University of Groningen
Achilles tendon rupture
Dams, Olivier Christian
DOI:
10.33612/diss.171082409
IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from
it. Please check the document version below.
Document Version
Publisher's PDF, also known as Version of record
Publication date:
2021
Link to publication in University of Groningen/UMCG research database
Citation for published version (APA):
Dams, O. C. (2021). Achilles tendon rupture: current clinical practice, imaging and outcome. University of
Groningen. https://doi.org/10.33612/diss.171082409
Copyright
Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons).
Take-down policy
If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum.
Chapter 3
Imaging modalities in the diagnosis and monitoring of Achilles
tendon ruptures: a systematic review
Olivier C. Dams, Inge H.F. Reininga, Jan L. Gielen, Inge van den Akker-Scheek,
Johannes Zwerver
ABSTRACT
Objective: To determine the role of imaging in the diagnosis and monitoring of the
Achilles tendon rupture (ATR).
Study design: Systematic review
Data sources: PubMed and EMBASE in November 2016
Eligibility criteria: Clinical studies providing information on the methods and role of
imaging in the diagnosis and monitoring of the ATR were included.
Results: Fifty-six studies were included, most concerning the use of ultrasound (n = 37)
or MRI (n = 18). Seven studies provided data on the diagnostic accuracy of imaging.
Most ultrasound studies used a 7.5 MHz probe (19/32 studies) and scanned the patient
bilaterally in prone position, with recent studies tending to use higher frequency probes
(r = 0.42). Sensitivity [for detecting a rupture] ranged from 79.6-100%; the spread in
specificity was large but two studies showed perfect (100%) data. Negative and positive
likelihood ratios ranged from 0-0.23 and 1.0-10 respectively. MRI examination was
generally performed with 1.5 Tesla (T) MRI (6/12 studies) with a strong trend for higher
T strength in more recent studies (r = 0.71). One study reported a sensitivity of 90.9%
and one a specificity of 100%. Although imaging can visualize structure and healing,
these results were generally not related to the clinical picture. Overall, ultrasound was
recommended over MRI for diagnosis and monitoring. Results of other imaging modalities
remain inconclusive.
Conclusion: The adjunct role of imaging, especially of ultrasound and MRI, in the
diagnosis and monitoring of ATRs was established. It is therefore recommended to rely
primarily on the clinical examination and evaluation and to use imaging for ruling out
other injuries and providing additional clinical information. More high-quality research is
warranted into the diagnostic accuracy of imaging as well as less conventional imaging
modalities’ diagnostic and monitoring capabilities.
INTRODUCTION
The Achilles tendon rupture (ATR) is a common sports injury that shows globally increasing
incidence figures [25, 37, 40, 47, 48, 54, 60, 62, 80], that are expected to increase further,
especially in the elderly, likely as a result of higher participation in recreational physical
activity [22, 33]. This injury significantly impairs patients with deficits persisting from 1-2
to even 10 years after injury [35, 36].
Despite the increasing incidence, long-term impairment and necessary clinical
procedures requiring significant time away from work/sport the treatment guidelines for
ATRs are inconclusive [15], leading to possible unnecessary increased healthcare costs
and an inefficient clinical protocol. Specifically the role of imaging in the diagnosis and
monitoring of ATRs is not substantiated [15].
Given that misdiagnosis of ATRs delays treatment leading to chronicity and more
(functional) morbidity [52], efficient diagnosis is essential. Currently, clinicians tend to
rely on functional tests (e.g. the Thompson test) for diagnosis; imaging (ultrasound and
MRI) is said to be reserved for the “difficult patient” [3, 51]. Additionally, conservative
(non-surgical) treatment is becoming increasingly common and clinicians now place a
greater emphasis on early weight-bearing [11, 40, 80]. Imaging could have a larger role
in predicting and preventing the most significant complications, re-ruptures and wound
infections, during the recovery phase [58]. Despite this, the role of imaging in monitoring
the increasingly emphasized rehabilitation phase is unknown [23, 82].
Hence, the aim of this systematic review study was to determine the role of imaging in
both the diagnosis and monitoring of the ATR. This review determined how imaging is
used in ATR patients, its (additional) value in the diagnosis and/or monitoring, and strived
to gain insight into the relationship between imaging and the clinical picture. Additionally,
diagnostic accuracy measures were determined for the available imaging modalities to
objectify the diagnostic role of imaging.
METHODS
This systematic review was conducted according to the Preferred Reporting Items for
Systematic reviews and Meta-Analyses protocols (PRISMA-P) [59].
Search strategy
A systematic electronic search of PubMed and EMBASE was conducted on all studies,
published between 19995 in November 2016, and providing information on the role of
imaging in diagnosing and monitoring ATRs. Implementation and validation of the search
and search methods was attained from a Medical Librarian at the University Medical
Center Groningen (see the Appendix for the complete search string). All records were
imported into Refworks (ProQuest, Bethesda, MD). Backward citation tracking was
performed on all included articles.
Inclusion criteria and procedure
Clinical studies assessing imaging techniques in either the diagnosis and/or monitoring
(of treatment) of complete ATRs were considered eligible. Studies were only included if
they provided information on the methodology of imaging examination and/or provided
imaging-specific outcomes. Only studies written in English, Dutch or German languages
were included. This review excluded studies focusing on the use of imaging during or as
a part of treatment. Case-studies, abstracts, reviews, editorials and animal-studies were
excluded.
Three reviewers were involved in the study selection process. Two reviewers (OCD and
JZ) independently selected the studies in three successive rounds. First the specified
criteria were applied to the titles, then the abstracts and finally the full texts. In case
of uncertainty a study proceeded to the next round. Disagreement was resolved by
consensus, and if agreement was not achieved, a third reviewer (IHFR) was consulted.
Data extraction and analysis
The following data were extracted from the full texts of the included studies:
Study information: year and first author(s), study design.
Methodology: patient characteristics and number, follow-up, injury and treatment applied,
imaging methods and settings.
Outcomes: recommendation for imaging in diagnosis and/or monitoring, (changes
in) tendon structure on imaging after injury and differences depending on treatment,
association of imaging with other outcomes.
Studies comparing ATR diagnostic data to a reference standard (intraoperative
confir-mation) were included in diagnostic accuracy calculations. Data required to calculate
sensitivity/specificity and positive/negative likelihood ratios (LR+/LR-) were extracted.
One author (OCD) extracted data from the included studies. Extracted data was verified
by a second author (JZ).
Methodological quality assessment
All studies were assessed for methodological quality using the Downs and Black (D&B)
checklist for randomized and non-randomized studies [20]. The original checklist contains
27 questions amounting to a maximum of 32 points. We modified the scale to a maximum
of 28 points, scoring the (final) question concerning power (sample size calculation) at
either 0 or 1 point. This is in line with previous studies [84].
The risk of bias and applicability of the articles regarding diagnostic accuracy was scored
independently by two of the authors (IHFR and OCD) using the Quality Assessment of
Diagnostic Accuracy Studies Version 2 (QUADAS-2) scoring guide [89]. Disagreement
was resolved by consensus.
Statistical methods
The sensitivity and specificity as well as the LR+ and LR- of articles presenting diagnostic
accuracy data were calculated. True negative findings were defined as surgically
confirmed partial ruptures or any other injury. LR+ greater than 10 or LR- less than 0.1
were interpreted as substantial benchmark measures for diagnostically ruling ATRs out
or in
[10].
To assess the settings and capabilities of imaging methods over time, a Spearman’s
correlation coefficient was calculated between both the frequency (MHz) of ultrasound
machines and/or MR strength (Tesla) of MRI, and the difference (in years) between
the year of the study and 1995. Correlation coefficients were interpreted according to
Domholdt [19]. Data were analyzed using the IBM SPSS Statistics for Windows software
(Version 23.0, Armonk, NY: IBM Corp.).
