Re: Best ACL rehab protocol

[Guest guest]

We started supplementing typical 3x per week therapy (physician¹s protocol)

with the Cybex Arc Trainer workouts with great results. We used a standard

progression to build work capacity and familiarity with the machine as early

as 4 weeks post op in 8 female soccer players. 1 min on 1 min off to 4 min

on 1 min off and then back down over the course of 4-6 weeks. Each week we

slowly increased the resistance and/or speed requirements as they began to

gain strength and fitness.

The gains in cardiovascular response and strength endurance were way above

average, and the psychological benefit of being able to sweat and work at a

higher intensity with no pain in the knee during an exercises that (to the

subject) felt like a running motion, seemed to be exactly what we were

looking for. We have 3 studies up on the Cybex Institute website at

http://www.cybexinstitute.com/research.aspx that were duplicated on this

population at 12 weeks post op. And while we have not completed our studies

on exact protocols for the ACL return to sport population, we did notice 4

of 8 female soccer players running faster 20 times in their return to sport

test than they ran pre-injury. 6 of 8 players performed better in their

conditioning soccer conditioning test than the scores they recorded

pre-injury, and all 8 performed better in a single leg hop for distance test

than they had done pre-injury. More research needs to be done on this device

and it¹s effect on strength, strength endurance and functional capacity, but

the initial work seemed to give us the supplemental benefit we were looking

for in speed and cardiovascular endurance as well as strength and functional

hopping gains.

Moody

Soccer FIT Academy / CAP

Overland Park, KS USA

[Guest guest]

The below presentations may help you devise an appropriate programme:

http://video.nih.no/Congress2005/24.06%20Friday/saga-a/24/Symposium%20-%20Preven\

ting%20knee%20ligament%20injuries/Tron%20Krosshaug/Krosshaug%20-%20Non-Contact%2\

0ACL%20injury%20mechanisms/Non-Contact%20ACL%20injury%20mechanisms.swf

http://video.nih.no/Congress2005/23.06%20Thursday/SagaC/Symposium%20-%20Handball\

%20injury%20prevention/Grethe%20Myklebust/Myklebust%20-%20Prevention%20of%20ACL%\

20injuries%20in%20Norwegian%20team%20handball/Myklebust%20-%20Prevention%20of%20\

ACL%20injuries%20in%20Norwegian%20team%20handball.htm

http://video.nih.no/Congress2008/28B_14.10_Slauterbeck/28B_14.10_Slauterbeck.htm

http://video.nih.no/Congress2008/27C_09.10_Ekegren/27C_09.10_Ekegren.htm

http://video.nih.no/Congress2008/26A_16.15_Beynnon/26A_16.15_Beynnon.htm

From the archives:

The following article and a few others stresses the importance of not

relying on passive evaluation of ACL integrity, especially for evaluating

proprioceptive loss in ACL deficiency. It concludes that assessment of

failure of the injured individual to appreciate lower extremity movement is

essential. Other articles address different aspects of this very common

sporting injury, such as the prolonged time taken for proprioception to

return to the surgically treated knee.

--------------------------

Detailed analysis of proprioception in normal and ACL-deficient knees

Pap G, Machner A, Nebelung W, Awiszus F

J Bone Joint Surg Br 1999 Sep;81(5):764-8

We assessed proprioception using threshold levels for the perception of knee

movement at slow angular velocities (0.1 degrees/s to 0.85 degrees/s) in 20

patients with unilateral tears of the anterior cruciate ligament (ACL) and 15

age-related control subjects. Failure to detect movement was also analysed.

The threshold levels of detection did not differ between the damaged and

undamaged knees in the patients or between the patients and the control

group. Failure to appreciate movement, however, was significantly greater in

knees with ACL loss compared with the undamaged knees of patients and the

control group. Our findings show a proprioceptive deficit in the absence of

the ACL. Measurements of threshold levels of detection of passive movement

alone are not suitable for the evaluation of proprioceptive loss in ACL

deficiency; assessment of failure to appreciate movement is essential.

