Long-term arthroscopic assessment of intra-articular allografts for treatment of spontaneous cranial cruciate ligament rupture in the dog.

OBJECTIVE: To assess the 12-month survival of intra-articular, decellularized allografts for the treatment of cranial cruciate ligament disease (CCLD) in dogs. STUDY DESIGN: Prospective case series. ANIMALS: Twenty client-owned dogs with spontaneous CCL rupture. METHODS: Affected stifles were treated solely by implantation of an intra-articular, decellularized, deep digital flexor tendon allograft. Functional outcome was evaluated at baseline and at 6 and 12 months after surgery with the Liverpool Osteoarthritis for Dogs questionnaire and force platform gait analysis. At 12 months after surgery, dogs underwent arthroscopy to visually assess the allografts. RESULTS: Scores on owner questionnaires (improved 62.5%; P = .005) and ground reaction forces (improved 34.4%; P = .017) were improved in all dogs 12 months after surgery. Dogs with an intact graft (IG) were more likely to have a successful outcome compared with dogs with a torn graft (P = .011). According to arthroscopy, 45% of grafts seemed to survive at 12 months after surgery. CONCLUSION: About half of intra-articular allografts survived 12 months after implantation in CCL-deficient stifles. Dogs with IG had successful outcomes at 12 months after surgery according to assessment by force platform gait analysis. CLINICAL SIGNIFICANCE: These results preclude immediate clinical application but provide evidence to justify further investigation of intra-articular grafts as a repair option for CLLD.

Ex Vivo Biomechanical Comparison of Titanium Locking Plate, Stainless Steel Nonlocking Plate, and Tie-in External Fixator Applied by a Dorsal Approach on Ostectomized Humeri of Pigeons (Columba livia).

To compare the bending strength of a locking plate (LP), nonlocking plate (NLP), and an external skeletal fixator intramedullary pin (ESF-IM) tie-in fixation applied by a dorsal approach in an avian humerus fracture model, 5 left humeri obtained from pigeon (Columba livia) cadavers were randomly assigned to each repair technique (n = 15). The ESF-IM group was repaired with a 0.062-inch intramedullary pin tied-in with two 0.035-inch positive profile transfixation pins using acrylic filled plastic tubing. The LP group was repaired with a dorsally applied titanium 1.6-mm screw 7-hole locking plate (1 bicortical and 2 monocortical screws in each segment). The NLP group was repaired with a dorsally applied 6-hole stainless steel 1.5-mm dynamic compression plate (all bicortical screws). All constructs were applied before complete ostectomy to allow perfect reconstruction. Constructs were cyclically tested nondestructively for 1000 cycles in four-point bending before being tested to failure. Outcome measures included stiffness, strength, and strain energy. All specimens cycled without failure. The ESF-IM specimens were significantly stiffer and stronger than the plated repair groups. Plated constructs had significantly higher strain energies than ESF-IM. LP and NLP were of equal stiffness, strength, and strain energies. This study demonstrated that bending biomechanical properties of the ESF-IM configuration were superior to those of the dorsal plate fixation. Exact properties of fixation required to facilitate avian fracture healing are largely unknown. Further study, including assessments of optimal plate position and configuration, and torsional and in vivo studies in avian species are warranted.

Contribution of antirotational pins and an intact fibula to the ex vivo compressive strength of four tibial plateau leveling osteotomy constructs.

OBJECTIVE To assess the contribution of antirotational pins (ARPs) and an intact fibula to the compressive strength of 4 tibial plateau leveling osteotomy (TPLO) constructs (bone and implants). SAMPLE 20 hind limbs from 10 canine cadavers. PROCEDURES Each hind limb was assigned to 1 of 4 TPLO constructs (construct in which the ARP was removed, constructs in which 1 or 2 ARPs were left in place, and construct in which the ARP was removed and the fibula was cut). Following TPLO completion, all limbs underwent mechanical testing that included 10,000 cycles of cyclic axial compression followed by testing to failure at a displacement rate of 1 mm/s. Displacement during cyclic testing; load generated at 0.5, 1.0, and 3.0 mm of displacement; ultimate load; and failure type were recorded for each limb. Mean values were compared among the groups. RESULTS None of the specimens failed during cyclic testing. None of the variables assessed during mechanical testing differed significantly among the 4 groups. During testing to failure, the majority (17/20) of specimens failed as the result of a long oblique fracture through the first screw hole in the distal segment. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that the axial compressive strength and stiffness of a TPLO construct were not significantly affected by the addition of 1 or 2 ARPs or the presence of an intact fibula. These findings appear to support removal of ARPs during uncomplicated TPLOs, but further research is warranted to assess the effect of ARP removal on bone healing and complication rates.

