Complications and outcomes of total hip arthroplasty in dogs with luxoid hip dysplasia: 18 cases (2010-2022).

OBJECTIVE: To describe the complications and outcomes in dogs with luxoid hip dysplasia (LH) undergoing total hip arthroplasty (THA) and compare complication rates with THA in non-LH dogs. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Client-owned dogs (n = 217) undergoing primary THA (n = 238). METHODS: Medical records (2010-2022) of dogs undergoing THA were reviewed, and LH was defined as complete dorsal displacement of the femoral head from the acetabulum on lateral projection radiographs. Major or catastrophic complications, revisions, and outcomes were recorded for all dogs and they were compared between LH and non-LH groups. RESULTS: Eighteen cases met the subcriterion for the LH group and 220 cases met the subcriterion for inclusion in the non-LH group. There were 14 complications in 13/18 dogs with LH; seven were intraoperative (femoral fissure/fracture) and seven were postoperative (dorsal luxation, n = 5; femoral fracture, n = 1; acetabular cup septic loosening, n = 1). Revisions were performed for all LH dogs that encountered complications; satisfactory outcomes were achieved in 12/13 dogs. Overall, LH dogs had a higher risk of developing complications (p < .001), including intraoperative fracture (p < .001) and postoperative dorsal luxation (p = .019) when compared with non-LH dogs. CONCLUSION: Luxoid hip dysplasia was associated with a higher risk of major complications following THA in dogs, specifically intraoperative fissure/fracture and postoperative dorsal luxation. Despite the increased risk, revisions typically yielded satisfactory outcomes. CLINICAL SIGNIFICANCE: Luxoid hip dysplasia is an important risk factor for the development of major complications in dogs undergoing THA.

Caudal pole meniscectomy through an arthroscopic caudomedial portal in dogs: A cadaveric study.

OBJECTIVE: To describe a caudomedial instrumental portal for caudal pole meniscectomy (CPM). STUDY DESIGN: Experimental ex-vivo study. SAMPLE POPULATION: Ten cadaveric hindlimbs of 10 large breed dogs. METHODS: Each hindlimb was used for establishing the caudomedial portal for CPM. The surgical time was recorded. Specimens were disarticulated afterwards, and the completeness of CPM was documented. Iatrogenic injuries to the articular cartilage and the intra- and periarticular structures were assessed. RESULTS: The extent of the CPM (mean ± SD, percentage of the resected medial meniscus) was 29.8 ± 12.9% of the area of the medial meniscus. There were no injuries to the medial collateral ligament or caudal cruciate ligament. The mean iatrogenic articular cartilage injury (IACI) was 3.71 ± 1.78% of the area of the medial meniscus. CONCLUSION: The establishment of a caudomedial portal for CPM in canine cadavers was feasible and allowed to perform a partial caudal pole meniscectomy. CLINICAL SIGNIFICANCE: A caudomedial portal may be considered for CPM in selected cases when caudal tears cannot be accessed through the standard portals.

Computed tomographic measurements of the femoral trochlea in dogs with and without medial patellar luxation.

OBJECTIVES: To determine cutoff values in small (SB) and medium/large (MLB) breed dogs with and without medial patellar luxation (MPL) for identifying abnormal femoral trochlea morphology. STUDY DESIGN: Original research. ANIMALS: A total of 80 computed tomographic (CT) scans from client-owned dogs METHODS: Four groups of 20 dogs were created: (1) control SB, (2) control MLB, (3) MPL-SB, and (4) MPL-MLB. Two authors measured the femoral trochlear groove angle (FTGA), femoral trochlear angle (FTA), and femoral trochlear ridge inclination angle (FTRIA) in two points with CT. ANOVA and ROC-analysis were tested to the control and MPL groups to assess sensitivity, specificity, and cutoff values. Statistical significance was set to p < .05. Intraclass correlation coefficients evaluated the inter-rater agreement. RESULTS: FTGA (± SD) in control SB (128.8° ± 4.7°) and control MLB (119.2° ± 5.6°), was smaller (p < .0001) than in MPL-SB (139.4° ± 4.4°) and MPL-MLB (133.7° ± 5.1°). FTA and FTRIA were decreased (p = .12, p = .23) in MPL-SB (2.1° ± 6.8; -0.3° ± 3.3°) and MPL-MLB (3.8° ± 5.6°; 1.7° ± 4.5°) compared to control SB (0.2° ±4.1; -0.1° ± 2.6°) and control MLB (5.3° ± 2.8°; 3.1° ± 1.3°). Cutoff values for FTGA, FTA, and FTRIA were > 134°, < -5.9°, < -2 ° (SB), and > 128.3°, < -0.4°, < -0.4° (MLB). Sensitivity, specificity, and inter-rater agreement were superior for FTGA than FTA and FTRIA. CONCLUSIONS: Dogs without MPL had a deeper femoral trochlear groove than MPL dogs. SB had a shallower groove than MLB. The measurement of FTA and FTRIA was not reliable. CLINICAL RELEVANCE: A FTGA <134° (SB) and < 128° (MLB) may be considered as a cutoff for trochleoplasty decision-making.

