The American Journal of Sports
Medicine
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Stable Surgical Repair With Accelerated Rehabilitation Versus Nonsurgical Treatment for Acute
Achilles Tendon Ruptures: A Randomized Controlled Study
Nicklas Olsson, Karin Grävare Silbernagel, Bengt I. Eriksson, Mikael Sansone, Annelie Brorsson, Katarina
Nilsson-Helander and Jón Karlsson
Am J Sports Med 2013 41: 2867 originally published online September 6, 2013
DOI: 10.1177/0363546513503282
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Stable Surgical Repair With
Accelerated Rehabilitation
Versus Nonsurgical Treatment
for Acute Achilles Tendon Ruptures
A Randomized Controlled Study
Nicklas Olsson,*y MD, PhD, Karin Grävare Silbernagel,z PT, ATC, PhD,
Bengt I. Eriksson,y MD, PhD, Mikael Sansone,y MD, Annelie Brorsson,y PT, MSc,
Katarina Nilsson-Helander,§ MD, PhD, and Jón Karlsson,y MD, PhD
Investigation performed at the Institute of Clinical Sciences at Sahlgrenska Academy,
Sahlgrenska University Hospital, University of Gothenburg, Mölndal, Sweden
Background: The optimal treatment for acute Achilles tendon ruptures is still a subject of debate. Early loading of the tendon is
a factor that has been shown to be beneficial to recovery and to minimize complications. The main outcome of previous studies
has been complications such as reruptures and deep infections, without focusing on the functional outcome relevant to the majority of patients who do not experience these complications.
Purpose: To evaluate whether stable surgical repair and early loading of the tendon could improve patient-reported outcome and
function after an acute Achilles tendon rupture.
Study Design: Randomized controlled trial; Level of evidence, 1.
Methods: A total of 100 patients (86 men, 14 women; mean age, 40 years) with an acute total Achilles tendon rupture were randomized to either surgical treatment, including an accelerated rehabilitation protocol, or nonsurgical treatment. The primary outcome was the Achilles tendon Total Rupture Score (ATRS). The patients were evaluated at 3, 6, and 12 months for symptoms,
physical activity level, and function.
Results: There were no significant differences between the groups in terms of symptoms, physical activity level, or quality of life.
There was a trend toward improved function in surgically treated patients; the results were significantly superior when assessed
by the drop countermovement jump (95% CI, 0.03-0.15; P = .003) and hopping (95% CI, 0.01-0.33; P = .040). No reruptures
occurred in the surgical group, while there were 5 in the nonsurgical group (P = .06). There were 6 superficial infections in the
surgically treated group; however, these superficial infections had no bearing on the final outcome. Symptoms, reduced quality
of life, and functional deficits still existed 12 months after injury on the injured side in both groups.
Conclusion: The results of the present study demonstrate that stable surgical repair with accelerated tendon loading could be
performed in all (n = 49) patients without reruptures and major soft tissue–related complications. However, this treatment was not
significantly superior to nonsurgical treatment in terms of functional results, physical activity, or quality of life.
Keywords: Achilles tendon rupture; Achilles tendon Total Rupture Score; ATRS; functional evaluation; rerupture; heel-rise test;
physical activity level; Foot and Ankle Outcome Score; FAOS; EQ-5D
versus immobilization. Recent studies have shown that
major functional deficits exist after an acute Achilles tendon
rupture, with a wide variation between patients.4,25,28,33,47
These deficits appear to be similar irrespective of the
selected treatment.4,25,33,47 Patients can expect a year-long
recovery after an Achilles tendon rupture, and many
patients do not achieve full recovery of strength and function despite extensive rehabilitation. During the past few
years, there has been a shift toward more accelerated rehabilitation and early weightbearing, which appear to produce
There are several alternatives when it comes to the treatment of acute Achilles tendon ruptures, but no consensus
exists regarding the optimal treatment protocol. An Achilles tendon rupture can be treated surgically or nonsurgically, with different alternatives in terms of mobilization
The American Journal of Sports Medicine, Vol. 41, No. 12
DOI: 10.1177/0363546513503282
Ó 2013 The Author(s)
2867
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2868 Olsson et al
The American Journal of Sports Medicine
improved results.23,42,45 These favorable results related to
early mobilization have recently been shown to be independent of surgical or nonsurgical treatment.9,29,45,47
In previous studies,3,19 the success of a treatment has
been measured by the ability to minimize the risk of
reruptures and other serious complications. The rerupture rate is also the primary outcome variable in 2
recently published randomized controlled trials.29,47 Systematic reviews and meta-analyses of randomized controlled trials report rerupture rates of approximately 3%
to 4% after surgical treatment and 10% to 13% after nonsurgical treatment.3,14,19 In more recent studies, these
rates (0%-7%) are, however, lower.2,13,42,47 With current
treatment protocols, rerupture rates are fairly low (with
both surgical and nonsurgical treatments), but many
patients still fail to achieve full recovery. For this reason,
there is a rationale for a shift toward fully restored function with minimal symptoms as the main goal, and functional
variables
and
patient-reported
outcome
measurements might therefore be more appropriate as
the primary outcome.
