– Discussion: – blood supply to skin around the knee is random (as opposed to axial) – there are multiple small overlapping vessels that are interrupted by multiple small incisions; – random supply is sustained by both intrinsic and extrinsic sources; – intrinsic contributors to … Read more
– Discussion: – see bone circulation: – blood supply to tibial shaft is dervied from nutrient artery & periosteal vessels; – nutrient artery: – arises from posterior tibial artery as it enters into the posterior tibial cortex, distal to the soleal line at the … Read more
– See: – adolescent blounts: – growth plate anatomy – Infantile Blounts Disease: (pathologic tibia vara) – differential diagnosis and examination (see genu varum) – most common form of disease; – growth disorder of medial portion of proximal tibial physis; – … Read more
– Discussion: – body of talus is furnished w/ blood vessels from inferior talar surface in sinus tarsi and from talar neck; – non displaced fractures of talar neck disrupt intraosseous branches of tarsal sinus and tarsal canal, but major vascular sling remains intact; – w/ displaced fractures of talar neck, branches from dorsalis pedis artery … Read more
– Discussion: – ratio between perpendicular distance from lower articular margin of patella to tibial plateau (A) and the length of articular surface of patella (B) (use lateral view w/ knee in at least 30 deg of flexion); – AB ratio in 171 normal knees was 0.80 w/ no gender diff; … Read more
– Discussion: – in those cases in which inadequate bone remains, salvage of ankle joint may be brought about by realignment of tibiotalar joint & fusion of subtalar joint or by tibiocalcaneal fusion w/ tricortical bone graft. – this fusion has been used to salvage cases of avascular collapse w/ degenerative … Read more
– Discussion: – problem with standard BKA, the stump is often bulky and there are delays with patellar tendon prosthesis; – when healed the scar crosses the prominent crest of the tibia, which is often the point that broke down with prosthetic use; – note that the BKA prosthesis … Read more
– See: Prosthetic Feet: – PTB sockets: – provide some weight bearing support in the area of patella tendon and medial tibial flare; – BKA Suspension: – important design considerations for both sockets include – support (pressure distribution) – control (based … Read more
– See: Biomechanics Menu: – Anatomy of the ACL: – Biomechanics: – ultimate tensile load: 2160 ± 157 N – stiffness: 242 ± 28 N/mm; – passive knee extension produces forces along ACL only during last 10 degrees of knee extension; – hyper-extension: … Read more
– See: Role of Knee Joint During Gait: – Discussion: – patella increases the mechanical advantage of extensor muscles by transmitting forces across knee at greater distance (moment) from axis of rotation; – increases functional lever arm of quads as well as changing direction of pull of quad mechanism; … Read more