DISSERTATIONS | ANTTI JAROMA | ASSESSMENT OF BONE AFTER TOTAL KNEE ARTHROPLASTY | No 466
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Dissertations in Health Sciences
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THE UNIVERSITY OF EASTERN FINLAND
ANTTI JAROMA
ASSESSMENT OF BONE AFTER TOTAL KNEE ARTHROPLASTY
Periprosthetic bone remodels after total knee arthroplasty. The main purpose of this
dissertation was to assess the medium- to long-term changes of periprosthetic bones and neighboring joints after total knee arthroplasty.
Dual-energy X-ray absorptiometry can detect periprosthetic bone mineral loss. With this method, we can monitor the effect of bone active
drugs on periprosthetic bone tissue and the changes of the neighboring joints. Cone beam computed tomography is a promising new tool in evaluating quality of the periprosthetic bone
environment and component rotations.
ANTTI JAROMA
ASSESSMENT OF BONE AFTER TOTAL KNEE
ARTHROPLASTY
Antti Jaroma
ASSESSMENT OF BONE AFTER TOTAL KNEE ARTHROPLASTY
To be presented with permission of the Faculty of Health Sciences, University of Eastern Finland for public examination in Kuopio University Hospital
Auditorium I, Kuopio, on Friday, June 15th 2018, at 12.00 hours
Publication of the University of Eastern Finland Dissertations in Health Sciences
Number 466
Department of Orthopaedics, Traumatology and Hand Surgery, School of Medicine, Faculty of Health Sciences, University of Eastern Finland
Kuopio 2018
Antti Jaroma
ASSESSMENT OF BONE AFTER TOTAL KNEE ARTHROPLASTY
To be presented with permission of the Faculty of Health Sciences, University of Eastern Finland for public examination in Kuopio University Hospital
Auditorium I, Kuopio, on Friday, June 15th 2018, at 12.00 hours
Publication of the University of Eastern Finland Dissertations in Health Sciences
Number 466
Department of Orthopaedics, Traumatology and Hand Surgery, School of Medicine, Faculty of Health Sciences, University of Eastern Finland
Kuopio 2018
Series Editors:
Professor Tomi Laitinen, M.D., Ph.D.
Institute of Clinical Medicine, Clinical Physiology and Nuclear Medicine Faculty of Health Sciences
Professor Hannele Turunen, Ph.D.
Department of Nursing Science Faculty of Health Sciences Professor Kai Kaarniranta, M.D., Ph.D.
Institute of Clinical Medicine, Ophthalmology Faculty of Health Sciences
Associate Professor (Tenure Track) Tarja Malm, Ph.D.
A.I. Virtanen Institute for Molecular Sciences Faculty of Health Sciences
Lecturer Veli-Pekka Ranta, Ph.D. (pharmacy) School of Pharmacy
Faculty of Health Sciences Distributor:
University of Eastern Finland Kuopio Campus Library
P.O.Box 1627 FI-70211 Kuopio, Finland http://www.uef.fi/kirjasto
Grano Oy Jyväskylä, 2018
Distributor:
University of Eastern Finland Kuopio Campus Library ISBN: 978-952-61-2801-6 (nid.) ISBN: 978-952-61-2802-3 (PDF)
ISSNL: 1798-5706 ISSN: 1798-5706 ISSN: 1798-5714 (PDF)
Author’s address: Department of Orthopaedics, Traumatology and Hand Surgery, Kuopio University Hospital, Institute of Clinical Medicine, School of Medicine, Faculty of Health Sciences
University of Eastern Finland KUOPIO
FINLAND
Supervisors: Tarja Soininvaara, M.D., Ph.D.
School of Medicine, Faculty of Health Sciences University of Eastern Finland
KUOPIO FINLAND
Professor Heikki Kröger, M.D., Ph.D.
Department of Orthopaedics, Traumatology and Hand Surgery, Department of Surgery, Kuopio University Hospital, Institute of Clinical Medicine, School of Medicine, Faculty of Health Sciences University of Eastern Finland
KUOPIO FINLAND
Reviewers: Docent Antti Eskelinen, M.D., Ph.D.
Faculty of Medicine and Life Sciences University of Tampere
TAMPERE FINLAND
Docent Tuukka Niinimäki, M.D., Ph.D.
Deparment of Orthopaedics and Traumatology Faculty of Medicine
University of Oulu OULU
FINLAND
Opponent: Professor Hannu T Aro, M.D., Ph.D.
Department of Orthopaedic Surgery and Traumatology
University of Turku and Turku University Hospital TURKU
FINLAND
Series Editors:
Professor Tomi Laitinen, M.D., Ph.D.
Institute of Clinical Medicine, Clinical Physiology and Nuclear Medicine Faculty of Health Sciences
Professor Hannele Turunen, Ph.D.
Department of Nursing Science Faculty of Health Sciences Professor Kai Kaarniranta, M.D., Ph.D.
Institute of Clinical Medicine, Ophthalmology Faculty of Health Sciences
Associate Professor (Tenure Track) Tarja Malm, Ph.D.
A.I. Virtanen Institute for Molecular Sciences Faculty of Health Sciences
Lecturer Veli-Pekka Ranta, Ph.D. (pharmacy) School of Pharmacy
Faculty of Health Sciences Distributor:
University of Eastern Finland Kuopio Campus Library
P.O.Box 1627 FI-70211 Kuopio, Finland http://www.uef.fi/kirjasto
Grano Oy Jyväskylä, 2018
Distributor:
University of Eastern Finland Kuopio Campus Library ISBN: 978-952-61-2801-6 (nid.) ISBN: 978-952-61-2802-3 (PDF)
ISSNL: 1798-5706 ISSN: 1798-5706 ISSN: 1798-5714 (PDF)
Author’s address: Department of Orthopaedics, Traumatology and Hand Surgery, Kuopio University Hospital, Institute of Clinical Medicine, School of Medicine, Faculty of Health Sciences
University of Eastern Finland KUOPIO
FINLAND
Supervisors: Tarja Soininvaara, M.D., Ph.D.
School of Medicine, Faculty of Health Sciences University of Eastern Finland
KUOPIO FINLAND
Professor Heikki Kröger, M.D., Ph.D.
Department of Orthopaedics, Traumatology and Hand Surgery, Department of Surgery, Kuopio University Hospital, Institute of Clinical Medicine, School of Medicine, Faculty of Health Sciences University of Eastern Finland
KUOPIO FINLAND
Reviewers: Docent Antti Eskelinen, M.D., Ph.D.
Faculty of Medicine and Life Sciences University of Tampere
TAMPERE FINLAND
Docent Tuukka Niinimäki, M.D., Ph.D.
Deparment of Orthopaedics and Traumatology Faculty of Medicine
University of Oulu OULU
FINLAND
Opponent: Professor Hannu T Aro, M.D., Ph.D.
Department of Orthopaedic Surgery and Traumatology
University of Turku and Turku University Hospital TURKU
FINLAND
To Aarne, Reeta, Ellinoora and Henna
Jaroma, Antti
Assessment of Bone After Total Knee Arthroplasty University of Eastern Finland, Faculty of Health Sciences Publications of the University of Eastern Finland.
Dissertation in Health Sciences; 466. 2018. 78 p.
ISBN: 978-952-61-2801-6 (print) ISSNL: 1798-5706
ISSN: 1798-5706
ISBN: 978-952-61-2802-3 (PDF) ISSN: 1798-5714 (PDF)
ABSTRACT
Background: Total knee arthroplasty (TKA) provides pain relief and improves function in patients with knee osteoarthrosis (OA). Dual X-ray Absorptiometry (DXA) allows us to detect periprosthetic bone mineral loss after implantation of the prosthesis and examine bone mineral density (BMD) changes of the neighboring joints (hips and contralateral knee) after TKA. Cone beam computed tomography (CBCT) is a promising new tool in evaluating quality of the periprosthetic bone environment and TKA component rotations.
Subjects and Methods: Periprosthetic tibial BMD (n=86) and the effect of alen- dronate treatment on periprosthetic femoral and tibial BMD (n= 26) were followed up to seven years and BMD of the hips and contralateral knee (n=38) up to four years postoperatively. CBCT of TKA knees scheduled for revision knee arthroplasty (n=18) were conducted the day before surgery and assessed by an orthopedic sur- geon and two musculoskeletal radiologists.
