Surgical Repair of Psittacine Femorotibial Luxation: A Case Series.

Luxation of the psittacine femorotibial joint most commonly occurs following trauma or as a development abnormality. Historically, this injury is considered to have a poor prognosis in birds; however, surgical management may result in acceptable and functional outcomes. This case series describes the surgical techniques, complications, and outcomes of 7 cases of femorotibial luxation in psittacine birds. Of the 7 cases, 6 were chronic injuries. Surgical repair methods included conjoined intramedullary pinning, transarticular pinning with an external skeletal fixator (ESF), a combination of extracapsular stabilization and ESF, ESF alone, and a combination of conjoined intramedullary pins with an ESF. An acceptable outcome was achieved in 75% (6/8) of luxated femorotibial joints managed with surgical methods. All cases were female birds of various species, suggesting a possible sex predisposition for stifle luxation.

Outcome of surgical correction of medial patellar luxation in dogs weighing less than 10 kg.

BACKGROUND: Various trochleoplasty techniques, including trochlear wedge recession (TWR) and trochlear block recession (TBR), are used to treat dogs with medial patellar luxation (MPL). However, the objective outcomes of these surgical procedures are underreported. METHODS: Medical records were obtained for dogs weighing less than 10 kg that underwent either TWR or TBR and tibial tuberosity transposition to address grade I-III MPL. Long-term (at least 1 year after the last procedure) follow-up included orthopaedic and radiographic examinations, such as osteoarthritis score (OAS), ground reaction force (GRF) analysis and canine brief pain inventory (CBPI). RESULTS: Overall, 20 dogs (26 stifles) were followed up in the long term. Minor postoperative complications, medial patellar reluxation (MPR) and intermittent lameness occurred in 46.15%, 19.23% and 15% of the dogs, respectively. MPR occurred only in TWR-treated stifles, while mean OAS increased in all groups. Using the CBPI, the owners perceived an excellent or very good outcome in 95% of dogs. LIMITATIONS: The limitations of the study include its retrospective observational nature, a lack of randomisation and a small sample size. CONCLUSION: Surgical treatment resulted in a favourable outcome. GRF analysis could detect subtle differences in weight bearing in dogs treated for MPL, which might not be apparent clinically. There might be a higher risk for reluxation for TWR. However, a larger-scale prospective study would be required to find which treatment is superior.

Cadaveric comparison of two techniques for intraoperative placement of tibial plateau levelling osteotomies in dogs.

BACKGROUND: Both tibial tuberosity fractures and deviation from the planned postoperative tibial plateau angle have been associated with poor centring of tibial plateau levelling osteotomies (TPLOs). The aim of this cadaveric study was to compare two techniques for centring the osteotomy and preserving the tibial tuberosity width (TTW). METHODS: Stifle radiographs were obtained from 20 limbs of 10 dogs. TPLO was planned on each stifle, and a two-wire technique (TWT) and a technique using the medial collateral ligament (MCL) as an intraoperative landmark were planned. The techniques were executed and marked with radiopaque pins. Further radiographs were obtained and analysed. RESULTS: On average, TWT resulted in a 20.4% increase in TTW and medial collateral ligament technique (MCLT) resulted in a 13.4% decrease. Expressed as a percentage of the radial saw size, the average error in the centring of the osteotomy arising from the TWT was 13.4% and that from the MCLT was 14.2%. LIMITATIONS: This study had a small sample size and involved a single surgeon. CONCLUSION: Neither technique reliably identified the desired centre of the osteotomy, and both had a similar magnitude of error. MCLT resulted in reduced TTW, while TWT resulted in increased TTW. A reduced TTW has been associated with an increased risk of tibial tuberosity fracture, so MCLT is not recommended for clinical use.

Delayed Life-Threatening Hemorrhage Caused by Cranial Tibial Artery Pseudoaneurysm in Two Dogs.