Early loading of the tendon and early mobilization of the
patient have been shown to be beneficial to recovery.9,24,29,42,45,47 However, most study protocols do not initiate immediate weightbearing or exercises of the ankle until
after 4 to 8 weeks.17,29,45,47 Based on current preclinical studies, mechanical loading appears to be beneficial during the
early stages of tendon healing.1,10,20 To achieve early accelerated tendon loading, we believe that both early weightbearing and early mobilization of the ankle and Achilles tendon
are needed. A flexor tendon rupture in the hand is currently
primarily repaired with stable end-to-end sutures that are
able to tolerate immediate controlled mobilization.22 If this
type of suture technique is used in the repair of the Achilles
tendon, this might allow for the immediate mobilization of
this tendon as well. There is no consensus with regard to
the optimal suture technique in the open repair of acute
Achilles tendon ruptures, even though the Bunnell, Krackow
locking loop, and Kessler techniques are the most frequently
reported.48 The Krackow locking loop technique has superior
strength according to some studies,46,48 while the Bunnell
and Kessler techniques show similar results in another
study.46 When the suture technique in the present study
was selected, we preferred a technique with high resistance
to tensile strength that could be generally performed by
orthopaedic surgeons. We decided to use a technique including both a core suture with a modified Kessler technique and
an epitendinous cross-stitch, as described by Silfverskiold
and Andersson41 in a modified manner, with a double Kessler
technique as a core suture, as recommended by Shaieb and
Singer36 for flexor tendon injuries in the hand.
The purpose of this study was therefore to evaluate
whether early loading of the tendon and range of motion
training could improve patient-reported outcome and function after a total acute Achilles tendon rupture. We
hypothesized that patients treated with a stable surgical
repair and early accelerated tendon loading and range of
motion training would have superior results compared
with nonsurgical treatment with more traditional rehabilitation after an acute Achilles tendon rupture.
MATERIALS AND METHODS
A total of 101 patients with an acute Achilles tendon rupture were included in this randomized controlled study
between April 2009 and October 2010. This study was conducted at 1 center in Sweden.
All patients (age, 18-65 years) with a closed midsubstance
rupture, who attended this center, were included in the
study. The diagnosis was based on medical history and clinical examination (a palpable gap and a positive Thompson
test result44). Patients were excluded if the rupture was older
than 4 days and if they had a prior Achilles tendon rupture
(either side) or other injuries that affected their lower limb
function. Neuromuscular disease, diabetes, peripheral vascular disease, immunosuppressive treatment including systemic cortisone, skin infection or wound, and inability to
attend rehabilitation or evaluations were all exclusion criteria. All the patients were given oral and written information
about the study before randomization. Of the 201 patients
with an Achilles tendon rupture during this period, 101
patients met the inclusion/exclusion criteria and agreed to
participate in the study (Figure 1). The patients were randomized directly after inclusion, and computer-generated
opaque and sealed envelopes were used in the randomization
process. The patients and the treating physician and physical
therapists responsible for treatment and evaluations were
not blinded to treatment group.
One patient was initially included in the study despite
having an ongoing skin infection and was therefore
excluded from the study directly after randomization.
This patient was randomized to surgical treatment.
All patients gave their written informed consent to participate in the study. Ethical approval was obtained from
the regional ethical review board in Sweden. Baseline
characteristics of the patients are shown in Table 1.
Treatment Procedure
Surgical Group. Forty-nine patients were treated surgically by 1 of 10 experienced orthopaedic surgeons using the
*Address correspondence to Nicklas Olsson, MD, PhD, Orthocenter IFK-Kliniken, Arvid Wallgrens Backe 4a, SE-413 46 Göteborg, Sweden (e-mail:
nicklas.olsson@gu.se).
y
Department of Orthopaedics, Institute of Clinical Sciences at Sahlgrenska Academy, Sahlgrenska University Hospital, University of Gothenburg, Mölndal, Sweden.
z
Department of Physical Therapy, University of the Sciences, Philadelphia, Pennsylvania.
§
Department of Orthopedics, Kungsbacka Hospital, Kungsbacka, Sweden.
One or more of the authors has declared the following potential conflict of interest or source of funding: This study was supported by the Swedish
National Center for Research in Sports.
