Association between patellar cartilage defects and patellofemoral geometry: a matched-pair MRI comparison of patients with and without isolated patellar cartilage defects.

PubMed

Mehl, Julian; Feucht, Matthias J; Bode, Gerrit; Dovi-Akue, David; Südkamp, Norbert P; Niemeyer, Philipp

2016-03-01

To compare the geometry of the patellofemoral joint on magnetic resonance images (MRI) between patients with isolated cartilage defects of the patella and a gender- and age-matched control group of patients without patellar cartilage defects. A total of 43 patients (17 female, 26 male) with arthroscopically verified grade III and IV patellar cartilage defects (defect group) were compared with a matched-pair control group of patients with isolated traumatic rupture of the anterior cruciate ligament without cartilage defects of the patellofemoral joint. Preoperative MRI images were analysed retrospectively with regard to patellar geometry (width, thickness, facet angle), trochlear geometry (dysplasia according to Dejour, sulcus angle, sulcus depth, lateral condyle index, trochlea facet asymmetry, lateral trochlea inclination) and patellofemoral alignment (tibial tuberosity-trochlear groove distance, patella height, lateral patella displacement, lateral patellofemoral angle, patella tilt, congruence angle). In addition to the comparison of group values, the measured values were compared to normal values reported in the literature, and the frequency of patients with pathologic findings was compared between both groups. The defect group demonstrated a significantly higher proximal chondral sulcus angle (p < 0.001), a significantly higher distal osseal sulcus angle (p = 0.004), a significantly lower distal sulcus depth (p = 0.047), a significantly lower lateral condyle index (p = 0.045), a significantly lower Caton-Deschamps index (p = 0.020) and a significantly higher Insall-Salvati index (p = 0.010). A major trochlear dysplasia (grade B-D) was significantly more common in the defect group (54 vs. 19%; p < 0.001). Eighty-eight per cent of patients in the defect group demonstrated at least one pathologic finding, compared to 63% in the control group (p = 0.006). Two or more pathologic findings were observed in 42% of the defect group and in 19% of the control group (p = 0.019). There was no significant correlation between the localization of the chondral defects and the results of the measured parameters. Cartilage defects of the patella are associated with the geometry of the patellofemoral joint. In particular, a flat and shallow trochlea, trochlea dysplasia and patella alta seem to contribute to the development of patellar cartilage defects, which must be taken into consideration when planning to do surgical cartilage repair at the patella. III.

The problem of chondromalacia patellae.

PubMed

Outerbridge, R E; Dunlop, J A

1975-01-01

Daily activity subjects the human patella to forces often several times the individual's body weight. Healthy cartilage can adjust to these forces if they are not too excessive, concentrated, or repetitive. Such abnormal stresses most frequently occur with the disturbance of normal patellar mechanical function. Chondromalacia patellae is the result common to a wide variety of unusual traumata. Treatment must be directed primarily not toward the damaged patellar cartilage but toward a correction of the mechanical abnormality causing it. Until proven otherwise, a young female complaining of knee joint pain, particularly if bilateral, should be considered as suffering from a subluxating patella, with or without chondromalacia patellae.

Chondroblastoma of the patella with aneurysmal bone cyst.

PubMed

Tan, Honglue; Yan, Mengning; Yue, Bing; Zeng, Yiming; Wang, You

2014-01-01

Chondroblastoma of the patella is rare. Aneurysmal bone cysts, which develop from a prior lesion such as a chondroblastoma, are seldom seen in the patella. The authors report a case of a 36-year-old man who presented with 2 years of right knee pain without calor, erythema, pain on palpation, or abnormal range of motion. Radiological studies suggested aneurysmal bone cyst. The lesion was excised with curettage and the residual cavity filled with autogenous bone graft. Histopathology revealed chondroblastoma associated with a secondary aneurysmal bone cyst. In the follow-up period, the patient demonstrated normal joint activities with no pain. Normal configuration of the patella and bone union were shown on plain radiographs. The authors present a review of the literature of all cases of patellar chondroblastoma with aneurysmal bone cyst. This case is the 14th report of aneurysmal bone cyst arising in a chondroblastoma of the patella. According to the literature, computed tomography and magnetic resonance imaging are useful in the study of these lesions. The pathologic diagnosis is based on the presence of chondroblastoma and aneurysmal bone cyst. Treatment of this lesion includes patellectomy, curettage alone, and curettage with bone grafting. Despite the risk of recurrence of this lesion in the patella, the authors first recommend curettage followed by filling the cavity with bone graft. To protect the anterior tension of the patella intraoperatively, the bone window should be made at the medial edge of the patella to perform the curettage and bone grafting.

Position of the patella in adults in central India: evaluation of the Insall-Salvati ratio.

PubMed

Upadhyay, Sachin; Raza, H K T; Srivastava, Pranay

2013-04-01

To assess the Insall-Salvati ratio in normal Indian adults to determine its applicability and the incidence of patella alta and baja in Indian populations. 800 knees in 200 men and 200 women aged 18 to 50 (mean, 30) years were evaluated using lateral radiographs. The knee was set in semi-flexion (30º) to enable good visualisation of the patellar tendon and its insertion into the tibia on radiographs. The length of the patellar tendon (LT) over the length of the patella (LP)-the Insall-Salvati ratio-was measured, using a vernier caliper. The mean LT/LP ratio was 1.14 (standard deviation, 0.18). Based on the 95% confidence interval, the ratio was considered normal if within ±40%. The LT/LP ratio was significantly higher in females than males (1.17 vs. 1.12, p<0.01). The cut-off point of patella alta was significantly greater in our Indian subjects than in western subjects (>1.5 vs. >1.2, p<0.0001). In the present cohort, the frequencies of patella alta (ratio, >1.5) and patella baja (ratio, <0.7) were 2.8% and 1%, respectively. The use of the Insall-Salvati ratio to determine the patellar position is less applicable to Indian populations in which squatting, sitting cross-legged, and kneeling are customs. We propose that the normal range of the ratio for squatters among Indian populations be 0.7 to 1.5.

Further delineation of the ear, patella, short stature syndrome (Meier-Gorlin syndrome).

PubMed

Boles, R G; Teebi, A S; Schwartz, D; Harper, J F

1994-07-01

Two daughters of phenotypically normal parents are described with severe proportional dwarfism with microcephaly, peculiar craniofacial anomalies, microtia, absent patellae, joint hyperextensibility, and other anomalies. Intrafamilial variability is minimal. This combination of anomalies has many similarities to the six cases previously described with the Ear, Patellae, Short stature syndrome (Meier-Gorlin syndrome), which is distinguished by the triad of microtia, absent patellae and growth retardation. Autosomal recessive inheritance is strongly suggested by the presence of two pairs of affected siblings and the equal sex ratio.

[Correlation analysis on the disorders of patella-femoral joint and torsional deformity of tibia].

PubMed

Sun, Zhen-Jie; Yuan, Yi; Liu, Rui-Bo

2015-03-01

To reveal the possible mechanism involved in patella-femoral degenerative arthritis (PFDA) in- duced by torsion-deformity of tibia via analyzing the relationship between torsion-deformity of the tibia in patients with PFDA and the disorder of patella-femoral joint under the static and dynamic conditions. From October 2009 to October 2010, 50 patients (86 knees, 24 knees of male patients and 62 knees of female patients) with PFDA were classified as disease group and 16 people (23 knees, 7 knees of males and 16 knees of females) in the control group. The follow indexes were measured: the torsion-angle of tibia on CT scanning imagings, the patella-femoral congruence angle and lateral patella-femoral angle under static and dynamic conditions when the knee bent at 30 degrees of flexion. Based on the measurement results, the relationship between the torsion-deformity of tibias and the disorders of patella-femoral joints in patients with PFDA were analyzed. Finally,the patients were divided into three groups including large torsion-angle group, small torsion-angle group and normal group according to the size of torsion-angle, in order to analyze the relationship between torsion-deformity and disorders of patella-femoral joint, especially under the dynamic conditions. Compared with patients without PFDA, the ones with PFDA had bigger torsion-angle (30.30 ± 7.11)° of tibia, larger patella-femoral congruence angle (13.20 ± 3.94)° and smaller lateral patella-femoral angle (12.30 ± 3.04)°. The congruence angle and lateral patella-femoral angle under static and dynamic conditions had statistical differences respectively in both too-big torsion-angle group and too-small torsion-angle group. The congruence angle and lateral patella-femoral angle under static and dynamic conditions had no statistical differences in normal torsion-angle group. Torsion-deformity of tibia is the main reason for disorder of patella-femoral joint in the patients with PFDA. Torsion-deformity of tibia is always accompanied by instability of patella-femoral joint,especially under the dynamic condition, thus causing PFDA. It can not only provide arrangement information and degenerative condition of patella-femoral joint,but also provide guidance through the analysis on the relationship for better clinical prevention and early treatment of degenerative bone and joint disease.

Unique patellofemoral alignment in a patient with a symptomatic bipartite patella.

PubMed

Ishikawa, Masakazu; Adachi, Nobuo; Deie, Masataka; Nakamae, Atsuo; Nakasa, Tomoyuki; Kamei, Goki; Takazawa, Kobun; Ochi, Mitsuo

2016-01-01

A symptomatic bipartite patella is rarely seen in athletic adolescents or young adults in daily clinical practice. To date, only a limited number of studies have focused on patellofemoral alignment. The current study revealed a unique patellofemoral alignment in a patient with a symptomatic bipartite patella. Twelve patients with 12 symptomatic bipartite patellae who underwent arthroscopic vastus lateralis release (VLR) were investigated (10 males and two females, age: 15.7±4.4years). The radiographic data of contralateral intact and affected knees were reviewed retrospectively. From the lateral- and skyline-view imaging, the following parameters were measured: the congruence angle (CA), the lateral patellofemoral angle (LPA), and the Caton-Deschamps index (CDI). As an additional parameter, the bipartite fragment angle (BFA) was evaluated against the main part of the patella in the skyline view. Compared with the contralateral side, the affected patellae were significantly medialized and laterally tilted (CA: P=0.019; LPA: P=0.016), although there was no significant difference in CDI (P=0.877). This patellar malalignment was found to significantly change after VLR (CA: P=0.001; LPA: P=0.003) and the patellar height was significantly lower than in the preoperative condition (P=0.016). In addition, the BFA significantly shifted to a higher degree after operation (P=0.001). Patients with symptomatic bipartite patellae presented significantly medialized and laterally tilted patellae compared with the contralateral intact side. This malalignment was corrected by VLR, and the alignment of the bipartite fragment was also significantly changed. Level IV, case series. Copyright © 2015 Elsevier B.V. All rights reserved.

Decreased torque and electromyographic activity in the extensor thigh muscles in chondromalacia patellae.

PubMed

Väätäinen, U; Airaksinen, O; Jaroma, H; Kiviranta, I

1995-01-01

The alterations in thigh muscle properties of chondromalacia patellae patients during isometric and dynamic endurance tests were studied using a variokinetic knee testing system linked to surface EMG. A total of 41 patients (chondromalacia group) with arthroscopically certified chondromalacia of the patella were studied. The control group consisted of 31 healthy adult volunteers with no history of knee pain or trauma. Peak torque values were 21% (p < 0.01) and force output values 25% (p < 0.05) lower on the symptomatic side of the chondromalacia group than in the control group. The decrease in the ratio between integrated EMG (IEMG) and measured force were found in all parts of the quadriceps femoris muscle in patients with chondromalacia of the patella in isometric extension. No change in the normalized IEMG levels of the thigh muscles were found between chondromalacia patients and controls in dynamic endurance test. The severity of the chondromalacia of the patella did not affect the level of electromyographic activation in thigh muscles. The ratio of normalized EMG levels of vastus medialis and vastus lateralis did not differ between the groups. The present study showed that chondromalacia patellae patients have reduced force and electromyographic activation levels of quadriceps femoris muscle. Especially, the explosive strength of the quadriceps femoris muscle is reduced.

Forensic Identification of Bipartite Patella Misdiagnosed as Patella Fracture.

PubMed

Ma, Jingyuan; Shi, Fang; Huang, Chongya; Gu, Shanzhi

2017-07-01

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. © 2017 American Academy of Forensic Sciences.

The Analysis of Risk Factors in No Thumb Test in Total Knee Arthroplasty

PubMed Central

Kim, Jee Hyoung; Ko, Dong Oh; Yoo, Chang Wook; Chun, Tae Hwan; Lee, Jung Soo

2011-01-01

Background We would like to analyze the risk factors of no thumb test among knee alignment tests during total knee arthroplasty surgery. Methods The 156 cases of total knee arthroplasty by an operator from October 2009 to April 2010 were analyzed according to preoperative indicators including body weight, height, degree of varus deformity, and patella subluxation and surgical indicators such as pre-osteotomy patella thickness, degree of patella degeneration, no thumb test which was evaluated after medial prepatella incision and before bone resection (1st test), no thumb test which was evaluated with corrective valgus stress (2nd test, J test), and the kind of prosthesis. We comparatively analyzed indicators affecting no thumb test (3rd test). Results There was no relation between age, sex, and body weight and no thumb test (3rd test). Patellar sulcus angle (p = 0.795), patellar congruence angle (p = 0.276) and preoperative mechanical axis showed no relationship. The 1st no thumb test (p = 0.007) and 2nd test (p = 0.002) showed significant relation with the 3rd no thumb test. Among surgical indicators, pre-osteotomy patella thickness (p = 0.275) and degeneration of patella (p = 0.320) were not relevant but post-osteotomy patellar thickness (p = 0.002) was relevant to no thumb test (3rd test). According to prosthesis, there was no significance with Nexgen (p = 0.575). However, there was significant correlation between Scorpio (p = 0.011), Vanguard (p = 0.049) and no thumb test (3rd test). Especially, Scorpio had a tendency to dislocate the patella, but Vanguard to stabilize the patella. Conclusions No thumb test (3rd test) is correlated positively with 1st test, 2nd test, and post-osteotomy patella thickness. Therefore, the more patella osteotomy and the prosthesis with high affinity to patellofemoral alignment would be required for correct patella alignment. PMID:22162789

Arthroscopy in the diagnosis of chondromalacia patellae.

PubMed Central

Leslie, I J; Bentley, G

1978-01-01

Chondromalacia patellae is difficult to diagnosis clinically with accuracy. In order to clarify the relevant symptoms and signs, 78 patients presenting with a clinical diagnosis of chondromalacia were examined by arthroscopy. In 49% of the knees no abnormalities were found. Presenting symptoms were similar in the normal and abnormal groups. Physical signs were more helpful in diagnosis and it is considered that the presence of an effusion, quadriceps wasting, and patello-femoral crepitus are the most important clinical findings in the diagnosis of chondromalacia patellae. The arthroscope is valuable instrument in establishing the diagnosis of chondromalacia patellae especially in the teenage female. Images PMID:749700

Increased incidence of patella baja after total knee arthroplasty revision for infection.

PubMed

Chen, Antonia F; Tetreault, Matthew W; Levicoff, Eric A; Fedorka, Catherine J; Rothenberg, Adam C; Klatt, Brian A

2014-12-01

The incidence of patella baja in total knee arthroplasty (TKA) revisions for aseptic and septic causes is not well defined. We retrospectively reviewed 101 mobile-bearing TKA revisions performed between 2003 and 2009. Aseptic (n=67) and septic (n=34) revisions were compared for patella baja. A nonarticulating spacer was used as the initial treatment for infected cases. The Insall-Salvati ratio was radiographically measured before surgery (preexplant for septic revisions) and at latest follow-up (postreplant for septic revisions). Mean (SD) Insall-Salvati ratio did not differ between groups before surgery, 1.00 (0.25) for aseptic and 0.96 (0.22) for septic, but differed significantly after surgery, 0.99 (0.23) for aseptic and 0.77 (0.24) for septic. After correcting for preoperative patellar height, there was a statistically significant postoperative difference between aseptic cases, 1.09 (0.19), and septic cases, 0.82 (0.21). There was also a significant difference in mean (SD) postoperative range of motion (ROM) between aseptic cases, 108.0° (20.7°), and septic cases, 92.2° (34.6°), and decreased ROM between cases with patella baja, 95.1° (31.6°) and cases without patella baja, 106.8° (23.6°). TKA revisions done for septic causes using a nonarticulating spacer resulted in a higher incidence of patella baja and decreased ROM.

The coupled effects of crouch gait and patella alta on tibiofemoral and patellofemoral cartilage loading in children.

PubMed

Brandon, Scott C E; Thelen, Darryl G; Smith, Colin R; Novacheck, Tom F; Schwartz, Michael H; Lenhart, Rachel L

2018-02-01

Elevated tibiofemoral and patellofemoral loading in children who exhibit crouch gait may contribute to skeletal deformities, pain, and cessation of walking ability. Surgical procedures used to treat crouch frequently correct knee extensor insufficiency by advancing the patella. However, there is little quantitative understanding of how the magnitudes of crouch and patellofemoral correction affect cartilage loading in gait. We used a computational musculoskeletal model to simulate the gait of twenty typically developing children and fifteen cerebral palsy patients who exhibited mild, moderate, and severe crouch. For each walking posture, we assessed the influence of patella alta and baja on tibiofemoral and patellofemoral cartilage contact. Tibiofemoral and patellofemoral contact pressures during the stance phase of normal gait averaged 2.2 and 1.0 MPa. Crouch gait increased pressure in both the tibofemoral (2.6-4.3 MPa) and patellofemoral (1.8-3.3 MPa) joints, while also shifting tibiofemoral contact to the posterior tibial plateau. For extended-knee postures, normal patellar positions (Insall-Salvatti ratio 0.8-1.2) concentrated contact on the middle third of the patellar cartilage. However, in flexed knee postures, both normal and baja patellar positions shifted pressure toward the superior edge of the patella. Moving the patella into alta restored pressure to the middle region of the patellar cartilage as crouch increased. This work illustrates the potential to dramatically reduce tibiofemoral and patellofemoral cartilage loading by surgically correcting crouch gait, and highlights the interaction between patella position and knee posture in modulating the location of patellar contact during functional activities. Copyright © 2017 Elsevier B.V. All rights reserved.

Is Selectively Not Resurfacing the Patella an Acceptable Practice in Primary Total Knee Arthroplasty?

PubMed

Maradit-Kremers, Hilal; Haque, Omar J; Kremers, Walter K; Berry, Daniel J; Lewallen, David G; Trousdale, Robert T; Sierra, Rafael J

2017-04-01

To resurface or not to resurface the patella remains a controversy in total knee arthroplasty (TKA). The purpose of this study was to assess the long-term outcomes associated with selectively not resurfacing the patella. This was a historical cohort study of 15,497 patients with 21,371 primary TKA procedures performed at a single institution between 1985 and 2010. The cohort included 402 (2%) knees with unresurfaced patellae and 20,969 knees with all-polyethylene patellae designs. Reasons for not resurfacing the patella were documented. Multivariable Cox regression analyses were used to estimate the risk of complications and revisions among procedures with unresurfaced patellae. According to the surgeon, reasons for not resurfacing were normal cartilage (226, 56%), young patient (30, 8%), thin patella (53, 13%), and surgeons' choice (93, 23%). In age, sex, and calendar year-adjusted analyses, the risk of complications (hazard ratio [HR]: 1.25, 95% confidence interval [CI]: 1.06, 1.46) and all-cause revisions (HR: 1.39, 95% CI: 1.02, 1.89) were significantly higher after TKA with unresurfaced patellae. However, after adjusting for femoral component types and operative diagnoses, these associations were no longer significant. The only group with significantly worse outcomes were those with a thin patellae with increased risk of complications (HR: 2.66, 95% CI: 1.70, 4.17) and revisions (HR: 5.94, 95% CI: 2.35, 15.02). Yet, the excess risk in the thin patellae group was mainly due to infections, and not related to unresurfaced patellae. Selectively not resurfacing the patella seemed to provide similar results compared with routine resurfacing. Copyright © 2016 Elsevier Inc. All rights reserved.

Quantitative analysis of the patella following the harvest of a quadriceps tendon autograft with a bone block.

PubMed

Ferrer, Gerald A; Miller, R Matthew; Murawski, Christopher D; Tashman, Scott; Irrgang, James J; Musahl, Volker; Fu, Freddie H; Debski, Richard E

2016-09-01

The objective of this study was to determine parameters associated with patellar fracture after quadriceps tendon autograft harvest. Thirteen non-fractured and five fractured patella surface models were created based on patient data obtained from a prospective randomized clinical trial in order to assess geometric parameters and bending stress. Measurements that describe the bone block harvest site geometry were used to calculate three normalized parameters. The relative depth parameter describes the thickness of the bone block harvest site with respect to the thickness of the patella at the harvest site. The asymmetry parameter defines the medial-lateral location of the bone bock harvest site. The normalized bending stress parameter assesses the bending stress experienced by the remaining bone beneath the bone block harvest site. The relative depth of the bone block harvest site in the non-fractured patellae was 27 ± 12 % and for the fractured patellae was 42 ± 14 % (p < 0.05). With a value <1 indicating a more lateral location of the harvest site, asymmetry for the non-fractured group was 1.0 ± 0.5 and 0.7 ± 0.4 for the fractured group (n.s.). The maximum bending stress experienced by the non-fractured patellae was (1.8 × 10(-3) ± 1.3 × 10(-3)) mm(-3) × M and for the fractured patellae was over three times greater (6.3 × 10(-3) ± 3.7 × 10(-3)) mm(-3) × M (p < 0.05). Based on the non-uniform geometry of the patella, an emphasis should be made on harvesting a standard percentage of patella thickness rather than a fixed depth. In order to minimize the incidence of a patellar fracture, bone blocks should not be taken laterally and should not exceed 30 % of the total patella thickness at the harvest site.

Short stature and hypothyroidism in a child with Nail-Patella Syndrome. A case report.

PubMed

Goecke, C; Mellado, C; García, C; García, H

2018-02-01

Nail-Patella syndrome (NPS) (OMIM: 161200) or hereditary onycho-osteodysplasia is an autosomal dominant disorder characterized by skeletal anomalies, nail dysplasia, renal and ocular abnor malities. The diagnosis is based on clinical and radiological findings and confirmed by the identification of a heterozygous pathogenic variant in the LMX1B gene. Management of these patients involves conti nuous follow-up and treatment ofthe orthopedical, ocular and renal problems that mayoccur. To describe a case of NPS with short stature and hypothyroidism, an association that has not been described in the literature. An eleven-year-old boy with a height of 130 cm (-2.01 Stan dard Deviations [SD]) was referred to the Endocrine Unit at the age of 2 years due to altered thyroid tests. At that time, dysplastic nails and disproportionate short stature were detected. Radiological abnormalities initially suggested a skeletal dysplasia. A primary hypothyroidism was confirmed, without anti-thyroid antibodies and with a normal thyroid ultrasound. Levothyroxine treatment was initiated. The diagnosis of NPS was confirmed by a genetic study with a single pathogenic variant in the LMX1B gene. His father presented a similar phenotype with normal stature. His bone age was equivalent to his chronological age. Laboratory screening for short stature and a GH stimulation test were normal. We present a child with proven NPS with short stature and hypothyroi dism. We did not find publications that described this triple association. It can't be ruled out that there could be a relationship between NPS and the thyroid alterations found in this patient.

[Spatial orientation of the facies patellaris femoris].

PubMed

Hassenpflug, J; Hiss, E; Blauth, W

1987-01-01

The present article reports on the geometrical conditions of the physiological movement of the patella. The geometrical shape of 18 femoral condyles and patella sliding areas was investigated in order to describe basic data for the design of endoprostheses. Surface and direction of the facies patellaris femoris were determined by means of radiographic, mechanical and optical measurements. The curvature of the deepest patella sliding groove proves a constant correlation with the dorsal condylar curvature. In the frontal plane the lowest points of the sliding area run with a dispersion of +/- 4 degrees to the vertical line related to the transverse tangent on the dorsal condylar surface. Considering deviations of leg alignment the measures come close to an angle of about 0 degrees. So the direction of the patella sliding groove differs from the normal valgus position of the distal femur. Therefore in artificial knee replacement a lateral tilt of the patella sliding groove should not be propagated as 'physiological'.

Closing wedge retrotubercular tibial osteotomy and TKA for posttraumatic osteoarthritis with angular deformity.

PubMed

Meehan, John P; Khadder, Mohammad A; Jamali, Amir A; Trauner, Kenneth B

2009-05-01

Posttraumatic osteoarthritis of the knee can be associated with angular deformities and alterations in the joint line as a result of the initial trauma and subsequent surgical procedures. These deformities can be characterized as extra-articular or intra-articular or can involve aspects of both. Conversion to total knee arthroplasty (TKA) may require either a staged or a simultaneous corrective osteotomy to restore the limb alignment and proper knee function. This article describes a closing wedge retrotubercular tibia osteotomy performed concurrently with TKA in an effort to correct an extra-articular varus deformity and to improve the patella tendon height in relation to the reconstructed joint line. A 57-year-old man previously treated for a Schatzker type 6 tibia plateau fracture presented with symptoms of arthritis pain and instability as a result of a varus thrust with weight bearing. Radiographs revealed posttraumatic osteoarthritis, a 35 degrees varus deformity, and patella infera. Maintaining the tibia tubercle continuity with the distal tibia allowed for correction of the varus deformity and improvement in the patella tendon height relative to the joint line. At 5-year follow-up, the patient had osteotomy healing, clinically neutral limb alignment, and improvement in joint line biomechanics with resolution of symptoms of pain and instability.

Stress analysis in patella by three-dimensional photoelasticity

NASA Astrophysics Data System (ADS)

Chen, Riqi; Zhang, Jianxing; Jiang, Kunsheng

1991-12-01

In this paper, stress distribution in patella was studied by 3-D photoelastic experiments and finite element calculations. The experimental conditions were in good agreement with that of body mechanics: (1) The ratios of m. quadriceps femoris force FQ to lig. patella force FP were 1.03 - 1.42. (2) The angles between FQ and FP were 8.4 degree(s) - 18.7 degree(s). (3) The ratio of modulus of elasticity for epoxy resin and silicon rubber matched that for patella and cartilage, i.e., 145:1. The principal stresses and their path line, normal stresses, and contact stresses between patella and ossis femoris were determined in various flexion angles (15 degree(s), 30 degree(s), 45 degree(s), 60 degree(s), 75 degree(s), 90 degree(s)). Two of the correlations were: (1) Maximum principal stress in the front of patella; (sigma) max equals 35.8Wexp(0.024(alpha) ) KPa. (2) Maximum contact stress between patella and ossis femoris; (sigma) max equals -(6.86 - 0.14(alpha) + 0.02(alpha) 2)W KPa where W was body weight subjected by a single foot. It was proved that the transverse break of patella resulted from the case that the principle stress in the front of patella exceeded ultimate tensile strength. And Tension Band Wiring (TBW) therapy conformed to the law of physiological stress field. A modified K-needles position in TBW therapy was suggested. These results are useful for further research of human patella mechanics and recovery therapy. No similar result has been found in American MEDLIN Data Bank.

Biomechanical Assessment of Patellar Advancement Procedures for Patella Alta.

PubMed

Seidl, Adam; Baldini, Todd; Krughoff, Kevin; Shapiro, Joshua A; Lindeque, Bennie; Rhodes, Jason; Carollo, James

2016-05-01

Crouch gait deformity is common in children with cerebral palsy and often is associated with patella alta. Patellar tendon advancement typically is used to correct patella alta and restore normal knee mechanics. The purpose of this study was to determine the mechanical strength of surgical constructs used for fixation during patellar advancement procedures. This study used a cadaveric model to determine which of 3 surgical techniques is biomechanically optimal for patellar tendon advancement in treating patella alta. Twenty-four human cadaveric knees (8 per group) were prepared using 1 of 3 different common surgical techniques: tibial tubercle osteotomy, patellar tendon partial resection and repair at the distal patella, and patellar tendon imbrication. The patella was loaded from 25 to 250 N at 1 Hz for 1000 cycles. A significant difference in patella displacement under cyclical loading was found between surgical techniques. Tibial tubercle osteotomy exhibited significantly less displacement under cyclical loading than distal patella excision and repair (P<.0001) or imbrication (P=.0088). Imbrication exhibited significantly less displacement than distal patella excision and repair (P=.0006). Tibial tubercle osteotomy survived longest. Based on failure criteria of 5 mm of displacement, tibial tubercle osteotomy lasted between 250 and 500 cycles. The other 2 techniques failed by 25 cycles. This study offers quantitative evidence regarding the relative mechanical strength of each construct and may influence choice of surgical technique. [Orthopedics. 2016; 39(3):e492-e497.]. Copyright 2016, SLACK Incorporated.

Proximalisation of the tibial tubercle gives a good outcome in patients undergoing revision total knee arthroplasty who have pseudo patella baja.

PubMed

Vandeputte, F-J; Vandenneucker, H

2017-07-01

The aim of this study was to compare the outcome of revision total knee arthroplasty (TKA) with and without proximalisation of the tibial tubercle in patients with a failed primary TKA who have pseudo patella baja. All revision TKAs, performed between January 2008 and November 2013 at a tertiary referral University Orthopaedic Department were retrospectively reviewed. Pseudo patella baja was defined using the modified Insall-Salvati and the Blackburne-Peel ratios. A proximalisation of the tibial tubercle was performed in 13 patients with pseudo patella baja who were matched with a control group of 13 patients for gender, age, height, weight, body mass index, length of surgery and Blackburne-Peel ratio. Outcome was assessed two years post-operatively using the Knee Society Score (KSS). The increase in KSS was significantly higher in the osteotomy group compared with the control group. The outcome was statistically better in patients in whom proximalisation of > 1 cm had been achieved compared with those in whom the proximalisation was < 1 cm. In this retrospective case-control study, a proximal transfer of the tibial tubercle at revision TKA in patients with pseudo patella baja gives good outcomes without major complications. Cite this article: Bone Joint J 2017;99-B:912-16. ©2017 The British Editorial Society of Bone & Joint Surgery.

Socioeconomic factors and individual lifestyles influencing the incidence of patella fractures: a national population-based survey in China.

PubMed

Zhu, Yanbin; Liu, Song; Chen, Wei; Wang, Lin; Zhang, Xiaolin; Zhang, Yingze

2018-05-19

We aimed to do a national survey on the population-based incidence of patella fractures and related risk factors fracture in China. All the data on patella fractures were available from the China National Fracture Survey (CNFS) between January and May in 2015. And in the CNFS, all eligible household members were selected from 24 urban cities and 24 rural counties of eight provinces of China, with stratified random sampling and the probability proportional to size method used. Questionnaire was sent to every participant for data collection and quality control was accomplished by our research team members. A total of 512,187 valid questionnaires were collected, and relevant data were abstracted. There were a total of 69 patients with 69 patella fractures that occurred in 2014, indicating that the incidence was 13.5 (95% CI, 10.3-16.7))/100,000 person-years. Slip, trip, or fall from standing height was the most common cause, leading to 69.6% (48/69) of patella factures, followed by traffic accidents (18.8%, 13/69). Home and road were the first two most common places, where 86.9% of the overall injuries occurred. Age of 45-64 and 65-74 years, alcohol consumption and previous history of fractures were identified as independent risk factors for patella fracture. Specific public health policies focusing on decreasing alcohol consumption should be implemented. Individuals aged 45-64 and 65-74 should pay more attention to bone mass density and prevention of falls, especially those with previous history of fracture.

Hardness of the subchondral bone of the patella in the normal state, in chondromalacia, and in osteoarthrosis.

PubMed

Björkström, S; Goldie, I F

1982-06-01

The hardness of bone is its property of withstanding the impact of a penetrating agent. It has been found that articular degenerative changes in, for example, the tibia (knee) are combined with a decrease in the hardness of the subchondral bone. In this investigation the hardness of subchondral bone in chondromalacia and osteoarthrosis of the patella has been analysed and compared with normal subchondral bone. Using an indentation method originally described by Brinell the hardness of the subchondral bone was evaluated in 7 normal patellae, in 20 with chondromalacia and in 33 with osteoarthrosis. A microscopic and microradiographic study of the subchondral bone was carried out simultaneously. Hardness was lowest in the normal material. The mean hardness value beneath the degenerated cartilage differed only slightly from that of the normal material, but the variation of values was increased. The hardness in bone in the chondromalacia area was lower than the hardness in bone covered by surrounding normal cartilage. The mean hardness value in bone beneath normal parts of cartilage in specimens with chondromalacia was higher than the mean hardness value of the normal material. In the microscopic and microradiographic examination it became evident that there was a relationship between trabecular structure and subchondral bone hardness; high values: coarse and solid structure; low values: slender and less regular structure.

[In vitro analysis of the continuous active patellofemoral kinematics of the normal and prosthetic knee].

PubMed

Jenny, J-Y; Lefèbvre, Y; Vernizeau, M; Lavaste, F; Skalli, W

2002-12-01

In vitro experiments are particularly useful for studying kinematic changes from the normal knee to experimental conditions simulating different disease states. We developed an experimental protocol allowing a kinematic analysis of the femorotibial and femoropatellar joints in the healthy knee and after implantation of a knee prosthesis, according to the central pivot during simulated active loaded movement from the standing to sitting position. An experimental device was designed to apply force to the femur of a cadaveric specimen including the femur, the patella and the tibia. The tibia was angled in the sagittal plane and the femur was free to move in space in response to the geometric movement of the knee joint, the capsuloligamentary structures, the quadriceps tendon and gravity. Variation in the length of the quadriceps tendon controlled the flexion-extension movement. The experimental setup included computer-controlled activation allowing continuous coordinated movement of the femur relative to the tibia and of the tibia relative to the ground. Standard activations simulated movement from the standing to the sitting position. Five pairs of fresh-frozen cadaver specimens including the entire femur, patella, tibia and fibula, the capsuloligamentary and intra-articular structures of the knee, the superior and inferior tibiofibular ligaments and the quadriceps tendon were studied. The quadriceps tendon was connected to the computer-guided activation device. Reflectors were fixed onto the anterior aspect of the femur, the superior tibial epiphysis and the center of the patella. Anatomic landmarks on the femur, the tibia, and the patella were identified to determine the plane of movement of each bone in the three rotation axes and the three translation directions. Three infrared cameras recorded movements of the reflectors fixed on the bony segments and, by mathematical transformation, the movement of the corresponding bony segment, displayed in time-course curves. The patella moved in continuous fashion over the femur, directly following the angle of knee flexion with a ratio of about 60%, which was constant for all knees studied and for all configurations. The patella of healthy knees and knees implanted with a unicompartmental prosthesis exhibited medial rotation during the first 30 degrees of flexion, with a movement of about of 10 degrees, then a lateral rotation of about 10 degrees to 20 degrees when the flexion reached 90 degrees; implantation of a total knee prosthesis led to a medial rotation which was continuous from 5 degrees to 15 degrees. There was a trend towards continuous abduction of about 10 degrees. The patella exhibited a continuous anterior translation of 10 to 20 mm from the tibia with increasing knee flexion, in both normal and prosthetic knees (unicompartmental prosthesis); knees implanted with a total knee prosthesis exhibited 5 to 10 mm anterior translation from 0 degrees to 50 degrees flexion, then an equivalent posterior translation for 50 degrees to 90 degrees flexion. The patella made a continuous 5 to 10 mm medial translation movement over the tibia in both normal and prosthetic (unicompartmental) knees; knees implanted with a total knee prosthesis exhibited 0 to 5 mm lateral translation starting after 50 degrees flexion. The patella also exhibited a continuous distal translation over the tibia of about 20 to 30 mm, for all configurations. The experimental set up enables a comparison of the kinetics of a normal knee with the kinetics observed after implantation of a prosthesis on the same knee. Implantation of a unicompartmental medial prosthesis, leaving the posterior cruciate ligament intact and irrespective of the status of the anterior cruciate ligament, did not, in these experimental conditions, exhibit any significant difference in the femorotibial or femoropatellar kinetics compared with the same normal knee. Implantation of a total knee prosthesis had a significant effect on the femoropatellar kinematics, compared with the same knee before implantation. The main anomalies were related to the medial-lateral rotation of the patella which exhibited an abnormal lateral rotation, possibly favorable for subluxation; these changes were directly related to femorotibial rotation after implantation of the total prosthesis and appeared to be related to the symmetry of the femoral condyles of the prosthesis model studied, perturbing the normal automatic rotation of the knee. There is thus a strong relationship between femorotibial and femoropatellar kinetics in the total knee prosthesis.

Chondrosarcoma of the patella: A case report.

PubMed

Ye, Conglin; Luo, Zhiping; Zeng, Jin; Dai, Min

2017-09-01

Chondrosarcoma, characterized by the production of cartilage matrix, is a common bone tumor, accounting for 20% to 27% of all malignant bone tumors. It often occurs in the cartilage of the pelvis, femur, tibia, and humerus. However, chondrosarcoma of the patella is extremely rare. The present study describes a case of chondrosarcoma affecting the right patella in a 68-year-old woman. The chief complaints were painful swelling and limitation of motion of the right knee for about half a year. The pain was a kind of dull ache. The skin around the right knee was red and hot. Moreover, she had a claudication gait due to the symptoms. Irregular lytic lesions with ill-defined margins in the patella were determined through computed tomography and magnetic resonance imaging. The diagnosis of primary grade II chondrosarcoma was finally confirmed on the basis of postoperative pathological examination. The patient underwent an open surgery named extensive resection of patellar tumor to remove the tumor tissue completely. The patient was discharged without any complications 1 week after the surgery. At the 3-month follow-up, the patient was completely free from pain during daily activities, and normal range of motion of the right knee was achieved. Her gait was normal. There was no evidence of recurrence. We believe that an extensive resection is suitable for treating chondrosarcoma to avoid as far as possible local recurrence. An awareness of the potential for chondrosarcoma to present in the patella is crucial for both orthopedic surgeons and radiologists when confronted with similar cases. Besides, as reports of chondrosarcoma of the patella are rare, this study adds a better understanding of this rare condition to the medical literature.

Chondromalacia patellae: diagnosis with MR imaging.

PubMed

McCauley, T R; Kier, R; Lynch, K J; Jokl, P

1992-01-01

Most previous studies of MR imaging for detection of chondromalacia have used T1-weighted images. We correlated findings on axial MR images of the knee with arthroscopic findings to determine MR findings of chondromalacia patellae on T2-weighted and proton density-weighted images. The study population included 52 patients who had MR examination of the knee with a 1.5-T unit and subsequent arthroscopy, which documented chondromalacia patellae in 29 patients and normal cartilage in 23. The patellar cartilage was assessed retrospectively for MR signal and contour characteristics. MR diagnosis based on the criteria of focal signal or focal contour abnormality on either the T2-weighted or proton density-weighted images yielded the highest correlation with the arthroscopic diagnosis of chondromalacia. When these criteria were used, patients with chondromalacia were detected with 86% sensitivity, 74% specificity, and 81% accuracy. MR diagnosis based on T2-weighted images alone was more sensitive and accurate than was diagnosis based on proton density-weighted images alone. In conclusion, most patients with chondromalacia patellae have focal signal or focal contour defects in the patellar cartilage on T2-weighted MR images. These findings are absent in most patients with arthroscopically normal cartilage.

Chondromalacia patellae: fat-suppressed MR imaging.

PubMed

Rose, P M; Demlow, T A; Szumowski, J; Quinn, S F

1994-11-01

To evaluate the accuracy of fat-suppressed magnetic resonance (MR) imaging in diagnosing chondromalacia patellae. Seventy-one patients underwent fat-suppressed MR imaging and arthroscopy of the patellofemoral compartment. Findings were classified as early or advanced chondromalacia or as normal and were correlated with arthroscopic findings. Early and advanced stages of chondromalacia patellae were reliably detected, with positive predictive values of 85% and 92%, respectively. Specificity in early stages was 94% and in late stages was 98%. However, the overall accuracies did not differ substantially from those reported in studies that did not use fat-suppressed imaging. Axial, fat-suppressed MR imaging accurately depicts changes caused by chondromalacia patellae. Early stages can be seen as intrasubstance changes of increased signal intensity. Results of this study suggest a high degree of specificity in excluding both early and advanced changes.

Correlation between subcutaneous knee fat thickness and chondromalacia patellae on magnetic resonance imaging of the knee.

PubMed

Kok, Hong Kuan; Donnellan, John; Ryan, Davinia; Torreggiani, William C

2013-08-01

Chondromalacia patellae is a common cause of anterior knee pain in young patients and can be detected noninvasively with magnetic resonance imaging (MRI). The purpose of our study was to evaluate the correlation between subcutaneous fat thickness around the knee joint on axial MRIs as a surrogate marker of obesity, with the presence or absence of chondromalacia patellae. A retrospective review was conducted of knee MRIs in 170 patients who satisfied the inclusion criteria. Imaging was performed over a 12-month period on a 1.5T MRI system with a dedicated extremity coil. Two radiologists experienced in musculoskeletal imaging assessed each examination in consensus for the presence or absence of chondromalacia patellae and graded positive studies from 0 (absent) to 3 (full cartilage thickness defect). Measurement of subcutaneous knee fat thickness was obtained on the medial aspect of the knee. MRI findings of chondromalacia patellae were present in 33 patients (19.4%), of which, there were 11 grade 1 lesions (33.3%), 9 grade 2 lesions (27.3%), and 13 grade 3 lesions (39.4%). The mean subcutaneous knee fat thickness was significantly higher in the chondromalacia patellae group for all grades compared with the normal group (P < .001), and there was a significant correlation between subcutaneous knee fat thickness and grades of chondromalacia patellae (R = 0.48 [95% confidence interval, 0.38-0.68]; P < .001). Female patients had thicker subcutaneous knee fat and more severe grades of chondromalacia patellae. Subcutaneous knee fat thickness as a surrogate marker of obesity was positively associated with the presence and severity of chondromalacia patellae on MRI. Copyright © 2013 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

Evaluation of the relationship between T1ρ and T2 values and patella cartilage degeneration in patients of the same age group.

PubMed

Nishioka, Hiroaki; Hirose, Jun; Okamoto, Nobukazu; Okada, Tatsuya; Oka, Kiyoshi; Taniwaki, Takuya; Nakamura, Eiichi; Yamashita, Yasuyuki; Mizuta, Hiroshi

2015-03-01

The aim of this study was to investigate the association between the T1ρ and T2 values and the progression of cartilage degeneration in patients of the same age group. Sagittal T1ρ and T2 mapping and three-dimensional (3D) gradient-echo images were obtained from 78 subjects with medial knee osteoarthritis (OA). The degree of patella cartilage degeneration was classified into four groups using MRI-based grading: apparently normal cartilage, mild OA, moderate OA, and severe OA group. We measured the T1ρ and T2 values (ms) in the regions of interest set on the full-thickness patella cartilage. Then, we analyzed the relationship between the T1ρ and T2 values and the degree of patella cartilage degeneration. There were no significant differences in age among the four groups. Both the T1ρ and T2 values showed a positive correlation with the degree of OA progression (ρ=0.737 and ρ=0.632, respectively). By comparison between the apparently normal cartilage and the mild OA groups, there were significant differences in the T1ρ mapping, but not in the T2 mapping. Our study confirmed that T1ρ and T2 mapping can quantitatively evaluate the degree of patella cartilage degeneration in patients within the same age group. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Minimal effect of patella eversion on ligament balancing in cruciate-retaining total knee arthroplasty.

PubMed

Aunan, Eirik; Kibsgård, Thomas; Röhrl, Stephan M

2017-03-01

The effect of patellar eversion on ligament laxity measurements is still unclear. The purpose of this study was to investigate the influence of patellar eversion on medial and lateral ligament laxity measurements performed intra-operatively in total knee arthroplasty (TKA). A total of 49 knees (27 female) with mean age 70 years (42-83) and mean body mass index of 28.5 were operated consecutively with a cruciate-retaining prosthesis. Medial and lateral ligament laxity in extension and in 90° of flexion was measured with the spatula-method intra-operatively after implantation of the prosthetic components with the patella everted and thereafter with the patella repositioned. The corresponding changes in gap height and inclination were calculated. A statistically significant increase of 0.6 mm (p < 0.001) in ligament laxity (condylar lift-off) laterally in flexion was found with the patella repositioned compared to everted. No differences were found in extension or medially in flexion. Correspondingly, the flexion gap increased by 0.4 mm (p < 0.001) and the flexion gap inclination increased by 0.6° (p = 0.002) when the patella was repositioned. Earlier research has shown that ligament laxity must be at least 1-2 mm to cause inferior function after TKA. In the current study, we found that the effect of patellar eversion on ligament laxity measurements is too small to be considered clinically relevant. PROSPECTIVE STUDY EVALUATING THE EFFECT OF PATIENT CHARACTERISTICS: Level II.

Collagen crosslinks in chondromalacia of the patella.

PubMed

Väätäinen, U; Kiviranta, I; Jaroma, H; Arokosi, J; Tammi, M; Kovanen, V

1998-02-01

The aim of the study was to determine collagen concentration and collagen crosslinks in cartilage samples from chondromalacia of the patella. To study the extracellular matrix alterations associated to chondromalacia, we determined the concentration of collagen (hydroxyproline) and its hydroxylysylpyridinoline and lysylpyridinoline crosslinks from chondromalacia foci of the patellae in 12 patients and 7 controls from apparently normal cadavers. The structure of the collagen network in 8 samples of grades II-IV chondromalacia was examined under polarized light microscopy. The full-thickness cartilage samples taken with a surgical knife from chondromalacia lesions did not show changes in collagen, hydroxylysylpyridinoline and lysylpyridinoline concentration as compared with the controls. Polarized light microscopy showed decreased birefringence in the superficial cartilage of chondromalacia lesions, indicating disorganization or disappearance of collagen fibers in this zone. It is concluded that the collagen network shows gradual disorganization with the severity of chondromalacia lesion of the patella without changes in the concentration or crosslinks of collagen.

Isolated patellofemoral arthroplasty reproduces natural patellofemoral joint kinematics when the patella is resurfaced.

PubMed

Vandenneucker, Hilde; Labey, Luc; Vander Sloten, Jos; Desloovere, Kaat; Bellemans, Johan

2016-11-01

The objectives of this in vitro project were to compare the dynamic three-dimensional patellofemoral kinematics, contact forces, contact areas and contact pressures of a contemporary patellofemoral prosthetic implant with those of the native knee and to measure the influence of patellar resurfacing and patellar thickness. The hypothesis was that these designs are capable to reproduce the natural kinematics but result in higher contact pressures. Six fresh-frozen specimens were tested on a custom-made mechanical knee rig before and after prosthetic trochlear resurfacing, without and with patellar resurfacing in three different patellar thicknesses. Full three-dimensional kinematics were analysed during three different motor tasks, using infrared motion capture cameras and retroflective markers. Patellar contact characteristics were registered using a pressure measuring device. The patellofemoral kinematic behaviour of the patellofemoral arthroplasty was similar to that of the normal knee when the patella was resurfaced, showing only significant (p < 0.0001) changes in patellar flexion. Without patellar resurfacing, significant more patellar flexion, lateral tilt and lateral rotation was noticed. Compared to the normal knee, contact pressures were significantly elevated after isolated trochlear resurfacing. However, the values were more than doubled after patellar resurfacing. Changes in patellar thickness only influenced the antero-posterior patellar position. There was no other influence on the kinematics, and only a limited influence on the contact pressures in the low flexion angles. The investigated design reproduced the normal patellofemoral kinematics acceptable well when the patella was resurfaced. From a kinematic point of view, patellar resurfacing may be advisable. However, the substantially elevated patellar contact pressures remain a point of concern in the decision whether or not to resurface the patella. This study therefore not only adds a new point in the discussion whether or not to resurface the patella, but also supports the claimed advantage that a patellofemoral arthroplasty is capable to reproduce the natural knee kinematics.

Semitendinosus Tendon Transfer Associated With Distal Alignment for Patella Alta in a Patient With Recurrent Dislocations.

PubMed

Calderazzi, Filippo; Pellegrini, Andrea; Coviello, Gianluca; Groppi, Giulia; Ceccarelli, Francesco

2015-10-01

Patellofemoral instability is characterized by pain during normal daily activities and frequent dislocation events. In the reported case, an adolescent girl, aged 15 years, affected by left patellofemoral instability, underwent surgery with a double technique comprising tibial tubercle distalization and medial patellofemoral ligament reconstruction. In case of patella alta associated with patellofemoral instability, surgical treatment should focus on medial patellofemoral ligament repair and on recurrent instability prevention.

Femur rotation and patellofemoral joint kinematics: a weight-bearing magnetic resonance imaging analysis.

