Extended proximal trochleoplasty for the correction of bidirectional patellar luxation in seven Pomeranian dogs

Seven Pomeranians with bidirectional patellar luxation (BPL) were prospectively studied regarding aetiology and results of a new surgical technique. Radiographic evaluation of the ratio between patellar ligament length and patellar bone length revealed no differences between Pomeranians with bidirectional patellar luxation and healthy stifle joints. Functional rather than anatomic patella alta might be associated with bidirectional patellar luxation in Pomeranians. The surgical outcome of extended proximal trochleoplasty was good‐to‐excellent in 87·5% of the stifles and all dogs achieved functional recovery. There was only minimal radiographic progression of osteophyte formation at 48 weeks after surgery. To the authors’ knowledge, this is the first report on bidirectional patellar luxation in small breed dogs and its successful surgical treatment.     

Treatment of a congenital lateral patellar luxation by recession trochleoplasty in a donkey foal

The present report describes the surgical treatment of a congenital lateral patellar luxation in a 6-month-old female donkey foal. The foal was presented with a slight crouched position, muscle atrophy, moderate lameness, reluctance to flex the right hindlimb at a walk and slight effusion of the right stifle joint. The foal responded painfully to the stifle flexion test. Irreducible lateral luxation of the right patella was confirmed on physical examination and radiography. The animal was treated surgically by recession trochleoplasty and imbrication of the medial joint capsule. The animal gradually improved after surgery, and good clinical results were reported after 6 months post-operatively. In conclusion, congenital lateral luxation of the patella should be considered as a congenital cause of lameness in donkeys and surgical repair by recession trochleoplasty and medial imbrication of the joint capsule can be helpful to treat this problem.     

Surgical correction of congenital medial patellar luxation in a llama

Unilateral congenital medial patellar luxation in a young llama was corrected by medial joint capsule release, tibial crest transposition, trochleoplasty, and lateral joint capsule imbrication. The techniques used were the same as described in the dog. One year after surgery, the llama was not lame, but had a valgus deformity originating at the stifle, most likely caused by lateral femoral condyle hypoplasia.     

Comparison of trochlear block recession and trochlear wedge recession for canine patellar luxation using a cadaver model

OBJECTIVE: To compare trochlear block recession (TBR) to trochlear wedge recession (TWR) with regards to patellar depth (percentage of patellar volume under the trochlear ridges), patellar articular contact, percentage of recessed trochlear surface area, and resistance to patellar luxation. STUDY DESIGN: In vitro computed tomography (CT) and biomechanical evaluation using a cadaver model. SAMPLE POPULATION: Twelve normal, large-breed canine cadavers. METHODS: Bilateral pelvic limb specimens with intact stifle joints were mounted on a positioning device. The femoral trochlear ridges were reduced to provide a standard shallow trochlea. TBR or TWR was performed to a standard depth randomly on paired specimens. CT and biomechanical evaluations were performed pre- and postoperatively in both an extended (148 degrees ) and flexed (113 degrees ) stifle position. CT images were digitized and measurements made using an image-analysis software program. Biomechanical testing consisted of applying 40 degrees of internal tibial rotation and documenting patellar luxation. RESULTS: The change in trochlear depth (depth of recession) was not significantly different between groups. In the extended stifle position (patella in the proximal trochlea), patellar depth and patellar articular contact with the recessed trochlea were significantly greater after TBR compared with TWR. The percentage of recessed trochlear surface area was significantly greater after TBR compared with TWR. In the extended position, a smaller percentage of the patellae luxated within 40 degrees of internal tibial rotation after TBR compared with TWR. CONCLUSIONS: TBR increases proximal patellar depth, increases patellar articular contact with the recessed proximal trochlea, recesses a larger percentage of trochlear surface area, and results in a greater resistance to patellar luxation in an extended position as compared with TWR. CLINICAL RELEVANCE: TBR may help limit the development of stifle DJD in dogs treated for canine patellar luxation.     

