Closing Wedge Ostectomy 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.

Objective and owner-reported outcomes after modified cranial closing wedge ostectomy: a case series

Immediate and longer-term outcomes of a cranial closing wedge ostectomy variant for management of canine cranial cruciate ligament disease were assessed in this single-center retrospective consecutive study. Records and radiographs were retrieved and assessed by three independent observers to evaluate tibial plateau angle, anatomical-mechanical axis angle, tibial tuberosity distalization, and mechanical axis length before and after surgery. Kinetic gait analysis and owner questionnaires were used to assess clinical outcomes. Seventeen stifles from fifteen dogs were evaluated radiographically. Mean error from target tibial plateau angle was 0.4 degrees. Anatomical-mechanical axis angles reduced from mean 2.9 degrees preoperatively to mean − 0.9 degrees postoperatively. Tibial tuberosity distalization was mean 5.0% of mechanical axis length, and mean reduction in mechanical axis length was 0.1%. Increased tibial plateau angles were noted in 8/17 stifles, with a mean of 9.6 degrees at short-term follow-up. Major complications were observed in 9/17 stifles. Long term follow-up (mean 832 days) was obtained with gait analysis in 8/15 dogs and with questionnaire in 11/15. Most dogs (9/11) were weakly to moderately affected by osteoarthritis symptoms. All values for peak vertical force and vertical impulse normalized to body weight exceeded local lower reference limits for normal dogs, indicating acceptable limb use. Satisfactory immediate and long-term clinical outcomes appear to be possible with this technique, but the high incidence of shorter-term complications may caution against the technique or the fixation and management described here.

Predicting tibial plateau angles following four different types of cranial closing wedge ostectomy.

To investigate how tibial long axis (TLA) shift affects the postoperative tibial plateau angle (TPA) in four cranial closing wedge ostectomy (CCWO) techniques. In silico study. A total of 15 client-owned dogs. Computed tomography (CT) scans of 15 client-owned dogs were reviewed using an open-source 3D computer graphics editor. Each computer-generated 3D tibia model underwent a CCWO, with cranial cortex alignment, in 10° increments up to 70° using each of the four previously described techniques. The TLA shift, TPA and mechanical tibial length (mTL) were calculated, using trigonometry, for each model. Equations for predicting final TPA were generated with linear regression. A total of 433 3D computer generated tibial models were analyzed. With each technique, the TPA varied in a linear fashion within the studied range of wedge angles. The TLA shift and tibial shortening magnitude varied between the four different CCWO techniques, with maximum mTL reduction of ranging from 7.5% to 40.9%. All predicted TPAs using the generated equations were within the target range of 4-6°. A linear relationship between ostectomy wedge angle and TPA correction was observed in this study, which allowed for generation of accurate corrective equations. These results allow extrapolation of the wedge angle required to reach a postoperative TPA of 5°, by considering the TLA shift. The use of the generated corrective equations may thus increase CCWO planning precision.

Morphologic impact of four surgical techniques to correct excessive tibial plateau angle in dogs: A theoretical radiographic analysis.

To determine morphologic differences between four tibial osteotomy techniques used to correct excessive tibial plateau angle (eTPA). Retrospective radiographic analysis. Sixteen dogs (27 tibias) with eTPA. Virtual corrections of eTPA were performed on sagittal plane radiographs of canine tibia using four tibial osteotomy techniques and categorized into respective groups. Group A represented the center of rotation of angulation (CORA)-based leveling osteotomy (CBLO) and coplanar cranial closing wedge ostectomy (CCWO), Group B the tibial plateau leveling osteotomy (TPLO) and CCWO, Group C the modified CCWO (mCCWO), and Group D the proximal tibial neutral wedge osteotomy (PTNWO). Pre- and post-correction TPA, tibial length and mechanical cranial distal tibial angle (mCrDTA) were measured and compared. Mean TPA prior to correction was 42.67 ± 6.1°. Post-correction mean TPAs were 10.47 ± 2.1°, 6.77 ± 1.6°, 4.76 ± 1.5°, and 7.09 ± 1.3° for Groups A, B, C, and D, respectively. TPA correction accuracy in Groups A and D varied least from target TPAs. Tibial shortening was documented in Group B in contrast to other groups. The greatest mechanical axis shift was identified in Group A. Each technique achieved TPA < 14° despite having different effects on tibial morphology including alteration of tibial length, mechanical axis shift and variation in correctional accuracy. Despite all methods being able to correct eTPA, the choice of technique will affect morphology in unique ways and should be considered prior to surgery to consider the implications in a given patient.

