FMP Surgical Technique

Transcription

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2 Contents Design Rationale....3 Indications Contraindications Preoperative Planning Surgical Snapshot Surgical Technique Sizing Chart Instrument Guide Individual results may vary. DJO Surgical is a manufacturer of orthopedic implants and does not practice medicine. This surgical technique was prepared in conjunction with licensed health care professionals. The treating surgeon is responsible for determining the appropriate treatment, technique(s), and product(s) for each individual patient. 2

3 System Features THE FMP ACETABULAR SYSTEM CONSISTS OF THE FOLLOWING: Porous hemispherical acetabular shell with clustered screw holes Porous hemispherical acetabular shell without screw holes Porous hemispherical acetabular shell with three spikes Porous hemispherical acetabular shell with multiple screw holes Porous flared rim acetabular shell with clustered screw holes Porous flared rim acetabular shell without screw holes Various compression molded, X-alt, and HXe+ highly Cross-Linked polyethylene liners Constrained Liner 22, 28, 32, 34, 36, 40 and 44mm modular CoCr femoral heads 28, 32, 36, 40 and 44mm BIOLOX delta and BIOLOX OPTION ceramic femoral heads The six metal-backed porous coated acetabular shells feature a thin-wall design allowing for maximum polyethylene thickness of the acetabular liners. All are designed and manufactured with high congruency between the modular liner and the Titanium metal shell. The snap-fit acetabular liners are available in neutral, 10, 20, neutral with a 5mm offset and 10 with a 5mm offset. All Non-Crosslinked liners are sterilized by gamma radiation in a nitrogen-flushed environment. Sterilization of the Highly Cross-Linked Polyethylene Acetabular Liner, and Highly Cross-Linked Polyethylene Vitamin E Acetabular Liner, are performed by hydrogen peroxide gas plasma to achieve a Sterility Assurance Level (SAL) of The flared rim shell provides an additional 2mm of press-fit for increased stability, while the spiked cup features three spikes for increased rotational stability. The bipolar features a modular snap-fit design utilizing 22mm and 28mm modular femoral heads. The unipolar heads range in size from 38-64mm and feature five neck adaptor sleeve options. 3

4 Indications, Contraindications, and Preoperative Planning INDICATIONS Joint replacement is indicated for patients suffering from disability due to: Noninflammatory degenerative joint disease including osteoarthritis and avascular necrosis of the natural femoral head Rheumatoid arthritis Correction of functional deformity Femoral fracture This device may also be indicated in the salvage of previously failed surgical attempts. The constrained acetabular component is indicated for primary or revision patients at high risk of hip dislocation due to a history of prior dislocation, bone loss, soft tissue laxity, neuromuscular disease, or intra-operative instability and for who all other options to constrained acetabular components have been considered. This device is to be used for uncemented applications. supported smooth articulation of the head within the acetabulum; Alcoholism or other addictions; Materials sensitivity; Loss of ligamentous structures; High levels of physical activity (e.g. competitive sports, heavy physical labor); Pregnancy PREOPERATIVE PLANNING Preoperative templates are provided for estimating the optimal acetabular component size. Radiographs should include a full A/P (anterioposterior) and lateral view of the pelvis. As with any surgical procedure, proper radiographs are recommended for accurate templating. The dotted line of the shell represents the outer dimension of the porous shells. The flared rim design is 2mm larger (1mm per side) at the rim (FIGURE 1). CONTRAINDICATIONS Joint replacement is contraindicated where there is: Infection or sepsis; Insufficient bone quality which may affect the stability of the implant; Muscular, neurological or vascular deficiencies, which compromise the affected extremity; Skeletally immature patients and cases where there is a loss of abductor musculature, poor bone stock, poor skin coverage around the hip joint which would make the procedure unjustifiable; Osteomyelitis; Rapid joint destruction or bone absorption apparent on roentgenogram; Pathological conditions of the acetabulum, which would prevent achieving proper range of motion, appropriate head stability, and/or a well-seated and FIGURE 1 4

