TMJ arthrosis: does the occlusal relationship really interfere? A comparison between cone beam computed tomography and dried skulls.

The aim of this study was to investigate the association between condylar bone morphological characteristics with occlusal conditions. Besides the study will compare the tomography images with the real condition in 122 temporomandibular joints from 61 skulls. The occlusal conditions were evaluated by number of teeth missing, measurement of overjet and overbite, in millimeters, and presence or absence of crossbite, openbite and dental rotation. The condylar bone morphological conditions were classified in five types (normal, presence of erosion, presence of osteophytes, flattening and/or deformation). This classification was used in real skulls and in Cone Beam Computed tomography (CBCT) images. The data were submitted to statistical analysis with a level of significance of 0.05. Occlusal variables have no association to morphologic data (p > 0.05). Normal condylar bone was seen in 62 CBCT versus 53 in real skulls while morphological alterations were seen in 60 CBCT versus 67-real condyles. The clinical and tomographic measurements were compared, demonstrating an important difference in the classification demonstrating poor association between detection methods (k - 0.3, p < 0.001). The occlusal conditions appear to have no correlation with the morphological condyle conditions. The CBCT is a reliable diagnostic method, although it may present divergences of findings when compared with clinical raw examination to morphologic condylar conditions.

Clinical and radiographic results of cementless reverse total shoulder arthroplasty: a comparative study with 2 to 5 years of follow-up.

BACKGROUND: Most studies of reverse total shoulder arthroplasty (RTSA) involve cemented humeral stems. To our knowledge, this is the first study to compare the results of cementless RTSA, using a porous-coated stem designed for uncemented fixation, with cemented RTSA. METHODS: A prospective database of patients undergoing RTSA was retrospectively reviewed for patients with a diagnosis of cuff tear arthropathy or severe rotator cuff deficiency with minimum 2-year follow-up. Of these, 37 patients had cemented RTSA and 64 patients had cementless RTSA. Outcome measures included Constant-Murley scores, American Shoulder and Elbow Surgeons scores, visual analog pain scale scores, range of motion, patient satisfaction, and radiographic evidence of complication. RESULTS: Compared with preoperative values, both cohorts demonstrated significant improvements (P < .01) in all functional scores, active forward elevation, and active internal rotation. There was no significant difference (P > .05) in comparing the changes in these values after surgery between the cemented and cementless cohorts. On radiographic evaluation, there was no evidence of loosening or humeral components "at risk" of loosening in either group. There was no significant difference (P = 1.0) in the incidence of humeral component radiolucent lines between the cemented and uncemented cohorts. There was no significant difference (P = .30) in the incidence of scapular notching between the cemented (n = 8) and uncemented (n = 10) cohorts. CONCLUSION: Cementless fixation of a porous-coated RTSA humeral stem provides clinical and radiographic outcomes equivalent to those of cemented stems at minimum 2-year follow-up. With advantages such as simplified operative technique, no cement-related complications, greater ease of revision, and long-lasting biologic fixation, uncemented fixation may provide several benefits over cemented fixation.

Nonstandard glenoid components for bone deficiencies in shoulder arthroplasty.

BACKGROUND: Glenoid bone deficiencies may be addressed by specialized components. The purpose of this study is to evaluate the clinical and radiographic outcomes of 3 different types of nonstandard glenoid components. MATERIALS AND METHODS: Thirty-eight patients with a mean age of 65 years (range, 34-84 years) underwent a primary or revision anatomic shoulder arthroplasty with one of 3 nonstandard glenoid components: a polyethylene component with an angled keel for posterior glenoid wear without posterior subluxation; a polyethylene component with 2 mm of extra thickness for central glenoid erosion; or a posteriorly augmented metal-backed glenoid component for posterior glenoid wear and posterior subluxation. Average clinical follow-up was 7.3 years (range, 2-19 years) or until revision surgery. RESULTS: At the most recent follow-up, 24 patients had no, mild, or occasionally moderate pain. Mean elevation improved from 91° to 126°, and mean external rotation improved from 24° to 53°. Thirteen patients had moderate or severe subluxation preoperatively, and 11 had subluxation at follow-up. On radiographic evaluation, 3 glenoid components had loosened and 3 were at risk for loosening at an average 5.5 years of follow-up. Seven patients had revision surgery: 4 for instability, 1 for osteolysis, 1 for component loosening with osteolysis, and 1 for a periprosthetic fracture. Three additional patients had removal of glenoid components, 2 for infection and 1 for loosening. Ten-year survival rate free of revision or removal of the angled keel component was 73% (95% CI: 75.3-70.7); of the extra thick (+2 mm) component, 69% (95% CI: 65-73); and of the posteriorly augmented metal-backed glenoid component, 31% (95% CI: 35.6-26.4). CONCLUSIONS: The effectiveness of nonstandard glenoid components in addressing glenoid bone deficiencies is compromised by an increased rate of component loosening and by only partial success in eliminating subluxation.

