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P Mertl

Publications and source records attributed to P Mertl.

At least 19 recordsLinked to original sources
PubMed2005

Relationship between ultrastructure and biomechanical properties of the knee meniscus.

The purpose of this study was to determine the biomechanical properties of the knee meniscus and to relate them to its ultrastructure. The knee joint menisci are semicircular, fibrocartilaginous structures interposed between the femoral and tibial condyles. For a long time, they were considered to be embryologic vestiges. This study describes the response of the knee joint meniscus to circumferential, radial and axial compressive forces. The results show an anisotropic response of the knee joint meniscus to unconfined compression. The Young's modulus increased approximately twofold between vertical and circumferential or radial directions with a 10 mm/min-compression rate. This response is probably a direct consequence of the orientation of collagen fibres.

Animals↗
PubMed2005

[Core decompression of the femoral head for avascular necrosis].

PURPOSE OF THE STUDY: Core decompression of the femoral head is a conservative surgical treatment with controversial efficacy. We studied retrospectively a series of 32 cases of femoral head osteonecrosis treated by core decompression between 1988 and 2000 in 25 patients. We examined the epidemiological and clinical features as well as the laboratory findings, comparing cases requiring secondary hip replacement and those who had a favorable outcome. We search for prognostic factors. MATERIAL AND METHODS: The series included 32 hips, one case was lost to follow-up. Mean age at decompression was 41.3 years (22-55). In eight hips, osteonecrosis was favored by corticosteroid treatment, in three by chronic alcoholism, and in one by hypertriglyceridemia. No favoring factors were present for 20 hips. According to the ARCO classification there were 15 stage I hips, 13 stage II, 3 stage III, and one stage IV. Core decompression was centered in 24 hips and mean time to decompression was 6.4 months (14 days to 40 months). We reviewed hips without a total prosthesis using the Postel-Merle-d'Aubigne function score and for the radiological assessment the ARCO stage and the Koo index. RESULTS: Favorable outcome was noted in 12 hips. Total hip arthroplasty was required for 19, one hip was lost to follow-up. Mean follow-up in the success group was 82 months (26-176) and mean "time of participation" in the failure group was 11 months (1-38). Mean survival after core decompression was 14 months. Time between onset of symptoms and decompression did not influence outcome. Lesions which remained asymptomatic before decompression remained stable. The stage I hips did not have more favorable outcome than the stage II hips (p < 0.05). Stage III or IV hips had unfavorable outcome. Hips with a Koo index > 40 had a poor outcome (p < 0.05). DISCUSSION: Epidemiological factors which can worsen outcome after core decompression for osteonecrosis are controversial in the literature. Early stage disease (I or II) is considered as an ideal indication for decompression, but is insufficient alone to guarantee success. As other authors, we consider that ARCO stage III and IV and a Koo index > 40 are contraindications for decompression. Improved outcome after core decompression can only be achieved by limiting indications.

Adrenal Cortex Hormones↗
PubMed2005

[Recent fractures of the radial head associated with elbow instability treated with floating Judet prosthesis].

PURPOSE OF THE STUDY: Fracture of the radial head associated with elbow instability is infrequent. We report a retrospective series of floating Judet prostheses implanted for comminutive fractures of the radial head associated with elbow laxity caused either by dislocation or rupture of the medial collateral ligaments. MATERIAL AND METHODS: The series included ten patients who underwent surgery from October 1996 to September 2002 at the Amiens University Hospital. The indication for radial head prosthesis was established in the emergency setting for fracture unamendable by osteosyntheis and elbow laxity. Mean age was 48.2 years (25-69). All patients were seen at mean follow-up of 31.7 months (18-48). According to the Mason classification as modified by Johnson, all patients had type 4 fracture. A Judet radial head prosthesis with a floating metallic cup was implanted in all patients. An investigator other than the operators evaluated outcome using the Mayo Clinic criteria. RESULTS: Joint motion as measured by goniometry was: mean flexion 121degrees (90-140 degrees), mean extension deficit 20 degrees (5-60 degrees), mean pronation 45 degrees (0-85 degrees), mean supination 42.5 degrees (0-90 degrees). The Mayo clinic score was excellent in 3, good in 2, fair in 3, and poor in 2 (prosthesis dislocation in one and hung prosthesis requiring removal in one). Four patients developed periarticular ossifications compromising the final result. DISCUSSION: The floating Judet prosthesis allows optimal adaptation of the implant to anatomy and function. For us, these implants are indispensable when the radial head fracture is associated with elbow instability. The indication for prosthesis may be questionable if the non-fixed fracture is free of associated ligament injury, as suggested by the good long-term reported after simple resection. Rigorous operative technique is crucial, with careful restitution of the radial height. The quality of the result is related to the degree of capsule and ligament injury even after optimal implant positioning. Preventive treatment against periarticular ossification should be systematic.

