Recovery of gait pattern after medial patellofemoral ligament reconstruction for objective patellar instability.

Gait pattern alterations were previously reported in association with objective patellar instability (OPI). Gait pattern comparison between a series of patients having undergone medial patellofemoral ligament (MPFL) reconstruction and a sample of control subjects. Thirty patients at 6 months postoperatively after MPFL reconstruction and thirty control subjects were enrolled in the study for a clinical and biomechanical assessment including gait analysis at three selected walking rates using the GAITRite(®) system. The mean raw IKDC score was 73 (± 19), and the mean Kujala knee function was 84 (± 17.5). The study of gait did not demonstrate any significant difference between the two groups at a normal and fast walking rate. At a 10 km/h running speed, the single-support phase was significantly shortened by a mean 2.33% (p < 0.05), the swing phase by a mean 2.64% (p < 0.05) and the double-support phase by a mean 3.49% (p < 0.05) on the operated side. MPFL reconstruction reported good midterm functional and clinical results in the management of OPI. At 6 months postoperatively, the patient gait pattern was similar to that observed in healthy subjects at a normal and fast walking speed. However, our study revealed persistent gait abnormalities at a 10 km/h running speed. These gait alterations seemed to be related to the ligament reconstruction in itself due to the higher strain applied on the reconstructed MPFL during running cycle (10 km/h). Level of evidence IV.

Recovery of rotators strength after Latarjet surgery.

The purposes of this study were to prospectively determine changes in rotator cuff strength before and after surgical shoulder stabilization by Bristow-Latarjet procedure and to better estimate time needed for rotator cuff strength recovery. 20 patients with recurrent anterior posttraumatic shoulder dislocation underwent internal (IR) and external (ER) rotator isokinetic evaluation before and 3, 6 and 21 months after Bristow-Latarjet surgery. In a seated position with 45° of shoulder abduction in the scapular plane, both shoulders were evaluated concentrically with a Con-Trex® isokinetic dynamometer at 180°âˆ™s (- 1), 120°âˆ™s (- 1) and 60°âˆ™s (- 1). 3 months post-surgery, IR and ER strength of the operated shoulder were significantly lower than before surgery (- 28 ± 20% for IR, - 17 ± 17% for ER) (P<0.05). At 6 and 21 months post-surgery, IR and ER strength were comparable to strength before surgery; strength recovery is seen at 6 months post-surgery with long-term maintenance at 21 months. Given the weakness 3 months post-surgery, return to sports (including overhead and contact sports) should be discussed, and 6 months post-surgery may be a better point for an athlete to resume practicing sports. Isokinetic rotator cuff strength evaluation appears to be relevant in helping to determine the need of continuing strength rehabilitation. Pre-surgical evaluation contributes to the relevance of later comparisons.

The role of the medial ligamentous structures on patellar tracking during knee flexion.

PURPOSE: The influence of the medial patellar ligamentous structures on patellar tracking has rarely been studied. Thus the main purpose of this cadaveric biomechanical study was to determine the influence of the medial patellofemoral (MPFL), medial patellomeniscal (MPML) and medial patellotibial (MPTL) ligaments on the three-dimensional patellar tracking during knee flexion. This study was conducted using a validated cadaveric optoelectronic protocol for analysis of patellar kinematics. METHODS: For each cadaveric knee study, four successive acquisitions were performed; first was studied patellar tracking in healthy knees, then the junction between MPFL and vastus medialis obliquus (VMO) was sectioned, the MPFL was released at its patellar attachment and finally was released the insertion of the MPML and MPTL. RESULTS: In this study, the MPFL accounts for 50-60% of the medial stabilization forces of the lateral patellar shift during patellar engagement in the femoral trochlea. This work confirm and clarify the role of the MPFL as the primary stabilizer of the patella during the initial 30° of knee flexion. Moreover, this study shows no significant results regarding the stabilizing action of the VMO on the patella during knee flexion. CONCLUSION: This in vitro study, conducted with an experimental protocol previously validated in the literature, helps quantify the actions of the MPFL, the VMO, and the MPML/MPTL respectively, and identify areas of joint motion where these structures have the most significant influence. This confirms the importance of reconstruction in the treatment of chronic patellar instability. During its reconstruction, care should be taken to adjust the MPFL balance during the initial 20°-30° of flexion.

