Brian S. Beale

Radiographic outcome and complications of tibial plateau leveling osteotomy stabilized with an anatomically contoured locking bone plate

OBJECTIVE To evaluate the short-term clinical performance of an anatomically pre-contoured, locking plate in dogs undergoing tibial plateau leveling osteotomy (TPLO) for cranial cruciate ligament (CrCL) disease. STUDY DESIGN Prospective, multi-center clinical study. ANIMALS Dogs (n = 56) undergoing TPLO. METHODS Signalment and operative data were recorded. Preoperative, postoperative, and follow-up tibial plateau angle (TPA) were measured from radiographic images. Intraoperative and postoperative complications were recorded; the latter were categorized as minor if additional surgery was not necessary, and major if surgery was needed to resolve the complication. Bone healing was scored and change in tibial plateau angle (TPACH ) between postoperative and follow up radiographic images was calculated. RESULTS Mean (± SD) preoperative TPA was 28.6 ± 3.8°, and mean postoperative TPA was 4.8 ± 1.9°. Four intraoperative complications (7.1%) including 2 cases of intra-articular screw placement, 3 minor postoperative complications (5.4%), and no major or catastrophic postoperative complications occurred. Median bone healing grade was 4/4 (excellent union >75% healing). Mean TPACH was 0.15 ± 1.32°. CONCLUSIONS Use of this anatomically contoured, locking TPLO plate by experienced surgeons is associated with accurate tibial plateau leveling, reliably excellent bone union at follow-up exam, minimal TPACH , and a lower complication rate than previously reported. Confining contouring to the distal shaft of the plate ensures there is precise apposition to the tibial diaphysis and mitigates the risk of intra-articular screw placement.

Stabilization of the CORA based leveling osteotomy for treatment of cranial cruciate ligament injury using a bone plate augmented with a headless compression screw.

OBJECTIVE To report the effectiveness of a bone plate/headless compression screw (HCS) construct in preventing tibial plateau angle (TPA) shift postoperatively and to describe radiographic healing of the osteotomy. STUDY DESIGN Case series. ANIMALS Dogs (n = 31). METHODS Records of dogs diagnosed with cranial cruciate ligament (CCL) injury treated with the center of rotation of angulation (CORA) based leveling osteotomy (CBLO) stabilized with a bone plate augmented with a HCS were reviewed. Breed, age, weight, and gender were recorded. Radiographs were reviewed for determination of preoperative tibial plateau angle (PreTPA), postoperative TPA (PostTPA), patellar tendon angle (PTA) postoperatively, and TPA at final evaluation (FinalTPA). Difference between PostTPA and FinalTPA was used to define any TPA shift. Radiographic healing at final evaluation was graded based on a 5-point scale. RESULTS Mean time to final recheck was 88 days (range 49-237 days) with mean ± SD PreTPA = 28.6 ± 4.8°; PostTPA = 9.2 ± 2.2°; FinalTPA = 9.7 ± 2.6°; and TPA Shift = 0.52 ± 1.61°. There was no significant difference between PostTPA and FinalTPA (P = .084, power > 0.80). Mean postoperative PTA was 89.9 ± 1.7°. There were 2 implant related complications; 1 HCS migration and 1 HCS failure. CONCLUSION Stabilization of the CBLO using a bone plate augmented with a HCS was effective in maintaining PostTPA and achieving satisfactory radiographic healing.

Medium and Long Term Evaluation of Sliding Humeral Osteotomy in Dogs

OBJECTIVE To evaluate medium and long term effects of sliding humeral osteotomy (SHO) in dogs. STUDY DESIGN Prospective study. ANIMALS Dogs (n = 32). METHODS Data (2008-2010) collected from medical records included force plate data, radiographs, and a 15 question owner survey of dog soundness before SHO and at final evaluation. RESULTS All dogs except 2 exceeded their preoperative ground reaction forces in the operated limb and there was a statistically significant upward trend in ground reaction forces compared with the contralateral limb. Radiographic osteophytosis using the IEWG protocol had not progressed on the operated limb except in 1 dog. Most (90%) owners felt that lameness had diminished at the final evaluation compared with preoperative lameness. Ten dogs had postoperative complications; 6 were considered major, requiring further surgery. CONCLUSIONS SHO can be performed successfully in dogs to limit the radiographic progression of osteophytosis and increase use of the affected limb; however, the complication rate is high and further implant or technique modifications are needed to improve results.

Second‐look arthroscopic findings after CORA‐based leveling osteotomy

OBJECTIVE To describe the arthroscopic appearance of intra-articular structures mid-term (9 months) and long-term (>12 months) after CORA-based leveling osteotomy (CBLO). STUDY DESIGN Case series. ANIMALS Dogs (n = 41) with second-look arthroscopy of the stifle after CBLO for treatment of a cranial cruciate ligament (CCL) deficiency. Both stifles were re-evaluated (stifles n = 42) in 1 dog. METHODS Medical records of dogs that had second-look arthroscopy after CBLO were reviewed. Arthroscopic images of the femoral condyles were independently reviewed. The surgical report documented the integrity of menisci and articular cartilage of the tibial plateaus. RESULTS The population included 7 stifles with stable partial CCL tears, 35 stifles with complete CCL tears (n = 28), or incompetent partial CCL tears (n = 7). Median time to second look arthroscopy was 16 months (9-24 months) for stable partial tears. The CCL remained intact in 6 stifles. The Outerbridge score of the articular cartilage of the femoral condyles was as 0 (6) or 1 (1). The articular cartilage of the tibial plateaus appeared normal in all stifles. Median time to second look arthroscopy of stifles with complete tears was 12 months (range, 9-34 months). The caudal cruciate ligament was normal or mildly fibrillated. The appearance of the articular cartilage of the femoral condyles was scored as 0 or near normal (grade 1-2) in all dogs. The articular cartilage of the tibial plateaus appeared normal, except in 1 dog with grade 4 lesion. CONCLUSION CBLO results in minimal to no change in articular cartilage in at a median time of 14 months after surgery. Postoperative clinical lameness is often attributed to late onset meniscal pathology.

