Articular Comminution Research Articles

Two and Three-Dimensional CT Mapping of Hoffa Fractures.

Hoffa fractures, coronal-plane fractures involving the distal femoral condyles, are unstable, intra-articular fractures. The aim of this study was to define the location and frequency of fracture lines and comminution zones in Hoffa fractures using computed tomography (CT) mapping in both 2-dimensional and 3-dimensional contexts. Seventy-five Hoffa fractures (OTA/AO types 33B3.2 and 33B3.3) were retrospectively reviewed. The directions of fracture lines were characterized in the axial and sagittal CT planes. CT images for all fractures were superimposed on one another and oriented to fit a standard template. Mapping of fracture lines and comminution zones in both the axial and sagittal planes was performed. A 3-dimensional map was created by reducing reconstructed fracture fragments to fit to a model of the distal aspect of the femur. This study included 1 bicondylar and 74 unicondylar (26 medial and 48 lateral) Hoffa fractures. Comminuted fractures accounted for 35.5% of all fractures and 44.9% of lateral fractures. Axial fracture mapping demonstrated that fracture lines were concentrated in the middle-third area of the lateral condyle but were less concentrated and with greater variation in the medial condyle. The mean angle of fracture lines with respect to the posterior condylar axis was 34.4° and 29.0° in the lateral and medial femoral condyles, respectively. Sagittal fracture mapping also demonstrated that fracture lines were concentrated in the middle third of the lateral condyle but were less concentrated in the medial condyle. The mean angle of fracture lines with respect to the posterior cortex of the distal femoral shaft was 23.1° and 19.3° in the lateral and medial condyles, respectively. Three-dimensional mapping demonstrated comminution zones commonly occurring in the weight-bearing zone of the lateral condylar articular surface. Hoffa fractures occurred more frequently in the lateral femoral condyle. In the axial plane, fractures commonly extended from anterolateral to posteromedial in the lateral condyle and from anteromedial to posterolateral in the medial femoral condyle. In the sagittal plane, fractures traversed from anteroinferior to posterosuperior. Articular comminution was more commonly seen in lateral condylar fractures and concentrated in the weight-bearing zone of the articular surface. Research in this area is imperative for optimal preoperative planning, such as for the selection of surgical approach and fixation constructs. Our findings lend insight into fracture morphology, which can assist with fracture classification and the design of biomechanical studies, ultimately aiding in treatment.

Open reduction and internal fixation of comminuted patellar fractures with headless compression screws and wiring technique.

Management of a displaced comminuted patellar fractures is challenging, and various surgical fixation methods have been suggested. However, issues of loss of reduction and breakage of fixatives have not yet been resolved. In the current study, we describe a new technique for exposure and stabilization of comminuted patellar fractures and evaluate the clinical and radiologic outcomes of this new treatment. Thirteen patellar fractures with articular comminution, which were treated by headless compression screws with additional separate vertical wiring were enrolled in this study. Loose articular fragments were fixed with headless compression screws under direct visual reduction of the articular surface, which was facilitated by the superior everting of the patella. Radiographs of the knee were obtained at routine follow-up to assess fracture healing and widening of articular step-off. Clinical outcomes including range of motion, quadriceps circumference, visual analog scale (VAS) related pain score, Lysholm, and Bostman grading scales were measured at the last follow-up. All the fractures healed at a mean of 15 weeks. No patient had loss of reduction, evidence of implant migration, or metallic failure. Articular step-off larger than 2mm was not seen in any of the cases. The average range of motion arc was 134.2° (range, 120°-145°), and the mean Lysholm and Bostman scores were 94.4 (range, 84-100 points) and 28.7 (range, 25-30 points), respectively. Thigh muscle wasting was observed in four patients (33.3%), but no patient had >1.5cm difference in thigh circumference girth between the injured and uninjured lower limbs. The average VAS-related pain score was 0.4. Articular fixations with headless compression screws under direct visual reduction of the articular surface resulted in good clinical outcomes and were considered clinically effective for comminuted patellar fractures.

