A novel approach for posterior acetabular fractures: Surgical technique.

This article describes a novel approach, the Direct Posterior Approach (DPA) for the treatment of posterior acetabular fractures (posterior column, posterior wall, or both posterior column and wall). This technique allows direct visualization of the entire posterior wall, part of the hip capsule and the posterior column between the space of the gluteus medius and the piriformis superiorly. The approach spares the division of short external rotators, abductors, and hip capsule, thus preventing iatrogenic damage to the medial femoral circumflex artery, sciatic nerve, and superior and inferior gluteal neurovascular bundles, as well as protecting the vascularity of the fracture fragments.

[Establishment of a rabbit model of lumbar intervertebral disc degeneration via the paraspinal approach].

Objective: To establish a rabbit model of intervertebral disc degeneration by puncturing the anulus fibrosus through an approach between the longissimus dorsi muscle and obliquus externus abdominis.

Methods: The L(4/5) and L(5/6) intervetebral discs of 6 New Zealand white rabbits were punctured by an 18-gauge pin in the anterolateral annular fibrosus through an approach between the longissimus dorsi muscle and the obliquus externus abdominis with the right transverse processes of L(5) and L(6) resected; the L(2/3) discs were used as the control without exposure or needle stab, and the L(3/4) discs were subjected to sham operation with the discs exposed but not punctured after resecting the right transverse process of L(4). X-ray and magnetic resonance imaging (MRI) were performed preoperatively and at the 4th week after puncture.

Metformin stimulates osteoprotegerin and reduces RANKL expression in osteoblasts and ovariectomized rats.

Anti-diabetic drug metformin has been shown to enhance osteoblasts differentiation and inhibit osteoclast differentiation in vitro and prevent bone loss in ovariectomized (OVX) rats. But the mechanisms through which metformin regulates osteoclastogensis are not known. Osteoprotegerin (OPG) and receptor activator of nuclear factor κB ligand (RANKL) are cytokines predominantly secreted by osteoblasts and play critical roles in the differentiation and function of osteoclasts.