Return to Duty in Initial Entry Training The Road to Recovery Following Anterior Cruciate Ligament (ACL) Reconstruction Surgery

The knee is the largest joint in the body and also one of the most frequently injured joints. Those engaging in athletic activities, such as those involved in military training, are particularly susceptible. The knee is inherently unstable due to its location at the end of the two longest bones in the body, the tibia and femur. Within the 194th Armored Brigade, partial or complete tears of the ACL accounted for 6 percent of total injuries in fiscal year 2007 and 10 percent of total injuries in fiscal year 2008. Sixty percent of soldiers who were diagnosed with ACL injuries in 2008 returned to duty. In 2007, ten percent of soldiers with ACL injuries successfully returned to duty. The ACL is the primary restraint to anterior tibial translation on the femur. Knee stability is maintained by static restraints (ligaments) and dynamic restraints (muscles). Mechanisms for injuring the ACL are varied and may occur with or without physical contact. Typically, the ACL is torn during a quick deceleration, rotational, or hyperextension injury that usually does not involve contact with another individual. Often the athlete lands on the leg and quickly pivots in the opposite direction. Injury is often accompanied by a “popping” sensation and depending on the mechanism of injury, may also involve injuries to the medial meniscus, as well as the medial collateral ligament (MCL). Non-operative management of an ACL tear is not a successful option for those participating in high levels of physical activities. Injury prevention is crucial due to potential surgery complications and low historical return-to-duty rates. Rehabilitation Injury to the ACL can result in recurrent instability, impairment, and progressive joint damage in individuals performing high-risk athletic activities. Reconstruction surgery is often indicated. ACL surgery is a complex procedure with many possible complications. Enabling a safe return to daily activities and preventing premature knee joint osteoarthritis requires carefully designed and appropriate rehabilitation strategies. Protocols for rehabilitation following ACL surgery have changed significantly during recent years. Exercises are becoming increasingly aggressive with the primary goal of returning the patient to the pre-injury activity level. Emphasis includes restoration of normal knee range of motion, strength, and stability to allow return to functional activities. Physical therapy is challenging as the patient and therapist must determine the correct balance between protecting the healing ligament, preventing excessive strain on the graft, and preventing disuse atrophy, as well as the negative changes in articular cartilage. The five phases of ACL rehabilitation and timelines include:  Activity maintenance (ongoing).  Maximum protection (12 weeks).  Moderate protection (24 weeks).  Minimum protection (48 weeks).  Return to activity (60 weeks). Return to Duty There is an absence of objective, standardized criteria that accurately and safely assesses a patient’s ability to progress through the stages of ACL rehabilitation and a safe return to sports. Advances in graft reconstruction and fixation techniques have consistently yielded good surgical outcomes, making it increasingly possible for patients to return to their previous function level. Although advances in ACL reconstruction surgical techniques and rehabilitation therapy have increased over the past 25 years, recent studies report that between 20 and 50 percent of athletes do not return to their pre-injury sports activities and 10 to 70 percent of those who return to pre-injury sports participate at a reduced level or with functional impairments. Anecdotal clinical observations and patient reports suggest the inability to return to pre-injury functional states may be partially attributed to fear of re-injuring the knee. Fear of re-injury has been associated with increased timeframes of returning to pre-injury function. There are also published case reports suggesting that return to high levels of competition and physical performance is possible in some instances. Success factors include, but are not limited to, optimal fitness prior to surgery, strong psychological deter- “Injury to the ACL can result in recurrent instability, impairment, and progressive joint damage in individuals performing high-risk athletic activities. Reconstruction surgery is often indicated. ACL surgery is a complex procedure with many possible complications. Enabling a safe return to daily activities and preventing premature knee joint osteoarthritis requires carefully designed and appropriate rehabilitation strategies.” Phases/Expected Timeline Rehab Guidelines Goals of the Phase Immediate Post-op – 1 week Continue passive motion Foot and ankle exercises Isometric hamstring exercises Inflammation control Quadriceps setting Weight bearing as tolerated Education Passive range of motion, 0-70 degrees Weeks 1-2 Progress weight bearing Ankle/hip exercises Modalities Range of motion Passive and active range of motion, 0-90 degrees Weeks 3-4 Progress range of motion/ Weight bearing Begin closed chain strengthening Stationary bike Active and passive range of motion, 0-100 degrees Weeks 5-6 Begin pool rehab Calf strengthening Full weight bearing Continue range of motion and close chain exercises Active and passive range of motion, 0-110 degrees Weeks 7-8 Continue as above Add treadmill Begin proprioceptive exercises Active and passive range of motion, 0-110 degrees Weeks 9-10 Continue as above Begin retro treadmill Progress closed kinetic chain Upgrade functional exercises Active and passive range of motion, 0-120 degrees Weeks 11-16 Continue as above Upgrade functional exercises Progress closed kinetic chain Active and passive range of motion, 0-130 degrees Weeks 16+ Continue range of motion, functional, and strengthening exercises Full