Radiographic Comparison of Virtual Surgical Corrective Options for Excessive Tibial Plateau Angle in the Dog.

The main aim of this study is to compare the impact of six proximal tibial osteotomies on the geometry and alignment of tibias with and without excessive tibial plateau angle (TPA). Mediolateral radiographs of 30 canine tibias were divided into three groups (n = 10/group): moderate TPA (≤34 degrees), severe TPA (34.1-44 degrees) and extreme TPA (>44 degrees). Six proximal tibial osteotomies were simulated on each tibia using orthopaedic planning software: cranial closing wedge ostectomy (CCWO), modified CCWO (mCCWO), isosceles CCWO (iCCWO), neutral isosceles CCWO (niCCWO), tibial plateau levelling osteotomy with CCWO (TPLO/CCWO) and coplanar centre of rotation of angulation-based levelling osteotomy (coCBLO). All tibias were reduced to a standard target TPA. Pre- and postoperative measurements were obtained for each virtual correction. Compared outcome measures included tibial long axis shift (TLAS), cranial tibial tuberosity shift (cTTS), distal tibial tuberosity shift (dTTS), tibial shortening and osteotomy overlap. Across all TPA groups, TPLO/CCWO had the lowest mean TLAS (1.4 mm) and dTTS (6.8 mm); coCBLO had the largest TLAS (6.5 mm) and cTTS (13.1 mm); CCWO had the largest dTTS (29.5 mm). CCWO had the largest degree of tibial shortening of 6.5 mm, while mCCWO, niCCWO and coCBLO resulted in minimal tibial lengthening (1.8-3.0 mm). These trends were generally conserved across different TPA groups. All findings had a p-value less than 0.05. mCCWO balances moderate alterations to tibial geometry while preserving osteotomy overlap. The TPLO/CCWO has the least effect on tibial morphology alteration, whereas the coCBLO results in the largest alteration.

Reported accuracy of cranial closing wedge ostectomy variants for management of canine cranial cruciate ligament insufficiency: A systematic review and meta-analysis

Concerns have been raised about the predictability of achieving appropriate tibial plateau angles (TPA), the occurrence of axis shift and tibial length reduction following cranial closing wedge ostectomy (CCWO). The primary objective of this review was to quantify typical errors in achieving target TPA with CCWO, with secondary objectives of assessing axis shift and length reduction. Retrospective or prospective studies of CCWO used as the primary treatment, from any date and in English, were eligible for inclusion. Searches were performed in EMBASE, Ovid MEDLINE, Agricola, Scopus, Web of Science, and CAB abstracts. Risk of bias was assessed, and data were screened for outliers and influential cases. Extracted data from 11 included studies were tabulated and underwent meta-analysis using R. Mean errors in TPA after CCWO ranged from − 0.6–2.9°, indicating the possibility of both under- and over-correction depending on the selected technique. Errors were relatively consistent for technique subgroups. Mean axis shifts ranged from 3.4° to 5.2°, and length reduction ranged from 0.4% to 3.2% of initial length, based on 6/11 and 3/11 studies, respectively. Data had high heterogeneity, many studies had small populations, and reporting standards were inconsistent. Concerns about the predictability of postoperative TPA may be overstated. With the limited data available, limb shortening does not appear to be a clinically important consideration. Axis shift will occur to varying degrees and must be considered during CCWO planning, as it influences the postoperative TPA. Careful choice of CCWO technique may allow clinicians to reliably achieve predictable TPA values.

