Clinical features and classification of bipartite or tripartite patella

Conventional Radiography Assessment of the Pediatric Knee: Pearls and Pitfalls

Knee pain is one of the most common indications for radiography in the evaluation of musculoskeletal disorders in children and adolescents. According to international guidelines, knee radiographs should be obtained when there is the suspicion of an effusion, limited motion, pain to palpation, inability to bear weight, mechanical symptoms (such as "locking"), and persistent knee pain after therapy. When indicated, radiographs can provide crucial information for the clinical decision-making process. Because of the developmental changes occurring in the knee during growth, the assessment of knee radiographs can be challenging in children and adolescents. Radiologists unfamiliar with the appearance of the knee on radiographs during skeletal maturation risk overcalling or overlooking bone lesions. Image acquisition techniques and parameters should be adapted to children. This article describes the most common challenges in distinguishing pathology from the normal appearance of knee radiographs in the pediatric population, offering some pearls and pitfalls that can be useful in clinical practice.

Painful knee

INTRODUCTION

A bipartite patella is a rare anatomical variant of the patella. A patella bipartite is often asymptomatic and is often an incidental finding on radiological imaging. The patella remains bipartite when secondary ossification centers fail to fuse. Herein, a case of bipartite patella improved after knee arthroscopy and surgical removal.

PRESENTATION OF THE CASE

A 57-year-old male with a history of polytrauma. He complained of progressive pain in the right knee area. A radiological investigation reported a right bipartite patella. The condition improved after the open removal of the accessory patella.

DISCUSSION

This case is considered type III according to Saupe's classification. Due to its location and radiological appearance, it is a painful synchondrosis of a bipartite patella.

CONCLUSION

After the failure of conservative management, the removal of the bipartite patella was necessary and unavoidable to restore everyday activities.

Multipartite patella: A review of diagnostic techniques and management of the symptomatic patient

Multipartite patella is an anatomical variant classified by the fragmentation of the main patellar body. The cause of this variant is due to failure in fusion of the patellar ossification centers. It is commonly misdiagnosed as a fracture of the patella in clinical practice, leading to unnecessary treatment measures. The aim of this review is to provide an overview of the development and classification of this variation, diagnostic imaging techniques, and assess the optimal management technique for the symptomatic patient. Multiple radiographic methods are used to identify this variant, with recent studies highlighting high sensitivity rates for nonradiative methods (ultrasound). In terms of symptomatic management, accessory fragment excision and vastus lateralis release provide the greatest alleviation of symptoms, with screw fixation being less favorable.

Accessory fragment migration in a professional baseball player with bipartite patella: A case report

INTRODUCTION

Bipartite patella (BP) is usually recognized as an incidental radiographic finding. Therefore, no reports have observed the process of accessory fragment migration. We present the case of a professional baseball pitcher with significant migration of the fragment during follow-up.

PRESENTATION OF CASE

A 26-year-old man was diagnosed with symptomatic BP and underwent conservative therapy. Eleven months later, he was unable to play baseball because of gradually worsening knee pain without obvious trauma. On radiographs, the accessory fragment which had located at the superolateral pole 11 months earlier migrated posterolaterally. The diagnosis of Saupe's type III BP was established, and open excision of the accessory fragment was performed. Postoperatively, full-weight-bearing walking and range-of-motion exercises were started the day after surgery. Three months after surgery, he could pitch with all his power without pain.

DISCUSSION

Since our patient was a professional baseball right-handed pitcher who needed to step strongly on his left knee during pitching, strong traction force from the vastus lateralis was likely to have been repeatedly applied to the accessory fragment. It might lead to migration of the accessory fragment. The open excision of the accessory fragment was performed because the accessory fragment had migrated away from the patella body.

CONCLUSION

We report a case of professional baseball player with symptomatic BP, in which case the chronological migration of the accessory fragment was observed without obvious trauma. When the accessory fragment is identified without obvious trauma, one of the differential diseases could be a BP.

