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P Clavert

Publications and source records attributed to P Clavert.

18 recordsLinked to original sources
PubMed2006

New findings on intermetacarpal fat pads: anatomy and imaging.

Many studies have focused on the functional importance of the gliding structures of the hand. These structures are clinically important in reconstructive surgery and mechanically essential for an efficient hand grasp. The aims of this study were to first review the intermetacarpal space and then focus on its fatty tissue, the intermetacarpal fat pad. This study used dissections and histological analysis of fetal and adult hands and CT scans of adult hands. The intermetacarpal fat pads are well-defined adipose structures located between the heads of the second, third, fourth and fifth metacarpal bones. They are located in spaces defined by the palmar fascia and its deep expansions. These spaces are closed distally but open proximally into the tunnels surrounding the flexor tendons (Legueu and Juvara canals). The pads are composed of non-mobilizable fat; they protect the neurovascular pedicles of the fingers. They may act with the palmar skin to mitigate compressive and shear forces during gripping. Finally they may be involved in neurological symptoms if their size is increased by any trauma or inflammatory process.

Adipose Tissue↗
PubMed2006

[Adult lateral meniscus].

Meniscal lesion does not mean meniscectomy and this is particularly true for the lateral meniscus. The reputation of mildness of the meniscectomy is usurped. The rate of joint space narrowing after lateral meniscectomy is of 40% at a follow-up of 13 years compared to 28% for the medial meniscus (symposium SFA 1996). Several arguments explain those results: biomechanical: the lateral meniscus contributes to the congruence; particularly the lateral meniscus is the zone where antero-posterior translational during knee flexion is 12 mm. The pejorative effects of lateral meniscectomy have conducted, more though to the medial meniscus, to the concept of meniscal economy. Lateral meniscectomy must be as partial as possible. Particularly, a discoid meniscus presenting a complete tear should be treated by a meniscoplasty in order to shape the meniscus in a more anatomic form than a total meniscectomy. Lateral meniscectomy is indicated in complex or horizontal cleavage, symptomatic, on stable knees. A particular case is the cyst of the lateral meniscus. It is a cystic subcutaneous formation, usual consequence of a horizontal cleaved meniscus of which the particularity is that it opens besides the articulation. The strategy must not consist in the isolated treatment of the cyst. This pathology should be addressed by an arthroscopic meniscectomy reaching the meniscosynovial junction at the level of the cyst. Meniscal repair must be proposed every time if possible. Criteria of reparability are better studied on MRI. Preoperatively MRI is the first choice radiological exam. Two essential indications can be held back: the vertical peripheral longitudinal lesion is on the non-vascularized area, and the horizontal cleaving of the junior athlete (if the cleaving remains purely intra meniscal). Meniscal repair is highly performed when the meniscal tear is associated to a rupture of the ACL (simultaneous reconstruction of the LCA). Postoperative outcome is different of that of a "simple" arthroscopic meniscectomy. The healing process being slow, it suits to protect the suture by a splint in the first month, and with an exclusion of sports with knee torsion during 6 months. Functional results (absence of secondary meniscectomy) and anatomical results (reality of the cicatrisation) are good in 77% of cases (symposium of the French Society of Arthroscopy 2003) at a follow-up of 55 months. Survivorship analysis indicates that majority of the failures occur within two years: this testifies a default of primary cicatrisation. At the studied follow-up, meniscal repair was efficient to protect the cartilage. Lateral meniscus results are better that medial meniscus one. Those data support indications: All suspicion of meniscal lesion must have an MRI preoperatively to confirm the lesion, to localize her and to search criteria of reparability; All vertical longitudinal peripheral lesions can and must be repaired especially in young patients and children; All horizontal cleaving of the junior athletes should be treated by open repair; surgical abstention must be proposed when the lesion is non symptomatic, or when lesion is limited and associated to an ACL tear (in that case isolated ACL reconstruction is proposed), or when clinical symptoms are minimal; Meniscectomy, always arthroscopic, is proposed for a symptomatic lesion in the avascular zone or for a deep horizontal cleavage or a complex tear; Tear of the discoid meniscus should be treated by meniscoplasty. A painful knee after lateral meniscectomy might be due to a too limited initial meniscectomy: an iterative meniscectomy may be indicated or lateral femorotibial arthritis, especially after subtotal or total meniscectomy. In this last case and after failure of usual medical treatment such as viscosupplementation surgery may be indicated. Osteotomy in order to unload the lateral femorotibial compartment gives a partial response as the shearing forces remain. This osteotomy is indicated only if the lower limb axis is normal or in valgus. Meniscal allograft is an option in young patients in grade I or II arthritis. Results are promising. Rene Verdonk's series show a survivorship analysis of 75% at 7 years. Early diagnosis of a postmeniscectomy syndrome before cartilaginous lesions occur is essential for an adapted treatment. In conclusion, lateral meniscectomy are less frequent than those of the medial meniscus but their prognosis is less favorable. They should be early diagnosed (MRI). Treatment options are various: abstention, meniscectomy, and repair. Painful post lateral meniscectomy syndrome may be treated by a new surgical option: meniscal allograft.

