Lateral Patellofemoral Joint Research Articles

Mechanical characterization of the ligaments in subject-specific models of the patellofemoral joint using in vivo laxity tests

BackgroundThe purpose of this study was to propose a methodology for mechanical characterization of the ligaments in subject-specific models of the patellofemoral joint (PFJ) of living individuals. MethodPFJ laxity tests were performed on a healthy volunteer using a specially designed loading apparatus under biplane fluoroscopy. A three-dimensional (3D) parametric model of the PFJ was developed in the framework of the rigid body spring model using the geometrical data acquired from the subject's computed tomography and magnetic resonance images. The stiffness and pre-strains of the medial and lateral PFJ ligaments were characterized using a two-step optimization procedure which minimized the deviation between the model predictions and the calibration test results. Sensitivity analyses were performed to investigate the effect of mechanical properties of the non-characterized model components on the characterization procedure and its results. ResultsThe overall findings indicate that the proposed methodology is applicable and can improve the model predictions effectively. For the subject under study, ligament characterization reduced the root mean square of the deviations between the patellar shift and tilt predicted by the model and obtained experimentally for the validation laxity test (from 6.2 mm to 0.5 mm, and from 8.4° to 1.5°, respectively) and passive knee flexion test (from 1.4 mm to 0.3 mm, and from 2.3° to 1.3°, respectively). The non-characterized mechanical properties were found to have a minimal effect on the characterization procedure and its results. ConclusionThe proposed methodology can help in developing truly patient-specific models of the PFJ, to be used for personalized preplanning of the clinical interventions.

Research progress about influence of patellofemoral osteoarthritis on effectiveness of unicompartmental knee arthroplasty

To summarize the current research progress about influence of patellofemoral osteoarthritis on clinical outcome of unicompartmental knee arthroplasty (UKA). The recent related literature was extensively reviewed and summarized, including pros and cons to regard the patellofemoral osteoarthritis as the contraindication. Previous studies regarded patellofemoral osteoarthritis as the contraindication of UKA. Most of current researches show that the damage to the articular cartilage of the patellofemoral joint to the extent of full-thickness cartilage loss has no influence on outcome of UKA. There is no correlation between preoperative anterior knee pain or medial patellofemoral joint degeneration and the clinical outcome. However, lateral subluxation of the patella has an adverse impact on postoperative curative effect. Degeneration of the lateral patellofemoral joint may be a risk factor of the outcome. Patellofemoral osteoarthritis should not be the absolute contraindication of UKA. The effect of degeneration of the lateral patellofemoral joint is not clear at present, and still needs further studies in the future.

Arthroscopic treatment of symptomatic lateral synovial plica of the knee.

Synovial plicae are often observed when performing arthroscopic surgery, but their pathological nature and the necessity for treatment are still controversial. There are few reports regarding lateral synovial plicae because it is considered extremely rare. The purpose of this study was to report the clinical outcomes of athletes with symptomatic lateral synovial plicae who underwent arthroscopic surgery. Ten patients with lateral synovial plica underwent arthroscopic surgery. Of the 10 patients, 5 were male and 5 were female, and their average age was 19.1 years. The chief symptoms were anterolateral knee pain, limited range of motion due to pain, and catching. All patients failed nonoperative management. The average period between the onset of lateral synovial plica syndrome and the knee surgery was 5.6 months. The average follow-up period after surgery was 8.4 months. The arthroscopic findings revealed that a plica-like structure existed in the lateral patellofemoral joint. After surgery, pain and limited range of joint motion were improved in all cases and catching and locking disappeared. No complications were observed; however, the pain relapsed after surgery in one patient who had slow onset. In this patient, another resection of the synovial plica provided symptomatic improvement. Arthroscopic resection of symptomatic lateral synovial plicae was performed with good results. Lateral synovial plica syndrome is a rare condition. However, when treating athletes with anterolateral knee pain, lateral synovial plicae should be considered.

Kinematically aligned total knee arthroplasty reproduces native patellofemoral biomechanics during deep knee flexion.