The Effect of Patellofemoral Maltracking and Patella Type on Symptomatic Bipartite Patella

Purpose The aim of this study is to investigate the relationship of trochlear dysplasia (TD) and patella type with bipartite patella (BP). Materials and methods A total of 5,081 knee MRIs taken in our institution were reviewed retrospectively. Patients with a history of knee surgery, previous or recent trauma, and rheumatologic involvement were excluded from the study. The MRIs of 49 patients with bipartite/multipartite patella were detected. Three patients were excluded: two patients had a tripartite variant, and one had multiple osseous dysplastic findings. Overall, 46 patients with BP were included in the study. BPs were classified as type I, II, and III. Patients were divided into symptomatic and asymptomatic groups according to the presence of edema within the bipartite fragment and adjacent patella. Patients were examined in terms of patella type, trochlear dysplasia, tuberosity-trochlear groove (TT-TG) difference, sulcus angle, and sulcus depth. Results There were 46 patients with BP (28 males and 18 females) (mean age: 33±9.5 years, range: 18-54). Thirty-eight bipartite fragments (82.6%) were type III and eight (17.4%) were type II. There was no type I BP. Seventeen (36.9%) were symptomatic, and 29 (63.1%) were asymptomatic. Seven of the type II (87.5%) and 10 of the type III (26.3%) bipartite fragments were symptomatic. The frequency and degree of trochlear dysplasia (p=0.007 and p=0.041, respectively) were found to be higher in symptomatic patients. The trochlear sulcus angle was higher (p=0.007) and the trochlear depth was lower (p=0.006) in the symptomatic group. No statistically significant difference was found (p=0.247) in terms of TT-TG difference. Type III and type IV patella were more common in the symptomatic group. Conclusion The current study shows that patellofemoral instability and patella type are associated with symptomatic BP. Patients with trochlear dysplasia, type II BP, and disproportionate patellar facet may have a significantly increased risk of symptomatic BP.

Painful bipartite patella following injury: a case report

Bipartite patella is a normal variation in ossification development. This variation is usually asymptomatic but can cause persistent and debilitating anterior knee pain with an injury. We report the case of a 56-year-old man complaining of persistent anterior left knee pain following trauma. Standard knee radiographs show a bilateral Bipartite Patella appearance, and magnetic resonance imaging shows discrete bony edema of the cancellous bone of the accessory bone and about the synchondrosis explaining the anterior knee pain, associated with a crack in the posterior compartment of the medial meniscus. Conservative care including medical treatment with non-steroidal anti-inflammatory drugs, physical therapy was used. Magnetic resonance imaging is the most valuable diagnostic tool for evaluating detailed morphologic and pathologic changes in patients with the bipartite patella.

Arthroscopic Management for Bipartite Patella: A Systematic Review

Background:

Bipartite patella is a rare congenital condition that becomes painful following direct trauma or an overuse injury. If it remains painful despite nonoperative treatment, surgery may be warranted. The current gold standard is open fragment excision or lateral release; however, arthroscopic management is also possible.

Purpose:

To investigate the safety and efficacy of arthroscopic treatment of painful bipartite patella.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

Using Medline and Embase, we systematically reviewed the literature as of March 8, 2020, using the subject headings “bipartite patella” and “arthroscopy” and related key terms. All levels of evidence involving human studies in English were included. Articles were excluded if only the abstract was published or the study was related to nonsurgical treatment or nonrelated diagnoses. Data related to journal/article information, demographic/clinical data, arthroscopic technique, length of follow-up, treatment outcomes, and complications were extracted.

Results:

Eleven articles with 43 patients were included in the review. Most patients (n = 34; 79%) underwent arthroscopic lateral release, while 16% (n = 7) had arthroscopic excision of the accessory fragment and 5% (n = 2) had arthroscopic excision and release. All patients except for one, who experienced postoperative trauma, were pain-free after arthroscopic treatment and were able to return to sports after a mean 2.6 months.

Conclusion:

This review demonstrated that arthroscopic management of painful bipartite patella is a safe and effective alternative to open surgical excision or release. However, all articles were case studies or small case series, owing to the rarity of the condition. In the future, higher-level studies comparing arthroscopic techniques and postoperative rehabilitation programs should be performed.