Corrective Osteotomy in a Dog to Address Increased Distal Femoral Procurvatum Ascribed to a Distal Femoral Salter-Harris Type V Injury

AbstractIncreased distal femoral procurvatum has been reported sporadically in dogs following malunion of Salter-Harris type I, II, and III fractures of distal femur. The resultant increased procurvatum can be poorly tolerated because of subsequent loss of stifle extension. This case report represents a dog with the increased procurvatum of the distal femur ascribed to a previous Salter-Harris type V injury. Surgical planning and successful outcome following the corrective procedures have been documented. A 6.5-month-old fox-terrier presented with a persistent weight bearing left pelvic limb lameness, 2 months after being hit by a car. The predominant orthopaedic finding was a 20-degree decrease in left stifle extension. Radiographic and computerized tomography evaluation revealed premature eccentric closure of the left distal femoral physis ascribed to a previous Salter-Harris type V injury. The left femoral procurvatum was 30 degrees. The left tibial plateau angle was increased by 11.5 degrees compared with the right. The femoral deformity was characterized, and a corrective procedure was planned using Paley's centre of rotation of angulation methodology. A cranial closing wedge ostectomy of the left distal femur was performed and stabilized using a locking plate. Proximal tibial epiphysiodesis was also performed to reduce the tibial plateau slope. Union of the osteotomy site and reduction in tibial plateau angle by 5.4 degrees were documented 50 days after surgery with a good functional outcome.

Comparison of patellar position and moment arm between tibial plateau leveling osteotomy and cranial closing wedge ostectomy: An ex vivo study.

Tibial plateau leveling osteotomy (TPLO) and cranial closing wedge ostectomy (CCWO) are common treatments for cranial cruciate ligament disease. These two techniques mainly differ in whether the proximal tibial fragment contains the attachment site of the patellar ligament. Currently, no reports compare how these techniques affect the patellofemoral joint. This ex vivo study aimed to compare the effects of TPLO and CCWO on the patellar position and moment arm in healthy Beagles. TPLO and CCWO were performed on each stifle in six cadavers of Beagles. Pre- and postoperative mediolateral radiographs with the stifle angle at approximately 90° were obtained. The modified Blumensaat index (MBI), patellar ligament length to patella length ratio (PLL:PL), and patellar moment arm (PMA) were measured in each radiograph. Mixed-model multiple regression analyses for the MBI, PLL:PL, and PMA, with the surgical procedure as the independent variable, were then performed. The joint angle was included as an independent variable for MBI and PMA. The PLL:PL was decreased after TPLO. Additionally, the PLL:PL after TPLO was significantly lower than that after CCWO. The MBI decreased with flexion. Postoperative MBI values were reduced for both procedures, with lower values after CCWO than after TPLO. The PMA values decreased with flexion. Postoperative values for both methods were reduced in the PMA, with the values being lower after CCWO than after TPLO. Both TPLO and CCWO affect the patellofemoral joint. Compared with TPLO, CCWO produced more excellent downward traction on the patella. Therefore, CCWO may be used to correct the patellar alta and treat cranial cruciate ligament disease.

Stifle hyperextension identified in a dog with an excessively negative tibial plateau angle and a grossly intact cranial cruciate ligament following inappropriate cranial closing wedge ostectomy

AbstractA cross breed dog was examined due to an abnormal right pelvic limb gait following cranial closing wedge ostectomy surgery. Gait evaluation revealed stifle hyperextension during the stance phase of the gait. Manipulation of the stifle revealed no cranial or caudal drawer and no cranial tibial thrust. Radiographs showed complete healing of the proximal tibial osteotomy, with a tibial plateau angle (TPA) of –14°. Computed tomography showed 20° of external tibial torsion on the right pelvic limb. A mini‐medial stifle arthrotomy revealed no gross damage to the cruciate ligaments and intact menisci. A cranial opening wedge osteotomy of 17° was performed and the torsional alignment corrected, after which the tibia was stabilised with orthogonal plates and an intramedullary pin. The postoperative radiographs confirmed a satisfactory TPA of 3° and normal tibial alignment. At 6 months follow‐up, a video record revealed normal right pelvic limb gait.