The implant positioning for kinematically aligned total knee arthroplasty (TKA) differs fundamentally from conventional mechanically aligned TKA. This difference may affect patellofemoral (PF) biomechanics after TKA. This cadaveric study tested the hypothesis that kinematically aligned TKA would restore PF biomechanics to the native condition better than mechanically aligned TKA. Seven pairs (14 knees) of fresh-frozen cadavers were tested. All specimens were mounted on a customized knee-testing system and digitized using a Microscribe 3DLX instrument (Revware Inc., Raleigh, NC, USA) to measure patellar kinematics in terms of patellar varus/valgus rotation, medial/lateral position, flexion/extension rotation and proximal/distal position at knee flexion angles of 0°, 30°, 60°, 90°, and 120°. The medial and lateral PF joint contact pressure distributions at 120° of knee flexion were measured using a K-scan system (Tekscan Inc., Boston, MA, USA). All patellae remained unresurfaced. For each pair, one knee was randomly assigned to kinematically aligned TKA and the other to mechanically aligned TKA performed using the conventional measured resection technique. During kinematically aligned TKA, the amount of femur and tibia resected was equivalent to implant thickness to maintain the patient-specific joint line. All patellar kinematics were measured and compared between the native condition and after surgery. The patellae of mechanically aligned TKA rotated more valgus and was positioned more laterally compared with those of kinematically aligned TKA at knee flexion angles ≥ 90°. Neither the patellar flexion/extension rotation nor the proximal/distal position differed between either prosthetic knee design and the native knee at all flexion angles. The contact pressure distribution between the medial and lateral PF joint after kinematically aligned TKA were similar to those of the native knee, while the lateral PF joint contact pressure after mechanically aligned TKA was higher than that of the native knee (p = 0.038). Kinematically aligned TKA better restores patellar kinematics and PF contact pressure distribution to the native condition than mechanically aligned TKA during deep knee flexion. These findings provide clues to understand why kinematically aligned TKA is associated with less anterior knee pain and better PF functional performance compared to mechanically aligned TKA. Patients undergoing kinematically aligned TKA may experience a more normal feeling during deep knee flexion activities.

Medial and Lateral Patellofemoral Joint Retinaculum Thickness in People With Patellofemoral Pain: A Case-Control Study.

To measure the medial and lateral retinaculum thickness in individuals with and without patellofemoral pain using ultrasound and to assess associations with the symptom duration and function. Medial and lateral patellofemoral joint retinaculum thicknesses of 32 knees (16 with patellofemoral pain and 16 asymptomatic) were measured with B-mode ultrasound at 0.5, 1, and 1.5 cm from the patella border. Participants with patellofemoral pain completed a Kujala questionnaire, and both groups underwent a single-leg squat performance assessment. Two-way analyses of variance (site × group) determined the overall effect, and Cohen d values were calculated to describe the magnitude of the difference for each measurement. The groups were matched for age, height, and weight. Compared to controls, participants with patellofemoral pain had thicker lateral (overall effect, P = .03) and medial (overall effect, P < 0.01) retinacula. No correlations between retinaculum thickness and Kujala scores (lateral retinaculum, r = 0.106 [0.5 cm], -0.093 [1 cm], and -0.207 [1.5 cm]; and medial retinaculum, r = 0.059, 0.109, and -0.219), symptom duration (lateral retinaculum, r = 0.001, -0.041, and 0.302; and medial retinaculum, r = -0.027, -0.358, and -0.346), or single-leg squat performance scores (lateral retinaculum, r = 0.051, 0.114, and 0.046; and medial retinaculum, r = -0.119, -0.292, and 0.011) were observed. Increased lateral and medial retinaculum thickness in individuals with patellofemoral pain compared to controls identifies structural changes that may be associated with the pathogenesis of patellofemoral pain. The absence of a significant correlation between retinaculum thickness and the symptom duration or function further shows a lack of an association between structure and function in individuals with patellofemoral pain.

