Abstracts
In vivo and in vitro cellular ingrowth into a new generation of artificial ligaments
Although the new generation of artificial ligaments are showing encouraging clinical results in contrast to earlier generations, studies on the biological properties are lacking. Biopsies were taken from a LARS, six months post implantation and investigated by histochemistry. An in vitro study seeding human fibroblasts or osteoblast–like cells (up to 106 cells for 21 days) on ligament pieces (5 x 5mm) was concluded and analysed. The biopsies showed complete cellular and connective tissue ingrowth in the LARS. In vitro fibreblasts and osteoblast–like cells encapsulated the fibres by bending a cellular net around them. This mechanism might explain the strength and inert behaviour of the ligament without the synovitus associated with previous artificial ligaments.
In vivo and in vitro cellular ingrowth into a new generation of artificial ligaments
K Trieb, H Blahovec, G Brand, M Sabeti, M Doninkus, R Kotz
Eur Surg Res 2004; 36:148 – 151
Repair of achilles tendon with a LARS
According to the five cases reported, the use of the LARS ligament for achilles tendon repair seems promising, allowing early range of motion and weight bearing with overall excellent function and return to activities.
Fletcher Dural Guern Cardinal
1st Symposium of Biomaterial Advances. (Montreal, Canada 1997)
Patient satisfaction needs as related to knee stability and objective findings after ACL reconstruction using the LARS
The purposes of this study are to compare patient satisfaction with the objective measurement of knee stability and assess early complications following ACL reconstruction using a LARS. 47 patients were reviewed 8–45 months after surgery. The LARS may be a safe device to reconstruct an ACL tear.
Lavoie, Fletcher, Duval (Montreal, Canada)
The Knee (2000) 157 – 163
Posterior Cruciate Ligament Reconstruction: The Role of Synthetic Ligaments
The treatment of acute PCL's are possible, logical and will be identified in the future. As for chronics, the results which were not as promising were «probably the cause of the failure is the complexity of the lesions in which the differential tensions at the artificial ligament are next to impossible to adjust».
28 cases of PCL reported between 1993 – 1999 15 chronic, 13 acute
Teule
Riv Lt Biol Med 20 2000
Outcome of 19 patients with combined ACL and PCL injuries
Early surgical repair with prosthetic ligaments allows early mobilisation of the knee joint, improving stiffness, and favours the anatomic cicatrisation of the peripheral structures. Considering how severe the trauma was and the relevant lesions of the surveyed cases, the treatment was validated.
New Zealand Orthopaedic Association 3 – 6 October 1999 (Wellington)
A new generation of artificial ligaments in reconstruction of the ACL. A Two year follow up of a randomised trial bone patella bone in 27 patients vs LARS in 26 patients. Assessment before and at 2, 6, 12, 24 months after surgery
There were no cases of synovitus or of infection of the knee. There was no difference regarding the failure rate of the groups. The IKDC showed no significant differences between the two groups at any stage of the follow up. The KOOS evaluation showed consistently higher results in all subscales for the LARS group during the first year of follow up.
After 24 months these differences were no longer evident. Our findings suggest that at follow up at 24 months the LARS seems to be a satisfactory treatment option, especially when an early return to high levels of activity is demanded.
Nav, Lavoie, Duval (Montreal, Canada)
JBJS (UK) 2002 – 356-60
10 year follow up of Acute PCL repair
It was concluded that the use of proper synthetic ligaments as an internal fixation to immediately recenter the knee, seems a good solution for PCL injuries. Postero lateral injuries must be diagnosed and treated simultaneously. The healing potential of the PCL and postero lateral structures avoids harvesting autografts. Recentering the knee while full motion and exercises are permitted, with a simple arthroscopic procedure seems to allow a perfect healing of the torn PCL without elongation and with the preservation of proprioception. This often results in practically normal knees with no degenerative changes. Maybe we should consider now to operate on acute PCL in young and active patients instead of staying in the classical, wait and see, attitude.
Laboureau
SICOT Meeting – San Diego 2002
The 'Y' ligament in Combined PCL and PLC Injuries
126 patients – the external rotation had markedly reduced and good stability was restored following this reconstruction.