---------------------

Proprioception in the nearly extended knee. Measurements of position and

movement in healthy individuals and in symptomatic anterior cruciate ligament

injured patients

Friden T, D, Zatterstrom R, Lindstrand A, Moritz U

Knee Surg Sports Traumatol Arthrosc 1996;4(4):217-24

Proprioception of the knee was measured in 19 healthy individuals to evaluate

whether there were any differences between extension and flexion movements

from two different starting positions. The threshold before detecting a

passive movement, visual estimation on a protractor of a passive change in

position (30 degrees angular change) and active reproduction of the same

angular change were registered. The reference population was tested twice to

study normal variation and reproducibility, followed by the evaluation of 20

patients with chronic, symptomatic and unilateral anterior cruciate ligament

(ACL)-deficient knees.

In the normal population no differences were found between the right and the

left leg, men and women, or measurements made at the first and at the second

test occasion. The thresholds from a starting position of 20 degs were lower

for extension than for flexion. When comparing the thresholds for extension

between the 20 degs and the 40 degs starting position, lower values were

found in the more extended position. The thresholds for flexion were lower

from the 40 degs starting position than from the 20 degs starting position.

The active reproduction of an angular change of 30 degs was more accurate

during flexion (30 degs-60 degrees) than during extension (60 degs-30

degrees). There were no differences in the reproduction tests or in

thresholds from the 40 degs starting position between the patients and the

normal group, but the patients had higher thresholds from the 20 degs

starting position, in movements towards both extension 1.0 deg (range 0.5

deg-12.0 degs) and flexion 1.5 degs (range 0.5 deg-10.0 degs) than the normal

group 0.75 deg (range 0.5 deg-2.25 degs) and 1.0 degree (range 0.5 deg-3.0

degs), respectively.

Thus, information of passive movements in the nearly extended knee position

was more sensitive towards extension than towards flexion in threshold tests

and the sensitivity improved closer to full extension, which implies a

logical joint protective purpose.

In this nearly extended knee position, which is the basis for most

weight-bearing activities, patients with symptomatic ACL-deficient knees had

an impaired awareness in detecting a passive movement. There were no

differences in the more flexed position or in the reproduction tests between

the patients and the normal group, and reproduction tests in the present form

seem less appropriate to use in the evaluation of ACL injuries.

---------------------

Proprioception in people with anterior cruciate ligament-deficient knees:

comparison of symptomatic and asymptomatic patients

D, Friden T, Zatterstrom R, Lindstrand A, Moritz U

J Orthop Sports Phys Ther 1999 Oct;29(10):587-94

STUDY DESIGN: Nonrandomized prospective study. OBJECTIVE: To evaluate

proprioception in 2 groups of patients with anterior cruciate ligament (ACL)

deficiency who had different severity of symptoms. BACKGROUND: Defective

proprioception has previously been found in patients with ACL-deficient

knees. It has been suggested that sensory receptors of the ACL and other knee

joint ligaments contribute to proprioception and knee joint function and

stability.

METHODS AND MEASURES: A total of 17 patients with ACL deficiency (mean [sD]

age, 28.8 ± 5.6 years; range, 22-39 years) with few, if any, symptoms were

compared with 20 patients with ACL deficiency (mean [sD] age, 26.6 ± 6.1

years; range, 18-39 years) having instability and episodes of giving way. The

groups were compared with each other and with an age-matched reference group

of 19 nonimpaired subjects. Their mean (SD) age was 25.6 ± 3.7 years (range,

20-37 years). Three tests of proprioception were used: threshold to detection

of passive motion from 2 starting positions (20 degs and 40 degs of knee

flexion) toward flexion and extension, active reproduction of a 30 degs

passive angle change, and visual reproduction of a 30 degs passive angle

change. The Wilcoxon rank sum test was used for between-group comparisons.

RESULTS: Symptomatic patients had higher threshold to detection of passive

motion in their injured side in the flexion trial from 20 degs (median of 1.5

deg vs median of 0.5 deg) and in the extension trial from 40 degs (median of

1.0 deg vs median of 0.5 deg) than the asymptomatic patients. No differences

were found in the other threshold tests, active or visual reproduction tests.

CONCLUSIONS: Patients with severe symptoms related to ACL deficiency were

found to have inferior proprioceptive ability in some measurements compared

with patients with a good knee function. The findings indicate that

proprioceptive deficits might influence the outcome of an ACL injury treated

nonoperatively.

----------------------

***This article drew the disturbing conclusion that anterior cruciate

ligament reconstruction does not improve proprioception for a considerable

period after surgery (at least in the patients examined in this study).

