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BMC Musculoskeletal
Disorders
Outcomes ofoperative andnonoperative
management ofmyotendinous Achilles tendon
ruptures: asystematic review
Darius L. Lameire1*, Luca Ramelli2, Mansur Halai1,3, David Wasserstein1,4,5,6 and Sam Si‑Hyeong Park1,4,6
Abstract
Background Achilles tendon ruptures are the most common lower extremity tendinous rupture. While there
has been extensive research into the management of mid‑substance Achilles tendon ruptures, there is a paucity of lit‑
erature on the management of myotendinous Achilles tendon ruptures.
Methods The aim of this systematic review is to compile all available literature on the treatment of myotendinous
Achilles tendon tears. A systematic search of Web of Science, Embase, and Medline databases was performed for all
studies published from database inception to April 13, 2024. All publications addressing the treatment of myotendi‑
nous Achilles ruptures of all levels of evidence were included. The PRISMA Checklist guided the reporting and data
abstraction. Descriptive statistics are presented.
Results A total of five studies with 70 patients were included for analysis. Sixty‑seven patients underwent non‑
operative management with an average age ranging from 40.8 to 51.0 years. Three patients underwent operative
management with ages of 16, 36, and 39. The majority of patients tore their Achilles tendon during sports. For nonop‑
eratively treated patients, one group underwent immobilization for a total of 6 weeks and one study treated patients
with functional rehabilitation. All patients were able to perform a single heel‑raise, had good reported strength,
and returned to work or sport. Nonoperative patients reported statistically significant improvements in subjective out‑
comes and high rates of satisfaction.
Conclusion Both nonoperative and operative management of myotendinous Achilles tendon ruptures demon‑
strated good outcomes after injury, although there is a limited amount of literature on this topic. Given that nonop‑
erative treatment appears to yield good strength and return to activity, it may be preferred for the majority of patients.
Operative management may be indicated in high level athletes. Imaging to determine the exact location of injury,
quality of remaining tendon, and gap distance may further aid when considering treatment options. Higher level
evidence studies are required to determine the optimal treatment of myotendinous Achilles tendon ruptures.
Level ofevidence IV; Systematic review of Level IV‑V studies.
Keywords Achilles, Myotendinous, Musculotendinous, Tear, Rupture, Treatment, Operative, Nonoperative
*Correspondence:
Darius L. Lameire
darius.lameire@mail.utoronto.ca
Full list of author information is available at the end of the article
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Lameireetal. BMC Musculoskeletal Disorders (2025) 26:71
Introduction
Achilles tendon ruptures are the most common lower
extremity tendinous ruptures experienced by patients [1].
If not diagnosed and managed in a timely manner, this
injury can result in significant morbidity and an inability
to return to full athletic activity long-term [1]. e injury
most commonly occurs in patients between the ages of
30 and 60 who participate in recreational sports on a spo-
radic basis (“the weekend warrior”) [2]. e sports that
are most commonly associated with acute Achilles ten-
don ruptures include running, dancing, gymnastics, ten-
nis, soccer, basketball, and American football [3]. ese
sports often require movements involving sudden forced
plantar flexion of the foot, which is a common mecha-
nism of Achilles tendon rupture [4]. Other mechanisms
of injury include direct trauma and chronic degenerative
tendinopathy. An increased risk of Achilles tendon rup-
tures has also been shown in patients with a history of
prolonged corticosteroid use, overexertion, fluoroqui-
nolone antibiotics, oral bisphosphonates, diabetes, end-
stage renal disease, and hyperparathyroidism, although
these ruptures tend to be more atraumatic in nature [3,
5–8].
e Achilles tendon typically ruptures two to six
centimetres above the calcaneal insertion in the mid-
substance of the tendon, as this area is where the blood
supply to the tendon is diminished [9]. However, the
next most common location of Achilles tendon rupture
is at the myotendinous junction (MTJ, also known as the
musculotendinous junction) [10]. e anatomic myoten-
dinous junction is considered the zone of transition from
the soleus to the Achilles tendon proper distally (as it
combines with the aponeurosis of the two heads of the
gastrocnemius) [11, 12]. e proportion of Achilles ten-
don ruptures occurring at the MTJ is unclear; however,
one retrospective study that examined over 500 Achilles
tendon rupture patients found that 6.7% of patients had a
tear at the MTJ [13]. ese MTJ Achilles tendon injuries
have been reported to have increased calf swelling due to
bleeding from the muscular portion of the tear [10], and
are generally more difficult to diagnose clinically than
their mid-substance counterparts. As such, radiographic
evidence via ultrasound or MRI is often performed to
confirm the diagnosis if an MTJ tear is suspected [7].