Massive bone defect compromises postoperative cup survivorship of acetabular revision hip arthroplasty with impaction bone grafting.

We evaluated 66 acetabular revision arthroplasties using cemented cup with impaction bone grafting (IBG) to detect the extent that bone defect affects the outcome. We defined the maximum acetabular defect distance (MADD), which indicates the greatest depth of the grafted layer. Cup survival analysis with aseptic loosening as the endpoint revealed that the "MADD≤20mm" group showed higher survivorship than the "MADD>20mm" group (95% vs. 74%, P=0.034), and that the simple-wall-defect group (none or one mesh used) showed higher survivorship than the complex-wall-defect group (two meshes used) (96% vs. 73%, P=0.044). A favorable indication for acetabular IBG reconstruction is cases in which those cups can be placed at≤20mm MADD with a simple wall defect.

Changes of periprosthetic bone density after a cementless short hip stem: a clinical and radiological analysis.

PURPOSE: The purpose of this study was to examine the concept of proximal load initiation of a total short-stemmed hip arthroplasty (Metha BBraun, Aesculap, Tuttlingen, Germany) on the basis of bone variations by means of osteodensitometric dual energy X-ray absorptiometry and radiologic measurements. METHODS: After power analysis 40 patients were included in this study. DXA examination, radiological and clinical follow-up was performed pre-operatively and postoperatively. Socio-demographic relevancies of bone progression and radiological changes were raised epidemiologically and clinically. RESULTS: Improvement of the Harris hip score from 54.7 points preoperative to 96.7 points postoperative was detected (p < 0.01). Loss of summarized overall net average bone mass density (netavg BMD) could only be manifested after six months compared to the netavg BMD of the postoperative measurement (p < 0.01). After six and 12 months BMD atrophy was shown mainly in regions of interest (ROI) 1, 4 and 7. Positive correlations between changes of BMD and age, male sex and BMI were detectable. No stem had to be revised. CONCLUSIONS: The Metha implant shows excellent osseointegration at the coated area of the stem without factors of aseptic loosening in the short term. This study shows that parameters like age, sex and BMI influence BMD progression and stress shielding. Metha implant shows excellent results especially in young patients with good bone stock.

Arthropathy, osteolysis, keloids, relapsing conjunctival pannus and gingival overgrowth: a variant of polyfibromatosis?

Polyfibromatosis is a rare fibrosing condition characterized by fibromatosis in different body areas and by keloid formation, and which can be associated with arthropathy and osteolysis. Familial occurrence has been described, but the cause remains unknown. Here, we describe a patient with characteristics of polyfibromatosis with arthropathy who had in addition severe conjunctival fibrosis, distinctive face, gingival overgrowth, and pigmented keloids. We discuss the resemblances and differences with polyfibromatosis and descriptions of other, similar patients. We conclude that at present it remains uncertain whether the patient has a variant of polyfibromatosis or a separate entity.

Early migration of the cemented tibial component of unicompartmental knee arthroplasty: a radiostereometry study.