Proprioception in anterior cruciate ligament-deficient and reconstructed knees

Mac PB, Hedden D, Pacin O, Sutherland K

Am J Sports Med 1996 Nov-Dec; 24(6): 774-8

Section of Orthopaedics, University of Manitoba, St. Boniface General

Hospital, Winnipeg, Canada

Proprioceptive function of the knee was quantified and compared in three

groups of patients: those with anterior cruciate ligament deficiency, with

hamstring tendons-ligament augmentation device anterior cruciate ligament

reconstructions, and with bone-patellar tendon-bone anterior cruciate

ligament reconstructions. A total of 32 subjects, including 6 uninjured

control subjects, were tested for threshold to perception of passive motion

of the knee. All other sensory input was neutralized and testing occurred in

the 30 degrees to 40 degrees range of knee flexion. The noninvolved

contralateral knee served as a control for each subject. Each leg was moved

at 0.5 deg/sec into flexion or extension in a random sequence. The variables

of age, KT-1000 arthrometer scores, injury-to-surgery interval,

injury-to-followup interval, and patient satisfaction were statistically

analyzed for correlation with threshold to perception of passive motion of

the knee.

Control subjects showed no statistically significant differences in threshold

between their two knees. The three test groups all showed significantly

higher values in the involved knee compared with the noninvolved knee.

However, no statistically significant differences were found between the

groups, including controls, with respect to mean threshold to perception of

passive motion.

According to these results, anterior cruciate ligament reconstruction did not

improve proprioception in the patients in this study.

----------------------

*** The following study indicated that a minimum of 18 months after ACL

reconstruction may be needed for complete restoration of the proprioceptive

function in knees, although the mean position sense in all patients gradually

improved from 9 months.

Proprioceptive improvement in knees with anterior cruciate ligament

reconstruction

Iwasa J, Ochi M, Adachi N, Tobita M, Katsube K, Uchio Y

Clin Orthop 2000 Dec;(381):168-76

The correlation between the prospective course of proprioceptive improvement

and knee stability after anterior cruciate ligament reconstruction was

investigated in 38 patients. Proprioception, on the basis of the patient's

capacity to reposition the limb accurately, was evaluated at 3-month

intervals for 24 months after hamstring graft anterior cruciate ligament

surgery. Knee stability was evaluated concurrently with a KT-2000 knee

arthrometer. Thirty patients experienced improvement in postoperative

position sense in at least one of the examinations, although eight patients

had no improvement at any time. Of the 30 patients who had improvement, 28

maintained improved position sense from 18 months to the final followup.

Thirty patients maintained significantly better knee stability for a

postoperative period of at least 24 months.

These results indicated that a minimum of 18 months after anterior cruciate

ligament reconstruction may be needed for complete restoration of the

proprioceptive function in knees, although the mean position sense in all

patients gradually improved from 9 months. Improvement in postoperative knee

stability may have facilitated recovery of proprioception.

-------------------

*** The following study also showed that patients for a prolonged time after

ACL reconstruction showed no significantly better proprioception compared

with the preoperative group. In addition, this study showed a positive

influence of a knee bandage on the proprioception of the injured knee, a

finding that may support the frequent practice of competitive lifters wearing

of knee wraps, even if not tightly worn, to protect the knees and enhance

force production.

Knee joint proprioception in normal volunteers and patients with anterior

cruciate ligament tears, taking special account of the effect of a knee

bandage

Jerosch J, Prymka M

Arch Orthop Trauma Surg 1996;115(3-4):162-6

Proprioception of the knee joint was tested in 30 healthy volunteers with

clinically inconspicuous knee joints. To examine proprioception, an angle

reproduction test was performed. We could not document any differences

between the left and the right knee joint or between men and women. At the

mid-range, proprioception was worse compared with the end range of motion. In

addition, 25 patients with an isolated rupture of the anterior cruciate

ligament were evaluated, 14 before and 11 after operative anterior cruciate

ligament (ACL) reconstruction.

Preoperatively, there was a significant deterioration of proprioception

compared with the control group. We were able to show a positive influence of

a knee bandage on the proprioception of the injured knee. Patients after ACL

reconstruction showed no significantly better proprioception compared with

the preoperative group.