Two adult dogs were presented at 25 and 30 days following tibial external skeletal fixator placement (case 1) and tibial plateau leveling osteotomy (case 2), respectively. Clinical signs at presentation for each of them included acute onset lethargy, non-weight-bearing lameness, and hemorrhage at the surgical site with large hematoma formation. On admission, emergency whole blood transfusion was required in case 2 with a preoperative packed cell volume of 13%. Both dogs were diagnosed with pseudoaneurysm of the cranial tibial artery based on color Doppler ultrasonography. Additionally, computed tomography angiography was performed in one dog. Surgical treatment of the dogs included ligation of the cranial tibial artery supplying the pseudoaneurysm and curettage of hematoma. The surgery was completed without complications in case 1, but case 2 experienced inadvertent rupture of pseudoaneurysm with significant blood loss, which required another whole blood transfusion during the procedure. Both dogs had excellent functional recovery with no recurrence of clinical signs. We hypothesized that pseudoaneurysms were primarily caused by trauma secondary to placement of surgical implants or osteotomy. For orthopedic surgeons, it is important to recognize clinical signs of a potential tibial arterial pseudoaneurysm, as early surgical intervention may prevent loss of limb or life.

Evaluation of viscoelastic coagulation monitoring parameters and fibrinogen concentrations in healthy dogs undergoing stifle arthroscopy and tibial plateau leveling osteotomy.

OBJECTIVE: Evaluation of viscoelastic parameters along with Hct percentages, platelet numbers, and fibrinogen concentrations in healthy dogs undergoing elective stifle arthroscopy and tibial plateau leveling osteotomy (TPLO). These results determine if dogs are in a normal, hypocoagulable, or hypercoagulable state at 4 different time points. ANIMALS: Prospective study of 37 client-owned dogs enrolled between February 2, 2022, and November 10, 2022. METHODS: All dogs received a standardized anesthetic protocol. Patients enrolled in the study underwent stifle arthroscopy using a 3-portal technique with a TPLO performed by board-certified surgeons. Viscoelastic testing, Hct percentage, fibrinogen concentration, and platelet numbers were measured preoperatively, immediately postoperatively, 24 hours postoperatively, and 14 days postoperatively. RESULTS: Stifle arthroscopy and TPLO surgery was not associated with significant effects on viscoelastic coagulation monitoring and fibrinogen concentrations in healthy dogs when comparing the time points. CLINICAL RELEVANCE: Humans have a high risk of thrombotic events when undergoing elective orthopedic surgery and are often placed on prophylactic antithrombotic medication prior to surgery. Viscoelastic coagulation monitoring in dogs undergoing similar orthopedic procedures has been evaluated in veterinary medicine, but the effects on platelets and fibrinogen concentrations from similar orthopedic procedures and uniform anesthesia protocols have not been documented. Cranial cruciate ligament insufficiency is the most common orthopedic injury in dogs. Treatment requires elective surgical correction for the best results and improved long-term prognosis. The findings of this study suggest that similar preoperative prophylactic antithrombotic intervention is not needed for canine patients.

Biomechanical effects of cranial closing wedge osteotomy on joint stability in normal canine stifles: an ex vivo study.

BACKGROUND: Cranial closing wedge osteotomy (CCWO) is a functional stabilisation technique for cranial cruciate ligament (CrCL) ruptures. This biomechanical study aimed to evaluate the influence of CCWO on the stability of the stifle joint. Eighteen Beagle stifle joints were divided into two groups: control and CCWO. The stifle joints were analyzed using a six-degree-of-freedom robotic joint biomechanical testing system. The joints were subjected to 30 N in the craniocaudal (CrCd) drawer and proximal compression tests and 1 Nm in the internal-external (IE) rotation test. Each test was performed with an extension position, 135°, and 120° of joint angle. RESULTS: The stifle joints were tested while the CrCLs were intact and then transected. In the drawer test, the CCWO procedure, CrCL transection, and stifle joint flexion increased CrCd displacement. The CCWO procedure and CrCL transection showed an interaction effect. In the compression test, the CCWO procedure decreased and CrCL transection and stifle joint flexion increased displacement. In the IE rotation test, CCWO, CrCL transection, and stifle joint flexion increased the range of motion. CONCLUSIONS: CCWO was expected to provide stability against compressive force but does not contribute to stability in the drawer or rotational tests. In the CCWO-treated stifle joint, instability during the drawer test worsened with CrCL transection. In other words, performing the CCWO procedure when the CrCL function is present is desirable for stabilizing the stifle joint.