Cysts↗
PubMed2005

[Transverse radioulnar branch of the dorsal ulnar nerve: anatomic description and arthroscopic implications from 45 cadaveric dissections].

PURPOSE OF THE STUDY: We conducted an anatomic study of the transverse branch of the dorsal ulnar nerve to describe its morphology and position in relation to arthroscopic exploration portals. MATERIAL AND METHODS: Forty-five non-side-matched anatomic specimens of unknown age and gender were preserved in formol. The dorsal branch of the ulnar nerve was identified and dissected proximally to distally in order to reveal the different terminal branches. The morphometric analysis included measurement of the length and diameter of the transverse branch and measurement of wrist width. We also measured the smallest distance between the transverse branch and the ulnar styloid process, and between the branch and usual arthroscopic portals (4-5, 6R, 6U) in the axis of the forearm. RESULTS: The transverse branch was inconstant. It was found in 12 of the 45 dissection specimens (27%). In two-thirds of the specimens, the branch ran over less than 50% of the wrist width, tangentially to the radiocarpal joint. Mean nerve diameter was 1 mm. It was found 5-6 mm from the ulnar styloid process and was distal to it in 83% of the specimens. The dissections demonstrated two anatomic variants. Type A corresponded to a branch running distally to the ulnar styloid process, parallel to the joint line (10/12 specimens). Type B exhibited a trajectory proximal to the ulnar styloid process, crossing the ulnar head (2/12 specimens). The relations with the arthroscopic portals (4-5, 6R, 6U) showed that the mean distance from the branch to the portal was 3.75 mm for the 4-5 portal (distally in 11/12 specimens), 3.68 mm for the 6R portal (distally in 10/12 specimens), and 4.83 mm for the 6U portal (distally in 7 specimens and proximally in 5). DISCUSSION: To our knowledge, there has been only one report specifically devoted to this transverse branch. Two other reports simply mention its existence. According to the literature, the transverse branch of the dorsal ulnar nerve occurs in 60-80% of the cases. We found two anatomic variations different than those described in the literature. Based on our findings and data reported previously, we propose a new classification, describing two main types. In Type 1, the transverse branch arises proximally to the ulnar styloid process;type 1A and type IB are described in relation to the direction of the branch. In Type II, the branch arises distally to the ulnar styloid process;type IIA and type IIB again being described in relation to the direction of the branch. On the tangential trajectory over the radiocarpal joint, the morphometric data show a zone of risk described by a rectangle measuring 10 mm wide (6 mm distal and 4 mm proximal to the ulnar styloid process) and covering 50% of the wrist width. The relations with arthroscopic portals describe a zone of risk corresponding to a 5-7 mm radius circle centered on the portals (4-5, 6R, 6U), which includes 83% of the transverse branches.

Arm↗
PubMed2005

[Not Available].

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Journal Article↗
PubMed2005

[Not Available].

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Journal Article↗
PubMed2005

[Not Available].

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Journal Article↗
PubMed2004

[A new implant for proximal humeral fracture: experimental study of the basket plate].