Fabella and patella variants: radiographic prevalence, distribution and clinical relevance in a population of black african descent

To evaluate the radiographic characteristics and prevalence of fabella and patella variants in an indigenous African population. This retrospective observational study of orthogonal knee radiographs of 377 consecutive subjects was conducted in Lagos, Nigeria, from February 2017 to November 2017. The presence of bipartite/multipartite patella, as well as the presence of fabella were noted. The craniocaudal diameter, anteroposterior diameter, fabello-femoral distance and fabello-tibial distance of the fabella were measured. P≤0.05 represented a statistically significant result. Three hundred and seventy-seven subjects were enrolled. The average age was 41.22±21.37 years with a range of 3-100 years old. There were 158 male (41.9%) and 219 female (58.1%) subjects. The prevalence of fabella was 11.94%. There was a positive correlation between age <47 and ≥47 and occurrence of fabella, P<0.015. There was no statistically significant difference between the mean male and female measured fabella diameters. The overall prevalence of bipartite and multipartite patella in this study was 2.12%. Among male and female subjects, the difference in prevalence of bi and multipartite patella was statistically significantly, P=0.03. The prevalence of fabella and patella variants was lower in this study compared to the findings in other populations and ethnicities. Sex and age were significantly correlated with fabella prevalence. The results reported in this study will facilitate future studies examining the correlations between fabella and patella variants and various knee pathologies in a population of Black African descent.

Arthroscopic Excision of Bipartite Patella

A bipartite patella usually presents as an incidental finding on radiographs because most cases are asymptomatic. However, some patients may present with pain and functional limitations. Conservative treatment is sufficient to resolve symptoms in most cases; however, a small minority of patients may require surgical management. Recent studies have reported excellent results with an arthroscopic approach. This Technical Note details our procedure for treating a symptomatic bipartite patella that has not resolved with conservative care.

Intra-osseous tophaceous gout of a bipartite patella mimicking aggressive bone tumour

This is a very rare case of gouty tophus in the patella of a 31-year-old male, without any medical co-morbidities. The patient initially presented after an injury to left knee but came back months later due to persistence of pain. Surgical decision was made based on imaging findings in computed tomography and magnetic resonance imaging of an intraosseous lesion that has increased in size. The initial diagnosis is that of an aggressive bone tumour. The diagnosis of an intraosseous gout was made intra-operatively upon seeing the characteristics of the lesion, and upon confirmation of the biopsy results. Gout can usually be managed medically with urate lowering drugs and lifestyle change. However, when presented with a tophus that is increasing in size and causing mass effect on the involved bone, surgical management is indicated.

New variant of bipartite patella with traumatic separation and complete disruption of the extensor mechanism of the knee

Very few case reports have been reported on traumatic separation of the bipartite patella along with quadriceps tendon rupture. These reports relate to separation of superolateral bipartite patella (Saupe type 3). We describe a new variant which to our knowledge has not been described or classified so far, which is purely a superior bipartite patella with traumatic separation and complete functional disruption of the extensor mechanism of the knee in a young patient working in the army which was managed with open reduction and internal fixation along with repair of the extensor mechanism of the knee achieving complete functional recovery.

Clinical Features and Radiological Differential Diagnoses of Symptomatic Sesamoid Bones and Accessory Ossicles: A Pictorial Essay

종자골과 부골은 정상 해부학적 변이로 그 빈도와 형태는 다양하며 일반적으로 크기가 작고 둥근 모양으로 피질로 잘 둘러싸여 있고 뼈나 관절 주위에 인접하여 관찰되고 드물게 이분 혹은 다분 형태를 보일 수 있다. 대부분의 종자골과 부골은 무증상이며 판독 업무 중에 흔히 마주치게 된다. 하지만 때때로 종자골과 부골이 증상을 일으킬 수 있는데, 종자골과 부골 자체의 골절이나 탈구, 관절염, 골괴사, 감염 등의 질환이 이환되거나, 주변에 신경압박이나 건초염, 연부조직의 포착 등에 의하여 증상을 유발할 수 있다. 이 종설에서는 다양한 해부학적 위치에서 발생한 증상이 있는 종자골과 부골의 영상을 보고, 이들의 임상적 양상과 영상의학적 감별진단을 정리해보고자 한다.