Rush immunotherapy in an experimental model of feline allergic asthma

Specific allergen immunotherapy represents the only curative treatment of allergy. No studies have evaluated its efficacy in feline allergic asthma. We hypothesized that an abbreviated course of immunotherapy (rush immunotherapy, RIT) would blunt eosinophilic airways inflammation in experimental feline asthma induced with Bermuda grass allergen (BGA). The 6-month study included asthmatic-RIT treated cats; asthmatic-no RIT treated cats; and non-asthmatic cats. RIT involved increasing parenteral doses (20-200 microg) of BGA over 2 days. Numbers of eosinophils in bronchoalveolar lavage fluid (BALF), serum and BALF immunoglobulins, lymphocyte blastogenesis assays, and cytokines in blood and BALF were evaluated. BALF eosinophils decreased (P=0.048) only in asthmatic-RIT treated cats (baseline 1.1 x 10(6); Month 6, 2.4 x 10(5)). Serum BGA-specific IgG was higher (P<0.001) at all time points after baseline within the asthmatic-RIT group, and was higher (P<0.001) than asthmatic-no RIT cats at Months 1 and 3. No differences (P=0.133) in BGA-specific IgE levels over time were noted among asthmatic-RIT cats, but this group had lower IgE levels (P<0.001) levels than asthmatic no-RIT cats at Months 3 and 6. Differences in BGA-specific IgA levels over time and between the two groups did not reach the traditional level of significance. The mean BGA stimulation index in the asthmatic-RIT cats was biologically insignificant at 6 months, reflecting BGA-specific lymphocyte hypoproliferation. Preliminary results of cytokine profiles were not significantly different; however, BAL cytokine profiles favoring a Th2 response prior to RIT shifted to increased IFN-g and IL-10 thereafter. RIT dampens eosinophilic airways inflammation in cats with experimental asthma. The mechanism of RIT may involve changes in allergen-specific immunoglobulins, induction of hyporesponsive lymphocytes, or alteration of cytokine profiles.     

Toggle-pin technique for management of coxofemoral luxation in an alpaca

Objective: To report repair of a coxofemoral joint luxation in an Alpaca using a toggle‐pin technique. Study Design: Case report. Animals: An 11‐month intact male Alpaca with luxation of the right coxofemoral joint. Methods: The Alpaca was anesthetized and an open repair and reduction of the luxation was performed using a toggle‐pin technique. Results: The luxation was successfully reduced. An Ehmer sling was used for the initial 3 days after surgery and the Alpaca was discharged 7 days postoperatively without complications. Follow‐up examinations confirmed maintained reduction of the coxofemoral joint, as well as no evidence of lameness or muscle atrophy. Conclusions: Coxofemoral joint luxations in Alpacas can be successfully repaired using a toggle‐pin technique alone, without the need for other techniques such as capsular reconstruction or greater trochanter transposition. Use of an Ehmer sling for the immediate postoperative period provided additional protection to the repair and was tolerated well.     

Treatment of a coxofemoral luxation in a pony using a prosthetic capsule technique

Objective: To report open reduction and joint stabilization using a prosthetic capsule technique for treatment of a craniodorsal coxofemoral luxation in a lightweight pony. Study Design: Clinical report. Animals: Pony stallion (8 years old, 113 kg). Methods: A craniodorsal approach to the coxofemoral joint was performed under general anesthesia. After open reduction, a prosthetic capsule technique was used. Four 3.5 mm self‐tapping cortical anchor screws were implanted: 2 screws were inserted above the cranial aspect of the dorsal acetabular rim, and 2 screws were inserted into the femoral neck. Subsequently, a #5 USP ultra‐high molecular weight polyethylene suture was placed through these anchor screws in figure‐8 fashion to serve as a prosthetic capsule. Routine closure and a medial patellar desmotomy completed the surgical procedure. Postoperatively, the pony was cross tied for 4 weeks to prevent it from lying down. Results: Neither short‐term nor long‐term complications occurred and the pony was sound at the follow‐up examination performed 15 months postoperatively. Conclusions: A prosthetic capsule technique can be used successfully to stabilize the coxofemoral joint after open reduction of a craniodorsal luxation in a lightweight pony.     

Rotation of the femoral trochlea for treatment of medial patellar luxation in a dog

A crossbreed dog was presented with non-weight bearing on the right hindlimb and a semi-flexed stifle. Clinical examination and radiographic investigation showed a grade 3 medial patellar luxation, characterised by hypoplasia of the medial trochlear ridge. No other significant skeletal abnormalities were detected. A 180 degrees rotation of the femoral trochlea was the surgical technique chosen to treat the trochlear dysplasia, the aim being to move the normal lateral ridge to the medial side and thereby prevent patellar luxation. This technique was able to restore correct conformation of the femoral trochlea and preserve the integrity of the trochlear groove cartilage, thus potentially retarding the progression of degenerative joint disease. The dog recovered fully and postoperative radiographic examinations showed healing of the rotated trochlea with only mild signs of degenerative joint disease.     