ere is often debate surrounding the potential ben-
efits versus risks of surgical intervention for Achilles
tendon ruptures. Many studies have demonstrated good
functional results and patient satisfaction with both non-
operative and operative modalities [8, 14–17]. Although
conservative management has historically shown a
higher re-rupture rate when compared to surgical inter-
ventions, the advancement of post-operative rehabilita-
tion programs has decreased this risk significantly [16,
17]. However, the evidence on management of Achilles
tendon ruptures has focused primarily on mid-substance
tendon ruptures, and to our knowledge, no previous
randomized controlled trials have reported on myoten-
dinous Achilles tendon tears confirmed with advanced
imaging or intraoperatively. As such, the optimal man-
agement of MTJ Achilles tendon ruptures is still not
clear. e purpose of this systematic review is to compile
all available literature on thetreatment of myotendinous
Achilles tendon tears.
Methods
is systematic review focused on all treatments of diag-
nosed acute myotendinous junction Achilles tendon rup-
tures. is review followed the Preferred Reporting Items
for Systematic Reviews and Meta-Analysis (PRISMA)
guidelines [18].
Comprehensive search strategy
e databases of Web of Science, Embase, and Medline
were searched systematically by two reviewers (D.L.L.
and L.R.) for all studies published before April 13, 2024.
A separate manual search was also completed to ensure
no subsets of myotendinous tears were reported in stud-
ies focusing on all Achilles tendon tears. All publications
assessing the management of myotendinous or musculo-
tendinous junction Achilles ruptures/tears were included
(complete search strategy can be found in Supplemen-
tary Digital Content [SDC] 1). Myotendinous and mus-
culotendinous were used synonymously. e inclusion
criteria consisted of: (1) diagnosed rupture/tear of the
Achilles at the myotendinous junction (MTJ); (2) rup-
ture/tear diagnosed by imaging or identified intra-oper-
atively; (3) skeletally mature patients aged 16years old
or older; (4) acute management within 4weeks of injury;
(5) English language publications; and (6) all levels of evi-
dence including case reports with single patients. e
exclusion criteria consisted of: (1) Intrasubstance/mid-
substance or insertional Achilles tendon ruptures/tears;
(2) chronic Achilles tendon tears; (3) surgical technique
publications without clinical outcomes, and (4) publi-
cations without any clinical outcomes reported. Given
the wide anatomical variability between individuals in
regards to the distance from the myotendinous junction
to the calcaneal tuberosity, only studies that specifically
reported myotendinous junction tearsbased off imaging
or intraoperatively (not based on distances from the cal-
caneal tuberosity) were included [11, 19].
Study screening
All study titles and abstracts were independently assessed
by two authors (D.L.L. and L.R.) and included studies
were advanced to full text review. Any disagreements
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Lameireetal. BMC Musculoskeletal Disorders (2025) 26:71
were resolved by the senior author (S.S.P). e level of
agreement between authors was evaluated by calculating
a Kappa (κ) score [20]. e quality of studies was assessed
using the Methodological Index for Non-randomized
Studies (MINORS) [21]. For comparative studies, the
maximum score is 24. For noncomparative studies, the
maximum is 16. Scores for poor, fair, good, or excellent
were determined by previously reported ranges [22].
Data abstraction
Google Sheets (Alphabet, Inc) was used to abstract
the data using predetermined tables by one reviewer,
and another reviewer evaluated all abstracted data.
Abstracted data included: number of patients, patient
characteristics (age, gender, etc.), study information (title,
authors, publication year, etc.), method of diagnosis of
myotendinous junction Achilles tendon ruptures, follow-
up period, treatment specifics in regards to operative and
nonoperative management, and clinical outcomes. Level
of evidence (LOE) was reported as specified by authors,
or if not stated, based on the American Academy of
Orthopaedic Surgeons (AAOS) Evidence-Based Practice
Committee guidelines [23].
Primary outcomes
e primary outcome of interest was to present the cur-
rent management strategies reported for myotendinous
achilles tears and their associated rehabilitation methods.
is included both nonoperative rehabilitation strategies
and operative management options.