PURPOSE: Unicompartmental knee arthroplasty has good clinical results but high revision rates. A unicompartmental knee arthroplasty design features an all-polyethylene and conforming tibial component, and we hypothesized that this may put at risk its fixation. Implant-to-bone micromotion was measured together with relevant clinical outcomes. METHODS: The migration of the tibial component in twenty patients was measured at 3, 6, 12 and 24 months, using standard radiostereometry, along with the relevant clinical outcomes using the IKS scoring system. RESULTS: The eighteen arthroplasties at 24 months were found successful, with very good functional (mean 87.7; SD 15.4) and knee scores (mean 94.8; SD 10.1). The means and the standard deviations of the maximum total point motion (MTPM) for the four follow-ups were, respectively, as small as 0.4 ± 0.1 mm, 0.6 ± 0.2 mm, 0.6 ± 0.3 mm and 0.7 ± 0.3 mm, an average over all patients but one. In this knee, these were 1.6, 2.1, 2.4 and 2.2 mm, therefore not at high risk of aseptic loosening according to the literature. Only one knee was found at this risk, having the MTPM from 12 to 24 months of 0.5 mm, and the component moving and sinking medially, and rising laterally. CONCLUSION: At 2-year follow-up, a successful implant-to-bone fixation can be achieved in conforming all-polyethylene cemented tibial component together with excellent clinical outcomes.

Radiographic results of fully uncemented trabecular metal reverse shoulder system at 1 and 2 years' follow-up.

BACKGROUND: The purpose of this study was to assess the short-term radiographic outcome of a fully uncemented reverse total shoulder arthroplasty (RTSA) system. MATERIALS AND METHODS: We reviewed the radiographs of 98 consecutive patients undergoing uncemented RTSA. All patients had a standardized series of radiographs taken at 2 weeks, 1 year, and 2 years postoperatively. Humeral stems were evaluated for radiolucent lines by zone and component subsidence. Evaluation for scapular notching and radiolucency surrounding the baseplate implant within the glenoid vault was also performed. RESULTS: At 1 year, 93.9% of humeral stems had no lucent lines and 6.1% had less than 2 mm of lucency. Of the scapulae, 76.6% showed no evidence of notching, 21.4% had type 1 scapular notching, and 2.0% had type 2 notching at 1 year. At 2 years, 89.5% of humeral stem components had no lucent lines and 10.5% had less than 2 mm of lucency. Fifty-seven percent of scapulae had no notching, 34.2% had type 1 notching, 5.3% had type 2 notching, and 2.6% had type 3 notching. No stems had lucency in more than 1 zone or lucency ≥ 2 mm; 9.2% had subsidence of 2 mm or less. No glenoid components had any lucency around the baseplate or screws. CONCLUSIONS: Cementless trabecular metal porous-coated implants for RTSA are associated with secure glenoid fixation and minimal radiographic evidence of humeral stem loosening or subsidence at short-term follow-up. The rates of scapular notching found in our study are comparable to previous studies and did not affect implant stability.

Surgeon error in performing intraoperative estimation of stem anteversion in cementless total hip arthroplasty.

To examine the accuracy of intraoperative estimation of stem anteversion in total hip arthroplasty (THA), we compared the intraoperatively estimated stem anteversion (estimated prosthetic anteversion) to stem anteversion measured by postoperative computed tomography (true anteversion) in 73 hips in 73 patients. Estimated prosthetic anteversion was significantly greater than true anteversion by 5.8°, and the mean absolute value of surgeon error was 7.3° ranging from 11° underestimation to 25° overestimation. Surgeons tended to overestimate when the true anteversion was smaller. A multivariate analysis showed that advanced knee osteoarthritis significantly increased surgeon error. These results indicated that estimated prosthetic anteversion was generally larger than true anteversion and that the grade of knee osteoarthritis affected the degree of surgeon error.

Open ankle arthrodeses via an anterior approach.

