METODOS SEGÚN LEY DEL IMPUESTO SOBRE LA RENTA (Art. 215, 216)

Abnormalities of the Plantar Soft Tissues

6.2 Plantar Heel Spur 179

6.3 Ledderhose Disease 181

6.4 Atrophy of the Plantar Fat Pad 183 6.5 Plantar Vein Thrombosis 184

6.6 Hallucis longus and Digitorum

longus Intersection Syndrome 186

6.7 Metatarsalgia 187

6.8 Plantar Warts 190

6.9 Compartment Syndrome of the

Interosseous Muscles 190

6 Abnormalities of the Plantar Soft Tissues

A. Roeser and U. Szeimies

6.1 Plantar Fasciitis, Rupture of the Plantar Fascia

Definition

Plantar fasciitis is caused by excessive loads at the origin of the plantar fascia on the calcaneal tuberosity. It is associated with inflammatory and degenerative changes in the plantar fascia and calcaneal fat pad. Partial tearing may occur with ad-vanced degenerative changes, and trauma to the fascia may cause partial or complete ruptures.

Symptoms

●Weight-bearing pain on the bottom of the heel

●Pain worse with initial steps in the morning

●Pain may radiate laterally around the posterior calcaneal tu-berosity due to irritation of the first branch of the lateral plantar nerve (Baxter nerve)

●Point of maximum tenderness is usually anteromedial to the main weight-bearing zone below the heel

●With rupture: plantar hematoma with tenderness

Predisposing Factors

●Overweight

●Repetitive strains (running, jumping, ball sports)

Anatomy and Pathology

The plantar fascia is a thick, multilayered aponeurosis that spans the sole of the foot in three directions and chiefly sup-ports the longitudinal arch with its five longitudinal slips that insert on the corresponding proximal phalanges. Transverse fi-bers give distal support to the longitudinal slips. Vertical fifi-bers extend around the short toe flexors, dividing the sole of the foot into three well-known compartments (large toe, small toe, and central compartment) while other fibers run through the fat pad to the skin. The loculation of the fat pad limits its mobility relative to the skin.

The plantar fascia originates from a broad area on the ante-rior and medial calcaneal tuberosity. Distally it splits into dig-ital slips that insert on the proximal phalanges of all the toes.

Imaging

Radiographs

●Lateral view of the calcaneus: bony plantar heel spur, possible intramuscular calcifications in the flexor digitorum brevis

●Weight-bearing views of the foot in three planes: to exclude hindfoot deformity

Ultrasound

●Longitudinal plantar ultrasound scan shows hypoechoic thickening of the plantar fascia (thickening to > 6 mm is defi-nitely pathologic).

●Plantar heel spur appears as an echogenic exostosis beneath the plantar fascia, and bursopathy appears as a hypoechoic zone.

●Progression to chronic stage is marked by increasing inhomo-geneous disintegration of the fascia, with partial tears causing loss of clear delineation. Involvement of the flexor digitorum brevis muscle bellies may be associated with hypoechoic hemorrhage and tearing of the perimysium.

MRI

Interpretation Checklist

●Extent of inflammation

●Accurate localization

●Describe longitudinal extent

●Involvement of fibro-osseous junction

●Fibro-osteitis

●Local zones of softening in the aponeurosis

●Risk of rupture

●Partial tearing

●Extent of inflammation in adjacent soft tissue of the heel

●Associated findings (other tendons in the hindfoot, degenera-tive joint changes, bone edema)

Examination Technique

Except in the case of a recent acute rupture, IV contrast admin-istration is recommended for better visualization of the acute and chronic inflammatory component with tendon vasculariza-tion, peritendinitis, and fibro-osteitis.

●Standard protocol: prone position, high-resolution multi-channel coil

●Sequences:

○Sagittal T1-weighted and PD-weighted fat-sat

○Axial T2-weighted and PD-weighted fat-sat

○Sagittal and coronal T1-weighted fat-sat after contrast ad-ministration

MRI Findings (▶Fig. 6.1,▶Fig. 6.2,▶Fig. 6.3)

●Edema and contrast uptake in the proximal plantar tendon, usually more pronounced on the medial side, with enhance-ment in the adjacent soft tissues of the heel

●Zones of mucoid degeneration within the tendon

●Partial tear appears hyperintense in the PD-weighted fat-saturated (fat-sat) sequence

●Degenerative tendon vascularity with increased enhancement

! Note

Even subtle findings may often cause significant complaints.

The extent of activation does not always correlate with the symptomatic picture.

Imaging Recommendation

Modality of choice: ultrasonography. MRI may be used as needed.