Secondary outcomes
e secondary outcomes consisted of: objective out-
comes, rates of Achilles tendon re-rupture, patient
reported outcome measures (PROMs), complica-
tions, and tendon elongation. Objective measures
included heel raise strength, Achilles tendon resting
angle (ATRA), and otherstrength outcomes. Heel raise
strength was reported as the ability to perform the activ-
ity with a single-leg [24]. ATRA is a measure of the rest-
ing angle of the ankle and has been shown to be reliable
in patients with Achilles tendon ruptures [25–27]. As per
Carmont etal., [13] the ATRA is measured as “the angle
between the long axis of the fibula and the line from the
tip of the fibula to the head of the fifth metatarsal, meas-
ured using a standard 30cm goniometer, with the patient
lying prone and both knees flexed to 90 degrees. e rela-
tive ATRA is the difference between the ATRA on the
injured side and the non-injured side.” Additionally, the
heel-rise height index (HRHI) is determined as “patients
perform a single leg heel-rise, and this is compared with
function of the non-injured side to determine a limb sym-
metry index as a percentage" [28]. e heel-rise height is
measured by asking the patient to stand on one leg on a
4cm flat wooden block [13]. A tape measure is taped to
the Achilles tendon so that the 10cm mark is level with
the block [13]. e patient is asked to perform a single
heel-rise and the height raised is measured against the
block” [13].
Patient reported outcome measures (PROMs) included
the Achilles Tendon Total Rupture score (ATRS), the
Foot and Ankle Ability Measure-Sports (FAAM-Sports),
a visual analog scale for pain (VAS Pain), and satisfaction
rates. ATRS is a questionnaire filled out by the patient
with a maximum score of 100, which indicates full func-
tion and no symptoms [29]. e FAAM-Sports is a self-
reported questionnaire that assesses the patient’s ability
to do more difficult tasks deemed essential to sport [30].
e FAAM-Sports scale has an 8-item subscale, with a
minimum score of 0 indicating unable to do any of the
items to a maximum of 100 indicating no difficulty with
any questioned tasks. VAS Pain is determined on a 10cm
scale, with 0 indicating no pain, and 10 indicating excru-
ciating pain. To determine tendon elongation, Carmont
etal. [13] considered it “to be a relative ATRA of more
than ≥ 12° at 12-month evaluation. is relative ATRA
is considered to be consistent with an acutely ruptured
Achilles tendon [27]. e absence of a palpable gap
and an ATRA consistent with rupture indicate tendon
elongation.”
Statistical analysis
Given the significant heterogeneity of the published
papers, no data synthesis was performed for outcomes.
Instead, outcomes were presented as a range of outcomes
and in narrative summary fashion. Studies were sub-
grouped based on operative and nonoperative treatment.
Given the narrative fashion of reporting outcomes, no
assessment of certainty of evidence was conducted.
Results
e initial search identified 750 studies, with 452 stud-
ies remaining after duplicate removal (Fig.1). After title
and abstract review, 37 studies remained and were evalu-
ated in full-text with a total of five studies included in this
review [13, 24, 31–33]. ere was substantial agreement
between reviewers for title and abstract review (κ = 0.750;
95% CI, 0.625 – 0.876), and almost perfect agreement
for full-text (κ = 0.874; 95% CI, 0.632 – 1.000). ere
was one retrospective cohort study [13] and one retro-
spective case series [24] (which were both level IV evi-
dence), as well as three case reports [31–33] (which were
level V evidence). All studies had good methodologic
quality based on MINORS scoring. e comparative
study [13] had a score of 18 and the average of noncom-
parative studies was 10.5 (SDC 2). Two studies assessed
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Lameireetal. BMC Musculoskeletal Disorders (2025) 26:71
non-operative management of Achilles tears, with one
comparative study and one case series [13, 24]. e com-
parative study assessed the outcome of nonoperative
treatment of myotendinous and midsubstance Achilles
tendon ruptures/tears [13]. e three case reports [31–
33] all described patients undergoing operative manage-
ment of myotendinous Achilles tendon ruptures via open
surgical repairs.
Patient demographics
ere were a total of 70 patients included in this review.
Sixty-seven patients underwent non-operative manage-
ment (30 patients in one study [24] and 37 in another
[13]), with an average age ranging from 40.8 to 51.0years
(Table1). ree patients underwent operative manage-
ment with ages of 16, 36, and 39. e female proportion
of patients undergoing nonoperative management ranged
from 10.8 to 30.0%, and there were two men and one
female that underwent operative management. Follow-
up average duration ranged from 12.0 to 40.5 months
for nonoperative patients and the follow up was 6, 8,
and 12-months for operative patients. Body Mass Index
(BMI) was reported for two operative patients and was
34.0 and 37.6. ree studies [24, 31, 33] used MRI to
diagnose the location of the Achilles tear, one study [13]
used ultrasound, and one study [32] determined the loca-
tion intra-operatively.
Sports/athletic participation was the most common
activity reported during injury (Table 1). One publica-
tion [33] reported that the patient was using a selective
androgen receptor modulator (SARM) prior to Achilles
rupture, and this same patient tore their opposite Achil-
les tendon on postoperative day four when using it as
their weightbearing leg. is second tear was located just
distal to the myotendinous junction.