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Vol. 41, No. 12, 2013
Treatment for Acute Achilles Tendon Ruptures
TABLE 1
Patient Baseline Characteristics
201 patients with
Achilles tendon rupture
Excluded based on study criteria
(n=60)
Surgical
Group
Variable
Eligible for inclusion (n=141)
Declined to participate (n=40)
Wanted nonsurgical treatment (n=23)
Wanted surgical treatment (n=10)
Nonspecific reason (n=7)
Randomized (n=101)
Incorrect inclusion (n=1)
Surgical (n=49)
Nonsurgical (n=51)
Partial rerupture (n=1)
Lost to follow-up (n=1)
Follow-up: 3 mo (n=47)
Rerupture (n=4)
Follow-up: 3 mo (n=47)
Rerupture (n=1)
Follow-up: 6 mo (n=47)
Follow-up: 6 mo (n=46)
Patients, n (%)
Age, y
Mean 6 SD
Median (range)
Sex, n (%)
Male
Female
Height, cm
Mean 6 SD
Median (range)
Weight, kg
Mean 6 SD
Median (range)
Body mass index
Mean 6 SD
Median (range)
Injured side, n (%)
Right
Left
Smoker, n (%)
Nonsmoker, n (%)
Nonsurgical
Group
49 (49)
51 (51)
39.8 6 8.9
40 (24-61)
39.5 6 9.7
39 (20-63)
39 (80)
10 (20)
47 (92)
4 (8)
P Valuea
.74
.09
.43
179 6 8.5
180 (164-200)
179 6 7.5
179 (160-195)
87.2 6 13.0
89 (55-110)
82.0 6 10.8
81 (63-112)
.036
.037
27.1 6 3.5
26.2 (20-39)
25.7 6 2.8
25.7 (20-34)
.10
25
24
4
45
(51)
(49)
(8)
(92)
35
16
5
46
(69)
(31)
(10)
(90)
1.00
a
Boldface indicates significant difference.
Lost to follow-up (n=1)
Lost to follow-up (n=4)
Follow-up: 12 mo (n=43)
2869
Follow-up: 12 mo (n=45)
Figure 1. Flow diagram for the study.
same standardized technique. Surgery was performed in
all patients under local anesthesia. Prophylactic antibiotics (cloxacillin) and prophylaxis against deep vein thrombosis (dalteparin natrium) were given because of the high
risk of deep venous thrombosis.32 Patients were operated
on in the prone position without a tourniquet. A posteromedial skin incision was made over the rupture site, and
the paratenon was then carefully identified before further
incision. The tendon was repaired end to end using core
suturing with 2 strong semiabsorbable sutures (No. 2
Orthocord, DePuy Mitek, Norwood, Massachusetts) and
a modified Kessler technique.18 The double Kessler locking
loop was carefully placed away from the rupture site and
sutured in healthy tendon to achieve the greatest stability.
The foot was placed in plantar flexion to close the gap in
the tendon. Care was taken not to overtension the tendon
with a maximum plantar flexion of 20° to suit the brace.
A running circumferential suture was used with absorbable sutures (No. 0 Polysorb, Tyco, Norwalk, Connecticut),
using an epitendinous cross-stitch technique described by
Silfverskiold and Andersson41 to reinforce the core sutures
(Figure 2). The paratenon was then carefully repaired with
absorbable No. 3-0 Polysorb and continuous No. 2-0 Polysorb subcutaneous sutures. Interrupted nylon sutures
were used in the skin layer to ensure meticulous wound
closure. No cast was used, and the ankle was postoperatively immobilized in a pneumatic walker brace (Aircast
XP Diabetic Walker, DJO, Vista, California), including 3
heel pads that produce a plantarflexion angle of approximately 22°. A soft 5-mm inner sole was used to compensate
for the somewhat stiff heel pads. Patients were allowed full
weightbearing, which was encouraged from the first postoperative day.
Three experienced physical therapists supervised the
postoperative care and rehabilitation of all the patients.
Early active rehabilitation started 2 weeks postoperatively
and included both range of motion and strength training
following a standardized protocol (see Appendix 1, available online at http://ajsm.sagepub.com/supplemental).
The surgical group was mobilized in the brace for 6 weeks.
Nonsurgical Group. Fifty-one patients were included in
the nonsurgical group. Treatment started immediately
after randomization, using the same brace as in the surgical group, including the 3 heel pads. Full weightbearing
was allowed and encouraged from the beginning in the
same manner as for the surgical group. This treatment
group used another standardized protocol (see Appendix
2, available online) and was immobilized in the brace for
8 weeks. A similar nonoperative treatment has previously
been described by Ingvar et al.13
Follow-up Evaluation
A clinical follow-up examination was performed at the
orthopaedic department, primarily by the first author
(N.O.), at 2, 6, and 26 weeks in the surgical group and
at 8 and 26 weeks in the nonsurgical group. The focus
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2870 Olsson et al
The American Journal of Sports Medicine
functional tests, patient-reported outcomes, and physical
activity levels measured at 3, 6, and 12 months.
Patient-Reported Outcome and Physical Activity
Before functional testing, the patients answered 4 different
questionnaires. These have been used in previous studies in
this patient group and have been shown to be reliable and
valid.11,12,31,34 To evaluate injury-specific patient-reported
outcome, we used the ATRS.16,31 The ATRS ranges from
0 to 100; a lower score indicates greater limitations to physical activity and more symptoms. The Physical Activity
Scale (PAS) questionnaire12 was used to evaluate the activity level. A score of 1 is equal to no physical activity,
whereas a score of 6 equals heavy physical exercise several
times a week. For a foot and ankle perspective, 3 subscales
of the Foot and Ankle Outcome Score (FAOS)34 were used:
activities of daily living (ADL), function in sport and recreation, and foot- and ankle-related quality of life (QOL). All
the subscales of the FAOS range from 0 to 100. A score of
0 indicates a high degree of foot- and ankle-related symptoms, whereas 100 indicates no symptoms. General
health-related quality of life was measured by the EuroQol
Group’s questionnaire (EQ-5D).5,11 An EQ-5D score of 0 is
considered to be the worst imaginable health state and
a score of 1.00 the best imaginable health state.