Estimation of footprints of the canine stifle ligaments using deformable shape templates of bones.

Knowledge regarding the ligament footprints in the canine stifle is essential for biomechanical modeling of the joint and patient-specific surgical planning for anatomical ligament reconstruction. The present study aimed to establish and evaluate deformable shape templates (DSTs) of the femur and tibia with footprints of the cruciate and collateral ligaments embedded for the noninvasive estimation of ligament footprint positions. To this end, a data set of computed tomography (CT)-derived surface models of the femur and tibia were established and used to build statistical shape models (SSMs). The contours of the stifle ligaments were obtained from CT scans of 27 hindlimb specimens with radio-opaque markings on the ligament footprints. The DST, constructed by embedding averaged footprint contours into the SSM, was used to estimate subject-specific ligament footprints in a leave-one-out cross-validation framework. The DST predictions were compared with those derived from radio-opaque-marked footprints. The results showed that the averaged Euclidean distances between the estimated and reference footprint centroids were less than 1.2 mm for the cruciate ligaments and 2.0 mm for the collateral ligaments. The DST appeared to provide a feasible alternative approach for noninvasively estimating the footprints of the stifle ligaments in vivo.

Effect of intra-articular platelet-rich plasma or hyaluronic acid on limb function recovery in dogs with TPLO for cranial cruciate ligament rupture: a randomised controlled trial.

OBJECTIVES: This study aimed to investigate the recovery of limb function following a single intra-articular injection of platelet-rich plasma or hyaluronic acid in dogs with cranial cruciate ligament rupture treated with tibial plateau levelling osteotomy compared to dogs receiving no injection intraoperatively. MATERIALS AND METHODS: Sixty-two dogs with cranial cruciate ligament rupture, body weights of 20 to 40 kg, and no other orthopaedic conditions were enrolled in this prospective, randomised, double-blind, controlled study at the small animal clinic at LMU Munich. All dogs underwent tibial plateau levelling osteotomy. Based on random allocation, they received either a single intra-articular injection of platelet-rich plasma, hyaluronic acid or no injection intraoperatively. Gait analysis, clinical examinations, radiography of the stifle joint for osteoarthritis progression and two validated owner questionnaires were compared among groups at three timepoints postoperatively (6 weeks, 3 and 6 months). Limb function was primarily assessed by measuring the ground reaction forces. RESULTS: At all times postoperatively, no differences were observed among groups regarding clinical examinations, osteoarthritis score values, ground reaction forces or owner questionnaires. All dogs showed significant improvement in limb function clinically, in all ground reaction forces and in the validated questionnaires. Osteoarthritis progressed minimally during rechecks in all dogs regardless of the additional injection or not. CLINICAL SIGNIFICANCE: All dogs treated with tibial plateau levelling osteotomy for cranial cruciate ligament rupture showed improvements in limb function. No additive effect on faster recovery was demonstrated with the additional intra-articular injection of platelet-rich plasma or hyaluronic acid. Addition of platelet-rich plasma/hyaluronic acid injections during tibial plateau levelling osteotomy is unnecessary considering the lack of benefit observed up to 6 months postoperatively.

Short-term outcomes of cranial cruciate ligament rupture treated surgically with tibial plateau leveling osteotomy or non-surgically in small-breed dogs weighing less than10 kg.