5 Surgical Snapshot Sequentially ream until good contact is made with the cortical rim. Once the final shell implant size has been determined, remove the dome plug using the hexdriver. Attach the shell to the shell impactor and impact into the acetabulum If using a cluster hole shell, bone screws may now be implanted. The bone screw must be fully seated to ensure engagement of the trial liner or liner implant. Place the trial liner in the shell implant and fully thread the screw using the hexdriver. Once the liner implant has been selected, impact the liner into the shell until the snap locking mechanism engages. 5

6 Surgical Technique FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 SURGICAL APPROACH The FMP Acetabular System is designed to accommodate any standard approach based on the surgeon s experience or personal preference. Adequate exposure, which allows bony landmark visualization, component alignment, and thorough soft-tissue assessment should be considered throughout the procedure. ACETABULAR PREPARATION The acetabular rim is exposed by thorough removal of the acetabular labrum. The acetabular fat pad and any osteophytes are removed to identify the true acetabular floor. An acetabular reamer is used to deepen the true acetabular floor. Placing each reamer concentrically into the acetabulum, the reaming progresses until good contact is made with the cortical rim. In a shallow acetabulum, it may be necessary to ream to the medial cortical wall. In an eccentrically deep acetabulum, the cotyloid notch may be left intact. All cysts are curetted and subsequent defects may be packed with cancellous bone obtained from the resected femoral head or acetabular bone reamings. The final reamed diameter should be the same as or 1mm smaller than the selected implant size, depending on the quality of the bone. In normal to sclerotic bone, a line-to-line reaming is sufficient. When using a P2 shell, line-to-line reaming is recommended. In soft bone, under reaming by 1mm may be necessary. If the flared rim cup is selected for implantation, a line-to-line reaming will allow 2mm pressfit around the rim of the acetabulum. If the acetabulum is under reamed by 1mm, a flared rim cup will allow a 1mm press-fit over the hemisphere and a 3mm press-fit around the rim of the acetabulum. Shell trials are available in even sizes in 2mm increments to verify the reamed diameter. The shell trial should make even contact with the rim and walls of the acetabulum and provide feedback that the acetabulum has been prepared adequately for the final implant. ACETABULAR PLACEMENT The dome plug is removed from the acetabular shell (FIGURE 2) and the shell is fully threaded to the shell impactor (FIGURE 3). If a screwhole design shell is selected, the cluster of screwholes may be positioned to the posterior/superior quadrant of the acetabulum. If an alignment guide is used, ensure the alignment rods are aligned with the screwholes. The T-handle is inserted in either the 15 or 20 position depending on the desired degree of anteversion. The alignment rod is threaded into either the left or right alignment hole of the positioner (FIGURE 4). Positioning the T-handle vertical to the floor gives approximately 45 of abduction. Then, positioning the alignment rod parallel to the patient s midline gives approximately 20 or 15 of anteversion depending on the selected position of the alignment rod (FIGURE 5). 6

7 Surgical Technique FIGURE 6 ACETABULAR PLACEMENT CONTINUED When using the straight cup impactor, part number , (FIGURE 6) one of the three modular impaction tips must be used when impacting the shell. Place the impaction tip over the straight cup impactor threads until you feel it snap into place. The impactor threads should be exposed to screw into the shell. The small tip should be used for shell sizes 40-46mm, the medium tip for 48-58mm, and the large tip for 60-70mm. With this straight cup impactor there are two alignment guide options: supine and lateral. The guides will provide 20 degrees of anteversion (vertical rod for supine guide, horizontal rod for lateral guide) and 45 degrees of inclination (horizontal rod for supine guide, vertical rod for lateral). First, thread an alignment rod into the threaded hole on top of the selected guide. Thread the second alignment rod into either the left or right threaded hole. Place the assembly onto the handle of the impactor with the guide label and description facing the modular impaction tip. Rotate the guide into the desired position and secure by tightening the knob. When the horizontal alignment rod aligns with the patient s spine and the vertical rod is perpendicular to the floor, the handle will be oriented at 20 of anteversion and 45 of inclination. 7