Rehabilitation protocol
Full rehabilitation protocols for each study can be found
in Table2. Four studies [24, 31–33], including all opera-
tive patients, had a period of initial non-weightbearing
Fig. 1 PRISMA diagram
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Lameireetal. BMC Musculoskeletal Disorders (2025) 26:71
Table 1 Patient demographics
BMI Body mass index, NR Not reported, SD Standard deviation
Sex, n Side Age Follow-up
Author (Year) Patients, n Male Female Left Right Mean SD (range) Mean, mo Range BMI Injury Activity
Nonoperative
Ahmad (2013) [24] 30 21 9 15 15 40.8 NR (24–54) 40.5 23–81 Basketball 33%, Running 10%, Soccer 10%, Cross‑training 6.7%,
Baseball 3.3%, Martial arts 3.3%, Weightlifting 3.3%, Non‑Athletic
20%
Carmont (2024) [13] 37 33 4 19 18 51 12.5 (NR) 12 Football 20%, Running 20%, Pushing vehicles 20%, Badminton 10%
Operative
Gould (2021) [33] 1 1 1 36 6 34 Dodgeball
Shah (2009) [32] 1 1 1 39 8 37.6 Football
Valk (2023) [31] 1 1 1 16 12 Cheerleading
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Lameireetal. BMC Musculoskeletal Disorders (2025) 26:71
(NWB). For the non-operative patients initially immo-
bilized, they were progressed to weightbearing as toler-
ated (WBAT) at four weeks. For operative patients, they
were progressed to WBAT between five to seven weeks
postoperatively. e second nonoperative study made
their patients touch-weightbearing (TWB) initially and
appeared to progress their patients to WBAT by 6weeks
(although their reported protocol does not specifically
state this).
Operative technique
All three case reports of operative repair used a pos-
terior open approach (SDC 3). All directly repaired the
tendon at the myotendinous junction using sutures. Two
studies [31, 33] used FiberWire (Arthrex) and one study
[32] used Ethibond. One study [31] had their repair aug-
mented using a bioinductive collagen patch (Regeneten,
Smith & Nephew).
Table 2 Rehabilitation protocol
NWB Non-weightbearing, TWB Touch weightbearing, WB Weightbearing, WBAT Weightbearing as tolerated
Author (Year) Rehabilitation Protocol WB Status
Nonoperative
Ahmad (2013) [24] 1. Achilles boot (Bledsoe Brace Systems, Grand Prairie, TX) with three 1‑inch wedges at the heel, non‑
weight‑bearing on their affected leg for 3 weeks
2. At 3 weeks, patients were allowed to progressively bear weight on their injured leg in their Achilles
boots. A physical therapy program for Achilles tendon strengthening was instituted after the initial 3 weeks,
with all therapy performed out of the boot full weight bearing. They were also instructed to remove a single
1‑inch wedge from the boot after every week until their ankle was plantigrade
3. At 6 weeks, patients were allowed to taper out of their Achilles boots and increase their level of activity
as tolerated
4. Between 6 and 12 weeks, patients were allowed to return to work without restrictions so long as their
pain and function had improved
Weeks 1–3: NWB
Weeks 4 + : WBAT
Carmont (2024) [13] 1. All patients were placed into an equinus functional brace made from synthetic casting material in plantar
flexion. Patients were permitted to mobilise touch weight‑bearing on the metatarsal heads as tolerated
using elbow crutches
2. After two weeks, the posterior half of the cast was removed leaving the anterior shell in situ. This
restricted dorsiflexion but permitted some active plantar flexion. At this two‑week time point, active plantar
flexion, inversion, and eversion exercises were commenced, but active dorsiflexion was avoided
3. After the six‑week time point, the functional brace was discontinued and patients were given a 1.5 cm
in‑shoe heel wedge for the next 6 weeks and referral for physiotherapy for gait retraining and a progressive
strengthening exercise programme
Weeks 1–6: TWB
Weeks 6 + : WBAT
Operative
Gould (2021) [33] 1. Postoperatively, the patient was placed into a well‑padded short leg splint in 20° of plantarflexion. They
were instructed to remain non‑weightbearing on his right lower extremity for 4 weeks
2. He was scheduled to return to the outpatient clinic at 2 weeks postoperatively for a wound check,
with plans to transition at that time from the splint to a plantigrade controlled ankle movement (CAM)
walker boot
3. The patient completed a 3‑month course of formal physical therapy after which he resumed his own
workout regimen
Weeks 1–4: NWB
Week 5 + : WBAT
Shah (2009) [32] 1. Non‑weightbearing immediately post‑op in a gravity‑equinus well‑padded splint
2. One week after the operation, the patient was placed in a short‑leg gravity equinus cast and allowed toe‑
touch weight bearing with crutches
3. Three weeks postoperatively he was placed in an ankle‑stabilizing walking boot with a 1/4‑inch heel lift,
remaining toe‑touch weight bearing but allowing gentle range of motion exercises twice a day
4. At 6 weeks he was started on isotonic exercises with full range of motion and was allowed weight bear‑
ing as tolerated in the boot
