Ispitivanje biomehaničkih karakteristika modificiranih šavova fleksornih tetiva na animalnom modelu

doctoral thesis

• Title (english): Biomechanical trial of modified flexor tendon sutures - in vitro study
• Author: Zlatko Vlajčić; MBZ: 293823
• Mentor: Rado Žic (mentor)
• Committee member: nije dostupno (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; Zagreb
• Defense date and country: 2009-12-17, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences
• Universal decimal classification (UDC): 61 - Medical sciences

Abstract

Uvod
Intrasinovijalni šavovi fleksornih tetiva šake zbog povijesno gledano nezadovoljavajućih rezultata (zona «ničije zemlje»), spadaju u jedno od najispitivanijih područja kirurgije šake. Brojne su modifikacije i varijacije ovih šavova. U kliničkoj uporabi u RH još se uvijek uobičajeno koristi modificirani Kesslerov šav uz Kleinrt-ov protokol rane pasivne mobilizacije. Zahtjevi za ranom aktivnom mobilizacijom koja ima dokazane prednosti postavili su nove kriterije „idealnog šava“ poglavito glede tenzijske snage. Istražene su modifikacije i varijacije ovog šava koje bi mogle zadovoljiti nove kriterije.
Materijali i metode
U studiji su korištene 93 sviježe svinske nožice čuvane na –20°C i svaka je odmrznuta do sobne temperature neposredno prije odvajanja, presijecanja, postavljanja šava i testiranja dinamometrom na principu konstantne brzine istezanja. Ukupno su 93 tetive četvrtog dubokog ekstenzora zašivene pod lupom s uvećanjem od 3,5 podijeljene u tri osnovne skupine od po 10 uzoraka: modificirani Kesslerov šav, dvostruko modificirani Kesslerov šav i intaktne tetive kao kontrolna skupina, te sedam dodatnih skupina s 10-12 uzoraka i daljnjim varijacijama glede upredenog ili jednonitnog konca, mjesta i broja čvorova (međučvor, dva čvora i bočni čvor) i vrste perifernog šava (jednostavni obični ili ukriženi).
Rezultati
Ultimativna (maksimalna) tenzijska sila, maksimalno produljenje (istezanje), rad i vrijeme su pokazali statistički značajnu razliku među trima glavnim skupinama ali usporedba sedam dodatnih varijacija nije pokazala značajnu razliku u produljenju, radu i vremenu dok za ultimativnu silu jest.

Zaključak
Izabrana osnovna dvostruka modifikacija Kesslerovog (DMK) šava zahtijeva statistički značajno veću ultimativnu silu za popuštanje u odnosu na standardni modificirani Kesslerov šav. Inačica DMK šava s perifernim ukriženim šavom je najčvršći šav od svih ispitivanih inačica. Na osnovu raspona sile za pretpostaviti je kako bi se varijacijom šava s perifernim ukriženim šavom mogla postići rana aktivna mobilizacija što nije slučaj s običnim perifernim šavom. S obzirom na ultimativnu silu najslabija inačica jest ona s dva čvora između krajeva tetiva. Inačice s međučvorom, bočnim čvorom i jednonitnim koncem nisu pokazale statističku značajnu razliku u sili potrebnoj za popuštanje. Način popuštanja osnovne modifikacije DMK šava s upredenim ili jednonitnim koncem u smislu izvlačenja šava ili pucanja tetive i/ili šava podjednak je s obzirom na rabljeni konac.

Abstract (english)

Background
Intrasynovial flexor tendon repairs, because of historically unsatisfactory results (referred as “no man’s land”), belong to the most studied in hand surgery. There are numerous modifications and variations of those repairs. Clinicians’ preference in Croatia is still modified Kessler’s suture with early passive mobilization protocol referred as Kleinert’s protocol. Proven benefits of early active mobilization have inducted new criteria of “perfect suture” especially addressed to ultimate force. In this study we have examined different modifications and variations of modified Kessler’s suture, which could fulfill new criteria.
Methods
Ninety-three fresh pig trotters were stored at –20°C and each was thawed to room temperature just before tendons dissection, transsection, suture placement, and testing using dynamometer with constant rate of extension. The total of 93 extensor digiti quarti proprius tendons were repaired under 3.5 magnification and divided into three main groups of 10 specimens: modified Kessler suture, double modified Kessler suture and intact tendons as a control group, and seven additional groups of 10-12 specimens with further variations in type of thread (braided or monofilament), location and number of the knots (interlocked, doubled or out sided knot), and type of peripheral suture (simple "over and over" or cross-stitched).
Results
The ultimate (maximum) force, maximum elongation, work and time have pointed out significant difference among three main groups but comparation of the seven additional variations did not vary significantly in elongation, work and time except in ultimate force.

Conclusions
The ultimate force for the chosen basic modification of the double modified Kessler (DMK) was significantly higher then standard modified Kessler. The version of DMK with crossed peripheral suture was the strongest one among all tested variations. This version presumable could achieve, concerning range of force, early active mobilization opposite of the simple “over and over” peripheral stitch. The lowest strength manifested variations with two knots between tendon ends. The variation with interlocked and out sided knots or monofilament tread were not statistically significant regarding ultimate force. The frequency of suture failure of basic modification of DMK (suture pull out or tendon and/or suture rupture) was equal respecting braided or monofilament thread.

• Keywords: medicina
• Keywords (english): medicine
• Language: croatian
• URN:NBN: urn:nbn:hr:105:220200
• Study programme: Title: Biomedicine and Health Sciences; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje biomedicine i zdravstva (doktor/doktorica znanosti, područje biomedicine i zdravstva)
• Type of resource: Text
• Extent: 77 str.
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-05-05 06:52:11