Evaluation of the accuracy and intra- and interobserver reliability of three manual laxity tests for canine cranial cruciate ligament rupture-An ex vivo kinetic and kinematic study.

OBJECTIVES: To investigate the accuracy and intra- and interobserver reliability of the cranial drawer test (CD), tibial compression test (TCT), and the new tibial pivot compression test (TPCT) in an experimental setting resembling acute cranial cruciate ligament rupture (CCLR) and to elucidate the ability to subjectively estimate cranial tibial translation (CTT) during testing. STUDY DESIGN: Experimental ex vivo study. SAMPLE POPULATION: Ten cadaveric hindlimbs of large dogs. METHODS: Kinetic and 3D-kinematic data was collected while three observers performed the tests on each specimen with intact (INTACT) and transected cranial cruciate ligament (CCLD) and compared using three-way repeated-measures ANOVA. Subjectively estimated CTT (SCTT), obtained during a separate round of testing, was compared to kinematic data by Pearson correlation. RESULTS: CTT was significantly higher for CCLD than for INTACT for all tests, resulting in 100% sensitivity and specificity. TPCT induced the highest CTT and internal rotation. Intra- and interobserver agreement of translation was excellent. For rotation and kinetics, agreement was more variable. SCTT strongly correlated with the objectively measured values. CONCLUSION: The CD, TCT and the new TPCT were all accurate and reliable. The high translations and rotations during TPCT are promising, encouraging further development of this test. SCTT was reliable in our experimental setting. CLINICAL SIGNIFICANCE: Veterinary manual laxity tests are accurate and reliable in acute CCLR. The TPCT might have potential for the assessment of subtle and rotational canine stifle instabilities. The high reliability of SCTT implies that grading schemes for stifle laxity, similar to human medicine, could be developed.

Comparative kinetic and kinematic evaluation of TPLO and TPLO combined with extra-articular lateral augmentation: A biomechanical study.

OBJECTIVES: To investigate stifle kinematics and kinetics following TPLO and TPLO combined with an extra-articular lateral augmentation (TPLO-IB) during the tibial compression test (TCT) and the tibial pivot compression test (TPT), applied with an external (eTPT) and an internal moment (iTPT). STUDY DESIGN: Experimental ex vivo study. SAMPLE POPULATION: Ten cadaveric hindlimbs of dogs weighing 23-40 kg. METHODS: 3D-kinematic and kinetic data were collected while performing TCT, eTPT, and iTPT and compared under the conditions (1) normal, (2) CCL deficient, (3) TPLO, and (4) TPLO-IB. Two-way repeated-measures ANOVA was used to examine the effect of test and treatment on kinetic and kinematic data. RESULTS: Mean ± SD preoperative TPA was 24.7° ± 1.7°, postoperative TPA was 5.9° ± 0.7°. During TCT, there was no difference in cranial tibial translation between the intact stifle and after TPLO (p = .17). In contrast, cranial tibial translation was six times larger in TPLO compared to intact when performing eTPT and iTPT (p < .001). Cranial tibial translation with TCT, eTPT and iTPT was not different between intact stifle and TPLO-IB. Intraclass correlation coefficient for eTPT and iTPT after TPLO and TPLO-IB was excellent being 0.93 (0.70-0.99) and 0.91 (0.73-0.99), respectively. CONCLUSION: Whereas TCT is negative after TPLO, instability persists when a rotational moment is combined using eTPT and iTPT. TPLO-IB neutralizes craniocaudal and rotational instability when performing TCT, eTPT, and iTPT.