BACKGROUND: In open ankle arthrodesis, debate remains as to which surgical approach and fixation devices should be used. The purpose of this study was to identify union, complication, and patient satisfaction rates of ankle fusions performed at our institution, using the plane between extensor hallucis longus and tibialis anterior with medial tibiotalar screw internal fixation. MATERIALS AND METHODS: A retrospective review was performed of all isolated primary fusions between 2005 and 2009. Eighty-two ankles were identified in 73 patients. All patient records were reviewed, and 57 patients (65 ankles) attended for clinical evaluation and scoring. Age range at surgery was 18 to 75 years (mean, 56.1 years); 8 patients were smokers. Diagnoses were trauma in 52 patients (63%), osteoarthritis in 17, rheumatoid arthritis in 7, Charcot-Marie-Tooth disease in 3, congenital talipes equinovarus in 2, and talar avascular necrosis in 1. Follow-up range was 7 months to 8.3 years (mean, 4 years). RESULTS: Time to union ranged from 8 to 39 weeks (mean, 13.3) with a union rate of 100%. The AOFAS range was 12 to 93 (mean, 70). Eighty percent were "very satisfied" or "satisfied." Major complication rate was 14.6%: 7 malalignments; 3 wound problems; 2 complex regional pain syndrome; and 2 delayed unions, both smokers. CONCLUSIONS: An excellent union rate, high patient satisfaction, and low complication rate were achieved with this technique. Varus malalignment and persistent pain resulted in dissatisfaction. Many patients remained highly active, and bilaterally fused patients functioned as well as unilateral ones. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Cementless femoral reconstruction in patients with proximal femoral deformity.

Distorted proximal femoral anatomy can pose a great technical challenge during total hip arthroplasty. Fifty-eight total hip arthroplasty were performed in 51 patients with proximal femoral deformity from 1998 to 2006. All hips except 2 were treated with cementless prosthesis. Twenty-three patients had a retained hardware that had to be removed. Nonprimary cementless components were used in 22 (25%) femurs. In 21 (23%) hips, osteotomy was required to properly fit the cementless stem in the femur. At the time of latest follow-up (4 years on average), functional scores showed significant improvement. Radiographically, all femoral components showed stable bone ingrowth except 2 hips (3.5%) with stable fibrous ingrowth and 1 hip (2%) with loosening. There were 2 (3.5%) revisions in 2 patients for periprosthetic fracture and femoral loosening. The mechanical failure rate was 9% (5 hips). Despite technical difficulties, cementless femoral reconstruction provides a reliable and durable result in patients with proximal femoral deformity.

Over 25 years survival after Charnley's total hip arthroplasty.

BACKGROUND: Since 1962, the low friction arthroplasty (LFA) developed by Sir John Charnley has spread widely throughout the world. Many series have reported long-term results. Polyethylene (PE) wear is well known. The average wear ratio is about 0.1 mm a year. Many factors may influence that wear process. PURPOSE: The authors describe two different series of patients operated upon with Charnley's total hip arthroplasty (THA) using the original cemented stem and a non modular 22.2-mm head, with a cemented full polyethylene acetabular socket. Outcomes confirm excellent patient function after 25 years. They emphasise the fact that PE is the weak point of total hip arthroplasty. Function may be excellent even though PE wear is significant. In several cases, no wear at the maximum follow-up was detectable. RESULTS: This study confirms different publications relating long-term follow-up with LFA. During a Charnley meeting in Lyon, we published a survival curve of 85% after 25 years. Berry et al. published a 86.5% survival curve (J Bone Joint Surg Am 84:171-177, 2002). In 1995, Luc and Marcel Kerboul published a 77% survival rate after 20 years in young patients under 40 years old at the time of the surgery. In 2009, Callaghan et al. published a series of 35 years follow-up with a ratio of 78% survivorship (J Bone Joint Surg Br 91:2617-2621). CONCLUSION: Could the long-term results be improved? Through recent decades, many solutions have been introduced to improve the survivorship of THA including bearing surfaces such as alumina-on-alumina and metal-on-metal. Different problems have occurred with these solutions. LFA might be improved by working on the nature and the quality of the head. Improvements might also be obtained by working on the quality and the hardness of the acetabular socket.

Impingement Between the Metal Stem and the Ceramic Liner in Total Hip Arthroplasty: The Neck Is Not the Only Place Where Impingement Occurs.