Beacon, Laboureau, Ravikumar
Biomaterial Advances – 1997 (Canada)
Posterior Cruciate Ligament Injuries
Considering the risk of severe degenerative changes in non-operated PCL injuries and considering the results that we are able to obtain now, it seems logical to operate on them. Our study suggests that PCL injuries in young and active patients should be operated acutely, where the results appear to be even better than for the ACL, for which surgery is widely accepted. The frequency and the importance of a combined postero lateral instiblity must lead us to think about it. The concept of early 'ligament synthesis' using synthetic ligaments which have proven their excellent tolerance and efficacy is now the procedure of first choice for many knee surgeons.
A practical guide to management
Johnson & Laboureau
Spinger Publications
ACL Arthroscopic Reconstruction with Lars - 220 ACL's 1997 – 2000
We believe that the future belongs to the synthetic grafts. Lars does not create any damage to the already injured knee and is the ideal graft today for ACL injuries in acute cases and in chronics with the presence of well vascularised stump.
Maheras, Alexakis<
Poster 4th Seminar in Arthroscopic Surgery & Sports Medicine – June 2000
Biomechanical Analysis of Different Operative Techniques with complete ACJ disruption
The goal of this study was to evaluate three different operative techniques for acromioclavicular joint fixation: trans-articular K-wire fixation; ligament reconstruction along with a synthetic augmentation device (LARS); and coracoclavicular Bosworth screw. Mechanical properties were tested in a cadaver study in order to determine the primary mechanical stability during repetitive passive motions. Eighteen fresh cadavers were used to test a cyclic load (50,000 cycles). Secondary joint dislocation and the rate of implant loosening were monitored by standard AP stress X-ray. Metal markers in the coracoid, the acromion and the lateral clavicle were used to measure the acromioclavicular distance increase (?-AC) and the coracoclavicular distance increase (-CC). The range of motion was set on 30° – 90° of abduction for the first 25,000 cycles and then was raised to 60° – 120°.
The least amount of vertical dislocation was seen in the K-wire and the LARS group (mean ?-CC 0.3mm; range: 0 – 13mm and 1.5mm; range 0 – 67mm, respectively). The Bosworth group showed significantly higher dislocation rates (4.2mm; range 2.3 – 7.1mm; p – 0.005). This was true especially when the abduction range was extended to a maximum of 120°. The rate of implant loosening in the K-wire group was higher than that in the other two groups. This study shows that the LARS procedure and the K-wires technique give equal results concerning stability after repetitive passive motion but with a high rate of implant loosening in the K-wire group. According to our findings, abduction should be limited to 90° after implanting a Bosworth screw in order to prevent loosening or failure of the hardware.
Krenn
Osteo Trauma Care 2005 – 154 – 159
The use of the Free Fibres in Acute ACL Repairs - 219 patients, follow up 1 – 5 years
LARS allows a purely arthroscopic technique which respects proprioception. It is a conservative approach since the tunnels drilled are small. The results are at least comparable to other techniques but simpler and faster for the patient.
Post operative arthroscopic and histological controls showed that the LARS were well tolerated and invaded by fibrous tissue while the torn ACL was perfectly healed when the injury was located at the upper or lower extremity but not so well for mid substance injuries.
Laboureau
Biomaterial Advances – 1997 (Canada)
Postero Lateral Corners
The use of synthetic graft allows immediate reconstruction for whatever the number of ligaments involved. We had no complications due to the synthetic ligaments. This technique can be recommended when PLC is combined with PCL or ACL reconstruction.
PLC – follow up 1 – 7 years
Laboureau
Abstract from the European Trauma Congress – 2002 (Vienna)
Traumatic ACJ separation. Current concept
LARS has offered the option of early postoperative functional treatment, especially in cases of biodegradable devices there is no need for a secondary operation.
Fialka, Stampf
European Surgery Journal - 2004 20 – 24 (Vienna, Austria)
Preliminary results in ACJ dislocation using a LARS
The use of an augmentation device (LARS) in addition to ligament reconstruction after ACJ separation seems to give satisfactory early functional results. This technique can be recommended regarding the possibility of early postoperative functional rehabilitation.