Modified toggle pin technique combined with prosthetic capsular reconstruction for surgical stabilization of coxofemoral luxation in a Shetland pony.

OBJECTIVE: To describe open reduction and surgical stabilization of a coxofemoral luxation in a pony using a modified toggle pin technique and prosthetic joint capsule reconstruction without osteotomy of the greater trochanter. ANIMAL: A 2-year-old Shetland pony with a bodyweight of 167 kg. STUDY DESIGN: Case report. METHODS: Radiographic examination confirmed craniodorsal luxation of the left coxofemoral joint. An open reduction with the aid of a pulley system was performed. A toggle pin was inserted through a bone tunnel extending from the level of the femoral shaft through the femoral head and the center of the acetabulum for the pin to be positioned on the medial wall of the acetabulum. FiberWire was subsequently passed through the cranial and caudal aspects of the acetabulum as well as a transverse tunnel in the femoral neck in a figure of 8 to facilitate capsular reconstruction. The pony was placed in a sling for 8 weeks and gradually returned to normal activity over 2 months. RESULTS: Postoperative radiographic examination confirmed the position of the femoral head in the acetabulum with the implants in place. On 2-year follow-up the pony was sound at walk and trot. CONCLUSION: A combined intra- and extra-articular stabilization technique for coxofemoral luxation in a pony resulted in successful long-term reduction and excellent outcome.

Ex vivo comparison of lateral plate repairs of experimental oblique ilial fractures in cats.

OBJECTIVE: To determine the biomechanical behavior of different plate systems used for oblique ilial fracture fixation in cats. STUDY DESIGN: Ex vivo biomechanical study. SAMPLE POPULATION: Fifty fresh-frozen feline hemipelvises. METHODS: Standardized simple oblique ilial fractures were created and fixed via lateral plating, using different implant systems (10 fractures in each group) The systems were: (1) the Advanced Locking Plate System (ALPS-5); (2) the Advanced Locking Plate System (ALPS-6.5); (3) the Locking Compression Plate 2.0 (LCP); (4) the FIXIN 1.9-2.5 Series (FIXIN), and (5) the Dynamic Compression Plate 2.0 (DCP). Stepwise sinusoidal cyclic loading was applied until failure (10-mm displacement). The groups were compared with regard to construct stiffness and the number of cycles withstood before 1-, 2-, 5-, and 10-mm displacement. RESULTS: Bending stiffness was lower in ALPS-5 than in other specimens (P < .05). The ALPS-6.5 specimens withstood more cycles (P < .05) before 2-, 5-, and 10-mm displacement than the ALPS-5 and DCP specimens . The LCP and FIXIN specimens endured more cycles than DCP specimens before displaying 5- and 10-mm displacement (P < .05). The ALPS-6.5, FIXIN, and LCP specimens endured higher loads before failure than the DCP specimens (P < .05). Screw loosening occurred in all nonlocking specimens, and bone slicing occurred in all locking specimens. CONCLUSION: The DCP and ALPS-5 constructs are less resistant to cyclic loading. Failure in nonlocking specimens involved screw loosening. It involved bone slicing in locking specimens. CLINICAL SIGNIFICANCE: Both the plate size and the plate-screw interface are key to lateral plating success in cases of feline ilial fractures. The use of locking plates reduces the risk of the screw loosening in such cases.

Three-dimensional volume rendering planning, surgical treatment, and clinical outcomes for femoral and tibial detorsional osteotomies in dogs.