BACKGROUND: It is assumed that impingement between the ceramic liner and the stem increases the possibility of a liner fracture in total hip arthroplasty with a ceramic-on-ceramic bearing. The purpose of this study was to analyze the pattern of the impingement by evaluating the notches (U-shaped indented wear scars engraved on the stem) on radiographs to determine when and where impingement develops and to analyze the factors affecting its occurrence. METHODS: Among the primary total hip arthroplasty cases using a ceramic-on-ceramic bearing performed from November 1997 to December 2003, 244 cases of 197 patients (123 male patients and 74 female patients) that had follow-up of ≥15 years were included. All of the radiographs were examined with special regard to the notches and the cup positions. RESULTS: Notches were detected at 77 sites of 57 cases (23.4%) for the first time between 8 months and 14.8 years after the surgical procedure. They were located on the neck or the shoulder of the stem. Shoulder notches were detected only in the cases with a short-neck head. Shoulder notches were found in 29 cases (20.0% of short-neck cases). Cup inclination was lower (p = 0.01) and anteversion was higher (p = 0.01) in the group with notches than the group without notches. There were 5 cases of ceramic head fracture. One of them experienced another ceramic liner fracture, assumed to be caused by prosthetic shoulder impingement, after the revision surgical procedure. CONCLUSIONS: The results of this study suggest that impingement between the stem and the ceramic liner occurs in a considerable proportion of patients who underwent total hip arthroplasty not only on the neck but also on the shoulder of the stem. Forceful and abrupt impingement on the stem shoulder can cause ceramic liner fracture. Impingement between the stem shoulder and the ceramic liner should be considered in designing a stem. It seems to be prudent to recommend that patients avoid squatting or sitting cross-legged on the floor as much as possible. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

THA with Delta ceramic on ceramic: results of a multicenter investigational device exemption trial.

UNLABELLED: Although the published studies on the outcomes of total hip arthroplasty (THA) performed with currently available ceramic components show high survivorship and low bearing wear at midterm followup, concern over ceramic fracture and squeaking persist. For these reasons, the use of ceramic is limited. Recently, a new alumina matrix composite material (Delta ceramic) with improved material properties was developed to address these concerns. We report the early outcomes and complications of a prospective, randomized, multicenter trial of 263 patients (264 hips) at eight centers, comparing a Delta ceramic-on-ceramic (COC) articulation with a Delta ceramic head-crosslinked polyethylene bearing combination (COP). There were 177 COC hips and 87 COP hips. Complications were reported for all patients, whereas clinical and radiographic results were provided for the 233 patients with minimum 2-year followup (average, 31.2 months; range, 21-49 months). The Harris hip scores and clinical, radiographic, and survivorship outcomes were similar in both groups. There were four (2%) revisions in the COC group and two (2%) in the COP group. We encountered three intraoperative ceramic liner-related events. In addition, one patient receiving the COC underwent revision for chipping of the ceramic liner, and a second had ceramic fragmentation on followup radiographs but has not undergone revision. These liner related complications remain a concern. No patient reported squeaking in either group; this leaves us hopeful the new material will lessen the frequency of squeaking. In the short term, the Delta COC articulation provided similar functional scores and survivorship and complication rates with the ceramic head mated with crosslinked polyethylene. LEVEL OF EVIDENCE: Level I, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Physical Therapists and Physicians Evaluate Nonarthritic Hip Disease Differently: Results From a National Survey.

BACKGROUND: Physical therapy and surgery are viable treatment options for nonarthritic hip disease (NAHD). Interdisciplinary collaboration can help patients make informed treatment decisions. Understanding how each provider can contribute is a critical first step in developing collaborative evaluation efforts. OBJECTIVE: The objective of this study was to describe the current evaluation of NAHD by both physical therapists and physicians, and evaluate national use of expert-recommended evaluation guidelines. DESIGN: A national survey study distributed in the United States was implemented to accomplish the objective. METHODS: A survey was distributed to 25,027 potential physical therapist and physician respondents. Respondents detailed their evaluation content for patients with NAHD across the following domains: patient-reported outcomes, patient history, special tests, movement assessment, clinical tests, and imaging. Respondents ranked importance of each domain using a 5-point Likert scale (not important, slightly important, important, very important, or extremely important). Odds ratios (ORs [95% CIs]) were calculated to identify the odds that physical therapists, compared with physicians, would report each evaluation domain as at least very important. Fisher exact tests were performed to identify statistically significant ORs. RESULTS: Nine hundred and fourteen participants (3.6%) completed the survey. Physical therapists were more likely to indicate movement assessment (OR: 4.23 [2.99-6.02]) and patient-reported outcomes (OR: 2.56 [1.67-3.99]) as at least very important for determining a diagnosis and plan of care. Physical therapists had lower odds of rating imaging (OR: 0.09 [0.06-0.14]) and special tests (OR: 0.72 [0.53-0.98]) as at least very important compared with physicians. LIMITATIONS: This survey study did not include many orthopedic surgeons and thus, primarily represents evaluation practices of physical therapists and nonsurgical physicians. CONCLUSIONS: Physical therapists were more likely to consider movement assessment very important for the evaluation of patients with NAHD, whereas physicians were more likely to consider imaging and special testing very important.