8 Surgical Technique FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 SCREW PLACEMENT The flexible drill shaft and drill bit are guided by the drill guide through the desired screw hole (FIGURE 7). The drill guide is 15mm in length and the drill bits are available in 45mm or 60mm lengths and 3.2mm or 4.5mm diameters. The working length of the drill bit extending from the drill guide is 30mm and 45mm respectively. A depth gauge is provided to determine the length of the screw needed and to verify that the internal cortex has not been penetrated (FIGURE 8). NOTE: The bone screw must be fully seated to ensure full seating of the trial liner or liner implant. (FIGURE 10). The appropriate cancellous bone screw is inserted using the universal joint screwdriver and the screw forceps (FIGURE 9). 8

9 Surgical Technique FIGURE 11 FIGURE 12 FIGURE 13 LINER TRIALING AND IMPLANTATION The appropriate liner is determined for joint stability. Polyethylene liners are available in neutral, 10 and 20 hooded, neutral with a 5mm offset, 10 with a 5mm offset, and constrained. The 12-position scallops on the various liners allow independent rotation of the liner to the point where additional femoral head coverage is desired. Trial liners can be threaded into the implant shell so that a trial reduction can be performed to assist in final implant selection (FIGURE 11). At this point, measurements of the offset and neck length can be compared to the preosteotomy measurements, but may need to be adjusted to ensure stability depending on final acetabular component seating and anteversion of the femoral stem. Neck length can be adjusted using the various offsets of the femoral head and offset sleeve implants. NOTE: The use of offset sleeves is required with 34, 36, 40 and 44mm CoCr heads. Once the appropriate liner has been determined, the trial liner can be removed and the dome plug can be replaced into the shell (FIGURE 12). The final liner implant is then impacted into the shell using the liner impactor head that corresponds to the implant head size being used (FIGURE 13). Visually confirm symmetrical seating of the polyethylene liner. An osteotome can be lightly inserted between the shell and the inserted liner. Gently attempt to pry upward on the polyethylene liner. There should be no movement of the liner within the shell. If the liner disengages, repeat the impaction until the snap-feature engages. Range of motion typically increases as femoral head size increases 1. If using a smaller femoral head, it is important to verify that sufficient range of motion is achieved. 9

10 Surgical Technique BIOLOX DELTA CERAMIC FEMORAL HEADS If a BIOLOX delta femoral head is being implanted, do not remove the plastic protective wrap until immediately before the trial head is used. The BIOLOX delta femoral heads may only be used on brand new, unused femoral stem tapers. Before placing the BIOLOX delta head onto the trunnion of the femoral stem, thoroughly rinse and dry the stem taper. Inspect the stem and inner taper of the ceramic head and carefully remove any tissue, bone, or foreign substances. Lightly twist the BIOLOX delta head onto the trunnion until it sits firmly. Using the plastic femoral head impactor, moderately tap the mallet so the ceramic head is firmly and definitively fixed onto the femoral stem taper. The metal taper becomes plastically deformed during impaction, thus producing an optimal pressure distribution and torsion-resistant fixation. It is essential for safe function that the greatest care is taken when placing the BIOLOX delta femoral head on the stem. NOTE: In very isolated cases, fracture of ceramic components can occur. The cause of this can be an overload on the prosthesis. For example, through incorrect placement of the BIOLOX delta head on the stem taper or a wrong or missing fit between the BIOLOX delta head and the stem taper. If a ceramic femoral head breaks, a pairing of a metal femoral head with a polyethylene liner may not be used for revision. Never impact the BIOLOX delta or BIOLOX OPTION heads with a metal mallet. A plastic femoral head impactor must always be used. Any reuse or re-sterilization of the BIOLOX OPTION femoral heads is not permitted. BIOLOX OPTION CERAMIC FEMORAL HEADS If a BIOLOX OPTION femoral head is being implanted, the stem taper, femoral head sleeve, and ceramic femoral head must be dry and free of any foreign substances: tissue or bone before the final seating. Lightly twist the BIOLOX OPTION head onto the trunnion until it locks. It should be easy to place the femoral head onto the taper and if any pressure is necessary, the implant must not be used. Using the plastic femoral head impactor, moderately tap the mallet so the ceramic head is firmly and definitively fixed onto the femoral stem taper. The interface between the metal sleeve and the stem taper becomes plastically deformed during impaction, thus producing an optimal pressure distribution and torsion-resistant fixation. Ensure the BIOLOX OPTION femoral head is well fixated by attempting to remove the femoral head by hand. When using the BIOLOX OPTION femoral head on an already compromised stem taper, the surgeon must test the taper for its compatibility with the inner taper of the femoral head sleeve. 10

