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O Gagey

Publications and source records attributed to O Gagey.

At least 19 recordsLinked to original sources
PubMed2006

Radial head fracture in the medial collateral ligament deficient elbow; biomechanical comparison of fixation, replacement and excision in human cadavers.

A widely used clinical recommendation is that in the presence of medial collateral ligament injuries, two-part radial head fractures should be fixed rather than excising or replacing the radial head. Direct biomechanical data comparing fracture fixation, radial head replacement and excision in a human cadaveric elbow model, have not been previously described. Such comparison is clinically important as with the increasing availability of radial head implants and promising follow up results, the role of radial head replacement in fracture management may have to be redefined. In this study, five fresh cadaveric elbows had radial head fracture creation and medial collateral ligament division, fracture fixation, radial head replacement and excision. Valgus and varus laxity were determined using an electromagnetic tracking system. Radial head replacement leads to a similar valgus (P=0.80) [corrected] laxity as compared to radial head fixation. Radial head excision resulted in a significantly greater valgus laxity as compared to radial head fixation (P=0.02) or replacement (P=0.03). Both radial head excision and replacement led to a greater varus laxity as compared to fixation. Our results suggest that in the elbow with medial collateral ligament injury and two-part radial head fracture, fixation is overall biomechanically superior as compared to replacement and excision.

Aged↗
PubMed2006

Biomechanics of the deltoideus.

The objective of this study was to determine the direction of the migration engendered by the middle deltoideus on the upper end of the humerus. Eleven patients suffering from shoulder pathology underwent an MRI examination (3 mm thick slices). From these MRI slices, 3D reconstructions were obtained for each patient by using a manual data capture system (SliceOmatic((R))). From this geometry, a mechanical model of the deltoideus was produced, taking into account the contacts between the latter and the following anatomical parts: supraspinatus, infraspinatus and humeral head. For the 11 shoulders, we have obtained a deltoideus showing a global resultant oriented upwards. There was, however, a component oriented downwards (at the level of the humeral head), its intensity being 40-80% less than the component oriented upwards (at the level of the deltoideus V). It is important to note that this study is valid only in the initial degrees of lateral elevation. The deltoideus is an elevator muscle of the humeral head in the glenoid, presenting nevertheless a component oriented downwards. The deltoideus would, therefore, intervene to recenter the shoulder during an abduction movement.

Adult↗
PubMed2005

Influence of glenohumeral mismatch on bone strains and implant displacements in implanted glenoïds. An in vitro experimental study on cadaveric scapulae.

In shoulder arthroplasty, there is no consensus about the ideal mismatch between a prosthetic humeral head and a glenoïd component. Thus, investigations into mismatch effects from a biomechanical point of view can be useful. The aim of this in vitro study was to help us understand mismatch influence on bone strains, translational forces in the joint and implant/bone displacements in implanted scapulae. Five fresh cadaveric scapulae were implanted with a cemented keeled polyethylene implant. The lower part of the scapulae was embedded and the loadings were carried out using five metallic spheres simulating mismatches of 0, 2, 4, 5 and 6 mm. Loadings included a constant compressive preload of 392N and an anterior, posterior, inferior and superior translation of 2.5 mm. We measured the transversal force necessary to produce the imposed translation, the strains at six locations around the peripheral cortex of the glenoïd using strain gages and the relative implant/bone displacements using CCD cameras. Generally, the increase of mismatch reduced the translational forces, the strains around the glenoïd and, except for the anterior loading, the relative implant/bone displacements. Few and even no significant differences were observed when the mismatch varied from 0 to 2 mm; the number of significant differences increased when the mismatch varied from 0 to 4mm and from 0 to 5 mm; the results obtained for a 0-6 mm variation in mismatch were comparable to those obtained for a 0-5 mm variation. This study underlines that the mismatch has a significant effect on bone strains, relative implant/bone displacements and induced translational forces when a compressive preload and imposed translations were applied on implanted scapulae.

Aged↗
PubMed2005

Neurovascular relationships of the approaches for arthroscopic total trapeziectomy with ligamentous stabilization.