Outcome of minimally invasive plate osteosynthesis (MIPO) technique in distal tibial fracture

Background: Distal tibial fractures including tibial pilon present a challenge due to subcutaneous location of tibia and precarious blood supply of distal leg. MIPO (Minimal invasive plating osteosynthesis) has evolved as a newer concept to treat distal tibial fractures with minimal articular comminution and minimal soft tissue damage Method: A prospective study for the management of distal tibial fractures by MIPO technique by using LCP (locking compression plate) was done, in 20 patients. Patients were followed and scored according to TEENY and WISS scoring criteria. Result: Among 20 patients, there were 16 males and 4 females with a mean age of 41.4 yrs (range from 20-76yrs). High energy trauma (road traffic accident) predominated causing 11 fractures. Superficial wound infections were seen in 02 cases, surgical wound breakdown with implant exposure in 01 case. 15 patients had excellent, 3 patients had good outcome and 02 patients had fair outcome. Conclusion: We conclude that MIPO is an effective technique for the management of distal tibial fractures.

A Comprehensive Study of Internal Distraction Plating, an Alternative Method for Distal Radius Fractures.

The management of highly comminuted distal radius fractures still remains a major treatment challenge. Articular comminution and compromised bone quality are the culprits. One novel approach is the technique of Internal Distraction Plating which involves "bridging" the fracture with the use of a standard 3.5mm plate applied dorsally in distraction from the radius, proximal to the fracture, to the long finger metacarpal distally, bypassing the comminuted segment. The plate is removed once fracture union has been achieved. The present study was conducted with the aim to evaluate the role of internal dorsal distraction plating as an alternative method in the treatment of fracture distal radius in terms of special indications, technique and outcome. This study was a prospective longitudinal study on 20 patients (mean age 62 years) treated with internal distraction plating for comminuted distal radius fractures with specific indications. Regular follow-ups with standard radiographs and analysis were done upto 24 months. Functional outcome were assessed by DASH Score and the Gartland and Werley demerit score. At final follow-up, all fractures had united and X-rays showed mean palmar tilt of 7°, positive ulnar variance of 0.5mm, radial inclination of 18° and average loss of 2mm of radial height. Mean range of motion values for wrist flexion 46°, extension 50°, pronation 79° and supination 77° At final follow-up, the mean DASH score was 32. 85% patient had excellent to good result as per Gartland and Werley demerit score. This construct has yield satisfactory clinical and radiographic results with these very challenging injuries. The purpose of this study was to report the radiographic and the functional outcomes of treatment with this technique. External fixator and volar plating in communited distal end radius fractures are not always satisfactory in old age with osteoporotic bone because of complications associated with them. The current technique represents an alternative that provides union of the comminuted distal radius fracture with anatomical alignment, optimal range of motion and with minimal clinical disability.

Distal tibia fractures: when is nailing preferred?

Background The treatment of distal tibia fractures remains controversial. Despite the well-known advantages of nailing, its use in distal tibia fractures has been reported to be associated with technical difficulties and high malalignment rates. Many surgeons are still hesitant to use nailing for distal tibia fractures. Objectives The aims of this prospective study were to evaluate the results of using static-reamed intramedullary nailing in the treatment of distal tibia fractures, and to define the situations in which nailing may be preferred. Patients and methods Between January 2008 and December 2011, 30 patients – 21 men and nine women – were treated in King Fahad Hospital at Al-Baha, KSA. Their mean age was 28.6 years. According to the Arbeitsgemeinschaft fur Osteosynthesefragen (AO) classification, 20 cases had type A, eight had type B, and two had type C fractures. Ten fractures were open: four type I, five type II, and one type III-A. The American Orthopedic Foot and Ankle Society ankle–hindfoot scale was used for assessment in this study. Results The mean follow-up time was 26.3 months. Three patients with open fractures got superficial infections. All the fractures united with acceptable alignment in a mean time of 15.74 months with two delayed unions. No difference in alignment was encountered between the immediate postoperative and final radiographs. Limb length discrepancy of 5 mm or less was encountered in one patient. Two (6.66%) patients had less than or equal to 10° reduced range of ankle motion. One (3.33%) patient lost his job, four (13.33%) patients did not return to their preinjury daily activity, and eight (26.66) patients stopped sports-related activities. Implant removal was carried out for three patients with knee pain. The mean American Orthopedic Foot and Ankle Society score was 93 at the end of follow-up. Conclusion Static-reamed nailing is a safe and effective biological stable fixation option in treating distal tibia fractures. Nailing may be preferred in uncontrollable patients, open fractures, osteoporotic bone, pathological fractures, obese patients, and when early weight-bearing is unavoidable. We did not recommend nailing for articular comminution, failure of closed reduction, and types III-B and III-C open fractures.

