Christophe Chantelot

Variations of pelvic anteversion in the lying and standing positions: analysis of 24 control subjects and implications for CT measurement of position of a prosthetic cup.

The position of the acetabular implant plays a dominant role in the displacement of a total hip prosthesis. CT allows precise measurement of the position of the cup, but the influence of pelvic rotation on this measurement is unknown. The aim of this study was to determine, in a group of healthy subjects, whether a pelvic equilibrium exists specific to each individual, and whether this is constant over time on the one hand and between the standing and lying positions on the other. The study concerned 15 men and 9 women with a mean age of 31 years. Each subject had strictly lateral radiographs of the pelvis, lying and standing, repeated at two different times. Pelvic version was measured in these radiographs. Each individual had a pelvic position constant over time, both in the lying and standing positions, However, there were important variations of the position of the pelvis during passage from the lying to the standing position 22 patients had retroversion of the pelvis by a mean of 7° (2-18°) and 2 others had an anteversion of 3°. These major variations of the pelvic position between the standing and lying positions explain why CT studies made in the lying position do not allow for the anteversion of the cup in the standing position, which is close to the dynamic situation during which displacement may occur. Thus, an excessive anteversion of the cup may be masked when the scan is made in the lying position, since in this position the anteversion of the pelvis leads to retroversion of the cup. The error may reach 20°, so that we recommend that CT measurements made without allowing for the position of the pelvis should be interpreted with caution.

Inter- and intraobserver reproducibility in radiographic diagnosis and classification of femoral trochlear dysplasia

Dejour’s radiographic criteria are commonly used to diagnose and assess femoral trochlear dysplasia in case of patello-femoral instability. The aim of this study was to establish the intra- and interobserver reliability of these radiographic criteria. Sixty-eight lateral knee radiographs were examined independently by 7 observers (2 juniors, 5 seniors) to assess interobserver agreement, and the 2 juniors repeated the observations to test intraobserver agreement. These 68 true lateral views were harvested from clinical records of 64 patients who underwent a trochleoplasty because of patellofemoral instability. To evaluate the agreement on analytic data (morphologic type of trochlea) we used the kappa statistical method, and to evaluate the agreement on numerical data (depth and prominence of the trochlear groove) we used interclass correlation analysis. The “crossing sign” (between the trochear groove and the anterior aspect of both condyles) was reliable since the probability of rating as normal a pathologic trochlea was only 3.1% (0 to 8.8%). In classifying trochlear morphology interobserver agreement was slight (kappa = 0.17) and intraobserver agreement was fair (kappa = 0.3). On the other hand, the measurements of the depth and prominence of the trochlear groove were more reliable since the interclass coefficients between observers were 0.62 and 0.38 respectively. The most frequent interobserver error was related to misdiagnosis of type II. To clarify Dejour’s criteria we propose a diagnosis of type II only when 5 mm or more are measured betweeen the intersections with the medial and lateral femoral condyles. We recommand the use of the prominence of the trochlear groove to evaluate the grade of bony trochlear dysplasia.

Long-term Survivorship of Hip Shelf Arthroplasty and Chiari Osteotomy in Adults

The current authors retrospectively assessed 56 hip shelf arthroplasties (48 patients) with a mean followup of 17 years (range, 15–30 years) and 89 Chiari osteotomies (82 patients) with a mean followup of 13 years (range, 6–25 years) done in adults with painful hip dysplasia. Preoperative joint space narrowing was observed in 32 of 56 shelf arthroplasties and in 67 of 89 Chiari osteotomies. Survival rates, using hip replacement as the end point, were 37′ (20′ to 54′) at 20 years for shelf arthroplasty and 68′ (54′ to 81′) at 18 years for Chiari osteotomy. The severity of preoperative arthrosis was the main factor that impaired the survivorship of shelf arthroplasty and Chiari osteotomy. With arthritic changes without joint space narrowing, the 18-year survival rates were 83′ (69′ to 97′) for shelf arthroplasty and 94′ (89′ to 99′) for Chiari osteotomy. Shelf arthroplasty is best indicated for moderate dysplasia (center edge angle >0°) without severe arthrosis. Chiari osteotomy is best suited for severe dysplasia (center edge angle <0°) especially without or with slight arthrosis. Chiari osteotomy also can be a salvage procedure when marked joint space narrowing is present but only if it is related to severe dysplasia (center edge angle <0°).