The aim of this study was to define the neurovascular relationships of the approaches used during arthroscopic total trapeziectomy with the Thompson "suspension-plasty." Fifteen fresh cadavers in which trapezio-metacarpal arthritis had been confirmed by preoperative radiographs were chosen. There were 12 women and 3 men (average age: 87 years), and small joint arthroscopy equipment was used. Two approaches for the trapezio-metacarpal joint were used: an ulnar approach situated at the ulnar border of the extensor pollicis brevis tendon and a radial approach placed at the middle of a line joining the tendons of the flexor carpi radialis and the abductor pollicis longus. A new transosseous approach at the base of the first metacarpal ("trans-M1" approach) is suggested and was used to do the ligamento-plasty. After the operation, a large skin flap was elevated in order to measure the distance between each surgical approach and the different neurovascular structures (radial artery, dividing branches of the superficial branch of the radial nerve and the end of the lateral cutaneous nerve of the forearm) and to verify the absence of neurovascular lesions. The different neurovascular structures at risk during this arthroscopic maneuver were the radial artery for the ulnar approach, the branches of the superficial branch of the radial nerve for all of the approaches and the ending of the lateral cutaneous nerve of the forearm for the radial and "trans-M1" approaches. The use of the approaches described allows arthroscopic trapeziectomy with the Thompson suspension-plasty without us having noted neurovascular lesion.

Aged, 80 and over↗
PubMed2005

Significance of the latissimus dorsi for shoulder instability. II. Its influence on dislocation behavior in a sequential cutting protocol of the glenohumeral capsule.

In a cadaveric instability model that leaves all muscles intact initially, the latissimus dorsi seemed to play a role when complete section of the glenohumeral capsuloligamentous structures did not result in a locked anteroinferior dislocation. The present study was carried out to determine whether the latissimus dorsi does truly affect dislocation in a modified cutting protocol, and to find an anatomic explanation for this apparent behavior. This article (Part II) details the results of a sequential cutting study and relates these results with the anatomic findings of Part I. In 75 shoulders, the influence of the latissimus dorsi on dislocation behavior in the apprehension position after section of all capsuloligamentous structures was examined. After cutting all capsuloligamentous structures, either on the glenoid or on the humeral side, the tendon of either the latissimus dorsi or the subscapularis was cut. Capsular lesions on the glenoid side (20 shoulders) resulted in a locked dislocation in 16 specimens. In the other four shoulders, there was a metastable dislocation after cutting the entire capsule, which did not change after cutting either tendon. With lesions on the humeral side (55 shoulders), three possibilities arose: metastable (17 shoulders), locked anterior (9 shoulders) or locked anteroinferior (29 shoulders) dislocation. This difference in dislocation behavior was related to the variability of the tendon-cartilage distance (TCD) and the type of scapular connection of the latissimus dorsi. A locked anteroinferior dislocation was always observed when the TCD was more than 20 mm, regardless of the type of scapular connection. With a TCD < 20 mm, a metastable dislocation was the result when there was a type 1 scapular connection and a locked anterior dislocation was seen when there was a type 2 scapular connection. The tendon of the latissimus dorsi can restrain the humeral head from dropping inferiorly or can lead to a spontaneous reduction of a dislocation, depending on its anatomy. This effect can only take place in the infrequent situation of humeral avulsion of the glenohumeral ligaments. This may be an explanation for the relative paucity of these lesions in clinical instability series.

Aged↗
PubMed2005

Significance of the latissimus dorsi for shoulder instability. I. Variations in its anatomy around the humerus and scapula.

In a cadaveric instability model that leaves all muscles intact initially, we studied anteroinferior glenohumeral dislocation behavior after section of the ligaments on the humeral side of the joint. In this study, the latissimus dorsi seemed to play a role when complete section did not result in a locked anteroinferior dislocation. We therefore initiated a study to test the hypothesis that the latissimus dorsi may, in certain circumstances, depending on variations in its anatomy, influence dislocation behavior. Here, in Part I, we present the results of the anatomic study of latissimus dorsi and its tendons. The anatomy of the latissimus dorsi pertaining to the scapula and humerus was studied in 100 cadaver specimens. The distance between the uppermost part of the tendon of both the latissimus dorsi and the teres major and the edge of the articular cartilage of the humeral head (tendon-cartilage distance, TCD) as well as the width and length of the tendons were measured. Furthermore, the relationship between latissimus dorsi and the inferior angle of the scapula was studied. The tendon of the latissimus dorsi inserted at a variable distance from the cartilage of the humeral head: the TCD ranged from 12.6 to 31.6 mm (mean 21.06 mm+/-5.11 mm). The latissimus dorsi can have muscular fibers arising from the inferior angle of the scapula (type 1 scapular connection, 43%). Alternatively, there may be only a few fibrous strands between the muscle and the scapula or there may be an intervening bursa (type 2 scapular connection, 57%). This variability in the morphology of the latissimus dorsi may be a factor explaining the differences observed in a study of humerus-based sequential cutting of the glenohumeral capsule. This possibility is explored in Part II of the study. The latissimus dorsi may also complete the tendinous protection of the humeral side of the capsule generally provided by the rotator cuff.