Evaluation of Key's hypothesis in the feline tibia: an experimental model for augmented bone healing studies

Key's hypothesis states that a segmental long bone defect 1.5 times the diaphyseal diameter exceeds the regenerative capacity of bone in skeletally mature dogs and results in nonunion. This hypothesis was evaluated in 5 adult cats with rigidly fixated segmental tibial ostectomies ranging from 1.25 to 1.52 times the diaphyseal diameter. Clinical, radiographic, and histologic data were obtained over a 12-week period. Healing was classified as mature bony union, clinical union, delayed union, or nonunion. Absence of a consolidating callus and instability after removal of fixation devices was found for all cats at 12 weeks. Scant formation of new bone within the gap was histologically evident for only 1 cat. In the remaining 4 cats, fibrous tissue and striated muscle predominated within the gap, and independent healing of the proximal and distal cut ends of the bone were observed. The occurrence of 4 nonunions and 1 equivocally delayed union indicated that Key's hypothesis overestimates the regenerative capacity of bone in the cat. Failure of this experimental model to produce clinical union within 12 weeks demonstrated that this model is a valid method of investigating augmented bone healing techniques that promote union within this period in the cat.     

Treatment of medial patellar luxation by femoral closing wedge ostectomy using a distal femoral plate in four dogs

This case report describes the treatment of recurrent medial patellar luxation associated with varus deformity of the distal femur by distal femoral ostectomy stabilised using a distal femoral plate. Four dogs (five affected limbs) were included in the study. All cases had received previous surgery for medial patellar luxation but remained significantly lame. All were treated by femoral ostectomy to correct distal femoral varus deformity with application of a distal femoral bone plate. All cases improved following surgery. An excellent outcome was recorded in four of five cases. Lameness persisted in one case despite satisfactory patellar stability as a result of concurrent cranial cruciate ligament deficiency. One case suffered implant failure. Femoral ostectomy is an effective treatment for medial patellar luxation associated with femoral varus deformity. The distal femoral plate provides a convenient method by which to stabilise the ostectomy. Care should be exercised when the 2 mm distal femoral plate is applied.     

Development of correction formulas for canine and feline urine specific gravity measured using a Japanese refractometer

One of the most important functions of the kidney is to concentrate urine through the reabsorption of water. Urine specific gravity (USG) is used in routine tests of urine concentration and can be estimated using a refractometer. However, as the scale of Japanese refractometer is based on experimental data from healthy Japanese people, and human USG obtained by Japanese refractometers show higher values than that by refractometer produced in Europe or the U.S.A. The purpose of this study was to establish correction formulas for the USG of dogs and cats measured using Japanese refractometers. In this study, we found that Japanese refractometers overestimated USG in both dogs and cats. This study shows that the correlation formulas described in this study are useful for the accurate evaluation of USG.     

Surgical correction of a coxofemoral luxation in a European Honey buzzard (Pernis apivorus) by incorporating a toggle-pin technique: A case report

A 2-year-old female European Honey buzzard (Pernis apivorus) was diagnosed with a coxofemoral luxation (craniodorsal) of the right leg. Modified toggle pin technique was performed to replace the ruptured ligament of head of femur with an artificial ligament. An anchor was tied to a monofilament-type nonabsorbable suture and placed into the buzzard's acetabular hole through the drilled femoral canal. The buzzard gradually regained full activity by 13 weeks following surgery, displaying a slight lameness but otherwise a completely normal range of motion without relapse or complication. In this specific case, the procedure was uneventful and the buzzard recovered over several months without relapse or complications. Further clinical reports including a larger number of animals are needed in order to determine whether this technique is safe and which surgical technique is more effective in birds with coxofemoral luxation.     

Bowel welding technique in dogs and cats using a diode laser: an experimental study

A laser bowel welding technique for dogs and cats was developed. The bowel was pinched using a special clamp having an opening on the body developed for this experiment (LW clamp). Using the 2 different types of contact probe (blunt tip: Laser Bipolar Dissector (LBD); sharp tip: Super Scalpel Dissector (SSD)), the laser passed through the hole in the LW clamp to cut the bowels, while at the same time, sealing the cut portion. The results obtained in this study showed that the optimum laser output using LBD was 6-10 W in dog and cat ileum, and 8-10 W in dog and cat colon. Optimum laser output using SSD was 6-8 W in dog ileum, 8-10 W in dog colon, 10 W in cat ileum and 6-8 W in cat colon. No marked differences were observed between ileum and colon when using either LBD or SSD. At the same power, burst pressure tended to be slightly higher with LBD than with SSD, although there were not significant differences between them. Histologically, complete sealing of the welded site was seen. Welding and cutting of bowel in dogs and cats was thus confirmed to be possible using the LW clamp in combination with LBD or SSD probes under a diode laser output of approximately 8 W for 50-80 s (400-640 J/cm). Thus, we can expect that this method is applicable to clinical veterinary medicine.