Effects of low-level laser therapy on the healing of surgically closed incisions and surgically created open wounds in dogs.

OBJECTIVE: To determine the effects of low-level laser therapy (LLLT) on primarily closed incisions and full thickness open wounds in dogs. STUDY DESIGN: Prospective, masked, placebo-controlled design. ANIMAL POPULATION: Healthy intact female dogs (n = 10). METHODS: Dogs underwent bilateral flank ovariectomy procedures, and open wounds were created bilaterally with a punch biopsy. Each side of the dog (incision and open wound) was randomly assigned to the treatment (TX) group or the control (CN) group. The TX group received LLLT once daily for 5 days with a 980-nm laser and a total energy density of 5 J/cm2 . The CN group received a sham treatment (laser turned off) for an identical amount of time each day. The wounds were assessed visually; measured; photographed at postoperative days 3, 7, 11, and 14; and biopsied on postoperative days 7 and 14. A 2-way repeated measures multivariate analysis of variance was used to analyze differences between groups. RESULTS: There was no difference between groups for subjective assessment of healing time and wound measurements (P = .7). There was no difference in histopathologic assessment except that the CN group had more necrosis and perivascular lymphocytes and macrophages at day 7 (P = .03). The TX group had more perivascular lymphocytes and macrophages at day 14 (P = .01). CONCLUSION: LLLT did not appear to influence the healing of surgically created incisions and small wounds with the methodology reported here. CLINICAL SIGNIFICANCE: Results of this study do not support recommending LLLT to stimulate healing of uncomplicated, small wounds and incisions.

A novel jig arm to measure tibial plateau angle during tibial plateau leveling osteotomy.

OBJECTIVE: To determine the ability of a novel device attached to the proximal tibial plateau leveling osteotomy (TPLO) jig pin to accurately predict intraoperative change in tibial plateau angle (TPA). STUDY DESIGN: In vitro cadaveric study. SAMPLE POPULATION: Left hindlimbs of adult dogs (n = 9). METHODS: A modified Slocum tibial plateau leveling (TPL) jig with the Rotational Osteotomy Measuring Arm (ROMA) was placed on the tibia and a radial TPLO osteotomy was performed. Based on preoperative radiographic TPA measurements, the proximal segment was rotated using the traditional method of marking points on the osteotomy a specified distance apart. After rotation, the predicted TPA was recorded based on the ROMA. Postoperative TPA was measured on radiographs. The ability of the ROMA to predict postoperative TPA was compared to that of the traditional method. RESULTS: The average final TPA achieved with the traditional method was 6.4° (range, 3.0-10.0°). The ROMA predicted a final TPA of 5.8° (range, 3.8-10.1°). No significant difference was found between the TPA predicted based on the traditional method and ROMA method. CONCLUSION: The ROMA may be an alternative to the traditional method of measuring proximal segment rotation during TPLO procedure. CLINICAL RELEVANCE: Performing a TPLO with the ROMA may accurately predict the postoperative TPA while eliminating the need for measuring chord length, making reference marks, or referencing TPA charts for various osteotomy blade sizes.

Long-term outcome of an intra-articular allograft technique for treatment of spontaneous cranial cruciate ligament rupture in the dog.

OBJECTIVE: To determine the 12-month outcome in dogs with spontaneous cranial cruciate ligament (CCL) rupture after repair with an intra-articular decellularized allograft. STUDY DESIGN: Prospective pilot case series. ANIMALS: Ten client-owned dogs with unilateral CCL rupture. METHODS: An intra-articular, decellularized, deep digital flexor tendon allograft was secured in the stifle with a femoral cross pin and tibial spiked washers and screws. An interference screw was placed in the tibial tunnel. Dogs were evaluated with an owner questionnaire, radiographs, and force platform gait analysis before and 2, 6, and 12 months after surgery. RESULTS: Owners reported improvement in level of pain and mobility throughout the study, especially over the first 6 months. Peak vertical force and vertical impulse improved across all time points. Ground reaction force asymmetry index for peak vertical force and vertical impulse at 12 months showed 3 dogs within a normal index (<6%), 4 dogs as nonvisibly lame (6-20%), and 3 dogs as visibly lame (≥20%). For most dogs, osteoarthritis scoring did not change over the 12-month period and some femoral-tibial translation was detected on standing horizontal beam radiographs. CONCLUSION: Intra-articular repair using a decellularized allograft can provide functional clinical outcomes in dogs with CCL disease. A better understanding of long-term engraftment after this procedure is needed.