Relation of meniscus pathology to prevalence and worsening of patellofemoral joint osteoarthritis: the Multicenter Osteoarthritis Study

To determine the relationship of meniscal damage to magnetic resonance imaging (MRI) features of compartment-specific patellofemoral joint (PFJ) osteoarthritis (OA) at baseline and 2 years later. Individuals from a prospective cohort of individuals aged 50-79 with or at risk of knee OA were included. At the 60-month and 84-month study visit, Whole-Organ MRI Score (WORMS) was used to assess meniscal tears and extrusions as well as cartilage damage and bone marrow lesions (BMLs) in the medial and lateral patella and trochlea. Worsening of structural features was defined as any increase in WORMS score from 60 to 84 months. Logistic regression was used to determine the cross-sectional and longitudinal relation of meniscus damage to features of compartment-specific PFJ OA. Relative to knees without lateral meniscal pathology at baseline, those with grades 3-4 lateral meniscal tear and extrusion had greater risk of worsening of cartilage damage in the lateral PFJ 2years later (Risk ratio: 1.7 [95% CI: 1.1-2.7) and (1.7 [1.2-2.5]), respectively. Relative to those without medial meniscal pathology at baseline, those with grades 1-2 (0.6 [0.4-0.9]) and 3-4 (0.7 [0.5-1.0]) medial meniscal tears had lower risk of worsening of BMLs in the medial PFJ 2years later. Meniscal tear and extrusion are associated with increased risk of medial and lateral PFJ OA and more severe meniscal pathology is associated with worsening of PFJ OA 2years later. Lateral meniscal pathology appears to be more detrimental to the lateral PFJ.

Pelvic and Hip Kinematics During Walking in People With Patellofemoral Joint Osteoarthritis Compared to Healthy Age-Matched Controls.

Patellofemoral (PF) joint osteoarthritis (OA) is common, yet little is known about how this condition influences lower-extremity biomechanical function. This study compared pelvis and lower-extremity kinematics in people with and without PF joint OA. Sixty-nine participants (64% women, mean ± SD age 56 ± 10 years) with anterior knee pain aggravated by PF joint-loaded activities (e.g., stair ambulation, rising from sitting, or squatting) and radiographic lateral PF joint OA on skyline radiographs were compared with 18 controls (78% women, mean ± SD age 53 ± 7 years) with no lower-extremity pain or radiographic OA. Knee Injury and Osteoarthritis Outcome Score (KOOS) data were collected from participants with PF joint OA. Quantitative gait analyses were conducted during overground walking at a self-selected speed. Pelvis and lower-extremity kinematics were calculated across the stance phase. Data were statistically analyzed using analyses of covariance, with age and sex as covariates (P < 0.05). Participants with PF joint OA reported a mean ± SD KOOS pain subscale score of 65 ± 15, KOOS symptoms subscale score of 63 ± 16, KOOS activities of daily living subscale score of 73 ± 13, KOOS sports/recreation subscale score of 45 ± 23, and KOOS quality of life subscale score of 43 ± 16. Participants with PF joint OA walked with greater anterior pelvic tilt throughout the stance phase, as well as greater lateral pelvic tilt (i.e., pelvis lower on the contralateral side), greater hip adduction, and lower hip extension during the late stance phase. No differences in knee and ankle joint angles were observed between groups. People with PF joint OA walk with altered pelvic and hip movement patterns compared with aged-matched controls. Restoring normal movement patterns during walking in people with PF joint OA may be warranted to help alleviate symptoms.

The synergistic effect of medial and lateral patellar retinaculum on the stability of patella in full extension

Background: Patellar instability is a common problem. It is unclear that the medial and lateral patellar retinaculum respective effect on patella. The purpose of this study was to evaluate the synergistic effect of medial and lateral patellar retinaculum on the stability of patella. Methods: Eight cadaveric knees were collected. Each of them was performed on patellofemoral joints under five conditions, including normal condition (Group N) and experimental conditions (Group M1, L1, L2, and M2). In Group M1, 2 kg was forced on the normal medial patellofemoral joint using a homemade knee joint immobilization apparatus. In Group L1, 2 kg was forced on the normal lateral patellofemoral joint. In Group L2, the medial retinaculum and the capsule were separated, and the lateral patellar border endured a force of 2 kg. In Group M2, the dissected medial soft tissues were sutured in-situ, and then the lateral retinaculum and the capsule were separated, and the medial patellar border endured a force of 2 kg. Evaluations included CT scan, and the scanned images of these five groups were analyzed for patellar tilt angle (PTA) and the lateral patellar displacement (LPD) values. Results: PTA (°) and LPD (mm) of Group M1 and Group L1 were not significantly different compared to Group N (P≥0.01). PTA values and LPD values of Group L2 and Group M2 increased significantly compared to Group N (P≤0.01). PTA and LPD values of Group L2 showed significant differences compared to Group M2 (P≤0.01). Conclusions: Medial patellar retinaculum prevents LPD and lateral patellar tilt. Lateral patellar retinaculum plays an important role to prevent medial patellar tilt. Medial and lateral retinaculum show synergistic effect to stabilize the patella.

