ACL reconstruction is a big deal, and anyone who’s actually had ACL surgery will be able to testify to that. One of the issues with ACL reconstruction is the time that’s required after the surgery before the patient is able to go back to sport safely. A large part of this is about the rehab, and it’s vital that the patient does not return to high-demand high-risk activities until they have regained sufficient muscle bulk and power plus fast enough reflexes to regain dynamic stability, to protect the graft. However, another major element is the issue of graft remodelling.
Whether one uses a donor tendon graft (an allograft) or whether one takes some of the patient’s own tendon tissue (from the hamstrings or from the patellar tendon), either way, as soon as a tendon is detached from its blood supply the cells in the tendon die. From that point onwards there is a progressive weakening of the graft due to microfractures in the collagen fibres within the tendon tissue. Once a graft is implanted, it starts to regrow a new blood supply from the top and from the bottom. The blood vessels seed the new ligament with living cells, and the cells then start to repair the collagen fibres, which is called ‘remodelling’. Importantly, it can, however, take up to 2 years for a graft to remodel fully – and until this has happened, the graft is therefore weaker and thus at increased risk of potential failure (stretching or actual rupture). Therefore, anything that speeds up graft remodelling is a positive, as this has the propensity to reduce the risk of ACL graft rupture, and it also means that it might be safer to return to sport sooner.
One other potential issue with ACL surgery is that sometimes the bone tunnels may end up widening, which can be associated with bone loss, a poorer ‘fix’ of the graft and possible cyst formation. Therefore, anything that potentially decreases tunnel widening should also be welcomed.
Torn ACL (avulsion of the ligament off its femoral attachment).
ACL reconstructed with graft (a tendon allograft).
Since 2014 I have been using Vivostat PRF (platelet-rich fibrin) autologous biological glue for various uses within the knee, including fixation of articular cartilage grafts in the knee, biological augmentation of meniscal repairs and meniscal transplantation, and also as a fibrin sealant to reduce bleeding, pain and swelling after knee replacement surgery. In 2017 we extended the use of Vivostat PRF to include ACL surgery too.
Vivostat PRF has been in use for years in specialties such as Cardiothoracics, Plastics and Hepatobiliary Surgery, mainly as a sealant to prevent vascular or biliary leakage, but also to promote healing. 120ml of blood is taken from the patient’s arm in the anaesthetic room, immediately ahead of the surgery. This is then spun down to provide approximately 5ml of PRF. Importantly, this is not ‘PRP’ (platelet-rich plasma) – this is autologous platelet-rich fibrin (PRF), which is like the sticky part of a blood clot mixed in with a high concentration of unactivated platelets. The fibrin acts like a glue / sealant, whilst the platelets release growth factors over the course of the first 7 days or so. The PRF is just gradually absorbed with time, over the course of the first week or two. There is evidence that Vivostat PRF improves outcomes after knee replacement surgery (personal data, presented at the Orthopaedic Product News Knee Conference, Leeds, Nov 2019) and that ‘biological augmentation’ of meniscal repairs also improves meniscal healing rates.
A recent publication in the The Orthopaedic Journal of Sports Medicine has reported the results of the first formal study looking at the use of Vivostat PRF in ACL surgery:
Does the application of platelet-rich fibrin in anterior cruciate ligament reconstruction enhance graft healing and maturation? A comparative MRI study of 44 cases.
Beyzadeoglu T, Pehlivanoglu T, Yildirim K, Buldu H, Tandogan R, Tuzun U.
The Orthopaedic Journal of Sports Medicine
First published Feb 20, 2020: https://doi.org/10.1177/2325967120902013
This research was undertaken by Professor Tahsin Beyzadeoglu, who is one of the leading Knee Surgeons in Turkey. This observational case-controlled cohort study looked at 44 patients having ACL reconstructions with hamstring autografts, with half having the graft sprayed with Vivostat PRF at the end of the procedure and half not. The patients were assessed post-operatively with MRI at the 5-month post-op point. In this study, the application of PRF to the ACL graft was shown to lead to superior graft integration and maturation in the proximal third of the graft, with a more normal signal intensity in the proximal graft and with less synovial fluid seen around the graft-tunnel interface. In addition, there were significantly fewer cases of post-operative haemarthrosis seen in the Vivostat PRF group.
ACL reconstructed with graft (a tendon allograft).
ACL graft sprayed with Vivostat PRF.
In my practice, I routinely use Vivostat PRF with my ACL reconstructions. I spray the PRF up the distal end of the femoral tunnel, over the front and around the back of the intra-articular portion of the graft, and also copiously around the distal end of the tibial tunnel too. This is a cheap, safe, autologous method of reducing post-op bleeding, swelling and pain, and improving the biological healing of grafts. It is through the adoption of multiple techniques, each offering a degree of benefit, that collectively, we achieve a large improvement in our patient outcomes, and in our practice we continue to be at the forefront of cutting-edge techniques and gold-standard care.
CLICK HERE for further information about the use of Vivostat PRF in knee surgery.