11 Surgical Technique FIGURE 14 FIGURE 15 If a constrained liner is being used, use standard trial liners and 28mm head trials to determine appropriate femoral head offset. Once the desired sizing has been determined, impact the constrained liner implant using a 28mm ball impactor. To assemble the constrained liner components, first impact the femoral head implant onto the taper of the stem implant. Next, slide the constrained locking ring over the neck of the femoral stem implant so that the locking feature is oriented to correctly engage the liner. Insert the femoral head into the constrained liner (FIGURE 14). Last, snap the locking ring onto the locking scallops of the constrained liner (FIGURE 15). This can be achieved by hand. 11

12 Reference Guide The FMP system uses letters, colors and numbers to designate compatibility between all components. Matching shell and insert codes will ensure proper compatibility. For more implant part numbers and information, please refer to the Acetabular Reference Guide (catalog number ). COLOR/CODE STANDARD SHELL SIZE SPIKED SHELL SIZE ID/HEAD SIZE NEUTRAL/0 10 HOODED 20 HOODED 5MM OFFSET NEUTRAL/0 5MM OFFSET 10 HOODED MIN POLY THICKNESS HXE+ X-ALT HXE+ X-ALT HXE+ X-ALT X-ALT X-ALT STD SHELL MP1* 40 N/A 22mm 5.6mm MP2* 42 N/A MP3 44 N/A MP4 46 N/A MP /50 MP MP MP MP9 56/58 58/60 MP10 60/62 62/64 MP11 64/66 66/68 MP12 68/70 70 MP13* 72/74 N/A MP14* 76/78 N/A MP15* 80 N/A HXE+ AND X-ALT HIGHLY CROSS-LINKED LINERS 22mm 6.7mm 28mm mm 22mm* 7.6mm 28mm mm 28mm mm 32mm mm 28mm mm 32mm mm 32mm mm 34mm mm 36mm mm 32mm mm 36mm mm 32mm mm 36mm mm 40mm mm 32mm mm 36mm mm 40mm mm 32mm mm 36mm mm 40mm mm 44mm mm 32mm mm 36mm mm 40mm mm 44mm mm 32mm mm 36mm mm 40mm mm 44mm mm 36mm mm 40mm mm 44mm mm 36mm mm 40mm mm 44mm mm 36mm mm 40mm mm 44mm mm 12 *Denotes special request *22mm liners (MP1-MP3) available in compression molded only. *Poly thickness is measured 30 degrees from the dome.

13 Reference Guide INSTRUMENT GUIDE 2 1 FMP Acetabular Case #1 - Reamers 1. ACETABULAR REAMER HANDLE (X2) ACETABULAR REAMERS 44mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm *For smaller or larger reamer information, contact your Customer Service representative. 13

14 Reference Guide INSTRUMENT GUIDE FMP Acetabular Case #2 - Trial and Screw: Upper Tray FMP Acetabular Case #2 - Trial and Screw: Lower Tray 1. RATCHETING HANDLE U-JOINT MODULAR SHAFT DRILL BITS 3.2 X 60mm X 60mm X 45mm X 45mm BONESCREW DRILL GUIDE SCREW FORCEPS DEPTH GAUGE FLEXIBLE DRILL SHAFT* STRAIGHT HEXDRIVER *The flexible drill shaft, #7, is now located in the compartment with the straight hexdriver, #8. 1. ACETABULAR TRIAL SHELLS 44mm mm mm mm mm mm mm mm mm mm mm ACETABULAR SHELL IMPACTOR/POSITIONER ALIGNMENT ROD LINER IMPACTOR HANDLE TRIAL LINERS, 22MM, 10 HOODED MP MP MP