Second generation Guepar total arthroplasty of the thumb basal joint: 50 months follow-up in 84 cases

BACKGROUND Osteoarthritis of the thumb basal joint is the most common location for hand degenerative joint disease. First, carpometacarpal (CMC) joint arthroplasty is one treatment option. The purpose of this article is to present the outcome of the GUEPAR II prosthesis, a total trapeziometacarpal cemented implant of the retaining ball-and-socket design type. Numerous other advantageous features of this implant, second generation of an earlier version are explored. HYPOTHESIS Clinical and radiological results confirm the GUEPAR II trapeziometacarpal arthroplasty as a reliable and efficient evolution of earlier prosthetic designs. MATERIALS AND METHODS Eighty-four GUEPAR II prostheses were implanted to treat advanced and severely incapacitating first CMC osteoarthritis. The average follow-up time in this collaborative series (from 2 centers) was 50 months. RESULTS There were no intraoperative complications and no dislocations at the final follow-up evaluation, 92% of patients were satisfied or very satisfied with their results with objective improvement of their Kapandji score. Strength was closely comparable to the nonaffected side. Radiographic studies at the final follow-up evaluations did not show (except in one socket revision instance) signs of implant loosening. On occasion, non-progressive radiolucent lines were observed. More than 80% of the patients remained pain free. CONCLUSIONS In our series, GUEPAR II total joint arthroplasty of the thumb CMC joint has proven to be efficacious, improving motion, strength, and achieving a high degree of pain relief. Successful outcome appears in our experience contingent upon strict compliance with numerous surgical technique details. Current research focuses on improving bipolar fixation by developing press-fit cementless implants.

Innervation of the medial epicondylar muscles: an anatomic study in 50 cases

The median nerve is classically distributed to the medial epicondylar muscles by two branches (superior and inferior) for the pronator teres muscle, a common trunk for the flexor carpi radialis and palmaris longus muscles, and a branch for the flexor digitorum superficialis muscle. The 50 dissections were made by two workers on 30 upper limbs of formolized cadavers and 20 limbs from fresh-frozen cadavers. The innervation of the pronator teres m. was classical in only 26% of cases, and the “normal” pattern for the flexor carpi radialis and palmaris longus mm. was found in only 40% of cases. The innervation of the flexor digitorum superficialis m. was the least subject to variations, a single branch being observed in 68% of cases. We found a solitary medio-ulnar anastomosis of Martin-Gruber to the flexor carpi ulnaris muscle. This study confirmed the great variability of the branches of the median nerve at the elbow, and the importance of identifying them in surgical procedures for transposition of the medial epicondyle.

Résection de la rangée proximale des os du carpe: Résultats de 25 cas au recul moyen de 30 mois

Resume La resection de la rangee proximale des os du carpe consiste en une simplification de l’articulation radio-carpienne, et est principalement realisee dans le cadre de collapsus carpien avance. L’emergence de nombreuses alternatives therapeutiques justifie une etude de ses resultats, afin de mieux preciser ses indications au sein des differentes pathologies concernees. Une evaluation clinique et radiologique a ete effectuee chez 25 patients, ayant beneficie de cette intervention entre janvier 1999 et fevrier 2004, au recul moyen de 30 mois. Trois etiologies principales etaient representees : sequelles de fracture du scaphoide (9 cas), sequelles de dissociation scapho-lunaire (9 cas) et maladie de Kienbock (6 cas). Tous les patients ont ete operes par voie d’abord posterieure et ont fait l’objet d’une analyse evaluant le resultat clinique (douleur, force, mobilite), le resultat radiographique (hauteur du carpe, espace radio-capital), l’appreciation personnelle et une eventuelle reprise d’activite professionnelle. Les scores de Cooney et Culp ont ete calcules. L’arc de mobilite moyen en flexion-extension etait de 60° ; la force de la poigne etait mesuree, en moyenne, a 65 % de la valeur du cote oppose. Les douleurs ont ete ameliorees dans 88 % des cas et la note subjective moyenne etait de 15,2. Les scores moyens de Cooney et de Culp etaient respectivement de 58,0 et 67,8. Une perte de hauteur de l’interligne neo-articulaire, ne correspondait pas toujours a un mauvais resultat clinique. Les resultats des scores des patients atteints de maladie de Kienbock etaient inferieurs a ceux des cas post-traumatiques, sans qu’une difference statistique significative n’ait pu etre mise en evidence.PURPOSE OF THE STUDY Resection of the proximal row of the carpus which simplifies the radiocarpal joint is mainly performed for advanced collapse. With the development of several therapeutic alternatives, further study of outcome is warranted to better identify indications. MATERIAL AND METHODS Twenty-five patients who underwent proximal row carpectomy between January 1999 and February 2004 were reviewed clinically and radiologically at 30 months mean follow-up. Three main etiologies were noted: scaphoid fracture (n=9), scapholunate dissociation (n=9), Kienböck disease (n=6). A posterior approach was used for all patients. Outcome was assessed clinically (pain, force, mobility), radiologically (carpal height, radiocapital space), and subjectively by the patient. Resumption of occupational activity was noted as were the Cooney and Culp scores. RESULTS Average flexion-extension was 60 degrees . Average wrist force was 65% of the healthy side. Pain improved in 88% of wrists and the mean subjective score was 15.2. The mean Cooney and Culp scores were 58 and 67.8 respectively. A reduction in the height of the new articular space was not correlated with less favorable clinical outcome. Outcome in patients with Kienböck disease were less favorable than in trauma patients but the difference did not reach significance. DISCUSSION First row carpectomy is a paliative procedure which should only be performed when conservative treatment is no longer a valid option. Indications should be limited to Watson grade II, before cartilaginous damage affects the head of the capitatum. New techniques such as fusion-shortening, theoretically similar to resection, can now be used for advances collapse. We prefer resection over four-bone arthrodesis because of the lower risk of complications. In Kienböck disease, first row carpectomy should only be used for selected patients (Lichtmann III) due to the risk of early degeneration of the capitatum and radius heads.

