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G Deschamps

Publications and source records attributed to G Deschamps.

At least 19 recordsLinked to original sources
PubMed2004

[Revision total knee arthroplasty after unicompartmental femorotibial prosthesis: 54 cases].

PURPOSE OF THE STUDY: We analyzed technical difficulties encountered when performing revision total knee arthroplasty in patients with unicompartmental femorotibial prostheses. MATERIAL AND METHODS: This multicentric retrospective study included 54 revisions of unicompartmental femorotibial prosthesis with implantation of a total knee prosthesis. The series included 45 medial and nine lateral compartment prostheses. A gliding total knee prosthesis was implanted in 53 cases (98%) (39 standard, 14 revision). Mean time to failure of the unicompartmental prosthesis was four years. IKS scores were established at review. The radiological work-up included AP and lateral views in single leg stance and goniometry for 22 medial compartment revisions. Twenty-seven patients were seen for physical examination and x-rays and eight were lost to follow-up; data were recorded from medical files for 19 patients. RESULTS: The revision procedure was considered easy in 82% of the cases. Mean follow-up after revision was four years (range 2 - 12 years). Subjective outcome was very satisfactory for 56% of the patients, satisfactory for 36% and unsatisfactory for 8%. The mean function score was 62 points, the mean knee score 85 points, and the mean flexion was 113 degrees. No laxity was found for 90% of the knees. The femorotibial angle was 180 +/- 2 degrees in 46% of the patients. The mechanical femoral angle was 90 degrees in 54% of the patients with 2-4 degrees varus in 42%. The mechanical tibial angle was 90 degrees in 46% of the patients with 2-8 degrees valgus in 37%. Complications included pulmonary embolism (n=2), mobilization under general anesthesia (n=3), arthrolysis (n=1), lateral vertical patellectomy (n=1), and secondary infection (n=1). There were five failures requiring changing the total knee prosthesis. DISCUSSION: Loss of bone stock raises specific problems during revision of unicompartmental knee prostheses. Loss of tibial bone is more frequent but it is more difficult to correct for loss of femoral bone. A gliding knee prosthesis is generally preferred for first intention revision. We recommend a long stem when the bone defect is important or involves loss of cortical bone. We have had good mid-term results with revision total knee prostheses after unicompartmental prostheses. Longer follow-up is needed. Poor results were obtained when revision was performed for persistent pain without a clearly defined cause. The presence or not of significant bone loss did not appear to affect outcome. The observation of medial laxity in case of failed lateral unicompartmental prostheses suggests a more constrained total knee prosthesis might be indicated. Compared with earlier series, our results with total knee prostheses after unicompartmental prostheses appear to be better than after tibial valgus osteotomy and also better than after total knee arthroplasty. Conversely, they would be less satisfactory than for primary total knee arthroplasty. The surgical procedure for revision total knee arthroplasty after unicompartmental prosthesis requires precision and skill but is not technically difficult.

Aged↗
PubMed2004

Alignment influences wear in the knee after medial unicompartmental arthroplasty.

Failure of a medial unicompartmental arthroplasty may be related to wear of the cartilage in the opposite compartment or to wear in the polyethylene tibial implant. Limb alignment influences both of these factors in the long term. Fifty-eight knees with medial unicompartmental arthroplasties in patients alive at least 10 years postoperatively were evaluated for radiographic changes at their most recent followup. The average duration of clinical and radiographic followups for these patients was 15 years (range, 10-20 years). Alignment was measured preoperatively and postoperatively as the hip-knee-ankle angle on radiographs of the entire limb. An overcorrection in valgus of the preoperative deformity (hip-knee-ankle angle > 180 degrees was associated with an increased risk of degenerative changes in the opposite compartment. Severe undercorrection in varus of the deformity (hip-knee-ankle angle < 170 degrees) was associated with increased wear in the tibial component and recurrence of the deformity which was indicative of polyethylene wear. For medial implants that were implanted in moderate varus (hip-knee-ankle angle of 171 degrees to 179 degrees) the rate of wear of the polyethylene was less than in knees with severe undercorrection and the risk of degenerative changes in the opposite compartment was low.

Analysis of Variance↗
PubMed2002

Patellar impingement following unicompartmental arthroplasty.