Does cup-cage reconstruction with oversized cups provide initial stability in THA for osteoporotic acetabular fractures?

The incidence of acetabular fractures in osteoporotic patients is increasing. Immediate total hip arthroplasty (THA) has potential advantages, but achieving acetabular component stability is challenging and, at early followup, reported revision rates for loosening are high. This study measured acetabular component stability and the initial surface contact achieved between the acetabular component and unfractured region of the pelvis after THA using an oversized acetabular component and cup-cage reconstruction. Between November 2011 and November 2013, we treated 40 acute acetabular fractures in patients older than 70 years of age. Of these, 12 (30%) underwent immediate THA using an oversized acetabular component with screws inserted only into the ilium and a cup-cage construct. Postoperatively all patients were mobilized without weightbearing restrictions. Indications for immediate THA after acetabular fractures were displaced articular comminution deemed unreducible. Eleven of the 12 were prospectively studied to evaluate the initial stability of the reconstructions using radiostereometric analysis. One of the patients died of a pulmonary embolism after surgery, and the remaining 10 (median age, 81 years; range, 72-86 years) were studied. Of these, five were analyzed at 1 year and five were analyzed at 2 years. Acetabular component migration was defined as acceptable if less than the limits for primary THA that predict later loosening (1.76 mm of proximal migration and 2.53° of sagittal rotation). The contact surface between the acetabular component and ilium in direct continuity with the sacroiliac joint, and the ischium and pubis in direct continuity with the symphysis pubis, was measured on postoperative CT scans. At 1 year the median proximal migration was 0.83 mm (range, 0.09-5.13 mm) and sagittal rotation was 1.3° (range, 0.1°-7.4°). Three of the 10 components had migration above the suggested limits for primary THA at 1 year postoperatively. The contact surface achieved at surgery between the acetabular component and pelvis ranged from 11 to 17 cm(2) (15%-27% of each component). The majority of acetabular components in this cohort were stable despite the small contact surface achieved between the component and pelvic bone. Three of 10 migrated in excess of the limits that predict later loosening in primary THA but it remains to be seen whether these limits apply to this selected group of frail osteoporotic patients. We continue to use this technique routinely to treat patients with the same indications, but since the analysis of these data we have added screw fixation of the acetabular component to the ischial tuberosity and the superior pubic ramus. Level IV, therapeutic study.

Coronal shear fractures of distal humerus: Diagnostic and treatment protocols.

Coronal shear fractures of distal humerus involving the capitellum and the trochlea are rare injuries with articular complexity, and are technically challenging for management. With better understanding of the anatomy and imaging advancements, the complex nature of these fractures is well appreciated now. These fractures involve metaphysealcomminution of lateral column and associated intraarticular injuries are common. Previously, closed reduction and excision were the accepted treatment but now preference is for open reduction and internal fixation with an aim to provide stable and congruent joint with early range of motion of joint. Various approaches including extensile lateral, anterolateral and posterior approaches have been described depending on the fracture pattern and complexity. Good to excellent outcome have been reported with internal fixations and poor results are noted in articular comminution with associated articular injuries. Various implants including headleass compression screws, minifragment screws, bioabsorbable implants and column plating are advocated for reconstruction of these complex fractures. Inspite of articular fragments being free of soft tissue attachments the rate of osteonecrosis and osteoarthritis is reported very less after internal fixation. This article summarizes the diagnostic and treatment strategies for these rare fractures and recommendations for management.

