Orthopedic Bone Nail System - Distal Femoral Nail Surgical Technique Manual

Transcription

1 Orthopedic Bone Nail System - Distal Femoral Nail Surgical Technique Manual Note: The surgical procedures should be performed under the guidance of qualified skilled orthopedic surgeons, and this surgical technique manual is provided for information only.

2 INDEX Indications/Preoperative Planning Surgical Operation

3 Indications Femoral Shaft Fracture Distal Femoral Fracture Preoperative Planning Perform the X-rays by AP view and lateral view on the affected femur. Measure the diameter and length of the femoral medullary cavity. Determine the diameter and length of the nail.

4 Surgical Operation 1. Position patient Position the patient in the lateral decubitus or supine position on a fracture table or radiolucent operating table. Position the C-arm to allow visualization of the distal femur in both the AP and lateral planes. To facilitate access to the medullary canal, place a pad on the posterior knee-joint of the affected side and abduct the affected knee-joint by approximately with the ankle joint in the center position. Note: The patella will affect the nail insertion if the knee joint was abducted by more than Reduce fracture Perform closed reduction as much as possible for the fracture broken ends by axial traction under image intensifier control. The intra-articular fracture should be fixed by applying cancellous screws, ensuring that the screws are in correct position so to save the channel for the nail.

5 3. Approach and entry point Make a 3~5cm straight incision in the central patellar tendon. The incision extends from the lower patella to about 1cm above the tibial tubercle. Cut open along the longitudinal fiber of the patellar tendon. The Tissue Protector ( ) could be used in the operation afterward. Expose the femoral intercondylar fossa; the insertion point is 5~10mm anterior to the starting point of posterior cruciate ligament, in the centre point of the intercondylar fossa trochlea. 4. Open Femur Open in the entry point using Reverse Awl ( ) and gradually drill into the femoral medullary cavity with protecting the soft tissue. Remove the awl after finishing the opening. Note: The opening direction should be in line with the central axis of the intramedullary canal.

6 5. Insert guide wire Insert the Guide Wire, with olive head ( ) into the medullary cavity through the fracture line and check its position under image intensifier. Ensure that the length of the inserted guide wire in the proximal medullary cavity meet the requirement for fixation.

7 6. Confirm the nail length Measure the length of the exserted guide wire, L 2, and subtract it from the overall length L 1, then the required nail length L= L 1 - L 2. Note: Reconfirm it by comparing with the preoperatively measured length. 7. Ream medullary cavity Slide the Flexible Reamer, with quick coupling ( ) and gradually enlarge the canal, generally start from the smallest size and increase the diameter of the reamer accordingly until it becomes 1.0mm larger than the selected nail, which could avoid condylar displacement when inserting nail. Remove the reamer without extracting the guide wire. Note: Maintain reduction of the fracture in the process of reaming and the operation afterwards.

8 8. Calibrate nail A Connect the nail on the Short Aiming Arm ( ) using the Cannulated Connecting Screw ( ) and tighten it with the Wrench ( ). B Assemble the Long Aiming Arm ( ) and make it in line with the nail. Tighten the Screw for Aiming Arm ( ) by Wrench ( ). C Install the Protection Sleeve ( ) and L-Handle Drill Sleeve ( ) in the positioning holes of the locking screws for the selected nail and insert the drill bit ( ). The calibration is completed if the drill bit can smoothly pass through the holes. Remove the Screw for Aiming Arm ( ) and disassemble the Long Aiming Arm ( ). Note: Ensure that each joint of the aiming arm and nail is firmly connected, or it will lead to calibration error and failed implantation.

9 9. Insert Nail For cannulated nail, select the Guide Wire, without olive head ( ) and slowly insert the nail along the Guide Wire into the medullary cavity. Then remove the Guide Wire when the nail is fully inserted; for solid nail, just remove the Guide Wire and insert the nail by hand as far as possible twisting gently. If necessary when there is great resistance, insert the nail using light hammer blows on the Short Aiming Arm ( ) with either the Hammer ( ) or with the Inserter-Extractor for Distal Femoral Nail ( ). Note: Ensure that the bone fracture is reduced and maintain the line of force so to prevent varus, valgus or rotation deformity. The distal end of the nail should be placed 2 to 5 mm beyond the articular cartilage so to make sure that the nail and the end cap won t penetrate through the surface of the articular cartilage. Reconfirm that every connecting screws is firmly fixed.