At the time of inclusion (baseline), the EQ-5D and PAS
were assessed. During the follow-up at 3, 6, and 12 months,
all the scores were used.
Figure 2. Illustration of the suture technique used in the trial.
Functional Evaluation
at this time was to evaluate and register any clinical
complications. If a rerupture occurred, the diagnosis
was based on the clinical examination, evaluating
whether there was a palpable tendon gap, loss of plantarflexion strength, and a positive Thompson test result.
Magnetic resonance imaging (MRI) was used if the clinical examination was nonconclusive. Wound- and skinrelated disturbances and infections were diagnosed by
clinical signs and, if suitable, microbiological samples.
Nerve disturbances were diagnosed by case history and
clinical examination in the event of a loss or partial
loss of sensibility.
The patients were evaluated using patient-reported outcomes and functional evaluation tests on 3 occasions at
a mean 6 standard deviation (SD) of 12 6 0.7, 28 6 2.1,
and 56 6 4.3 weeks by the same physical therapist at
our testing laboratory. The evaluating physical therapist
was not involved in the treatment of the patients. All
patient-reported outcome data in this study were collected
using a web-based protocol. This minimized the risk of
missing values and lost data.
Outcomes
The primary outcome in this study was the Achilles tendon
Total Rupture Score (ATRS).31 Secondary outcomes
included reruptures and other complications as well as
The functional evaluation protocol consisted of 2 different
jump tests, 2 different strength tests, and 1 muscular
endurance test, and the MuscleLab (Ergotest Technology,
Oslo, Norway) measurement system was used for the evaluations. This testing protocol using the MuscleLab unit
was performed exactly as previously described in the literature.29,38,39 The tests have been shown to be reliable and
valid38,39 and have been used in evaluating outcome after
Achilles tendon ruptures.29,30,39 All evaluations were performed by the same experienced physical therapist. All
the patients were given standardized instructions and
warm-up, and athletic footwear was standardized.
The jump tests comprised a drop countermovement
jump (drop CMJ) and hopping. For the drop CMJ, the
patients started by standing on 1 leg, on a 20 cm–high
box, then jumped down onto the floor, and directly afterward performed a maximum vertical jump.38 For data
analysis, the maximum jumping height (in cm) was used.
Hopping was a continuously rhythmic jump similar to
skipping performed on 1 leg at a time.38 The mean hopping
height (in cm) and the hopping quotient (flight time/
contact time) were used for data analysis.
The strength tests were a concentric heel rise and an
eccentric-concentric heel rise performed while standing
on 1 leg in a weight machine.38 The best trial, that is,
the trial with the highest power (in W), for each weight
was used for data analysis.
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Vol. 41, No. 12, 2013
Treatment for Acute Achilles Tendon Ruptures
Muscular endurance was tested using a single-leg
standing heel-rise test.39 This was performed on 1 leg at
a time with the participant standing on a box with an
incline of 10°. A metronome was used to maintain the frequency of 30 heel rises a minute. The participant was
instructed to go as high as possible on each heel rise and
was asked to perform as many as possible. The test was
terminated when the patient stopped, was unable to maintain the frequency, or did not perform a proper heel rise
(minimum height of 2 cm). The numbers of heel rises, as
well as the height of each heel rise and the total work
(body weight 3 total distance; in J), were used for data
analysis. To document the heel-rise height, the maximum
height obtained during the test was used for evaluation.
Statistical Analysis
Power calculations were based on data from a previous
study in which the ATRS value at 12 months had an SD
of 15.39 The effect size was set at 10, based on published
data of a minimal detectable change of 6.8.6 The power
was set at 85% and the type I error at 5%. Power analysis
gave us a sample size of 41 in each group.
The limb symmetry index (LSI) was defined as the ratio
between the involved limb score and the uninvolved limb
score, expressed as a percentage (involved/uninvolved 3
100 = LSI). Because the LSI represents the clinical relevance of the functional results, we used these data when
comparing the 2 treatment groups. The absolute values
are used when measuring the recovery of function in
each group and also the comparison over time.
All the data were analyzed using IBM SPSS Statistics
(version 20.0, IBM Corp, Armonk, New York). For descriptive
statistics, we report the questionnaire results as both median
(range) and mean 6 SD. The reason for reporting the results
in both ways is that, as these are ordinal data, we want to use
the median (range), but as results based on these questionnaires are often reported as the mean 6 SD in other articles,
we have included that as well. The level of significance was
set at P \ .05. For this study, we used nonparametric statistics in the evaluation of the questionnaires. The MannWhitney U test was used to compare 2 groups of patients.
The x2 test was used for dichotomous variables, and when
the sample size was small, the Fisher exact test was used.