Deep Digital Flexor Contracture following Combined Tibial Plateau Levelling Osteotomy and Cranial Closing Wedge Ostectomy: A Case Report in a Dog

AbstractThis case report describes the use of a Z-plasty tenotomy and anastomosis to surgically lengthen the deep digital flexor (DDF) tendons of digits 2 to 5 of the pelvic limb in a 6-year-old male castrated Greyhound. The procedure was used to treat contracture of this tendon complex which developed after a series of complications secondary to proximal osteotomies utilized for the treatment of cranial cruciate ligament rupture. The dog was evaluated for lameness associated with left cranial cruciate ligament rupture and excessive tibial plateau slope; accordingly, a combined tibial plateau levelling osteotomy and cranial closing wedge ostectomy was performed. Postoperatively, the dog developed substantial DDF tendon contracture that led to severe digital hyperflexion and contributed to a non-weight bearing lameness. The dog received intensive rehabilitation therapy but failed to substantially improve; therefore, all of the weight-bearing left hindlimb DDF tendons were lengthened with a Z-plasty tenotomy and anastomosis followed by further rehabilitation. Follow-up evaluation 44 months postoperatively documented mild, intermittent left hindlimb lameness on gait observation and confirmed success of the Z-plasty procedure via ultrasonographic evaluation. Conservative treatment alone was unsuccessful in managing DDF tendon contracture in this dog. Z-plasty tenotomy and anastomosis of the DDF tendon allowed for return-to-acceptable function in this case.

Tibial Plateau Leveling Following Tibial Tuberosity Advancement: A Case Series.

Persistent stifle instability is a recognized complication following tibial tuberosity advancement techniques (TTAT). The aim of this study is to report the feasibility and outcome of tibial plateau leveling techniques (TPLT) to treat dogs with persistent lameness, suspected to be secondary to persistent stifle instability, following (TTAT). Medical records of dogs presented for persistent lameness after TTAT were reviewed. Preoperative data included orthopedic examination, lameness score and radiographs. Inclusion criteria included performance of a surgery to address persistent lameness and suspected instability. Short-term follow up data included orthopedic examination and radiographs of the stifle. Long-term follow up was based on postoperative Liverpool Osteoarthritis in Dogs (LOAD) questionnaire. Seven dogs were included in the study. Mean subjective preoperative lameness score was 3 ± 1.53. Mean preoperative patellar ligament angle relative to the tibial plateau (PLATP) was 94° and mean tibial plateau angle (TPA) was 28°. Six dogs had tibial plateau leveling osteotomy and one had modified cranial closing wedge ostectomy. Mean postoperative PLATP was 79° and mean TPA was 5°. Mean subjective lameness score at follow up was 0.57 ± 0.49. Minor complications were present in 2 dogs and major complication in 1 dog. Mean LOAD questionnaire score was 6.6/52. TPLT can be performed after TTAT and may improve clinical function and stability in these cases in which persistent instability is suspected.

Double-cut center of rotation of angulation–based leveling osteotomy for treatment of cranial cruciate ligament deficiency and excessive tibial plateau angle secondary to growth anomaly in two dogs

A 4-year-old female Staffordshire Bull Terrier (dog 1) and a 6-year-old male Yorkshire Terrier (dog 2) were evaluated because of left pelvic limb lameness. Both dogs had a partial rupture of the left cranial cruciate ligament associated with a unilateral excessive tibial plateau angle (51° in dog 1 and 41° in dog 2) secondary to a growth anomaly. Both dogs underwent a double-cut center of rotation of angulation-based leveling osteotomy combining rotation of the proximal fragment with a cranial closing wedge ostectomy. The procedure allowed leveling of the tibial plateau to a final angle of 11° in one dog and 10° in the other without perioperative complications. Both dogs had excellent functional outcomes ≤ 4 months after the surgery. No postoperative complications were reported during follow-up (12 months and 9 months for dogs 1 and 2, respectively). Results for these dogs suggested that double-cut center of rotation of angulation-based leveling osteotomy can be considered as a viable treatment option for cranial cruciate ligament deficiency associated with excessive tibial plateau angle.