Is superolateral Hoffa's fat pad hyperintensity a marker of local patellofemoral joint disease? - The MOST study.

To determine the relation of superolateral Hoffa's fat pad (SHFP) hyperintensity to cartilage damage and bone marrow lesions (BMLs) in the patellofemoral joint (PFJ) and tibiofemoral joint (TFJ). We used data from the 60 and 84-month study visits from the Multicenter Osteoarthritis (MOST) study. SHFP hyperintensity and Hoffa-synovitis were graded from 0 to 3. Cartilage damage and BMLs were scored in the PFJ and TFJ. Structural damage was defined as: any cartilage damage, full-thickness cartilage damage and any BML. Worsening structural damage was defined as any increase in cartilage and BML scores. Logistic regression was used to determine the relation of SHFP hyperintensity and Hoffa-synovitis (>0) to structural damage, adjusting for age, sex and body mass index (BMI). 1,094 knees were included in the study. Compared to knees without SHFP hyperintensity, those with SHFP hyperintensity had 1.2 (95% Confidence Interval (CI), 1.1-1.4), 1.7 (1.3-2.3) and 1.6 (1.3-1.9) times the prevalence of any cartilage damage, full-thickness cartilage damage, and BMLs in the lateral PFJ respectively, and 1.1 (1.0-1.2), 1.3 (1.0-1.8), and 1.2 (1.0-1.4) times the prevalence of any cartilage damage, full-thickness cartilage damage, and BMLs in the medial PFJ. SHFP hyperintensity was associated with worsening BMLs in the medial PFJ (RR: 1.4 (1.0-1.9)). In general, there was no relation between SHFP hyperintensity and TFJ outcomes. Hoffa-synovitis was associated both cross-sectionally and longitudinally with structural damage, regardless of definition, in all compartments. SHFP hyperintensity may be a local marker of PFJ structural damage.

The Association of Forefoot Varus Deformity with Patellofemoral Cartilage Damage in Older Adult Cadavers

Forefoot alignment may contribute to patellofemoral joint (PFJ) osteoarthritis (OA) via its influence on the closed chain kinematics of the lower limb. The purpose of this cadaveric study was to investigate the relationship between forefoot varus and ipsilateral cartilage damage in the medial and lateral PFJ. Forefoot alignment measurements were obtained from the feet of 25 cadavers (n = 50). Cartilage damage in the medial and lateral PFJ of each knee was scored using the Outerbridge scale. The relative odds of medial and lateral PFJ cartilage damage in limbs with forefoot varus and valgus were determined using logistic regression. The relationship between increasing varus alignment and increasing odds of medial and lateral PFJ cartilage damage was assessed. Of the 51% of limbs with forefoot varus, 91.3% had medial, and 78.3% had lateral PFJ cartilage damage, compared with 54.6% and 68.2% of those with forefoot valgus. The former also had 3.0 times (95% CI 1.2, 7.7) the odds of medial PFJ damage; no association was found with lateral damage (OR 1.4, 95% CI 0.7, 3.0). Feet in the highest tertile of varus alignment had 3.9 times (95% CI 10, 15.3, P = 0.058) the odds of medial PFJ damage as those in the lowest tertile. The results of this study suggest a relationship between forefoot varus and medial PFJ cartilage damage in older adults. As forefoot varus may be modified with foot orthoses, these findings indicate a potential role for orthoses in the treatment of medial PFJ OA. Anat Rec, 300:1032-1038, 2017. © 2016 Wiley Periodicals, Inc.

Does increased femoral antetorsion predispose to cartilage lesions of the patellofemoral joint?