The Wilcoxon signed-rank sum test was used to compare
paired variables. An analysis of the functional data revealed
normal distribution, and parametric statistics were therefore
used when evaluating these data. The independent t test was
used to compare the 2 groups, and to compare side-to-side differences, the paired t test was used.
RESULTS
Patient-Reported Outcome and Physical Activity
The surgical group had a median ATRS of 44 (range, 11-86;
mean, 43 6 20) at the 3-month evaluation, a median ATRS
of 75 (range, 0-99; mean, 70 6 23) at the 6-month evaluation, and a median ATRS of 89 (range, 0-100; mean, 82 6
2871
20) at the 12-month evaluation. The nonsurgical group
had a median ATRS of 33 (range, 6-73; mean, 35 6 14) at
the 3-month evaluation, a median ATRS of 73 (range, 3397; mean, 70 6 19) at the 6-month evaluation, and
a median ATRS of 90 (range, 2-100; mean, 80 6 23) at
the 12-month evaluation. There were no statistically significant differences between the 2 treatment groups at 3,
6, and 12 months as evaluated by the ATRS, and both
groups improved significantly over time (P \ .001) at the
3-, 6-, and 12-month evaluations (Table 2).
The median preinjury PAS score was 4 (range, 2-6;
mean, 3.9 6 1.1) in the surgical group and 4 (range, 2-6;
mean, 4.2 6 1.0) in the nonsurgical group. There were no
significant differences in physical activity level between
the groups’ preinjury level or at 6 and 12 months (Table
2). Furthermore, no significant differences were found in
physical activity level when comparing the preinjury level
with the level at 12 months either in the surgical group
(P = .78) or in the nonsurgical group (P = .23).
At the 3-month evaluation, the median FAOS ADL subscores were 81 (range, 13-100; mean, 78 6 17) in the surgical group and 79 (range, 40-97; mean, 77 6 13) in the
nonsurgical group, with no significant difference between
the groups (P = .42). At the same time, the median FAOS
sport and recreation subscore was 30 (range, 0-85; mean,
34 6 22) in the surgical group and 30 (range, 0-65; mean,
28 6 17) in the nonsurgical group, with no significant differences between the groups (P = .24). The FAOS ADL and
FAOS sport and recreation subscores improved significantly (P \ .01) over time in both the surgical and nonsurgical groups at the 3-, 6-, and 12-month evaluations, except
for the FAOS ADL subscore in the surgical group between
6 and 12 months (P = .10) (Table 2).
Quality of Life
The median FAOS QOL subscore was 44 (range, 0-81;
mean, 45 6 18) at 3 months in the surgical group and 38
(range, 6-69; mean, 39 6 15) in the nonsurgical group,
with no significant differences between the groups (P =
.10). The FAOS QOL subscores at the 6- and 12-month evaluations are shown in Table 2. The scores improved significantly over time between 3, 6, and 12 months (P \ .001).
The median preinjury level according to the EQ-5D was
1.00 (range, 0.52-1.00; mean, 0.95 6 0.11) in the surgical
group and 1.00 (range, 0.26-1.00; mean, 0.95 6 0.13) in
the nonsurgical group. At 12 months, the median EQ-5D
value was 1.00 (range, 0-1.00; mean, 0.91 6 0.17) in the
surgical group and 1.00 (range, 0.52-1.00; mean, 0.90 6
0.13) in the nonsurgical group (Table 2). There were no significant differences (P = .30) between the 2 treatment
groups at the 12-month evaluation, but there was a significant decrease in the EQ-5D value in both the surgical (P =
.03) and nonsurgical (P = .03) groups at the 12-month evaluation compared with the preinjury value.
Functional Tests
Surgical Versus Nonsurgical Group at 3, 6, and 12
Months. Table 3 shows the LSI values for the surgical
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2872 Olsson et al
The American Journal of Sports Medicine
TABLE 2
Results of the 6- and 12-Month Postinjury Evaluationsa
6-Month Evaluation
Surgical (n = 47)
ATRS
Mean 6 SD
Median (range)
FAOS ADL
Mean 6 SD
Median (range)
FAOS sport and recreation
Mean 6 SD
Median (range)
FAOS QOL
Mean 6 SD
Median (range)
PAS
Mean 6 SD
Median (range)
EQ-5D
Mean 6 SD
Median (range)
Nonsurgical (n = 46)
12-Month Evaluation
P Value
Surgical (n = 43)
Nonsurgical (n = 45)
.63
70 6 23
75 (0-99)
70 6 19
73 (33-97)
90 6 17
96 (24-100)
92 6 10
96 (60-100)
68 6 24
70 (0-100)
69 6 19
70 (25-100)
63 6 20
63 (0-100)
61 6 16
63 (25-94)
3.8 6 1.0
4 (1-6)
3.8 6 1.1
3 (2-6)
.68
82 6 20
89 (0-100)
80 6 23
90 (2-100)
94 6 14
99 (21-100)
94 6 11
100 (54-100)
83 6 20
90 (0-100)
83 6 21
90 (15-100)
75 6 21
75 (0-100)
77 6 21
81 (25-100)
4.0 6 1.1
4 (1-6)
4.0 6 1.0
4 (2-6)
.59
.37
.83
.70
.54
.51
.59
.85
.24
0.88 6 0.18
1.00 (0.08-1.00)
0.86 6 0.13
0.82 (0.62-1.00)
P Value
.30
0.91 6 0.17
1.00 (0-1.00)
0.90 6 0.13
1.00 (0.52-1.00)
a
ADL, activities of daily living; ATRS, Achilles tendon Total Rupture Score (0-100); EQ-5D, EuroQol Group’s general health-related quality of life (0-1.00); FAOS, Foot and Ankle Outcome Score (0-100); PAS, Physical Activity Scale (1-6); QOL, foot- and ankle-related quality of
life.
