Alain Chevrot

Capacity of the Clinical Picture to Characterize Low Back Pain Relieved by Facet Joint Anesthesia: Proposed Criteria to Identify Patients With Painful Facet Joints

Study Design. Prospective randomized study to compare the efficacy of facet joint injection with lidocaine and facet joint injection with saline in two groups of patients with low back pain, with and without clinical criteria that were determined in a previous study to implicate the facet joint as the primary source of the pain. Objectives. To assess the efficacy of single facet joint anesthesia versus placebo (saline injections) and to determine clinical criteria that are predictive of significant relief of LBP after injection. Summary of Background Data. There is no syndrome that discriminates between lower back pain caused by facet joint and that caused by other structures. Single or double facet joint anesthesia, and single photon emission computed tomography are expensive and time‐consuming procedures for selecting patients in controlled clinical trials with large populations. Methods. Results of a previous study showed that seven clinical characteristics were more frequent in patients who responded to facet joint anesthesia than in those who did not. In the current study, a group of 43 patients with lower back pain who met at least five criteria were compared with 37 patients who met fewer criteria. Patients randomly received injection of either lidocaine or saline into the lower facet joints. The result was considered positive if more than 75% pain relief was determined by visual analog scale. The patient, the radiologist, and the investigator were blinded. An analysis of variance was used to seek an interaction between clinical group effect and injection effect, and logistic regression analysis to select the best set of variables that would be predictive of minimum pain relief of 75% after the injection. Results. There was a significant interaction between clinical group and injection effect (P= 0.003). In patients with back pain, lidocaine provided greater lower‐back pain relief than saline (P = 0.01). Lidocaine also‐provided greater pain relief in the back pain group than in the the nonpain group (P = 0.02). The presence of five among seven variables (age greater than 65 years and pain that was not exacerbated by coughing, not worsened by hyperextension, not worsened by forward flexion, not worsened when rising from flexion, not worsened by extension‐rotation, and well‐relieved by recumbency), always including the last item, distinquished 92% of patients responding to lidocaine injection and 80% of those not responding in the lidocaine group. Conclusions. A set of five clinical characteristics can be used in randomized studies to select lower back pain that will be well relieved by facet joint anesthesia. These characteristics should not, however, be considered as definite diagnostic criteria of lower back pain originating from facet joints.

Intervertebral Disc Degeneration: The Role of the Mitochondrial Pathway in Annulus Fibrosus Cell Apoptosis Induced by Overload

Degeneration of the intervertebral disk (IVD) is a major pathological process implicated in low back pain and is a prerequisite to disk herniation. Although mechanical stress is an important modulator of the degeneration, the underlying molecular mechanism remains unclear. The association of human IVD degeneration, assessed by magnetic resonance imaging, with annulus fibrosus cell apoptosis and anti-cytochrome c staining revealed that the activation of the mitochondria-dependent apoptosome was a major event in the degeneration process. Mouse models of IVD degeneration were used to investigate the role of the mechanical stress in this process. The application of mechanical overload (1.3 MPa) for 24 hours induced annulus fibrosus cell apoptosis and led to severe degeneration of the mouse disks. Immunostaining revealed cytochrome c release but not Fas-L generation. The role of the caspase-9-dependent mitochondrial pathway in annulus fibrosus cell apoptosis induced by overload was investigated further with the use of cultured rabbit IVD cells in a stretch device. Mechanical overload (15% area change) induced apoptosis with increased caspase-9 activity and decreased mitochondrial membrane potential. Furthermore, Z-LEHD-FMK, a caspase-9 inhibitor, but not Z-IETD-FMK, a caspase-8 inhibitor, attenuated the overload-induced apoptosis. Our results from human samples, mouse models, and annulus fibrosus culture experiments demonstrate that the mechanical overload-induced IVD degeneration is mediated through the mitochondrial apoptotic pathway in IVD cells.