Results: The mean baseline BMD of the medial metaphyseal region of interest (ROI) was higher in the preoperatively varus-aligned group than in the valgus- aligned group (25%, p<0.001) and remained higher throughout the follow-up (23%, p<0.002 in 7 years). There was a significant decrease of mean periprosthetic BMDs of the medial metaphyseal ROIs in both preoperatively varus- and valgus-aligned knees (13%, p<0.001 and 12%, p=0.02 respectively). In the postoperative valgus sub- group of preoperatively varus-aligned knees, the decrease of BMD in medial met- aphyseal ROI was greatest (24%, p<0.001 in 7 years). The alendronate group showed significantly higher BMD in the anterior metaphyseal ROI at 4 years p=0.002) and in the posterior metaphyseal ROI 2 years (p= 0.024). At the seven-year measurement, the alendronate group showed significantly higher BMD in the lat- eral metaphyseal tibial ROI (p=0.024). In the hip of the affected side, there were no significant changes of the BMDs in any measured ROIs throughout the four-years follow-up. In contralateral hip, there was a significant decrease of femoral neck (3.3%, p < 0.01) and total femoral (3.0%, p < 0.001) BMDs. In the contralateral knee,
To Aarne, Reeta, Ellinoora and Henna
Jaroma, Antti
Assessment of Bone After Total Knee Arthroplasty University of Eastern Finland, Faculty of Health Sciences Publications of the University of Eastern Finland.
Dissertation in Health Sciences; 466. 2018. 78 p.
ISBN: 978-952-61-2801-6 (print) ISSNL: 1798-5706
ISSN: 1798-5706
ISBN: 978-952-61-2802-3 (PDF) ISSN: 1798-5714 (PDF)
ABSTRACT
Background: Total knee arthroplasty (TKA) provides pain relief and improves function in patients with knee osteoarthrosis (OA). Dual X-ray Absorptiometry (DXA) allows us to detect periprosthetic bone mineral loss after implantation of the prosthesis and examine bone mineral density (BMD) changes of the neighboring joints (hips and contralateral knee) after TKA. Cone beam computed tomography (CBCT) is a promising new tool in evaluating quality of the periprosthetic bone environment and TKA component rotations.
Subjects and Methods: Periprosthetic tibial BMD (n=86) and the effect of alen- dronate treatment on periprosthetic femoral and tibial BMD (n= 26) were followed up to seven years and BMD of the hips and contralateral knee (n=38) up to four years postoperatively. CBCT of TKA knees scheduled for revision knee arthroplasty (n=18) were conducted the day before surgery and assessed by an orthopedic sur- geon and two musculoskeletal radiologists.
Results: The mean baseline BMD of the medial metaphyseal region of interest (ROI) was higher in the preoperatively varus-aligned group than in the valgus- aligned group (25%, p<0.001) and remained higher throughout the follow-up (23%, p<0.002 in 7 years). There was a significant decrease of mean periprosthetic BMDs of the medial metaphyseal ROIs in both preoperatively varus- and valgus-aligned knees (13%, p<0.001 and 12%, p=0.02 respectively). In the postoperative valgus sub- group of preoperatively varus-aligned knees, the decrease of BMD in medial met- aphyseal ROI was greatest (24%, p<0.001 in 7 years). The alendronate group showed significantly higher BMD in the anterior metaphyseal ROI at 4 years p=0.002) and in the posterior metaphyseal ROI 2 years (p= 0.024). At the seven-year measurement, the alendronate group showed significantly higher BMD in the lat- eral metaphyseal tibial ROI (p=0.024). In the hip of the affected side, there were no significant changes of the BMDs in any measured ROIs throughout the four-years follow-up. In contralateral hip, there was a significant decrease of femoral neck (3.3%, p < 0.01) and total femoral (3.0%, p < 0.001) BMDs. In the contralateral knee,
there were significant BMD decreases up to four years in anterior metaphyseal (5.0%, p < 0.001), total femoral metaphyseal (3.6%, p < 0.001) and femoral diaphyseal (5.1%, p < 0.001) ROIs compared to baseline. The interobserver reliability for femo- ral component rotation was moderate. The overall ICC between the three investi- gators was 0.41 (95% confidence interval 0.12-0.69). For tibial component, the ICC was 0.87 (0.74-0.94) corresponding a very good interobserver reliability. The in- traobserver reliabilities were good for femoral component (ICC=0.70, 95% CI 0.35- 0.87) and very good for tibial component (ICC=0.92, 95% CI 0.80-0.97). The sensitivi- ty and specificity for tibial component loosening were 97% and 85% respectively.
Conclusions: Both DXA and CBCT allow assessment of the quality of periprosthetic bone after TKA. The decrease in BMD of the more loaded medial condyle in patients with OA of the medial compartment of the knee results in more balanced bone stock below the tibial tray. Bisphosphonate treatment together with calcium for one year following a TKA operation has a positive effect on BMD up to four years postoperatively. TKA did not increase the BMD values of the hips or the contralateral knee. However, it seemed to stabilize BMD of the hip on the affected side. CBCT scanning provides reliable and repeatable data for determining the rotation of femoral and tibial components, while also showing minor overestimation of tibial component loosening.
National Library of Medicine Classification: QU 100, WE 141, WE 202, WE 874, WN 206 Medical Subject Headings: Absorptiometry, Photon; Arthroplasty, Replacement, Knee;
Bone Density; Cone-Beam Computed Tomography; Osteoarthritis, Knee
Jaroma, Antti
Luun tutkiminen polven tekonivelleikkauksen jälkeen Itä-Suomen yliopisto, Terveystieteiden tiedekunta Publications of the University of Eastern Finland.
Dissertation in Health Sciences; 466. 2018. 78 s.
ISBN: 978-952-61-2801-6 (nid.) ISSNL: 1798-5706
ISSN: 1798-5706
ISBN: 978-952-61-2802-3 (PDF) ISSN: 1798-5714 (PDF)
TIIVISTELMÄ
Tutkimuksen tausta: Polven tekonivelleikkaus vähentää nivelrikkoa sairastavien potilaiden kipua ja parantaa heidän toimintakykyään. Leikkauksen jälkeen teko- niveltä lähellä oleva luukudos alkaa muovautua. Muovautumisen seurauksena syntyviä luuntiheyden muutoksia voidaan mitata ns. kaksienergiaisella röntgenab- sorptiometrialla (Dual X-ray Absorptiometry, DXA). Menetelmä soveltuu vastaa- vasti myös muiden kantavien nivelten luuntiheyden muutosten mittaamiseen. Kar- tiokeilatietokonetomografia (KKTT) on uusi lupaava luun kuvantamiseen käytetty menetelmä ja sillä voi olla mahdollista kuvata myös tekoniveltä sekä sitä lähellä olevaa luukudosta.
Aineisto ja menetelmät: Tutkimukseen rekrytoitiin 86 polven tekonivelleik- kaukseen kutsuttua potilasta. Leikkauksen jälkeen potilaiden sääriluun yläosan tekoniveltä lähellä olevaa luuntiheyttä seurattiin seitsemän vuoden ajan. Tutkimuk- sen potilaista 38:lta mitattiin myös leikatun raajan lonkan alueen ja leikkaamatto- man raajan lonkan sekä polven alueen luuntiheys neljän vuoden ajan leikkauksesta.
Toisessa tutkimuksessa 26 potilasta satunnaistettiin saamaan alendronaatti- ja kal- siumhoitoa tai pelkästään kalsiumhoitoa vuoden ajan tekonivelleikkauksen jälkeen, ja heidän polven alueen tekoniveltä lähellä olevan luun tiheyttä seurattiin seitse- män vuoden ajan leikkauksesta. 18:lta potilaalta, jotka kutsuttiin polven tekonive- len uusintaleikkaukseen, kuvattiin leikattava polvi KKTT:lla. Ortopedian erikois- lääkäri ja kaksi tuki- ja liikuntaelinradiologian erikoislääkäriä arvioivat otetut KKTT-kuvat.
