Cranial Cruciate Ligament Deficient Stifle Research Articles

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

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

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

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). 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. The ECS repaired at quasi-IPs was shown to restore cranial instability of the stifles with averaged CTT magnitudes < 1.4mm. 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. 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.

The effect of joint orientation on passive movement of the dog's stifle.

The cranial cruciate ligament (CCL) is one of numerous structures which determine the path of the tibia relative to the femur when passively flexing/extending the stifle of the dog. The effect of cutting the CCL on passive motion with the hind limb in different orientations, is unknown. The aim of this study was to describe passive movement of the tibia relative to the femur in dogs, with the hind limb in three different orientations, and with CCL intact and cut. Ten cadaveric hind limbs were obtained from dogs weighing between 20 kg and 25 kg and prepared for testing in a custom-built joint testing machine. Each hind limb was tested in three different orientations with data collected, using an electromagnetic tracking system, during 2 cycles of flexion/extension with the CCL intact and cut. Each cycle was initiated with the stifle in full extension (0°) and data was collected at 0°, 20°, 30°, 40°, 45°, and 55° of stifle flexion/extension. Flexion of the stifle resulted in caudal translation and internal rotation of the tibia relative to the femur, with cranial translation and external rotation occurring during extension along the identical path. Cutting the cranial cruciate ligament did not result in significant differences in translation or rotation when the stifle was orientated to approximated the standing position of a dog. Isometric points at the origin and insertion of the CCL can potentially be identified in CCL deficient stifles using a technique based on passive motion of an intact stifle.

The Effect of Increasing Tibial Tuberosity Advancement and Quadriceps Muscle Force on Cranial Translation of the Tibia in the Cranial Cruciate Deficient Stifle Joint in Dogs.

BackgroundCranial cruciate ligament (CCL) disease is a well-known pathology that generates both rotational and translational instability of the stifle joint that leads to osteoarthritis in dogs. Tibial tuberosity advancement (TTA) is a common surgical technique used to dynamically neutralize the tibiofemoral shear forces to achieve stifle joint stability. However, significant persistent instability has been documented in clinical cases. The purpose of this study was to evaluate the effect of increasing quadriceps load, increasing tibial tuberosity advancement, and increasing joint flexion angle on the cranial translation of the tibia relative to the femur in the cranial cruciate ligament deficient stifle joint.Methods and ResultsSix cadaveric hind limbs were collected from six healthy mixed breed dogs of medium build and prepared for biomechanical testing. The specimen was placed into a custom-made joint testing machine, and translation of the tibia relative to the femur was measured at stifle angles of 135°, 120°, and 105°. Cranial tibial thrust was generated by applying a vertical load to the metatarsal pad and the quadriceps muscle was simulated with loads of 0, 5, and 10 kg applied to the patella via a system of weights and pulleys. All specimens were tested with the CCL intact and cut, both of which served as controls. The tibial tuberosity was then advanced using both 6 mm and 9 mm cages, and the specimen was tested using the identical technique. Each specimen was loaded to failure by increasing the load applied to the pes until the sudden marked cranial translation of the tibia. Tibial tuberosity advancement with an applied quadriceps load was successful in limiting cranial tibial translation in 54/62 tests. Under similar loading conditions, TTA failed to limit cranial translation in 8 tests. The failures occurred at all angles of flexion examined. In the cases that failed cranial translation could be limited by either increasing the quadriceps load or increasing the amount of tibial tuberosity advancement.ConclusionThis study showed that TTA with an applied quadriceps load is effective at decreasing cranial tibial translation at functional joint angles.

Comparison of Two Stifle Exploratory Methods Using Mini-Arthrotomy for Diagnosis of Canine Medial Meniscal Pathology: An Ex Vivo Study.