Cadaver↗
PubMed2004

Quantitation of ligament laxity in anterior shoulder instability: an experimental cadaver model.

Three groups of cadaver specimens were studied. In group 1 (20 shoulders) glenohumeral ligaments were detached from the humerus until a permanent dislocation of the humeral head occurred in abduction plus external rotation. On the dislocated joint the ligament was reconstructed using a fascia lata lengthening plasty. After the plasty had been completed, the shoulder was reduced and instability checked in the same position. Then the capsule (including the plasty) was harvested and measured. In group 2 (20 shoulders), after the plasty had been completed in the same conditions as above, the capsule was progressively reduced by 2 mm steps until the instability disappeared. Then the capsule (including the plasty) was harvested and measured. In group 3 (12 shoulders), measurements of the head and of the capsule were done. To dislocate the shoulder the section of the three glenohumeral ligaments was required. Lengthening of the capsule in group 1 was 240-250%. In all cases shortening of the capsule led to the stabilization of the shoulder. After stabilization of the shoulder was reached a residual lengthening of 175-185% was recorded. In 3 out of 4 shoulders the amount of capsule shortening required to return to a stable shoulder was between 16 and 18 mm. This experiment did not reproduce the Bankart lesion; therefore it only concerns atraumatic instability. The main limitation of this model is the low lever force that may be used to dislocate the shoulder; consequently the elasticity of the glenohumeral ligament was not taken in account. The experimental values were likely over-estimated. Nevertheless the present results provide useful information for building an experimental model of atraumatic instability of the shoulder.

Aged↗
PubMed2002

[Contribution of systematic culture of drainage fluids in Altemeier class 1 and 2 procedures].

PURPOSE OF THE STUDY: We conducted a prospective study to determine the therapeutic impact of systematic culture of suction drainage collections in Altemeier class I and II procedures. MATERIALS AND METHODS: We examined the following questions: how many microbiologically positive samples and infections of the operative site were present in the included patients? for positive cases, what was the antibiotic prescription (excluding antibiotic prophylaxy protocols planned before surgery for cleaning)? if the sample was positive in a patient with no clinical infection, what antibiotics were prescribed? RESULTS: A total of 1039 samples were collected in 470 patients undergoing Altemeier class I and II procedures. One hundred five cultures were positive in 34 patients who had undergone major surgery. There were 11 postoperative infections during the study period. Mean delay to diagnosis of infection was 19.5 days. Only one infected patient with positive drainage samples developed an infection on the 7(th) day; the causal germ was different from that identified in the drainage collection. Only one of the patients with a positive drainage sample was given antibiotics, but this treatment was initiated at peroperative reception of the laboratory results. DISCUSSION: Our findings demonstrate that systematic samples of drainage collections make no contribution to therapeutic decision making in patients undergoing class I and II surgery.

Bacteria↗
PubMed2001

The fibrous frame of the deltoid muscle. Its functional and surgical relevance.

Black lines seen on magnetic resonance imaging in the middle part of the deltoid suggest the presence of fibrous bands. Anatomic study of 30 deltoid muscles was done. Eight half-cone shaped distal fibrous structures merged together into the distal tendon of the deltoid muscle. The middle part of the deltoid muscle contains four deep fibrous bands that glide inside the distal half-cones. The anterior and posterior parts of the deltoid muscle lacked such bands. Histologic study confirmed the presence of the bands and cones. In the middle part of the deltoid, muscle fibers are oblique between the bands or between the bands and the half-cones. This multipennate structure favors strength instead of range of excursion of the muscle. Because of its significant change of direction around the humeral head, at the onset of elevation of the arm, the deltoid muscle sustains forces that press the muscle against the head which then leads to deformation of the muscle. The fibrous bands make the muscle strong enough to support these forces. The middle part of the muscle is of greatest importance in comparison with the other parts. This should be considered during shoulder rehabilitation. The presence of the fibrous band originating from the anterior corner of the acromion may help create a strong repair after splitting the deltoid.

