Keywords anterior cruciate ligament - knee/surgery - soccer - rehabilitation
Introduction
Soccer (also known as football in the United Kingdom), is the most popular sport in
the world, with over 265 million active players worldwide.[1 ] It is the main cause of sports injuries.[2 ] One of the most common knee injuries is the rupture of the anterior cruciate ligament
(ACL),[3 ]
[4 ]
[5 ]
[6 ] a serious injury that predominantly requires surgical treatment.[7 ]
[8 ] Although the risk of this injury is low in the general population, it is considerably
higher among team sports athletes.[9 ]
In professional football, this injury has important economic consequences: the absence
from training and competitions for months, associated with issues such as compliance
with contracts, schedules, advertising engagements and other engagements often entails
enormous pressure for a quick return to sport.
The primary goal of ligament reconstruction in these patients is to restore the physiological
function of the injured knee, to enable the athlete to return to play soccer as soon
as possible, with the same proficiency level as before the injury, and to help prevent
the degenerative processes that could take place.[10 ]
[11 ] There is no consensus regarding the best treatment, nor regarding the time required
for rehabilitation and safe return to competitive activities.[9 ]
[10 ]
[12 ] Given the lack of solid evidence, the experience of experts is an important factor
in the management of these cases. Our goal is to describe the treatment of ACL injuries
in professional soccer athletes performed by orthopedists affiliated to soccer teams
competing in the Brazilian Soccer Championship.
Materials and Methods
This cross-sectional study was approved by the Ethics in Research Committee of Universidade
Federal de São Paulo, under opinion number 2.221.990. It was developed based on interviews
with 61 orthopedists affiliated to Brazilian professional soccer teams, mainly those
that compete in the Brazilian Soccer Championship. The experts were approached individually
by the research team members by telephone or via email. After signing the informed
consent form, a multiple choice questionnaire containing 17 questions was applied
to every orthopedist. The questionnaire was based on models used in international
research, and it was adapted by the authors and approved by a committee of medical
specialists in the field.
The questions were developed in order to obtain data about the interviewees' profile
and their experience, treatment methods, surgical techniques and postoperative practices.
In the research, the following software were used: the Statistical Package for the
Social Sciences (SPSS, IBM Corp., Armonk, NY, US), version 20.0, Minitab (Minitab,
LLC, State College, PA, US), version 16, and Excel Office 2010 (Microsoft Corp., Redmond,
WA, US). For the quantitative variables, a complete descriptive analysis was performed.
We obtained low variability in the responses (coefficient of variance [CV] < 50%),
which demonstrates the homogeneity of the data. The qualitative variables were analyzed
through the calculation of absolute and relative frequencies, tests of equality of
proportions, analysis of the statistical 95% confidence intervals (95%CIs) and p -values (statistical error allowed) ≤ 0.05. The data obtained were compared to those
found in the literature. The results that differed from the established parameters
were detailed.
Results
From a total of 61 participating specialists, 31 (50.8%) were affiliated to teams
that form what is called in Portuguese “Série A” (the major league, or first division),
which compete in the Brazilian Soccer Championship; 21 (34.4%) respondents were affiliated
to teams from “Série B” (the second division); and 9 (14.8%) were affiliated to teams
from “Série C” or “D” (the third and fourth divisions), which compete in regional
soccer championships. [Table 1 ] describes the information obtained from the first three questions.
Table 1
Descriptor
Mean
Median
Standard deviation
CV
Q1
Q3
Min.
Max.
N
CI
Age (years)
47.43
46
8.63
18%
42
53
30
65
61
2.17
Time after graduation (years)
23.64
24
8.56
36%
18
30
6
41
61
2.15
Career in orthopedics (years)
20.33
19
8.89
44%
15
27
1
36
61
2.23
Regarding the definitive surgery after ACL injury, 45.9% of the respondents wait between
1 and 2 weeks to perform it after an acute and isolated ACL injury; 34.4% wait 2 to
3 weeks; 16.4% perform immediate surgery; and only 3.3% wait 4 to 6 weeks for the
definitive approach. Statistically, there was no difference between the waiting periods
of 1 to 2 weeks and 2 to 3 weeks (p = 0.196).
The preferred surgical technique was single incision and arthroscopically-assisted
single-bundle for 78.7% of the respondents, followed by double incision and arthroscopically-assisted
single-bundle for 16.4%; and by single incision and arthroscopically-assisted double-bundle
for 4.9%. No respondents opted for other alternatives.