Study of outcomes of dual plate osteosynthesis in Schatzker type 5 and 6 fractures of proximal tibia

Background: The operative treatment of complicated bicondylar fractures of the tibial plateau remains a challenge to even the most experienced surgeons. Such injuries are usually the result of high-energy trauma, and the management of such fractures is complicated by metaphyseal and articular comminution and the frequent occurrence of associated soft tissue injuries. Aims: The aim of this retrospective study was to evaluate the clinical and radiological outcomes of dual plating for treating Schatzker types 5 and 6 bicondylar tibial plateau fractures. Methods: 24 patients with bicondylar tibial plateau fractures and operatively treated in our orthopedic department with dual-plating technique between January 2006 and December 2012 were retrospectively analyzed. Inclusion criteria for this study were (1) acute and unilateral fractures and (2) displaced bicondylar tibial plateau fractures (Orthopaedic Trauma Association types C1, C2, and C3).Knee score was used for evaluation of outcome Results: At 12 months postoperatively, the knee score was 88.5 and 84.4in the double buttress plate and combination plate groups, respectively, and the difference was not significant. Out of 24 patients 19 achieved excellent knee score (>90), 4 achieved good (80-90), 1 achieved fair (70-80) and no patient had poor (<70) knee score. Mean range of knee flexion was 115 degrees for dual buttress group and 117.5 degree for combination group. Conclusion: Dual plating in Schatzker type 5 and 6 fractures results in good outcome with low complication rates.

Outcome of Minimaly Invasive Plate Osteosynthesis (MIPO) Technique with Locking Compression Plate in Distal Tibial Fracture Management

Background: Distal tibial fractures including tibial pilon present a challenge as to their best method of management due to subcutaneous location of larger portion of tibia, paucity of soft tissue coverage and precarious blood supply of distal leg. MIPO (Minimal invasive plating osteosynthesis) has evolved as a newer concept to treat distal tibial fractures with minimal articular comminution and minimal soft tissue damage. It works on Biological fixation principle which assists physiological process of bone healing wisely with minimal operative intervention. Method: A prospective study for the management of distal tibial fractures by MIPO technique by using pre-contoured metaphyseal LCP (locking compression plate) was done, in 20 patients, between January 2012 and October 2013. Fractures were classified as per AO system and patients were followed and scored according to TEENY and WISS clinical scoring criteria. Result: Among 20 patients operated, there were 15 males and 5 females with a mean age of 38.95yrs (range from20-67yrs). 17 patients sustained extra-articular fractures (type A), 02 partial-articular fractures (type-B) and 01 total-articular fracture (type-C). High energy trauma (road traffic accident) predominated causing 13 fractures. Average trauma surgery interval was 12 days (02-22days). Patients were followed minimum for 6 months (range 06-18 months). Superficial wound infections were seen in 02 cases, surgical wound breakdown with implant exposure in 01 case and prominent hardware in 01 case. 17 patients (85%) had excellent/good outcome and 03 cases with complications had fair (02 cases) to poor (01 case) outcome. Conclusion: MIPO is an effective and safe technique for the management of distal tibial fractures without intra-articular comminution and minimum soft tissue damage. It preserves bone biology by maintaining balance between devascularisation and mechanical perfection. Further studies with longer follow-up and large sample size are warranted.

A Scaphoid Osteochondral Autograft for Reconstruction of the Lunate Fossa of the Distal Part of the Radius After a Complex Open Fracture: A Case Report.

Complex fractures of the distal part of the radius in high-energy injuries or in elderly osteopenic patients often have extensive articular comminution. Often, these small fragments are not amenable to primary fixation. In high-energy open fractures, there may be substantial bone loss or missing osteochondral fragments. Moreover, concomitant carpal fractures are often present, as well as associated radiocarpal and carpal dislocations that offer additional challenges. Primary total wrist arthrodesis has been suggested for treatment of these difficult injuries1. Motion-preserving salvage procedures include total wrist arthroplasty, limited wrist fusion, and proximal row carpectomy (PRC). Total wrist arthroplasty is contraindicated in younger, more active patients because current implants require a low-demand lifestyle, and complication rates following surgery remain high2. Limited wrist fusion and PRC require an intact lunate fossa and thus may not be options in cases with substantial loss of articular surface. Autogenous osteochondral graft reconstruction of the articular surface of the distal part of the radius has been described in some small case series3-7. PRC involves resection of the scaphoid, lunate, and triquetrum, allowing the capitate to articulate with the lunate facet of the distal part of the radius. The scaphoid is therefore an ideal potential osteochondral donor graft for salvage of the lunate fossa when PRC is to be performed because it does not require a separate graft harvest procedure and does not cause additional donor-site morbidity. We report a case of a complex open radiocarpal fracture-dislocation with bone loss, demonstrating salvage of the lunate facet of the distal part of the radius with a scaphoid osteochondral autograft. The patient was informed that data concerning the case would be submitted for publication, and he provided consent. A twenty-five-year-old man was involved in a rollover motor vehicle collision and was transferred to …