Cranial cruciate ligament rupture (CCLR) is a common cause of stifle joint pain in dogs. This study assessed the short-term outcomes in the management of CCLR, with or without concurrent medial patellar luxation (MPL), in small-breed dogs, comparing surgical intervention using tibial plateau leveling osteotomy (TPLO) with non-surgical approaches. Dogs weighing less than 10 kg and suffering from CCLR were divided into two groups: surgical and non-surgical (nine stifles per group). Both groups followed the same rehabilitation protocol. Measurements were taken on days 0, 14, 28, 42, 56, 70, and 84. These measurements included the mean difference in orthopedic assessment score (diffOAS) and thigh muscle circumference (TMC) assessed by veterinarians, as well as the Canine Brief Pain Inventory score (CBPI) evaluated by the owners. Six stifles had concurrent MPL in the surgical group and five in the non-surgical group. No significant differences were observed in diffOAS (P=0.685), TMC (P=0.557), CBPI pain severity score (P=0.062), and CBPI pain interference score (P=0.29) between the two groups. However, both groups showed a significant decrease (P<0.05) in diffOAS and CBPI. The TMC remained relatively stable in the non-surgical group (P>0.05), but it significantly increased in the surgical group (P<0.05). Both groups demonstrated improved clinical outcomes in the short term, with no significant differences. However, cautious consideration should be given to a conservative treatment in small-breed dogs, particularly when considering the exclusive improvement observed in TMC within the TPLO group.

Novel crescentic, medial-closing, medially translating, centre-of-rotation-of-angulation-based, levelling osteotomy for lateral compartment stifle disease with partial cranial cruciate ligament tear in two dogs.

CASE HISTORY: Two mature, large breed dogs presented with chronic lameness and discomfort localised to the stifle. CLINICAL FINDINGS: No hindlimb deformities were present on physical examination or radiographic evaluation. No stifle instability was present. Arthroscopy revealed severe (grade 5/5 modified Outerbridge score) cartilage erosion in the lateral compartment (femorotibial), marked degeneration of the lateral meniscus and early cranial cruciate ligament disease in both patients. TREATMENT AND OUTCOME: Medial-closing, medially translating, centre-of-rotation-of-angulation-based, levelling osteotomy (mcmtCBLO) was performed in both patients. The procedure aims to shift the pelvic limb's mechanical axis medially to reduce pressure in the lateral compartment while also reducing craniocaudal shear forces by lowering the tibial plateau angle.Eight weeks after surgery one patient's lameness had resolved while the other had improved significantly. Second-look arthroscopy performed at this time revealed fibrocartilage formation in the lateral compartment without progression of cruciate disease in both cases. At long-term follow-up (approximately 3 and 5 years), favourable outcomes (no or minimal lameness, mild or moderate osteoarthritis) were identified on the long-term owner survey, lameness examination and radiographs. CLINICAL RELEVANCE: mcmtCBLO reduced or eliminated short- and long-term lameness in these two cases afflicted by concurrent lateral compartment and early cranial cruciate ligament disease.

TTA-Rapid for treating the canine cruciate deficient stifle: Medium to long-term outcome and analysis of risk factors.

