LARS Ligament What’s the fuss all about?
Feb 25, 2016
LARS LigamentWhat’s the fuss all about?
Media Love LARS
• “Miracle op to melt down surgeons' phones”
• “Is LARS revolution about to start?”
• “Rodan's LARS recovery stuns coaches”
• “Rodan back two weeks after knee surgery”
Players, Coaches and Clubs Love LARS
Club Doctors Love LARS
• "It's a ridiculous recovery,“ • "This will become the norm"
High Level of Patients Awareness
• Asking for them or about them.
Lots of Hype – Evidence based answers
• Should we be incorporating this graft into our practice?– Better than autograft?– Durability?– Do they cause OA?– Can they be revised?
• Which patients should it be used on?– Any Specific Advantages?– Optimal time to insert?
LIGAMENT ADVANCEDREINFORCEMENT SYSTEM (LARS) ARTIFICIAL LIGAMENT
• Polyethylene Terephthalate (PET).
• PET - Encourage ingrowth
• Intra-articular segment– Twist
Methods
• A systemic review process was undertaken
• Any article reporting on outcomes of the LARS ligament
10 Specific Outcomes Measures
• Loss of Range of motion (flexion or extension loss > 5 degree) • Lachman Grade >II• Pivot shift grade >II• IKDC score (% of patients scored A or B)• Lysholm score and Tegner Score• KT-1000• Muscle strength (flexion and extension strength), • Surgery Complications
– Specifically graft rupture or revision, – synovitis – osteoarthritis
LARS Literature
• 12 papers found reporting on the LARS
• 6 publications in Chinese literature.
• 4 compared to autograft (1 PT 3 HT)
12 LARS Papers
• Total 655 LARS grafts.
• Methodology – retrospective case series.
• Av. Age patients 21 – 46• Av. Time to surgery 7 months• Av. Follow up 28 months (4-60 months)
Reported Outcomes• Lachman grade
– 12% Grade II or more (60 of 499 grafts, 7 articles)
• Pivot shift– 5% grade II or more (20 of 515 grafts, 7 articles)
• 14 reported ruptures (2%)
• Lysholm Post op value of 82.8 – 98.7
• 1 case synovitis reported
Article YearJournal
Number Av Age Time to surgery
Av F/UMonths
1 Derricks 1995Operative techniques Sports
Medicine 220 33.4 30
2 Lavoie 2000 Knee 47 31.6 22
3 Duval ** 2002 JBJS 26 31 5 24
4 Qi S 2005 Chin J Min Inv Surg 16 33.7 19 4
5 Chen S ** 2007 Chin J Sports Med 23 28.2 2 15
6 Dong 2007 Chin J Orthop Trauma 21 35.7 1.5 9
7 Cerelli 2007 SIOT 25 46 10 60
8 Fan** 2008Zhongguo Xiu Fu Chong Jian
Wai Ke Za Zhi 15 18
9 Liu ** 2009 International Orthopaedics 28 36 8 49
10 Chen M 2009Chin J Reparative and Recon
Surgery 32 21 3.2 24
11 Gao 2010 Arthroscopy 159 30 5 50
12 Huang 2010 Chin Medical Journal 43 29
655 21-46 6.7 27.8
4 Comparison Papers
• No difference in the 10 outcome measures at final follow up (15 – 49 months).
• LARS patients reached full recovery sooner.
Correspondence Dr Nicolas Duval
• Best results are in early ACL repair augmented by LARS – Expect 80 to 90% good results at 10 years.
• Chronic ACL tear - 50% failure at 10 years
• Revision ACL surgery - 40% failure at 10 years.
Is there an optimal time to insert?
• acute injuries • good ACL stump • well vascularised
Tissue Ingrowth• 2 Papers • Yu – (Chinese) Rabbits
– If the stump was left - Connective tissue covering– at 6 months irregular collagen bundles with no
mature ligamentisation.
• Trieb– Invitro cellular ingrowth into LARS– Invivo – Ingrowth in a quads tendon.
Long Term Results LARS
Other PET grafts– Stryker Graft– Proflex– Lygeon– Leeds-Keio– ABC Surgicraft – Ligastic
Poor Results
• High failure rates
• Poor Outcome Scores (Lachman, Pivot, IKDC)
• Concerns regarding development of OA
Pittsburgh Group
Electron Microscopy
Conclusion• There is sparse and poor quality literature
• Early results of LARS good.
• Faster recovery but NOT BETTER than autograft.
• Concern based on previous PET grafts possibility late failure and iatrogenic OA
Recommendations
• Reporting and follow up is important.
• Randomised trials.
• Patients - informed of our knowledge of LARS.
• Need for ACL register?
Thankyou