Extra-articular absorbable suture stabilization of coxofemoral luxation in dogs

OBJECTIVE: To evaluate the effectiveness of an extra-articular surgical technique using absorbable suture material for the stabilization of traumatic coxofemoral luxation in dogs. STUDY DESIGN: Prospective, clinical study. ANIMALS: Fourteen client-owned dogs with recent and long-standing traumatic coxofemoral luxation (13 craniodorsal and 1 ventral). METHODS: Coxofemoral luxations were surgically reduced and maintained in place with an extra-articular iliofemoral multifilamentous absorbable suture (3 to 6 strands of 2 USP Polyglactin 910). No external support was employed, and all the dogs were encouraged to use the affected limb postoperatively. The average time of clinical and radiographic follow-up was 11.6 +/- 6.3 months (from 2 to 22 months). RESULTS: During the follow-up period, no reluxations occurred and no complications associated with the surgical technique were identified. The dogs started bearing weight from 1 to 10 days after the surgery (mean, 4.3 +/- 2.9 days) and the period of lameness ranged from 7 to 30 days (20 +/- 8.6 days). At the final clinical examination, the dogs did not demonstrate any lameness or pain during passive flexo-extension movements, and there was no significant limitation of the range of motion. CONCLUSION: Extra-articular stabilization with multifilamentous absorbable sutures is a simple, effective method of treatment for acute and chronic coxofemoral luxation. The absorbable material used is strong enough to maintain articular stability during the period of scar tissue formation even in large-breed dogs. CLINICAL RELEVANCE: Absorbable sutures avoid the possible complications related to the use of nonabsorbable material and seem to be sufficient to maintain articular stability during the capsular healing process.     

Toggle rod stabilization for treatment of hip joint luxation in dogs: 62 cases (2000-2005)

OBJECTIVE: To determine outcome of open toggle rod stabilization in dogs with luxation of the hip joint. Design-Retrospective case series. ANIMALS: 62 dogs. PROCEDURES: Information on signalment, surgical procedure, and postoperative care was obtained from the medical records. A questionnaire was sent to all owners to solicit follow-up information. RESULTS: The distribution for time between luxation and surgery was bimodal, with 24 (39%) dogs examined < or = 2 days after injury and 23 (37%) examined > 7 days after injury. Postoperative complications developed in 16 of the 62 (26%) dogs, with complications developing within 1 week after surgery in 10 of the 16. The most common complication was reluxation, which occurred in 7 dogs. Dogs in which surgery time was < 2 hours were significantly less likely to have a reluxation (2/40 [5%]) than were dogs in which surgery time was > or = 2 hours (5/22 [23%]). When asked to rate current limb function (0 = no lameness and 5 = non-weightbearing lame) a minimum of 6 months after surgery, 23 of 27 (85%) owners indicated a score of 0 or 1. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the present study suggest that toggle rod stabilization is an effective treatment for hip joint luxation in dogs. However, complications, particularly reluxation, were common.     

Biomechanical analysis of suture anchors and suture materials used for toggle pin stabilization of hip joint luxation in dogs

OBJECTIVE: To compare in vitro mechanical properties of toggle pins and toggle rods used as suture anchors and of 3 suture materials (50-lb monofilament polybutester, No. 5 braided polyester, and 5-mm woven polyester) commonly used as prosthetic ligaments in the repair of hip joint luxation in dogs. SAMPLE POPULATION: Femoropelvic specimens from the cadavers of 18 dogs. PROCEDURE: Suture anchors were compared by use of pullout tests. Suture materials were compared by use of monotonic and cyclic tensile tests; cyclic tensile tests were performed with the suture placed over the edge of an aluminum bar to simulate the edge of the femoral bone tunnel. In vitro mechanical properties of the ligament of the femoral head were determined by use of monotonic tensile tests, using bone-ligament-bone cadaveric specimens. The in vitro mechanical properties of the acetabulum-ligament-femur complex and of this complex following rupture of the ligament and stabilization with a toggle rod and 5-mm woven polyester were determined by use of compression tests that simulated weight-bearing. RESULTS: Mechanical properties of the toggle rod were not significantly different from those of the toggle pin. Woven polyester had the longest fatigue life in cyclic testing. Hip joints stabilized with a toggle rod and woven polyester had less than half the strength in vitro of intact joints. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that a toggle rod or toggle pin can be used for stabilization of hip joint luxations in dogs. Of the materials tested, braided polyester had the best in vitro mechanical properties.     

