The impact of surgery resident training on the duration of tibial plateau leveling osteotomy surgery

OBJECTIVE

To investigate the impact of surgery resident training on surgery duration in tibial plateau leveling osteotomy (TPLO) and evaluate whether surgery duration differs with each year of residency training.

STUDY DESIGN

Retrospective medical record review.

ANIMALS

A total of 256 client-owned dogs underwent TPLO.

METHODS

Records of dogs that underwent TPLO between August 2019 and August 2022 were reviewed. The effects of the surgeon (faculty/resident) and the procedure (arthrotomy/arthroscopy) on TPLO surgery duration were examined with an analysis of variance, and geometric least squares means (GLSM) were compared. A linear mixed effects model (LMM) was fitted to quantify fixed and random effects.

RESULTS

Four faculty surgeons performed 74 (29%) TPLOs, while 10 residents performed 182 (71%) TPLOs under the direct supervision of a faculty surgeon. All TPLOs were conducted with arthrotomy (109; 43%) or arthroscopy (147; 57%). Overall, residents (GLSM, 153 min) required 54% more surgery duration than faculty surgeons (GLSM, 99 min). Surgery duration among first-year residents (GLSM, 170 min) was 15% longer than second- (GLSM, 148 min) and third-year (GLSM, 147 min) residents, whereas the duration did not differ statistically between second- and third-year residents. Arthroscopy, meniscal tear treatment, surgery on the right stifle, and increasing patient weight were also associated with longer surgery duration.

CONCLUSION

The duration of TPLO surgery significantly decreased after the first year of residency, but did not decrease afterward.

CLINICAL SIGNIFICANCE

The results will aid with resource allocation, curricula planning, and cost management associated with resident training.

Effect of center of rotation of angulation-based levelling osteotomy on instantaneous center of rotation ex vivo

Cranial cruciate ligament rupture is a common cause of femorotibial instability in dogs. Despite numerous techniques being described for achieving joint stabilization, no consensus exists on the optimal management strategy. This ex vivo study utilized the path of the instantaneous center of rotation (ICR) to compare normal, pathological and treated joints. Fluoroscopic recordings of seven limbs from a previous study of canine stifle joint stability following center of rotation of angulation-based levelling osteotomy (CBLO) with and without hamstring loading were analyzed using least-squares approximation of the ICR and estimation of percentage gliding (vs. rolling) to determine if alterations in ICR path and gliding caused by CCL transection and following meniscal release could be normalized by CBLO. In intact joints, the ICR path was located mid-condyle, but this shifted significantly proximally and caudally following CCL transection and medial meniscal release (p < 0.007, p < 0.04). Hamstring loading resulted in qualitative and some quantitative improvements in joint movement based on percentage gliding movement analysis. The ICR path after CBLO remained significantly different to the intact location with or without a hamstring load (p < 0.02, p < 0.04), potentially consistent with CBLO aims of mild residual instability. CBLO resulted in percentage gliding characteristics not significantly different to intact joints (p > 0.08). Qualitative improvements in ICR path and percentage gliding quantities and variability suggest that hamstring loading positively influences joint biomechanics and that further investigation of this role ex vivo and clinically is warranted.

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.

Evaluation of the Effects of an Undenatured Collagen Type-2-Based Nutraceutical (ARTHROSHINE® HA²) on Recovery Time after TPLO in Dogs: A Prospective, Randomized Study with Objective Gait Analysis as the Primary Outcome Measure

This randomized, prospective clinical trial investigates the impact of a novel undenatured collagen type 2 (T2NDC)-based nutraceutical, ARTHROSHINE® HA² (AS), on postoperative rehabilitation following Tibial Plateau Leveling Osteotomy (TPLO) in 50 dogs with unilateral cranial cruciate ligament rupture (CCLR). The patients were randomly allocated to either group A, receiving AS once daily for 24 weeks post-TPLO surgery, or group B, without any supplementation. Frequency matching was applied to enhance group comparability. Assessment of outcomes included computerized gait analysis and a validated owner questionnaire. AS supplementation was well received, without any reported side effect. Consistently, patients in group A exhibited significantly higher peak vertical force values during all follow-up assessments. By the 12-week mark, gait analysis indicated a return to a physiological gait pattern in group A, while group B achieved this normalization only by the 24-week point. The administration of AS post-TPLO surgery demonstrates promise in enhancing limb function, leading to faster restoration of a physiological gait pattern. The inclusion of AS, a T2NDC-based nutraceutical, in the post-TPLO rehabilitation protocol may contribute to improved limb function and an expedited recovery, potentially facilitating a quicker return to normalcy. It is noteworthy that subjective owner perceptions did not differ between the two groups.

Pressure-Sensitive Walkway System for Evaluation of Lameness in Dogs Affected by Unilateral Cranial Cruciate Ligament Rupture Treated with Porous Tibial Tuberosity Advancement

The aim of this study was to objectively evaluate lameness in dogs affected by a unilateral cranial cruciate ligament rupture (CrCLR) treated with porous tibial tuberosity advancement before surgery and at three different timepoints after surgery, using the GAITRite® system (version 4.9Wr), a pressure-sensitive walkway system that is able to calculate several spatiotemporal gait parameters simultaneously for each limb. The dogs walked on the pressure-sensitive walkway before (T0) and 30 (T1), 90 (T2), and 120 (T3) days after surgery. Pressure measurements (gait lameness score and total pressure index %) were collected for S (treated with porous TTA) and C (healthy contralateral limb) at T0, T1, T2, and T3 and statistically evaluated. An ANOVA test was performed to compare the data, and a value of p < 0.05 was considered significant. Twenty dogs (n = 20) of various common breeds and ages with CrCLR were enrolled in the study. The results showed that there was a statistically significant difference in the GAIT4Dog® lameness score (GLS) and TPI% between S and C for each timepoint. Statistically significant differences in the GLS and TPI% between S at T0 and S at T2 and between S at T0 and S at T3 (p < 0.001) were found. The results showed that there was a statistically significant difference in the GAIT4Dog® lameness score (GLS) and TPI% between S and C for each timepoint. Statistically significant differences in the GLS and TPI% between S at T0 and S at T2 and between S at T0 and S at T3 were found. The GLS and TPI% increased statistically significantly from 90 days after surgery compared to the preoperative measurements. Moreover, comparing the GLS and TPI% between the treated limb and the control limb showed that a statistically significant difference remained at each timepoint.

Radiographic Comparison of Virtual Surgical Corrective Options for Excessive Tibial Plateau Angle in the Dog

OBJECTIVE

 The main aim of this study is to compare the impact of six proximal tibial osteotomies on the geometry and alignment of tibias with and without excessive tibial plateau angle (TPA).

