METAL HEMI Great Toe Implant SURGICAL TECHNIQUE
Contents Chapter 1 4 Product Information 4 Device Description Chapter 2 5 Intended Use 5 Indications 5 Contraindications Chapter 3 6 Surgical Technique 10 Postoperative Protocol 10 Explant Information Appendix 11 Ordering Information Wright recognizes that proper surgical procedures and techniques are the responsibility of the medical professional. The following guidelines are furnished for information purposes only. Each surgeon must evaluate the appropriateness of the procedures based on his or her personal medical training, experience, and patient condition. Prior to use of the system, the surgeon should refer to the product Instructions For Use package insert (152206) for additional warnings, precautions, indications, contraindications and adverse effects. Instructions For Use package inserts are also available by contacting the manufacturer. Contact information can be found on the back of this surgical technique and the Instructions For Use package inserts are available on wmt.com under the link for Prescribing Information. Please contact your local Wright representative for product availability.
Product Information chapter 1 Device Description The Metal Hemi Implant consists of one component to replace the articulation of the proximal phalanx of the first metatarsophalangeal joint, and corresponding instrumentation to facilitate insertion. The Metal Hemi Implant is fixed by means of a stem, which is inserted into the medullary canal of the phalanx. The profile of the metal base plate articulates with the metatarsal head. Instrumentation is provided to assist in the surgical implantation of this great toe system. It is important that instruments and trial implants used are those specifically designed for this device to ensure accurate installation. The base of the stem and under side of the body is plasma sprayed with commercially pure titanium. B A D E F Metal Hemi Implant Dimensions C Description A B C D E F Small Metal Hemi Implant 17 2.3 10.8 7.6 12.9 2.8 Medium Metal Hemi Implant 20 2.4 10.8 7.6 15.2 2.8 Large Metal Hemi Implant 21.5 2.5 10.8 7.6 16.4 2.8 Extra Large Metal Hemi Implant 23 2.5 10.8 7.6 17.5 2.8 *ALL SIZES SHOWN ARE IN MILLIMETERS 4 Chapter 1 Product Information
Intended Use chapter 2 Indications The Metal Hemi Implant is designed to supplement first metatarsal phalangeal joint arthroplasty. Indications include hallux limitus or hallux rigidus, painful hallux valgus, revision of failed previous surgery and painful arthritis. Contraindications Contraindications for the use of the Metal Hemi Implant include any condition, which would contraindicate the use of the replacement in general, including: Poor bone quality, which may affect the stability of the implant Severe tendon, neurological, or vascular deficiencies, which would compromise the affected extremity Any concomitant disease, which may compromise the function of the implant Active infection Rheumatoid arthritis Prior to use of the system, the surgeon should refer to the product instructions for use package insert for warnings, precautions, indications, contraindications and adverse effects. Instructions for use package inserts are also available by contacting the manufacturer. Contact information can be found on the back of this surgical technique and the instructions for use package inserts are available on wmt.com under the link for Prescribing Information. Chapter 2 Intended Use 5
Surgical Technique chapter 3 The 1st MPJ is exposed through a standard bunion incision dorsal medially. The longitudinal capsulotomy is performed with care to maintain the insertion of the flexor brevis tendon attachment at the base of the proximal phalanx. The flexor halluces brevis insertion extends distal along the plantar aspect of the proximal phalanx thus allowing careful resection of the articular surface while maintaining flexion stability of the great toe. FIGURE 1 FIGURE 1 Resection of the articular surface of the base of the proximal phalanx is performed with a sagital saw. A sufficient amount of bone to allow placement of the implant can be performed free hand or with available cutting guides. FIGURE 2 NOTE: The Metal Hemi Instrument Tray comes with two different cutting guides: Use of the standard cutting guide will remove 2mm and use of the decompression cutting guide will remove 4mm. FIGURE 2 6 Chapter 3 Surgical Technique
Modeling of the metatarsal head is performed by resecting the osteophytes that may be present. Subchondral drilling of the metatarsal head and release of the sesmoids should be performed if necessary to gain joint motion. The size of the implant is determined by using the sizers. The implant should be flush with the cortex and not overlap margins of the remaining base of the phalanx. Implants are available in small, medium, large, and extra large. FIGURE 3 FIGURE 3 The template allows the medullary canal to be marked through a hole that is dorsally eccentric for placement of the implant. Access of the canal is created with a starting awl. FIGURE 4 FIGURE 4 Chapter 3 Surgical Technique 7
Trial implants have been designed with pin holes at the dorsal margins that allow grasping with bone forceps for better handling while sizing the implant. FIGURE 5 FIGURE 5 The joint is put through a range of motion to check for sufficient joint dorsiflexion. Modest manual traction of the toe should demonstrate separation of the joint with minimal tension. Insufficient joint decompression can result in continued hallux limitus postoperatively. FIGURE 6 NOTE: Additional joint motion and decompression can be obtained by remodeling the metatarsal head and further resection of the proximal phalanx as necessary. FIGURE 6 8 Chapter 3 Surgical Technique
The cruciate punch instrument is then used to open the medullary canal to accept the stem of the implant. Once the joint has been prepared and correct size determined, the implant is fitted into place. FIGURE 7 FIGURE 7 The implant impactor is used to place the stem in the medullary canal until the implant base is seated against the cortex of the proximal phalanx. FIGURE 8 FIGURE 8 Chapter 3 Surgical Technique 9
The joint is reduced and evaluated for range of motion. Proper fit should be documented radiographically. FIGURE 9 FIGURE 9 Postoperative Protocol Shoe gear weight bearing as tolerated. Progression to regular shoe gear and activities is allowed as per patient s reduction in discomfort and swelling. Postoperative care is the responsibility of the medical professional. Explant Information If the removal of the implant is required due to revision or failure of the device, the surgeon should contact the manufacturer using the contact information located on the back cover of this surgical technique to receive instructions for returning the explanted device to the manufacturer for investigation. 10 Chapter 3 Surgical Technique
Headline Ordering Headline Information Appendix Metal Hemi Implant System MHMIKIT1/A 1 3 4 5 7 2 6 8 Implants Sterile-Packed Instruments PN Description 03-6000-16 Small Implant 03-6000-17 Medium Implant 03-6000-18 Large Implant 03-6000-19 Extra-Large Implant PN Description 1. 03-6000-14 Cut Guide 2. 03-6000-15 Decompression Cut Guide 3. 03-6000-05 Small/Medium Sizer 4. 03-6000-06 Large/Extra Large Sizer 5. 03-6000-13 Starter Awl 6. 03-6000-07 Small Hemi Trial 03-6000-08 Medium Hemi Trial 03-6000-09 Large Hemi Trial 03-6000-10 Extra Large Hemi Trial 7. 03-6000-11 Cruciate Punch 8. 03-6000-12 Implant Impactor Appendix Ordering Information 11
Wright Medical Technology, Inc. 1023 Cherry Road Memphis, TN 38117 800 238 7117 901 867 9971 www.wmt.com Wright Medical EMEA Atlas Arena, Australia Building Hoogoorddreef 7 1101 BA Amsterdam the Netherlands 011 31 20 565 9060 Wright Medical UK Ltd. Unit 1, Campus Five Letchworth Garden City Hertfordshire SG6 2JF United Kingdom 011 44 (0)845 833 4435 Trademarks and Registered marks of Wright Medical Technology, Inc. 2014 Wright Medical Technology, Inc. All Rights Reserved. 011260A 10-Nov-2014