OBJECTIVES: To describe a computed tomographic (CT) methodology for planning the correction of femoral and tibial torsion and report the clinical outcomes after femoral (FDO) and tibial (TDO) detorsional osteotomy in dogs affected by torsion malalignment and patellar luxation (PL). STUDY DESIGN: Multicenter retrospective study. ANIMALS: Eighteen client-owned dogs. METHODS: Dogs underwent CT to measure femoral (FTA) and tibial torsion angle (TTA). Abnormal femoral external torsion was defined when FTA <20°, abnormal femoral internal torsion if FTA >35°; abnormal tibial external torsion was defined when TTA < -10°, and abnormal tibial internal torsion when TTA >2°. The cortical arch length (CAL) was measured with CT and used intraoperatively to determine the magnitude of correction. The medical records and radiographs were reviewed and used to report clinical and radiographic outcomes. Radiographs were reviewed to evaluate postoperative limb alignment, patellar position, and bone healing. RESULTS: Twenty-two detorsional osteotomies were performed. Mean preoperative FTA was 14° for medial-PL and 45.2° for lateral-PL. Mean preoperative TTA was 11° for medial-PL. Physiological patellar tracking was restored in 22/22 of cases. CAL measurement allowed for correction of abnormal torsion in 19/22 of cases. Seventeen out 18 dogs had full or acceptable functional outcome. The median radiographic follow-up was 3 months. Major complications occurred in 2/22 cases, which suffered an iatrogenic abnormal femoral internal torsion and a persistent hindlimb lameness. CONCLUSIONS: CAL can be measured with CT and used intraoperatively to guide the correction of abnormal torsion in dogs. CLINICAL RELEVANCE: Abnormal femoral and tibial torsion are predisposing factors for PL. A higher complication rate is expected when FDO and TDO are performed in the same hindlimb.

A review of minimally invasive fracture stabilization in dogs and cats.

OBJECTIVE: To summarize and discuss peer-reviewed studies on minimally invasive osteosynthesis (MIO) of long bone, physeal, and articular fractures in dogs and cats. STUDY DESIGN: Invited review. METHODS: A critique of literature was performed to assess MIO feasibility, outcomes, and complications through PubMed, Scopus, and CAB abstracts research databases (2000-2020). RESULTS: More than 40 MIO articles have been published in the last 15 years, but most studies had small numbers, lacked control groups, and used limited outcome measures. Studies generally showed that MIO was feasible in dogs and cats with low complication rates. The current evidence does not demonstrate superior bone healing or functional outcomes with MIO when compared to standard methods. Although treatment principles, case selection, and techniques varied depending on the anatomical location, there were no salient differences in complication rates among long bones, physeal, and articular fractures treated by MIO. CONCLUSION: The current available evidence and the personal experience of the authors support MIO as a promising fracture management modality. MIO can yield excellent outcomes when applied in carefully selected cases, performed by surgeons experienced in the technique. We cannot, however, conclude that MIO is superior to open fracture stabilization based on the available evidence in veterinary literature. Randomized controlled studies are warranted to prospectively compare MIO with other osteosynthesis techniques and thereby validate its role in fracture management for dogs and cats.

A three-dimensional computed tomographic volume rendering methodology to measure the tibial torsion angle in dogs.

OBJECTIVE: To describe a three-dimensional (3D) computed tomographic (CT) methodology to measure the tibial torsion angle (TTa) and to evaluate intrarater and interrater agreements and accuracy through comparison with anatomic measurements. STUDY DESIGN: Ex vivo cadaveric study. SAMPLE POPULATION: Thirty-six tibiae from 18 dogs. METHODS: Tibial torsion angle of each tibia was measured by using two CT techniques (axial and 3D volume rendering) by three raters who blindly measured TTa in duplicate. A semitransparent bone filter was used to enhance the visibility of the target anatomical landmarks for the 3D volume rendering CT technique. Tibial torsion angle was also quantitated in tibial specimens. Intrarater and interrater agreements were analyzed by using intraclass coefficients (ICC). Accuracy was evaluated by using adjusted R2 coefficients (R2 > 80% was considered acceptable). RESULTS: The 3D volume rendering CT technique had excellent intrarater and interrater agreements (ICC > 0.94) and an R2 value of 97%. The axial CT technique had good to excellent intrarater and interrater agreements (0.8 < ICC < 0.95) and an R2 of 86%. No difference was found between axial and 3D CT techniques. A mean internal TT angle of approximately -6° was found with CT and anatomic measurements. CONCLUSION: The 3D volume rendering and axial CT techniques were precise and accurate for measuring TTa in dogs unaffected by patellar luxation. CLINICAL RELEVANCE: Combining 3D bone manipulation with application of a semitransparent filter allows simultaneous visualization of anatomic landmarks, which may facilitate the evaluation of complex bone deformations. Internal tibial torsion may be present in nonchondrodystrophic dogs without patella luxation.