RESULTS
Search results
The applied search string yielded 1781 articles (Figure 1). Of these articles 54 met our
inclusion criteria and 2 were included after backward citation tracking, yielding a total of
56 included studies. Tables 1, 2, 3 and 4 show the extracted data and methodological
quality of the included studies. Thirty-seven studies concerned ultrasound [1, 2, 5–8,
12–14, 17, 21, 27–30, 32, 34, 38, 39, 41–43, 45, 55–57, 61, 63, 65, 68, 71, 72, 81,
83, 85, 88, 91], eighteen MRI
[5, 16, 24, 26, 31, 44, 46, 50, 53, 61, 69, 71, 73–75, 86,
90], and nine concerned X-ray, CT, Optical Coherence Tomography (OCT), Roentgen
Stereophotogammic Analysis (RSA), Diffusion Tensor Imaging (DTI),
Fluorodeoxyglucose-Positron Emission Tomography (FDG/PET), or CT [4, 6, 21, 41, 66, 74, 76–78]. Nine studies
utilized multiple imaging modalities [5, 6, 21, 41, 43, 61, 71, 76, 77]. Seven studies [26,
29, 30, 32, 46, 56, 65]
met the criteria for diagnostic accuracy calculations and Table 4,
Figure 2 and Figure 3 show the characteristics, sensitivity and specificity and QUADAS-2
appraisal respectively.
Identification
Scr
eening
Eligibility
Included
Records identified through database searching
(n = 1781)
Records after duplicates removed (n = 1488)
Records screened (n = 339)
Full-text articles assessed for eligibility
(n = 78)
Records excluded (n = 261)
Studies included in qualitative synthesis
(n = 56)
Full-text articles excluded, (n = 24) with reason: language (n=1), insufficient or absent description of imaging methodology/outcome (n=6), study design (abstract, case study,
review, editorial) (n=6), not related to (clinical) monitoring and/or diagnosis (n=2), other injury (n=8),
animal study (n=1).
Figure 1. Search string and data selection results
Additional records identified through backwards citation tracking
67
Tab le 1. S tud ies co ncer ni ng d iag no st ic and m oni to ring d at a: ul tr aso und St ud ies D esi gn N Pat hol ogy + An aly sis Im ag in g Fol low -u p Im ag in g C har act er ist ics O ut com es and C oncl usi ons D& B Sc or e Agr es et al. [1 ] Pr os pect iv e cohor t 20 Ac hille s tendon r upt ur e su rg ical ly treat ed. U ltr as ound, dyn am om et ry and gai t anal ysi s U ltr as ound 2-6 y ear s af ter sur gi cal repai r B-m ode ul tras onogr aphy w ith a 7 .5 M H z pr ob e. P revi ou sl y inj ur ed and cont ral at er al li m bs w er e i m ag ed . Inj ur ed tend ons w er e sti ffe r a nd ha d gr eat er res t l engt h. Tendon s tiff ne ss cor rel at ed w ith al ter ed m axi m um pl an tar flexi on m om ent d ur ing g ai t ( r = −0. 509) . 14 Am lang et al . [2 ] C ro ss -sect io nal 273 A ch ille s tendon rupt ur e. 226 "f re sh " rupt ur es , 47 "out da te d" . U ltr as ound us ed t o det er m in e ty pe of rupt ur e U ltr as ound Si ngl e s can 7. 5 M H z, pr one pos iti on, 20 ° pl an tar flexi on , dyn am ic exam inat ion f or pr oof of inj ur y. U ltr as ound r el iabl e fo r d iff er en tia tio n in to rupt ur e t ype ( par tial or com pl et e) . U sef ul fo r t re at m en t sel ect io n. 18 Bl ankst ei n et al . [6 ] Pr os pect iv e cohor t 20 C om pl et e rupt ur e, su rg ical ly treat ed pa tie nts U ltr as ound U ltr as ound fo r di ag no si s (n =2 0), int raoper at iv e eval uat ion (n =5) , and im m edi at e po st op er at ive (n =15) and fo llo w -up at 6 m ont hs 5-13 M H z, bi lat er al exam inat ion. Int ra and po st op er at ive ul tras ound com par is on ben efici al . U ltr aso un d can gui de t reat m ent . Tendon t hi ck er at 6 m ont hs. 16 Bl eakney et al . [8 ] Pr os pect iv e cohor t 70 Ac hille s tendon U ltr as ound Av er age of 63 m ont hs Bila te ra l exam inat ion, 7. 5 U ltr as ound l itt le cor rel at ion w ith 2168
rupt ur e, su rg ical ly an d con ser vat ivel y treat ed pa tie nts M H z, p at ient p rone fe et o ve r t abl e, longi tudi nal and trans ver se pl anes . pa thol ogy a nd fu nc tio n/ pa in . U ltr as ound s how s long t er m di ffer ences in s truct ur e, pos si bl y repr es ent ing tendi nopat hi c ba ck gr ound. N o di ffe re nc e i n t endon st ruc tur e de pe ndi ng on t reat m ent . Reco m m end at io n: dyn am ic, m or e t ha n one pl ane ul tras ound. Busi lacchi et al . [ 12] Pr os pect iv e cohor t 25 Spont aneous rupt ur e, su rg ical ly treat ed, 60 cont rol tendons scan ned to det er m in e nor m al el ast ogr ap hi c range U ltr as ound + sonoe la st ogt ra phy 40 day s, 6 m ont hs and 1 y ear U ltr as ound w ith B -m od e f unct io n ( 5-12 M H z) . P at ient pr one , bot h a nk le s ov er bed. B ilat er al exam inat ion. El ast ogr am supe rim pos ed af ter ul trasound . Thi ck nes s i ncr eas ed in bot h t endons . Sti ffnes s i ncr eas ed i n bot h t endons , cont ral at er al tend on incr eas ed i n s tiff ne ss ov er ti m e. Inv er se cor rel at ion b et w een su bj ect ive o ut co m e and st iff ness ( r = -0. 42) . 24 C hen et al . [13] Pr os pect iv e cohor t 14 14 A chi lles tendon rupt ur es , 36 cont rol s U ltr as ound + sh ear w ave el ast ogr ap hy 2 r upt ur es in “he al ing st ag e” , 1 2 rupt ur es w ithi n 24 h Real -tim e su per so ni c sh ear w ave el ast og rap hy coup led w ith a linear ar ray trans ducer (4 –15 M H z) used to assess t he el ast ici ty of the Achi lles tendons . Each t end on w as scan ned in a pr one The anat om ic stru ctu re o f th e rupt ur ed t endons w as easy t o di st ingui sh on t he el ast ici ty m ap . The el ast ici ty val ues of the nor m al tendons w er e si gn ifican tly hi gher than t he rupt ur ed ones . 1469