Cranial cruciate ligament rupture in small dogs (

Small breed dogs (<15 kg) affected by cranial cruciate ligament rupture secondary to cranial cruciate ligament disease are usually middle-aged (mean age at presentation: 5.4 to 9.8 years); terrier breeds, miniature and toy poodles are over-represented. Small breed dogs have a different morphology of the proximal tibia compared to medium and large breed dogs with a steep tibial plateau angle (mean tibial plateau angle 28.8° to 36.3°), absent base of the flare of the tibial tuberosity and a caudally bowed fibula. There is a lack of evidence regarding the optimal management of cranial cruciate ligament rupture in small dogs. The treatment options consist of conservative management, extracapsular stabilisation, cranial closing wedge ostectomy, tibial plateau levelling osteotomy and tibial tuberosity advancement. The limited evidence available shows that conservative management is likely to result in prolonged recovery time (average time to recovery approximately 4 months). There is paucity of reports focussing on extracapsular stabilisation in small breed dogs, and questions have been raised regarding the early failure of the extracapsular suture subject to higher loads due to the steep tibial plateau angle of small breed dogs. Cranial closing wedge ostectomy and tibial plateau levelling osteotomy have been reported to have low major complication rates and good subjective outcomes. It is controversial whether tibial tuberosity advancement is a suitable technique in dogs with steep tibial plateau angle, which includes most small breed dogs.

Closing wedge ostectomy and medial distal tibia plate application for treatment of severe bilateral angular limb deformities in the hindlimbs of an 8‐month‐old foal

SummaryThis case report describes the evaluation, surgical approach and outcome of an 8‐month‐old foal with severe angular limb deformities of both metatarsophalangeal joints (MTPJ). Radiography and computed tomography (CT) were used to diagnose a windswept deformity of the hindlimbs with associated bilateral physitis. The orthopaedic surgery was planned and rehearsed using three‐dimensional (3D) bone models. A bilateral closing wedge ostectomy was performed on the distal MtIII, and 3.5 mm LCP® medial distal tibia plates were used bilaterally for osteosynthesis. Even though convalescence was prolonged and complicated by partial unilateral implant failure and osteoarthritis (OA), reduction of the deformities was successful and resulted in a sound foal.

Center of rotation of angulation-based leveling osteotomy combined with a coplanar cranial closing wedge ostectomy to manage cranial cruciate ligament insufficiency in dogs with excessive tibial plateau angle.

To describe outcomes of dogs with excessive tibial plateau angle (eTPA) and cranial cruciate ligament (CrCL) disease treated with center of rotation of angulation-based leveling osteotomy (CBLO) and cranial closing wedge ostectomy (CCWO). Retrospective study. Twenty-one dogs. Medical records of dogs with CrCL disease and eTPA (>34°) treated with CBLO/CCWO were reviewed. Signalment, body weight, intra-articular structure appearance, TPA (preoperatively, postoperatively, and at osteotomy healing), postoperative function, and complications were recorded. Twenty-one dogs (28 stifles) with CrCL disease/eTPA underwent CBLO/CCWO. Twenty stifles had complete CrCL tears and eight tears were partial. Mean age and weight of dogs were 4 years (range, 1-9) and 27 kg (range, 4-65), respectively. Medial menisci were normal in 20 stifles, torn in 5, and degenerative in 3. All lateral menisci were normal. The caudal cruciate ligament was normal in 26 stifles and partially torn in 2. Mean TPA was 43° preoperatively, 10° postoperatively, and 10° at final recheck. Grade 4 healing occurred in all osteotomies by 8 weeks postoperatively. Complications included one pin migration, breakage of two proximal screws (1 case), one late-onset caudolateral band CrCL tear, two late-onset meniscal tears, and one surgical site infection. Eighteen dogs returned to full function, and three dogs achieved acceptable function, at a mean of 27 months. Center of rotation of angulation-based leveling osteotomy/CCWO resulted in grade 4 osteotomy healing by 8 weeks, minimal complications, and acceptable to full return to function. Center of rotation of angulation-based leveling osteotomy/CCWO should be considered to treat canine CrCL disease/eTPA.

