Published on the Jan. 20, 2016, Rheumatology Network website
By Whitney L.J. Howell
According to a new study, prefabricated foot orthoses and rocker sole footwear can effectively reduce peak pressure under the first metatarsophalangeal joint (MTPJ) associated with osteoarthritis. However, they relieve pressure differently.
The study assessed how prefabricated foot orthoses and rocker sole footwear affected spatiotemporal parameters, hip and knee kinematics, and plantar pressures in first MTPJ OA patients. Findings were published in the Dec. 7, 2015, issue of Arthritis Care & Research.
Researchers studied 88 spatiotemporal/kinematic and 87 plantar pressure participants. Patients had first MTPJ pain for at least 12 weeks, pain rated at least 20 mm on a 100 mm visual analogue scale, less than 64 degrees of first MTPJ dosiflexion range of motion, and pain upon first MTPJ dorsal aspect palpation. They walked household distances without walkers, crutches, or canes, avoided other interventions, stopped all pain medications, and submitted to two X-rays.
Researchers tested two interventions. A prefabricated foot orthoses group received full-length orthoses with cut-out sections beneath the first metatarsal and trimmed distal edges to the second and fifth toe sulci level. Participants with pronated feet received wedges to reduce their Foot Pressure Index scores. The rocker sole footwear group received appropriately-sized rocker sole shoes with rounded soles in an anteroposterior direction and a soft-cushioned heel.
During gait analysis, the prefabricated group wore their own shoes with and without orthoses, and the rocker sole group compared their regular shoes to rocker sole shoes. All participants walked 250 m and completed four, 8 m walking trials. Researchers recorded hip and knee joint range of motion with wireless, wearable sensors. The in-shoe Pedar system measured peak plantar pressure under the hallux, lesser toes, first MTPJ, second to fifth MTPJs, mid-foot and heel.
Orthoses increased lesser toes and midfoot peak pressure, as well as decreased first MTPJ pressure. Rocker sole shoes decreased peak pressure under the first MTPJ, second to fifth MTPJs, and heel. Findings suggested lesser toes, second to fifth MTPJs and mid-foot peak pressure were lower in rocker soles, but no difference existed in first MTPJ peak pressure.
Researchers found prefabricated orthoses redistributed loads away from the first MTPJ, likely by shifting it to the medial longitudinal arch during mid-stance and the lesser toes during propulsion. Rocker sole shoes reduced cadence and slowed velocity, producing a cautious gait and reducing sagittal plane hip motion. It also alleviates forefoot peak pressure (reducing pain), indicating rocker sole shoes could therapeutically benefit people with symptomatic first MTPJ osteoarthritis.
The study was limited, researchers said, because they couldn’t blind participants to intervention assignment, and observed changes are immediate effects only. Gait analysis also didn’t allow for in-shoe MTPJ kinematics assessment, and the wearable sensor motion analysis system is restricted to knee and hip sagittal plane evaluation.
To read the article at its original location: http://www.rheumatologynetwork.com/osteoarthritis/shoes-relieve-osteoarthritis-foot-pain
