Preliminary experiences of the triple tibial osteotomy procedure: tibial morphology and complications

A modified triple tibial osteotomy for management of canine cranial cruciate ligament disease: retrospective assessment of 309 procedures (2017-2020)

CASE HISTORY

Medical records from a single referral hospital (Animal Referral Hospital, Sinnamon Park, Australia) of dogs treated with modified triple tibial osteotomy (TTO) for management of cranial cruciate ligament (CrCL) disease from June 2017 to June 2020 were reviewed. Modifications to the originally described TTO procedure included a modified wedge angle calculation and performing the tibial osteotomies without the use of pre-drilled guide holes.

CLINICAL FINDINGS

A total of 253 dogs met the inclusion criteria. Two dogs were excluded, leaving 251 dogs that had undergone 309 procedures for assessment, and data from these, including complications, were reviewed. Complete, partial competent, and partial incompetent rupture of the cranial cruciate ligament was identified in 202/309 (65.4%), 79/309 (25.6%), and 28/309 (9.1%) stifles, respectively. Medial meniscal injury was identified in 207/309 (67.0%) stifles at the time of initial surgery.

TREATMENT AND OUTCOME

Fifty-eight dogs had bilateral procedures, including both single-session and staged surgeries, and 48 of these were available for analyses. The modifications to the TTO procedure described herein resulted in a median wedge angle of 21° and a median post-operative tibial plateau angle of 5.8°. Tibial compression testing following surgery indicated elimination of cranial tibial thrust in all stifles in this series. The most common intra-operative complication was tibial tuberosity fracture (15/309; 4.9%). Minor post-operative complications occurred in 37/309 (12.0%) procedures, with infection being the most common (27/309; 8.7%). Major post-operative complications occurred in 9/309 (2.9%) procedures. The intra- and post-operative complication rates for dogs undergoing bilateral single-session TTO were both 8.3% (2/24). The intra- and post-operative complication rates for dogs undergoing bilateral staged TTO were both 4.2% (1/24). The low number of complications for both the bilateral single-session and bilateral staged TTO groups precluded statistical analysis. All complications resolved uneventfully as determined by the attending surgeon.

CLINICAL RELEVANCE

The modified TTO technique described here was safe and effective for the management of canine CrCL disease in the dogs included in the case series. Findings of this study suggest that, with careful case selection, the modified TTO may be performed as a bilateral single-session procedure in dogs with concurrent bilateral cranial cruciate ligament disease. Future studies analysing the effects of these modifications on stifle biomechanics would be beneficial.

ABBREVIATIONS

CrCL: Cranial cruciate ligament; SSI: Surgical site infection; TPA: Tibial plateau angle; TPLO: Tibial plateau levelling osteotomy; TTA: Tibial tuberosity advancement; TTO: Triple tibial osteotomy.

Intercondylar width index of the tibia in the dogs: A morphological study

Morphological characteristics of the proximal tibia affect the orthopedic balance of the knee region. Such as the width of the condyles, tibial plateau angle, position of the patella; Intercondylar width is one of these features as well. The objectives of this study are to calculate the intercondylar width index of the tibia (ICWI) in dogs, to determine if there are gender-related differences in ICWI, and to compare the ICWI among the six breeds of dog. For these aims, the tibial bones of 84 dogs from 26 different breeds were used. The radiographs of tibias were taken, and the tibial plateau and intercondylar widths were measured. The intercondylar width index was calculated using the following formula: (intercondylar width/tibial plateau width) *100. The mean intercondylar width index of the dogs was 19.2±2.72. The index values of male and female dogs were 19.1±3.32 and 19.3±2.02, respectively. The significant differences in the index were not determined between male and female dogs, but the significant difference was determined among dogs’ breeds. The dogs in the high-risk breeds had significantly smaller eminence width index value than the dogs in the low-risk breeds related with the non-traumatic cranial cruciate ligament rupture. The results of this study suggested performing further clinical studies to evaluate whether the difference in intercondylar width index among breeds in dogs is associated with cranial cruciate ligament deficiency.