Role of minimally invasive percutaneous plate osteosynthesis in the treatment of distal diametaphyseal tibial fractures

The fractures of the distal tibia represent 7-10% o f all tibial fractures and they usually encompass a spectrum of skeletal injury ranging from fractures caused by low-energy rotational forces to fractures caused by high-energ y axial compression forces arising from motor vehicle accidents or fall s from a height. Rotational variants typically have a more favorable prognosis, whereas high-energy fractures frequently are associated with open wounds or severe, closed, soft-tissue trauma. The fracture may have significant metaphyseal or ar ticular comminution or diaphyseal extension. Better prognosis are given in case of low energy traumas. The study eval uates the results of the surgical treatment of dist al tibia fractures, using minimally invasive plate osteosynthesis (MIPPO) technique. We treated in our unit 18 patients with dis tal tibia fractures with the MIPPO technique. The fractures, intra-arti cular or extra-articular, were classified according to the AO classification. The cases studied did not involve c ompound fractures or local dermatological lesions a nd we excluded the C3 fractures, for which traditional osteosynthesis is preferable. On the whole the outcomes were posit ive, thanks to a correct clinical indication. In conclusion we think that two are the elements that direct the choice r egarding the type of approach and the type of device for the synthesis. The first is the condition of the skin, as far as i ts integrity is concerned, and the second is the articular condition, as far a s the comminution and the number of fragments are concerned. Therefore we need to choose a synthesis that can guarantee a good outcome and can avoid dreadful complications and MIPPO is a valid technique when used correctly and by experts.

Retrograde tibiotalocalcaneal nails

No consensus exists on the optimal treatment method of type III open pilon fractures. Despite staged management, the outcome remains unsatisfactory. Since 2008, we have been treating open grade III tibial pilon fractures that cannot be reconstructed with a retrograde calcaneotalotibial fusion nail after 2 weeks of ankle bridging external fixation. Patients with severe soft-tissue injury and comorbidities such that the infection risk after a large skin incision is deemed unacceptable or the degree of articular comminution does not allow reconstruction are candidates for the above procedure. These patients undergo staged treatment with external fixation initially and conversion to retrograde tibiotalocalcaneal nailing as a second procedure. We have noted no infections, but removal of a prominent calcaneal screw was required in one patient. A retrograde tibiotalocalcaneal nail allows the soft-tissue envelope to be left intact, thus decreasing the incidence of deep-seated infection. The method decreases pain, reduces the number of operative procedures needed, and aids an early return to activity, making it an option in the treatment of open type III tibial pilon fractures.

Fractures in Brief: Olecranon Fractures

Olecranon fractures are relatively common injuries, accounting for approximately 10% of upper extremity fractures in adults [26]. These fractures may result from a direct blow to the proximal ulna, or indirectly, via the forceful contraction of the triceps against resistance (typically, during a fall onto an outstretched hand). Less commonly, the olecranon may fracture when the elbow is hyperextended, as the bone is impacted against the olecranon fossa of the distal humerus. For unstable injuries, operative fixation typically is required. Even after recovery, loss of ROM is not uncommon. This article provides an overview of olecranon fractures in adults; therefore, discussion of olecranon fractures in skeletally immature patients is beyond the scope of this article.