PURPOSE OF THE STUDY: We conducted a comparative study of three ostheosynthesis systems for proximal humeral fractures. The conclusions led to the elaboration of a rigid extramedullary osteosynthesis implant. This novel implant allows specific fixation of the tuberosities via six adjustable and removable hooks organized like a basket. There are two versions, with and without a central cephalic locking screw. We report two static biomechanical studies conducted to analyze this material. MATERIAL AND METHODS: The two studies were performed on fresh frozen cadaver specimens with known bone density and with an experimental model of a four-fragment fracture of the proximal humerus. The first tests were designed to measure axial pressure reproducing the physiological movement applying the most stress on the head of the humerus. This allowed a global analysis of the mechanical behavior of the implant and an assessment of the contribution of the central cephalic locking screw. The second series of tests were traction tests used to analyze the behavior of the tuberosities fixed with the hooks. We assess the assemblies by measuring the mechanical resistance: rigidity of the fixation was recorded in mm/100N. Pre- and post-procedure x-rays and photographs were obtained to allow a subjective assessment of fragment displacement. RESULTS: The first series of tests demonstrated that the implant, with the central cephalic locking screw, presented good overall mechanical properties. The notion of better stability of the tuberosities obtained with the hooks, as seen during the first tests, was reinforced by the data from the second tests, although no statistically significant difference was demonstrated. We also noted that there was no statistically significant correlation between bone density and the slopes of the force-resistance curves. DISCUSSION: This prototype implant has an overall mechanical resistance equivalent to the reference implant, with at least equivalent performance. Proof of the usefulness of the central locking screw was not established, even though improved tolerance to loading by better force distribution seemed apparent. The contribution of the hook basket was not demonstrated. Data from the observations do however suggest the expectations of the implant will be fulfilled. Tests conducted on a larger scale would probably demonstrate a difference. It is clear that the small number of implants used here limited the study. Comparison with data in the literature show that this new prototype is adapted to the mechanics of the proximal humerus. Resistant to physiological stress, the implant allows pendular movement and passive physical therapy during the early post-operative period.

Biomechanical Phenomena↗
PubMed2002

[Traumatic bilateral rotatory C1-C2 dislocation in an adult: case report and review of the literature].

Trauma led to bilateral rotatory atlantoaxial dislocation in a 23-year-old woman. Clinical diagnosis of this uncommon dislocation of the cervical spin is generally difficult and often made late. Typical signs include pain in the upper cervical spine and a fixed rotated position of the head. Integrity of the transverse ligament of the atlas is a determining factor for atlantoaxial stability and allows orthopedic treatment after reduction using moderate traction on the head. As for most authors, orthopedic was successful in our patient who totally recovered cervical spine mobility without pain.

Accidents, Traffic↗
PubMed2001

Effects of freezing/thawing on the biomechanical properties of human tendons.

Numerous biomechanical studies using osteoarticular complex need frozen cadaveric specimens. Some of these studies deal with the resistance of the tendinous structures, for example the resistance of some autografts, such as the patellar ligament and the semitendinosus and gracilis tendons for reconstruction of the anterior cruciate ligament. The aim of this study was the in-vitro evaluation of the mechanical modifications induced by freezing/thawing on human tendons. The long head of the biceps brachii tendon was used as the reference. Eight pairs of tendons of the long head of the biceps brachii were taken from eight fresh cadavers. After drawing lots, one was tested immediately, the other was deep-frozen and then thawed. With an Instron material-testing machine, we performed a relaxation test and a uniaxial tensile test, to estimate the ultimate tensile failure and the elastic modulus of each pair of tendons. Freezing had no influence on the tendinous relaxation, but altered significantly the ultimate tensile failure and Young's modulus of the tendons.

Adult↗
PubMed2001

[Reconstruction by graft and reinforcement device in severe aseptic acetabular loosening: 10 years survivorship analysis].

