Although the etiology of osteoarthritis of the thumb carpometacarpal (CMC) joint remains unclear, some theories have focused on variations in the local anatomy of the abductor pollicis longus tendon insertion. This cadaver study of 68 specimens analyzed the relationship between a thenar insertion of an accessory abductor pollicis longus tendon and the presence and severity of thumb CMC osteoart...

The design of exoskeletons is a popular and promising area of research both for restoring lost function and rehabilitation, and for augmentation in military and industrial applications. A major practical challenge to the comfort and usability for exoskeletons is the need to avoid misalignment of the exoskeletal joint with the underlying human joint. Alignment mismatches are difficult to prevent...

Computer-aided technology can decrease the difficulty associated with arthroscopic surgery. Unlike a larger incision that exposes the whole joint, a small arthroscopic incision limits the surgeon to view the joint only from the arthroscope. Our computer-aided system for hip arthroscopy addresses this loss of joint visibility by (1) tracking tool position with a linkage of encoders, and (2) indi...

Traumatic trapeziometacarpal joint dislocation of the thumb accounts for less than 1% of all hand injuries. This injury is even less common in children. Optimal treatment strategies for this injury are still the subject of debate for both children and adults. We report a case of recurrent posttraumatic trapeziometacarpal joint dislocation in an eight-year-old girl. We believe our case is the fi...

BACKGROUND Identification of fluid in the elbow joint by physical examination alone can be challenging. Ultrasound can assist in the diagnosis of elbow effusion, and guide aspiration of the effusion. OBJECTIVES We illustrate the anatomy and ultrasound guidance technique of a posterior approach to elbow arthrocentesis using examples of normal and pathologic elbow joint ultrasound images. DIS...

AC (acromioclavicular) joint dislocations are a common injury seen by physicians. Symptoms range from minor discomfort with activity to complete disability of the extremity. Although most orthopaedic surgeons agree on how to treat either mild (type 1-2) or severe (type 4-6) injuries, there is no consensus for treatment of type 3 injuries. This article reviews the relevant literature pertaining ...

The functional anatomy of the distal radioulnar joint was studied in relation to the whole forearm, using three fresh-frozen, above-elbow amputation specimens. The specimens demonstrate how the proximal and distal radioulnar joints together form a bicondylar joint of special character. The proximal "condyle," the radial head, rotates axially, whereas the distal "condyle," the ulnar head, is fix...

The techniques of craniovertebral region stabilization introduced and used by the senior author over the last 20 years are summarized. The lateral masses of atlas and axis are strong and largely cancellous in nature and can be used for direct implantation of screws. Opening up of the joint and placement of bone graft within the joint stabilizes the region and provides a large area for bone fusi...