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P Chambat

Publications and source records attributed to P Chambat.

At least 19 recordsLinked to original sources
PubMed2006

[Adult lateral meniscus].

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

Cysts↗
PubMed2005

[Not Available].

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Journal Article↗
PubMed2005

[Not Available].

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Journal Article↗
PubMed2005

["Isolated" injury of the posterior cruciate ligament. Surgical treatment of isolated posterior cruciate ligament tears: a multicentric retrospective study of 103 patients].

PURPOSE OF THE STUDY: We present a retrospective multicentric series of carefully selected patients presenting "isolated" laxity of the posterior cruciate ligament. MATERIAL AND METHODS: The series included 103 patients who were reviewed clinically (with a dedicated review chart) and radiographically with measurement of posterior laxity (Telos 15 kg). RESULTS: In these patients with an isolated injury of the PCL (without associated injury of the peripheral ligament) DISCUSSION: The short follow-up of this series (four years) does not enable an assessment of the risk or benefit of PCL ligamentoplasty for arthrosic knees.

English Abstract↗
PubMed2004

[Current status of valgus angle, tibial head closing wedge osteotomy in media gonarthrosis].

In young and active patients, closing-wedge high tibial osteotomies are reliable procedures in the treatment of osteoarthritis of the medial compartment of the knee. This has been consistently shown throughout the last 2 decades. The present study analyzes the long-term results of 217 patients after an average of 9 years and compares them to the results in the literature. Besides correction of the alignment, other prognostic factors such as the patients' age, overweight, the preoperative degree of osteoarthritis, but also a newer prognostic factor described by the Lyon knee school have been evaluated. The authors found that the "tibial bone varus angle" might be helpful to differentiate between a bony deformity of the proximal tibia, amenable to correction by osteotomy, and a secondary bony erosion of the medial tibial plateau, with a worse prognosis.

Adult↗
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↗
PubMed2003

A comparative study of medial versus lateral arthroscopic partial meniscectomy on stable knees: 10-year minimum follow-up.

PURPOSE: Our goal was to compare results of partial medial arthroscopic meniscectomy with results of partial lateral arthroscopic meniscectomy and to determine prognostic factors. TYPE OF STUDY: Retrospective comparative study with statistical analysis. METHODS: In this study, 362 medial and 109 lateral isolated arthroscopic meniscectomies are presented with a minimum follow-up time of 10 years. All knees were stable with no previous surgery or traumatic lesion. RESULTS: In this study, 95% of the patients were very satisfied or satisfied with the results of the medial meniscectomy, and 95.5% with results of the lateral meniscectomy (P =.32). According to grades 1 and 2 of the International Knee Documentation Committee (IKDC) form, 85.8% of the medial meniscectomy group were free of any symptoms, as were 79.7% of the lateral meniscectomy group (P =.11). Radiologic changes after medial and lateral meniscectomy were found in 21.5% and 37.5%, respectively (P =.11). The rates of radiologic changes in patients in whom the contralateral knee was radiologically normal were 22.3% and 39%, respectively (P =.016). The rate of repeat surgeries for osteoarthritis was less than 0.2%. CONCLUSIONS: Subjective and clinical results after medial or lateral meniscectomy are quite similar, but radiologic results are significantly worse after lateral meniscectomy. The most accurate way to determine the degeneration caused by the meniscectomy is to evaluate joint space narrowing in patients in whom the contralateral knee was radiologically normal. Otherwise, partial medial or lateral meniscectomy are well tolerated. A better prognosis can be predicted for a patient with an isolated medial meniscal tear with one or more of the following factors: age less than 35 years, a vertical tear, no cartilage damage, and an intact meniscal rim at the end of the meniscectomy. With an isolated lateral meniscal tear, a better prognosis can be predicted if the patient is young and has an intact meniscal rim at the end of the meniscectomy.

Adolescent↗
PubMed2002

Patellar tendon length--the factor in patellar instability?

Patellar tendon length has been compared in 42 knees with a history of patellar dislocation, and 51 control knees. A lateral X-ray and a magnetic resonance image (MRI) were taken of each knee. The mean radiological patellar tendon length was 46 mm in the controls and 53 mm in the dislocation group. From MRI images, the mean was 44 mm in controls and 52 mm in the dislocation group. This means that the patellar tendon is significantly (P<0.0001) longer in patients with a history of patellar dislocation on both MRI and X-ray. There is no significant difference (P=0.52) between X-ray and MRI measurements of tendon length. The distance between the tibial plateau and the point of tendon insertion was also measured and found to be 28 and 29 mm in the control and dislocation groups, respectively. There is no significant difference between these two measures (P=0.19). In conclusion, patella alta is caused by a long patellar tendon rather than a low insertion into the tibia. Measuring the length of the patellar tendon using MRI is more specific and more sensitive than the Caton-Deschamps index for patellar instability.