Aged↗
PubMed2001

[Revision arthroplasty of the shoulder for painful glenoid loosening: a series of 14 cases with acromial prostheses reviewed at four year follow up].

PURPOSE OF THE STUDY: We present the results of a continuous series of 14 patients who underwent revision arthroplasty of the shoulder for painful major loosening of the glenoid component. MATERIAL AND METHODS: Mean follow-up was four years after revision. Loosening was diagnosed seven and a half years after the primary arthroplasty. The diagnosis of loosening was based on the association of a painful impairment of the shoulder with increasing radiolucency or migration of the component. The degree of pain alone guided the surgical decision. The posterior approach provided wide exposure. A glenoid component with an acromial fixation was used in all cases. RESULTS: The loosening was confirmed in all cases at surgery. Two were early failures of the fixation. The glenoid required a bone graft in all cases. The acromion was a useful landmark for proper positioning of the prosthesis. Fixation with cement and screws provided a strong fixation allowing immediate rehabilitation exercises. Good fixation of the glenoid component was achieved in all cases. After seven years follow-up there has been evidence of iterative loosening in one patient. In another case, one screw broke, suggesting forthcoming loosening. Twelve cases had no or very little pain. Two painful cases were associated with anterior migration of the humeral head. DISCUSSION: Even when the local conditions are unfavorable, good implant fixation can be achieved by grafting the glenoid bone loss. Functional improvement is essentially due to pain relief. CONCLUSION: This series, the largest published to date on revision surgery of painful loosening of total shoulder arthroplasty, demonstrated that iterative fixation is technically possible and can provide highly significant pain relief.

Adult↗
PubMed2001

[The fibrous frame of the rotator cuff. Contributions of an in vivo three dimensional study of the tendons of the rotator cuff].

The presence of a fibrous frame within the rotator cuff has been recently emphasized. This frame may be of interest in understanding of shoulder physiology and in attempts to improve shoulders disorders treatments. We report an original method to study the fibrous frame. MRI were done in healthy volunteers. 3D reconstruction were obtained and provided a 3D image of the fibrous frame. This technic should allow to calculate, for instance, the angles between the cuff muscles and the upper end of the humerus.

Humans↗
PubMed2001

[Pelvic and spinal giant metastases from thyroid carcinomas: report of 8 cases].

PURPOSE OF THE STUDY: We report 8 cases of giant metastases in 7 patients with a pelvis or spinal localization in patients with differentiated carcinoma of the thyroid gland. MATERIAL AND METHOD: Surgery was indicated for major functional disorders: pathological fracture, neurological complications. All patients were treated by embolization, tumor resection and reconstruction. All patients were given suppressive doses of thyroid hormones and 6 received complementary radiotherapy. Radioactive iodine, 100 mCu was also given in 5 cases. Outcome was analyzed retrospectively. RESULTS: Two postoperative infections were successfully treated by surgical cleaning in one operation. There were no surgery-related neurological complications. One patient died in the immediate postoperative period due to the cancer. Mean follow-up in the other patients was 4 years. Functional outcome was excellent without local recurrence or mechanical complications. DISCUSSION: These results suggest that surgical resection of giant bone metastases from thyroid carcinomas can provide favorable functional outcome similar to that achieved for small-sized metastases.

Adenocarcinoma, Follicular↗
PubMed2000

Mechanics of the deltoid muscle. A new approach.

The Inman concept of the mechanics of the deltoid describes a vertical upward oriented traction exerted on the upper end of the humerus at the beginning of arm elevation. However, Duchenne de Boulogne showed that the middle deltoid pushes the head downward. When the arm is at rest, the trajectory of the middle deltoid fibers changes by more than 90 degrees so that the humeral head is enveloped by the muscle; this suggests that the deltoid acts on the humeral head like a cable on a pulley. The authors studied the area of contact between the deltoid and the humeral head in three-dimensional reconstructed shoulders. A new model, which includes the pulley effect, was designed to explore the resultant total force applied by the deltoid onto the humerus. In most cases the resultant vertical force was oriented downward. Thus, the conventional model is not complete. The current model indicates that the deltoid prevents upward migration of the humeral head and compresses it against the glenoid. This explains why many shoulders function well despite a massive cuff tear. This also implies that reeducation of the deltoid is a major aspect of the rehabilitation for patients with a rotator cuff tear.