PubMed

Souza, Richard B; Draper, Christie E; Fredericson, Michael; Powers, Christopher M

2010-05-01

Controlled laboratory study using a cross-sectional design. To compare patellofemoral joint kinematics, femoral rotation, and patella rotation between females with patellofemoral pain (PFP) and pain-free controls using weight-bearing kinematic magnetic resonance imaging. Recently, it has been recognized that patellofemoral malalignment may be the result of femoral motion as opposed to patella motion. Fifteen females with PFP and 15 pain-free females between the ages of 18 and 45 years participated in this study. Kinematic imaging of the patellofemoral joint was performed using a vertically open magnetic resonance imaging system. Axial-oblique images were obtained using a fast gradient-echo pulse sequence. Images were acquired at a rate of 1 image per second while subjects performed a single-limb squat. Measures of femur and patella rotation (relative to the image field of view), lateral patella tilt, and lateral patella displacement were made from images obtained at 45 degrees , 30 degrees , 15 degrees , and 0 degrees of knee flexion. Group differences were assessed using a mixed-model analysis of variance with repeated measures. When compared to the control group, females with PFP demonstrated significantly greater lateral patella displacement at all angles evaluated and significantly greater lateral patella tilt at 30 degrees , 15 degrees , and 0 degrees of knee flexion. Similarly, greater medial femoral rotation was observed in the PFP group at 45 degrees , 15 degrees , and 0 degrees of knee flexion when compared to the control group. No group differences in patella rotation were found. Altered patellofemoral joint kinematics in females with PFP appears to be related to excessive medial femoral rotation, as opposed to lateral patella rotation. Our results suggest that the control of femur rotation may be important in restoring normal patellofemoral joint kinematics. J Orthop Sports Phys Ther 2010;40(5):277-285, Epub 12 March 2010. doi:10.2519/jospt.2010.3215.

The Relationship between Chondromalacia Patella, Medial Meniscal Tear and Medial Periarticular Bursitis in Patients with Osteoarthritis.

PubMed

Resorlu, Mustafa; Doner, Davut; Karatag, Ozan; Toprak, Canan Akgun

2017-12-01

This study investigated the presence of bursitis in the medial compartment of the knee (pes anserine, semimembranosus-tibial collateral ligament, and medial collateral ligament bursa) in osteoarthritis, chondromalacia patella and medial meniscal tears. Radiological findings of 100 patients undergoing magnetic resonance imaging with a preliminary diagnosis of knee pain were retrospectively evaluated by two radiologists. The first radiologist assessed all patients in terms of osteoarthritis, chondromalacia patella and medial meniscal tear. The second radiologist was blinded to these results and assessed the presence of bursitis in all patients. Mild osteoarthritis (grade I and II) was determined in 55 patients and severe osteoarthritis (grade III and IV) in 45 cases. At retropatellar cartilage evaluation, 25 patients were assessed as normal, while 29 patients were diagnosed with mild chondromalacia patella (grade I and II) and 46 with severe chondromalacia patella (grade III and IV). Medial meniscus tear was determined in 51 patients. Severe osteoarthritis and chondromalacia patella were positively correlated with meniscal tear (p < 0.001 and p = 0.018, respectively). Significant correlation was observed between medial meniscal tear and bursitis in the medial compartment (p = 0.038). Presence of medial periarticular bursitis was positively correlated with severity of osteoarthritis but exhibited no correlation with chondromalacia patella (p = 0.023 and p = 0.479, respectively). Evaluation of lateral compartment bursae revealed lateral collateral ligament bursitis in 2 patients and iliotibial bursitis in 5 patients. We observed a greater prevalence of bursitis in the medial compartment of the knee in patients with severe osteoarthritis and medial meniscus tear.

The lumbar facet arthrosis syndrome. Clinical presentation and articular surface changes.

PubMed

Eisenstein, S M; Parry, C R

1987-01-01

We describe a lumbar facet syndrome in which disabling symptoms are associated with normal or near-normal plain radiographs. Local spinal fusion relieved symptoms in 12 patients; the excised facet joint surfaces showed some of the histological changes seen in chondromalacia patellae and in osteoarthritis of other large joints. The most frequent change was focal full-thickness cartilage necrosis or loss of cartilage with exposure of subchondral bone, but osteophyte formation was remarkably absent in all specimens. We suggest that there are both clinical and histological similarities between the facet arthrosis syndrome and chondromalacia patellae. Facet arthrosis may be a relatively important cause of intractable back pain in young and middle-aged adults.

[The clinical value of cartilaginous surface and corresponding osseous contour of patellofemoral joint].

PubMed

Zhang, Jian-Bing; Chen, Bai-Cheng; Zhang, Jing; Wang, Zhi-Qiang; Yan, Chang-Bao

2010-11-15

to investigate if the cartilaginous surface and corresponding osseous contour of the patellofemoral joint match in the axial plane for providing theoretical basis with evaluating alignment of patellofemoral joint and designing the part of patellofemoral joint in knee prosthesis. from January 2009 to March 2010, 9 human cadaver knees were prepared, which chandra of patellofemoral joint didn't degenerate. Each specimen was sectioned in the axial plane at 20° to 30° knee flax. The cross-sections revealed characteristics in the bony anatomy and corresponding articular surface geometry of the patellofemoral joint in the axial plane. Evaluating parameters included osseous patella congruence angle (OPCA), chondral patella congruence angle (CPCA), patella chondral convex point parameter (PCCPP), patella subchondral osseous convex point parameter (PSOCPP), the parameters of the deepest (chondral or osseous) point of the intercondylar sulcus. After that, the osseous and cartilaginous contours and subchondral osseous contours of the patella in the axial plane were analyzed through MRI data of 11 patients who didn't degenerate in patellofemoral joint cartilage. Parameters as same as cadaver knees were compared. data from specimens of OPCA was (-4.5 ± 1.1)°, CPCA was (0.5 ± 0.8)°, PCCPP was 1.13 ± 0.11, PSOCPP was 1.67 ± 0.14, PCDPIS was 1.35 ± 0.28, PODPIS was 1.38 ± 0.33. Date from MRI of OPCA was (-3.8 ± 1.4)°, CPCA was (0.7 ± 1.0)°, PCCPP was 1.05 ± 0.21, PSOCPP was 1.73 ± 0.18, PCDPIS was 1.41 ± 0.21, PODPIS was 1.37 ± 0.27. The patella exhibited significant differences in the bony vs. chondral anatomy (P < 0.05), but the intercondylar sulcus nearly match in the bony vs. chondral anatomy. the cartilaginous surface and corresponding osseous contour of the patella don't match in the patellofemoral joint axial plane, but that of the trochlea nearly matches. This is very important for accurately evaluating alignment of patellofemoral joint because the normal osseous alignment of patellofemoral joint don't represent the normal alignment and helpful for designing the part of patellofemoral joint in knee prosthesis.

Radiologically hyperdense zones of the patella seem to be partial osteonecroses subsequent to fracture treatment.

PubMed

Schüttrumpf, Jan Philipp; Behzadi, Cyrus; Balcarek, Peter; Walde, Tim Alexander; Frosch, Stephan; Wachowski, Martin Michael; Stürmer, Klaus Michael; Frosch, Karl-Heinz

2013-10-01

The blood supply to the proximal patella is provided primarily via intraosseous vessels from the inferior patella. Two vascular systems within the patella are distinguished: Tiny arteries penetrate the middle third of the anterior patellar surface via vascular foramina and continue in a proximal direction. Additional vessels enter the patella at its distal pole, between the patellar ligament and the articular surface, and also run proximally. As a result of the double vascular supply to the distal portion and the vulnerable blood supply to the proximal part, localized osteonecroses subsequent to fracture may occur within the patella and nearly exclusively affect the upper portion of the patella. Such focal regions of osteonecrosis may appear radiographically as localized regions of hyperdensity within the patella. The aim of this study was to investigate the extent to which radiologically hyperdense areas, possibly representing localized osteonecrosis, may occur subsequent to surgical treatment of a patella fracture and the influence that they have on the outcome of the fracture. Retrospective analysis of 100 patients who had been treated operatively for a patella fracture from January 1998 to December 2008 was conducted. The subjective pain rating, clinical scores, and patient satisfaction scores were recorded. Existing X-rays were assessed with regard to possible increased radiological dense areas. After an average of 60.61 ( ± 33.88) months, it was possible to perform a clinical follow-up on 60 patients aged 45.48 ( ± 18.51) years. Radiographic follow-up of all patients revealed that nine patients (9%) exhibited a hyperdense area in the proximal patella portion. X-rays showed radiopaque areas between 1 and 2 months after surgery. In seven cases, the radiological finding disappeared after six months. In two patients with persisting radiologically dense areas, bone necrosis was verified by means of magnetic resonance imaging (MRI) examination and a histological assessment, respectively. The clinical outcome of these patients with a hyperdense area on the patella, in this small series, was not shown to be worse than those who demonstrated normal healing. Radiologically hyperdense areas subsequent to patella fracture may represent partial osteonecrosis caused by localized vascular compromise. This was confirmed by MRI and histological examinations in two patients with persistent hyperdense lesions. The clinical outcome of patients with hyperdense zones seems to be poorer than that of patients without such findings, but no statistical difference was shown in this small series. It is possible that earlier surgical treatment and thus a shorter ischemic period as well as tissue-conserving operative techniques could prevent the occurrence of partial necroses. This hypothesis would require further study. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

The Relationship between Chondromalacia Patella, Medial Meniscal Tear and Medial Periarticular Bursitis in Patients with Osteoarthritis

PubMed Central

Doner, Davut; Karatag, Ozan; Toprak, Canan Akgun

2017-01-01

Abstract Background This study investigated the presence of bursitis in the medial compartment of the knee (pes anserine, semimembranosus-tibial collateral ligament, and medial collateral ligament bursa) in osteoarthritis, chondromalacia patella and medial meniscal tears. Patients and methods Radiological findings of 100 patients undergoing magnetic resonance imaging with a preliminary diagnosis of knee pain were retrospectively evaluated by two radiologists. The first radiologist assessed all patients in terms of osteoarthritis, chondromalacia patella and medial meniscal tear. The second radiologist was blinded to these results and assessed the presence of bursitis in all patients. Results Mild osteoarthritis (grade I and II) was determined in 55 patients and severe osteoarthritis (grade III and IV) in 45 cases. At retropatellar cartilage evaluation, 25 patients were assessed as normal, while 29 patients were diagnosed with mild chondromalacia patella (grade I and II) and 46 with severe chondromalacia patella (grade III and IV). Medial meniscus tear was determined in 51 patients. Severe osteoarthritis and chondromalacia patella were positively correlated with meniscal tear (p < 0.001 and p = 0.018, respectively). Significant correlation was observed between medial meniscal tear and bursitis in the medial compartment (p = 0.038). Presence of medial periarticular bursitis was positively correlated with severity of osteoarthritis but exhibited no correlation with chondromalacia patella (p = 0.023 and p = 0.479, respectively). Evaluation of lateral compartment bursae revealed lateral collateral ligament bursitis in 2 patients and iliotibial bursitis in 5 patients. Conclusions We observed a greater prevalence of bursitis in the medial compartment of the knee in patients with severe osteoarthritis and medial meniscus tear. PMID:29333118

Automatic anatomical structures location based on dynamic shape measurement

NASA Astrophysics Data System (ADS)

Witkowski, Marcin; Rapp, Walter; Sitnik, Robert; Kujawinska, Malgorzata; Vander Sloten, Jos; Haex, Bart; Bogaert, Nico; Heitmann, Kjell

2005-09-01

New image processing methods and active photonics apparatus have made possible the development of relatively inexpensive optical systems for complex shape and object measurements. We present dynamic 360° scanning method for analysis of human lower body biomechanics, with an emphasis on the analysis of the knee joint. The anatomical structure (of high medical interest) that is possible to scan and analyze, is patella. Tracking of patella position and orientation under dynamic conditions may lead to detect pathological patella movements and help in knee joint disease diagnosis. The processed data is obtained from a dynamic laser triangulation surface measurement system, able to capture slow to normal movements with a scan frequency between 15 and 30 Hz. These frequency rates are enough to capture controlled movements used e.g. for medical examination purposes. The purpose of the work presented is to develop surface analysis methods that may be used as support of diagnosis of motoric abilities of lower limbs. The paper presents algorithms used to process acquired lower limbs surface data in order to find the position and orientation of patella. The algorithms implemented include input data preparation, curvature description methods, knee region discrimination and patella assumed position/orientation calculation. Additionally, a method of 4D (3D + time) medical data visualization is proposed. Also some exemplary results are presented.

Reliability of clinical findings and magnetic resonance imaging for the diagnosis of chondromalacia patellae.

PubMed

Pihlajamäki, Harri K; Kuikka, Paavo-Ilari; Leppänen, Vesa-Veikko; Kiuru, Martti J; Mattila, Ville M

2010-04-01

This diagnostic study was performed to determine the correlation between anterior knee pain and chondromalacia patellae and to define the reliability of magnetic resonance imaging for the diagnosis of chondromalacia patellae. Fifty-six young adults (median age, 19.5 years) with anterior knee pain had magnetic resonance imaging of the knee followed by arthroscopy. The patellar chondral lesions identified by magnetic resonance imaging were compared with the arthroscopic findings. Arthroscopy confirmed the presence of chondromalacia patellae in twenty-five (45%) of the fifty-six knees, a synovial plica in twenty-five knees, a meniscal tear in four knees, and a femorotibial chondral lesion in four knees; normal anatomy was seen in six knees. No association was found between the severity of the chondromalacia patellae seen at arthroscopy and the clinical symptoms of anterior knee pain syndrome (p = 0.83). The positive predictive value for the ability of 1.0-T magnetic resonance imaging to detect chondromalacia patellae was 75% (95% confidence interval, 53% to 89%), the negative predictive value was 72% (95% confidence interval, 56% to 84%), the sensitivity was 60% (95% confidence interval, 41% to 77%), the specificity was 84% (95% confidence interval, 67% to 93%), and the diagnostic accuracy was 73% (95% confidence interval, 60% to 83%). The sensitivity was 13% (95% confidence interval, 2% to 49%) for grade-I lesions and 83% (95% confidence interval, 59% to 94%) for grade-II, III, or IV lesions. Chondromalacia patellae cannot be diagnosed on the basis of symptoms or with current physical examination methods. The present study demonstrated no correlation between the severity of chondromalacia patellae and the clinical symptoms of anterior knee pain syndrome. Thus, symptoms of anterior knee pain syndrome should not be used as an indication for knee arthroscopy. The sensitivity of 1.0-T magnetic resonance imaging was low for grade-I lesions but considerably higher for more severe (grade-II, III, or IV) lesions. Magnetic resonance imaging may be considered an accurate diagnostic tool for identification of more severe cases of chondromalacia patellae.

The bovine patella as a model of early osteoarthritis.

PubMed

Hargrave-Thomas, E J; Thambyah, A; McGlashan, S R; Broom, N D

2013-12-01

The bovine patella model has been used extensively for studying important structure-function aspects of articular cartilage, including its degeneration. However, the degeneration seen in this model has, to our knowledge, never been adequately compared with human osteoarthritis (OA). In this study, bovine patellae displaying normal to severely degenerate states were compared with human tissue displaying intact cartilage to severe OA. Comparisons of normal and OA features were made with histological scoring, morphometric measurements, and qualitative observations. Differential interference contrast microscopy was used to image early OA changes in the articular cartilage matrix and to investigate whether this method provided comparable quality of visualisation of key structural features with standard histology. The intact bovine cartilage was found to be similar to healthy human cartilage and the degenerate bovine cartilage resembled the human OA tissues with regard to structural disruption, cellularity changes, and staining loss. The extent of degeneration in the bovine tissues matched the mild to moderate range of human OA tissues; however, no bovine samples exhibited late-stage OA. Additionally, in both bovine and human tissues, cartilage degeneration was accompanied by calcified cartilage thickening, tidemark duplication, and the advancement of the cement line by protrusions of bony spicules into the calcified cartilage. This comparison of degeneration in the bovine and human tissues suggests a common pathway for the progression of OA and thus the bovine patella is proposed to be an appropriate model for investigating the structural changes associated with early OA. © 2013 Anatomical Society.

The bovine patella as a model of early osteoarthritis

PubMed Central

Hargrave-Thomas, E J; Thambyah, A; McGlashan, S R; Broom, N D

2013-01-01

The bovine patella model has been used extensively for studying important structure–function aspects of articular cartilage, including its degeneration. However, the degeneration seen in this model has, to our knowledge, never been adequately compared with human osteoarthritis (OA). In this study, bovine patellae displaying normal to severely degenerate states were compared with human tissue displaying intact cartilage to severe OA. Comparisons of normal and OA features were made with histological scoring, morphometric measurements, and qualitative observations. Differential interference contrast microscopy was used to image early OA changes in the articular cartilage matrix and to investigate whether this method provided comparable quality of visualisation of key structural features with standard histology. The intact bovine cartilage was found to be similar to healthy human cartilage and the degenerate bovine cartilage resembled the human OA tissues with regard to structural disruption, cellularity changes, and staining loss. The extent of degeneration in the bovine tissues matched the mild to moderate range of human OA tissues; however, no bovine samples exhibited late-stage OA. Additionally, in both bovine and human tissues, cartilage degeneration was accompanied by calcified cartilage thickening, tidemark duplication, and the advancement of the cement line by protrusions of bony spicules into the calcified cartilage. This comparison of degeneration in the bovine and human tissues suggests a common pathway for the progression of OA and thus the bovine patella is proposed to be an appropriate model for investigating the structural changes associated with early OA. PMID:24111904

Standardization of a Patella spp. (Mollusca, Gastropoda) embryo-larval bioassay and advantages of its use in marine ecotoxicology.

PubMed

Pérez, Sara; Fernández, Nuria; Ribeiro, Pedro A

2016-05-01

The use of three limpet species, Patella vulgata Linnaeus, 1758, Patella depressa Pennant, 1777 and Patella ulyssiponensis Gmelin, 1791 as model organisms in marine ecotoxicology has been evaluated. Initial laboratory experiments were aimed to standardize a biological test with embryos and larvae of Patella spp, establishing the percentage of normal trochophore larvae as endpoint. Before conducting in vitro fertilization, oocytes must be maturated artificially by incubation in an alkaline solution; therefore, alkalinizing agent, pH and time of eggs alkalinization were evaluated. Moreover, time of sperm activation, optimum sperm and oocytes concentration during fertilization, gamete contact time, use of stirring during the fertilization, egg concentration and incubation temperature were examined. Minimum sample size per treatment was also estimated. Exposure of oocytes for 10min to FSW alkalinized with NH4OH at pH 9.0, the use of undiluted sperm pre-activated during 45min and a concentration of 200 oocytesmL(-1), a gamete-contact time of 180min and egg incubation at 18°C during 24h at a concentration of 80 eggsmL(-1) were the conditions allowing maximal embryo-larval development success. With an error of 0.05, a sampling size ≥320 allows a 95% confidence in the estimate. This Patella spp. acute bioassay fulfills a number of important a priori requirements to be used in ecotoxicological studies. Nevertheless, in vitro fertilization requires considerable handling, which may lead to failure in fecundation. Such difficulties are also addressed, in order to facilitate the routine use of this protocol by other laboratories. Copyright © 2016 Elsevier Inc. All rights reserved.

What are the important surgical factors affecting the wound healing after primary total knee arthroplasty?

PubMed

Harato, Kengo; Tanikawa, Hidenori; Morishige, Yutaro; Kaneda, Kazuya; Niki, Yasuo

2016-01-13

Wound condition after primary total knee arthroplasty (TKA) is an important issue to avoid any postoperative adverse events. Our purpose was to investigate and to clarify the important surgical factors affecting wound score after TKA. A total of 139 knees in 128 patients (mean 73 years) without severe comorbidity were enrolled in the present study. All primary unilateral or bilateral TKAs were done using the same skin incision line, measured resection technique, and wound closure technique using unidirectional barbed suture. In terms of the wound healing, Hollander Wound Evaluation Score (HWES) was assessed on postoperative day 14. We performed multiple regression analysis using stepwise method to identify the factors affecting HWES. Variables considered in the analysis were age, sex, body mass index (kg/m(2)), HbA1C (%), femorotibial angle (degrees) on plain radiographs, intraoperative patella eversion during the cutting phase of the femur and the tibia in knee flexion, intraoperative anterior translation of the tibia, patella resurfacing, surgical time (min), tourniquet time (min), length of skin incision (cm), postoperative drainage (ml), patellar height on postoperative lateral radiographs, and HWES. HWES was treated as a dependent variable, and others were as independent variables. The average HWES was 5.0 ± 0.8 point. According to stepwise forward regression test, patella eversion during the cutting phase of the femur and the tibia in knee flexion and anterior translation of the tibia were entered in this model, while other factors were not entered. Standardized partial regression coefficient was as follows: 0.57 in anterior translation of the tibia and 0.38 in patella eversion. Fortunately, in the present study using the unidirectional barbed suture, major wound healing problem did not occur. As to the surgical technique, intraoperative patella eversion and anterior translation of the tibia should be avoided for quality cosmesis in primary TKA.

A magnetic resonance imaging study of abnormalities of the patella and patellar tendon that predispose children to acute patellofemoral dislocation.

PubMed

Yılmaz, Barış; Çiçek, Esin Derin; Şirin, Evrim; Özdemir, Güzelali; Karakuş, Özgün; Muratlı, Hasan Hilmi

This study compared 20 children hospitalised with acute patellofemoral dislocation with an age-matched healthy control group with no history of knee problems or patellar dislocation. The following morphological parameters were significantly different between the groups: the mean patellar width and length, mean sulcus depth, mean patellar tendon width and total patellar volume. The magnetic resonance imaging findings of this study suggested that structurally smaller than normal patella and patellar tendon volumes are predisposing factors for acute patellofemoral dislocation. Copyright © 2016 Elsevier Inc. All rights reserved.

[Surgical Techniques for Patella Replacement in Cases of Deficient Bone Stock in Revision TKA].

PubMed

Ritschl, P; Machacek, F; Strehn, L; Kloiber, J

2015-06-01

The patella replacement in revision surgery is a challenge especially in cases of unsufficient bone stock. Depending on the extent of the bone defect, the following videos demonstrate different approaches: Video 1: bone sparing removal of the patella implant: onlay-type patella implants. Video 2: complete cortical bone rim of the patella, residual thickness between 6 to 10 mm: biconvex patella implant. Video 3 and 4: small defects of the cortical bone rim of the patella, residual thickness 1 to 5 mm (patella shell): gull-wing osteotomy, patella bone grafting techniques. Video 5: partial necrosis/defect of the patella shell with incomplete cortical bone rim: porous tantalum patella prosthesis. On account of the various surgical options for different bone defects of the patella, patellectomy and pure patelloplasty should be avoided to prevent functional shortcomings. Georg Thieme Verlag KG Stuttgart · New York.

Outcome of prosthesis matched and unmatched patella components in primary and revision total knee replacement.

PubMed

Lewis, Peter L; Gamboa, Ai E; Campbell, David G; Lorimer, Michelle

2017-10-01

Although knee replacements have specifically designed patella prostheses that correspond to the geometry of their femoral components, a patella prosthesis that is unmatched to the femoral component may occasionally be inserted. In revision total knee arthroplasty (TKA), an originally resurfaced patella may be left, but the femoral component revised to one that does not match the patella. Few studies have compared the outcome of matched and unmatched patella components in TKA. This study compared the primary or revision TKA outcome of procedures where patella components matched to their femoral counterparts were inserted, with procedures using patella and femoral components that were unmatched. Data on all primary and revision TKA procedures without a patella component or a matched or an unmatched patella component were obtained from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). Revision surgery was the outcome measure. Cumulative percent revised (CPR) were calculated and Hazard ratios with p values were used to test statistical significance. In primary TKA, there were higher rates of revision where unmatched patella components were used, regardless of implant design. There was no difference in the second revision rates of unmatched versus matched patella component groups. This was evident where delayed resurfacing was carried out, and where the patella prosthesis was left alone but the femoral component was changed. All primary TKA procedures require a patella component corresponding to the femoral component if the patella is resurfaced. Conversely, revision knee arthroplasties are not affected by the use of dissimilar patella and femoral components. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of anterior knee pain in a PS total knee arthroplasty: the role of patella-friendly femoral component and patellar size.

PubMed

Atzori, F; Sabatini, L; Deledda, D; Schirò, M; Lo Baido, R; Baido, R L; Massè, A

2015-04-01

Total knee arthroplasty gives excellent objective results. Nevertheless, the subjective findings do not match the normal knee perception: Often, it depends on patellar pain onset. In this study, we analyzed clinical and radiological items that can affect resurfaced patellar tracking, and role of a patella-friendly femoral component and patellar size on patellar pain onset. Thirty consecutive patients were implanted using the same-cemented posterior-stabilized TKA associated with patella resurfacing. Fifteen patients were implanted using a classical femoral component, while another 15 patients were implanted using a patella-friendly femoral component. The statistical analysis was set to detect a significant difference (p < 0.05) in clinical and radiological outcomes related to several surgical parameters. Clinical and functional outcomes were recorded using the Knee Society Scoring System (KSS) and patellar pain with the Burnett questionnaire. Mean follow-up was 25 months. KSS results were excellent in both groups. Group 2 (patella-friendly femoral model) reached a higher percentage of 100 points in the clinical and functional KSS, but there was no statistical difference. Also, no statistical differences for Burnett Questionnaire results were recorded. We had one case of patellar clunk syndrome in the standard femoral component group and one poor result in the second group. Postoperative radiographic measurements evidenced no statistical differences in both groups. In group 1 (classical femoral component), better significant result (p < 0.05) war recorded at clinical evaluation according to the Knee Society Scoring System (KSS) in case of wider patellar component resurfaced. The present study reveals no statistically significant difference in the incidence of anterior knee pain between classical and "patella-friendly" femoral components. With the particular type of implant design utilized in this study, when the classical femoral component is used, bigger patellar implant sizes (38 and 41 mm) showed superior clinical outcome.

[Comparison of therapeutic effects between patella replacement and patella osteotomy in total knee arthroplasty: a case-control study].

PubMed

Tang, Xiao-Bo; Dong, Pei-Long; Wang, Jian

2014-04-01

To compare therapeutic effects between patella replacement and patella osteotomy in total knee arthroplasty. From April 2004 to April 2011, 52 patients (54 knees) were enrolled in the clinical trail of total knee arthroplasty, who received patella replacement (24 knees, including 13 males and 11 females,ranging in age from 53 to 78 years old or patella osteotomy (30 knees,including 16 males and 12 females,ranging in age from 55 to 79 years old. The average follow-up period was 56 months,ranging from 20 to 80 months. The American HSS Score for knee, the Feller score for patella, range of motion (ROM) for knee, patient satisfaction and complications related to the patella were used to evaluate therapeutic effects. In the patella replacement group,the preoperative and final follow-up HSS scores of patients were 38.4 +/- 8.2 and 91.2 +/- 8.6 respectively; Feller scores were 13.6 +/- 6.2 and 25.2 +/- 4.2; scores of anterior knee pain were 3.9 +/- 3.2 and 11.2 +/- 3.7; ROM were (78 +/- 26) degrees and(108 +/- 18) degrees. In the patella osteotomy group,the preoperative and final follow-up HSS scores of patients were 39.5 +/- 8.4 and 91.0 +/- 8.5 respectively;Feller scores were 13.4 +/- 6.5 and 25.6 +/- 4.0; scores of anterior knee pain were 3.7 +/- 3.1 and 11.3 +/- 3.6; ROM were (76 +/- 27) degrees and (110 +/- 19) degrees. In the patella replacement group,patient's satisfaction was 91%, and complication related to the patella was 16.7%; in the patella osteotomy group, patient's satisfaction was 89%, and complications related to the patella was 10.0%. There were no statistically significant differeneces in final follow-up HSS scores, Feller scores, scores of anterior knee pain and ROM between the two groups. However,there was no significant difference of patient's satisfaction between them. There was statistically significant differenece of patella-related complications between the two groups, and the complication rate in the patella replacement group was higher than that in the patella osteotomy group. Total knee arthroplasty with patella replacement or patella osteotomy dramatically relieves pain and improves the knee function. Patella-related complications are associated with its treatment methods, but post-operative anterior knee pain and patient's satisfaction are not related to treatment methods of the patella.

Separate Vertical Wirings for the Extra-articular Fractures of the Distal Pole of the Patella.

PubMed

Kim, Young Mo; Yang, Jun Young; Kim, Kyung Cheon; Kang, Chan; Joo, Yong Bum; Lee, Woo Yong; Hwang, Jung Mo

2011-12-01

To evaluate the usefulness of separate vertical wirings for extra-articular fracture of distal pole of patella. We have analyzed the clinical results of 18 cases that underwent separate vertical wirings for extra-articular fracture of distal pole of the patella from March 2005 to March 2010, by using the range of motion and Bostman score. Occurrence of complication was also evaluated. Additionally, by taking simple radiographs, the correlation between the postoperative degree of anterior transposition of bone fragment and the time of bone fusion, preoperative length of bone fragment, and occurrence of comminuted fracture were investigated. It took an average of 13.8 weeks for radiological bone union after separate vertical wiring fixation. Flexion contracture was an average of 0.8 degrees and further flexion was an average of 127.6°, and Bostman score was an average of 27.5 points (excellent in 12 cases, and good in 6 cases). On the first postoperative year, average flexion contracture was 0.6 degrees and further flexion was an average of 136.3°, which exhibited increased joint motion and recovery to normal range of motion, and Bostman score was an average of 28.7 points (excellent in 16 cases, and good in 2 cases). There was no statistically significant difference between the preoperative bone fragment length and presence of comminution, and degree of anterior transposition of bone fragment after fracture union on simple radiograph (p=0.175, p=0.146). We were able to obtain satisfactory clinical results, while preserving the bone fragment by separate vertical wiring fixation for extra-articular fracture of distal pole of patella. Moreover, the method is easy to perform, which is also considered as a useful surgical method for extra-articular fracture of distal pole of patella.

[Preliminary investigation on the pathogeny, diagnosis and treatment of chondromalacia patella].

PubMed

Ye, Q B; Wu, Z H; Wang, Y P; Lin, J; Qiu, G X

2001-04-01

This paper presents the preliminary investigation on chondromalacia patella at our department in recent years. A random cluster sampling survey covering 2743 normal persons was carried out. The prevalence rate is 36.2%. It was found that, applying transmission electron microscope and immunohistochemical methods on to cartilage tissues of the abnormal region, articular cartilage necrosis was in direct proportion with the abnormal pressure, while the restoration capability of local chondrocytes was in inverse proportion with pathological changes and the pressure. The chondromalacia patella was produced by repeated abnormal stress acting on the cartilage. The stress derived from the uncongruency and the decreasing in the contact area of patellofemoral joint when the subluxation or tilt of patellae was caused by the abnormal anatomical and biomechanical relationship. The initial lesion was at the matrix of cartilage, the collagen network was disrupted, then proteoglycan was lost. The microenvironment of chondrocytes was changed with degradation of matrix. So the chondrocytes became degenerative and necrosis from superficial to deep layer, then feed back the matrix again. Finally, the total cartilage layer might disappear, and the bone under cartilage might proliferate. At late stage, the cartilage was completely destroyed and had no self-restorative ability. Therefore, early diagnosis and treatment are necessary. It is highly suggested axis radiograph of the knee with the tibiae tuberositas localization are helpful to early diagnosis. Furthermore, JKY-Muscle Rehabilitation Instrument is invented for non-operative therapy. It enhances muscle power by selective training of the vastus medialis muscle using electrical stimulator to relieve pain and correct subluxation of patella with 90% efficiency (63% of excellent-effective rate). In late stage, patellofemoral replacement is recommended. The excellent-effective rate is 86.3%.

Developmental anomaly of ossification type patella partita.

PubMed

Oohashi, Yoshikazu

2015-04-01

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. 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. 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. 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. V.

Treating patella fractures with a fixed-angle patella plate-A prospective observational study.

PubMed

Wild, Michael; Fischer, Kai; Hilsenbeck, Florian; Hakimi, Mohssen; Betsch, Marcel

2016-08-01

Anterior tension wiring using Kirschner wires (K-wires) is still considered the standard treatment for patella fractures, despite its high complication rate. The objective of this prospective clinical study was to evaluate intra- and perioperative complications as well as the clinical outcome of patients with patella fracture treated with a new developed bilateral, polyaxial, fixed-angle 2.7mm patella plate. Between 2011 and 2014 all patients with a patella fracture were included in this prospective study and treated with a fixed-angle patella plate. Avulsion fractures of the inferior or superior pole of the patella were excluded. All fractures were classified according to the AO/OTA fracture classification. During a twelve-month follow up period all intra- and postoperative complications were recorded as well as the time until fracture healing. One year postoperatively the Lysholm Score, the pre- and postoperative Tegner Score, the Hospital for Special Surgery Knee Score (HSS), the Turba Score, the Oxford Knee Score, the Knee injury and Osteoarthritis Outcome Score (KOOS), the Bostman Score and the Iowa Knee Score were surveyed. Altogether, 20 patella fractures in 19 patients were included in this prospective study. The most frequent type of fracture, n=10, was a simple transverse patella fracture (C1), followed by 7 comminuted patella fractures (C3) and 3 T-shaped patella fractures (C2). During the 12-month follow up period two patients treated with the patella plate had a complication. In one patient a superficial wound infection occurred, which was treated successfully with hardware removal and in one patient a fracture dislocation due to an implant failure occurred. X-rays demonstrated complete bony healing in all fractures on average 3.2 months postoperatively. All knee scores showed good to excellent clinical results one year postoperatively. The results of this first clinical study indicate that the fixed-angle patella plate is an effective and safe treatment option for patella fractures with a short operative learning curve. The treatment of communited patella fractures (C3) with a fixed-angle patella plate should be well-considered to avoid distending the indication and biomechanical properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

Does patella position influence ligament balancing in total knee arthroplasty?

PubMed

Yoon, Jung-Ro; Oh, Kwang-Jun; Wang, Joon Ho; Yang, Jae-Hyuk

2015-07-01

In vivo comparative gap measurements were performed in three different patella positions (reduced, subluxated and everted) using offset-type-force-controlled-spreader-system. Prospectively, 50 knees were operated by total knee arthroplasty using a navigation-assisted gap-balancing technique. The offset-type-force-controlled-spreader-system was used for gap measurements. This commercially available instrument allows controllable tension in patella-reduced position. The mediolateral gaps of knee extension (0°) and flexion (90°) angle were recorded in three different patella positions; reduced, subluxated and everted. Any gap differences of more than 3 mm were considered as a meaningful difference. Correlation between the difference with the demographic data, preoperative radiologic alignment and intraoperative data was analysed. For statistical analysis, ANOVA and Pearson's correlation test were used. The gaps in patella eversion demonstrated smaller gaps both in knee extension and flexion position compared to the gaps of patella reduction position. The amount of decreased gaps was more definite in knee flexion position. Statistically significant difference was observed for the lateral gap of patella eversion compared to gap of patella reduction in knee flexion position (p < 0.05). There were notable cases of variability in knee flexion position. Significant portion of 12 (24 %) knees of patella subluxation and 33 (66 %) knees of patella evertion demonstrated either increased or decreased gaps in knee flexion position compared to the gaps of patella reduction position. The gaps in patella eversion demonstrated smaller gaps both in knee extension and flexion position compared to the gaps of patella reduction position. The amount of decreased gaps was more definite in knee flexion position. Therefore, the intraoperative patellar positioning has influence on the measurement of the joint gap. Keeping the patella in reduced position is important during gap balancing. I.

Increased serum cartilage oligomeric matrix protein levels and decreased patellar bone mineral density in patients with chondromalacia patellae

PubMed Central

Murphy, E; FitzGerald, O; Saxne, T; Bresnihan, B

2002-01-01

Background: Chondromalacia patellae is a potentially disabling disorder characterised by features of patellar cartilage degradation. Objective: To evaluate markers of cartilage and bone turnover in patients with chondromalacia patellae. Methods: 18 patients with chondromalacia patellae were studied. Serum cartilage oligomeric matrix protein (s-COMP) and bone sialoprotein (s-BSP) levels were measured by enzyme linked immunosorbent assay (ELISA) and compared with those of age and sex matched healthy control subjects. Periarticular bone mineral density (BMD) of both knee joints was assessed by dual energy x ray absorptiometry (DXA). Results: s-COMP levels were significantly raised in all patients with chondromalacia patellae compared with healthy control subjects (p=0.0001). s-BSP levels did not differ significantly between the groups (p=0.41). BMD of the patella was significantly reduced in patients with chondromalacia patellae compared with the control subjects (p=0.016). In patients with bilateral chondromalacia patellae, BMD of the patella was lower in the more symptomatic knee joint (p=0.005). Changes in periarticular BMD were localised to the patella and were not present in femoral regions. Neither s-COMP (p=0.18) nor s-BSP (p=0.40) levels correlated with patellar BMD. Conclusions: Increased s-COMP levels, reflecting cartilage degradation, and reduced BMD localised to the patella may represent clinically useful markers in the diagnosis and monitoring of patients with chondromalacia patellae. Measures of cartilage degradation did not correlate with loss of patellar bone density, suggesting dissociated pathophysiological mechanisms. PMID:12379520

Increased serum cartilage oligomeric matrix protein levels and decreased patellar bone mineral density in patients with chondromalacia patellae.

PubMed

Murphy, E; FitzGerald, O; Saxne, T; Bresnihan, B

2002-11-01

Chondromalacia patellae is a potentially disabling disorder characterised by features of patellar cartilage degradation. To evaluate markers of cartilage and bone turnover in patients with chondromalacia patellae. 18 patients with chondromalacia patellae were studied. Serum cartilage oligomeric matrix protein (s-COMP) and bone sialoprotein (s-BSP) levels were measured by enzyme linked immunosorbent assay (ELISA) and compared with those of age and sex matched healthy control subjects. Periarticular bone mineral density (BMD) of both knee joints was assessed by dual energy x ray absorptiometry (DXA). s-COMP levels were significantly raised in all patients with chondromalacia patellae compared with healthy control subjects (p=0.0001). s-BSP levels did not differ significantly between the groups (p=0.41). BMD of the patella was significantly reduced in patients with chondromalacia patellae compared with the control subjects (p=0.016). In patients with bilateral chondromalacia patellae, BMD of the patella was lower in the more symptomatic knee joint (p=0.005). Changes in periarticular BMD were localised to the patella and were not present in femoral regions. Neither s-COMP (p=0.18) nor s-BSP (p=0.40) levels correlated with patellar BMD. Increased s-COMP levels, reflecting cartilage degradation, and reduced BMD localised to the patella may represent clinically useful markers in the diagnosis and monitoring of patients with chondromalacia patellae. Measures of cartilage degradation did not correlate with loss of patellar bone density, suggesting dissociated pathophysiological mechanisms.

In Vivo Patellar Tracking and Patellofemoral Cartilage Contacts during Dynamic Stair Ascending

PubMed Central

Suzuki, Takashi; Hosseini, Ali; Li, Jing-Sheng; Gill, Thomas J; Li, Guoan

2012-01-01

The knowledge of normal patellar tracking is essential for understanding of the knee joint function and for diagnosis of patellar instabilities. This paper investigated the patellar tracking and patellofemoral joint contact locations during a stair ascending activity using a validated dual-fluoroscopic imaging system. The results showed that the patellar flexion angle decreased from 41.9° to 7.5° with the knee extension during stair ascending. During first 80% of the activity, the patella shifted medially about 3.9 mm and then slightly shifted laterally during the last 20% of the ascending activity. Anterior translation of 13 mm of the patella was measured at the early 80% of the activity and then slightly moved posteriorly by about 2 mm at the last 20% of the activity. The path of the cartilage contact points was slightly lateral on the cartilage surfaces of patella and femur. On the patellar cartilage surface, the cartilage contact locations were about 2 mm laterally from heel strike to 60% of the stair ascending activity and moved laterally and reached 5.3 mm at full extension. However, the cartilage contact locations were relatively constant on the femoral cartilage surface (~5 mm lateral). The patellar tracking pattern was consistent with the patellofemoral cartilage contact location pattern. These data could provide baseline knowledge for understanding of normal physiology of the patellofemoral joint and can be used as a reference for clinical evaluation of patellofemoral disorder symptoms. PMID:22840488

Functional outcomes after operatively treated patella fractures.

PubMed

LeBrun, Christopher T; Langford, Joshua R; Sagi, H Claude

2012-07-01

To evaluate the midterm functional outcomes of patients with isolated operatively treated patella fractures. Prospective cohort and retrospective clinical and radiographic assessment. A Level I and Level II trauma center. Two hundred forty-one patients underwent operative intervention for a displaced patella fracture between 1991 and 2007. After appropriate exclusions, 110 patients met criteria. A total of 40 (36%) patients with isolated, unilateral, operatively treated patella fractures with minimum 1-year follow-up agreed to participate in this study and return for functional testing. Mean follow-up was 6.5 years (range, 1.25-17 years). Enrolled patients were treated with one of the following methods: standard tension band with Kirschner wires, tension band through 2 cannulated screws, longitudinal anterior banding with cerclage, or partial patellectomy. All enrolled patients were evaluated with the SF-36 and an injury-specific questionnaire (Knee Injury and Osteoarthritis Outcome Scores) and asked to self-report symptomatic hardware. Patients were also evaluated by physical examination assessing range of motion and Biodex bilateral quadriceps isometric and isokinetic comparisons. The mean normalized SF-36 physical composite score and the mean normalized Knee Injury and Osteoarthritis Outcome Scores subscale scores (pain, 71.7; symptoms, 66.3; activities of daily living, 75.1; sport/recreation, 45.2; quality of life, 49.6) were statistically different (P < 0.05) from reference population norms. Removal of symptomatic fixation was required in 52% of the patients treated with osteosynthesis, whereas 38% of those with retained fixation self-reported implant-related pain at least some of the time. Eight patients (20%) had an extensor lag greater than 5°. A restricted range of flexion of greater than 5° was noted in 15 patients (38%) and restricted range of extension of greater than 5° was noted in 6 patients (15%). Biodex dynamometric testing revealed a mean isometric extension deficit of 26% between the uninvolved and involved sides for peak torque. Extension power was also tested with an angular velocity of 90°/sec and 180°/sec and mean deficits of 31% and 29% were noted, respectively, when compared with the contralateral extremity. At a mean of 6.5 years after operative treatment for patella fractures, significant symptomatic complaints and functional deficits persist based on validated outcome measures as well as objective physical evaluations. This study fills a void in the literature regarding the functional outcomes of these patients. It also underscores the complexity associated with treating this common fracture and should help guide surgeons to better counsel patients on the expected long-term function after operative treatment of patella fractures. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Content and synthesis of nucleic acids in the cartilage in chondromalacia patellae.

PubMed

Lund, F; Telhag, H

1978-12-01

The content and the synthesis of nucleic acids in chondromalacian, osteoarthritis and normal cartilage was compared. The chondromalacian cartilage differed from osteoarthritis in that the content of nucleic acids was less. Also, the cell density was less in chondromalacian than in normal cartilage as opposed to previous findings in osteoarthritis. The synthesis of DNA was greater in chondromalacian than in normal cartilage but less than in osteoarthritis. With regard to the RNA synthesis, however, the chondromalacian cartilage showed a higher rate than both normal and osteoarthritic cartilage.

Analysis of Impingement between Patella Bone and Bearing Post in Cruciate-Substituting High-Flexion Total Knee Arthroplasty

PubMed Central

Chon, Jegyun; Shin, Sangyeop; Jang, Gunil; Jeon, Taehyeon

2016-01-01

Background We investigated the causes of impingement between the patella bone and the bearing post during high flexion in cruciate-substituting total knee arthroplasty and proposed a treatment strategy. Methods This prospective cohort study included 218 cases that had undergone cruciate-substituting total knee arthroplasty from February 2014 to January 2015; a single surgeon performed the operation using the same method without patellar resurfacing in all patients. Results In these patients, the occurrence of impingement was determined by performing more than 120° high knee flexion after inserting a bearing perioperatively. The incidence of impingement was significantly associated with bearing design, femoral implant size, patella bone length, and patella inferior pole angle (p < 0.05). The impingement was resolved by resection of the lower articular side of the patella bone. Conclusions In the cruciate-substituting high-flexion total knee arthroplasty, impingement between the patella bone and bearing post was more common in patients with mobile bearing, small-size femoral component, and a long patella or a large inferior pole angle. In cases of intraoperative impingement between the patella bone and the bearing post, resection in the lower portion of the patella prevented impingement of the bearing with soft tissue or the patella by widening the space between the patella and the bearing post, which in turn prevented postoperative reduction in range of motion. PMID:27247740

Analysis of Impingement between Patella Bone and Bearing Post in Cruciate-Substituting High-Flexion Total Knee Arthroplasty.

PubMed

Chon, Jegyun; Lee, Bongju; Shin, Sangyeop; Jang, Gunil; Jeon, Taehyeon

2016-06-01

We investigated the causes of impingement between the patella bone and the bearing post during high flexion in cruciate-substituting total knee arthroplasty and proposed a treatment strategy. This prospective cohort study included 218 cases that had undergone cruciate-substituting total knee arthroplasty from February 2014 to January 2015; a single surgeon performed the operation using the same method without patellar resurfacing in all patients. In these patients, the occurrence of impingement was determined by performing more than 120° high knee flexion after inserting a bearing perioperatively. The incidence of impingement was significantly associated with bearing design, femoral implant size, patella bone length, and patella inferior pole angle (p < 0.05). The impingement was resolved by resection of the lower articular side of the patella bone. In the cruciate-substituting high-flexion total knee arthroplasty, impingement between the patella bone and bearing post was more common in patients with mobile bearing, small-size femoral component, and a long patella or a large inferior pole angle. In cases of intraoperative impingement between the patella bone and the bearing post, resection in the lower portion of the patella prevented impingement of the bearing with soft tissue or the patella by widening the space between the patella and the bearing post, which in turn prevented postoperative reduction in range of motion.

Habitual dislocation of patella: A review

PubMed Central

Batra, Sumit; Arora, Sumit

2014-01-01

Habitual dislocation of patella is a condition where the patella dislocates whenever the knee is flexed and spontaneously relocates with extension of the knee. It is also termed as obligatory dislocation as the patella dislocates completely with each flexion and extension cycle of the knee and the patient has no control over the patella dislocating as he or she moves the knee1. It usually presents after the child starts to walk, and is often well tolerated in children, if it is not painful. However it may present in childhood with dysfunction and instability. Very little literature is available on habitual dislocation of patella as most of the studies have combined cases of recurrent dislocation with habitual dislocation. Many different surgical techniques have been described in the literature for the treatment of habitual dislocation of patella. No single procedure is fully effective in the surgical treatment of habitual dislocation of patella and a combination of procedures is recommended. PMID:25983506

Plating of patella fractures: techniques and outcomes.

PubMed

Taylor, Benjamin C; Mehta, Sanjay; Castaneda, Joaquin; French, Bruce G; Blanchard, Chris

2014-09-01

Operative treatment of displaced patella fractures with tension band fixation remains the gold standard, but is associated with a significant rate of complications and symptomatic implants. Despite the evolution of tension band fixation to include cannulated screws, surprisingly little other development has been made to improve overall patient outcomes. In this article, we present the techniques and outcomes of patella plating for displaced patella fractures and patella nonunions.

MRI quantitative morphologic analysis of patellofemoral region: lack of correlation with chondromalacia patellae at surgery.

PubMed

Endo, Yoshimi; Schweitzer, Mark E; Bordalo-Rodrigues, Marcelo; Rokito, Andrew S; Babb, James S

2007-11-01

In numerous studies, the morphologic features of the patellofemoral joint have been analyzed on radiographs. The objective of this study was to assess patellofemoral measurements on MR images and to correlate the measurements with the presence or absence of chondromalacia patellae confirmed at surgery. Axial and sagittal MR images of 98 knees (97 patients) were evaluated. Lateral and medial patellar facet lengths, lateral-to-medial facet length ratio, and interfacet angle were measured at three levels through the patella. Trochlear depth was measured on an axial slice. Patella and patellar tendon lengths, patellar tendon-to-patella ratio, and overlap of the patellar and trochlear articular cartilages were measured on sagittal slices. These measurements in knees with chondromalacia patellae were compared with those in knees without chondromalacia patellae. For assessment of reproducibility, axial measurements were repeated by a second observer. There was no statistically significant difference in any of the axial and sagittal slice measurements between knees with and those without chondromalacia patellae. Interobserver reliability was excellent for measurements of trochlear depth and measurements in the superior and middle aspects of the patella. Measurements through the inferior patella were slightly less reproducible. The results of our study with MRI confirmed many previous radiographic findings. Although we did not find correlation between the presence of chondromalacia patellae and the patellofemoral indexes we analyzed, it is possible that the results of further investigations incorporating different grades of chondromalacia and different locations along the patellar articular surface may lead to further insight regarding the morphologic risk factors for chondromalacia patellae.