STUDY DESIGN

 Mediolateral radiographs of 30 canine tibias were divided into three groups (n = 10/group): moderate TPA (≤34 degrees), severe TPA (34.1-44 degrees) and extreme TPA (>44 degrees). Six proximal tibial osteotomies were simulated on each tibia using orthopaedic planning software: cranial closing wedge ostectomy (CCWO), modified CCWO (mCCWO), isosceles CCWO (iCCWO), neutral isosceles CCWO (niCCWO), tibial plateau levelling osteotomy with CCWO (TPLO/CCWO) and coplanar centre of rotation of angulation-based levelling osteotomy (coCBLO). All tibias were reduced to a standard target TPA. Pre- and postoperative measurements were obtained for each virtual correction. Compared outcome measures included tibial long axis shift (TLAS), cranial tibial tuberosity shift (cTTS), distal tibial tuberosity shift (dTTS), tibial shortening and osteotomy overlap.

RESULTS

 Across all TPA groups, TPLO/CCWO had the lowest mean TLAS (1.4 mm) and dTTS (6.8 mm); coCBLO had the largest TLAS (6.5 mm) and cTTS (13.1 mm); CCWO had the largest dTTS (29.5 mm). CCWO had the largest degree of tibial shortening of 6.5 mm, while mCCWO, niCCWO and coCBLO resulted in minimal tibial lengthening (1.8-3.0 mm). These trends were generally conserved across different TPA groups. All findings had a p-value less than 0.05.

CONCLUSION

 mCCWO balances moderate alterations to tibial geometry while preserving osteotomy overlap. The TPLO/CCWO has the least effect on tibial morphology alteration, whereas the coCBLO results in the largest alteration.

Instantaneous center of rotation in the canine femorotibial joint: Ex vivo assessment of a tool to evaluate joint stabilization surgeries

Cranial cruciate ligament rupture is a common cause of femorotibial joint instability in the dog. Numerous techniques including several tibial osteotomies have been described for stabilization, but there is no current consensus on the best method. The instantaneous center of rotation (ICR) can aid investigations of pathological joint movement, but its use is problematic in the femorotibial joint due to combined rotation and translation during flexion and extension. Using fluoroscopic images from an earlier cadaveric study of canine joint stability, an interpolation method was used to create repeatable rotational steps across joint situations, followed by least squares approximation of the ICR. The ICR in intact joints was located mid-condyle but displaced significantly (P < 0.001) proximally following cranial cruciate ligament transection and medial meniscal release. Individual joints appear to respond differently to destabilization. Triple tibial osteotomy partially restored ICR location during early movement from flexion to extension. Joint instability significantly altered the proportions of rolling and gliding movement at the joint surface (P < 0.02), which triple tibial osteotomy partially improved. While triple tibial osteotomy restores joint stability ex vivo and clinically, normal biomechanics of the joint are not restored. The methods described here may prove useful for comparison of osteotomy techniques for stabilization of the cranial cruciate ligament deficient femorotibial joint in dogs.

Ex vivo biomechanical evaluation of extracapsular stabilization with quasi-isometric points in canine cranial cruciate ligament-deficient stifles

BACKGROUND

Cranial cruciate ligament (CCL) disease is one of the most common causes of lameness in dogs. The extracapsular stabilization (ECS) utilizing bone anchors and monofilament nylon leader was an alternative treatment for CCL-deficient (CCLD) dogs. However, the biomechanical response of the canine stifle to such a surgical repair strategy in conjunction with the use of recently reported quasi-isometric anchoring points remains unclear. The objectives of the study were to evaluate the mobility and stability of CCL-intact, CCLD, and CCLD stifles repaired with ECS at two different pairs of quasi-isometric points (quasi-IPs).

METHODS

Twelve stifle specimens from 7 dogs underwent mobility and stability tests under 4 different conditions, namely, CCL-intact, CCLD, and ECS-repaired at 2 different pairs of quasi-IPs (referred to as ECS-IP1 and ECS-IP2). The mobility tests evaluated 6 degrees-of-freedom stifle kinematics during flexion and extension. The stability tests involved cranial drawer and tibial internal rotation (IR) tests at various stifle opening angles and quantifying the cranial tibial translation (CTT) and tibial IR angles under constantly applied loadings.

RESULTS

The ECS repaired at quasi-IPs was shown to restore cranial instability of the stifles with averaged CTT magnitudes < 1.4 mm. During the tibial IR test, the ECS treatments resulted in significantly less tibial IR compared to those in intact CCL stifles. The mobility tests showed similar results.

CONCLUSION

The 2 chosen pairs of quasi-IPs were shown to effectively correct the excessive CTT caused by CCLD stifles, whereas the excessive tibial external rotation in comparison to those of intact stifles should be considered for its subsequent influence on joint alignment and the contact pressure applied to the stifle joint.

Pelvic limb anesthesia and analgesia in dogs undergoing tibial plateau leveling osteotomy (TPLO): A survey of board-certified anesthesiologists

OBJECTIVE

To report the locoregional anesthesia and analgesia preferences of veterinary anesthesiologists for use in dogs undergoing a TPLO and determine any association with specialty college, time from board-certification, or employment sector.

STUDY DESIGN

Cross sectional study.

SAMPLE POPULATION

Diplomates of the American (ACVAA) and European (ECVAA) Colleges of Veterinary Anesthesia and Analgesia.

METHODS

An electronic survey was distributed to diplomates and responses were used to determine associations between preferred methods.

RESULTS

The survey response rate was 28% (141/500) with 69% (97/141) of ACVAA diplomates and 31% of diplomates with ECVAA (44/141) certification. Peripheral nerve block (PNB) was preferred by 79% (111/141) of all diplomates, lumbosacral epidural (LE) by 21% (29/141), and peri-incisional infiltration (PI) by <1% (1/141). There was no association (p = .283) with specialty college. There was an association (p < .001) with time from board-certification with increased preference for LE when >10-years from certification and PI preferred by only those board-certified >20-years ago. There was an association with employment sector (p = .003) with more academic diplomates preferring LE. Anesthesiologists reported that treatment decisions were affected by various factors including time pressure and surgeon influence.

CONCLUSION

Diplomates of ACVAA and ECVAA prefer PNB as the locoregional method of pelvic limb anesthesia in dogs undergoing TPLO. A greater percentage of newer and private practice diplomates prefer PNB while a larger percentage of senior and academic diplomates prefer LE. Decision making is multifactorial and includes perceived time pressure and surgeon influence.