and nonsurgical groups at the 6- and 12-month evaluations. The LSI values were consistently higher in the surgical group compared with the nonsurgical group, except
for concentric and eccentric power at 6 months (Table 3),
but these differences were nonsignificant, except for hopping and the drop CMJ at 12 months (Table 3).
Injured Versus Uninjured Side. The recovery of function
in both groups and each test variable is presented in absolute values in Appendix 3 (available online). A comparison
of the injured with the uninjured side in Appendix 3 shows
that all the values were significantly (P \ .001) higher on
the uninjured side at 6 months. At 12 months, the injured
side had improved in the surgical group, and there were no
significant differences in hopping and concentric power
when comparing the injured and uninjured sides (P =
.24-.76). In the nonsurgical group, the injured side also
improved in the hopping test, and there were no significant
differences between the sides (P = .07-.08).
Complications
There were no reruptures in the surgical group. However,
1 surgically treated patient sustained a partial rerupture
during a fall on level ground 3 weeks after the last day of
immobilization. A clinical examination and MRI were
used to diagnose this partial rerupture. The tendon healed
after additional treatment with 8 weeks in a brace. This
long time in a brace was mainly because the patient was
highly noncompliant with the mobilization instructions.
Five patients (10%) in the non–surgically treated group
sustained a rerupture, all of which occurred between 5
and 12 weeks after the initial injury. One patient was
noncompliant during the brace treatment, 1 patient sustained a rerupture when walking on level ground, 1 patient
had a new trauma during a fall from stairs, 1 patient had
a rerupture at the functional evaluation during the heelrise test at 12 weeks, and the last patient had clinical signs
of a nonhealed tendon (palpable gap and positive Thompson test result) at the end of immobilization. All 5 patients
were surgically treated with augmentation as previously
described by Nilsson-Helander et al,30 and the diagnosis
was confirmed during surgery.
There was a numerical difference in the rerupture incidence between the 2 treatment groups (P = .06). The patients
who sustained a rerupture were all tested at 6 and 12 months
after the rerupture (see Appendix 4, available online) using
the same test protocol as those who did not sustain a rerupture. After the treatment with augmented surgery and rehabilitation, there was no significant difference between the
patients who sustained a rerupture and patients with no
rerupture in all the functional tests except for heel-rise
height at 6 months (P = .011), which demonstrated that
the mean results were higher for patients who sustained
a rerupture (LSI, 87% 6 11%) compared with those who
did not sustain a rerupture (LSI, 69% 6 15%).
Deep vein thrombosis occurred in 1 patient (2%) in the
surgical group and in 2 patients (4%) in the nonsurgical
group. The diagnosis was confirmed using the Doppler
ultrasound technique. Six patients (12%) in the surgical
group were defined as having a superficial wound infection, and they all healed with antibiotics and wound dressings, even though 2 of these patients were treated only on
suspicion of a superficial infection. One patient in the surgically treated group had persistent partial sural nerve
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Vol. 41, No. 12, 2013
Treatment for Acute Achilles Tendon Ruptures
2873
TABLE 3
Functional Test Performance (Limb Symmetry Index) Scores at 6 and 12 Months After Injurya
6-Month Evaluation
Test
Hopping
No. of patients
Mean 6 SD
Range
Hopping (plyometric quotient)
No. of patients
Mean 6 SD
Range
Drop CMJ
No. of patients
Mean 6 SD
Range
Concentric power
No. of patients
Mean 6 SD
Range
Eccentric power
No. of patients
Mean 6 SD
Range
Heel-rise repetitions
No. of patients
Mean 6 SD
Range
Heel-rise height
No. of patients
Mean 6 SD
Range
Heel-rise work
No. of patients
Mean 6 SD
Range
Surgical
Nonsurgical
42
82 6 36
0-173
42
76 6 33
0-115
42
82 6 35
0-153
42
78 6 32
0-114
45
81 6 21
0-112
45
74 6 12
49-98
47
75 6 34
0-147
46
78 6 58
0-380
47
59 6 21
0-104
46
61 6 33
0-147
47
89 6 27
22-193
46
81 6 24
24-122
47
72 6 15
40-107
46
66 6 15
35-98
47
65 6 23
7-127
46
56 6 22
8-107
12-Month Evaluation
P Value
b
Surgical
Nonsurgical
37
103 6 36
0-200
43
86 6 36
0-147
37
101 6 29
0-174
43
88 6 32
0-127
40
91 6 15
70-131
43
82 6 13
59-123
40
95 6 39
40-200
44
84 6 36
34-216
40
83 6 29
51-170
43
81 6 35
0-169
41
93 6 17
52-138
45
90 6 17
26-120
41
80 6 15
46-116
45
79 6 16
28-105
41
76 6 19
21-120
45
71 6 19
7-105
.43
P Valueb
.040
.66
.06
.06
.003
.78
.17
.62
.84
.12
.34
.06
.93
.09
.20
a
Limb symmetry index values are expressed as a percentage and calculated as the involved limb score/uninvolved limb score 3 100. Drop
CMJ, drop countermovement jump.