Biomechanical comparison of ex vivo lumbar vertebral fracture luxations stabilized with tension band or polymethylmethacrylate in cats.

OBJECTIVE: To evaluate spinal stabilization with tension band stabilization (TS) in cats compared to screw and polymethylmethacrylate fixation (SP). STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Sixteen feline thoracolumbar spinal specimens. METHODS: The intact specimens were mounted in a six-degree-of-freedom biaxial testing machine for nondestructive testing to obtain the neutral zones (NZ) and range of motion (ROM) in flexion and extension. Thereafter, nondestructive testing was consecutively performed after destabilization by disc fenestration and partial L1 corpectomy and after treatment with either TS or SP. Load to failure was compared after surgical treatment in flexion. Significance was assessed by Student's t test or Wilcoxon signed-rank test. RESULTS: Range of motion was 26.4° ± 2.2° in TS constructs and 13.4° ± 2.1° in SP constructs (P = .0005). When flexion and extension were analyzed separately, no difference was found for ROM in flexion (SP, 7.0° ± 3.7°; TS, 8.3° ± 2.1°; P = .38). In extension, the mean displacement was 6.4° ± 2.7° and 18.1° ± 5.1° in SP and TS constructs, respectively (P = .0001). Neutral zone was 2.9° ± 0.6° and 7.5° ± 0.8° for the SP and TS groups, respectively (P = .0003). Screw and polymethylmethacrylate fixation constructs were two times stiffer (P = .045). CONCLUSION: Tension band stabilization provided stability comparable to SP in flexion. In extension, ROM of SP constructs was half that of TS constructs. The mode of failure of TS was related to the limited dorsal bone stock of feline lumbar vertebrae. CLINICAL SIGNIFICANCE: Surgeons should be aware of the limited stability in extension provided by TS when it is used to stabilize thoracolumbar spinal injuries. Our results provide evidence to justify additional studies to clarify the type of fractures amenable to TS.

Influence of a customized three-dimensionally printed drill guide on the accuracy of pedicle screw placement in lumbosacral vertebrae: An ex vivo study.

OBJECTIVE: To compare the accuracy of pedicle screw insertion (PSI) into canine lumbosacral vertebrae with custom-made three-dimensionally (3D)-printed drill guides or freehand insertion. STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Nineteen canine lumbosacral specimens. METHODS: Drill guides for PSI were designed on the basis of safe screw insertion trajectories by using preoperative computed tomography (CT) and produced by 3D printing of templates. Right and left sides of the specimens were randomly allocated to two groups; 4-mm pedicle screws were inserted in L5-L6 and L7-S1 spinal segments either freehand (control group) or with custom-made drill guides (guide group). Sixty-six screws were inserted with each method. Insertion angles (α, ß), bone stock, and vertebral canal breach were assessed according to postoperative CT. χ2 Tests were used to compare vertebral canal breach between groups and vertebrae. RESULTS: Breaches in the vertebral canal were less common (P < .001) when screws were placed with a guide in the guide group (9/66, 14%) than without a guide (30/66, 45%). The rate of vertebral canal breach differed at L5 (P = .021) but not at L6 (P = .05), L7 (P = .075) or S1 (P = .658). The angle of insertion (α) did not differ between specimens with and without breaches (guide, P = .068; control, P = .394). CONCLUSION: The use of a customized 3D-printed guide generally improved the accuracy of PSI in canine lumbosacral vertebrae, although statistical significance was reached only at L5. CLINICAL SIGNIFICANCE: The use of customized drill guides may be considered as an alternative to freehand PSI in the lumbosacral area, especially for L5-L6 vertebrae.

Fundamental principles of rehabilitation and musculoskeletal tissue healing.

