Stainsby GD. Pathological anatomy and dynamic effect of the displaced plantar plate and the importance of the integrity of the plantar plate-deep transverse metatarsal ligament tie-bar

Royal Victoria Infirmary, Newcastle upon Tyne.
Annals of The Royal College of Surgeons of England (Impact Factor: 1.27). 02/1997; 79(1):58-68.
Source: PubMed


Normal and deformed forefeet have been investigated by cadaver anatomical dissections and experiments, by radiographs, CT and MRI scanning, and by clinical studies. Evidence is presented to show that the skeleton of the foot rests on and is controlled by a multi-segmental ligamentous and fascial tie-bar system. Transversely across the plantar aspect of the forefoot, the plantar plates and the deep transverse metatarsal ligaments form a strong ligamentous structure which prevents undue splaying of the forefoot. Longitudinally, the five digital processes of the deeper layer of the plantar fascia are inserted into the plantar plates and control the longitudinal arch of the foot. It is suggested that many forefoot deformities result from the failure of parts of the tie-bar system and the dynamic effect of displacement of the plantar plates. Understanding this allows a more logical approach to their treatment.

Download full-text


Available from: Gearge David Stainsby, Sep 05, 2015
  • Source
    • "During gait, the windlass mechanism acts in two ways; (1) it helps to maintain the shape of the MLA when the foot has to manage downward forces at stance (reversed windlass mechanism) and (2) it causes a rise of the MLA and shortening of the foot at late stance, as the plantar fascia tightens at toe off due to dorsiflexion of the MTP joints [2]. The windlass mechanism provides information regarding the biomechanical function of the foot [3] [4]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Based on the windlass mechanism theory of Hicks, the medial longitudinal arch (MLA) flattens during weight bearing. Simultaneously, foot lengthening is expected. However, changes in foot length during gait and the influence of walking speed has not been investigated yet. The foot length and MLA angle of 34 healthy subjects (18 males, 16 females) at 3 velocities (preferred, low (preferred -0.4m/s) and fast (preferred +0.4m/s) speed were investigated with a 3D motion analysis system (VICON(®)). The MLA angle was calculated as the angle between the second metatarsal head, the navicular tuberculum and the heel in the local sagittal plane. Foot length was calculated as the distance between the marker at the heel and the 2nd metatarsal head. A General Linear Model for repeated measures was used to indicate significant differences in MLA angle and foot length between different walking speeds. The foot lengthened during the weight acceptance phase of gait and shortened during propulsion. With increased walking speed, the foot elongated less after heel strike and shortened more during push off. The MLA angle and foot length curve were similar, except between 50% and 80% of the stance phase in which the MLA increases whereas the foot length showed a slight decrease. Foot length seems to represent the Hicks mechanism in the foot and the ability of the foot to bear weight. At higher speeds, the foot becomes relatively stiffer, presumably to act as a lever arm to provide extra propulsion.
    Full-text · Article · Oct 2013 · Gait & posture
  • Source
    • "Cadaveric studies of the feet in RA have suggested that forefoot deformities in RA might result from failure of the complex ligamentous system and the dynamic effect of displacement of the plantar plates [4]. However, the structures involved, the potential mechanisms by which changes occur and the relationship between synovial, bone and plantar plate abnormalities have not been clearly identified in patients with RA. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Previous cadaveric studies have suggested that forefoot deformities at the metatarsophalangeal (MTP) joints in patients with rheumatoid arthritis (RA) might result from the failure of the ligamentous system and displacement of the plantar plates. This study aimed to examine the relationship between plantar plate pathology and the rheumatoid arthritis magnetic resonance imaging score (RAMRIS) of the lesser (second to fifth) MTP joints in patients with RA using high-resolution 3 T magnetic resonance imaging (MRI). In 24 patients with RA, the forefoot was imaged using 3 T MRI. Proton density fat-suppressed, T2-weighted fat-suppressed and T1-weighted post gadolinium sequences were acquired through 96 lesser MTP joints. Images were scored for synovitis, bone marrow oedema and bone erosion using the RAMRIS system and the plantar plates were assessed for pathology. Seventeen females and 7 males with a mean age of 55.5 years (range 37-71) and disease duration of 10.6 years (range 0.6-36) took part in the study. Plantar plate pathology was most frequently demonstrated on MRI at the fifth MTP joint. An association was demonstrated between plantar plate pathology and RAMRIS-reported synovitis, bone marrow oedema and bone erosion at the fourth and fifth MTP joints. In patients with RA, 3 T MRI demonstrates that plantar plate pathology at the lesser MTP joints is associated with features of disease severity. Plantar plate pathology is more common at the fourth and fifth MTP joints in subjects with RA in contrast to the predilection for the second MTP reported previously in subjects without RA.
    Full-text · Article · Dec 2011 · Clinical Rheumatology
  • [Show abstract] [Hide abstract]
    ABSTRACT: In the severely clawed lesser toe, the plantar plate of the metatarso-phalangeal joint becomes displaced onto the dorsal aspect of the metatarsal head and causes it to be depressed. The results of a surgical procedure replacing the plantar plate to its correct position are presented.Thirty feet in 23 patients have been reviewed. Preoperatively, all patients had metatarsalgia as a result of severely clawed lesser toes. The average age was 60 years (26–84 years) and the average follow-up period was 23 months (6–62 months).In 18 feet (56 toes), the deformities were due to rheumatoid arthritis. Eight feet (10 toes) had lesser toe deformities secondary to hallux valgus, and in three feet (3 toes) there was no obvious cause. One patient had severe clawing of two toes as a result of long-standing missed traumatic dislocations of the metatarso-phalangeal joints.In the rheumatoid group, 12 feet (67%) were rated as excellent, four feet (22%) were good, one (5.5%) fair and one (5.55%) had poor results. In the non-rheumatoid feet, six (49.9%) wererated as excellent, five (41.6%) were rated as good, and one (8.3%) had a fair result.
    No preview · Article · Sep 2001 · The Foot
Show more