Reduction of humeroulnar congenital elbow luxation in 8 dogs by using the transarticular pin

The purpose of this study was to evaluate the clinical and radiographic outcome in 8 dogs of surgical reduction of congenital humeroulnar luxation by using the transarticular pin. Five cases were bilateral and 3 were unilateral, for a total of 13 elbows. The treatment was performed in animals between 45 and 150 days of age. Articular stabilization was achieved by using a transarticular pin driven from the caudal aspect of the olecranon into the body of the humerus or into the distal condyle and distal metaphysis of the humerus. The follow-up period was between 1 and 19 months. There were 5 postsurgical reluxations, 3 related to the insertion of the pin into the humeral condyle and 2 related to the insertion into the humeral body. These animals needed further surgery. Six animals showed near normal return to limb function and 2 had lameness. We conclude that the use of the transarticular pin is an effective and simple method for the treatment of humeroulnar congenital elbow luxation.     

Volume of the ligamentum capitis femoris in osteoarthritic hip joints of adult dogs

Ventrodorsal pelvic radiographs were made of 32 adult dogs under general anaesthesia. The hip joints were evaluated according to the severity of osteoarthritic changes graded as 0, 1, 2 or 3. The dogs were euthanased, the hip joints opened and the ligamentum capitis femoris dissected out in toto. The volume of each ligament was determined using a water displacement technique and the mean volume compared to the four radiographic grades of osteoarthritis. There was an inverse correlation (r = -0.75) between the mean volume of the ligamentum capitis femoris and the increasing severity of osteoarthritis as assessed by radiography. The results confirmed the crucial role of radiography in the clinical evaluation of hip dysplasia and osteoarthritis in the adult dog. Assessment of the volume of the ligamentum capitis femoris revealed that it is an important tool for research in canine hip dysplasia and osteoarthritis.     

Evaluation of risk factors for luxation after total hip replacement in dogs

OBJECTIVE: To identify risk factors for luxation after canine total hip replacement (THR). STUDY DESIGN: Retrospective study. SAMPLE POPULATION: 256 client-owned dogs that underwent THR. METHODS: Patient data surveyed included signalment, body weight, diagnosis, prior hip surgery, implant size, intraoperative complications, and angle of lateral opening of the acetabular component. RESULTS: Postoperative complications were recorded in 20 cases (7.8%). The most common complication was dorsal luxation which occurred in 12 dogs (4.7%). The interval between joint replacement and luxation ranged from 1 to 116 days (mean, 44 days). In 1 case, luxation was attributable to failure of the repair of an intraoperative fracture of the greater trochanter. Excluding this case, the mean angle of lateral opening in those dogs that sustained luxation was 62 degrees (range, 46 degrees - 75 degrees). The mean angle of lateral opening overall was 48 degrees (range, 18 degrees - 76 degrees). The angle of lateral opening was the only factor that had a statistically significant effect on whether luxation occurred (P = .035). Acetabular revision, performed primarily to reduce the angle of lateral opening, was performed in 8 dogs and successfully prevented subsequent luxation. CONCLUSION: Luxation of the prosthesis is substantially under the control of the surgeon. It is recommended that the acetabular cup be inserted at an angle of lateral opening of 35 degrees to 45 degrees. In those cases of THR luxation in which an inappropriate angle of lateral opening is identified, acetabular revision arthroplasty generally results in a good clinical outcome.     

四种手术方法治疗犬髋关节脱位的效果比较

为探讨犬髋关节脱位几种手术方法的实际疗效及其优缺点,选择健康家犬制作髋关节脱位模型,分别施行人造圆韧带植入术、髋关节囊外固定术、股骨头切除术和髋关节囊单纯缝合术,术后对实验犬术肢的运动机能、负重耐力及髋关节结构等进行了观察。实验表明,以上各种手术对犬的年龄或髋关节结构各有要求,其中以股骨头切除术疗效肯定、适应范围广,而人造圆韧带植入术的疗效最差。     

Contribution of the xenograft bone plate-screw system in lumbar transpedicular stabilization of dogs: an in-vitro study

We performed biomechanical comparison of a xenograft bone plate-screw (XBPS) system for achieving cadaveric lumbar transpedicular stabilization (TS) in dogs. Twenty dogs'' cadaveric L_2-4 lumbar specimens were harvested and their muscles were removed, but the discs and ligaments were left intact. These specimens were separated to four groups: the L_2-4 intact group as control (group I, n = 5), the L₃ laminectomy and bilateral facetectomy group (LBF) (group II, n = 5), the LBF plus TS with metal plate-screw group (group III, n = 5) and the LBF plus TS with XBPS group (group IV, n = 5). Five kinds of biomechanical tests were applied to the specimens: flexion, extension, left-right bending and rotation. The averages of the 16 stiffness values were calculated and then these were statistically analyzed. The statistical results show that the XBPS system contributes spinal stability and this system can be a good choice for achieving TS.     

