1. Hamstring Tendon Autograft for ACL Reconstruction
BS. Nguyễn Trọng Anh

2. INTRODUCTION
The success of anterior cruciate ligament (ACL) reconstruction:
Initial tensile properties of the graft tissue
The initial fixation of the graft,
The healing at the graft fixation sites,
The biologic remodeling of the graft,
Type of postoperative rehabilitation program used.

3. patellar tendon autograft: “gold standard” for ACL reconstruction.
Four-stranded hamstring tendon autografts have become an increasingly popular graft choice for ACL reconstruction

4. Strong points:
Biomechanically, as strong as PTB.
Faster recovery of quadriceps muscle strength.
Lower incidence of donor site pain.
Less interference with kneeling and crawling.

5. History and Physical Examination
Initial injury and subsequent injuries and previous treatment.
Lachman and pivot shift tests

6. Imaging
XRAY: associated bone injury, joint space narrowing, skeletal maturity.
A true lateral view in maximum hyperextension  preoperative planning of the tibial tunnel in the sagittal plane.
Blumensaate line

7. MRI

8. Associated injuries to the PL, PM, other structures
Associated injuries to the PL, PM, other structures.  continued complaints of instability or failure of the ACL reconstruction.

9. Indications and Contraindications
Acute or chronic ACL reconstruction.
Pt whose occupation, lifestyle, or religion requires “knee walking,” crawling, or kneeling.
Pt with patellofemoral pain or patellar tendinopathy.
Pt with open growth plates.
Absolute contraindication: previous harvest of the hamstring tendons.
Caution: Significant loss of knee flexor strength at high flexion angles at athletes require maximum flexor strength at high angles of flexion. gymnasts, wrestlers, sprinters, and American football…

10. Femoral Fixation Options
Loop suspension + cross pins provide strong femoral fixation with minimal slippage during cyclic loading:
Fixation strength is high.
Slippage during cyclic loading is minimal.
The fit of the tendon in the bone tunnel is tight.

11. The 360 degrees of contact between the bone tunnel wall and the hamstring tendon graft enhances healing.
The amount of graft inserted into the femoral tunnel can be customized.
Removal of the implant is not required in revision cases.
Fixation properties are not dependent on the bone quality of the distal femur.

12. Tibial Fixation Options
Weak link of ACL graft fixation.
Tibial fixation of hamstring tendon grafts remains: lower bone mineral density of the proximal tibia, fixation devices must resist shear forces applied parallel to the axis of the tibial bone tunnel.

14. Surgical Technique General or regional anesthesia.
A padded pneumatic tourniquet
Supine positon
The leg holder, dropping feet

15. 1. Hamstring tendon graft harvest
Graft preparation
Arthroscopic portal placement
Preparation of the intercondylar notch
Femoral tunnel
Tibial tunnel
Calculation of femoral fiaxation syst. Length and graft preparation
Graft passage and femoral fixation
Graft tensioning
10. Tibial fixation
11. Closure

16. Hamstring Tendon Graft Harvest

17. Graft Options: Hamstring harvest1 2 3 4

18. Graft Preparation Place sutures in ends
Double the semi-t and gracilis over a #5 Ticron
Whip stitch the proximal end with #0 Vicryl
Suture the distal end with Krakow, #2 Ticron
Measure the size of the 4 bundles

19. Endobutton

20. Portal Placement AnteroLateral Anteromedial Anteromedial
Oblique, middle of soft spot
Anteromedial
AnteroLateral
Low anteromedial above medial meniscus, next to patellar tendon
Low anteromedial above medial meniscus, next to patellar tendon

21. Diagnostic Arthroscopy

22. ACL Stump Debridement Debridement of the ACL stump
to avoid anterior impingement
remove fat in notch to visualize posterior fringe

23. Notchplasty Notchplasty -
only sufficient bone to accommodate the graft
visualize the posterior fringe

24. Tibial Tunnel Tibial Guide: Set 45-500 External Landmarks
5 cm below joint line
2 cm from mid line( in sagital plane)

25. Drill same size as 4 bundle graft
Internal Landmarks
5 mm from PCL
Midline
Posterior to the lateral meniscus edge
Drill same size as 4 bundle graft

29. Femoral Tunnel - Endo Linvatec guide >8 mm use the 7 mm guide
Positon: 2 or 10 o’clock position

30. Transtibial tunnel:
Advantages
not requiring the knee to be flexed to 120 degrees during drilling of the femoral tunnel. Joint distention and the field of view in the intercondylar notch not compromised.
producing longer femoral tunnels in the range of 40 to 50 mm  advantageous for the EndoButton CL fixation technique  more graft in the femoral socket. Implant resting on the stronger cortical bone of the distal femur.
Disadvantage:
Free positioning of the femoral tunnel in the intercondylar notch is not possible

32. anteromedial portal technique:
Advantages:•
femoral tunnel in a more anatomic position
freedom to locate the starting position of the tibial tunnel anywhere along the medial surface of the tibia.
steeper and longer tibial tunnel
Disadvantage:
limits joint distention and provides a more unconventional field of view in the notch that can result in spatial disorientation.
more horizontal femoral tunnel EndoButton implant's lying on the weaker metaphyseal bone of the distal femur

34. Femoral fixation
Interference screws
Endobutton
Cross pin

35. Endobutton and graft passage
Tension on both ends of leader sutures

36. Securing endobutton on femoral cortex

37. Tibial fixation
Tension put on the graft.
Graft fixed with bioscrew

38. The stability and ROM check.
Graft tension and impingement are assessed.
After confirmation that the patient has a full range of motion and negative Lachman, passing and flipping sutures are pulled out of the lateral thigh.
Closed drainage??
Skin closure

39. Postoperative Management
Follow-up
The patient is seen at 7 to 10 days for suture removal and postoperative radiographs

40. D’Amato, Bach & Wilk (Handbook of Orthopeadic Rehabilitation, Kevin E
D’Amato, Bach & Wilk (Handbook of Orthopeadic Rehabilitation, Kevin E.Wilk, 2007)
5 phases
Week 1-2: Light exercises, protect graft fixation, diminish swelling.
Week 2-4: Restore gait, ROM, prevent muscle atrophy.
Week 4-10: Muscle strength exercises, functional motion, prevent overload.
Week 10-16: Return daily activities
Week 16+: Gradually return sports activities

41. Complications
infection, deep venous thrombosis, and loss of motion
premature amputation of the hamstring tendons, saphenous nerve injury, bleeding at the hamstring tendon harvest site.

42. AANA OLC
Rosemont, Illinois 10/2003
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