Differential Diagnosis

●Calcaneal stress fracture

●Tumors

●Infection

●Fat pad atrophy

●Fibromatosis of the plantar fascia

●Flexor hallucis longus tendinitis

●Compression of the tibial nerve or lateral plantar nerve (Baxter nerve)

●Radiculopathy at the S1 level

●Diseases with a chronic inflammatory or rheumatoid etiol-ogy: seronegative spondylarthropathy (human leukocyte antigen [HLA]-B27), psoriatic arthritis, reactive arthritis (titer assay); heel pain is usually bilateral

Treatment

Conservative

Conservative treatment is the preferred initial course of action for plantar fasciitis:

●Orthotic inserts that support or align the medial longitudinal arch while removing all weight from the fascial bundle

●Eccentric stretching exercises for the calf and plantar muscles (at-home program of exercises done 2 or 3 times daily)

●Nocturnal splints that position the ankle joint in dorsiflexion, especially recommended for pain during initial steps in the morning

●Oral NSAIDs / Cox-2 inhibitors

●Ultrasonic therapy, transverse friction massage

●Injection therapy (local anesthetics, steroids, platelet rich plasma [PRP], botulinum toxin)

●Local anesthetic, 2 to 3 x steroids, platelet-derived growth factor

●Orthovoltage therapy

●Shockwave therapy

●For acute rupture or partial tear: rest from sports participa-tion, ice, NSAIDs, orthotics, ultrasound

Operative

If all conservative options have been exhausted and have been unsuccessful for 6 months, surgical intervention is available as a last recourse:

●Surgical decompression and neurolysis of the first branch of the lateral plantar nerve (Baxter nerve; preoperative work-up includes neurologic tests, measurement of nerve conduction velocity)

●Half-thickness notching of the medial part of the plantar fascia at its origin with resection of the bony heel spur (the plantar fascia is not completely divided)

●Endoscopic plantar fascial release

Prognosis, Complications

Prognosis

The disease runs a self-limiting but protracted course in ap-proximately 80% of cases.

Surgical Complications

●Persistent pain

●Superficial or deep infection

●Scar pain

●Deep venous thrombosis

●Translocation of pain to the midfoot after complete division of the plantar fascia due to altered tension on the longitudinal arch

6.2 Plantar Heel Spur

Definition

A plantar heel spur is a bony excrescence on the inferomedial aspect of the calcaneal tuberosity.

Symptoms

The clinical presentation of heel pain is like that previously described for plantar fasciitis. The presence of a plantar heel spur does cause the heel pain; the underlying cause is the de-generative changes in the plantar fascia and fat pad that were described above. A fracture of the heel spur may cause the pain to intensify.

Predisposing Factors

See section 6.1 Plantar Fasciitis, Rupture of the Plantar Fascia (p. 178).

Fig. 6.1 Plantar fasciitis in a 39-year-old woman with increasing chronic heel pain. The patient had an occupation that required prolonged standing. Sagittal T1-weighted fat-sat image after contrast administration shows definite signs of activated insertional tendinop-athy of the plantar fascia (plantar fasciitis) with thickening of the plantar aponeurosis at the fibro-osseous junction, initial degenerative vascularization, and increased enhancement in the adjacent soft tissues, especially the fatty tissue of the heel.

Anatomy and Pathology

A heel spur is an intramuscular calcification in the flexor digitorum brevis located close to its origin on the plantar calcaneal tuberosity. The combined presence of a plantar and posterior heel spur may reflect a systemic insertional tendinopathy.

Imaging

Radiographs (▶Fig. 6.4)

●The spur usually points forward, reflecting an adaptation to unphysiologic pressure loads.

●Bony plantar spur may be on the calcaneus or broken from it.

●Stress radiographs of the foot are obtained in three planes to exclude a hindfoot deformity.

Ultrasound

Longitudinal plantar scan shows a protrusion on the echogenic bony undersurface of the calcaneus beneath the plantar fascia, pointing away from the surface. Hypoechoic bursopathy may be evident between the spur and fascia.

MRI

Interpretation Checklist

●Assessment of the activation of the heel spur

●Extent of bone marrow edema

●Involvement of the plantar tendon

●Inflammation in the soft tissues of the heel

Examination Technique

●Standard protocol: prone position, high-resolution multi-channel coil

Fig. 6.2 a–c Plantar fasciitis.

a Coronal T2-weighted image shows marked thickening of the plantar aponeurosis on the me-dial side.

b T1-weighted fat-sat image after contrast ad-ministration shows intense enhancement within the tendon and in adjacent soft tissues including the muscles and calcaneal fat pad.

c Sagittal T1-weighted fat-sat image after con-trast administration shows definite features of plantar fasciitis with intratendinous enhancement at the fibro-osseous junction.

