Cyclic testing of six-strand suture techniques for zone 2 flexor tendon lacerations.

Background: Biomechanical analysis using cyclic testing for repaired flexor tendons is a clinically relevant method. The aim of this study was to evaluate the tensile properties of two six-strand suture techniques, the triple looped suture and Yoshizu #1 suture techniques using cyclic testing under simulating early active mobilization conditions.

Methods: Twenty-five flexor digitorum profundus tendons harvested from fresh frozen human cadaver hands were repaired in zone 2 utilizing one of three repair techniques: the 2-strand modified Kessler (MK) technique as a control, the triple looped suture (TLS) and Yoshizu #1 suture (Y1) techniques.

Diminished cartilage creep properties and increased trabecular bone density following a single, sub-fracture impact of the rabbit femoral condyle.

Traumatic injury to articular cartilage can lead to post-traumatic arthritis. We used a custom pendulum device to deliver a single, near-fracture impact to the medial femoral condyles of rabbits. Impact was localized to a region ∼3 mm in diameter, and impact stress averaged ∼100 MPa.

Single high-energy impact load causes posttraumatic OA in young rabbits via a decrease in cellular metabolism.

Articular cartilage deterioration commonly occurs following traumatic joint injury. Patients with posttraumatic osteoarthritis (PTA) experience pain and stiffness in the involved joint causing limited mobility and function. The mechanism by which PTA occurs has not been fully delineated.

Effect of suture material and bone quality on the mechanical properties of zone I flexor tendon-bone reattachment with bone anchors.

Purpose: To compare the initial biomechanical properties of zone I flexor tendon to bone repairs performed using pull-out and anchor techniques and to investigate the effect of bone quality and suture materials on the strength of anchor repairs.

Methods: Using computed tomography, we measured bone mineral density and cortical thickness of the distal phalanx of 60 cadaver fingers (mean age, 77 years). Flexor digitorum profundus tendons were then transected at their insertion sites and repaired using a 4-strand grasping suture and either pull-out or anchor fixation.

PDGF-BB released in tendon repair using a novel delivery system promotes cell proliferation and collagen remodeling.

The purpose of this study was to promote fibroblast proliferation and collagen remodeling in flexor tendon repair through sustained delivery of platelet derived growth factor (PDGF-BB). The release kinetics of PDGF-BB from a novel fibrin matrix delivery system was initially evaluated in vitro. After the in vivo degradation rate of the fibrin matrix was determined using fluorescently tagged fibrin, PDGF-BB was delivered to the site of flexor tendon repair in vivo in a canine model.

Alendronate prevents bone loss and improves tendon-to-bone repair strength in a canine model.

Previously we showed a loss of bone and a concomitant decrease in mechanical properties in the first 21 days after flexor tendon insertion site injury and repair in a canine model. The goal of this short-term study was to suppress bone loss after insertion site repair using alendronate in an attempt to prevent the reduction in biomechanical properties. Flexor tendons of the second and fifth digits of the right forelimbs of canines were injured and repaired.

Early healing of flexor tendon insertion site injuries: Tunnel repair is mechanically and histologically inferior to surface repair in a canine model.

Orthopedic injuries often require surgical reattachment of tendon to bone. Tendon ends can be sutured to bone by direct apposition to the bone surface or by placement within a bone tunnel. Our objective was to compare early healing of a traditional surface versus a novel tunnel method for repair of the flexor digitorum profundus (FDP) tendon insertion site in a canine model.