Post Title
Anterior cruciate ligament (ACL) injury is a catastrophic injury to the structural scaffold of the tibiofemoral joint (thigh and lower leg bone joint) whereby the forces tolerated by anterior cruciate ligament are exceeded resulting in break-down of the ligament tissue either partially or completely (rupture). No two ACL injuries are the same with concomitant injuries common including meniscus tear, bone marrow oedema (BMO), other collateral ligament tearing (MCL/LCL/PCL) and chondral cartilage injury (tissue covering articulating surfaces of the knee joints).
Mechanism behind injury of ACL is 70-80% of the time non-contact, whereby the individual is typically landing from a jump, pivoting or decelerating (Renstrom et al, 2008). ACL injuries resultant from contact typically occur with a blow from behind the knee causing a forward shearing force at the knee.
Despite the overwhelming research in the ACL space over the past 20 years incidence rates continue to rise with Australia’s ACL incidence rate the highest in the world (Moses and Orchard, 2012) with annual growth rate of 4-8% each year in males and 5-10% each year in females. Highest rates of ACL injury occur within those sports whereby movement patterns include frequent pivoting/cutting.
Return to sport rates post ACL injury vary significantly throughout research and are dependent on many differing variables external to the injury itself. Despite high return to sport levels post injury less than 50% return to their previous level of competitive sport and only ~63% return to there pre-injury sport (Arden et al, 2011, 2012). Statistics highlight that those returning to sport 1 in 5 will re-injure within the first 10 years with 50% of these injuries occurring within the first year alone (Shelbourne et al, 2009). 1 in 3 individuals under the age of 20 years that return to sport will sustain a second ACL injury within the first 2 years with greatest risk within the first year post operation (Nagelli and Hewitt, 2016). For every month that return to sport timelines were delayed until 9 months the rate of knee re-injury is reduced by 51% (Grindem, 2016).
Not only is allowing time for biological healing a critical piece to effective ACL rehabilitation prior to returning to sport. Also, as critical is following up with your physiotherapist to assist and guide you through the initial process of calming down the knee from a swelling and pain perspective early on post injury/surgery and regaining function including full knee movement regaining lower limb strength and returning to a normalised walking pattern. Through to returning to a fluent running style, re-gaining adequate neuromuscular control, power and agility prior to returning to sport ensuring the individual has achieved the necessary prerequisites unique to the demands of their specific sport.
Research evaluating return to sport post ACL repair at 12 months demonstrated only 23% of patients who have returned to sport met all criteria required to pass the recommended physical performance battery prior returning to sport, likely elevating and contributing the risk and level for re-injury rates (Edward et al, 2018). Post-operative rehabilitation has a significant association with greater physical function, most evident in younger patients and is a critical component to restoring physical function necessary to withstand the demands required to not only return to sport but return to the same sport at the same competitive standard. This alarming statistic raises questions regarding can re-injury rates partially be attributed to level of therapist understanding with respect to physical function qualities required to return sport or quality of education provided to patients around those conversations regarding level of physical function necessary to pass the criteria developed to lower potential re-injury rates particularly within the first 2 years upon return to sport. Furthermore, does the therapist have the necessary access to utilise technology required to effectively measure and assess such critical qualities including strength, power and movement patterns before providing clearance for return to sport.