Tulokset: Tekoniveltä lähellä olevan sääriluun sisäyläosan luuntiheyden keskiar- vo oli välittömästi leikkauksen jälkeen korkeampi niillä potilailla, joilla alaraaja oli ennen leikkausta ollut ns. varus-virheasennossa (polvi kääntyy keskiasennosta ulospäin), kuin potilailla, joilla alaraajan virheasento oli ennen leikkausta ns. valgus (keskiasennosta sisäänpäin) (25%, p<0,001). Mitattu ero säilyi tilastollisesti merkit- sevänä koko seurannan ajan (23%, p<0,002 seitsemän vuotta leikkauksesta). Mo- lempien ryhmien sääriluun yläsisäosan luuntiheyden keskiarvo laski seuranta- aikana tilastollisesti merkitsevästi (13%, p<0,001 varus-potilailla ja 12%, p=0,02 val-
there were significant BMD decreases up to four years in anterior metaphyseal (5.0%, p < 0.001), total femoral metaphyseal (3.6%, p < 0.001) and femoral diaphyseal (5.1%, p < 0.001) ROIs compared to baseline. The interobserver reliability for femo- ral component rotation was moderate. The overall ICC between the three investi- gators was 0.41 (95% confidence interval 0.12-0.69). For tibial component, the ICC was 0.87 (0.74-0.94) corresponding a very good interobserver reliability. The in- traobserver reliabilities were good for femoral component (ICC=0.70, 95% CI 0.35- 0.87) and very good for tibial component (ICC=0.92, 95% CI 0.80-0.97). The sensitivi- ty and specificity for tibial component loosening were 97% and 85% respectively.
Conclusions: Both DXA and CBCT allow assessment of the quality of periprosthetic bone after TKA. The decrease in BMD of the more loaded medial condyle in patients with OA of the medial compartment of the knee results in more balanced bone stock below the tibial tray. Bisphosphonate treatment together with calcium for one year following a TKA operation has a positive effect on BMD up to four years postoperatively. TKA did not increase the BMD values of the hips or the contralateral knee. However, it seemed to stabilize BMD of the hip on the affected side. CBCT scanning provides reliable and repeatable data for determining the rotation of femoral and tibial components, while also showing minor overestimation of tibial component loosening.
National Library of Medicine Classification: QU 100, WE 141, WE 202, WE 874, WN 206 Medical Subject Headings: Absorptiometry, Photon; Arthroplasty, Replacement, Knee;
Bone Density; Cone-Beam Computed Tomography; Osteoarthritis, Knee
Jaroma, Antti
Luun tutkiminen polven tekonivelleikkauksen jälkeen Itä-Suomen yliopisto, Terveystieteiden tiedekunta Publications of the University of Eastern Finland.
Dissertation in Health Sciences; 466. 2018. 78 s.
ISBN: 978-952-61-2801-6 (nid.) ISSNL: 1798-5706
ISSN: 1798-5706
ISBN: 978-952-61-2802-3 (PDF) ISSN: 1798-5714 (PDF)
TIIVISTELMÄ
Tutkimuksen tausta: Polven tekonivelleikkaus vähentää nivelrikkoa sairastavien potilaiden kipua ja parantaa heidän toimintakykyään. Leikkauksen jälkeen teko- niveltä lähellä oleva luukudos alkaa muovautua. Muovautumisen seurauksena syntyviä luuntiheyden muutoksia voidaan mitata ns. kaksienergiaisella röntgenab- sorptiometrialla (Dual X-ray Absorptiometry, DXA). Menetelmä soveltuu vastaa- vasti myös muiden kantavien nivelten luuntiheyden muutosten mittaamiseen. Kar- tiokeilatietokonetomografia (KKTT) on uusi lupaava luun kuvantamiseen käytetty menetelmä ja sillä voi olla mahdollista kuvata myös tekoniveltä sekä sitä lähellä olevaa luukudosta.
Aineisto ja menetelmät: Tutkimukseen rekrytoitiin 86 polven tekonivelleik- kaukseen kutsuttua potilasta. Leikkauksen jälkeen potilaiden sääriluun yläosan tekoniveltä lähellä olevaa luuntiheyttä seurattiin seitsemän vuoden ajan. Tutkimuk- sen potilaista 38:lta mitattiin myös leikatun raajan lonkan alueen ja leikkaamatto- man raajan lonkan sekä polven alueen luuntiheys neljän vuoden ajan leikkauksesta.
Toisessa tutkimuksessa 26 potilasta satunnaistettiin saamaan alendronaatti- ja kal- siumhoitoa tai pelkästään kalsiumhoitoa vuoden ajan tekonivelleikkauksen jälkeen, ja heidän polven alueen tekoniveltä lähellä olevan luun tiheyttä seurattiin seitse- män vuoden ajan leikkauksesta. 18:lta potilaalta, jotka kutsuttiin polven tekonive- len uusintaleikkaukseen, kuvattiin leikattava polvi KKTT:lla. Ortopedian erikois- lääkäri ja kaksi tuki- ja liikuntaelinradiologian erikoislääkäriä arvioivat otetut KKTT-kuvat.
Tulokset: Tekoniveltä lähellä olevan sääriluun sisäyläosan luuntiheyden keskiar- vo oli välittömästi leikkauksen jälkeen korkeampi niillä potilailla, joilla alaraaja oli ennen leikkausta ollut ns. varus-virheasennossa (polvi kääntyy keskiasennosta ulospäin), kuin potilailla, joilla alaraajan virheasento oli ennen leikkausta ns. valgus (keskiasennosta sisäänpäin) (25%, p<0,001). Mitattu ero säilyi tilastollisesti merkit- sevänä koko seurannan ajan (23%, p<0,002 seitsemän vuotta leikkauksesta). Mo- lempien ryhmien sääriluun yläsisäosan luuntiheyden keskiarvo laski seuranta- aikana tilastollisesti merkitsevästi (13%, p<0,001 varus-potilailla ja 12%, p=0,02 val-
gus-potilailla). Potilaat, joilla alaraajan virheasento oli ennen leikkausta varus- suuntainen, jaettiin edelleen alaryhmiin leikkauksen jälkeisen raajan mekaanisen akselin mukaan. Alaryhmässä, jossa leikkauksen jälkeinen alaraajan asento oli yli- korjaantunut valgus-virheasentoon, laski sääriluun yläsisäosan tekonivelen alla oleva luuntiheys kaikkein eniten (24%, p<0,001 seitsemän vuoden kohdalla).
Reisiluun alaetuosan luuntiheyden keskiarvo oli tilastollisesti merkitsevästi kor- keampi neljään vuoteen saakka leikkauksesta siinä potilasryhmässä, joka sai leik- kauksen jälkeen alendronaatti- ja kalsiumhoitoa verrattuna pelkästään kalsiumhoi- toa saaneeseen ryhmään (p=0,002). Vastaava ero nähtiin reisiluun alatakaosan luun- tiheydessä kahteen vuoteen saakka leikkauksesta (p=0,024) ja sääriluun yläulko- osan luun tiheydessä seitsemän vuoden kohdalla (p=0,024).
Leikatun raajan lonkan luuntiheys säilyi neljän vuoden seurannan aikana muut- tumattomana, kun taas leikkaamattoman raajan lonkassa havaittiin tilastollisesti merkitsevä luuntiheyden väheneminen (3,3%, p < 0,01 reisiluun kaulassa ja 3,0%, p
< 0,001 koko reisiluun yläosassa). Leikkaamattoman polven reisiluun alaosan luun- tiheys väheni neljän vuoden seurannan aikana tilastollisesti merkitsevästi (etuosa 5,0%, p < 0,001, koko reisiluun alaosa 3,6%, p < 0,001 ja reisiluun varsi 5,1%, p <
0,001).
Eri tutkijoiden tutkimustulosten keskinäinen luotettavuus osoittautui keskinker- taiseksi arvioitaessa polviproteesin reisikomponentin rotaatiota (ICC=0,41, 95%
luottamusväli [CI] 0,12-0,69) ja erittäin hyväksi arvioitaessa säärikomponentin ro- taatiota (ICC=0,87, 95% [CI] 0,74-0,94). Yhden tutkijan tutkimustulosten välinen luotettavuus osoittautui reisikomponentin rotaation osalta hyväksi (ICC=0,70, 95%
[CI] 0,35-0,87) ja säärikomponentin osalta erittäin hyväksi (ICC=0,92, 95% [CI] 0,80- 0,97). KKTT osoitti säärikomponentin irtoamisen 97%:n herkkyydellä (sensitiivi- syys) ja 85%:n tarkkuudella (spesifisyys).
Yhteenveto: Sekä DXA että KKTT soveltuvat menetelminä polviproteesia lähellä olevan luun laadun tutkimiseen. Ennen tekonivelleikkausta leikkausta suuremmalle mekaaniselle kuormitukselle joutuneen polven nivelrikkopotilaan sääriluun yläsisäosan luun tiheyden väheneminen aiheuttaa säärikomponentin alaisen luuntiheyden tasapainottumista. Polviproteesileikkausen jälkeisen vuodenmittaisen alendronaattihoidon voitiin havaita lisäävän proteesin viereistä luuntiheyttä, ja vaikutus oli havaittavissa luuntiheysmittauksin neljään vuoteen saakka leikkauksesta. Polven tekonivelleikkaus ei kyennyt lisäämään lonkkien tai leikkaamattoman polven luuntiheyttä, mutta se vakautti leikatun raajan puoleisen lonkan luuntiheyden. KKTT:n avulla voidaan luotettavasti ja toistettavasti määrittää tekonivelkomponenttien rotaatiot, mutta tutkimus voi yliarvioida säärikomponentin irtoamista.