--------------------

Proprioception after rehabilitation and reconstruction in knees with

deficiency of the anterior cruciate ligament: a prospective, longitudinal

study

Fremerey RW, Lobenhoffer P, Zeichen J, Skutek M, Bosch U, Tscherne H

J Bone Joint Surg Br 2000 Aug; 82(6): 801-6

We assessed proprioception in the knee using the angle reproduction test in

20 healthy volunteers, ten patients with acute anterior instability and 20

patients with chronic anterior instability after reconstruction of the

anterior cruciate ligament (ACL). In addition, the Lysholm-knee score,

ligament laxity and patient satisfaction were determined.

Acute trauma causes extensive damage to proprioception which is not restored

by rehabilitation alone. Three months after operation, there remained a

slight decrease in proprioception compared with the preoperative recordings,

but six months after reconstruction, restoration of proprioception was seen

near full extension and full flexion. In the mid-range position,

proprioception was not restored. At follow-up, 3.7 ± 0.3 years after

reconstruction, there was further improvement of proprioception in the

mid-range position. There was no difference between open and arthroscopic

techniques. The highest correlation was found between proprioception and

patient satisfaction.

After reconstruction of the ACL reduced proprioception may explain the poor

functional outcome in some patients, despite restoration of mechanical

stability.

--------------------------

Proprioceptive sensitivity and performance in anterior cruciate

ligament-deficient knee joints

Fischer-Rasmussen T, Jensen PE

Scand J Med Sci Sports 2000 Apr; 10(2): 85-9

We studied the performance and proprioception of the knee joint in a group of

non-reconstructed anterior cruciate ligament (ACL)-deficient (n=20) patients

and compared them with a group of ACL-reconstructed patients (n=18) and a

group of healthy controls (n=20). Each patient was scored according to

Lysholm and Tegner and was then asked to subjectively evaluate the

performance of the injured knee and the degree of retropatellar discomfort.

The knee joint laxity was measured. The performance was assessed based on the

performance in a triple jump test and a one-leg one-step leap test. The

proprioception in the knee was measured as the threshold when passive

movement was detected and as the ability to reproduce a flexion angle from a

start position of 60 degrees of flexion or from full extension of the knee.

All tests were performed on both legs. The scoring systems and the subjective

evaluation showed significant differences between the reconstructed and the

non-reconstructed patients.

No significant difference in knee joint laxity was found between the two

groups. In the triple jump test and the one-step leap test, both groups

performed significantly worse on the leg with the injured knee joint than on

the non-injured leg. The proprioceptive tests showed decreased ability to

recognize and reproduce a prior angle from a start position of 60 degrees.

The threshold to detection of passive movement with the injured knee was

significantly increased in both groups of patients. No difference was found

between the dominant and non-dominant knee in the control group. When

reproduction of the same angles started from full extension, the groups did

not differ.

These data show that decreased performance and changes in the proprioception

of the knee joint accompany ACL rupture.

--------------------------

*** The following article addresses the important issue of the effects of

lateral stability in the ACL deficient knee.

Analysis of the significance of the measurement of acceleration with respect

to lateral laxity of the anterior cruciate ligament insufficient knee

Yoshimura I, Naito M, Hara M, Zhang J Int Orthop 2000;24(5):276-8

The purpose of this study was to assess dynamically the lateral thrust of

anterior cruciate ligament (ACL) insufficient knees, and from the findings

determine any relationship between ACL insufficiency and the later

development of osteoarthritis (OA).

We investigated 80 knees in 40 patients awaiting ACL reconstruction and 25

knees of 25 patients, which had undergone ACL reconstruction. An acceleration

sensor was fixed to the anterior tibial tubercle and this 'acted' in two

directions--medial lateral and perpendicular. The peak value of the lateral

acceleration immediately after heel strike was significantly greater in the

ACL insufficient knees when compared to their opposite normal knees. When the

periods from injury were compared, the lateral thrust of the injured side

after 3 years or more was significantly greater than in the first 3 years.

There was no significant difference between the normal knees and the ACL

reconstructed knees.

The results indicated that the lateral acceleration peak value was

significantly greater in the ACL insufficient knees than in their opposite

normal knees.

-----------------------

Different patterns of meniscal tears in acute anterior cruciate ligament

(ACL) ruptures and in chronic ACL-deficient knees. Classification, staging

and timing of treatment.