BACKGROUND: This study aimed to evaluate medium to long-term outcomes following treatment of lameness associated with cranial cruciate ligament insufficiency using the tibial tuberosity advancement (TTA)-Rapid technique and to investigate risk factors associated with outcome, including tibial plateau angle (TPA). METHODS: Patient records for cases treated over an 80-month period were examined retrospectively. An owner postal questionnaire using a clinical metrology instrument (Liverpool Osteoarthritis in Dogs) evaluated the outcome at least 6 months after surgery. RESULTS: A total of 149 procedures were carried out in 120 dogs. Questionnaires were received for 64 dogs (53.3%), with a median follow-up time of 37.5 months. Outcome was judged to be satisfactory, based on frequency of lameness, in 63 (98.4%), while satisfactory outcomes were achieved in 61 (95.3%) based on severity of lameness and in 50 (78.1%) based on mobility score. Statistical analysis showed that age, bodyweight, TPA, meniscal injury and concurrent patellar surgery did not influence outcome, but time to follow-up positively correlated with mobility score. LIMITATIONS: This study involved one surgeon in one centre with outcome data based on the completion of an owner questionnaire, although this used a validated clinical metrology instrument. CONCLUSION: TTA-Rapid offers a treatment option for cranial cruciate-deficient stifles with a good medium to long-term outcome, and no risk factors were identified to suggest any limitations to its use.

In Vitro Assessment of Compression Patterns Using Different Methods to Achieve Interfragmentary Compression during Tibial Plateau Levelling Osteotomy.

OBJECTIVES: The aim of this study was to evaluate and characterize different methods to achieve interfragmentary compression during tibial plateau levelling osteotomy (TPLO). STUDY DESIGN: TPLO was performed in 20 canine tibia models (Sawbones, Vashon, Washington, United States) using 3D-printed guides for standardization. Interfragmentary compression was assessed using pressure-sensitive films (Prescale, Fujifilm, Atherstone, United Kingdom). Seven compression methods were tested: (1) Kern bone holding forceps clamping the craniodistal aspect of the TPLO plate to the caudal aspect of the tibia (K); (2) using the distal TPLO plate dynamic compression hole (P); (3) pointed bone reduction forceps engaging the caudal aspect of the proximal bone fragment and the cranial aspect of the tibial crest (F); (4) K + P; (5) K + F; (6) F + P; and (7) K + F + P. Five measurements were obtained for each method, and each bone model was used for two measurements (single method, ± plate). The interfragmentary surface was digitalized and divided into quadrants for standardization and pixel density calculation: Q1, craniomedial; Q2, craniolateral; Q3, caudomedial; and Q4, caudolateral. One-way analysis of variance (ANOVA) and post hoc tests were used for statistical analysis. RESULTS: Mean pressures per quadrant differed significantly between methods (p < 0.001). Methods K, F, and P produced more craniomedial, craniolateral, and caudal compression, respectively. Method K resulted in loss of caudal compression (p < 0.001). Method F + P provided the most even distribution of high interfragmentary compression forces. The addition of method K to this construct (K + F + P) marginally increased cranial compression (p = 0.189 for Q1; p < 0.001 for Q2), but reduced compression caudally (p < 0.001). CONCLUSION: Method F + P provided more even interfragmentary compression. If method K were used, then combined use with method F + P would be recommended.

The effects of tibial tuberosity avulsion and repair on tibial plateau angle in dogs.

AIMS: To assess whether tibial tuberosity avulsion injury and subsequent surgical repair in skeletally immature dogs are associated with changes in tibial plateau angle (TPA) at skeletal maturity. METHODS: Skeletally mature (> 18 months of age) dogs that had previously undergone unilateral surgery when 4-8 months of age to repair tibial tuberosity avulsion were enrolled. Bilateral, mediolateral stifle radiographs were taken. TPA was measured digitally from the radiographs independently by two readers and compared between sides within dogs. As the number of dogs that would be enrolled for the main part of the study was unknown, to understand how the variation between left and right stifles within dogs would affect the power of the main study, 29 client-owned, skeletally mature dogs without stifle pathology were recruited prior to the main study for bilateral, mediolateral projection stifle radiographs. Variation in the differences in TPA between left and right stifles was used to estimate the likely power of the major part of the study for different numbers of enrolled dogs. RESULTS: From 29 dogs enrolled in the power assessment, the SD of the differences between left and right stifles was 2.1°. With 10 dogs (20 stifles) enrolled within the main part of the study, and if the SD of the differences between operated and non-operated stifles within a dog was the same as the SD of the differences between non-operated stifles within a dog (2.1°), the study would have power ≥ 0.8 if the mean difference in TPA between operated and non-operated stifles was ≥ 2.1°.Ten dogs were enrolled in phase II of the study. In 8/10 of these dogs, the TPA in the operated stifle was less than in the non-operated stifle. The mean TPA on the operated stifle was 6.4° less than on the non-operated stifle (95% CI = 2.4-10.3° less; p = 0.002). For surgery between 4 and 8 months of age, TPA at maturity increased by 2.7° (95% CI = 1.1-4.3°; p = 0.001) for each additional month of age at surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Based on this study, surgical repair of tibial tuberosity avulsion in skeletally immature dogs is associated with a smaller TPA at skeletal maturity. However, causality cannot be established from this cross-sectional study, and this association may be because stifles with a smaller TPA are predisposed to tibial tuberosity avulsion.