Segmental Femoral Ostectomy for the Reconstruction of Femoropatellar Joint in Dogs with Grade IV Medial Patellar Luxation.

The aim of this study was to describe a new surgical method of segmental femoral ostectomy for the reconstruction of the femoropatellar joint (FPJ) in dogs with medial patellar luxation (MPL) grade IV. The medical records of six dogs that underwent segmental femoral ostectomy to reconstruct the FPJ for MPL grade IV were retrospectively reviewed. The data included breed, age, body weight, comorbidities, history of orthopaedic abnormalities, pre- and postoperative radiographic findings, morphological indicators measured on three-dimensional computed tomographic multiplanar reconstruction images, surgical methods and postoperative complications. Eleven hindlimbs with MPL grade IV in six dogs underwent segmental femoral ostectomy to reconstruct the FPJ with the four basic surgical procedures. Six stifle joints with femoral varus deformity were treated by closing wedge ostectomy and segmental ostectomy, while five stifle joints were treated by segmental ostectomy alone. The mean resected femoral length was 11.7 mm. The mean resected femoral length relative to the preoperative femoral length was 14.3%. The stability and congruity of the FPJ was markedly improved, with an increased range of motion in all dogs compared with their preoperative status. Segmental femoral ostectomy was a useful treatment method for MPL grade IV with shortened quadriceps muscle length relative to the femoral length. Reconstruction of the FPJ is important for recovery of limb function.

Three-Dimensional-Printed Patient-Specific Osteotomy Guides, Repositioning Guides and Titanium Plates for Acute Correction of Antebrachial Limb Deformities in Dogs.

The aim of this study was to describe the use of patient-specific three-dimensional (3D)-printed osteotomy guides, repositioning guides and custom-printed titanium plates for acute correction of antebrachial limb deformities in four dogs. Retrospective review of antebrachial limb deformities in small breed chondrodystrophic dogs that were surgically corrected using a closing wedge ostectomy of the radius at a predetermined site using patient-specific osteotomy guides. Reduction was achieved without the need for intraoperative measurements using patient-specific 3D-printed repositioning guides secured and manipulated using temporary Kirschner wire fixation. The ostectomy of the radius was stabilized with a patient-specific 3D-printed titanium plate. All limbs were corrected to within 3.5 degrees (standard deviation [SD]: 1 degree) and 7.5 degrees (SD: 3 degrees) of the pre-planned deformity correction in the frontal and sagittal planes, respectively. No complications were encountered. Owners completed a canine orthopaedic index survey at a median postoperative follow-up time of 19 months. Surgery eliminated the main presenting complaint of buckling over of the manus in all cases. The 3D-printed osteotomy repositioning guides and titanium plates facilitated accurate acute correction of antebrachial deformities in this case series. The methodology described simplifies intraoperative surgical decision-making on limb position with good clinical outcomes seen in a small number of clinical cases.

Closing wedge ostectomy with transfixation pin-cast stabilization for correction of angular limb deformities of the metatarsophalangeal region in four cattle.

4 calves were evaluated because of lameness and an angular limb deformity of the metatarsophalangeal region. 3 calves (ages, 5 days, 10 days, and 1 month) had a congenital varus deformity of the metatarsophalangeal region characterized by medial subluxation of the first phalanx of digits 3 and 4 at the metatarsophalangeal joints. A 6-month-old heifer had a valgus deformity of the metatarsophalangeal region secondary to a malunion of a Salter-Harris type II fracture. The degree of deformity angulation ranged from 16° to 54° for the 4 patients. A closing wedge ostectomy with transfixation pin-cast application was performed on the affected limb of all 4 patients. The ostectomy healed with only minor complications (disuse osteopenia distal to the transfixation pins [n = 4] and cast sores [1]) that were easily resolved with no long-term adverse effects. Duration of follow-up for the 4 patients ranged from 6 to 17 months, and the owners reported satisfactory ambulation with no (n = 2) or only mild (2) residual lameness in the affected limb. Results suggested that a closing wedge ostectomy with transfixation pin-cast stabilization is an alternative for management of angular limb deformities of the metatarsophalangeal region in cattle. Such treatment improved the quality of life for all 4 patients. However, 2 of the 4 patients had congenital deformities confirmed to be heritable. There are ethical concerns associated with treating animals with heritable disorders, and exhibition and breeding of such animals should be avoided.

