In:
The American Journal of Sports Medicine, SAGE Publications, Vol. 46, No. 7 ( 2018-06), p. 1711-1719
Abstract:
Clinically, onto-surface repair is commonly used for rotator cuff tears. The retear rate after rotator cuff repair (RCR) is relatively high, with failure occurring mostly at the tendon-bone connection site. For anterior cruciate ligament (ACL) reconstruction, into-tunnel reconstruction is commonly employed. The retear rate after ACL reconstruction is relatively low, with retears seldom occurring at the tendon-bone interface. No study on into-tunnel RCR has been conducted. Hypothesis: Into-tunnel RCR could promote fibrocartilage regeneration at the tendon-bone interface and has biomechanical advantage over onto-surface repair in a rabbit rotator cuff tear model. Study Design: Controlled laboratory study. Methods: Thirty-six New Zealand White rabbits were used in this study. The supraspinatus tendons were cut from the footprint to create a rotator cuff tear on both shoulders. On one side, the supraspinatus was cut longitudinally into 2 halves, sutured, and pulled into 2 tunnels through the greater tuberosity (into-tunnel repair). On the other side, the tendon was reattached to the surface of the footprint with transosseous sutures (onto-surface repair). Twelve animals were sacrificed, of which 6 were used for a histological examination and the other 6 for biomechanical testing, at 4, 8, and 12 weeks, respectively. Results: The tendon-bone interface in the into-tunnel group showed a different healing pattern from that in the onto-surface group. In the former, most of the tendon tissue in the tunnel was replaced with newly generated fibrocartilage; the rest of the tendon fibers appeared in large bundles with direct connection to the bone. In the latter, fibrocartilage regeneration was seldom found at the tendon-bone interface; the tendon near the bone surface appeared as small fibrils. The biomechanical evaluation revealed a higher ultimate load ( P 〈 .001) and stiffness ( P 〈 .001) at the tendon-bone junction in the into-tunnel group than those in the onto-surface group at 12 weeks. Conclusion: In a rabbit rotator cuff tear model, into-tunnel RCR could result in a different tendon-bone healing pattern, with obvious fibrocartilage regeneration at the interface and higher tendon-bone healing strength than that in onto-surface repair. Clinical Relevance: New RCR patterns may be developed to improve the tendon-bone healing pattern and obtain better tendon-bone healing strength.
Type of Medium:
Online Resource
ISSN:
0363-5465
,
1552-3365
DOI:
10.1177/0363546518764685
Language:
English
Publisher:
SAGE Publications
Publication Date:
2018
detail.hit.zdb_id:
197482-8
detail.hit.zdb_id:
2063945-4
SSG:
31
Permalink