Simultaneous staphylectomy and unilateral arytenoid lateralization in dogs presenting for dyspnea: 23 cases (2010-2013).

This retrospective study assesses postoperative complications with simultaneous staphylectomy and unilateral arytenoid lateralization (SP + UAL) in dogs with laryngeal paralysis and concurrent elongation of the soft palate compared to dogs having a UAL alone. Medical records of dogs having a UAL performed from 2010 to 2013 were reviewed. Twenty-three dogs were diagnosed with a concurrent elongated soft palate and had a SP + UAL performed and 89 dogs were diagnosed with an appropriate soft palate and had only a UAL performed. A telephone questionnaire for long-term postoperative outcomes was completed. Survival probability was not statistically different between the 2 groups. Dogs in the SP + UAL group were more likely to be seen for respiratory distress after surgery (P = 0.05). There was no significant difference between the 2 groups in the number of dogs which developed postoperative aspiration pneumonia. The overall complication rate for both groups was high, with postoperative pneumonia being the most common complication.

Staphylectomie et latéralisation unilatérale de l'arythénoïde simultanées chez des chiens manifestant de la dyspnée : 23 cas (2010­2013). Cette étude rétrospective évalue les complications postopératoires associées à une staphylectomie et à une latéralisation unilatérale de l'arythénoïde (SP + LAU) simultanée chez des chiens atteints de paralysie laryngée et d'allongement concomitant du palais mou comparativement à des chiens atteints seulement de LAU. Les dossiers médicaux de chiens qui avaient subi une LAU de 2010 à 2013 ont été examinés. Vingt-trois chiens ont été diagnostiqués avec un palais mou allongé concomitant et ont subi une SP + LAU et 89 chiens ont été diagnostiqués avec un palais mou conforme et avaient subi seulement une LAU. Un questionnaire téléphonique pour les résultats postopératoires à long terme a été rempli. La probabilité de survie n'était pas statistiquement différente entre les deux groupes. Il était plus probable que les chiens du groupe SP + LAU soient examinés pour une détresse respiratoire après la chirurgie (P = 0,05). Il n'y avait pas de différence statistiquement significative entre les deux groupes quant au nombre de chiens qui ont développé une pneumonie de déglutition postopératoire. Le taux de complication global était élevé pour les deux groupes et la pneumonie postopératoire était la complication la plus fréquente.(Traduit par Isabelle Vallières).

Biochemical, histologic, and biomechanical characterization of native and decellularized flexor tendon specimens harvested from the pelvic limbs of orthopedically normal dogs.

OBJECTIVE: To evaluate the biochemical and biomechanical properties of native and decellularized superficial digital flexor tendons (SDFTs) and deep digital flexor tendons (DDFTs) harvested from the pelvic limbs of orthopedically normal dogs. SAMPLE: 22 commercially supplied tendon specimens (10 SDFT and 12 DDFT) harvested from the pelvic limbs of 13 canine cadavers. PROCEDURES: DNA, glycosaminoglycan, collagen, and protein content were measured to biochemically compare native and decellularized SDFT and DDFT specimens. Mechanical testing was performed on 4 groups consisting of native tendons (5 SDFTs and 6 DDFTs) and decellularized tendons (5 SDFTs and 6 DDFTs). All tendons were preconditioned, and tension was applied to failure at 0.5 mm/s. Failure mode was video recorded for each tendon. Load-deformation and stress-strain curves were generated; calculations were performed to determine the Young modulus and stiffness. Biochemical and biomechanical data were statistically compared by use of the Wilcoxon rank sum test. RESULTS: Decellularized SDFT and DDFT specimens had significantly less DNA content than did native tendons. No significant differences were identified between native and decellularized specimens with respect to glycosaminoglycan, collagen, or protein content. Biomechanical comparison yielded no significant intra- or intergroup differences. All DDFT constructs failed at the tendon-clamp interface, whereas nearly half (4/10) of the SDFT constructs failed at midsubstance. CONCLUSIONS AND CLINICAL RELEVANCE: Decellularized commercial canine SDFT and DDFT specimens had similar biomechanical properties, compared with each other and with native tendons. The decellularization process significantly decreased DNA content while minimizing loss of extracellular matrix components. Decellularized canine flexor tendons may provide suitable, biocompatible graft scaffolds for bioengineering applications such as tendon or ligament repair.