The main aim of this study was to compare the accuracy of stifle exploratory using either a stifle distractor (SD method) or a combination of Hohmann and Senn retractors (HS method) for diagnosing canine medial meniscal tears in cranial cruciate ligament-deficient stifles. Fifteen pairs of canine cadaveric pelvic limbs were used and cranial cruciate ligament were transected in all stifles. Paired limbs were then randomly assigned to one of five groups based on the tears created in the caudal pole of the medial meniscus: no tear, peripheral detachment, or a variation in three vertical longitudinal tears. A craniomedial mini-arthrotomy was performed by two observers and diagnosis of the medial meniscal status was made utilizing the HS and SD methods. Correct diagnosis of the meniscal tear was compared for both methods and observers. Correct diagnoses were made using the HS and SD methods in 24/30 and 24/30 cases for observer 1 respectively; and in 17/30 and 19/30 cases for observer 2 respectively. There was no significant difference in the correct diagnosis of meniscal tears within each observer between the two methods. Both HS and SD methods have equal accuracy for the diagnosis of canine medial meniscal pathology for a board-certified surgeon. Unassisted surgeons using the SD method for the evaluation of the medial meniscus are at no diagnostic disadvantage compared with assisted surgeons utilizing the HS method.

Relationship of mRNA Expression of Selected Genes in Peripheral Blood and Synovial Fluid in Cranial Cruciate Ligament Deficient Stifles of Dogs.

Simple SummaryThe cranial cruciate ligament rupture is characterized by chronic inflammation, osteoarthritis of the stifle joint, and extracellular matrix degeneration of the ligament itself in dogs. Early pre-clinical cranial cruciate ligament alteration cannot be detected by clinical examination or standard radiography. Therefore, we assessed the possible relationship of inflammatory markers in peripheral blood and synovial fluid of affected stifle joints in comparison to a control. We also evaluated components of the extracellular matrix of ruptured ligaments and finally compared the tibial plateau angle and the anatomical-mechanical angle between groups. Some of the assessed inflammatory markers were significantly increased in both the peripheral blood and synovial fluid compared with the control, as were collagens. The tibial plateau angle was not significantly different; however, the anatomical-mechanical angle significantly increased in the ruptured ligaments. Our results suggest a possible positive relationship between inflammatory markers of blood and synovial fluid in cranial cruciate ligament deficient stifles compared to the control. These findings may support both local and systemic inflammation process at the same time during osteoarthritis progression. Based on this, it would be interesting to investigate the predictive osteoarthritis pathway of inflammatory cytokines, matrix metalloproteinases, and their effect on the extracellular matrix components of the cranial cruciate ligament in future studies.The cranial cruciate ligament rupture (CrCLR) is characterized by chronic inflammation and osteoarthritis (OA) of the stifle joint and extracellular matrix (ECM) degeneration of the ligament itself in dogs. Generally, OA may arise from chronic low-grade systemic inflammation. We assessed the possible relationship of inflammatory markers in the peripheral blood (PB) and synovial fluid (SF) of affected stifle joints in comparison to a control. Moreover, no study has shown the possible association between PB and SF levels of inflammatory markers in CrCLR stifles of dogs in veterinary medicine yet. We also evaluated components of ECM of CrCLR and finally compared the tibial plateau angle (TPA) and the anatomical-mechanical angle (AMA) between groups. Samples from PB and SF were examined for mRNA expression of interleukins, TNF-α and INF-γ. ECM components—collagen 1A1 and 3A1 and elastin—were examined for mRNA expression from SF. The level of relative expression for IL-1β, IL-8 and IFN-γ was significantly increased in both PB and SF in CrCLR stifles as compared with the control. Collagens were also significantly increased in CrCLR stifles. TPA was not significantly different; however, the AMA angle significantly increased in the CrCLR group. Our results suggest a possible relationship between PB and SF levels of inflammatory markers in CrCLR stifles of dogs.