Adult↗
PubMed2004

The myocardial sleeves of the pulmonary veins: potential implications for atrial fibrillation.

Atrial fibrillation (AF) is the most common abnormal heart rhythm and contributes to cardiac morbidity and mortality. Electrophysiological studies with pacing have shown that AF is initiated by ectopic beats localized in the pulmonary vein (PV) walls. The aim of this work was to look for some anatomical or histological particularities to explain these ectopic beats. Ten autopsied hearts were examined (6 males, 4 females). The myocardium was studied from the left atrium to the PV. Histological sections were made from 39 PVs. Myocardial cells were localized to PV between 9 and 38 mm from the PV-atrial junction. The sleeve was composed of circularly and longitudinally oriented bundles of cardiomyocytes. The peripheral end of the myocardial sleeve was irregular. The longest myocardial sleeves were found in the superior veins and were longitudinally oriented. At the PV-atrial junction, the circular bundles were not often circumferential. PV myocardial architecture confirmed the possibility of initiating AF. This fact is important for therapeutic radiofrequency ablation and explains why PV disconnection is essential.

Atrial Fibrillation↗
PubMed2004

[Ankle arthrodesis after failure of a total ankle prosthesis. Eight cases].

UNLABELLED: We report outcome in eight cases of ankle arthrodesis after failure of a total ankle prosthesis. MATERIAL AND METHODS: This series included eight patients, mean age 57 years (range 36-76) who had initially: post-traumatic talocrural joint degeneration (n=4), rheumatoid polyarthritis (n=3), idiopathic talocrural degeneration (n=1). Three patients had a New Jersey (DePuy) cemented prosthesis, four had a Star (Link) uncemented prosthesis and one, whose implantation was performed in another institution, had a spherical cemented prosthesis. The preoperative Kitaoka score was 19.1 (0-32). Seven patients had subtalar joint degeneration; one patient had a subtalar arthrodesis. The tibial component was cemented alone in two patients, the talar piece in three (two with talar fracture). Failure resulted from loosening, talus fracture or deep infection. Bipolar loosening was observed in two patients. Time to revision was 36 months (range 4-108). Arthrodesis was associated with an iliac graft for seven patients: several tricortical grafts (vertical alignment of the corticals) and cancelous grafts for filling. The height of the graft was adjusted to the substance loss. A bone graft could not be used in one patient who had a deep infection. The arthrodesis was fixed with an anterior plate bridging the talocrural space in six patients, with an external fixator in infected patient, with a conventional centromedullary tibial nail transfixing the talocrural joint and planted in the talus and the calcaneus in one. Outcome was assessed with the Kitaoka score. Mean follow-up was 56 Months (range 10-114). RESULTS: The overall Kitaoka score improved to 54/100 (range 42-70) at last follow-up. The arthrodesis provided improvement in all patients although the final outcome was still considered poor in three patients. Radiographic healing was obtained in seven patients at a mean 3.1 months (range 2.5-6). Wound healing was slow in two patients. One patient developed a deep infection early. DISCUSSION: The rate of fusion was 87%. This is in the general range reported in the literature; use of an iliac graft allows preserving joint height but because of the poor bone quality often encountered, residual bone stock may be insufficient to achieve complete fixation with screwing. Plate fixation appears to be a better way of achieving fixation. This provides a rate of fusion comparable with earlier series where external fixation was generally employed. For us, external fixation should be reserved for infected cases. Use of a conventional anterograde nail can be another solution in the event of poor bone quality. The overall result remains relatively modest although all the patients achieved a functional gain with arthrodesis. The results obtained are less satisfactory than after first-intention ankle arthrodesis.

