Persistent Patellofemoral Pain Research Articles

The relationship of behavioral and psychological traits with pain sensitivity in females with patellofemoral pain: A cross-sectional study

ObjectiveThe purpose of this study was to describe the relationship between behavioral and psychological traits with indicators of central sensitization in female runners with patellofemoral pain (PFP), and to determine if behavioral and psychological traits improve with strength training. DesignCross-sectional study. SettingUniversity laboratory. ParticipantsTwenty-eight active females (mean age 32 ± 8.1 years) with PFP completed testing at baseline, 8 weeks (post intervention), and 12 weeks. Main outcome measuresBehavioral and psychological questionnaires included the General Anxiety Disorder-7, Patient Health Questionairre-9, Pain Catastrophizing Scale, Tampa Scale of Kinesiophobia-11, and Central Sensitization Inventory. Quantitative sensory testing (QST) measures were also collected. After baseline testing, subjects were instructed in a hip and knee strengthening intervention to be completed twice daily over 8 weeks. ResultsA statistically significant improvement was found at 12 weeks for anxiety (p = .015; ηp (Boling et al., 2010) = 0.099) and kinesiophobia (p = .041; ηp (Boling et al., 2010) = 0.076). There was no significant improvement for depression, catastrophizing, or subjective central sensitization. No significant correlations were found between any of the behavioral and psychological questionnaires with baseline QST variables. ConclusionsNo relationship was found for behavioral and psychological characteristics with QST measures in female runners with persistent PFP.

Are Physical Function and Fear of Movement Risk Factors for Patellofemoral Pain? A 2-Year Prospective Study.

To determine (1)whether physical function and fear of movement are prospectively associated with the risk of females developing patellofemoral pain (PFP) and (2)whether they change following development of PFP. Prospective observational study. A total of 114 asymptomatic females (18-22y old) completed assessment of physical function (forward step-down test and single-leg hop for distance) and fear of movement using the Tampa Scale for Kinesiophobia at baseline and 2-year follow-up. Presence of symptoms of PFP was monitored bimonthly. Ninety participants (retention rate = 79%) completed the 2-year follow-up assessment, with 27 (24% of the cohort) developing PFP. Physical function, including forward step-down test (P = .659) and single-leg hop for distance (P = .825), and fear of movement (P = .479) were not associated with the risk of developing PFP. Females who developed PFP presented with reduced forward step-down repetitions (mean difference = 2.8; 95% confidence interval, 0.2 to 5.3) and single-leg hop for distance (10.2; 95% confidence interval, 2.7 to 17.7cm) at 2-year follow-up. There was no statistically significant difference between those who did and did not develop PFP for fear of movement (-3.4; 95% confidence interval, -7.0 to 0.2). Physical function and fear of movement were not associated with the risk of developing PFP in young females. However, the change over time in the step-down and single-leg hop for distance tests may suggest that, even in the early stages of PFP, young females present impaired physical function compared with females who did not develop symptoms. Fear of movement may develop due to persistent PFP, and does not appear to be a risk factor or key feature in females with PFP of short symptoms duration.

SY1.7. Rewiring pain through non-invasive brain stimulation

Chronic pain occurs when pain in an injured tissue persists beyond the normal recovery time. This crippling condition causes significant burden to the individual and to society. Despite years of research, treatments for chronic pain are largely ineffective, which may in part be due to a lack of understanding of the mechanisms that underpin chronic pain. There is increasing evidence that chronic musculoskeletal pain is associated with sensorimotor dysfunction, and that targeting the mechanisms associated with this dysfunction using non-invasive brain stimulation may alleviate symptoms of pain. This presentation will highlight studies investigating the manifestation of sensorimotor neuroplasticity in a range of musculoskeletal pain conditions such as low back pain, persistent elbow pain and persistent patellofemoral pain. These studies have used transcranial magnetic stimulation and electromyography methodologies and have shown that the organisation of the sensorimotor cortical representation of the pain afflicted muscle is altered. Novel treatment studies will then be reviewed. These studies have attempted to “rewire” pain by targeting sensorimotor cortical organisation using ‘top-down’ (non-invasive brain stimulation) and “bottom-up” approaches (trans-spinal stimulation, peripheral electrical stimulation and exercise). The potential limitations of these approaches will then be discussed including the large variation in responsiveness to treatment, and the need for individualized treatment. Indeed, our work using transitional pain models in healthy human subjects has shown that inter-individual differences in sensorimotor function in a pain free state and during persistent pain, can predict the severity of pain. It will be argued that tailoring treatment in accordance with an individual’s sensorimotor function in the early stages of pain may facilitate the diagnosis, prevention and treatment of pain. A planned project will be presented which will focus on modulating pain in accordance with these individual differences using non-invasive brain stimulation.