Analyses of the neandertal patellae from El Sidrón (Asturias, Spain) with implications for the evolution of body form in Homo

The evolution of the body form in Homo and its potential morphological connection to the arrangement of different skeletal systems is of major interest in human evolution. Patella morphology as part of the knee is potentially influenced by body form. Here, we describe for the first time the patellae remains recovered at El Sidrón Neandertal site and analyze them in a comparative evolutionary framework. We aim to clarify whether morphometric features frequently observed in Neandertal and modern human patellae are retained from a primitive anatomical arrangement or whether they represent derived features (apomorphies). For this purpose, we combine analyses of discrete features, classic anthropological measurements, and 3D geometric morphometrics based on generalized Procrustes analysis, mean size and shape comparisons, and principal components analysis. We found a size increment of the patella in hominin evolution, with large species showing a larger patella. Modern humans and Neandertals exhibit overall larger patellae, with maximum values observed in the latter, likely as a consequence of their broader body shape. Also, some Neandertals display a thicker patella, which has been linked to larger quadriceps muscles. However, Neandertals retain a primitive morphology in their patellar articular surfaces, with similar-sized lateral and medial articular facets, leading to a more symmetrical internal face. This feature is inherited from a primitive Homo ancestor and suggests a different configuration of the knee in Neandertals. Conversely, Homo sapiens exhibits an autoapomorphic patellar anatomy with expanded lateral articular facets. We propose that these distinct configurations of the patella within Homo may be a consequence of different body forms rather than specific functional adaptations of the knee. Thus, the slender body form of modern humans may entail a medial reorientation of the tibial tuberosity (patellar ligament), allowing lateral surface expansion. These anatomical evolutionary variations may involve subtle secondary differences in bipedalism within Homo.

Magnetic resonance imaging for diagnosis of bipartite patella: usefulness and relationship with symptoms

Purpose

Bipartite patella is a rare developmental variation of the knee cap. We aimed to identify the magnetic resonance imaging (MRI) features of bipartite patella and evaluate the association with clinical symptoms.

Material and methods

MRI exams of 61 patients with bipartite variant were evaluated for types of bipartite patella, oedema around the synchondrosis, bipartite fragment height (FH), distance between the fragment and the patella (FPD), and signal characteristics within the synchondrosis. The study was designed with two observers in order to achieve intra- and interobserver compliance. Any other major knee pathologies that can cause pain were also recorded.

Results

Of the 61 participants the average age was 40.1 ± 14.3 years, 44 were males, and 17 were females. Fifty-nine of the bipartite fragments were located at the superolateral quadrant of the patella. There was oedema at the bipartite area in 35 patients. Ten of these patients had no major MRI diagnosis other than oedema, and they were classified as the symptomatic group. The age of the patients in the symptomatic group was statistically lower than in the asymptomatic group (p < 0.05). There was no statistically significant difference between the groups in terms of male and female distributions, signal types across the synchondrosis, and FH or FPD measurements (p > 0.05). High concordance correlation coefficients were observed on measurements.

Conclusions

MRI of the knee is highly accurate in evaluation of bipartite patella. To our knowledge; a detailed MRI analysis, like in our study, has not previously been performed, and our report is unique in showing that the symptomatic occurrence of bipartite patella is statistically higher in young patients.

Ultrasound-guided injection and the pie crust technique for the treatment of symptomatic bipartite patella

PURPOSE

This study aimed to investigate the results of a new treatment procedure (ultrasound-guided injection and the "pie crust" technique for lengthening of capsular tendon structures) for symptomatic bipartite patella.

METHODS

We retrospectively investigated patient outcomes following the treatment of symptomatic type III bipartite patella with our new technique. Fifteen knees in 14 boys (mean age, 13.0 ± 1.7 years) were included. The procedure involved the injection of 1% lidocaine (2 mL) and triamcinolone acetonide (5 mg) between the patella and fragment. We then punctured 10 sites from one skin puncture to extend lateral capsular tendon structures. The patients were clinically assessed using the Victorian Institute of Sports Assessment (VISA) score before and 1 week, 1 month, and 3 months after the procedure. Patients were also evaluated for complications.