active and passive range of motion, lower extremity strength near full Figure 1. Post-surgical ACL Rehabilitation Protocol 48 mination, an isolated ACL lesion, properly placed graft, and a personal progression of the volume and intensity of exercises mixing the gymnasium, pool, and field exercises. Recognition of deficits early in the rehabilitation process are important to notice as they will likely continue on to the later stages or rehab. Late ACL rehabilitation is considered to be a high-risk period, as perceived, versus actual sports readiness, which often varies. Although we lack objective criteria as to how or when an athlete can progress through the end stage of rehabilitation, criterion-based algorithms, not yet validated, are often used. A Soldier Success Story Private (PVT) Thompson, an 18-year-old male, entered the Army in July 2008 with military occupational specialty 88M. During his 6th week of initial entry training, he experienced a sudden deceleration injury while racing against another soldier. Following medical evaluation, he was diagnosed with a noncontact, full-thickness tear of his ACL with an associated bony contusion in the femoral notch and lateral tibial plateau regions. During scheduled surgery on 24 September 2008, PVT Thompson received ACL reconstruction surgery using a hamstring autograft. Following surgery, he was assigned to the Fort Knox Physical Training Rehabilitation Platoon (PTRP) where he underwent physical therapy three times weekly. During this time, his progress was periodically evaluated by his orthopedic surgeon and physical therapist. In December 2008, he was released to continue rehabilitation, independently, in the physical training rehabilitation platoon. PVT Thompson was cleared to return to duty late December 2008 and resumed military training in January 2009. Although ACL rehabilitation protocols vary in regards to return to athletic activities, it has been suggested in recent literature that return to pre-injury athletic activities should no longer be based purely on time restraints and should be individualized. PVT Thompson is an example of a soldier-athlete who successfully expedited return to daily activities and training. ACL Injury Prevention Programs Many factors have been proposed as potential causes of non-contact ACL injuries. These include, but are not limited to, “In the military, a soldier’s level of physical fitness directly impacts combat readiness. Ruptures of the ACL are common with an arduous course of rehabilitation required for full recovery. Our ability to understand ACL injuries, surgical procedures, and rehabilitation strategies have improved significantly over the past 25 years. Even with current technology, prevention and injury awareness remains the best strategy.” Andrews, J. R., et al., Physical Rehabilitation of the Injured Athlete, 3d Edition, Elsevier Inc., Philadelphia, PA, 2004, pp. 377-428. Brotzman, S. B., Handbook of Orthopedic Rehabilitation, Mosby Inc., Philadelphia, PA, 2003, pp. 183-258. Cerulli, G., et al., “Proprioceptive training and prevention of anterior cruciate ligament injuries in soccer,” J Orthop Sports Physical Therapy, March 2001. Frieden, et al., “Anterior Cruciate Insufficient Knees Treated with Physiotherapy,” Clinic Orthop, September 2001. Irrang, J. J. and Fitzgerald, G. K., “Rehabilitation of the Multiple-Ligament Injured Knee,” Clinical Sports Medicine, November 2000. King, S., et al., “The Anterior Cruciate Ligament, A Review of Recent Concepts,” J Orthop Sports Physical Therapy, August 1986. Mark, D. S., et al., “Traditional Versus Accelerated Rehabilitation Following ACL Reconstruction, A One-Year Follow-Up,” J Orthop Sports Physical Therapy, June 1992. Meyer, G. D., et al., “Rehabilitation After Anterior Cruciate Ligament Reconstruction: Criteria Based Progression Through the Return To Sport Phase,” J Orthop Sports Physical Therapy, June 2006. Starkey, C. and Ryan, J., Evaluation of Orthopedic and Athletic Injuries, Second Edition, FA Davis Company, Philadelphia, PA, 2002, pp. 187-241. Terese, L. C., et al., “The Association of Pain and Fear of Movement/Re-injury with Function during Anterior Cruciate Ligament Reconstruction Rehabilitation,” J Orthop Sports Physical Therapy, December 2008.

a lack of control in inward and outward muscle forces crossing the knee, hamstring weakness, delay in hamstring activation, decreased co-contraction of the quadriceps and hamstrings, muscle fatigue, reduced gastrocnemius strength or recruitment, and reduced efficiency of ankle and hip balance strategies. In the military, a soldier’s level of physical fitness directly impacts combat readiness. Ruptures of the ACL are common with an arduous course of rehabilitation required for full recovery. Our ability to understand ACL injuries, surgical procedures, and rehabilitation strategies have improved significantly over the past 25 years. Even with current technology, prevention and injury awareness remains the best strategy. Rehabilitation from ACL reconstruction surgery varies from 6 to 12 months, having a significant impact on the fighting force. ACL injury prevention strategies include well-balanced phys ical training programs, sports education, risk management, and bracing. Incorporating injury prevention education into physical training programs is recommended and advantageous. Captain Melissa Ogle is currently serving as commander, B Company, Physical Training Rehabilitation Platoon, 46th Adjutant General Battalion, 194th Armored Brigade, Fort Knox, KY. She received a B. S., a Master of Physical Therapy (MPT), and a Doctor of Physical Therapy (DPT) from East Tennessee University. Her military education includes Airborne School, AMEDD Officer Basic Course, and AMEDD Officer Advanced Course. She has served in various command and staff positions, to include chief of physical therapy, 31st Combat Support Hospital, Iraq; and physical therapist, General Leonard Wood Army Community Hospital, Fort Leonard Wood, MO. 49