CLINICAL SIGNIFICANCE

Veterinary anesthesiologists prefer and frequently use PNB in dogs undergoing TPLO and surgeon influence may affect their chosen treatment.

Plasma procalcitonin kinetics in healthy dogs and dogs undergoing tibial plateau leveling osteotomy

BACKGROUND

Procalcitonin (PCT) is a well-established biomarker for bacterial infection in human patients.

OBJECTIVES

We aimed to analyze the kinetics of plasma PCT (pPCT) in healthy dogs and dogs with canine cranial cruciate ligament (CCL) rupture undergoing tibial plateau leveling osteotomy (TPLO).

METHODS

This prospective, longitudinal study included 15 healthy dogs and 25 dogs undergoing TPLO. Hematology, pPCT, and C-reactive protein (CRP) were assessed on 3 consecutive days in healthy dogs and 1 day preoperatively and days 1, 2, 10, and 56 postoperatively. Inter- and intraindividual variability of pPCT were assessed in healthy dogs. Median pPCT concentrations of dogs with CCL rupture preoperatively were compared with healthy controls, and median pPCT concentrations, as well as percentage change post anesthesia, arthroscopy, and TPLO, were compared with baseline. For the correlation analysis, the Spearman rank correlation test was used.

RESULTS

Inter- and intraindividual variabilities of pPCT in healthy dogs were 36% and 15%, respectively. Median baseline pPCT concentrations were not significantly different between healthy dogs (118.9 pg/mL; IQR: 75.3-157.3 pg/mL) and dogs undergoing TPLO (95.9 pg/mL; IQR: 63.8-117.0 pg/mL). Plasma PCT concentrations were significantly lower immediately post- than preoperatively (P < 0.001). CRP, WBC, and neutrophil concentrations increased significantly on post-OP day 2 and had normalized by day 10.

CONCLUSIONS

These results indicate that CCL rupture, as well as anesthesia, arthroscopy, and TPLO combined, are not associated with increased pPCT concentrations in dogs with uncomplicated recovery. Considering the high intraindividual variability, individual serial measurements rather than a population-based reference interval should be considered.

Patellar Proximo-Distal Displacement following Modified Maquet Technique Is Not Predictive of Patellar Luxation

OBJECTIVE

The aim of this study was to test the low sensitivity of the Allberg and Miles index to the stifle opening angle, evaluate the displacement of the patella after a Modified Maquet Technique using this index and assess the incidence of patellar luxation post-Modified Maquet Technique in dogs.

STUDY DESIGN

 Medical records were reviewed from 2012 to 2017. Allberg Miles index were determined for each stifle pre- and postoperatively, as well as the stifle joint opening of each case. Occurrence of patellar luxation was recorded.

RESULTS

 137 stifles on 116 dogs were reviewed. The stifle opening angle did not influence the Allberg Miles index. Pre- and postoperative index showed a distal displacement of the patella after a Modified Maquet Procedure, especially at 135° of stifle opening angle. Only 1/137 cases demonstrated patellar luxation after the surgery.

CONCLUSION

 Based on our statistical analysis, we were able to conclude that within the maximum stifle opening angle range recorded in our series of cases; the Allberg Miles index variation was not significant. While patellar baja is clearly induced by the Modified Maquet Technique, the latter did not seem to predispose patients to post-operative patellar luxation in our study population.

Effects of Angled Dynamic Compression Holes in a Tibial Plateau Levelling Osteotomy Plate on Cranially Directed Fragment Displacement

OBJECTIVE

 To compare angled dynamic compression holes in a tibial plateau levelling osteotomy (TPLO) plate to a commercially available TPLO plate in an ovine cadaveric model.

STUDY DESIGN

 Ovine tibias (40 bones) were mounted on a custom-made securement device and radiopaque markers were placed to aid radiographic measurements. A standard TPLO procedure was performed on each tibia with either a custom-made six-hole 3.5 mm angled compression hole plate (APlate) or a six-hole 3.5 mm standard commercial plate (SPlate). Radiographs were obtained before and after tightening of the cortical screws and evaluated by an observer blinded to the plate. Measurements of cranio-caudal displacement (CDisplacement), proximo-distal displacement (PDisplacement) in relation to the long axis of the tibia, and change in tibial plateau angle (TPA) were determined.

RESULTS

 CDisplacement was significantly greater in APlate (median 0.85 mm, Q1-Q3: 0.575-1.325 mm) compared to SPlate (median 0.00 mm, Q1-Q3: -0.35-0.50 mm, p < 0.0001). There were no significant differences in the PDisplacement (median 0.55 mm, Q1-Q3: 0.075-1.00 mm, p = 0.5066) or TPA change (median -0.50°, Q1-Q3: -1.225-0.25°, p = 0.1846) between the two plate types.

CONCLUSION

 APlate increases cranially directed displacement of the osteotomy in a TPLO procedure without causing TPA change. The reduced interfragmentary distance across the whole osteotomy could improve osteotomy healing compared to standard commercial TPLO plates.

The Effect of Location of a Unicortical Defect on the Mechanical Properties of Rabbit Tibiae: A Model of the Distal Jig Pin Hole in Tibial Plateau Levelling Osteotomy

OBJECTIVE

 The aim of this study was to determine the effect of a unicortical defect at either the mid-diaphysis (MD) or distal metaphysis (DM) on the torsional properties of tibiae in an in vitro rabbit model, and to further examine optimal distal jig pin position for the canine tibial plateau levelling osteotomy (TPLO) procedure.

STUDY DESIGN

 Thirty-eight tibiae from 19 skeletally mature female New Zealand White rabbits were assigned to one of three groups; Group 1: intact, Group 2: MD defect and Group 3: DM defect. Defects were created using a 1.6 mm Ellis pin. Pure torsion was applied to each sample and peak torque and angular displacement recorded.

RESULTS

 All tibiae fractured in a spiral configuration. Fracture lines involved the defect in 33% of the MD samples and 0% of the DM samples. No differences were detected for peak torque and stiffness between groups. However, energy (mean ± standard deviation) was significantly reduced (p = 0.028) in the MD group (0.18 ± 0.07) relative to the intact tibia group (0.31 ± 0.14). Angle was also significantly reduced (p = 0.040) in the MD group (0.17 ± 0.05) compared with the intact group (0.23 ± 0.07). Placement of a DM defect had no significant effect on mechanical properties of the rabbit tibiae.

CONCLUSION

 Defects placed in the MD significantly reduced energy and angle in comparison to intact samples. No significant difference in peak torque or stiffness was observed between groups. If canine tibiae were similarly affected, our findings suggest jig pin placement in the DM to have a lesser effect on the torsional properties of the tibiae.