RESULTS

The average VISA score was 45.7 ± 4.7 before treatment, 70.6 ± 7.3 at 1 week post-treatment, 84.4 ± 16.6 at 1 month post-treatment, and 88.6 ± 18.3 at 3 months post-treatment. The VISA score improvement from before the procedure to 1 week after the procedure was significant (P < 0.01). There were no complications in any of the patients, who returned to sports at a mean of 4.2 ± 2.1 weeks after the procedure. However, two patients (three knees) had poor results and could not return to action; thus, they underwent surgical treatment 4 months after the ultrasonographic procedure.

CONCLUSIONS

This novel method is a potential treatment option for the management of symptomatic bipartite patella in outpatient clinics.

Skeletal Anomalies in The Neandertal Family of El Sidrón (Spain) Support A Role of Inbreeding in Neandertal Extinction

Neandertals disappeared from the fossil record around 40,000 bp, after a demographic history of small and isolated groups with high but variable levels of inbreeding, and episodes of interbreeding with other Paleolithic hominins. It is reasonable to expect that high levels of endogamy could be expressed in the skeleton of at least some Neandertal groups. Genetic studies indicate that the 13 individuals from the site of El Sidrón, Spain, dated around 49,000 bp, constituted a closely related kin group, making these Neandertals an appropriate case study for the observation of skeletal signs of inbreeding. We present the complete study of the 1674 identified skeletal specimens from El Sidrón. Altogether, 17 congenital anomalies were observed (narrowing of the internal nasal fossa, retained deciduous canine, clefts of the first cervical vertebra, unilateral hypoplasia of the second cervical vertebra, clefting of the twelfth thoracic vertebra, diminutive thoracic or lumbar rib, os centrale carpi and bipartite scaphoid, tripartite patella, left foot anomaly and cuboid-navicular coalition), with at least four individuals presenting congenital conditions (clefts of the first cervical vertebra). At 49,000 years ago, the Neandertals from El Sidrón, with genetic and skeletal evidence of inbreeding, could be representative of the beginning of the demographic collapse of this hominin phenotype.

Synchondrosis Bither Block: A New Addition in the Diagnosis of Symptomatic Bipartite Patella

Symptomatic bipartite patella is uncommon, and to ensure good outcome, patient selection is the key. Mostly assigning the pain origin to the nonfused fragment is easy though, in few cases, can be a serious dilemma, especially in the absence of direct tenderness over nonfused fragment. The decision of surgical intervention is solely made on the criteria of exclusion of other causes in the presence of persistent anterior knee pain. The literature focuses on different treatment techniques and outcomes with a rare attempt to add to the currently available supporting tests to affirmatively ascertain the cause-pain relation to the bipartite fragment. This article defines the synchondrosis block to assist the surgeon in isolating the source of pain to bipartite fragment in symptomatic knee.

Bipartite patella separation and partial quadriceps tendon rupture in the setting of trauma

Normal development of the patella typically involves fusion of secondary ossification centers into a single bone during adolescence, with failure of fusion resulting in bipartite and tripartite patellae. In such variants, injury to incomplete ossification center fusion, though uncommon, has been reported to occur in the setting of traumatic quadriceps tendon rupture. The authors present a rare and complex case of traumatic bipartite fragment separation, patellar avulsion, and a complex partial quadriceps tendon tear confirmed surgically in a 36-year-old male. In this case, a tear in the lateral aspect of the quadriceps tendon attached to the nonfused patellar ossification center resulted in retraction of the band containing the bipartite fragment and separation of the patellar fragments, with superior displacement of the smaller bony avulsion likely due to complex attachments from the medial aspect of the quadriceps tendon. Knowledge of the classical locations of a bipartite and tripartite patella can aid in the differentiation of the anatomic variant versus patellar avulsion. Additionally, knowledge of the variable and complex nature of the quadriceps tendon aids in understanding the process of patellar avulsions and various tears, leading to the appropriate orthopedic management.