5. At 9 weeks postoperatively the boot was discontinued, and a full physical therapy protocol was initiated
6. At 6 months he was allowed to run
7. At 8 months he made a full recovery and returned to sports
Week 1: NWB
Weeks 2–5: TWB
Week 6 + : WBAT
Valk (2023) [31] 1. Immediately postop, she was placed into a well‑padded short‑leg splint in maximum equinus to unload
the repair
2. At her 2‑week postoperative visit, she was transitioned from her splint into a non–weight bearing short‑
leg cast. She was able to be passively dorsiflexed to 20° shy of neutral
3. At 6 weeks, she was taken out of her cast and kept non–weight bearing in a controlled ankle motion
boot
4. The patient was seen at 7 weeks and physical therapy and full weight bearing were initiated
5. At 9 weeks, she was able to passively dorsiflex to 10° and was transitioned to a shoe
6. At 4 months, she regained full ankle range of motion with 20° dorsiflexion
Weeks 1–6: NWB
Week 7 + : WBAT
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Lameireetal. BMC Musculoskeletal Disorders (2025) 26:71
Objective outcomes
Objective outcomes were limited in the included stud-
ies of this review (Table3). One study [13] reported rela-
tive ATRA at 9- and 12-months post-injury and HRHI at
12-months for nonoperatively treated patients. is study
was comparative between myotendinous and mid-sub-
stance Achilles tendon ruptures. For myotendinous tears,
at 9-months they found a statistically significant decrease
(better outcome) in ATRA than for midsubstance tears
(p = 0.006), and again at 12-months (p = 0.019). At final
follow-up, there was only an average of 5.5 degrees less
resting dorsiflexion on the affected limb compared to
the contralateral. Additionally, they found a statistically
significant difference in HRHI for myotendinous tears
(p = 0.019). e heel rise index on the affected limb was
on average 79% compared to the contralateral.
Four studies [13, 24, 31, 32] (two studies that treated
nonoperatively and two studies treated operatively)
reported that all patients with myotendinous Achilles
tendon ruptures/tears were able to perform a single heel-
raise. One study [33] reported that an operatively treated
patient was able to return to powerlifting at ~ 80% prein-
jury strength (this patient had bilateral tears).
Return towork/sport
One study [24] assessing non-operative management
reported that all patients were able to return to work
at full capacity at an average of 11.8weeks (range, 8 to
22weeks) after injury. For operative studies, one patient
[32] returned to full sport (football) at eightmonths post
operation and one patient [31] returned to full competi-
tive gymnastics at 12months. e other operative patient
[33] returned to powerlifting at 80% strength.
Patient reported outcome measures
e reported PROMs were limited in the included stud-
ies (Table4). Two studies [13, 33] reported ATRS scores
at follow-up. One study assessing nonoperative manage-
ment found a mean ATRS for myotendinous junction
Achilles tendon tears was 83.6. e other study report-
ing on an operative patient that had bilateral Achilles
tendon tears (one myotendinous tear and one tear just
distal to the myotendinous junction) and reported a score
of 60 bilaterally [33]. One study [24] reported FAAM-
Sports, VAS Pain, and satisfaction rates for nonopera-
tively treated patients. e mean immediately post-injury
FAAM-Sports score was 20 which improved to 95.2
Table 3 Objective outcomes
ATRA Achilles tendon resting angle, Deg degree, HRHI heel raise height index, Mo months, SD Standard deviation
ATRA HRHI Strength
9mo Follow-up 12mo Follow-up
Author (Year) Mean, deg SD Mean, deg SD Mean, % SD
Nonoperative
Ahmad (2013) [24] No weakness, all patients able to perform 20 repetitive single‑leg heel
raises
Carmont (2024) [13] ‑6.9 4.6 ‑5.5 5 79 25 All patients were able to perform single heel rise on affected side
Operative
Gould (2021) [33] The patient had returned to powerlifting at approximately 80%
strength compared with his preinjury state
Shah (2009) [32] Able to easily perform single heel‑raise at 4 months
Valk (2023) [31] Able to perform single heel‑raise at 5 months
Table 4 Patient reported outcome measures
ATRS Achilles tendon total rupture score, FAAM Foot and Ankle Ability Measure, VAS Visual analog scale
ATRS FAAM-Sports VAS Pain Satisfaction
Follow-up Initial Follow-up Initial Follow-up Excellent Good Fair
Author (Year) Mean SD Mean Range Mean Range Mean Range Mean Range % % %
Nonoperative
Ahmad (2013) [24] 20.2 (31–89.3) 95.2* (66.7–100) 8.2 (2–10) 1.3* (0–5) 76.7 20 3.3
Carmont (2024) [13] 83.6 3.5
Operative
Gould (2021) [33] 60
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Lameireetal. BMC Musculoskeletal Disorders (2025) 26:71
(p < 0.05) at final follow-up. VAS pain improved from
8.2 post-injury to 1.3 (p < 0.01) at final follow-up. ey
also reported that 76.7% of patients rated their outcome
as excellent, 20% reported it as good, and 3.3% reported
their outcome was fair.