Surgical site infection after 769 Tibial Plateau Leveling Osteotomies

Objective

To report surgical site infections (SSI) after Tibial Plateau Leveling Osteotomy (TPLO), treatment course, associated risk factors, bacterial isolates and antimicrobial resistance.

Study design

Retrospective clinical cohort study.

Study population

Six hundred and twenty seven dogs and 769 TPLO procedures.

Methods

Data from electronic medical records of dogs undergoing TPLO between 2005 and 2015 at a single institution have been retrospectively reviewed. A generalized mixed logistic regression was used to determine possible risk factors. The Chi-Square test of independence was used to examine the relationship between the isolation of multidrug-resistant (MDR) bacteria and the development of major infections undergoing additional surgical treatment. To assess the correlation between number of SSI and number MDR isolate per year, Pearson's correlation coefficient was calculated.

Results

The overall complication rate was 19.3% (n = 149). SSI was most frequent with 8.5% (n = 65). Major SSI occurred in 6.8% (n = 52) TPLO (80.0% SSI). Staphylococcus (S.) pseudintermedius (n = 37) and S. aureus (n = 10) were most frequently isolated. Multidrug-resistant bacteria were identified in 2.7% (n = 21) TPLO (32.3% SSI) but were not associated with major SSI (p = 0.426). There was a strong positive correlation between number of MDR isolates per year and number of SSI per year [r ₍₉₎ = 0.79, p = 0.004]. Factors associated with SSI were previous TPLO in the contralateral stifle (p = 0.02, OR = 2.01, 95% CI = 1.11-3.64) and German Shepherd dogs (p = 0.035, OR = 4.41, 95% CI = 1.11-17.54). The use of non-locking implants was found to be protective (p = 0.02, OR = 0.179, 95% CI = 0.18-0.77).

Clinical significance

Infection with multidrug-resistant bacteria is an emerging problem in veterinary practice and treatment is challenging. The incidence of major SSI was found to be high but was not associated with the isolation of MDR bacteria.

Impacts of tibial plateau levelling osteotomy on the tibial insertion of the medial collateral ligament of the canine stifle joint - A cadaveric study

OBJECTIVE

The aim of this study was to assess the potential consequences of tibial plateau levelling osteotomy (TPLO) for the medial collateral ligament (MCL) tibial insertion (TI) with a particular focus on the effects of the TPLO planning technique and of the size of saw blade.

STUDY DESIGN

Eighty-six stifle joints were collected from 43 canine cadavers and dissected free of soft tissue to expose the MCL. The MCL insertion sites were first identified with Chinese ink on intact stifle joints, and then marked with radio-opaque barium sulfate after removal of the MCL. Mediolateral radiographs were made of each marked stifle joint and used for TPLO digital planning. For each stifle, planning the TPLO was performed by centring the osteotomy at the intersection of the tibial plateau and the mechanical axis of the tibia in group 1, and at the top of the intercondylar tubercles in group 2. Whenever possible, two saw blade sizes were tested in each group. Measurements were taken after TPLO simulation to assess how the procedure would alter the MCL TI.

RESULTS

In group 1, the integrity of the MCL TI was affected by the TPLO planning in 87.2% of the cases with the small saw blade and in 59.3% of the cases with the large blade, and in group 2, in 94.2% of the cases with the small and 77.9% with the large saw blade. In group 1, the osteotomy line was located above the TI, completely severing the MCL in four cases versus in 11 cases in group 2, while severing occurred in 14/15 cases with the small saw blade.

CONCLUSION

During TPLO, the osteotomy line transected the MCL TI in the majority of dogs. Centring the osteotomy at the intersection of the tibial plateau and the mechanical axis of the tibia and using the largest saw size that preserves tibial tuberosity and patellar tendon insertion seems to be the best way to preserve the MCL TI as much as possible. Further research is needed to evaluate the clinical impact of MCL TI transection.

Complications and postoperative non-steroidal anti-inflammatory use of three extracapsular cruciate ligament repair techniques performed in a general practice clinic environment

OBJECTIVE

To report complications and postoperative non-steroidal anti-inflammatory use associated with fabellotibial suture, Tightrope and Ligafiba Isotoggle procedures performed on dogs of varying weights within a general practice setting.

MATERIALS AND METHODS

Clinical records of eligible patients from 2009 to 2018 were retrospectively extracted from five general practice clinics. Data for signalment, patient weight, surgery performed, complications, postoperative use of non-steroidal anti-inflammatory drugs, and timing thereof were extracted and analysed using multinomial logistic regression. Predicted probability tables were generated for complications and non-steroidal anti-inflammatory drug use.

RESULTS

The study included 370 surgeries, with 97 fabellotibial suture, 158 Tightrope and 42 Ligafiba Isotoggle procedures in patients less than 15 kg, and 43 fabellotibial suture, 16 Tightrope and 30 Ligafiba Isotoggle procedures in patients at least 15 kg. The proportion of patients that can be expected to have no complications was greatest for older dogs (9 years) weighing less than 15 kg (fabellotibial suture, 91%; Tightrope/Ligafiba Isotoggle, 88%), and the highest major medical and surgical complication risks were expected in young dogs (1 year) weighing over 15 kg (fabellotibial suture, 28%; Tightrope/Ligafiba Isotoggle, 59%). The predicted risk of requiring repeated non-steroidal anti-inflammatory drug prescriptions in the 18-month postoperative period for an 15 kg patient was 37% to 39%.

CONCLUSION

Weight and age were significant factors influencing complications and postoperative non-steroidal anti-inflammatory drug use in fabellotibial suture, Tightrope and Ligafiba Isotoggle surgical patients in a general practice setting.

CLINICAL SIGNIFICANCE

Clinicians should consider the possibility of complications and requirement for ongoing non-steroidal anti-inflammatory drug use before performing extracapsular procedures in patients weighing more than 15 kg.

Long-term outcome of tibial plateau leveling osteotomy using an antimicrobial silver-based coated plate in dogs

Objectives

To evaluate long-term outcome using the BioMedtrix™ TPLO Curve^® plate in dogs with cranial cruciate ligament disease (CrCLd) treated by tibial plateau leveling osteotomy (TPLO).

Study design

Retrospective case study.

Animals

Dogs (n = 323, 337 stifles).

Methods

Medical records were searched for dogs presented with CrCLd and treated by TPLO with the BioMedtrix™ TPLO Curve^® plate for 3.5 mm screws between March 2018 and December 2020. Tibial plateau angles (TPA) were measured on preoperative, postoperative, and follow-up radiographs. Changes in TPA between postoperative and follow-up radiographs (ModTPA) were calculated. Radiographic bone healing was scored. Complications were evaluated. Surgical site infections (SSI) were compared to a control group of dogs treated with the Synthes™ TPLO plate between January and December 2017. Owners of both groups were contacted by telephone at least 1 year postoperatively.