Inter- and Intra-Observer Variations in Radiographic Evaluation of Pelvic Limbs in Yorkshire Terriers with Cranial Cruciate Ligament Rupture and Patellar Luxation

The main aims of the study were to describe bone alignment differences in Yorkshire Terriers (YT) with cranial cruciate ligament rupture (CCLR), patellar luxation (PL), or with a combination of both (CCLR + PL); to verify the theory of increased strain on cranial cruciate ligament (CrCL) due to PL as a predisposing factor; and to evaluate intra- and inter-observer variability of the protocols developed for measurement of femoral and tibial alignment in Yorkshire Terriers. Fifty-five hindlimbs of YT were divided into four groups: Control, CCLR, PL, and CCLR + PL. Thirty parameters were radiographically evaluated including hip joint, femoral, tibial, and intercondylar fossa (ICF) parameters. Three observers evaluated all parameters on two separate occasions with a twelve-week interval between measurements. Significant differences in conjunction with CCLR and PL theories between groups were noticed in: Norberg angle (NA), quadriceps angle (Qa), anatomic lateral distal femoral angle (aLDFA), femoral varus (FVA), mechanical cranial proximal tibial angle (mCrPTA), mechanical caudal proximal tibial angle (mCdPTA), tibial plateau angle (TPA), distal tibial axis/proximal tibial axis angle (DPA). Some interesting findings are the similarity of values between Control and CCLR vs. CCLR + PL and PL groups in Na, Qa, aLDFA; between CCLR + PL and PL in FVA and a significantly lower age of dogs in CCLR + PL compared to CCLR group. Based on our results, we can conclude that YT with different clinical findings have differing bone morphology. Moreover, these findings may support PL as a predisposing factor for CCLR in small breeds. Measurements in which excellent inter- observer agreement was achieved may be used for surgical planning or for further discussions.

Modified Triple Tibial Osteotomy for Combined Cranial Cruciate Ligament Rupture, Tibial Deformities, or Patellar Luxation

Proximal tibial deformities or patellar luxation may occur concurrently with cranial cruciate ligament rupture. The objective of this study was to describe the management of those conditions with a modified triple tibial osteotomy (TTO) in nine dogs. Medical records of dogs who underwent a modified TTO were reviewed. The mean pre- and postoperative patellar tendon angles were 104.2° and 92.9°, respectively. The mean pre- and postoperative mechanical medial proximal tibial angles were 99.5° and 91.5°, respectively. Medial patellar luxation was present in five dogs (55.6%) and treated in all five dogs with a tibial crest transposition. Tibial torsion was grossly resolved in two dogs (22.2%). Perioperative distal tibial crest fracture was treated by pins and a figure-of-eight tension-band wire in five dogs (55.6%). One major (surgical site infection) and three minor postoperative complications were observed. At the last follow-up, seven dogs (77.8%) had no lameness, one dog (11.1%) had mild lameness, and one dog (11.1%) had moderate lameness. Radiographic evaluation showed good (2/9; 22.2%) to excellent (7/9; 77.8%) bone healing. The visual analog scale evaluation revealed good-to-excellent owner satisfaction. Cranial cruciate ligament rupture, tibial deformities, and medial patellar luxation are difficult to treat together. A modified TTO may be used to treat these conditions.

Planned wedge size compared to achieved advancement in dogs undergoing the modified Maquet procedure

Objectives: To evaluate the patellar ligament to tibial plateau angle (PL-TPA) and amount of achieved advancement in dogs that underwent the modified Maquet procedure; compare wedge sizes recommended using two different planning techniques (Orthomed and modified tibial tuberosity advancement); and evaluate anatomical factors that predict the wedge size required to obtain a 90° PL-TPA.

Methods: Pre- and postoperative radio-graphs of dogs that had a modified Maquet procedure performed were evaluated for the following: calculated wedge size using two different planning techniques, the actual wedge size used, the achieved tibial tuberosity advancement, and the changes in PL-TPA. Anatomical measurements of the tibia were evaluated and correlated with the actual wedge size.

Results: Of the 38 modified Maquet procedures identified, 53% (n = 20) had a PLTPA of 90° ± 5°. Actual achieved advancement of the tibial tuberosity was 30% less than the wedge size used. Changes in PL-TPA and tibial width persisted at eight weeks postoperatively without loss of advancement. The two planning techniques did not result in a significantly different selection of wedge size.