Use of an ipsilateral vascularized ulnar transposition autograft for limb-sparing surgery of the distal radius in dogs: an anatomic and clinical study

OBJECTIVE: To develop a surgical technique for using the distal aspect of the ulna as a transposition autograft in a distal radial defect and to assess patency of vascular supply and viability of the distal ulna in a heterotopic position. STUDY DESIGN: Cadaveric study and clinical cases. ANIMALS: Twenty-two normal canine thoracic limbs; 3 dogs with distal radial osteosarcoma. METHODS: The arteries and veins of 12 limbs were injected with latex. Barium sulfate suspension was injected into the brachial artery of 10 other limbs after removal of the distal radius only (n = 2), ulna transposition (UT) (n = 6), or no procedure (n = 2). The distal ulna grafts were then harvested and decalcified in formic acid. The grafts were cut into 3-5 mm transverse sections and radiographed with a nonscreen film system to determine filling of intramedullary vessels with barium suspension. UT was performed in 3 dogs with distal radial osteosarcoma. Bone scintigraphy was performed 2-7 days after surgery to assess viability of the transposed ulna graft. RESULTS: Angiography confirmed patency of the caudal interosseous artery in all but 2 limbs in which the UT technique was performed; however, barium-filled vessels were identified in the medullary cavity of all ulnar grafts. Scintigraphy confirmed graft viability in the 3 dogs, all of which had good to excellent limb function. CONCLUSIONS: The distal aspect of the canine ulna can be used as a vascularized transposition autograft to replace distal radial defects, and viability can be maintained. CLINICAL RELEVANCE: The UT technique appears to be an acceptable limb-sparing technique for dogs with tumors of the distal aspect of the radius.     

Changes in the hip joint of the dog following traumatic luxation

A report is presented, on the changes occurring in the hip joints of thirty-four dogs, following treatment of traumatic coxofemoral luxation.
The animals were examined from 2 weeks to 7 years after treatment of the original injury. Twenty of the hips re-examined showed radiographic and/ or clinical abnormalities. These changes are divided into three classes, in accordance with the presence of persistent coxofemoral luxation and consequent pseudoarthrosis (or false joint) formation; coxofemoral arthritis; and asymptomatic exostosis of the ilium.
Résumé. L'auteur présente des observations concernant les modifications observées au niveau de la hanche chez 34 chiens traités pour une luxation coxo-fémorale traumatique. Les animaux avaient été examinés de 2 semaines à 7 ans après le traitement du traumatisme initial. Dans 20 cas on a trouvé des modifications cliniques ou radiologiques ou les deux à la fois au cours des nouveaux examens. Ces modifications étaient de trois sortes: persistance de la luxation coxofémorale avec formation ultérieure d'une pseudarthrose (fausse articulation); arthrite coxofémorale; exostose asymptomatique de l'os iliaque.
Zusammenfassung. Ein Bericht über die in den Hüftgelenken von 34 Hunden nach der Behandlung traumatischer coxofemoraler Luxation eintretenden Veränderungen wird vorgelegt.
Die Tiere wurden 2 Wochen bis 7 Jahre nach der Behandlung der Verletzung untersucht. Zwanzig der wiederuntersuchten Hüften zeigten radiographische und bzw. oder klinische Anoxmalitäten. Je nach dem Vorhandensein persistierender coxofemoraler Luxation und sich daraus ergebender Pseudoarthrose, d.h. Neubildung eines Gelenks an falscher Stelle, coxofemoraler Arthritis und asymptomatischer Exostose des Iliums wurden die Veränderungen in drei Klassen cingeteilt.     