Psychological and pain profiles in persons with patellofemoral pain as the primary symptom.

Patellofemoral pain (PFP) is defined biomechanically, but is characterized by features that fit poorly within nociceptive pain. Mechanisms associated with central sensitization may explain why, for some, symptoms appear nociplastic. This study compares psychological and somatosensory characteristics between those with persistent PFP and controls. A total of 150 adults with PFP were compared to 61 controls. All participants completed a survey evaluating participant characteristics, PFP-related constructs and psychological factors: anxiety, depression, pain catastrophizing, kinesiophobia, pain self-efficacy. Participants also attended a session of somatosensory testing, which included knee and elbow thermal and mechanical detection and pain thresholds, conditioned pain modulation (CPM), and temporal summation of pain (TSP). Differences were evaluated using analysis of covariance (sex as covariate). Multivariate backward stepwise linear regression examined how psychological and somatosensory variables relate to PFP (knee injury and osteoarthritis outcome score-patellofemoral [KOOS-PF]). The PFP group had multimodal reduced pain thresholds at the knee and elbow (standardized mean difference [SMD], p: 0.86-1.2, <.001), reduced mechanical detection at the elbow (0.43, .01) and higher TSP (0.41, .01). CPM was not different. Psychological features demonstrated small effects (0.47-0.59, 0.01-0.04). The PFP group had a 55% (95% CI: 0.47-0.62) risk of kinesiophobia and an 11% (0.06-0.15) reduced pain self-efficacy risk. Kinesiophobia, knee pressure pain threshold, pain self-efficacy and pain catastrophizing explained 40% of KOOS-PF variance (p=<.001). Widespread hyperalgesia and evidence of symptom amplification may reflect nociplastic pain. Clinicians should be aware that kinesiophobia and the nociplastic pain may characterize the condition. (a) Individuals with PFP have widespread reduced pain thresholds to pressure and thermal stimuli. (b) Mechanically induced pain is likely amplified in those with PFP. (c) Pain-related fear is highly prevalent and helps explain PFP-related disability.

The impact of radiographic patellofemoral osteoarthritis on symptomatic, physical and psychosocial features in individuals with persistent patellofemoral pain

Purpose: Patellofemoral pain (PFP) is a common, burdensome condition across the lifespan, that often starts in adolescence and persists into adulthood. There is increasing suggestion that persistent PFP may be related to patellofemoral osteoarthritis (PFOA). Understanding the characteristics of people with persistent PFP, and how these relate to the presence of radiographic PFOA, may help us develop targeted treatments to improve patient outcomes. The aim of this study was to explore how symptomatic, psychosocial and physical characteristics differ in those with persistent PFP based on the presence or absence of radiographic PFOA.

Immediate effects of foot orthoses on gait biomechanics in individuals with persistent patellofemoral pain