●Sequences:

○Sagittal T1-weighted and PD-weighted fat-sat

○Axial T2-weighted and PD-weighted fat-sat

○Sagittal and coronal T1-weighted fat-sat after contrast administration

MRI Findings

●Heel spur is clearly visible in the T1-weighted sagittal se-quence

●Possible activation of the spur with bone-marrow edema and contrast enhancement at the fibro-osseous junction

●Edema in the plantar fat pad below the heel spur

Imaging Recommendation

Modalities of choice: radiography; contrast-enhanced MRI to assess activation of the heel spur and the integrity of the plan-tar aponeurosis.

Differential Diagnosis

●Plantar fasciitis

●Bursopathy

●Calcaneal stress fracture

●Tumor

●Infection

●Compression of the tibial nerve or lateral plantar nerve (Baxter nerve)

●S1 radiculopathy

●Diseases with a chronic inflammatory or rheumatoid etiol-ogy: seronegative spondylarthropathy (HLA-B27), psoriatic arthritis, reactive arthritis (titer assay); heel pain is usually bilateral

●Plantar vein thrombosis

Treatment

Conservative

! Note

When planning treatment, note that a plantar heel spur is usu-ally the result of plantar fasciitis; it rarely occurs as a separate entity.

The initial course of action for a plantar heel spur is conserva-tive treatment. Shockwave therapy is becoming increasingly important.

Operative

An acutely fractured heel spur can be managed by removing the spur and notching the plantar fascia, but only after conservative options have been tried.

Prognosis, Complications

See section 6.1 Plantar Fasciitis, Rupture of the Plantar Fascia (p. 178).

6.3 Ledderhose Disease

Definition

Ledderhose disease is defined as the presence of benign, firm, fibrous nodules in the sole of the foot, often located along the medial border of the plantar fascia.

Symptoms

●Complaints relating to footwear pressure on the nodules

●Load-dependent pain in the sole of the foot Fig. 6.3 A 55-year-old man with acute stabbing pain due to a

complete rupture of the plantar fascia. The patient gave no history of trauma. Sagittal PD-weighted fat-sat image shows a complete rupture of the plantar fascia near its insertion with slight retraction of the tendon end.

Fig. 6.4 Plantar heel spur. Lateral radiograph of the calcaneus.

Predisposing Factors

●Etiology unclear

●Males predominantly affected

●Correlation with Dupuytren disease

●Association with diabetes mellitus

●Increased alcohol consumption has been cited as a predisposing factor

Anatomy and Pathology (▶ Fig. 6.5)

The medial border of the plantar fascia is most commonly af-fected. Formation of the nodules proceeds in various phases (proliferative, maturation phase). Well-differentiated fibroblasts develop which invade the deep soft-tissue structures of the plantar fascia or superficially infiltrate the skin. The slight con-tractile activity of the myofibroblasts leads to shortening and contracture of the plantar fascia.

Imaging

Radiographs

Radiographs do not advance the diagnosis of the soft-tissue masses. Weight-bearing radiographs can be taken after surgical removal of the plantar fascia to evaluate the secondary change in the medial longitudinal arch.

Ultrasound

Longitudinal and transverse plantar scans demonstrate individ-ual or multiple, superficial, hypoechoic nodules in the plantar fascia.

MRI

Interpretation Checklist

●Confirm the presumptive diagnosis

●Preoperative planning

●Note number, size, and exact location of the nodules

●Assess the integrity of the plantar fascia

Examination Technique

●Standard protocol: prone position, high-resolution multi-channel coil

●Sequences:

●Sagittal T1-weighted and PD-weighted fat-sat

●Axial T2-weighted and PD-weighted fat-sat

●Sagittal and axial T1-weighted fat-sat after contrast administration

MRI Findings (▶Fig. 6.6)

The single or multiple nodular thickenings along the middle third of the plantar fascia are usually difficult to identify be-cause their high cellularity and very low water content be-cause them to appear isointense in most sequences. They have scant vascularity and are often poorly visualized after contrast ad-ministration. They are most clearly depicted in the PD-weighted fat-sat sequence and unenhanced T2-weighted sequence.

The plantar fascia should be fully surveyed over its entire length. If necessary, a skin marker capsule can be placed to identify the area of maximum localized pain.

! Note

Even tiny nodules with an unimpressive MRI appearance may be very painful and should be identified

Imaging Recommendation Modality of choice: MRI.

Differential Diagnosis

Fibrosarcoma.

Fig. 6.5 a–c Plantar fibromatosis affecting the medial middle third of the plantar fascia.

a Clinical appearance.

b MRI appearance.

c Surgically resected area of plantar fibromatosis.

