Radiographic total disc replacement angle measurement accuracy using the Oxford Cobbometer: precision and bias.

Total disc replacement (TDR) clinical success has been reported to be related to the residual motion of the operated level. Thus, accurate measurement of TDR range of motion (ROM) is of utmost importance. One commonly used tool in measuring ROM is the Oxford Cobbometer. Little is known however on its accuracy (precision and bias) in measuring TDR angles. The aim of this study was to assess the ability of the Cobbometer to accurately measure radiographic TDR angles. An anatomically accurate synthetic L4-L5 motion segment was instrumented with a CHARITE artificial disc. The TDR angle and anatomical position between L4 and L5 was fixed to prohibit motion while the motion segment was radiographically imaged in various degrees of rotation and elevation, representing a sample of possible patient placement positions. An experienced observer made ten readings of the TDR angle using the Cobbometer at each different position. The Cobbometer readings were analyzed to determine measurement accuracy at each position. Furthermore, analysis of variance was used to study rotation and elevation of the motion segment as treatment factors. Cobbometer TDR angle measurements were most accurate (highest precision and lowest bias) at the centered position (95.5%), which placed the TDR directly inline with the x-ray beam source without any rotation. In contrast, the lowest accuracy (75.2%) was observed in the most rotated and off-centered view. A difference as high as 4 degrees between readings at any individual position, and as high as 6 degrees between all the positions was observed. Furthermore, the Cobbometer was unable to detect the expected trend in TDR angle projection with changing position. Although the Cobbometer has been reported to be reliable in different clinical applications, it lacks the needed accuracy to measure TDR angles and ROM. More accurate ROM measurement methods need to be developed to help surgeons and researchers assess radiological success of TDRs.

Importance of polyethylene thickness in total shoulder arthroplasty: a finite element analysis.

BACKGROUND: Articular surfaces reconstruction is essential in total shoulder arthroplasty. Because of the limited glenoid bone support, thin glenoid component could improve anatomical reconstruction, but adverse mechanical effects might appear. METHODS: With a numerical musculoskeletal shoulder model, we analysed and compared three values of thickness of a typical all-polyethylene glenoid component: 2, 4 (reference) and 6mm. A loaded movement of abduction in the scapular plane was simulated. We evaluated the humeral head translation, the muscle moment arms, the joint force, the articular contact pattern, and the polyethylene and cement stress. Findings Decreasing polyethylene thickness from 6 to 2mm slightly increased humeral head translation and muscle moment arms. This induced a small decreased of the joint reaction force, but important increase of stress within the polyethylene and the cement mantel. Interpretation The reference thickness of 4mm seems a good compromise to avoid stress concentration and joint stuffing.

Treatment of adult-onset Still's disease: a review

Adult-onset Still's disease (AOSD) is a rare inflammatory disorder that has been recently classified as a polygenic autoinflammatory disorder. The former classification, based on the disease course, seems to be quite dated. Indeed, there is accumulating evidence that AOSD can be divided into two distinct phenotypes based on cytokine profile, clinical presentation, and outcome, ie, a "systemic" pattern and an "articular" pattern. The first part of this review deals with the treatments that are currently available for AOSD. We then present the different strategies based on the characteristics of the disease according to clinical presentation. To do so, we focus on the two subsets of the disease. Finally, we discuss the management of life-threatening complications of AOSD, along with the therapeutic options during pregnancy.

Partial cricotracheal resection in children weighing less than 10 kilograms.

OBJECTIVES: To assess the long-term outcome, safety, and efficacy of partial cricotracheal resection (PCTR) for subglottic stenosis in a group of children and infants weighing less than 10 kg at the time of the surgery. STUDY DESIGN: Historical cohort study. SETTING: Academic tertiary medical center. SUBJECTS AND METHODS: Thirty-six children weighing less than 10 kg at the time of the surgery were compared to a group of 65 children who weighed more than 10 kg. The Kaplan Meier method and Cox regression were carried out to detect differences in decannulation time and rates and to examine the influence of various parameters (i.e., comorbidities, type of surgery, and complications requiring revision surgery) at the time of decannulation. Evaluation of the long-term outcome was based on questionnaires assessing breathing, voice, and swallowing. RESULTS: Decannulation rate was 92 percent (33/36) for the group of children weighing less than 10 kg. No significant differences were found between the two body weight groups with respect to the aforementioned covariates. The median follow-up period was nine years (range, 1-23 yrs). Questionnaire responses revealed completely normal breathing and swallowing in 72 percent and 90 percent of the children, respectively. Seventy-one percent of the patients considered their voice to be rough or weak. CONCLUSION: PCTR in infants and children weighing less than 10 kg is a safe and efficient technique with similar long-term results when compared to results seen in older and heavier children.