Intra-articular Fibrolipoma of the Stifle in a Dog.

A 12 yr old male castrated miniature Australian shepherd dog presented for surgical consultation of historical bilateral medial patellar luxations with a 3 mo history of an acute onset of a left pelvic limb lameness. Physical examination confirmed medial patellar luxations and a mass effect of the left stifle medially. Radiographs showed medial distension of the joint capsule by a soft tissue opacity. Fine-needle aspirate of the left stifle revealed a mesenchymal cell population. Left medial parapatellar stifle arthrotomy found a fatty mass, which was excised at its base. A benign fibrolipoma was diagnosed on histopathology, and the excision was expected to be curative. The owners reported immediate improvement of perceived comfort postoperatively. At 2 and 24 wk, the dog returned to a normal level of function. Lipomas of the stifle, although rare, should be considered as a differential for intra-articular masses causing lameness.

Cranial closing wedge ostectomies for management of canine cranial cruciate ligament insufficiency: Comparison and geometric modelling of errors.

Variants of the cranial closing wedge ostectomy (CCWO) may be used to manage cranial cruciate ligament deficient stifles by reduction of the tibial plateau angle (TPA). Concerns have been raised about predictability of achieving target TPA, limb shortening, axis shift, and distalization of the tibial tuberosity. Landmarks derived from tibial radiographs (n = 50) by 5 observers, along with outlines of the cranial and caudal proximal tibial cortices, were used to simulate six CCWO variants. Tested variants were Slocum-type (n = 2), modified (n = 2), isosceles, and anatomical-mechanical axis (AMA)-based CCWO. Observer specific landmarks were used to model pre- and postoperative errors in TPA measurement. Mean landmarks were used to compare key outcome variables between the variants, as well as modelling errors in positioning the wedge apex. Variants differed markedly in TPA, axis shift, mechanical axis length changes, and tibial tuberosity distalization, with more proximally positioned wedges performing better than distally positioned wedges. Errors in TPA identification appeared partially self-correcting due to altered axis shifts. Craniocaudal shifts in wedge apex position had the most severe effects on outcome variables, especially in shorter tibiae with greater initial TPA values. Recent CCWO variants are likely to achieve a satisfactory postoperative TPA with limited axis shift. The AMA-based CCWO technique appears to influence MA length and tibial tuberosity position the least, and apart from the effect on TPA where no advantage could be discerned, it appeared more robust in the face of wedge apex positioning errors than the other techniques.

Diagnosis of medial meniscal lesions in the canine stifle using multidetector computed tomographic positive-contrast arthrography.