When and How Is Patella Tracking Best Assessed in Total Knee Arthroplasty Surgery?

PubMed

Westerman, Richard W; Bhangoo, Navjot S; James, Peter

2016-05-01

Much emphasis has been placed on the role of patella resurfacing in total knee arthroplasty (TKA), yet the impact of soft tissue balancing has frequently been understated. The authors used a novel system to precisely assess patellofemoral joint (PFJ) tracking intraoperatively, to determine the impact of both retinacular reconstruction and tourniquet use on PFJ kinematics. PFJ kinematics assessed intraoperatively for 20 consecutive TKA patients. Measurements were recorded using both the "no thumb technique" and following reconstruction of the retinaculum with two positional sutures. The tourniquet was deflated and both measurements were repeated. Tourniquet inflation was not found to have a significant impact on the patella tracking (mean translation 0.9 mm, p = 0.15). Patella retinacular reconstruction generated a significant medialization of the patella by a mean of 5.5 mm (p < 0.0001) when compared with the traditional retinacular open "no thumb technique." The use of a tourniquet has been shown to have no effect on patella tracking. Reconstruction of the patella retinaculum markedly improves patella tracking, generating a mean medialization of 15%. The authors advocate the routine use of two positional sutures to restore the patella retinaculum, before trialing the patella component, as a reproducible means of assessing the PFJ kinematics. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Patella morphological alteration after patella instability in growing rabbits.

PubMed

Niu, Jinghui; Qi, Qi; Niu, Yingzhen; Dong, Conglei; Dong, Zhenyue; Cui, Peng; Wang, Fei

2017-07-11

The shape of the patella has been considered to be a predisposing factor resulting in patellar instability, but the effects of abnormal patella position during its development are unclear. The present study evaluated patellar morphological changes after patella instability and evaluated the influence of patellar instability on the patella shape. Twenty rabbits that were 2 months old were included in the study. The left knee of each rabbit, defined as the experimental group (N = 20 knees/group), underwent a medial soft tissue restraint release. The right knee of each rabbit, defined as the control group (N = 20 knees/group), did not undergo any surgical procedures. A CT scan was performed on each knee before surgery and 6 months post-surgery to measure the transverse diameter, thickness, Wiberg index, and Wiberg angle for analysis of the patellar morphological changes. Cross-specimen examination was conducted to evaluate the differences between the experimental group and the control group. The four indices remained the same between the two groups before surgery. However, 6 months after surgery, the mean transverse diameter of the patellae in the experimental group was significantly longer than that in the control group (P < 0.001), while the mean thickness in the experimental group was not significantly greater than that in the control group (P = 0.314), resulting in a flattened shape. The Wiberg indices were not significantly different between the two groups. However, the mean Wiberg angle was higher in the experimental group than in the control group (P < 0.001), which resulted in a flattened articular surface of the patella. The sectional shape and articular surface of the patella became more flattened after patella instability in this study, which indicates that patella dysplasia could be caused by patella instability. Clinically, early intervention for adolescent patients with patella instability is important.

Joint hypermobility in patients with chondromalacia patellae.

PubMed

al-Rawi, Z; Nessan, A H

1997-12-01

The relationship between joint mobility and chondromalacia patellae was reported in a prospective study. A total of 115 patients with chondromalacia patellae were compared with 110 healthy individuals without chondromalacia patellae, matched for age and sex, who served as a control group. The degree of joint mobility was scored on a scale of 0-9. The number of individuals with hypermobile joints and the total mobility scores were significantly higher in patients with chondromalacia patellae when compared to the control group (P < 0.001). There were more hypermobile knees among knee joints with chondromalacia patellae when compared with the knees of the control group (P < 0.01). Chondromalacia patellae were bilateral in 57% of our patients. It occurred more frequently in the longer leg and was associated with quadriceps muscle wasting in 50% of patients. Flat feet and backache were reported significantly more often in patients compared with the control group (P < 0.05). It is concluded that hypermobility of the knee joint may be a contributing factor in the pathogenesis of chondromalacia patellae.

A comparison between the patella and the calcaneus using ultrasound velocity and attenuation as predictors of bone mineral density

NASA Astrophysics Data System (ADS)

Han, S. M.; Davis, J.

1997-10-01

The bone mineral density (BMD), ultrasound velocity (UV) and attenuation were examined in sixteen matched sets of human patellae and calcanei. For the sixteen calcanei, BMD was strongly correlated with all ultrasound parameters. Calcaneal UV appeared to be inferior to attenuation in the ability to predict BMD. For the sixteen patellae, the average UV was found to be greater in the superior/inferior direction than in the anterior/posterior and medial/lateral directions. It was found that patella BMD was significantly correlated with each of three directional ultrasound velocities. The relationship between BMD and ultrasound attenuation parameters was not significant in the patella. A comparative study of the two different bone sets demonstrated that the BMDs of the patella and calcaneus were significantly correlated with each other. Ultrasound velocity of calcaneus, measured in the medial/lateral direction, was not significantly associated with any of three directional ultrasound velocities in the patella. Similarly, ultrasound attenuation parameters of calcaneus were not significantly correlated with those of patella. The present study also demonstrated evidence that when predicting BMDs at their respective sites using ultrasound, the calcaneus appeared to be superior to the patella.

Effects of surgical intervention on trochlear remodeling in pediatric patients with recurrent patella dislocation cases.

PubMed

Sugimoto, Dai; Christino, Melissa A; Micheli, Lyle J

2016-07-01

Patella instability is often encountered among physically active pediatric athletes, and surgical intervention is useful in cases with recurrent patella dislocations, chronic instability, and abnormal alignment. Several surgical procedures have been used for patella-realignment and stabilization, but the effects of surgical intervention on bony trochlear remodeling in skeletally immature patients have not been well studied. We thus present two cases of pediatric recurrent patella dislocations that showed trochlear remodeling following patella-realignment surgery. The first case describes an 11-year-old female treated with a Roux-Golthwait procedure and the second case highlights a 12-year-old male treated with lateral release and medial capsular reefing. The Merchant technique, a radiographic criterion that was designed to evaluate patella alignment in relation to the femoral trochlea groove, including sulcus and congruence angles was used to measure postoperative bony development. Both pediatric patients showed successful outcomes following surgical interventions for chronic patella instability. Using the Merchant technique, both patients showed improved congruence and sulcus angles postoperatively. Patella realignment in skeletally immature patients may be beneficial for promoting trochlear remodeling and deepening of the trochlear groove, which may help protect against future dislocation or subluxation events. Level IV, case report.

Comparison of patella bone strain between females with and without patellofemoral pain: a finite element analysis study.

PubMed

Ho, Kai-Yu; Keyak, Joyce H; Powers, Christopher M

2014-01-03

Elevated bone principal strain (an indicator of potential bone injury) resulting from reduced cartilage thickness has been suggested to contribute to patellofemoral symptoms. However, research linking patella bone strain, articular cartilage thickness, and patellofemoral pain (PFP) remains limited. The primary purpose was to determine whether females with PFP exhibit elevated patella bone strain when compared to pain-free controls. A secondary objective was to determine the influence of patella cartilage thickness on patella bone strain. Ten females with PFP and 10 gender, age, and activity-matched pain-free controls participated. Patella bone strain fields were quantified utilizing subject-specific finite element (FE) models of the patellofemoral joint (PFJ). Input parameters for the FE model included (1) PFJ geometry, (2) elastic moduli of the patella bone, (3) weight-bearing PFJ kinematics, and (4) quadriceps muscle forces. Using quasi-static simulations, peak and average minimum principal strains as well as peak and average maximum principal strains were quantified. Cartilage thickness was quantified by computing the perpendicular distance between opposing voxels defining the cartilage edges on axial plane magnetic resonance images. Compared to the pain-free controls, individuals with PFP exhibited increased peak and average minimum and maximum principal strain magnitudes in the patella. Additionally, patella cartilage thickness was negatively associated with peak minimum principal patella strain and peak maximum principal patella strain. The elevated bone strain magnitudes resulting from reduced cartilage thickness may contribute to patellofemoral symptoms and bone injury in persons with PFP. © 2013 Published by Elsevier Ltd.

Evidence of accumulated stress in Achilles and anterior knee tendons in elite badminton players.

PubMed

Boesen, Anders Ploug; Boesen, Morten Ilum; Koenig, Merete Juhl; Bliddal, Henning; Torp-Pedersen, Soren; Langberg, Henning

2011-01-01

Tendon-related injuries are a major problem, but the aetiology of tendinopathies is unknown. In tendinopathies as well as during unaccustomed loading, intra-tendinous flow can be detected indicating that extensive loading can provoke intra-tendinous flow. The aim of present study is to evaluate the vascular response as indicated by colour Doppler (CD) activity in both the Achilles and patella tendon after loading during high-level badminton matches. The Achilles tendon was subdivided into a mid-tendon, pre-insertional, and insertional region and the anterior knee tendons into a quadriceps-, patella- and tuberositas region. Intra-tendinous flow was measured using both a semi-quantitative grading system (CD grading) and a quantitative scoring system (CF) on colour Doppler. Intra-tendinous flow in the Achilles and anterior knee tendons was examined in fourteen single players before tournament and after 1st and 2nd match, respectively on both the dominant and non-dominant side. All players had abnormal intra-tendinous flow (Colour Doppler ≥ grade 2) in at least one tendon in at least one scan during the tournament. At baseline, only two of the 14 players had normal flow in all the tendons examined. After 1st match, tendencies to higher intra-tendinous flow were observed in both the dominant patella tendon and non-dominant quadriceps tendon (P-values n.s.). After 2nd match, intra-tendinous flow was significant increased in the dominant patella tendon (P = 0.009). In all other locations, there was a trend towards a stepwise increase in intra-tendinous flow. The preliminary results indicate that high amount of intra-tendinous flow was found in elite badminton players at baseline and was increased after repetitive loading, especially in the patella tendon (dominant leg). The colour Doppler measurement can be used to determine changes in intra-tendinous flow after repetitive loading.

Patella fractures associated with accelerated ACL rehabilitation in patients with autogenous patella tendon reconstructions.

PubMed

Brownstein, B; Bronner, S

1997-09-01

Patella fracture is a recognized complication of ACL reconstruction with an autogenous patella tendon graft. Typically, fracture occurs as a result of a fall. The incidence of fracture is approximately 0.5%. Accelerated rehabilitation protocols can place stress on the patella, especially in the initial stages of recovery. Therapists are reminded to observe constraints placed on patients by biological tissues, recovering neuromuscular status, and previous level of conditioning. Rehabilitation protocols should be revised according to these factors.

Bilateral recurrent discloation of the patella associated with below knee amputation: A case report

PubMed Central

Batra, Sumit; Kumar, Ratnesh; Lenka, Prasanna

2005-01-01

Background Recurrent dislocation of the patella in patients with below knee amputation is a known entity. Abnormally high-riding patella (patella alta) and medial patellofemoral ligament insufficiency in these patients predisposes them to patellar instability. The established treatment of this problem is surgical realignment. Case presentation A 25 year old male patient with bilateral below knee amputation presented with bilateral recurrent dislocation of the patella while walking on knees on uneven ground. Clinical and radiographic studies showed patella alta. A simple shoe modification was used to treat this patient. Conclusions A simple shoe modification can be used to treat such a condition which is otherwise treated surgically. PMID:15717922

Partial double-layered patella in a nondysplasic adolescent.

PubMed

García-Mata, Serafín; Hidalgo-Ovejero, Angel

2016-11-01

Double-layered patella (DLP) is a rare patella-formation abnormality reported in association with multiple epiphyseal dysplasia. DLP is one of the five types of bipartite patella, caused by a coronal septum that divides the patella into anterior and posterior segments. Although the double layer of bone has been reported as complete, it may also manifest as partial, as in our case. A 13-year-old male patient attended A&E after accidentally falling and sustaining a direct injury to his left knee, with pain in the anterior surface of the right patella. He was diagnosed with an incomplete vertical fracture of the left patella. An axial view radiography indicated an external partial DLP. No bone dysplasia was found. Computed tomographic scan and MRI showed partial DLP and bone marrow oedema because of the injury in the femoral condyle, but no fracture. The reason for highlighting this type of patella abnormality is to present the case of a patient without bone dysplasia, either partial or incomplete, that has not been reported previously. We also wish to emphasize the importance of not confusing it with a fracture in standard radiographies.

Early outcomes of patella resurfacing in total knee arthroplasty

PubMed Central

Clements, Warren J; Miller, Lisa; Whitehouse, Sarah L; Graves, Stephen E; Ryan, Philip

2010-01-01

Background Patella resurfacing in total knee arthroplasty is a contentious issue. The literature suggests that resurfacing of the patella is based on surgeon preference, and little is known about the role and timing of resurfacing and how this affects outcomes. Methods We analyzed 134,799 total knee arthroplasties using data from the Australian Orthopaedic Association National Joint Replacement Registry. Hazards ratios (HRs) were used to compare rates of early revision between patella resurfacing at the primary procedure (the resurfacing group, R) and primary arthroplasty without resurfacing (no-resurfacing group, NR). We also analyzed the outcomes of NR that were revised for isolated patella addition. Results At 5 years, the R group showed a lower revision rate than the NR group: cumulative per cent revision (CPR) 3.1% and 4.0%, respectively (HR = 0.75, p < 0.001). Revisions for patellofemoral pain were more common in the NR group (17%) than in the R group (1%), and “patella only” revisions were more common in the NR group (29%) than in the R group (6%). Non-resurfaced knees revised for isolated patella addition had a higher revision rate than patella resurfacing at the primary procedure, with a 4-year CPR of 15% and 2.8%, respectively (HR = 4.1, p < 0.001). Interpretation Rates of early revision of primary total knees were higher when the patella was not resurfaced, and suggest that surgeons may be inclined to resurface later if there is patellofemoral pain. However, 15% of non-resurfaced knees revised for patella addition are re-revised by 4 years. Our results suggest an early beneficial outcome for patella resurfacing at primary arthroplasty based on revision rates up to 5 years. PMID:19968604

Cartilage degeneration in the human patellae and its relationship to the mineralisation of the underlying bone: a key to the understanding of chondromalacia patellae and femoropatellar arthrosis?

PubMed

Eckstein, F; Putz, R; Müller-Gerbl, M; Steinlechner, M; Benedetto, K P

1993-01-01

According to the literature subchondral bone plays a significant role in the transmission of load through joints and in the pathogenesis of osteoarthrosis. Therefore the degeneration of the articular cartilage was investigated in the patellae from 30 dissecting-room specimens and of 20 patients, previously submitted to arthroscopy, and subchondral mineralisation of their underlying bone was at the same time assessed by means of CT osteoabsorptiometry. Lateral cartilage lesions were localised over highly mineralised subchondral bone; these appear to be due to long-term stress. They were mainly found in the older specimens and showed a high rate of progression with increasing age. Medially localised cartilage lesions, on the other hand, were situated in a transitional region between moderate and slight subchondral mineralisation; they may be caused by infrequent stress peaks and by shear stress in the articular cartilage, the very medial part of the joint being deprived of mechanical stimulation for much of the time. These lesions were to be found predominantly in the younger specimens and showed little progress with advancing age. Patients with lateral cartilage degeneration exhibited higher, patients with medial chondromalacia patellae lower mineralisation than normals. Their density patterns therefore indicate a different mechanical pathogenesis of the cartilage lesions in the lateral and medial facet. It could be shown that CT osteoabsorptiometry allows an assessment of the mechanical situation, present in individual femoro-patellar joints, and that this situation is highly relevant for the pathogenesis of patellar cartilage degeneration.

Anterior cruciate ligament deterioration correlates with patella osteoarthritis.

PubMed

Iriuchishima, Takanori; Ryu, Keinosuke; Aizawa, Shin; Yorifuji, Hiroshi; Ohyama, Tetsuji; Fu, Freddie H

2014-04-01

The correlation between anterior cruciate ligament (ACL) condition and patella osteoarthritic (OA) changes has not been well reported. The aim of this study was to reveal the correlation between ACL deterioration and the morphology of OA changes in the patella. The hypothesis was that significant correlation between ACL deterioration and patella OA morphology would be revealed in this study. Two hundred ninety-one cadaveric knees from 151 cadavers were included in this study with a median age of 83 years (54-98). Knees were opened with a sub-vastus approach and the ACL condition was classified as intact or deteriorated. Patella OA lesions were classified using Han's method: type 1, no or minimal lesion; type 2, medial facet lesion without involvement of the ridge; type 3, lateral facet lesion without involvement of the ridge; type 4, lesion involving the ridge only; type 5, medial facet lesion with involvement of the ridge; type 6, lateral facet lesion with involvement of the ridge; and type 7, global lesion. OA depth evaluation was performed following Outerbridge's classification. Statistical analysis of the collected data was performed using generalized estimating equations (GEE). The ACL was intact in 277 knees and deteriorated in 14 knees. Patella OA lesions were observed as follows: type 1, 29%; type 2, 15%; type 3, 2%; type 4, 12%; type 5, 18%; type 6, 2%; and type 7, 22%. Outerbridge's classification of over grade 2 OA depth was observed in 73.5% of subjects. When patella OA was divided into types 1-4 and types 5-7, ACL deterioration was correlated with the occurrence of type 5-7 patella OA [OR 6.44, 95%CI 2.27-18.25, p = 0.000]. When patella OA was divided into types 1-6 and type 7, ACL deterioration was correlated with the occurrence of type 7 patella OA [OR 6.02, 95%CI 2.57-14.09, p = 0.000]. When patella OA depth was divided into grades 1-3 and grade 4, ACL deterioration was highly correlated with the occurrence of grade 4 patella OA [OR 9.31, 95%CI 2.96-29.33, p = 0.025]. ACL deterioration is a strong risk factor of wider and deeper OA changes in the patella. For clinical relevance, subjects with ACL tear should be aware of the progression of patella OA.

Defining the lateral and accessory views of the patella: an anatomic and radiographic study with implications for fracture treatment.

PubMed

Berkes, Marschall B; Little, Milton T M; Pardee, Nadine C; Lazaro, Lionel E; Helfet, David L; Lorich, Dean G

2013-12-01

The majority of orthopaedic surgeons rely on a lateral fluoroscopic image to assess reduction during patella fracture osteosynthesis. However, a comprehensive radiographic description of the lateral view of the patella has not been performed previously, and no accessory views to better visualize specific anatomic features have been developed. The purpose of this study was to provide a detailed anatomic description of all radiographic features of the true lateral of the patella, describe reproducible accessory views for assessing specific features of the patella, and demonstrate their utility in a fracture model. Twelve cadaver knee specimens free of patellofemoral pathology were used, and imaging was performed using standard C-arm fluoroscopy. For each specimen, a true lateral radiographic projection of the patella was obtained and distinct features were noted. Next, an arthrotomy was made and steel wire was contoured and fixed to various anatomic regions of the patella so as to obliterate the radiographic densities on the true lateral projection, thus confirming their anatomic correlation. Ideal views of the lateral and medial facets themselves were determined using radiographic markers and varying amounts of internal or external rotation of the specimen. Last, a transverse osteotomy was created in each patella and the ability of the true lateral and accessory views to detect malreduction was assessed. The true lateral projection of the patella was obtained with the limb in neutral alignment. Constant radiographic features of the lateral view of the patella include the articular tangent, a secondary articular density of variable length, and a dorsal cortical density. The articular tangent was produced by the central ridge between the medial and lateral facets in all specimens. The secondary articular density was created by a confluence of the edge of the lateral and edge of the medial facets in 5 patellas, a confluence of the edge of the lateral facet and the intersection of the odd and medial facets in 6 patellas, and the edge of the lateral facet alone in 1 patella. The edge of the lateral facet gave a constant contribution to the appearance of the secondary articular density in all cases. A distinct accessory view of the tangent of the lateral facet could be seen with an average of 17 degrees of patella external rotation (range, 12-35 degrees), and the tangent of the medial facet with an average of 26.5 degrees of internal rotation (range, 15-45 degrees). These accessory views were better able to visualize malreduction than the single lateral projection in a fracture model in all specimens. Described here is a comprehensive description of the true lateral radiographic view of the patella and accessory views. These views can be used in the evaluation of minimally displaced patella fractures if a computerized tomography is not desired to better assess the true amount of displacement and when assessing intraoperative reduction during patella fracture osteosynthesis.

Characterising the proximal patellar tendon attachment and its relationship to skeletal maturity in adolescent ballet dancers

PubMed Central

Rudavsky, Aliza; Cook, Jillianne; Magnusson, Stig Peter; Kjaer, Michael; Docking, Sean

2017-01-01

Summary Background It is unknown how and when the proximal attachment of the patellar tendon matures; puberty may be key in ensuring normal tendon formation. The aim of this study was to investigate the features of the proximal patellar tendon attachment at different stages of skeletal maturity, to help gain an understanding of how and when the tendon attachment matures. Methods Sixty adolescent elite ballet students (ages 11–18) and eight mature adults participated. Peak height velocity (PHV) estimated skeletal maturity. Ultrasound tissue characterisation (UTC) scan was taken of the left knee and analysed for stability of echopattern. An image-based grading scale for greyscale ultrasound was developed to describe the tendon appearance. Anterior-posterior thickness was measured at the inferior pole of the patella, 1 and 2 centimetres distally. Outcomes were compared with skeletal maturity. Results Mid-portion patellar tendon thickness increased with skeletal maturity (p=0.001 at 1 cm and p=0.007 at 2 cm). There was more variance in structural appearance (greyscale classification and UTC echopattern) in pre and peri-PHV participants. Tendon attachment one-year post PHV appeared similar to mature tendons. Conclusions Early adolescence was associated with highly variable tendon appearance, whereas the tendon appeared mature after PHV. Adolescence may be a critical time for the formation of normal tendon attachment. Level of evidence IIb individual cohort study. PMID:29264342

Adolescent patellar instability: current concepts review.

PubMed

Clark, D; Metcalfe, A; Wogan, C; Mandalia, V; Eldridge, J

2017-02-01

Patellar instability most frequently presents during adolescence. Congenital and infantile dislocation of the patella is a distinct entity from adolescent instability and measurable abnormalities may be present at birth. In the normal patellofemoral joint an increase in quadriceps angle and patellar height are matched by an increase in trochlear depth as the joint matures. Adolescent instability may herald a lifelong condition leading to chronic disability and arthritis. Restoring normal anatomy by trochleoplasty, tibial tubercle transfer or medial patellofemoral ligament (MPFL) reconstruction in the young adult prevents further instability. Although these techniques are proven in the young adult, they may cause growth arrest and deformity where the physis is open. A vigorous non-operative strategy may permit delay of surgery until growth is complete. Where non-operative treatment has failed a modified MPFL reconstruction may be performed to maintain stability until physeal closure permits anatomical reconstruction. If significant growth remains an extraosseous reconstruction of the MPFL may impart the lowest risk to the physis. If minor growth remains image intensifier guided placement of femoral intraosseous fixation may impart a small, but acceptable, risk to the physis. This paper presents and discusses the literature relating to adolescent instability and provides a framework for management of these patients. Cite this article: Bone Joint J 2017;99-B:159-70. ©2017 The British Editorial Society of Bone & Joint Surgery.

Running-induced patellofemoral pain fluctuates with changes in patella water content.

PubMed

Ho, Kai-Yu; Hu, Houchun H; Colletti, Patrick M; Powers, Christopher M

2014-01-01

Although increased bone water content resulting from repetitive patellofemoral joint loading has been suggested to be a possible mechanism underlying patellofemoral pain (PFP), there is little data to support this mechanism. The purpose of the current study was to determine whether running results in increases in patella water content and pain and whether 48 hours of rest reduces patella water content and pain to pre-running levels. Ten female runners with a diagnosis of PFP (mean age 25.1 years) participated. Patella water content was quantified using a chemical-shift-encoded water-fat magnetic resonance imaging (MRI) protocol. The visual analog scale (VAS) was used to quantify subjects' pain levels. MRI and pain data were obtained prior to running, immediately following a 40-minute running session, and 48 hours post-running. Pain and patella water content were compared among the 3 time points using one-way ANOVA's with repeated measures. Immediately post-running, persons with PFP reported significant increases in pain and exhibited elevated patella water content. Pain and patella water content decreased to pre-running levels following 48 hours of rest. Our findings suggest that transient changes in patella water content associated with running may, in part, contribute to patellofemoral symptoms.

Acro-spondylo-pubic dysostosis associated with cataracts, microcephaly, and normal intelligence.

PubMed

Chacon-Camacho, Oscar F; Villegas-Ruiz, Vanessa; Buentello-Volante, Beatriz; Piña-Aguilar, Raul E; Peláez-González, Hugo; Ramírez, Magdalena; González-Rodríguez, Johanna; Zenteno, Juan Carlos

2015-02-01

We report on an adult male with normal intelligence who exhibited an unusual combination of microcephaly, dysostoses of limbs, vertebrae, patellae, and pubic bone, camptodactyly of all fingers, and syndactyly of toes, absent nails on thumbs and some fingers, bilateral cataract, cryptorchidism, polythelia, and nipple-like skin pigmentations of shoulders and upper back. We have been unable to find a description of a similar combination of manifestations in literature. The cause of the anomalies remains unknown. © 2014 Wiley Periodicals, Inc.

Anatomy, morphology and evolution of the patella in squamate lizards and tuatara (Sphenodon punctatus).

PubMed

Regnault, Sophie; Jones, Marc E H; Pitsillides, Andrew A; Hutchinson, John R

2016-05-01

The patella (kneecap) is the largest and best-known of the sesamoid bones, postulated to confer biomechanical advantages including increasing joint leverage and reinforcing the tendon against compression. It has evolved several times independently in amniotes, but despite apparently widespread occurrence in lizards, the patella remains poorly characterised in this group and is, as yet, completely undescribed in their nearest extant relative Sphenodon (Rhynchocephalia). Through radiography, osteological and fossil studies we examined patellar presence in diverse lizard and lepidosauromorph taxa, and using computed tomography, dissection and histology we investigated in greater depth the anatomy and morphology of the patella in 16 lizard species and 19 Sphenodon specimens. We have found the first unambiguous evidence of a mineralised patella in Sphenodon, which appears similar to the patella of lizards and shares several gross and microscopic anatomical features. Although there may be a common mature morphology, the squamate patella exhibits a great deal of variability in development (whether from a cartilage anlage or not, and in the number of mineralised centres) and composition (bone, mineralised cartilage or fibrotendinous tissue). Unlike in mammals and birds, the patella in certain lizards and Sphenodon appears to be a polymorphic trait. We have also explored the evolution of the patella through ancestral state reconstruction, finding that the patella is ancestral for lizards and possibly Lepidosauria as a whole. Clear evidence of the patella in rhynchocephalian or stem lepidosaurian fossil taxa would clarify the evolutionary origin(s) of the patella, but due to the small size of this bone and the opportunity for degradation or loss we could not definitively conclude presence or absence in the fossils examined. The pattern of evolution in lepidosaurs is unclear but our data suggest that the emergence of this sesamoid may be related to the evolution of secondary ossification centres and/or changes in knee joint conformation, where enhancement of extensor muscle leverage would be more beneficial. © 2016 The Authors. Journal of Anatomy published by John Wiley & Sons Ltd on behalf of Anatomical Society.

Influence of age on clinical outcomes of three-dimensional transfer of the tibial tuberosity for patellar instability with patella alta.

PubMed

Otsuki, Shuhei; Nakajima, Mikio; Fujiwara, Kenta; Okamoto, Yoshinori; Iida, Go; Murakami, Tomohiko; Neo, Masashi

2017-08-01

To evaluate the clinical outcomes of three-dimensional (3D) transfer of the tibial tuberosity for patellar instability with patella alta, with a focus on the influence of age at initial surgery. Three-dimensional surgery was performed on 28 knees with a mean follow-up of 46 months. Patients were separated into three groups based on the age at initial surgery: group A, 10 knees and an average age of 16.3 ± 1.8 (14-19) years; group B, 10 knees and an average age of 22.1 ± 2.5 (20-28) years; and group C, eight knees and an average age of 44.0 ± 2.2 (40-46) years. Patellofemoral geometry improvement focused on patella alta by determining the Insall-Salvati ratio and Caton-Deschamps index, rotational malalignment by measuring the tibial tubercle-trochlear groove (TT-TG) distance, and lateral patellar subluxation by measuring the patellar tilt. Clinical outcomes were evaluated by the Lysholm and Kujala scores, which were compared before and after surgery. Cartilage degeneration was evaluated by the International Cartilage Repair Society grading system at initial arthroscopy. The patellar height, TT-TG, and patellar tilt significantly improved in all groups postoperatively (p < 0.05). The Lysholm and Kujala scores also significantly improved postoperatively; however, both scores were lower in group C than in the other groups (p < 0.05). Particularly, pain scores were more severe in group C than in the other groups, and the severity of cartilage degeneration correlated with the pain scores (p < 0.05). Cartilage damage differed significantly between the groups at initial arthroscopy; particularly, group C included grades III and IV cartilage degeneration (p < 0.05). Age at initial surgery may be the predicting factor for poor clinical outcomes of 3D transfer surgery. The clinical outcome may depend on the age at surgery, which correlated with cartilage damage; thus, surgeons should be given this information when patients are considered undergoing patella surgery. Therapeutic case series, Level IV.

Detection and staging of chondromalacia patellae: relative efficacies of conventional MR imaging, MR arthrography, and CT arthrography.

PubMed

Gagliardi, J A; Chung, E M; Chandnani, V P; Kesling, K L; Christensen, K P; Null, R N; Radvany, M G; Hansen, M F

1994-09-01

Chondromalacia patellae is a condition characterized by softening, fraying, and ulceration of patellar articular cartilage. We compare the sensitivity, specificity, and accuracy of conventional MR imaging, MR arthrography, and CT arthrography in detecting and staging this abnormality. Twenty-seven patients with pain in the anterior part of the knee were prospectively examined with MR imaging, including T1-weighted (650/16), proton density-weighted (2000/20), T2-weighted (2000/80), and spoiled two-dimensional gradient-recalled acquisition in the steady state (SPGR/)/35 degrees (51/10) with fat saturation pulse sequences. All were also examined with T1-weighted MR imaging after intraarticular injection of dilute gadopentetate dimeglumine and with double-contrast CT arthrography. Each imaging technique was evaluated independently by two observers, who reached a consensus interpretation. The signal characteristics of cartilage on MR images and contour abnormalities noted with all imaging techniques were evaluated and graded according to a modification of the classification of Shahriaree. Twenty-six of the 54 facets examined had chondromalacia shown by arthroscopy, which was used as the standard of reference. The sensitivity, specificity, and accuracy of each imaging technique in the diagnosis of each stage of chondromalacia patellae were determined and compared by using the McNemar two-tailed analysis. Arthroscopy showed that 28 facets were normal. Grade 1 chondromalacia patellae was diagnosed only with MR and CT arthrography in two (29%) of seven facets. Intermediate (grade 2 or 3) chondromalacia patellae was detected in two (13%) of 15 facets with T1-weighted and SPGR MR imaging, in three (20%) of 15 facets with proton density-weighted MR imaging, in seven (47%) of 15 facets with T2-weighted MR imaging, in 11 (73%) of 15 facets with CT arthrography, and in 12 (80%) of 15 facets with MR arthrography. Grade 4 was detected in three (75%) of four facets with T1-, proton density-, and T2-weighted MR imaging, two (50%) of four facets with SPGR MR imaging, and four (100%) of four facets with MR and CT arthrography. Thus, all imaging techniques were insensitive to grade 1 lesions and highly sensitive to grade 4 lesions, so that no significant difference among the techniques could be shown. All imaging techniques studied had high specificity and accuracy in the detection and grading of chondromalacia patella; however, both MR arthrography and CT arthrography were more sensitive than T1-weighted, proton density-weighted, and SPGR with fat saturation MR imaging for showing intermediate grades of chondromalacia patellae. Although the arthrographic techniques were not significantly better than T2-weighted imaging, the number of false-positive diagnoses was greatest with T2-weighted MR imaging.

Recessively inherited multiple epiphyseal dysplasia with normal stature, club foot, and double layered patella caused by a DTDST mutation

PubMed Central

Superti-Furga, A.; Neumann, L.; Riebel, T.; Eich, G.; Steinmann, B.; Spranger, J.; Kunze, J.

1999-01-01

We have observed over 25 different mutations in the diastrophic dysplasia sulphate transporter gene (DTDST) in association with the recessive disorders achondrogenesis 1B, atelosteogenesis 2, and diastrophic dysplasia. The c862t (R279W) transition is the most common mutation in non-Finnish patients, but in these disorders it is usually combined with other DTDST mutations. We had not seen a case of homozygosity for c862t (R279W) until we analysed DNA from a 36 year old male with tall-normal stature (180 cm) who asked for genetic counselling for suspected multiple epiphyseal dysplasia. He was treated for club foot and hip dysplasia at birth. Skeletal changes consistent with multiple epiphyseal dysplasia, with the peculiar finding of a double layered patella, were recognised during childhood. Cleft palate, swelling of the ear pinna, and hitch hiker thumb were absent. He was found to be homozygous, and both healthy parents heterozygous, for the R279W mutation in DTDST, and his fibroblasts showed a sulphate incorporation defect typical of DTDST disorders. Counselling was given for a recessive disorder, thereby considerably reducing the probability of affected offspring.
  Multiple epiphyseal dysplasia is more frequently caused by dominant mutations in the COMP (EDM1, McKusick 132400) and COL9A2 genes (EDM2, McKusick 600204). A few other patients and families with features similar to our proband have been described previously and considered to have autosomal recessive MED (EDM4, McKusick 226900). This observation confirms the existence of this entity and assigns it to the phenotypic spectrum associated with mutations at the DTDST locus.


Keywords: multiple epiphyseal dysplasia; DTDST; double layered patella PMID:10465113

Quantitative stress radiography of the patella and evaluation of patellar laxity before and after lateral release for recurrent dislocation patella.

PubMed

Niimoto, Takuya; Deie, Masataka; Adachi, Nobuo; Usman, Muhammad Andry; Ochi, Mitsuo

2014-10-01

The aims of the present controlled clinical study were to (1) compare patella laxity determined in the outpatient clinic with that in anaesthetized patients and (2) evaluate patella laxity before and after lateral release. The study evaluated data on 33 knees from 33 patients (average age 19.7 years) between 2007 and 2011. All patients were diagnosed with recurrent dislocation of the patella. Patellar stability was evaluated in each patient thrice: patellas were first imaged in the outpatient clinic prior to surgery at 45° knee flexion with 20 N stress from the medial to lateral side and from the lateral to medial side; then, at the time of surgery, patella stress images were obtained in the same manner before and after the lateral release procedure. Radiological assessments were performed using the medial stress shift ratio (MSSR) and lateral stress shift ratio (LSSR). There were no significant differences in the LSSR and MSSR before surgery (outpatient data) and in anaesthetized patients before the lateral release procedure. Furthermore, there was no significant difference in MSSR at the time of surgery before and after the lateral release procedure. However, LSSR increased significantly after the lateral release procedure. The results of the present study suggest that quantitative patella stress radiography in the outpatient clinic is useful when it comes to investigating laxity of the patella, and that lateral release significantly increases lateral, but not medial, laxity in patients with recurrent patellar dislocation. IV.

Comparison of titanium cable tension band and nickel-titanium patella concentrator for patella fractures.

PubMed

Zhao, Quan-Ming; Gu, Xiao-Feng; Cheng, Li; Feng, De-Hong

2017-07-01

Patellar fractures account for approximately 1% of all fractures. Due to the patella's importance as regards the extensor mechanism, effort should be made to preserve the patella. Several operative treatment methods have been introduced for patella fractures. This study aims to compare the clinical effect of a titanium cable tension band and nickeltitanium (NiTi) patella concentrator (NT-PC) in treating patella fractures. Thirty-nine patients with patella fractures were enrolled in this retrospective study. All the patients were treated via the open reduction internal fixation procedure using a titanium cable tension band or NT-PC. All the patients were followed up over an average period of 13 months. The main outcome measures were operation time, time of fracture union, postoperative complications, and Böstman knee scores. Statistical analyses were conducted between the 2 groups. All the patients were operated on successfully. The operation time of the NT-PC treatment group was less than that of the titanium cable tension band treatment group (p < 0.05). The mean scores at the final follow-up were 28.2 and 27.6 points in the titanium cable tension band and NT-PC groups, respectively. No significant difference was observed between the excellent and good results (p > 0.05). Both titanium cable tension band and NT-PC showed good efficacy for the treatment of patellar fractures. NT-PC fixation, a new option for the treatment of patella fractures, is a simple and effective fixation method.

[Traumatic separation of a type I patella bipartite in a sportsman].

PubMed

Ottesen, Casper Smedegaard; Barfod, Kristoffer Weisskirchner; Holck, Kim

2014-05-12

This is a case report of a 44-year-old sportsman who experi-enced acute onset of strong pain and loss of ability to extend his right knee during a game of beach volley. X-ray imaging showed a patella in two parts with rounded edges and with a diastasis of more than 2 cm. Intra-operatively atrophic fibrocartilage was found on both parts of the patella. Asymptomatic patella bi-partite was found on X-ray imaging of the patient's left knee, and he was diagnosed to have traumatic separation of a type I patella bipartite. The diagnosis was confirmed by surgical and radiological findings.

Novel Anterior Plating Technique for Patella Fracture Fixation.

PubMed

Siljander, Matthew P; Vara, Alexander D; Koueiter, Denise M; Wiater, Brett P; Wiater, Patrick J

2017-07-01

Patella fracture fixation remains a significant challenge for orthopedic surgeons. Although tension band fixation allows for reliable osseous union, especially in simple fracture patterns, it still presents several problems. Plate fixation of patella fractures is a method that allows for more rigid stabilization and earlier mobilization. At the authors' level 1 trauma center, one fellowship-trained trauma surgeon has transitioned to using a novel anterior, low-profile mesh plate construct for all types of patella fractures. This construct allows for stable fixation, osseous union, and neutralization of the inferior pole for even the most comminuted of patella fractures. [Orthopedics. 2017; 40(4):e739-e743.]. Copyright 2017, SLACK Incorporated.

Biomechanical Assessment of Locked Plating for the Fixation of Patella Fractures.

PubMed

Wurm, Simone; Augat, Peter; Bühren, Volker

2015-09-01

To analyze the mechanical stability of locked plating in comparison with tension-band wiring for the fixation of fractures of the patella. Biomechanical tests were performed on artificial foam patella specimens comparing an angular stable plate and monocortical screws with tension-band wiring. Tests were performed under combined tension and bending until failure simulating physiological loading of the tibia during walking. Tension-band wiring failed at 66% of the failure load of plating (1052 N, P = 0.002) and had 5 times larger fracture gap displacements (P = 0.002). Based on the biomechanical advantages, locked plating of the patella may constitute a reasonable alternative in the treatment of patella fractures.

Thermography in the detection and follow up of chondromalacia patellae.

PubMed Central

Vujcić, M; Nedeljković, R

1991-01-01

Although diagnostic criteria for chondromalacia patellae exist, the disease is often accompanied by physical signs which are limited or non-diagnostic. Thermographic examination was performed in 157 patients with clinical diagnosis of chondromalacia patellae in 86 patients after surgical treatment for chondromalacia, and in 308 controls. Thermography can help the clinicians in establishing the diagnosis of chondromalacia patellae, but by itself is not sufficiently specific. The specificity of thermography was dependent on age, ranging from 90% for the 15-24 year age group to 65% for the 45-54 year age group. Sensitivity of the method was 68%. Thermography can disclose other knee disorders which imitate chondromalacia patellae. Images PMID:1768161

Menopause is associated with articular cartilage degeneration: a clinical study of knee joint in 860 women.

PubMed

Lou, Chao; Xiang, Guangheng; Weng, Qiaoyou; Chen, Zhaojie; Chen, Deheng; Wang, Qingqing; Zhang, Di; Zhou, Bin; He, Dengwei; Chen, Hongliang

2016-11-01

The purpose of this study was to investigate the association between menopause and severity of knee joint cartilage degeneration using a magnetic resonance imaging-based six-level grading system, with six cartilage surfaces, the medial and lateral femoral condyle, the femoral trochlea, the medial and lateral tibia plateau, and the patella. The study cohort comprised 860 healthy women (age 36-83 y), and 5,160 cartilage surfaces were analyzed. Age, weight, height, age at natural menopause, and years since menopause (YSM) were obtained. Cartilage degeneration was assessed using a magnetic resonance imaging-based six-level grading system. After removing the age, height, and weight effects, postmenopausal women had more severe cartilage degeneration than pre- and perimenopausal women (P < 0.001). A positive trend was observed between YSM and severity of cartilage degeneration (P < 0.05). Postmenopausal women were divided into seven subgroups by every five YSM. When YSM was less than 25 years, the analysis of covariance indicated a significant difference in medial tibia plateau, medial femoral condyle, trochlea, patella, and total surfaces (P < 0.05 or 0.01) between every two groups. When YSM was more than 25 years, the significant difference, however, disappeared in these four surfaces (P > 0.05). No significant difference was observed in lateral tibia plateau and lateral femoral condyle in postmenopausal women. Menopause is associated with cartilage degeneration of knee joint. After menopause, cartilage showed progressive severe degeneration that occurred in the first 25 YSM, suggesting estrogen deficiency might be a risk factor of cartilage degeneration of the knee joint. Further studies are needed to investigate whether age or menopause plays a more important role in the progression of cartilage degeneration in the knee joint.

The use of tibial tuberosity-trochlear groove indices based on joint size in lower limb evaluation.

PubMed

Ferlic, Peter Wilhelm; Runer, Armin; Dirisamer, Florian; Balcarek, Peter; Giesinger, Johannes; Biedermann, Rainer; Liebensteiner, Michael Christian

2018-05-01

The correlation between tibial tuberosity-trochlear groove distance (TT-TG) and joint size, taking into account several different parameters of knee joint size as well as lower limb dimensions, is evaluated in order to assess whether TT-TG indices should be used in instead of absolute TT-TG values. This study comprised a retrospective analysis of knee CT scans, including 36 cases with patellofemoral instability (PFI) and 30 controls. Besides TT-TG, five measures of knee joint size were evaluated in axial CT slices: medio-lateral femur width, antero-posterior lateral condylar height, medio-lateral width of the tibia, width of the patella and the proximal-distal joint size (TT-TE). Furthermore, the length of the femur, the tibia and the total leg length were measured in the CT scanogram. Correlation analysis of TT-TG and the other parameters was done by calculating the Spearman correlation coefficient. In the PFI group lateral condylar height (r = 0.370), tibia width (r = 0.406) and patella width (r = 0.366) showed significant moderate correlations (p < 0.03) with TT-TG. Furthermore, we found a significant correlation between TT-TG and tibia length (r = 0.371) and total leg length (r = 381). The control group showed no significant correlation between TT-TG and knee joint size or between TT-TG and measures of lower limb length. Tibial tuberosity-trochlear groove distance correlates with several parameters of knee joint size and leg length in patients with patellofemoral instability. Application of indices determining TT-TG as a ratio of joint size could be helpful in establishing the indication for medial transfer of the tibial tuberosity in patients with PFI. Level III.

Transverse Stress Fracture of the Proximal Patella: A Case Report.

PubMed

Atsumi, Satoru; Arai, Yuji; Kato, Ko; Nishimura, Akinobu; Nakazora, Shigeto; Nakagawa, Shuji; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Sudo, Akihiro; Kubo, Toshikazu

2016-02-01

Among stress fractures associated with sports activities, patellar stress fracture is rare. Regarding patella stress fractures, so far only distal transverse or lateral longitudinal fractures have been reported, but there are no reports of transverse fractures occurring in the proximal patella. We describe an extremely rare case of transverse stress fracture of proximal patella in a 9-year-old athlete.A 9-year old boy, who participated in sports (sprints and Kendo) presented with left knee pain without any external injury. In plain radiographs, a fracture line was observed in the proximal 1/3 of the left patella, and a patella stress fracture was diagnosed. For treatment, because 7 months of conservative therapy showed no improvement, internal fixation was carried out using Acutrak screws, and bone union was thus achieved. Three months after the operation, he was able to return to his previous level of athletic sports activity.Regarding the mechanism of onset, it is believed that the causes are longitudinal traction force and patellofemoral contact pressure. On the other hand, the contact region of the patella with the femur changes with the flexion angle of the knee. In the current case, the fracture occurred at a site where the patella was in contact with the femur at a flexion angle of >90°, so it is believed that it occurred as a clinical condition from being subjected to repeated longitudinal traction force and patellofemoral contact pressure at a flexion angle of >90°, during the sports activities of sprints and Kendo. The nonunion of the transverse stress fracture of his proximal patella was successfully treated with internal fixation using Acutrak screws.

The influence of malalignment and ageing following sterilisation by gamma irradiation in an inert atmosphere on the wear of ultra-high-molecular-weight polyethylene in patellofemoral replacements

PubMed Central

Maiti, Raman; Cowie, Raelene M; Fisher, John; Jennings, Louise M

2017-01-01

Complications of patellofemoral arthroplasty often occur soon after implantation and, as well as other factors, can be due to the design of the implant or its surgical positioning. A number of studies have previously considered the wear of ultra-high-molecular-weight polyethylene patellae following suboptimal implantation; however, studies have primarily been carried out under a limited number of degrees of freedom. The aim of this study was to develop a protocol to assess the wear of patellae under a malaligned condition in a six-axis patellofemoral joint simulator. The malalignment protocol hindered the tracking of the patella centrally in the trochlear groove and imparted a constant 5° external rotation (tilt) on the patella button. Following 3 million cycles of wear simulation, this condition had no influence on the wear of ultra-high-molecular-weight polyethylene patellae aged for 4 years compared to well-positioned non-aged implants (p > 0.05). However, under the malaligned condition, ultra-high-molecular-weight polyethylene patellae aged 8–10 years after unpacking (following sterilisation by gamma irradiation in an inert atmosphere) and worn ultra-high-molecular-weight polyethylene components also aged 4 years after unpacking (following the same sterilisation process) exhibited a high rate of wear. Fatigue failure due to elevated contact stress led to delamination of the ultra-high-molecular-weight polyethylene and in some cases complete failure of the patellae. The results suggest that suboptimal tracking of the patella in the trochlear groove and tilt of the patella button could have a significant effect on the wear of ultra-high-molecular-weight polyethylene and could lead to implant failure. PMID:28661229

The influence of malalignment and ageing following sterilisation by gamma irradiation in an inert atmosphere on the wear of ultra-high-molecular-weight polyethylene in patellofemoral replacements.

PubMed

Maiti, Raman; Cowie, Raelene M; Fisher, John; Jennings, Louise M

2017-07-01

Complications of patellofemoral arthroplasty often occur soon after implantation and, as well as other factors, can be due to the design of the implant or its surgical positioning. A number of studies have previously considered the wear of ultra-high-molecular-weight polyethylene patellae following suboptimal implantation; however, studies have primarily been carried out under a limited number of degrees of freedom. The aim of this study was to develop a protocol to assess the wear of patellae under a malaligned condition in a six-axis patellofemoral joint simulator. The malalignment protocol hindered the tracking of the patella centrally in the trochlear groove and imparted a constant 5° external rotation (tilt) on the patella button. Following 3 million cycles of wear simulation, this condition had no influence on the wear of ultra-high-molecular-weight polyethylene patellae aged for 4 years compared to well-positioned non-aged implants (p > 0.05). However, under the malaligned condition, ultra-high-molecular-weight polyethylene patellae aged 8-10 years after unpacking (following sterilisation by gamma irradiation in an inert atmosphere) and worn ultra-high-molecular-weight polyethylene components also aged 4 years after unpacking (following the same sterilisation process) exhibited a high rate of wear. Fatigue failure due to elevated contact stress led to delamination of the ultra-high-molecular-weight polyethylene and in some cases complete failure of the patellae. The results suggest that suboptimal tracking of the patella in the trochlear groove and tilt of the patella button could have a significant effect on the wear of ultra-high-molecular-weight polyethylene and could lead to implant failure.