Is nasal carriage of Staphylococcus aureus the main acquisition pathway for surgical-site infection in orthopaedic surgery?

The endogenous or exogenous origin of Staphylococcus aureus, responsible for orthopaedic surgical-site infections (SSI), remains debated. We conducted a multicentre prospective cohort study to analyse the respective part of exogenous contamination and endogenous self-inoculation by S. aureus during elective orthopaedic surgery. The nose of each consecutive patient was sampled before surgery. Strains of S. aureus isolated from the nose and the wound, in the case of SSI, were compared by antibiotypes or pulsed-field gel electrophoresis (PFGE). A total of 3,908 consecutive patients undergoing orthopaedic surgery were included. Seventy-seven patients developed an SSI (2%), including 22 related to S. aureus (0.6%). S. aureus was isolated from the nose of 790 patients (20.2%) at the time of surgery. In the multivariate analysis, S. aureus nasal carriage was found to be a risk factor for S. aureus SSI in orthopaedic surgery. However, only nine subjects exhibiting S. aureus SSI had been found to be carriers before surgery: when compared, three pairs of strains were considered to be different and six similar. In most cases of S. aureus SSI, either an endogenous origin could not be demonstrated or pre-operative nasal colonisation retrieved a strain that was different from the one recovered from the surgical site.

[Survival of dual mobility socket with a mean 17 years follow-up]. / Etude d'une série de 438 cupules non cimentées à double mobilité

PURPOSE OF THE STUDY: Within the framework of the 2007 symposium of the French Hip and Knee Society devoted to the dual mobility socket, we report a retrospective multicentric series of 438 first-intention total hip prostheses with a dual mobile socket at 17 years mean follow-up. The purpose of our report was to ascertain the 15-year survival and analyze failures. MATERIAL AND METHODS: The series included 438 first-intention prostheses. This was a homogeneous multicentric series. Sockets were: 80 Novae-1 titanium Serf cups and 358 Novae-1 stainless steel Serf cups. All stems were inserted without cement: 185 Pf) stainless steel screwed Serf stems, 228 PRO titanium screwed Serf stems, 25 Corail stems. The mobile polyethylene insert was retaining. All of the heads were 22.2mm chromium-cobalt heads. Degenerative hip disease was the main etiology and mean follow-up was 17.18 years (range: 12-20). Mean age at implantation was 54.8 years (range: 23-87). The actuarial method with 95% interval of confidence was used to determine the 15-year cup survival. RESULTS: At last follow-up, none of the patients had presented an episode of early or late instability. Analysis of the socket at last follow-up showed: 13 aseptic loosenings, 23 intraprosthetic dislocations, and seven replacements of the polyethylene insert for wear. The overall 15-year prosthesis survival was 89.2+/-8.7%. The overall 15-year socket survival was 96.3+/-3.7%. DISCUSSION: The fact that at last follow-up none of the implants had exhibited instability confirms the long-term stability of the dual mobility socket. The results in terms of 15-year survival confirm earlier reports. The main cause of failure was cup fixation, which is the weak point of this technique with the initial Novae cup, which did not have hydroxyapatite coating. The second leading cause was intraprosthetic dislocation, which can be divided into three main categories. The first is intraprosthetic dislocation in a context of pure wear with normal function of the dual mobility; the retaining feature of the insert looses its efficacy due to wear. The second category is intraprosthetic dislocation in a context of cup loosening with a third-body effect and increased retention wear, in which case we consider that the cup loosening is the primary event leading to secondary rapid wear and subsequent intraprosthetic dislocation. The third category is intraprosthetic dislocation cause by a cam effect in a context of fibrosis or impingement involving a large calcification. We have had only two femoral failures by aseptic loosening, most certainly related to use of noncemented implants, which limits the extension of granulomas to the polyethylene. Studying more specifically the three series from Saint-Etienne where three different configurations were used, it would appear that the titanium cup has a better survival and that the titanium used for the thinner necks would be an unfavorable factor for intraprosthetic dislocation.