Paratricipital-Triceps Splitting “Two-Window” Approach for Distal Humerus Fractures

Commonly, distal transcondylar and intra-articular distal humerus fractures are treated through a transolecranon approach. Other options for exposure, open reduction, and internal fixation exist to prevent the reported complications of olecranon osteotomy. The technique of triceps sparing access, as it has been reported before by others, allow adequate exposure in most of distal humerus fractures except for multifragmentary, mainly intra-articular types. We demonstrate the technique of the "two-window" approach, which combines a paratricipital posteromedial access with splitting the triceps lateral to the triceps tendon. Through a posteromedial incision, all surfaces of the distal humerus were accessed without muscle detachment from the olecranon. This approach does not compromise the ligamentous joint stability. In addition, the stabilizing effect of the anconeus muscle is not impaired because continuity with the lateral portion of the triceps is preserved, and denervation is avoided. It is extensile and provides adequate exposure of articular fracture comminution with the added advantage of the intact olecranon as a template for reduction. However, because the triceps is still in continuity it permits conversion to a transolecranon approach as necessary. The two-window approach is our preferred approach for all distal humerus fractures inclusively C3 fractures according to the ASIF/AO classification, except for complex volar shear fractures.

Association Between Decreased Bone Mineral Density and Severity of Distal Radial Fractures

The role of osteoporosis and osteopenia in the etiology of fractures of the distal part of the radius is well established, but any link between osteoporosis and the severity of the distal radial fracture has not been extensively investigated. The aim of this study was to investigate the association between the degree of osteoporosis and the severity of distal radial fractures. All patients over fifty-five years of age with a low-energy distal radial fracture were offered dual x-ray absorptiometry scanning of the hip. Data on the 137 consecutive patients were collected prospectively. Plain radiographs of the fractured distal part of the radius were assessed for angulation, metaphyseal and articular comminution, carpal malalignment, ulnar variance, AO/OTA group and subgroup classification, early and late displacement, and malunion. Fracture severity was quantified with use of previously published algorithms for calculating the probability of early and late displacement, late carpal malalignment, and malunion. These severity scores were correlated with the dual x-ray absorptiometry T-scores, which represent the number of standard deviations by which the measured bone density differs from the mean value in healthy controls. There was a significant linear correlation between increasingly negative T-scores and increasing likelihood of early instability, late carpal malalignment, and malunion. Patients with osteoporosis (a T-score of less than -2.5) had a 43% probability of having early instability, a 39% probability of having late carpal malalignment, and a 66% probability of having malunion. Patients with osteopenia (a T-score of more than -2.5 but less than -1) had a 35% probability of having early instability, a 31% probability of having late carpal malalignment, and a 56% probability of having malunion. This compared with a 28% probability of early instability, a 25% probability of late carpal malalignment, and a 48% probability of malunion in patients with normal bone mineral density (a T-score of more than -1). There is a definite correlation between bone mineral density and the severity of distal radial fractures.

Frequency and Fracture Morphology of the Posteromedial Fragment in Bicondylar Tibial Plateau Fracture Patterns

Bicondylar tibial plateau fracture management remains therapeutically challenging, partly because of multiplanar articular comminution. This study was performed to evaluate the frequency and morphologic characteristics of the posteromedial fragment in this injury pattern. Retrospective chart and radiographic review. Urban Level 1 university trauma center. Fifty-seven patients sustaining 57 Orthopedic Trauma Association (OTA) C-Type bicondylar tibial plateau fractures formed the study group. Between May 2000 and March 2003, 170 OTA C-Type bicondylar tibial plateau fractures were identified using an orthopaedic database. One hundred and forty-six fractures had computed tomographic (CT) scans performed prior to definitive fixation and were reviewed using the Picture Archiving and Communication System (PACS). Sixty-six (45.2%) injuries had fractures that involved the medial articular surface. Nine with suboptimal CTs were excluded, leaving 57 injuries for review. Forty-two patients demonstrated coronal plane posteromedial fragments. Morphologic evaluation of the posteromedial fragment included articular surface area, maximum posterior cortical height (PCH), and sagittal fracture angle (SFA). Forty-two of 57 injuries (74%) demonstrated a posteromedial fragment that comprised a mean of 58% of the articular surface of the medial tibial plateau (range, 19%-98%) and a mean of 23% of the entire tibial plateau articular surface (range, 8%-47%). Mean posteromedial fragment height was 42 mm (range, 16-59 mm), and mean sagittal fracture angle was 81 degrees (range, 33 degrees to 112 degrees). Six patients demonstrated fracture patterns not accurately identified by the AO/OTA (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association) fracture classification system. A posteromedial fragment was observed in nearly one third of the bicondylar plateau fractures evaluated. The morphologic features of this fragment may have clinical implications when using currently available laterally applied fixed-angle screw/plate implants to stabilize these injuries. Alternate or supplementary fixation methods may be required when managing this injury pattern.