Transverse Stress Fracture of the Proximal Patella

PubMed Central

Atsumi, Satoru; Arai, Yuji; Kato, Ko; Nishimura, Akinobu; Nakazora, Shigeto; Nakagawa, Shuji; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Sudo, Akihiro; Kubo, Toshikazu

2016-01-01

Abstract Among stress fractures associated with sports activities, patellar stress fracture is rare. Regarding patella stress fractures, so far only distal transverse or lateral longitudinal fractures have been reported, but there are no reports of transverse fractures occurring in the proximal patella. We describe an extremely rare case of transverse stress fracture of proximal patella in a 9-year-old athlete. A 9-year old boy, who participated in sports (sprints and Kendo) presented with left knee pain without any external injury. In plain radiographs, a fracture line was observed in the proximal 1/3 of the left patella, and a patella stress fracture was diagnosed. For treatment, because 7 months of conservative therapy showed no improvement, internal fixation was carried out using Acutrak screws, and bone union was thus achieved. Three months after the operation, he was able to return to his previous level of athletic sports activity. Regarding the mechanism of onset, it is believed that the causes are longitudinal traction force and patellofemoral contact pressure. On the other hand, the contact region of the patella with the femur changes with the flexion angle of the knee. In the current case, the fracture occurred at a site where the patella was in contact with the femur at a flexion angle of >90°, so it is believed that it occurred as a clinical condition from being subjected to repeated longitudinal traction force and patellofemoral contact pressure at a flexion angle of >90°, during the sports activities of sprints and Kendo. The nonunion of the transverse stress fracture of his proximal patella was successfully treated with internal fixation using Acutrak screws. PMID:26871789

Low Profile Mesh Plating for Patella Fractures: Video of a Novel Surgical Technique.

PubMed

Verbeek, Diederik O; Hickerson, Lindsay E; Warner, Stephen J; Helfet, David L; Lorich, Dean G

2016-08-01

Patella fractures can be challenging to treat particularly in the presence of inferior pole comminution. In this video we present a novel surgical technique for the treatment of patella fractures using a small fragment low profile mesh plate. Key points are the surgical exposure with direct visualization of the articular reduction, the preparation of the mesh plate to accommodate patellar anatomy and the augmentation of the construct using Krackow sutures to address inferior pole comminution. Low profile mesh plating allows for multiplanar fixation of patella fractures while avoiding implant and fixation problems related to tension band fixation. Our early experience with this technique is encouraging and it appears that this technique is useful for the treatment of the majority of patella fractures.

Patella resurfacing during total knee arthroplasty: have we got the issue covered?

PubMed

Sandiford, Nemandra A; Alao, Uthman; Salamut, Wazirl; Weitzel, Stefan; Skinner, J A

2014-12-01

Management of the patella during total knee arthroplasty (TKA) is controversial. Multiple studies have examined mechanical and clinical results of TKA with native and resurfaced patellae with no clear consensus. We surveyed a large cohort of consultant surgeons in a questionnaire based study in order to assess the indications for patella resurfacing and to correlate practice with degree of specialization, experience and volume of procedures performed. Six hundred and nineteen surgeons were included. The main indication for patella resurfacing was patellofemoral arthritis. The ratio of those who always:sometimes:never resurfaced was 1:2:1 irrespective of experience or volume performed. There was no difference between knee specialists and non-specialists (p = 0.977) or between high and lower volume surgeons (p = 0.826). Senior and high volume surgeons tended to always resurface. The majority of surgeons only sometimes resurfaced the patella. The number who always and never resurfaced were similar. There was a tendency for more experienced and high volume surgeons to always resurface.

Patella Resurfacing during Total Knee Arthroplasty: Have We Got the Issue Covered?

PubMed Central

Alao, Uthman; Salamut, Wazirl; Weitzel, Stefan; Skinner, J.A.

2014-01-01

Background Management of the patella during total knee arthroplasty (TKA) is controversial. Multiple studies have examined mechanical and clinical results of TKA with native and resurfaced patellae with no clear consensus. Methods We surveyed a large cohort of consultant surgeons in a questionnaire based study in order to assess the indications for patella resurfacing and to correlate practice with degree of specialization, experience and volume of procedures performed. Results Six hundred and nineteen surgeons were included. The main indication for patella resurfacing was patellofemoral arthritis. The ratio of those who always:sometimes:never resurfaced was 1:2:1 irrespective of experience or volume performed. There was no difference between knee specialists and non-specialists (p = 0.977) or between high and lower volume surgeons (p = 0.826). Senior and high volume surgeons tended to always resurface. Conclusions The majority of surgeons only sometimes resurfaced the patella. The number who always and never resurfaced were similar. There was a tendency for more experienced and high volume surgeons to always resurface. PMID:25436059

Determination of sex from the patella in a contemporary Spanish population.

PubMed

Peckmann, Tanya R; Meek, Susan; Dilkie, Natasha; Rozendaal, Andrew

2016-11-01

The skull and pelvis have been used for the determination of sex for unknown human remains. However, in forensic cases where skeletal remains often exhibit postmortem damage and taphonomic changes the patella may be used for the determination of sex as it is a preservationally favoured bone. The goal of the present research was to derive discriminant function equations from the patella for estimation of sex from a contemporary Spanish population. Six parameters were measured on 106 individuals (55 males and 51 females), ranging in age from 22 to 85 years old, from the Granada Osteological Collection. The statistical analyses showed that all variables were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The overall accuracy of sex classification ranged from 75.2% to 84.8% for the direct method and 75.5%-83.8% for the stepwise method. When the South African White discriminant functions were applied to the Spanish sample they showed high accuracy rates for sexing female patellae (90%-95.9%) and low accuracy rates for sexing male patellae (52.7%-58.2%). When the South African Black discriminant functions were applied to the Spanish sample they showed high accuracy rates for sexing male patellae (90.9%) and low accuracy rates for sexing female patellae (70%-75.5%). The patella was shown to be useful for sex determination in the contemporary Spanish population. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Development and validation of a weight-bearing finite element model for total knee replacement.

PubMed

Woiczinski, M; Steinbrück, A; Weber, P; Müller, P E; Jansson, V; Schröder, Ch

2016-01-01

Total knee arthroplasty (TKA) is a successful procedure for osteoarthritis. However, some patients (19%) do have pain after surgery. A finite element model was developed based on boundary conditions of a knee rig. A 3D-model of an anatomical full leg was generated from magnetic resonance image data and a total knee prosthesis was implanted without patella resurfacing. In the finite element model, a restarting procedure was programmed in order to hold the ground reaction force constant with an adapted quadriceps muscle force during a squat from 20° to 105° of flexion. Knee rig experimental data were used to validate the numerical model in the patellofemoral and femorotibial joint. Furthermore, sensitivity analyses of Young's modulus of the patella cartilage, posterior cruciate ligament (PCL) stiffness, and patella tendon origin were performed. Pearson's correlations for retropatellar contact area, pressure, patella flexion, and femorotibial ap-movement were near to 1. Lowest root mean square error for retropatellar pressure, patella flexion, and femorotibial ap-movement were found for the baseline model setup with Young's modulus of 5 MPa for patella cartilage, a downscaled PCL stiffness of 25% compared to the literature given value and an anatomical origin of the patella tendon. The results of the conducted finite element model are comparable with the experimental results. Therefore, the finite element model developed in this study can be used for further clinical investigations and will help to better understand the clinical aspects after TKA with an unresurfaced patella.

The influence of subchondral vascularisation on chondromalacia patellae.

PubMed

Neusel, E; Graf, J

1996-01-01

An experiment was carried out on 40 rabbits in which the blood supply to the patella was interrupted for periods from 2 weeks to 6 months. With prolonged ischaemia, there were clear changes in the articular cartilage which were comparable with those seen in chondromalacia patellae.

The Association of Health Risk Behaviors and Training-Related Injury Among U.S. Army Basic Trainees

DTIC Science & Technology

2006-04-01

717.7 Chondromalacia Of Patella; Degeneration of articular cartilage of patella 17-MAY-2003 1 719.46 Pain In Joint Involving Lower Leg 19-MAY-2003 I...Thera 7 I Example of diagnoses progression from pain to chondromalacia 18-APR-2003 I 0 1 719.46 Pain In Joint Involving Lower Leg 30-APR-2003· I 717.7... Chondromalacia of Patella; Degeneration of cartilage of patella 30-APR-2003 I V57.1 Other Physical Therapy 28 USACHPPM General Medical Service Study

Telangiectatic osteosarcoma of the patella.

PubMed

Shehadeh, Ahmad M; Haiba, Moutaz A; Henshaw, Robert M; Lack, Ernest

2008-08-01

Although osteosarcoma is the most common primary malignancy of bone, it has only been reported to arise from the patella in a handful of cases. Telangiectatic osteosarcoma accounts for <5% of all osteosarcomas, and it is distinguished histologically by spaces, often blood filled, separated by septa containing highly malignant cells and radiographically by a predominately lytic and/or expansile component. Telangiectatic osteosarcoma can be radiologically confused with aneurysmal bone cyst or giant cell tumor. A 22-year-old otherwise healthy man presented with increasing pain, swelling, and limited flexion of the right knee after failing physical therapy for anterior knee pain. Standard anteroposterior and lateral radiographs demonstrated a diffuse destructive process involving the majority of the patella (including loss of the inferior patellar cortex) and a lytic lesion of the proximal tibia. Apparent osteoid matrix was visible in the soft tissue extension along the inferior pole of the patella. A computed tomography scan of the chest showed 2 pulmonary nodules consistent with metastatic disease. Evaluation of core needle biopsy showed osteosarcoma with telangiectatic features. Given that the majority of the tumor involved the patella/extensor mechanism, it was clear that the tumor originated in the patella. This case presents the first published report of a telangiectatic osteosarcoma arising from the patella.

Structure, ontogeny and evolution of the patellar tendon in emus (Dromaius novaehollandiae) and other palaeognath birds

PubMed Central

Pitsillides, Andrew A.; Hutchinson, John R.

2014-01-01

The patella (kneecap) exhibits multiple evolutionary origins in birds, mammals, and lizards, and is thought to increase the mechanical advantage of the knee extensor muscles. Despite appreciable interest in the specialized anatomy and locomotion of palaeognathous birds (ratites and relatives), the structure, ontogeny and evolution of the patella in these species remains poorly characterized. Within Palaeognathae, the patella has been reported to be either present, absent, or fused with other bones, but it is unclear how much of this variation is real, erroneous or ontogenetic. Clarification of the patella’s form in palaeognaths would provide insight into the early evolution of the patella in birds, in addition to the specialized locomotion of these species. Findings would also provide new character data of use in resolving the controversial evolutionary relationships of palaeognaths. In this study, we examined the gross and histological anatomy of the emu patellar tendon across several age groups from five weeks to 18 months. We combined these results with our observations and those of others regarding the patella in palaeognaths and their outgroups (both extant and extinct), to reconstruct the evolution of the patella in birds. We found no evidence of an ossified patella in emus, but noted its tendon to have a highly unusual morphology comprising large volumes of adipose tissue contained within a collagenous meshwork. The emu patellar tendon also included increasing amounts of a cartilage-like tissue throughout ontogeny. We speculate that the unusual morphology of the patellar tendon in emus results from assimilation of a peri-articular fat pad, and metaplastic formation of cartilage, both potentially as adaptations to increasing tendon load. We corroborate previous observations of a ‘double patella’ in ostriches, but in contrast to some assertions, we find independent (i.e., unfused) ossified patellae in kiwis and tinamous. Our reconstructions suggest a single evolutionary origin of the patella in birds and that the ancestral patella is likely to have been a composite structure comprising a small ossified portion, lost by some species (e.g., emus, moa) but expanded in others (e.g., ostriches). PMID:25551026

Importance of Patella, Quadriceps Forces, and Depthwise Cartilage Structure on Knee Joint Motion and Cartilage Response During Gait.

PubMed

Halonen, K S; Mononen, M E; Jurvelin, J S; Töyräs, J; Klodowski, A; Kulmala, J-P; Korhonen, R K

2016-07-01

In finite-element (FE) models of the knee joint, patella is often omitted. We investigated the importance of patella and quadriceps forces on the knee joint motion by creating an FE model of the subject's knee. In addition, depthwise strains and stresses in patellar cartilage with different tissue properties were determined. An FE model was created from subject's magnetic resonance images. Knee rotations, moments, and translational forces during gait were recorded in a motion laboratory and used as an input for the model. Three material models were implemented into the patellar cartilage: (1) homogeneous model, (2) inhomogeneous (arcadelike fibrils), and (3) random fibrils at the superficial zone, mimicking early stages of osteoarthritis (OA). Implementation of patella and quadriceps forces into the model substantially reduced the internal-external femoral rotations (versus without patella). The simulated rotations in the model with the patella matched the measured rotations at its best. In the inhomogeneous model, maximum principal stresses increased substantially in the middle zone of the cartilage. The early OA model showed increased compressive strains in the superficial and middle zones of the cartilage and decreased stresses and fibril strains especially in the middle zone. The results suggest that patella and quadriceps forces should be included in moment- and force-driven FE knee joint models. The results indicate that the middle zone has a major role in resisting shear forces in the patellar cartilage. Also, early degenerative changes in the collagen network substantially affect the cartilage depthwise response in the patella during walking.

Squamous carcinoma of the lung metastases to the patella.

PubMed

Feng, Helin; Li, Huan; Wang, Jin; Zhang, Xiaoyu; Feng, Jiangang

2015-06-01

We report a case of a 65-year-old man with newly diagnosed squamous carcinoma of the lung, who presented with worsening left-knee pain. A bone scintigraphy displayed an increased radioactivity in the left patella. The patient underwent left patellectomy. Histopathological examination revealed metastasis to the patella from the known lung cancer.

The Position of the Patella and Extensor Mechanism Affects Intraoperative Compartmental Loads During Total Knee Arthroplasty: A Pilot Study Using Intraoperative Sensing to Guide Soft Tissue Balance.

PubMed

Schnaser, Erik; Lee, Yuo-yu; Boettner, Friedrich; Gonzalez Della Valle, Alejandro

2015-08-01

The achievement of a well-balanced total knee arthroplasty is necessary for long-term success. We hypothesize that the dislocation of the patella during surgery affects the distribution of loads in the medial and lateral compartments. Intraoperative load sensors were used to record medial and lateral compartment loads in 56 well-balanced TKAs. Loads were recorded in full extension, relaxed extension, at 45 and 90° of flexion at full gravity-assisted flexion, with the patella in four different positions: dislocated (everted and not), located, and located and secured with two retinacular sutures. The loads in the lateral compartment in flexion were higher with a dislocated patella than with a located patella (P<0.001). A lateralized extensor mechanism artificially increases in the lateral compartment loads in flexion during TKA surgery. Instruments that allow intraoperative soft tissue balance with the patella in a physiologic position are more likely to replicate postoperative compartment loads. II (prospective comparative study). Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Tuberculosis of the patella imitating chronic knee synovitis.

PubMed

Prakash, Jatin; Vijay, Vipul

2014-04-15

Tuberculosis of patella is a rare occurrence with incidence of less than 0.15% in the literature. Owing to its rarity the diagnosis is usually missed. Here we present a case of tuberculosis of the patella, being treated as chronic synovitis elsewhere. An 11-year-old boy presented to us with chronic knee swelling and a draining sinus of 5 months duration. He was being treated with broad spectrum antibiotics and incision and drainage. Standard X-rays revealed a lytic area with surrounding coke such as sequestrum in patella. MRI was suggestive of osteomyelitis of the patella with soft tissue oedema. Diagnosis was confirmed on biopsy. The patient was managed by curettage and excision of the sinus tract along with antitubercular treatment. The patient responded well to antitubercular therapy and gained excellent functional range of movement. In today's era of potent antituberculous drugs and decreasing tuberculosis incidence the rare and unusual locations of tuberculosis such as patella should be borne in mind while dealing with chronic lesions of the knee especially in tubercular endemic areas. A timely diagnosis helps in regaining good range of motion and a satisfactory outcome.

Patella Fractures Prior to Total Knee Arthroplasty: Worse Outcomes but Equivalent Survivorship.

PubMed

Houdek, Matthew T; Shannon, Steven F; Watts, Chad D; Wagner, Eric R; Sems, Stephen A; Sierra, Rafael J

2015-12-01

Distal femur and/or tibial plateau fractures adversely affect outcomes of TKA; however it is unknown if a previous patella fracture affects outcome. We reviewed 113 patients undergoing TKA with a previous patella fracture from 1990 to 2012. Component survival was compared to 19,641 patients undergoing TKA for osteoarthritis during the same period. The 15-year implant survivals following a previous patella fracture was 86%. There was no difference in implant survival compared to patients undergoing TKA for OA (P=0.31). Knee society scores significantly improved following TKA; however patients with a fracture had complications related to knee flexion. Patients undergoing primary TKA following a patella fracture have similar overall revision free survival compared to those undergoing TKA for OA at 15-years. Copyright © 2015 Elsevier Inc. All rights reserved.

[Selective training of the vastus medialis muscle using electrical stimulator for chondromalacia patella].

PubMed

Guo, K; Ye, Q; Lin, J; Shen, J; Yang, X

1996-04-01

Chondromalacia patella is closely related with subluxation and tilt of patella, as well as with muscular atrophy of quadriceps, especially in vastus medialis muscle. 364 cases of chondromalacia patella were treated with selective training of the vastus medialis muscle using electrical stimulator in our hospital. 211 cases were followed up after treatment from 6 months to 3 years. Among them excellent and good results were seen in 130 cases (62%), fair results were seen in 69 cases (33%) and no change was seen in 12 cases (5%). Significant reduction of CA (P < 0.01) and LPA (P < 0.001) were observed in all these patients in comparison with their primary angle. We believe that the selective training of the vastus medialis muscle using electrical stimulator is one of the effective methods for the treatment of chondromalacia patella.

Evolution of the patellar sesamoid bone in mammals

PubMed Central

Samuels, Mark E.; Regnault, Sophie

2017-01-01

The patella is a sesamoid bone located in the major extensor tendon of the knee joint, in the hindlimb of many tetrapods. Although numerous aspects of knee morphology are ancient and conserved among most tetrapods, the evolutionary occurrence of an ossified patella is highly variable. Among extant (crown clade) groups it is found in most birds, most lizards, the monotreme mammals and almost all placental mammals, but it is absent in most marsupial mammals as well as many reptiles. Here, we integrate data from the literature and first-hand studies of fossil and recent skeletal remains to reconstruct the evolution of the mammalian patella. We infer that bony patellae most likely evolved between four and six times in crown group Mammalia: in monotremes, in the extinct multituberculates, in one or more stem-mammal genera outside of therian or eutherian mammals and up to three times in therian mammals. Furthermore, an ossified patella was lost several times in mammals, not including those with absent hindlimbs: once or more in marsupials (with some re-acquisition) and at least once in bats. Our inferences about patellar evolution in mammals are reciprocally informed by the existence of several human genetic conditions in which the patella is either absent or severely reduced. Clearly, development of the patella is under close genomic control, although its responsiveness to its mechanical environment is also important (and perhaps variable among taxa). Where a bony patella is present it plays an important role in hindlimb function, especially in resisting gravity by providing an enhanced lever system for the knee joint. Yet the evolutionary origins, persistence and modifications of a patella in diverse groups with widely varying habits and habitats—from digging to running to aquatic, small or large body sizes, bipeds or quadrupeds—remain complex and perplexing, impeding a conclusive synthesis of form, function, development and genetics across mammalian evolution. This meta-analysis takes an initial step toward such a synthesis by collating available data and elucidating areas of promising future inquiry. PMID:28344905

[Patella navigation in computer-assisted TKA : Intraoperative measurement of patellar kinematics. Video article].

PubMed

Springorum, H-R; Baier, C; Craiovan, B; Maderbacher, G; Renkawitz, T; Grifka, J; Keshmiri, A

2016-07-01

Patellofemoral maltracking is a relevant problem after total knee arthroplasty (TKA). Patella navigation is a tool that allows real time monitoring of patella tracking. This video contribution demonstrates the technique of patellofemoral navigation and a possible consequence of intraoperative monitoring. A higher postoperative lateral tilt is addressed with a widening of the lateral retinaculum in a particular manner. In selected cases of patellofemoral problems, patella navigation is a helpful tool to evaluate patellofemoral tracking intraoperatively. Modifications of implant position and soft tissue measurements can then prevent postoperative patellofemoral maltracking.

No difference in clinical outcome between patella eversion and lateral retraction in total knee arthroplasty: a systemic review and meta-analysis.

PubMed

Zan, Pengfei; Sun, Wei; Yang, Yong; Cai, Xinyu; Ma, Xiaojun; Li, Guodong

2015-06-01

Surgical exposure during total knee arthroplasty (TKA) requires mobilization technique of the patella. Proponents of minimally invasive TKA claim that lateral retraction, rather than eversion, of the patella may be beneficial. Many randomized controlled studies attempt to identify this issue; however, no final conclusion arrives. With this systemic review and meta-analysis, we intended to test whether patella eversion during TKA had deleterious effects. A comprehensive literature search was performed in PubMed, MEDLINE, EMBASE and other internet database. We retrieved all the relevant studies designed to interpret this issue. The searching time frame was from the establishing of these databases until July 2014. Six randomized controlled trials assessing a total of 414 patients and 451 knees were included. The duration of surgery was much shorter (p = 0.003), and the length of skin incision was much longer (p < 0.00001). No significant difference was found on other measurements, including length of hospital stay, quadriceps strength, complications, straight leg raise, Visual Analogue Scale score and functional scores. Patella eversion could decrease the duration of the surgery; nevertheless, the length of skin incision was longer; no significant difference was found on other measurements, especially the quadriceps strength and complications which were concerned. Patella eversion and patella lateral retraction could achieve similar clinical outcomes. Systematic review and meta-analysis, Level I.

Horizontal versus vertical orientation of the loop for tension band wiring of transverse patella fractures.

PubMed

Lee, Sang Ki; Hwang, Yoon Sub; Choy, Won Sik

2014-03-01

Conventional operative treatments of patella fractures are frequently associated with implant failure or displacement. Recent biomechanical studies showed that the orientation of the wire loop and the site of the wire twist can affect the fixation strength. The purpose of this study was to compare the clinical outcome of the tension band technique with loops in different orientations and different knot positions. For this retrospective study, 72 patella fractures (71 patients) were fixed with figure-of-eight configurations in combination with 2 K-wires. Patients were divided into 3 groups according to the orientation of tension band construct. A total of 40 patella fractures were placed with figure-of-eight configurations in a vertical orientation either with 1 wire twist (group 1; 16 patella fractures) or with 2 wire twists at the adjacent corners (group 2; 24 patella fractures). Thirty-two patella fractures were placed with figure-of-eight configurations in a horizontal orientation with 2 wire twists at the adjacent corners (group 3). Range of motion, complication rates, and knee scoring scales (Hospital for Special Surgery and Lysholm) were assessed during serial follow-up. Satisfactory reductions were achieved in all groups, but functional results in the early stage were different. Group 3 had better Hospital for Special Surgery and Lysholm scores at 3 months postoperatively; however, at 6 months and 1 year postoperatively, all groups had similar scores. At the 1-year follow-up, all groups achieved acceptable flexion and range of motion. The overall complication rate was lower in the horizontal group (12.5%). Placing the figure-of-eight tension band construct in a horizontal orientation can provide functional benefits in the early stage after patella fractures. Copyright 2014, SLACK Incorporated.

Associations between measures of adiposity over 10 years and patella cartilage in population-based asymptomatic women.

PubMed

Gunardi, A J; Brennan, S L; Wang, Y; Cicuttini, F M; Pasco, J A; Kotowicz, M A; Nicholson, G C; Wluka, A E

2013-12-01

Osteoarthritis (OA) most commonly affects the patellofemoral compartment of the knee, and is a major cause of pain and disability. Structural changes that evolve prior to the onset of symptoms can be visualised using magnetic resonance imaging (MRI). There is little known information about the role of adiposity on the early structural changes in the patella cartilage in younger, asymptomatic adult females. One hundred and sixty asymptomatic women (20-49 years) participating in the Geelong Osteoporosis Study underwent knee MRI (2006-8). Weight and body mass index (BMI) were measured 10 years prior (1994-7, baseline) and at the time of MRI (current), with change over the period calculated (current-baseline). Relationships between measures of adiposity and patella cartilage volume and defects were examined. After adjustment for age and patella bone volume, there was a reduction of 13 ml (95% confidence interval (95% CI), -25.7, -0.55) in patella cartilage volume for every 1 unit increase in current BMI, and a reduction of 27 ml (95% CI -52.6, -1.5) per BMI unit increase over 10 years (P=0.04 for both). No significant association was observed between baseline BMI and patella cartilage volume (P=0.16). Increased baseline and current weight and BMI were associated with increased prevalence of patella cartilage defects (all P<0.001). Adiposity and weight gain during midlife are associated with detrimental structural change at the patella in young to middle-aged healthy non-osteoarthritic women. Maintaining a healthy weight and avoiding weight gain in younger asymptomatic women may be important in the prevention of patellofemoral OA.

Quadriceps Tendon Autograft Medial Patellofemoral Ligament Reconstruction.

PubMed

Fink, Christian; Steensen, Robert; Gföller, Peter; Lawton, Robert

2018-06-01

Critically evaluate the published literature related to quadriceps tendon (QT) medial patellofemoral ligament (MPFL) reconstruction. Hamstring tendon (HT) MPFL reconstruction techniques have been shown to successfully restore patella stability, but complications including patella fracture are reported. Quadriceps tendon (QT) reconstruction techniques with an intact graft pedicle on the patella side have the advantage that patella bone tunnel drilling and fixation are no longer needed, reducing risk of patella fracture. Several QT MPFL reconstruction techniques, including minimally invasive surgical (MIS) approaches, have been published with promising clinical results and fewer complications than with HT techniques. Parallel laboratory studies have shown macroscopic anatomy and biomechanical properties of QT are more similar to native MPFL than hamstring (HS) HT, suggesting QT may more accurately restore native joint kinematics. Quadriceps tendon MPFL reconstruction, via both open and MIS techniques, have promising clinical results and offer valuable alternatives to HS grafts for primary and revision MPFL reconstruction in both children and adults.

The management of the painful bipartite patella: a systematic review.

PubMed

McMahon, Samuel E; LeRoux, Johannes A; Smith, Toby O; Hing, Caroline B

2016-09-01

This study aimed to identify the most effective method for the treatment of the symptomatic bipartite patella. 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. All of the methods provided results ranging from good to excellent, with acceptable complication rates. 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. IV.

Medial Patella Subluxation: Diagnosis and Treatment

PubMed Central

McCarthy, Mark A.; Bollier, Mathew J.

2015-01-01

Medial patella subluxation is a disabling condition typically associated with previous patellofemoral instability surgery. Patients often describe achy pain with painful popping episodes. They often report that the patella shifts laterally, which occurs as the medial subluxed patella dramatically shifts into the trochlear groove during early knee flexion. Physical examination is diagnostic with a positive medial subluxation test. Nonoperative treatment, such as focused physical therapy and patellofemoral stabilizing brace, is often unsuccessful. Primary surgical options include lateral retinacular repair/imbrication or lateral reconstruction. Prevention is key to avoid medial patella subluxation. When considering patellofemoral surgery, important factors include appropriate lateral release indications, consideration of lateral retinacular lengthening vs release, correct MPFL graft placement and tension, and avoiding excessive medialization during tubercle transfer. This review article will analyze patient symptoms, diagnostic exam findings and appropriate treatment options, as well as pearls to avoid this painful clinical entity. PMID:26361441

Reconstruction of a ruptured patellar tendon using ipsilateral semitendinosus and gracilis tendons with preserved distal insertions: two case reports

PubMed Central

2013-01-01

Background Acute patellar tendon ruptures with poor tissue quality. Ruptures that have been neglected are difficult to repair. Several surgical techniques for the repair of the patellar tendon have been reported, however, these techniques remain difficult because of contractures, adhesions, and atrophy of the quadriceps muscle after surgery. Case presentation We report the cases of 2 Japanese patients (Case 1: a 16-year-old male and Case 2: a 43-year-old male) with patellar tendon ruptures who were treated by reconstruction using semitendinosus-gracilis (STG) tendons with preserved distal insertions. Retaining the original insertion of the STG appears to preserve its viability and provide the revascularization necessary to accelerate healing. Both tendons were placed in front of the patella, in a figure-of-eight fashion, providing stability to the patella. Conclusion Both patients recovered near normal strength and stability of the patellar tendon as well as restoration of function after the operation. PMID:24010848

Arthroscopic Excision of Bipartite Patella With Preservation of Lateral Retinaculum in an Adolescent Ice Hockey Player.

PubMed

James, Evan W; LaPrade, Christopher M; Chahla, Jorge; Cinque, Mark E; Kennedy, Nicholas I; LaPrade, Robert F

Bipartite patella usually is an asymptomatic anatomical variant. However, in some adolescent athletes, it causes anterior knee pain, resulting in decreased participation and performance. We report the case of a high-level adolescent ice hockey player who underwent successful arthroscopic excision with preservation of the lateral retinaculum of a symptomatic bipartite patella after failed nonoperative treatment. The patient returned to play by 6 weeks, and 31-month subjective follow-up scores showed high satisfaction and good clinical outcomes. For patients with a symptomatic bipartite patella, arthroscopic surgery is a good option for reducing pain and returning the athlete to competition.

Intrarater reliability of measuring the patella position by ultrasonography in weight-bearing condition.

PubMed

Chen, Chia Lin; Lo, Chu Ling; Huang, Kai Chu; Huang, Chen Fu

2017-10-01

[Purpose] The aim of this study was to determine the intrarater reliability of using ultrasonography as a measurement tool to assess the patella position in a weight-bearing condition. [Subjects and Methods] Ten healthy adults participated in this study. Ultrasonography was used to assess the patella position during step down with the loading knee in flexion (0° and 20°). The distance between the patella and lateral condyle was measured to represent the patella position on the condylar groove. Two measurements were obtained on the first day and the day after 1 week by the same investigator. [Results] Excellent intrarater reliability, ranging from 0.83 to 0.93, was shown in both conditions. Standard errors of the measurements were 0.5 mm in the straight knee and 0.7 mm in the knee flexion at 20°. Minimal differences in knee flexion at 0° and knee flexion at 20° were 1.5 mm and 1.9 mm, respectively. [Conclusion] Ultrasonography is a reliable assessment tool for evaluating the positional changes of the patella in weight-bearing activities, and it can be easily used by practitioners in the clinical setting.

A correlative study between prevalence of chondromalacia patellae and sports injury in 4068 students.

PubMed

Zhang, Hui; Kong, Xiang-qing; Cheng, Cong; Liang, Mao-hua

2003-12-01

To study the prevalence of chondromalacia patella among college students and the correlation with sports injury. 354 students from gymnastic department and 429 from nongymnastic department with knee joint pain were selected. 184 students from gymnastic department and 342 from nongymnastic department were checked randomly by a surgeon. 77 patients (37 males, 40 females) from gymnastic department and 119 patients (62 males, 57 females) from nongymnastic department were diagnosed as chondromalacia patellae. The amount of exercise and the occurrence of sports injury were investigated in each student. All data were analyzed with SPSS 10.0 statistical software. The prevalence of chondromalacia patella was 20.1% in female students and 11.6% in male students from gymnastic department, and 5.61% in female students and 4.92% in male students from nongymnastic department. The amount of exercise and the occurrence of sports injury to the knee joint in students from gymnastic department were greater than those from nongymnastic department. In both female and male students, the prevalence of chondromalacia patella is higher in gymnastic department than nongymnastic department. Sports injury is an important cause of chondromalacia patella.

Does Patellar Eversion in Total Knee Arthroplasty Cause Patella Baja?

PubMed Central

Sharma, Vineet; Tsailas, Panagiotis G.; Maheshwari, Aditya V.; Ranawat, Chitranjan S.

2008-01-01

Several proponents of minimally invasive surgery-total knee arthroplasty (MIS-TKA) have suggested patellar eversion during a standard exposure of the knee may cause shortening of the patellar tendon and poorer outcomes secondary to acquired patella baja. To explore this suggestion, we retrospectively reviewed 135 consecutive TKAs in 110 patients to ascertain the effect of TKA on the postoperative Insall-Salvati ratio. All surgeries were performed using standard TKA techniques with a midline incision, medial parapatellar arthrotomy, partial excision of the fat pad, and routine eversion of the patella. One patient developed a postoperative patella baja, defined as an Insall-Salvati ratio of less than 0.8. The Knee Society score for knee and function in this patient was 75 and 70, respectively. Five additional patients had a decrease in Insall-Salvati ratio by 10% or more but without patella baja. Mean Knee Society score for knee and function in these five patients was 94 (range, 73–99) and 96 (range, 90–100), respectively, as compared with 93 (range, 37–99) and 94 (range, 40–100) in the remaining 104 patients. Our data suggest the incidence of patella baja is low after TKA despite routine patellar eversion. Furthermore, a 10% or more decrease in the Insall-Salvati ratio without patella baja was not associated with a worse clinical outcome. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18568378

On the development of the patella.

PubMed

Eyal, Shai; Blitz, Einat; Shwartz, Yulia; Akiyama, Haruhiko; Schweitzer, Ronen; Zelzer, Elazar

2015-05-15

The current view of skeletal patterning fails to explain the formation of sesamoid bones. These small bones, which facilitate musculoskeletal function, are exceptionally embedded within tendons. Although their structural design has long puzzled researchers, only a limited model for sesamoid bone development has emerged. To date, sesamoids are thought to develop inside tendons in response to mechanical signals from the attaching muscles. However, this widely accepted model has lacked substantiation. Here, we show that, contrary to the current view, in the mouse embryo the patella initially develops as a bony process at the anteriodistal surface of the femur. Later, the patella is separated from the femur by a joint formation process that is regulated by mechanical load. Concurrently, the patella becomes superficially embedded within the quadriceps tendon. At the cellular level, we show that, similar to bone eminences, the patella is formed secondarily by a distinct pool of Sox9- and Scx-positive progenitor cells. Finally, we show that TGFβ signaling is necessary for the specification of patella progenitors, whereas the BMP4 pathway is required for their differentiation. These findings establish an alternative model for patella development and provide the mechanical and molecular mechanisms that underlie this process. More broadly, our finding that activation of a joint formation program can be used to switch between the formation of bony processes and of new auxiliary bones provides a new perspective on plasticity during skeletal patterning and evolution. © 2015. Published by The Company of Biologists Ltd.

The influence of kinematic conditions and design on the wear of patella-femoral replacements

PubMed Central

Maiti, Raman; Fisher, John; Rowley, Liam

2014-01-01

The success rate of patella-femoral arthroplasty varies between 44% and 90% in 17 years of follow-up. Several studies have been performed previously for assessing the surface wear in the patella-femoral joint. However, they have not included all six degrees of freedom. The aim of this study was to develop a six-axis patella-femoral joint simulator to assess the wear rate for two patellae designs (round and oval dome) at different kinematic conditions. An increase in patellar rotation from 1° to 4° led to a significantly (p<0.049) increased wear rate of round dome from 8.6 mm3/million cycles to 12.3 mm3/million cycles. The wear rate for oval dome increased from 6.3 mm3/million cycles to 14.5 mm3/million cycles. However, the increase was nonsignificant (p>0.08). The increase in wear rate was likely due to the higher cross shear. A decrease in patellar medial lateral displacement from passive to constrained resulted in a nonsignificant reduction in wear (p>0.06). There was no significant difference in wear rate between the two patellae designs (p>0.28). The volumetric wear under all conditions was positively correlated with the level of passive patellar tilt (rho>0.8). This is the first report of preclinical wear simulation of patella-femoral joint in a six-axis simulator under different kinematic conditions. PMID:24477888

Patella Tendon Injuries Secondary to Cement Spacers Used at First-Stage Revision of Infected Total Knee Replacement

PubMed Central

Wilson, Katherine; Kothwal, Rahul; Khan, Wasim S.; Williams, Rhodri; Morgan-Jones, Rhidian

2015-01-01

We describe a series of three patients who sustained patella tendon injuries in infected total knee arthroplasties following the use of a static cement spacer at first-stage knee revision. The patella tendon injuries resulted in significant compromise to wound healing and knee stability requiring multiple surgeries. The mid-term function was poor with an Oxford score at 24 months ranging from 12 to 20. Based on our experience, we advise caution in the use of static cement spacer blocks. If they are to be used, we recommend that they should be keyed in the bone to prevent patella tendon injuries. PMID:25905106

Computational Modelling of Patella Femoral Kinematics During Gait Cycle and Experimental Validation

NASA Astrophysics Data System (ADS)

Maiti, Raman

2016-06-01

The effect of loading and boundary conditions on patellar mechanics is significant due to the complications arising in patella femoral joints during total knee replacements. To understand the patellar mechanics with respect to loading and motion, a computational model representing the patella femoral joint was developed and validated against experimental results. The computational model was created in IDEAS NX and simulated in MSC ADAMS/VIEW software. The results obtained in the form of internal external rotations and anterior posterior displacements for a new and experimentally simulated specimen for patella femoral joint under standard gait condition were compared with experimental measurements performed on the Leeds ProSim knee simulator. A good overall agreement between the computational prediction and the experimental data was obtained for patella femoral kinematics. Good agreement between the model and the past studies was observed when the ligament load was removed and the medial lateral displacement was constrained. The model is sensitive to ±5 % change in kinematics, frictional, force and stiffness coefficients and insensitive to time step.

Computational Modelling of Patella Femoral Kinematics During Gait Cycle and Experimental Validation

NASA Astrophysics Data System (ADS)

Maiti, Raman

2018-06-01

The effect of loading and boundary conditions on patellar mechanics is significant due to the complications arising in patella femoral joints during total knee replacements. To understand the patellar mechanics with respect to loading and motion, a computational model representing the patella femoral joint was developed and validated against experimental results. The computational model was created in IDEAS NX and simulated in MSC ADAMS/VIEW software. The results obtained in the form of internal external rotations and anterior posterior displacements for a new and experimentally simulated specimen for patella femoral joint under standard gait condition were compared with experimental measurements performed on the Leeds ProSim knee simulator. A good overall agreement between the computational prediction and the experimental data was obtained for patella femoral kinematics. Good agreement between the model and the past studies was observed when the ligament load was removed and the medial lateral displacement was constrained. The model is sensitive to ±5 % change in kinematics, frictional, force and stiffness coefficients and insensitive to time step.

Anterior knee pain following total knee replacement correlates with the OARSI score of the cartilage of the patella.

PubMed

Metsna, Vahur; Vorobjov, Sigrid; Lepik, Katrin; Märtson, Aare

2014-08-01

Attempts to relate patellar cartilage involvement to anterior knee pain (AKP) have yielded conflicting results. We determined whether the condition of the cartilage of the patella at the time of knee replacement, as assessed by the OARSI score, correlates with postsurgical AKP. We prospectively studied 100 patients undergoing knee arthroplasty. At surgery, we photographed and biopsied the articular surface of the patella, leaving the patella unresurfaced. Following determination of the microscopic grade of the patellar cartilage lesion and the stage by analyzing the intraoperative photographs, we calculated the OARSI score. We interviewed the patients 1 year after knee arthroplasty using the HSS patella score for diagnosis of AKP. 57 of 95 patients examined had AKP. The average OARSI score of painless patients was 13 (6-20) and that of patients with AKP was 15 (6-20) (p = 0.04). Patients with OARSI scores of 13-24 had 50% higher risk of AKP (prevalence ratio = 1.5, 95% CI: 1.0-2.3) than patients with OARSI scores of 0-12. The depth and extent of the cartilage lesion of the knee-cap should be considered when deciding between the various options for treatment of the patella during knee replacement.

Two Patients with Osteochondral Injury of the Weight-Bearing Portion of the Lateral Femoral Condyle Associated with Lateral Dislocation of the Patella

PubMed Central

Inoue, Hiroaki; Atsumi, Satoru; Ichimaru, Shohei; Fujiwara, Hiroyoshi; Kubo, Toshikazu

2014-01-01

Complications of patellar dislocation include osteochondral injury of the lateral femoral condyle and patella. Most cases of osteochondral injury occur in the anterior region, which is the non-weight-bearing portion of the lateral femoral condyle. We describe two patients with osteochondral injury of the weight-bearing surface of the lateral femoral condyle associated with lateral dislocation of the patella. The patients were 18- and 11-year-old females. Osteochondral injury occurred on the weight-bearing surface distal to the lateral femoral condyle. The presence of a free osteochondral fragment and osteochondral injury of the lateral femoral condyle was confirmed on MRI and reconstruction CT scan. Treatment consisted of osteochondral fragment fixation or microfracture, as well as patellar stabilization. Osteochondral injury was present in the weight-bearing portion of the lateral femoral condyle in both patients, suggesting that the injury was caused by friction between the patella and lateral femoral condyle when the patella was dislocated or reduced at about 90° flexion of the knee joint. These findings indicate that patellar dislocation may occur and osteochondral injury may extend to the weight-bearing portion of the femur even in deep flexion, when the patella is stabilized on the bones of the femoral groove. PMID:25506015

Separate vertical wiring for the fixation of comminuted fractures of the inferior pole of the patella.

PubMed

Song, Hyung Keun; Yoo, Je Hyun; Byun, Young Soo; Yang, Kyu Hyun

2014-05-01

Among patients over 50 years of age, separate vertical wiring alone may be insufficient for fixation of fractures of the inferior pole of the patella. Therefore, mechanical and clinical studies were performed in patients over the age of 50 to test the strength of augmentation of separate vertical wiring with cerclage wire (i.e., combined technique). Multiple osteotomies were performed to create four-part fractures in the inferior poles of eight pairs of cadaveric patellae. One patella from each pair was fixed with the separate wiring technique, while the other patella was fixed with a combined technique. The ultimate load to failure and stiffness of the fixation were subsequently measured. In a clinical study of 21 patients (average age of 64 years), comminuted fractures of the inferior pole of the patellae were treated using the combined technique. Operative parameters were recorded from which post-operative outcomes were evaluated. For cadaveric patellae, whose mean age was 69 years, the mean ultimate loads to failure for the separate vertical wiring technique and the combined technique were 216.4±72.4 N and 324.9±50.6 N, respectively (p=0.012). The mean stiffness for the separate vertical wiring technique and the combined technique was 241.1±68.5 N/mm and 340.8±45.3 N/mm, respectively (p=0.012). In the clinical study, the mean clinical score at final follow-up was 28.1 points. Augmentation of separate vertical wiring with cerclage wire provides enough strength for protected early exercise of the knee joint and uneventful healing.

Fixed-angle plates in patella fractures - a pilot cadaver study

PubMed Central

2011-01-01

Objective Modified anterior tension wiring with K-wires and cannulated lag screws with anterior tension wiring are currently the fixation of choice for patellar fractures. Failure of fixation, migration of the wires, postoperative pain and resulting revision surgery, however, are not uncommon. After preliminary biomechanical testing of a new fixed-angle plate system especially designed for fixation of patella fractures the aim of this study was to evaluate the surgical and anatomical feasibility of implanting such a plate-device at the human patella. Methods In six fresh unfixed female cadavers without history of previous fractures around the knee (average age 88.8 years) a bilateral fixed-angle plate fixation of the patella was carried out after previous placement of a transverse central osteotomy. Operative time, intra-operative problems, degree of retropatellar arthritis (following Outerbridge), quality of reduction and existence of any intraarticular screw placement have been raised. In addition, lateral and anteroposterior radiographs of all specimens were made. Results Due to the high average age of 88.8 years no patella showed an unimpaired retropatellar articular surface and all were severely osteoporotic, which made a secure fixation of the reduction forceps during surgery difficult. The operation time averaged 49 minutes (range: 36-65). Although in postoperative X-rays the fracture gap between the fragments was still visible, the analysis of the retropatellar surface showed no residual articular step or dehiscence > 0.5 mm. Also in a total of 24 inserted screws not one intraarticular malposition was found. No intraoperative complications were noticed. Conclusions Osteosynthesis of a medial third patella fracture with a bilateral fixed-angle plate-device is surgically and anatomically feasible without difficulties. Further studies have to depict whether the bilateral fixed-angle plate-osteosynthesis of the patella displays advantages over the established operative procedures. PMID:21345769

Can turned inward patella predict an excess of femoral anteversion during gait in spastic diplegic children?

PubMed

Simon, Anne-Laure; Presedo, Ana; Ilharreborde, Brice; Mallet, Cindy; Mazda, Keyvan; Penneçot, Georges-François

2014-06-01

Determining patellar orientation in the transverse plane during observational gait analysis is a fundamental aspect of physical examinations. Many physicians consider that an abnormal position of the patella in the transverse planes is only explained by a rotational abnormality of the proximal femur. A total of 188 spastic diplegic children with cerebral palsy were reviewed (376 lower limbs). The physical examination included observation of patellar orientation at midstride and measuring femoral anteversion (FA). All patients also underwent 3-dimensional (3D) computerized gait analysis of pelvic and hip rotation kinematics. Observational gait analysis and videotapes found 103 children (206 lower limbs) with inturned patella at midstance. Kinematic data from 3D gait analysis showed that the visual impression of turned inward patella was erroneous in 48 limbs. Of the remaining 158 lower limbs, 117 (74%) exhibited excessive FA and 41 (26%) did not. Of the 117 with excessive FA, kinematics showed only 66 (56%) with excessive internal hip rotation (with or without excessive internal pelvic rotation). Of the 41 lower limbs without excessive FA, 25 were explained by excessive internal pelvic rotation and 16 were explained by excessive internal hip rotation (isolated spasticity and/or contracture of internal rotator muscles). Turned inward patella was caused by isolated excessive internal pelvic rotation in 48%, excessive internal hip rotation in 35% (including 44 cases with excessive FA and 12 cases with isolated spasticity and/or contracture of internal hip rotators), and excessive internal hip rotation combined with excessive internal pelvic rotation in 17%. Excessive FA was not the only cause of turned inward patella gait and could not explain this gait anomaly by itself. Excessive internal pelvic rotation was the most frequent cause of turned inward patella gait. Level IV.

Separate Vertical Wiring for the Fixation of Comminuted Fractures of the Inferior Pole of the Patella

PubMed Central

Song, Hyung Keun; Yoo, Je Hyun; Byun, Young Soo

2014-01-01

Purpose Among patients over 50 years of age, separate vertical wiring alone may be insufficient for fixation of fractures of the inferior pole of the patella. Therefore, mechanical and clinical studies were performed in patients over the age of 50 to test the strength of augmentation of separate vertical wiring with cerclage wire (i.e., combined technique). Materials and Methods Multiple osteotomies were performed to create four-part fractures in the inferior poles of eight pairs of cadaveric patellae. One patella from each pair was fixed with the separate wiring technique, while the other patella was fixed with a combined technique. The ultimate load to failure and stiffness of the fixation were subsequently measured. In a clinical study of 21 patients (average age of 64 years), comminuted fractures of the inferior pole of the patellae were treated using the combined technique. Operative parameters were recorded from which post-operative outcomes were evaluated. Results For cadaveric patellae, whose mean age was 69 years, the mean ultimate loads to failure for the separate vertical wiring technique and the combined technique were 216.4±72.4 N and 324.9±50.6 N, respectively (p=0.012). The mean stiffness for the separate vertical wiring technique and the combined technique was 241.1±68.5 N/mm and 340.8±45.3 N/mm, respectively (p=0.012). In the clinical study, the mean clinical score at final follow-up was 28.1 points. Conclusion Augmentation of separate vertical wiring with cerclage wire provides enough strength for protected early exercise of the knee joint and uneventful healing. PMID:24719149

Muscle-Tendon Unit Properties during Eccentric Exercise Correlate with the Creatine Kinase Response

PubMed Central

Hicks, Kirsty M.; Onambele-Pearson, Gladys L.; Winwood, Keith; Morse, Christopher I.

2017-01-01

Aim: The aim of this paper was to determine whether; (1) patella tendon stiffness, (2) the magnitude of vastus lateralis fascicle lengthening, and (3) eccentric torque correlate with markers of exercise induced muscle damage. Method: Combining dynamometry and ultrasonography, patella tendon properties and vastus lateralis architectural properties were measured pre and during the first of six sets of 12 maximal voluntary eccentric knee extensions. Maximal isometric torque loss and creatine kinase activity were measured pre-damage (−48 h), 48, 96, and 168 h post-damage as markers of exercise-induced muscle damage. Results: A significant increase in creatine kinase (883 ± 667 UL) and a significant reduction in maximal isometric torque loss (21%) was reported post-eccentric contractions. Change in creatine kinase from pre to peak significantly correlated with the relative change in vastus lateralis fascicle length during eccentric contractions (r = 0.53, p = 0.02) and with eccentric torque (r = 0.50, p = 0.02). Additionally, creatine kinase tended to correlate with estimated patella tendon lengthening during eccentric contractions (p < 0.10). However, creatine kinase did not correlate with resting measures of patella tendon properties or vastus lateralis properties. Similarly, torque loss did not correlate with any patella tendon or vastus lateralis properties at rest or during eccentric contractions. Conclusion: The current study demonstrates that the extent of fascicle strain during eccentric contractions correlates with the magnitude of the creatine kinase response. Although at rest, there is no relationship between patella tendon properties and markers of muscle damage; during eccentric contractions however, the patella tendon may play a role in the creatine kinase response following EIMD. PMID:28974931

Spontaneous bilateral fracture of patella.