Prognostic factors for all-inside meniscal repair. A 87-case series.

INTRODUCTION: Repair is indicated for tears in non-degenerative menisci. The literature reports a 15% failure rate for all-inside repair. The aim of the present study was to determine prognostic factors for failure of all-inside meniscal repair. The study hypothesis was that epidemiological, clinical and surgical factors affect success. MATERIAL AND METHODS: A retrospective study included 87 meniscal repair procedures, with or without anterior cruciate ligament (ACL) tear. Lesions were located in red-red or red-white zones. After freshening, repair comprised an all-inside arthroscopic technique using the FasT-Fix® system (Smith & Nephew), with (70.1%) or without ligament reconstruction; all ACL tears were reconstructed. Preoperative data comprised: age, gender, smoking status, sports activity, trauma-to-surgery time, body mass index (BMI), frontal morphotype, and IKDC score. Intra- and postoperative data comprised: meniscal lesion characteristics, location, number of sutures, type of ACL reconstruction, presence of chondropathy, authorized postoperative ranges of motion, and IKDC score. Failure was defined by secondary meniscectomy. RESULTS: At 31 months' follow-up, there were 13 failures (15%). Mean postoperative IKDC score was 88.19 (range: 64.37-98.95). Bucket-handle lesion (P=0.006) and BMI>25 (P=0.014) emerged as significant factors of poor prognosis. DISCUSSION: The present failure rate matched those reported in the literature. The more extensive the lesion, the higher the risk of failure. High BMI incurs mechanical stresses that increase the risk of failure. LEVEL OF EVIDENCE: IV, retrospective cohort study.

[Survival of cementless dual mobility sockets: ten-year follow-up]. / Survie a dix ans d'une cupule double mobilité non cimentée.

PURPOSE OF THE STUDY: We report a retrospective series of 106 total hip prosthesis with ten years follow-up. The purpose of this study was to analyze survival of cementless dual mobility sockets. MATERIAL AND METHODS: The series included 90 consecutive patients with 106 first-intention total hip prosthesis, all with cementless dual mobility sockets. All prosthesis (Novae-1 socket and Profil-1 stem, Serf) were implanted within a 6-month period. The stainless steal socket was coated with alumina and had two short anchorage studs and a superior mooring screw and a polyethylene retentive liner. The stem had a 22.2 mm chromium cobalt head. The main indication for arthroplasty was degenerative joint disease. Mean age at implantation was 56 years (range 23-87). All patients were seen for physical examination and x-rays every two or three years. We noted cup survival at ten years (actuarial method), defining surgical revision for cup replacement due to an aseptic cause as the endpoint. RESULTS: Twelve patients died during the 10-year follow-up and one was lost to follow-up. The Postel-Merle d'Aubligné score improved from 7.1 preoperatively to 15.8 at ten years. There were two isolated acetabular loosenings, two intra-prosthetic dislocations due to advanced wear of the polyethylene insert. The overall survival rate of the socket was 94.6% at ten years. There were no episodes of prosthetic instability in this series. DISCUSSION: This study demonstrates the good ten-year survival of the dual mobility socket, comparable to that of conventional prostheses. The absence of any case of prosthetic instability in this series confirms the good short-term and long-term stability of the dual mobility socket. Intraprosthetic dislocation, due to loss of the polyethylene retaining ring is the main limitation of this method. The incidence was however low (2% at ten years) and treatment was not a problem. We recommend using the dual-mobility socket as the first-intention implant for patients with a high risk of post-operative instability, but also recommend it for all patients aged over 70 years since instability is the leading cause of surgical revision after this age.

Medial patellofemoral ligament reconstruction for patellar instability following total knee arthroplasty: A review of 6 cases.