b
Boldface indicates significant difference.
disturbance. The brace caused minor temporary problems
with macerated skin and pain- and pressure-induced nerve
disturbances in 13 surgically treated patients (26%) and in
2 (4%) nonsurgically treated patients.
DISCUSSION
The results of the present study demonstrate that surgical
repair with a stable suture technique and accelerated rehabilitation, including immediate weightbearing, range of
motion, and strength training, is a well-tolerated method
without any major soft tissue–related complications. However, there is no conclusive evidence that this treatment
was superior to nonsurgical treatment with immediate
weightbearing in a brace when comparing functional
results.
There were no significant differences in the ATRS
between surgical and nonsurgical treatments at the 6-
and 12-month evaluations (Table 2). The ATRS is the primary outcome variable in the present study, and we were
therefore unable to confirm our hypothesis. The ATRS nevertheless shows a tendency toward a favorable result for
surgical treatment at 3 months compared with nonsurgical
treatment, even though this was not statistically significant. Nilsson-Helander et al29 reported similar results in
a previous study. However, the fact that neither group in
this study achieved full recovery in patient-reported outcome scores at the 12-month follow-up is of greater importance, and this is similar to what has been reported in
previous studies.29,47
We were unable to find any differences between surgical
and nonsurgical treatments in physical activity level, and
both groups had returned to their previous activity level
by 12 months after injury. Moller et al26 showed in both
surgical and nonsurgical groups that 46% of patients did
not resume their preinjury level of sports, and Cetti
et al7 have also reported similar results in which only
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2874 Olsson et al
The American Journal of Sports Medicine
57% of surgically treated and 29% of nonsurgically treated
patients resumed their previous level of sports activity.
Nilsson-Helander et al29 reported significantly reduced
physical activity levels in both surgical and nonsurgical
treatment groups at 12 months. In contrast, this study
revealed no significant differences in physical activity level
when comparing the preinjury and 12-month data.
Whether early weightbearing and exercises or any other
aspect of the current rehabilitation protocol might have
a positive effect on the return to physical activity needs
to be further investigated.
In the present study, we used 2 different scores to evaluate measurements of quality of life: the FAOS QOL and
EQ-5D. We were unable to find any differences between
the treatment groups in terms of quality of life scores as
measured by either of these. The 2 scores describe different
properties of quality of life, and the more general quality of
life score, the EQ-5D, showed significantly lower values at
12 months after injury compared with the preinjury values. The FAOS QOL subscores at 12 months, with
a mean of approximately 75 for both groups, also indicate
that ankle- and foot-related quality of life is negatively
affected. To summarize, this indicates that an Achilles tendon rupture does not simply affect the lower limb but also
affects the patient’s general quality of life.
All LSI variables in the surgically treated group were
numerically higher when assessed by the functional evaluation tests including jump, power, and endurance at the 12month follow-up compared with the nonsurgical group,
although statistically significant differences were verified
only for hopping and the drop CMJ only (Table 3). Favorable
functional results after surgical treatment at 12 months have
also been reported in a study by Nilsson-Helander et al.29 In
that study, the same functional evaluation was used, and the
absolute values in the different tests were 4% to 11% higher
in favor of surgical treatment compared with nonsurgical
treatment, but with a statistically significant difference
only in the heel-rise work test. We report approximately
the same results in the 2 studies, indicating a possible advantage for surgical treatment. To verify this, a larger study population is required to determine whether surgical treatment
is indeed superior when it comes to regaining function.
In the present study, there were no reruptures in the
surgically treated group, while there were 5 in the nonsurgically treated group (P = .057). Despite the difference in
numbers, this is not statistically significant, but it could
have been interpreted as a type II error. Most studies, apart
from the one by Moller et al,26 have not shown any statistically significant difference between surgical and nonsurgical treatment in terms of the rerupture rate. Pooled
statistical analyses3,14,19,47 have demonstrated a significantly reduced risk of reruptures in surgically treated Achilles tendon ruptures, but these meta-analyses did not
conclude that one treatment is superior to the other based
on the total number of complications and other evaluations.