Clinical relevance: Current planning techniques for the modified Maquet procedure result in under-advancement of the tibial tuberosity. Both measurement techniques evaluated do not result in appropriate advancement.

Radiographic and ultrasonographic changes of the patellar ligament following tibial tuberosity advancement in 25 dogs

Introduction: Patellar ligament thickening is a recognized response following osteotomy of the proximal tibia as a treatment for cranial cruciate disease. In humans this is seen as a response to increased loading, but the reason for this thickening in dogs is unclear. A prospective study was undertaken to assess the degree and frequency of patellar ligament desmopathy in 25 consecutive cases undergoing tibial tuberosity advancement (TTA).

Objectives: To determine the incidence of patellar ligament thickening following TTA.

Methods: Consecutive cases undergoing TTA had ultrasonographic and radiographic measurements performed of the patellar ligament, at multiple positions on the ligament. This was performed at the time of surgery, and at six weeks and six months (ultrasound only) following surgery. The radiographic measurements were performed by two reviewers who were blinded to the timeframe of each image.

Results: There was great variation in both the incidence and degree of thickening of the ligament. Fifty percent of the cases showed no changes in the thickness of the patellar ligament. A clinical pain response was not associated with patellar ligament thickening. No statistically significant variables which predicted the development of patellar ligament thickening were identified .

Clinical significance: The presence of signs of patellar ligament thickening is of questionable clinical significance and is probably an incidental finding.

Effect of use of different landmark methods on determining stifle angle and on calculated tibial tuberosity advancement

Objectives: Firstly, to investigate the effect that using different landmarks has on the measured stifle angle. Secondly, to determine whether any differences in measured stifle angle would lead to variations in the required extent of tibial tuberosity advancement (TTA).

Methods: Three greyhound stifles were positioned in a total of 66 different angles. Radiographic exposures of each stifle angle were made. For each radiograph i) the stifle angle was measured using each of three sets of landmarks and ii) the extent of TTA required to obtain a patella tendon angle of 90° was measured. Each radiograph was plotted graphically according to the stifle angle and the extent of TTA required. Linear regression analysis was used to calculate the TTA required for a stifle angle of 135° measured using each of the three landmark sets.

Results: On average, the stifle angle determined by the Long Axes method differed by 18° from the stifle angle determined with the Kinematic method. The stifle angle determined using the Eminence method differed from that determined using the Kinematic method by three degrees. The use of the Long Axes of the tibia and femur as landmarks to determine a stifle angle resulted in 5 mm and 4 mm over-advancement of the tibial tuberosity compared to the use of Kinematic or Eminence landmark methods respectively.

Clinical significance: The method used to measure the stifle joint angle can influence the value of the required TTA advancement. This is an additional variable that should be considered during TTA planning and when comparing in vivo and in vitro studies.

Variation of tibial plateau geometry and cruciate ligament coordinates in six breeds of dogs

Objectives: The first aim of this study was to examine whether or not variations concerning the conformational characteristics of the proximal surface of the tibial plateau exist among six different dog breeds as well as within the same breed. The second aim of this study was to determine the coordinates of the cruciate ligaments.

Methods: One hundred and four tibias of 52 mature dogs from six different breeds were used. Photographs of the proximal surface of tibial plateau were taken, and measurements for the length, width and area of the tibial plateau, and the lateral and medial condyles were taken. In addition, the intercondylar width, height of Gerdy's tubercle, popliteal notch depth, and extensor groove depth were measured and recorded. The quotients from these measurements were calculated and compared amongst the dog breeds. The coordinates of the cruciate ligaments, according to the centre of tibial plateau, were also determined.

Results: Based on the calculated quotients, variations in the geometry of the tibial plateau geometry were common among the breeds. Within the same breed, on the other hand, length and width measurements of the tibial plateau were the least variable parameters among the other parameters examined. The cranial cruciate ligament was located in front of the surface centre of tibial plateau in all breeds. The position of cranial cruciate ligament was more variable in the craniocaudal direction than that observed in the mediolateral direction; this was the exact opposite of caudal cruciate ligament.

Clinical significance: The inter-breed variations of the quotients determined in the present study may facilitate attempts aimed to assess the risk factors of stifle joint injury and to design total knee prostheses.