Results

The BioMedtrix™ group was composed of 237 dogs (248 stifles), the control group was composed of 86 dogs (89 stifles). In the BioMedtrix™ group, radiographic follow-up was performed at a median of 48 days. Average ModTPA was 1.2°. Bone healing was graded as complete, good, poor, and none in 18%, 62%, 20%, and 0%, respectively. At a median of 786 days postoperatively, minor and major postoperative complications were observed in 6 (2.4%) and 32 (12.9%) cases in this group, respectively. During the first year following the surgery, 23 (9.3%) and 12 (13.5%) cases suffered a SSI, of which 12 (4.8%) and 7 (7.9%) had their implant explanted in the BioMedtrix™ group and the control group, respectively. There was no significant difference between groups for SSI and implant explantations (p = 0.31 and p = 0.29, respectively).

Conclusion

The BioMedtrix™ TPLO Curve^® plate provided a reliable fixation system for osteotomy healing after TPLO. Bone healing and long-term complication rates were similar to previous studies using other implants. SSI rates were similar between the BioMedtrix™ group and the control group. The antimicrobial HyProtect^® coating of the plate did not reduce SSI in this study.

Clinical significance

The BioMedtrix™ TPLO Curve^® plate can be safely used for TPLO. The value of the antimicrobial HyProtect^® coating of the plate may be questioned, as SSI rate was not lower in this study compared to the control group or previous reports.

Combined center of rotation of angulation-based leveling osteotomy and tibial tuberosity transposition: An ex vivo mechanical study

OBJECTIVE

To describe the technique of combined center of rotation of angulation (CORA)-based leveling osteotomy (CBLO) with tibial tuberosity transposition (TTT) and to compare the load to failure between CBLO combined with TTT and CBLO or TTT alone.

STUDY DESIGN

Ex vivo study.

SAMPLE POPULATION

Twelve pairs of cadaveric pelvic limbs.

METHODS

Six pairs of cadaveric tibia were tested in each group (CBLO-TTT versus CBLO) and (CBLO-TTT versus TTT) with each limb randomly assigned to a treatment group. Construct stability was determined by applying a tensile force to each patellar tendon until failure occurred. Load at failure and mode of failure were recorded for each specimen.

RESULTS

No difference in mean load to failure was identified between CBLO-TTT (897 N) and CBLO alone (943 N) (P = .81). There was also no difference in the mean load to failure between the CBLO-TTT (928 N) and TTT alone (1046 N) (P = .12).

CONCLUSION

Performing a TTT in combination with a CBLO does not weaken the construct failure to load when compared with each procedure performed alone.

CLINICAL SIGNIFICANCE

A combined CBLO and TTT could be considered a viable option for concurrent management of a cranial cruciate ligament deficient stifle and medial patella luxation.

Center of rotation of angulation-based leveling osteotomy for stifle stabilization in skeletally immature dogs

OBJECTIVE

To describe short-term outcomes of center of rotation of angulation (CORA)-based leveling osteotomy (CBLO) in skeletally immature dogs with cranial cruciate ligament (CrCL) injury.

STUDY DESIGN

Retrospective case series.

ANIMALS

Fifteen skeletally immature dogs (16 stifles).

METHODS

Medical records of dogs with CrCL injury and radiographically documented open proximal tibial physis and tibial tuberosity apophysis managed with CBLO were reviewed. Clinical assessment, radiographic assessment, and complications were reviewed.

RESULTS

Fifteen dogs (16 stifles) with radiographically documented open proximal tibial physis and tibial tuberosity apophysis and CrCL injury underwent a CBLO. Mean tibial plateau angle (TPA) was 26° preoperatively, 9° postoperatively, and 9° at final recheck. One dog developed 10° recurvatum of the proximal tibia secondary to inadvertent over rotation of the tibial plateau (TPA 3°) to protect primary repair of an insertional CrCL avulsion. Correction of the recurvatum was declined as the dog had full limb function. Two dogs developed a valgus deformity secondary to a plate screw engaging the distolateral aspect of the proximal tibial physis. Owners of these dogs reported normal function but requested surgical revision to prevent long-term problems secondary to abnormal weight bearing. Both dogs regained full function following recovery from revision surgery. At a mean time of 23 months following surgery, all dogs continued to have full function as per phone conversation with owners.

CONCLUSION

With proper preoperative planning, CBLO is an option for skeletally immature dogs with CrCL injury.

Biomechanical comparison of screw and suture fixation for temporary transarticular tarsocrural immobilization in canine cadavers

OBJECTIVE

To biomechanically evaluate an ultrahigh-molecular-weight polyethylene (UWMWPE) suture for temporary tarsocrural immobilization as a potential alternative to the existing surgical method, which uses a 4.5 AO/ASIF calcaneotibial cortical screw.

STUDY DESIGN

Randomized in vitro biomechanical study.

ANIMALS

Pelvic limbs (n = 20) from 10 euthanized adult dogs (average bodyweight of 29.9 kg ± 1.9 kg).

METHODS

Tarsocrural joints were immobilized either with a 4.5 AO/ASIF screw or a 1 mm diameter UHMWPE suture. Limbs were loaded with 60 N, 120 N, and 180 N, each for 100 cycles. After cyclic loading, immobilizations were loaded until failure. Load at failure and mode of failure were recorded.

RESULTS

Both immobilization methods remained intact during loading with 60 N, 120 N, and 180 N. Mean and standard deviation (± SD) failure loads were higher for the cortical screw (524.9 N ± 148.7 N) than for the UHMWPE suture (387.8 N ± 105.6 N), P = .0084. The stiffness of both systems was equivalent.

CONCLUSION

Both techniques were suitable for transarticular tarsocrural immobilization in large-breed canine cadavers. While load at failure was higher for the screw compared to the suture construct, stiffness of both methods was comparable based on the laboratory settings in this in vitro study.

CLINICAL SIGNIFICANCE

Based on the results of this study, both the cortical screw and the UHMWPE suture stabilized the tibiotarsal joint at clinically relevant loads. However, when exposed to high loads, the cortical screw provides increased tibiotarsal stability. Comparative data need to be collected prior to widespread use of UHMWPE sutures in clinical cases.

In vivo three-dimensional isometry analysis of suture attachment sites for extracapsular suture stabilization of the canine stifle

BACKGROUND

The study aimed to perform isometry analysis of a selection of suture attachment points for extracapsular stabilization with three-dimensional (3D) measurements and normal gait kinematics of the stifle joint.