BACKGROUND: Patellofemoral complications (osteoarthritis and impingement) have been rarely reported after unicompartmental arthroplasty, and their long-term consequences are not known. The purpose of the present study was to analyze these complications following unicondylar arthroplasty. METHODS: We evaluated the results of ninety-nine unicompartmental arthroplasties that had been performed in eighty patients with osteoarthritis of the knee. The medial compartment was replaced in seventy-four knees and the lateral compartment, in twenty-five. All ninety-nine knees were evaluated with regard to patellar impingement and osteoarthritic changes on skyline radiographs after an average duration of follow-up of fourteen years (range, ten to twenty years). In addition, the seventy-seven knees (fifty-eight patients) that had not been revised were evaluated with use of the clinical scoring system of the Knee Society and specific questions regarding patellofemoral symptoms after an average duration of follow-up of fifteen years (range, ten to twenty years). The relationship between patellar complications (osteoarthritis and impingement) and the position of the femoral component was evaluated with use of lateral radiographs of the knee. RESULTS: At the time of the most recent follow-up, twenty-nine knees had osteoarthritic changes in the portion of the patellofemoral joint opposite the compartment with the implant and twenty-eight knees had impingement of the femoral component on the patella. The knees that had impingement did not have osteoarthritic changes. Pain while ascending or descending stairs and pain on rising from a chair were noted more frequently in knees with patellar complications (impingement and osteoarthritis) (p = 0.02), and these symptoms affected the stair-climbing functional score. These symptoms were more severe in knees with patellar impingement than in knees with degenerative changes. One revision was performed because of patellar impingement. Patellar impingement was more frequent after lateral arthroplasty than after medial arthroplasty (p = 0.02) and was associated with placement of the femoral component too far anteriorly (p = 0.001). CONCLUSION: After unicompartmental arthroplasty, the patellofemoral joint was affected by degenerative changes and patellar impingement. These complications appeared to have been mutually exclusive and affected the functional outcome of the arthroplasty. Patellar impingement affected the knee more severely with regard to both symptoms and the need for revision.

Adult↗
PubMed2001

Metabolic engineering of Escherichia coli: construction and characterization of a gltA (citrate synthase) knockout mutant.

E. coli is one of the most important host organisms for recombinant protein production. However, growth and recombinant protein production can be limited by acetate accumulation during high-cell-density fermentations. Some of the strategies used to overcome this problem are based on the alteration of the genotype of the host. This paper discusses the construction and characterization of an E. coli gltA- knockout mutant. The knockout of the gene was confirmed by the loss of citrate synthase activity in an enzyme assay. Also the growth rate of the mutant on Luria Broth and Luria Broth + acetate was reduced.

Citrate (si)-Synthase↗
PubMed2000

[Revision in non-infected total knee arthroplasty: an analysis of 69 consecutive cases].

PURPOSE OF THE STUDY: We reviewed 69 consecutive cases of total knee arthroplasty revisions to analyze the causes of failure. MATERIAL AND METHODS: Sixty-nine total knee arthroplasty revisions were required between 1990 and 1997 for non-septic failure. Five categories of failures were identified: 30 loosenings including 11 with an initial malposition (varus position of the tibial component in 8 cases), 14 laxities (medial in 5, lateral in 5 and anteroposterior in 4), 11 stiff knees with no other clinical or radiological anomaly, 6 patellar failures (2 dislocations, 2 cases of excessive wear, 2 painful knees with a Freeman prosthesis), and 8 cases of painful knees with no other detectable anomaly. RESULTS: A three-phase reconstruction procedure was used after removing the failing TKA: 1) reconstruction of the tibia with replacement of lost bone, 2) reconstruction of the femur with balanced flexion determining the size of the implant, 3) balanced extension determining the distal/proximal position of the femoral component. A "simple" sliding prosthesis was used in 16 cases, a modular reconstruction prosthesis in 40 cases and a hinge prosthesis in 13 cases. Mean follow-up for functional and radiographic assessment after revision surgery was 37 months (59 cases) with a minimum follow-up of 1 year. The best outcome was observed in the "loosening", "laxity", and "stiffness" patients. Outcome was less favorable for the group "isolated pain" with IKS functional scores of 35.5 +/- 16 and 52.5 +/- 21. DISCUSSION: In 36 p. 100 of cases, TKA failure was related to a technical mistake (component malposition, poor ligament alignment). In 33 p. 100, failure was patient related (multiple procedures, congenital hip dysplasia, rheumatoid arthritis.). Outcome after revision TKA was less favorable than after primary TKA, particularly in case of painful knees with no other detectable anomaly. CONCLUSION: Surgical revision of TKA must follow a rigorous procedure with a detailed preoperative work-up. The decision for revision must not be made unless a precise anomaly has been identified.

Adult↗
PubMed1999

Laxity in posterior cruciate sparing and posterior stabilized total knee prostheses.