INTRODUCTION: Patellar instability is a frequent cause of total knee arthroplasty (TKA) failure. In cases of post-arthroplasty patellar instability, the medial structures may be damaged. The objective of this study was to study the effectiveness of medial patellofemoral ligament (MPFL) reconstruction. We hypothesized that MPFL reconstruction will effectively realign the patella, making it a viable treatment option for managing post-arthroplasty patellar instability. MATERIAL AND METHODS: In this retrospective study of six patients treated by four different surgeons, patients were included if they had a recurring or permanent patellar dislocation after undergoing TKA. Patients were excluded if the patellar instability was painful but did not result in dislocation. Each patient underwent MPFL reconstruction using the gracilis; additional procedures could be performed depending on the diagnosis. One patient required TKA revision because of an abnormally rotated femoral implant. The main outcome measure was the non-recurrence of the dislocation. The IKDC and Kujala functional scores, joint range of motion and patellar tilt on X-rays were analyzed preoperatively and at the last follow-up. RESULTS: At a mean follow-up of 23 months (6-46), none of the patients experienced a recurrence of the patellar dislocation. Only one patient had no improvements in the functional outcome scores. The patellar tilt was reduced in all patients. CONCLUSION: MPFL reconstruction-in isolation or with femoral component revision-is effective at treating post-arthroplasty patellar instability. It has its place in the treatment of patellar dislocation following TKA and its indications must be based on exact analysis of the reasons for the instability. LEVEL OF EVIDENCE: IV - Retrospective cohort study.

Ground-reactive forces after hallux valgus surgery: comparison of Scarf osteotomy and arthrodesis of the first metatarsophalangeal joint.

AIMS: The purpose of this study was to analyse the biomechanics of walking, through the ground reaction forces (GRF) measured, after first metatarsal osteotomy or metatarsophalangeal joint (MTP) arthrodesis. PATIENTS AND METHODS: A total of 19 patients underwent a Scarf osteotomy (50.3 years, standard deviation (sd) 12.3) and 18 underwent an arthrodesis (56.2 years, sd 6.5). Clinical and radiographical data as well as the American Orthopaedic Foot and Ankle Society (AOFAS) scores were determined. GRF were measured using an instrumented treadmill. A two-way model of analysis of variance (ANOVA) was used to determine the effects of surgery on biomechanical parameters of walking, particularly propulsion. RESULTS: Epidemiological, radiographical and clinical data were comparable in the two groups and better restoration of propulsive function was found after osteotomy as shown by ANOVA (two way: surgery × foot) with a surgery effect on vertical forces (p < 0.01) and a foot effect on anteroposterior impulse (p = 0.01). CONCLUSION: Patients who underwent Scarf osteotomy had a gait pattern similar to that of their non-operated foot, whereas those who underwent arthrodesis of the first (metatarsophalangeal) MTP joint did not totally recover the propulsive forces of the forefoot. TAKE HOME MESSAGE: The main findings of this study were that after surgical correction for hallux valgus, patients who underwent scarf osteotomy had a gait pattern similar to that of their non-operated foot in terms of forefoot propulsive forces (Fz3, Iy2), whereas those who underwent arthrodesis of the first MTP joint had not. Cite this article: Bone Joint J 2016;98-B:641-6.

[Dual articulation retentive acetabular liners and wear: surface analysis of 40 retrieved polyethylene implants]. / Analyse de surface après explantation de 40 cupules rétentives en polyéthylène à double mobilité