METHODS

Thirteen client-owned dogs were recruited. Fluoroscopic images of the stifle during treadmill walking and computed tomography of the same joint were acquired. Stifle kinematics were reconstructed using 3D model-based fluoroscopic analysis. Variability of the distance between the femoral and tibial attachment sites across gait cycles was evaluated. The maximum length variation (MLV) and maximum length percent variation (MLPV) were quantified and used to determine the level of isometry of the attachment site combinations.

RESULTS

A selection of combinations with lower mean MLV (<2.5 mm) or MLPV (<8%) was identified from 315 combinations, and all the combinations involved femoral attachment sites near the distal pole of the lateral fabella. The combinations also involving tibial attachment sites near the proximal tibial crest showed improved isometry, with an MLPV < 6%.

CONCLUSION

Combinations using attachment sites around the distal pole of the lateral fabella and proximal tibial crest or caudal to the long digit extensor groove appeared to have improved isometry.

Femorotibial joint kinematics in nine dogs treated with lateral suture stabilization for complete cranial cruciate ligament rupture

OBJECTIVE

To quantify 3-D femorotibial joint kinematics during ambulation in dogs with cranial cruciate ligament (CCL) rupture treated with lateral fabellotibial suture stabilization (LFTS).

ANIMALS

9 adult dogs (body weight, 15 to 35 kg [33 to 77 lb]) with unilateral complete CCL rupture.

PROCEDURES

Digital 3-D bone models of the femur and fabellae and tibia and fibula were created from CT scans. Lateral fluoroscopic images of stifle joints were collected during treadmill walking before surgery and 6 months after LFTS. The LFTS was performed with nylon leader material secured with knots. Gait cycles were analyzed with a 3-D to 2-D image registration process. Femorotibial joint kinematics (craniocaudal translation, internal-external rotation, and flexion and extension angles) were compared among CCL-deficient stifle joints before LFTS, CCL-deficient stifle joints 6 months after LFTS, and unaffected contralateral (control) stifle joints. Owners and veterinarians subjectively assessed lameness by use of a visual analog scale and gait examination, respectively, at each time point.

RESULTS

At midstance phase, medial cranial tibial translation decreased from 9.3 mm before LFTS to 7.6 mm after LFTS but remained increased when compared with control stifle joint values. Following LFTS, axial rotation and stifle joint flexion and extension angles were not significantly different from control stifle joints. On the owner survey, the median walking lameness score improved from 9.3 of 10 before surgery to 0.3 after surgery. On gait examination, median walking lameness score improved from 2 of 4 before surgery to 0 after surgery.

CONCLUSIONS AND CLINICAL RELEVANCE

Stifle joint instability was only slightly mitigated at 6 months following LFTS performed with knotted nylon leader material in medium to large dogs with CCL rupture, despite improvement in lameness.

Effects of perioperative saphenous and sciatic nerve blocks, lumbosacral epidural or morphine-lidocaine-ketamine infusion on postoperative pain and sedation in dogs undergoing tibial plateau leveling osteotomy

OBJECTIVE

To compare the quality of postoperative analgesia and sedation after preoperative saphenous and sciatic nerve blockade, preoperative lumbosacral epidural injection and perioperative intravenous (IV) morphine, lidocaine and ketamine infusions in dogs undergoing stifle arthroscopy and tibial plateau leveling osteotomy (TPLO) under general anesthesia.

STUDY DESIGN

Prospective, blinded, randomized, clinical comparison study.

ANIMALS

A total of 45 dogs weighing 33.9 (15.9-56.7) kg and aged 5.2 (1.0-12.0) years, mean (range), undergoing elective unilateral TPLO for spontaneous cranial cruciate ligament rupture.

METHODS

Client-owned dogs were enrolled. Dogs were randomly assigned to one of three groups: group MLK, perioperative IV morphine, lidocaine and ketamine infusion; group EPID, lumbosacral epidural with ropivacaine and morphine; or group SSNB, saphenous and sciatic nerve blockade with ropivacaine. Routine stifle arthroscopy followed by TPLO surgery was performed. Sedation and pain scores were assessed at 0, 2, 4, 8 and 24 hours following extubation. Rescue analgesia was administered as prescribed by Glasgow composite pain score-short form score >5.

RESULTS

Sedation scores for MLK were higher than EPID and SSNB. Pain scores for SSNB were lower than those for EPID and MLK. No significant differences were found in anesthesia duration or surgery duration among groups. No dogs required rescue analgesia.

CONCLUSIONS AND CLINICAL RELEVANCE

Although analgesia was adequate in all groups, the best combination of analgesia without increased sedation was recorded for SSNB.

Effect of stifle flexion on the position of the cranial tibial artery relative to the proximal tibia in dogs

OBJECTIVE

To determine the effect of stifle flexion on the proximity of the cranial tibial artery to the proximal tibia in canine stifles with an intact or transected cranial cruciate ligament (CCL).

STUDY DESIGN

Ex vivo randomized blinded computed tomographic angiographic study.

SAMPLE POPULATION

Fifteen pelvic limbs from eight greyhound cadavers.

METHODS

The femoral artery and vein were cannulated and injected with 10 mL of iohexol. Each limb was placed in lateral recumbency on an acrylic sheet with predrawn femoral and tibial lines representing angles of stifle extension. Computed tomography was performed before (limbs 1-15) and after (limbs 10-15) CCL transection. The shortest distance between the cranial tibial artery and proximal tibia (dCrTA-PT) was measured at a distance of one patellar length from medial intercondylar tubercle.

RESULTS

Median dCrTA-PT in intact specimens at 70°, 90°, 110°, and 135° was 2.04, 2.05, 2.28, and 2.51 mm, respectively (P = .008). Pairwise comparisons identified a difference between 70° and 135° (P = .007). Mean dCrTA-PT in transected specimens at 70°, 90°, 110°, and 135° was 2.60, 2.57, 2.90, and 2.79 mm, respectively (P = .208). Median overall dCrTA-PT was 2.24 mm in intact specimens (limbs 1-15, all four angles of extension combined) and 2.76 mm in transected specimens (limbs 10-15, all angles combined; P = .01).

CONCLUSION

Flexion of the stifle resulted in a negligible decrease in dCrTA-PT in intact specimens but had no effect in CCL transected stifles.

CLINICAL SIGNIFICANCE

The angle of stifle extension does not appear to have any clinically significant effect on the proximity of cranial tibial artery to the proximal tibia.