Complications
ere was one reported possible superficial infection in
the operative case reports [31], and they were started on
cephalexin as prophylaxis and did not have any issues. No
re-ruptures were reported for either operative or nonop-
erative management of myotendinous Achilles tendon
tears. In the comparative study [13] between nonop-
eratively treated myotendinous and midsubstance tears,
they reported no re-ruptures in the myotendinous group,
but two patients (8.3%) in the midsubstance group re-
ruptured. Otherwise, for the myotendinous tearsgroup,
they reported one deep-vein thrombosis and one case of
adhesions.
Discussion
To our knowledge, this is the first systematic review to
assess the management of myotendinous junction Achil-
les tendon ruptures. is study was undertaken given the
clinical concern, in our experience, of increasing patients
unsatisfied with nonoperative management of their myo-
tendinous Achilles tendon tears that have healed elon-
gated; decreasing their push off strength, altering their
gait, and impacting their satisfaction. e majority of
studies in this review assessed patients with myotendi-
nous Achilles tendon ruptures undergoing nonoperative
rehabilitation, with only three case reports on operative
management. Regardless of treatment type, all patients
were reported to have good strength as evident by their
ability to perform a single-heel raise, and were able to
return to sport or work. Patients also reported improved
subjective outcomes including reduced pain, improved
ability to perform sport activities, and high rates of
satisfaction.
Nonoperative management of Achilles tendon ruptures
may be influenced by the location of the tendon rupture.
Functional rehabilitation has been shown to be an effec-
tive treatment option for midsubstance Achilles tears
[17], however, there has been limited research on the best
rehabilitation protocol for nonoperative management of
myotendinous tears. In this review, one study [24] treated
patients with classical immobilization and another study
[13] treated patients with more modern functional reha-
bilitation. In the study by Carmont etal. [13], the authors
compared nonoperative management of myotendinous
Achilles tendon ruptures to that of midsubstance Achil-
les tendon ruptures using functional rehabilitation. ey
found that with their rehabilitation protocol (shown in
Table 2), patients with myotendinous Achilles tendon
ruptures had no objective tendon elongation (defini-
tion in the Methods section) at final follow-up. In com-
parison, they found that five patients with midsubstance
Achilles tendon ruptures unfortunately experienced
tendon elongation. Tendon elongation can significantly
impact a patient’s plantarflexion power and overall satis-
faction [34, 35]. All patients in the myotendinous group
were able to do a single-leg heel raise and had on aver-
age 79% the heel-raise ability (HRHI) compared to their
contralateral side. In comparison, two patients with
midsubstance tears were unable to do a single heel-raise
(although they could not do one on their uninjured side
either) and their HRHI was 59%. Based on the findings
reported by Carmont etal.[13], myotendinous junction
Achilles tendon ruptures may be more amenable to non-
operative functional rehabilitation with less risk of ten-
don elongation and weakness compared to midsubstance
Achilles tendon ruptures.
Additionally, Ahmad etal. [24] found full healing of the
Achilles MTJ in all 30 patients studied and concluded
that “nonsurgical treatment of myotendinous Achilles
ruptures results in a high rate of myotendinous healing
and improved patient function” [24]. is may be due to
the innate regenerative capabilities of the myotendinous
junction, along with increased healing due to improved
blood flow compared to the tendon proper [11, 36]. A
recent in-vivo mice study by Yamamoto etal. [37] exam-
ined the regeneration process of the MTJ after injecting
collagenase (simulating damage/tearing of the MTJ) [37].
ey found that MTJ regeneration occurs along with
regeneration of the muscle. ey also found that after
application of collagenase, the MTJ significantly short-
ened, however over time, it recovered in length [37]. is
study further demonstrated that MTJ injuries have the
potential of regenerating and remodeling, which may be
why outcomes of nonoperative management of MTJ have
good rates of healing and patient function.
e majority of patients in this review sustained their
myotendinous Achilles tendon ruptures during sport.