Pericapsular hip desensitization in dogs: a cadaveric study and case series

ObjectiveTo develop and assess the efficacy of an ultrasound (US)-guided pericapsular hip desensitization (PHD) technique in dogs.Study designProspective, randomized, anatomical study and a case series.AnimalsA total of 30 healthy dogs, eight canine cadavers and seven dogs with hip osteoarthritis.MethodsAfter studying the US anatomy of the medial aspect of the coxofemoral joint and determining an acoustic window to perform an US-guided PHD in healthy dogs, the US-guided PHD was performed bilaterally in canine cadavers. A low [(LV) 0.1 mL kg^–1] and high [(HV) 0.2 mL kg^–1] volume of dye was injected per hip on each cadaver. The staining of the pericapsular nerves was assessed by anatomical dissection, and comparison between LV and HV was assessed using Fisher’s exact test. Then, the US-guided PHD was performed using a triamcinolone–bupivacaine solution in dogs with hip osteoarthritis. Dynamic pain response was assessed before and after injection. The canine brief pain inventory (CBPI) questionnaire was used to assess treatment efficacy and duration.ResultsThe US-guided PHD could be performed by inserting the needle between the iliopsoas muscle and the periosteum of the ilium. The articular branches of the femoral and obturator nerves were stained in all cadavers using both volumes. The main femoral nerve was never stained, but the main obturator nerve was stained in 37.5% and 100% of injections using LV and HV, respectively (p = 0.026). Treated animals showed decreased dynamic pain response after the injection. Compared with baseline, CBPI scores were reduced by ≥ 50% for ≥ 12 weeks in all but one dog.Conclusions and clinical significanceThe US-guided PHD with both 0.1 and 0.2 mL kg^–1 volumes stained the articular branches of the femoral and obturator nerves in canine cadavers and was associated with clinical improvement in dogs with hip osteoarthritis.     

Acetabular component orientation as an indicator of implant luxation in cemented total hip arthroplasty

OBJECTIVE: To determine the sensitivity and specificity with which acetabular component angles of inclination and version could be used, alone or in combination, to predict luxation of cemented total hip arthroplasties (THA). STUDY DESIGN: Comparison of retrospectively selected cases and controls SAMPLE POPULATION: All THA performed at the University of Florida between 1991 and 1998 with the BioMedtrix system and for which at least 2 months of radiographic follow-up were available. All THA performed at the University of Georgia with the BioMedtrix system which subsequently luxated. METHODS: Acetabular component inclination angle (IA) and acetabular version angle (VA) were determined for each THA. Data were grouped according to outcome - luxation or no luxation - with the luxated cases from the 2 institutions pooled. Receiver operator characteristic (ROC) analysis was used to evaluate decision rules for using IA and VA as tests for detecting postoperative luxation. Sensitivity and specificity for luxation and 95% confidence bounds were computed with selected values of IA and VA as cut-points. RESULTS: The nonluxation group consisted of 68 THA with a median follow-up time of 5 months (range, 2-60 months). The luxation group consisted of 12 THA with a mean time to luxation of 36 days. The nonluxation group had a mean +/- standard deviation (SD) IA and VA of 40.3 degrees +/- 8.9 degrees and 71.1 +/- 13.6 degrees, respectively, whereas the luxation group had a mean +/- SD IA and VA of 34.7 degrees +/- 12.6 degrees and 72.9 degrees +/- 16.6 degrees, respectively. An IA cut-point of 37.8 degrees achieved 58.3% sensitivity and 57.4% specificity. A VA cut-point of 73 degrees achieved 75.0% sensitivity and 51.5% specificity. IA and VA considered simultaneously achieved a 50.0% sensitivity and 88.2% specificity. CONCLUSIONS AND CLINICAL RELEVANCE: ROC analysis indicated that both IA and VA considered individually or simultaneously were poor indicators of luxation. Although extreme values of IA may predict luxation with high specificity, the potential for luxation cannot be excluded based on apparently appropriate values of IA and VA. The results of this study also indicate that a successful outcome is possible with a wide range of acetabular component positions.     

Evaluation of minimally invasive surgical reduction of sacroiliac luxation in toy breed dogs: a cadaver study

BackgroundMinimally invasive surgery (MIS) technique of sacroiliac luxation in toy breed dogs using cannulated screws has not been described.ObjectivesThe purpose of this study was to evaluate the effectiveness of pelvic canal recovery, the reproducibility of successful surgery outcomes, and the acceptable difficulty of the procedure in MIS of sacroiliac luxation in toy breed dogs.MethodsMIS using 2.3-mm cannulated screws was demonstrated in 12 toy breed dog cadavers with sacroiliac luxation artificially induced. Pre and postoperative radiographs were used to evaluate the pelvic canal diameter ratio (PCDR), hemipelvic canal width ratio (HCWR), and reduction rate. Dorsoventral angle (DVA) and craniocaudal angle (CCA) of the inserted screw were obtained postoperative computed tomographic scan.ResultsThe statistically significant difference between the mean pre and postoperative PCDR was found (1.10 ± 0.12 and 1.26 ± 0.11, respectively; p = 0.002), and the mean HCWR close to 1.0 meaning symmetric pelvis also was obtained (0.97 ± 0.07). The mean DVA and CCA were 2.26° ± 1.33° and 2.60° ± 1.86°, respectively.ConclusionsMIS of sacroiliac luxation using 2.3-mm cannulated screws is applicable to toy breed dogs with acceptable difficulty.