Cipolla M, Scala A, Gianni E, Puddu G

Knee Surg Sports Traumatol Arthrosc 1995;3(3):130-4

Through the retrospective study of 1103 reconstructions of the anterior

cruciate ligament (ACL) performed between 1984 and 1993, we try to outline

the natural history of meniscal tears in acute lesions and in chronic

insufficiency of the ACL. According to a more accurate evaluation of the

clinical evolution, ACL-deficient knees can be classified into four different

stages: acute, subacute, subchronic and properly chronic laxities. While

acute injuries show a higher rate of lateral meniscus tears, chronic laxities

are very frequently associated with severe medial meniscus lesions. Subacute

and subchronic stages seem therefore to be the most favourable phases for ACL

reconstruction, because of the lower percentage of severe associated meniscus

tears and the minor risk of arthrofibrosis.

===============

FEMALE SUSCEPTIBILITY TO ANTERIOR CRUCIATE LIGAMENT TEARS

Ogden

Writer's comment: When my English 104F class was assigned to write a literature

review, I was quick to decide that my topic would be the occurrence of ACL tears

in women. After playing soccer for years, I finally experienced a ruptured ACL

in high school and have been interested in the subject ever since. Recently, I

have become increasingly aware that the incidence of females who tear their ACL

is much higher than that of men. By sifting through many medical journals, I

found that female susceptibility to ACL tears was currently being investigated.

Statistical information based on experiments was useful in deciding a trend, but

more importantly, I learned that recent experiments help to plan future

preventative programs for women. Writing this review has given me the

opportunity to research a topic that genuinely interests me, but perhaps more

importantly, provided me with the skills to condense large amounts of

information into a readable composition that can inform a diverse audience.

— Ogden

Instructor's comment: In this literature review assignment, students must

survey, organize and summarize the current scientific or medical studies on a

particular topic. Ideally, the writer will sum up the state of scientific

knowledge on her chosen subject, indicating which research questions have been

answered and which ones remain unsolved. The substantial challenges of the

literature review primarily involve topic selection and information

organization. made a wise move in selecting a topic close to her

heart. Her exhaustive literature searches yielded just the right amount of

information, which organized into logical subcategories that explain

why women are more susceptible than men to ACL tears and what a coach or athlete

might do to prevent such injuries. 's efforts have resulted in a piece

that coaches of female sports teams can actually use to educate themselves on

strategies for preventing these debilitating injuries.

—Anne Fleischmann, English Department, Sierra College

Introduction

Women involved in physical activity are eight times more likely to

rupture their anterior cruciate ligament (ACL) than men who are involved in the

same physical activity (Lephart 2002). With this number on the rise, researchers

are currently investigating some contributing factors to ACL injury in females.

Targeted factors in females include anatomical positioning of hips and lower

extremities, neurologic recruitment of muscle groups, reflex speed, and hormone

influence on laxity within the knee joint. Although anatomical features and

neurological responses are difficult to alter, recent exploration has

demonstrated that prevention programs focused on muscle development and

proprioception skills might decrease the risk of an ACL tear in some women

(Huston 2000). This review will expand on differences in anatomical structure,

neurological processes, physiological mechanisms and hormonal fluctuation in

females, and will further detail prevention methods currently being tested to

decrease the occurrence of ACL ruptures in women.

Anatomical Differences

While men and women exhibit the same physical features in their lower

extremities, the size and positioning of these features differ. One difference

between males and females is the width of the femoral notch. On average, men

have an intercondylar notch slightly larger than that of females (Shelbourne

1998). The larger notch has been speculated to facilitate movement and prevent

impingement on the ACL (Huston 2000). Lund-Hanssen et al. concluded from a study

performed on female handball players that women having a femoral notch width

less than 17mm were six times more likely to tear their ACL than men (1994). A

narrow femoral notch can inhibit range of motion and pinch the ACL during

flexion (Huston 2000). Another anatomical feature that contributes to the

likelihood of ACL ruptures in women is the way the knee is aligned with the hip

(Huston 2000). When compared to women's, the narrow hips of males allow the knee

joints to align at a fairly minimal quadriceps femoris angle, or Q angle, with

their hips. In contrast, the Q angle in women is much larger due to increased

hip width. While increased hip width in females allows for ease in pregnancy and

childbirth, a large Q angle causes a tremendous amount of force to be exerted on

the medial aspect of the knee joint. When a large load is forced upon the knee

during jumps or pivots, the ACL is strained and may not be able to prevent

tibial slipping (McAlindon 2002). Unregulated tibial shiftage can lead to

rupture of the ACL.