PURPOSE OF THE STUDY: We report our experience with the treatment of aceptic acetabular loosening with important loss of bone stock using a graft and a metallic reinforcement device. MATERIAL AND METHOD: We carried out a retrospective study on 56 acetabular revision arthroplasties with severe loss of bone stock performed between November 1980 and June 1992. Mean age of the 35 females and 19 males was 68.5 years. In all cases, there was a combined lesion (cavity + segmentary) of two roofs (type 3 or 4 in the SOFCOT classification). The superior wall was concerned in all cases (80 p. 100 with a combined lesion). Reconstruction was performed using grafts (autograft (n=15), allograft (n=39) or both (n=2)) covering more than 50 p. 100 of the socket. Structural grafts were embedded into the defects in case of superior combined lesion with extension to the anterior and the posterior walls. A morselized graft was used to fill other defects. The reinforcement device was a Müller ring (n=35) or the Burch-Schneider APC (n=21). Mean follow-up was 8.75 years (range 3 - 16 years). RESULTS: There were 29 iterative aseptic loosenings of acetabular component revised or non-revised (n=11). Twenty-four of these cases had a Müller ring and 5 had a Burch-Schneider APC. The 10-year cumulative survival rate (CSR) was 0.43 +/- 0.16 and the 11-year CSR was 0.350.16 using iterative aseptic loosening as the end point. The lateral position of the hip center (p=0.02), female gender (p=0.03), and the Müller ring (p=0.0054) were statistically negative factors. The 10-year CSR was 0.44 +/- 0.18 for the Müller ring and 0.78 +/- 0.1 for the Burch-Schneider APC, the difference being statistically significant (p=0.007). These two populations were strictly comparable. CONCLUSIONS: In case of important loss of bone stock, reconstruction by grafts is widely used as reported in the literature. A metallic reinforcement device must be used to protect the graft during incorporation and to prevent late resorption. Compared with the Müller ring, the Burch-Schneider APC is much more adapted to meet these requirements, particularly when the graft covers more than 50 p. 100 of the socket.

Acetabulum↗
PubMed2001

[Bilateral subtotal scapulectomy for chondrosarcoma in Ollier's disease within a 16-year interval].

PURPOSE OF THE STUDY: We report the case of a young man with Ollier's disease who underwent three successive procedures for sarcomatous degeneration of some of his endochondromatous lesions. From the age of twenty, the patient required surgery for resection of a cartilage tumor of the body of L5, amputation of the right index finger, and successive right then left subtotal scapulectomy. At 40 years, the patient presents other stable lesions, mainly located on the right side of the body. We were particularly interested in the functional outcome of the two shoulders in this patient who continues to have normal social and occupational activities.

Adult↗
PubMed2001

[Failure of acetabular cups fixed with cement and thick embedded wire mesh].

PURPOSE OF THE STUDY: We report our experience with the SKH(R) cemented acetabular cup, analyzing the clinical and radiographic consequences of using cement armed with a thick embedded wire mesh. MATERIAL AND METHODS: Between June 1990 and June 1991, 118 total hip arthroplasties (THAs) were performed in 110 patients (8 bilateral cases) using the SKH(R) cemented acetabular cup, a self-blocking cemented femoral stem with anterograde injection made of a Ti-6Al-7Nb alloy and a 28 mm ceramic polyethylene articulation. Mean follow-up for 97 implants (91 patients) was 7.1 years (3 - 9 years). Mean age at implantation was 65 years (36 - 85 years) (43 men and 48 women). THAs were performed for degenerative joint disease (n=79) including 67 cases of primary disease, necrosis (n=11), rheumatoid disease (n=6), and fracture of the femoral neck (n=1). RESULTS: For the 118 procedures, there were 4 complications: 2 dislocations (no revision), one failure of the ceramic head and one implant infection (with revision). As assessed by the Postel-Merle-d'Aubigné score as modified by Charnley for the mobility criterion, clinical outcome was excellent or good in 82% of the cases, fair in 11% and poor in 7%. According to the Massin criteria at last follow-up, there were 13 cup loosenings (13.4%, 10 migrations and 3 total lucent lines > 1 mm); revision procedures were performed in 6 cases. A lucent line postoperatively, observed in 51% of the cases (p=0.025) and involving all or part of zone 1 in 44% (p=0.047), was predictive of acetabular failure. Linear polyethylene wear as measured manually was 0.08 mm/year (average) for non-loosened cups and 0.2 mm/year for loosened cups; the difference was significant (p=0.001). On the contrary, the thickness of the cement, measured at the limits of the three De Lee and Charnley zones, cup tilt and size, age, weight and patient activity level had no effect on failure rate. Actuarial survival of the cup at 9 years was 86.3% taking aseptic loosening (with or without revision) as the failure criterion and 93.8% taking revision for aseptic loosening as the failure criterion. DISCUSSION: These results were rather disappointing. The thick layer of cement reinforced with the wire mesh produces a metal back effect with the known consequences in terms of loosening, cement-bone lucent line, and polyethylene wear. A modification is now undergoing thermal and mechanical assessment. A thinner and tighter mesh would appear to be preferable.

