Efficacy Innovation ABG II. Brochure. Surgical Protocol. Cemented Stem

Transcription

1 Efficacy Innovation ABG II Cemented Stem Brochure Surgical Protocol

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3 The ABG Hip System The ABG hip implant range has been progressively extended and enhanced over the past years, harnessing extensive clinical experience and advances in technology. A world-leading Total Hip Replacement System, the ABG Hip System, comprises: The cementless ABG and ABGII Hydroxyapatite-coated Stems The cementless ABGII Acetabular Cup Range The cemented ABG and ABGII Vitallium Stems Restoration DLS ABG Revision Stem The ABGII Cemented Vitallium prosthesis is an integral part of the total ABG Hip System, offering the same proven anatomic design and common instrumentation for intra-operative flexibility. The ABGII cemented stem has been designed in close collaboration with leading international orthopaedic surgeons and bioengineers to ensure reliability and longterm functionality. ABGII Cemented Vitallium Stem with ABGII HA-Coated Acetabular Cup ABGII No-Hole Cup, 5-Hole Cup and Duration Stabilised Polyethylene Insert 3

4 The ABG II Cemented Femoral Stem The ABG II Hip System allows the surgeon to choose between a cemented or a cementless ABG implant, to suit the individual patient s needs and to cater for conditions such as poor bone stock. The actual choice may be made during surgery, since the same instrumentation is used for implantation of the cemented and the cementless stem. Optimised for cemented procedures, the ABGII Cemented Vitallium stem design provides the following advantages in clinical use: Anatomic Stem Excellent primary stability is achieved through the ABG stem shape. The anatomic shape results in proximal load transfer. This ensures normal stress distribution, maintaining healthy bone in the proximal femur. Forged Vitallium Alloy The proprietary Stryker cobalt chrome alloy provides: Proven compatibility with cemented applications High strength for loading Better resistance to abrasion Durability Conical, Distally Flattened Stem Reduced metal volume, compared with the cementless stem; fits inside the broach profile Allows easier insertion into the cement mantle, and compresses the cement May be used with a distal stem PMMA centraliser to ensure correct positioning Flared Metaphyseal Portion Preserves the anatomical features of the cementless stem Helps the implant to sit correctly in the metaphysis Reduced metal volume leaves vital space for the cement mantle Proximal Vertical Grooves The grooves allow for smooth cement flow, and increase the total metaphyseal surface area of the implant. Proximal stem with vertical grooves Distal stem with centraliser Flared metaphyseal geometry of stem 4

5 The ABG II Cemented Femoral Stem Elliptical Cross-Section The non-cylindrical shape assists stability by preventing rotation of the stem. Satin Finish The satin surface minimises micromotion of the stem and maintains the mechanical engagement of the stem in the cement mantle. Range of ABG II Cemented Stems There are six anatomical stem sizes, in left and right versions. The stems may be used with two different cementing techniques: ABGII Cemented Stem Size (Left & Right) Stem Length (mm) Distal Diameter (mm) Thin-layer cement mantle (Self-Locking Mantle) Thicker, continuous, all-round cement mantle (Full Mantle) By selecting the appropriate stem and broach combination, self-locking or the full cement mantle can be used. either the ABG II Cemented Stem Self-Locking Mantle Stem size same as Broach size ABG II Cemented Stem Full Cement Mantle Stem size smaller than Broach size 5

6 Pre-Operative Planning The surgical protocol for implanting the ABG II Cemented Vitallium stem is exactly the same as that used for the cementless stem, up to the implant size selection stage. A space has to be created to accommodate the implant and its cement mantle, with interdigitation of the cement into the cancellous bone. Pre-Operative Planning Templating is an essential step in the procedure and will assist with: Selection of final broach size The femoral neck resection level Control of limb length, by indicating the required femoral head neck length Pre-operative planning is done with stem templates with a magnification factor of 1.. The templates are laid over A-P femoral radiographs which have the same factor (Fig. 1 & 2). The proximal shoulder of the stem (D) should be at the level of the digital fossa (d). The inferolateral part (E) (the "elbow" of the prosthesis) is supported against the inferolateral border of the greater trochanter (e), preserving the cancellous bone near the cortex. Once metaphyseal fill has been established, the diaphyseal pattern is checked to see whether reaming will be necessary. Reaming will only be needed in very rare cases. The femoral neck osteotomy is defined by the upper points C (neck point) and D (digital point) shown on the templates; the level is provided by the distance measured from the most proximal point of the head or of the lesser trochanter (st). X-ray templates are available for the ABGII Acetabular Cup. Pre-operative planning of the cup establishes the centre of rotation of the implant; this must come as close as possible to the normal anatomical geometry. The neck length may be varied to reach the desired dimensions. However, following acetabular reaming at surgery the templated cup size may need modifying. It should be noted that pre-operative planning is done exclusively on A-P view films, since lateral films are not reliable enough for use in templating. The final implant size will be chosen intraoperatively, as the conditions encountered during surgery may require a size other than the templated size. e d st c t d D e E 3 C st c T t Ø8.5mm Fig. 1 X-ray with landmarks Fig. 2 X-ray with template showing landmarks 6