10 10. Assemble distal locking screws A Assemble the Long Aiming Arm ( ) and make it in line with the nail. Tighten the Screw for Aiming Arm ( ) by Wrench ( ). Install the Protection Sleeve ( ) and Trocar ( ) on the Long Aiming Arm. Make a small incision in the fixed position of the trocar and bluntly separate the soft tissue to the bone surface. Insert the Protection Sleeve until it contacts the bone surface, and then remove the trocar. B Slide the L-Handle Drill Sleeve ( ) into the Protection Sleeve until it reaches the bone surface. Connect the Drill Bit φ4.2mm ( ) on the power drill and drill through both bone cortices along the L-Handle Drill Sleeve. Stop drilling when the power drill passes through the opposite bone cortex. Note: Do not press the aiming device during drilling so to ensure an accurate drilling hole position.

11 C Remove the L-Handle Drill Sleeve and place the Depth Gauge ( ) along the Protection Sleeve to measure the length for the Locking Screw. Note: The Protection Sleeve must directly contact bone surface to achieve an accurate measurement.

12 D Tighten up the 4.9mm Locking Screw of proper length using the φ4.0 mm Hexagonal Screwdriver ( ). It is firmly locked when the 0 tick mark touches the the end of the Protection Sleeve. Note: Read the length of the Locking Screws directly from the Depth Gauge. E Repeat the same operation as described above to insert the rest Locking Screws. Verify locking screw length under image intensification to ensure a correct position. Note: There are three Locking Screws in the distal end. Place two or three Locking Screws according to the fracture condition. Screw both the proximal and distal screws from the lateral direction.

13 11. Assemble proximal locking screws A Recheck the fracture reduction under image intensifier. Insert the Protection Sleeve ( ) and Trocar ( ) in the proximal hole of the Long Aiming Arm. Make a small incision in the fixed position of the trocar and bluntly separate the soft tissue to the bone surface. Insert the Protection Sleeve until it contacts the bone surface, and then remove the trocar. Note: There are two locking holes in the proximal end of the nail, generally, advance the nearest Locking Screw.

14 B Slide the L-Handle Drill Sleeve ( ) into the Protection Sleeve until it reaches the bone surface. Connect the Short Drill Bit φ4.2mm ( ) on the power drill and drill through both bone cortices along the L-Handle Drill Sleeve. Stop drilling when the power drill passes through the opposite bone cortex. Keep the short drill bit in the hole channel and repeat the same operation as described above to drill through both bone cortices using the long drill bit.

15 C Remove the L-Handle Drill Sleeve and place the Depth Gauge ( ) along the Protection Sleeve to measure the length for the Locking Screw. Note: The Protection Sleeve must directly contact bone surface to achieve an accurate measurement. D Tighten up the 4.9mm Locking Screw of proper length using the φ4.0 mm Hexagonal Screwdriver ( ). It is firmly locked when the 0 tick mark touches the end of the Protection Sleeve. Verify locking screw length under image intensification by AP view to ensure a correct position. Note: Read the length of the Locking Screws directly from the Depth Gauge.

16 E Remove the Short Drill Bit and Protection Sleeve. Repeat the same operation as described in procedures C and D to insert the other Locking Screw. 12. Insert end cap Remove the insertion instruments. Pick the End Cap by the Screwdriver Shaft

17 ( ). Using the φ5.0 mm Cannulated Hexagonal Screwdriver ( ), align the end cap with the nail axis and fix it by means of the Protection Sleeve. Note: To minimize the chance of cross-threading, turn the End Cap counterclockwise until the thread of the End Cap aligns with that of the nail. By turning clockwise, completely screw the End Cap into the nail, so that the locking screw is fixed. The last turns will offer some resistance caused by a groove in the thread which prevents the screw from loosening. Tighten the End Cap firmly. Alternative If it s difficult to lock the End Cap by the Screwdriver Shaft, remove the Aiming Arm. Insert the φ2.5 mm Guide Wire (Length 250 mm) along the nail, and then use the φ5.0 mm Cannulated Hexagonal Screwdriver ( ) to screw the End Cap by means of the Guide Wire.

18 13. Implant removal 13.1 Remove end cap and locking screw Following the primary operation approach, remove the ingrown tissue from the hexagonal recess of the end cap and the locking implants. Unscrew the End Cap using the φ5.0 mm Cannulated Hexagonal Screwdriver ( ). Remove the Locking Screw by the φ4.0 mm Hexagonal Screwdriver ( ). Before removing the last Locking Screw, attach the Cannulated Connecting Screw ( ) and the Inserter-Extractor ( ) on the nail, using the Wrench ( ) to tighten it firmly. Leave a Locking Screw in the hole to avoid the nail from rotating or falling into the canal.

19 13.2 Remove nail Remove the last Locking Screw. Knock the nail out with gentle blows of the slide hammer.