Evolutionary comparison provides evidence for pathogenicity of RMRP mutations.

Cartilage-hair hypoplasia (CHH) is a pleiotropic disease caused by recessive mutations in the RMRP gene that result in a wide spectrum of manifestations including short stature, sparse hair, metaphyseal dysplasia, anemia, immune deficiency, and increased incidence of cancer. Molecular diagnosis of CHH has implications for management, prognosis, follow-up, and genetic counseling of affected patients and their families. We report 20 novel mutations in 36 patients with CHH and describe the associated phenotypic spectrum. Given the high mutational heterogeneity (62 mutations reported to date), the high frequency of variations in the region (eight single nucleotide polymorphisms in and around RMRP), and the fact that RMRP is not translated into protein, prediction of mutation pathogenicity is difficult. We addressed this issue by a comparative genomic approach and aligned the genomic sequences of RMRP gene in the entire class of mammals. We found that putative pathogenic mutations are located in highly conserved nucleotides, whereas polymorphisms are located in non-conserved positions. We conclude that the abundance of variations in this small gene is remarkable and at odds with its high conservation through species; it is unclear whether these variations are caused by a high local mutation rate, a failure of repair mechanisms, or a relaxed selective pressure. The marked diversity of mutations in RMRP and the low homozygosity rate in our patient population indicate that CHH is more common than previously estimated, but may go unrecognized because of its variable clinical presentation. Thus, RMRP molecular testing may be indicated in individuals with isolated metaphyseal dysplasia, anemia, or immune dysregulation.

Partial Cricotracheal Resection in Children: Potential Pitfalls and Avoidance of Complications.

OBJECTIVES: To delineate the various factors contributing to failure or delay in decannulation after partial cricotracheal resection (PCTR) in children. STUDY DESIGN: Case series. SETTING: Academic tertiary medical center. SUBJECTS AND METHODS: A retrospective case review of 100 children who underwent PCTR between 1978 and 2008 for severe subglottic stenosis using an ongoing database. RESULTS: Ninety of 100 (90%) patients were decannulated. Six patients needed secondary tracheostomy. The results of the preoperative evaluation showed grade II stenosis in four patients, grade III in 64 patients, and grade IV in 32 patients. The overall decannulation rate was 100 percent in grade II, 95 percent in grade III, and 78 percent in grade IV stenosis. Fourteen (14%) patients required revision open surgery. The most common cause of revision surgery was posterior glottic stenosis. Partial anastomotic dehiscence was seen in four patients. Delayed decannulation (>1 year) occurred in nine patients. Overall mortality rate in the whole series was 6 percent. No deaths were directly related to the surgery. No iatrogenic recurrent laryngeal nerve injury was present in the entire series. CONCLUSION: Comorbidities and associated syndromes should be addressed before PCTR is planned to improve the final postoperative outcome in terms of decannulation. Perioperative morbidity due to anastomotic dehiscence, to a certain extent, can be avoided by intraoperative judgment in the selection of double-stage surgery when more than five tracheal rings need to be resected. Subglottic stenosis with glottic involvement continues to pose a difficult challenge to pediatric otolaryngologists, often necessitating revision procedures.

The temporoparietal fascia flap: a versatile tool in head and neck reconstruction.

PURPOSE OF REVIEW: The article reviews recent significant advances and current applications of the temporoparietal fascia flap (TPFF) in head and neck surgery. RECENT FINDINGS: The recent literature describes a wide span of new applications of the TPFF in many areas. Significant developments and refinements in the reconstruction of orbitomaxillary composite defects and orbital exenteration cavities are reported. The TPFF combined with alloplastic framework is gaining in importance in external ear reconstruction. Innovative prefabricated skin or soft-tissue grafts based on the TPFF are used to restore facial contour or in the reconstruction of complex facial defects. The free TPFF finds a role in laryngotracheal reconstruction as a vascular carrier to support cartilage grafts. SUMMARY: Owing to its reliability and unequalled structural properties, the TPFF still plays a central role in facial reconstruction. Future investigation will likely incorporate the free TPFF as a vascular carrier of bioengineered tissues, such as cartilage and mucosa, for various head and neck indications.

