Healing Processes of the Glenoid Labral Lesion in a Rabbit Model of Shoulder Dislocation

Abstract

Traumatic dislocation most commonly occurs at the shoulder joint. After an initial dislocation of the shoulder, the labrum is usually detached from the glenoid (Bankart lesion). If this lesion fails to heal, surgical repair is necessary. The purpose of this study was to determine the histological and biomechanical healing process of a simulated Bankart lesion created in rabbits. A labral injury was surgically created in 40 Japanese White rabbits. The labrum was sharply dissected from the glenoid rim simulating a Bankart lesion, and was repositioned without sutures. The joint capsule, the supraspinatus and infraspinatus tendons, and the deltoid were anatomically repaired with sutures. Eight rabbits each were sacrificed at 1, 2, 3, 4, and 5 weeks after the surgery for histological and biomechanical examinations (4 animals each). The histology and biomechanical properties of the normal capsulolabral structure was examined in 8 control rabbits. Inflammatory cell infiltration into the gap between the glenoid and the labrum was noted from 1 week. The gap was covered with fibrous connective tissue accompanied by the collagen fibers by 3 weeks. The healing process was completed histologically by 3 weeks. Biomechanically, the tensile load, which decreased significantly at 1 week, gradually increased and returned to the level of intact shoulder at 4 weeks. At least four weeks are necessary for the healing of the labral injury in rabbits. Considering the difference between humans and rabbits, it seems reasonable to let the patients go back to sports 2 to 3 months after dislocation or surgical repair.

Do nonsteroidal anti‐inflammatory drugs affect the outcome of arthroscopic Bankart repair?

“…The use of NSAIDs for the treatment of post‐operative pain is controversial for procedures involving healing between bone and tendon as it is shown that NSAIDs and COX2‐inhibitors affect the tendon‐to‐bone healing in experimental animal models (Cohen et al., ; Dimmen et al., ). Healing of labral lesions involve an inflammatory response (Abe et al., ) and could theoretically be inhibited by anti‐inflammatory drugs, but there are no published data that support the theory that treatment with short‐term NSAID in therapeutic doses has a negative effect on the outcome after arthroscopic shoulder surgery. It has been found in earlier clinical studies (Li et al., ) that any negative effect of NSAIDs on healing is dose‐dependent.…”

Allogenic Tendon-Autologous Cartilage Cells Transplantation Enhances Adhesive/Growth Ability and Promotes Chondrogenesis in a Rabbit Model of Glenoid Labrum Damage

“…In this study, the glenoid labrum lesions were prepared according to the method described in a previous study [11]. In brief, the rabbits were anaesthetized by intraperitoneal injection of 7% chloral hydrate, and the forelimb skins were preserved and sterilized with 75% alcohol.…”

Aktuelle Entwicklungen und Einsatzgebiete von Schulterorthesen

“…Abe et al konnten in einer an Mäusen durchgeführten biomechanischen Studie zeigen, dass das Labrum 4 Wochen nach Refixation eingeheilt ist [1]. Geht man von vergleichbaren Abläufen beim Menschen aus, ergibt sich nach ventraler oder dorsaler Schulterstabilisierung eine Immobilisationszeit von ca.…”