Aims and Objectives:Anatomic variants, instability or incongruence of the patellofemoral joint have been shown to result in pathological patellofemoral stress-patterns and have been described to predispose to patellofemoral cartilage degeneration. Despite the fact that degeneration of the medial patellofemoral facet is seen more frequently when compared to the lateral facet, we need to be aware of patients with abnormal femoral antetorsion and subsequent femoral internal rotation, in whom we detect increased stress patterns and cartilage degeneration of the lateral facet of the patellofemoral joint. Although this entity is well studied in patients with internally rotated femoral components after total knee replacement, there is a lack of scientific evidence in native knees. The purpose of this study was to investigate if there was a relationship between femoral neck antetorsion and the presence and the pattern of osteoarthritis of the patellofemoral joint. It was hypothesized that an increased femoral neck antetorsion correlates with osteoarthritic changes of the lateral facet of the patellofemoral joint and correlates with an increased lateral trochlear height and a decreased sulcus angle.Materials and Methods:Seventy-eight formalin-embedded cadaveric lower extremities from thirty-four subjects with a median age of 74 years (range 60-88) were used. Surrounding soft tissues of the lower limb were removed. The femoral neck antetorsion was measured and referenced to the transepicondylar axis. The height of the medial and lateral facet of the trochlea and the sulcus angle were measured. The location and the degree of patellofemoral cartilage degeneration were recorded. Pearson’s correlation analysis was performed to correlate the femoral neck antetorsion with the measured knee parameters.Results:No significant correlation could be found between the femoral antetorsion and cartilage degeneration of the lateral patellofemoral joint (p = n.s.), the height of the lateral trochlea (p = n.s.), and the sulcus angle (p = n.s.).Conclusion:This study could not document that femoral neck antetorsion and subsequent internal rotation of the distal femur was correlated with the degree of degeneration of the lateral facet of the patellofemoral joint. Based on these findings, femoral internal rotation may only play a minor role in the development of lateral patellofemoral joint degeneration in native knees. In contrast, we are confronted with these cases in our daily clinical practice. To date, valid scientific reports and evidence of different treatment options are limited. Femoral derotational osteotomy could be one treatment option in these cases, but the indication should be considered thoroughly.

Does increased femoral antetorsion predispose to cartilage lesions of the patellofemoral joint?

The purpose of this study was to investigate whether there was a relationship between femoral neck antetorsion and the presence and pattern of osteoarthritis of the patellofemoral joint. It was hypothesized that an increased femoral neck antetorsion (1) correlates with osteoarthritic changes of the lateral facet of the patellofemoral joint and (2) correlates with an increased lateral trochlear height and a decreased sulcus angle. Seventy-eight formalin-embedded cadaveric lower extremities from thirty-nine subjects with a median age of 74years (range 60-88) were used. Surrounding soft tissues of the lower limb were removed. The femoral neck antetorsion was measured and referenced to the transepicondylar axis and the posterior condylar line. The height of the medial and lateral facet of the trochlea and the sulcus angle was measured. The location and the degree of patellofemoral cartilage degeneration were recorded. A Pearson's correlation analysis was performed to correlate the femoral neck antetorsion with the measured knee parameters. No significant correlation could be found between the femoral antetorsion and cartilage degeneration of the lateral patellofemoral joint (n.s.), the height of the lateral trochlea (n.s.) and the sulcus angle (n.s.). This study could not document that the femoral neck antetorsion and subsequent internal rotation of the distal femur correlated with the degree of degeneration of the lateral facet of the patellofemoral joint. Clinically, femoral internal rotation may play a minor role in the development of lateral patellofemoral joint degeneration.

The relation of MRI-detected structural damage in the medial and lateral patellofemoral joint to knee pain: the Multicenter and Framingham Osteoarthritis Studies