BMP-2 and TGF-beta1 differentially control expression of type II procollagen and alpha 10 and alpha 11 integrins in mouse chondrocytes.

Bone morphogenetic protein (BMP)-2 and transforming growth factor (TGF)-beta1 are multifunctional cytokines both proposed as stimulants for cartilage repair. Thus it is crucial to closely examine and compare their effects on the expression of key markers of the chondrocyte phenotype, at the gene and protein level. In this study, the expression of alpha 10 and alpha 11 integrin subunits and the IIA/IIB spliced forms of type II procollagen have been monitored for the first time in parallel in the same in vitro model of mouse chondrocyte dedifferentiation/redifferentiation. We demonstrated that TGF-beta1 stimulates the expression of the non-chondrogenic form of type II procollagen, IIA isoform, and of a marker of mesenchymal tissues, i.e. the alpha 11 integrin subunit. On the contrary, BMP-2 stimulates the cartilage-specific form of type II procollagen, IIB isoform, and a specific marker of chondrocytes, i.e. the alpha 10 integrin subunit. Collectively, our results demonstrate that BMP-2 has a better capability than TGF-beta1 to stimulate chondrocyte redifferentiation and reveal that the relative expressions of type IIB to type IIA procollagens and alpha 10 to alpha 11 integrin subunits are good markers to define the differentiation state of chondrocytes. In addition, adenoviral expression of Smad6, an inhibitor of BMP canonical Smad signaling, did not affect expression of total type II procollagen or the ratio of type IIA and type IIB isoforms in mouse chondrocytes exposed to BMP-2. This result strongly suggests that signaling pathways other than Smad proteins are involved in the effect of BMP-2 on type II procollagen expression.

Avulsion fracture of the peroneus longus tendon insertion at the base of the first metatarsal: report of a case.

Isolated avulsion fracture of the peroneus longus tendon insertion at the base of the first metatarsal is very rare. Similar to most avulsion fractures that result from excessive strain at a tendon or ligament insertion, this type of injury is caused by the strong tension exerted by the peroneus longus tendon. The mechanisms leading to this lesion and treatment options are not clearly defined. We present the case of an isolated minimally displaced intra-articular avulsion fracture at the plantar lateral base of the first metatarsal. Faced with a painful non-union following conservative treatment we considered excision of the bony fragment and first tarsometatarsal arthrodesis. This leads to a favourable functional outcome.

Entorse aiguë de la Cheville: quelle immobilisation [Acute ankle sprain: which immobilization?]

Acute ankle sprain is the most frequent orthopaedic injury. Up to 4% of patients admitted to the emergency room will present with an acute ankle sprain. The lateral ligaments are involved at various degrees (anterior talo-fibular and calcaneo-fibular ligaments). Grade I acute ankle sprains are well treated with a compression bandage or an Aircast brace. Grade II and III acute ankle sprains are best treated with a below-knee cast. The Aircast brace is the next best treatment for such lesions (grades II and III) and will provide satisfactory support, but has been shown to be not as effective as the below-knee cast in terms of short to mid-term patients outcome (pain and function).

Résultats préliminaires de l'enclouage rétrograde de l'humérus [Preliminary results of retrograde nailing of the humerus]

A group of nine patients with a diaphyseal fracture of the humerus and treated with retrograde nailing were studied with a mean follow-up of 15.3 months. Six patients with a humeral fracture without neurological deficit showed a good shoulder and elbow mobility at the last visit. Three patients with neurological lesion preoperatively suffer from a diminished range of movement not related to the surgical procedure. During the operation and postoperatively we found no complication related to the implant and more precisely we could not find a iatrogenic fracture or nervous lesion except one intraoperative lesion of the radial nerve probably related to an important traction movement during reduction with complete remission. Consolidation has been achieved for all fractures but one. This patient suffers from a lesion of the brachial plexus with complete plegia of the arm and a vascular lesion. This patient had to be reoperated for an atrophic non-union by bone grafting and plate fixation. The retrograde nail is a good implant and must be considered in our treatment plans as much as conservative treatment or surgical treatment with plating, anterograde nailing or the use of an external fixator. Only then will we be able to give to the patient the most adapted treatment for his fracture.