Antibiotic-laden cement wrap: A simple but effective way of treating patients with megaprosthesis infection.

Infection is one of the commonest causes for megaprosthesis failure. The current treatment includes antibiotics but no surgery, debridement, prosthesis removal and joint fusion, prosthesis revision or amputation. Success in controlling infection may be less than 50% in implant revision. The overall risk of amputation is more than 20%. We believe that repeated debridement with antibiotic-laden cement wrap (ALCW) may be a reliable alternative for managing the megaprosthesis infection. The purposes of this article are to identify whether ALCW is an effective way of eradicating the megaprosthesis infection, the associated complications and the functional outcome after management by ALCW. METHODS: This was a retrospective study of patients with megaprosthesis infection. From January 2014 to June 2016, there were five patients with tumour megaprosthesis infection who had undergone the ALCW procedure. Ages ranged from 17 to 59 years of age. Male to female ratio was 4:1. The patients studied had humeral (1), proximal femoral (1), distal femoral (1) and proximal tibial (2) prostheses. All patients had follow-ups more than 1 year (21-52 months) after treatment. RESULTS: All patients recovered from their implant infection and the implants were retained in all patients. There was no sign of infection in the most recent follow-up. One patient died of osteosarcoma recurrence. One patient had a large block of cement causing plastic insert dislodgement in the shoulder joint 1 year after surgery. Another patient with a dislocated hip cup had revision carried out in the final debridement. The most recent Musculoskeletal Tumor society (MSTS) scores ranged from 21 to 30. All patients were satisfied with their treatment. CONCLUSIONS: In this preliminary report of a small number of patients, ALCW has achieved 100% infection control. ALCW may be an easy and effective alternative for managing the megasprosthesis infection. The complications associated can be avoidable. The functional outcome is excellent.

T2 mapping with 3.0 T MRI of the temporomandibular joint disc of patients with disc dislocation.

INTRODUCTION: T2 mapping, as a quantitative biochemical MRI-technique that provides information on water and collagen fiber content and composition, was shown to be clinically feasible for the evaluation of healthy temporomandibular joints. OBJECTIVES: The aim of our study was to compare the T2 values of whole discs in patients with and without disc dislocation, to evaluate the possible influence of morphological findings on T2 values and to assess the interrater agreement. METHODS: Sixty-six patients were included in the study. Three experienced examiners assessed the perceptibility of the morphological parameters and the position of the articular disc on the morphological MR images. On the T2 maps, the T2 values of the region-of-interest (ROI) were assessed. RESULTS: The ICC (Intraclass Correlation Coefficient) for the reproducibility of the T2 values was 0.717. The assessment of the morphologic parameters was excellent or good in most of the discs. There was no significant difference in the T2 values based on disc position or signal intensity. But, a statistically significant moderation effect (p = .014) could be identified, indicating that the effect of disc position differs for different signal intensities. Condyle position, effusion, and degenerative changes showed pronounced moderation effects on the T2 values. CONCLUSION: Due to the high sensitivity to effusion, T2 mapping currently seems to be unsuitable as a diagnostic tool for routine use in the temporomandibular joint. The moderation effect clearly shows the influence of factors such as signal intensity, effusion, arthrosis, and condyle position. Perhaps a solution for these problems could be the development of dedicated TMJ coils for higher field strengths at 7.0 T.