Acetabulum↗
PubMed2001

[Straight femoral taper in cementless primary total hip replacement in less than 65 year-old patients: multicenter study of 115 consecutive implantations at mean 8,2 year follow-up].

PURPOSE OF THE STUDY: The Swedish Arthroplasty Registry experience with cemented primary total hip arthroplasty (THA) has pointed out age below 65 and high activity level as 2 major factors impairing THA long-term outcome. The aim of this study was to provide intermediate results of cementless femoral replacement in primary THA with use of the Alloclassic-SL grit-blasted titanium stem in "high risk" groups of patients. MATERIAL AND METHODS: From June, 1988 to June, 1992, 127 cementless primary THA's were consecutively performed in<65 year old patients in 2 institutions. Acetabular components were all cementless (threaded cup in 74%) and bearing surfaces were all alumina-ceramic 28mm heads on polyethylene (PE). Five patients (6 hips) died and 6 other hips were lost to follow-up before the 5-year minimum follow-up. Thus, 115 hips in 106 patients could be fully reviewed after a 8.2 year average follow-up period (range, 5 to 12 years). Mean age at surgery of the 62 male and 44 female patients was 52 years (range, 27 to 65 years). RESULTS: Of the index group (127 hips), intra-operative fracture of the greater trochanter and early dislocation were noted in 4.7% and 3.2% of hips, respectively. Of the study group (115 hips), clinical results according to the Merle d'Aubigné and Charnley rating system were graded excellent and good in 94% of hips and fair in 6% (7 hips), with no poor result. Radiologically, early subsidence of more than 2mm could be detected in 8 hips (7%). Calcar atrophy and spot welds were noted in 81% and 89% of hips, respectively. Proximal reactive and lucent lines and mild proximal stress shielding were observed in 10.5% and 4.3% of hips, respectively. Ten-year survivorship with stem revision for any reason as the end point was 99.2% (92.4-99.9) (1 stem exchanged and reoriented for immediate dislocation). One revision is pending for extensive femoral osteolysis due to polyethylene (PE) wear. There was no stem fracture and no ceramic head breakage thus far. Overall PE-wear rate ranging 1-2 mm was detected in 13 hips (9.6%) and femoral osteolysis in 4 hips (3.5%). DISCUSSION: Mid-term results of this cementless straight taper at 10 year are at least equal to those of well performing cemented components, even in "high risk" groups of patients. Conversely, 28mm alumina-ceramic heads can reduce but not prevent the occurrence of PE-wear in such a healthy and active population. CONCLUSION: Press-fitting but not filling the femoral canal with rough titanium straight tapers like the Alloclassic-SL femoral component represent a promising alternative to modern femoral cementing technique in primary THA. Improvement is expected through the use of more wear resistant bearing surfaces.

Adult↗
PubMed2000

[Arthroscopic treatment of acetabular labrum lesions: a series of 12 patients with a 4-year follow-up].