In many of the tests, function in the injured leg was significantly reduced compared with the uninjured leg at 12
months after injury (Table 3), and other studies have presented similar results. It is important to understand why
not all patients regain full function to make it possible to
further optimize the treatment. Elongation of the tendon
might be one reason for the impaired function of the injured
leg. Kangas et al15 concluded that patients with less tendon
elongation achieved a better clinical outcome, and 2 studies
have shown a separation of tendon ends at 4 months after
injury in surgically treated Achilles tendon ruptures.27,35
Silbernagel et al40 have recently described a method for
measuring tendon length and found a significant correlation
between tendon elongation and deficits in heel-rise height
after an Achilles tendon rupture. If this decrease in heelrise height is indicative of increased tendon length, this
could be an important reason for the deficits in function in
our study. The correct length of the tendon is probably easier to achieve by surgical treatment compared with nonsurgical treatment, and this could explain the difference in
function in favor of surgical treatment. However, further
studies are needed to determine the relevance of tendon
length and conclude whether this could predict the outcome.
The 5 patients who sustained a rerupture and were
treated with the augmented surgical technique had similar
functional results at both 6 and 12 months after the rerupture compared with the patients with no reruptures at 6
and 12 months after injury. There is therefore no reason
to believe that these patients have inferior end results.
From this perspective, a rerupture might not produce an
inferior end result, apart from a prolonged period of treatment and additional surgery. The clinical experience is
that this ‘‘loss of time’’ will have varying implications in
individual patients mainly because of different demands
in sports and work but also because of a mismatch in
expectations regarding healing time.
The study protocol in the present study, with immediate
treatment in a brace to facilitate full weightbearing, might
have some disadvantages. Willits et al47 used the same
brace, starting after 2 weeks, when the surgical wound
had healed and had 4 superficial infections and 1 deep infection in their group of 72 patients treated with open repair. A
pooled analysis by Khan et al19 revealed 7 infections in 173
patients treated with open surgical techniques. The rate in
the present study is higher, and one reason for this might be
a stretching of the surgical wound due to immediate weightbearing and the somewhat tight environment for the surgical wound inside the brace. Metz et al24 also reported a high
incidence of skin-related complications because of the tight
environment in a continuously worn brace. The different
rates of infection might also be caused, to some extent, by
different definitions of postoperative infection.
Previous clinical studies23,24,43,47 have shown favorable
results after protected weightbearing. Human and animal
models1,21 have shown better results when the tendon is
loaded during the healing process. The American Academy
of Orthopaedic Surgeons (AAOS) guidelines8 also recommend early protected postoperative weightbearing. To
our knowledge, Costa el al9 and Metz et al24 are the only
previous randomized controlled trials with a rehabilitation
protocol with immediate full weightbearing. In the present
study, both groups had a treatment protocol that promoted
immediate weightbearing, but in contrast to the other
studies, this study also included controlled range of motion
and strength training early in the surgical group. The
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Vol. 41, No. 12, 2013
Treatment for Acute Achilles Tendon Ruptures
results of this study support a shift toward early loading of
the tendon.
The study has certain limitations. First, there is the limitation of not having any biomechanical studies of the
suture technique, and we instead used information in the
literature to construct our technique.37 Second, the surgically treated group had both an accelerated rehabilitation
protocol and surgery as different factors compared with
the nonsurgical group. It is possible to argue that it is not
known which factor makes the difference, but we consider
that surgery is necessary for this accelerated rehabilitation
protocol, and we therefore regard surgery and accelerated
rehabilitation as 2 parts of the same unit. Third, this study
is not blinded. When the study began, only 1 experienced
physical therapist was available, and this made correct
blinding complicated. Inspecting both the scar and tendon
and issuing instructions about the shoes would not have
been possible for one person. Fourth, the instructions for
the patients stated that full weightbearing was allowed
and encouraged from the first day, but we have no measurements of how much the patients actually performed weightbearing. We believe that future studies of early mobilization
and weightbearing should include measurements of this
kind. Finally, it is possible that we need to consider a possible type II error, which is important when analyzing the
superiority of either treatment in terms of function,
patient-reported outcomes, and reruptures, as discussed
above. This leads to the conclusion that larger randomized
controlled studies are needed.
Clinically, the findings in the present study show that this
type of surgical treatment with accelerated rehabilitation
produced no reruptures and that immediate weightbearing
is well tolerated in spite of minor complications. This can
be regarded as a safe form of treatment in patients who prioritize swift rehabilitation and therefore wish to minimize
the risk of a second treatment period and accept the possible
downside of surgical treatment. Our data do not support any
treatment as being superior to the other, but it is our belief
that the choice of treatment should be decided on an individual basis, and it is possible to speculate that this protocol of
stable repair with accelerated rehabilitation is preferable
for selected highly demanding patients because of the tendency toward favorable results in this group.
CONCLUSION
The results of the present study demonstrate that our stable surgical repair with accelerated tendon loading could
be performed in all (n = 49) patients without reruptures
and major soft tissue–related complications. However,
this treatment was not significantly superior to nonsurgical treatment in terms of functional results, physical activity, or quality of life.
ACKNOWLEDGMENT
The authors thank Lotta Falkheden Henning, Agneta
Klang Björkeryd, Alexander Gustavsson, Margareta
2875
Stärnertz, Elsa Giselsson, and Agneta Dubár-Karlsson
for data collection and their help in treating the patients.
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