Return to Play After an Anterior Cruciate Ligament Injury: Prioritizing Neurological and Psychological Factors of the Decision-Making Algorithm

The final segment of the CNS neuromotor rehabilitation program is the “lower quarter dynamic agility phase” (Table 1), when the player will learn to perform an unanticipated directional change in a foundational position for the pivot leg. The player can begin this phase by initiating sprint-deceleration-pivot efforts, progressing at 45°, 90°, 120°, and 180° turns. This should be trained in both a forward and backpedal position. Close attention should be paid to the deceleration phase of the sprint-pivot effort, as this will set the player up to demonstrate protective kinematics during the pivot phase of the task. In this phase, the center of mass should become lower and move posteriorly, so that a deeper knee and hip flexion angle, supported by posterior chain synergies, can occur at the pivot point. This is an important skill for the player to acquire, as Cortes and colleagues⁹² have reported that female collegiate soccer players tend to perform a pivoting task with a more erect trunk position. In the same cohort, they also measured the mean knee flexion angle at initial contact during pivoting to be 24°.⁹² Movement patterns that reflect an elevated center of mass, with arms abducted away from the trunk, should be discouraged here. The drills can be progressed to have the player react to a command and perform unanticipated pivots within a 5 × 5-meter box to simulate defending. This should be progressed from eyes open and arms unconstrained, to vision disrupted and arms constrained. From here, an external focus of control can be added by playing a ball to the athlete. Vision should be withheld until the instant that the ball arrives at the player, when he/she is required to play the ball to an unanticipated spot. As is the case in all other phases of the neuromotor training, the quality of movement is the most important parameter to critique with each drill. From a qualitative standpoint, the player should demonstrate stiffness throughout the thoracolumbar region and power and control through the pelvis with each directional change. In addition, he or she should maintain a low and posteriorly oriented center of mass to optimize leverage in the hamstrings/gluteals compared with the quadriceps and reduce posterior ground reaction forces.

PSYCHOLOGICAL READINESS FOR RETURN TO PLAY

After an injury is sustained, an athlete is often subjected to a range of psychological responses in addition to the functional impairment, including stress, hesitancy, alterations in self-esteem, depression, fear of re-injury, and anxiety.^43,109-111 The aforementioned responses are often at their height in the time immediately following an injury and generally subside over time during the rehabilitation process.¹¹⁰ The rates at which athletes experience psychological distress following an injury range between 5% and 19%; the levels are comparable with patients receiving treatment for mental health illness.⁴³ However, these elements may persist, or even increase, in the later stages of the rehabilitation process as the topic of return to play is deliberated.^112,113 If these fears are left unresolved, then a significant delay can be incurred during the rehabilitation process, which might ultimately jeopardize the successful return to play.^114,115

When athletes have been cleared to return to sport, fear tends to be the most common reason for their decision to not return to play.^21,116 The persistence of fear has clinical implications and warrants close monitoring to ensure that the athlete feels adequately supported in the decision to return to sport.^117,118 Building the athlete’s confidence by addressing hesitation, lack of confidence, heightened awareness of risk or re-injury, and safe reintegration into athletic participation are important themes identified to encourage a safe return to play.⁴³ A variety of validated tools  can be integrated into an existing return-to-play decision-making algorithm (Table 2).^118-120 

Abbreviations: ACL, anterior cruciate ligament; CNS, central nervous system; CIMT, constraint-induced movement therapy.

Table 2. Self-Report Measurement Tools to Integrate into Return-to-Play Decision-Making Algorithm

By integrating the necessary screening of patients for kinesiophobia and assessing patient expectations after enduring an ACL injury, clinicians may be able to identify patients who are at risk for poorer functional outcomes. A consideration of psychosocial elements such as activity avoidance, fear of movement and re-injury, loss of confidence and expectations/assumptions during the continuum of the rehabilitation process, and the decision to return to play may favorably impact the individual’s ability to safely return to sport. It is critical to address both the physical and psychosocial factors during the rehabilitation process to more optimally transition individuals back to their prior level of athleticism.

CONCLUSION

Psychosocial factors may play a role in determining a player’s readiness to return to sport, as well as a potential for re-injury. A number of tests are available for use with this patient population to identify mental deficits that may impact player performance upon return. Additionally, the CNS should be considered as a source of impairment in players with ACL injuries. Current protocols may not fully appreciate the CNS’ impact on the player’s functional outcome. Therefore, an approach that includes CNS neuromotor training with traditional musculoskeletal rehabilitation, which also incorporates cognitive and psychosocial factors, may define an improved paradigm for treating soccer athletes following an ACL injury and assessing return-to-play capability.