PURPOSE OF THE STUDY: The aim of this work was to report our experience with arthroscopy for the treatment of acetabular labral lesions and identify prognostic factors determining mid- and long-term outcome. MATERIAL AND METHODS: Between August 1991 and December 1997, 12 patients (ten women, two men, mean age 39 years, age range 25-61 years) underwent arthroscopic treatment of an acetabular labrum lesion. All were reviewed at a mean 4 years follow-up (18 months-8 years). Half of the patients (n =6) had a history of hip surgery: two femoral osteotomies and one acetabular bone block for congenital hip dislocation, two high-energy traumas and one traumatic dislocation. Clinical manifestations including pain (n =12), a sensation of a snag (n =10), or blockage (n =8) had developed over a mean 15 months (2-24 months). Standard x-rays evidenced early signs of degenerative disease in four cases and acetabular dysplasia in four (5 degrees <VCE <18 degrees ), and were normal in four. Arthroscanography was performed in all cases and always evidenced a lesion of the anterior or anterosuperior part of the labrum, generally a fissuration (n =7). The surgical procedure performed on an orthopedic table with traction on the limb lasted 45 to 75 min for regularization of the degenerated labrum in three patients, resection of the languette in six, the anse de seau in two or the labral notch in one. A short hospitalization (24 to 48 hours) was sufficient with immediate weight bearing with two canes. One patient developed sciatic paresia which regressed in 72 hours with vulvar edema due to excessive peroperative traction. RESULTS: Besides the labral lesion, the exploration also identified an associated chondral lesion in seven cases (acetabulum in two, femoral head in three, both in two) which had been suspected in six cases from preoperative imaging (osteoarthrosis in four, dysplasia in two) and which affected the final outcome. Four of these patients (osteoarthritis in two and dysplasia in two) worsened clinically and radiographically to the point where a total hip arthroplasty was required in three. Among the three other patients, two had residual pain (osteoarthritis in one and initial x-ray normal in one) with no radiographic deterioration and only one (osteoarthrtis) was totally relieved without any radiographic deterioration at six years follow-up. Among the five patients with no chondral lesions, three (with normal x-rays initially) were pain free at four years follow-up while the two others (dysplasia) had residual pain at two years follow-up with no sign of osteoarthrtis on the latest x-rays. DISCUSSION: Lesions of the acetabular labrum are uncommon but can be treated arthroscopically. Resection of the labral lesion is immediately effective but does not prevent long-term degradation of the joint if there is an associated chondral lesion.

Acetabulum↗
PubMed1999

[Paraplegia secondary to surgery of the abdominal aorta].

We report the case of an 84 year-old man who suffered of paraplegia after surgery of an abdominal aortic aneurysm. The neurologic status did not improve during 5 years of follow-up. This complication is rare in light of the review of the literature. It is more frequent after emergency (1.4%) and redux (19%) surgery than after elective surgery (1.1%). Its mechanisms are anatomic (occlusion of the Adamkievitz artery and of the pelvic collateral arteries) and hemodynamic mechanisms (thromboembolism, low systemic tension, long supra-renal clamping). Since pre-operative aortography to detect anatomic variations is not realistic, its only prevention remains maintenance of intra-operative hemodynamic, systemic heparinization, and preservation of the pelvic collateral circulation.

Aged↗
PubMed1997

[Carotid endarterectomy by eversion and reimplantation. Techniques and results].

Endarterectomy of the carotid bifurcation through a longitudinal arteriotomy of the common and internal carotid arteries followed by a direct closure is still accepted as the main surgical technique for carotid stenoses. However, this technique is complicated in about 10% of the cases by a restenosis. Mechanisms of myointimal hyperplasia leading to restenosis are not completely explained. The technique of eversion endarterectomy of the internal carotid artery has been said to be an alternate technique which could decrease the incidence of restenosis. We described the three main techniques of eversion endarterectomy and their results. The technique of eversion endarterectomy after proximal section of the internal carotid artery is the most frequently used. It allows to treat easily length excess of the internal carotid artery. Its results are good in terms of neurologic morbidity and mortality. However, randomized comparative studies are still required in order to determine its role on the incidence of restenosis despite the first encouraging results of first non comparative studies. The technique of eversion endarterectomy after distal section of the internal carotid artery has been proposed by Chevalier who reported also good short term results and no delayed restenosis.

Carotid Artery, Internal↗
PubMedDate not supplied

Hip arthroscopy in hereditary multiple exostoses: A new perspective of treatment.

The cases of 2 children (9 and 11 years old) with hereditary multiple exostoses disease are presented. The lesions were located primarily in the acetabular fossa of the left hip and caused pain and limitation of range of motion. Hip arthroscopy was performed to remove the exostoses without damaging the articular surfaces and the Y cartilage. After the procedure, the pain disappeared and normal range of motion was recovered for both children. Conventional surgery would have required hip dislocation to access these lesions with an increased risk of femoral head necrosis. These cases constitute a new and interesting application of hip arthroscopy.

Acetabulum↗