Biomechanical Phenomena↗
PubMed2000

[Surgical treatment of metastases from thyroid cancer in the axial skeleton. A retrospective study of 18 cases].

Between 1990 and 1997, 18 patients with a mean age of 55.5 years (11 females, 7 males) underwent surgical treatment for a metastasis from thyroid cancer involving the axial skeleton. At the time of surgery all patients had a poor prognosis: 7 metastases revealed the thyroid cancer, all 18 patients had a neurological or mechanical complication, 9 had multiple metastases, all were over 40 years of age. After arteriography with embolization, the surgical procedure consisted of curettage of the tumor and reconstruction, followed by treatment with iodine 131. The survival rate 3 years after surgery was 50%. At the last review, the functional outcome was good and 17 patients had total neurological recovery. Four complications occurred: 1 operative hemorrhage, 3 postoperative infections. Four patients had local recurrence of the metastasis with a one-year survival rate of 20%. When the thyroid cancer was revealed by the axial metastasis, the 3-year-survival rate was 42%. In cases with huge metastases, the 3-year-survival rate was 71%. It appears from these data that surgical treatment of metastases from thyroid cancer in the axial skeleton still achieves a good functional outcome even in cases where neurological or mechanical complications had occurred before surgery.

Adult↗
PubMed1999

Epidemiology of bacterial infection during management of open leg fractures.

In a randomised double-blind trial conducted between 1990 and 1994, 616 patients from 43 centres, pefloxacin (group P, 316 patients) and a cefazolin-oxacillin combination (group C, 300 patients) were compared in the prophylaxis of bone infection after grade 1 and 2 open leg fractures. Samples were obtained at emergency, before and during surgery, and from drain aspirates. Antimicrobial susceptibility, slime production and adherence properties of the bacteria were tested. Cultures at emergency and before surgery showed similar distributions of gram-positive and gram-negative bacteria in both groups, while wound closure and infecting isolates showed prevailing gram-positive bacteria in group P and gram-negative bacteria in group C. Positive cultures at each stage were correlated with the occurrence of infection but were not predictive of the infecting species, which were nosocomial bacteria in most cases. Positive cultures at wound closure warn of a higher infection risk. Twenty-one of 316 (6.6%) patients in group P and 24 of 300 (8%) in group C were considered infected within 3 months. The difference is not significant (chi-square test = 0.42; P = 0.51). Infecting strains were isolated from 38 patients (group P, 18; group C, 20). Infecting species, although not predictable, appear to be those escaping the spectrum of the prescribed antimicrobial prophylaxis.

4-Quinolones↗
PubMed1999

[Vascularization of the trochanter fragment after digastric trochanterotomy in man].

We examined the human vascular anatomy to the greater trochanter after digastric trochanterotomy, using some injection techniques and practiced the trochanterotomy (digastric, classic). We found 3 major sources of blood supply to the greater trochanter: the proximal soft tissues, including the gluteus medius and minimus, were mainly vascularized from the internal iliac artery system, and the distal soft tissues, including the vastus lateralis, were vascularized from the branches of the lateral circumflex femoral artery (LCFA). A third possible source of blood circulation came from the LCFA, but this branch was only found in 12 to 15 samples. Many vascular structures from the LCFA were concentrated in the anterior half of the vastus lateralis muscle which were deeply imbedded and ran upward to the trochanteric insertion of the vastus lateralis muscle. The distance from the superior tip of the greater trochanter to the point at which the first branch of the descending branch of the LCFA enters into the vastus lateralis muscles was from 65 mm. to 125 mm. The descending branch was found consistently in all 20 samples. Our results proved that with digastric trochanterotomy, we can preserve all three sources of vascularization whereas with classic trochanterotomy the supply from the transverse and descending branches of the LCFA are lost.

Femoral Artery↗