pos iti on w ith t he fo ot h an gi ng ov er the edge of the ex am inat ion be d i n a ne ut ra l pos iti on. El ast ogr ap hy pr ovi des m or e fu nc tio na l i nf or m at ion fo llo w in g he al in g; hel ps to opt im ize treat m ent fol low ing fu nc tio na l rehabi lit at ion. C hille m i e t al. [14] Pr os pect iv e cohor t 38 Po st -su rg er y rupt ur es . 35 com pl et e, 3 pa rtia l. 3 7 pat ien ts com pl et ed one year fo llo w -up U ltr as ound 5, 24, 48 w eeks Pr one, feet ov er tabl e, ank les neut ral , 7. 5 M H z pr obe , i nj ur ed a nd uni nj ur ed t endon, longi tudi nal and trans ver se pl anes . U ltr as ound confi rm ed di ag no si s af ter Thom ps on t es t i n so m e p at ien ts. U ltr as ound v al uab le as diagnos tic /pr ognos tic im agi ng. U ltr as ound sh ow s ab no rm al iti es and heal ing up to 48 w eeks p ost -su rg er y. 17 C ou tts e t al. [17] Pr os pect iv e cohor t 25 Ac hille s tendon rupt ur e, 21 ul tras ound scan s, su rg ical ly treat ed pa tie nts U ltr as ound M ean: 3. 4 year s ( ran ge: 6 m ont hs - 9. 25 years 7. 5 M H z pat ient pr on e, feet hangi ng ov er tabl e, neut ral , longi tudi nal and trans ver se pl anes . Bila te ra l exam inat ion. Inj ur ed tend ons w er e thi ck er . U ltr as ound ab nor m al iti es p ost -sur ge ry not associ at ed w ith cl ini cal p ict ur e. 16 G en ovese et al . [ 27] Pr os pect iv e cohor t 14 14 w ith hi st or y of A chi lles tendon rupt ur es su rg ical ly treat ed, 10 cont rol s U ltr as ound, Dop pl er and cont rast -enhanced ultras ound Si ngl e s can w ithi n 2 year s p ost -ru ptu re Pat ient pr one, ankl e at 90 deg rees, 1 3-14 M H z longi tudi nal . Reco m m end at io n: no Dop pl er im m ed iat el y afte r act ivi ty ( m or e bl ood flow ), Doppl er si gn al n ot in di cat ive of di seas e, cont ras t ul tras ound m or e sen si tive t han Do pp le r fo r rev as cul ar izat ion. 1570
G er em ia et al . [28] Pr os pect iv e cohor t 18 18 w ith pr evi ou s Ac hille s tendon r upt ur e (co m par iso n ear ly m ob ilized and im m ob iliz ed ), 9 heal thy cont rol s U ltr as ound Si ngl e s can 2 y ear s af ter in ju ry Li near pr obe, 7. 5 M H z, ul trasound pr ob e w as p laced pe rpe ndi cul ar to the t endon and thr ee t rans ver se im ages w er e obt ai ned at 2 cm , 4 cm , and 6 cm fro m th e te ndo n' s ins er tion on t he cal caneus. Tw o y ear s pos t-su rg ical rep ai r, t he rupt ur ed A chi lles tendon m echani cal and st ruct ur al pr op er tie s (C SA , lengt h, for ce s tres s-st ra in ) d iff er f ro m uni nj ur ed. Inj ur ed tendon i s m or e com pl iant . P at ient s’ uni nj ur ed t endons w er e si m ilar to cont rol s. 19 H ol lenber g et al . [ 34] Pr os pect iv e cohor t 11 Ac hille s tendon rupt ur e, conser vat ive treat m ent U ltr as ound + Dop pl er Ini tial scan w ithi n 48 hour s. Fol low -up at m ean 22. 4 m ont hs (rang e: 7 -38 m ont hs) Inj ur ed and cont ral at er al tendon, 7. 5 M H z, pa tie nt pr one , dyn am ic exam inat ion. U ltr as ound to con fir m di agnos is . The A TR tr eat ed non -su rg ic ally has a di ffe re nt s onogr aphi c ap pear ance t han heal thy or acut el y rupt ur ed t endon. 10 H uf ner et al. [38] Pr os pect iv e cohor t 168 A ch ille s tendon rupt ur e. U ltr as ound + fo llo w -up 125 (p at ient s f or fo llo w -u p). C ons er vat iv el y treat ed pa tie nts U ltr as ound Ini tial scan fo r t re at m en t sel ect io n. Fol low -up at 4, 8, and 12 w eeks 7. 5 M H z, pat ient pr one , pl an tar flexi on . U ltr as ound can sel ect p at ien ts f or non -su rg ical treat m ent by m easur ing g ap . Inj ur ed tend on thi ck er . Li ttle cor rel at ion b et w een ul tras ound and fu nc tio na l o ut co m e. 10 H ut chi son et al . [ 39] Pr os pect iv e cohor t 273 S peci al ized pr ot oc ol for Ac hille s tendon r upt ur e U ltr as ound 4, 6, and 9 m ont hs Fl ex and ex tend the k nee dur ing exam inat ion, and assess t he am ount U ltr as ound us ed f or di agnos is to det er m in e si te an d ext ent of rup tur e and 1771
pa tie nt s. 211 m anag ed conser vat ivel y, 63 s ur gi cal ly . Pat ient s scan ned w ith in 2 w eeks of inj ur y of oppos iti on of tendon ends in var yi ng d eg rees o f eq ui nus. D ynam ic pl an tar flexi on o f fo ot . gap s ize. R out ine ul tra sound pr ov es cost -e ffect ive ( less unneces sar y s ur gi cal int er vent ions ). Kai nb er ger et al . [ 42] Ret ro sp ect ive cr oss -sect io nal 52 Tendoni tis , heel -s w ellin g or s us pect ed rupt ur es . 8 rupt ur es . U ltr as ound findi ngs us ed to cor rel at e w ith fi na l di agnos is U ltr as ound 5-10 M H z, trans ver se and sag itt al p lan es, dyn am ic exam inat ion. U ltr as ound s igns not sp eci fic fo r each o f the di agnos es . Dis cr epancy bet w een sym pt om s an d ul tras ound s igns . U ltr as ound f or di agnos is a nd t o defin e ext en t o f di sease. 22 Ko tn is e t al. [45] C ro ss -sect io nal 125 A ch ille s tendon rupt ur e, bot h su rg ical an d conser vat ive pa tie nts U ltr as ound U ltr as ound w ithi n 7 da ys of inj ur y Foot in r es ting pos iti on t he n m ov ed t o pl an tar flexi on , com par ison m ad e bet w een g ap . U ltr as ound us ed f or treat m ent s el ect ion based o n g ap si ze can r ed uce r e rupt ur e. 21 M aj ew ski et al . [ 55] Pr os pect iv e cohor t 73 Ac hille s tendon rupt ur es , bot h su rg ical ly an d conser vat ivel y treat ed pa tie nts U ltr as ound 4, 8, 12 and 26 w eeks and 2.5 y ear s 7. 5M H z neut ral , pa tie nt on st om ach . N o cor rel at ion bet w een echo st ruc tur e a nd t endon fu nc tio na lit y. U ltr as ound cannot st udy qua lit y of heal ing and r el at ion to f unct ion, onl y st ag e. N o d iff er en ce bet w een h eal in g st ru ct ur e i n su rg ical and conser vat ive pat ien ts. 1572
M er k et al . [57] Pr os pect iv e cohor t 54 Ac hille s tendon rupt ur e, su rg ical ly treat ed pa tie nts U ltr as ound Av er age 4. 4 y ear s 7. 5 M H z f oot ov er exam tab le com par e t o heal thy cont ral at er al tendon , longi tudi nal and trans ver se pl anes . N o cor rel at ion be tw ee n U ltr as ound ab nor m al iti es and cl ini cal resul ts. 13 O fer et al . [63] Pr os pect iv e cohor t 9 8 degener at iv e and 1 traum at ic rupt ur e, su rg ic ally . 9 cont rol s. U ltr as ound (m ot io n anal ysi s) Si ngl e s can, 2-9 m ont hs pos t-ru ptu re M ot ion anal ysi s ul tras ound. Dor si flexi on to pl an tar flexi on w ith linear tr ans ducer . Bila te ra l exam inat ion. N egat iv e as ym m et ry hi gher in dor si flex ion ph ase o f de ge ne ra tiv e but not in t raum at ic r up tur e pos t-oper at iv el y. U ltr as ound t o gui de deg en er at ive ch an ge of cont ral at er al tendon. 13 Q ur esh i et al. [68] Pr os pect iv e cohor t 26 C onfi rm ed Ac hille s te ndon r upt ur e by c lin ic al pi ct ur e a nd ul tras ound U ltr as ound Si ngl e s can w ith in a w eek of inj ur y Pr one, 12 M H z linear tr ans ducer , axi al /sagi ttal pl ane s. The ga p di st an ce w as seq uen tial ly m easur ed w ith t he fo ot in m ax im um ankl e eq ui nus and the k nee i n 0° , 30° , 60° , and 90° of flexi on . U ltr as ound us ed t o confir m d iagnosi s.Tendon edge apposi