Yleinen suomalainen asiasanasto: kartiokeilatomografia; leikkaushoito; luuntiheys;
nivelrikko; polvet; tekonivelet FinMeSH: Fotoniabsorptiotekniikka
ACKNOWLEDGEMENTS
The present study was carried out at the Departments of Surgery, Clinical Physiology and Nuclear Medicine, Orthopaedics, Traumatology and Hand Surgery, and Radiology of Kuopio University Hospital.
I owe my most sincere gratitude and respect to my supervisor Tarja Soininvaara, M.D., Ph.D. for introducing me to scientific research and providing me the opportunity to work under her guidance. I am also thankful for her basic work for collecting the data of the Knee DXA-study, which was the true foundation of this thesis. I truly admire your knowledge and expertise concerning the bone mineral density research. You were most supportive from the beginning of my research and quided me through the hard times. I always got a rapid response, no matter how busy you were in your own tasks.
I am eternally thankful for my other supervisor, Professor Heikki Kröger for his guidance. You have the ablility to separate the wheat from the chaff and could repeatably support me by responding and solving my problems no matter how foolish they were or what time of the day it was. I wonder if you ever rest. Your enthusiasm towards research is something that keeps on arousing admiration and your skills and knowledge in the field of bone research are unparalleled.
I warmly thank the experts of musculosceletal radiology, Lea Niemitukia, M.D.
and Juha-Sampo Suomalainen M.D. for enabling the knee revision CBCT study of this thesis. Despite the haste of your own clinical work, you were ready to take these time consuming tasks of image interpretation and revising the manuscript. I am grateful that I had the opportunity to do the scientific work together with you.
The combination of decades of experience with the ethusiasm of youth made you an unbeatable team.
I want to thank Professor Jari Salo for introducing me the opportunity to carry out the knee revision CBCT study and even providing me funding to enable it. I respect your interest in the field of orthopaedic imaging technology while your primary expertice lies in the field of clinical orthopaedics.
From the very beginning of the Knee DXA study, there were key persons to whom I own my gratitude. Professor Jukka Jurvelin, Ph.D., gave his technical and practical advice for providing the mathematical formula and basis of the study.
Docent Hannu Miettinen, M.D., Ph.D., Head of the Department of Orthopaedics, Traumatology and Hand Surgery has also been a key person from the beginning of the study, already for two decades. He has also played the key role in enabling me to carry out the scientific work in the middle of hasty times in the joint replacement unit of our hospital.
I owe my deepest gratitude to my official reviewers, Docent Antti Eskelinen, M.D., Ph.D. from University Hospital of Tampere and Docent Tuukka Niinimäki,
gus-potilailla). Potilaat, joilla alaraajan virheasento oli ennen leikkausta varus- suuntainen, jaettiin edelleen alaryhmiin leikkauksen jälkeisen raajan mekaanisen akselin mukaan. Alaryhmässä, jossa leikkauksen jälkeinen alaraajan asento oli yli- korjaantunut valgus-virheasentoon, laski sääriluun yläsisäosan tekonivelen alla oleva luuntiheys kaikkein eniten (24%, p<0,001 seitsemän vuoden kohdalla).
Reisiluun alaetuosan luuntiheyden keskiarvo oli tilastollisesti merkitsevästi kor- keampi neljään vuoteen saakka leikkauksesta siinä potilasryhmässä, joka sai leik- kauksen jälkeen alendronaatti- ja kalsiumhoitoa verrattuna pelkästään kalsiumhoi- toa saaneeseen ryhmään (p=0,002). Vastaava ero nähtiin reisiluun alatakaosan luun- tiheydessä kahteen vuoteen saakka leikkauksesta (p=0,024) ja sääriluun yläulko- osan luun tiheydessä seitsemän vuoden kohdalla (p=0,024).
Leikatun raajan lonkan luuntiheys säilyi neljän vuoden seurannan aikana muut- tumattomana, kun taas leikkaamattoman raajan lonkassa havaittiin tilastollisesti merkitsevä luuntiheyden väheneminen (3,3%, p < 0,01 reisiluun kaulassa ja 3,0%, p
< 0,001 koko reisiluun yläosassa). Leikkaamattoman polven reisiluun alaosan luun- tiheys väheni neljän vuoden seurannan aikana tilastollisesti merkitsevästi (etuosa 5,0%, p < 0,001, koko reisiluun alaosa 3,6%, p < 0,001 ja reisiluun varsi 5,1%, p <
0,001).
Eri tutkijoiden tutkimustulosten keskinäinen luotettavuus osoittautui keskinker- taiseksi arvioitaessa polviproteesin reisikomponentin rotaatiota (ICC=0,41, 95%
luottamusväli [CI] 0,12-0,69) ja erittäin hyväksi arvioitaessa säärikomponentin ro- taatiota (ICC=0,87, 95% [CI] 0,74-0,94). Yhden tutkijan tutkimustulosten välinen luotettavuus osoittautui reisikomponentin rotaation osalta hyväksi (ICC=0,70, 95%
[CI] 0,35-0,87) ja säärikomponentin osalta erittäin hyväksi (ICC=0,92, 95% [CI] 0,80- 0,97). KKTT osoitti säärikomponentin irtoamisen 97%:n herkkyydellä (sensitiivi- syys) ja 85%:n tarkkuudella (spesifisyys).
Yhteenveto: Sekä DXA että KKTT soveltuvat menetelminä polviproteesia lähellä olevan luun laadun tutkimiseen. Ennen tekonivelleikkausta leikkausta suuremmalle mekaaniselle kuormitukselle joutuneen polven nivelrikkopotilaan sääriluun yläsisäosan luun tiheyden väheneminen aiheuttaa säärikomponentin alaisen luuntiheyden tasapainottumista. Polviproteesileikkausen jälkeisen vuodenmittaisen alendronaattihoidon voitiin havaita lisäävän proteesin viereistä luuntiheyttä, ja vaikutus oli havaittavissa luuntiheysmittauksin neljään vuoteen saakka leikkauksesta. Polven tekonivelleikkaus ei kyennyt lisäämään lonkkien tai leikkaamattoman polven luuntiheyttä, mutta se vakautti leikatun raajan puoleisen lonkan luuntiheyden. KKTT:n avulla voidaan luotettavasti ja toistettavasti määrittää tekonivelkomponenttien rotaatiot, mutta tutkimus voi yliarvioida säärikomponentin irtoamista.
Yleinen suomalainen asiasanasto: kartiokeilatomografia; leikkaushoito; luuntiheys;
nivelrikko; polvet; tekonivelet FinMeSH: Fotoniabsorptiotekniikka
ACKNOWLEDGEMENTS
The present study was carried out at the Departments of Surgery, Clinical Physiology and Nuclear Medicine, Orthopaedics, Traumatology and Hand Surgery, and Radiology of Kuopio University Hospital.
I owe my most sincere gratitude and respect to my supervisor Tarja Soininvaara, M.D., Ph.D. for introducing me to scientific research and providing me the opportunity to work under her guidance. I am also thankful for her basic work for collecting the data of the Knee DXA-study, which was the true foundation of this thesis. I truly admire your knowledge and expertise concerning the bone mineral density research. You were most supportive from the beginning of my research and quided me through the hard times. I always got a rapid response, no matter how busy you were in your own tasks.
I am eternally thankful for my other supervisor, Professor Heikki Kröger for his guidance. You have the ablility to separate the wheat from the chaff and could repeatably support me by responding and solving my problems no matter how foolish they were or what time of the day it was. I wonder if you ever rest. Your enthusiasm towards research is something that keeps on arousing admiration and your skills and knowledge in the field of bone research are unparalleled.
I warmly thank the experts of musculosceletal radiology, Lea Niemitukia, M.D.
and Juha-Sampo Suomalainen M.D. for enabling the knee revision CBCT study of this thesis. Despite the haste of your own clinical work, you were ready to take these time consuming tasks of image interpretation and revising the manuscript. I am grateful that I had the opportunity to do the scientific work together with you.
