LARS ligaments are intended for the intra or extra-articular reconstruction of ruptured ligaments.
LARS can be used in conjunction with suturing to the remnant of the ruptured ligament, or as an autogenous reconstruction. In both cases LARS allows the original ligament tissues to heal in the absence of traction and provides an earlier return to normal function. LARS can be used for extra-articular reconstructions in tendon repair, such as Achilles tendon, patella tendon, biceps tendon, rotator cuff etc.
These ligaments must always be placed in the joint in an anatomical and isometric position. The diameter of the bony tunnels must correspond to the specific reference for each type of ligament and as a general rule should be as small as possible. The fixation of the ligament extremities must always be extra-articular. In acute cases, the artificial ligament must be placed at the centre of the autogenous remnant. Ligament extremities are cut flush with the fixation.
Biological and mechanical testing on resistance, fatigue and creep have shown that LARS ligaments are highly effective ligament reconstruction and augmentation devices, and long-term clinical results are excellent. The use of the LARS artificial ligament requires a specific surgical technique, for which dedicated LARS instruments are available.
A number of guidelines must be respected:
- Isometry is critical to the outcome
- Acute angles must be avoided in the drilling of the bony tunnels
- There must be no impingement or abrasion of the ligament in the joint
- Solid extra-articular fixation must be achieved using LARS interference screws
- Absence of tension in the synthetic ligament is important; the post-operative tension should not be more than that of the anatomical ligament being repaired
- Coverage by fibrous tissue is desirable, in particular when placing the ligament under arthroscopy; it is contraindicated to remove all remnants in the intracondylar notch; the ligament must pass through this tissue
- Small incisions should be used to retain proprioception (1) (2)