OBJECTIVE: To review fundamental principles of tissue healing and physical rehabilitation as they apply to dogs recovering from cranial cruciate ligament (CCL) surgery. STUDY DESIGN: Invited Review. SAMPLE POPULATION: None. METHODS: A multidisciplinary group of specialists in small animal surgery, rehabilitation/sports medicine, and human physical and occupational therapy reviewed the currently available evidence for rehabilitation post-CCL surgery. Because current evidence is limited, this group proposes guidelines for rehabilitation after CCL surgery based on the fundamental principles of tissue healing and physical therapy. RESULTS: This Review proposes four fundamental principles of small animal physical rehabilitation based on the foundations of tissue healing and patient-centric and goal-oriented therapy. Postoperative rehabilitation programs should be designed such that patient progress is based on individual assessment according to the degree of tissue healing, strength, and achievement of functional goals. Therapists must fully understand phases of tissue healing, reassess the patient frequently, and use clinical reasoning skills to progress treatment appropriately for the individual patient. CONCLUSION: Until more robust evidence is available to guide treatment protocols, fundamental principles of rehabilitation should ideally be adhered to when providing rehabilitation, including after CCL surgery. CLINICAL SIGNIFICANCE: While this Review specifically addresses post-CCL surgery rehabilitation, these fundamental principles should be applied broadly to animals enrolled in rehabilitation programs.

The effect of tibial plateau leveling osteotomy on patellofemoral kinematics in dogs: An in vivo study.

OBJECTIVE: To quantitatively evaluate patellofemoral (PF) kinematics during walking in dogs with cranial cruciate ligament (CrCL) deficiency treated by tibial plateau leveling osteotomy (TPLO). STUDY DESIGN: Longitudinal observational study. ANIMALS: Dogs with unilateral CrCL deficiency treated by TPLO (n = 10). METHODS: Horizontal beam fluoroscopic images of the stifles during treadmill walking were acquired 6 months after TPLO. Computed tomography was performed, and digitized bone models of both femurs and patellae were created. These digital models were superimposed over the fluoroscopic images with shape-matching software, and sagittal plane PF kinematics for TPLO-treated and normal contralateral stifles were calculated. Patellofemoral kinematics were described according to phase of gait cycle as well as relative to femorotibial flexion angle. RESULTS: In TPLO-treated stifles, there was an approximately 1-mm increase in cranial displacement of the patella (P < .05) compared with the normal stifle at equivalent femorotibial flexion angles between 120° and 140° and predominately during the stance phase. Proximal-distal translation and patellar flexion angle were mostly unaffected by TPLO when they were assessed according to either equivalent phase of gait cycle or femorotibial flexion angles. CONCLUSION: In vivo PF kinematics in TPLO-treated stifles were subtly different from normal, characterized by slight cranial shifting of the patella relative to the trochlear groove. CLINICAL SIGNIFICANCE: The clinical significance of these results remains unknown. These results may provide further understanding into extensor mechanism abnormalities associated with TPLO.

Predictors of comorbidities and mortality in cats with pelvic fractures.

OBJECTIVE: To characterize and evaluate risk factors for comorbidities and death of cats with pelvic fractures. STUDY DESIGN: Retrospective case study. ANIMALS: Cats (n = 280). METHODS: Medical records were reviewed for cats in which pelvic fractures had been diagnosed (January 2003 to November 2016). Retrieved data included signalment, mechanism of injury, clinical findings, diagnostic imaging investigations, type and number of concurrent injuries based on anatomical location, type of therapy, and survival. Pelvic fractures were classified according to location and severity. Descriptive statistics were performed, and logistic regression models were constructed to examine associations between risk factors and outcome. RESULTS: Cases consisted of 280 cats with no (9%), unilateral (43%), and bilateral (48%) involvement of the weight-bearing axis. Sacral fractures were found in 12% of cats. Surgical treatment and mortality rates increased progressively with the severity of the pelvic fractures (P < .001). Mean number of concurrent body regions injured was 2.4 ± 1.2 and was associated with mortality (P < .01). Twenty percent of cats did not survive to discharge. Cats with neurologic injuries were more likely not to survive (P = .02). CONCLUSION: Concurrent injuries to at least one body region, especially the abdomen and thorax, were observed in cats sustaining pelvic fractures. Mortality was associated with increased severity of the fractures, neurologic injuries, and increased number of concurrent injuries. CLINICAL SIGNIFICANCE: Concurrent injuries are common in cats with pelvic fractures, and comorbidities may be associated with mortality.

