We report a group of 14 patients with fracture dislocations of the proximal interphalangeal joint with fracture fragments of adequate size to allow reduction of the proximal interphalangeal joint and internal mini screw fixation of the bone fragment attached to the palmar plate to the base of the middle phalanx. Three years after surgery, (range 25-52 months) the average total active range of motion of the proximal interphalangeal joint was 100 degrees (range 65-115 degrees) for the acute group (operation within 14 days of injury, n=7) and 86 degrees (range 60-110 degrees) for the chronic group (operation on average 46 days after injury, range 21-120 days, n=7). Longer delay from injury was associated with a decreased total range of motion (P=0.028). Further subluxation occurred in three chronic group patients, one required further surgery. The key to successful treatment of this injury is the re-establishment of joint congruity and early mobilization. With appropriate patient selection, pain free, satisfactory range of motion can be achieved. There is a risk of persistent subluxation or dislocation, particularly if treatment is delayed.
Intraosseous ganglion cyst of the lunate is an uncommon lesion and cause of wrist pain. Histopathologically it is identical to the common dorsal wrist ganglion and treatment by arthrotomy, curettage of the ganglion and bone graft resulted in clinical improvement in nine patients, six of whom became symptom-free.
The cytokine leukemia inhibitory factor (LIF) favors the survival and growth of axons in vitro and in vivo. Fibronectin has been shown to enhance nerve regeneration when added in combination with various growth factors including LIF. The goal of this study was to evaluate the effect of LIF plus fibronectin on the regeneration of transected nerve and functional recovery of reinnervated skeletal muscle, in one experimental model of peripheral nerve repair, at two recovery times. The rat sciatic nerve was cut at mid-thigh level and a silicone cuff containing either saline (control), LIF, or LIF plus fibronectin (L+F) was used to bridge the proximal and distal nerve stumps leaving a 1 cm gap between them. Rats were then explored at 6 or 12 weeks following the initial surgery. Regenerating nerves were assessed by measuring the diameter of myelinated axons, conduction velocity, and number of myelinated fibers. Muscle reinnervation was assessed by measuring muscle mass, force of contraction, and histologically for changes in muscle fiber type (type I and type II). In this report we demonstrate that at 6 weeks there were significant increases in 1) nerve conduction velocity, 2) myelinated axon diameter, and 3) number of myelinated axons over that of control (saline-treated) animals. Both LIF groups demonstrated a shift in type II muscle fiber area compared to saline-treated controls, with the L+F group having a significant increase in muscle mass. At 12 weeks there was an improved recovery over and above that demonstrated at 6 weeks. Muscle mass was 65% and 42% greater than control for LIF and L+F, respectively. Force of contraction, conduction velocity, myelinated fiber number, and diameter were also significantly greater for both LIF- and L+F-treated rats than saline-treated rats. These results demonstrate that LIF significantly improves the regeneration of damaged peripheral nerves and the preservation of muscle viability, resulting in greatly enhanced recovery of skeletal muscle function.
).Modern imaging techniques have enabled accurate preoperative planning in plastic and reconstructive surgery, 1 with advances translated to superior clinical outcomes and reduced operative length. In perforator flap surgery for breast reconstruction, preoperative computed tomography angiography (CTA) reliably, maps the vascular supply enabling the selection of donor site, flap, and the perforator. However, the interpretation of CTA scan data displayed on a two-
AbstractBackground Over the last decade, image-guided production of three-dimensional (3D) haptic biomodels, or rapid prototyping (RP), has transformed the way surgeons conduct preoperative planning. In contrast to earlier RP techniques such as stereolithography, 3D printing has introduced fast, affordable office-based manufacturing. We introduce the concept of 4D printing for the first time by introducing time as the fourth dimension to 3D printing. Methods The bones of the thumb ray are 3D printed during various movements to demonstrate four-dimensional (4D) printing. Principles and validation studies are presented here. Results 4D computed tomography was performed using "single volume acquisition" technology to reduce the exposure to radiation. Three representative scans of each thumb movement (i.e., abduction, opposition, and key pinch) were selected and then models were fabricated using a 3D printer. For validation, the angle between the first and the second metacarpals from the 4D imaging data and the 4D-printed model was recorded and compared. Conclusion We demonstrate how 4D printing accurately depicts the transition in the position of metacarpals during thumb movement. With a fourth dimension of time, 4D printing delivers complex spatiotemporal anatomical details effortlessly and may substantially improve preoperative planning.
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