The combination of decades of experience with the ethusiasm of youth made you an unbeatable team.
I want to thank Professor Jari Salo for introducing me the opportunity to carry out the knee revision CBCT study and even providing me funding to enable it. I respect your interest in the field of orthopaedic imaging technology while your primary expertice lies in the field of clinical orthopaedics.
From the very beginning of the Knee DXA study, there were key persons to whom I own my gratitude. Professor Jukka Jurvelin, Ph.D., gave his technical and practical advice for providing the mathematical formula and basis of the study.
Docent Hannu Miettinen, M.D., Ph.D., Head of the Department of Orthopaedics, Traumatology and Hand Surgery has also been a key person from the beginning of the study, already for two decades. He has also played the key role in enabling me to carry out the scientific work in the middle of hasty times in the joint replacement unit of our hospital.
I owe my deepest gratitude to my official reviewers, Docent Antti Eskelinen, M.D., Ph.D. from University Hospital of Tampere and Docent Tuukka Niinimäki,
M.D., Ph.D. from University Hospital of Oulu for their constructive critisism and advice in the reviewing process of this thesis.
I warmly thank the study personnel, Raija Kantanen R.N. and Eila Koski R.N.
for their technical assistance in the beginning of the study, and Elina Jalava R.N. for your assistace throughout the period of my own scientific work. I also thank Merja Perankoski, Assistant head nurse, Department of Radiology for her assistance in the knee revision CBCT study.
I owe my sincere thanks to biostatisticians Marja-Leena Lamidi and Tuomas Selander for their assistace in statistics, the field where a clinician is, more or less, lost without quidance. I express my special thanks to physicist Hanna Matikka for radiation dose calculations in the home sthrech of the knee revision CBCT study. I also thank Xiaoyu Tong, Ph.D. for his skills with images.
I extent my gratitude to David Laaksonen, M.D., Ph.D. for his careful language revision of this thesis.
I want to thank all the patients who participated in this study.
I was very lucky to have magnificient colleagues in the beginning of my orthopaedic career in Central Hospital of Central Finland, Jyväskylä. I thank you all for believing in me and encouraging me when a was a novice. Especially I want to thank my first tutor Esa Anttila, M.D., orthopaedic surgeon and Docent Maija Pesola, M.D., Ph. D., Head of the Orthopaedics, for introducing me the first steps on the increadible path of joint replacement surgery.
I sincerely thank all my present and former colleagues in the Department of Orthopaedics, Traumatology and Hand Surgery in Kuopio University Hospital. I owe my special gratitude to those joint replacement surgeons, who participated in data collection and operations of the patients in this study.
Thank you for the music, Antti Joukainen, M.D., Ph.D., scientist, friend, colleague and musician of the best quality. Whatever you intend, you accomplish with the greatest enthusiasm, which keeps the others, me included, going on.
My dearest regards to a very special group of colleagues, “the Intimate Association of Licenced Medicians of Kuopio (KuLLI ry)”. You have given me the opportunity to leave all the troubles of the everyday life behind for a while every time we had had a chance to meet each other. You have designated me the meaning of the true friendship.
I have had an opportunity to have a lasting friendship with a lovely female colleaque group of “Viiteryhmä” along with their families and especially their husbands. Together we have been living through the very busy years between the hard work and family life with support to each other. Especially I caress the many mutual, even though mostly cold and rainy midsummer memories.
I owe my deepest thanks to my dear mother-in-law Marja-Leena Kärkkäinen and my father-in-law Teuvo Kärkkäinen in memoriam. I could not have imagined better parents-in-law than you have been to me. I also thank the families of Susanna and Lasse Hydén, Ulla and Jarno Paldanius and Jenni and Hannu Hautakoski.
I warmly thank the lifetime support of my sister Kerttuliisa Jaroma and my brothers Kustaa and Jussi Jaroma along with my brother-in-law Michael Slotte and sisters-in-law Jaana and Marianne Jaroma and your families. You sincerely are yourselves, which make you all very special persons to me.
I express my deepest gratitude and respect to my dear father Heikki Jaroma, who has not only been a loving and caring parent, but also an excellent example as a doctor. Along with your talent and skill, your natural, humane confrontation with your patients has been a guideline to me in my work as a doctor. I warmly thank you Anneli Jaroma, not only for saving my father when the times where hard, but also for being a grandmother to my children. And my mother Marjatta, I know you are there, looking after me from the eternity. Now you can be “so-o proud of me”.
Finally, I owe the deepest possible love to my family. Aarne, Reeta and Ellinoora, you are the rays of sunlight in my life. You make it all worthwhile.
Henna, you mean everything to me. Thank you for your love as a wife and your understanding support as a colleague and a scientist. It has been a priviledge to have you by my side for the majority of my life. I am planning to grow old with you. I love you.
This study was supported financially by Kuopio University Hospital EVO-grants, the State Research Fund of Finland, Carmen Knee Project, Kuopio University Hospital Research Foundation and the Vappu Uuspää Foundation.
Kuopio, April 2018 Antti Jaroma
M.D., Ph.D. from University Hospital of Oulu for their constructive critisism and advice in the reviewing process of this thesis.
I warmly thank the study personnel, Raija Kantanen R.N. and Eila Koski R.N.
for their technical assistance in the beginning of the study, and Elina Jalava R.N. for your assistace throughout the period of my own scientific work. I also thank Merja Perankoski, Assistant head nurse, Department of Radiology for her assistance in the knee revision CBCT study.
I owe my sincere thanks to biostatisticians Marja-Leena Lamidi and Tuomas Selander for their assistace in statistics, the field where a clinician is, more or less, lost without quidance. I express my special thanks to physicist Hanna Matikka for radiation dose calculations in the home sthrech of the knee revision CBCT study. I also thank Xiaoyu Tong, Ph.D. for his skills with images.
I extent my gratitude to David Laaksonen, M.D., Ph.D. for his careful language revision of this thesis.
I want to thank all the patients who participated in this study.
I was very lucky to have magnificient colleagues in the beginning of my orthopaedic career in Central Hospital of Central Finland, Jyväskylä. I thank you all for believing in me and encouraging me when a was a novice. Especially I want to thank my first tutor Esa Anttila, M.D., orthopaedic surgeon and Docent Maija Pesola, M.D., Ph. D., Head of the Orthopaedics, for introducing me the first steps on the increadible path of joint replacement surgery.
I sincerely thank all my present and former colleagues in the Department of Orthopaedics, Traumatology and Hand Surgery in Kuopio University Hospital. I owe my special gratitude to those joint replacement surgeons, who participated in data collection and operations of the patients in this study.
Thank you for the music, Antti Joukainen, M.D., Ph.D., scientist, friend, colleague and musician of the best quality. Whatever you intend, you accomplish with the greatest enthusiasm, which keeps the others, me included, going on.
My dearest regards to a very special group of colleagues, “the Intimate Association of Licenced Medicians of Kuopio (KuLLI ry)”. You have given me the opportunity to leave all the troubles of the everyday life behind for a while every time we had had a chance to meet each other. You have designated me the meaning of the true friendship.
I have had an opportunity to have a lasting friendship with a lovely female colleaque group of “Viiteryhmä” along with their families and especially their husbands. Together we have been living through the very busy years between the hard work and family life with support to each other. Especially I caress the many mutual, even though mostly cold and rainy midsummer memories.
I owe my deepest thanks to my dear mother-in-law Marja-Leena Kärkkäinen and my father-in-law Teuvo Kärkkäinen in memoriam. I could not have imagined better parents-in-law than you have been to me. I also thank the families of Susanna and Lasse Hydén, Ulla and Jarno Paldanius and Jenni and Hannu Hautakoski.
I warmly thank the lifetime support of my sister Kerttuliisa Jaroma and my brothers Kustaa and Jussi Jaroma along with my brother-in-law Michael Slotte and sisters-in-law Jaana and Marianne Jaroma and your families. You sincerely are yourselves, which make you all very special persons to me.
I express my deepest gratitude and respect to my dear father Heikki Jaroma, who has not only been a loving and caring parent, but also an excellent example as a doctor. Along with your talent and skill, your natural, humane confrontation with your patients has been a guideline to me in my work as a doctor. I warmly thank you Anneli Jaroma, not only for saving my father when the times where hard, but also for being a grandmother to my children. And my mother Marjatta, I know you are there, looking after me from the eternity. Now you can be “so-o proud of me”.