Biomechanical comparison of knotted and knotless stabilization techniques of the tarsal medial collateral ligament in cats: A cadaveric study.

OBJECTIVE: To compare mechanical properties of intact feline medial collateral ligaments and three techniques for treatment of feline medial tarsal instability. STUDY DESIGN: Controlled laboratory study. SAMPLE POPULATION: Forty-eight normal, adult feline tarsi. METHODS: Three repairs were tested: a bone tunnel with polypropylene (PP) suture, a bone tunnel with polyethylene (PE) cord, and a knotless anchor technique with PE cord. A cyclic (6-N preload; 5-N amplitude; 2-Hz frequency) tensile test (600 cycles) was performed on feline tarsi with either the long or the short medial tarsal ligament intact, with each reconstruction technique followed by a single-cycle load-to-failure test (0.5 mm/s) with a failure point at 2 mm of displacement. Total elongation, peak-to-peak elongation, stiffness, and maximum load to failure point were compared with the intact condition. RESULTS: No differences in stiffness, total elongation, or peak-to-peak elongation were found between specimens repaired with the knotless technique and intact controls (P > .04), whereas tarsi repaired with the tunnel technique and PP were weaker (P < .008). Total and conditioning elongation were greater after tunnel reconstruction with PP than after knotless reconstruction (P = .005). Mean load to 2 mm of displacement tended (P = .03) to be higher after knotless than after knotted PP repairs and did not differ (P = .47) between tarsi repaired with the tunnel or anchor repairs with PE. CONCLUSION: The mechanical properties of intact tarsi were superior to those of tarsi repaired with tunnel techniques and PP but were similar to those of tarsi repaired with knotless techniques with PE. CLINICAL SIGNIFICANCE: Feline tarsal stabilization with the knotless technique for tarsal medial collateral ligament insufficiency may reduce the requirement for or duration of postoperative coaptation.

Femorotibial kinematics in dogs treated with tibial plateau leveling osteotomy for cranial cruciate ligament insufficiency: An in vivo fluoroscopic analysis during walking.

OBJECTIVE: To determine the ability of tibial plateau leveling osteotomy (TPLO) to address abnormal femorotibial kinematics caused by cranial cruciate ligament (CCL) rupture during walking in dogs. STUDY DESIGN: Prospective, clinical. ANIMALS: Sixteen dogs (20-40 kg) with unilateral complete CCL rupture. METHODS: Lateral view fluoroscopy was performed during treadmill walking preoperatively and 6 months after TPLO. Digital three-dimensional (3D) models of the femora and tibiae were created from computed tomographic (CT) images. Gait cycles were analyzed by using a 3D-to-2D image registration process. Craniocaudal translation, internal/external rotation, and flexion/extension of the femorotibial joint were compared between preoperative and 6-month postoperative time points for the affected stifle and 6-month postoperative unaffected contralateral (control) stifles. RESULTS: In the overall population, CCL rupture resulted in 10 ± 2.2 mm (mean ± SD) cranial tibial translation at midstance phase, which was converted to 2.1 ± 4.3 mm caudal tibial translation after TPLO. However, five of 16 TPLO-treated stifles had 4.1 ± 0.3 mm of cranial tibial subluxation during mid-to-late stance phase, whereas 10 of 16 TPLO-treated stifles had 4.3 ± 0.4 mm of caudal tibial subluxation throughout the gait cycle. Overall, postoperative axial rotational and flexion/extension patterns were not different from control, but stifles with caudal tibial subluxation had more external tibial rotation during mid-to-late stance phase compared with stifles with cranial tibial subluxation. CONCLUSION: TPLO mitigated abnormal femorotibial kinematics but did not restore kinematics to control values in 15 of 16 dogs during walking. CLINICAL SIGNIFICANCE: Tibial plateau leveling osteotomy reduces cranial tibial subluxation during walking, but persistent instability is common.

Recommendations for rehabilitation after surgical treatment of cranial cruciate ligament disease in dogs: A 2017 survey of veterinary practitioners.