Disease-related and overall survival in dogs with cranial cruciate ligament disease, a historical cohort study

OBJECTIVE

To analyse the effect of treatment method and other risk factors on survival in dogs with cranial cruciate ligament disease (CCLD).

METHODS

A historical cohort study of 333 dogs presenting with CCLD at two University Hospitals (2011-2016) was performed. Signalment, history, treatment and follow-up details were retrieved from medical records, dog owners and referring veterinarians. Treatment groups were defined; conservative or surgical with either lateral fabellotibial suture (LFS) or osteotomy procedures. Multivariable Cox proportional hazards models were applied to evaluate risk factors for disease-related and overall survival.

RESULTS

Sixty-five dogs were conservatively managed, 125 treated with LFS and 143 with osteotomy techniques. At follow-up (autumn 2018), 164 dogs (49.3 %) were alive and 169 (50.7 %) were dead. Both final Cox proportional hazards models included variables for treatment, age, weight and hospital. In addition, the final disease-related model included a variable for orthopaedic comorbidity, while non-orthopaedic comorbidities and a time-varying effect for age on a linear scale were included in the overall survival model. Treatment method was found to have an effect on both disease-related and overall survival and surgical treatment was associated with a lower hazard than conservative treatment.

CONCLUSION

Survival in dogs with CCLD is influenced by treatment strategy, comorbidities, age and weight.

Modified cranial closing wedge osteotomy to treat cranial cruciate ligament deficient stifles with excessive tibial plateau angles: Complications, owner satisfaction, and midterm to long-term outcomes

OBJECTIVE

To report midterm to long-term outcomes of dogs with cranial cruciate ligament (CCL) rupture and excessive tibial plateau angles (TPA) treated with a modified cranial closing wedge osteotomy (m-CCWO).

STUDY DESIGN

Retrospective case series.

STUDY POPULATION

Dogs (n = 21) with CCL rupture and excessive TPA treated with m-CCWO (n = 28).

METHODS

Medical records, midterm and long-term follow-up radiographic examination records, Canine Orthopedic Index data, and owner surveys were reviewed to determine functional outcomes, owner satisfaction, and complications associated with the technique.

RESULTS

Tibial plateau angle decreased from 42.3° ± 4.8° preoperatively to 4.8° ± 3.3° after m-CCWO. No catastrophic complications occurred, while major and minor complications occurred in three of 28 and six of 28 stifles, respectively. Canine Orthopedic Index scores and owner surveys were available in 16 of 21 dogs at a median of 608 days postoperatively (range 279-1225). Functional midterm or long-term outcomes for these dogs treated with m-CCWO were excellent in eight dogs, acceptable in seven dogs, and unacceptable in one dog. Progression of osteoarthritis was noted on all midterm and long-term follow-up radiographs. All owners but one were satisfied.

CONCLUSION

Modified cranial closing wedge osteotomy was associated with an acceptable morbidity and resulted in satisfactory functional outcomes in most dogs of this series.

CLINICAL SIGNIFICANCE

Modified cranial closing wedge osteotomy should be considered as an alternative to treat CCL rupture in dogs with excessive TPA.

Fortetropin inhibits disuse muscle atrophy in dogs after tibial plateau leveling osteotomy

Objective

To determine if a commercial myostatin reducer (Fortetropin®) would inhibit disuse muscle atrophy in dogs after a tibial plateau leveling osteotomy.

Design

A prospective randomized, double-blinded, placebo-controlled clinical trial.

Animals

One hundred client-owned dogs presenting for surgical correction of cranial cruciate ligament rupture by tibial plateau leveling osteotomy.

Procedures

Patients were randomly assigned into the Fortetropin® or placebo group and clients were instructed to add the assigned supplement to the dog’s normal diet once daily for twelve weeks. Enrolled patients had ultrasound measurements of muscle thickness, tape measure measurements of thigh circumference, serum myostatin level assays, and static stance analysis evaluated at weeks 0, 8, and 12.

Results

From week 0 to week 8, there was no change for thigh circumference in the Fortetropin® group for the affected limb (-0.54cm, P = 0.31), but a significant decrease in thigh circumference for the placebo group (-1.21cm, P = 0.03). There was no significant change in serum myostatin levels of dogs in the Fortetropin® group at any time point (P>0.05), while there was a significant rise of serum myostatin levels of dogs in placebo group during the period of forced exercise restriction (week 0 to week 8; +2,892 pg/ml, P = 0.02). The percent of body weight supported by the affected limb increased in dogs treated with Fortetropin® (+7.0%, P<0.01) and the placebo group (+4.9%, P<0.01) at the end of the period of forced exercise restriction. The difference in weight bearing between the Fortetropin® and placebo groups was not statistically significant (P = 0.10).

Conclusion

Dogs receiving Fortetropin® had a similar increase in stance force on the affected limb, no significant increase in serum myostatin levels, and no significant reduction in thigh circumference at the end of the period of forced exercise restriction compared to the placebo. These findings support the feeding of Fortetropin® to prevent disuse muscle atrophy in canine patients undergoing a tibial plateau leveling osteotomy.

Ex vivo mechanical properties of a 2.5-mm bone anchor for treatment of cranial cruciate ligament rupture in toy breed dogs

OBJECTIVE

To determine the mechanical pull-out properties of a 2.5-mm bone anchor implanted in ex vivo femurs of toy breed dogs and to determine whether there is a difference between knotted and knotless configurations.

STUDY DESIGN

Experimental study.

SAMPLE POPULATION

Eight paired harvested femurs.

METHODS

Femurs were assigned to knotted or knotless configuration. Equal numbers of right and left femurs were tested. The caudolateral femoral condyle at the distal pole of the lateral fabella (F2 site) was drilled. The assigned configuration with braided suture combined with the bone anchor was implanted into the F2 site. Each configuration was positioned into a mechanical testing machine to measure yield load, load at 3-mm displacement, ultimate load, stiffness, and mode of failure at the beginning of the canine standing phase angle (150°).

RESULTS

Mean ultimate load was 100.14 and 88.69 N (P = .798), mean yield load was 59.72 and 55.85 N (P = .708), load at 3-mm displacement was 46.72 and 43.33 N (P = .656), and stiffness was calculated to be 43.06 and 47.09 N/mm (P = .548) for knotted and knotless configurations, respectively. Mode of failure occurred primarily by anchor pull-out.

CONCLUSION

The bone anchor withstood deformation at the estimated forces applied on the native cranial cruciate ligament (CCL) of toy breed dogs in both configurations.

CLINICAL SIGNIFICANCE

This bone anchor may constitute a useful alternative for stabilization of the CCL deficient stifle in toy breed dogs. However, before it can be recommended for widespread use in dogs, closely monitored clinical trials must be conducted to assess outcome and complications associated with this implant.