Treatment

Conservative

●Orthotic shoe inserts that relieve pressure on the nodules

●NSAIDs

Operative

●Complete or partial resection of the plantar fascia in patients with increasing pressure-related complaints after an unsuc-cessful trial of shoe inserts

●Prophylactic surgical removal is not indicated

Prognosis, Complications

Possible complications are as follows:

●High recurrence rate after local removal of nodules

●Scar pain

●Plantar nerve injury with dys- or hypoesthesia, neuroma formation

6.4 Atrophy of the Plantar Fat Pad

Definition

Degenerative changes in the plantar calcaneal fat pad or the fat pad at the level of the metatarsal heads can decrease the resil-ience and water content of the fat pad, compromising its func-tion as a shock absorber.

Symptoms

●Load-dependent heel pain or metatarsalgia

●Secondary deformity of the small toe

Predisposing Factors

●Splayfoot deformity

●Pes planovalgus

●Overweight

●Diabetes mellitus

Anatomy and Pathology

Anatomy

The plantar fat pad has an important role in cushioning the im-pact forces on the heel during walking. The fat pad can cushion and diffuse the massive heel-strike forces by virtue of its ana-tomic design: a honeycomb arrangement of fibroelastic fibers with septa anchored to both skin and bone arranged in a U-shaped pattern around the calcaneal tuberosity.

Pathology (▶Fig. 6.7)

Degenerative changes in the fat pad, characterized by a loss of resilience and water content, compromise its shock-absorbing function and increase the loads on the calcaneal tuberosity. In addition, degenerative changes in the distal portion of the plan-tar aponeurosis near its insertion may lead to changes in the fat pad and plantar plate at the level of the metatarsal heads.

Secondary degenerative changes in the metatarsophalangeal joints with associated secondary deformities of the small toe may result.

Imaging

Radiographs

Weight-bearing radiographs of the foot in three planes:

●Evaluation of the longitudinal arch

●Presence of splayfoot deformity

●Metatarsal alignment

●Exclude a deformity of the small toe

Ultrasound

Longitudinal and transverse plantar scans show thinning of the echogenic plantar fat pad.

MRI

Fat pad atrophy is usually a clinical diagnosis and there is no need for MRI. But MRI can be used to narrow the differential Fig. 6.6 a, b Ledderhose disease (plantar fibromatosis) in a patient with painful nodular thickening below the pedal arch along the plantar tendon.

a Sagittal T1-weighted image shows fusiform nodular thickening within the plantar tendon (arrow).

b Sagittal T1-weighted fat-sat image after contrast administration shows somewhat unusual enhancement of the very cellular fibrotic nodule in Led-derhose disease. Ordinarily the nodular thickenings show little or no increased enhancement (arrow).

diagnosis (plantar fasciitis, activated heel spur, bone overload, or fatigue fracture of the calcaneus).

Interpretation Checklist

●Evaluate the plantar fat pad

●Determine extent of edema and contrast enhancement

●Determine extent of fibrosis and chronicity of the inflamma-tory condition

●Detect or exclude bone marrow edema in the calcaneus

Examination Technique

●Standard protocol: prone position, high-resolution multi-channel coil

●Sequences:

○Sagittal T1-weighted and PD-weighted fat-sat

○Axial T2-weighted and PD-weighted fat-sat

○Sagittal and coronal T1-weighted fat-sat after contrast ad-ministration

MRI Findings

●Patchy, sometimes irregular areas of edema in a visibly thinned plantar fat pad

●Unenhanced T1-weighted sequence may show hypointense fibrotic areas in chronic cases

●Thickening of the skin

Imaging Recommendation

Most cases are diagnosed clinically, but MRI is useful for inter-preting equivocal symptoms and excluding other possible diag-noses.

Differential Diagnosis

●Plantar fasciitis

●Stress fractures of the calcaneus or metatarsals

●Morton neuroma

●Peripheral polyneuropathy

●Tarsal tunnel syndrome with atrophy of the intrinsic muscles

●Chronic inflammatory joint disease

Treatment

Conservative

Orthotic inserts that relieve pressure on the metatarsal heads and cushion the heel.

Operative

●Lengthening the Achilles tendon in patients with splayfoot deformity

●With massive fat pad atrophy at the level of the metatar-sal heads with pronounced metatarmetatar-salgia and plantar prominence of the metatarsal heads: an elevating distal osteotomy of the metatarsals or condylectomy may be performed

●Cushioning shoe inserts are usually essential after surgery

Prognosis, Complications

Prognosis

The disease runs a chronic course and is generally managed by shoe inserts and surgical treatment.

Possible Complications

●Persistence of metatarsalgia

●Limited motion in the operated metatarsophalangeal joints

●Development of secondary toe deformities

●Formation of plantar ulcers in patients with coexisting polyneuropathy

In document Residentes en el extranjero (página 154-165)