Perforation of the femoral tunnel via the medial accessory portal (transportal) was
the choice for 50.8% of the respondents; 24.6% opted for the outside-in technique;
23%, for the transtibial technique; and only 1.6%, for the double incision.
The most commonly used autograft were quadruple flexor tendons for 49.2% of the respondents,
followed by patellar tendon autograft for 34.4%. In third place, the fivefold or sixfold
flexor tendon autograft for 13.1%, followed by the quadriceps tendon autograft for
3.3%. It cannot be said that there is a difference between the two most widely adopted
options (p = 0.099). [Figures 1 ] and [2 ] describe the main concerns mentioned by the respondents according to the chosen
autograft.
Fig. 1 Distribution of the answers obtained from question 6. Statistically, there was no
difference between the most recurrent response (“postoperative flexor muscle weakness”)
and the responses “graft loss or rupture” (p = 0.661) and “graft resistance and strength” (p = 0.105).
Fig. 2 Distribution of the answers obtained from question 5. The major concern was anterior
knee pain. Other conditions mentioned by 5.8% of the respondents included knee extension
block and absence of concern.
Continuous passive motion (CPM) is used in rehabilitation after ACL reconstruction
by 67.2% of orthopedists. Running in a straight line was allowed after 3 to 4 months
by 68.9% of the respondents, after 4 to 6 months by 21.3%, and after less than 2 months
by 9.8%. Exercises with a ball but with no contact with other athletes were allowed
after 4 to 6 months by 72.1% of physicians; 16.4% opted for allowing it after 6 to
8 months; 9.8%, after 2 to 4 months; and only 1.6%, after 8 to 10 months. No one has
opted for more than ten months of restriction.
Unrestricted return to sport was allowed by 65.6% of the respondents after 6 to 8
months postoperatively; 24.6% allowed the return after 8 to 10 months; 8.2%, after
4 to 6 months; and only 1.6 %, after more than 10 months. No respondents opted for
the release in less than 4 months. The main parameter used was the isokinetic strength
test (49.2%). The second most used criterion was rehabilitation and postoperative
time longer than 6 months (23%), followed by normal and painless physical examination
(13.1%), the hop test (9.8%), physiotherapy assessment (8.2%), and other parameters
(8.2%), among them the combination of the previously mentioned parameters with kinematics
and force platform, comparative contralateral functional tests, and the application
of the “Functional Movement Screen”.
The use of functional orthoses was only recommended by 9.8% of the specialists. Among
those who recommended it, 83.3% maintain orthoses for 2 weeks after surgery, while
16.7% maintain them for 3 weeks.
Regarding the percentage of professional soccer athletes who return to play professionally
after ACL reconstruction, 73.8% of physicians believe that over 90% return to the
previous professional level, 18% believe that about 80-90% return to the professional
level, and 8.2% believe that 60-80% return to professional soccer. [Figure 3 ] describes the responses obtained regarding the return to the previous (or higher)
level of performance when compared to the pre-injury level.
Fig. 3 Distribution of answers obtained from question 15. There was no statistical difference
between the “80-90%” (more frequent) and “60-80%” (p = 0.848) options.
[Figure 4 ] describes the distribution of the responses regarding the average number of ACL
reconstructions performed per year by the experts, while [Figure 5 ] describes the results related to the average ACL reconstructions performed per year
specifically on soccer players of all levels.
Fig. 4 Average number of reconstructions. The responses involving the values “25-50”, “50-100”
and “100-200” were statistically equal (p = 0.846 and p = 0.154).
Fig. 5 Average number of ACL reconstructions performed per year specifically among soccer
players. Statistically, the responses “25-50”, “10-25” and “< 10” did not show differences
(p = 0.696 e p = 0.154).
Discussion
The divisions system of the Brazilian Soccer Championship is based on the technical
quality of the teams and their performance in the previous year. The first division
is comprised of the teams with the best performances; then come the other divisions.
Regarding the present study, most respondents are affiliated to first-division teams,
and even though there were professionals affiliated to clubs from every division in
the study, it predominantly involved orthopedists who perform surgeries in athletes
of the highest national technical level. To the best of our knowledge, there are no
other similar studies in the Brazilian literature involving this many orthopedists
and traumatologists specializing in the field, and when reviewing the literature,
we found only three similar studies.[4 ]
[13 ]
[14 ]
The respondents were predominantly middle-aged doctors, long-time graduates with extensive
orthopedic and football experience. Most choose to wait one to four weeks for the
definitive surgical treatment after an ACL injury. Late ACL reconstruction was believed
to lead to lower risk of knee stiffness and arthrofibrosis.[15 ]
[16 ] However, more recent studies report that the acute reconstruction of these injuries
is safe, and does not increase the risk of knee stiffness.[15 ] According to Marcacci et al,[17 ] patients with acute ACL reconstruction returned to sports faster and with better
clinical results.