PubMed

Moretti, Biagio; Speciale, Domenico; Garofalo, Raffaele; Moretti, Lorenzo; Patella, Silvio; Patella, Vittorio

2008-03-01

Bilateral patellae fractures represent a rare entity, accounting for approximately 2.9% of all lesions interesting in this anatomical district. In most cases found in the published work, they are described as stress fractures or as complications of chronic diseases such as osteoporosis, renal failure and secondary hyperparathyroidism. Although many pathogenetic mechanisms have been supposed, none have been proved for certain. Insufficiency fractures of the patellae are rare events and no data has been published on their incidence. We present a case of bilateral fracture of the patellae due to an indirect trauma occurring in an 85-year-old patient affected by Parkinson's disease, osteoporosis and diffuse degenerative osteoarthritis. X-ray of the knees (anteroposterior and lateral) and magnetic resonance imaging evaluation confirmed the fractures. The patient was treated conservatively. She had a good result, returning to her previous autonomous ambulation. This case is unusual because there was no direct trauma to the knees because of bilaterality, but confirmed previous observations about insufficiency fractures of patellae in the presence of comorbidity. Insufficiency fractures of patellae can be an insidious condition in elderly people. Prepatellar pain, a common symptom in the relapse phase of degenerative arthritis of the knee, should not be underestimated, particularly in patients with diseases influencing metabolism of bone and with an elevated risk of fall. A periodical clinical and instrumental follow up should be done in these patient. Moreover, we underline the necessity of a multidisciplinary approach.

Determining gender by taking measurements from magnetic resonance images of the patella.

PubMed

Yasar Teke, Hacer; Ünlütürk, Özge; Günaydin, Elif; Duran, Semra; Özsoy, Sait

2018-05-08

A key step in making a positive identification in forensic medicine is the establishment of a biological profile, which involves determining factors such as gender, age, ancestry, and stature. The goal of this study was to determine if gender could be established by taking various measurements of the patella taken from magnetic resonance imaging (MRI) images and analyzing the variations by gender. The sample group consisted of 220 patients (110 male and 110 female) whose patella were measured using MRI images of their left knee. Reasons for exclusion were any previous surgery, patella bipartite variation, any fracture in the patella due to trauma or findings of mass or infection. Three measurements - transverse length (TP), craniocaudal length (CC) and anteroposterior length (APP) - were taken off T2-weighted axial and sagittal MRI scans. The program SPSS (Version 21.0) was used to make a descriptive analysis, independent t-test and discriminative analysis. It was found possible to determine gender with an accuracy rate of 91% for females and 87% for males. Since measurements were made individually the accuracy for gender estimation is lower than that seen in other methods. The findings are important in that they show that it is possible to determine gender with a high degree of accuracy using just a few measurements taken from the patella. Copyright © 2018 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Runners knee (image)

MedlinePlus

... forces on the knee, such as a misaligned patella. Chondromalacia is treated with rest or immobilization and ... is a problem with the alignment of the patella that cannot be corrected with therapy.

Patellar Shape-Memory Fixator for the Treatment of Comminuted Fractures of the Inferior Pole of the Patella

NASA Astrophysics Data System (ADS)

Liu, Xin-Wei; Shang, Hui-Juan; Xu, Shuo-Gui; Wang, Zhi-Wei; Zhang, Chun-Cai; Fu, Qing-Ge

2011-07-01

Comminuted and displaced fractures of the inferior pole of the patella are not easy to reduce and it is difficult to fix the fragments soundly enough to allow early movement of the knee. The purpose of this study is to evaluate the clinical effectiveness of the internal fixation technique with Patellar Shape-Memory Fixator (PSMF) in acute comminuted fractures of the inferior pole of the patella. We retrospectively studied 25 patients with comminuted fractures of the inferior pole of the patella who were treated with PSMF and followed up for a mean period of 26 months (14 to 60). All the fractures healed at a mean of 6 weeks (5 to 7). The mean grading at the final follow-up was 29.5 points (27 to 30) using the Bostman score, with no observable restriction of movement. No breakage of the PSMF or infection occurred. No delayed union, nonunion, and infection were seen. This technique preserved the length of the patella, reduced the comminuted fragments of the inferior pole and avoided long-term immobilization of the knee.

Spontaneous patella fracture associated with anterior tibial tubercle pseudarthrosis in a revised knee replacement following knee Arthrodesis

PubMed Central

2013-01-01

Background Conversion of a knee arthrodesis to a Total Knee Arthroplasty is an uncommon procedure. Revision Total Knee Arthroplasty in this setting presents the surgeon with a number of challenges including the management of the extensor mechanism and patella. Case presentation We describe a unique case of a 69 years old Caucasian man who underwent a revision Total Knee Arthroplasty using a tibial tubercle osteotomy after a previous conversion of a knee arthrodesis without patella resurfacing. Unfortunately 9 months following surgery a tibial tubercle pseudarthrosis and spontaneous patella fracture occurred. Both were managed with open reduction and internal fixation. At 30 months follow-up the tibial tubercle osteotomy had completely consolidated while the patella fracture was still evident but with no signs of further displacement. The patient was completely satisfied with the outcome and had a painless range of knee flexion between 0-95°. Conclusions We believe that patients undergoing this type of surgery require careful counseling regarding the risk of complications both during and after surgery despite strong evidence supporting improved functional outcomes. PMID:24195600

Outcome of low profile mesh plate in management of comminuted displaced fracture patella.

PubMed

Singer, Mohamed S; Halawa, Abdelsamie M; Adawy, Adel

2017-06-01

To assess the clinical results of using mesh plate in management of displaced comminuted fracture patella. Between January 2014 and October 2015, nine patients with closed displaced comminuted fracture patella were fixed using mesh plate and 2mm mini screws. All fractures united after an average of 10 weeks. At final follow-up of an average 19.6 months, average postoperative Lysholm score was 89.1±4.9, and average Postoperative Böstman scale was 27.2±3.1. No hardware related complications were recorded. Low profile mesh plate is a good option in management of comminuted fracture patella with good clinical outcome. This new surgical technique may be particularly useful in comminuted fractures when patellectomy would otherwise be considered. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Chronic chondromalacia of the patella: comparison of morphological (magnetic resonance) and functional findings (isokinetic parameters) after rehabilitation].

PubMed

Felicetti, G; Avanza, F; Fiori, M; Brignoli, E; Rovescala, R

1996-01-01

The knee is a common site for injuries of the cartilage, capsule and ligament, which calls for the use of noninvasive techniques to assess injury severity properly and to plan adequate rehabilitation. Our study was aimed at comparing MR with isokinetic findings. To this purpose, 40 patients were examined; they were all affected with chondromalacia patellae, grades I-III, previously diagnosed at arthroscopy. Namely, 8 patients had grade I and 32 grades II and III chondromalacia. After MR and isokinetic exams, all patients were submitted to a standardized rehabilitation program. Our results indicate a marked decrease in quadriceps strength, especially in the most severe cases; in less severe cases, recovery was complete at 6 months, while the deficit remained in grades II and III injuries. MR yield was not relevant in 4 of 8 cases, while isokinetic findings were negative in one case. Both methods were positive in the most severe cases. At 6 months, both functional and MR findings were normal in grade I injuries, while some alterations remained in the others.

Do centimetres matter? Self-reported versus estimated height measurements in parents.

PubMed

Gozzi, T; Flück, Ce; L'allemand, D; Dattani, M T; Hindmarsh, P C; Mullis, P E

2010-04-01

An impressive discrepancy between reported and measured parental height is often observed. The aims of this study were: (a) to assess whether there is a significant difference between the reported and measured parental height; (b) to focus on the reported and, thereafter, measured height of the partner; (c) to analyse its impact on the calculated target height range. A total of 1542 individual parents were enrolled. The parents were subdivided into three groups: normal height (3-97th Centile), short (<3%) and tall (>97%) stature. Overall, compared with men, women were far better in estimating their own height (p < 0.001). Where both partners were of normal, short or tall stature, the estimated heights of their partner were quite accurate. Women of normal stature underestimated the short partner and overestimated the tall partner, whereas male partners of normal stature overestimated both their short as well as tall partners. Women of tall stature estimated the heights of their short partners correctly, whereas heights of normal statured men were underestimated. On the other hand, tall men overestimated the heights of their female partners who are of normal and short stature. Furthermore, women of short stature estimated the partners of normal stature adequately, and the heights of their tall partners were overestimated. Interestingly, the short men significantly underestimated the normal, but overestimated tall female partners. Only measured heights should be used to perform accurate evaluations of height, particularly when diagnostic tests or treatment interventions are contemplated. For clinical trails, we suggest that only quality measured parental heights are acceptable, as the errors incurred in estimates may enhance/conceal true treatment effects.

Is Electrocautery of Patella Useful in Patella Non-Resurfacing Total Knee Arthroplasty?: A Prospective Randomized Controlled Study.

PubMed

Kwon, Sae Kwang; Nguku, Levis; Han, Chang Dong; Koh, Yong-Gon; Kim, Dong-Wook; Park, Kwan Kyu

2015-12-01

There is controversy over the need for electrocauterization of the patella in non-resurfacing total knee arthroplasty (TKA). We investigated whether this procedure is beneficial through a prospective randomized controlled trial. Fifty patients who underwent electrocautery were compared with 50 patients who did not undergo this procedure. We determined cartilage status, preoperative and postoperative American Knee Society (AKS) score, the Western Ontario and McMaster Universities score (WOMAC) and the Patellofemoral (PF) scores for a minimum of 5 years. The two groups did not differ significantly in demographics, intraoperative cartilage status, or preoperative or postoperative outcomes. No complications were detected in either group. We found no benefits of electrocautery of the patella in patellar non-resurfacing TKA up to 5 years. Copyright © 2015 Elsevier Inc. All rights reserved.

Fixed-angle plate osteosynthesis of the patella - an alternative to tension wiring?

PubMed

Wild, M; Eichler, C; Thelen, S; Jungbluth, P; Windolf, J; Hakimi, M

2010-05-01

The goal of this study is carry out a biomechanical evaluation of the stability of a bilateral, polyaxial, fixed-angle 2.7 mm plate system specifically designed for use on the patella. The results of this approach are then compared to the two currently most commonly used surgical techniques for patella fractures: modified anterior tension wiring with K-wires and cannulated lag screws with anterior tension wiring. A transient biomechanical analysis determining material failure points of all osteosyntheses were conducted on 21 identical left polyurethane foam patellae, which were osteotomized horizontally. Evaluated were load (N), displacement (mm) and run-time (s) as well as elastic modulus (MPa), tensile strength (MPa) and strain at failure (%). With a maximum load capacity of 2396 (SD 492) N, the fixed-angle plate proved to be significantly stronger than the cannulated lag screws with anterior tension wiring (1015 (SD 246) N) and the modified anterior tension wiring (625 (SD 84.9) N). The fixed-angle plate displayed significantly greater stiffness and lower fracture gap dehiscence than the other osteosyntheses. Additionally, osteosynthesis deformation was found to be lower for the fixed-angle plate. A bilateral fixed-angle plate was the most rigid and stable osteosynthesis for horizontal patella fractures with the least amount of fracture gap dehiscence. Further biomechanical trials performed under cycling loading with fresh cadaver specimen should be done to figure out if a fixed-angle plate may be an alternative in the surgical treatment of patella fractures. Copyright 2009 Elsevier Ltd. All rights reserved.

Multifocal pigmented villonodular synovitis coexisting in both the knee joint and the patella: a case report and literature review.

PubMed

Gao, Mingxuan; Li, Hong; Liang, Xiaoyan; Fu, Xiaoyan; Li, Xusheng

2017-07-06

Pigmented villonodular synovitis (PVNS) is an uncommon entity of proliferative lesion of the synovium, presenting with different clinical signs and symptoms. PVNS rarely forms an osteolytic lesion in a bone. Here we report a unique case of PVNS with a nodular lesion in the left patella. A 37-year-old female was referred to our hospital with complaints of ongoing left knee pain and a painful and palpable mass in her left popliteal fossa. MRI demonstrated a nodular lesion in the left patella, diffuse affected synovial tissue in the left knee and an extra-articular mass in the left popliteal fossa. After a primary diagnosis of PVNS had been established, combined arthroscopic synovectomy and open resection were performed. The postoperative pathological diagnoses of the resected mass from the popliteal fossa, the affected synovial tissue and the lesion in the patella were consistent with PVNS. At 1-year follow-up, no evidence of recurrence was noted. Based on brief literature review of PNVS, we presented a very rare case of PVNS with a nodular lesion in the left patella, diffuse affected synovial tissue in the left knee and an extra-articular mass in the left popliteal fossa.

[The external patello-tibial transfixation (EPTT). Part II: Clinical application and results].

PubMed

Ishaque, B; Gotzen, L; Ziring, E; Petermann, J

1999-07-01

In part I of the paper the biomechanical and technical background of the EPTT using the MPT fixator and the indications for this procedure have been described. In part II we report about the clinical application of the EPTT in 67 patients with a wide spectrum of repairs and reconstructions of the extensor mechanism. 48 patients had fresh injuries, 18 of them with severe concomitant knee lesions and 19 patients had neglected rsp. unsuccessfully operated injuries. There were 4 deep infections, two of them related to the MPT fixator. In the patients with uneventful healing the fixator remained in place for 7.3 weeks in average. The clinical, isokinetic and radiological results were reviewed in 17 patients with an average follow-up time of 37.3 months. There were 5 patients with partial patellectomy and tendon reattachment because of lower patella pole comminution and 12 patients with tendon reattachment ruptured at the inferior patella pole or suture repair in midsubstance rupture. The clinical results according to the IKDC score were rated in 3 patients as normal, in 10 patients as nearly normal and in 4 patients as abnormal. This rating was highly dependend on the subjective judgement by the patients who considered their operated knees not as normal as the contralateral knees. From our clinical experiences and results we can derive that the EPTT enables the surgical management of extensor mechanism disruptions with a minimum of internal fixation material and provides a safe protection of the repairs and reconstructions during the healing period. The EPTT allows immediate unrestricted functional rehabilitation and early walking without crutches. Thus the EPTT represents an effective alternative to the patello-tibial cerclage with a wire or synthetic ligaments.

Association between trochlear morphology and chondromalacia patella: an MRI study.

PubMed

Duran, Semra; Cavusoglu, Mehtap; Kocadal, Onur; Sakman, Bulent

This study aimed to compare trochlear morphology seen in magnetic resonance imaging between patients with chondromalacia patella and age-matched control patients without cartilage lesion. Trochlear morphology was evaluated using the lateral trochlear inclination, medial trochlear inclination, sulcus angle and trochlear angle on the axial magnetic resonance images. Consequently, an association between abnormal trochlear morphology and chondromalacia patella was identified in women. In particular, women with flattened lateral trochlea are at an increased risk of patellar cartilage structural damage. Copyright © 2016 Elsevier Inc. All rights reserved.

Pathological fracture of the patella due to an atypical located aneurysmal bone cyst: verification by means of ultrasound-guided biopsy.

PubMed

Plaikner, Michaela; Gruber, Hannes; Henninger, Benjamin; Gruber, Leonhard; Kosiol, Juana; Loizides, Alexander

2016-03-01

We report on a rare case of an atypical located aneurysmal bone cyst (ABC) in the patella presenting with pathological fracture after trauma. Using all available diagnostic modalities and by means of ultrasound-guided core-needle biopsy an unclear and suspected pathological fractured cystic bone lesion in the patella of a young man could be further clarified. The acquired images suggested the diagnosis of a pathological fractured aneurysmal bone cyst after mild trauma. However, due to the extraordinary location and clinical presentation the diagnosis was secured by means of ultrasound-guided biopsy through a small cortical gap. As shown in this rare case of an atypical aneurysmal bone cyst of the patella, the quite seldom but sometimes possible ultrasound-guided biopsy of intraosseous lesions can help to achieve the diagnostic clarification and should also be taken into account as a non-standard procedure.

Unicameral bone cyst of the patella in a young dog.

PubMed

Petazzoni, M; Briotti, F; Beale, B

2015-01-01

This report describes a case of a solitary unicameral patellar bone cyst in a young dog. A five-month-old, male Dobermann Pinscher dog was referred for a 10-day left hindlimb lameness. A mild swelling of the peripatellar soft tissues of the left patella was detected upon physical examination. Signs of pain were elicited upon direct palpation of the patella. Radiographic examination revealed an oval radiolucency within the medullary cavity at the base of the left patella. Radiographic examination, arthroscopy, and histopathology findings supported the diagnosis of a benign patellar bone cyst. The condition was treated by surgical curettage and autogenous bone graft harvested from the ipsilateral proximal tibia. Clinical signs, including lameness and signs of pain upon deep palpation, disappeared three weeks after surgery. Follow-up re-evaluation five years after surgery revealed no recurrence of the cyst and the patient was asymptomatic.

Patellar metastasis from primary tumor

PubMed Central

Li, Gang; Shan, Changxing; Sun, Ran; Liu, Song; Chen, Song; Song, Mingzhi; Lu, Ming

2018-01-01

Although bone tumors are frequently located in the knee area, primary tumors of the patella are rare and patellar metastases are even rarer. Knee pain is the most common complaint of patients with patellar metastases. Owing to the low incidence of patellar metastases, misdiagnosis is not unusual. The present review analyzes ~44 cases of patellar metastases originating from distinct primary sites. Reports of malignant tumors of the lung and kidney metastasizing to the patella were more common than those of other patellar metastases. Relative incidence, symptomatology, imaging features, histopathology and treatment options for these patellar metastatic lesions are described respectively along with a review of the literature. Despite numerous experiments demonstrating the reasons for implantation of tumor in patella, the answer to this question has not yet been revealed. In the light of the increasing attention on the diagnosis and the treatment of these lesions, the availability of the integrated information regarding metastases in the patella becomes more relevant. PMID:29434829

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

PubMed

Matic, George T; Flanigan, David C

2015-09-01

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. To determine the most effective intervention in returning athletes with symptomatic bipartite patella to their prior activity levels. 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. 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. 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. Copyright © 2015 Elsevier B.V. All rights reserved.

The Effect of Patella Eversion on Clinical Outcome Measures in Simultaneous Bilateral Total Knee Arthroplasty: A Prospective Randomized Controlled Trial.

PubMed

Zan, Pengfei; Wu, Zhong; Yu, Xiao; Fan, Lin; Xu, Tianyang; Li, Guodong

2016-03-01

During total knee arthroplasty (TKA), surgical exposure requires mobilization technique of the patella. With this trial, we intended to investigate the effect of patella eversion on clinical outcome measures in simultaneous bilateral TKA. We prospectively enrolled 44 patients (88 knees) from April 2008 to June 20l4.One knee was operated with patella eversion (group A) and the other with patella lateral retraction (group B) randomly. Follow-up results, including the operation time, complications, and the time of achieving straight leg raise (SLR) and 90° knee flexion, were recorded. The data of range of motion (ROM) and Visual Analogue Scale score were collected separately at 7 days, 3 months, 6 months, and 1 year postoperatively. The time of achieving SLR was 2.7 ± 0.8 days in group A and 2.1 ± 0.7 DAYS in group B, which were significantly different (P = .032). Significant difference was found on active and passive ROM during the follow-up times between groups A and B, except the passive ROM at 6 months postoperatively. No significant difference was found on operation time, complications, patella baja or tilt, time of achieving 90°knee flexion, and Visual Analogue Scale score during the follow-up times. Patellar eversion was adverse to the early knee function recovery after TKA; it would delay the time of achieving SLR and decrease the passive and active ROM. In addition, more carefully and scientifically designed randomized controlled trials are still required to further prove the claim. Copyright © 2016 Elsevier Inc. All rights reserved.

Quadriceps Weakness, Patella Alta and Structural Features of Patellofemoral Osteoarthritis: The Multicenter Osteoarthritis Study

PubMed Central

Stefanik, Joshua J.; Guermazi, Ali; Zhu, Yanyan; Zumwalt, Ann C.; Gross, K. Douglas; Clancy, Margaret; Lynch, John A.; Segal, Neil A.; Lewis, Cora E.; Roemer, Frank W.; Powers, Christopher M.; Felson, David T.

2011-01-01

Objective To determine the relationship between quadriceps weakness and cartilage damage and bone marrow lesions (BMLs) in the patellofemoral joint (PFJ), and if this relationship is modified by patella alta. Methods The Multicenter Osteoarthritis (MOST) Study is a cohort study of persons aged 50–79 years with or at risk for knee OA. Concentric knee extensor strength was measured using an isokinetic dynamometer. Patella alta was measured using the Insall-Salvati ratio (ISR) on the lateral radiograph, and cartilage damage and bone marrow lesions (BMLs) were graded on MRI in the PFJ. We determined the association between quadriceps weakness with cartilage damage and BMLs in the PFJ among those knees with (ISR≥1.2) and without patella alta (ISR<1.2) using multiple binomial regression. Results 807 knees were studied (mean age 62 years, BMI 30, ISR 1.10), 64% from female subjects. Compared with knees in the highest strength tertile, those in the lowest had 10.2% {95% Confidence Interval (CI) 3–18}, 9.1% (95% CI 2–16), and 7.1% (95% CI 1–13) higher prevalence of lateral PFJ cartilage damage, medial PFJ cartilage damage, and lateral PFJ BMLs, respectively. The association between quadriceps weakness with cartilage damage and BMLs was not different between knees with and with out patella alta in the lateral PFJ. Conclusion Quadriceps weakness was associated with PFJ cartilage damage and BMLs. While both patella alta and quadriceps weakness are associated with PFJ damage, the combination of the two was not associated with more damage than either of these factors alone. PMID:21702087

Current concepts of etiology and treatment of chondromalacia patellae.

PubMed

Bentley, G; Dowd, G

1984-10-01

Chondromalacia patellae is a distinct clinical entity characterized by retropatellar pain that is associated with recognizable changes in the articular cartilage of the posterior surface of the patella. Several factors may be involved in the etiology, such as severe patella alta, trauma, and, in rare cases, abnormal patellar tracking. Clinical symptoms and signs are reliable in only 50% of cases, but measurable quadriceps wasting, palpable patellofemoral crepitus, and effusion are strongly suggestive. Diagnosis must be confirmed by arthroscopy or direct examination of the posterior surface of the patella. Radiologic measurements of patellofemoral relations are of limited value in diagnosis. The initial pathologic finding is usually surface cartilage breakdown. Radioisotope studies show cartilage cell replication which suggests a healing capacity in early cases following treatment that alters the load through the affected cartilage. There is no evidence of progression to patellofemoral osteoarthritis, which is probably a different entity. The treatment should be conservative where possible with isometric quadriceps exercises and simple anti-inflammatory drugs such as aspirin. Operative treatment is indicated for patients with persistent pain and macroscopic involvement of more than half a centimeter of the articular cartilage surface. The simplest effective procedure that avoids quadriceps dysfunction and fibrosis is a distal patellar tendon medial realignment with lateral release and medial reefing of the quadriceps expansion. Patellectomy is indicated in more extensive involvement of the patella of 2 or more centimeters in diameter, but this must be performed only when the patient has excellent quadriceps function before surgery and is motivated to exercise after surgery.

An anatomically based patient-specific finite element model of patella articulation: towards a diagnostic tool.

PubMed

Fernandez, J W; Hunter, P J

2005-08-01

A 3D anatomically based patient-specific finite element (FE) model of patello-femoral (PF) articulation is presented to analyse the main features of patella biomechanics, namely, patella tracking (kinematics), quadriceps extensor forces, surface contact and internal patella stresses. The generic geometries are a subset from the model database of the International Union of Physiological Sciences (IUPS) (http://www.physiome.org.nz) Physiome Project with soft tissue derived from the widely used visible human dataset, and the bones digitised from an anatomically accurate physical model with muscle attachment information. The models are customised to patient magnetic resonance images using a variant of free-form deformation, called 'host-mesh' fitting. The continuum was solved using the governing equation of finite elasticity, with the multibody problem coupled through contact mechanics. Additional constraints such as tissue incompressibility are also imposed. Passive material properties are taken from the literature and implemented for deformable tissue with a non-linear micro-structurally based constitutive law. Bone and cartilage are implemented using a 'St-Venant Kirchoff' model suitable for rigid body rotations. The surface fibre directions have been estimated from anatomy images of cadaver muscle dissections and active muscle contraction was based on a steady-state calcium-tension relation. The 3D continuum model of muscle, tendon and bone is compared with experimental results from the literature, and surgical simulations performed to illustrate its clinical assessment capabilities (a Maquet procedure for reducing patella stresses and a vastus lateralis release for a bipartite patella). Finally, the model limitations, issues and future improvements are discussed.

Does Kinematic Alignment and Flexion of a Femoral Component Designed for Mechanical Alignment Reduce the Proximal and Lateral Reach of the Trochlea?

PubMed

Brar, Abheetinder S; Howell, Stephen M; Hull, Maury L; Mahfouz, Mohamed R

2016-08-01

Kinematically aligned total knee arthroplasty uses a femoral component designed for mechanical alignment (MA) and sets the component in more internal, valgus, and flexion rotation than MA. It is unknown how much kinematic alignment (KA) and flexion of the femoral component reduce the proximal and lateral reach of the trochlea; two reductions that could increase the risk of abnormal patella tracking. We simulated MA and KA of the femoral component in 0° of flexion on 20 3-dimensional bone models of normal femurs. The mechanically and kinematically aligned components were then aligned in 5°, 10°, and 15° of flexion and downsized until the flange contacted the anterior femur. The reductions in the proximal and lateral reach from the proximal point of the trochlea of the MA component set in 0° of flexion were computed. KA at 0° of flexion did not reduce the proximal reach and reduced the lateral reach an average of 3 mm. Flexion of the MA and KA femoral component 5°, 10°, and 15° reduced the proximal reach an average of 4 mm, 8 mm, and 12 mm, respectively (0.8 mm/degree of flexion), and reduced the lateral reach an average of 1 mm and 4 mm regardless of the degree of flexion, respectively. Arthroplasty surgeons and biomechanical engineers striving to optimize patella tracking might consider developing surgical techniques to minimize flexion of the femoral component when performing KA and MA total knee arthroplasty to promote early patella engagement and consider designing a femoral component with a trochlea shaped specifically for KA. Copyright © 2016 Elsevier Inc. All rights reserved.

Computational Wear Simulation of Patellofemoral Articular Cartilage during In Vitro Testing

PubMed Central

Li, Lingmin; Patil, Shantanu; Steklov, Nick; Bae, Won; Temple-Wong, Michele; D'Lima, Darryl D.; Sah, Robert L.; Fregly, Benjamin J.

2011-01-01

Though changes in normal joint motions and loads (e.g., following anterior cruciate ligament injury) contribute to the development of knee osteoarthritis, the precise mechanism by which these changes induce osteoarthritis remains unknown. As a first step toward identifying this mechanism, this study evaluates computational wear simulations of a patellofemoral joint specimen wear tested on a knee simulator machine. A multi-body dynamic model of the specimen mounted in the simulator machine was constructed in commercial computer-aided engineering software. A custom elastic foundation contact model was used to calculate contact pressures and wear on the femoral and patellar articular surfaces using geometry created from laser scan and MR data. Two different wear simulation approaches were investigated – one that wore the surface geometries gradually over a sequence of 10 one-cycle dynamic simulations (termed the “progressive” approach), and one that wore the surface geometries abruptly using results from a single one-cycle dynamic simulation (termed the “non-progressive” approach). The progressive approach with laser scan geometry reproduced the experimentally measured wear depths and areas for both the femur and patella. The less costly non-progressive approach predicted deeper wear depths, especially on the patella, but had little influence on predicted wear areas. Use of MR data for creating the articular and subchondral bone geometry altered wear depth and area predictions by at most 13%. These results suggest that MR-derived geometry may be sufficient for simulating articular cartilage wear in vivo and that a progressive simulation approach may be needed for the patella and tibia since both remain in continuous contact with the femur. PMID:21453922

Computational wear simulation of patellofemoral articular cartilage during in vitro testing.

PubMed

Li, Lingmin; Patil, Shantanu; Steklov, Nick; Bae, Won; Temple-Wong, Michele; D'Lima, Darryl D; Sah, Robert L; Fregly, Benjamin J

2011-05-17

Though changes in normal joint motions and loads (e.g., following anterior cruciate ligament injury) contribute to the development of knee osteoarthritis, the precise mechanism by which these changes induce osteoarthritis remains unknown. As a first step toward identifying this mechanism, this study evaluates computational wear simulations of a patellofemoral joint specimen wear tested on a knee simulator machine. A multibody dynamic model of the specimen mounted in the simulator machine was constructed in commercial computer-aided engineering software. A custom elastic foundation contact model was used to calculate contact pressures and wear on the femoral and patellar articular surfaces using geometry created from laser scan and MR data. Two different wear simulation approaches were investigated--one that wore the surface geometries gradually over a sequence of 10 one-cycle dynamic simulations (termed the "progressive" approach), and one that wore the surface geometries abruptly using results from a single one-cycle dynamic simulation (termed the "non-progressive" approach). The progressive approach with laser scan geometry reproduced the experimentally measured wear depths and areas for both the femur and patella. The less costly non-progressive approach predicted deeper wear depths, especially on the patella, but had little influence on predicted wear areas. Use of MR data for creating the articular and subchondral bone geometry altered wear depth and area predictions by at most 13%. These results suggest that MR-derived geometry may be sufficient for simulating articular cartilage wear in vivo and that a progressive simulation approach may be needed for the patella and tibia since both remain in continuous contact with the femur. Copyright © 2011 Elsevier Ltd. All rights reserved.

Failure of total knee arthroplasty with or without patella resurfacing

PubMed Central

2011-01-01

Background and purpose Patella resurfacing during primary total knee arthroplasty (TKA) is disputed and new prosthesis designs have been introduced without documentation of their survival. We assessed the impact on prosthesis survival of patella resurfacing and of prosthesis brand, based on data from the Norwegian Arthroplasty Register. Patients and methods 5 prosthesis brands in common use with and without patella resurfacing from 1994 through 2009 were included n = 11,887. The median follow-up times were 9 years for patella-resurfaced implants and 7 years for implants without patella resurfacing. For comparison of prosthesis brands, also brands in common use with only one of the two treatment options were included in the study population (n = 25,590). Cox regression analyses were performed with different reasons for revision as endpoints with adjustment for potential confounders. Results We observed a reduced overall risk of revision for patella resurfaced (PR) TKAs, but the statistical significance was borderline (RR = 0.84, p = 0.05). At 15 years, 92% of PR and 91% of patella non resurfaced (NR) prostheses were still unrevised. However, PR implants had a lower risk of revision due to pain alone (RR = 0.1, p < 0.001), but a higher risk of revision due to loosening of the tibial component (RR = 1.4, p = 0.03) and due to a defective polyethylene insert (RR = 3.2, p < 0.001). At 10 years, the survival for the reference NR brand AGC Universal was 93%. The NR brands Genesis I, Duracon, and Tricon (RR = 1.4–1.7) performed statistically significantly worse than NR AGC Universal, while the NR prostheses e.motion, Profix, and AGC Anatomic (RR = 0.1–0.7), and the PR prostheses NexGen and AGC Universal (RR = 0.4–0.5) performed statistically significantly better. LCS, NexGen, LCS Complete (all NR), and Tricon, Genesis I, LCS, and Kinemax (all PR) showed no differences in this respect from the reference brand. A lower risk of revision (crude) was found for TKAs performed after 2000 as compared to those performed earlier (RR = 0.8, p = 0.001). Interpretation Although revision risk was similar for PR and NR TKAs, we found important differences in reasons for revision. Our results also indicate that survivorship of TKAs has improved. PMID:21619502

[Medial patellofemoral ligament reconstruction using quadriceps tendon].

PubMed

Lenschow, S; Herbort, M; Fink, C

2015-12-01

Stabilization of the patella by medial patellofemoral ligament (MPFL) reconstruction. Recurrent lateral patella instability with chronic weakening of the MPFL. Femoropatellar cartilage defects ICRS grade 3° or higher. Tuberositas Tibiae Trochlear Groove Index (TTTG) >20 mm. Lateral hypercompression of the patella without instability. A 3 cm transverse skin incision at the superomedial edge of the patella in 90° of flexion. Longitudinal incision of the prepatellar bursa and exposure of the quadriceps tendon. Preparation of a flat tendon strip with a length of 8 cm, a width of 10 mm, and a thickness of 3 mm, leaving the attachment at the patella intact. Flipping of the tendon strip and passing of the graft through a tunnel underneath the prepatellar tissue at the medial edge of the patella. Passing of the graft in layer two of the medial joint capsule just below the fascia (layer 1) and the vastus medialis. Fixation of the graft in a bone tunnel, drilled in the femoral insertion site of the native MPFL using a biodegradable interference screw. Patella centralizing brace for 4 weeks with range of motion (ROM) 0/0/90°, 20 kg of partial weight bearing for 3 weeks. Full weight-bearing according to pain starting from week 4 postoperatively. ROM up to 90° of flexion directly postoperatively. Free ROM starting from week 6 postoperatively. Stationary cycling 6 weeks postoperatively. Swimming and running after 10 months. Return to pivoting sports after 4-5 months. A total of 17 patients (7 men and 10 women; average age 21.5 years ±3.9 years, average BMI 22.6 ±3.9) were treated using this technique between March 2011 and November 2012. Only patients with at least one recurrent patella dislocation following conservative treatment were included. Patient satisfaction 12 months postoperatively was very high. Overall, 94.1 % would undergo the procedure again and 94.1 % were very satisfied with the cosmetic result. Significant improvement in Lysholm score 6, 12, and 24 months postoperatively (p < 0.05). Free ROM in 94.1 % of cases 12 months postoperatively. The Kujala score was reported to be 89 (±7.1) 12 months following surgery. No redislocation occurred during the 24 months following surgery.

Modeling and analysis of elastic fields in tibia and fibula

NASA Astrophysics Data System (ADS)

Ghosh, M.; Chowdhury, B. U.; Parvej, M. S.; Afsar, A. M.

2017-12-01

In this study, stress analysis of tibia and fibula subjected to body weight in static condition was carried out. The tibia and fibula were fabricated by casting process. A 3-D solid model of tibia and fibula was developed in SolidWorks by using the geometry of cross sections at different locations of the fabricated tibia and fibula. The 3-D model was analyzed by ANSYS to evaluate the stress, strain, and deformation for identifying the critical sections of tibia and fibula. It is found that, in terms of deformation, the critical zone is the contact zone between tibia-fibula and patella. However, in terms of stress, the critical zone is located on fibula between 25% and 40% height from the lower mating portion of the tibia and fibula.

Automatic Insall-Salvati ratio measurement on lateral knee x-ray images using model-guided landmark localization

NASA Astrophysics Data System (ADS)

Chen, Hsin-Chen; Lin, Chii-Jeng; Wu, Chia-Hsing; Wang, Chien-Kuo; Sun, Yung-Nien

2010-11-01

The Insall-Salvati ratio (ISR) is important for detecting two common clinical signs of knee disease: patella alta and patella baja. Furthermore, large inter-operator differences in ISR measurement make an objective measurement system necessary for better clinical evaluation. In this paper, we define three specific bony landmarks for determining the ISR and then propose an x-ray image analysis system to localize these landmarks and measure the ISR. Due to inherent artifacts in x-ray images, such as unevenly distributed intensities, which make landmark localization difficult, we hence propose a registration-assisted active-shape model (RAASM) to localize these landmarks. We first construct a statistical model from a set of training images based on x-ray image intensity and patella shape. Since a knee x-ray image contains specific anatomical structures, we then design an algorithm, based on edge tracing, for patella feature extraction in order to automatically align the model to the patella image. We can estimate the landmark locations as well as the ISR after registration-assisted model fitting. Our proposed method successfully overcomes drawbacks caused by x-ray image artifacts. Experimental results show great agreement between the ISRs measured by the proposed method and by orthopedic clinicians.

In defense of the classical height system

NASA Astrophysics Data System (ADS)

Foroughi, Ismael; Vaníček, Petr; Sheng, Michael; Kingdon, Robert William; Santos, Marcelo C.

2017-11-01

In many European countries, normal heights referred to the quasi-geoid as introduced by Molodenskij in the mid-20th century are preferred to the classical height system that consists of orthometric heights and the geoid as a reference surface for these heights. The rationale for this choice is supposed to be that in the classical height system, neither the geoid, nor the orthometric height can be ever known with centimetre level accuracy because one would need to know the topographical mass density to a level that can never be achieved. The aim of this paper is to question the validity of this rationale. The common way of assessing the congruency of a local geoid model and the orthometric heights is to compare the geoid heights with the difference between orthometric heights provided by leveling and geodetic heights provided by GNSS. On the other hand, testing the congruency of a quasi-geoidal model with normal height a similar procedure is used, except that instead of orthometric heights, normal heights are employed. For the area of Auvergne, France, which is now a more or less standard choice for precise geoid or quasi-geoid testing, only the normal heights are supplied by the Institute Geographic National, the provider of the data. This is clearly the consequence of the European preference for the Molodenskij system. The quality of the height system is to be judged by the congruency of the difference of the geoid/quasi-geoid heights subtracted from the geodetic heights and orthometric/normal heights. To assess the congruency of the classical height system, the Helmert approximation of orthometric heights is typically used as the transformation between normal and Helmert's heights is easily done. However, the evaluation of the differences between Helmert's and the rigorous orthometric heights is somewhat more involved as will be seen from the review in this paper. For the area of interest, the differences between normal and Helmert's heights at the control leveling points range between - 9.5 and 0 cm, differences between Helmert's and the rigorous orthometric heights vary between - 3.6 and 1.1 cm. The local gravimetric geoid model of Auvergne, computed by the Stokes-Helmert technique, is used here to illustrate the accuracy of the classical height system. Results show a very reasonable standard deviation (STD) of 3.2 cm of the differences between geoid values, derived from control leveling points, and gravimetric geoid heights when Helmert's heights are employed and even a smaller STD of 2.9 cm when rigorous orthometric heights are used. A corresponding comparison of a quasi-geoid model, computed by Least-Squares Modification of Stokes method, with normal heights show an STD of 3.4 cm.

The Impact of Adolescent Obesity on Adult Height.

PubMed

Brener, Avivit; Bello, Rachel; Lebenthal, Yael; Yackobovitch-Gavan, Michal; Phillip, Moshe; Shalitin, Shlomit

2017-01-01

Childhood obesity is a major health concern. Excess adiposity during childhood affects growth and puberty. Our aim was to assess whether genetic adult height is compromised in adolescents with obesity. In a retrospective study of 190 obese patients followed at our Pediatric Endocrinology Institute, adult height and delta height (the difference between adult height and mid-parental height) were compared to those of 150 healthy age-matched normal-weight controls. Review of medical files yielded the relevant clinical and anthropometric data of patients, controls, and parents. Of the 190 obese adolescents, 150 were morbidly obese. The median adult height of morbidly obese males was 174.3 cm, of obese males 174 cm, and of normal-weight males 176 cm (p = 0.025). Delta height of morbidly obese males was -0.5 cm, of obese males -0.8 cm, and of normal-weight males, 3 cm (p < 0.0001). The median adult height of morbidly obese females was 161.3 cm, of obese females 162.8 cm, and of normal-weight females 162 cm (p = 0.37). Delta height of morbidly obese females was -1.85 cm, of obese females -0.95 cm, and of normal-weight females 0.7 cm (p = 0.019). Impairment of potential genetic height was not associated with obesity-related comorbidities. Adolescents with obesity showed impairment of potential genetic adult height as compared to that of normal-weight subjects. © 2017 S. Karger AG, Basel.

Distal tibial tuberosity translation using TTA implants for the treatment of patella alta in large breed dogs. Surgical technique and clinical outcome.

PubMed

Pugliese, L C; Pike, F S; Aiken, S W

2015-01-01

Medial patellar luxation frequently occurs in dogs resulting in lameness with increasing incidence in large breed dogs. Patella alta has been defined as a patellar ligament length to patellar length ratio that is greater than two and may predispose to patellar luxation. To describe the surgical technique for stabilization of the distal translation of the tibial tuberosity using tibial tuberosity advancement plates and the clinical outcomes with follow-up for clinical cases of dogs. Dogs that were presented with the complaint of patellar luxation and that were concurrently diagnosed with patella alta and were greater than 20 kg in body weight underwent surgery using a tibial tuberosity advancement plate to stabilize the osteotomy. Radiographic assessment of A:PL distance (the ratio of the proximal aspect of the patella to the femoral condyle [A] to the patellar length [PL]), L:P ratio (ratio of the length of the patellar ligament to the diagonal length of the patella), and owner assessment were obtained. Eleven stifles in nine dogs underwent surgical correction with a mean preoperative L:P ratio of 2.47. There were no complications and the lameness resolved clinically. The mean A:PL ratios preoperatively (2.6 ± 0.22) and postoperatively (2.1 ± 0.25) were significantly different (p = 0.0003). All owners were satisfied with the outcome and all dogs had a resolution of lameness with no recurrence of patellar luxation. Stabilization of distal translation of the tibial tuberosity using tibial tuberosity advancement implants to correct patella alta in large breed dogs was feasible and resulted in good clinical outcome.

Optimized cartilage visualization using 7-T sodium ((23)Na) imaging after patella dislocation.

PubMed

Widhalm, Harald K; Apprich, Sebastian; Welsch, Goetz H; Zbyn, Stefan; Sadoghi, Patrick; Vekszler, György; Hamböck, Martina; Weber, Michael; Hajdu, Stefan; Trattnig, Siegfried

2016-05-01

Retropatellar cartilage lesions often occur in the course of recurrent patella dislocation. Aim of this study was to develop a more detailed method for examining cartilage tissue, in order to reduce patient discomfort and time of care. For detailed diagnosing, a 7-T MRI of the knee joint and patella was performed in nine patients, with mean age of 26.4 years, after patella dislocation to measure the cartilage content in three different regions of interest of the patella. Axial sodium ((23)Na) images were derived from an optimized 3D GRE sequence on a 7-T MR scanner. Morphological cartilage grading was performed, and sodium signal-to-noise ratio (SNR) values were calculated. Mean global sodium values and SNR were compared between patients and volunteers. Two out of nine patients showed a maximum cartilage defect of International Cartilage Repair Society (ICRS) grade 3, three of grade 2, three of  grade 1, and one patient showed no cartilage defect. The mean SNR in sodium images for cartilage was 13.4 ± 2.5 in patients and 14.6 ± 3.7 in volunteers (n.s.). A significant negative correlation between age and global sodium SNR for cartilage was found in the medial facet (R = -0.512; R (2) = 0.26; p = 0.030). Mixed-model ANOVA yielded a marked decrease of the sodium SNR, with increasing grade of cartilage lesions (p < 0.001). Utilization of the (23)Na MR imaging will make earlier detection of alterations to the patella cartilage after dislocation possible and will help prevent subsequent disease due to start adequate therapy earlier in the rehabilitation process. II.

A Case Report of Sleeve Fracture of the Patella in a Shield.

PubMed

Tsubosaka, Masanori; Makino, Takeshi; Kishimoto, Shin-Ichiro; Yamaura, Kohei

2016-01-01

Sleeve fractures of the patella are rare fractures that only occur in children. The diagnosis is difficult both clinically and radiologically since the distal bony fragment may be too small to be detectable by radiography. A high-riding patella and hemarthrosis are important signs of sleeve fractures. A 12-year-old boy was admitted to the emergency room after having felt a severe pain in his left knee on kicking the ground while skateboarding earlier that day. Knee swelling, tense hemarthrosis, and periarticular tenderness were noted. On physical examination, an extension lag of 15 was observed. The active range of motion of the injured knee was 45-90° of flexion. Radiography showed an avulsion fracture of the lower pole of the patella and a high-riding patella. At the next day after the injury, we performed open reduction and internal fixation surgery. Open reduction with transosseous tunneling and cerclage wiring was performed because the distal bony fragment was too small for tension band wiring to be used. At 9 months after surgery, there was no extension lag, and the active range of motion of the injured knee was 0-140° of flexion. Callus formation over the fracture site and bone union was confirmed, and the cerclage wire was removed. To date, he had no further symptoms and has been able to carry out all types of physical activities, including skateboarding. Although sleeve fractures in children are uncommon, it should be considered a possibility in children with a chief complaint of pain around the knee. Open reduction and internal fixation was effective in the treatment of sleeve fracture of the patella.

Biologic resurfacing of the patella: current status.

PubMed

Scapinelli, Raphaele; Aglietti, Paolo; Baldovin, Marino; Giron, Francesco; Teitge, Robert

2002-07-01

The techniques of biologic resurfacing of the patella, like other joint surfaces, are still evolving. Currently none of them is free from criticism. In this regard it is our hope that progress in the basic science will offer in the near future new and more optimistic therapeutic possibilities (i.e., the restoration of a reparative cartilage that is structurally and functionally comparable to the native one). The greater expectancies come perhaps from the present experimental investigations about the combined use of tissue-engineered implants embedded with staminal cells and growth factors. Many problems remain to be solved, however, before reliable applicability in humans. From a general point of view, stem cells obtained from various sources (e.g., adult bone marrow, umbilical cord) offer the same finalities as the embryonic stem cells, without the ethical obstacles related to the latter. Therefore, it may be that restoration of part or all of the articular surface of a joint will be possible by way of these mesenchymal progenitors that have the ability to differentiate into the chondrogenic and osteogenic lines, which is required for the restoration of the various layers of a normal articular cartilage and subchondral bone.

Opto-numerical procedures supporting dynamic lower limbs monitoring and their medical diagnosis

NASA Astrophysics Data System (ADS)

Witkowski, Marcin; Kujawińska, Malgorzata; Rapp, Walter; Sitnik, Robert

2006-01-01

New optical full-field shape measurement systems allow transient shape capture at rates between 15 and 30 Hz. These frequency rates are enough to monitor controlled movements used e.g. for medical examination purposes. In this paper we present a set of algorithms which may be applied for processing of data gathered by fringe projection method implemented for lower limbs shape measurement. The purpose of presented algorithms is to locate anatomical structures based on the limb shape and its deformation in time. The algorithms are based on local surface curvature calculation and analysis of curvature maps changes during the measurement sequence. One of anatomical structure of high medical interest that is possible to scan and analyze, is patella. Tracking of patella position and orientation under dynamic conditions may lead to detect pathological patella movements and help in knee joint disease diagnosis. Therefore the usefulness of the algorithms developed was proven at examples of patella localization and monitoring.

Comparison of axial T1 spin-echo and T1 fat-saturation magnetic resonance imaging techniques in the diagnosis of chondromalacia patellae.

PubMed

Vanarthos, W J; Pope, T L; Monu, J U

1994-12-01

To test the diagnostic value of T1 spin-echo and T1 fat-saturated magnetic resonance images (MRIs), we reviewed axial T1-weighted images with and without fat saturation in 20 patients with clinically suspected chondromalacia of the patella. All scans were obtained on 1.5-MR units. The scans were randomly ordered and reviewed independently at different times by two radiologists without knowledge of the arthroscopy results. The sensitivity of the individual techniques for detecting grade 3 or 4 chondromalacia patellae was 92% for fat-saturated axial T1-weighted images alone, and 67% for axial T1-weighted images without fat saturation. The sensitivity of the combined techniques was 100% for grades 3 and 4 and 90% for all grades (0 to 4). Chondromalacia patellae is diagnosed more accurately by using T1 fat saturation than by using T1 spin-echo images. With a combination of the two techniques, accuracy is 90% to 100%.

Factors affecting the outcomes of modified tension band wiring techniques in transverse patellar fractures.