Two series of consecutive total knee replacements were compared retrospectively: 118 HLS II posterior stabilized prostheses (Group 1) versus 138 HLS CP posterior cruciate ligament sparing prostheses (Group 2). Both implants were made by the same manufacturer. The prostheses had been inserted between 1989 and 1992. Mean followup was 4 years. The authors looked for evidence of laxity in the coronal and the sagittal planes, the correlation of laxity with other factors, and the effect of laxity on the objective and subjective outcome as measured with the Knee Society score. Group 2 had significantly more clinical and radiologic laxity. There was little difference between the two groups regarding the overall objective and subjective outcome; however, there was a significantly higher rate of excellent results in Group 1. Longer followup will be required to see whether the implants with laxity are at heightened risk for tibial component wear.

Adult↗
PubMed1992

[Total knee replacement after valgus tibial osteotomy. Technical problems].

Forty total knee replacements following valgus tibial osteotomy were analysed. There were 38 patients (10 men and 28 women) with a mean age of 72 years at the time of the joint replacement, at a mean of 8.5 years after osteotomy. Mean follow-up was 3 years (1 to 5 years). Performing a total knee replacement after valgus tibial osteotomy posed some specific problems due to asymmetrical bone cuts, residual ligament laxity, loss of bone at the tibial plateau, and especially when there was a malunion of the previous osteotomy. The functional results were good. A group of 208 patients with total knee replacements for untreated osteoarthritis acted as a control for comparison. In the group with an osteotomy the results were worse in respect of the walking distance and flexion angle achieved after joint replacement compared with primary replacement (p < 0.001). However the GUEPAR and HSS score 77.2 +/- 2.3 were very similar. Using unilateral weight-bearing X-rays, 18.8p. 100 demonstrated opening from ligament laxity and 40.6p. 100 had radiolucent lines under the components, which was the same as in the control group. The tibio-femoral mechanical axis using long-leg films had a mean varus angle of 0.7 degrees.

Aged↗
PubMed1988

[Maternity and extreme poverty. Ways of supervising pregnancy and delivery].

In women living under extreme poverty conditions, isolation, absence of social support, stress, seem to play a major role in the morbidity of pregnancy. In spite of thorough monitoring and frequent hospitalization, morbidity remains. This study stresses that the follow-up of pregnancies should not only be characterized by a quantitatively increased medical monitoring, but also by a warmer relationship between women living in a disadvantaged environment and health personnel.

Adolescent↗
PubMed1987

[Rupture of the anterior cruciate ligament: a frequently unrecognized cause of failure of unicompartmental knee prostheses. Apropos of a series of 79 Lotus prostheses with a follow-up of more than 5 years].

Out of 386 unicompartmental prostheses inserted in the Orthopaedic Centre in Dracy Le Fort between 1977 and 1986, 79 cases in 68 patients with a follow-up equal to or more than five years and a mean of seven years were able to be reviewed. This study showed that 75 per cent of knees had a satisfactory result and 25 per cent were failures. Apart from well-recognised causes of failure such as rheumatoid arthritis, overcorrection or the use of a six millimetre tibial plateau, the authors discovered a frequent cause not clearly recorded in the literature--that is anterior cruciate laxity. This situation was found retrospectively in the pre-operative weight-bearing radiographs. Out of 15 knees showing a pre-operative laxity equal to or greater than 10 mm in the lateral radiograph, 13 were failures and 10 were operated on again after a mean of three-and-a-half years. An investigation of anterior cruciate laxity should be made systematically by weight-bearing lateral radiographs, if necessary with stress views, before recommending a unicompartmental prosthesis.

Aged↗
PubMed1987

[Arthrosis of the knee in chronic anterior laxity].

Arthrosis following rupture of the anterior cruciate ligament has been analysed in two series. The first series was derived from a review of 150 cases of reconstruction of the anterior cruciate ligament with a follow-up of 3 years or more. Arthrosis was seen to have developed in 13.3%. The second series was concerned with 64 cases of unilateral arthrosis treated by upper tibial valgus osteotomy in whom there had been a previous rupture of the anterior cruciate ligament. The "tolerance time"--that is the time between the original ligamentous injury and the time of osteotomy--for the development of arthrosis was very variable, ranging in cases with a "natural history" from 10 to 50 years with a mean of 35 years. It is important to recognise the radiological signs of the onset of arthrosis. These are osteophytosis of the intercondylar notch, osteophyte formation at the posterior part of the medial tibial plateau, and, in particular, narrowing of the medial joint line with posterior subluxation of the medial femoral condyle, well seen in lateral radiographs whilst standing on one lower limb. Early arthroses, appearing after 10 years, may occur as a "natural arthrosis", but it develops much more frequently after surgical treatment that had failed to correct anterior laxity and particularly when it had been performed on knees that were already pre-arthrotic. The main factor in arthrosis is anterior laxity measured radiologically by an "active Lachman" radiograph. Removal of the medial meniscus, which, in itself, is liable to produce arthrosis is even more harmful in anterior cruciate laxity since it doubles the degree of anterior subluxation of the tibia seen on unilateral weight-bearing. The development of varus deformity, which characterises progressive arthrosis, has its origin in wear of the posterior part of the medial tibial plateau caused by anterior cruciate laxity. Other factors play an important part such as associated lateral laxity, constitutional genu varum and weakness of the hamstring muscles which oppose the subluxating action of the quadriceps.

