Bioresorbable scaffolds for anterior cruciate ligament reconstruction: do we need an off-the-shelf ACL substitute?

Currently available anterior cruciate ligament (ACL) graft sources, autograft and allograft, present potential problems that a natural biomaterial ACL graft might be able to solve. Earlier efforts in the development of synthetic ACL grafts were less than optimal, and those devices have largely been abandoned. We can learn from these past failures, and potentially develop a bioresorbable scaffold for ACL reconstruction, which will provide immediate stability, promote and direct tissue in growth, and degrade at an appropriate rate, without harmful wear debris.

Design and characterization of a scaffold for anterior cruciate ligament engineering.

Advances in biomedical engineering have led to an understanding of the human body's capacity for anterior cruciate ligament (ACL) healing if provided the correct impetus--a long-term bioresorbable scaffold that anticipates the defect site's requirements. Tissue engineering an ACL requires a scaffold that can meet multiple and often conflicting mechanical and biological design requirements. The design and characterization of a hydrophilic silk scaffold is presented as an example of the preclinical testing required to fully characterize a scaffold for ACL reconstruction.

Bone graft substitutes in sports medicine.

Bone graft substitutes are used commonly in orthopedic surgery as an alternative to autograft bone. Autograft bone has the advantages of being osteoconductive, osteoinductive, and osteogenic. However, the quantity of autograft bone available is limited in a given patient and the harvest of autograft bone has been associated with significant morbidity.

Characterization of transcript levels for matrix molecules and proteases in ruptured human anterior cruciate ligaments.

An improved understanding of cellular responses during normal anterior cruciate ligament (ACL) function or repair is essential for clinical assessments, understanding ligament biology, and the implementation of tissue engineering strategies. The present study utilized quantitative real-time RT-PCR combined with univariate and multivariate statistical analyses to establish a quantitative database of marker transcript expression that can provide a "blueprint" of ACL wound healing. Selected markers (collagen types I and III, biglycan, decorin, MMP-1, MMP-2, MMP-9, and TIMP-1) were assessed from 33 torn ACLs harvested during reconstructive surgery.

Matrix metalloproteinases and their clinical applications in orthopaedics.

Imbalance in the expression of matrix metalloproteinases and their inhibitors contribute considerably to abnormal connective tissue degradation prevalent in various orthopaedic joint diseases such as rheumatoid arthritis and osteoarthritis. Matrix metalloproteinase expression has been detected in ligament, tendon, and cartilage tissues in the joint. They are known to contribute to the development, remodeling, and maintenance of healthy tissue through their ability to cleave a wide range of extracellular matrix substrates.

Future direction of the treatment of ACL ruptures.

The future of treatment of the ACL rupture is changing as our understanding of the biology surrounding the ACL continues to increase. It is our expectation that clinically applicable treatments, including the repair of the ACL and the development of a biologically engineered ACL, will occur in the next decade.

Surgical treatment of redisplaced fractures of the distal radius in patients older than 60 years.

Twenty patients aged 60 years or older (average age, 68 y) presented to our institution with a distal radius fracture made complex by virtue of displacement after a closed reduction and cast or external fixation immobilization. Ten of the fractures were volarly angulated and 10 were dorsally angulated. Fifteen patients' hands had associated soft-tissue swelling.