Neuromuscular and Physiological Factors

Both reflex control and proprioception play a large role in

coordination of muscle firing and balance. Without quick response to force, the

knee joint can often experience ligament ruptures. When men and women were both

tested to judge the ability of their knees to handle a landing following a jump,

reports concluded that women exhibited more force and greater extension during

landing (Chappell 2002). These findings led to the idea that women might have

slower motor reflexes than their male counterparts (Kaplan 2002). On a similar

note, men and women reportedly recruit muscles differently (Huston 2000). While

most men successfully used their hamstrings to land a jump, those women who used

more of their quadriceps to land a jump experienced injury to the knee (Huston

2000 and Lephart 2002). Such studies support the hypothesis that men and women

differ in both neurological and physiological reactions to physical

disturbances.

Because studies show that there may be a difference in the reaction

times and motor unit recruitment, researchers began to run tests to see if

individuals who have trained to increase reaction time would tear their ACL as

often as an untrained individuals. T.E. Hewett (1999) conducted a test that

divided individuals into three groups: " male athletes, " " female athletes, " and

" untrained females. " These three groups were then monitored over the course of

their athletic seasons. Only 2 out of 434 males exhibited serious knee injuries

with only one injury from a noncontact situation, while 2 of 366 trained female

athletes exhibited serious knee injuries, neither of which resulted from

noncontact situations. In the final group of untrained female participants 10 of

463 subjects exhibited serious knee injuries, eight of which were noncontact

injuries, supporting the idea that neuromuscular reactions of untrained female

athletes are slower than those of trained female and male athletes (Hewett

1999).

Researchers are investigating a related aspect of neurology with

regards to muscle firing pattern. Lephart et al. (2002) have been

observing motor reflex arcs in women and have speculated that women may have a

longer electromechanical delay than men. When a person senses a disruption, she

immediately communicates to the brain via alpha motor neurons to produce both

spinal reflexes and muscle spindle triggering. Such messages usually take a

short amount of time to reach the target tissue, but recent evaluations suggest

that males and females exhibit slight differences in reaction times (Lephart

2002). The electromechanical delay can reduce muscle reaction and therefore

allow ligaments such as the ACL to be stretched for a longer period of time than

they normally would. Shorter electromechanical delay can actually bring the

surrounding muscles to flexion, in turn reducing the load forced on the ACL

(Lephart 2002). Slow motor reflex and quadriceps overuse leaves untrained

females participating in physical activity at an extremely high risk for ACL

injury.

Hormone Fluctuation

Females experience large fluxes of hormone levels including estrogen,

progesterone, and sometimes relaxin. Because of such great fluctuations in the

hormones of females, researchers have linked rate of ACL injury with levels of

estrogen (Huston 2002). Unfortunately, administering high doses of hormones to

human patients poses great health risks, so most studies are conducted on

animals. In a study performed by Slauterbeck (1999) female rabbits were

subjected to different levels of estrogen to test for laxity in the knee joint.

The ACL load failure rate was measured to be higher in those rabbits that

received the estrogen supplements. This supported the hypothesis that females

have increased laxity in their knee joints due to increased estrogen levels. The

study further concluded that estrogen might play a factor in weakening the

strength of the ACL in women (Slauterbeck 1999). In addition to estrogen,

relaxin, though present in minute amounts, may also be a contributing factor to

ACL tears in females (Liu 1996). This hormone, usually present in high amounts

during pregnancy, has been detected in trace amounts in ovulating females (Lui

1996). Relaxin serves to create laxity in the hip joints during childbirth, but

even small amounts found in knee joints might validate the theory that ACL

ruptures in females are linked to joint laxity (Lui 1996). Further studies must

be conducted to confirm such hypotheses.