tion f ol low ing acut e A chi lles t end on rupt ur e i s dependent on bot h knee flex ion and foot p osi tion. U ltr as ound can ident ify pat ient s w ho ben efit m ost fr om su rg ery /a t ri sk o f re -rupt ur e. 20 Rup p et al . [72] Pr os pect iv e cohor t 60 Po st -s urg ery Ac hille s tendon r upt ur e U ltr as ound Si ngl e s can at a m ean of 11 y ear s (rang e 2 -19) In jur ed and cont ral at er al tendon, 7. 5 M H z, pa tie nt pr one a nd fe et 1 0 de gr ee s do rsi ext en si on . N o cor rel at ion be tw ee n ul tra sound and cl ini cal out com e, al though ul trasound doe s s how long -las ting al ter at ions . 10
73
Suy dam et al. [81] Pr os pect iv e cohor t 4 4 pat ient s w ith Ac hille s tendon rupt ur e, su rg ical ly treat ed, 5 heal thy cont rol s U ltr as ound and m ot io n anal ysi s vi a EM G 6 and 12 mont hs Bila te ra l exam inat ion. Pat ient pr one, foot hangi ng o ff t he ed ge of the t ab le. B-m od e 10 M H z ul tras ound us ed t o det er m in e l en gt h. Tendon l engt h incr eas ed. M oder at e cor rel at ion b et w een EM G of lat er al gas trocnem ius and tendon l engt h ( r = 0. 52) . S light cor rel at ion w ith m ed ia l gas trocnem ius (r = 0.3 8). 12 Tan et al . [83] Pr os pect iv e cohor t 16 19 s ur gi cal ly repai red tendons com par ed to 40 asym pt om at ic tendons of 20 cont rol s U ltr as ound + sonoe la st ogr aphy M ed ian: 36. 8 m ont hs (rang e 4 -180 m ont hs) U ltr as ound exam inat ion w ith a real -tim e sonoe la st ogr aphi c scan ner at a fre qu en cy ra ng e of 5– 13 M H z The A chi lles tendons w er e exam ined axi al ly and longi tud inal ly w hi le t he p at ien t w as l yi ng in th e pr one pos iti on w ith the f oot hangi ng ov er the ed ge of the ex am inat ion tabl e i n a r el ax ed pos iti on. El ast ici ty and thi ck nes s v al ues di d not di ffer bas ed on por tion of te ndon. In al l p at ient s w ith com pl et e r up tur es, het er ogeneous and sti ff-ty pe al ter at ions w er e id en tifi ed w ith real -tim e so no el as togr aphy , thi s di ffer ed f rom cont rol s. C oncl us ion: des pi te changes m ean Am er ican O rthopedi c Foot and A nk le S cor e (A O FA S) sco re w as excel lent . 17 Vad al a et al. [85] Ret ro sp ect ive co ho rt 80 Sur gi cal ly treat ed subc ut ane ous rupt ur e pa tie nts < 40 year s o ld U ltr as ound + pow er D oppl er Si ngl e s can at a m ean of 58 m ont hs (rang e 26 -116) Li near multif req uency (7 .5 -1 2 M H z). Exam inat ion of bot h t endons in longi tudi nal and trans ver se pl anes . U ltr as ound s how ed lar ger tendon. Tendon s truct ur e rem ai ned i rregul ar in m ost p at ient s. M ost pa tie nt s s how ed no neov as cul ar izat ion . 1974
Dop pl er to d isp lay neov as cul ar izat ion . W est in et al. [88] Pr os pect iv e cohor t 45 U ltr as ound of pat ien ts pa rti ci pa ting i n RC T com par ing su rg ical an d non -su rg ical tre atm en t. U ltr as ound t o m easur e di ast asi s U ltr as ound U ltr as ound pe rfor m ed w ithi n 72 hour s of in ju ry , c lin ic al and func tio na l fo llo w -u p at 12 m ont hs 13. 5 M H z m ul tif req uency linear ar ray trans ducer , us ing an 11. 4-m H z de fa ul t s et ting a nd sc anni ng par am et er s ai m ed fo r s upe rfi ci al m uscul oskel et al sc anni ng. Scanni ng of the Achi lles tendon w as p er fo rm ed in bot h l ongi tudi na l and axi al p lanes assi st ed b y dyn am ic scan ni ng du rin g p assi ve ankl e m ot ion. Pat ient s w ith a l ar ger in itia l g ap -si ze o n ul tras ound had a hi gher degr ee of re -rupt ur e. U ltr as ound us ef ul in pr edi ct ing r e-rupt ur e, and assessi ng su rg ical indi cat ion. U ltr as ound s houl d not be us ed as a di agnos tic tool due to the occur rence of fa ls e ne ga tiv es . 21 Zhang et al. [91] Pr os pect iv e cohor t 26 U ltr as ound + sh ear w ave el ast ogr ap hy of s ur gi cal ly treat ed pa tie nts U ltr as ound + sh ear w ave el ast ogr ap hy 12, 24, 48 w eeks p ost -oper at iv el y Li near ar ray trans ducer (4 –15 M H z) w as us ed t o as ses s t he el ast ici ty of the Ac hille s tendons . E ach tendon w as sc anne d i n a pr one pos iti on w ith t he fo ot h an gi ng o ve r the ed ge of the exam inat ion b ed in a neut ral pos iti on. M ean el ast ici ty val ues w er e d iff ere nt fo r r epa ire d te ndo ns. El ast ici ty val ues cor rel at ed w ith fu nc tio na l o ut co m es (o dd s r at io = 0. 92) . U S can det ect po st op er at ive sti ffn ess ( th is val ue gr adual ly incr eas ed) . 1675
Tab le 2. S tud ies co ncer ni ng d iag no st ic and m oni to ring d at a: M R I St ud ies D esi gn N Pat hol ogy + An aly sis Im ag in g Fol low -u p Im ag in g C har act er ist ics O ut com es and C oncl usi ons D& B Sc or e Fuj ik aw a et al. [24] Pr os pect iv e cohor t 39 40 acut e A chi lles tendon r upt ur es su rg ical ly repai red ( open (n =10) o r per cu tan eo us (n =30) ) M RI 4, 8, 12 w eeks 1. 5 T. S upi ne at M RI , inj ur ed t endon i n co il. Ax ial T1 and axi al /sagi ttal T1/ T2 im ages . Ear lier d isap pear ancetendon gap on T2 and i
n open s ur ger y gr oup. M RI can vi sual ize nor m al heal ing. 15 H ai m s et al. [31] Ret ro sp ect ive cr oss -sect io nal 88 W id e-ar ray of Achi lles tendon ab nor m al iti es, 94 f eet w ith "a bnor m al " M R exam inat ions w er e ret ros pect iv el y eval uat ed and clin ic ally cor rel at ed . 36% had A chi lles tendon t ear s, 13% com pl et e te ars M RI Pat ient s w ho
had been sym
pt om at ic rangi ng f rom 1 day t o 3 year s 1. 5 T M RI . T1/ T2. Pat ient s i m aged i n an ext rem ity coi l, sag itt al /axi al an al ysi s. Thi ck er tendons associ at ed w ith t ear s. T2 si gna l di d not di st ingui sh sym pt om at ic f ro m asym pt om at ic, how ev er gr eat er incr eas e i n T2 w ith pa thol ogy . H ar d t o cor rel at e M RI w ith sym pt om s. 14 Kar jal ai nen et al . [ 44] Pr os pect iv e cohor t 20 21 com pl et e su rg ical ly t reat ed rupt ur es M RI 3 and 6 w eeks and 3 and 6 m ont hs pos t-su rg er y, pr eo per at ive di agnos tic M RI of 2 pat ient s 0.1 T M RI. A t 3 w eeks p at ien t su pi ne, T1 and T2 s agi ttal , T2 in ax ial pl ane. C ont ral at er al tendo n eval uat ed as w el l. Thi ck nes s of tendon incr eas ed m os t bet w een 6 w eeks and 3 m ont hs . At 3 w eek s t endon bes t seen at T 2 sag itt al . A t 6 w eeks T 2 w ei gh ted im ages bes t. M RI poor a t pr edi ct ing A TR . M RI cor rel at es w ith fu nc tio na l c apa ci ty a t 3 20
76