Tibial Plateau Leveling Osteotomy for Cranial Cruciate Ligament Rupture in Canines: Patient Selection and Reported Outcomes

Cranial cruciate ligament (CCL) rupture is one of the most common causes of pelvic limb lameness in dogs. In a CCL deficient stifle, joint lameness develops from cranial tibial translation in relation to the distal femoral condyles. The tibial plateau leveling osteotomy (TPLO) is a well-described surgical procedure that neutralizes tibiofemoral shear force by altering the tibial plateau via a proximal tibial osteotomy, and subsequently restores normal limb function. Current literature for the TPLO was reviewed and used to describe the optimal patient selection and to report clinical outcome with the TPLO in comparison to other surgical options for CCL rupture. The clinical outcomes reported to date, particularly those utilizing objective outcome data, support the TPLO as being able to consistently return dogs to normal limb function with a low risk for long-term morbidity. The TPLO procedure was found to be widely applicable to dogs ranging from small breed to large and giant breed, and does not appear to have some of the limitations that exist with alternative surgical options. This review concludes that the TPLO is an excellent treatment option for any dog with CCL rupture due to the excellent long-term outcome and high rate of owner satisfaction previously reported. Despite these conclusions, it is important to remember that treatment selection for CCL rupture remains dependent on multiple considerations including patient factors, surgeon experience, and costs.

Genetic mapping of distal femoral, stifle, and tibial radiographic morphology in dogs with cranial cruciate ligament disease

Cranial cruciate ligament disease (CCLD) is a complex trait. Ten measurements were made on orthogonal distal pelvic limb radiographs of 161 pure and mixed breed dogs with, and 55 without, cranial cruciate partial or complete ligament rupture. Dogs with CCLD had significantly smaller infrapatellar fat pad width, higher average tibial plateau angle, and were heavier than control dogs. The first PC weightings captured the overall size of the dog’s stifle and PC2 weightings reflected an increasing tibial plateau angle coupled with a smaller fat pad width. Of these dogs, 175 were genotyped, and 144,509 polymorphisms were used in a genome-wide association study with both a mixed linear and a multi-locus model. For both models, significant (p_genome <3.46×10⁻⁷ for the mixed and< 6.9x10^-8 for the multilocus model) associations were found for PC1, tibial diaphyseal length and width, fat pad base length, and femoral and tibial condyle width at LCORL, a known body size-regulating locus. Other body size loci with significant associations were growth hormone 1 (GH1), which was associated with the length of the fat pad base and the width of the tibial diaphysis, and a region on CFAX near IRS4 and ACSL4 in the multilocus model. The tibial plateau angle was associated significantly with a locus on CFA10 in the linear mixed model with nearest candidate genes BET1 and MYH9 and on CFA08 near candidate genes WDHD1 and GCH1. MYH9 has a major role in osteoclastogenesis. Our study indicated that tibial plateau slope is associated with CCLD and a compressed infrapatellar fat pad, a surrogate for stifle osteoarthritis. Because of the association between tibial plateau slope and CCLD, and pending independent validation, these candidate genes for tibial plateau slope may be tested in breeds susceptible to CCLD before they develop disease or are bred.

Comparison of tension band wiring and other tibial tuberosity advancement techniques for cranial cruciate ligament repair: an experimental study

BACKGROUND

Cranial cruciate ligament (CCL) rupture is one of the most common causes of limb lameness in dogs. Surgical techniques based on tibial osteotomies such as tibial plateau leveling osteotomy and tibial tuberosity advancement are used to eliminate dynamic thrust. Tibial tuberosity advancement (TTA) uses an osteotomy fixated by cage, plates, forks and screws to change the relationship of the patellar tendon and tibial plateau angle. Tension band wiring technique is one of the most common surgical methods used to treat a tension fracture and remains the gold standard for the treatment of tibial tuberosity fractures. In this study, we compared experimentally the biomechanical effect of application of tension band wiring compared to other techniques for the fixation of the TTA osteotomy. The techniques compared to are standard commercially available systems for TTA fixation.

RESULTS

Tension band wiring (TBW) presented the higher resistance to failure compared to all the other surgical procedures, with the highest values found in the TBW group with 1.47 ± 0.07 N and the lowest in the TTA cage (0.82 ± 0.08) and TTA-2 (0.85 ± 0.06) groups with statistically significant differences in all cases (P < 0.001). TTA rapid and TTA plate groups exhibited a similar strength, and same happened between TTA-2 and TTA cage groups. All the other comparisons by pair were significantly different with P < 0.001.

CONCLUSIONS

Results suggest that fixating the osteotomy with tension band wiring increases the strength of the fixation and decrease the risk of implant failure. Further clinical studies are needed to demonstrate in vivo reliability and to test different variables such as size and weight of dogs. These results could have important clinical implications in the treatment of CCL ruptures.

Relationship between the stage of osteoarthritis before and six months after tibial tuberosity advancement procedure in dogs

The present retrospective study evaluated the progression of osteoarthritis in stifle joints based on the radiographic grade of osteoarthritis (OA) scored in dogs with cranial cruciate ligament rupture. The aim of the study was to search for a correlation between the stage of radiographic osteoarthritis prior to surgery and the osteoarthritis progression occurring after the tibial tuberosity advancement (TTA) procedure. It was hypothesized that the procedure carried out in dogs in the early stages of OA could reduce the OA changes. A total of 190 X-ray images obtained from the medical records of 38 dogs were evaluated. The radiographic signs of osteoarthritis of 38 stifle joints were scored from 0 to 3 in 10 specific anatomic locations. The radiographs were divided into 4 groups based on the global scores: A) no-OA, B) mild-OA, C) moderate-OA, D) severe-OA; they were assessed prior to surgery, and 1, 2, 3 and 6 months post-operatively (T0, T1, T2, T3 and T6). There were no differences in osteoarthritis progression in Groups A and C at any time. Osteoarthritis changes from T0 to T6 were statistically significant in Group B. The OA changes in the anatomic locations were investigated. The most common anatomic sites for OA changes were the patella apex, the proximal and distal trochlear ridges, and the caudal aspect of the tibial plateau assessed before surgery. After surgery, the score increased in the first three locations in 10, 9 and 11 joints, respectively; instead, the progression of osteoarthritis in the caudal aspect of the tibial plateau occurred in 23 out of 38 stifle joints. The results indicated that the TTA procedure could be effective in slowing down the OA progression when carried out in the absence of or in the early stages of disease. Therefore, an early intervention may be suggested in clinical practice to obtain minimal or no progression 6 months postoperatively.