PURPOSE OF THE STUDY: The original concept of dual articulation retentive liners has been implemented in routine clinical practice for total hip arthroplasty since 1976. The retentive liner improves stability and the dual mobility favors preservation of joint motion. In this study, we analyzed wear of the two concave and convex surfaces in 40 retrieved polyethylene implants in order to search for factors favoring wear. MATERIAL AND METHODS: Forty polyethylene inserts were examined. These implants had been removed after mean implantation of eight years. Mean patient age at implantation was 48 years. The inserts were removed because of prosthesis infection or mechanical failure. Macroscopic examination was followed by a surface analysis with direct measurement of alterations of the curvature radii. Internal concavity was measured in the three dimensions using a 4-mm stylus (BNH 706). External convexity was measured by lateral projection. The estimated error was +/- 5 microm for both measurement methods. Manufacturers' tolerances for these implants were approximately 50 microm. Linear and volumetric wear was determined by comparing the measured dimensions with the theoretical dimensions of new inserts. RESULTS: Macroscopically, all of the pieces studied had lost their initial striation on the convex surface; 40% of the pieces displayed visible wear of the retentive collar. Mean annual wear was 9 microm (SD 9microm) for the convex surface and 73 microm (SD 69 microm) for the concave surface. Mean total wear, taken as the sum of the wears on the convex and concave surfaces was 82 microm (SD 72 microm). Volumetric wear was 28.9 mm3/yr for the convex surface (SD 27.6) and 25.5 for the concave surface (SD 23.2) giving a mean annual total volumetric wear of 54.3 mm3/yr (SD 39.6). DISCUSSION: Total wear observed for these 40 dual articulation liners which had functioned in vivo was to the same order as reported for the metal-polyethylene bearing with 22.2 mm femoral heads. Considering the wear on both the convex and concave surface, the dual articulation was not associated with increased wear compared with the conventional metal-polyethylene bearings, but with the advantages of retention and greater stability. CONCLUSION: Use of a dual articulation acetabular liner is an attractive solution when a metal-polyethylene bearing is considered. The benefit in terms of joint stability does not increase wear.

Results of anatomic gracilis MPFL reconstruction with precise tensioning.

BACKGROUND: The medial patellofemoral ligament (MPFL) is the most commonly injured structure in patients with objective patellar instability. The objective of this study was to prospectively evaluate the clinical and radiographic results of MPFL reconstruction in 50 patients with chronic patellar instability. METHODS: Fifty patients with chronic patellar instability, aged 15-39 years, were included. The MPFL was reconstructed using a free gracilis autograft tendon. Two anchors were used for patellar fixation, and femoral fixation was achieved with an interference screw placed into a tunnel between the adductor tubercle and medial epicondyle. The graft was tensioned to 10 N with the knee in 30° flexion. IKDC and Kujala scores were assessed pre- and post-operatively. Patellar tilt was measured from CT scans with the quadriceps relaxed and contracted, both pre- and post-operatively. RESULTS: The follow-up period was 7 to 44 months (mean: 25 months, SD 10.3). The mean raw IKDC score increased from 51.5 preoperatively to 71.7 at last follow-up, the mean overall IKDC score increased from 38.5 to 61.7 and the Kujala score increased from 48.3 to 82.4. On CT scans, the mean patellar tilt went from 24° to 16.2° with the quadriceps relaxed and 27.7° to 18.1° in contraction. No recurrent dislocation was observed. CONCLUSION: This technique of MPFL reconstruction provided significant improvements in IKDC and Kujala scores and significant reduction in patellar tilt. No recurrent dislocations were observed during the study period.

Medial patellofemoral ligament reconstruction: clinical and radiographic results in a series of 90 cases.

INTRODUCTION: Among the numerous techniques available, medial patellofemoral ligament (MPFL) reconstruction is increasingly used for the surgical treatment of objective patellar instability. The main objective of the present study was to assess efficacy in preventing recurrence of patellar dislocation and in correcting radiographic patellar tilt. The study hypothesis was that MPFL reconstruction, isolated or with associated bone surgery, by restoring "favorable" graft anisometry, provides a good trade-off between patellar stability and absence of postoperative stiffness. MATERIALS AND METHODS: Eighty-seven patients (90 reconstructions) presenting with objective patellar instability were prospectively included. The standardized procedure comprised MPFL reconstruction using the gracilis tendon. Femoral fixation used an interference screw in a blind tunnel between the adductor magnus tubercle and the medial epicondyle; patellar fixation used 2 anchors. Complementary distal bone graft was associated in 21 patients due to a preoperative tibial tubercle-trochlear groove (TT-TG) distance exceeding 20mm or to patella alta. Functional IKDC and Kujala scores and radiographic measurement of patellar tilt and femoral tunnel position were assessed preoperatively and at end of follow-up. RESULTS: Mean follow-up was 24.3months (range, 6-49months). Three patients showed recurrence of patellar dislocation. Mean Kujala score rose from 53.88 preoperatively to 86.24 postoperatively, and mean real IKDC score from 45.15 to 73.92 (P<0.001). Patellar tilt decreased significantly between pre- and postoperative X-ray (P<0.001). DISCUSSION: MPFL gracilis reconstruction provides good clinical results and good radiologic correction of patellar tilt, making it a technique of choice in the treatment of objective patellar instability. LEVEL OF EVIDENCE: Level IV. Retrospective case series study.

