Carsten Mølgaard

Patellofemoral Pain Syndrome and Its Association with Hip, Ankle, and Foot Function in 16- to 18-Year-Old High School Students: A Single-blind Case-control Study

BACKGROUND An increased pronated foot posture is believed to contribute to patellofemoral pain syndrome (PFPS), but the relationship between these phenomena is still controversial. The objectives of this study were to investigate the prevalence of PFPS in high school students and to compare passive internal and external hip rotation, passive dorsiflexion, and navicular drop and drift between healthy high school students and students with PFPS. METHODS All 16- to 18-year-old students in a Danish high school were invited to join this single-blind case-control study (N = 299). All of the students received a questionnaire regarding knee pain. The main outcome measurements were prevalence of PFPS, navicular drop and drift, passive ankle dorsiflexion, passive hip rotation in the prone position, and activity level. The case group consisted of all students with PFPS. From the same population, a randomly chosen control group was formed. RESULTS The prevalence of knee pain was 25%. Of the 24 students with knee pain, 13 were diagnosed as having PFPS. This corresponds to a PFPS prevalence of 6%. Mean navicular drop and drift were higher in the PFPS group versus the control group (navicular drop: 4.2 mm [95% confidence interval (CI), 3.2-5.3 mm] versus 2.9 mm [95% CI, 2.5-3.3 mm]; and navicular drift: 2.6 mm [95% CI, 1.6-3.7 mm] versus 1.4 mm [95% CI, 0.9-2.0 mm]). Higher passive ankle dorsiflexion was also identified in the PFPS group (22.2° [95% CI, 18°-26°] versus 17.7° [95% CI, 15°-20°]). CONCLUSIONS This study demonstrated greater navicular drop, navicular drift, and dorsiflexion in high school students with PFPS compared with healthy students and highlights that foot posture is important to consider as a factor where patients with PFPS diverge from healthy individuals.

High prevalence of foot problems in the Danish population: A survey of causes and associations

OBJECTIVE To determine the prevalence and severity of foot pain and deformity and the associated risk of leg and low back pain. METHOD A cross-sectional postal survey was conducted among a randomly selected sample of 2100 adult Danish inhabitants (18-80 years of age). Participants reported 1-month period prevalences of foot, lower leg, knee, hip and back pain. RESULTS Responder rate was 79.6%. Prevalence of foot pain was 30.4% with a total of 55.9% reporting pain in the foot, leg or back lasting more than 1 day within the previous month. Foot pain lasting more than 1 month was experienced by 16.2% and 11.9% had pain lasting more than 1 year. The prevalence of self-reported pes planus or pes cavus was 17.9%. There was a significant association between foot pain and pain elsewhere in the leg and low back. Self-reported foot deformity was significantly associated with foot pain. Women had a significantly higher prevalence of foot pain and Body Mass Index was associated with foot pain in women but not in men. CONCLUSIONS Foot pain is highly prevalent and associated with foot deformity and leg and low back pain. More attention should be focused on foot pain and foot deformity. It is suggested that clinical examination of leg and low back pain should include foot examination.

High-load strength training improves outcome in patients with plantar fasciitis: A randomized controlled trial with 12-month follow-up

The aim of this study was to investigate the effectiveness of shoe inserts and plantar fascia‐specific stretching vs shoe inserts and high‐load strength training in patients with plantar fasciitis. Forty‐eight patients with ultrasonography‐verified plantar fasciitis were randomized to shoe inserts and daily plantar‐specific stretching (the stretch group) or shoe inserts and high‐load progressive strength training (the strength group) performed every second day. High‐load strength training consisted of unilateral heel raises with a towel inserted under the toes. Primary outcome was the foot function index (FFI) at 3 months. Additional follow‐ups were performed at 1, 6, and 12 months. At the primary endpoint, at 3 months, the strength group had a FFI that was 29 points lower [95% confidence interval (CI): 6–52, P = 0.016] compared with the stretch group. At 1, 6, and 12 months, there were no differences between groups (P > 0.34). At 12 months, the FFI was 22 points (95% CI: 9–36) in the strength group and 16 points (95% CI: 0–32) in the stretch group. There were no differences in any of the secondary outcomes. A simple progressive exercise protocol, performed every second day, resulted in superior self‐reported outcome after 3 months compared with plantar‐specific stretching. High‐load strength training may aid in a quicker reduction in pain and improvements in function.