7 Pre-Operative Planning Cement Mantle & Stem/Broach Selection Self Locking Cement Mantle Surgeons who wish to use thin-layer cementing (self-locking of the stem) should choose an implant of the same size as that of the final broach. Please note that a thin cement mantle option is not possible if a size 8 broach is selected, as a size 8 stem is not available. Full Cement Mantle Surgeons who wish to use a thicker cement mantle should select an implant one size smaller than the final broach size. Please note that a full cement mantle option is not possible if a size 2 broach is selected, as a size 1 stem is not available. ABG II Cemented Range Self-Locking Mantle Broaches SELF-LOCKING CEMENT MANTLE Stems Ø.1mm Ø8.5mm Self-Locking Mantle Stem Size Same as Broach Size RIGHT RIGHT Fig. 3 Broach and stem selection for self-locking mantle Fig. 4 ABGll Cemented Stem template for self-locking cement mantle ABG II Cemented Range Full Cement Mantle Broaches FULL CEMENT MANTLE Stems Ø.1mm Ø8.5mm Full Cement Mantle Stem Size Smaller than Broach Size RIGHT RIGHT Fig. 5 Broach and stem selection for full cement mantle Fig. 6 ABGll Cemented Stem template for full cement mantle

8 Surgical Protocol Overview of Surgical Protocol The Surgical Protocol for the insertion of the ABG II Cemented Vitallium Stem involves the following steps:- Neck resection Cup insertion Opening of the proximal femur Flexible reaming of the femur, if necessary Preparation of metaphyseal implant bed with broach/trials Trial reduction Cementing and insertion of definitive implant Final reduction Post-operative management Patient Positioning The hip may be accessed via most of the conventional approaches. The technique described here uses the lateral (Hardinge) approach. The patient is placed on his or her side, on an ordinary operating table. The pelvis is immobilized between a pubic and a sacral support, allowing free flexion and abduction of the hip. The lower (non-operated) leg is placed on two pads, with the hip in extension and the knee slightly flexed. A lateral longitudinal incision is made, centred over the greater trochanter (Fig. ). It may be useful to establish the landmarks for limb length at this stage. This may be done by inserting one pin above the acetabulum and another pin on the greater trochanter and measuring the distance between the two points. This distance should be checked before the resection of the femoral head and again after the trial reduction. The measurement obtained at the end of the procedure must correspond with the length defined during pre-operative planning. Fig. 8

9 Surgical Protocol Neck Osteotomy The cut with the oscillating saw is started at the calcar, at the point determined during templating. Anterolateral Approach With an anterior approach the resection is started at the calcar, at a point determined from the distance of the top of the femoral head, during templating. The resection involves a single cut, which is taken to the base of the medial face of the greater trochanter. Posterolateral Approach With a posterior approach, resection involves two cuts: A first cut along an oblique line on the back of the femoral neck; this does not require any anteversion. A second, vertical cut, which runs parallel to the medial face of the greater trochanter and is routed upwards from the digital fossa. The greater trochanter is carefully preserved during the procedure. 60 Fig. 8 Neck osteotomy, using Anterolateral approach Fig. Neck osteotomy, using Posterolateral approach

10 Surgical Protocol Insertion of the Cup Following neck resection, the acetabulum is exposed and debrided, removing any osteophytes. The cup is inserted with a mean anteversion of (the angle will vary as a function of the surgical approach used). Further details concerning cup implantation can be found in the Surgical Protocol for the ABG II cup (available from Stryker). Opening of the Proximal Femur The opening is made with a box chisel of a size corresponding the intended implant and broach size (Fig. ). Chisel 8mm mm 16mm Corresponding Broaches 2, 3 4, 5, 6, 8 In order to prevent the implant being positioned in varus, the chisel should be introduced laterally, against the medial face of the greater trochanter in the digital fossa, and a 1-2cm wedge of cancellous bone should be removed. Fig.