Comparison of tibial anatomical-mechanical axis angle between predisposed dogs and dogs at low risk for cranial cruciate ligament rupture

The purpose of this prospective, radiographic, descriptive study was to compare measurements of tibial anatomical-mechanical axis angle (AMA-angle), tibial plateau angle (TPA), relative tibial tuberosity width (rTTW) and Z-angle from mediolateral radiographs of the tibia between two canine breeds (72 dogs) not predisposed to cranial cruciate ligament rupture (CCLR) and those from a consecutive series of 185 large dogs and 17 West Highland white terriers (WHWT) diagnosed with unilateral, surgically confirmed CCLR. Correlations among these measurements were determined, and levels of inter- and intra-observer variability among and within three observers for each measurement were established using Kendall's coefficient of concordance. Breed had a significant effect on AMA-angle. The median AMA-angle of the subject population of large dogs affected by CCLR was 2.80° (range 1.09°-5.21°); for the WHWT, it was 6.34° (range 5.68°-8.88°); and for the clinically normal dogs, it was 0.74° (range 0.00°-5.40°). In the CCLR group, AMA-angle and TPA were strongly correlated (r=0.745; p<0.0001). A receiver operating characteristic (ROC) curve analysis showed that an AMA-angle higher than 1.87° had a sensitivity of 0.941 (95% confidence interval [CI]: 0.898-0.966) and a specificity of 0.965 (95% CI: 0.919-0.987) for predicting CCLR and was more accurate than TPA, rTTW and Z-angle at predicting CCLR (p<0.0001). Good inter- and intra-observer agreement was found for all measurements. The highly significant difference in AMA-angle found between clinically normal dogs and dogs with CCL injury suggests that AMA-angle magnitude may be a clinically relevant predisposing factor for the development of canine CCLR.

Comparison of the proximal tibial angles between Labrador Retrievers and other dog breeds with and without cranial cruciate ligament rupture

ABSTRACTThe influence of the proximal tibia conformation in the rupture of the cranial cruciate ligament (CCL) in dogs is still controversial, especially in Labrador Retrievers. The aim of this study was to compare the angles of the proximal tibia between Labrador Retrievers and other large breeds of dogs, both groups with and without CCL rupture. Radiographic images of 64 stifle joints were obtained and divided into four groups of 16 images. Group 1 consisted of Labrador dogs without orthopedic disorders, group 2 consisted of Labrador dogs with CCL rupture, group 3 consisted of dogs of various large breeds without orthopedic disorders, and group 4 consisted of dogs of various large breeds with CCL rupture. The radiographs were performed in mediolateral projection with the stifle joint positioned at an approximate angle of 135°. The tibial plateau angle showed an overall average of 22.17°±4.20°, and there was no statistically significant difference between the groups. The patellar ligament angle in relation to the tibial plateau had a mean of 103°±4.20°, and there was a significant difference between groups 1 and 4. The patellar ligament angle in relation to the common tangent at the tibiofemoral contact point showed an average of 99.06°±6.08°, and there was no difference between the groups. The patellar ligament insertion angle had an overall average of 51.45°±5.06°, and there was a significant difference between the two groups of normal dogs and two groups of ruptured dogs. In conclusion, the tibial plateau angle, the patellar ligament angles and the patellar ligament insertion angle do not seem to be predisposing factors for rupture of the CCL in Labrador Retriever dogs. In general, there seems to be no relationship between the angles of the proximal tibia and the CCL rupture in dogs.

Comparison of the tibia plateau angle between small and large dogs with cranial cruciate ligament disease

OBJECTIVES

To compare the conformation of the proximal tibia evaluated on a medio-lateral radiograph between small and large dogs with cranial cruciate ligament disease (CCLD).

METHODS

Retrospective clinical study with dogs having radiographic evaluation and CCLD confirmed at surgery. The first group (n = 52) was comprised of dogs weighing less than 15 kg and the second group (n = 52) of dogs weighing more than 15 kg. The tibial plateau angle (TPA), the relative tibial tuberosity width (rTTW), and the Z angle were measured on preoperative radiographs with imaging measurement software. Linear mixed models were used to assess the effect of weight, age, sex, and neutered status on radiographic measurements and to estimate interobserver variabilities.

