Kienböck disease is a condition that typically occurs in the "at-risk" patient, in the "atrisk" aspect of the proximal condyle of the "at-risk" lunate. In the active male, repetitive loading causes the stress fracture that commences in the single layer proximal subchondral bone plate. The lunate fracture commences at the point the lunate cantilevers over the edge of the distal radius, and then takes on the shape of the radius. We postulate that the stress fracture violates the parallel veins of the venous subarticular plexus-leading to localized venous hypertension and subsequent ischemia and edema of the fatty marrow. The increased osseous compartment pressure further potentiates the venous obstruction, producing avascular necrosis. If the fracture remains localized, it can heal or settle into a stable configuration, so that the wrist remains functional. Fractures of the subchondral bone plate produce irregularity of the lunate articular surfaces and secondary "kissing lesions" of the lunate facet and capitate, and subsequent degeneration. The lunate collapses when the fracture is comminuted, or there is disruption of the spanning trabeculae or a coronal fracture. The secondary effect of the lunate collapse is proximal migration of the capitate between the volar and dorsal fragments, producing collapse of the entire central column. The proximal carpal row is now unstable, and is similar to scapholunate instability, where the capitate migrates between the scaphoid and lunate. The scaphoid is forced into flexion by the trapezium, however, degeneration of the scaphoid and scaphoid facet only occurs in late disease or following failed surgery. In Kienböck disease, the secondary effects of the collapsing lunate are a "compromised" wrist, including: deformity and collapse of the central column, degeneration of the central column (perilunate) articulations, proximal row instability (i.e., between the central and radial columns), and degeneration of the radial column.

Few options exist for the resurfacing of web-space and small soft tissue defects of the dorsum of the distal foot. The study examines the anatomy of the second to fourth dorsal metatarsal arteries in 16 fresh frozen cadavers to determine if the anatomy correlates to that in the hand, permitting the design of local flaps based on perforators of these vessels. A clinical case is also presented, illustrating the efficacy of such a perforator-based flap.Sixteen Asian cadaveric lower limbs were used for this study. The specimens were prepared with latex dye injection. Dissection under loupe magnification was carried out to determine the position and caliber of the cutaneous perforators from the dorsal metatarsal arteries, and the spread of the latex dye in the skin from these cutaneous perforators. One clinical case illustration of this perforator-based flap for distal foot defect resurfacing is presented.In our cadaveric study, each second to fourth dorsal metatarsal artery had between 2 and 5 cutaneous perforators with calibers of 0.5 to 0.7 mm in diameter. The most distal cutaneous perforator was present consistently, always arising between the heads of the respective metatarsals.In conclusion, the vascular anatomy of the second to fourth dorsal metatarsal arteries is similar to that in the hand, thus allowing for the design of reliable perforator-based flaps for distal foot resurfacing.

Kienböck disease is a disorder of impaired lunate vascularity which ultimately has the potential to lead to marked degeneration of the wrist and impaired wrist function. The aetiology of the avascular necrosis is uncertain, but theories relate to ulnar variance, variability in lunate vascularity and intraosseous pressures. Clinical symptoms can be subtle and variable, requiring a high index of suspicion for the diagnosis. The Lichtmann classification has historically been used to guide management. We present a review of Kienböck disease, with a focus on the recent advances in assessment and treatment. Based on our understanding thus far of the pathoanatomy of Kienböck's disease, we are proposing a pathological staging system founded on the vascularity, osseous and chondral health of the lunate. We also propose an articular-based approach to treatment, with an arthroscopic grading system to guide management.

Carpal tunnel syndrome is the most common nerve entrapment in the upper limb and carpal tunnel release (CTR) provides the most predictable outcome and relief of symptoms. Incomplete carpal tunnel releases are uncommon, however, in the event of incomplete surgical releases, symptoms following such incomplete releases tend to be more severe than the symptoms presented at the initial complaint. We present our experience in utilizing high definition ultrasound to reliably and accurately localize the anatomical cause to aid focused revision CTR.

The volar approach to the distal radius is an increasingly popular method of exposing fractures of the distal radius for purposes of reduction and internal fixation. We present five clinical cases and one cadaveric case of an incidental finding of an aberrant flexor of the forearm. A literature review undertaken showed few previous case reports of this relatively uncommon anatomic variant. The possibility of seeing the flexor carpi radialis brevis muscle during a volar approach to the distal radius should be made known to all orthopedic and hand surgeons.