Finally, I owe the deepest possible love to my family. Aarne, Reeta and Ellinoora, you are the rays of sunlight in my life. You make it all worthwhile.
Henna, you mean everything to me. Thank you for your love as a wife and your understanding support as a colleague and a scientist. It has been a priviledge to have you by my side for the majority of my life. I am planning to grow old with you. I love you.
This study was supported financially by Kuopio University Hospital EVO-grants, the State Research Fund of Finland, Carmen Knee Project, Kuopio University Hospital Research Foundation and the Vappu Uuspää Foundation.
Kuopio, April 2018 Antti Jaroma
LIST OF THE ORIGINAL PUBLICATIONS
This dissertation is based on the following original publications:
I. Jaroma A, Soininvaara T, Kröger H: Periprosthetic tibial bone mineral density changes after total knee arthroplasty.Acta Orthop. 2016 Jun;87(3):268-73. doi: 10.3109/17453674.2016.1173982. Epub 2016 Apr 27.
Erratum in: Acta Orthop. 2016 Aug;87(4):x
II. Jaroma AV, Soininvaara TA, Kröger H: Effect of one-year post- operative alendronate treatment on periprosthetic bone after total knee arthroplasty. A seven-year randomised controlled trial of 26 patients.
Bone Joint J. 2015 Mar;97-B(3):337-45
III. Jaroma AV, Soininvaara TA, Kröger H: Changes in bone mineral density of the proximal femur and contralateral knee after total knee arthroplasty: a 4-year follow-up of 38 patients. Submitted
IV. Jaroma A, Suomalainen JS, Niemitukia L, Soininvaara T, Salo J, Kröger H: Imaging of symptomatic total knee arthroplasty with cone beam computed tomography. Acta Radiol. 2018 Jan 1:284185118762247 [Epub ahead of print]
The publications were adapted with the permission of the copyright owners.
CONTENTS
ABSTRACT ... 9
TIIVISTELMÄ ... 11
ACKNOWLEDGEMENTS ... 13
1 INTRODUCTION ... 18
2 REVIEW OF THE LITERATURE ... 20
2.1 Knee osteoarthrosis and total knee arthroplasty (TKA) ...20
2.1.1 Biomechanics ...20
2.1.2 Development of osteoarthrosis and effect on bone mineral density 22 2.1.3 Total knee arthroplasty ...23
2.2 Bone mineral density measurement ...24
2.2.1 Dual energy X-ray absorptiometry (DXA) ...24
2.2.2 Bone mineral density changes after total knee arthroplasty ...24
2.3 Inhibitors of bone resorption – bisphosphonates ...27
2.4 Symptomatic total knee arthroplasty ...27
2.4.1 Reasons for revisions and unsatisfied patients ...27
2.4.2 Clinical evaluation ...28
2.4.3 Computed tomography (CT) ...29
3 AIMS OF THE STUDY ... 30
4 SUBJECTS AND METHODS ... 31
4.1 Subjects and study design ...31
4.2 Bone mineral density measurements ...36
4.3 Imaging of the symptomatic or failed total knee arthroplasty ...38
4.3.1 Cone Beam Computed Tomography (CBCT) ...38
4.3.2 Assessment of the scans ...39
4.4 Patient follow-up ...40
4.5 Statistical methods ...40
5 RESULTS ... 42
5.1 Medium-term periprosthetic tibial bone mineral changes after total knee arthroplasty (I) ...42
5.2 Medium-term effect of alendronate on periprosthetic bone mineral changes after total knee arthroplasty (II) ...47
5.3 Medium-term bone mineral density in the proximal femur and contralateral knee after unilateral total knee arthroplasty (III) ...49
5.4 Inter- and intraobserver reliability of Cone Beam Computed Tomography (CBCT) scan for symptomatic total knee arthroplasty (IV) ...51
6 DISCUSSION ... 52
6.1 The relevance of the study...52
6.2 The subjects ...53
6.3 Validity of the data ...54
LIST OF THE ORIGINAL PUBLICATIONS
This dissertation is based on the following original publications:
I. Jaroma A, Soininvaara T, Kröger H: Periprosthetic tibial bone mineral density changes after total knee arthroplasty.Acta Orthop. 2016 Jun;87(3):268-73. doi: 10.3109/17453674.2016.1173982. Epub 2016 Apr 27.
Erratum in: Acta Orthop. 2016 Aug;87(4):x
II. Jaroma AV, Soininvaara TA, Kröger H: Effect of one-year post- operative alendronate treatment on periprosthetic bone after total knee arthroplasty. A seven-year randomised controlled trial of 26 patients.
Bone Joint J. 2015 Mar;97-B(3):337-45
III. Jaroma AV, Soininvaara TA, Kröger H: Changes in bone mineral density of the proximal femur and contralateral knee after total knee arthroplasty: a 4-year follow-up of 38 patients. Submitted
IV. Jaroma A, Suomalainen JS, Niemitukia L, Soininvaara T, Salo J, Kröger H: Imaging of symptomatic total knee arthroplasty with cone beam computed tomography. Acta Radiol. 2018 Jan 1:284185118762247 [Epub ahead of print]
The publications were adapted with the permission of the copyright owners.
CONTENTS
ABSTRACT ... 9
TIIVISTELMÄ ... 11
ACKNOWLEDGEMENTS ... 13
1 INTRODUCTION ... 18
2 REVIEW OF THE LITERATURE ... 20
2.1 Knee osteoarthrosis and total knee arthroplasty (TKA) ...20
2.1.1 Biomechanics ...20
2.1.2 Development of osteoarthrosis and effect on bone mineral density 22 2.1.3 Total knee arthroplasty ...23
2.2 Bone mineral density measurement ...24
2.2.1 Dual energy X-ray absorptiometry (DXA) ...24
2.2.2 Bone mineral density changes after total knee arthroplasty ...24
2.3 Inhibitors of bone resorption – bisphosphonates ...27
2.4 Symptomatic total knee arthroplasty ...27
2.4.1 Reasons for revisions and unsatisfied patients ...27
2.4.2 Clinical evaluation ...28
2.4.3 Computed tomography (CT) ...29
3 AIMS OF THE STUDY ... 30
4 SUBJECTS AND METHODS ... 31
4.1 Subjects and study design ...31
4.2 Bone mineral density measurements ...36
4.3 Imaging of the symptomatic or failed total knee arthroplasty ...38
4.3.1 Cone Beam Computed Tomography (CBCT) ...38
4.3.2 Assessment of the scans ...39
4.4 Patient follow-up ...40
4.5 Statistical methods ...40
5 RESULTS ... 42
5.1 Medium-term periprosthetic tibial bone mineral changes after total knee arthroplasty (I) ...42
5.2 Medium-term effect of alendronate on periprosthetic bone mineral changes after total knee arthroplasty (II) ...47
5.3 Medium-term bone mineral density in the proximal femur and contralateral knee after unilateral total knee arthroplasty (III) ...49
5.4 Inter- and intraobserver reliability of Cone Beam Computed Tomography (CBCT) scan for symptomatic total knee arthroplasty (IV) ...51
6 DISCUSSION ... 52
6.1 The relevance of the study...52
6.2 The subjects ...53
6.3 Validity of the data ...54
6.4 Periprosthetic medium-term tibial bone mineral changes after total knee
arthroplasty: The effect of alignment ... 55
6.5 Effect of one-year post-operative alendronate treatment on the medium-term periprosthetic bone changes ... 58
6.6 Effect of total knee arthroplasty on hips and contralateral knee joints ... 60
6.7 Cone beam computed tomography scan for symptomatic total knee arthroplasty ... 61
6.8 Implications for the future research ... 63
7 SUMMARY AND CONCLUSIONS ... 65
8 REFERENCES ... 66 ORIGINAL PUBLICATIONS
ABBREVIATIONS
AGC Anatomical Graduated Component
AKS American Knee Society
AMK Anatomic Modular Knee
AORI Anderson Orthopaedic Institute
AP Anteroposterior BMD Bone mineral density BMI Body Mass Index BMU Basic Multicellular
Unit
Ca Calcium
CBCT Cone Beam Computed Tomography
CT Computed
Tomography CV Coefficient of
Variation DXA Dual X-ray
Absorptiometry FAR Finnish Arthroplasty
Register
G.C. Geometric Center ICC Intraclass Coefficient
Correlation KUH Kuopio
University Hospital MPR Multiplanar
Reconstruction MSCT Multi-Slice Computed
Tomography OA Osteoarthrosis OARSI Osteoarthritis
Research Society International PE Polyethylene PROM Patient Reported
Outcome Measures PSI Patient Specific
Instrumentation RSA Radiostereometric
Analysis
ROI Region of Interest SD Standard Deviation THA Total Hip Arthroplasty TKA Total Knee
Arthroplasty
6.4 Periprosthetic medium-term tibial bone mineral changes after total knee
arthroplasty: The effect of alignment ... 55
6.5 Effect of one-year post-operative alendronate treatment on the medium-term periprosthetic bone changes ... 58
6.6 Effect of total knee arthroplasty on hips and contralateral knee joints ... 60
6.7 Cone beam computed tomography scan for symptomatic total knee arthroplasty ... 61
6.8 Implications for the future research ... 63
7 SUMMARY AND CONCLUSIONS ... 65
8 REFERENCES ... 66 ORIGINAL PUBLICATIONS
ABBREVIATIONS
AGC Anatomical Graduated Component
AKS American Knee Society
AMK Anatomic Modular Knee
AORI Anderson Orthopaedic Institute
AP Anteroposterior BMD Bone mineral density BMI Body Mass Index BMU Basic Multicellular
Unit
Ca Calcium
CBCT Cone Beam Computed Tomography
CT Computed
Tomography CV Coefficient of
Variation DXA Dual X-ray
Absorptiometry FAR Finnish Arthroplasty
Register
G.C. Geometric Center ICC Intraclass Coefficient
Correlation KUH Kuopio
University Hospital MPR Multiplanar
Reconstruction MSCT Multi-Slice Computed
Tomography OA Osteoarthrosis OARSI Osteoarthritis
Research Society International PE Polyethylene PROM Patient Reported
Outcome Measures PSI Patient Specific
Instrumentation RSA Radiostereometric
Analysis
ROI Region of Interest SD Standard Deviation THA Total Hip Arthroplasty TKA Total Knee
Arthroplasty
1 INTRODUCTION
Total Knee Arthroplasty (TKA) provides pain relief and improves function in pa- tients with knee osteoarthrosis (OA) (Skou, et al. 2015). It is also considered to be a cost-effective treatment with excellent long-term survival up to 96% after 15 years (Robertsson, et al. 2000, Dakin, et al. 2012). The durability of the prosthesis implants allows the aging and remodeling processes of the periprosthetic bone to take place.