[Long-term results of active-passive ligament repair of the external lateral ligament of the ankle]. / Résultats à long terme de la ligamentoplastie activo-passive du ligament latéral externe de la cheville.

We reviewed 95 ankles at an average of 9 years after an "activo-passive" operation performed for chronic lateral instability. All the patients had suffered recurrent ankle sprain or instability, with pain in 67 patients. Ten ankles showed a subtalar injury at operation. Degenerative changes were noted in 11 ankle joints. On review, 81 ankles (85%) were stable. The 14 cases with persistent instability had developed the problem one to five years after operation. Two cases presented with limitation in mobility. Osteoarthritis, found in 15 ankles, was severe in only two, and had been present on preoperative films. We found no correlation between functional results (talar tilt, anterior-drawer test) and radiological evaluation. The "activo-passive" operation provides long-term stabilization with preservation of the ankle and of subtalar mobility without severe osteoarthritis.

[Peroneal nerve entrapment syndrome of the front of the foot. Treatment by neurolysis. Apropos of a bilateral case]. / Le syndrome du nerf musculo-cutané au dos du pied. Guérison par neurolyse. A propos d'un cas bilatéral.

A case of bilateral entrapment of the superficial peroneal nerve at the anterior aspect of the ankle was seen in a 51 year old patient. After failure of the conservative treatment, surgical neurolysis resulted in complete relief.

[Wear characteristics of different metal-polyethylene beating surfaces. An experimental study of a new model of knee prosthesis]. / Caractéristiques d'usure de différents couples de frottement métal-polyéthylène. Etude expérimentale sur un nouveau modèle de prothèse de genou.

PURPOSE OF THE STUDY: Wear of artificial components joint is the most important factor in long term durability. Only few studies have analysed in laboratory experimentation the quality of different alloys on the same type of prosthesis. MATERIAL: During the development of a new knee prosthesis, we studied the friction mechanisms of the metal/polyethylene (UHMWPE) couple and particularly the value of titanium alloy (Ti-6AI-4V) treatment using an ionic nitrogen implantation process (IMPLATEC). Two friction surfaces were studied in vitro: one in flexion-extension between femoral component and tibial plateau, the other in rotation between tibial plateau and "metal-back". METHODS: The implanted Ti-6AI-4V was compared with 316L stainless steel, cobalt chromium molybdenium alloy and with Ti-6AI-4V using a prosthesis of each configuration. The samples were tested on a TRIBOCUP friction machine during 3 x 10(6) cycles in Ringer 's solution. The friction couples were controlled every 200,000 cycles and the loss of polyethylene mass every 500,000 cycles. We have also evaluated the roughness and the rubbing surface macroscopically. RESULTS: The results analysis shows that friction couples such as Cobalt Chromium and implanted Ti-6AI-4V are weakest but implanted Ti-6AI-4V over time, tends to match the strength of Ti-6AI-4V without treatment. With implanted Ti-6AI-4V and with Cobalt Chromium alloy, the loss of polyethylene is slight comparatively to the stainless steel and non implanted Ti-6AI-4V. Surface analysis showed good protection of titanium alloy by ionic implantation especially in the femoral component where roughness is close (0.04 micron) to that of Cobalt Chromium alloy (0.07 micron). DISCUSSION: Our study confirms the results with pin-on-disk and cup-on-ball with results for the Ti-6AI-4V implanted and Cobalt Chromium alloys with protection of the metal surface and decrease of polyethylene wear comparatively to stainless steel and non implanted Ti-6AI-4V. CONCLUSION: Our conclusion is for this type of experimental device that the surface condition is satisfactory for such friction couples as implanted Ti-6AI-4V/polyethylene and Cobalt-chromium/polyethylene, with very similar results. However, the long-term durability of the nitrogen implanted on Titanium Alloy remains unknown.

