Widespread Vascularization and Correlation of Glycosaminoglycan Accumulation to Tendon Pain in Human Plantar Fascia Tendinopathy.

BACKGROUND: Plantar fasciitis is a painful tendinous condition (tendinopathy) with a high prevalence in athletes. While a healthy tendon has limited blood flow, ultrasound has indicated elevated blood flow in tendinopathy, but it is unknown if this is related to a de facto increase in the tendon vasculature. Likewise, an accumulation of glycosaminoglycans (GAGs) is observed in tendinopathy, but its relationship to clinical pain is unknown. PURPOSE: To explore to what extent vascularization, inflammation, and fat infiltration were present in patients with plantar fasciitis and if they were related to clinical symptoms. STUDY DESIGN: Descriptive laboratory study. METHODS: Biopsy specimens from tendinopathic plantar fascia tissue were obtained per-operatively from both the primary site of tendon pain and tissue swelling ("proximal") and a region that appeared macroscopically healthy at 1 to 2 cm away from the primary site ("distal") in 22 patients. Biopsy specimens were examined with immunofluorescence for markers of blood vessels, tissue cell density, fat infiltration, and macrophage level. In addition, pain during the first step in the morning (registered during an earlier study) was correlated with the content of collagen and GAGs in tissue. RESULTS: High vascularization (and cellularity) was present in both the proximal (0.89%) and the distal (0.96%) plantar fascia samples, whereas inconsistent but not significantly different fat infiltration and macrophage levels were observed. The collagen content was similar in the 2 plantar fascia regions, whereas the GAG content was higher in the proximal region (3.2% in proximal and 2.8% in distal; P = .027). The GAG content in the proximal region was positively correlated with the subjective morning pain score in the patients with tendinopathy (n = 17). CONCLUSION: In patients with plantar fasciitis, marked tissue vascularization was present in both the painful focal region and a neighboring nonsymptomatic area. In contrast, the accumulation of hydrophilic GAGs was greater in the symptomatic region and was positively correlated with increased clinical pain levels in daily life. CLINICAL RELEVANCE: The accumulation of GAGs in tissue rather than the extent of vascularization appears to be linked with the clinical degree of pain symptoms of the disease.

To allow or avoid pain during shoulder rehabilitation exercises for patients with chronic rotator cuff tendinopathy-Study protocol for a randomized controlled trial (the PASE trial).

BACKGROUND: Rotator cuff (RC) tendinopathy is the most reported shoulder disorder in the general population with highest prevalence in overhead athletes and adult working-age population. A growing body of evidence support exercise therapy as an effective intervention, but to date there are no prospective randomized controlled trials addressing pain as an intervention variable. METHODS: A single-site, prospective, pragmatic, assessor-blinded randomized controlled superiority trial. Eighty-four patients aged 18-55 years with chronic (symptom duration over 3 months) RC tendinopathy are randomized 1:1 to receive shoulder exercise during which pain is either allowed or avoided. The intervention period lasts 26 weeks. During that period, participants in both groups are offered 8 individual on-site sessions with an assigned sports physiotherapist. Participants perform home exercises and are provided with a pain and exercise logbook and asked to report completed home-based exercise sessions and reasons for not completing sessions (pain or other reasons). Patients are also asked to report load and the number of sets and repetitions per sets for each exercise session. The logbooks are collected continuously throughout the intervention period. The primary and secondary outcomes are obtained at baseline, 6 weeks, 26 weeks, and 1 year after baseline. The primary outcome is patient-reported pain and disability using the Shoulder PAin and Disability Index (SPADI). Secondary outcomes are patient-reported pain and disability using Disability Arm Shoulder and Hand short-form (Quick DASH), and shoulder pain using Numeric Pain Rating Scale. Objective outcomes are shoulder range of motion, isometric shoulder muscle strength, pain sensitivity, working ability, and structural changes in the supraspinatus tendon and muscle using ultrasound. DISCUSSION: The results of this study will contribute knowledge about the treatment strategies for patients with RC tendinopathy and help physiotherapists in clinical decision-making. This is the first randomized controlled trial comparing the effects of allowing pain versus avoiding pain during shoulder exercises in patients with chronic RC tendinopathy. If tolerating pain during and after exercise proves to be effective, it will potentially expand our understanding of "exercising into pain" for this patient group, as there is currently no consensus. TRIAL REGISTRATION: ClinicalTrials.gov NCT05124769. Registered on August 11, 2021.

Physiological and clinical effects of low-intensity blood-flow restricted resistance exercise compared to standard rehabilitation in adults with knee osteoarthritis-Protocol for a randomized controlled trial.

INTRODUCTION: Osteoarthritis (OA) is a common disease with high socioeconomical costs. In Denmark, standard rehabilitation (SR) consists of a combination of patient education and supervised physical exercise involving a standardized neuromuscular training program. As an evidence-based alternative, high-load (>70% 1RM) resistance training (HIRT) has shown positive rehabilitation effects in knee-OA but may not be tolerated in all patients (~25%) due to knee joint pain. However, low-load resistance training (20-40% 1RM) with concurrent partial blood-flow restriction (BFR) appears to produce effects similar to HIRT yet involving reduced joint pain during and after exercise. The aim is to examine the effect of low-load BFR training compared to SR on pain, thigh muscle mass and muscle function in adults with knee-OA. We hypothesize that 12 weeks of BFR will lead to superior improvements in pain, muscle mass and mechanical muscle function compared to SR. METHODS AND ANALYSIS: 90 participants diagnosed with radiographic knee-OA will be randomized to either BFR or SR twice a week for 12 weeks. BFR will consist of two selected lower limb strength exercises performed with an inflated pneumatic occlusion cuff. Intervention procedures in SR consist of a full 8 weeks GLA:D course followed by 4 weeks of team group training. Primary outcome variable is the change in KOOS-Pain subscale from baseline to 12 weeks. Secondary outcome variables are changes in pain sensitivity, functional performance, muscle mass and mechanical muscle function. Intention-to-treat and per-protocol analyses will be conducted. One-way analysis of variance will be performed to evaluate between-group changes. Pre-to-post intervention comparisons will be analyzed using a mixed linear model. Regression analysis will be performed to evaluate potential associations between selected outcome variables.