Activities of Daily Living↗
PubMed2004

[The cementless Duraloc acetabular component: 100 cases assessed after a minimum five year follow-up].

PURPOSE OF THE STUDY: The longevity of an acetabular implant depends in part on its resistance to mechanical stress. Long-term stability of an uncemented cup requires stable primary fixation. This can be achieved with press-fit components. MATERIAL AND METHODS: One hundred forty-nine Duroloc press-fit acetabular implants were studied after a minimum follow-up of 60 months. Among these 149 cups, 100 were analyzed with a mean follow-up of 60 months. Twenty-two patients were lost to follow-up, 19 were contacted by telephone, and eight had died. Clinical and radiological criteria were used to assess outcome. Digitalized x-rays were processed with Imagika (View Tec, Saint-Maurice, France) to determine the position of the implant in two-dimensional space, inclinaison, anteversion, polyethylene wear, bone-implant contact, and presence of ossifications. Seventy percent of the patients underwent arthroplasty for degenerative hip disease. RESULTS: The cohort included 40 women and 60 men. Mean age at surgery was 59.4 years, range 30-80 years. The Postel-Merle-d'Aubigne score improved from 10 to 16. Mean polyethylene wear was 0.5 mm with an annual rate of 0.087 mm/yr. Among the 57 cup-bone spaces present postoperatively, 41 had filled at last follow-up (78%). There were no cases of osteolysis. Peri-prosthetic ossifications were observed in 50 patients (16 stage I, 12 stage II, 19 stage II, and 3 stage IV). Medial displacement of the cup > 4 mm was observed in one patient and ascension > 4 mm in four patients who had no other sign of loosening. Complications were: dislocation (n=15), phlebitis (n=2), sciatalgia (n=1) and infection (n=1). DISCUSSION: This retrospective series revealed an unacceptable dislocation rate with no correlation with implant positioning error in comparison with the biomechanical position of the healthy hip. The non-hemispheric shape of the implant and the beveled edge of the polyethylene insert could be implicated, particularly since none of the implants had a polyethylene overhang. The mean annual wear (0.087 mm) was relatively high compared with cemented cups. Age was the only factor correlated with wear. Migrations were difficult to interpret. Medialization or ascension of the implant was not associated with any clinical sign suggestive of loosening. The poor reproducibility of the x-rays cannot explain these findings. Secondary repositioning of the implant might be involved. CONCLUSION: The high rate of dislocation and the frequency of excessive wear have led us to abandon this implant for more hemispheric cups.

Adult↗
PubMed2004

[Dislocation of the proximal tibio-fibular joint due to severe leg and knee trauma].

PURPOSE OF THE STUDY: Dislocation of the proximal tibio-fibular joint is a rare lesion generally described in athletes. In our experience, high-energy trauma in traffic accident victims was a frequent cause. Dislocation of the proximal tibio-fibular joint is generally described as anterolateral, posteromedial, superior, or subluxation. We describe an inferior form of dislocation. MATERIALS AND METHOD: The study population included eight men aged 21-55 years (mean 31 years). One patient had bilateral dislocation. There were four superior, one posterior, and four inferior dislocations. All patients also had an associated fracture of the tibia which was an open fracture in eight cases. Five patients suffered a lesion to the common fibular nerve. Three had tibial nerve involvement in a context of inferior disclocation. The lateral collateral ligament was torn in six cases. The central pivot was involved in four. Two patients had an avulsion of the patellar ligament on the tibial tuberosity. Five patients had vessel damage. Three required emergency amputation. Two patients (one superior and one inferior dislocation) underwent emergency bypass surgery but required below-knee amputation later due to persistent ischemia. All dislocations, excepting the one case of complete fibular avulsion and one emergency above knee amputation were treated by transarticular screw fixation of the proximal tibio-fibular joint. RESULTS: Mean follow-up was 5.8 years (1-9 years). At last follow-up, there were no cases of instability or pain in the proximal tibio-fibular joint. The patient with an initial neurapraxia in territory of the common fibular nerve recovered totally. The five amputated patients had prostheses and walked without crutches. DISCUSSION: Dislocation of the proximal tibio-fibuilar joint is a rare entity, but the frequency is probably underestimated. The dislocation can go unrecognized in patients with multiple injuries. Careful search should nevertheless be undertaken due to the risk of secondary involvement of the common fibular nerve. The Harrisson and Hindenach classification, inspired by the Lyle classification, does not mention inferior dislocation of the proximal tibio-fibular joint, a recently described entity. Our series included dislocations resulting from high-energy trauma associated with numerous ligament, nerve, and vessel injuries. In this context, dislocation of the proximal tibio-fibular joint constitutes an epiphenomenon.