BackgroundThe efficacy of foot orthoses in reducing patellofemoral pain (PFP) is well documented; however, the mechanisms by which foot orthoses modulate pain and function are poorly understood. Research questionThis within-subject study investigated the immediate effects of foot orthoses on lower limb kinematics and angular impulses during level walking and stair ambulation in individuals with persistent PFP. MethodsForty-two participants with persistent PFP (≥3 months duration) underwent quantitative gait analysis during level walking, stair ascent and stair descent while using: (i) standard running sandals (control); and (ii) standard running sandals fitted with prefabricated foot orthoses. Hip, knee, and ankle joint kinematics and angular impulses were calculated and statistically analyzed using paired t-tests (p < 0.05). ResultsRelative to the control condition, foot orthoses use was associated with small but significant decreases in maximum ankle inversion angles during walking (mean difference [95% confidence interval]: −1.00° [−1.48 to −0.53]), stair ascent (−1.06° [−1.66 to −0.45]) and stair decent (−0.94° [−1.40 to −0.49]). Foot orthoses were also associated with decreased ankle eversion impulse during walking (−9.8Nms/kg [−12.7 to −6.8]), and decreased ankle dorsiflexion and eversion impulse during stair ascent (−67.6Nms/kg [−100.7 to −34.6] and −17.5Nms/kg [−23.6 to −11.4], respectively) and descent (−50.4Nms/kg [−77.2 to −23.6] and −11.6Nms/kg [−15.6 to −7.5], respectively). Ankle internal rotation impulse decreased when participants ascended stairs with foot orthoses (−3.3Nms/kg [−5.4 to −1.3]). Limited changes were observed at the knee and hip. SignificanceIn individuals with persistent PFP, small immediate changes in kinematics and angular impulses – primarily at the ankle – were observed when foot orthoses were worn during walking or stair ambulation. The clinical implications of these small changes, as well as the longer-term effects of foot orthoses on lower limb biomechanics, are yet to be determined.

Prevalence of Radiographic and Magnetic Resonance Imaging Features of Patellofemoral Osteoarthritis in Young and Middle-Aged Adults With Persistent Patellofemoral Pain.

To describe the prevalence of radiographic features of patellofemoral (PF) osteoarthritis (OA) in adults with persistent PF pain, to describe the prevalence of magnetic resonance imaging (MRI)-defined PF OA and compare it to that in age- and sex-matched controls, and to explore the prevalence of radiographic and MRI-defined PF OA across age, sex, and body mass index (BMI) groups. This cross-sectional study included 84 individuals with PF pain ≥3 months duration and 26 age- and sex-matched controls. In participants with PF pain, posteroanterior, lateral, and skyline radiographs were obtained. Radiographic OA features were scored using Kellgren/Lawrence (K/L) criteria and a radiographic atlas, with K/L grade ≥2 defined as OA, and K/L grade 1 as early OA. Both groups underwent 3.0 Tesla MRI scans, scored using the MRI Osteoarthritis Knee Score criteria. Compartmental prevalence of MRI OA features was based on cartilage lesions, bone marrow lesions (BMLs), and osteophytes. Overall, 20 participants (24%) with PF pain had radiographic PF OA (K/L grade ≥2), and 36 participants (43%) had early PF OA (K/L grade 1). MRI-defined PF OA was more prevalent in participants with PF pain (16-29%) than in controls (4-12%), irrespective of how PF OA was defined. Within the PF pain group, the prevalence of PF OA on radiographs and MRI was greater in participants who were older or female or who had a higher BMI. Features of radiographic and MRI-defined PF OA were evident in 20-30% of adults ages 26-50 years with persistent PF pain, with greater prevalence observed in those who were older, or female, or who had a higher BMI. MRI-defined PF OA was more prevalent in individuals with PF pain than in pain-free controls, especially when defined as a full-thickness cartilage lesion with BML.

Young to middle-aged adults with persistent patellofemoral pain demonstrate similar pain, disability and knee-related quality of life as older adults with patellofemoral osteoarthritis

Young to middle-aged adults with persistent patellofemoral pain demonstrate similar pain, disability and knee-related quality of life as older adults with patellofemoral osteoarthritis

A cross-sectional study of somatosensory and psychological factors in patellofemoral pain

Introduction: Patellofemoral pain is considered to be a load-related condition, conceptualized biomechanically and maintained by ongoing nociceptive input. For many, the condition persists, suggesting other mechanisms beyond nociception may be involved. This study compared psychological factors and somatosensory characteristics in those with persistent patellofemoral pain and asymptomatic controls.

Isolated medial patellofemoral ligament reconstruction for posttraumatic recurrent lateral patellar instability. How can it be successful?