[Surgical treatment of ruptures of the Achilles tendon. Apropos of 42 cases treated by Bosworth's technique]. / Traitement chirurgical des ruptures du tendon d'Achille. A propos de 42 cas traités selon la technique de Bosworth.

PURPOSE OF THE STUDY: There is no consensus on the treatment of acute ruptures of the Achilles tendon. We have chosen surgical technique with early muscle stimulation. This study analyses possibilities of functional recovery and complications in Athletes. MATERIALS AND METHODS: Between 1983 and 1994, we treated surgically 42 Athletes who had Achilles tendon ruptures with early musculo-tendinous stimulation. The 39 male and 4 female patients had a mean age of 41 years (range, 15 to 70). We have always used Bosworth's technique with gastrocnemius flap procedure. Immediately after surgery, weightbearing with below-the-knee cast was initiated for 6 weeks followed by rehabilitation. RESULTS: There was no local major complication, deep vein thrombosis or pulmonary embolism. Only one patient suffered from a traumatic rerupture one month after surgery. Mean value of the calf atrophy was less than 1 cm. 93 per cent of patients returned to previous activity levels and 78.5 per cent of patients returned to their usual sport activity. DISCUSSION: Like this study recent results confirm the low complication and recurrence rate of the surgical treatment. Percutaneous technique and conservative treatments seem to be worse for rerupture and sportive functional recovery. Early muscle stimulation decrease morbidity and calf atrophy. Our protocol with weightbearing in ankle neutral position reduces calf atrophy. CONCLUSION: A rigid and stable reconstruction, allowing early weightbearing without equinus position seems to be a rational treatment for Achilles tendon rupture in athletes.

[Posterior dislocation of the hip associated with fracture of the neck of the femur. Apropos of 3 cases]. / Les luxations postérieures de la hanche associées à une fracture du "col" du fémur. A propos de 3 observations.

Three patients with posterior dislocation of hip associated with fracture of neck of femur were treated by early sanguineous reduction and osteosynthesis. This therapy was very effective since necrosis did not develop either in the short or long-term follow up (1, 3 and 4 years). These findings combined with documented data are in favor of anatomic reconstruction of upper end of femur by stable and solid osteosynthesis, at least in young adults. Early operation, an irreproachable operating tactic (orthopedic table, ventral decubitus, posterior approach), an immediate stable and solid synthesis and a deferred load bearing (beyond 6 months) should reduce the risk of femoral head necrosis to a minimum.

Dual mobility retentive acetabular liners and wear: surface analysis of 40 retrieved polyethylene implants.

PURPOSE OF THE STUDY: Dual mobility systems with retentive acetabular liners have been used in clinical practice for total hip arthroplasty since 1976. The dual mobility system preserves a wide range of motion while providing greater stability. This study measured wear on the concave and convex surfaces of 40 retrieved polyethylene liners, to evaluate the advantages of this system in relation to wear. MATERIAL AND METHODS: Forty polyethylene inserts that had been removed due to infection or mechanical failure after a mean 8 years were analyzed. The mean age of patients at arthroplasty was 46 years old. Macroscopic analysis was followed by surface analysis with direct measurement of changes in the curvature radii. The internal concave surface was measured in three dimensions using a 4-mm stylus (BNH 706). External convexity was measured by lateral projection. The estimated error was ± 5 µm for both measurement methods. Manufacturers' tolerance for these implants was approximately 50 µm. Linear wear and wear volume was determined by comparing the measured dimensions with the theoretical dimensions of new liners. RESULTS: Macroscopically, all of the pieces studied had lost the initial machined grooves on the convex surface; 40% of the pieces showed visible wear of the retentive collar. Mean annual convex surface wear was 9 µm (SD 9µm) and 73 µm (SD 69 µm) for the concave surface. Mean total wear, which was the sum of the wear on the convex and concave surfaces was 82 µm (SD 72 µm). Wear volume was 28.9 mm(3)/yr for the convex surface (SD 27.6) and 25.5 for the concave surface (SD 23.2) with a mean annual total wear volume of 54.3 mm(3)/yr (SD 39.6). DISCUSSION: Total wear in the 40 dual mobility liners that had functioned in vivo was similar to that reported in metal-polyethylene bearings with 22.2mm femoral heads. The results of wear in both the convex and concave surfaces show that wear with the dual mobility system was not increased compared to conventional metal-polyethylene bearings, while providing better retention and greater stability. CONCLUSION: The use of dual mobility acetabular liners is an attractive solution when a metal-polyethylene bearing is needed. The increased joint stability is not associated with increased wear.