Adult↗
PubMed2003

[Peri-lunate wrist dislocation: long-term outcome].

PURPOSE OF THE STUDY: We report our experience with 25 peri-lunate posterior wrist dislocations and compare outcome with data in the literature searching for prognostic factors. MATERIAL AND METHODS: Our series included 24 men and one woman, mean age 36 years. Twenty-three patient were less than 50 years old at the time of the accident. Diagnosis was established late in five patients. All patients were reviewed clinically and radiologically with a mean follow-up of 57 months. We differentiated pure dislocations (n=16) from trans-scapho-lunate dislocations (n=9). The pure dislocations included six type 1 and ten type 2 in the Witvoët and Allieu classification. We also distinguished groups by open or closed treatment, with or without pinning, and with or without suture of the scapho-lunate ligament. Screw fixation was used in case of scaphoid fracture. Post-operative cast immobilization was 45 days on the average, followed by three months of rehabilitation exercises. RESULTS: Residual pain of variable intensity was reported by 22 patients but subjectively, 21 patients considered outcome to be good or very good. Wrist movement was greatly impaired in eight patient with a 60 degrees flexion-extension arc. All patients had a 20% reduction in force compared with the healthy side. According to the Green and O'Brian functional score, outcome was poor in four wrists. The scapholunate space and the sapholunate angles were abnormal in seven wrists. Reduction was insufficient in only one case with the scapholunate space measuring 5 mm after trans-scapho-lunate dislocation. In most of the cases, these poor functional and/or radiographic results coincided with carpal instability which developed early or late after trauma. The most bothersome element in other cases was wrist stiffness. The trans-scapho-lunate dislocations appeared to evolve more favorably than the pure dislocations, but could also cause carpal instability. DISCUSSION: There is a real functional impairment after posterior peri-lunate dislocation. The differences in outcome we observed were not statistically correlated with type of treatment, probably because of the small number of patients, but did reveal certain tendencies. Closed reduction did not always avoid the development of carpal instability and gave only average results. Percutaneous pinning or open reduction did not improve outcome in pure dislocations. It might be good to use scapho-lunate suture more often to obtain better healing and reduce the risk of carpal instability, as has been suggested by certain teams.

Adult↗
PubMed2003

[Gluteus medius tendon tear and degenerative hip disease].

We report three cases of gluteus medius tendon tears discovered fortuitously in patients undergoing total hip arthroplasty. The tears were not suspected from the initial clinical presentation. Sutures were possible in only one patient. Outcome of the hip arthroplasty was very good in all three patients despite lack of tendon repair in two.

Aged↗
PubMed2001

[Risk of deep infection in first-intention total hip replacement. Evaluation concerning a continuous series of 790 cases].