To examine the relation of cartilage loss and bone marrow lesions (BMLs) in the medial and lateral patellofemoral joint (PFJ) to knee pain. We categorized the location of full-thickness cartilage loss and BMLs in the PFJ on knee magnetic resonance imaging (MRIs) from the Multicenter Osteoarthritis (MOST) and Framingham Osteoarthritis (FOA) Studies as no damage, isolated medial, isolated lateral, or both medial and lateral (mixed). We determined the relation of MRI lesions in each PFJ region to prevalent knee pain. Differences in knee pain severity were compared among categories of PFJ full-thickness cartilage loss and BMLs using quantile regression. In MOST (n = 1137 knees), compared with knees without full-thickness cartilage loss, knees with isolated lateral or mixed PFJ full-thickness cartilage loss had 1.9 (1.3, 2.8) and 1.9 (1.2, 2.9) times the odds of knee pain, respectively, while isolated medial cartilage loss had no association with knee pain. BMLs in both the medial and lateral PFJ had 1.5 (1.1, 2.0) times the odds of knee pain compared with knees without BMLs. Knee pain severity was lowest in knees with isolated medial PFJ cartilage loss or BMLs. In FOA (n = 934 knees), neither isolated medial nor lateral cartilage loss was associated with knee pain, whereas isolated BMLs in either region were associated with pain. Results were not completely concordant but suggest that knee pain risk and severity is greatest with cartilage loss isolated to (MOST) or inclusive of (MOST and FOA) the lateral PFJ. While BMLs in either the medial or lateral PFJ are related to pain.

The Effect of Tibial Tuberosity Medialization and Lateralization on Patellofemoral Joint Kinematics, Contact Mechanics, and Stability

Background: Tibial tuberosity (TT) transfer is a common procedure to treat patellofemoral instability in patients with elevated TT–trochlear groove (TG) distances. However, the effects of TT lateralization or medialization on patellar stability, kinematics, and contact mechanics remain unclear. Hypothesis: Progressive medialization and lateralization will have increasingly adverse effects on patellofemoral joint kinematics, contact mechanics, and stability. Study Design: Controlled laboratory study. Methods: Eight fresh-frozen cadaveric knees were placed on a testing rig, with a fixed femur and tibia mobile through 90° of flexion. Individual quadriceps heads and the iliotibial band were separated and loaded with 205 N in anatomic directions using a weighted pulley system. Patellofemoral contact pressures and patellar tracking were measured at 0°, 10°, 20°, 30°, 60°, and 90° of flexion using pressure-sensitive film behind the patella and an optical tracking system. The intact knee was measured with and without a 10-N patellar lateral displacement load, and recordings were repeated after TT transfer of 5, 10, and 15 mm medially and laterally. Statistical analysis used repeated-measures analysis of variance, Bonferroni post hoc analysis, and Pearson correlations. Results: Tibial tuberosity lateralization significantly elevated lateral joint contact pressures, increased lateral patellar tracking, and reduced patellar stability (P < .048). There was a significant correlation between mean lateral contact pressure and the TT position (r = 0.810, P < .001) at 10°. Tibial tuberosity medialization reduced lateral contact pressures (P < .002) and did not elevate peak medial contact pressures (P > .11). Conclusion: Progressive TT lateralization elevated lateral contact pressures, increased lateral patellar tracking, and reduced patellar stability. Medial contact pressure and tracking did alter with progressive TT medialization, but the changes were smaller. Clinical Relevance: Lateral patellofemoral joint contact pressures increased with progressive lateralization of the TT; medialization of the TT reduced these effects, restoring patellar stability, and did not cause excessive peak pressures. These data provide a rationale for medial TT transfer surgery in patients with elevated TT-TG distances.

Is Patellofemoral Osteoarthritis Common in Middle‐Aged People With Chronic Patellofemoral Pain?

To document the prevalence of radiographic osteoarthritis (OA) in the medial and lateral patellofemoral (PF) joint compartments relative to the prevalence of tibiofemoral (TF) joint OA in middle-aged and older adults with chronic PF knee pain. A convenience sample of 224 people who volunteered for a clinical trial underwent weight-bearing posteroanterior and skyline knee radiographs of their most symptomatic eligible knee. Radiographic severity in the TF joint and in the medial and lateral PF joint compartments was independently graded by 2 examiners using the Kellgren/Lawrence (K/L) grading system. K/L grades ≥2 were considered evidence of OA. OA was common in this cohort, and the most prevalent pattern was combined TF joint and PF joint OA (n = 98 [44%]), followed by isolated PF joint OA (n = 57 [25%]). Isolated TF joint OA was rare. Overall, more people demonstrated radiographic OA in the PF joint (n = 155 [69%]) than in the TF joint (n = 100 [45%]). The majority of people with PF joint OA had OA in both the medial and lateral PF joint compartments (n = 98 [63%]). Even in people ages <50 years, radiographic OA was common (isolated PF joint OA, 26% [n = 21]; combined TF joint and PF joint OA, 29% [n = 23]). The severity of PF joint OA was similar across men and women. PF joint OA was highly prevalent, more so than TF joint OA, and even in individuals ages <50 years. Further research is needed to elucidate the cause and effect relationship between chronic PF pain and PF joint OA.