Fialka
Poster - ESSKA 2000 (Vienna)
Our experience with LARS in massive rotator cuff tear, 44 cases
This poster discusses different surgical approaches for LARS in the RC application, including a modified osteotomy of the acromion in an anterior-lateral approach to decrease complication. Good results for reinforcement (18) and replacement of the RC for massive (11) and large (15) tears.
Ramon, Alonso, Nistal
Poster
European Congress of Sport Traumatology - 2003 (Monaco)
Permanent tendon replacement for RC defect. Nonsense, alternative or a solution? 33 patients, 2 months – 3.5 years, average age 57.6
No post operative complications. Time in hospital was four days. The Constant score and ASES index reflected clear improvements.
LARS rectifies chronic, primary, non-closable rotator sheath defects in terms of pain relief and usability. It meets doctor and patient expectations. It offers a simple solution to a serious problem.
Kienn, Friesach
Jatros Orthopaedics 2005, 11 – 13
Comparison of two methods – over the top and trans-osseous – for augmented reconstruction of the supraspinatus tendon in terms of abduction movement arms
LARS RC 30 patch was used on 14 cadaveric shoulders. The LARS patches were fixed to a type A or B method. The difference between these A and B methods was the re-insertion point.
A was done trans–osseous in the anatomical neck e.g. the solcos at the edge of the greater tuberosity. B is an over the top procedure, the LARS is bent over the greater tuberosity and fixed trans-osseous at the surgical neck, e.g. latero-caudal of the greater tuberosity. Each used a 7mm drill hole with a 7 x 30mm LARS screw. No sutures ruptured, no defect was found in the LARS patch after the test, the screws did not loosen.
The X-rays showed a 10.6% difference in lower arm conditions comparing A to B. Type A is recommended for normal muscle conditions and for when the augmentation acts as a spacer between the humeral head and the acromion, this fixation prevents more impingement. In cases with weak muscle conditions and combined with an acromioplastic procedure, the over the top technique B can give the muscle about 25% more efficiency. The lateral insertion makes it easier to lift the arm and has an advantage especially in chronic defects with muscle degeneration.
University of Vienna – 2005
Bone & Joint Biomechanical Laboratory
A Novel use for Synthetic Ligaments in Hip Surgery.
A bare trochanter is a lesion similar in pathology to a rotator-cuff tear in the shoulder and is occasionally seen during an anterolateral approach to the hip. Small defects can be repaired by suturing the abductors onto the bare area, but larger defects require a different strategy. Similar defects can be found after posterior approaches to the hip particularly at the time of revision surgery. We describe the novel use of a synthetic ligament to reconstruct these defects.
Dynamically reconstructing damaged muscles following hip surgery can be achieved successfully with synthetic ligaments which have inherent strength whilst acting as a scaffold into which native tissue can grow. Previously described repairs have been static tethers with an inherent hard end point to movement making the dynamic technique described an attractive proposition.
B Holroyd, DE Fern.
Trauma and Orthopaedic Department, Royal Cornwall Hospital, Truro, Cornwall.
Annals Royal Collage of Surgery English 2008.90:253-259
Knee section
ACL reconstruction, using artificial Ligament, 5 years follow upConclusion:
Based on the results of our study with a five years follow-up and on the data of the International Literature, we can say that the new generation of LARS® artificial ligament used as graft in the ACL reconstruction is an «happy reality», although actually the choice of the patients are selective. The five years follow-up, in our opinion, is a sufficient period to judge the results, as scientifically» valid. We did not experience the bad complications of the 80's; no one of the patients had significant swelling of the knee as signs of chronic post-op synovitis, and the objective and subjective results were positive in over 95%. However the positive evaluation from the neutral examiner observer is another positive result on the final evaluation. From the 25 cases tested, only one of them had bad results, based on the clinical and instrumental evaluation, which showed residual knee instability. It is important to point it out the results in using the biological graft as autograft or allograft are the same or even worse.G Cerulli et al.
S.I.C.O.T. 2007;33(suppl.1) : S238-S242