OBJECTIVE: Deep infections of the operative site is a rare but serious complication of first intention total hip arthroplasties. French data on infections are sparse. We studied the incidence, characteristics and potential risk factors for these infections in a consecutive series of 790 total hip arthroplasties performed as first intention implantations in a University Hospital in France. PATIENTS AND METHODS: All patients undergoing first intention total hip arthroplasty surgery between November 1995 and May 1999 were included in this study. Demographic, clinical, therapeutic and surgical data were collected. Deep infection was defined as proven presence of microorganisms in at least two preoperative samples during revision surgery. Patients were followed for 1 month to 4 years. Potential risk factors were identified with univariate analysis. Chi square and exact Fisher test were used. RESULTS: The overall incidence of deep infections was 1.11 per 100 implantations (95% CI 0.84-2.70). Delay to development ranged from 14 days to 32 months. Eleven infections were proven within the first year and 3 after one year. Two risk factors were identified: absence of systemic antibiotic prophylaxis (RR = 4.74, p = 0.03) and drainage discharge after 48 hours (RR = 3.62, p = 0.02). Other variables associated with infection with a relative risk greater than 2 were obesity, corticosteroid therapy, development of a hematoma, or difficult postoperative wound healing. CONCLUSION: The incidence observed in this series is slightly higher than generally reported in the world literature. It would be important to write an antibiotic prophylaxis protocol with prescription of systemic antibiotics for all operated patients in order to reduce this incidence. Other measures that could improve the quality of care should also be taken: re-evaluation of preoperative skin preparation protocols, systematic screening of patients carrying Staphylococcus aureus before implantation and proper care for these patients.

Adult↗
PubMed2000

[Surgical treatment of chronic Achilles tendiopathies. Report of 52 cases].

PURPOSE OF THE STUDY: We reviewed a series of 52 cases of chronic Achilles tendinopathy treated surgically by release of the fascia cruris, resection of peritendon, longitudinal incision of the tendon and occasional excision of intratendinous lesions. MATERIALS AND METHODS: The mean course prior to surgery was about 18 months. Twenty-six patients practiced sports. Complaints were bilateral in 12 cases. Pain was always present. Ultrasound exploration evidenced paratendinitis (n=21), tendinosis (n=22) and paratendinitis with tendinosis (n=9) (Puddu classification). Patients were reviewed after a minimal 2-year follow-up. Results were assessed on the basis of clinical findings. RESULTS: Mean follow-up was 5 years 6 months. Twenty-nine patients were free of pain. The range of motion was normal in 48 cases and 29 patients resumed sports activities at the same level as prior to surgery. Outcome was very good in 29 patients, good in 14 average in 6 and poor in 3. DISCUSSION: Stiffness of the tibio-tarsal joint can be avoided by proper mobilization. Outcome appears to be better in middle-aged patients. Poor outcome is closely related to amyotrophy. The presence of a foot deformity does not appear to have an unfavorable influence on outcome. The Achilles tendon must not be infiltrated. Ultrasound is highly contributive, but MRI provides a more accurate analysis. CONCLUSION: Surgical treatment of chronic Achilles tendinopathies can be proposed when conservative treatment has been unsuccessful. Outcome is better in young active patients and in cases where paratendinitis predominates.

Achilles Tendon↗
PubMed1999

[A novel approach to the biomechanical study of the talocrural joint in man using MRI. Contribution of dynamic images].

A cineradiographic study of the talocrural joint allows a new biomechanical approach of the ankle: MRI with axial and coronal slides were realized: for volume reconstruction in passive movement; scanner was used for axial slides in active movement. There is evidently neither distosis of the bimalleolar grip in dorso- and plantar flexion, nor movement of the lateral malleolus of the fibula, in opposition to the classical description. An anatomical rotation is discussed.

Adult↗
PubMed1999

[Percutaneous tenorrhaphy for Achilles tendon rupture. Study of 29 cases].