Background: Injury to the medial patellofemoral ligament (MPFL) occurs in nearly all cases of traumatic patellar dislocation. Reconstruction of the MFPL is the main treatment of such conditions. Other anatomical abnormalities that predispose to lateral patellar instability should be excluded for successful outcome after isolated MPFL reconstruction. Methods: In the period from June 2012 to January 2015, 18 patients with had recurrent posttraumatic unilateral lateral patellar instability caused by an isolated MPFL tear that was reconstructed with a semitendinosus autograft to reconstruct MPFL. The mean follow-up period was 24 mo. Patients with isolated MPFL tears were carefully chosen through a series of clinical and radiographic workups. The technique was done through a less invasive approach, with the graft fixed to the femur by a bioabsorbable interference screw and to the patella; the graft was passed through two transverse tunnels making a laterally based loop. Results: No dislocations or apprehension was recorded. Furthermore, there were no major complications, only persistent patellofemoral pain in patients with preoperative osteochondral patellar injuries. Kujala functional score improved from 35.6 preoperatively to 90.4. Conclusions: Careful patient selection and proper surgical technique are the two main items for patellar stabilization with isolated MPFL reconstruction.

Primary Motor Cortex Organization Is Altered in Persistent Patellofemoral Pain.

Reorganization of the primary motor cortex (M1) may be a feature of persistent patellofemoral pain (PFP), but no studies have investigated M1 organization in this condition. Here we aimed to examine the organization of the M1 representation of the quadriceps muscles in people with PFP and healthy controls. Using a cross-sectional design, the M1 representation of the rectus femoris, vastus lateralis, and vastus medialis was mapped using transcranial magnetic stimulation in 11 individuals with PFP and 11 controls. Measures of pain severity were also made. Individuals with PFP had reduced map volumes (P < 0.001) and an anterior shift in the M1 representation (P = 0.03) across all three quadriceps muscles compared with controls. Greater overlap of the M1 representation (P = 0.02) and a reduction in the number of discrete cortical peaks (P = 0.009) across all three quadriceps muscles were also observed in individuals with PFP compared with controls. There was no relationship between altered M1 organization and pain in PFP. These findings provide evidence of altered M1 organization in individuals with PFP compared with healthy controls. Notably, no difference in M1 organization was observed for the medial and lateral heads of the quadriceps in PFP. These data have relevance for our understanding of the pathophysiology of PFP and for the design of future treatments that aim to target M1 in this condition.

The Effectiveness of Multimodal Care for Soft Tissue Injuries of the Lower Extremity: A Systematic Review by the Ontario Protocol for Traffic Injury Management (OPTIMa) Collaboration

ObjectiveThe purpose of this systematic review was to evaluate the effectiveness of multimodal care for the management of soft tissue injuries of the lower extremity. MethodsWe systematically searched MEDLINE, EMBASE, PsycINFO, CINAHL, and the Cochrane Central Register of Controlled Trials from 1990 to 2015. Random pairs of independent reviewers screened studies for relevance and critically appraised eligible studies using the Scottish Intercollegiate Guidelines Network criteria. We included studies with a low risk of bias in our best evidence synthesis. ResultsWe screened 6794 articles. Six studies had a low risk of bias and addressed the following: plantar heel pain (n = 2), adductor-related groin pain (n = 1), and patellofemoral pain (n = 3). The evidence suggests that multimodal care for the management of persistent plantar heel pain may include mobilization and stretching exercise. An intensive, clinic-based, group exercise program (strengthening, stretching, balance, agility) is more effective than multimodal care for the management of adductor-related groin pain in male athletes. There is inconclusive evidence to support the use of multimodal care for the management of persistent patellofemoral pain. Our search did not identify any low risk of bias studies examining multimodal care for the management of other soft tissue injuries of the lower extremity. ConclusionA multimodal program of care for the management of persistent plantar heel pain may include mobilization and stretching exercise. Multimodal care for adductor-related groin pain is not recommended based on the current evidence. There is inconclusive evidence to support the use of multimodal care for the management of persistent patellofemoral pain.