Acute presentation of Sinding-Larsen-Johansson disease simulating patella sleeve fracture: A case report

OBJECTIVES

Diagnosis of Sinding-Larsen-Johansson disease may not be an easy task. Several sport-related conditions affect the distal pole of the patella in the adolescent, and treatment varies considerably. The article describes a patient that had radiographic features of Sinding-Larsen-Johansson disease associated with an atypical acute presentation.

METHODS

Case report and literature review.

RESULTS

A 10-year-old boy presented with a sudden pain after a noncontact soccer injury. He had tenderness and swelling over the patella. Radiographs showed minimally displaced distal patellar ossicle. Magnetic resonance imaging excluded sleeve cartilaginous injury and documented Sinding-Larsen-Johansson disease. The knee was immobilized briefly. There was complete healing of the injury in 4-week follow-up radiographs.

CONCLUSION

Emergency physicians, radiologists, and orthopedic surgeons should be aware of the acute presentation of Sinding-Larsen-Johansson disease after knee injuries.

The anterior knee: normal variants, common pathologies, and diagnostic pitfalls on MRI

The anterior aspect of the knee is host to an array of normal variants and potential pathology. These normal anatomic variants are often encountered and may mimic pathologies, leading to unnecessary work-up and treatments. On the other hand, there are several subtle abnormalities that may be easily overlooked or mistaken for variants or other injuries or diseases. Recognition of these diagnostic challenges is essential for radiologists to make an accurate diagnosis. This article reviews normal anatomical variants of ligaments, tendons, bones, and other important structures of the anterior knee, focusing on magnetic resonance imaging features. Commonly encountered injuries and abnormalities of the anterior knee and their diagnostic pitfalls are also discussed, highlighting findings on magnetic resonance imaging.

Arthroscopic Bony Resection for Treatment of Symptomatic Bipartite Patella

Bipartite patella is a common pathology, affecting 2% to 3% of the population. Usually these cases are bilateral and asymptomatic. However, a patient with a bipartite patella may complain of pain, which is most likely related to fragment mobility. Conservative treatment with physiotherapy, immobilization, and nonsteroidal drugs are encouraged during the initial 6 months following diagnosis. This option is effective in most patients. For patients who do not improve with these conservative measures, surgical intervention is indicated. Many surgical treatment options have been described including excision of the fragment, as well as fixation. Fragment excision has demonstrated positive outcomes and is associated with an asymptomatic return to sport activities. The purpose of this Technical Note is to describe our preferred arthroscopic technique for the treatment of symptomatic bipartite patella.

Surgical Technique for Arthroscopic Resection of Painful Bipartite Patella

Bipartite patella (BP) is uncommon and is usually an incidental finding. Painful BP occurs rarely and is usually associated with post-traumatic anterior knee pain. When nonoperative treatment fails, fragment resection is indicated. A systematic review shows a potentially increased risk of complications with open surgery. The purpose of this Technical Note is to demonstrate a simple arthroscopic technique for treating painful BP through resection of the bone fragment.

Traumatic Rupture of an Intermediate Tendon in a Patient with Patellar Duplication

Patellar duplication is a rare asymptomatic condition. The diagnosis is often made following a traumatic event associated with an injury to the knee extensor mechanism. The treatment is often surgical and consists in removal of the smaller part of the patella with tendon reinsertion. The presence and rupture of an intermediate tendon between the two parts of the patella have not been reported in the modern literature. We present a traumatic rupture of an intermediate tendon in a patient with horizontal patellar duplication. The surgical management consisted of tenorrhaphy protected with a figure-of-eight tension band wire approximating the two parts of the patella. The patient recovered full knee range of motion and quadriceps strength at the last 8-month follow-up.

Forensic Identification of Bipartite Patella Misdiagnosed as Patella Fracture

Bipartite patella is recognized as a developmental anomaly of ossification. Most of them are asymptomatic and are discovered incidentally. Bipartite patella is sometimes misdiagnosed as a patella fracture, because the x-ray images of both these conditions may appear very similar. In this case, the patient complained of left knee pain after x-ray films revealed a fracture-like line in the left patella. The patient was then diagnosed as having a patella fracture. In China, the injury degree is categorized as serious injury, minor injury, and trivial injury. As the injury degree of patellar fracture is identified as minor injury, the defendant who injured the patient will be sentenced to prison for ≤3 years. However, the defendant objected to this judgment and applied for the second evaluation of injury degree. On the basis of the site of injury, clinical manifestations, and imaging findings, we diagnosed the patient with bipartite patella which belongs to normal anatomic variant. Therefore, the injury degree of the patient was not minor injury.