Tolerance of Upper Extremity Pneumatic Tourniquets and their Effect on Grip Strength

This study was undertaken to evaluate tourniquet tolerance in healthy people. An arm tourniquet was inflated to 100 mmHg above systolic blood pressure for 21 minutes. We measured pain and grip strength before, during and at various times after deflation. We tested 40 subjects (20 women and 20 men) with an average age of 38 (range 22–58) years. Eight individuals did not tolerate the tourniquet for this length of time and the test was stopped. Visual analogical scale had a globally linear increase during tourniquet application. We noted a sensation of well-being just after deflation, quickly replaced by pain in the tested limb due to limb reperfusion. We also noted a significant loss of strength in the tested limb, which completely recovered by 48 hours. We also observed a significant loss of strength in the contralateral hand, which also recovered by 48 hours. The possible reasons for these temporary losses of strength in both the ipsilateral and contralateral limbs are discussed.

The abductor pollicis longus: relation between innervation, muscle bellies and number of tendinous slips

The aim of this study was to assess the relation between the insertions of the distal tendinous slips, the muscle bellies and the innervation pattern of the abductor pollicis longus (APL) muscle and of the extensor pollicis brevis (EPB). The upper extremities of 31 frozen cadavers were dissected under magnifying lenses to describe the distribution of the posterior interosseous nerve (PION). The number and the distribution of distal tendinous slip insertions of the APL muscle were variable. Two superficial and deep distal tendon groups were noted. The separation into superficial and deep muscular parts of the APL was frequent (87%). The EPB muscle was generally constituted by one muscle belly and one tendinous slip (93.5%). The innervation by the PION to the APL and EPB muscles was classified into five types. The specific innervation between superficial and deep muscular parts of the APL muscle, the specific innervation of the deep muscle bellies and the independence of the superficial and deep distal tendon groups of the APL muscle are arguments in favor of a complex functional role of the APL motor unit in thumb mechanics. However, no independence of the tendinous slips in the two distal tendon groups and no correlation between the number of tendinous slips and muscle bellies or innervation were observed. These limit the functional role of the two independent superficial and deep musculotendinous APL motor units. The use of the APL tendon for interposition arthroplasty, for tendon transfer or tendon translocation seems logical, particularly if using one of the two distal tendon groups.

Imaging of Sports-related Hand and Wrist Injuries: Sports Imaging Series

Hand and wrist injuries are common occurrences in amateur and professional sports and many of them are sport-specific. These can be divided into two categories: traumatic injuries and overuse injuries. The aim of this article is to review the most common hand and wrist sports-related lesions. Acute wrist injuries are predominantly bone fractures, such as those of the scaphoid, hamate hook, and ulnar styloid. Ligament lesions are more challenging for radiologists and may lead to carpal instability if undiagnosed. Overuse wrist injuries are mainly represented by tendinous disorders, with De Quervain syndrome and extensor carpi ulnaris tendon disorders being the most common among them; however, there are other possible disorders such as impaction syndromes, stress fractures, and neurovascular lesions. Finally, finger lesions, including closed-tendon injuries (mallet and boutonniere injuries, jersey finger, and boxers knuckle), flexor pulley injuries, and skiers thumb, should also be detected. (©) RSNA, 2016 Online supplemental material is available for this article.