Antero-medialisation of the tibial tubercle for patellar instability

We reviewed 19 patients (24 knees) with patellofemoral instability treated surgically with antero-medialisation of the tibial tubercle and lateral retinacular release. Twenty-two knees had recurrent patellar dislocation and two patellar subluxation. Lateral retinacular release was performed arthroscopically in 15 knees. Average follow-up was 52 (16-86) months. There was one postoperative haemarthrosis and one failed fixation, which needed surgical revision. The average Lysholm score improved from 63.3 to 98 and only one knee had persistent patello-femoral pain postoperatively. The patellar tilt angle improved from 9.4 degrees to 5.5 degrees . There were no redislocations. We find that the surgical technique produces a consistent correction of patellar instability, but long-term studies are needed to confirm whether it can prevent arthritic degeneration.

KNEE INJURY - JAZZ/THEATRICAL DANCE

HISTORY 17 y/o female theatrical/jazz dancer presented to a sports medicine clinic two months after sustaining her fifth left patellar dislocation in a two-year span. She was doing well five months prior, when she had this most recent dislocation that occurred while she was standing still doing an upper body dance routine. Her patella was reduced in the ER with normal post reduction films. She left the ER with a patellar cut-out brace w/o lateral buttress and no instructions on proper use/weaning. She was started on a very basic strengthening program that included only quad extension sets, isometric quad sets and lunges. She felt that the knee was unstable and had significant retro-patellar pain that precluded almost all activity. Other significant medical problems included HTN and recently diagnosed sponge kidney disease. PHYSICAL EXAMINATION Significant atrophy noted w/in entire left quadriceps group. There was a five-centimeter difference in thigh circumference when compared to the right. The calf on the left was 1.5 cm smaller as compared to the right. ROM of the left knee revealed 30–35 degrees of hyperextension & 70–75 degrees of flexion. There was a smaller degree of genu recurvatum noticed on the right. There was tightness at her end limit of left knee flexion along the anterior inferior patella. Increased laxity in the left patella as compared to the right. Slight medial joint line tenderness. No notable effusion or erythema of the knee. No laxity of the ACL, PCL, MCL, or LCL was noted. MMT was significant for left hip flexors 4+-5/5, left knee extensors 3–3+/5, left ankle dorsiflexors 4+/5, and left hamstrings 4/5. The left EHL, EDL, & all muscle groups tested in the right lower extremity were 5/5 strength. Pinprick in L1 to S2 dermatomes and in all peripheral nerve distributions was intact and symmetrical bilaterally. Reflexes were a brisk 3+ at the left patella, ankle, and internal hamstrings. DIFFERENTIAL DIAGNOSIS Status post Left patellar dislocation & persistent patellofemoral pain. Disuse atrophy. Left femoral nerve injury. Left lumbrosacral plexopathy. Left L4 radiculopathy R/O meniscal tear. R/O ACL tear R/O osteochondritis Dissecans. TEST AND RESULTS MRI Left thigh (9 days post injury): Large knee joint effusion. Medial patellar & lateral femoral bone contusions. Complete tear of medial retinaculum. Abnormal placement of lateral meniscus with a tear at lateral joint line & possible meniscal cyst inferior to lateral meniscus displacement. MRI Left thigh, STIR sequencing (4 months post injury): Abnormal signal within vastus medialis, lateralis and intermedius musculature w/o evidence of fatty atrophy. No abnormality within neurovascular bundle. Septate uterus. EMG/NCS left lower extremity (2 months post injury): Normal saphenous sensory response. Needle EMG - Abnormal spontaneous activity in vastus medialis (fibs and PSWs) & vastus lateralis (PSWs) with normal motor units. Normal exam of iliopsoas, tibialis anterior, adductor longus, & medial gastrocnemius muscles. EMG left lower extremity (6 months post injury): Needle EMG — Few polyphasics & reduced recruitment pattern seen in left vastus lateralis & rectus femoris. FINAL WORKING DIAGNOSIS Left patellar dislocation. Acute femoral neuropathy distal to inguinal ligament & saphenous sensory branch d/t patellar dislocation. Sponge kidney disease (no apparent impact on patellofemoral pathology). TREATMENT AND OUTCOMES Patellar buttress brace. McConnell taping. Quadriceps strengthening exercises: VMO >VL strengthening. Adductor, hip flexor, & TFL strengthening. Slow quadriceps & TFL stretching to increases knee flexion. Gait mechanics training to reduce genu recurvatum (focus on reverse origin-activation of gastrocnemius & eccentric activation of hamstrings). Proprioceptive & balance training Complete abstinence from the use of e-stim & U/S. Patient referred to orthopedic surgeons to evaluate for possible realignment if no femoral recovery and/or recurrent dislocations. Continued persistent atrophy, but slowly advancing ADLs & social activities. Await progress after activity increases.

