Statistical methods for detecting and comparing periodic data and their application to the nycthemeral rhythm of bodily harm: A population based study

Background  

Animals, including humans, exhibit a variety of biological rhythms. This article describes a method for the detection and simultaneous comparison of multiple nycthemeral rhythms.     

Penile and preputial tumours in the horse: literature review and proposal of a standardised approach

Penile and preputial tumours are not uncommon in the horse, but can cause discomfort and lead to serious complications. Several types of tumour of the male external genitalia have been described. The most common type is the squamous cell carcinoma (SCC), which is found mainly in older horses. Reports of a breed predilection for penile tumour formation are equivocal, but castration, coat colour, poor hygiene and various infectious agents have all been suggested to predispose to the development of some types of tumour (e.g. SCC, papilloma and melanoma). Careful assessment of the primary tumour is an important first step in the design of an optimal treatment protocol. Invasiveness, differentiation grade, tumour size and presence of metastases are all relevant to the decision to pursue additional diagnostic procedures or specific treatment options. To date, no standard protocol has been reported for the approach to penile tumours in the horse and treatments range from minimally invasive therapies (e.g. topical use of 5-fluorouracil) to radical surgical interventions (e.g. en bloc penile and preputial resection with penile retroversion). Completeness of removal of the neoplasm and therefore risk of recurrence is highly dependent on the type of therapy chosen. However, the size and histopathological features of the primary tumour are also important factors with respect to the likelihood of recurrence. This review describes the most common penile and preputial neoplasms in the horse, and outlines a standard protocol aimed at arriving at a specific diagnosis and tailoring the therapeutic approach accordingly.     

Laser Vaporization of the Dorsal Turbinate as an Alternative Method of Accessing and Evaluating the Paranasal Sinuses

Objective: To report a technique for stoma creation into the conchofrontal sinus (CFS) through the dorsal turbinate and to evaluate stoma as a site for sinoscopy. Study Design: Prospective experimental study. Animals: Cadaveric equine heads (n=2) and normal adult horses (5). Methods: Technique feasibility was established on 2 cadaver heads. A diode laser fiber with a contact probe was passed into the nasal passage through a custom built, laser introducer rod (LIR). A videoendoscope was passed ventral to the LIR. A site on the caudal, medial aspect of the turbinate overlying the dorsal conchal sinus (DCS) was identified. A stoma to facilitate endoscope passage was created through the turbinate and sinoscopy performed to identify structures within the CFS and caudal maxillary sinus (CMS) and to evaluate the quality of the approach. The procedure was then performed in standing, sedated horses. Time required, laser energy used and complications were recorded. Endoscopy was performed ≥5 weeks postoperatively to assess stoma size and long‐term effects of the procedure. Results: A stoma was successfully created through the turbinate in both cadaveric skulls and in 4 horses; the stoma persisted for ≥5 weeks. The location of the stoma in 1 horse precluded sinoscopy. Conclusions: Laser vaporization of the dorsal turbinate through the nasal passage creates a stoma that lasts for at least 5 weeks providing a portal to the paranasal sinuses. Based on experience in 1 horse stoma location is critical to ensure adequate endoscope manipulation and sinoscopy. Clinical Relevance: Standing endoscopic sinusotomy within the nasal cavity through the DCS is an alternative to more invasive sinusotomy techniques with fewer potential complications and a cosmetic result.     

In Vitro Mechanical Comparison of 2.0 and 2.4 Limited‐Contact Dynamic Compression Plates and 2.0 Dynamic Compression Plates of Different Thicknesses

Objective: To compare the bending structural stiffness and bending strength of thick and thin 2.4 mm limited contact dynamic compression plates (2.4 LC‐DCP), 2.0 mm LC‐DCP (2.0 LC‐DCP), and 2.0 dynamic compression plates (2.0 DCP). Study Design: In vitro mechanical study. Methods: Two thicknesses of 2.4 LC‐DCP, 2.0 LC‐DCP, and 2.0 DCP stainless‐steel plates were tested in 4‐point bending. Data were collected during bending until implants plastically deformed. Bending structural stiffness and bending strength were determined from load displacement curves. Mechanical properties were compared between plates and the effects of plate type, size, and thickness on stiffness and strength were assessed using ANOVA. Results: The thick 2.4 LC‐DCP implant was the stiffest and strongest; the thin 2.0 DCP implant was most compliant and weakest. Larger sized plates, thicker plates, and limited contact design of plates enhanced stiffness and strength. For the plates studied, plate size had a larger effect than plate type or thickness on stiffness and strength. Conclusion: Increasing the size (width) and thickness of plates increases both the bending structural stiffness and strength. For the plates studied, LC‐DCP implants were stiffer and stronger than DCP implants. Clinical Relevance: Plate bending structural stiffness and strength can be most effectively enhanced by using a larger sized plate, but gains can also be achieved by using a thicker plate and/or an LC‐DCP instead of a DCP implant when possible.     

Pararectal Cystotomy for Urolith Removal in Nine Horses

Objective: To report outcome of horses after standing pararectal cystotomy for removal of uroliths. Study Design: Case series. Animals: Horses (n=9) with cystic calculi. Methods: Medical records (December 1998–May 2007) of horses with cystic calculi that had standing pararectal cystotomy were reviewed. Signalment; urolith number, size, and type; surgical technique; sedation and analgesia protocols; intra‐ and postoperative complications and outcome were analyzed. Results: Uroliths (mean diameter, 6.37 cm; median, 6 cm; range, 3–10 cm) were removed intact without need for fragmentation. Eight (89%) horses had no complications and 1 horse (11%) developed persistent drainage from the perineal incision and incisional healing was prolonged. The complications resolved after wound revision, and although cystoscopy showed absence of uroliths, the clinical signs associated with cystitis recurred. Conclusions: Cystic calculi can be removed safely in standing horses using a pararectal approach. The procedure was well tolerated and no serious complications were encountered. Clinical Relevance: Pararectal cystotomy allows removal of cystic calculi in standing sedated horses. The technique may offer an economic advantage over approaches that require general anesthesia.     

Risk Factors for Femoral Fracture after Canine Press‐Fit Cementless Total Hip Arthroplasty

Objective: To evaluate risk factors for femoral fracture after porous‐coated cementless total hip arthroplasty (THA). Study Design: Case series. Animals: Dogs (n=74) that had cementless THA (n=84). Methods: Medical records of dogs from 2 referral hospitals were reviewed for occurrence of postoperative femoral fracture. Patient and operative (age, breed, sex, weight, and canal flare index [CFI], indication for arthroplasty, intraoperative fissure, cerclage usage, and implant sizes) factors were analyzed. Assessment of implant positioning and canal fill was performed on immediate postoperative radiographs. Femoral fractures (n=11) were evaluated and compared with 73 cases without fracture that met the inclusion criteria. Results: Mean (±SEM) age was 7.30±0.69 years for dogs with, and 4.77±0.37 years for dogs without femoral fracture. Age was positively associated with fracture (P=.022). Mean (±SEM) CFI was 1.80±0.09 for dogs with, and 1.98±0.04 for dogs without fracture. CFI was negatively associated with fracture (P=.045). Body weight, intraoperative fissure, cerclage use, implant size, position, and canal fill did not influence the occurrence of femoral fracture. Conclusions: Older dogs and dogs with lower CFI may be at increased risk for femoral fracture after porous‐coated cementless THA. Clinical Relevance: Risk factors exist for femoral fracture after cementless THA using porous‐coated implants, and should be critically evaluated during the patient selection. These risks should be weighed against the benefits of the system, and measures to minimize femoral fracture in at‐risk patients studied.