OBJECTIVE: To assess diagnostic value and clinical utility of multidetector computed tomographic positive contrast arthrography (CTA) for meniscal lesions in dogs. STUDY DESIGN: Prospective case series. STUDY POPULATION: Client-owned dogs (n = 55) with cranial cruciate ligament injuries. METHODS: Sedated dogs underwent CTA using a 16-slice scanner, and subsequently received mini-medial arthrotomy for meniscal assessment. Scans were anonymized, randomized, and reviewed twice for meniscal lesions by three independent observers with varying experience. Results were compared with surgical findings. Reproducibility and repeatability were assessed with kappa statistics, intraobserver changes in diagnosis by McNemar's test, and interobserver differences using Cochran's Q test. Test performance was calculated using sensitivity, specificity, proportion correctly identified, and positive and negative predictive values and likelihood ratios. RESULTS: Analysis was based on 52 scans from 44 dogs. Sensitivity for identifying meniscal lesions was 0.62-1.00 and specificity was 0.70-0.96. Intraobserver agreement was 0.50-0.78, and interobserver agreement was 0.47-0.83. There was a significant change between readings one and two for the least experienced observers (p < .05). The sum of sensitivity and specificity exceeded 1.5 for both readings and all observers. CONCLUSION: Diagnostic performance was suitable for identifying meniscal lesions. An effect of experience and learning was seen in this study.

A mismatch of planning and achieved tibial plateau angle in cranial closing wedge surgery: An in silico and clinical evaluation of 100 cases.

OBJECTIVE: (1) To determine whether Oxley's modified cranial closing wedge osteotomy (CCWO) results in a tibial plateau angle (TPA) of 5° in silico, (2) compare in silico to clinical postoperative TPA and (3) determine the impact of ostectomy distalization in silico. STUDY DESIGN: Cross-sectional retrospective radiographic in silico study. SAMPLE POPULATION: A total of 100 stifle radiographs; 90 dogs (small ≤25 kg = 84; large >25 kg = 16). METHODS: Tibial plateau angles were measured preoperatively (TPAPre ), after in silico planning (TPAPlan ), and postoperatively (TPAPost ). Virtual ostectomies were evaluated for plate fit. Postoperative ostectomy position was measured. Virtual ostectomies were performed 5/7.5/10/15 mm from the patellar tendon insertion in 10 dogs from each preoperative TPA category (≤20°/21-25°/ 26-30°/31-35°/>35°). Comparisons for TPAPre , TPAPost , and TPAPlan were made between small and large dogs, and the outcome to the target 5° between TPA categories and ostectomy positions. RESULTS: Mean ± SD TPAPre was 28.6 ± 6.2° and higher in small than large dogs. Mean TPAPlan was 7.6 ± 2.7°. Plate fit was appropriate in all. In silico, TPAs were greater than 5° except for cases with TPAPre > 35°. Median TPAPost was 5.5° (-4-21) and was higher in small (7°) than large (4.5°) dogs. Postoperative ostectomy position was more distal than Oxley's guidelines. When distalized >7.5 mm in silico, the magnitude of under-correction increased. CONCLUSIONS: Oxley's modified CCWO did not result in TPA of 5° in most cases. Ostectomy distalization exacerbated under-correction. CLINICAL IMPACT: Current guidelines should be modified to achieve 5° TPA postoperatively.

Complications and Long-Term Outcomes after Combined Tibial Plateau Leveling Osteotomy and Tibial Tuberosity Transposition for Treatment of Concurrent Cranial Cruciate Ligament Rupture and Grade III or IV Medial Patellar Luxation.

OBJECTIVES: This study aims to report complications and long-term outcomes of combined tibial plateau leveling osteotomy and tibial tuberosity transposition (TPLO-TTT) for treatment of concurrent cranial cruciate ligament rupture and medial patellar luxation (MPL). STUDY DESIGN: This is a retrospective study. Dogs that underwent TPLO-TTT for treatment of combined cranial cruciate ligament rupture and grade III or IV MPL were included. Signalment, fixation method, and complications were recorded. Long-term outcome assessment (minimum 1 year postoperatively) was performed through clinical and radiographic reexamination at the authors' institution. RESULTS: Twenty-four stifles (22 dogs) were included. Twenty-one stifles had a grade III MPL, and 3 stifles had grade IV MPL. Four major complications consisting of surgical site infection (n = 3) and recurrent grade II MPL (n = 1) were observed. Dogs with surgical site infections were successfully treated with implant removal and oral antibiotics. No additional surgery was performed for the patient with recurrent MPL as no signs of lameness were observed. Minor complications occurred in five cases. At long-term evaluation (median: 27 months; range: 12-67 months), 21/22 dogs were clinically sound and 23/24 stifles had a complete resolution of MPL. CONCLUSION: TPLO-TTT can be considered as an effective surgical option to treat patients with concurrent cranial cruciate ligament rupture and MPL with a relatively low major complication rate. Owners should be warned of the potential need for implant removal.