Geometric modelling of error sources for tibial plateau levelling osteotomy in the dog

Tibial plateau levelling osteotomy is widely performed for stabilization of cranial cruciate ligament deficient stifles in dogs. A wide range of postoperative tibial plateau angles around the target angle has been reported. The main aim of this study was to investigate if osteotomy placement could explain this range. Landmarks were derived from 50 tibial radiographs by five observers and used to define osteotomy placement and correction angles for simulation. Observer-specific osteotomy locations with mean landmark data were used to simulate planning errors, and simulated malpositioning of the osteotomy at 5 mm and 10 mm from the ideal location was used to simulate surgical errors. The tibial plateau midpoint was used as the ideal centre of the osteotomy in this model. Planning errors mostly arose from tibial plateau misidentification, with osteotomy centre locations dispersed up to 2.4% of tibial length from ideal. Malpositioning of the osteotomy resulted in variable changes in tibial plateau angle. Synthesis with historical data suggested such changes are likely limited in magnitude in tibiae with a mechanical axis length over 140 mm, but will be greater in smaller dogs and with steeper tibial plateaus.In medium to large breed dogs, our findings indicate osteotomy inaccuracy alone cannot explain the reported postoperative ranges in tibial plateau angles. Other error sources such as rotational inaccuracies or shifts during implant placement may be more significant. Surgeons should exercise additional caution when operating small and miniature breeds due to the much larger potential for clinically significant errors in these smaller dogs.

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

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. Ex vivo study. Twelve pairs of cadaveric pelvic limbs. 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. 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). Performing a TTT in combination with a CBLO does not weaken the construct failure to load when compared with each procedure performed alone. 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.

Titanium-Alloy Anchoring System as a Suitable Method of Extracapsular Repair.

Objective: To characterize the effect of a titanium-alloy anchoring system (TAS) on the motion of the cranial cruciate ligament (CrCL) deficient stifle. To compare the motion with the TAS to that of the CrCL-intact and CrCL-deficient stifle.Study Design: Each canine pelvic limb was mounted in a loading jig under 30% body weight. Motion data was collected using an electromagnetic tracking system at stifle angles of 125°, 135°, and 145° with the CrCL-intact, CrCL-deficient and the TAS applied.Results: Total translation of the CrCL-deficient stifle following the TAS was reduced, but remained greater than the CrCL-intact stifle at angles of 125°, 135°, and 145°. Internal rotation of the TAS groups was greater than the CrCL-intact group at 145°, but not 125° and 135°. Varus motion of the TAS group was decreased compared to the CrCL-deficient group, but increased compared to the CrCL-intact group at angles of 125°, 135°, and 145°.Conclusion: Total translation and internal rotation of the CrCL-deficient stifle following the TAS differed from that of the CrCL-intact stifle. However, the TAS reduced total translation and internal rotation of the tibia relative to the femur in the CrCL-deficient stifle to levels that may yield clinically acceptable results.

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.

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). Retrospective case series. Dogs (n = 21) with CCL rupture and excessive TPA treated with m-CCWO (n = 28). 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. 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. Modified cranial closing wedge osteotomy was associated with an acceptable morbidity and resulted in satisfactory functional outcomes in most dogs of this series. Modified cranial closing wedge osteotomy should be considered as an alternative to treat CCL rupture in dogs with excessive TPA.

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

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. Experimental study. Eight paired harvested femurs. 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°). 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. The bone anchor withstood deformation at the estimated forces applied on the native cranial cruciate ligament (CCL) of toy breed dogs in both configurations. 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.

The clinical outcome of three procedures for extraarticular stabilization of cranial cruciate ligament injuries in dogs

The objective of this study was to evaluate the long-term outcomes in dogs with cranial cruciate ligament injury in which the stifle was stabilized with lateral suture stabilization, lateral suture stabilization-modified, or Securos lateral bone anchor tibial suture and monofilament nylon sutures placed at quasi-isometric points of the stifle. It is a retrospective study comprising a sample population of 49 client-owned dogs. Medical records from 2014?2016 were reviewed to identify dogs that had a cranial cruciate ligament rupture in which the stifle was stabilized using one of the aforementioned methods. The overall complication rate was 16.3% and the documented complication rate requiring implant removal was 0%. Owners reported full or acceptable function in 96% of cases. There were no significant statistical differences between the 3 techniques. Stabilization of cranial cruciate ligament-deficient stifles in dogs with lateral suture stabilization, lateral suture stabilization-modified, or Securos lateral bone anchor tibial suture is reliable with acceptable complication rates. The 3 procedures tested may be appropriate in medium-sized nonathletic dogs whose owners have limited budgets.

