Bone regeneration: current concepts and future directions

Bone regeneration is a complex, well-orchestrated physiological process of bone formation, which can be seen during normal fracture healing, and is involved in continuous remodelling throughout adult life. However, there are complex clinical conditions in which bone regeneration is required in large quantity, such as for skeletal reconstruction of large bone defects created by trauma, infection, tumour resection and skeletal abnormalities, or cases in which the regenerative process is compromised, including avascular necrosis, atrophic non-unions and osteoporosis. Currently, there is a plethora of different strategies to augment the impaired or 'insufficient' bone-regeneration process, including the 'gold standard' autologous bone graft, free fibula vascularised graft, allograft implantation, and use of growth factors, osteoconductive scaffolds, osteoprogenitor cells and distraction osteogenesis. Improved 'local' strategies in terms of tissue engineering and gene therapy, or even 'systemic' enhancement of bone repair, are under intense investigation, in an effort to overcome the limitations of the current methods, to produce bone-graft substitutes with biomechanical properties that are as identical to normal bone as possible, to accelerate the overall regeneration process, or even to address systemic conditions, such as skeletal disorders and osteoporosis

Missed obturator hip dislocation in a 19-year-old man.

Traumatic obturator hip dislocations are rare injuries that are typically diagnosed and managed acutely. We encountered a patient who presented with a painful hip 2 months after sustaining an undiagnosed traumatic obturator hip dislocation. After failed closed treatment, the hip was reduced with open reduction, utilizing a Kocher approach and a trochanteric osteotomy. At 15 months postoperatively, the patient maintained a functional range of motion without clinical or radiographic signs of posttraumatic arthritis or avascular necrosis

Distal humerus hemiarthroplasty: surgical technique

Distal humerus hemiarthroplasty (DHH) is a recent therapeutic option for the treatment of some acute unreconstructable humeral fractures, for the salvage of sequelae related to non-operative management or failed internal humeral fixation as well as in other rare pathological conditions. Standard anterior-posterior and lateral view X-rays and a CT scans are mandatory for an adequate preoperative planning. The main osseous and soft tissue stabilizers of the elbow should be intact or at least reparable because elbow stability is mandatory to be able to perform a DHH; in addition, both the medial and lateral columns should be either intact or reconstructable to guarantee an adequate soft tissue reinsertion and healing. This chapter aims to describe in detail the surgical technique of DHH. In particular the choice of the articular spool size, the orientation of the flexion-extension axis, and the reconstruction of soft tissue stabilizers represent the main key points for an optimal implantation