Trochlear Ridge Prostheses for Reshaping Femoral Trochlear Ridges in Dogs with Patellar Luxation.

OBJECTIVES: To describe the implant characteristics and surgical application of a custom-made trochlear ridge prosthesis (TRP) and to report clinical outcomes in dogs affected by patellar luxation treated with TRP. STUDY DESIGN: Dogs affected by patellar luxation underwent computed tomography. A specific canine bone anatomical replica, a cutting guide, and a TRP were designed and provided for surgery. Surgical records, clinical and radiographic reassessments, complications, pre- and postoperative lameness, type and degree of patellar luxation, and TRP and patellar position after surgery were reviewed. Clinical outcomes were defined as full, acceptable, or unacceptable function. RESULTS: The TRP was implanted in 60 femoral trochleae: 48 unilateral and 12 bilateral. Successful correction of patellar luxation was achieved in 59/60 cases. TRP was applied with other surgical techniques in 36/60 of the cases and as the only surgical procedure in 24/60 cases. Overall, three complications were observed: two minor and one major (patellar luxation recurrence). Neither implant loosening nor infection was observed. The mean radiographic follow-up was 3.8 months. At the time of the final follow-up, 57/60 cases were scored as fully functional. CONCLUSION: The TRP application either alone or in combination with other surgical techniques allowed for correction of patellar luxation and improvement in preoperative lameness with nominal complications. TRP could represent a potentially reliable alternative to trochleoplasty.

Photobiomodulation therapy in dogs undergoing TPLO after cranial cruciate ligament rupture shows promise but no statistically significant difference in a randomized trial.

OBJECTIVE: Effect of photobiomodulation therapy (PBMT) in patients with CCLR after TPLO surgery by measuring C-reactive protein (CRP), percentage weight bearing, lameness using a short form of a composite measure pain scale, evaluated by the clinician and owners, and surgical site infection. SAMPLE: 54 client-owned dogs with CCLR undergoing unilateral TPLO surgery were enrolled in this study between April 5, 2021, through April 10, 2022. METHODS: The study population was randomly assigned to either a treatment group receiving PMBT (24 dogs) or a control group (30 dogs). PMBT was performed on the treatment group immediately after induction, and 6 hours, 24 hours, 48 hours, and 8 weeks postoperatively. The control group received sham PMBT (device turned off) at the same time. Evaluation of CRP, CMPS-SF, evidence of SSI, and %WB were evaluated for all dogs 24 hours preoperatively, and then 24 hours, 48 hours, and 8 weeks postoperatively. Owners completed CMPS-SF and subjective evaluations weekly for 8 weeks postoperatively. RESULTS: No statistically significant differences were found between treatment groups when evaluating CRP, %WB, and CMPS-SF by the clinician and weekly evaluation of the CMPS-SF by owners. Although no statistically significant differences were found in patients developing surgical site infections between treatment groups, SSI was only observed in patients in the control group (5/30, 16.6%). Most were minor/superficial infections (4/30 13.3%), and a single dog (1/30, 3.3%) had a major/deep surgical site infection. CLINICAL RELEVANCE: Although with promising but not statistically significant differences between groups, surgical site infections may be reduced after PBMT application.