e Achilles tendon is comprised of the soleus and the
medial and lateral heads of the gastrocnemius [24]. e
soleus originates from the posterior aspect of the tibia
and only crosses the ankle, whereas the gastrocnemius
originates from the posterior aspect of the femur and
crosses both the knee and the ankle [32, 38]. When the
Achilles tendon is stretched, there may be differential
stresses applied to the gastrocnemius and soleus depend-
ing on the position of the foot and knee, and may pre-
dispose the Achilles tendon to tear at the myotendinous
junction versus midsubstance [32]. Interestingly, the
comparative study between midsubstance and myo-
tendinous tears [13], found that 29% of patients with
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Page 9 of 11
Lameireetal. BMC Musculoskeletal Disorders (2025) 26:71
midsubstance tears sustained their injury when only
walking with none reported for myotendinous tears. is
is a relatively low energy mechanism injury compared
to the more active sports reported in their patients with
myotendinous tears. is may be due to the differential
load stressed on the posterior calf muscles during certain
exercises that my pre-dispose patients to tear the myo-
tendinous or the midsubstance portion. Although there
are no studies published on this, it is possible that when
myotendinous junction tears occur, they occur more
preferentially in sports/activities with a more predomi-
nant athletic stance (knees bent) than when patients are
at lower demand and knees are straighter (walking).
In terms of surgical management of myotendinous
Achilles tendon ruptures, many different options have
been described. Giordano et al. [10] performed a ret-
rospective review of all patients at their institution that
underwent operative management of an Achilles tendon
rupture. is study was excluded from our review as
there were no clinical outcomes reported for the patients.
For myotendinous junction ruptures, they found that
57.1% (eight patients) had standard end-to-end repairs
of the tendon and that 42.9% (six patients) had an aug-
mented repair (defined as “using an isolated flexor
hallucis longus (FHL) transfer, FHL transfer plus end-
to-end repair, or allograft”). In our systematic review, we
included three case reports of patients that underwent
operative management of their myotendinous junc-
tion Achilles tendon ruptures. All patients underwent
direct end-to-end tendon repairs, with one patient hav-
ing an additional adjunct. e patient with an adjunct
was a 16-year-old female who was an elite gymnast [31].
e authors discussed the patient’s case with “local and
national experts in the Subspecialties of Sport and Foot
& Ankle” and considered the use of a Regeneten (Smith
& Nephew), a bioinductive collage patch, to augment the
repair. Intraoperatively, they reduced the tendon with
“excellent” approximation but decided to augment with
the bioinductive collagen patch due to elite level of the
athlete and the myotendinous location of the rupture.
Postoperatively, she was able to return to full sport and
competition but did have a superficial wound concern
and was given cephalexin prophylactically. MRI obtained
between 6- to 7-months after surgery showed tendon
healing with increased thickness. e authors concluded
that for high level athletes and/or tears of the myotendi-
nous junction, bioinductive collagen patches may have a
role in augmentation.
Locating the site of Achilles tendon rupture is impor-
tant, as there may be different outcomes based on
common rupture sites (as measured in relation to the cal-
caneal insertion). Studies by Bäcker etal. [39] and Park
etal. [40] found that the average distance from rupture
to calcaneal insertion was 5.86 ± 2.66cm and 6.4 ± 1.5cm,
respectively. is was somewhat contradictory to previ-
ous reports indicating that common tears occurred closer
to the calcaneal insertion, from 2–6cm [9]. Cao etal. [9]
compared the surgical outcomes of 117 patients that had
surgical management of Achilles tendon ruptures based
on location of tear [9]. ey found the average rupture
site was 4.5 ± 1.3cm from the calcaneal insertion. e
authors also found that those with more distal Achilles
tendon tears (< 4.5cm) had more satisfactory postopera-
tive outcomes (77% of patients had an ATRS > 80), than
those with more proximal tears (≥ 4.5cm; 56% of patients
had an ATRS > 80) [9]. is study was excluded from
the present review as they did not specifically report
and compare MTJ tears, although those that were more
proximal may have in fact been, or were very close to,
the MTJ. is may indicate that more proximal tears in
the MTJ may have worse surgical outcomes compared to
mid-substance tears.
e exact location of Achilles tear, gap distance, and
quality of surrounding/remaining tendon/fascia can
have significant clinical implications. Cao etal. [9] used
ultrasound to determine the exact location of the tear, as
the clinical examination can be excellent in determining
if there is disruption of the Achilles tendon but can be
unreliable in the location and gap distance [33]. A sur-
vey of Orthopaedic surgeons found that there was con-
fusion regarding the exact location of the myotendinous
junction. e majority of surgeons estimated the level of
the myotendinous junction to be higher than it was [11].