Targeted physiotherapy treatment for patellofemoral osteoarthritis: a randomised clinical trial

Targeted physiotherapy treatment for patellofemoral osteoarthritis: a randomised clinical trial

Does medial patellofemoral osteoarthritis matter? the relation of mri-detected structural damage in the medial and lateral patellofemoral joint to knee pain: the most and framingham osteoarthritis studies

s / Osteoarthritis and Cartilage 22 (2014) S7–S56 S54 groups (DEP þ GS, DEP þ placebo, DEP control þ GS) were compared separately with the DEP control þ placebo group as reference group. Results: 687 knees of 347 women with mean age 55.7 years ( 3.2 SD) and mean BMI 32.3kg/m2 ( 4.2 SD) had baseline and follow-up MRI available for analysis. There was no selective drop-out and the women were equally distributed over the 4 groups. ITT analysis showed a significant preventive effect in the DEP þ placebo group on overall progression of meniscus pathology (OR 0.61, 95% CI [0.38 0.99], p-value (p) 0.046). PP analysis showed a significant preventive effect in the DEP þ placebo group on overall progression of meniscus pathology (OR 0.43, 95% CI [0.22 0.84], p 0.014) and on overall progression of bone marrow lesions (OR 0.26, 95% CI [0.08 0.88], p 0.030). The 2 other groups (DEP þGS and DEP controlþGS) showed no significant effects on overall MRI OA-features. When differentiated according to location in the knee, all effects were seen in the medial meniscus or at the medial tibio-femoral compartment. (ITT: medial meniscus extrusion: OR 0.47, 95% CI [0.24 0.91], p 0.025; medial bone marrow lesion: OR 0.33, 95% CI [0.14 -0.77], p 0.011, PP: medial bone marrow lesion: OR 0.13, 95% CI [0.02 0.93], p 0.042). Evaluating the effects of the MRI OA-features on pain, 42 of 347 women (12%) met the definition of incident chronic knee pain in one or both knees (52 of 687 knees (6.7%)). Progression of bonemarrow lesions was significant associated with incident chronic knee pain (OR 2.1, 95% CI [1.02 4.46]). Conclusions: A diet and exercise program has preventive effects on progression of meniscus pathology and on bonemarrow lesions seen on MRI. Progression of bone marrow lesions is associated with incident chronic knee pain. 82 DOES MEDIAL PATELLOFEMORAL OSTEOARTHRITIS MATTER? THE RELATION OF MRI-DETECTED STRUCTURAL DAMAGE IN THE MEDIAL AND LATERAL PATELLOFEMORAL JOINT TO KNEE PAIN: THE MOST AND FRAMINGHAM OSTEOARTHRITIS STUDIES J. Stefanik y, K. Gross z, D. Felson y, J. Niu y, Y. Zhang y, C. Lewis x, N. Segal k, M. Nevitt{, F. Roemer#, A. Guermazi y, T. Neogi y. yBoston Univ., Boston, MA, USA; zMGH Inst. of Hlth.Professions, Boston, MA, USA; xUniv. of Alabama, Birmingham, AL, USA; kUniv. of Iowa, Iowa City, IA, USA; {UCSF, San Francisco, CA, USA; Klinikum Augsburg, Augsburg, Germany Purpose: Contrary to the expectations of biomechanical models, we previously demonstrated a high prevalence of MRI detected cartilage

A case of osteochondritis dissecans of the lateral femoral condyle and patellofemoral joint surface occurring in the same knee.

More than 70 % of osteochondritis dissecans (OCD) lesions in the knee joint occur on the posterolateral surface of the medial femoral condyle, designated as the classic area. Approximately 15–20 % of OCD lesions in the knee joint occur in the inferior–central part of the lateral femoral condyle, and 1 % or less occur on the patellofemoral joint surface [1, 2]. We encountered a patient who simultaneously developed OCD in the inferior–central part of the lateral femoral condyle and in the patellofemoral joint surface.

