Standardized Sports Testing - Have We Standardized Anything Yet? - A Guest Blog

This week's blog series comes to us by Eric Dinkins, PT, MS, OCS, Cert MT, MCTA.  Besides the plethora of designations behind his name, Eric is a fantastic physical therapist practicing out of Colorado.  Eric has a huge passion for education and is Mulligan Certified Instructor and teaches physical therapist all over the US.  I first came across Eric ~5 years ago after he had developed a technology called motion guidance.  This simple, inexpensive and very effective training device I have used in my practice and courses ever since.  I was blessed to come across Eric and learn from him.  So when it came to retraining human movement, including Eric in this series of guest blogs was a no brainer. 


Please sit back and enjoy as Eric provides us the latest. - Sincerely ~ Trent Nessler, PT, MPT, DPT

This is a 3-part blog series on the topic of Return to Play (RTP) in ACL reconstruction clients.  The goal is to provide information about the current RTP testing, potential mechanisms that are involved, and options for improving outcomes. Sports performance, in regard to prevention and return to participation, is a common part of any orthopedic practice. It deals with athletes of all levels; from the elite competitor to the weekend warrior, to the client who wants to return to tennis after a Total Knee Arthroplasty.  According to the recent recommendation published in 2016 by the British Journal of Sports Medicine, Rehabilitation after ACL injury should include a prehabilitation phase and 3 criterion-based postoperative phases: (1) impairment-based, (2) sport-specific training and (3) return to play. A battery of strength and hop tests, quality of movement and psychological tests should be used to guide progression from one rehabilitation stage to the next. Postoperative rehabilitation should continue for 9–12 months. To assess readiness to return to play and the risk for re-injury, a test battery, including strength tests, hop tests and measurement of movement quality, should be used.

Training or rehabilitation often focuses on strengthening and motor control re-education to correct faulty movement patterns, imbalances and asymmetries.  In virtually every case, functional sports testing is performed to determine if the person is ready to return to sport, and if they are at risk for re-injury. So, what happens when the tests that we use to conclusively decide if a person is ready differ so greatly in the published literature?  Why the battery of tests when we’ve been performing return to play testing for years? One answer came when Hegedus BJSM 2015 reviewed some of the most common tests used in physical performance testing and found an extremely wide variance in several aspects of the tests reviewed.  

Some of these tests included what some consider “gold standards” for return to sports play.                

Tests include: Single leg hop for distance, 6 M timed hop, cross over hop for distance, single leg squat, triple jump, and single leg vertical jump.  What Hegedus found, was that there is a variance in the procedures in which they are applied.  The warm-up and number of practice hops, number of hops recorded in the test, how the arms are used, and final scoring can be based on mean of attempts, greatest of attempts, and greatest of successful trials.  So, if we can’t rely on standardized testing that has poor reliability at the present time, the importance of movement analysis and motor control becomes magnified!

Often testing against the non-involved leg makes the assumption that the uninvolved side avoided injury because it was the stronger or more stable side…an assumption that has been proven false by far too many people who have torn ACL’s in both knees. Both sides of this story can be found in journals such as this…this, and this.

                                                                                             

Also, joint forces and other additional elements play a role in ACL or knee injuries, therefore, focusing solely on lower limb kinematics in classifying injury risk or post-injury rehab may not encapsulate all relevant factors.  Even attempting to examine “normal” in the attempt to standardize kinetic motions for populations and translate that data into risk factors has come up short in developing a predictability rule of sorts for determining return to participation (Fox, Sports Med 2014)

This comparison suggests that at the time of testing, athletes, regardless of being cleared for return to sport, were deficient in dynamic control and therefore at risk of injury.  Furthermore, asymmetries across both groups suggest that these deficiencies likely existed before the initial ACL rupture and may have been associated with the initial injury. Routine examination or sports testing of the lower limb may not pick up on neuromotor control deficits that may be compensated for and missed during clinical evaluation but may be contributing to abnormal movement patterns increasing the re-injury risk. Clinical impairment measures do not appear to be related to measured functional ability. Performance of both functional tests, FMS, and YBT-LQ at 6 months would suggest that the typical patient in both groups would be at a greater risk of lower extremity injury (AJSM 2015).

Also, quadriceps ECC strength was more directly correlated to JPS than concentric strength in patients with PFPS. This suggests inhibition or weakness of the type II muscle fibers that are responsible for maintaining the eccentric muscle force during movement.  The link can be made between quadriceps ECC strength, proprioception and pain in this population (Knee Surg Sports 2015). But simply improving strength neither guarantees non-injury or addresses other factors that could contribute to injury occurring. Video replay and/or video analysis has shown some promise to help aide athletes to improve their joint positional sense. But, video replay lacks the immediate visual feedback that has been proven to enhance motor learning skill acquisition.

There are numerous expert clinicians in the field of sports rehabilitation capable of skillfully attempting to determine when a patient or athlete is ready to return to dynamic function, and often times the individual is able to return without future injury.  I have spoken with colleagues whose preferences range from using the ECC step down testing to return an OL in college football to play, to using a barrage of physical performance tests to acquire as much information as possible to make the determination. However, what about the clinician who is deemed with the task of determining a patient’s suitability to return to participation without the expert knowledge base?  Surely, they cannot rely on functional based sport testing for the lower extremity.  So, what resources can they rely on?  Unfortunately, the most realistic answer is devoting the time to become an educated clinician, and skilled movement analyst.  The maximum amount of information must be acquired to help determine when someone is ready to return to participation.  NOT solely relying on the hard numbers and pass criteria that are suggested in sports testing models.  Use all resources that are available to you such as sports psychology assessments, visual feedback training with the Motion Guidance system to help the patient better understand what actions may be occurring during actions in real-time feedback and help the clinician get sport specific information during those actions, and consider need for extra motor learning as well as strength and conditioning.  For example, watch this video and see how simple bilateral jump testing with visual feedback and yield valuable information about potential fatigue, form, and dynamic actions around the lower chain.

I took this information, shared it with my client, and it really hit home the training areas that she needed to focus on despite “feeling” really good at the time of testing.

It has been suggested that advancing patients through the stages of motor learning and eventually giving external cues for function will facilitate transfer of motor control to subcortical regions of the brain and free cortical resources from programming more complex actions.  Incorporating visual-motor control training into rehabilitation may decrease the reliance of visual feedback to make dynamic changes in muscle function during an open environment (JOSPT 2015).  These factors make the safe return to participation tough. A grey area instead of black and white.

The take home message? Each of these considerations must be individually applied to each individual case in order to continue to decrease the risk of injury after return to play.

Thank you.

Eric M. Dinkins, PT, MSPT, OCS, Cert MT, MCTA

Dr. Nessler is a practicing physical therapist with over 20 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment.  He is the developer of an athletic biomechanical analysis, is an author of a college textbook on this subject  and has performed >5000 athletic movement assessments.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Chairman of Medical Services for the International Obstacle Racing Federation and associate editor of the International Journal of Athletic Therapy and Training.   He is also a competitive athlete in Jiu Jitsu.