurrent patellar instability is certainly multifactorial but depends primarily on the injury of the medial patellofemoral ligament (MPFL), the major soft-tissue stabilizer of the patella. Some classifications are extremely useful in establishing the diagnosis and therapy in patellofemoral disease, in particular in terms of instability. Among those, Henri Dejour and WARPS (weak atraumatic risky anatomy pain and subluxation)/STAID (strong traumatic anatomy normal instability and dislocation) classifications are certainly the most frequently used. There is no clear agreement on the management of the first patellar dislocation. A conservative approach seems to be the first choice in most of cases, but the presence of patellar displacement or osteochondral fractures makes surgery mandatory at the beginning. In addition, there is no clear consensus on which surgical strategy should be used to approach first dislocation, in relation to the possible variation in location of the MPFL injury, and to the eventual presence of preexisting predisposing factors for patellar instability. MPFL reconstruction may theoretically be more reliable than repair, while there is no clear evidence available that osseous abnormality should be addressed after the first episode of patellar dislocation. A narrative review was conducted to report the etiology, the diagnosis and all the possible treatment options of the first patellar dislocation. Modern classifications of the patellofemoral instability were also presented.
PubMed: 34195538
DOI: 10.1055/s-0039-3401817