Arthroscopic treatment of painful Sinding-Larsen-Johansson syndrome in a professional handball player

Sinding-Larsen-Johansson (SLJ) syndrome is a type of osteochondrosis of the distal pole of the patella most often caused by repeated microtrauma. Here, we describe the case of a professional athlete with painful SLJ syndrome treated arthroscopically. A 29-year-old male professional handball player presented with anterior knee pain that persisted after 4 months of an eccentric rehabilitation protocol and platelet-rich plasma injections. Despite this conservative treatment, the patient could not participate in his sport. The SLJ lesion was excised arthroscopically, which led to complete disappearance of symptoms and return to competitive sports after 5 months.

The management of the painful bipartite patella: a systematic review

PURPOSE

This study aimed to identify the most effective method for the treatment of the symptomatic bipartite patella.

METHODS

A systematic review of the literature was completed, and all studies assessing the management of a bipartite patella were included. Owing to the paucity of randomised controlled trials, a narrative review of 22 studies was completed. A range of treatments were assessed: conservative measures, open and arthroscopic fixation or excision and soft tissue release and excision.

RESULTS

All of the methods provided results ranging from good to excellent, with acceptable complication rates.

CONCLUSIONS

This is a poorly answered treatment question. No firm guidance can be given as to the most appropriate method of treating the symptomatic bipartite patella. This study suggests that there are a number of effective treatments with acceptable complication rates and it may be that treatments that conserve the patella are more appropriate for larger fragments.

LEVEL OF EVIDENCE

IV.

Unusual Symptomatic Multipartite Patella Associated with Quadriceps Fat Pad Edema

Partite patella is a known cause of anterior knee pain, especially in adolescents and young males, although most patients are asymptomatic. Symptomatic partite patella is usually revealed on magnetic resonance imaging (MRI) as bone marrow edema within the opposing bone fragments. We present a case of unusual bilateral symptomatic multipartite patella in an adult who presented with quadriceps fat pad edema and mass effect as well as slightly edematous signal changes within the bone fragments on MRI. This case indicates that symptomatic partite patella can also present with edema-like imaging findings in the adjacent soft tissue due to chronic mechanical irritation.

Return to activity among athletes with a symptomatic bipartite patella: a systematic review

BACKGROUND

A bipartite patella is typically rare, but can become symptomatic during overuse activities such as those performed during athletic events. Therefore, this anomaly typically presents in the young, athletic population, often inhibiting athletic activities. Multiple treatment options exist, with nonsurgical management frequently adopted as the initial treatment of choice.

PURPOSE

To determine the most effective intervention in returning athletes with symptomatic bipartite patella to their prior activity levels.

METHODS

A systematic review of the literature was performed using PRISMA guidelines to identify studies reporting outcomes of athletes' ability to return to activity following treatment for a symptomatic bipartite patella. The type of intervention, type of bipartite classification, outcomes, and complications were recorded.

RESULTS

Twenty articles with a total of 125 patients and 130 knees were identified and included in this review. A total of 105 athletes made a full return to athletic activity following treatment for their painful bipartite patella. One hundred athletes (85.5%) that underwent surgical treatment were able to make a full return to their sport without symptoms, although this varied by surgical procedure performed. Excision of the painful fragment produced the best results in returning athletes to sport, with 91% returning without symptoms and nine percent returning but with residual symptoms.

CONCLUSION

Surgical treatments for symptomatic bipartite patellae are successful at returning athletes to their same level of play, and best outcomes are with excision of the fragment. These results are limited, however, due to the poor quality of original data given the rarity of the anomaly and the underrepresented conservative treatment group.