Enchondromatosis revisited: New classification with molecular basis.

The so-called "enchondromatoses" are skeletal disorders defined by the presence of ectopic cartilaginous tissue within bone tissue. The clinical and radiographic features of the different enchondromatoses are distinct, and grouping them does not reflect a common pathogenesis but simply a similar radiographic appearance and thus the need for a differential diagnosis. Recent advances in the understanding of their molecular and cellular bases confirm the heterogeneous nature of the different enchondromatoses. Some, like Ollier disease, Maffucci disease, metaphyseal chondromatosis with hydroxyglutaric aciduria, and metachondromatosis are produced by a dysregulation of chondrocyte proliferation, while others (such as spondyloenchondrodysplasia or dysspondyloenchondromatosis) are caused by defects in structure or metabolism of cartilage or bone matrix. In other forms (e.g., the dominantly inherited genochondromatoses), the basic defect remains to be determined. The classification, proposed by Spranger and associates in 1978 and tentatively revised twice, was based on the radiographic appearance, the anatomic sites involved, and the mode of inheritance. The new classification proposed here integrates the molecular genetic advances and delineates phenotypic families based on the molecular defects. Reference radiographs are provided to help in the diagnosis of the well-defined forms. In spite of advances, many cases remain difficult to diagnose and classify, implying that more variants remain to be defined at both the clinical and molecular levels. © 2012 Wiley Periodicals, Inc.

A randomised controlled clinical trial and gait analysis of fixed- and mobile-bearing total knee replacements with a five-year follow-up.

This study compared the outcome of total knee replacement (TKR) in adult patients with fixed- and mobile-bearing prostheses during the first post-operative year and at five years' follow-up, using gait parameters as a new objective measure. This double-blind randomised controlled clinical trial included 55 patients with mobile-bearing (n = 26) and fixed-bearing (n = 29) prostheses of the same design, evaluated pre-operatively and post-operatively at six weeks, three months, six months, one year and five years. Each participant undertook two walking trials of 30 m and completed the EuroQol questionnaire, Western Ontario and McMaster Universities osteoarthritis index, Knee Society score, and visual analogue scales for pain and stiffness. Gait analysis was performed using five miniature angular rate sensors mounted on the trunk (sacrum), each thigh and calf. The study population was divided into two groups according to age (≤ 70 years versus > 70 years). Improvements in most gait parameters at five years' follow-up were greater for fixed-bearing TKRs in older patients (> 70 years), and greater for mobile-bearing TKRs in younger patients (≤ 70 years). These findings should be confirmed by an extended age controlled study, as the ideal choice of prosthesis might depend on the age of the patient at the time of surgery.

Complications et atteintes systémiques de la polyarthrite rhumatoïde [Complications and systemic manifestations of rheumatoid arthritis].

Rheumatoid arthritis (RA), in addition to the traditional joint damage can affect all organs as a systemic disease. Extra-articular manifestations of RA are highly variable ranging from rheumatoid nodules (most common) to rheumatoid vasculitis presenting a significant morbidity and mortality (49% at 5 years). With the new algorithms of treatment (earlier) and the use of biologics, the incidence of severe extra-articular manifestations decreases. Regarding the treatment of rheumatoid vasculitis, rituximab looks promising. RA also increases cardiovascular risk and the risk of osteoporosis. It is therefore important to identify these risks and, if appropriate, treat them. Collaboration with the general practitioner is essential in this situation.

Cable fixation and early total hip arthroplasty in the treatment of acetabular fractures in elderly patients.

Eighteen patients with acetabular fractures, with a mean age of 76 years, were treated with cable fixation and acute total hip arthroplasty. Nine were T-shaped fractures, 4 associated transverse and posterior wall, 2 transverse, 2 posterior column and posterior wall, and 1 anterior and posterior hemitransverse fractures. One patient experienced 3 episodes of hip dislocation within 10 months after surgery. All the others had a good outcome at a mean follow-up time of 36 months. Radiographic assessment showed healing of the fracture and a satisfactory alignment of the cup without loosening. This option provides good primary fixation, stabilizes complex acetabular fractures in elderly patients, and permits early postoperative mobilization.