Prevalence of MRI-detected mediopatellar plica in subjects with knee pain and the association with MRI-detected patellofemoral cartilage damage and bone marrow lesions: data from the Joints On Glucosamine study

BackgroundThe mediopatellar plica is a synovial fold representing an embryonic remnant from the developmental process of the synovial cavity formation in the knee. We aimed to examine the frequency of MRI-detected mediopatellar plica and its cross-sectional association with MRI-detected cartilage damage and bone marrow lesions (BMLs) in the patellofemoral joint (PFJ) in a cohort of subjects with knee pain.Methods342 knees with chronic frequent knee pain were evaluated for MRI-detected mediopatellar plica (type A, B or C according to the modified Sakakibara classification). Cartilage damage (scored 0 to 6) and BMLs (scored 0 to 3) were semiquantitatively assessed in four subregions of the PFJ on MRI. Hoffa-synovitis and effusion-synovitis were graded 0 to 3. Patellar length ratio (PLR), lateral patellar tilt angle (LPTA), bisect offset (BO), and sulcus angle (SA) were measured on MRI. The presence of mediopatellar plica and its association with cartilage damage and BMLs in the PFJ was assessed using logistic regression after adjusting for age, gender, body mass index, PLR, LPTA, BO, SA, and Hoffa- and effusion-synovitis.Results163 (47.7%) knees exhibited mediopatellar plica (76 (22.2%) type A, 69 (20.2%) type B, and 18 (5.3%) type C) on MRI. Significant cross-sectional associations of MRI-detected mediopatellar plica and cartilage damage were observed for the medial patella (adjusted odds ratio (aOR) 2.12, 95% CI 1.23-3.64 for all types combined, and aOR 4.20, 95% CI 1.92-9.19 for type B lesion), but not for the anterior medial femur or the lateral PFJ. No associations were found between the presence of MRI-detected mediopatellar plica and BMLs in any patellofemoral subregion.ConclusionOn MRI, types A and B mediopatellar plicae were commonly observed in this cohort of subjects with knee pain. MRI-detected mediopatellar plica was cross-sectionally associated with higher likelihood of the presence of MRI-detected medial patellar cartilage damage after adjustment for confounders.

Minimum joint space width (mJSW) of patellofemoral joint on standing “skyline” radiographs: test-retest reproducibility and comparison with quantitative magnetic resonance imaging (qMRI)

To assess the intraobserver, interobserver, and test-retest reproducibility of minimum joint space width (mJSW) measurement of medial and lateral patellofemoral joints on standing "skyline" radiographs and to compare the mJSW of the patellofemoral joint to the mean cartilage thickness calculated by quantitative magnetic resonance imaging (qMRI). A couple of standing "skyline" radiographs of the patellofemoral joints and MRI of 55 knees of 28 volunteers (18 females, ten males, mean age, 48.5 ± 16.2years) were obtained on the same day. The mJSW of the patellofemoral joint was manually measured and Kellgren and Lawrence grade (KLG) was independently assessed by two observers. The mJSW was compared to the mean cartilage thickness of patellofemoral joint calculated by qMRI. mJSW of the medial and lateral patellofemoral joint showed an excellent intraobserver agreement (interclass correlation (ICC) = 0.94 and 0.96), interobserver agreement (ICC = 0.90 and 0.95) and test-retest agreement (ICC = 0.92 and 0.96). The mJSW measured on radiographs was correlated to mean cartilage thickness calculated by qMRI (r = 0.71, p < 0.0001 for the medial PFJ and r = 0.81, p < 0.0001 for the lateral PFJ). However, there was a lack of concordance between radiographs and qMRI for extreme values of joint width and KLG. Radiographs yielded higher joint space measures than qMRI in knees with a normal joint space, while qMRI yielded higher joint space measures than radiographs in knees with joint space narrowing and higher KLG. Standing "skyline" radiographs are a reproducible tool for measuring the mJSW of the patellofemoral joint. The mJSW of the patellofemoral joint on radiographs are correlated with, but not concordant with, qMRI measurements.