Date: 12/18/02
Author: Keegan McConnell, PT, Physical Therapy of Flower Mound, TX

Related Items:
The ACL Experience - Part I - Injury and MRI
The ACL Experience - Part II - MRI Results and Surgery Prep
The ACL Experience - Part III - Surgery
The ACL Experience - Part V - Knee Brace and Last Doc Visit
The ACL Experience - Part VI - Guess Who's Back Wakeboarding

Patients who undergo an anterior cruciate ligament (ACL) reconstruction generally present for their outpatient physical therapy initial evaluation three to five days post-operatively, depending on physician preference. Initiating the rehabilitation process soon after surgery prevents running into roadblocks later in the rehabilitation process and assists in achieving timeline goals.

There are four phases that can be applied to the rehabilitation process. They are the (1) mobility, (2) stability, (3) controlled mobility, and (4) skill phases. Each phase defines the goals of that stage of rehabilitation. These phases are not mutually exclusive. Most patients are working in more than one phase at a time as they progress.

In applying this process to Marty's rehabilitation program, mobility refers to obtaining adequate range of motion in his knee to move through the motions required for wakeboarding (i.e. bending, squatting, jumping). Stability refers to having enough strength in his leg to maintain support of his body weight while standing on the wakeboard. Controlled mobility refers to successfully performing movements in a controlled manner on the wakeboard without losing balance (i.e. squat). Skill refers to the ability to return to full wakeboarding and perform all tricks and stunts.

Most patients spend 3 to 4 months in formal physical therapy sessions with a progression to independent fitness program participation after that time period. Completing the skill phase many times takes place after physical therapy intervention. Full return to sport most times takes 6 to 8 months.

The following traces Marty's post-operative rehabilitation process as he progresses through the four phases.

Mobility
Post-operatively, Marty presented with a moderate amount of swelling in his knee. In order to obtain full range of motion, the swelling must be addressed with rest, ice, compression and elevation (R.I.C.E.). If swelling is not reduced, there is not room for the joint surfaces to move on each other. Early range-of-motion exercises were introduced to assist achieving mobility. These exercises focused not only on bending and straightening the knee, but on achieving a normal walking pattern. The focus initially was on obtaining full knee extension to facilitate a normal walking pattern with gradual work on flexing the knee.

Post-operatively, Marty presented with a hinged knee brace and two crutches. Both of these devices provide stability and protection to the knee joint in the early healing phase. Marty was weaned off of the crutches in 1 to 2 weeks. Initially, he walked with a stiff-legged movement pattern instead of bending his knee. This pattern was due to the swelling, stiffness, weakness and loss of neuromuscular control. This habit was broken through over-exaggerating his normal walking movements and toning those movements down as he improved over time.

General time frame goals for achieving full range of motion (approximately 135 to 140 degrees) were as follows: (1) 90 degrees in two weeks, (2) 120 degrees in four weeks, and (3) 135 degrees by six weeks. Most patients achieve these goals with early intervention. Through controlling swelling, initiating early motion exercises and re-establishing a normal walking pattern, Marty was on his way through the mobility phase of rehabilitation.

Stability
The stability phase involved developing strength to support Marty's knee joint. This phase was initiated early on with the mobility phase to help facilitate the normal walking pattern. The quadriceps muscles on the front of the thigh are vital for supporting body weight with standing and walking. Early isometric and isotonic exercises assist in re-educating these muscles to help with weight bearing activities (standing, walking). Examples of these exercises include quadriceps/hamstring isometrics and leg-raises.

Marty had a difficult time in getting his quadriceps muscle to fire initially. All techniques were implemented to re-educate these muscles to assist Marty with walking without crutches. Stability exercises involve not only addressing the knee joint musculature, but also strengthening the ankles, hips, back and abdominal muscles. These muscles also assist in supporting the knee joint.

Additionally, the hamstring muscles on the back of the thighs must be addressed. With regular daily activities such as walking, the hamstring muscles prevent excessive forward movement of the tibia (the lower leg bone). The ACL also prevents this excessive movement. To protect the newly reconstructed ligament, the hamstrings must be strengthened.

One point to keep in mind at this junction in time is what type of graft was used for the reconstruction. Depending on the type of graft, certain precautions should be taken. If the patient's own hamstring muscle was used for the graft, then proceeding with exercises directed at the hamstring muscles should be taken slowly (i.e. hamstring curls) until the 5 to 6 week time period. This time period will allow for adequate healing in the hamstring region. Proceeding too aggressively with hamstring strengthening in this case may result in a hamstring strain setting the patient back even further.

If the patellar tendon graft was used, as in Marty's case, then less attention needs to be paid concerning proceeding too aggressively with hamstring strengthening.

During the stability phase, Marty was challenged to address balance and proprioceptive issues in his knee. This process involves retraining the nerves and pathways to the brain on how Marty's knee adapts to changes in position and movements. The full return of these pathways is a slow, ongoing process that takes time. This retraining was integrated into the third phase, Controlled Mobility.

Controlled Mobility
Marty is currently in the controlled mobility phase. The controlled mobility phase of rehabilitation involves developing the strength to move the knee joint in a controlled manner as required to complete an activity successfully. This phase focuses on functional activities that integrate multiple planes of movement versus straight plane movements. Activities during this phase are a precursor to performing skilled movements.

Movements during this phase are performed more slowly and with less intensity. As these movements are perfected, they are sped up and may be transferred to the skill phase. In the case of wakeboarding, the squat position or squat jump movement are frequently performed when preparing to jump or after performing a jump. Performing a squat or squat jump correctly on a stable surface such as the ground must be performed safely and in a controlled manner before progressing to an unstable surface such as a wakeboard in water.

The controlled mobility phase involves the specific retraining of the neuromuscular system. This system involves the constant communication of the nerves and muscles to coordinate smooth, controlled actions and movements. With repetition, the coordination between the nervous system and musculoskeletal system improves. Improved coordination leads to eventual successful completion of a skill.

Skill
The last and most exciting phase of rehabilitation for Marty will be the skill phase. The focus during this phase will involve sports specific activities. There will be a wide range of activities during this phase from the basic principles of riding the wakeboard to the advanced techniques of tricks and stunts.

Marty will be seen during the early part of this phase and progressed to an independent maintenance program. He will be educated on timelines and progressions to promote a gradual return to sports activity. Marty's full return to sports activity will take 6 to 8 months. He will complete formal physical therapy intervention at the 3 to 4 month time period. During this 2 to 3 month lapse of time before full return to sport, it will be of vital importance for him to maintain and continually progress his strength and exercise tolerance independently. To prevent future injury, a regular maintenance, strengthening, and conditioning program must be maintained.

An additional measure for injury prevention includes custom bracing. Bracing, many times, is physician dependent. Custom bracing will be performed later in the rehabilitation process when Marty's muscle girth has improved. If performed too soon, his muscle girth will grow out of the brace.

As he develops more confidence in his skill performance, he will be able to progressively return to full sports participation.

The preceding four phases provide a general, informative guideline on Marty's rehabilitation process after ACL reconstruction. Many patients differ in their presentation and time frame for achieving goals throughout these phases, depending on whether or not additional pathologies were present. The list below provides a summary of general guidelines, post-operatively during the rehabilitation process, that most patients have questions about.