Corticosteroid injection is the best treatment in plantar fasciitis if combined with controlled training.

PURPOSE: Plantar fasciitis is a very common (lifetime incidence ~ 10%) and long-lasting injury with major impact on daily function. Combining corticosteroid injection and physical training (strength training and stretching) was hypothesized to result in a superior effect compared to each treatment separately. METHODS: A single blinded randomized controlled superiority trial conducted in 2013-2014 with a 2-year follow-up (end Sept 2016). 123 consecutive patients (20-65 years) referred to two study centers in Denmark: Institute of Sports Medicine, Bispebjerg Hospital, University of Copenhagen and a private rheumatology clinic with symptoms of plantar fasciitis, and ultrasound measured thickness above 4.0 mm were invited. 25 did not fulfill the inclusion criteria (mainly ultrasound criteria) and 8 refused participation. 90 patients were randomized (pulling sealed envelopes) to 3 groups: (1) 3 months strength training and stretching (n = 30), (2) corticosteroid injections with monthly intervals until thickness < 4.0 mm (maximum 3 injections) (n = 31), (3) combination of the two treatments (n = 29). During the 3 months intervention period load reduction was recommended (cushioning shoes and insoles and abstaining from running and jumping). The main outcome was improvement in Pain at function on a 100-mm VAS score and in Foot Function Index (FFI, range 0-230) at 6 months (Clinicaltrials.gov Identifier: NCT01994759). RESULTS: All groups improved significantly over time, but the combination of corticosteroid injection and training (strength training and stretching) had a superior effect at all time points. The mean difference between the combined treatment and training was 40 points in FFI (95% confidence interval (CI) 63-17 points, p < 0.001) and 20 mm for VAS function pain (CI 35-5 mm, p < 0.01). The mean difference between the combined treatment and corticosteroid injections only was 29 points in FFI (CI 52-7 points, p < 0.01) and 17 mm for VAS function pain (CI 32-2 mm, p < 0.05). All differences were clinically relevant. CONCLUSION: The best treatment for plantar fasciitis is the combination of corticosteroid injections and training (strength training and stretching). This combined treatment is superior both in the short- and in the longterm. Corticosteroid injections combined with controlled training are recommended as first line treatment in patients with plantar fasciitis. LEVEL OF EVIDENCE: 1.

Navicular bone position determined by positional MRI: a reproducibility study.

OBJECTIVE: To examine intraobserver, interobserver and between-day reproducibility of positional MRI for evaluation of navicular bone height (NVH) and medial navicular position (MNP). MATERIALS AND METHODS: Positional MRI (pMRI) of the foot was performed on ten healthy participants (0.25 T G-scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%). RESULTS: Intraobserver and interobserver reliability was "substantial" in both supine and standing position (ICC 0.86-0.98) and showed good agreement (LOA% 4.9-14.7 %). Between-day reliability of navicular height and medial navicular position in standing position remained substantial (ICC 0.85-0.92) with adequate agreement (LOA% 8.3-19.8 %). In supine position between-day reliability was "moderate" for NVH (ICC 0.72) and "slight" for MNP (ICC 0.39). Agreement remained adequate between-days for MNP in supine position (LOA% 17.7 %), but it was less than adequate for NVH in supine position (LOA% 24.2 %). CONCLUSION: Navicular height and medial navicular position can be measured by pMRI in a very reproducible manner within and between observers. Increased measurement variation is observed between-days in supine position, which may be due to small positional differences or other unknown biomechanical factors.

Ultrasonography as a prognostic and objective parameter in Achilles tendinopathy: a prospective observational study.

OBJECTIVES: To study prospectively whether structural changes determined by ultrasound scanning (US) can be used as prognostic markers for outcome in patients with symptomatic Achilles tendinopathy (AT) and to investigate whether there exists an association between US findings and pain measured by visual analog scale (VAS) and a general assessment score (GA). METHODS: 92 consecutive patients with AT symptoms were recruited from two outpatient clinics in rheumatology. The patients underwent a conservative treatment protocol consisting of reduced activities, controlled rehabilitation including eccentric exercises of the calf muscles and if needed supplemented with corticosteroid injections. The patients were examined clinically and by US (tendon thickness, hyper- and hypoechogenicity, calcification, bursitis, calcaneusspure, tenosynovitis, gray scale and color Doppler focusing on increased flow intra- or peritendinous). The clinical and US examination were performed at entry, 1, 2, 3 and at 6 month. RESULTS: 42 women and 50 men were included (mean age of 47 years). They had symptoms for more than 13 months and a symptomatic Achilles tendon mean thickness of 7.4±2.3mm. Heterogeneity at the initial examination was found to be a prognostic marker for the clinical outcome. Tendon thickness, hypoechogenicity and increased flow at any time point were significantly correlated to pain at function, palpatory pain and morning pain at the same time points. A reduction in tendon thickness was statistically associated with a decrease in palpatory pain. CONCLUSION: Heterogeneity is a prognostic marker in AT. Tendon thickness, hypoechogenicity and increased Doppler activity can be used as objective outcome parameters for the treatment effect of AT.