PubMed

Hsu, Kai-Lan; Chang, Wei-Lun; Yang, Chyun-Yu; Yeh, Ming-Long; Chang, Chih-Wei

2017-12-01

Modified tension band wiring has been widely used to treat transverse patellar fractures. However, few studies have evaluated the clinical outcomes using different methods of Kirschner wire bending, location of the tension band, and depths of Kirschner wires. Thus, we tried to clarify these factors according to our clinical outcomes. This retrospective cohort study recruited consecutive patients underwent surgical fixation for patellar fractures using modified tension band technique between January 2010 and December 2015. Different factors in this procedure, including the bending manner of the Kirschner wires, their depth, and location of the tension band with respect to the superior and inferior border of the patella were recorded and analysed. The primary outcome was early loss of fixation. The secondary outcomes were minor loss of reduction, implant breakage, deep infection, and the need for implant removal. This study included 170 patients with patellar fractures. Regarding the bending method, similar results were obtained with bilaterally or proximally bent Kirschner wires. Regarding length, the tension band was placed closely (within 25% of the patella length) in 124 patients and distantly in 46 patients. The rates of loss of reduction and implant breakage were significantly higher in the distantly placed tension bands. Regarding depth, 37 patellar fractures were fixed with the Kirschner wires at the superficial one third of the patellae while the K- wires at the middle layer of patella were used in the remaining 133 patellar fractures. A significantly higher rate of minor loss of reduction was obtained using the superficial Kirschner wires. The modified tension band technique for transverse patella fractures provides favourable clinical outcomes, with low failure (5%) and infection (2%) rates. Implant irritation is the major complication, and almost half of cases require implant removal. The location of the tension band with respect to the superior and inferior border of the patella plays an important role in clinical outcomes. Placing the wire close to the patella may prevent major loss of reduction and implant breakage. Superficially placed Kirschner wires also affect clinical outcomes by increasing the rate of minor loss of reduction. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of strength training on human patella tendon mechanical properties of older individuals

PubMed Central

Reeves, N D; Maganaris, C N; Narici, M V

2003-01-01

This study investigated the effect of strength training on the mechanical properties of the human patella tendon of older individuals. Subjects were assigned to training (n = 9; age 74.3 ± 3.5 years, body mass 69.7 ± 14.8 kg and height 163.4 ± 9.1 cm, mean ±s.d.) and control (n = 9; age 67.1 ± 2 years, body mass 73.5 ± 14.9 kg and height 168.3 ± 11.5 cm) groups. Strength training (two series of 10 repetitions at 80 % of five-repetition maximum) was performed three times per week for 14 weeks using leg extension and leg press exercises. Measurements of tendon elongation during a ramp isometric knee extension were performed before and after training and control periods in vivo using ultrasonography. Training caused a decreased tendon elongation and strain at all levels of force and stress (P < 0.01). Baseline tendon elongation and strain at maximal tendon load were 4.7 ± 1.1 mm and 9.9 ± 2.2 %, respectively (maximum force: 3346 ± 1168 N; maximum stress: 40 ± 11 MPa). After training, these values decreased to 2.9 ± 1.2 mm and 5.9 ± 2.4 % (P < 0.01), respectively (maximum force: 3555 ± 1257 N; maximum stress: 42 ± 11 MPa). Tendon stiffness increased by 65 % (2187 ± 713 to 3609 ± 1220 N mm−1; P < 0.05) and Young's modulus increased by 69 % (1.3 ± 0.3 to 2.2 ± 0.8 GPa; P < 0.01). As a result of these changes, the rate of torque development increased by 27 % (482.8 ± 302.5 to 612.6 ± 401 N m s−1; P < 0.01) following training. No significant changes occurred in any measured variables in the control group (P > 0.05). This study shows for the first time that strength training in old age increases the stiffness and Young's modulus of human tendons. This may reduce the risk of tendon injury in old age and has implications for contractile force production and the rapid execution of motor tasks. PMID:12626673

The role of autologous chondrocyte implantation in the treatment of symptomatic chondromalacia patellae.

PubMed

Macmull, Simon; Jaiswal, Parag K; Bentley, George; Skinner, John A; Carrington, Richard W J; Briggs, Tim W R

2012-07-01

Chondromalacia patella is a distinct clinical entity of abnormal softening of the articular cartilage of the patella, which results in chronic retropatellar pain. Its aetiology is still unclear but the process is thought to be a due to trauma to superficial chondrocytes resulting in a proteolytic enzymic breakdown of the matrix. Our aim was to assess the effectiveness of autologous chondrocyte implantation on patients with a proven symptomatic retropatellar lesion who had at least one failed conventional marrow-stimulating therapy. We performed chondrocyte implantation on 48 patients: 25 received autologous chondrocyte implantation with a type I/III membrane (ACI-C) method (Geistlich Biomaterials, Wolhusen, Switzerland), and 23 received the Matrix-assisted Chondrocyte Implantation (MACI) technique (Genzyme, Kastrup, Denmark). Over a mean follow-up period of 40.3 months, there was a statistically significant improvement in subjective pain scoring using the visual analogue scale (VAS) and objective functional scores using the Modified Cincinnati Rating System (MCS) in both groups. Chondromalacia patellae lesions responded well to chondrocyte implantation. Better results occurred with MACI than with ACI-C. Excellent and good results were achieved in 40% of ACI-C patients and 57% of MACI patients, but success of chondrocyte implantation was greater with medial/odd-facet lesions. Given that the MACI procedure is technically easier and less time consuming, we consider it to be useful for treating patients with symptomatic chondral defects secondary to chondromalacia patellae.

Correlation of 3D Shift and 3D Tilt of the Patella in Patients With Recurrent Dislocation of the Patella and Healthy Volunteers: An In Vivo Analysis Based on 3-Dimensional Computer Models.

PubMed

Yamada, Yuzo; Toritsuka, Yukiyoshi; Nakamura, Norimasa; Horibe, Shuji; Sugamoto, Kazuomi; Yoshikawa, Hideki; Shino, Konsei

2017-11-01

The concepts of lateral deviation and lateral inclination of the patella, characterized as shift and tilt, have been applied in combination to evaluate patellar malalignment in patients with patellar dislocation. It is not reasonable, however, to describe the 3-dimensional (3D) positional relation between the patella and the femur according to measurements made on 2-dimensional (2D) images. The current study sought to clarify the relation between lateral deviation and inclination of the patella in patients with recurrent dislocation of the patella (RDP) by redefining them via 3D computer models as 3D shift and 3D tilt. Descriptive laboratory study. Altogether, 60 knees from 56 patients with RDP and 15 knees from 10 healthy volunteers were evaluated. 3D shift and tilt of the patella were analyzed with 3D computer models created by magnetic resonance imaging scans obtained at 10° intervals of knee flexion (0°-50°). 3D shift was defined as the spatial distance between the patellar reference point and the midsagittal plane of the femur; it is expressed as a percentage of the interepicondylar width. 3D tilt was defined as the spatial angle between the patellar reference plane and the transepicondylar axis. Correlations between the 2 parameters were assessed with the Pearson correlation coefficient. The patients' mean Pearson correlation coefficient was 0.895 ± 0.186 (range, -0.073 to 0.997; median, 0.965). In all, 56 knees (93%) had coefficients >0.7 (strong correlation); 1 knee (2%), >0.4 (moderate correlation); 2 knees (3%), >0.2 (weak correlation); and 1 knee (2%), <0.2 (no correlation). The mean correlation coefficient of the healthy volunteers was 0.645 ± 0.448 (range, -0.445 to 0.982; median, 0.834). A statistically significant difference was found in the distribution of the correlation coefficients between the patients and the healthy volunteers ( P = .0034). When distribution of the correlation coefficients obtained by the 3D analyses was compared with that by the 2D (conventional) analyses, based on the bisect offset index and patellar tilt angle, the 3D analyses showed statistically higher correlations between the lateral deviation and inclination of the patella ( P < .01). 3D shift and 3D tilt of the patella were moderately or strongly correlated in 95% of patients with RDP at 0° to 50° of knee flexion. It is not always necessary to use both parameters when evaluating patellar alignment, at least for knees with RDP at 0° to 50° of flexion. Such a description may enable surgeons to describe patellar alignment more simply, leading to a better, easier understanding of the characteristics of each patient with RDP.

Women in the Army Policy Review

DTIC Science & Technology

1982-11-12

chondromalacia of the perfornmance-limiting conditions thait *eiulted from an 8-1%eek patella (21). hip or neck of femur stress fracture (20). sprains...by the Chondromalacia of patella 21 10 Hip or neck or femur stress fracture 20 9 apparent lack of heel stability inherent in ;he Army boot used Ankle

[Osteoblastoma of the patella (author's transl)].

PubMed

Sicard, A; Touzard, R C; Squalli, S

1979-01-01

Osteoblastoma is a rare bony tumour. Its localisation at the level of the patella seems exceptional. Our case is the third published case. Wide curetage was a failure, and did not permit histological diagnosis. A cure was obtained by patellectomy, after which the diagnosis of the lesion was made without any doubt.

Rare sleeve fracture of the superior patella pole in an adult due to forceful passive physiotherapy following cast immobilization.

PubMed

Ro, Kyung-Han; Park, Jong-Hoon; Kim, Myo-Jong; Lee, Dae-Hee

2014-03-01

Sleeve fractures are generally restricted to children or adolescents, and usually occur at the lower patella pole. Here we report on a superior pole sleeve fracture in an adult that occurred following forceful passive physiotherapy after cast immobilization. To our knowledge, this is the first report of a superior pole sleeve fracture in an otherwise healthy adult. The case highlighted that a diagnosis of a superior patella pole sleeve fracture in an adult can easily be missed because it is a rare injury, and hence is unlikely to be suspected by physicians. Copyright © 2013 Elsevier B.V. All rights reserved.

Articular cartilage changes in chondromalacia patellae.

PubMed

Bentley, G

1985-11-01

Full thickness samples of articular cartilage were removed from areas of chondromalacia on the medial and "odd" facets of the patellae of 21 adults and examined by histology, autoradiography and electron microscopy. Surface fibrillation, loss of superficial matrix staining and reduced 35SO4 labelling was seen, with little change in the deep zone. Ten cases showed "fibrous metaplasia" of the superficial cartilage with definite evidence of cell division and apparent smoothing of the surface. Scattered chondrocyte replication appeared to occur in the surrounding intact cartilage. The findings suggest that early lesions in chondromalacia patellae may heal either by cartilage or fibrous metaplasia and that this may account for the resolution of clinical symptoms.

Pulsatile and steady-state hemodynamics of the human patella bone by diffuse optical spectroscopy.

PubMed

Farzam, Parisa; Zirak, Peyman; Binzoni, Tiziano; Durduran, Turgut

2013-08-01

The cardiac cycle related pulsatile behavior of the absorption and scattering coefficients of diffuse light and the corresponding alterations in hemoglobin concentrations in the human patella was studied. The pulsations in scattering is considerably smaller than absorption. The difference in amplitude of absorption coefficient pulsations for different wavelengths was translated to pulsations in oxygenated and deoxygenated hemoglobin, which leads to strong pulsations in the total hemoglobin concentration and oxygen saturation. The physiological origin of the observed signals was confirmed by applying a thigh-cuff. Moreover, we have investigated the optical and physiological properties of the patella bone and their changes in response to arterial cuff occlusion.

[Surgical treatment of inferior pole comminuted fractures of patella with new type tension band].

PubMed

Sun, B; Zhang, Z S; Zhou, F; Tian, Y; Ji, H Q; Guo, Y; Lv, Y; Yang, Z W

2015-04-18

To study the effectiveness of inferior pole fracture of patella treating by the new tension band. From Dec. 2011 to Dec. 2013, 21 patients with inferior pole fracture of patella were treated with the new tension band which consisted of cannulated screw, titanium cable and shims. There were 21 patients[10 males, 11 females, the average age was 54 years(21 to 79)],of whom,all were "fell on knees". The average operation time was 89 min (57-197 min),the follow-up visits were done from 7-31 months (average 18 months), the bone healing time was from 8-12 weeks (average 10.5 weeks). The post operation assessment was done by Bostman score, from 20-30 (average 27),10 excellent,and 11 good. No complication occurred. The new tension band is the effective treatment for inferior pole fracture of patella. The internal fixation is reliable, it is simple to operate, and patients can take exercises as early as possible. Therefore, the new tension band has a better clinical value.

Noninvasive acceleration measurements to characterize knee arthritis and chondromalacia.

PubMed

Reddy, N P; Rothschild, B M; Mandal, M; Gupta, V; Suryanarayanan, S

1995-01-01

Devising techniques and instrumentation for early detection of knee arthritis and chondromalacia presents a challenge in the domain of biomedical engineering. The purpose of the present investigation was to characterize normal knees and knees affected by osteoarthritis, rheumatoid arthritis, and chondromalacia using a set of noninvasive acceleration measurements. Ultraminiature accelerometers were placed on the skin over the patella in four groups of subjects, and acceleration measurements were obtained during leg rotation. Acceleration measurements were significantly different in the four groups of subjects in the time and frequency domains. Power spectral analysis revealed that the average power was significantly different for these groups over a 100-500 Hz range. Noninvasive acceleration measurements can characterize the normal, arthritis, and chondromalacia knees. However, a study on a larger group of subjects is indicated.

Non-resurfacing techniques in the management of the patella at total knee arthroplasty: A systematic review and meta-analysis.

PubMed

Findlay, I; Wong, F; Smith, C; Back, D; Davies, A; Ajuied, A

2016-03-01

Recent meta-analyses support not resurfacing the patella at the time of TKA. Several different modes of intervention are reported for non-resurfacing management of the patella at TKA. We have conducted a systematic review and meta-analysis of non-resurfacing interventions in TKA. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) study methodology and reporting system was adopted, utilising the PRISMA checklist and statement. Classes of patella interventions were defined as: 0. No intervention. 1. Osteophyte excision only. 2. Osteophyte excision, denervation, with soft tissue debridement. 3. Osteophyte excision, denervation, soft tissue debridement, and drilling or micro-fracture of eburnated bone. 4. Patellar resurfacing. A meta-analysis was conducted upon the pre- and post-operative KSS for each technique. Four hundred and twenty-three studies were identified, 12 studies met the inclusion criteria for the systematic review and eight for the meta-analysis. Two studies compared different non-resurfacing patellar techniques, the other studies used the non-resurfacing cohort as controls for their prospective RCTs comparing patellar resurfacing with non-resurfacing. The meta-analysis revealed no significant difference between the techniques. We conclude that there is no significant difference in KSS for differing non-resurfacing patellar techniques, but further trials using patellofemoral specific scores may better demonstrate superior efficacy of specific classes of patella intervention, by virtue of greater sensitivity for patellofemoral pain and dysfunction. I. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Runners with Patellofemoral Pain Exhibit Greater Peak Patella Cartilage Stress Compared to Pain-Free Runners.

PubMed

Liao, Tzu-Chieh; Keyak, Joyce H; Powers, Christopher M

2018-02-27

The purpose of this study is to determine whether recreational runners with patellofemoral pain (PFP) exhibit greater peak patella cartilage stress compared to pain-free runners. A secondary purpose was to determine the kinematic and/or kinetic predictors of peak patella cartilage stress during running. Twenty-two female recreational runners participated (12 with PFP and 10 pain-free controls). Patella cartilage stress profiles were quantified using subject-specific finite element models simulating the maximum knee flexion angle during stance phase of running. Input parameters to the finite element model included subject-specific patellofemoral joint geometry, quadriceps muscle forces, and lower extremity kinematics in the frontal and transverse planes. Tibiofemoral joint kinematics and kinetics were quantified to determine the best predictor of stress using stepwise regression analysis. Compared to the pain-free runners, those with PFP exhibited greater peak hydrostatic pressure (PFP vs. control, 21.2 ± 5.6 MPa vs. 16.5 ± 4.6 MPa) and maximum shear stress (11.3 ± 4.6 MPa vs. 8.7 ± 2.3 MPa). Knee external rotation was the best predictor of peak hydrostatic pressure and peak maximum shear stress (38% and 25% of variances, respectively) followed by the knee extensor moment (21% and 25% of variances, respectively). Runners with PFP exhibit greater peak patella cartilage stress during running compared to pain-free individuals. The combination of knee external rotation and a high knee extensor moment best predicted elevated peak stress during running.

Vastus medialis cross-sectional area is positively associated with patella cartilage and bone volumes in a pain-free community-based population

PubMed Central

Berry, Patricia A; Teichtahl, Andrew J; Galevska-Dimitrovska, Ana; Hanna, Fahad S; Wluka, Anita E; Wang, Yuanyuan; Urquhart, Donna M; English, Dallas R; Giles, Graham G; Cicuttini, Flavia M

2008-01-01

Introduction Although vastus medialis and lateralis are important determinants of patellofemoral joint function, their relationship with patellofemoral joint structure is unknown. The aim of this study was to examine potential determinants of vastus medialis and lateralis cross-sectional areas and the relationship between the cross-sectional area and patella cartilage and bone volumes. Methods Two hundred ninety-seven healthy adult subjects had magnetic resonance imaging of their dominant knee. Vastus medialis and lateralis cross-sectional areas were measured 37.5 mm superior to the quadriceps tendon insertion at the proximal pole of the patella. Patella cartilage and bone volumes were measured from these images. Demographic data and participation in vigorous physical activity were assessed by questionnaire. Results The determinants of increased vastus medialis and lateralis cross-sectional areas were older age (P ≤ 0.002), male gender (P < 0.001), and greater body mass index (P ≤ 0.07). Participation in vigorous physical activity was positively associated with vastus medialis cross-sectional area (regression coefficient [beta] 90.0; 95% confidence interval [CI] 38.2, 141.7) (P < 0.001) but not with vastus lateralis cross-sectional area (beta 10.1; 95% CI -18.1, 38.3) (P = 0.48). The cross-sectional area of vastus medialis only was positively associated with patella cartilage volume (beta 0.6; 95% CI 0.23, 0.94) (P = 0.001) and bone volume (beta 3.0; 95% CI 1.40, 4.68) (P < 0.001) after adjustment for potential confounders. Conclusions Our results in a pain-free community-based population suggest that increased cross-sectional area of vastus medialis, which is associated with vigorous physical activity, and increased patella cartilage and bone volumes may benefit patellofemoral joint health and reduce the long-term risk of patellofemoral pathology. PMID:19077298

Clinical outcome after reconstruction of the medial patellofemoral ligament in paediatric patients with recurrent patella instability.

PubMed

Lind, Martin; Enderlein, Ditte; Nielsen, Torsten; Christiansen, Svend Erik; Faunø, Peter

2016-03-01

Medial patellofemoral ligament (MPFL) reconstruction has recently been broadly accepted as primary surgical treatment in adults. Reconstruction techniques with osseous fixation in femur cannot be used for patients with open growth plates. Operative treatment of patella instability in children therefore is a challenge and requires alternative MPFL reconstruction techniques. Limited knowledge exists concerning outcome after MPFL reconstruction in children and adolescents. This study present clinical outcome in a consecutive single clinic series of children treated with paediatric MPFL reconstruction using a soft tissue femoral fixation technique. Twenty-four MPFL reconstructions in 20 operated children aged 8-16 were included in the study. Indication for surgery was two or more patella dislocations. MPFL reconstruction was performed by looping the released gracilis tendon around the adductor magnus tendon insertion and through drill holes in the proximal medial patella edge. Clinical outcome was evaluated by Kujala score and NRS pain score preoperatively, at 1-year follow-up and final follow-up at 39 months. Outcome was compared with a cohort of 179 adult patients with recurrent patella instability operated with an adult MPFL reconstruction technique. Kujala score improved from 61 (13) to 81 (16). NRS pain score improved from 3.0 (3.1) to 1.5 (1.3) in activity. Four patients (20%) experienced redislocation within the first postoperative year compared with 5% in an adult patient population. Five patients (25%) experienced subluxations. One patient with a redislocation was re-operated with adult MPFL reconstruction technique. Cartilage injury was seen in six patients. There are clinical relevant improvements in knee function and pain after MPFL reconstruction in paediatric patients. Patella stability after MPFL reconstruction using femoral soft tissue graft fixation in paediatric patients was inferior to MPFL reconstruction using bony femoral fixation in adult patients. Case-Control study, Level III.

The Use of Mesh Plates for Difficult Fractures of the Patella.

PubMed

Volgas, David; Dreger, Tina K

2017-03-01

Patella fractures present some of the more complicated fracture patterns in orthopaedic trauma care. This is partially due to the small size of the fragments but also the articular nature of each fragment. Fixation methods such as cerclage wiring, excision of smaller fragments, and screw fixation of larger fragments all have their own challenges. Our study examined our Level I trauma center's experience with variable angle locked 2.7 mm titanium plates for treatment of comminuted patella fractures or treatment of patellar nonunion. After Institutional Review Board approval, we used billing records to identify 105 patients who had undergone operative management of a displaced patella fracture between January 2011 and December 2015. We reviewed the radiographs of these patients to identify which patients underwent treatment with a mesh plate. We found 16 patients (6 males and 10 females) who had undergone fixation with a mesh plate; mean age was 47 years. Nine patients underwent primary open reduction internal fixation (ORIF) and seven underwent mesh plate fixation for failed ORIF of a patella fracture. The mean visual analog pain score was 2.75 (range, 0-9). The mean range of motion was 1 degree of extension (range, 0-10 degrees) to 110 degrees of flexion (range, 45-135 degrees). All fractures healed. Five patients required hardware removal for pain. This review illustrates the effectiveness of the locking mesh plate in two challenging clinical scenarios: that of patellar nonunion and comminuted fractures that preclude standard fixation methods. Although multiple options exist for patellar fracture fixation, the titanium mesh locking plate can be an effective option for retaining the patella in the setting of comminution. Further comparative studies should be undertaken to determine which method of treatment may be superior in the treatment of these fractures. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

In vivo validation of patellofemoral kinematics during overground gait and stair ascent.

PubMed

Pitcairn, Samuel; Lesniak, Bryson; Anderst, William

2018-06-18

The patellofemoral (PF) joint is a common site for non-specific anterior knee pain. The pathophysiology of patellofemoral pain may be related to abnormal motion of the patella relative to the femur, leading to increased stress at the patellofemoral joint. Patellofemoral motion cannot be accurately measured using conventional motion capture. The aim of this study was to determine the accuracy of a biplane radiography system for measuring in vivo PF motion during walking and stair ascent. Four subjects had three 1.0 mm diameter tantalum beads implanted into the patella. Participants performed three trials each of over ground walking and stair ascent while biplane radiographs were collected at 100 Hz. Patella motion was tracked using radiostereophotogrammetric analysis (RSA) as a "gold standard", and compared to a volumetric CT model-based tracking algorithm that matched digitally reconstructed radiographs to the original biplane radiographs. The average RMS difference between the RSA and model-based tracking was 0.41 mm and 1.97° when there was no obstruction from the contralateral leg. These differences increased by 34% and 40%, respectively, when the patella was at least partially obstructed by the contralateral leg. The average RMS difference in patellofemoral joint space between tracking methods was 0.9 mm or less. Previous validations of biplane radiographic systems have estimated tracking accuracy by moving cadaveric knees through simulated motions. These validations were unable to replicate in vivo kinematics, including patella motion due to muscle activation, and failed to assess the imaging and tracking challenges related to contralateral limb obstruction. By replicating the muscle contraction, movement velocity, joint range of motion, and obstruction of the patella by the contralateral limb, the present study provides a realistic estimate of patellofemoral tracking accuracy for future in vivo studies. Copyright © 2018 Elsevier B.V. All rights reserved.

The Anatomic Midpoint of the Attachment of the Medial Patellofemoral Complex.

PubMed

Tanaka, Miho J; Voss, Andreas; Fulkerson, John P

2016-07-20

The medial patellofemoral ligament varies in attachment of its fibers to the patella and vastus intermedius tendon. Our aim was to identify and describe its anatomic midpoint. To account for the variability of the attachment site, we refer to it as the medial patellofemoral complex. Using AutoCAD software, we identified the midpoint of the medial patellofemoral complex attachment on photographs of 31 cadaveric knee dissections. The midpoint was referenced relative to the superior articular surface of the patella (P1) and was described in terms of the percentage of the patellar articular length distal to this point. A second point, at the junction of the medial border of the vastus intermedius tendon with the superior articular border of the patella, was identified (P2). The distances of the midpoint to P1 and P2 were calculated and were compared using paired t tests. Twenty-five images had appropriate quality and landmarks for digital analysis. The midpoint of the medial patellofemoral complex was located a mean (and standard deviation) of 2.3% ± 15.8% of the patellar articular length distal to the superior pole and was at or proximal to P1 in 12 knees. In all knees, the midpoint was at or proximal to P2. After exclusion of 2 knees with vastus intermedius tendon attachments only, the medial patellofemoral complex midpoint was closer to P2 (5.3% ± 8.6% of the patellar articular length) than to P1 (9.3% ± 8.5% of the patellar articular length) (p = 0.06). The midpoint of the medial patellofemoral complex was 2.3% of the articular length distal to the superior pole of the patella. Additionally, we describe an anatomic landmark at the junction of the medial border of the vastus intermedius tendon and the articular border of the patella that approximates the midpoint of this complex. Our study shows that the anatomic midpoint of the attachment of the medial patellofemoral complex is proximal to the junction of the medial vastus intermedius tendon and the articular border of the patella, suggesting that graft placement may be more anatomic on the vastus intermedius tendon rather than on the patella. Copyright © 2016 by The Journal of Bone and Joint Surgery, Incorporated.

Effect of aspirin treatment on chondromalacia patellae.

PubMed Central

Bentley, G; Leslie, I J; Fischer, D

1981-01-01

Twenty-nine patients (21 females and 8 males) with chondromalacia patellae diagnosed by arthroscopy were randomly allocated to receive aspirin or placebo for 3 months. Clinical and arthroscopic examination after 3 months showed no significant change in symptoms, signs, or macroscopic appearances in either group. Surgical treatment was performed in 14 patients for deteriorating symptoms. Images PMID:7008711

The association of patellofemoral joint morphology with chondromalacia patella: a quantitative MRI analysis.

PubMed

Tuna, Burcu Kaya; Semiz-Oysu, Aslıhan; Pekar, Bilhan; Bukte, Yasar; Hayirlioglu, Alper

2014-01-01

The relationship of patellofemoral congruency with chondromalacia patellae (CP) was retrospectively evaluated. Lateral patellar tilt angle (LPTA), sulcus angle (SA), trochlear depth (TD), and patella angle (PA) were measured at 301 knee magnetic resonance images and compared between groups with and without CP. In the CP group, LPTA and TD were significantly low (P<.01), SA was high (P<.01), while PA showed no difference (P>.05). The parameters were also compared between groups with mild and severe CP, and no significant difference was found (P>.05). Our results demonstrate that patellar tilt and trochlear dysplasia are related to the presence but not the degree of CP. Copyright © 2014 Elsevier Inc. All rights reserved.

Chondromalacia patellae treated by warming needle and rehabilitation training.

PubMed

Qiu, Ling; Zhang, Min; Zhang, Ji; Gao, Le-Nv; Chen, Da-wei; Liu, Jun; She, Jia-yi; Wang, Ling; Yu, Jin-yan; Huang, Le-ping; Bai, Yang

2009-06-01

To observe the effect of warming needle combined with rehabilitation training on chondromalacia patellae in a randomized controlled trial. The 92 cases were randomly divided into a treatment group treated by warming needle plus rehabilitation training (47 cases) and a control group treated by medication plus rehabilitation training (45 cases), and the therapeutic effect was compared after 20 sessions. The pain was relieved more obviously in the treatment group than in the control group (P < 0.05), and the total effective rate was 91.8% and 71.1% respectively (P < 0.01). Warming needle plus rehabilitation training was superior in the therapeutic effect and duration of producing relief of pain to medication plus rehabilitation training in treating chondromalacia patellae.

Evaluation of the isometry of different points of the patella and femur for medial patellofemoral ligament reconstruction.

PubMed

Gobbi, Riccardo Gomes; Pereira, César Augusto Martins; Sadigursky, David; Demange, Marco Kawamura; Tírico, Luis Eduardo Passarelli; Pécora, José Ricardo; Camanho, Gilberto Luis

2016-10-01

The location of patellar and femoral fixation of the graft in medial patellofemoral ligament reconstructions has been widely discussed. This study aimed to assess the distances between different patellar and femoral fixation points to identify the least anisometric pairs of points. Ten cadaver knees were attached to an apparatus that simulated an active range of motion of 120°, with three metallic markers fixed onto the medial side of the patella, and seven markings onto the medial epicondyle. The examined points included the proximal patella pole (1), the patellar center (3), the midpoint between points 1 and 3 (2), a point directly on the epicondyle (6), points 5mm anterior (5) and posterior (7) to the epicondyle, points 5mm anterior to point 5 (4) and 5mm posterior to point 7 (8), and points 5mm proximal (9) and distal (10) to the epicondyle. The distances between patella and femur points were measured by a photogrammetry system at 15° intervals. The pair of points that exhibited the lowest average variability in distance, and hence was the most isometric, was the patella center combined with the anterior to the medial femoral epicondyle. The pairs of points that exhibited the highest average variability in distance, and hence were the least isometric, were the ones located distal or posterior to the medial femoral epicondyle, with less influence by the patellar location. Surgeons should avoid positioning the graft distally or posterior to the epicondyle due to the increase in anisometry. Copyright © 2016 Elsevier Ltd. All rights reserved.

Should the position of the patellar component replicate the vertical median ridge of the native patella?

PubMed

Lee, Rae Hyeong; Jeong, Hae Won; Lee, Jin Kyu; Choi, Choong Hyeok

2017-01-01

In total knee arthroplasty (TKA), the position of the patellar component can affect patellar tracking. However, the patellar component cannot always replicate the original high point of the patella because of anatomical variance. This study investigated whether altering the highest point of the patella can affect outcomes of primary TKA, especially in patients having a patella with a far-medialized median ridge. A retrospective review was performed for 177 knees (143 patients) treated with primary TKA between July 2011 and March 2014. Group 1 (34 knees) had the patellar component displaced over three millimeters from the median ridge, while Group 2 (143 knees) had the patellar component placed on the original median ridge position. The one-year follow-up outcomes were reviewed, including: patellar tilt angle, Knee Society Score, Feller Patellar Score, and modified Kujala Anterior Knee Pain Score. Mean (±standard deviation) displacement of the patellar component in Group 1 was 3.97±0.97mm lateral to the original position of the median ridge, with a significant decrease in lateral patellar tilt angle (P<0.001). Lateral patellar tilt showed a positive correlation with the medialization of the patellar component (P<0.001, r=0.401). Ability to rise from a chair was better in Group 1 (P=0.025). There were no other between-group differences in other clinical outcomes. There should be no need for the patellar component to replicate the original highest point of the native patella in primary TKA. Copyright © 2016 Elsevier B.V. All rights reserved.

Non-metallic implant for patellar fracture fixation: A systematic review.

PubMed

Camarda, Lawrence; Morello, Salvatore; Balistreri, Francesco; D'Arienzo, Antonio; D'Arienzo, Michele

2016-08-01

Despite good clinical outcome proposals, there has been relatively little published regarding the use of non-metallic implant for patellar fracture fixation. The purpose of the study was to perform a systematic literature review to summarize and evaluate the clinical studies that described techniques for treating patella fractures using non-metallic implants. A comprehensive literature search was systematically performed to evaluate all studies included in the literature until November 2015. The following search terms were used: patellar fracture, patella suture, patella absorbable, patella screw, patella cerclage. Two investigators independently reviewed all abstracts and the selection of these abstracts was then performed based on inclusion and/or exclusion criteria. A total of 9 studies involving 123 patients were included. Patients had a mean age of 33.7 years and were followed up for a mean of 18.9 months. The most common method for fracture fixations included the use of suture material. Good clinical outcomes were reported among all studies. Thirteen patients (10.5%) presented complications, while 4 patients (3.2%) required additional surgery for implant removal. There is a paucity of literature focused on the use of non-metallic implant for patellar fracture fixation. However, this systematic review showed that non-metallic implants are able to deliver good clinical outcomes reducing the rate of surgical complications and re-operation. These results may assist surgeons in choosing to use alternative material such as sutures to incorporate into their routine practice or to consider it, in order to reduce the rate of re-operation. Copyright © 2016 Elsevier Ltd. All rights reserved.

A new MRI grading system for chondromalacia patellae.

PubMed

Özgen, Ali; Taşdelen, Neslihan; Fırat, Zeynep

2017-04-01

Background Chondromalacia patellae is a very common disorder. Although magnetic resonance imaging (MRI) is widely used to investigate patellar cartilage lesions, there is no descriptive MRI-based grading system for chondromalacia patellae. Purpose To propose a new MRI grading system for chondromalacia patellae with corresponding high resolution images which might be useful in precisely reporting and comparing knee examinations in routine daily practice and used in predicting natural course and clinical outcome of the patellar cartilage lesions. Material and Methods High resolution fat-saturated proton density (FS PD) images in the axial plane with corresponding T2 mapping images were reviewed. A detailed MRI grading system covering the deficiencies of the existing gradings has been set and presented on these images. Two experienced observers blinded to clinical data examined 44 knee MR images and evaluated patellar cartilage changes according to the proposed grading system. Inter- and intra-rater validity testing using kappa statistics were calculated. Results A descriptive and detailed grading system with corresponding FS PD and T2 mapping images has been presented. Inter-rater agreement was 0.80 (95% confidence interval [CI], 0.71-0.89). Intra-rater agreements were 0.83 (95% CI, 0.74-0.91) for observer A and 0.79 (95% CI, 0.70-0.88) for observer B (k-values). Conclusion We present a new MRI grading system for chondromalacia patellae with corresponding images and good inter- and intra-rater agreement which might be useful in reporting and comparing knee MRI examinations in daily practice and may also have the potential for using more precisely predicting prognosis and clinical outcome of the patients.

[Patellar bone deficiency in revision total knee arthroplasty].

PubMed

Kloiber, J; Goldenitsch, E; Ritschl, P

2016-05-01

Patellar bone deficiency in revision total knee arthroplasty (TKA) determines the surgical procedure. Different reconstructive and ablative techniques, dependent on the remaining bone stock, are described. The primary patella implant can be retained in up to 50 % of revision situations. Reasons for replacement are aseptic and septic loosening, implant failure, expanding osteolysis, maltracking of the patella and "metal-backed" prosthesis. The aim of the reconstruction is the stable fixation and proper tracking of the implant by restoring the extensor mechanism. Dependent on the extent of bone loss and the availability of a patellar rim, the following surgical procedures are recommended. When the remaining bone thickness is 10 mm or more: implantation of a polyethylene "onlay-type" patella; when it is between 6-9 mm and there is an intact patellar rim: reconstruction with a biconvex "inlay-type" patella implant, where the biconvex shape replaces the bone defect partially. When there is deficient bone stock (less than 6 mm) or no cortical patellar rim then augmenting procedures with autologous spongiosa and procedures such as "impaction bone grafting", "trabecular metal" prosthesis, where the trabecular part of the implant serves as the base for the cemented polyethylene button, "gull-wing" osteotomy, which is an adapting and configuring technique of osteotomy; and in exceptional cases patelloplasty or patellectomy are used. Regarding the importance of the patellar component in biomechanics of the joint and function of the extensor mechanism, the reconstruction of the patella should be the primary aim. Patelloplasty or patellectomy should be avoided.

Adult patient with Becker dystrophy undergoing orthopedic surgery: an anesthesia challenge.

PubMed

Parish, Masoud; Farzin, Haleh

2018-01-01

Muscular dystrophies are considered to be a series of neuromuscular diseases with genetic causes and are characterized by progressive muscle weakness and degeneration of the skeletal muscle. The case of an adult man with Becker dystrophy referred for repair of the patella tendon tearing and patella fracture is described. He underwent successful surgery using total intravenous anesthesia without any complications.

[Histomorphological analyse of accelerating the fibrocartilage layer repair of patella-patellar tendon junction in rabbits by low intensity pulsed ultrasound stimulation].

PubMed

Zhang, Baoliang; Lü, Hongbin; Hu, Jianzhong; Xu, Daqi; Zhou, Jingyong; Wang, Ye

2013-08-01

To analyse the effect of low intensity pulsed ultrasound stimulation (LIPUS) on accelerating the fibrocartilage layer repair of patella-patellar tendon junction. A total of 60 mature female New Zealand white rabbits undergoing standard partial patellectomy were divided into 2 groups randomly. The control group was given comfort treatment and the treatment group was given LIPUS treatment starting from day 3 to the end of week 6 postoperatively. The scheduled time points of animal euthanization would be at week 6, week 12 and week 18 postoperatively. The patella-patellar tendon (PPT) complex would be harvested and cut into sections after decalcification for H&E staining, Safranine o/fast green staining. The thickness and gray value of fibrocartilage layer were analyzed by SANO Microscope Partner image analyzer. At week 6, week 12 and week 18 postoperatively, the fibrocartilage layer in the treatment group was significantly thicker than that in the control group (P<0.01), and the gray value of fibrocartilage layer was significantly smaller than that in the control group (P<0.01). LIPUS helps to accelerate the fibrocartilage layer repair of patella-patellar tendon junction in rabbit models.

Neglected bilateral congenital dislocation of the patella.

PubMed

Tokgöz, Mehmet Ali; Çavuşoğlu, Ali Turgay; Ayanoğlu, Tacettin; Elma, Tarık; Vural, Abdurrahman

2017-08-01

Congenital dislocation of the patella is a disorder that presents with dysfunction in extensor mechanism. Although congenital dislocation of the patella mostly occurs in children with genetic disorders, it may also occur in totally healthy children, despite rarely. In this article, we report a 16-year-old male patient who referred to our clinic with complaints of gait disturbance, frequent falls, and muscular weakness in lower extremity. The patient had no complaints during walking, but had difficulty in running and walking up and down the stairs. It was observed that the range of motion of the knee joint was completely painless and the quadriceps muscle strength was evaluated as 3/5. An evaluation of computed tomography and magnetic resonance imaging results showed that the patella was dislocated. It became clear with magnetic resonance imaging that extensor mechanism was continuous but patellar tendon was not attached to its anatomical position. Surgical treatment was not planned because the patient did not describe any pain complaint and there was no limitation of joint movement, he could walk without support and without device and also refused to be operated. The choice of treatment should be based on the patient's preference, and pain and functional status.

Bone density in patients with chondromalacia patella.

PubMed

Salehi, Iraj; Khazaeli, Shabnam; Hatami, Parta; Malekpour, Mahdi

2010-06-01

Chondromalacia of the patella is the most common cause of anterior knee pain in young women. The etiology of the disease is not well-understood but the initial lesion is a disorganization of collagenous structures. Since the disease is proposed to be due to generalized constitutional disturbance, we postulated that bony structures could also be involved. To investigate this hypothesis we measured the bone density of 286 patients with the diagnosis of chondromalacia of the patella during a 4-year period using dual energy X-ray absorptiometry (DXA) method. We found a significant number of patients having low bone densities. This problem was more pronounced in men and in younger age groups. We suggest base-line bone density evaluation in all patients, treatment of osteopenia or osteoporosis in select patients and regular follow-ups using DXA.

Patella Fracture Fixation with Suture and Wire: you Reap what you Sew

PubMed Central

Egol, Kenneth; Howard, Daniel; Monroy, Alexa; Crespo, Alexander; Tejwani, Nirmal; Davidovitch, Roy

2014-01-01

Introduction Operative fixation of displaced inferior pole patella fractures has now become the standard of care. This study aims to quantify clinical, radiographic and functional outcomes, as well as identify complications in a cohort of patients treated with non-absorbable braided suture fixation for inferior pole patellar fractures. These patients were then compared to a control group of patients treated for mid-pole fractures with K-wires or cannulated screws with tension band wiring. Methods In this IRB approved study, we identified a cohort of patients who were diagnosed and treated surgically for a displaced patella fracture. Demographic, injury, and surgical information were recorded. All patients were treated with a standard surgical technique utilizing non-absorbable braided suture woven through the patellar tendon and placed through drill holes to achieve reduction and fracture fixation. All patients were treated with a similar post-operative protocol and followed up at standard intervals. Data were collected concurrently at follow up visits. For purpose of comparison, we identified a control cohort with middle third patella fractures treated with either k-wires or cannulated screws and tension band technique. Patients were followed by the treating surgeon at regular follow-up intervals. Outcomes included self-reported function and knee range of motion compared to the uninjured side. Results Forty-nine patients with 49 patella fractures identified retrospectively were treated over 9 years. This cohort consisted of 31 females (63.3%) and 18 males (36.7%) with an average age of 57.1 years (range 26 - 88 years). Patients had an average BMI of 26.48 (range 19 - 44.08). Thirteen patients with inferior pole fractures underwent suture fixation and 36 patients with mid-pole fractures underwent tension band fixation (K-wire or cannulated screws with tension band). In the suture cohort, one fracture failed open repair (7.6%), which was revised again with sutures and progressed to union. Of the 36 fractures repaired with a tension band fixation, 11 underwent secondary surgery due to hardware pain or fixation failure (30.6%). At one year, no difference was seen in knee range of motion between cohorts. All fractures healed radiographically. Those patients who required reoperation or removal of hardware had significantly diminished range of motion about their injured knee (p > 0.005). Conclusions Patients who sustain inferior pole patella fractures have limited options for fracture fixation. Suture repair is clinically acceptable, yielding similar results to patella fractures repaired with metal implants. Importantly, patients undergoing suture repair appear to have fewer hardware related postoperative complications than those receiving wire fixation for midpole fractures. PMID:25328461

Sonography on injury of the medial patellofemoral ligament after acute traumatic lateral patellar dislocation: Injury patterns and correlation analysis with injury of articular cartilage of the inferomedial patella.

PubMed

Zhang, Guang-Ying; Zheng, Lei; Shi, Hao; Qu, Su-Hui; Ding, Hong-Yu

2013-12-01

The purpose of this study was to investigate the accuracy of high-frequency ultrasonography in the diagnosis of injuries of medial patellofemoral ligaments (MPFLs), analyse the characteristics of MPFL injury and correlations between injury of the MPFL and articular cartilage of the inferomedial patella in patients with acute traumatic lateral patellar dislocation. High-frequency sonographic images of 49 patients with acute traumatic lateral patellar dislocations treated surgically were reviewed. The χ(2) tests were performed for statistical analysis. Twenty-eight cases of complete MPFL tear and 21 cases of partial MPFL tear were identified in operation, with 27 cases of MPFL tear located at their femoral attachment, 21 cases of tear at the patellar attachment and one case of midsubstance tear. The diagnostic accuracy of sonography regarding partial MPFL tear and complete MPFL tear was 89.8% and 89.8%. Among the patients with MPFL tear at the patellar attachment, eight and six cases were concomitant with chondral and osteochondral lesions in the inferomedial patella, respectively, in contrast to nine and six cases in patients with MPFL tear at the femoral attachment, respectively. There was no significant difference between the two locations described above regarding the prevalence rates of chondral or osteochondral lesions of the inferomedial patella (P=0.732, P=0.614). Among the patients with complete MPFL tear, 12 and 10 cases were concomitant with chondral and osteochondral lesions in the inferomedial patella, respectively, while six and two cases were concomitant with partial MPFL tear. There was no significant difference between the two types of injuries discussed above on the prevalence rates of chondral lesions of the inferomedial patella (P=0.305), but the prevalence rate of osteochondral lesions between the two types of injuries discussed above was statistically different (P=0.035). The MPFL is most easily injured at the femoral attachment, secondly at the patellar attachment. High-frequency ultrasonography is an accurate method in the diagnosis of an MPFL tear. There are neither significant differences on the prevalence rates of chondral or osteochondral lesions of the inferomedial patella between locations of MPFL injuries, nor significant difference on the prevalence rates of chondral lesions between MPFL injury types; but the complete MPFL tear is more often concomitant with inferomedial patellar osteochondral lesions than the partial MPFL tear. Copyright © 2013 Elsevier Ltd. All rights reserved.

Patella fracture fixation with suture and wire: you reap what you sew.

PubMed

Egol, Kenneth; Howard, Daniel; Monroy, Alexa; Crespo, Alexander; Tejwani, Nirmal; Davidovitch, Roy

2014-01-01

Operative fixation of displaced inferior pole patella fractures has now become the standard of care. This study aims to quantify clinical, radiographic and functional outcomes, as well as identify complications in a cohort of patients treated with non-absorbable braided suture fixation for inferior pole patellar fractures. These patients were then compared to a control group of patients treated for mid-pole fractures with K-wires or cannulated screws with tension band wiring. In this IRB approved study, we identified a cohort of patients who were diagnosed and treated surgically for a displaced patella fracture. Demographic, injury, and surgical information were recorded. All patients were treated with a standard surgical technique utilizing non-absorbable braided suture woven through the patellar tendon and placed through drill holes to achieve reduction and fracture fixation. All patients were treated with a similar post-operative protocol and followed up at standard intervals. Data were collected concurrently at follow up visits. For purpose of comparison, we identified a control cohort with middle third patella fractures treated with either k-wires or cannulated screws and tension band technique. Patients were followed by the treating surgeon at regular follow-up intervals. Outcomes included self-reported function and knee range of motion compared to the uninjured side. Forty-nine patients with 49 patella fractures identified retrospectively were treated over 9 years. This cohort consisted of 31 females (63.3%) and 18 males (36.7%) with an average age of 57.1 years (range 26-88 years). Patients had an average BMI of 26.48 (range 19-44.08). Thirteen patients with inferior pole fractures underwent suture fixation and 36 patients with mid-pole fractures underwent tension band fixation (K-wire or cannulated screws with tension band). In the suture cohort, one fracture failed open repair (7.6%), which was revised again with sutures and progressed to union. Of the 36 fractures repaired with a tension band fixation, 11 underwent secondary surgery due to hardware pain or fixation failure (30.6%). At one year, no difference was seen in knee range of motion between cohorts. All fractures healed radiographically. Those patients who required reoperation or removal of hardware had significantly diminished range of motion about their injured knee (p > 0.005). Patients who sustain inferior pole patella fractures have limited options for fracture fixation. Suture repair is clinically acceptable, yielding similar results to patella fractures repaired with metal implants. Importantly, patients undergoing suture repair appear to have fewer hardware related postoperative complications than those receiving wire fixation for midpole fractures.

Long-term clinical and radiographic outcome of patello-femoral realignment procedures: a minimum of 15-year follow-up.

PubMed

Vivod, Gregor; Verdonk, Peter; Drobnič, Matej

2014-11-01

A retrospective single-centre study was focused on the long-term outcome after different patello-femoral (PF) realignment procedures. Thirty-nine patients treated for recurrent PF instability were examined after a mean post-operative time of 22.5 years. Their 78 knees were divided into: non-operated knees (NON-OPERATED)-N = 24, isolated proximal procedures (PROXIMAL)-N = 22, isolated distal procedures (DISTAL)-N = 10, and combined procedures (COMBINED)-N = 22. PF-related medical history together with clinical, subjective (KOOS and Kujala scores), and radiographic (Caton-Deschamps PF height index, Kellgren-Lawrence scale for tibio-femoral OA, and Iwano classification for PF OA) evaluation was conducted. PF re-dislocation rate was comparable between PROXIMAL (36%), DISTAL (20%), and COMBINED (32%). Isolated proximal procedures revealed less central patella positions (PROXIMAL 64%; DISTAL 90%; COMBINED 95%) and more frequent PF apprehension test (PROXIMAL 82%; DISTAL 40%, COMBINED 50%). KOOS and Kujala scores were similar in all three surgical subgroups, but significantly lower than in NON-OPERATED. Patellas were positioned lower after DISTAL, 0.8 (0.5-1.0) or COMBINED, 0.9 (0.4-1.3). Kellgren-Lawrence scores ≥2 were found in 42% NON-OPERATED, 37% PROXIMAL, 70% DISTAL, and 59% COMBINED, whereas Iwano classification ≥2 was confirmed in 46% NON-OPERATED, 64% PROXIMAL, 80% DISTAL, and 86% COMBINED. High PF re-dislocation rates together with a very high incidence of PF OA indicate that PF realignment strategies used traditionally had failed to reach their long-term expectations. The transfer of tibial tuberosity resulted in more constrained PF joints than isolated proximal procedures which allowed for more residual PF instability. Distal procedures additionally increased the likelihood for tibio-femoral OA. III.

Osteochondritis dissecans of the patella in a XVII century player of the Florentine historic kickball.

PubMed

Lippi, Donatella; Matucci-Cerinic, Marco; Villari, Natale; Fornaciari, Gino; Mascalchi, Mario

2010-03-01

We report a case of osteochondritis dissecans in the patella of Francesco de' Medici, Prince of Capistrano, who lived from 1594 to 1614. He was known to play Florentine kick ball, a precursor of Rugby and American football, and speculate that trauma from this activity may have led to the lesion. Copyright 2009 Elsevier B.V. All rights reserved.

The ''hot'' patella

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kipper, M.S.; Alazraki, N.P.; Feiglin, D.H.

1982-01-01

Increased patellar uptake on bone scans is seen quite commonly but the possible or probable etiologies of this finding have not been previously well described. A review of 100 consecutive bone scans showed that the incidence of bilateral ''hot'' patellae is 15%. Identified etiologies include osteoarthritic degenerative disease (35%), fracture, possible metastatic disease, bursitis, Paget's disease, and osteomyelitis. The value of careful history, physical examination, and radiographs is stressed.

Seasonality in the Western Mediterranean During the Last Glacial From Paired Oxygen Isotopes and Mg/Ca in Limpet Shells

NASA Astrophysics Data System (ADS)

Ferguson, J. E.; Henderson, G. M.; Fa, D.; Finlayson, C.