Adult↗
PubMed1984

Pancreatic carcinoma: surgical treatment.

There is controversy in the literature over the surgical treatment of pancreatic carcinoma, especially whether gastro-enterostomy should be performed prophylactically when palliative biliary bypass is done. The authors report a retrospective study of 184 patients with pancreatic carcinoma treated at the Hôtel-Dieu Hospital in Montreal between 1970 and 1982. Of these, 106 patients had cancer of the head of the pancreas. In this group, 15 had a Whipple procedure. Median survival was 512 days with no 5-year survivors. Forty-nine patients had biliary bypass alone and 3 needed gastroenterostomy later for duodenal obstruction. Eleven patients had both biliary--enteric bypass and gastroenterostomy. Biliary bypass using the common duct gives the same result as that using the gallbladder. Considering their reoperation rate of only 7.3%, the authors do not believe that prophylactic gastroenterostomy is indicated in these patients.

Aged↗
PubMed1983

Idiopathic osteonecrosis of the knee. Aetiology, prognosis and treatment.

This is a prospective study of 105 knees in 91 patients with idiopathic osteonecrosis of the femoral condyles, with an average follow-up of five years in 101 knees. Forty-eight of the 75 patients in whom the body weight was studied were obese and four of the 33 patients in whom a densitometry study was done showed decreased bone density. Prognosis is unfavourable if the lesion is larger than five square centimetres and if its width is more than 40 per cent of that of the condyle. Of the 22 patients followed up after conservative treatment 80 per cent were satisfactory. Of the 11 knees treated by arthrotomy alone 55 per cent were satisfactory. Of the 31 knees treated by osteotomy (21 with associated arthrotomy) 87 per cent were satisfactory. Arthrotomy did not significantly improve the results of osteotomies. The ideal correction was to 10 degrees of valgus. Of the 37 knees treated with replacement 95 per cent were satisfactory, and the best results were obtained with the total-condylar prosthesis.

Adult↗
PubMed1983

[Cinematic study of the cervical spine during flexion-extension movements].

By means of dynamic roentgenographic study (5 to 7 X-rays) of the cervical spine in sagittal plane, the authors were able to define: amplitudes of each intervertebral joints. C4, C5 and C6 are the more mobile levels, position of instant centers of rotation for each intervertebral joint in healthy and pathologic individuals. This method allows a kinematic diagnosis of discopathies.

Biomechanical Phenomena↗
PubMed1982

[Patella infera. Apropos of 128 cases].

A low patella is frequently a complication of a lesion of the knee but it can also present secondary symptoms of its own. The authors describe an original method for assessment of the vertical level of the patella. They have tried to establish a relationship between the low situation of the patella and pain of a certain type associated with limited flexion of the knee. Physiopathological and biomechanical evidence is taken into account. In most instances, a low patella is secondary either to a mechanical cause, natural or iatrogenic, or to an inflammatory cause such as algodystrophia. 29 patients out of 128 observed cases have been operated on. 17 of these were due to excessive transplantation of the anterior tibial tubercle. In most of the cases the tibial tubercle was transplanted upwards in association with a joint release. In only 3 cases a patellectomy was done. The results were excellent or good in half of the cases and unsatisfactory in the other half.

Adult↗
PubMed1982

[Incidence of child abuse. Evaluation and criticism of information sources and results].

In a 500,000 inhabitants French area, the authors studied how school and social services perceived the problem of child abuse, what were their definitions for it and the cases they had reported in 1979, on the basis of these definitions. Definitions were homogeneous from one service to another. However, facing concrete situations, several services restricted the field of child abuse and considered only severe active physical injury; facing the same cases various services have different opinions. Nevertheless, with respect to the large number of services studied, the incidence of child abuse could be estimated: at least one out of 150 children under 6 years suffers each year from more or less severe maltreatment. Moreover, this investigation gave interesting information concerning the way these services work in the field of child abuse.

Child↗