Résultats à long terme des greffes cortico-spongieuses non vascularisées pour pseudarthrose du scaphoïde carpien: Cinquante-huit cas revus au recul moyen de 8,8 ans

Resume Le but de cette etude retrospective etait d’analyser les resultats obtenus dans 58 pseudarthroses du scaphoide carpien ayant beneficie d’une greffe cortico-spongieuse non vascularisee, afin de preciser les facteurs influencant les resultats et d’en determiner les indications ideales et les limites. Entre 1984 et 1999, 103 patients ont beneficie d’une greffe cortico-spongieuse non vascularisee, seulement 57 (58 poignets) ont ete revus (4 decedes, 30 ayant refuse de se deplacer en raison de l’eloignement geographique et 12 perdus de vue). Le recul moyen etait de 106 mois (19 - 212). L’âge moyen etait de 36 ans (20 - 62). Pour 45 patients, la fracture n’avait pas ete initialement diagnostiquee et le delai moyen du diagnostic etait de 35 mois (6 - 252). Dans la classification de Schernberg, la fracture etait situee : 11 fois en zone II, 40 fois en zone III et 7 fois en zone IV. Selon la classification d’Alnot, les stades de pseudarthrose se repartissaient en : stade I (13), stade IIA (20), stade IIB (22), stade IIIA (2) et stade IIIB (1). L’immobilisation apres l’intervention a ete en moyenne de 2,7 mois. La consolidation a ete obtenue dans 47 cas, en moyenne, au bout de 3 mois. Trente-six patients etaient tres satisfaits, 18 satisfaits et 4 non satisfaits. Vingt-sept patients ont presente des douleurs importantes sur la prise de greffe, mais celles-ci ont disparu en quelques mois et tous les patients ne gardaient au recul aucune sequelle. Par rapport au poignet sain, les amplitudes de mobilite etaient reduites pour la flexion (en moyenne de 8,7°), l’extension (en moyenne de 12,8°) et l’inclinaison radiale (en moyenne de 10,5°). Les autres secteurs de mobilite du poignet etaient respectes (en particulier la supination et la pronation). L’indice de hauteur du carpe etait en moyenne de 0,54 (0,47 - 0,57), et 9 poignets avaient une hauteur diminuee. L’angle radio-lunaire etait en moyenne de 4,8° (-17, + 27). Vingt poignets avaient une deformation en DISI. 36 patients ne presentaient pas ou peu d’arthrose. Onze pseudarthroses n’ont pu etre consolidees ; 7 d’entre elles presentaient au depart une necrose du pole proximal. Tous les patients ont ete ameliores pour la douleur. La survenue de l’arthrose etait favorisee par la persistance d’une deformation en DISI. Si cette technique autorise 81 % de consolidation, elle est depassee pour les stades arthrosiques evolues. La correction d’une deformation intra-carpienne en DISI apparait indispensable pour prevenir la survenue de l’arthrose. Cette technique ne doit pas etre proposee en cas de necrose du pole proximal, et il faut sans doute lui preferer un greffon vascularise.PURPOSE OF THE STUDY We conducted this retrospective study to analyze outcome obtained in 58 cases of carpal scaphoid nonunion treated with a non-vascularized corticocancellous graft. Our objective was to search for factors influencing outcome and identify appropriate indications. MATERIAL AND METHODS Between 1984 and 1999, 103 patients were treated with a non-vascularized corticocancellous graft. Fifty-seven patients (58 wrists) were retained for analysis (4 deaths, 30 not attending follow-up consultation far from their residence, and 12 lost to follow-up). Mean follow-up was 106 months (range 19-212). Mean age was 36 years (20-62). Mean time to diagnosis of fracture was 35 months (6-252); the fracture was not recognized initially in 45 patients. According to the Schernberg classification, fractures were localized in zone II (n = 11), zone III (n = 40), and zone IV (n = 7). Using the Alnot classification, nonunion was grade I (n = 13), grade IIA (n = 20), grade IIB (n = 22), grade IIIA (n = 2), and grade IIIB (n = 1). Mean immobilization after grafting was 2.7 months. RESULTS At three months, bone healing was achieved in 42 wrists. Thirty-six patients were very satisfied, 18 satisfied and four not satisfied. Twenty-seven patients presented significant pain at the graft harvesting site which regressed in all. There were no harvesting sequelae. Compared with the healthy wrist, we noted reduced flexion (8.7 degrees on average), extension (12.8 degrees on average), and radial inclination (10.5 degrees on average). Other wrist motions were not affected, particularly pronation and supination. The index of carpal height was 0.54 on average (range 0.47-0.57); carpal height was diminished in nine wrists. The radiolunate angle was 4.8 degrees on average (-17 degrees to +27 degrees). Dorsal intercalated segmental instability (DISI) was noted in twenty wrists. Bone healing was not achieved in eleven wrists, seven of which presented initial necrosis of the proximal pole. Pain improved in all patients. Persistence of DISI favored osteoarthritic degeneration. DISCUSSION With this technique, we achieved bone healing in 81% of the cases. Non-vascularized grafting cannot provide cure in the event of advanced osteoarthrtic degeneration. Correction of DISI appears to be an indispensable element for the prevention of osteoarthritis. This technique should not be proposed for patients with a necrotic proximal pole, a vascularized graft would be preferable.