The bone mineral loss induced by the implants may also interfere with the success of the arthroplasty (Karbowski, et al. 1999, Sundfeldt, et al. 2006). Because the num- ber of primary TKA procedures conducted worldwide is increasing (Niemelainen, et al. 2017, Inacio, et al. 2017), it becomes more important to understand the long- term changes of the periprosthetic bone. Plain knee radiographs are still a standard method in postoperative follow-up imaging of TKA. The alignment of the lower limb and prosthesis implant positioning as well as bone-to-cement interface can be quite well assessed. However, the quality of the periprosthetic bone may not be well defined by radiographs only (Ardran. 1951). The decrease of bone mineral density (BMD) after TKA operation is a well-defined phenomenon, that has been reported in several previous studies (Liu, et al. 1995, Petersen, et al. 1995, van Loon, et al. 2001, Soininvaara, et al. 2004a, Soininvaara, et al. 2004b). It is mainly caused by a stress-shielding phenomenon which unloads periprosthetic bone (Au, et al. 2007).
There are also contributions from impaired mobility postoperatively and local tis- sue reactions to the trauma caused by the operation itself. BMD is believed to reflect the quality of the bone rather well. Poor bone quality may lead to early migration of the prosthetic implants, periprosthetic fractures and perhaps also aseptic loosening, although this has not been convincingly proven in published studies (Tagil, et al.
2003).
Dual-energy X-ray absorptiometry (DXA) can be used for measuring peripros- thetic BMD with minimal precision error and good reproducibility (Trevisan, et al.
1998, Soininvaara, et al. 2000). It allows us to detect periprosthetic bone mineral loss and thus may give us a better understanding of the long-term changes after implan- tation of the prosthesis. DXA also gives us an opportunity to examine BMD changes of the neighboring joints after TKA (hips and contralateral knee) (Soininvaara, et al.
2004c, Kim, et al. 2014). With this method, we can also monitor the effect of bone active drugs on periprosthetic bone tissue.
The reasons behind symptomatic TKA are not always clear. The assessment of component rotations can be difficult with plain radiographs and it usually requires a computed tomography (CT) scan, scatter reduction software and correct under- standing of the reference axes (Victor. 2009). The cone-beam computed tomography (CBCT) technique is widely used in periodontology, and a method of choice in den- tal implant imaging (Tyndall, et al. 2012, Aljehani. 2014). The development of dedi-
cated CBCT imaging systems for musculoskeletal extremities have opened new indications for the use of the equipment (Zbijewski, et al. 2011).
The incidence of total knee arthroplasty operations is increasing and the proportion of patients with prosthesis implants is growing as the life expectancy of the population is increasing. The number of revision procedures and the financial burden of these complex surgical procedures are expected to also increase (Lavernia, et al. 2006, Barnett and Toms. 2012). Understanding of implant related changes in periprosthetic bone is important, since the clinical survival might also be associated with the quality of the bone environment (Levitz, et al. 1995, Trevisan, et al. 1998). The main purpose of this study was to quantify the medium- to long-term changes of periprosthetic bones and neighboring joints after TKA. Periprosthetic bone and components were also assessed by CBCT in patients with symptomatic TKA to validate the technique.
1 INTRODUCTION
Total Knee Arthroplasty (TKA) provides pain relief and improves function in pa- tients with knee osteoarthrosis (OA) (Skou, et al. 2015). It is also considered to be a cost-effective treatment with excellent long-term survival up to 96% after 15 years (Robertsson, et al. 2000, Dakin, et al. 2012). The durability of the prosthesis implants allows the aging and remodeling processes of the periprosthetic bone to take place.
The bone mineral loss induced by the implants may also interfere with the success of the arthroplasty (Karbowski, et al. 1999, Sundfeldt, et al. 2006). Because the num- ber of primary TKA procedures conducted worldwide is increasing (Niemelainen, et al. 2017, Inacio, et al. 2017), it becomes more important to understand the long- term changes of the periprosthetic bone. Plain knee radiographs are still a standard method in postoperative follow-up imaging of TKA. The alignment of the lower limb and prosthesis implant positioning as well as bone-to-cement interface can be quite well assessed. However, the quality of the periprosthetic bone may not be well defined by radiographs only (Ardran. 1951). The decrease of bone mineral density (BMD) after TKA operation is a well-defined phenomenon, that has been reported in several previous studies (Liu, et al. 1995, Petersen, et al. 1995, van Loon, et al. 2001, Soininvaara, et al. 2004a, Soininvaara, et al. 2004b). It is mainly caused by a stress-shielding phenomenon which unloads periprosthetic bone (Au, et al. 2007).
There are also contributions from impaired mobility postoperatively and local tis- sue reactions to the trauma caused by the operation itself. BMD is believed to reflect the quality of the bone rather well. Poor bone quality may lead to early migration of the prosthetic implants, periprosthetic fractures and perhaps also aseptic loosening, although this has not been convincingly proven in published studies (Tagil, et al.
2003).
Dual-energy X-ray absorptiometry (DXA) can be used for measuring peripros- thetic BMD with minimal precision error and good reproducibility (Trevisan, et al.
1998, Soininvaara, et al. 2000). It allows us to detect periprosthetic bone mineral loss and thus may give us a better understanding of the long-term changes after implan- tation of the prosthesis. DXA also gives us an opportunity to examine BMD changes of the neighboring joints after TKA (hips and contralateral knee) (Soininvaara, et al.
2004c, Kim, et al. 2014). With this method, we can also monitor the effect of bone active drugs on periprosthetic bone tissue.
The reasons behind symptomatic TKA are not always clear. The assessment of component rotations can be difficult with plain radiographs and it usually requires a computed tomography (CT) scan, scatter reduction software and correct under- standing of the reference axes (Victor. 2009). The cone-beam computed tomography (CBCT) technique is widely used in periodontology, and a method of choice in den- tal implant imaging (Tyndall, et al. 2012, Aljehani. 2014). The development of dedi-
cated CBCT imaging systems for musculoskeletal extremities have opened new indications for the use of the equipment (Zbijewski, et al. 2011).
