Implants



Implants





IMPLANTS

The most common pathogen to cause infection during implant surgery is Staphylococcus epidermis. Vancomycin is the drug of choice for antibiotic prophylaxis during implant surgery. Most metal joint implants are made of cobalt-chromium due to its high strength and smooth-polished finish. The smooth-polished finish is less destructive on cartilage. These same implants may have stems and undersurfaces that are coated with titanium plasma spray to encourage osseous integration.


FIRST METATARSOPHALANGEAL JOINT IMPLANTS


Hemi Implants

Hemi implants are indicated for hallux limitus and hallux rigidus in the first ray and advanced arthritis in the lesser MPJs. They are used to replace the base of the proximal phalanx. On the first ray, minimal bone resection is important to preserve the insertion of the flexor halluces brevis tendon. These implants require an adequate articular surface on the metatarsal head.


AnaToemic Hemi-Prosthesis










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Made of cobalt-chromium with grit-blasted phalangeal surface and stem

Arthrex



Vilex Cannulated Hemi Implant










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Cobalt-chrome

Cannulated

Implant screws into the bone

Cannot be used at the same joint with the Vilex Cannulated Hemi Implant


Wright Hemi Phalangeal Implant (HPI)










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Cobalt-chromium

Trapezoidal shape matches the shape of the phalanx.

Recessed central plantar area to avoid irritation of the flexor tendons

Partial, plasma-sprayed, titanium stem and undersurface coating for osseous integration

Includes optional suture holes for flexor tendon attachment


BioPro First MPJ Hemi Implant










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Cobalt-chromium

Available in porous and nonporous-coated stems


BioPro Lesser MPJ Hemi Implant










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Cobalt-chromium

Indicated for the lesser MPJs

Different stem design to accommodate the smaller phalanges

Available in a cannulated version


OsteoMed Hemi Great Toe Implant










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Cobalt-chromium


Plantar surface of the implant is flat to avoid irritation of the flexor tendons.


Metal Hemi Toe (MHT)










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Cobalt-chromium with a titanium plasma-sprayed stem

Trapezoidal articular surface and stem better match the geometry of the proximal phalanx.

Fifteen-degree angle between the articular surface and the stem in the sagittal plane to accommodate for the metatarsal declination angle

Stem becomes thicker going from the tip toward the base to better conform to the shape of the medullary canal of the proximal phalanx.

Integra LifeSciences Corp.


LPT 2 (Low Profile Toe) Great Toe Implant










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Titanium

Available in straight or angled options for increased PASA

Angled option comes in two sizes: size 1 is 18° and size 2 is 16°.

Only difference between the LPT and the LPT 2 is the instrumentation.

Cruciate stem

Two perforating holes to secure FHB, angled version has a third hole, placed medially to prevent lateral subluxation

Wright Medical Technology Inc.


K2 Hemi Implant










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Cobalt-chromium with titanium plasma-coated stem

Perforating hole plantarly to secure FHL to the base of the phalanx and implant, preventing a hallux hammertoe

Integra LifeSciences Corp.


3S Hemi Toe










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Cobalt-chromium


Low profile head with plantar surface of the implant is flat to avoid irritation of the flexor tendons.

Tri-spade stem

Trilliant


Metatarsal Resurfacing Implants (Metatarsal Hemi Implants)


Metatarsal Decompression Implant (MDI)










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Cobalt-chromium with plasma-sprayed titanium coating on stem

Head is angled to avoid interference with the weight-bearing surface and provide progressive decompression through dorsiflexory ROM.

Wright Medical Technology Inc.


Lesser Metatarsal Head Implant (LMH)

Same as MDI but made for lesser metatarsals

Wright Medical Technology Inc.


Arthrosurface HemiCAP Toe Implant










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Consists of two components, a cap (cobalt-chrome) and a screw in stem (titanium), that fit together


EnCompass Metatarsal Resurfacing Implant










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Cobalt-chromium with titanium plasma- and hydroxyapatite-coated undersurface

Osteomed


Vilex Cannulated Metatarsal head Implant










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Cobalt-chromium

Cannulated

Implant screws into the bone

Cannot be used in the same joint with the Vilex Cannulated Metatarsal Head Implant


Total One Piece Hinged Implants


Swanson Flexible Toe Implant










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Silicone

Two stem sizes, standard and small


Midsection of the implant is U-shaped; opening of “U” can be directed dorsally or plantarly.

The two stems are in the same plane and perpendicular to the hinge.

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Nov 20, 2018 | Posted by in ORTHOPEDIC | Comments Off on Implants

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