Modelling the Effects of Cranial Cruciate Ligament Transection, Medial Meniscal Release and Triple Tibial Osteotomy on Stability of the Canine Stifle Joint.

The aim of this study was to evaluate the ex vivo effects of sequential cranial cruciate ligament transection (CCLx), medial meniscal release (MMR) and triple tibial osteotomy (TTO) on canine stifle stability compared with the intact state, across a wide range of joint angles. Nine right hind limb preparations were instrumented to provide constant quadriceps and gastrocnemius loads in a 3:1 ratio, and extended from full flexion during fluoroscopic recording. Recordings were repeated after each of CCLx, MMR and TTO. Fluoroscopic landmarks were used to calculate tibial subluxation and patellar ligament angle. Medial meniscal release resulted in additional cranial tibial subluxation compared with CCLx. Triple tibial osteotomy restored stifle stability up to a joint angle of 125 degrees. The presence of the crossover angle could be inferred from the patellar ligament angle and subluxation curves. Our results suggest that in the cranial cruciate ligament-deficient stifle, the crossover angle at which loading shifts between the caudal and cranial cruciate ligaments is dependent on both loading and integrity of the medial meniscus. Triple tibial osteotomy improves stifle stability over a wide range of joint angles under a quadricep to gastrocnemius loading ratio of 3:1 by converting cranial tibial thrust to caudal tibial thrust, due to TTO increasing the amount of joint extension required to reach the crossover angle.

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.

Functional Anatomy of the Craniomedial and Caudolateral Bundles of the Cranial Cruciate Ligament in Beagle Dogs

The aim of this study was to investigate detailed functional anatomy of the craniomedial bundle (CrMB) and caudolateral bundle (CdLB) of cranial cruciate ligament (CrCL) for application of intra-articular anatomical reconstruction in dogs. Twelve stifle joint of 12 Beagle cadavers were used. Anatomical characteristics of femoral attachment regions of the CrCL were determined. Then, the location and area of the footprints of the CrMB and CdLB were objectively measured. Each bundle was equally divided into four fibre bundles, and changes in the fibre arrangement were recorded during stifle range of motion. Additionally, the tension of each fibre bundle at various stifle joint angles was objectively measured. The attachment region of the CrCL clearly differed from that reported in humans. The centre of the CdLB attachment site was located craniodistal to that of the CrMB on the femur and slightly caudal to that of the CrMB on the tibia. The area of the CrMB on the femoral and tibial attachment sites was larger than that of the CdLB. During stifle range of motion, each divided fibre bundle in the CrMB and CdLB was twisted intricately. The tension of the CrMB was higher than that of CdLB. The central part of the CrMB was always tense during stifle range of motion. These results may contribute to the application of anatomical reconstruction surgery for CrCL deficient stifle in dogs.

Influence of tibial plateau leveling osteotomy and tibial tuberosity advancement on passive laxity of the cranial cruciate deficient stifle in dogs.