Exercise therapy and custom-made insoles are effective in patients with excessive pronation and chronic foot pain—A randomized controlled trial

BACKGROUND Excessive foot pronation is a causal mechanisms described in relation to injuries of the lower extremities. Evidence to support an effective treatment is insufficient. OBJECTIVE To investigate the effect of exercise and custom-made insoles to patients with excessive pronation and chronic pain conditions in the foot at short and long term follow-up. METHODS Single blinded Randomized Controlled Trial with 80 subjects randomized: (1) Standard Intervention, (2) Insole, (3) Exercise, and (4) Insole+Exercise. Exercise - 12 week supervised program. Insoles - individually molded and posted. Pain was measured during walking, resting and running. Static and dynamic foot postures were measured as calcaneal angle, navicular drift, drop and height. RESULTS The average duration of foot pain was 7.3 years. There was a significant pain reduction during walking within all groups at 4 and 12 months follow-up. No differences were seen between groups in any of the pain parameters. Weak correlations between changes in pain and foot postures were observed at baseline and one-year follow-up. CONCLUSION A significant pain reduction was seen in all groups, none of the treatment modalities seem to be superior with the number of patients included. Compliance in the standard intervention group was a concern at 12 months.

Potential interaction of experimental knee pain and laterally wedged insoles for knee off-loading during walking

BACKGROUND Laterally wedged insoles are one of the gait modifications potentially slowing down progression of medial knee osteoarthritis. Clinical studies have, however, found large individual differences in the biomechanical effect and an insufficient pain reduction. To clarify if and how pain mediates mechanical changes during gait the current study investigated how acute experimental knee pain changes the mechanical effect of laterally wedged insoles in healthy subjects during walking. METHODS 3D gait analysis was carried out for twelve healthy individuals. The study followed a cross-over design and data were collected with both a neutral and a 10-degree laterally wedged insole with experimental pain induced by hypertonic and isotonic saline injections into the infrapatellar fat pad. Peak knee adduction moment was the primary outcome. A repeated ANOVA (analysis of variance) was used to evaluate the relationship between the factors wedge, condition and test number. FINDINGS Wedges significantly reduced peak knee adduction moment but experimental knee pain did only marginally affect its magnitude in either condition. While frontal plane mechanics were relatively unaffected by pain, the sagittal plane knee extension moment increased with laterally wedging (P=0.008), whereas late knee flexion moment was reduced by experimental knee pain (P=0.04). INTERPRETATION The effect of laterally wedged insoles in attenuating knee adduction moment during walking is independent of experimental knee pain. The present study provides evidence that subjects with experimental knee pain reduce knee loading by reducing extension moment, whereas lateral wedges have the opposite effect and increase the extension moment.

The effect of shoe design and lateral wedges on knee load and neuromuscular control in healthy subjects during walking

The increasing number of patients with developing osteoarthritis is accompanied by a growing scientific interest in non-operative early treatment strategies. It is generally believed that laterally wedged insoles can change the distribution of knee loading. However, the importance of footwear design/type on the effectiveness of lateral wedging has not been investigated so far. The Purpose of the present study was to explore alterations in knee loading due to lateral foot wedges in three different shoes. Methods: Thirteen healthy participants with no history of knee pain were tested using three-dimensional gait analysis. Barefoot walking, walking in a running shoe, an Oxford-type leather shoe, and a rocker shoe were analysed. The shoes were tested both with and without a 10-degree full-length laterally wedged insole. Results: There were significant shoe*wedge interactions on the first and second peak knee adduction moments. However, the variability of this moment between shoe designs was of similar magnitude as the effect of laterally wedged insoles. Only marginal changes in muscle activity for gastrocnemius when walking with the wedged Oxford shoe were revealed. Conclusion: Lateral wedging is effective regardless of shoe design. Differences between the three neutral walking conditions underline the importance of footwear choice in individuals. It is safe to apply lateral wedges without jeopardising muscular control during walking regardless of shoe type. Possible effects of altering neuromuscular control by shoe type needs further exploration in patient groups.