The incidence of total knee arthroplasty operations is increasing and the proportion of patients with prosthesis implants is growing as the life expectancy of the population is increasing. The number of revision procedures and the financial burden of these complex surgical procedures are expected to also increase (Lavernia, et al. 2006, Barnett and Toms. 2012). Understanding of implant related changes in periprosthetic bone is important, since the clinical survival might also be associated with the quality of the bone environment (Levitz, et al. 1995, Trevisan, et al. 1998). The main purpose of this study was to quantify the medium- to long-term changes of periprosthetic bones and neighboring joints after TKA. Periprosthetic bone and components were also assessed by CBCT in patients with symptomatic TKA to validate the technique.
2 REVIEW OF THE LITERATURE
2.1 KNEE OSTEOARTHROSIS AND TOTAL KNEE ARTHRO- PLASTY (TKA)
2.1.1 Biomechanics
The knee joint is located between femur and tibia, which are the two longest bones of the human skeleton. It is the largest weight-bearing joint in human body. There- fore, there are high mechanical forces transferred through the joint especially dur- ing walking, kneeling and climbing stairs. The patella is responsible in transmitting the tensile force of the extensor apparatus across the knee. Gait analysis has shown that in normally aligned knees during walking, approximately 70% of the total load is transmitted through the medial compartment (Hurwitz, et al. 1998), causing 2.5- fold load to the medial joint surface compared with the lateral one (Baliunas, et al.
2002). The forces from the femoral condyles to the tibial plateau during normal walking have been estimated to be 2-4 times the body weight. At 45 degrees of knee flexion, the tensile force in the surface of patella reaches the maximum, which can be 7-8 times the body weight during deep knee bends such as kneeling (Taylor, et al. 2004).
The lower limb mechanical axis is regarded as the most important biomechani- cal mechanism of the knee joint. The mechanical axis is a combination of the femo- ral and tibial axis. The femoral axis is measured from the center of the femoral head to the center of the knee joint. The tibial axis is measured from the center of the knee to the center of the ankle joint (or center of the talus). The angle between the femoral and tibial axis demonstrates the degree of the aberration from the straight mechanical axis. Varus alignment means that the mechanical axis deviates medially from the center of the knee and valgus alignment laterally, respectively (Figure 1).
A proper mechanical axis is considered to provide optimal and equal loading con- ditions of the tibial condyles (Hvid, et al. 1988, Miyazaki, et al. 2002). A major pur- pose of the joint replacement surgery is to restore a normal axis, and a postopera- tive aberration of 3 degrees to valgus or varus is still considered to be acceptable.
The varus malalignment caused by knee OA further increases the normally greater load of the medial tibial condyle. Valgus malalignment, on the other hand, dimin- ishes the load-bearing forces of the medial condyle and more weight is transferred through the lateral compartment of the joint. Force-analysis calculations and dy- namic analysis of forces around the knee during gait have also shown that the me- dial compartment bears the entire load in knees with varus malalignment, and that the lateral compartment bears increased load only in instances of more advanced valgus malalignment (Li and Nilsson. 2001). Deviation of alignment is also associat-
ed with the progression of knee OA (Sharma, et al. 2001, Felson, et al. 2005, Sharma.
2007, Eckstein, et al. 2009, Khamaisy, et al. 2015).
Figure 1. Varus alignment (A) and valgus alignment (B) of the knee.
(A) The lower limb mechanical axis is in 21 degrees of varus. (B) The lower limb mechanical axis
is in 10 degrees of valgus.
During the knee flexion, there is a complex pattern movement between the articular facets of the distal femur and proximal tibia. The medial condyle of the femur can be viewed as a sphere, which rotates to produce a combination of flexion, longitu- dinal rotation and minimal varus. There is only a minimal translation of approxi- mately ±1,5mm between the medial femoral condyle and medial tibial facet. On the lateral side, there is a rolling and sliding movement, which allows a 15mm posterior translation of the lateral femoral condyle. As a consequence, the tibia rotates inter- nally approximately 30 degrees between 10 and 120 degrees of flexion (Pinskerova, et al. 2000, Pinskerova, et al. 2003, Freeman and Pinskerova. 2003, Freeman and Pinskerova. 2005).
The geometry of the distal femur and proximal tibia are intimately linked with the kinematics of the tibiofemoral and patellofemoral joints. Therefore, it is necessary to define the anatomical landmarks, especially in TKA surgery, since any misplacement will affect the loads and ligament tensions, leading to aberrant kinematics of the prosthesis (Victor. 2009). The generalized use of CT has given possibilities to assess the rotational alignments (Berger, et al. 1993). The rotation of the femur is typically determined by the angle comparing the surgical epicondylar axis with the posterior condylar axis, which is a line connecting the surfaces of the
2 REVIEW OF THE LITERATURE
2.1 KNEE OSTEOARTHROSIS AND TOTAL KNEE ARTHRO- PLASTY (TKA)
2.1.1 Biomechanics
The knee joint is located between femur and tibia, which are the two longest bones of the human skeleton. It is the largest weight-bearing joint in human body. There- fore, there are high mechanical forces transferred through the joint especially dur- ing walking, kneeling and climbing stairs. The patella is responsible in transmitting the tensile force of the extensor apparatus across the knee. Gait analysis has shown that in normally aligned knees during walking, approximately 70% of the total load is transmitted through the medial compartment (Hurwitz, et al. 1998), causing 2.5- fold load to the medial joint surface compared with the lateral one (Baliunas, et al.
2002). The forces from the femoral condyles to the tibial plateau during normal walking have been estimated to be 2-4 times the body weight. At 45 degrees of knee flexion, the tensile force in the surface of patella reaches the maximum, which can be 7-8 times the body weight during deep knee bends such as kneeling (Taylor, et al. 2004).
The lower limb mechanical axis is regarded as the most important biomechani- cal mechanism of the knee joint. The mechanical axis is a combination of the femo- ral and tibial axis. The femoral axis is measured from the center of the femoral head to the center of the knee joint. The tibial axis is measured from the center of the knee to the center of the ankle joint (or center of the talus). The angle between the femoral and tibial axis demonstrates the degree of the aberration from the straight mechanical axis. Varus alignment means that the mechanical axis deviates medially from the center of the knee and valgus alignment laterally, respectively (Figure 1).
A proper mechanical axis is considered to provide optimal and equal loading con- ditions of the tibial condyles (Hvid, et al. 1988, Miyazaki, et al. 2002). A major pur- pose of the joint replacement surgery is to restore a normal axis, and a postopera- tive aberration of 3 degrees to valgus or varus is still considered to be acceptable.
The varus malalignment caused by knee OA further increases the normally greater load of the medial tibial condyle. Valgus malalignment, on the other hand, dimin- ishes the load-bearing forces of the medial condyle and more weight is transferred through the lateral compartment of the joint. Force-analysis calculations and dy- namic analysis of forces around the knee during gait have also shown that the me- dial compartment bears the entire load in knees with varus malalignment, and that the lateral compartment bears increased load only in instances of more advanced valgus malalignment (Li and Nilsson. 2001). Deviation of alignment is also associat-
ed with the progression of knee OA (Sharma, et al. 2001, Felson, et al. 2005, Sharma.
2007, Eckstein, et al. 2009, Khamaisy, et al. 2015).
Figure 1. Varus alignment (A) and valgus alignment (B) of the knee.
(A) The lower limb mechanical axis is in 21 degrees of varus.
(B) The lower limb mechanical axis is in 10 degrees of valgus.
During the knee flexion, there is a complex pattern movement between the articular facets of the distal femur and proximal tibia. The medial condyle of the femur can be viewed as a sphere, which rotates to produce a combination of flexion, longitu- dinal rotation and minimal varus. There is only a minimal translation of approxi- mately ±1,5mm between the medial femoral condyle and medial tibial facet. On the lateral side, there is a rolling and sliding movement, which allows a 15mm posterior translation of the lateral femoral condyle. As a consequence, the tibia rotates inter- nally approximately 30 degrees between 10 and 120 degrees of flexion (Pinskerova, et al. 2000, Pinskerova, et al. 2003, Freeman and Pinskerova. 2003, Freeman and Pinskerova. 2005).
The geometry of the distal femur and proximal tibia are intimately linked with the kinematics of the tibiofemoral and patellofemoral joints. Therefore, it is necessary to define the anatomical landmarks, especially in TKA surgery, since any misplacement will affect the loads and ligament tensions, leading to aberrant kinematics of the prosthesis (Victor. 2009). The generalized use of CT has given possibilities to assess the rotational alignments (Berger, et al. 1993). The rotation of the femur is typically determined by the angle comparing the surgical epicondylar axis with the posterior condylar axis, which is a line connecting the surfaces of the