2008-12-01

Molluscs have shown great potential to act as seasonal-resolution archives of sea-surface temperatures (SST) at mid to high latitudes, outside the range of tropical surface corals. Seasonal resolution climate records from higher latitudes are important to allow investigation of the role of seasonality in controlling mean climate on diverse timescales, and of the evolution of climate systems such as the North Atlantic Oscillation. Long sequences of intertidal mollusc shells are difficult to find due to sea level fluctuations over glacial- interglacial periods. This study makes use of Patella shells collected by Neanderthals and humans and transported inland to caves on Gibraltar over at least the last 120 kyrs. Some 30 fossil Patella shells were selected from several hundred excavated from Gorham's and Vanguard Caves at Gibraltar. Oxygen isotope analysis of micromilled samples of modern Patella shells from the Gibraltar coastline demonstrate that the shells accurately record absolute SSTs and capture more than 80% of the full seasonal range. Analysis of fossil Patella shells, dated using 14C, provides records of the change in absolute SST and seasonality during the last glacial. Paired Mg/Ca ratios of micromilled samples in modern Patella shells follow a consistent positive relationship with SST providing an independent paleothermometer, analogous with coral Sr/Ca. Applying this Mg/Ca-SST relationship to fossil Patella shells allows the independent reconstruction of the absolute values and range of SSTs and the reconstruction of seawater δ18O for the western Mediterranean. Results show a cooling of glacial summer SSTs from 36 kyr BP to the LGM with maximum cooling of glacial summer SSTs of 7.5 °C relative to modern. In contrast, winter SSTs show greater variability on millennial timescales with a maximum cooling of up to 10 °C. SST seasonality is therefore extended due to greater winter cooling but SST seasonality is highly variable as a result of large fluctuation in the extent of winter cooling. These results contrast with GCM model estimates of SST values and seasonality during the glacial.

A Novel Biological Approach to Treat Chondromalacia Patellae

PubMed Central

Lee, Sang Hee

2013-01-01

Mesenchymal stem cells from several sources (bone marrow, synovial tissue, cord blood, and adipose tissue) can differentiate into variable parts (bones, cartilage, muscle, and adipose tissue), representing a promising new therapy in regenerative medicine. In animal models, mesenchymal stem cells have been used successfully to regenerate cartilage and bones. However, there have been no follow-up studies on humans treated with adipose-tissue-derived stem cells (ADSCs) for the chondromalacia patellae. To obtain ADSCs, lipoaspirates were obtained from lower abdominal subcutaneous adipose tissue. The stromal vascular fraction was separated from the lipoaspirates by centrifugation after treatment with collagenase. The stem-cell-containing stromal vascular fraction was mixed with calcium chloride-activated platelet rich plasma and hyaluronic acid, and this ADSCs mixture was then injected under ultrasonic guidance into the retro-patellar joints of all three patients. Patients were subjected to pre- and post-treatment magnetic resonance imaging (MRI) scans. Pre- and post-treatment subjective pain scores and physical therapy assessments measured clinical changes. One month after the injection of autologous ADSCs, each patient's pain improved 50–70%. Three months after the treatment, the patients' pain improved 80–90%. The pain improvement persisted over 1 year, confirmed by telephone follow ups. Also, all three patients did not report any serious side effects. The repeated magnetic resonance imaging scans at three months showed improvement of the damaged tissues (softened cartilages) on the patellae-femoral joints. In patients with chondromalacia patellae who have continuous anterior knee pain, percutaneous injection of autologous ADSCs may play an important role in the restoration of the damaged tissues (softened cartilages). Thus, ADSCs treatment presents a glimpse of a new promising, effective, safe, and non-surgical method of treatment for chondromalacia patellae. PMID:23700485

A novel biological approach to treat chondromalacia patellae.

PubMed

Pak, Jaewoo; Lee, Jung Hun; Lee, Sang Hee

2013-01-01

Mesenchymal stem cells from several sources (bone marrow, synovial tissue, cord blood, and adipose tissue) can differentiate into variable parts (bones, cartilage, muscle, and adipose tissue), representing a promising new therapy in regenerative medicine. In animal models, mesenchymal stem cells have been used successfully to regenerate cartilage and bones. However, there have been no follow-up studies on humans treated with adipose-tissue-derived stem cells (ADSCs) for the chondromalacia patellae. To obtain ADSCs, lipoaspirates were obtained from lower abdominal subcutaneous adipose tissue. The stromal vascular fraction was separated from the lipoaspirates by centrifugation after treatment with collagenase. The stem-cell-containing stromal vascular fraction was mixed with calcium chloride-activated platelet rich plasma and hyaluronic acid, and this ADSCs mixture was then injected under ultrasonic guidance into the retro-patellar joints of all three patients. Patients were subjected to pre- and post-treatment magnetic resonance imaging (MRI) scans. Pre- and post-treatment subjective pain scores and physical therapy assessments measured clinical changes. One month after the injection of autologous ADSCs, each patient's pain improved 50-70%. Three months after the treatment, the patients' pain improved 80-90%. The pain improvement persisted over 1 year, confirmed by telephone follow ups. Also, all three patients did not report any serious side effects. The repeated magnetic resonance imaging scans at three months showed improvement of the damaged tissues (softened cartilages) on the patellae-femoral joints. In patients with chondromalacia patellae who have continuous anterior knee pain, percutaneous injection of autologous ADSCs may play an important role in the restoration of the damaged tissues (softened cartilages). Thus, ADSCs treatment presents a glimpse of a new promising, effective, safe, and non-surgical method of treatment for chondromalacia patellae.

Editorial Commentary: Which Came First, the Patella or the Trochlea? Morphological Relationships in Patients With Patellar Instability.

PubMed

Tanaka, Miho J

2018-06-01

Trochlear dysplasia and patella alta are known risk factors for patellar instability, yet the relation between the two has not been well understood. Morphologic abnormalities such as trochlear dysplasia and patella alta are known to alter patellofemoral kinematics, whereas altered contact pressures, in turn, have been associated with the development of trochlear dysplasia. As our current treatments aim to correct these deformities through increasingly complex procedures such as trochleoplasty and tuberosity distalization, we should consider this relation and the potential for changing the course of developing such morphologic abnormalities earlier in life. Further studies on the developmental cause of this disorder may help guide future treatments in the management of patellar instability. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Study of metals concentration levels in Patella piperata throughout the Canary Islands, Spain.

PubMed

Bergasa, Oscar; Ramírez, Rubén; Collado, Cayetano; Hernández-Brito, J Joaquín; Gelado-Caballero, María Dolores; Rodríguez-Somozas, María; Haroun, Ricardo J

2007-04-01

In order to assess the extent of metal contamination at rocky shores of the Canarian Archipelago, metal concentrations have been measured in Patella piperata (Gould, 1846), using the standard atomic absorption spectrophotometer technique. Ranges of elements concentrations measured (in microg g(-1)) found in the biota were: Cd (0.36 +/- 0.26 microg g(-1) dry wt.), Cu (2.05 +/- 0.91 dry wt.), Pb (1.57 +/- 1.14 microg g(-1)dry wt.) and Zn (10.37 +/- 4.60 microg g(-1) dry wt.). Variation in metal concentrations in Patella, was tested by using non-parametric statistical methods. Cd content had a maximum in the Archipelago Chinijo, northward of Lanzarote Island. The metal concentrations recorded at the clean stations may be considered carefully if they are used like background levels.

The Anatomy of the Medial Patellofemoral Complex.

PubMed

Tanaka, Miho J

2017-06-01

The term "medial patellofemoral complex" (MPFC) was proposed to describe the static medial stabilizer of the patella, typically referred to as the medial patellofemoral ligament. In light of our increasing understanding of the attachment of its fibers to the quadriceps tendon in addition to the patella, the term MPFC is used in this article. The purpose of this article is to describe and discuss the anatomy of the MPFC.

Comminuted inferior pole fracture of patella can be successfully treated with rim-plate-augmented separate vertical wiring.

PubMed

Cho, Jae-Woo; Kim, Jinil; Cho, Won-Tae; Gujjar, Pranay H; Oh, Chang-Wug; Oh, Jong-Keon

2018-02-01

We present the surgical technique of rim-plate-augmented separate vertical wiring for comminuted inferior pole fracture of the patella and report the clinical outcomes. Between July 2013 and January 2016, 13 patients (7 male and 6 female) who were diagnosed with comminuted inferior pole fracture of the patella in preoperative computed tomography and underwent a minimum of 1 year of follow-up were enrolled in this study. Mean patient age was 57.7 years (range 28-72 years). All patients underwent open reduction and internal fixation by rim-plate-augmented separate vertical wiring. Bony union, complications, range of motion and Bostman score were the clinical outcomes. Bony union was achieved in all cases at an average of 10 weeks after surgery (range 8-12). There was no loss of reduction and fixative failure during follow-up. The average range of motion was 127° (range 120°-130°). The mean Bostman score at last follow-up was 29.6 points (range 27-30) and graded excellent in 12 patients. Rim-plate-augmented separate vertical wiring demonstrated secure fixation and favorable clinical outcomes. This study provides evidence for its effectiveness as a fixation method for treating displaced, comminuted inferior pole fracture of the patella.

Sleeve fracture of the adult patella: Case report and review of the literature.

PubMed

Xie, Linjun; Xu, Hong; Zhang, Lizhi; Xu, Rong; Guo, Yingkun

2017-08-01

The patellar fractures are common in adults, but rare in children. As a particular type of patellar fracture, however, sleeve fractures are almost always limited to children in the under 16's group. Herein, we report a rare case of a 19-year-old healthy adult female who presented sleeve fracture at the superior pole of the left patella. The clinical and radiological features are found including joint effusion, anterior tilt of the patella and a shell of bone lying proximally to the patella. Computed tomography and magnetic resonance imaging examination have been performed to further confirm the diagnosis of sleeve fracture, rupture of the quadriceps tendon and the cartilaginous injury. Under general anaesthesia, she underwent open surgical procedures for reconstituting anatomically the fracture and repairing the rupture of the quadriceps tendon. Six months after the operation, she could fully use her left knee without any pain and disability. Sleeve fractures of the patellar in adults are extremely rare, and our case is of interest for the first time occurring in healthy female adults. Our case report and literature review was aim to describe the clinic and imaging characteristics of superior pole sleeve fractures in adults, and highlight that physicians must be aware of this entity in adults so as to reduce misdiagnosis due to unfamiliarity.

Internal fixation of displaced inferior pole of the patella fractures using vertical wiring augmented with Krachow suturing.

PubMed

Oh, Hyoung-Keun; Choo, Suk-Kyu; Kim, Ji-Wan; Lee, Mark

2015-12-01

We present the surgical technique of separate vertical wiring for displaced inferior pole fractures of the patella combined with Krachow suture and report the surgical outcomes. Between September 2007 to May 2012, 11 consecutive patients (mean age, 54.6 years) with inferior pole fractures of the patella (AO/OTA 34-A1) were retrospectively enrolled in this study. Through longitudinal incision, all patients underwent open reduction and internal fixation by separate vertical wiring combined with Krackow suture. The range of motion, loss of fixation, and Bostman score were primary outcome measures. The union time was 10 weeks after surgery on average (range: 8-12). No patient had nonunion, loss of reduction and wire breakage. There was no case of wound problem and irritation from the implant. At final follow-up, the average range of motion arc was 129.4° (range: 120-140). The mean Bostman score at last follow-up was 29.6 points (range: 28-30) and graded excellent in all cases. Separate vertical wiring combined with Krackow suture for inferior pole fractures of the patella is a useful technique that is easy to perform and can provide stable fixation with excellent results in knee function. Copyright © 2015 Elsevier Ltd. All rights reserved.

[The optimization of chondromalacia patellae diagnosis by NMR tomography. The use of an apparatus for cartilage compression].

PubMed

König, H; Dinkelaker, F; Wolf, K J

1991-08-01

The aim of this study was to improve the MRI diagnosis of CMP, with special reference to the early stages and accurate staging. For this purpose, the retropatellar cartilage was examined by MRI while compression was carried out, using 21 patients and five normal controls. The compression was applied by means of a specially constructed device. Changes in cartilage thickness and signal intensity were evaluated quantitatively during FLASH and FISP sequences. In all patients the results of arthroscopies were available and in 12 patients, cartilage biopsies had been obtained. CMP stage I could be distinguished from normal cartilage by reduction in cartilage thickness and signal increase from the oedematous cartilage during compression. In CMP stages II/III, abnormal protein deposition of collagen type I could be demonstrated by its compressibility. In stages III and IV, the method does not add any significant additional information.

Ewing's sarcoma of the patella.

PubMed

Gorelik, Natalia; Dickson, Brendan C; Wunder, Jay S; Bleakney, Robert

2013-05-01

Ewing's sarcoma is a relatively rare malignancy, occurring mainly between 4 and 25 years of age. It usually arises from the pelvis, followed by the femur, tibia, and remainder of both the long bones of the extremities and flat bones of the axial skeleton. To the best of our knowledge, Ewing's sarcoma of the patella has never been reported previously. Patellar tumors occur infrequently and represent an uncommon etiology of anterior knee pain. We describe the rare case of a 41-year-old man who presented with a 3-4 month history of escalating right anterior knee pain and swelling. Imaging demonstrated an aggressive patellar tumor with an adjacent soft tissue mass. The diagnosis of Ewing's sarcoma was confirmed by pathology. Physicians should be aware of atypical locations for Ewing's sarcoma and, conversely, of rare tumors arising in the patella and accounting for anterior knee pain. Early recognition of such malignancies allows prompt initiation of treatment, hence improving prognosis.

[Patella fractures in knee arthroplasty].

PubMed

Roth, A; Ghanem, M; Fakler, J

2016-05-01

Periprosthetic patella fractures occur both with and without retropatellar joint replacement. A non-operative treatment yields satisfactory results with low morbidity. It can be applied in minimally displaced fractures that have an intact retropatellar component and an intact extensor mechanism, combined with an initial immobilization. The surgical treatment is associated with relatively poor results and with high complication rates. There was only minor improvement of functional results, no matter which surgical technique was used. Surgical intervention is still required in fractures with a loosening of the patellar component, considerable dislocations of fragments, and damage to or rupture of the extensor mechanism. In particular, type II fractures require repair of the extensor mechanism and the fracture or patellectomy. Type III fractures require a revision or resection of the patella, a patelloplasty or total patellectomy. In addition, early or late reconstruction using allograft to restore the extensor mechanism can be taken in consideration.

Patellofemoral anatomy and biomechanics: current concepts

PubMed Central

ZAFFAGNINI, STEFANO; DEJOUR, DAVID; GRASSI, ALBERTO; BONANZINGA, TOMMASO; MUCCIOLI, GIULIO MARIA MARCHEGGIANI; COLLE, FRANCESCA; RAGGI, FEDERICO; BENZI, ANDREA; MARCACCI, MAURILIO

2013-01-01

The patellofemoral joint, due to its particular bone anatomy and the numerous capsuloligamentous structures and muscles that act dynamically on the patella, is considered one of the most complex joints in the human body from the biomechanical point of view. The medial patellofemoral ligament (MPFL) has been demonstrated to contribute 60% of the force that opposes lateral displacement of the patella, and MPFL injury results in an approximately 50% reduction in the force needed to dislocate the patella laterally with the knee extended. For this reason, recent years have seen a growing interest in the study of this important anatomical structure, whose aponeurotic nature has thus been demonstrated. The MPFL acts as a restraint during motion, playing an active role under conditions of laterally applied stress, but an only marginal role during natural knee flexion. However, it remains extremely difficult to clearly define the anatomy of the MPFL and its relationships with other anatomical structures. PMID:25606512

Apparent Transition in the Human Height Distribution Caused by Age-Dependent Variation during Puberty Period

NASA Astrophysics Data System (ADS)

Iwata, Takaki; Yamazaki, Yoshihiro; Kuninaka, Hiroto

2013-08-01

In this study, we examine the validity of the transition of the human height distribution from the log-normal distribution to the normal distribution during puberty, as suggested in an earlier study [Kuninaka et al.: J. Phys. Soc. Jpn. 78 (2009) 125001]. Our data analysis reveals that, in late puberty, the variation in height decreases as children grow. Thus, the classification of a height dataset by age at this stage leads us to analyze a mixture of distributions with larger means and smaller variations. This mixture distribution has a negative skewness and is consequently closer to the normal distribution than to the log-normal distribution. The opposite case occurs in early puberty and the mixture distribution is positively skewed, which resembles the log-normal distribution rather than the normal distribution. Thus, this scenario mimics the transition during puberty. Additionally, our scenario is realized through a numerical simulation based on a statistical model. The present study does not support the transition suggested by the earlier study.

Sleeve fracture of the adult patella

PubMed Central

Xie, Linjun; Xu, Hong; Zhang, Lizhi; Xu, Rong; Guo, Yingkun

2017-01-01

Abstract Rationale: The patellar fractures are common in adults, but rare in children. As a particular type of patellar fracture, however, sleeve fractures are almost always limited to children in the under 16's group. Patient concerns: Herein, we report a rare case of a 19-year-old healthy adult female who presented sleeve fracture at the superior pole of the left patella. The clinical and radiological features are found including joint effusion, anterior tilt of the patella and a shell of bone lying proximally to the patella. Diagnoses: Computed tomography and magnetic resonance imaging examination have been performed to further confirm the diagnosis of sleeve fracture, rupture of the quadriceps tendon and the cartilaginous injury. Interventions: Under general anaesthesia, she underwent open surgical procedures for reconstituting anatomically the fracture and repairing the rupture of the quadriceps tendon. Outcomes: Six months after the operation, she could fully use her left knee without any pain and disability. Lessons: Sleeve fractures of the patellar in adults are extremely rare, and our case is of interest for the first time occurring in healthy female adults. Our case report and literature review was aim to describe the clinic and imaging characteristics of superior pole sleeve fractures in adults, and highlight that physicians must be aware of this entity in adults so as to reduce misdiagnosis due to unfamiliarity. PMID:28796028

Sex estimation from the patella in an African American population.

PubMed

Peckmann, Tanya R; Fisher, Brooke

2018-02-01

The skull and pelvis have been used for the estimation of sex for unknown human remains. However, in forensic cases where skeletal remains often exhibit postmortem damage and taphonomic changes the patella may be used for the estimation of sex as it is a preservationally favoured bone. The goal of the present research was to derive discriminant function equations from the patella for estimation of sex from an historic African American population. Six parameters were measured on 200 individuals (100 males and 100 females), ranging in age from 20 to 80 years old, from the Robert J. Terry Anatomical Skeleton Collection. The statistical analyses showed that all variables were sexually dimorphic. Discriminant function score equations were generated for use in sex estimation. The overall accuracy of sex classification ranged from 80.0% to 85.0% for the direct method and 80.0%-84.5% for the stepwise method. Overall, when the Spanish and Black South African discriminant functions were applied to the African American population they showed low accuracy rates for sexing the African American sample. However, when the White South African discriminant functions were applied to the African American sample they displayed high accuracy rates for sexing the African American population. The patella was shown to be accurate for sex estimation in the historic African American population. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Oxidized zirconium versus cobalt-chromium against the native patella in total knee arthroplasty: Patellofemoral outcomes.

PubMed

Matassi, Fabrizio; Paoli, Tommaso; Civinini, Roberto; Carulli, Christian; Innocenti, Massimo

2017-10-01

Oxidized zirconium (OxZr) has demonstrated excellent mechanical properties in vitro when used against articular cartilage; less coefficient of friction and less chondral damage have been found when compared with cobalt-chromium (CoCr) implants. However, controversy exists as to whether implants with a zirconium femoral component articulate safely with a native patella in total knee arthroplasty (TKA). To answer this question, the clinical and radiographic results were analysed from a group of patients who underwent a TKA with patella retention; the OxZr versus CoCr femoral components were compared. The present study prospectively evaluated 83 knees of 74 patients from 2009 to 2010. Each patient was evaluated clinically (visual analogue scale, Knee Society score, patellar score) and radiographically (long leg standing radiograph, anterior-posterior and latero-lateral projections, axial view of the patella) pre-operatively and postoperatively with a mean follow-up of 4.47years. The patellar tilt and shift, and progression of patellofemoral osteoarthritis were calculated with the axial view. There were no patient reported adverse reactions and none of the evaluated prostheses failed. Both the clinical and radiographic evaluations showed no statistically significant between-group differences. No adverse events were observed clinically or radiologically. These results justify pursuing the use of oxidized zirconium as an alternative bearing surface for a femoral component associated with patellar retention in TKA. Published by Elsevier B.V.

Experimental investigation of internal tides generated by finite-height topography

NASA Astrophysics Data System (ADS)

Wang, Shuya; Chen, Xu; Wang, Jinhu; Meng, Jing

2018-06-01

Internal tides generated by finite-height topography are investigated in the laboratory, and the particle image velocimetry (PIV) technique is applied to measure the velocity fields. The energy, energy flux, and vertical mode structure of the internal tides are calculated and analyzed. The experimental results indicate that the strength of the wave field is mainly affected by the normalized topography height. The rays radiated from the taller topography are wider than those radiated from the lower topography. Both the experimental and theoretical results indicate that the normalized energy and energy flux of the internal tides are mainly determined by the normalized topography height, and the increase of the two quantities follows a quadratic function, and they almost remain unchanged with different normalized frequencies except for higher frequency. The percentage of energy for mode-1 and mode-2 internal tides is determined not only by frequency but also by topography height. In addition, an "inherent normalized frequency" is observed in the experiment, at which the percentage of energy for mode 1 and mode 2 does not vary with topography height. The decay rate of internal tide energy in the near field and far field is also estimated, with average values of 36.5 and 7.5%, respectively.

Characterization of calcium and zinc spatial distributions at the fibrocartilage zone of bone-tendon junction by synchrotron radiation-based micro X-ray fluorescence analysis combined with backscattered electron imaging

NASA Astrophysics Data System (ADS)

Lu, Hongbin; Chen, Can; Wang, Zhanwen; Qu, Jin; Xu, Daqi; Wu, Tianding; Cao, Yong; Zhou, Jingyong; Zheng, Cheng; Hu, Jianzhong

2015-09-01

Tendon attaches to bone through a functionally graded fibrocartilage zone, including uncalcified fibrocartilage (UF), tidemark (TM) and calcified fibrocartilage (CF). This transition zone plays a pivotal role in relaxing load transfer between tendon and bone, and serves as a boundary between otherwise structurally and functionally distinct tissue types. Calcium and zinc are believed to play important roles in the normal growth, mineralization, and repair of the fibrocartilage zone of bone-tendon junction (BTJ). However, spatial distributions of calcium and zinc at the fibrocartilage zone of BTJ and their distribution-function relationship are not totally understood. Thus, synchrotron radiation-based micro X-ray fluorescence analysis (SR-μXRF) in combination with backscattered electron imaging (BEI) was employed to characterize the distributions of calcium and zinc at the fibrocartilage zone of rabbit patella-patellar tendon complex (PPTC). For the first time, the unique distributions of calcium and zinc at the fibrocartilage zone of the PPTC were clearly mapped by this method. The distributions of calcium and zinc at the fibrocartilage zone of the PPTC were inhomogeneous. A significant accumulation of zinc was exhibited in the transition region between UF and CF. The highest zinc content (3.17 times of that of patellar tendon) was found in the TM of fibrocartilage zone. The calcium content began to increase near the TM and increased exponentially across the calcified fibrocartilage region towards the patella. The highest calcium content (43.14 times of that of patellar tendon) was in the transitional zone of calcified fibrocartilage region and the patella, approximately 69 μm from the location with the highest zinc content. This study indicated, for the first time, that there is a differential distribution of calcium and zinc at the fibrocartilage zone of PPTC. These observations reveal new insights into region-dependent changes across the fibrocartilage zone of BTJ and will serve as critical benchmark parameters for current efforts in BTJ repair.

Patellofemoral Pressure Changes After Static and Dynamic Medial Patellofemoral Ligament Reconstructions.

PubMed

Rood, Akkie; Hannink, Gerjon; Lenting, Anke; Groenen, Karlijn; Koëter, Sander; Verdonschot, Nico; van Kampen, Albert

2015-10-01

Reconstructing the medial patellofemoral ligament (MPFL) has become a key procedure for stabilizing the patella. Different techniques to reconstruct the MPFL have been described: static techniques in which the graft is fixed rigidly to the bone or dynamic techniques with soft tissue fixation. Static MPFL reconstruction is most commonly used. However, dynamic reconstruction deforms more easily and presumably functions more like the native MPFL. The aim of the study was to evaluate the effect of the different MPFL fixation techniques on patellofemoral pressures compared with the native situation. The hypothesis was that dynamic reconstruction would result in patellofemoral pressures closer to those generated in an intact knee. Controlled laboratory study. Seven fresh-frozen knee specimens were tested in an in vitro knee joint loading apparatus. Tekscan pressure-sensitive films fixed to the retropatellar cartilage measured mean patellofemoral and peak pressures, contact area, and location of the center of force (COF) at fixed flexion angles from 0° to 110°. Four different conditions were tested: intact, dynamic, partial dynamic, and static MPFL reconstruction. Data were analyzed using linear mixed models. Static MPFL reconstruction resulted in higher peak and mean pressures from 60° to 110° of flexion (P < .001). There were no differences in pressure between the 2 different dynamic reconstructions and the intact situation (P > .05). The COF in the static reconstruction group moved more medially on the patella from 50° to 110° of flexion compared with the other conditions. The contact area showed no significant differences between the test conditions. After static MPFL reconstruction, the patellofemoral pressures in flexion angles from 60° to 110° were 3 to 5 times higher than those in the intact situation. The pressures after dynamic MPFL reconstruction were similar as compared with those in the intact situation, and therefore, dynamic MPFL reconstruction could be a safer option than static reconstruction for stabilizing the patella. This study showed that static MPFL reconstruction results in higher patellofemoral pressures and thus enhances the chance of osteoarthritis in the long term, while dynamic reconstruction results in more normal pressures. © 2015 The Author(s).

An Anatomic Study on Whether the Immature Patella is Centered on an Anteroposterior Radiograph.

PubMed

Kyriakedes, James C; Liu, Raymond W

2017-03-01

In the operating room, after first obtaining a proper lateral radiograph with the condyles superimposed, a 90-degree rotation of the intraoperative fluoroscopy unit does not always produce an anteroposterior (AP) image with the patella centered. The orthogonality of these 2 views has not been well determined in children. This study was comprised of a radiographic group (35 knees) and a cadaveric group (59 knees). Both cadaveric and clinical images were obtained by resting or positioning the femur with the posterior condyles overlapped, and then taking an orthogonal AP image. Centering of the patella was calculated and multiple regression analysis was performed to determine the relationship between patellar centering and age, sex, ethnicity, mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle (MPTA), and contralateral centering. Mean patellar centering, expressed as the lateral position of the patella with respect to the total condylar width, was 0.08±0.10 in the radiographic group and 0.06±0.03 in the cadaveric group. Positive (lateral) patellar centering in 1 knee had a statistically significant correlation with positive patellar centering in the contralateral knee in both the radiographs and the cadavers. In the radiographic group, there was a statistically significant correlation between femoral varus and valgus deformities and positive patellar centering. In the cadaveric group, there was a statistically significant correlation between tibial valgus and negative (medial) patellar centering. The patella in an immature knee is rarely perfectly centered on a true AP image, and is usually seated slightly laterally within the femoral condyles. Obtaining a true AP intraoperative radiograph is critical to analyzing and correcting valgus and varus deformities, and in the proper placement of implants. When addressing knee deformity one should consider obtaining an AP view orthogonal either to a perfect lateral of the knee or orthogonal to the flexion axis of the knee, particularly when evaluating distal femoral deformity.

The Diagnostic Value of the Clarke Sign in Assessing Chondromalacia Patella

PubMed Central

Doberstein, Scott T; Romeyn, Richard L; Reineke, David M

2008-01-01

Context: Various techniques have been described for assessing conditions that cause pain at the patellofemoral (PF) joint. The Clarke sign is one such test, but the diagnostic value of this test in assessing chondromalacia patella is unknown. Objective: To (1) investigate the diagnostic value of the Clarke sign in assessing the presence of chondromalacia patella using arthroscopic examination of the PF joint as the “gold standard,” and (2) provide a historical perspective of the Clarke sign as a clinical diagnostic test. Design: Validation study. Setting: All patients of one of the investigators who had knee pain or injuries unrelated to the patellofemoral joint and were scheduled for arthroscopic surgery were recruited for this study. Patients or Other Participants: A total of 106 otherwise healthy individuals with no history of patellofemoral pain or dysfunction volunteered. Main Outcome Measure(s): The Clarke sign was performed on the surgical knee by a single investigator in the clinic before surgery. A positive test was indicated by the presence of pain sufficient to prevent the patient from maintaining a quadriceps muscle contraction against manual resistance for longer than 2 seconds. The preoperative result was compared with visual evidence of chondromalacia patella during arthroscopy. Results: Sensitivity was 0.39, specificity was 0.67, likelihood ratio for a positive test was 1.18, likelihood ratio for a negative test was 0.91, positive predictive value was 0.25, and negative predictive value was 0.80. Conclusions: Diagnostic validity values for the use of the Clarke sign in assessing chondromalacia patella were unsatisfactory, supporting suggestions that it has poor diagnostic value as a clinical examination technique. Additionally, an extensive search of the available literature for the Clarke sign reveals multiple problems with the test, causing significant confusion for clinicians. Therefore, the use of the Clarke sign as a routine part of a knee examination is not beneficial, and its use should be discontinued. PMID:18345345

The diagnostic value of the Clarke sign in assessing chondromalacia patella.

PubMed

Doberstein, Scott T; Romeyn, Richard L; Reineke, David M

2008-01-01

Various techniques have been described for assessing conditions that cause pain at the patellofemoral (PF) joint. The Clarke sign is one such test, but the diagnostic value of this test in assessing chondromalacia patella is unknown. To (1) investigate the diagnostic value of the Clarke sign in assessing the presence of chondromalacia patella using arthroscopic examination of the PF joint as the "gold standard," and (2) provide a historical perspective of the Clarke sign as a clinical diagnostic test. Validation study. All patients of one of the investigators who had knee pain or injuries unrelated to the patellofemoral joint and were scheduled for arthroscopic surgery were recruited for this study. A total of 106 otherwise healthy individuals with no history of patellofemoral pain or dysfunction volunteered. The Clarke sign was performed on the surgical knee by a single investigator in the clinic before surgery. A positive test was indicated by the presence of pain sufficient to prevent the patient from maintaining a quadriceps muscle contraction against manual resistance for longer than 2 seconds. The preoperative result was compared with visual evidence of chondromalacia patella during arthroscopy. Sensitivity was 0.39, specificity was 0.67, likelihood ratio for a positive test was 1.18, likelihood ratio for a negative test was 0.91, positive predictive value was 0.25, and negative predictive value was 0.80. Diagnostic validity values for the use of the Clarke sign in assessing chondromalacia patella were unsatisfactory, supporting suggestions that it has poor diagnostic value as a clinical examination technique. Additionally, an extensive search of the available literature for the Clarke sign reveals multiple problems with the test, causing significant confusion for clinicians. Therefore, the use of the Clarke sign as a routine part of a knee examination is not beneficial, and its use should be discontinued.

INVESTIGATING THE EFFECTIVENESS OF KINESIO® TAPING SPACE CORRECTION METHOD IN HEALTHY ADULTS ON PATELLOFEMORAL JOINT AND SUBCUTANEOUS SPACE.

PubMed

Lyman, Katie J; Keister, Kassiann; Gange, Kara; Mellinger, Christopher D; Hanson, Thomas A

2017-04-01

Limited quantitative, physiological evidence exists regarding the effectiveness of Kinesio® Taping methods, particularly with respect to the potential ability to impact underlying physiological joint space and structures. To better understand the impact of these techniques, the underlying physiological processes must be investigated in addition to the examination of more subjective measures related to pain in unhealthy tissues. The purpose of this study was to determine whether the Kinesio® Taping Space Correction Method created a significant difference in patellofemoral joint space, as quantified by diagnostic ultrasound. Pre-test/post-test prospective cohort study. Thirty-two participants with bilaterally healthy knees and no past history of surgery took part in the study. For each participant, diagnostic ultrasound was utilized to collect three measurements: the patellofemoral joint space, the distance from the skin to the superficial patella, and distance from the skin to the patellar tendon. The Kinesio® Taping Space Correction Method was then applied. After a ten-minute waiting period in a non-weight bearing position, all three measurements were repeated. Each participant served as his or her own control. Paired t tests showed a statistically significant difference (mean difference = 1.1 mm, t [3,1]  = 2.823, p  = 0.008, g  = .465) between baseline and taped conditions in the space between the posterior surface of the patella to the medial femoral condyle. Neither the distance from the skin to the superficial patella nor the distance from the skin to the patellar tendon increased to a statistically significant degree. The application of the Kinesio® Taping Space Correction Method increases the patellofemoral joint space in healthy adults by increasing the distance between the patella and the medial femoral condyle, though it does not increase the distance from the skin to the superficial patella nor to the patellar tendon. 3.

Does patella resurfacing really matter? Pain and function in 972 patients after primary total knee arthroplasty

PubMed Central

Espehaug, Birgitte; Havelin, Leif Ivar; Vollset, Stein Emil; Furnes, Ove

2010-01-01

Background and purpose Resurfacing of the patella during primary total knee arthroplasty (TKA) is often recommended based on higher revision rates in non-resurfaced knees. As many of these revisions are insertions of a patella component due to pain, and since only patients with a non-resurfaced patella have the option of secondary resurfacing, we do not really know whether these patients have more pain and poorer function. The main purpose of the present paper was therefore to assess pain and function at least 2 years after surgery for unrevised primary non-resurfaced and resurfaced TKA, and secondary among prosthesis brands. Methods Information needed to calculate subscales from the knee injury and osteoarthritis outcome score (KOOS) was collected in a questionnaire given to 972 osteoarthritis patients with intact primary TKAs that had been reported to the Norwegian Arthroplasty Register. Pain and satisfaction on visual analog scales and improvement in EQ-5D index score ΔEQ-5D) were also used as outcomes. Outcomes were measured on a scale from 0 to 100 units (worst to best). To estimate differences in mean scores, we used multiple linear regression with adjustment for possible confounders. Results We did not observe any differences between resurfacing and non-resurfacing in any outcome, with estimated differences of ≤ 1.4 units and p-values of > 0.4. There was, however, a tendency of better results for the NexGen implant as compared to the reference brand AGC for symptoms (difference = 4.9, p = 0.05), pain (VAS) (difference = 8.3, p = 0.004), and satisfaction (VAS) (difference = 7.9, p = 0.02). However, none of these differences reached the stated level of minimal perceptible clinical difference. Interpretation Resurfacing of the patella has no clinical effect on pain and function after TKA. Differences between the brands investigated were small and they were assumed to be of minor importance. PMID:20158405

USER-FRIENDLY SOLAR OVENS FOR OUTDOOR AND INDOOR USE

EPA Science Inventory

Local Topography Effect on Plant Area Index Profile Calculation from Small Footprint Airborne Laser Scanning

NASA Astrophysics Data System (ADS)

Liu, J.; Wang, T.; Skidmore, A. K.; Heurich, M.

2016-12-01

The plant area index (PAI) profile is a quantitative description of how plants (including leaves and woody materials) are distributed vertically, as a function of height. PAI profiles can be used for many applications including biomass estimation, radiative transfer modelling, fire fuel modelling and wildlife habitat assessment. With airborne laser scanning (ALS), forest structure underneath the canopy surface can be detected. PAI profiles can be calculated through estimates of the vertically resolved gap fraction from ALS data. In this process, a gridding or aggregation step is often involved. Most current research neglects local topographic change, and utilizes a height normalization algorithm to achieve a local or relative height, implying a flat local terrain assumption inside the grid or aggregation area. However, in mountainous forest, this assumption is often not valid. Therefore, in this research, the local topographic effect on the PAI profile calculation was studied. Small footprint discrete multi-return ALS data was acquired over the Bavarian Forest National Park under leaf-off and leaf-on conditions. Ground truth data, including tree height, canopy cover, DBH as well as digital hemispherical photos, were collected in 30 plots. These plots covered a wide range of forest structure, plant species, local topography condition and understory coverage. PAI profiles were calculated both with and without height normalization. The difference between height normalized and non-normalized profiles were evaluated with the coefficient of variation of root mean squared difference (CV-RMSD). The derived metric PAI values from PAI profiles were also evaluated with ground truth PAI from the hemispherical photos. Results showed that change in local topography had significant effects on the PAI profile. The CV-RMSD between PAI profile results calculated with or without height normalization ranged from 24.5% to 163.9%. Height normalization (neglecting topography change) can lead to offsets in the height of plant material that could potentially cause large errors and uncertainty when used in applications utilizing absolute height such as radiative transfer modeling and fire fuel modelling. This research demonstrates that when calculating the PAI profile from ALS, local topography has to be taken into account.

Does disc space height of fused segment affect adjacent degeneration in ALIF? A finite element study.

PubMed

Tang, Shujie; Meng, Xueying

2011-01-01

The restoration of disc space height of fused segment is essential in anterior lumbar interbody fusion, while the disc space height in many cases decreased postoperatively, which may adversely aggravate the adjacent segmental degeneration. However, no literature available focused on the issue. A normal healthy finite element model of L3-5 and four anterior lumbar interbody fusion models with different disc space height of fused segment were developed. 800 N compressive loading plus 10 Nm moments simulating flexion, extension, lateral bending and axial rotation were imposed on L3 superior endplate. The intradiscal pressure, the intersegmental rotation, the tresca stress and contact force of facet joints in L3-4 were investigated. Anterior lumbar interbody fusion with severely decreased disc space height presented with the highest values of the four parameters, and the normal healthy model presented with the lowest values except, under extension, the contact force of facet joints in normal healthy model is higher than that in normal anterior lumbar interbody fusion model. With disc space height decrease, the values of parameters in each anterior lumbar interbody fusion model increase gradually. Anterior lumbar interbody fusion with decreased disc space height aggravate the adjacent segmental degeneration more adversely.

Metaphylogenomic and potential functionality of the limpet Patella pellucida's gastrointestinal tract microbiome.

PubMed

Dudek, Magda; Adams, Jessica; Swain, Martin; Hegarty, Matthew; Huws, Sharon; Gallagher, Joe

2014-10-20

This study investigated the microbial diversity associated with the digestive tract of the seaweed grazing marine limpet Patella pellucida. Using a modified indirect DNA extraction protocol and performing metagenomic profiling based on specific prokaryotic marker genes, the abundance of bacterial groups was identified from the analyzed metagenome. The members of three significantly abundant phyla of Proteobacteria, Firmicutes and Bacteroidetes were characterized through the literature and their predicted functions towards the host, as well as potential applications in the industrial environment assessed.

Osteochondrosis of the Superior Pole of the Patella: Two Cases with Histologic Correlation

PubMed Central

Tyler, Wakenda; McCarthy, Edward F

2002-01-01

Two cases of osteochondrosis of the superior pole of the patella are reported with histologic findings. Both patients were young girls; one had mild cerebral palsy. Sixteen cases of this disorder have been documented but without histologic study. The histologic features of these two cases showed osteonecrosis with reparative changes. These findings support that this entity is similar to other osteochondroses of the quadriceps mechanism: Osgood-Schlatter disease and Sinding-Larsen-Johansson disease. PMID:12180619

The ''hot patella'' sign: is it of any clinical significance. Concise communication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fogelman, I.; McKillop, J.H.; Gray, H.W.

1983-04-01

The presence of the ''hot patella'' sign was evaluated in a prospective study of 200 consecutive bone scans, and in a review of scans from 148 patients with various metabolic bone disorders and 61 patients with lung carcinoma. The incidence was found to be 31%, 26% and 31% respectively. This sign is an extremely common scan finding and may be seen in association with a wide variety of disorders. It is concluded that this sign cannot be considered to be of diagnostic value.

Relationship between hamstring length and gluteus maximus strength with and without normalization.

PubMed

Lee, Dong-Kyu; Oh, Jae-Seop

2018-01-01

[Purpose] This study assessed the relationship between hamstring length and gluteus maximus (GM) strength with and without normalization by body weight and height. [Subjects and Methods] In total, 34 healthy male subjects volunteered for this study. To measure GM strength, subjects performed maximal hip joint extension with the knee joints flexed to 90° in the prone position. GM strength was normalized for body weight and height. [Results] GM strength with normalization was positively correlated with hamstring length, whereas GM strength without normalization was negatively correlated with hamstring length. [Conclusion] The normalization of GM strength by body weight and height has the potential to lead to more appropriate conclusions and interpretations about its correlation with hamstring length. Hamstring length may be related to GM strength.

Reconstruction of the extensor mechanism with fresh-frozen tendon allograft in total knee arthroplasty.

PubMed

Llombart Blanco, Rafael; Valentí, Andrés; Díaz de Rada, Pablo; Mora, Gonzalo; Valentí, Juan R

2014-11-01

Patellar tendon rupture after total knee replacement is a rare and highly limiting injury with multifactorial aetiology. Many reconstruction techniques have been described with not very predictable results. The use of allografts has been accepted as a suitable solution. A series of seven patients with patellar tendon rupture treated with fresh-frozen tendon allograft reconstruction after knee arthroplasty is presented. Median follow-up is 25 months (20-31). Functional assessment improved, and the knee society score and knee functional score improved from 26 and 16 to 82 and 55, respectively. Median extension lag was 5° (0°-20°), with a median range of motion of 95° (70-100). Radiological study showed a rise of the patella of 22.26 mm. The use of fresh-frozen allografts as a solution to patellar tendon ruptures after knee arthroplasty seems to provide acceptable results. Increased patellar height does not seem to affect functionality. Case series, Level IV.

Growth without growth hormone in combined pituitary hormone deficiency caused by pituitary stalk interruption syndrome

PubMed Central

Lee, Sang Soo; Han, A-Leum; Ahn, Moon Bae; Kim, Shin Hee; Cho, Kyoung Soon; Park, So Hyun; Jung, Min Ho; Suh, Byung-Kyu

2017-01-01

Growth hormone (GH) is an essential element for normal growth. However, reports of normal growth without GH have been made in patients who have undergone brain surgery for craniopharyngioma. Normal growth without GH can be explained by hyperinsulinemia, hyperprolactinemia, elevated leptin levels, and GH variants; however, its exact mechanism has not been elucidated yet. We diagnosed a female patient aged 13 with combined pituitary hormone deficiency (CPHD) caused by pituitary stalk interruption syndrome (PSIS). The patient has experienced recurrent hypoglycemic seizures since birth, but reached the height of 160 cm at the age of 13, showing normal growth. She grew another 8 cm for 3 years after the diagnosis, and she reached her final adult height of 168 cm which was greater than the midparental height, at the age of 16. The patient's blood GH and insulin-like growth factor-I levels were consistently subnormal, although her insulin levels were normal. Her physical examination conducted at the age of 15 showed truncal obesity, dyslipidemia, and osteoporosis, which are metabolic features of GH deficiency (GHD). Herein, we report a case in which a PSIS-induced CPHD patient attained her final height above mid parental height despite a severe GHD. PMID:28443260

Growth without growth hormone in combined pituitary hormone deficiency caused by pituitary stalk interruption syndrome.

PubMed

Lee, Sang Soo; Han, A-Leum; Ahn, Moon Bae; Kim, Shin Hee; Cho, Won Kyoung; Cho, Kyoung Soon; Park, So Hyun; Jung, Min Ho; Suh, Byung-Kyu

2017-03-01

Growth hormone (GH) is an essential element for normal growth. However, reports of normal growth without GH have been made in patients who have undergone brain surgery for craniopharyngioma. Normal growth without GH can be explained by hyperinsulinemia, hyperprolactinemia, elevated leptin levels, and GH variants; however, its exact mechanism has not been elucidated yet. We diagnosed a female patient aged 13 with combined pituitary hormone deficiency (CPHD) caused by pituitary stalk interruption syndrome (PSIS). The patient has experienced recurrent hypoglycemic seizures since birth, but reached the height of 160 cm at the age of 13, showing normal growth. She grew another 8 cm for 3 years after the diagnosis, and she reached her final adult height of 168 cm which was greater than the midparental height, at the age of 16. The patient's blood GH and insulin-like growth factor-I levels were consistently subnormal, although her insulin levels were normal. Her physical examination conducted at the age of 15 showed truncal obesity, dyslipidemia, and osteoporosis, which are metabolic features of GH deficiency (GHD). Herein, we report a case in which a PSIS-induced CPHD patient attained her final height above mid parental height despite a severe GHD.

On the Role of the Patella, ACL and Joint Contact Forces in the Extension of the Knee

PubMed Central

Cleather, Daniel J.; Southgate, Dominic F. L.; Bull, Anthony M. J.

2014-01-01

Traditional descriptions of the knee suggest that the function of the patella is to facilitate knee extension by increasing the moment arm of the quadriceps muscles. Through modelling and evidence from the literature it is shown in this paper that the presence of the patella makes the ability of the quadriceps to rotate the thigh greater than their ability to rotate the tibia. Furthermore, this difference increases as the knee is flexed, thus demonstrating a pattern that is consistent with many human movements. This paper also shows that the anterior cruciate ligament plays a previously unheralded role in extending the shank and that translation at the tibiofemoral and patellofemoral joints is important in improving the capacity for thigh rotation when the knee is flexed. This study provides new insights as to how the structure of the knee is adapted to its purpose and illustrates how the functional anatomy of the knee contributes to its extension function. PMID:25536067

Pubertal Height Velocity and Associations with Pre-pubertal and Adult Heights in Cystic Fibrosis

PubMed Central

Zhang, Zhumin; Lindstrom, Mary J.; Lai, HuiChuan J.

2013-01-01

Objectives To test the hypothesis that pubertal peak height velocity (PHV) in cystic fibrosis (CF) has improved and is influenced by pre-pubertal growth and genetic potential. Study design PHV from 1862 children born in 1984–87 and documented in the 1986–2008 US CF Foundation Registry was determined by statistical modeling and classified into normal, delayed (2-SD > average age), attenuated (magnitude < 5th percentile), or both (D&A). Genetic potential for height was estimated by parental stature. Results PHV averaged 8.4 cm/y at age 14.0 y in boys and 7.0 cm/y at age 12.1 y in girls, ~6 mo delay and ~15% reduction compared with healthy children. PHV was normal in 60%, delayed in 9%, attenuated in 21% and D&A in 5%. Patients with delayed PHV reached similar adult height percentile (boys: 34th, girls: 46th) to those with normal PHV (boys: 33rd, girls: 34th); both were significantly taller than the attenuated (boys: 11th, girls: 19th) and D&A PHV subgroups (boys: 8th, girls: 14th). Pancreatic sufficient patients had taller pre-pubertal and adult heights but similar PHV compared with pancreatic insufficient or meconium ileus patients. Adjusting for genetic potential reduced adult height percentiles more in boys (25th to 16th) than girls (28th to 24th). Height at age 7 y, PHV age and magnitude, and parental stature significantly predicted adult height. Conclusions Pubertal PHV has improved in children with CF born after mid 1980s compared with older cohorts but remains below normal. Suboptimal pre-pubertal and pubertal growth led to adult height below genetic potential in CF. PMID:23535012

Pseudo-Patella Baja after total knee arthroplasty

PubMed Central

Kazemi, Seyyed Morteza; Besheli, Laleh Daftari; Eajazi, Alireza; Sajadi, Mohammad Reza Miniator; Okhovatpoor, Mohammad Ali; Zanganeh, Ramin Farhang; Minaei, Reza

2011-01-01

Summary Background One of the complications of total knee arthroplasty (TKA) which has not yet been directly addressed is pseudo-patella baja (PPB). True patella baja (PB) is present when the length of the patellar tendon becomes shorter. PPB is present when the patella tendon is not shortened, but the level of the joint line is elevated. This study was conducted to assess PPB in TKA. Material/Methods Sixty patients who had had a primary TKA at our center between 1995 and 2005 were included. The average follow-up was 27.5 months. The Knee Society Scoring (KSS), lateral knee x-rays and the Blackburne-Peel index were used for assessments. Results Out of the 60 patients, 43 (72%) demonstrated no joint line elevation or patellar tendon shortening (group A). Fifteen patients (25%) had joint line elevation (group B), and both PB and PPB were present in 2 (3%) patients (group C). KSS was lower in groups B and C compared with group A, but this difference was not statistically significant. The average range of motion (ROM) in group A was significantly higher compared with either group B or C, and patients in groups B and C showed significantly more severe pain compared with group A (P<0.001). Conclusions PPB is not an uncommon finding after TKA and is associated with a statistically significant decrease in ROM and an increase in pain. Furthermore, KSS in the PPB group was less than in patients without PPB, although the difference was not statistically meaningful. PMID:21525812

Treatment of patella baja by a modified Z-plasty.