Mechanical strength of four allograft fixation techniques for ruptured cranial cruciate ligament repair in dogs.

OBJECTIVE: To test ex vivo mechanical properties of 4 allograft fixation techniques for cranial cruciate ligament (CCL) replacement. SAMPLE: 30 stifle joints from canine cadavers. PROCEDURES: CCL-deficient stifle joints repaired by 1 of 4 techniques (n = 6/group) and CCL-intact stifle joints (control group; 6) were mechanically tested. Three repair techniques involved a patella-patella ligament segment (PPL) allograft: a tibial and femoral interference screw (PPL-2S), a femoral interference screw and the patella seated in a tapering bone tunnel in the tibia (PPL-1S), or addition of a suture and a bone anchor to the PPL-1S (PPL-SL). The fourth technique involved a deep digital flexor tendon (DDFT) allograft secured with transverse femoral fixation and stabilized with a tibial interference screw and 2 spiked washers on the tibia (DDFT-TF). The tibia was axially loaded at a joint angle of 135°. Loads to induce 3, 5, and 10 mm of femoral-tibia translation; stiffness; and load at ultimate failure with the corresponding displacement were calculated. Group means were compared with a multivariate ANOVA. RESULTS: Mean ± SD load for the intact (control) CCL was 520.0 ± 51.3 N and did not differ significantly from the load needed to induce 3 mm of femoral-tibial translation for fixation techniques PPL-SL (422.4 ± 46.3 N) and DDFT-TF (654.2 ± 117.7 N). Results for the DDFT-TF were similar to those of the intact CCL for all outcome measures. CONCLUSIONS AND CLINICAL RELEVANCE: The DDFT-TF yielded mechanical properties similar to those of intact CCLs and may be a viable technique to test in vivo.

Ability of the Tightrope® and percutaneous lateral fabellar suture techniques to control cranial tibial translation.

OBJECTIVE: To compare the ability of the Tightrope® (TR) cranial cruciate ligament (CCL) technique, percutaneous lateral fabella suture (pLFS) technique, and normal CCL to control cranial tibial translation (CTT). STUDY DESIGN: In vitro biomechanical study. SAMPLE POPULATION: Cadaveric canine pelvic limbs (n = 18 pairs). METHODS: Six small animal surgical residents (1 pair each) and a Diplomate of the American College of Veterinary Surgeons (10 pairs) performed TR and pLFS techniques on paired limbs. Two intact limb pairs served as controls. Limbs were assessed by palpation, radiographs, and dissection before mechanical testing of resistance to CTT. Forces resisted during displacement were compared between groups with a mixed ANOVA and post hoc tests. RESULTS: With 5 mm of displacement, the pLFS resisted 72 ± 45 N and the TR resisted 66 ± 48 N of load. The intact CCL resisted 400 ± 35 N. The intact CCL resisted displacement significantly more than either surgical technique. CONCLUSIONS: TR and pLFS had similar ability to resist CTT but neither restored the biomechanical properties of an intact CCL.

Technical difficulties during the training phase for Tightrope® and percutaneous lateral fabellar suture techniques for cranial cruciate ligament repair.

OBJECTIVE: To compare level of difficulty, deviations from technical description and postoperative assessment during the training of veterinary students, small animal surgical residents, and a board certified surgeon for Tightrope® (TR) and percutaneous lateral fabella suture (pLFS) techniques for cranial cruciate ligament (CCL) repair. STUDY DESIGN: Prospective study. SAMPLE POPULATION: Cadaveric canine pelvic limbs (n = 32). METHODS: Sixteen 3rd year veterinary students, 6 small animal surgical residents and a Diplomate of the American College of Veterinary Surgeons performed the TR and pLFS techniques on paired limbs. Perceived level of difficulty, duration of surgery, and technical deviations were assessed by questionnaire, radiographs, and dissection. Results were compared between techniques with McNemar's test. RESULTS: The TR procedure was perceived as more technically demanding than the pLFS by veterinary students and residents. Technical deviations were overall more common after TR than pLFS, and in limbs repaired by students, regardless of procedure. The most difficult aspect of the TR consists of the bone tunnels whereas for pLFS it was passing the suture around the femorofabellar ligament. The sensitivity of radiographs for detection of technical deviations was 39% after TR and 50% after pLFS. CONCLUSION: Technical deviations are more common during the training phase of TR than pLFS, and the sensitivity of radiographs to detect those is low. Repeated practice on cadavers followed by dissection is recommended before use in patients.