erefore, surgeons may offer surgery on tears of at MTJ,
although they believe they will be operating on a midsub-
stance tear based on clinical examination solely. If more
proximal tears and tears of the MTJ fair worse surgically
than those treated nonoperatively [9], it is important to
know exactly where the tear is and its relation to the MTJ,
to better counsel patients on the expectations of opera-
tive vs nonoperative management. MRI is effective for
assessing the Achilles tear location; however it is expen-
sive and can be less available to patients relative to other
imaging modalities [41]. Ultrasound on the other hand, is
readily available and relatively inexpensive. ere may be
concern that ultrasound would be inadequate but recent
studies have shown that ultrasound, with a well-trained
ultrasound technologist, can be just as reliable as MRI for
determining tear location and gap size [41]. erefore,
given the availability of ultrasound, this may be a great
modality to examine all Achilles tendon tears to better
counsel patients on expected operative outcomes.
Limitations
e main limitation of this study is the limited number
of studies assessing the outcomes of nonoperative and
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Page 10 of 11
Lameireetal. BMC Musculoskeletal Disorders (2025) 26:71
operative treatment of myotendinous Achilles tendon
ruptures. Nevertheless, this review is an up-to-date and
comprehensive review of all the literature, which creates
a foundation for clinical treatment and further research.
Another limitation was the level of evidence of the
included studies was low, with all studies being level IV
or lower. With operative management, there were only
three case reports (level V evidence), which may reflec-
tive the rarity of operative management of this injury.
Lastly, one study [13] included both partial and full myo-
tendinous Achilles tendon ruptures (excluded isolated
tears of the medial gastrocnemius), which can alter the
strength outcomes, as partial tears may have less risk of
tendon elongation.
Conclusion
Both nonoperative and operative management of myo-
tendinous Achilles tendon ruptures demonstrated good
outcomes after injury, although there is a limited amount
of literature on this topic. Given that nonoperative
treatment appears to yield good strength and return to
activity, it may be preferred in the majority of patients.
Operative management may be indicated in high level
athletes. Imaging to determine the exact location of
injury, quality of tendon, and gap distance may further
aid when considering treatment options. Higher level
evidence studies are required to determine the optimal
treatment of myotendinous Achilles tendon ruptures.
Abbreviations
AAOS American Academy of Orthopaedic Surgeons
ATRA Achilles Tendon Resting Angle
ATRS Achilles Tendon Total Rupture Score
BMI Body Mass Index
CAM Controlled Ankle Movement
FAAM Foot and Ankle Ability Measure
HRHI Heel‑Rise Height Index
LOE Level of Evidence
MINORS Methodological Index for Non‑randomized Studies
MRI Magnetic resonance imaging
MTJ Myotendinous junction
NWB Non‑weightbearing
PROMs Patient Reported Outcome Measures
PRISMA Preferred Reporting Items for Systematic Reviews and
Meta‑Analysis
SARM Selective Androgen Receptor Modulator
SDC Supplementary Digital Content
TWB Touch‑weightbearing
WB Weightbearing
WBAT Weightbearing as Tolerated
VAS Visual Analog Scale
Supplementary Information
The online version contains supplementary material available at https:// doi.
org/ 10. 1186/ s12891‑ 025‑ 08286‑8.
Supplementary Material 1.
Acknowledgements
Not applicable.
Authors’ contributions
D.L.L. was a major contributor to the overall creation and execution of the
study and lead data extraction and drafting of the manuscript. L.R. was a sig‑
nificant contributor that helped review articles, extract data, and draft of the
manuscript. M.H. was a major contributor that reviewed and redrafted of the
manuscript. D.W. was a major contributor to the conceptualization of the pro‑
ject and was significantly involved in editing and redrafting the manuscript.
S.S.P. was involved in the conceptualization and was a major contributor in
writing the manuscript. All authors read and approved the final manuscript.
Funding
No funding was obtained for the creation of this manuscript.
Data availability
All data and materials are available publicly based on previous publications.
Declarations
Ethics approval and consent to participate
Not applicable, publicly available information.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Author details
1 Division of Orthopaedic Surgery, Department of Surgery, University
of Toronto, Toronto, ON, Canada. 2 Queen’s School of Medicine, Queen’s Uni‑
versity, Kingston, ON, Canada. 3 Division of Or thopaedic Surgery, St. Michael’s
Hospital, Toronto, ON, Canada. 4 Division of Orthopaedic Surgery, Women’s
College Hospital, Toronto, ON, Canada. 5 Division of Orthopaedic Surgery, Sun‑
nybrook Health Sciences Centre, Toronto, ON, Canada. 6 University of Toronto
Orthopaedic Sports Medicine Program (UTOSM), Toronto, ON, Canada.
Received: 14 September 2024 Accepted: 3 January 2025
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