Fragmentation of the Medial Coronoid Process in Toy and Small Breed Dogs: 13 Elbows (2000–2012)

Fragmentation of the medial coronoid process (FCP) is an uncommon cause of thoracic limb lameness in toy and small breed dogs. Arthroscopic findings and treatment remains poorly described. The objective of this study was to describe the arthroscopic findings and short-term outcome following arthroscopic treatment in toy and small breed dogs with FCP. Medical records were retrospectively reviewed. Arthroscopic findings were available from 13 elbows (12 dogs). Outcome data ≥4 wk postoperatively were available for nine elbows. Owner satisfaction scores were available for 10 elbows. Common preoperative findings included lameness, elbow pain, and imaging abnormalities consistent with FCP. Displaced FCP was the most common FCP lesion identified. Cartilage lesions at the medial coronoid process were identified in 92.3% of elbows (n = 12), with a median Outerbridge score of 4 (range 1-5). Concurrent cartilage lesions of the medial humeral condyle were identified in 76.9% of elbows (n = 10). Seven of nine elbows had full or acceptable function postoperatively. Median owner outcome satisfaction was 91% (range 10-100). FCP should be considered a cause of thoracic limb lameness in toy and small breed dogs. Arthroscopy can be safely and effectively used to diagnose and treat FCP in these breeds.

Radiographic outcome and complications of tibial plateau leveling osteotomy stabilized with an anatomically contoured locking bone plate: Outcome of TPLO With a Locking Bone Plate

OBJECTIVE To evaluate the short-term clinical performance of an anatomically pre-contoured, locking plate in dogs undergoing tibial plateau leveling osteotomy (TPLO) for cranial cruciate ligament (CrCL) disease. STUDY DESIGN Prospective, multi-center clinical study. ANIMALS Dogs (n = 56) undergoing TPLO. METHODS Signalment and operative data were recorded. Preoperative, postoperative, and follow-up tibial plateau angle (TPA) were measured from radiographic images. Intraoperative and postoperative complications were recorded; the latter were categorized as minor if additional surgery was not necessary, and major if surgery was needed to resolve the complication. Bone healing was scored and change in tibial plateau angle (TPACH ) between postoperative and follow up radiographic images was calculated. RESULTS Mean (± SD) preoperative TPA was 28.6 ± 3.8°, and mean postoperative TPA was 4.8 ± 1.9°. Four intraoperative complications (7.1%) including 2 cases of intra-articular screw placement, 3 minor postoperative complications (5.4%), and no major or catastrophic postoperative complications occurred. Median bone healing grade was 4/4 (excellent union >75% healing). Mean TPACH was 0.15 ± 1.32°. CONCLUSIONS Use of this anatomically contoured, locking TPLO plate by experienced surgeons is associated with accurate tibial plateau leveling, reliably excellent bone union at follow-up exam, minimal TPACH , and a lower complication rate than previously reported. Confining contouring to the distal shaft of the plate ensures there is precise apposition to the tibial diaphysis and mitigates the risk of intra-articular screw placement.

Biomechanical and computational evaluation of two loading transfer concepts for pancarpal arthrodesis in dogs

OBJECTIVE To evaluate 2 plate designs for pancarpal arthrodesis and their effects on load transfer to the respective bones as well as to develop a computational model with directed input from the biomechanical testing of the 2 constructs. SAMPLE Both forelimbs from the cadaver of an adult castrated male Golden Retriever. PROCEDURES CT imaging was performed on the forelimb pair. Each forelimb was subsequently instrumented with a hybrid dynamic compression plate or a castless pancarpal arthrodesis plate. Biomechanical testing was performed. The forelimbs were statically loaded in the elastic range and then cyclically loaded to failure. Finite element (FE) modeling was used to compare the 2 plate designs with respect to bone and implant stress distribution and magnitude when loaded. RESULTS Cyclic loading to failure elicited failure patterns similar to those observed clinically. The mean ± SD error between computational and experimental strain was < 15% ± 13% at the maximum loads applied during static elastic loading. The highest bone stresses were at the distal extent of the metacarpal bones at the level of the screw holes with both plates; however, the compression plate resulted in slightly greater stresses than did the arthrodesis plate. Both models also revealed an increase in bone stress at the proximal screw position in the radius. The highest plate stress was identified at the level of the radiocarpal bone, and an increased screw stress (junction of screw head with shaft) was identified at both the most proximal and distal ends of the plates. CONCLUSIONS AND CLINICAL RELEVANCE The FE model successfully approximated the biomechanical characteristics of an ex vivo pancarpal plate construct for comparison of the effects of application of different plate designs.