PubMed

Guido, Wierer; Christian, Hoser; Elmar, Herbst; Elisabeth, Abermann; Christian, Fink

2016-09-01

The purpose of this study was to evaluate the efficiency of a modified Z-plasty for patellar tendon lengthening for the treatment of patella baja. Rather than adapting only two tendon reins according to the conventional Z-plasty method, the modified Z-plasty provides four reins to enable multifold overlapping of the tendon tissue. Between 2010 and 2012, a modified Z-plasty procedure was performed in four patients suffering from patella baja. Physical examinations and standardized scoring instruments served as the evaluation measures. The median preoperative CD ratio of 0.53 (range 0.43-0.62) was corrected to 1.03 (range 1-1.06) after a median follow-up of 34 months (range 23-41 months). The median preoperative flexion of 108° (range 80-135°) improved to 143° (range 110-145°) compared with the flexion of 145° (range 140-145°) of the unaffected knee. No patients showed any signs of extension lag. The median Lysholm score improved from 49 (range 22-80) to 91 (range 67-95), and the Tegner activity level improved from 2 (range 0-6) to 6 (range 2-6). The median VAS status for pain decreased from an average of 8.5 (range 4-10) to 1 (range 0-2). No complications were observed. The modified Z-plasty procedure is a valuable technique for the treatment of patella baja, especially if allografts are not available. This procedure allowed for early mobilization and achieved excellent clinical results. IV.

The effect of infrapatellar fat pad resection on outcomes post-total knee arthroplasty: a systematic review.

PubMed

White, L; Holyoak, R; Sant, J; Hartnell, N; Mullan, J

2016-05-01

The infrapatellar fat pad (IPFP) is resected in approximately 88 % of total knee arthroplasty (TKA) surgeries. The aim of this review is to investigate the impact of the IPFP resection on clinical outcomes post-TKA. A systematic search of five major databases for all relevant articles published until May, 2015 was conducted. Studies comparing the effect of IPFP resection and preservation on outcomes post-TKA were included. Each study was then assessed individually for level of evidence and risk of bias. Studies were then grouped into post-operative outcomes and given a level of evidence ranking based on the collective strength of evidence. The systematic review identified ten studies suitable for inclusion, with a total of 10,163 patients. Within these ten studies, six post-operative outcomes were identified; knee pain, vascularisation of the patella, range of motion (ROM), patella tendon length/patella infera, wound complications and patient satisfaction. Moderate evidence increased knee pain with IPFP resection post-TKA was found. Conflicting evidence was found for patella vascularisation and patellar tendon length post-TKA. Moderate evidence for no difference in ROM was found. One low quality study was found for wound complications and patient satisfaction. This systematic review is limited by the lack of level one randomised controlled trials (RCTs). There is however moderate level evidence that IPFP resection increases post-operative knee pain. Further level one RCTs are required to produce evidence-based guidelines regarding IPFP resection. Systematic Review Level of Evidence: 3.

Comparison of Tension-Band Wiring With the Cable Pin System in Patella Fractures: A Randomized Prospective Study.

PubMed

Tian, Qing-xian; Hai, Yong; Du, Xin-ru; Xu, Zi-yu; Lu, Tie; Shan, Lei; Liu, Yang; Zhou, Jun-lin

2015-12-01

To compare the outcome of tension-band wiring (TBW) with the cable pin system (CPS) for transverse fractures of the patella. Randomized prospective study. Academic Level I trauma center. From February 2008 to December 2011, 73 consecutive patients with transverse fractures of the patella were prospectively enrolled in this study. The patients were randomly divided into 2 groups: one group was treated using the CPS, and the other group was treated using the modified TBW. The clinical outcome assessment included analyses of the radiographic images, the modified Hospital for Special Surgery scoring system, and complications. The follow-up time ranged from 12 to 29 months. All fractures healed, with a union rate of 100%. The fracture healing time was significantly shorter in the CPS group (8.51 ± 2.59 weeks, n = 34) compared with the TBW group (11.79 ± 3.04 weeks, n = 39). Postoperative complications in the CPS and TBW groups were observed in 1 and 9 patients, respectively, a difference that was statistically significant. The mean Hospital for Special Surgery score for the CPS group (90.53 ± 5.19 points) was significantly higher than that for the TBW group (81.36 ± 12.71 points). The CPS is a viable option for transverse fractures of the patella and is associated with a shorter healing time, fewer complications, and better function than TBW. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

The extent of man from Vitruvius to Marfan.

PubMed

Schott, G D

It is frequently stated that patients with Marfan's syndrome have an arm span greater than height. This implies a characteristic different from the proportions in normal adult man, in whom span and height are often thought to be equal. Such equality of span and height, which allows man to be portrayed within a square, has been a widely held concept, immortalised by Leonardo da Vinci, that dates from the Roman Vitruvius. However, in the past two hundred years, anthropometry has shown that span exceeds height in 59-78% of normal adult white men. Thus not only is the classic concept of equality of span and height generally incorrect, but also a span greater than height cannot be considered characteristic of Marfan's syndrome. Paradoxically, in some affected individuals, Vitruvian equality of height and span may occur.

Effect of growth hormone treatment on the adult height of children with chronic renal failure. German Study Group for Growth Hormone Treatment in Chronic Renal Failure.

PubMed

Haffner, D; Schaefer, F; Nissel, R; Wühl, E; Tönshoff, B; Mehls, O

2000-09-28

Growth hormone treatment stimulates growth in short children with chronic renal failure. However, the extent to which this therapy increases final adult height is not known. We followed 38 initially prepubertal children with chronic renal failure treated with growth hormone for a mean of 5.3 years until they reached their final adult height. The mean (+/-SD) age at the start of treatment was 10.4+/-2.2 years, the mean bone age was 7.1+/-2.3 years, and the mean height was 3.1+/-1.2 SD below normal. Fifty matched children with chronic renal failure who were not treated with growth hormone served as controls. The children treated with growth hormone had sustained catch-up growth, whereas the control children had progressive growth failure. The mean final height of the growth hormone-treated children was 165 cm for boys and 156 cm for girls. The mean final adult height of the growth hormone-treated children was 1.6+/-1.2 SD below normal, which was 1.4 SD above their standardized height at base line (P< 0.001). In contrast, the final height of the untreated children (2.1+/-1.2 SD below normal) was 0.6 SD below their standardized height at base line (P<0.001). Although prepubertal bone maturation was accelerated in growth hormone-treated children, treatment was not associated with a shortening of the pubertal growth spurt. The total height gain was positively associated with the initial target-height deficit and the duration of growth hormone therapy and was negatively associated with the percentage of the observation period spent receiving dialysis treatment. Long-term growth hormone treatment of children with chronic renal failure induces persistent catch-up growth, and the majority of patients achieve normal adult height.

Effect of the Earth's inner structure on the gravity in definitions of height systems

NASA Astrophysics Data System (ADS)

Tenzer, Robert; Foroughi, Ismael; Pitoňák, Martin; Šprlák, Michal

2017-04-01

In context of the vertical datum unification, the geoid-to-quasi-geoid separation has been of significant interest in recent years, because most of existing local vertical datums are realized in the system of either normal or orthometric heights. Nevertheless, the normal-orthometric heights are still used in many other countries where the normal gravity values along leveling lines were adopted instead of the observed gravity. Whereas the conversion between the orthometric and normal heights is defined by means of the mean gravity disturbances (i.e. differences between the mean values of the actual and normal gravity) along the plumbline within the topography, differences between the normal and normal-orthometric heights can be described by means of the surface gravity disturbances. Since the normal gravity field does not reflect the topographic masses and actual mass density distribution inside the Earth, the definition of gravity represents a principal aspect for a realization of particular vertical datum. To address this issue in this study, we investigate effects of the Earth's inner density structure on the surface and mean gravity disturbances, and discuss their impact on the vertical datum realization. These two gravity field quantities are computed globally with a spectral resolution complete to a spherical harmonic degree 2160 using the global gravity, terrain, ice-thickness, inland bathymetry and crustal structure models. Our results reveal that both, the surface and mean gravity disturbances mostly comprise the gravitational signal of topography and masses distributed below the geoid surface. Moreover, in polar areas, a significant contribution comes from large glaciers. In contrast, the contributions of anomalous density distribution within the topography attributed to major lakes, sediments and bedrock density variations are much less pronounced. We also demonstrate that the mean gravity disturbances within the topography are significantly modified compared to the corresponding surface values mainly due to topographic elevation and terrain geometry as well as the presence of large glaciers in polar regions. Changes of the vertical gravity gradient within the topography attributed to the masses distributed below the geoid (dominated mainly by the isostatic signature and the long-wavelength gravitational signature of deep mantle density heterogeneities) are, on the other hand, relatively small. Despite differences between the normal and normal-orthometric heights could directly be assessed from the surface gravity disturbances only when taken along leveling lines with information about the spirit leveling height differences, our results indicate that differences between these two height systems can be significant.

Cephalometric features in isolated growth hormone deficiency.

PubMed

Oliveira-Neto, Luiz Alves; Melo, Mariade de Fátima B; Franco, Alexandre A; Oliveira, Alaíde H A; Souza, Anita H O; Valença, Eugênia H O; Britto, Isabela M P A; Salvatori, Roberto; Aguiar-Oliveira, Manuel H

2011-07-01

To analyze cephalometric features in adults with isolated growth hormone (GH) deficiency (IGHD). Nine adult IGHD individuals (7 males and 2 females; mean age, 37.8 ± 13.8 years) underwent a cross-sectional cephalometric study, including 9 linear and 5 angular measurements. Posterior facial height/anterior facial height and lower-anterior facial height/anterior facial height ratios were calculated. To pool cephalometric measurements in both genders, results were normalized by standard deviation scores (SDS), using the population means from an atlas of the normal Brazilian population. All linear measurements were reduced in IGHD subjects. Total maxillary length was the most reduced parameter (-6.5 ± 1.7), followed by a cluster of six measurements: posterior cranial base length (-4.9 ± 1.1), total mandibular length (-4.4 ± 0.7), total posterior facial height (-4.4 ± 1.1), total anterior facial height (-4.3 ± 0.9), mandibular corpus length (-4.2 ± 0.8), and anterior cranial base length (-4.1 ± 1.7). Less affected measurements were lower-anterior facial height (-2.7 ± 0.7) and mandibular ramus height (-2.5 ± 1.5). SDS angular measurements were in the normal range, except for increased gonial angle (+2.5 ± 1.1). Posterior facial height/anterior facial height and lower-anterior facial height/anterior facial height ratios were not different from those of the reference group. Congenital, untreated IGHD causes reduction of all linear measurements of craniofacial growth, particularly total maxillary length. Angular measurements and facial height ratios are less affected, suggesting that lGHD causes proportional blunting of craniofacial growth.

The infrapatellar fat pad is a dynamic and mobile structure, which deforms during knee motion, and has proximal extensions which wrap around the patella.

PubMed

Stephen, Joanna M; Sopher, Ran; Tullie, Sebastian; Amis, Andrew A; Ball, Simon; Williams, Andy

2018-04-20

The infrapatellar fat pad (IFP) is a common cause of knee pain and loss of knee flexion and extension. However, its anatomy and behavior are not consistently defined. Thirty-six unpaired fresh frozen knees (median age 34 years, range 21-68) were dissected, and IFP attachments and volume measured. The rectus femoris was elevated, suprapatellar pouch opened and videos recorded looking inferiorly along the femoral shaft at the IFP as the knee was flexed. The patellar retinacula were incised and the patella reflected distally. The attachment of the ligamentum mucosum (LMuc) to the intercondylar notch was released from the anterior cruciate ligament (ACL), both menisci and to the tibia via meniscotibial ligaments. IFP strands projecting along both sides of the patella were elevated and the IFP dissected from the inferior patellar pole. Magnetic resonance imaging (MRI) of one knee at ten flexion angles was performed and the IFP, patella, tibia and femur segmented. In all specimens the IFP attached to the inferior patellar pole, femoral intercondylar notch (via the LMuc), proximal patellar tendon, intermeniscal ligament, both menisci and the anterior tibia via the meniscotibial ligaments. In 30 specimens the IFP attached to the anterior ACL fibers via the LMuc, and in 29 specimens it attached directly to the central anterior tibia. Proximal IFP extensions were identified alongside the patella in all specimens and visible on MRI [medially (100% of specimens), mean length 56.2 ± 8.9 mm, laterally (83%), mean length 23.9 ± 6.2 mm]. Mean IFP volume was 29.2 ± 6.1 ml. The LMuc, attached near the base of the middle IFP lobe, acting as a 'tether' drawing it superiorly during knee extension. The medial lobe consistently had a pedicle superomedially, positioned between the patella and medial trochlea. MRI scans demonstrated how the space between the anterior tibia and patellar tendon ('the anterior interval') narrowed during knee flexion, displacing the IFP superiorly and posteriorly as it conformed to the trochlear and intercondylar notch surfaces. Proximal IFP extensions are a novel description. The IFP is a dynamic structure, displacing significantly during knee motion, which is, therefore, vulnerable to interference from trauma or repetitive overload. Given that this trauma is often surgical, it may be appropriate that surgeons learn to minimize injury to the fat pad at surgery.

Sagittal plane tilting deformity of the patellofemoral joint: a new concept in patients with chondromalacia patella.

PubMed

Aksahin, Ertugrul; Aktekin, Cem Nuri; Kocadal, Onur; Duran, Semra; Gunay, Cüneyd; Kaya, Defne; Hapa, Onur; Pepe, Murad

2017-10-01

The aims of this study were to evaluate sagittal plane alignment in patients with chondromalacia patella via magnetic resonance imaging (MRI), analyse the relationships between the location of the patellar cartilaginous lesions and sagittal alignment and finally investigate the relationships between the sagittal plane malalignment and patellofemoral loadings using by finite element analysis. Fifty-one patients who were diagnosed with isolated modified Outerbridge grade 3-4 patellar chondromalacia based on MRI evaluation and 51 control subjects were evaluated. Chondromalacia patella patients were divided into three subgroups according to the chondral lesion location as superior, middle and inferior. The patella-patellar tendon angle (P-PT) was used for evaluation of sagittal alignment of patellofemoral joint. Each subgroup was compared with control group by using P-PT angle. To investigate the biomechanical effects of sagittal plane malpositioning on patellofemoral joint, bone models were created at 30°, 60° and 90° knee flexion by using mean P-PT angles, which obtained from patients with chondromalacia patellae and control subjects. The total loading and contact area values of the patellofemoral joints were investigated by finite element analysis. The mean age of all participants was 52.9 ± 8.2 years. The mean P-PT angle was significantly lower in chondromalacia group (142.1° ± 3.6°) compared to control group (144.5° ± 5.3°) (p = 0.008). Chondral lesions were located in superior, middle and inferior zones in 16, 20 and 15 patients, respectively. The mean P-PT angles in patients with superior (141.8 ± 2.7) and inferior subgroups (139.2 ± 2.3) were significantly lower than the values in the control group (p < 0.05). The contact area values were detected higher in models with chondromalacia than in the control models at the same flexion degrees. There were increased loadings at 30° and 90° flexions in the sagittal patellar tilt models. This study revealed that sagittal plain malpositioning of the patellofemoral joint might be related to chondromalacia, especially in the presence of lesions in the upper and lower part of the patella. This condition leads to supraphysiological loadings on the patellofemoral joint. Sagittal patellar tilt should be considered in the evaluation and management of patellar cartilage defects. Taking sagittal plane malalignment into consideration in patellofemoral joint evaluation will enable us to design new physical and surgical modalities. IV.

Lateral Patellofemoral Ligament: An Anatomic Study.

PubMed

Shah, Kalpit N; DeFroda, Steven F; Ware, James Kristopher; Koruprolu, Sarath C; Owens, Brett D

2017-12-01

Medial instability of the patellofemoral joint is a rare but known phenomenon that may result from an incompetent lateral patellofemoral ligament (LPFL). Surgical reconstruction of the LPFL has been described. However, anatomic details of the ligament have not been the subject of scrutiny. To describe the anatomic origin and insertion of the LPFL. Descriptive laboratory study. Ten fresh-frozen, unpaired human cadaveric knees (mean age, 57 years) were dissected to identify the LPFL. The dissection was carried out by elevating the iliotibial band to expose the deep capsular layer of the knee joint, followed by a medial parapatellar approach to the knee. Then the quadriceps and patellar tendons were sectioned, and the LPFL was isolated by visualization and palpation. The LPFL was dissected to reveal its origin and insertion; these were measured with respect to the lateral epicondyle and the superior-inferior axis of the lateral patella, respectively. On average, the LPFL had a variable point of origin in location as well as width about the lateral epicondyle. The LPFL originated, on average, 2.6 mm distal (range, 13.1 mm proximal to 11.4 mm distal) and 10.8 mm anterior (range, 7.3 mm posterior to 14.9 mm anterior) to the lateral epicondyle. The LPFL insertion on the patella was more reliably found to be about 45% (range, 23.7%-58.4%) of its lateral articular surface. The insertion on the patella was found to be in the middle third of the lateral patella. The LPFL has an origin that is variable but, on average, was found to be distal and anterior to the lateral epicondyle. The patella insertion was more reliably found to be in the middle third of the lateral patella. These anatomic relationships can help the surgeon reconstruct the LPFL in a more anatomic fashion. Surgeons who are tasked with reconstruction of the LPFL of a patient with idiopathic medial instability or a previous aggressive lateral release of the knee may reference this article to perform an anatomic reconstruction of the LPFL. We hope that having anatomic landmarks for the reconstruction of this ligament permits the surgeon to operate in an efficient manner that allows for the optimal outcome. This is a rare surgical issue, and no studies are available that provide this information. The little information present in the literature does not provide measurements for anatomic reconstruction; rather, it is limited to descriptions of reconstruction techniques that indirectly provide stability on the lateral aspect of the knee.

The use of copulas to practical estimation of multivariate stochastic differential equation mixed effects models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rupšys, P.

A system of stochastic differential equations (SDE) with mixed-effects parameters and multivariate normal copula density function were used to develop tree height model for Scots pine trees in Lithuania. A two-step maximum likelihood parameter estimation method is used and computational guidelines are given. After fitting the conditional probability density functions to outside bark diameter at breast height, and total tree height, a bivariate normal copula distribution model was constructed. Predictions from the mixed-effects parameters SDE tree height model calculated during this research were compared to the regression tree height equations. The results are implemented in the symbolic computational language MAPLE.

MULTIFUNCTION ENERGY PLATFORM (MFP) PILOT

EPA Science Inventory

• Multi-sector Baseline Survey:  A five-sector survey (agriculture, energy, water, health, and general - demogr...

• Metaphylogenomic and Potential Functionality of the Limpet Patella pellucida’s Gastrointestinal Tract Microbiome

  PubMed Central

  Dudek, Magda; Adams, Jessica; Swain, Martin; Hegarty, Matthew; Huws, Sharon; Gallagher, Joe

  2014-01-01

  This study investigated the microbial diversity associated with the digestive tract of the seaweed grazing marine limpet Patella pellucida. Using a modified indirect DNA extraction protocol and performing metagenomic profiling based on specific prokaryotic marker genes, the abundance of bacterial groups was identified from the analyzed metagenome. The members of three significantly abundant phyla of Proteobacteria, Firmicutes and Bacteroidetes were characterized through the literature and their predicted functions towards the host, as well as potential applications in the industrial environment assessed. PMID:25334059

• In vivo evaluation of biomechanical properties in the patellofemoral joint after matrix-associated autologous chondrocyte transplantation by means of quantitative T2 MRI.

  PubMed

  Pachowsky, M L; Trattnig, S; Wondrasch, B; Apprich, S; Marlovits, S; Mauerer, A; Welsch, Goetz H; Blanke, M

  2014-06-01

  To determine in vivo biomechanical properties of articular cartilage and cartilage repair tissue of the patella, using biochemical MRI by means of quantitative T2 mapping. Twenty MR scans were achieved at 3T MRI, using a new 8-channel multi-function coil allowing controlled bending of the knee. Multi-echo spin-echo T2 mapping was prepared in healthy volunteers and in age- and sex-matched patients after matrix-associated autologous chondrocyte transplantation (MACT) of the patella. MRI was performed at 0° and 45° of flexion of the knee after 0 min and after 1 h. A semi-automatic region-of-interest analysis was performed for the whole patella cartilage. To allow stratification with regard to the anatomical (collagen) structure, further subregional analysis was carried out (deep-middle-superficial cartilage layer). Statistical analysis of variance was performed. During 0° flexion (decompression), full-thickness T2 values showed no significant difference between volunteers (43 ms) and patients (41 ms). Stratification was more pronounced for healthy cartilage compared to cartilage repair tissue. During 45° flexion (compression), full-thickness T2 values within volunteers were significantly increased (54 ms) compared to patients (44 ms) (p < 0.001). Again, stratification was more pronounced in volunteers compared to patients. The volunteer group showed no significant increase in T2 values measured in straight position and in bended position. There was no significant difference between the 0- and the 60-min MRI examination. T2 values in the patient group increased between the 0- and the 60-min examination. However, the increase was only significant in the superior cartilage layer of the straight position (p = 0.021). During compression (at 45° flexion), healthy patellar cartilage showed a significant increase in T2-values, indicating adaptations of water content and collagen fibril orientation to mechanical load. This could not be observed within the patella cartilage after cartilage repair (MACT) of the patella, most obvious due to a lack of biomechanical adjustment. III.

• Evaluation of chondromalacia of the patella with axial inversion recovery-fast spin-echo imaging.

  PubMed

  Lee, S H; Suh, J S; Cho, J; Kim, S J; Kim, S J

  2001-03-01

  The purpose of our study was to assess the accuracy of inversion recovery-fast spin-echo (IR-FSE) imaging for the evaluation of chondromalacia of the patella. Eighty-six patients were included, they underwent magnetic resonance (MR) examination and subsequent knee arthroscopy. Medial and lateral facets of the patella were evaluated separately. Axial images were obtained by using IR-FSE (TR/TE/TI = 3000/25/150 msec; echo train length, 8; 4-mm thickness; 12-cm field of view; 512 x 256 matrix; two, number of excitations) with a 1.5-T MR machine. MR interpretation of chondromalacia was made on the basis of the arthroscopic grading system. Of a total of 172 facets graded, arthroscopy revealed chondromalacia in 14 facets with various grades (G0, 158; G1, 1; G2, 3; G3, 6; G4, 4). Sensitivity, specificity, and accuracy in the chondromalacia grades were 57.1%, 93.0%, and 90.1%, respectively. There was one false-negative case (G4) and 11 false-positive cases (G1, eight; G2, two; G3, one). Sensitivity and specificity corrected by one grade difference were improved to 85.7% and 98.1%, respectively. When cartilage changes were grouped into early (corresponding to grade 1 and 2) and advanced (grade 3 and 4) diseases, sensitivity and specificity of the early and advanced diseases were 75% and 94% and 80% and 99%, respectively. IR-FSE imaging of the knee revealed high specificity but low sensitivity for the evaluation of chondromalacia of the patella.

• [A finite element analysis of petal-shaped poly-axial locking plate fixation in treatment of Y-shaped patellar fracture].

  PubMed

  Meng, Depeng; Ouyang, Yueping; Hou, Chunlin

  2017-12-01

  To establish the finite element model of Y-shaped patellar fracture fixed with titanium-alloy petal-shaped poly-axial locking plate and to implement the finite element mechanical analysis. The three-dimensional model was created by software Mimics 19.0, Rhino 5.0, and 3-Matic 11.0. The finite element analysis was implemented by ANSYS Workbench 16.0 to calculate the Von-Mises stress and displacement. Before calculated, the upper and lower poles of the patella were constrained. The 2.0, 3.5, and 4.4 MPa compressive stresses were applied to the 1/3 patellofemoral joint surface of the lower, middle, and upper part of the patella respectively, and to simulated the force upon patella when knee flexion of 20, 45, and 90°. The number of nodes and elements of the finite element model obtained was 456 839 and 245 449, respectively. The max value of Von-Mises stress of all the three conditions simulated was 151.48 MPa under condition simulating the knee flexion of 90°, which was lower than the yield strength value of the titanium-alloy and patella. The max total displacement value was 0.092 8 mm under condition simulating knee flexion of 45°, which was acceptable according to clinical criterion. The stress concentrated around the non-vertical fracture line and near the area where the screws were sparse. The titanium-alloy petal-shaped poly-axial locking plate have enough biomechanical stiffness to fix the Y-shaped patellar fracture, but the result need to be proved in future.

• Articulation of Native Cartilage Against Different Femoral Component Materials. Oxidized Zirconium Damages Cartilage Less Than Cobalt-Chrome.

  PubMed

  Vanlommel, Jan; De Corte, Ronny; Luyckx, Jean Philippe; Anderson, Melissa; Labey, Luc; Bellemans, Johan

  2017-01-01

  Oxidized zirconium (OxZr) is produced by thermally driven oxidization creating an oxidized surface with the properties of a ceramic at the top of the Zr metal substrate. OxZr is much harder and has a lower coefficient of friction than cobalt-chrome (CoCr), both leading to better wear characteristics. We evaluated and compared damage to the cartilage of porcine patella plugs, articulating against OxZr vs CoCr. Our hypothesis was that, owing to its better wear properties, OxZr would damage cartilage less than CoCr. If this is true, OxZr might be a better material for the femoral component during total knee arthroplasty if the patella is not resurfaced. Twenty-one plugs from porcine patellae were prepared and tested in a reciprocating pin-on-disk machine while lubricated with bovine serum and under a constant load. Three different configurations were tested: cartilage-cartilage as the control group, cartilage-OxZr, and cartilage-CoCr. Macroscopic appearance, cartilage thickness, and the modified Mankin score were evaluated after 400,000 wear cycles. The control group showed statistically significant less damage than plugs articulating against both other materials. Cartilage plugs articulating against OxZr were statistically significantly less damaged than those articulating against CoCr. Although replacing cartilage by an implant always leads to deterioration of the cartilage counterface, OxZr results in less damage than CoCr. The use of OxZr might thus be preferable to CoCr in case of total knee arthroplasty without patella resurfacing. Copyright © 2016 Elsevier Inc. All rights reserved.

• Linkage analysis of the Nail-patella syndrome

  DOE Office of Scientific and Technical Information (OSTI.GOV)

  Campeau, E.; Watkins, D.; Rouleau, G.A.

  1995-01-01

  Nail-patella syndrome (NPS) is an autosomal dominant disorder characterized by dysplasia of nails and patella, decreased mobility of the elbow, iliac horns, and, in some cases, nephropathy. The disorder has been mapped to the long arm of chromosome 9, but the precise localization and identity of the NPS gene are unknown. Linkage analysis in three NPS families, using highly informative dinucleotide repeat polymorphisms on 9q33-q34, confirmed linkage of NPS to this chromosome. Recombinations were detected, by two-point linkage analysis, between NPS and the centromeric markers D9S60 and the gelsolin gene and the telomeric markers D9S64 and D9S66, in one ofmore » the families. Haplotype analysis suggested an additional recombination between NPS and the argininosuccinate synthetase (ASS) gene. These results localize the NPS gene to an interval on 9q34.1, distal to D9S60 an proximal to ASS, comprising a genetic distance of {approximately}9 cM. This represents a significant refinement in the localization of the NPS gene. 25 refs., 2 figs., 1 tab.« less

• Nociceptive role of substance-P in the knee joint of a patient with congenital insensitivity to pain.

  PubMed

  Derwin, K A; Glover, R A; Wojtys, E M

  1994-01-01

  This case report describes the immunocytochemical examination of tissue from a 9-year-old black child diagnosed with congenital insensitivity to pain at age 5. A recent fall and resulting patella fracture required surgical treatment. Biopsies of the distal pole and surrounding soft tissue, as well as a sample of his patellofemoral joint fluid, were taken at the time of partial patellectomy and analyzed for substance-P (SP). Morphologic staining of the patella showed a grossly degenerated patellofemoral articular surface. Examination of tissue sections stained either immunocytochemically with diaminobenzidine DAB or by a rhodamine fluorescent labeling technique showed no evidence of SP-positive nerve fibers. Furthermore, only a trace amount of SP (7.29 pg/ml) was detected in a sample of the patient's knee joint synovial fluid. This patient's absence of pain sensation in conjunction with the absence of SP nerve fibers in stained patella sections and identification of only trace levels of SP in his synovial fluid, further implicates this neuropeptide in nociceptive innervation of diarthrodial joints.

• Effect on adult height of pubertal growth hormone retesting and withdrawal of therapy in patients with previously diagnosed growth hormone deficiency.

  PubMed

  Zucchini, Stefano; Pirazzoli, Piero; Baronio, Federico; Gennari, Monia; Bal, Milva Orquidea; Balsamo, Antonio; Gualandi, Stefano; Cicognani, Alessandro

  2006-11-01

  GH replacement therapy in GH-deficient (GHD) patients is usually continued until adult height despite the fact that most of these subjects display a normal secretion when retested at the end of growth. Puberty is the most likely time for normalization of GH secretion. The objectives of this study are to establish the characteristics and the percentage of the subjects with isolated GHD who normalized secretion at puberty and to compare their statural outcomes with those of the subjects with persistent deficiency treated also after retesting. This was a prospective, nonrandomized, open-label study conducted in a university research hospital. Sixty-nine subjects (40 male, 29 female) with a diagnosis before puberty of isolated GHD by means of arginine and l-dopa tests were reevaluated with the same tests after at least 2 yr of therapy and after puberty onset. If GH peak at retesting was more than 10 microg/liter, therapy was withdrawn. Percentage and characteristics of normalized subjects at retesting, outcome of treatment in the subjects treated or untreated to adult height, and factors predictive of growth outcome were measured. At retesting, 44 subjects (63.7%) confirmed a GH peak less than 10 microg/liter (24 of 40 male and 20 of 29 female). Apart from a less delayed bone age at diagnosis in females, the subjects with confirmed GHD were not different at diagnosis from the other group for height deficit at diagnosis, first year growth response to GH, age and height at puberty onset, height, and IGF-I at retesting. Mean adult height was 165.1 +/- 4.5 cm in the male group treated until adult height vs. 164.0 +/- 3.4 cm in the group who suspended therapy at retesting. Mean adult height was 153.2 +/- 4.1 cm in the female group treated until adult height vs. 152.9 +/- 5.2 cm in the group that suspended therapy at retesting. As regards the parameters expressing the final outcome, the only difference was found in the mean increment adult height-target height sd score in favor of the male group treated until adult height. In both sexes, therapy duration and GH levels at diagnosis and at retesting were unrelated to adult height parameters and to height increments during the period of observation. One third of our GHD subjects diagnosed before puberty presented a normal secretion at puberty. The withdrawal of GH therapy in these subjects after retesting was not associated with a catch down growth, and they obtained an adult height similar to those obtained by the GHD subjects treated until adult height. It seems convenient, in subjects with nonsevere GHD, to retest GH secretion at midpuberty and to withdraw treatment for the subjects that are no longer deficient.

• TOPEX/El Nino Watch - Satellite shows El Nino-related Sea Surface Height, Mar, 14, 1998

  NASA Technical Reports Server (NTRS)

  1998-01-01

  This image of the Pacific Ocean was produced using sea surface height measurements taken by the U.S.-French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on Mar. 14, 1998 and sea surface height is an indicator of the heat content of the ocean. The image shows that the sea surface height along the central equatorial Pacific has returned to a near normal state. Oceanographers indicate this is a classic pattern, typical of a mature El Nino condition. Remnants of the El Nino warm water pool, shown in red and white, are situated to the north and south of the equator. These sea surface height measurements have provided scientists with a detailed view of how the 1997-98 El Nino's warm pool behaves because the TOPEX/Poseidon satellite measures the changing sea surface height with unprecedented precision. In this image, the white and red areas indicate unusual patterns of heat storage; in the white areas, the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal; in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions, while purple (the western Pacific) means at least 18 centimeters (7 inches) below normal sea level. The El Nino phenomenon is thought to be triggered when the steady westward blowing trade winds weaken and even reverse direction. This change in the winds allows a large mass of warm water (the red and white area) that is normally located near Australia to move eastward along the equator until it reaches the coast of South America. The displacement of so much warm water affects evaporation, where rain clouds form and, consequently, alters the typical atmospheric jet stream patterns around the world. Using satellite imagery, buoy and ship data, and a forecasting model of the ocean-atmosphere system, the National Oceanic and Atmospheric Administration, (NOAA), has continued to issue an advisory indicating the so-called El Nino weather conditions that have impacted much of the United States and the world are expected to remain through the spring.

• Growth hormone secretory pattern and response to treatment in children with short stature followed to adult height.

  PubMed

  Radetti, Giorgio; Buzi, Fabio; Cassar, Walburga; Paganini, Claudio; Stacul, Elisabetta; Maghnie, Mohamad

  2003-07-01

  To compare the relative utility of GH stimulation tests and assays of spontaneous GH secretion as predictors of change in height standard deviation score at the end of GH treatment in children with short stature. We retrospectively studied 116 children (67 boys and 49 girls) with subnormal growth rates and short stature, defined as a height of more than 2SD below the mean for age and sex. The patients were classified according to their pattern of findings on baseline pharmacological GH stimulation tests and a 12-h assay of nocturnal spontaneous GH secretion. Twenty-eight patients (24%) had normal hormone levels by both methods (group I); 14 (12%) had normal levels by stimulation tests but subnormal levels by the physiological assay (group II); 48 (41%) had subnormal levels on pharmacological stimulation, with normal physiologic levels (group III); and 26 (22%) had subnormal levels by both methods (group IV). All children in groups II and IV, and 27 in group III, designated IIIb, were treated with recombinant GH at 0.7 U (0.23 mg/kg) of body weight per week. GH secretory patterns were related to final height SD scores and other growth parameters, after the patients had attained their adult stature 6.7 +/- 2.2 years (SD) after GH evaluation. The five groups were similar with respect to mean baseline height SD scores for chronological as well as bone age. Whether assessed as absolute or parentally adjusted (relative) values, mean gains in height SD scores were significantly greater in treated patients with physiological hormone deficiency (groups II and IV) than in those with normal hormone levels (group I, untreated controls). Relative height gains were 1.03 +/- 1.45 cm (6.6 +/- 9.28 cm) and 1.85 +/- 1.21 cm (SDS; 11.8 +/- 7.74 cm) in groups II and IV respectively, compared with only 0.11 +/- 0.42 cm (0.7 +/- 2.68 cm) in group I (P < 0.01 and P < 0.001). GH treatment failed to improve either the absolute or parentally adjusted final height of patients with GH deficiency by stimulation tests but normal levels by physiological assay. Long-term administration of GH to short children with normal spontaneous GH secretion is not associated with an appreciable increase in adult height.

• CLOSING THE BIODIESEL LOOP: SELF SUSTAINING COMMUNITY BASED BIODIESEL PRODUCTION

  EPA Science Inventory

  Biofuels Technology TEC 4700/5700          Contribution of human growth hormone-releasing hormone receptor (GHRHR) gene sequence variation to isolated severe growth hormone deficiency (ISGHD) and normal adult height.

  PubMed

  Camats, Núria; Fernández-Cancio, Mónica; Carrascosa, Antonio; Andaluz, Pilar; Albisu, M Ángeles; Clemente, María; Gussinyé, Miquel; Yeste, Diego; Audí, Laura

  2012-10-01

  Molecular causes of isolated severe growth hormone deficiency (ISGHD) in several genes have been established. The aim of this study was to analyse the contribution of growth hormone-releasing hormone receptor (GHRHR) gene sequence variation to GH deficiency in a series of prepubertal ISGHD patients and to normal adult height. A systematic GHRHR gene sequence analysis was performed in 69 ISGHD patients and 60 normal adult height controls (NAHC). Four GHRHR single-nucleotide polymorphisms (SNPs) were genotyped in 248 additional NAHC. An analysis was performed on individual SNPs and combined genotype associations with diagnosis in ISGHD patients and with height-SDS in NAHC. Twenty-one SNPs were found. P3, P13, P15 and P20 had not been previously described. Patients and controls shared 12 SNPs (P1, P2, P4-P11, P16 and P21). Significantly different frequencies of the heterozygous genotype and alternate allele were detected in P9 (exon 4, rs4988498) and P12 (intron 6, rs35609199); P9 heterozygous genotype frequencies were similar in patients and the shortest control group (heights between -2 and -1 SDS) and significantly different in controls (heights between -1 and +2 SDS). GHRHR P9 together with 4 GH1 SNP genotypes contributed to 6·2% of height-SDS variation in the entire 308 NAHC. This study established the GHRHR gene sequence variation map in ISGHD patients and NAHC. No evidence of GHRHR mutation contribution to ISGHD was found in this population, although P9 and P12 SNP frequencies were significantly different between ISGHD and NAHC. Thus, the gene sequence may contribute to normal adult height, as demonstrated in NAHC. © 2012 Blackwell Publishing Ltd.

• Constitutional growth delay pattern of growth in velo-cardio-facial syndrome: longitudinal follow up and final height of two cases.

  PubMed

  Turan, Serap; Ozdemir, Nihal; Güran, Tülay; Akalın, Figen; Akçay, Teoman; Ayabakan, Canan; Yılmaz, Yüksel; Bereket, Abdullah

  2008-01-01

  We report two patients with velo-cardio-facial syndrome (VCFS) who were admitted to our pediatric endocrinology clinic because of short stature and followed longitudinally until attainment of final height. Both patients followed a growth pattern consistent with constitutional delay of puberty with normal and near normal final height. Case 2 also had partial growth hormone (GH) deficiency and severe short stature (height SDS -3.4 SDS), but showed spontaneous catch-up and ended up with a final height of -2 SDS. These cases suggest that short stature in children with VCFS is due to a pattern of growth similar to that observed in constitutional delay of growth and puberty.

• Mathematical simulations of photon interactions using Monte Carlo analysis to evaluate the uncertainty associated with in vivo K X-ray fluorescence measurements of stable lead in bone

  NASA Astrophysics Data System (ADS)

  Lodwick, Camille J.

  This research utilized Monte Carlo N-Particle version 4C (MCNP4C) to simulate K X-ray fluorescent (K XRF) measurements of stable lead in bone. Simulations were performed to investigate the effects that overlying tissue thickness, bone-calcium content, and shape of the calibration standard have on detector response in XRF measurements at the human tibia. Additional simulations of a knee phantom considered uncertainty associated with rotation about the patella during XRF measurements. Simulations tallied the distribution of energy deposited in a high-purity germanium detector originating from collimated 88 keV 109Cd photons in backscatter geometry. Benchmark measurements were performed on simple and anthropometric XRF calibration phantoms of the human leg and knee developed at the University of Cincinnati with materials proven to exhibit radiological characteristics equivalent to human tissue and bone. Initial benchmark comparisons revealed that MCNP4C limits coherent scatter of photons to six inverse angstroms of momentum transfer and a Modified MCNP4C was developed to circumvent the limitation. Subsequent benchmark measurements demonstrated that Modified MCNP4C adequately models photon interactions associated with in vivo K XRF of lead in bone. Further simulations of a simple leg geometry possessing tissue thicknesses from 0 to 10 mm revealed increasing overlying tissue thickness from 5 to 10 mm reduced predicted lead concentrations an average 1.15% per 1 mm increase in tissue thickness (p < 0.0001). An anthropometric leg phantom was mathematically defined in MCNP to more accurately reflect the human form. A simulated one percent increase in calcium content (by mass) of the anthropometric leg phantom's cortical bone demonstrated to significantly reduce the K XRF normalized ratio by 4.5% (p < 0.0001). Comparison of the simple and anthropometric calibration phantoms also suggested that cylindrical calibration standards can underestimate lead content of a human leg up to 4%. The patellar bone structure in which the fluorescent photons originate was found to vary dramatically with measurement angle. The relative contribution of lead signal from the patella declined from 65% to 27% when rotated 30°. However, rotation of the source-detector about the patella from 0 to 45° demonstrated no significant effect on the net K XRF response at the knee.

• Transplantation of free tibial periosteal grafts for the repair of articular cartilage defect: An experimental study

  PubMed Central

  Singh, Ravijot; Chauhan, Vijendra; Chauhan, Neena; Sharma, Sansar

  2009-01-01

  Background: Articular chondrocytes have got a long lifespan but rarely divides after maturity. Thus, an articular cartilage has a limited capacity for repair. Periosteal grafts have chondrogenic potential and have been used to repair defects in the articular cartilage. The purpose of the present study is to investigate the differentiation of free periosteal grafts in the patellofemoral joint where the cambium layer faces the subchondral bone and to investigate the applicability of periosteal grafts in the reconstruction of articular surfaces. Materials and Methods: The study was carried out over a period of 1 year on 25 adult, male Indian rabbits after obtaining permission from the institutional animal ethical committee. A full-thickness osteochondral defect was created by shaving off the whole articular cartilage of the patella of the left knee. The defect thus created was grafted with free periosteal graft. The patella of the right knee was taken as a control where no grafting was done after shaving off the articular cartilage. The first animal was used to study the normal histology of the patellar articular cartilage and periosteum obtained from the medial surface of tibial condyle. Rest 24 animals were subjected to patellectomy, 4 each at serial intervals of 2, 4, 8, 16, 32 and 48 weeks and the patellar articular surfaces were examined macroscopically and histologically. Results: The grafts got adherent to the underlying patellar articular surface at the end of 4 weeks. Microscopically, graft incorporation could be appreciated at 4 weeks. Mesenchymal cells of the cambium layer were seen differentiating into chondrocytes by the end of 4 weeks in four grafts (100%) and they were arranged in a haphazard manner. Till the end of 8 weeks, the cellular arrangement was mostly wooly. At 16 weeks, one graft (25%) had wooly arrangement of chondrocytes and three grafts (75%) had columnar formation of cells. Same percentage was maintained at 32 weeks. Four grafts (100%) at 48 weeks showed columnar orientation. The control side showed no changes over the shaved off articular surface in all the rabbits. One rabbit at 4 weeks had a dislocation of the patella on the control side. None of the rabbits developed any infection or wound dehiscence. Conclusion: Autologous periosteal graft transplantation can be a promising substitute for articular cartilaginous defects. PMID:19838382

• Magnetic resonance evaluation of the knee in children and adolescents with achondroplasia.

  PubMed

  Akyol, Yakup; Averill, Lauren W; Atanda, Alfred; Kecskemethy, Heidi H; Bober, Michael B; Mackenzie, William G

  2015-06-01

  Achondroplasia is the most common form of skeletal dysplasia. Although the radiographic features are well described, MRI features of the knee in achondroplasia have not been reported. To describe common MRI characteristics of the knee joint in symptomatic children and adolescents with achondroplasia. We retrospectively evaluated 10 knee MRI examinations in 8 children and young adults (age range 11-20 years, mean 16.3 years) with achondroplasia. We measured modified Insall-Salvati index, knee flexion angle, anterior cruciate ligament (ACL)-Blumensaat line angle, ACL-tibial angle, posterior cruciate ligament (PCL) angle, intercondylar notch width index, and intercondylar notch depth index. We compared our findings with an age- and gender-matched control group of 20 children (age range 15-18 years; mean 16 years) with normal knee MRIs. All 10 knees in the achondroplasia group had discoid lateral meniscus; 8 meniscal tears were identified. Patella baja was present in half of the study cases. Greater knee flexion and increased ACL-Blumensaat line and PCL angles were seen in all achondroplasia knees. ACL-tibial angle was similar in the study and in the control group. Children with achondroplasia had deeper A-shape femoral notches that extended more anteriorly than those seen in the control group. MRI findings were confirmed in all seven knees with arthroscopic correlation. Discoid lateral meniscus, often with tear, is a consistent feature in knee MRIs of symptomatic children and adolescents with achondroplasia. Other findings include patella baja, knee flexion, deep A-shape intercondylar notch, increased ACL-Blumensaat line angle and taut PCL.

• Computation of distribution of minimum resolution for log-normal distribution of chromatographic peak heights.

  PubMed

  Davis, Joe M

  2011-10-28

  General equations are derived for the distribution of minimum resolution between two chromatographic peaks, when peak heights in a multi-component chromatogram follow a continuous statistical distribution. The derivation draws on published theory by relating the area under the distribution of minimum resolution to the area under the distribution of the ratio of peak heights, which in turn is derived from the peak-height distribution. Two procedures are proposed for the equations' numerical solution. The procedures are applied to the log-normal distribution, which recently was reported to describe the distribution of component concentrations in three complex natural mixtures. For published statistical parameters of these mixtures, the distribution of minimum resolution is similar to that for the commonly assumed exponential distribution of peak heights used in statistical-overlap theory. However, these two distributions of minimum resolution can differ markedly, depending on the scale parameter of the log-normal distribution. Theory for the computation of the distribution of minimum resolution is extended to other cases of interest. With the log-normal distribution of peak heights as an example, the distribution of minimum resolution is computed when small peaks are lost due to noise or detection limits, and when the height of at least one peak is less than an upper limit. The distribution of minimum resolution shifts slightly to lower resolution values in the first case and to markedly larger resolution values in the second one. The theory and numerical procedure are confirmed by Monte Carlo simulation. Copyright © 2011 Elsevier B.V. All rights reserved.

• Effects of static stretching of knee musculature on patellar alignment and knee functional disability in male patients diagnosed with knee extension syndrome: A single-group, pretest-posttest trial.

  PubMed

  Pourahmadi, Mohammad Reza; Ebrahimi Takamjani, Ismail; Hesampour, Kazem; Shah-Hosseini, Gholam Reza; Jamshidi, Ali Ashraf; Shamsi, Mohammad Bagher

  2016-04-01

  Knee extension (Kext) syndrome is based on movement system impairments and is described as knee pain associated with quadriceps stiffness. To investigate the effects of 3 times per week for 4 weeks static stretching of knee musculature on patellar alignment and knee functional disability in male Kext syndrome patients. A single-group, pretest-posttest clinical trial. Hazrat-e-Rasoul Akram Hospital. Forty-six male Kext syndrome patients aged 18-35 years. Knee functional disability was assessed by the Kujala questionnaire. Patellar tilt was assessed using the skyline view X-ray. In addition, patella alta was assessed by X-ray using the Insall-Salvati ratio. After intervention, changes in knee flexion-extension range of motion (ROM) and hip adduction were assessed by goniometer and inclinometer. Changes in patellar tilt and patella alta were evaluated. Correlations between muscles length, patellar tilt and knee functional disability were also evaluated. The mean of patellar tilt in male Kext syndrome patients was 15.19°. Only the correlation between rectus femoris shortness and patellar tilt (P = 0.002) and the correlation between rectus femoris shortness and knee functional disability (P = 0.037) were significant. Patella alta was not severe in male Kext syndrome patients (1.28 ± 0.10). Knee flexion-extension ROM and femoral adduction increased significantly after a 12-session stretching programme (P < 0.0001). The results demonstrated that rectus femoris shortness had higher correlation with patellar tilt and knee functional disability than iliotibial band and hamstring shortness. Stretching was effective in reducing patellar tilt, patella alta, knee functional disability, increasing knee ROM and hip adduction in these patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

• Associations of cumulative Pb exposure and longitudinal changes in Mini-Mental Status Exam scores, global cognition and domains of cognition: The VA Normative Aging Study.

  PubMed

  Farooqui, Zishaan; Bakulski, Kelly M; Power, Melinda C; Weisskopf, Marc G; Sparrow, David; Spiro, Avron; Vokonas, Pantel S; Nie, Linda H; Hu, Howard; Park, Sung Kyun

  2017-01-01

  Lead (Pb) exposure has been associated with poorer cognitive function cross-sectionally in aging adults, however the association between cumulative Pb exposure and longitudinal changes in cognition is little characterized. In a 1993-2007 subcohort of the VA Normative Aging Study (Mini-mental status exam (MMSE) n=741; global cognition summary score n=715), we used linear mixed effects models to test associations between cumulative Pb exposure (patella or tibia bone Pb) and repeated measures of cognition (MMSE, individual cognitive tests, and global cognition summary). Cox proportional hazard modeling assessed the risk of an MMSE score falling below 25. Among men 51-98 at baseline, higher patella Pb concentration (IQR: 21μg/g) was associated with -0.13 lower baseline MMSE (95% CI: -0.25, -0.004) and faster longitudinal MMSE decline (-0.016 units/year, 95% CI: -0.032, -0.0004) over 15 years. Each IQR increase in patella Pb was associated with increased risk of a MMSE score below 25 (HR=1.21, 95% CI: 0.99, 1.49; p=0.07). There were no significant associations between Pb and global cognition (both baseline and longitudinal change). Patella Pb was associated with faster longitudinal decline in Word List Total Recall in the language domain (0.014 units/year, 95% CI: -0.026, -0.001) and Word List Delayed Recall in the memory domain (0.014 units/year, 95% CI: -0.027, -0.002). We found weaker associations with tibia Pb. Cumulative Pb exposure is associated with faster declines in MMSE and Word List Total and Delayed Recall tests. These findings support the hypothesis that Pb exposure accelerates cognitive aging. Copyright © 2016 Elsevier Inc. All rights reserved.