6Forearm in full pronation, 8-9 cm long hockey stick incision along ulnar border of distal forearm, turning radially just distal to the head of the ulna for additional 2 cm.Forearm in full pronation, 8-9 cm long hockey stick incision along ulnar border of distal forearm, turning radially just distal to the head of the ulnar for additional 2 cm
7Ioban steridrape or comparable alternative is recommended to reduce contact between the skin and implant.
8Dissection between subcutaneous tissue and the forearm fascia.
9Barrier flap design of soft tissue incorporating both fascia and proximal retinaculum based ulnarward & extending radially to the second compartment.
10Flap elevated from radial to ulnar, incorporating the capsule present over the head of the ulna for extra cushion.
11The ECU Tendon Sheath is Released to Its Distal Origin The ECU is elevated and it’s tendon sheath is released to it’s distal insertion. This prevents possible tethering of the tendon against the prosthesis.
12The ECU is elevated and it’s tendon sheath is released to it’s distal insertion. This prevents possible tethering of the tendon against the prosthesis.
14EDQM and EIP are elevated from the ulna and interosseous membrane EDQM and EIP are elevated from the ulna and interosseous membrane. Extensor mass is elevated to expose the interosseous crest of radius. The distal posterior interosseous nerve is divided to prevent avulsion from the extensor mass.
15Neck of the ulna is being prepared for osteotomy after the interosseous membrane is released.
18Interosseous membrane is divided from the crest of the radius.
19An elevator is placed volar to the radius and the ulna is levered volarly to allow exposure of the entire ulnar side of the radius.
20The Area of the Sigmoid Notch is Identified and Any Osteophytes in the area are excised
21Volar Lip often requires contouring for properradial plate placementImproper DorsallyAngulated PositionProper Position
22Reducing volar lip of radius by means of a saw blade
23A Burr can also be used to Contour the Radius for the Radial Plate Trial
24The Radial Plate Trial is Positioned on the Ulnar border of the Radius in the Area of the Sigmoid Notch. Its Volar Facing Edge is aligned with the Volar Surface of the Radius. Using .045” K-wires the Trial is temporarily fixed to the Radius
25The Volar Surface of the Radius is Visualized to Ensure Proper Placement of the Radial Plate Trial
27The Trial’s position is checked using an image intensifer The Trial’s position is checked using an image intensifer. The PA view confirms distal clearance and general alignment. The lateral view ensures the plate is neither dorsally or volarly angulated
28The center oval guide hole is drilled first to allow optional final adjustments. Care is taken to ensure the hole passes transversely through the radius without violating the dorsal or volar cortex.
29The Hole is then Tapped Prior to Introduction of a 3 The Hole is then Tapped Prior to Introduction of a 3.5 mm Cortical Bone Screw Self Tapping Screws are NOT used to Allow the Interchanging of Screws if Necessary
30With the center screw in place and proper positioning confirmed, the radial peg drill bit can be passed through the trials distal guide hole. The bit is typically inserted until its stopping plate contacts the trial. Care should be taken to ensure the peg bit Does Not violate the dorsal or volar cortex or pass through the radius.
31The proximal k-wire is removed and radiographic confirmation used to confirm final positioning. The profile of the trial with the radial peg bit in place will mimic what should be seen when it is replaced by the actual prosthesis.
32Trial alignment, screw direction - length, radial peg bit direction and depth are confirmed. If the dorsal or volar cortex is violated by the peg or screws they should be removed and redirected.
33The Radial Plate is Introduced by first inserting the Radial Plate Peg into the pre-drilled hole. Care is taken to ensure no tissues are trapped between the plate the the radius.
34A Plastic Impactor is provided to protect the Radial Plate when using a mallet for insertion
35The screw for the oval hole is first applied followed by up to 4 additional fixation screws
36Radial plate positioning checked Radial plate positioning checked. Excessive screw length should be avoided as well as contact between the peg and the distal screw.
37The forearm is placed in full pronation (radius at its shortest relative length), and the ulnar resection guide is inserted along the ulna and into the hemi-socket of the radial plate. The ulna is then juxtaposed against the guide.
38With the forearm in full pronation, the proximal edge of metal lip below the ball indicates the appropriate level of resection for a standard length ulnar stem. Should additional ulna be missing, the resection guide is marked in 1 cm increments allowing the selection of the appropriate extended ulnar stem.
39The osteotomy is made transversely through the ulna
412 mm guide wire is inserted into the ulna’s medullary canal to act as a centralizing guide.
42A cannulated drill bit is inserted over the guide wire, the medullary canal is drilled to a depth of 11 cm from the distal end of ulna. Care should be taken to ensure the bit remains within the medullary canal. This is regardless of the ulnar stem length selected.
47Contact with the Ulnar Stem is kept to a minimum during Its insertion
48During insertion the ulnar stem will meet resistance as the plasma spray engages the ulna. A plastic impactor is then used to protect the distal polished peg of the ulnar stem
49Periodically the impactor should be removed and the relationship between the radial plate and the ulnar stem checked.
50The distal Radial Plate and the distal Ulnar Stem should Care should be taken not to over insert the Ulna Stem. Regardless of the Ulnar Stem length used, the distal end of stem should be no more proximal than the distal end of the Radial Plate. This relationship will provide full support of the UHMWP ball.The distal Radial Plate andthe distal Ulnar Stem shouldbe at the same level whenthe stem is fully insertedStandard Length Ulnar Stem1 cm Extended Length Ulnar Stem
51The UHMWP ball is placed over the Distal Peg of Ulnar Stem affectively replacing the function of the articular surface of the Ulna Head
53Placement of the Radial Plate Cover, ensuring the mating surfaces are free of any interposing material and securing it with two small screws completes the Prosthesis. Care should be taken to firmly secure the screws with out stripping them. If there is any doubt, replace with new screws. The secured cover stabilizes the artificial Joint as would an intact TFC in regards to a normal DRUJ.
54Adequacy of overall positioning and Screw Length is Confirmed
55The Fascial-Retinacular Flap dissected during the approach is identified. This flap is to be positioned under the ECU and used as a barrier between the prosthesis and the ECU.
56The Fascial-Retinacular Flap under the ECU and over the prosthesis provides a cushioning barrier for the tendon.
57Barrier Flap sutured into position under the ECU tendon and the EDQM.
58With the implant rigidly in place, the skin is closed in a normal manner, bulky soft tissue dressings are used. Should any doubt exist as to the implants fixation, a short arm splint should be applied.