RESULTS

The small dog group had a greater TPA (30.1° ± 5.3; p <0.001 with a mean difference of 4.9° [95% CI: 3.8-6.0]) and Z angle (69.9° ± 5.6; p<0.001 with a mean difference of 6.1° ([95% CI: 4.9-7.4]) than the large dog group. Sex and neutered status further influenced the TPA and Z angle values. No significant effect was observed on the rTTW values. A strong correlation was found between the TPA and the Z angle (r = 0.61, p <0.001). Variances were not significantly different between observers. Overall the interobserver variability was low suggesting that agreement was good.

CLINICAL SIGNIFICANCE

Small dogs with CCLD have a steeper tibial plateau than large dogs with CCLD. Sex and neutered status also had an effect on some measured variables. This anatomical difference could influence the surgical technique, which may affect the outcome. The good interobserver agreement suggests the observer is unlikely to influence surgical planning.

Tibial anatomy in normal small breed dogs including anisometry of various extracapsular stabilizing suture attachment sites

OBJECTIVES

To investigate proximal tibial anatomy and its influence on anisometry of extracapsular stabilizing sutures in small dog breeds.

MATERIALS AND METHODS

Mediolateral radiographs of the femora, stifles, and tibiae of 12 small breed dogs were acquired with the stifles positioned at various angles. Measurements taken included tibial plateau angle (TPA), diaphyseal: proximal tibial angle (DPA), patellar tendon angle (PTA), Z-angle, relative tibial tuberosity width (rTTW), and the distance between six combinations of two femoral and three tibial extra-capsular stabilizing suture (ECS) attachment sites. Theoretical strain through stifle range-of-motion was recorded.

RESULTS

The TPA (32° ± 5.8°), DPA (10.2° ± 7.3°), PTA (103.7° ± 6.2°), and Z-angle (70.4° ± 9.0°) were positively correlated with one another (R >0.7), but none were correlated with rTTW (0.93 ± 0.10). The F2-T1 combination of ECS attachment sites had lowest strain for nine stifles. The shortest attachment site separation was at a stifle flexion of 50° for nine stifles. Proximal tibial anatomy measurements could not predict optimal attachment site combination, optimal stifle angle for suture placement, or ECS strain.

CLINICAL SIGNIFICANCE

There is individual variation in the optimal attachment site combination and stifle angle for suture placement, which may influence consistency of outcomes with ECS.

Comparative anatomy of the proximal tibia in healthy Labrador Retrievers and Yorkshire Terriers

OBJECTIVES

1) To provide specific quantitative data of tibial conformation in Labrador Retrievers and Yorkshire Terriers; 2) To compare the tibial conformation of these two breeds; and 3) To compare these data with previously reported data.

METHODS

Mediolateral radiographs of the stifle were obtained from 30 consecutive Labrador Retrievers and 30 consecutive Yorkshire Terriers with an angle of extension of 135°. The tibial plateau angle (TPA), the angle between the tibial plateau and the patellar tendon (PTA), the Z angle, the distal tibial axis/proximal tibial axis angle (DPA), and the relative tibial tuberosity width (rTTW) were measured and compared among the two breeds.

RESULTS

The breed had a significant effect on all of the measured variables (p <0.01): Labrador Retrievers had a lower TPA (25 ± 3° compared to 30 ± 4°), a lower Z angle (58.8 ± 3.2° compared to 69.2 ± 4.5°), a lower DPA (4.5 ± 2.3° compared to 10.8 ± 4.3°), and a lower rTTW (0.74 ± 0.1 compared to 0.86 ± 0.1) than Yorkshire Terriers. The PTA was greater in Labrador Retrievers compared to Yorkshire Terriers (106.9 ± 3.9° compared to 103.7 ± 6.5°). Four correlations were found to be significant: the DPA angle was correlated with the TPA, the Z angle, and the rTTW. The TPA was also correlated with the Z angle.

CLINICAL SIGNIFICANCE

The variation in tibial conformation between breeds should be taken into account when studying the role of each measured parameter in the pathology of cruciate disease. When the relevance of each of the aforementioned measured parameters is better understood, it may help determine the most appropriate surgical treatment.