11 Surgical Protocol Broaching The smallest broach (right or left, as appropriate) is inserted to prepare the femoral canal (Fig. 11). The broach must be positioned as vertically as possible, by entering laterally at the level of the digital fossa; the cancellous bone at the calcar should be spared as much as possible, since it provides a safeguard against varus positioning. If the femoral canal is very narrow, calibration reaming may be necessary to determine the diameter of the canal. Next, the broach/trials are inserted into the metaphysis. Surgeons who wish to use thin-layer cementing should choose an implant of the same size as that of the final broach. Surgeons who wish to use a thicker cement mantle should choose an implant one size smaller than that of the final broach. Fig. 11 ABG II Broaches/Trials Broach Size (Left & Right) Broach Length (mm) Distal Diameter (mm) Minimum Reaming Diameter* (mm) *If necessary due to patient anatomy 11

12 Surgical Protocol Trial Reduction A plastic trial head of the required size is placed on the broach/trial, and a trial reduction is performed to check hip stability and limb length (Figs. & 13). This is not a substitute for the test to be performed once the definitive stem has been cemented in. Please refer to page 14 for information relating to head position when using the full cement mantle technique. Fig. Fig. 13

13 Surgical Protocol Cementing and Insertion of the Definitive Stem This part of the procedure involves the following stages (Figs. 14 & ):- Plugging of the distal femoral canal 1cm beyond the stem tip or the distal centraliser, with a cement restrictor strong enough to withstand the pressure exerted during cement insertion Insertion of cement from distal to proximal level, using a cement gun Pressurisation of the cement Insertion of the stem with the distal centraliser (optional), care being taken to ensure the proper positioning of the stem at the proximal end; Keeping the stem steady whilst the cement is polymerising Fig. Fig. 14 SURGICAL SIMPLEX CEMENT 13

14 Surgical Protocol Choice of Definitive Head Another trial reduction with a plastic trial head is performed, to check that the femoral head neck length is correct (Fig. 16). Following the fitting of the definitive head and final reduction, the procedure is completed in the usual manner. Femoral Head Position with Full Cement Mantle Technique When using the full cement mantle technique, where the stem used is a size smaller than the broach/trial, there is a theoretical difference between the head position determined by trialling with the broach and the final position achieved with the implanted stem. This difference is dependent on the stem size and will be: Stem Size Theoretical difference in head position between broach and stem mm 3 0.5mm 4 0.4mm mm 6 1.5mm 2.16mm Note: There is no difference when using the self-locking mantle technique. Fig

15 Surgical Protocol Stryker V Heads The cemented ABG II prosthesis is compatible only with the Stryker range of V femoral heads. The V heads have a 5 taper and are available in Vitallium (Cobalt Chrome). Vitallium (CoCr) heads available: Diameter 22.2mm 28mm 32mm Short necks -4-4 Standard necks Long necks +3 +4, +8 +4, +8 Postoperative Management The patients may be mobilised and allowed to weight-bear within 1-3 days postoperatively. Generally, walking aids are used for the first month following surgery.

16 Femoral Implants Acetabular Implants ABG II Cemented Vitallium Femoral Stems* LEFT RIGHT CAT. NO. SIZE CAT. NO ABGII Broaches/Trials LEFT RIGHT CAT. NO. SIZE CAT. NO V Femoral Heads, 5 Taper HEAD NECK VITALLIUM DIAMETER LENGTH HEAD (mm) (mm) IMPLANT NO Head Trials PLASTIC HEAD NECK CONICAL DIAMETER LENGTH TRIAL (mm) (mm) ABGII 5-Hole Cup IMPLANT OUTER CUP TRIAL CAT. NO. DIAMETER CAT. NO. (mm) ABGII No-Hole Cup IMPLANT OUTER CUP TRIAL CAT. NO. DIAMETER CAT. NO. (mm) For use with ABGII No-Hole Cups - Spike CAT. NO ABGII NO-HOLE SPIKE For use with ABGII 5-Hole Cups - Spike/Screw CAT. NO ABG OBTURATOR SCREW ABG CUP SPIKE mm ABG CUP SPIKE mm 4865 ABG CUP SCREW mm 4865 ABG CUP SCREW mm 4865 ABG CUP SCREW mm 4865 ABG CUP SCREW mm 4865 ABG CUP SCREW mm 4865 ABG CUP SCREW mm 4865 ABG CUP SCREW mm ABG CUP SCREW 45mm 4865 ABG CUP SCREW mm ABG CUP SCREW 55mm 16

17 Acetabular Implants ABG II Inserts, Duration Stabilised UHMWPE (Only for use with ABGII Cups) 22.2mm Standard IMPLANT OUTER CUP TRIAL CAT. NO. DIAMETER CAT. NO. (mm) mm Hooded IMPLANT OUTER CUP TRIAL CAT. NO. DIAMETER CAT. NO. (mm) mm Cylindro-Spherical IMPLANT OUTER CUP TRIAL CAT. NO. DIAMETER CAT. NO. (mm) mm Standard IMPLANT OUTER CUP TRIAL CAT. NO. DIAMETER CAT. NO. (mm) mm Hooded IMPLANT OUTER CUP TRIAL CAT. NO. DIAMETER CAT. NO. (mm) mm Standard IMPLANT OUTER CUP TRIAL CAT. NO. DIAMETER CAT. NO. (mm) mm Hooded IMPLANT OUTER CUP TRIAL CAT. NO. DIAMETER CAT. NO. (mm)