(r = -0. 50 -0. 66) and 6 m ont hs ( r = -0. 50 -0. 60. M RI can assess stru ctu re . M acM ahon et al . [ 50] C ase -cont rol 21 M RI of 50 heal thy and 21 rupt ur ed pat ien ts. Det er m inat ion of tendon r ot at ion and d ist ance t o su ral n er ve M RI Dat e of rup tur e avai lab le f or 6 su bj ect s, m ean 6 day s af ter in ju ry Foot pos iti oned neut ral , w itho ut excessi ve p lant ar or do rs ifl ex io n, in a n ext rem ity coi l. Four im age acqui si tions w er e o bt ai ned , incl udi ng a s agi ttal inv er si on r ecov er y. Rup tur ed A chi lles tendons s how ed gr eat er ext er nal rot at ion at the ankl e not m or e p roxi m al to t he i ns er tion. P rox im al tendon r ot at ion cor rel at ed w ith r up tur e hei ght . The s ur al ner ve w as cl oser an ter io rly an d fa rth er la te ra lly in rupt ur es (l ik el y due t o sw ellin g/ ro ta tio n). Achi lles tendon w as thi ck er in r upt ur ed cohor t. 19 Ma ffu lli e t al . [ 53] Pr os pect iv e cohor t 16 P ost -su rg er y Achi lles tendon ru ptu re M RI Av er age 32. 5 m ont hs ( rang e 29 -36 m ont hs ) 1 T M RI of oper at ed and non -oper at ed tendon, s upi ne, feet fir st , an kl e hel d pl ant igr ade a t 90 ° fle xi on. P rot on de ns ity a nd T2 w ei gh ted im ag es. O pe ra te d t endons si gn ifican tly th icker . Pos si bl e non pa thol ogi ca l M RI ab nor m al iti es p ost -su rg er y n ot n ecessar ily of s igni ficance. 20 Reb eccat o et al . [69] Ret ro sp ect ive co ho rt 52 A chi lles tendon rupt ur e s ur gi cal ly tre ate d M RI M in im um 12 m ont hs , M RI of 40 pat ient s T1 and T2 w ei ght ed im ages , A chi lles tendons and cal f m uscl e ar e anal yzed . Ax ial and s agi ttal pl an es. M RI reveal s enl ar gem ent of oper at ed t endon. Pos si bl e r el at ions hi p bet w een m uscl e com par tm ent ar ea on M RI and sub ject ive out com e, as they decr eased si m ilar ly. 1977
Ro sso et al. [16] Ret ro sp ect ive co ho rt 52 A chi lles tendon rupt ur e, conser vat ive and su rg ical treat m ent M RI Pat ient s cont act ed af ter thr ee y ear s. M ean: 91 m ont hs 3 T M RI . I nj ur ed and cont ral at er al tend on, su pi ne, an kl e do rsi flexed at 9 0 °. T 1 in cor onal pl ane, ax ial fa t-s at ur at ed T2 a nd axi al T1. M uscl e vol um e and tendon l engt h di ffer ence in i nj ur ed and uni nj ur ed. N o di ffer ences in treat m ent gr oups . C SA cor rel at ed w ith m uscl e vo lu m e. M uscl e vo lu m e di d not c or re la te w ith Ac hille s tend on Tot al Rup tur e S co re ( AT RS ) o r tendon l engt h and onl y to a s ligh t degr ee w ith H annov er s cor e. C oncl uded t hat ul tras onogr aphy is cheap er , l ess t im e consum ing f or fol low -up. 18 Sadek et al. [73] Pr os pect iv e cohor t 18 P at ient s w ith chr oni c r up tur es and d ef ect s > 5 cm , sur gi cal ly tre ate d M RI 1 w eek pr eo per at ivel y and 4, 8, 12 w eeks p ost oper at iv el y 1. 5 T M RI . D ur ing M RI , t he p at ient lay i n the s upi ne pos iti on w ith th e a ffect ed Achi lles tendon pl ac ed on t he c oi l. The pr ot ocol s w er e sa git ta l a nd a xia l fa t-su pp ressed sp in -echo T1 -w ei ght ed im ages ax ial , and sag itt al fast sp in -echo T2 -w ei ght ed im ages . M RI used to confir m di agnos is . Achi lles tendon heal ing and t endon gap di sap pear an ce per cei ved w ith h ig her sen si tivi ty i n T 2-w ei gh ted im ag es t han T1. M RI tend on gap gr adual ly di sappear ed. 14 Sar m an et al. [75] Ret ro sp ect ive co ho rt 45 S ur gi cal ly tr eat ed pa tie nts M RI 9 m ont hs af ter su rg ery 1. 5 T M RI . The pat ien t w as p laced supi ne pos iti on a nd the l eg at res t. The M RI p rot ocol incl uded ax ial , The oper at ed s ides w er e si gn ifican tly thi ck er than the heal thy s ides at 9 m ont hs. 1478
sag itt al , co ro nal T 1-w ei ght ed t ur bo -s pi n echo, axi al p rot on den si ty -w ei ght ed, cor onal T2 -w ei ght ed tu rb o-spi n e cho, a nd cor onal shor t T1 -w ei ght ed i nv er si on recov er y s equences . W agnon e t al. [86] Pr os pect iv e cohor t 57 P ost -oper at iv e Achi lles tendon rupt ur es (n = 35 open r epai r, n = 22 per cut aneous ) M RI O pe ra tion w ithi n 2 w eeks , s ingl e pos t-oper at iv e M RI of 40 pat ien ts, aver age f ol low -up of 40 m ont hs (rang e 12 -105 m ont hs) Bi lat er al exam inat io n consi st ent w ith Reb ecat to et al . [ 69] O pe ra te d t endon thi ck er . M RI im ages di ffi cu lt to c orre la te w ith fu nc tio na l r es ul ts; s ho ul d be us ed i n di ffi cu lt cases. 17 Yas uda et al. [90] Pr os pect iv e cohor t 30 30 chr oni c ( > 4 w ee k ol d) rupt ur e pat ien ts su rg ical ly treat ed. P re and pos t-oper at iv e M RI M RI M RI pr eo per at ive and at 3 and 6 m ont hs 1. 5 T M RI , T1/ T2 w ei gh ted im ag es i n the ax ial and s agi ttal pl an es. M RI can d et ect changes pr eo per at ivel y an d po st op er at ivel y ( lar ger tendon) . Thi ck eni ng se en on T2. M RI us ed t o assess heal ing. 20 Tab le 3 . S tud ies co ncer ni ng d iag no st ic and m oni to ring d at a: o ther and co m bi ned m od al iti es St ud ies D esi gn N Pat hol ogy + An aly sis Im ag in g Fol low -u p Im ag in g C har act er ist ics O ut com es and C oncl usi ons D& B Sc or e Bag nani nchi et al . [4 ] C ase -cont rol 24 S am pl es of 14 rupt ur ed Ac hille s tendons pos t-su rg er y Pol ar izat ion Sens iti ve O pt ic al C oher ence Scanned withi n 24 h pos t-su rg ery Pri or to P SO C T scan ni ng , t he sam pl es w er e m ar ked b y i nki ng the s tar ting P SO C T scan li ne an d scan PS O C T i s abl e t o assess t he changes that oc cur w ith spont ane ous Achi lles tendon 1079
