Jeffery J. Biskup

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 McNemars 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.

Ability of the Tightrope® and Percutaneous Lateral Fabellar Suture Techniques to Control Cranial Tibial Translation: Ability of Tightrope® and pLFS Repairs 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.

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.

Mechanical properties of canine patella-ligament-tibia segment.

OBJECTIVE To test the ex vivo mechanical properties of canine patella-ligament-tibia (PLT) segment and establish the relationship between donor size and PLT dimensions to the mechanical properties of PLT grafts. STUDY DESIGN Ex vivo mechanical testing study. SAMPLE POPULATION Canine PLT segments (n = 21 dogs; 42 PLT). METHODS Morphometric measurements of PLT segments were taken from computed tomography (CT) images and compared with results obtained using calipers. PLT were tested to failure at a rate of 100% length/s. Mechanical properties and failure mode were recorded. RESULTS PLT width and thickness (P < .001 for both) measured by calipers were significantly lower than those taken from CT images. Thirty-five (83%) specimens failed by avulsion fracture from the patella, 1 failed mid-ligament, and 6 failed by tibial fracture. Dog weight and PLT length had the strongest Pearsons r value when correlated with load at failure (r = 0.73, 0.81, respectively). CONCLUSION Dog weight and PLT length were the best predictors of load at failure. PLT failure load of dogs weighing >25 kg were similar to those reported for the cranial cruciate ligament (CCL) suggesting that the PLT may be a suitable allograft for CCL replacement.

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.

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.

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.

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.

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.

Gastro-oesophageal intussusception with splenic involvement in an adult dog

Summary This case report describes the presentation, treatment and outcome of an adult German shepherd dog with gastroesophageal intussusception (GEI). The dog’s presenting complaint included acute lethargy, and a single bout of excessive drinking followed by immediate regurgitation. After patient stabilisation, radiographs were taken which revealed a soft tissue opacity in the caudodorsal thorax and lack of a gastric silhouette in the abdomen. The patient was diagnosed with GEI, a laparotomy was performed and the stomach and spleen were surgically reduced. A right-sided incisional gastropexy, left-sided tube gastropexy, splenectomy and narrowing of the oesophageal hiatus were performed. The patient developed aspiration pneumonia postoperatively, likely secondary to megaoesophagus, which responded to antimicrobials. The gastric tube was removed 31 days after surgery and the patient had no further clinical signs eight months postoperatively.