The respondents showed preference for the arthroscopic single-bundle ACL reconstruction
technique. This is a controversial topic, even though in the literature there are
no significant differences in multiple systematic reviews and meta-analysis in the
postoperative evaluation of patients who underwent both techniques.[18 ]
[19 ]
[20 ]
No respondents opted for the use of allografts for ACL reconstruction. The lack of
availability and the small number of biobanks in Brazil make this finding predictable,
and it is in agreement with foreign studies. Farber et al[4 ] reported that allografts were not the first choice of any of the surgeons, and most
orthopedists believe that allografts have a higher chance of failure. In fact, the
rate of new ACL injuries after allograft reconstruction is four to eight times higher
than that of autograft reconstruction in athletes and those who serve in the military.[3 ]
[4 ] There are no differences between allografts or autografts regarding the quality
of ACL injury repair.[21 ]
The preferred method for perforation of the femoral tunnel was the medial accessory
portal, followed by the outside-in technique and the transtibial technique. It is
known that this is another controversial topic in the literature, as illustrated by
Luzo et al[22 ] and Farber et al.[4 ] It has been shown in multiple biomechanical studies[ 23 ]
[24 ] that the femoral tunnel performed via the medial accessory portal covers more of
the ACL footprint in the femur than the transtibial tunnel. However, there is a lack
of significant and clinically relevant outcomes.[7 ]
[25 ]
The patellar tendon is considered an ideal graft choice, although problems such as
loss of sensation, patellar fracture, inferior patellar contracture, and loss of extension
torque have been reported after graft removal. The main concern associated with patellar
tendon autograft was anterior knee pain, a common and limiting complaint associated
with this surgical technique.[26 ] The use of flexor tendon autografts has been growing in popularity because many
reports suggest that their use leads to fewer local complications. Postoperative flexor
muscle weakness, graft strength and resistance, and graft loss or rupture were the
most mentioned concerns, also according to the findings in the literature.[15 ]
[26 ]
The rates of return to sport and recovery of knee function are not significantly different
between the two most commonly used graft groups,[27 ] although there are few well-designed and randomized studies comparing the methods.[26 ] Return to competition was allowed after six to eight months, predominantly without
the use of orthoses, as reported in other studies.[4 ]
[7 ]
[15 ] Although the isokinetic strength test was the main parameter used to allow the return
to sports, it is noteworthy that the questionnaire did not detail which device was
used or which protocol was applied, and we believe that this is an important topic
for future studies.
Most orthopedists believe that soccer players successfully return to sport and pre-injury
performance levels. A systematic review by Mohtadi et al[28 ] demonstrated a rate of return to sport from 63 to 97% for highly-competitive athletes,
a value consistent with the findings of Zaffagnini et al[12 ] (62% to 95%). The return to sport in European professional football (soccer) is
quite high, with 97% of the Union of European Football Associations (UEFA) Champions
League athletes returning to the same levels prior to injury after ACL reconstruction.
However, only 65% of these athletes continue to play at the same level after three
years.[29 ]
Although this is a study with level V of evidence, the opinion of multiple experts
with varying surgical volume and more than 200 ACL reconstructions per year revealed
important information. We must, however, remember the biases inherent to the use of
questionnaires in scientific studies. Other factors to consider are the predominance
of men in sports in Brazil, the disregard concerning injuries or associated diseases,
and the lack of details of other surgical technical aspects, such as the graft fixation
method, instrumentation, use of adjuvants, among other factors.
Conclusion
Orthopedic and traumatology specialists associated with major-league soccer teams
in Brazil tend to wait one to four weeks after ACL injury to perform the surgical
treatment. They preferably use the arthroscopically-assisted single incision and single-bundle
technique, femoral tunnel perforation through the medial accessory portal, and the
quadruple flexor tendon autograft or the patellar tendon autograft.
The players are allowed unrestricted return to sport after six to eight months of
surgery. The parameter used for allowing the athletes to return to sport is the isokinetic
strength test, and they do not use postoperative functional orthoses.
According to the respondents, more than 90% of players operated for ACL injuries return
to professional sports, with 60 to 90% returning to the same or better level of performance.
Therefore, the present article successfully describes the main surgical practices
and post-surgery management adopted by specialists in this highly-specific population
of patients.