Assessment of joint position sense deficit, muscular impairment and postural disorder following hemi-Castaing ankle ligamentoplasty.

INTRODUCTION: Hemi-Castaing ligamentoplasty is a treatment for chronic ankle instability, accused of weakening a powerful stabilizing muscle: the peroneus brevis. OBJECTIVES: To assess proprioceptive and muscular impairment following hemi-Castaing and impact on postural control. METHODOLOGY: A retrospective series of 21 patients underwent clinical (Karlsson, AOFAS) and proprioceptive assessment with isokinetic assessment (evertors and invertors) on a Con-Trex dynamometer and postural assessment on a Win-Posturo force platform, at a minimum 6 months postsurgery. RESULTS: At a mean 18 months' follow-up, mean Karlsson score was 84 and AOFAS score 88. Ankle joint position sense error was less on the operated than on the healthy side. Evertor strength deficit with respect to the healthy side was 4.7% (ns) at 30°/s and 5.7% (ns) at 120°/s in concentric mode and 6.6% (ns) in excentric mode. After surgery, the evertor/invertor ratio was >1 (in favor of the evertors). Postural values were significantly higher for the operated ankle. DISCUSSION-CONCLUSION: Hemi-Castaing ligamentoplasty provided excellent clinical and functional results. It did not disturb the agonist/antagonist balance of the ankle muscles, and harvesting a half peroneus brevis did not impair evertor isokinetic force. Joint position sense was not impaired; indeed, deficits with respect to the contralateral side showed improvement. LEVEL OF EVIDENCE: Retrospective study.

Multiscale analysis of anterior cruciate ruptures: Prospective study of 49 cases.

INTRODUCTION: Partial anterior cruciate ligament (ACL) ruptures are common. The ability to distinguish between various types of ACL ruptures preoperatively would allow surgeons to choose the most appropriate surgical treatment. HYPOTHESIS: A partial ACL rupture can be diagnosed preoperatively. MATERIAL AND METHODS: The goal of this single-center, prospective study was to establish correlations between various macroscopic types of ACL ruptures determined by arthroscopy with data from clinical examination, knee laxity measurements (GnRB(®)) and magnetic resonance imaging (MRI). The 49 patients included over a six-month period had a diagnosis of ACL rupture based on the clinical examination. Four arthroscopy categories were defined based on the French Arthroscopy Society (SFA) classification. Each patient had their knee laxity measured, a preoperative MRI performed and a clinical exam done in the operating room before the procedure. RESULTS: During arthroscopy, the ACL was described as "Complete tear" in 23 of 49 patients, "Healed onto PCL" in 12, "Posterolateral bundle preserved" in 14 and "Healed into notch" in none of the patients. The clinical exam alone could not discriminate between the various types of ruptures (P>0.05). With MRI, the sensitivity was 84% and the specificity was 92% for partial ACL rupture. There was a strong correlation between MRI and the various arthroscopy groups (P<0.05). There was a significant difference (P<0.05) between partial and complete ruptures in terms of knee laxity. CONCLUSION: This study helped define the relationships between arthroscopy findings, MRI findings and knee laxity measurements. It is feasible to make a preoperative diagnosis of partial ACL rupture. LEVEL OF EVIDENCE: Level IV, prospective cohort study.