Differentiation Between Pyogenic Flexor Tenosynovitis and Other Finger Infections.

BACKGROUND: Hospital transfer decisions regarding pyogenic flexor tenosynovitis (PFT) are made difficult by emergency department presentations similar to other finger infections, with pain, redness, and functional limitation. Our objectives were to: (1) determine diagnostic sensitivity and specificity of Kanavel signs; and (2) identify existing factors most predictive of PFT during initial presentation. METHODS: Adult patients who underwent surgical consultation for concern of PFT over a 5-year period were identified retrospectively. Bivariate screening identified clinical criteria for differentiation, and multivariate logistic regression was performed to control for confounding. We then created a prediction algorithm for diagnosis of PFT. Receiver operating characteristic (ROC) curve analysis was used to evaluate diagnostic accuracy. RESULTS: Patients with PFT differed significantly from those with non-PFT finger infections in regard to the 4 Kanavel signs, duration of symptoms less than 5 days, and erythrocyte sedimentation rate. Sensitivity of the Kanavel signs ranged from 91.4% to 97.1%. Specificity ranged from 51.3% to 69.2%. Logistic regression identified independent predictors for PFT as tenderness along the flexor tendon sheath, pain with passive extension, and duration of symptoms less than 5 days. A prediction algorithm incorporating these 3 factors showed an area under the ROC curve of 0.91 (95% confidence interval, 0.840-0.979). CONCLUSIONS: Kanavel signs have high sensitivity for detecting PFT but have poor specificity on an individual basis. Clinical prediction algorithms that combine the relevant factors may be helpful in the development of clinical prediction tools and educational materials for optimization of emergency hand care systems. Further prospective study is needed.

Prosthetic Design in Total Wrist Arthroplasty.

Total wrist arthroplasty (TWA) provides a motion-preserving alternative to total wrist arthrodesis for low-demand patients with debilitating pancarpal arthritis. The earlier generation total wrist implants had high complication and failure rates. Advances in prosthetic design have contributed to improved clinical outcomes and implant survivorship. The current fourth-generation implants allow for expansion of indications for TWA. Careful patient selection remains critical; patients with high-demand lifestyles and poor bone stock may not be candidates. Long-term studies on implant survival and patient outcomes are critical for the current generation total wrist implants in assessing their long-term value compared with total wrist arthrodesis.

Limited intercarpal fusion as a salvage procedure for advanced Kienbock disease.

BACKGROUND: With progressive lunate collapse, salvage procedures in advanced Kienbock disease attempt to provide pain relief and maintain motion. Scaphocapitate arthrodesis may provide a durable option with comparable outcomes to proximal row carpectomy in the well-selected patient. METHODS: We performed a retrospective chart review of all consecutive patients with Lichtman stage IIIA or IIIB Kienbock's disease who underwent either scaphocapitate or scaphotrapeziotrapezoid-capitate arthrodesis from January 2004 to December 2013. RESULTS: Twelve patients were included with a mean age of 41.6 years. Ten patients underwent scaphocapitate arthrodesis, while two patients underwent scaphotrapezio-trapezoid-capitate arthrodesis with an average clinical follow-up of 13.1 months. All patients achieved fusion. The average postoperative flexion-extension arc was 53° (range 20-110°). The average ulnar deviation was 9° (range 5-15°), and the average radial deviation was 13° (range 5-25°). Postoperative pain scores were significantly improved, having changed from an average of 6.6 preoperatively to 2.8 on a 10-point scale (W = 18, P < 0.05). CONCLUSIONS: Despite a mean flexion-extension arc that is reduced from that of a normal individual, the postoperative range of motion following a midcarpal arthrodesis was not significantly different than that reported in a recent systematic review of proximal row carpectomy (73.5° compared with 53°, respectively) (P = 0.05). Additionally, given the significant postoperative reduction in associated pain symptoms at the time of follow-up, scaphocapitate arthrodesis should be considered as a treatment option for wrist salvage in the patient with advanced Kienbock's disease.

Management of complications after rotator cuff surgery.

Rotator cuff repair (RCR) is a common procedure performed by orthopedic surgeons via arthroscopic, open, or mini-open techniques. While this surgery is considered to be of low morbidity, several potential complications can arise either intraoperatively or during the postoperative time period. Some of these complications are related to the surgical approach (arthroscopic or open), while others are patient dependent. Many of these complications can be managed through nonoperative means; however, early recognition and timely treatment is essential in limiting the long-term sequela and improving patient outcome. There are several different ways to classify complications after RCR repair: timing, severity, preventability, whether or not the pathology is intra- or extra-articular, and the type of treatment necessary. It is essential that the surgeon is cognizant of the etiology contributing to the failed RCR surgery in order to provide timely and proper management.

Methamphetamine enhances memory of operantly conditioned respiratory behavior in the snail Lymnaea stagnalis.

Amphetamines have been used as cognitive enhancers to promote learning and memory. Amphetamines are also drugs of abuse that may promote the initiation of strong memories that ultimately lead to addiction. To understand how methamphetamine (Meth) may be augmenting learning and memory, we chose a relatively simple system, the pond snail, Lymnaea stagnalis. We studied the effects of Meth exposure on the long-term memory (LTM), extinction and reinstatement of operantly conditioned aerial respiratory behavior in Lymnaea. We first determined doses of Meth that would acutely alter respiratory behavior. Next, we measured the impact of training snails in Meth solution or water (control group) using a training procedure that produces LTM (>6 h) in control conditions. Meth exposure impaired the expression of LTM 21 h after two training sessions, but this appeared to be a context-dependent effect only. However, snails exposed to 3.3 mumol l(-1) Meth during training had a decreased rate of extinction of the operantly conditioned memory. We then tested whether this decreased ability of snails to extinguish memory was due to enhanced LTM or impaired extinction of that memory. Snails were operantly conditioned in water and exposed to Meth 16 h after their last trial but 4-5 h prior to extinction. Meth produced an increase rather than a decrease in extinction rate. Thus, Meth impaired extinction only when snails were exposed to Meth during training. Last, we tested the effect of Meth on the ability to form LTM using a single training procedure that is suboptimal for LTM formation. Control snails did not demonstrate LTM, as expected, but pre-exposure of snails to 3.3 micromol l(-1) Meth 24 h prior to the single training session produced LTM 24 h later, indicating that Meth pre-exposure primed snails for LTM formation. Taken together, our studies suggest that LTM is strengthened by Meth such that extinction training is less effective. Lymnaea provides a simple and useful model system to dissect the cellular and/or molecular mechanisms of how Meth may initiate the formation of stronger memories.