OBJECTIVE: To report current recommendations made by veterinarians for rehabilitation after surgical treatment of cranial cruciate ligament (CrCL) disease. STUDY DESIGN: Anonymized electronic survey. SAMPLE POPULATION: Veterinarians performing CrCL stabilization. METHODS: An electronic survey was created to collect information on general attitudes toward postoperative rehabilitation and recommendations regarding therapeutic modalities and bandaging. Quantitative data are reported by descriptive statistical analysis, percentage of responses, or mean (±SD). The recommendations for postoperative bandaging beyond 24 hours and for postoperative rehabilitation after extracapsular stabilization compared with after tibial osteotomy were tested by using Cochran-Mantel-Haenszel tests, with P < .05 considered statistically significant. RESULTS: The data analysis included 376 responses (13% response rate). Most (71%) respondents consistently recommended postoperative rehabilitation. Rehabilitation was more than twofold more likely to be recommended after extracapsular stabilization than after osteotomies (P = .0142). Most respondents did not recommend bandaging beyond 24 hours postoperatively (P = .00012). CONCLUSION: Most respondents recommended either formal or informal postoperative rehabilitation therapy. CLINICAL SIGNIFICANCE: If the survey respondents are representative of veterinarians performing CrCL surgery, the current attitude is supportive of postsurgical rehabilitation. Most respondents would welcome evidence-based guidelines for rehabilitation protocols.

Custom acetabular prosthesis for total hip replacement: A case report in a dog with acetabular bone loss after femoral head and neck ostectomy.

OBJECTIVE: To describe the application of a custom acetabular prosthesis (CAP) for total hip replacement (THR) in a dog 20 months after femoral head and neck ostectomy (FHNO). STUDY DESIGN: Case report. ANIMAL: A 10-year-old, male, castrated, Labrador retriever with progressive lameness and pain after FHNO. METHODS: Acetabular bone stock was assessed as insufficient for conventional THR, so a biflanged CAP was designed and three-dimensionally printed in titanium to bridge the bone defect. The CAP had a porous surface for long-term biologic fixation on the backside and was anchored to the ilium and ischium with screws. A polyethylene cup was cemented into the CAP, and a bolted cementless femoral stem was inserted. RESULTS: The loss of the conventional anatomic landmarks complicated intraoperative orientation and led to eccentric reaming and 5-mm malalignment of the CAP. Reduction of the prosthetic joint was difficult because of periarticular fibrosis, loss of functional muscle length, and thickness of the CAP, and intraoperative shortening of the stem neck was required. Postoperative complications included sciatic neurapraxia, which resolved with time and conservative management. Absence of pain and improvement of range of motion were observed at clinical examination 12 months after surgery; however, moderate hind limb lameness persisted due to muscle tension. No evidence of implant loosening was noted on radiographs acquired 24 months after surgery. CONCLUSION: Femoral head and neck ostectomy with poor functional outcome was ameliorated by using a CAP in this dog. CLINICAL SIGNIFICANCE: Use of a CAP can be considered to treat acetabular defects in dogs.

Use of a cerclage cable-plate system to stabilize a periprosthetic femoral fracture after total hip replacement in a dog.

OBJECTIVE: To report the successful use of cerclage cables around the periprosthetic region of a femoral fracture after total hip replacement (THR) in a dog with bone stock too limited for other methods of fixation. STUDY DESIGN: Case report. ANIMAL: 6-year-old male neutered, golden retriever. METHODS: Locking plate fixation of a type-B1 diaphyseal periprosthetic femoral fracture (PFF) failed 14 days after cementless THR and 6 days after initial femoral fracture repair. Total hip replacement implants seemed unchanged on radiographs, but lateral retraction of the screw-plate construct from the proximal segment was evident. Bone stock was assessed as insufficient for adequate screw purchase, prompting revision of the fixation with cerclage cable fixation of the proximal segment; the cables were anchored to the original locking plate construct with threaded positioning pins that screwed into the locking holes. RESULTS: Acceptable union was documented on radiographs by 3 months after revision. No lameness and good range of motion of the hip were observed on clinical examination 13 months after surgery. Radiographs at 13 months documented static implant positioning and remodeling at the fracture site. CONCLUSION: Use of a cable-plate construct to stabilize a type-B1 PFF led to successful long-term outcome in this dog. CLINICAL SIGNIFICANCE: Use of a cable-plate construct may be considered to treat type-B1 PFF with limited bone stock.