15 Reference Guide INSTRUMENT GUIDE 1 2 X-alt Instrument Case 1: Upper Tray 1. FMP ACETABULAR TRIAL LINERS NEUTRAL 28mm ID 46mm CUP OD mm ID 48mm CUP OD mm ID 50mm CUP OD mm ID 50mm CUP OD mm ID 52mm CUP OD mm ID 54mm CUP OD mm ID 56mm CUP OD mm ID 60mm CUP OD mm ID 64mm CUP OD mm ID 68mm CUP OD FMP ACETABULAR TRIAL LINERS 10 HOODED 28mm ID 46mm CUP OD mm ID 48mm CUP OD mm ID 50mm CUP OD mm ID 50mm CUP OD mm ID 52mm CUP OD mm ID 54mm CUP OD mm ID 56mm CUP OD mm ID 60mm CUP OD mm ID 64mm CUP OD mm ID 68mm CUP OD

16 Reference Guide INSTRUMENT GUIDE X-alt Instrument Case 1: Lower Tray 1. HXL TRIAL HEADS 22mm +8.0mm mm mm mm mm mm mm mm NEUTRAL NEUTRAL NEUTRAL NEUTRAL mm mm mm HXL TRIAL HEADS 28mm 4. HXL TRIAL HEADS 34mm 6. HXL TRIAL HEADS 40mm 8. CERAMIC TRIAL HEADS 44mm +10.5mm mm mm mm mm mm mm mm mm mm mm NEUTRAL NEUTRAL NEUTRAL NEUTRAL mm mm mm mm DELTA CERAMIC TRIAL HEAD 32MM, +7.0mm HXL TRIAL HEADS 32mm 5. HXL TRIAL HEADS 36mm 7. HXL TRIAL HEADS 44mm +12.0mm mm mm

17 Reference Guide INSTRUMENT GUIDE X-alt Instrument Case 2: Upper Tray 1. LINER IMPACTOR HANDLE (LONG) SLEEVE EXTRACTOR HANDLE* SLEEVE EXTRACTOR* FEMORAL HEAD IMPACTOR HANDLE FEMORAL HEAD IMPACTOR BALL HEAD ADAPTER 22mm LINER IMPACTOR HANDLE (SHORT) *Numbers 2 and 3 work together to extract the femoral head sleeve. 8. CERAMIC TRIAL HEADS 36mm -4.0mm NEUTRAL mm mm CERAMIC TRIAL HEADS 40mm -4.0mm Neutral mm mm

18 Reference Guide INSTRUMENT GUIDE X-alt Instrument Case 2: Lower Tray 1. ACETABULAR SOMBRERO LINER IMPACTORS 20 HOOD 28mm mm mm mm mm mm mm ACETABULAR SOMBRERO LINER IMPACTORS 10 HOOD 28mm mm mm mm mm mm mm ACETABULAR SOMBRERO LINER IMPACTORS NEUTRAL 28mm mm mm mm mm mm mm ACETABULAR LINER IMPACTOR BALLS 22mm* mm mm mm mm mm mm mm *Use 22mm ball head adapter ( ) in conjunction with liner ball impactor. 18

19 Reference: 1. Crowninshield, et al. (2004). Biomechanics of Large Femoral Heads: What They Do and Don't Do. CORR Vol. 429, pp Individual results may vary. DJO Surgical is a manufacturer of orthopedic implants and does not practice medicine. This surgical technique was prepared in conjunction with licensed health care professionals. The treating surgeon is responsible for determining the appropriate treatment, technique(s), and product(s) for each individual patient.. DJO Surgical I A DJO Global Company T D F Metric Blvd. I Austin, TX I U.S.A. djoglobal.com/djosurgical CAUTION: Federal Law (USA) restricts this device to sale by or on the order of a physician. See package insert for a complete listing of indications, contraindications, warnings, and precautions Encore Medical, L.P. MKT Rev G 1/18