anal ysed ex -vi vo co m par ed to 10 cont rol s (p at ella r and tendi nopat hi c Ac hille s tendons ) Tom ogr aphy (PSO C T) di re ct ion f or ref er enci ng w ith hi st ol ogy . P SO C T sy st em fit ted w ith a su per lu m in escen t di od e w ith a cen tral w av el engt h of 1310 nm and a b and w id th of 52 nm . I m m edi at el y af ter be ing s ca nne d t he tendon fibr e al ignm ent , cel lul ar ity and tenocyt e nucl ei w er e ev al uat ed. rupt ur e and w ith Ac hille s tendi nopat hy . PS O C T w ill b e com pl em ent ar y t o ot her techni ques for the as ses sm ent of tendon pat hol ogy . Bi anchi et al. [5 ] Ret ro sp ect ive case -ser ies 5 Pl ant ar is tendon r upt ur e U ltr as ound + M RI U ltr as ound 8 days and M RI 10. 2 days afte r tra um a U ltr as ound: p ro ne, feet hangi ng ov er tabl e, bot h si de s, 12. 5 or 17. 5 M H z t rans du cer s. Dynam ic exam inat ion. M RI: 1 .5 T . Sagi ttal /ax ial /cor onal T2 , a xia l T 1. Bo th ul traso und and M RI d ist ingui sh Pl ant ar is tendon fro m Ac hi lle s tendon t ear . Reco m m end at io n: ul tras ound of Pl ant ar is tendon i n pa tie nt pr es ent ing w ith pa in. 14 Bl ankst ei n et al . [6 ] Ret ro sp ect ive cr oss -sect io nal 41 41 w ith A chi lles pa in, 2 A chi lles tendon r upt ur es U ltr as ound + X -ray in 1/ 3 Bi lat er al ly exam ined by us ing a 5 -13 M H z linear tr ans ducer at a const ant fr eq uency of 7. 5 M H z. R egul ar X -ray s w er e obt ai ned i n one -thi rd of the pat ient s, and the lat er al v iew of the h eel w as r evi ew ed fo r di agnos tic pur pos es . U ltr as onogr aphy shoul d be a ppl ie d in the pr im ar y cl ini c, dyn am ical ly an d i n real ti m e. C om par ed t o m ag net ic res onance i m agi ng ul tras onogr aphy has the capabi lit y of de m on stra ting phy si ol ogi ca l m ovem ent , and is 1180
si m pl er an d m or e cost e ffect ive Reco m m end at io n: ul tras ound i n pa tie nts w ith Achi lles pai n, ai ds in s ur gi cal sel ect io n. El iasson et al. [21] Pr os pect iv e cohor t 23 23 pat ient s w ith su rg ical ly repai red Achi lles tendon rupt ur e. Tant al um beads ins er ted t o m easur e el ongat ion. M easur em ent of gl ucos e upt ake, vascu lar izat io n and sub ject ive (AT RS a nd VI SA -A ) out com e FD G /P ET + pow er D oppl er ul tras onogr aphy (PDU S) 3 (n = 7 ), 6 (n = 7) , and 12 ( n = 9) m ont hs pos t-su rg ery FD G /P ET and pow er Dop pl er ul tras onogr aphy (PDU S) . Rel at ive g luco se upt ake w as hi gher at a ll t im e-poi nt s and negat ivel y cor rel at ed (r = -0. 89) w ith A TR S at 6 m ont hs af ter re pa ir. P DU S fl ow act ivi ty w as hi gher in repai red t endons than i n i nt act tendons at 3 and 6 m ont hs, b ut nor m al ized by 12 m ont hs. Ther e i s a negat iv e cor rel at ion b et w een tendon m et abol is m and P RO M ’s, m et ab ol ic act ivi ty can b e i ncr eased fo r u p to a y ea r desp ite n or m al vascu lar izat io n. 11 Jie lile et al . [41] Pr os pect iv e r andom ized t rial 57 R and om ized com par ison of ear ly p ost -oper at iv e rehabi lit at ion U ltr as ound + M ult is lic e s pir al com put er ized tom ogr aphy 8, 12, 18, 26 w eeks and 2 year s U ltr as onogr aphi c m easur em ent o f t he cr oss -sect io nal ar ea i n bot h t he he al thy s ide and the r up tur ed si de The cr oss -sect io nal ar ea of the r up tur ed si de of the te ndon w as m uch lar ger than t hat of the 2481
w ith pos t-oper at iv e cas t im m ob iliz at io n fo r n eg le ct ed Achi lles tendon ru ptu re of the t endon pe rfor m ed us ing c ol or Dop pl er w ith t he pa tie nt s l yi ng i n pr one pos iti on on t he te st ing bed an d t he an kl e i n a neut ral pos iti on. M ul tisl ice sp iral C T scan ni ng o f t he an kl e w ith th e sam e m easur em ent p ro to co l. heal thy s ide ( m or e fo r e ar ly po st -oper at iv e rehabi lit at ion) . Kar jal ai nen et al . [43] Pr os pect iv e cohor t 13 S ur gi cal ly treat ed A chi lles tendo n rupt ur es , m al e pa tie nt s. 9 w ith uni nj ur ed cont ral at er al tendon avai lab le f or bila te ra l exam inat ion M RI + ul tras ound Av er age tim e fro m su rg ery to im agi ng w as 17. 7 m ont hs (rang e 12 – 36 m ont hs ) U ltr as ound: pat ien t pl aced p ro ne, w ith feet hangi ng f ree. Li near 7. 5 M H z t rans ducer . Tr ans ver se and longi tudi nal im ages , cont ral at er al tend on im aged as w el l. M RI : 0. 1 T. T1 and T2. Bo th t end ons i m ag ed . M RI show ed m or erounded and irregul
ar cont our of inj ur ed t endon. Rup tur ed tend on w as l ar ger o n ul tras ound and de lin eat ed l es s sh ar ply . O nly M RI show ed int rat endi no us les ion. Tw o pat ient s w ith th e l arg es t int rat endi no us les ions had poor cl ini cal out com e. 16 M ol ler et al . [61] Pr os pect iv e r andom ized t rial 58 A chi lles tendon rupt ur e, su rg ical ly an d conser vat ivel y treat ed i n random ized t rial U ltr as ound + M RI U ltr as ound at 6, 12 and 24 m ont hs . M RI at 12 m ont hs U ltr as ound: 7. 5 M H z, sc anni ng of bot h tendons , l ongi tudi nal and axi al p lanes. M RI : 1 T. B ot h t end ons scan ned sep ar at el y. Supi ne, feet s light ly pla nt ar fle xe d in c oil. Ax ial and s agi ttal pl ane s, T2. Tendon w as t hi cker and m or e het er ogeneous at 1 year . N o co rrel at io n be tw ee n i m agi ng and sub ject ive or fu nc tio na l par am et er s at 1 year . N o d iff er en ce in s truct ur e ( ex cep t 22
82
fo r g lidi ng fu nc tio n) de pe ndi ng on tre atm en t. C oncl us ion: pos t-tre atm en t ul tras ound or M RI of li m ited v al ue. Par tial def ect s vis ib le in h ig he r num ber on ul tras ound. Pear ce et al . [ 66] C ase -cont rol 44 21 pos t-su rg er y Achi lles tendon rupt ur es com par ed to 23 cont rol s ( ankl e sp rai n) X-ra y Lat er al ly taken m easur em ent o f cal caneal p itch, lat er al tal ocal caneal , and tibi ocal caneal angl es . A si gni ficant di ffer en ce exi st s bet w een th e tibi ocal caneal angl e in pat ient s w ith a confir m ed rup tur e com par ed w ith a cont rol gr oup . X-ray can be us ed as an a dj unc t de vi ce . C oul d a id i n pl ast er ap pl icat io n. 15 Ro m ing er at al. [71] Pr os pect iv e cohor t 60 P ost -su rg er y. 30 al so M RI U ltr as ound +M RI 6 - 78 months U ltr as ound: 5 -7. 5 M H z dur ing flexi on /ext en si on o f fo ot . M edi al -sag itt al pl an e an d 3 cm ab ove cal caneus. B ilat er al exam inat ion. M RI: T 1/ T2 M RI, sa git ta l, b ila te ra l. Tendon r em ai ned thi ck er po st op er at ivel y. U ltr as ound and M RI had a si gni ficant po si tive co rrel at io n w ith f unc tion, ul tras ound how ev er al so cor rel at ed po sit iv ely w ith ph ysi cal d isab ilit y and red uct ion i n ph ysi cal act ivi ty. 1683