Comparison of Radiography and Computed Tomography to Evaluate Metacarpo/Metatarsophalangeal Joint Pathology of Paired Limbs of Thoroughbred Racehorses with Severe Condylar Fracture

To compare the orthogonal radiographic (OR) and computed tomographic (CT) appearance of paired Thoroughbred racehorse limbs with severe condylar fracture. In vitro study. Cadaveric paired limbs with severe condylar fracture (n=11 horses). Four standard radiographic and multiple transverse CT images were obtained of the fractured and contralateral limbs centering on the metacarpo/metatarsophalangeal (fetlock) joints. Radiographs and CT images were graded by 4 raters, and interobserver agreement was calculated. Imaging evaluations were supplemented by fetlock joint dissection. A consensus description of actual injury and the detection accuracy of OR and CT for that injury was determined. Results- Rater agreement for OR and CT for most pathologic features was good or excellent. OR was similar to CT for the detection of condylar and diaphyseal third metacarpal and metatarsal (MC/MT3) fractures, diaphyseal fractures of the first phalanx (P1), and fracture location on the condyle. CT was superior to OR for detection of MC/MT3 proximal fissures and articular comminution, condylar small cracks and lucencies, and proximal sesamoid fractures. OR was superior to CT for detection of proximal P1 dorsal fractures. Both OR and CT were poor at detecting palmar/planter proximal P1 fractures and coalescing cracks in the subchondral bone of MC/MT3. CT is better than OR for detection of pathology in limbs with condylar fractures, but does not detect every pathologic feature. CT provides superior information of pathology in Thoroughbred racehorses with condylar fractures.

Two and Three-Dimensional Computed Tomography for the Classification and Management of Distal Humeral Fractures

Complex fractures of the distal part of the humerus can be difficult to characterize on plain radiographs and two-dimensional computed tomography scans. We tested the hypothesis that three-dimensional reconstructions of computed tomography scans improve the reliability and accuracy of fracture characterization, classification, and treatment decisions. Five independent observers evaluated thirty consecutive intra-articular fractures of the distal part of the humerus for the presence of five fracture characteristics: a fracture line in the coronal plane; articular comminution; metaphyseal comminution; the presence of separate, entirely articular fragments; and impaction of the articular surface. Fractures were also classified according to the AO/ASIF Comprehensive Classification of Fractures and the classification system of Mehne and Matta. Two rounds of evaluation were performed and then compared. Initially, a combination of plain radiographs and two-dimensional computed tomography scans (2D) were evaluated, and then, two weeks later, a combination of radiographs, two-dimensional computed tomography scans, and three-dimensional reconstructions of computed tomography scans (3D) were assessed. Three-dimensional computed tomography improved both the intraobserver and the interobserver reliability of the AO classification system and the Mehne and Matta classification system. Three-dimensional computed tomography reconstructions also improved the intraobserver agreement for all fracture characteristics, from moderate (average kappa [kappa2D] = 0.554) to substantial agreement (kappa3D = 0.793). The addition of three-dimensional images had limited influence on the interobserver reliability and diagnostic characteristics (sensitivity, specificity, and accuracy) for the recognition of specific fracture characteristics. Three-dimensional computed tomography images improved intraobserver agreement (kappa2D = 0.62 compared with kappa3D = 0.75) but not interobserver agreement (kappa2D = 0.24 compared with kappa3D = 0.28) for treatment decisions. Three-dimensional reconstructions improve the reliability, but not the accuracy, of fracture classification and characterization. The influence of three-dimensional computed tomography was much more notable for intraobserver comparisons than for interobserver comparisons, suggesting that different observers see different things in the scans-most likely a reflection of the training, knowledge, and experience of the observer with regard to these relatively uncommon and complex injuries.