Computed tomographic features of incomplete ossification of the canine humeral condyle.

OBJECTIVES: To describe computed tomographic (CT) features of canine elbows with incomplete ossification of the humeral condyle (IOHC) and investigate co-existing incongruence in the elbow joint. STUDY DESIGN: Case control study. ANIMALS: Dogs with IOHC (n=20; 38 elbows) and 25 normal elbows. METHODS: Elbows with IOHC and normal elbows were assessed by CT. Standardized dorsal and sagittal reconstructions were created at 3 levels using image analysis software to obtain single measurements of the humero-radial and humero-ulnar joint spaces. On dorsal plane reconstructions, joint space measurements were obtained at the center point of the humero-radial and humero-ulnar articulations. Joint incongruity was defined as the difference between the humero-radial and the humero-ulnar joint spaces. RESULTS: Nineteen dogs (95%), all Spaniel breeds, had either bilateral IOHC demonstrable as a saw-toothed intercondylar complete or incomplete hypoattenuating defect with hyperattenuating margins, or IOHC with contralateral humeral condylar fracture (HCF). Joint incongruity values for IOHC were compared with those of normal elbows. Significant differences were noted at the levels of the medial coronoid apex (P<.0001) and base (P<.004) indicative of humero-ulnar incongruence. Evidence of medial coronoid disease in 10 elbows (26%) and degenerative joint disease in 30 elbows (79%) was also found. CONCLUSIONS: Presence of elbow incongruence may be an underlying factor in failure of ossification centers to fuse leading to IOHC. CLINICAL RELEVANCE: IOHC is clearly defined by CT, and it should be considered in larger Spaniel breeds, with a chronic forelimb lameness or HCF.

[The horse as an athlete: an animal model of choice for sports medicine: sonographic studies of joint disorders]. / Le cheval athlète, modèle animal de choix en médecine du sport: l'apport de l'echographie en pathologie articulaire.

Equine diagnostic sonography was initially used for the diagnosis and documentation of tendon injuries. Since 1990, this technique, along with radiography, has become an indispensable imaging procedure for the diagnosis of equine joint injuries. Sonography provides precise diagnostic information on the synovial membrane and fluid, the articular cartilage, subchondral bone and joint margins, the ligaments and menisci, and the anatomical structures involved in periarticular swelling or enlargement. Improvements in ultrasound machines and better superficial and deep image resolution allow us to examine every joint of the frontlimbs and hindlimbs, including the most proximal, as well as most of the joints of the equine vertebral column, pelvis and head. As a professional athlete, the horse is an excellent animal model of sport-related joint disorders in humans. The large size of its anatomical structures facilitates high-quality imaging. Sensitive and specific diagnostic sonography of joint injuries requires strict standardization of the technical approach to each joint structure and also a precise knowledge of equine joint anatomy.

Wear rate and medium-term survival of a cemented, moderately cross-linked polyethylene acetabular prosthesis.

INTRODUCTION: The moderately cross-linked Depuy Marathon® cemented acetabular component was introduced into the UK in 2007. The wear rate for the previously introduced Marathon® uncemented acetabular component has been reported to range from 0.06 to 0.01 mm/year. The aim of this study was to present the medium-term results and wear rate of the Marathon® cemented prosthesis used in primary total hip arthroplasty. METHODS: 103 Marathon® cemented acetabular components were implanted between 2008 and 2009 in primary arthroplasty, who were eligible for this study. All patients received a metal 28-mm head. Mean age was 68 years (range 27-87). Mean clinical follow-up was 55 months (range 50-61). Mean radiological follow-up was 46 months (range 24-57). Wear was calculated on AP radiographs using computer-assisted uni-radiographic technique. RESULTS: The mean wear was 0.37 mm (range 0.0-0.78 mm). The wear rate was calculated as 0.03 mm/year (95% confidence interval 0.02-0.06). Postoperative complications included deep vein thrombosis (2%) and dislocation (0.8%); there were no deep infections. There were no revisions for failure of the Marathon® cemented acetabular component. CONCLUSIONS: The Marathon® cemented acetabular component demonstrates satisfactory wear rates and survivorship at medium-term follow-up.