Adolescent↗
PubMed2002

[Seventeen year outcome after anterior cruciate ligament reconstruction with a intact or repaired medial meniscus].

PURPOSE OF THE STUDY: Ten-year outcome of anterior cruciate ligament (ACL) reconstruction was previously reported (1992-1993) for 148 patients who had ACL free grafts associated with extra-articular tenodesis. In this retrospective study, we examined the functional and radiological changes observed 17 years after surgery in patients whose menisci were intact or repaired at ACL reconstruction (46 cases). These patients were operated on between 1978 and 1983. MATERIAL AND METHODS: Between January and April 1999, 28 patients were reviewed clinically and radiographically. Nine other patients responded to a questionnaire and three of them sent their x-rays. Two patients had died since the last review and 7 were lost to follow-up. Mean age at follow-up was 41 years. The IKDC classification was A 18.5%, B 51%, C 22.2%, D 7.4% in 26 patients reviewed with the passive radiological Lachman. At subjective analysis (n=37), 70% of the patients were very satisfied and 27% were satisfied. At radiological analysis (n=31), the AP or lateral single-limb stance views and the AP two-limb weight bearing views at 45% flexion demonstrated preosteoarthritis in 22% and osteoarthritis in 3%. Residual anterior tibial translation was the same at 11 years and 17 years follow-up. DISCUSSION: This study clearly demonstrates that ACL reconstruction associated with extra-articular tenodesis can provide good functional and radiological results at 17 years mean follow-up for patients with preserved (sound or sutured) menisci. The status of the medial meniscus at long-term follow-up appears to be the key feature determining the low rate of degenerative changes.

Adult↗
PubMed2001

The natural history of the knee following arthroscopic medial meniscectomy.

We examined the natural history of arthroscopic medial meniscectomy in knees with an isolated meniscal injury by reviewing 317 of 894 cases following medial meniscectomy. At the time of the initial surgery none of the knees had been operated on, and there was no evidence of ligament injury. The patients were reviewed clinically and radiologically after a mean of 11.5 years (range 10-15). The knee was considered "normal" or "nearly normal" by 91% of patients. In 218 patients the contralateral knee was asymptomatic without history of operation or significant injury and could be used as control for comparison. Radiology showed 22.4% greater excess prevalence of joint space narrowing in the operated compared to the control knee. The factors predisposing to a poor radiological result were age above 35 years, the presence of medial compartment cartilage degeneration at the time of the first arthroscopy, resection of the posterior one-third of the meniscus, and meniscal rim resection. Preoperative participation in sport was a predictor of a better outcome.

Adolescent↗
PubMed2000

The axial view in evaluating tibial translation in cases of insufficiency of the posterior cruciate ligament.

The purpose of this report is to present a new radiological method of diagnosis and evaluation of posterior instability using the patellofemoral axial view. During a period of 22 months, we performed clinical and radiological assessments on 20 patients (6 acute and 14 chronic) with isolated posterior instability caused by posterior cruciate ligament (PCL) rupture and on 20 patients with normal knees. The radiological examination included stress radiographs using the Telos device (Telos, Griesheim, Germany) as well as a modification of the routine axial patellofemoral view. Both diagnosis and quantification of the posterior tibial translation was possible in all cases by measuring, on the axial view, the distance between the anterior edge of the tibial plateau and the center of the femoral groove (trochlea). Clinical examination, conventional radiography, KT-1000 arthrometry, stress radiography at 90 degrees and at 20 degrees of flexion, and magnetic resonance imaging all assist in diagnosing a PCL tear. This new radiographic technique is simple, fast, and consistently effective both in patients with acute and those with chronic PCL tears, as well as in those who have undergone PCL reconstruction.

Adult↗
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↗
PubMed1998

[Ligament ruptures].

Ligamentous injuries of the knee are becoming commoner and commoner. They can involve the anterior cruciate ligament, the posterior cruciate ligament, or both ligaments together. The anterior cruciate ligament is the sportsman's injury. The diagnosis is a clinical one, with other diagnostic techniques only being used in the doubtful case. The treatment is well established, with surgery in the young and sportive patient, and a trial of non-operative treatment in the less active patient. The results of treatment are good. The posterior cruciate ligament is injured less commonly, and the diagnosis is sometimes missed. The injury is usually tolerated well, and the results of surgery are less reliable. For these reasons surgery is only performed in carefully selected patients.

Anterior Cruciate Ligament↗
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↗