U ltr as ound pre fe rre d. Sar m an et al. [75] Ret ro sp ect ive co ho rt 16 A cut e A chi lles tendon r upt ur e po st o per at ivel y Di ffusor Tensor im agi ng ( DTI ) M RI All a t le as t 6 m ont hs pos t oper at iv el y. M ed ian fo llo w -up dur at ion w as 2 1 m ont hs (rang e 6 -80 m ont hs) 3 T s canner T1/ T2 im ages , bi lat er al exam inat ion. A xi al , sag itt al , an d co ro nal T1 -w ei ght ed. The m icr ost ruct ur e o f t he AT w as as ses sed by m uscl e fib er tr acki ng and tend on cont inui ty us ing t he f ract ional ani sot rop y ( FA ) and Appar ent D iff us ion C oe ffi ci ent (A DC ) val ues b y w ay o f D TI . DTI fr act ional ani sot rop y l ow er on inj ur ed s ide. Di ffusi on coe ffi ci ent val ues co rrel at ed sig nifi ca nt ly w ith fo llo w u p tim e (r = 0. 49 -0. 71) . D TI can be u sed as an al ter nat ive non -in va si ve techni que in t he ev al uat ion of tendon char act er ist ics dur ing t he he al ing pr ocess. 15 Schepul l et al. [78] Pr os pect iv e cohor t 10 A chi lles tendon rupt ur es su rg ical ly tre ate d RSA 6, 12, and 18 w eeks and 1 year Dur ing sur ger y, w ith a sp eci al in ject io n needl e, 2 t ant al um bead s w ith a d iam et er of 0. 8 m m w er e pl aced in t he di st al par t of the Achi lles tendon and 2 bead s w er e p laced in the pr ox im al s tub. RS A m easur es m echani cal pr ope rti es a nd com bi ned w ith C T trans ver se ar ea t he el ast ic m od ul us can be m easu red . Funct ional res ul ts at 52 w eeks cor rel at ed m od er at el y w ith m od ul us and sp eci fic st iff ness at 6-18 w eeks . R SA pos t-su rg er y can hel p ai d t reat m ent sel ect io n. 21 Schepul l et al. [77] Reanal ysi s o f d at a 65 A chi lles tendon rupt ur e, C T (+ RSA) 7. 19 and 52 w eeks O nl y a w eak cor rel at ion b et w een 1384
su rg ical ly treat ed. 61 at 7 w eeks, 5 6 at 1 9 w eeks, 5 3 at 5 2 w eeks radi odens ity and fu nc tio na l r es ul ts at 1 y ear . N o ot her associ at ions. C T ( +R SA ) can qu an tif y t issu e heal ing t hr ough qua nt ify ing t is sue den si ty, al low s assessm ent of re -ru ptu re ri sk . Schepul l et al. [76] Rand om ized cont rol led tr ial 35 A chi lles tendon rupt ur e, su rg ical treat m ent , cas t im m ob iliz at io n com par ed to tens ional loadi ng i n random ized cont rol led tr ial RSA + C T 7, 19 and 52 w eeks C or rel at ion bet w een el ast ic m od ul us and el ongat ion at 7 w eeks an d t he heel -r is e out com e at 52 w eeks. N o ot her s igni ficant cor rel at ions. E last ic m od ul us p red ict s tendon heal ing but m ay no t m at ter in fu nc tio na l o ut co m e. 25 Tab le 4 . S tud ies co ncer ni ng d iag no st ic accur acy d at a St ud ies D esi gn N Pat hol ogy + An aly sis Im ag in g Fol low -u p O ut com e + Im ag in g C har act er ist ics Se ns itiv ity Sp eci fici ty LR + LR- D& B Sc or e G rech en ig et al . [29] C ase -cont rol 72 32 A cut e traum at ic rupt ur es , 40 chr oni c tendon com pl ai nt s, 30 non -inj ur ed U ltr as ound Di ffer ence i n M H z f or ul tras ound ( 5-20 M Hz ), m or e M H z m or e cl ar ity, com par e t o cont ral at er al si de. H igher fr equenci es 100% (29/ 29) (95% C I = 86% -100% ) 0% (0/ 3) (95% C I = 0% -69% ) LR +: 1 .0 LR-: N /A 1185
pat ien ts, int raoper at iv e confir m at ion best fo r an al ysi s o f tendon i ns er tion . G riffi n e t al. [30] Pr os pect iv e case -cont rol 22 24 w ith oper at iv el y confir m ed Achi lles tendon rupt ur e, anal ys is of 22 r upt ur es , com par ison of nov ice and exp er t anal ysi s Real tim e Ac hille s U ltr as ound Thom ps on te st (R AU T) and (st at ic) U ltr as ound (U S) <21 d ays afte r i nj ury , on t he day of s ur ger y 13 -6 M H z t rans ducer . Pat ient s w er e pl aced in t he pr one pos iti on, w ith t he a nk le ha ngi ng fre el y, bi la te ra l exam inat ion. A nal ysi s of 88 s lides (bi lat er al : RA U T and st at ic) . Ex pe rt RA U T: 86. 4% (9 5% C I = 79% -91. 5% ) Expe rt U S: 79. 6% (9 5% C I = 71. 5% -85. 9% ) Exp er t RA U T: 91. 7% (9 5% C I = 85. 2% -95. 6% ) Expe rt U S: 86. 4% (9 5% C I = 79% -91. 5% ) Exp er t RAU T: LR +: 10. 4 LR -: 0. 15 Exp er t U S: LR+:5 .9 LR -:0 .2 20 H ar tger ink et a l. [32] C ase -cont rol 26 Pa rtia l v s. fu ll thi cknes s t ear s U ltr as ound M ean tim e bet w een U S and sur ger y 6. 6 day s f or fu ll an d 21 6 days f or pa rtia l thi ck nes s te ars 7.5 -12 M H z l inear trans ducer , pr one pos iti on, fe et ha ngi ng ov er tabl e. Longi tudi nal and trans ver se pl anes . Tw o fa ls e po si tiv e du e to incom pl et e m edi al to lat er al and s uper ior to inf er ior s cann ing, c an al so b e d ue t o d el ay unt il s ur ger y. 100% (14/ 14) (95% C I = 73% -100% ) 83. 3% (10/ 12) (95% C I = 51% -97% ) LR +: 7 .0 LR-: 0 .0 20 M ar get ic et al . [ 56] C ase -cont rol and pr osp ect ive cohor t 100 C om par e ini tial ul tras ound w ith int raoper at iv e ( fu ll vs. p ar tial rupt ur e) . 88 oper at ed, 12 treat ed conser vat ivel y U ltr as ound 3, 5, 8, and 12 w eeks Li near 7. 5 M H z pr obe. Longi tudi nal and trans ver se pl anes in a st at ic an d dyn am ic vi ew . P at ien t p ro ne, ankl e neut ral , b ot h tendons s canned. U ltr as ound s ignal cor rel at ed w ith clin ic al 90. 6% (78/ 88) (95% C I = 82% -96% ) 100% (2/ 2) (95% C I = 20% -100% ) LR +: N /A LR-: 0.09 15Ultrasound
The mean D&B score of ultrasound studies was 16.4 (SD = 3.99).
The studies that applied ultrasound referred to a transducer in the range of 5-20 MHz
[1,
2, 5–8, 12–14, 17, 21, 27–30, 32, 34, 38, 42, 43, 55–57, 61, 65, 68, 71, 72, 81, 83, 85, 88,
91], with specifically 7.5 MHz being the most frequently chosen frequency [1, 2, 6, 8, 14,
17, 28, 32, 34, 38, 43, 55–57, 61, 65, 71, 72, 85]
(19/32 articles). The frequency of probes
increased moderately in more recent articles (r = 0.42). One study
[29] concluded more
MHz resulted in more clarity and was excluded from frequency vs. time analysis for this
reason.
The applied examination protocol varied per study. The general guideline consisted of
the patient lying prone with their foot hanging over the table (neutral) [2, 5, 8, 12–14, 17,
27, 30, 32, 34, 38, 41, 43, 55–57, 65, 68, 72, 81, 83, 91] and an ultrasound being made of
both the injured and (healthy) contralateral tendon [1, 6–8, 12, 14, 17, 29, 30, 34, 41, 43,
56, 57, 61, 63, 65, 71, 72, 81, 85]. The longitudinal and/or transverse planes were mostly
referenced to [8, 14, 17, 27, 32, 42, 43, 56, 57, 61, 65, 83, 85, 88], although some studies
reported analyzing axial and/or sagittal planes [42, 61, 68, 71, 83, 88]. Most studies
examined the tendon dynamically [2, 5, 6, 8, 30, 34, 39, 42, 45, 56, 63, 68, 71, 88], four
studies performed the examination with the foot in plantarflexion [27, 38, 68, 72].