Anteromedial tibial tubercle transfer without bone graft

We followed 30 patients for more than 2 years after anteromedial tibial tubercle transfer for persistent patellofemoral pain associated with patellar articular degeneration. Twelve of these patients were followed more than 5 years. We report 93% good and excellent results subjectively and 89% good and excellent results objectively. The quality of improvement was sustained in all 12 of the patients who were evaluated again after more than 5 years from surgery. When examined separately, 75% of those patients with advanced patellar arthrosis achieved a good result; none of these patients achieved an excellent result. Postoperative continuous passive motion has markedly reduced the incidence of stiffness. Serious complications such as compartment syndrome, infection, and skin slough were avoided completely in 51 consecutive cases. Patellofemoral contact pressure studies in five cadaver knees have shown that anteromedial tibial tubercle transfer can provide substantial reduction of patellofemoral contact stress while helping to balance medial and lateral facet pressures. This surgical procedure is mechanically and clinically successful for alleviating intractable pain related to patellar malalignment and articular degeneration. This procedure enables the majority of appropriately selected patients with malalignment and patellar articular degeneration to resume increased levels of activity with substantially diminished pain.

The Evaluation of Patellofemoral Pain Using Computerized Tomography

There are well-recognized limitations of conventional axial radiographs of the patellofemoral joint in assessing patients with peripatellar pain, particularly in the first 20 degrees of knee flexion. Computerized tomography (CT) was used, therefore, to evaluate 20 patients with persistent patellofemoral pain and ten asymptomatic volunteers. Multiple midpatellar images were obtained between zero degrees and 30 degrees -40 degrees (sometimes 40 degrees) of flexion, with and without maximal quadriceps contraction. Three distinct patterns of malalignment were identified. When compared to controls, 11 patients had lateralized patellae based on high-congruence angles in extension. With progressive flexion to 30 degrees, all but one reduced into the trochlea. This group was subdivided into those lateralized with or without associated patellar tilting. There were seven patients whose patellae progressively tilted between zero degrees and 30 degrees of flexion while remaining centered in the trochlea. Anatomic differences demonstrated by CT appear to be a factor in distinguishing these groups. Computerized tomography may be the optimal method of radiographically evaluating the patellofemoral joint. Patients have been identified with lateralized patellae in extension that subsequently become congruent by 30 degrees of flexion and therefore may not be appreciated on traditional radiographs. An awareness of different patterns of malalignment is a significant advantage of computerized tomography when planning selective surgical realignment for these patients.

The arthroscopic treatment of chondromalacia patellae.

Three hundred and nineteen patients who had chondromalacia patellae and persistent patellofemoral pain after six months of conservative management underwent arthroscopy and arthroscopic surgery. The results in four aetiological groups were reviewed at one year and five years after operation. Morbidity was minimal. Lavage produced early remission in all groups. Shaving offered a particular advantage in the post-traumatic group. Lateral release plus shaving and lavage was beneficial in the group with maltracking patellae and in half of the idiopathic group. In the group with unstable patellae, lateral release produced good results in only one in four patients. In conclusion, we consider that arthroscopic surgery has a useful role to play in the management of chondromalacia patellae.

Is chondromalacia patellae a separate clinical entity?

The articular cartilage of the patella was studied in 100 knees at necropsy. In twenty-one of these knees the cartilage changes were related to the trabecular architecture of the underlying bone. It would appear that the initiation and location of cartilage damage and its rate and degree of progression are related to the relative stiffness of the underlying cancellous bone. On the basis of our observations we suggest that the diagnosis "chondromalacia of the patella" should be reserved for patients with asymptomatic or transiently symptomatic fibrillation of the articular cartilage of the central medial patellar facet. Those patients with persistent patellofemoral pain should be considered to have some other syndrome.