Damage of the anterior cruciate ligament in the knee is one of the most common serious injuries in young athletes and, reflecting individual activity, is habitually treated surgically. ACL reconstruction, the gold standard, requires the harvesting of a hamstring or patella tendon graft, which is used as scaffold for new ACL growth. Cadaveric ligament harvesting and transplant is promising, though autologos (own) tissue graft placement is still proffered owing to the reduced risk of graft failure and tissue rejection.
Soft tissue graft harvesting for ACL reconstruction is the current choice amongst surgeons due to the relatively straight forward procedure and recovery seen. However more recent studies have concluded that the patella tendon graft is superior. The shift in muscle dominance required of an ACL vulnerable knee, means hamstring harvesting may be counterproductive. Increase in hamstring strength is crucial to reduce impact within the joint.
Recent studies of ACL injuries comparing patients that opt to delay surgery for early rehabilitation with those that have early surgical intervention and subsequent physiotherapy, show that from the time of operative intervention a similar recovery and success rate is achieved. However those patients that delay treatment demonstrate a higher rate of meniscus damage, suggesting some in this group may have benefitted from immediate intervention. Nonetheless, close to half of those who delay surgery never opt for surgical intervention, with many showing partial to full recovery. Although these assertion may seem to favour no surgical intervention, accept in the extreme of cases, this may not be the case; prognosis is fundamentally an art of intuition.
Physiotherapy therefore remains the key figure in successful rehabilitation with patient education of the utmost importance. Dynamic intervention is paramount; dips in physical fitness promote stiffness and loss in range of motion as well as increased load bearing in the joint, whilst over activity promote relapse. Maintained physical activity inclusive of the knee joint promotes maintenance of tissue integrity and supports repair of damaged tissue conceivably as a result of increased vascularisation. A physiotherapy program built on eccentric exercises focusing on increasing lower body strength to a degree greater than before damage is vital to successful recovery and maintenance of strength is symptomatic of long term stability.
Novel methods for ACL repair are focusing on promoting the body’s own regenerative ability. One such method, aptly named the Healing Response Technique has been used by athletes for the best part of the last decade yielding a superior response, yet formal evaluation seems to be primarily in the clinical testing stage. Kohl and colleagues from the University of Bern and the University of Zurich utilising sheep models (2012) boast:
“The dynamic intraligamentary stabilization technique successfully induced self-healing of ruptured ACL in a sheep model. Knee joints remained stable during the healing period allowing free range of motion and full weight bearing, and no signs of osteoarthritis or other intraarticular damage in the follow up were observed.”
As an individual having come through ACL reconstruction, a partial (50%) menisectomy and with an ACL revision on the cards, I can only emphasise the importance of educating patients, reinforcing the function of physiotherapy and the benefits of maintaining physical activity. There is indeed a call for public funding and investment for non invasive therapy.
Images reproduced from orthopedics.about.com, muscleprodigy.com and buzzle.com