To evaluate the effect of tibial plateau leveling osteotomy (TPLO) and tibial tuberosity transposition (TTA) on craniocaudal stability of the cranial cruciate ligament (CCL) deficient stifle at 3 joint angles. Ex vivo biomechanical study. Eight stifles from 4 dogs. One of the hind limbs was randomly assigned to undergo TPLO or TTA, with the contralateral limb assigned to the alternate procedure. Each specimen was tested with the stifle at 150°, 135°, and 120° of flexion. Cranial translation of the tibia relative to the femur was measured under cranial loads ranging from 0.2 to 2.0 kg with a single motion tracking sensor (Nest of Birds) fixed to the tibia. Each stifle was tested before and after transection of the CCL and after performing the assigned procedure. Tibial plateau leveling osteotomy and TTA caused a decrease in the cranial translation of the tibia relative to the femur, especially at greater angles of flexion. Tibial plateau leveling osteotomy caused a greater decrease in tibial cranial translation and was associated with a degree of translation that did not differ from joints with intact CCL, regardless of the degree of stifle flexion. Tibial plateau leveling osteotomy and TTA caused an angle dependent decrease in craniocaudal translation of the tibia in the CCL deficient stifle. Only TPLO restored translations similar to those of the intact joint at all angles tested. Tibial plateau leveling osteotomy and TTA provide passive stability to the stifle. Tibial plateau leveling osteotomy seems more effective than TTA at restoring craniocaudal stability of the stifle.

Evaluation, Description of the Technique, and Clinical Outcomes After Tibial Tuberosity Advancement With Cranial Fixation (TTA CF) for Cranial Cruciate Ligament Rupture in 22 Dogs

The objective of this study is to describe a modified surgical technique for tibial tuberosity advancement with cranial fixation (TTA CF) in dogs with cranial cruciate insufficiency and to report long term clinical outcomes and complications.TTA CF was performed with a novel titanium implant. A description of the specific implant with guide, drill and saw guide, instrumentation, and template are provided, along with clinical outcomes, complications, owners’ evaluation, and a 1-year postoperation follow-up.Twenty two mixed breed dogs, with a median body weight of 23 kg (range, 11-45 kg) were included. The median age at surgery was 4 years (range, 1-8 years). Clinical bone healing was seen at a mean 10 weeks (range 6-14 weeks). The minor complication rate was 27% (n = 6). No major complication occurred, and no revision surgery was required. Twenty-one (95%) dogs had a good to excellent outcome 1 year after surgery. Currently there is no accepted best treatment of the canine cranial cruciate ligament deficient stifle. Most of TTA techniques are based on fixing the implant from the medial side of tibia. We report a modified TTA technique with cranial fixation of a titanium implant and suggest that the TTA CF surgical technique may be a feasible alternative to existing surgical procedures.

Effect of Tibial Plateau Levelling Osteotomy on Cranial Tibial Subluxation in the Feline Cranial Cruciate Deficient Stifle Joint: An Ex Vivo Experimental Study.

This study evaluated the effects of tibial plateau levelling osteotomy on cranial tibial subluxation and tibial rotation angle in a model of feline cranial cruciate ligament deficient stifle joint. Quadriceps and gastrocnemius muscles were simulated with cables, turnbuckles and a spring in an ex vivo limb model. Cranial tibial subluxation and tibial rotation angle were measured radiographically before and after cranial cruciate ligament section, and after tibial plateau levelling osteotomy, at postoperative tibial plateau angles of +5°, 0° and -5°. Cranial tibial subluxation and tibial rotation angle were not significantly altered after tibial plateau levelling osteotomy with a tibial plateau angle of +5°. Additional rotation of the tibial plateau to a tibial plateau angle of 0° and -5° had no significant effect on cranial tibial subluxation and tibial rotation angle, although 2 out of 10 specimens were stabilized by a postoperative tibial plateau angle of -5°. No stabilization of the cranial cruciate ligament deficient stifle was observed in this model of the feline stifle, after tibial plateau levelling osteotomy. Given that stabilization of the cranial cruciate ligament deficient stifle was not obtained in this model, simple transposition of the tibial plateau levelling osteotomy technique from the dog to the cat may not be appropriate.