The Influence of Three-Dimensional Computed Tomography Reconstructions on the Characterization and Treatment of Distal Radial Fractures

Computed tomography identifies important characteristics of distal radial fractures better than plain radiographs do. Our hypothesis was that three-dimensional computed tomography images would further increase the reliability and accuracy of radiographic characterization of distal radial fractures. Four independent observers evaluated radiographic images of thirty intra-articular fractures of the distal part of the radius for the presence of a fracture line in the coronal plane, impacted central articular fragments, the presence of comminution (defined as more than three articular fragments), and the number of fracture fragments. A treatment was selected on the basis of the interpretation of the radiographic studies. Three rounds of evaluation were compared: (1) radiographs and two-dimensional computed tomography, (2) radiographs and three-dimensional computed tomography two weeks later, and (3) all three types of images two weeks after that. This cycle was then repeated to assess intraobserver reliability. Three-dimensional computed tomography improved the intraobserver agreement, but not the interobserver agreement, regarding the presence of coronal plane fracture lines and central articular fragment depression. Three-dimensional computed tomography improved both the intraobserver and the interobserver agreement regarding the presence of articular comminution. Interobserver agreement increased when three-dimensional computed tomography was used to determine the exact number of articular fracture fragments. The sensitivity and accuracy of identifying specific fracture characteristics (as compared with intraoperative findings) improved when three-dimensional imaging was used in conjunction with two-dimensional imaging as compared with two-dimensional imaging alone. The addition of three-dimensional computed tomography to two-dimensional computed tomography influenced treatment recommendations, resulting in a significantly greater number of decisions for an open approach (p < 0.05) and combined dorsal and volar exposure (p < 0.001). Three-dimensional computed tomography improves both the reliability and the accuracy of radiographic characterization of articular fractures of the distal part of the radius and influences treatment decisions. Future studies will be required to determine the impact of these decisions on patient outcome.

THE INFLUENCE OF THREE-DIMENSIONAL COMPUTED TOMOGRAPHY RECONSTRUCTIONS ON THE CHARACTERIZATION AND TREATMENT OF DISTAL RADIAL FRACTURES

Background: Computed tomography identifies important characteristics of distal radial fractures better than plain radiographs do. Our hypothesis was that three-dimensional computed tomography images would further increase the reliability and accuracy of radiographic characterization of distal radial fractures. Methods: Four independent observers evaluated radiographic images of thirty intra-articular fractures of the distal part of the radius for the presence of a fracture line in the coronal plane, impacted central articular fragments, the presence of comminution (defined as more than three articular fragments), and the number of fracture fragments. A treatment was selected on the basis of the interpretation of the radiographic studies. Three rounds of evaluation were compared: (1) radiographs and two-dimensional computed tomography, (2) radiographs and three-dimensional computed tomography two weeks later, and (3) all three types of images two weeks after that. This cycle was then repeated to assess intraobserver reliability. Results: Three-dimensional computed tomography improved the intraobserver agreement, but not the interobserver agreement, regarding the presence of coronal plane fracture lines and central articular fragment depression. Three-dimensional computed tomography improved both the intraobserver and the interobserver agreement regarding the presence of articular comminution. Interobserver agreement increased when three-dimensional computed tomography was used to determine the exact number of articular fracture fragments. The sensitivity and accuracy of identifying specific fracture characteristics (as compared with intraoperative findings) improved when three-dimensional imaging was used in conjunction with two-dimensional imaging as compared with two-dimensional imaging alone. The addition of three-dimensional computed tomography to two-dimensional computed tomography influenced treatment recommendations, resulting in a significantly greater number of decisions for an open approach (p < 0.05) and combined dorsal and volar exposure (p < 0.001). Conclusions: Three-dimensional computed tomography improves both the reliability and the accuracy of radiographic characterization of articular fractures of the distal part of the radius and influences treatment decisions. Future studies will be required to determine the impact of these decisions on patient outcome.