Studies examining ultrasound’s diagnostic role in patients with Achilles tendon pain
recommended its use. Only one study
[88] discouraged the use of ultrasound due to
the occurrence of false negatives. Ultrasound is said to determine the type (full, partial
or even plantaris tendon) and level of rupture, define the extent of tissue damage and
prognosis as well as aid in providing an indication for treatment selection (surgery or (type
of) conservative treatment [2, 5–7, 14, 29, 30, 32, 34, 38, 39, 42, 45, 56, 65, 68, 88]. In
avoiding diagnostic pitfalls, it is stated that tendon edge apposition is dependent on knee
flexion and foot position [38, 39, 45, 68] and recommended ultrasound be performed
dynamically, in more than one plane, and not immediately post-activity, due to possible
increased blood flow [6, 8, 27].
In terms of its monitoring potential, the results and conclusions of the studies revealed
that ultrasound results show various pathological changes after ATR treatment [1, 7, 8,
12–14, 17, 21, 28, 34, 38, 39, 41, 43, 55–57, 61, 63, 71, 81, 83, 85, 91]. Combining
elastography with ultrasound analysis showed post-ruptured Achilles tendons are
stiffer and have a higher elasticity and more heterogeneous structure [12, 13, 83, 91].
In addition, ATRs show (long term) changes in mechanics (force/strain and stiffness) [1,
12, 28], area [28, 41] and flow on Power Doppler ultrasound (PDUS)
[21]. The studies
confirmed that ultrasound can detect healing and guide decisions after primary treatment
and during rehabilitation [7, 13, 39, 63, 68, 71, 88], provide prognostic information [14,
42, 68, 88], reduce re-rupture incidence [45, 68, 88]
and detect degenerative change in
the contralateral tendon
[12, 63]. No difference was found in tendon structure depending
on treatment (surgical or conservative) from 4 weeks to 63 months [8, 55, 61].
Despite the
articles’ recommendation for ultrasound, the pathology detected is not associated with
clinical or functional deficits. There seemed to be little to no association between tendon
structure on ultrasound and tendon function post-treatment [8, 17, 27, 38, 55, 57, 61, 72,
83]. Rominger et al.
[71] and Margetic et al.
[56] found a significant positive correlation
between ultrasound abnormalities and the patient’s clinical picture and functional
recovery. Agres et al.
[1] determined tendon stiffness had a moderate negative correlation
with altered gait and Suydam et al.
[81] found a moderate correlation between tendon
length on ultrasound and compensatory muscle activation (triceps surae) after ATR.
Four studies [12, 13, 83, 91]
combined ultrasound with elastography, one determining
elasticity values had a very strong positive correlation with functional outcome
[91], one
showing a moderate inverse correlation between stiffness and subjective outcome
[12]
and another that elastography provides additional functional data
[13]. The other articles
were unanimous that ultrasound can define pathology and herewith the possible stage of
tendon healing; this does not show an association with function.
MRI
The mean D&B score of MRI studies was 16.6 (SD = 3.2).
The MRI studies used T1/T2 weighted images. Half (6/12) of the studies referring to Tesla
(T) strength of MRI used a 1.5T machine [5, 16, 24, 31, 43, 44, 61, 73, 75, 90]. There was
a strong positive correlation between the year of the study and the T capabilities of MRI
(r = 0.71). The general examination positioned the patient supine, placed the ankle/foot in
the coil [16, 24, 31, 44, 53, 61, 73, 75] and followed with acquisition of T1/T2 images [5,
16, 24, 31, 69, 71, 73, 74, 86, 90] in axial and sagittal [5, 16, 24, 31, 44, 61, 69, 71, 73–75,
90] and sometimes coronal [5, 16, 74, 75]
planes. Seven studies imaged the contralateral
tendon [16, 43, 44, 53, 61, 71, 74].
Specified foot position ranged from neutral [50, 75] to
plantarflexion [53, 61] to dorsiflexion [16].
Six studies examined MRI as a diagnostic tool [5, 26, 31, 46, 50, 73]. Upon presentation
ruptured tendons were thicker [31, 90] and showed increased external rotation on MRI [50].
Bianchi et al.
[5] determined MRI can diagnose a plantaris tendon tear but recommended
ultrasound since it is faster and cheaper and Garras et al.
[26] discouraged the use of
MRI because it is too costly and time-consuming. As a monitoring modality, MRI is said
to visualize structure, pathology, and normal healing [16, 24, 31, 43, 44, 53, 69, 71, 73,
75, 86, 90], but is said to be too time-consuming or inferior to ultrasound for routine use
[16, 53, 61, 71, 86, 90]. Pathology was reported to be best seen on T2-weighted images
[24, 31, 44, 73, 90]. The operated tendon was stated to be thicker, more heterogeneous
and more irregular [43, 44, 53, 61, 69, 71, 75, 86, 90]. Two studies assessed the tendon
structure in both conservatively and operatively treated, both concluding there to be no
difference after 6 months and 3 years [16, 61].
There seemed to be a limited relationship between MRI signal pathology and tendon
function [16, 31, 53, 61, 69, 86]. Karjalainen et al.
[44] determined a moderate positive
correlation between signal pathology and functional (recovery) at 3/6 months and
also presented data showing the patients with the poorest outcome had the largest
intratendinous signal [43]. Rominger et al.
[71] (also) found that MRI pathology positively
correlated with functional capacity, and Rebeccatto et al.
[69] concluded that a possible
relationship between muscle compartment area on MRI and subjective outcome exists.
Other imaging modalities (X-ray, RSA, CT, OCT, FDG/PET, DTI)
The mean D&B score of studies concerning other modalities was 16.1 (SD = 5.8).
Nine studies investigated other imaging modalities than ultrasound or MRI, determining
their use to be of limited value (X-ray) [6, 66] or complementary (OCT) [4]. Three modalities
(FDG/PET, DTI, and RSA) showed a potentially relevant relation with other recovery
outcomes during ATR monitoring. FDG/PET [21] showed a strong negative correlation (r
= -0.89) between tendon metabolism and subjective outcome, the diffusion coefficients
calculated by DTI had a moderate positive correlation (r = 0.71) with the time patients are
followed up [74] and RSA results showed a moderate correlation at 6-18 weeks (r = 0.76)
and a weak correlation at 1 year (r = 0.41) with tendon function [76, 78].
Diagnostic accuracy
Data on diagnostic accuracy are presented in Table 4 and Figure 2. The sensitivity
of ultrasound ranged from 79.6%-100% [29, 30, 32, 56, 65]. Two ultrasound studies
reported perfect (100%) specificity data [56, 65]. Griffin et al. determined that performing
the Thompson test during ultrasound examination (RAUT) is more sensitive and more
specific than traditional (static) ultrasound
[30]. The LR+ of ultrasound ranged from 1.0-10
(three studies) and LR- from 0-0.23 (four studies).
Two studies provided diagnostic accuracy data on MRI. However, one study had an
absence of false positives and true negatives
[26] and one of true positives
[46], making
half of the calculations unobtainable. The sensitivity and specificity were calculated at
90.9% and 100% respectively. The LR+ of MRI was calculated at 0.91 and LR- at 1.0.
The methodological qualities of the studies varied greatly. Figure 3 shows that the
QUADAS-2 appraisal revealed a high risk of bias in the use of the reference standard.
Additionally, the mean D&B score of the diagnostic accuracy studies proved the lowest
at 15.6 (SD = 4.3). No other imaging modalities than ultrasound or MRI provided data on
diagnostic accuracy.
Figure 2. Plot of sensitivity and specificity 100 80 60 40 20 0 Kuwada 2008 Garras et al. 2012 Paavola et al. 1998 Mar getic et al. 2007 Hartgerink et al. 2001
Griffin et al. 2016 (Static Ultrasound)
Griffin et al. 2016 (RAUT)
Gr echenig et al. 1997 CI of Sensitivity CI of Specificity Sensitivity Specificity
Study
Figure 3. QUADAS-2 scoring of risk of bias and applicability concerns Garras et al. 2012 Grechenig et al. 1997 Griffin et al. 2016 Hartgerink et al. 2001 Kuwada 2008 Margetic et al. 2007 Paavola et al. 1998
Patient Selection Index T
est
Refer
ence Standar
d
Flow and Timing Patient Selection Index T
est
Refer
ence Standar
d