Technique of Tibial Tuberosity Transposition and Advancement (TTTA) With Use of TTA-Maquet Cage-Only in Dog

Background: The most common conditions that compromise the stifle joint in dogs are medial patellar luxation (MPL) and cranial cruciate ligament (CCL) rupture. Surgical procedures are usually indicated for the treatment of these diseases. One ordinary technique for the treatment of MPL is the tibial tuberosity transposition, and one prominent technique for CCL rupture is the tibial tuberosity advancement. These techniques can be associated in one surgical procedure called tibial tuberosity transposition and advancement (TTTA) for the simultaneous treatment of both stifle diseases. The aim of this study is to report the surgical treatment of a dog with MPL and CCL rupture affecting the same joint by the TTTA technique with the use of a TTA-Maquet cage-only.Case: A 3-year-old Pitbull dog weighing 39 kg was attended at Veterinary Hospital with a history of marked lameness in the left pelvic limb. The orthopedic examination showed positive results for cranial drawer motion and tibial compression tests, and a complete CCL rupture was diagnosed. The presence of patellar luxation was evaluated by manual pressure on the patella, and grade 3 of MPL was diagnosed. Both conditions were affecting the same stifle joint. In addition, survey radiographs of the affected joint were performed. Surgical treatment was indicated by the TTTA technique. Radiographic measurements were taken to calculate the cranial tibial tuberosity advancement by the tibial plateau and the common tangent methods, and a titanium TTA-Maquet cage-only of 10.5 x 20.0 mm was selected. Linear osteotomy was performed on the tibial tuberosity with the aid of an oscillating saw, based on the Maquet hole technique. The tibial tuberosity was carefully displaced cranially and the cage was inserted at the site of osteotomy. The cage ears were molded on the tibial surface and fixed with 2.4 mm self-tapping cortical screws. At the moment of the cage attachment to the tibial tuberosity, orthopedic washers of 2 mm wide were placed between the cranial ears of the cage and the tibial tuberosity, thus promoting a lateral transposition of the tibial tuberosity. The patient was maintained in the early postoperative period with Robert Jones bandage, and with antibiotic, analgesic and anti-inflammatory drugs. On the second day after the procedure partial limb support with presence of mild lameness was observed. At three months postoperatively, the animal had no claudication and MPL was corrected. The radiographic examination showed the proper process of bone repair at the osteotomy site. In the clinical evaluation performed at one year after surgery the patient was in good condition without lameness and with proper limb support and muscular gain.Discussion: The studies that evaluated the association of tibial tuberosity transposition and tibial tuberosity advancement techniques (TTTA) for the simultaneous treatment of MPL and CCL rupture demonstrated that this is a viable and effective procedure. In this report, the accomplishment of tibial osteotomy based on the Maquet hole and the advancement of the tibial tuberosity with the TTA-Maquet cage-only allowed the dynamic stabilization of the CCL deficient stifle and the early use of the affected limb. In addition, the TTTA technique proved to be effective for the correction of grade 3 of MPL in a large dog, allowing adequate recovery of the limb function without complications during a one year evaluation period.

Use of a novel extracapsular bone anchor system for stabilisation of cranial cruciate ligament insufficiency.

To evaluate early clinical experiences using the novel extracapsular bone anchor Ruby system for stabilisation of the cranial cruciate ligament deficient stifle in the dog and report short-term outcome and complications for 17 clinical cases. Seventeen dogs with cranial cruciate ligament insufficiency were treated using the Ruby system. Dogs were eligible if diagnosed via orthopaedic examination with unilateral or bilateral cranial cruciate ligament instability without any comorbidities. Subjective lameness assessments on a 0 to 4 scale were made pre-operatively and at six to eight weeks post-operatively; complications were also recorded. Lameness was also assessed on a visual analogue scale at six to eight months post-operatively. All cases had substantial improvement in lameness following surgery. Mean post-operative lameness grade was 1·18 (±0·53) out of 4, compared to a grade of 3·06 (±0·9) before surgery, and owner assessment at six to eight months after surgery was also positive. There were major complications that required surgical intervention in one dog. The Ruby system is a feasible method of extracapsular stabilisation with comparable outcomes and complication rates to previously reported methods of addressing cranial cruciate ligament insufficiency. Further work is required to acquire more data on objective outcome measurement and mechanisms of failure.