Radiological hand involvement in systemic sclerosis

Background: The osteoarticular and soft tissue structures of the hand may be involved in systemic sclerosis (SSc), causing functional disability. Objective: To assess radiological hand features in a cross sectional study of SSc patients and in controls. Methods: Hand radiology was done systematically in patients with SSc seen over a two year period and in unselected controls with rheumatoid arthritis or digital trauma. Two independent investigators blind to the diagnosis carried out the radiological assessment. Results: 120 consecutive SSc patients (median (range) age, 56.5 (20 to 90) years; disease duration, 6 (0 to 42) years) and 42 controls (22 with rheumatoid arthritis and 20 with digital trauma) were studied. Radiological abnormalities in SSc patients included erosion (21%), joint space narrowing (28%), arthritis (defined by concomitant erosion and joint space narrowing) (18%), radiological demineralisation (23%), acro-osteolysis (22%), flexion contracture (27%), and calcinosis (23%). In univariate and multivariate analysis, the resorption of distal phalanges was significantly associated with digital ulcers, extra-articular calcification, and pulmonary arterial hypertension; flexion contracture was associated with the diffuse cutaneous form and high HAQ (Health Assessment Questionnaire) disability score. Calcinosis was most often seen in patients with digital ulcers, but was similarly observed in patients with the diffuse or limited cutaneous subtypes. Conclusions: Flexion contracture was associated with disability and occurred in patients with the diffuse cutaneous subtype of SSc, consistent with the tendency towards fibrosis and functional impairment of this subtype. Calcinosis and acro-osteolysis were both associated with vascular complications, highlighting a potential role of vascular injury in such lesions.

Sonographic Appearance of Trigger Fingers

Objective. The purpose of this study was to describe the sonographic appearance of the first annular (A1) pulley–flexor tendon complex in patients with trigger fingers. Methods. Thirty‐three trigger fingers in 33 patients were examined with a 7‐ to 15‐MHz probe. A control group consisted of 20 patients without trigger fingers. The study included systematic measurement of the thickness of the A1 pulley and a power Doppler assessment of the pulleys, tendons, and tendon sheaths. Results. Thickening and hypoechogenicity of the A1 pulley were found in all patients with trigger fingers. Measurements of A1 pulley thickness were significantly different (P < .0001) between the groups without trigger fingers (mean, 0.5 mm; range, 0.4–0.6 mm) and with trigger fingers (mean, 1.8 mm; range, 1.1–2.9 mm). Hypervascularization of the A1 pulley on power Doppler imaging was found in 91% of the trigger fingers but was never found in the healthy control group. Flexor tendinosis was found in 48% of the trigger fingers; tenosynovitis was found in 55%; and both were found in 39%. In the control group, tenosynovitis and tendinosis were not found. Conclusions. Thickening and hyper‐vascularization of the A1 pulley are the hallmarks of trigger fingers on sonography. Other frequently observed features include distal flexor tendinosis and tenosynovitis.

Juxtaacetabular ganglionic (or synovial) cysts: CT and MR features

Radiographic findings include supraacetabular bone erosions, subchondral acetabular cysts, soft tissue masses with or without radiolucent inclusions representing nitrogen gas, joint space narrowing, and abnormal hip configuration. Associated tears of the acetabular labrum were confirmed by arthrography in two patients. Computed tomography and magnetic resonance imaging afforded improved delineation of soft tissue ganglia and their relationship to the acetabular bone, labrum, and hip joint. We report our experience with seven patients in whom various imaging examinations clearly documented the presence of soft tissue cystic lesions adjacent to the acetabulum; in six of the seven patients, significant clinical manifestations were evident in the affected hip. Such cysts, whether designated synovial or ganglionic in type, appear to be a frequently overlooked yet important cause of hip symptomatology.

Cervical spine and crystal-associated diseases: imaging findings

The cervical spine may be specifically involved in crystal-associated arthropathies. In this article, we focus on the three common crystals and diseases: hydroxyapatite crystal deposition disease, calcium pyrophosphate dihydrate (CPPD) deposition disease, and monosodium urate crystals (gout). The cervical involvement in crystal-associated diseases may provoke a misleading clinical presentation with acute neck pain, fever, or neurological symptoms. Imaging allows an accurate diagnosis in typical cases with calcific deposits and destructive lesions of the discs and joints. Most of the cases are related to CPPD or hydroxyapatite crystal deposition; gout is much less common.