18 Acetabular Instrumentation 18 For use with ABG II Cups X-ray Templates ABGTP02E02 ABGII Standard PE Cup 0% Magnification ABGTP06E02 ABGII Standard PE Cup 1% Magnification ABGTPE02 ABGII Standard PE Cup 1% Magnification ABGTP14E02 ABGII Standard PE Cup 1% Magnification ABGTP03E02 ABGII Hooded PE Cup 0% Magnification ABGTP0E02 ABGII Hooded PE Cup 1% Magnification ABGTP11E02 ABGII Hooded PE Cup 1% Magnification ABGTPE02 ABGII Hooded PE Cup 1% Magnification Acetabular Reamers OUTER OUTER CAT.NO. DIA. CAT.NO. DIA mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm Reamer Handle with Hudson Connection Reamer Handle with AO Tip Connection 0288 Hudson/Jacobs Adaptor Impactor for Cup Orientator Ring Cup Extractor VIS Ø 6 VIS Ø VIS 6 Ø 6 VIS Ø 6 VIS Ø 6 VIS Ø 6 45 For use with ABG II Inserts Cup Holder ABGII Hexagonal Socket Screwdriver Hexagonal Screwdriver, Standard ABGII No-Hole Cup Spikedriver Standard Screw Holding Forceps Curved Screw Holding Forceps Double Drill Guide 484 Flexible Drill 3.2mm Diameter mm Active Length 484 Flexible Drill 3.2mm Diameter mm Active Length 484 Screw Depth Gauge ABG II Acetabular Instruments Storage VIS Ø ABGII Spike, Screw, Obturator Sterilisation Case VIS Ø 6 ABGII Impactor Flanges For Standard inserts ID 22.2mm For Standard inserts ID 28mm For Standard inserts ID 32mm For Hooded inserts ID 22.2mm For Hooded inserts ID 28mm For Hooded inserts ID 32mm VIS Ø 6 VIS Ø VIS 6 Ø 6 VIS Ø 6 VIS Ø ABGII Acetabular Cup Trials, Insert Trials and Spike Tray Storage and Sterilisation Case (Empty) Acetabular Reamers Sterilisation and Storage Case (Empty) 45 VIS Ø 6 VIS Ø 6

19 Femoral Instrumentation X-ray Templates ABGTP1E01 ABGII Cemented Stem % Magnification (Self-Locking Mantle) ABGTP18E01 ABGII Cemented Stem % Magnification (Full Cement Mantle) ABGTP1E01 ABGII Cemented Stem % Magnification (Full Cement Mantle 2 & 3) Modular Hollow Chisels CAT. NO. SIZE mm mm mm ABG Flexible Reamers Length 0mm CAT. NO. DIA mm 0228 mm 0222 mm mm mm mm mm 0222 mm mm mm mm 400 Flexible Reamer Guide Length 5mm, Diameter 3.2mm Posterior Approach 1 Broach Handle (V Spigot) 401 Posterior Approach ABGII Broach Handle (V Spigot) 401 Anterior Approach ABGII Broach Handle (V Spigot) 0001 Hexagonal Screwdriver for ABGII Broach Holder (Anterior) Femoral Impactor Reduction Guide Modular Femoral Extractor V Spigot (for plastic spigot protector) Modular Femoral Extractor V Spigot (Metal) ABG II Femoral Instruments Storage ABGII Femoral Broaches, Handle and Trial Heads Storage and Sterilisation Case (Empty) ABGII Femoral Reamer and Instrumentation Tray (Empty) Fits inside # case 02 Trinkle Jacobs Adaptor 4004 AO/Trinkle Adaptor 4842 Diameter gauge for ABGII Broaches and Reamers 1

20 Stryker SA Cité-Centre Grand-Rue 2 18 Montreux Switzerland t : f : This document is intended solely for the use of healthcare professionals. The information presented in this brochure is intended to demonstrate the breadth of Stryker product offerings. Always refer to the package insert, product label and/or user instructions before using any Stryker product. Products may not be available in all markets. Product availability is subject to the regulatory or medical practices that govern individual markets. Please contact your Stryker representative if you have questions about the availability of Stryker products in your area. Products referenced with designation are trademarks of Stryker. Products referenced with designation are registered trademarks of Stryker. Literature Number: ABGBR03E02 BEN1442/REF 1.5 0/05 Copyright 04 Stryker