PURPOSE OF THE STUDY: Closed percutaneous repair, described first by Ma and Griffith in 1977, have bridged the gap between surgical and conservative treatment of Achilles tendon rupture. The purpose of this study was to evaluate the results of percutaneous repair. MATERIAL AND METHODS: Between 1994 and 1996, 28 patients (18 male, 10 female) with 29 spontaneous ruptures of the Achilles tendon (one bilateral case) underwent percutaneous repair based on approximation and bringing closer both ends of the ruptured tendon using a subcutaneous suture. Material used was 2 Dacron yarn suture 30 cm length fitted with a 5 mm wide harpon and with its other end crimped into a malleable needle 12 cm length. Early mobilization was encouraged, partial weight bearing allowed at 3 weeks and full weight bearing at 6 weeks. Sutures were removed at 8 weeks without anesthesia. Two patients were lost for follow up after complication, one foreign patient returned to his country with good results, 26 tendons underwent physical examination at an average follow up of 15 months; 20 underwent ultrasound examination and Cybex testing. RESULTS: Two patients experienced reruptures after suture removal; 2 patients fell a few days after repair and had rupture of the suture; both were treated with a cast. There were no infection, skin necrosis, hematoma, neurological injuries, or deep vein thrombosis. Eighteen patients were free of pain, 7 had intermittent pain and one permanent pain. Active and passive ankle motion were similar to the contralateral side. Calf circumference measurements on the repaired and normal extremities showed a difference of less than 3 cm in 4 cases, less than 2 cm in 13 cases and 9 patients had symmetrical calves. The average difference between the width of the repaired and normal tendon was 0.5 cm. Clinical documentation of muscle strength was normal in 9 cases, decreased in 14 cases. Three tendons could not be tested. Using the Trillat and Mounier-Kuhn score, 12 patients were rated excellent; 7 good, 7 fair and 4 poor (4 complications). Ultrasound examination demonstrated homogeneous and fibrilate structure in 10 cases. The width of the tendon was found increased in all cases. The strength, power and endurance testing performed on Cybex at 90 degrees and 180 degrees/second and compared to the normal ankle, averaged 65 p. 100 for plantar flexion. DISCUSSION: Complication rate of operative and conservative treatment were compared to percutaneous repair. The results of Cybex testing points out the advantages of early mobilization after Achilles tendon rupture treatment. Ultrasound examination is useful to guide post operative rehabilitation and sports activities. All patients return to work more quickly after percutaneous repair. CONCLUSION: Percutaneous repair of the Achilles tendon is a simple, easy and reliable technique. It seems to fulfil the required conditions: bringing closer tendon ends, maintenance of strong contact, preservation of all anatomical and histological factors inducing healing and a rapid return to social and working activities.

Accidents↗
PubMed1999

[Uretero-acetabular fistula after removal of a septic total hip prosthesis].

The authors report a case of an uretero-acetabular fistula after a Girdlestone procedure. The reason of ablation was an infected hip prosthesis. The urinary fistula was treated with an uretero-ileoplasty and hip infection with a two stages procedure. There was no recurrence of infection at two years follow-up. Different causes of this urinary complication are discussed.

Acetabulum↗
PubMed1997

[Femoropatellar osteoarthritis treated by prosthesis. Retrospective study of 50 implants].

MATERIAL AND METHODS: 51 prosthesis were performed in 47 patients and were studied in order to assess long term results. One patient was lost for follow up. The diagnosis was: primitive arthritis in 48 knees and post traumatic arthritis in 3 knees. 25 knees had patellofemoral subluxation, 16 patients had been previously operated on patellofemoral joint. The average age at the time of surgery was 60.5 years and follow up time averaged 3 years. 22 prosthesis had more than 4 years follow-up. The operations were performed using a lateral approach with tibial tubercle osteotomy and lateral patellar retinaculum release. The trochlear component was asymetric and made of chrome cobalt alloy; the patellar component was shaped in polyethylene. Both components were cemented. RESULTS: Using the Guepar scoring system, 41 (82 per cent) PFA were rated excellent or good and 9 poor. Post operative roentgenograms demonstrated patellofemoral alignment in all knees, even in cases of preoperative patellar subluxation, without tilting of the patella. Follow up roentgenograms demonstrated progressive but moderate deterioration of the tibio femoral joint in 9 cases. In 3 cases, more severe tibio femoral arthritis were treated by T.K.R one to three years after P.F.A. In one of these knees, we discovered an asymptomatic loosening of trochlear component. The last 6 poor results were always due to persistent pain. DISCUSSION: The purpose of this study was to assess the results of P.F.A. and to clarify the indications. It appears that the 82 per cent success rate of this study may be compared with the results of literature. All the authors have found P.F.A. to be a viable solution, preferable to patellectomy (even in older patients) or isolated patellofemoral realignment. The clinical and radiological results did not deteriorate with time. Persistent patellofemoral malalignment was not observed in this study thanks to the use of a lateral approach. The presence of tibio femoral arthritis adversely affected the outcome, but accelerated changes on the tibio femoral joint after P.F.A. were not observed.

Adult↗