Computer-Assisted Surgery Using 3D Printed Saw Guides for Acute Correction of Antebrachial Angular Limb Deformities in Dogs.

The aim of this study was to report the use of custom saw guides produced using computed tomographic imaging (CT), computer simulation and three-dimensional (3D) printing to aid surgical correction of antebrachial deformities in six dogs. Antebrachial limb deformities in four small, and two large, breed dogs (seven limbs) were surgically corrected by a radial closing wedge ostectomy and ulnar osteotomy. The location and orientation of the wedge ostectomy were determined using CT data, computer-assisted planning and production of a saw guide in plastic using a 3D printer. At surgery, the guide was clamped to the surface of the radius and used to direct the oscillating saw blade. The resultant ostectomy was closed and stabilized with a bone plate. Five limbs healed without complications. One limb was re-operated due to a poorly resolved rotational component of the deformity. One limb required additional stabilisation with external fixation due to screw loosening. The owners of five dogs completed a Canine Orthopedic Index survey at a follow-up period of 37 to 81 months. The median preoperative score was 3.5 and the median postoperative score was 1, representing an overall positive effect of surgery. Radiographically, 5/7 limbs were corrected in the frontal plane (2/7 were under-corrected). Similarly, 5/7 limbs were corrected in the sagittal plane, and 2/7 were over-corrected in the sagittal place. Computer-aided design and rapid prototyping technologies can be used to create saw guides to simplify one-stage corrective osteotomies of the antebrachium using internal fixation in dogs. Despite the encouraging results, accurate correction of rotational deformity was problematic and this aspect requires further development.

Modified cranial closing wedge ostectomy in 25 dogs.

To describe the planning of a modified cranial closing wedge ostectomy (mCCWO) and determine the accuracy of execution without intraoperative jigs or alignment guides. Retrospective study. Twenty-five client-owned dogs (32 stifles) with cranial cruciate ligament disease. Medical records of dogs treated with mCCWO between July 2014 and December 2016 were reviewed. Preoperative, postoperative, and 8-week-recheck radiographs were reviewed to measure changes in the conformation of the proximal tibia. The accuracy of execution was assessed by comparing planned and actual postoperative tibial plateau angle (TPA) and the lengths of bone contact along osteotomy lines. Radiographic healing and clinical outcome were subjectively evaluated 8 weeks after surgery. Preoperative planning of mCCWO decreased the cranial wedge length by a mean of 23% compared with the traditional CCWO planning. Mean TPA decreased from 40.69 ° (range 28-63) to 6.94 ° (range 2-20) after surgery (P < .001). Mean tibial length decreased by 0.5 mm (±0.16, P = .003), from 138 mm (range 65-267) to 137.5 mm (range 65-265) after mCCWO. The tibial long axis (TLA) shifted by a mean of 3.47 ° (range 0-10). Planned and actual postoperative TPA differed by -0.66 ° (±0.47, P = .034). The proximal and distal apposing osteotomies differed in length by 1.81 mm (±0.35). No bone healing complications or implant failures were diagnosed, and all dogs returned to subjectively satisfactory function by 8 weeks after surgery. The preoperative planning and methods of execution of the mCCWO resulted in differences in target TPA and postoperative TPA, differences in lengths of proximal and distal osteotomies, and tibial shortening that did not appear clinically significant in this study. mCCWO can be planned and accurately executed without consideration of TLA shift or the intraoperative use of alignment guides or jigs.