Developmental anomaly of ossification type patella partita

PURPOSE

Bipartite patella has been recognized as an incidental radiographic finding. However, symptomatic bipartite patella is occasionally diagnosed in adolescents and young athletes. The incidence of bipartite patella has been reported at 0.2-1.7, and 1-2 % of these cases are symptomatic. The purpose of this review article was to discuss current concepts relevant to developmental anomaly of ossification type patella partita.

METHODS

A PubMed database search using the key words "bipartite patella" was performed. Clinical papers reporting the bipartite patella were included. Four German-language studies were also included, three for incidence of bipartite patella and one for classification.

RESULTS

A new classification of developmental anomaly of ossification type patella partita based on location and number of fragment was recently proposed. It is simple and useful and applicable to all types of bipartite or tripartite patella. Several imaging studies have reportedly been used to evaluate symptomatic bipartite patella. MRI is currently the most appropriate method used to assess patients with bipartite patella. Although surgical procedures have been developed that reduce excessive traction force by the vastus lateralis muscle on the bipartite fragment, there is not sufficient evidence to support their use for routine treatment of painful bipartite patella.

CONCLUSION

In most symptomatic cases, movement at the interface between the bipartite fragment and the body of the patella presumably causes the pain. Therefore, the existence of apparent motion at the interface should be confirmed by specific imaging studies before surgery. Magnetic resonance imaging findings may provide such evidence by demonstrating a fluid bright signal across the segmentation, typical of pseudoarthrosis.

LEVEL OF EVIDENCE

V.

Tibial tubercle fracture in a 14-year-old athlete with bilateral lower pole bipartite patella and osgood-schlatter disease

We present a case of tibial tubercle fracture in a young male athlete with both bilateral bipartite patella at the lower pole (Saupe type I) and Osgood-Schlatter disease. Open reduction and internal fixation were performed to restore the extensor mechanism of the knee.

MR imaging of anterior knee pain: a pictorial essay

Anterior knee pathology is a frequent cause of joint pain and limitation of function and mobility among patients presenting to an orthopaedic department. Proper recognition and treatment of pathologic conditions depend on the knowledge of normal anatomy and of the various abnormalities, which affect this area of the knee and may present with anterior knee pain. A broad array of benign and malignant processes may be manifested as anterior knee discomfort, and this common clinical entity is among the most frequent indications for MR imaging of the lower extremities. Clinical history and physical examination are also of paramount importance. The disorders can be categorized and differentiated primarily according to their location. Traumatic or non-traumatic disorders of the patella, patellar retinacula, quadriceps and patellar tendons and supra or infrapatellar fat pad can be the source of symptoms. This article includes a comprehensive pictorial essay of the characteristic MR features of common and uncommon disorders causing anterior knee pain. For accurate assessment of the aforementioned clinical problem, a radiologist should be able to identify typical MR imaging patterns that contribute in establishing the correct diagnosis and thus tailoring the appropriate therapy. Level of evidence IV.

Patella fracture in a boy with bilateral inferior pole bipartite patellae

We present the case of a 12 year old boy who had bilateral inferior pole fragment (Saupe type 1) bipartite patellae, and who sustained a traumatic separation through the right patella while playing basket ball, the left remaining asymptomatic. We have reviewed and discussed the previously published literature and case reports.

Arthroscopic treatment of symptomatic bipartite patella

Successful arthroscopic treatment of symptomatic bipartite patella in a 23-year-old female professional volleyball player is reported.

Injury of a bipartite patella in a young upcoming sportsman

The aim of this study was to report the clinical features of a young athletic patient with bipartite patella, and review the literature to discuss the entity of this rare anomaly. In the course of an athletics competition, a 12-year-old top sportsman felt an intense pain around his left knee-cap while taking off from a jumping-board and broke down the competition. X-rays and magnetic resonance imaging showed an isolated distal pole of the patella with just minor diastasis; however, the X-rays did not suggest a recent fracture but rather hint at an atypically injured bipartite patella. A conservative therapy of 5 weeks with brace followed including a ban on sport activities for 12 weeks. Ten weeks later, the radiographs revealed a complete consolidation. Six months after the injury, MRI only presented a generally inconspicuous horizontal sclerosed structure. A fracture or separation of the bipartite patella was retrospectively diagnosed.