Additional research by H. Lui et al., revealed that there were

hormone receptors for estrogen and progesterone on the ACL, suggesting that both

hormones might influence the function of the ACL (1996). When researchers tested

the precursor to estrogen, estradiol, they found that the rate of collagenous

material decreased when excess estradiol was introduced into the system. Many

hormone studies relate female menstrual cycles to occurrence of ACL injury

(Huston 2000). While not completely supported, the hypothesis stems from the

idea that estrogen and progesterone levels are high during ovulation, therefore

creating a greater risk of ACL injury (Huston 2000). T.E. Hewett suggests oral

contraceptives as a way to regulate hormone levels in females and further

suggests that the regulation of the hormones can serve to decrease the

occurrence of ACL tear (2000). Researchers suspect that if ACL injury is related

to hormone flux, the occurrence of injury in females will decrease through the

introduction of a consistent level of estrogen and progesterone.

Prevention

Females do have options to decrease their chance of severe knee injury.

Because altering physical structure is impossible, Huston et al. suggests

internal rotation exercises, which include medial hamstring exercises (2000).

Such exercises allow the muscles surrounding the knee to support the medial load

exerted from a wide Q angle (2000). While anatomical structure cannot be

drastically changed, neurological and physiological responses most definitely

can be (2000). Huston et al. (2000) along with Hewitt et al. (2000) suggest that

neuromuscular strength and proprioception drills, such as balance board

exercises, might stabilize the knee in strenuous situations. In the study

performed by Hewett et al., where trained and untrained female athletes were

observed during their athletic seasons, the researchers concluded that the women

who had some sort of previous muscle training exhibited a much smaller number of

ACL tears than those who were completely untrained (1999). Other suggestions

from Hewett et al. explain that plyometric training and safer landing techniques

can significantly reduce injury or prepare the surrounding muscles of the knee

for tibial shiftage (1999). Preparation exercises allow the brain to adjust to

distinct movements such as cutting, pivoting, or jumping, hence creating quicker

physiological responses.

Conclusion

The high rate of ACL tears in females has spurred a large number of

researchers and physicians to look into the mechanism of injury in great detail.

Until recently, the ACL injury to women was treated in the same manner as male

patients. However, details about female joint position, condyle widths,

neurological patterns, and pelvic and/or knee laxity have given researchers the

chance to formulate methods of possible prevention specific to females. With an

increasing number of women participating in physical activity, especially in

sports, prevention programs are beginning to flourish. Most programs focus on

increasing proprioceptive skills and reaction time. Programs can be selected

based on level of athleticism. Those involved in competitive sports should have

a more rigorous workout to prepare for greater load weight. Cone and agility

drills combined with jump-landing techniques are exercises that have the

greatest effect of reducing injury (Hewett 1999). Since females are at such high

risk for ACL rupture, athletic trainers, physical therapists and physicians

should encourage their female patients to embrace a strengthening and timing

program that will decrease the effects of factors contributing to ligamentous

injury to the knee.

References

1. Chappell, J.D., Yu, B., Kirkendall, D.T., and Garrett, W.E. 2002. A

Comparison of Knee Kinetics between Male and Female Recreational Athletes in

Stop-Jump Tasks. The American Journal of Sports Medicine, 30 (2): 261-268.

2. Hewett, T.E. 2000. Neuromuscular and Hormonal Factors Associated with Knee

Injuries in Female Athletes: Strategy for Intervention. Sports Medicine, 29:

313-327.

3. Hewett, T.E., Lindenfield, T.N., Riccobene, J.V., and Noyes, F.R. 1999. The

Effect of Neuromuscular Training on the Incidence of Knee Injury in Female

Athletes: A Prospective Study. The American Journal of Sports Medicine, 27 (6):

699-705.

4. Huston, L.J., Greenfield, M.L., and Wojtys, E.M. 2000. Anterior Cruciate

Ligament Injuries in the Female Athlete: Potential Risk Factors. Clinical

Orthopaedics and Related Research, 372: 50-63.

5. Lephart, S.M., Abt, J.P, and Ferris, C.M. 2002. Neuromuscular Contributions

to Anterior Cruciate Ligament Injuries in Females. Current Opinion in

Rheumatology, 14: 168-173.

6. Lui, S.H., Al-Shaikh, R., Panossian, V., Sen-Yang, R., , S.D.,

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==================

Carruthers

Wakefield, UK

>

> I was wondering what is the best or at least the best that you know of ACL

rehab protocol ? I suppose one aspect of my " best " criteria is a speedy

recovery but I'm not going to push it so as to injure myself again.

>

> thank you,

> Teri Pokere

> Brisbane,Australia

>