Epidural lipomatosis. Interest of magnetic resonance imaging in a weight-reduction treated case.

An obese patient with bilateral sciatic pain had epidural lipomatosis on magnetic resonance examination. Treatment that used a weight-reduction program eliminated the symptoms, and after magnetic resonance imaging, revealed reduction of the lipomatosis deposits.

Closed ruptures of the flexor digitorum tendons: MRI evaluation

Abstractu2002Objective. To assess the MRI findings in cases of closed rupture of the flexor digitorum tendons (FDT). Patients and design. Ten patients with a clinical suspicion of rupture of FDT underwent MRI before surgery. None of the patients presented a skin injury. Fingers were imaged using axial T1-weighted SE sequences, three-dimensional GE images, and curved reconstructions. Results. Twelve FDT had surgical confirmation of rupture. Flexor digitorum profundus (FDP) and flexor pollicis longus (FPL) tendons were more frequently ruptured (n=8) than flexor digitorum superficialis (FDS) tendons (n=4). MR images accurately depicted the level of the rupture. The gap between the tendon ends (mean 45 mm, range 21–70 mm) was assessed best with curved reconstructions and was well correlated with the surgical findings. The proximal end mainly retracted into the palm or the carpal tunnel (n=8), and less frequently into the digital canal (n=4). In two cases, the proximal end curled up in the palm, clinically simulating a rupture of a lumbrical muscle in one case. MRI also showed the appearance of the adjacent tendons. Conclusion. MRI accurately depicted the level of rupture and the gap between the tendon ends, which assisted the surgical choice between suture, graft or tendon transfer.

Inflammation and cancer, the mastocytoma P815 tumor model revisited: Triggering of macrophage activation in vivo with pro-tumorigenic consequences

Subcutaneous in vivo injections of cells of the mastocytoma line P815 in syngenic DBA/2 mice induce locally fast growing solid tumors. These have been used extensively as a cancer model to analyze and manipulate the relationship between tumor cells and hosts immune defenses. We report that progression of P815 tumors in vivo was accompanied by a burst (Days 5–7) of local inflammatory cells recruitment and angiogenesis observed histologically, corroborated in vivo by MRI with gadolinium, overtranscription of macrophage activation marker genes, secretion of TNF‐α by regional lymph node cells and concomitant systemic inflammation. No substantial overtranscriptions of either VEGF or IL‐10 or TGF‐β genes were observed. Induction of COX‐2 gene was a late event. To establish a possible relationship between the tumor‐induced local, regional and systemic increase of pro‐inflammatory mediators and progression of tumors in vivo, we carried out experiments deliberately modulating the inflammatory status of the recipient animals. Pretreatment of recipient animals by i.p. injection of thioglycolate accelerated P815 tumor growth. At the opposite, treatment of mice with either a COX‐1 + COX‐2 inhibitor (aspirin, 1 mg/day/mouse) or a specific COX‐2 inhibitor (celecoxib, 0.13 mg/day/mouse) for 2 weeks after injection of tumor cells, significantly reduced the size and growth rate of tumors compared to control mice. Experiments carried out in vitro indicated that peritoneal macrophages from untreated animals were strongly activated by live P815 cells and by P815 membrane preparations. The tumor‐induced inflammatory reaction could establish a local micro environment favoring tumor progression. The P815 tumor model might be helpful to recognize important factors controlling host/tumor relationship.

Fractures of the ankylosed spine: MDCT and MRI with emphasis on individual anatomic spinal structures.

OBJECTIVEnThe purpose of this article is to illustrate the spectrum of MDCT and MRI appearances of spinal fractures in ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis.nnnCONCLUSIONnSpinal fractures associated with ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis usually involve the three columns of the spine, and injury to the posterior osteoligamentous component is the hallmark of these fractures. Osseous and ligamentous injuries can be accurately visualized and analyzed with MDCT with multiplanar reformation and with MRI.