Satisfactory long-term MRI after autologous chondrocyte implantation at the knee.

PURPOSE: Autologous chondrocyte implantation (ACI) to address isolated condylar lesions is supposed to limit degenerative deterioration in neutrally aligned knees. Here, we report long-term results of the first-generation ACI technique with periosteal flap. METHODS: Twelve patients, 29 years old on average, were included on the basis of pre-operative MRI selection of lesions >2 cm2. Cartilage carrots were harvested arthroscopically, then cultured and finally re-implanted within a mean time interval of 12 weeks. Ten-year MRI results were analysed according to a semi-quantitative scale, along with functional assessment based on International Knee Documentation Committee score, Lysholm et al. score and the Tegner et al. activity scale. RESULTS: One patient secondarily required valgus tibial osteotomy with mosaic plasty. Another incurred graft hypertrophy that necessitated arthroscopic peeling. MRI showed that cartilage repair filled more than 50% of the initial defect in 9 patients. Standard radiographs revealed slight narrowing of the joint line. Overall, functional scores improved durably by 50%, although activity level decreased substantially. CONCLUSION: ACI contained degenerative changes within moderate stages while maintaining durable functional improvement. However, in the absence of controls, it was difficult to differentiate between these findings and the spontaneous evolution of non-treated lesions. LEVEL OF EVIDENCE: Case series, Level IV.

[Superselective angiography of the circumflex arteries in preoperative evaluation of femoral neck fractures]. / L'angiographie supersélective des artéres circonflexes dans l'evaluation pré-opératoire des fractures du col fémoral.

The study of arterial vascularity in the head and neck of the femur is performed as an emergency exploration of femoral neck fractures by means of selective catheterization. The systematization of vascular lesions thus obtained is compared with the anatomical types of fractures. The posteromedial circumflex artery is not injured definitively as a rule, so that conservative osteosynthesis can be preferred to arthroplasty.

[Valgus fixation of trochanteric fractures in elderly patients. Early weight-bearing walking. Apropos of 25 cases]. / Valeur de la valgisation pour la mise en charge précoce des fractures trochantériennes du vieillard. A propos d'une série de 25 cas

The authors have treated 25 unstable trochanteric fractures in old people by valgus osteotomy and nail-plate fixation. In 6 cases a medial translation was added. Walking with weight bearing was started 7 to 14 days after the operation. The results were satisfactory in only 14 cases. The authors think that this type of fixation is logical on a bio-mechanical standpoint. However they conclude that the procedure is not fiable enough.

[Nailing according to Ender. Biomechanical study and results of 120 cases]. / L'enclourage selon Ender. Etude biomécanique et résultats à propos de 120 cas

The authors have conducted a clinical and biomechanical study of blind nailing of trochanteric fractures by the Ender's technique. The nail is introduced through the medial femoral condyle. The study was based on 120 operations. From the biomechanical standpoint, the authors studied the forces exerted in the medullary canal of the femoral shaft and the grip of the nail in the head and neck of the femur. In most of the cases the technique allowed immediate walking with weight-bearing. The results are compared with those obtained after nail-plate fixation. They were superior on three counts--less infection, less breakage of inserted material and less non-union, but the technique produced more mal-union. For this reason, the authors consider it to be an excellent technique but to be reserved for older patients.

[The use of sulphan blue dye during surgical procedures for bone infection]. / Coloration vitale au bleu de disulphine dans la cure chirurgicale de l'infection osseuse.

Sulfan blue is a vital dye which can be injected intravenously before a surgical procedure and produces a greenish coloration of all vascularised tissues. The authors describe the technique of its use and its toxicity. This technique makes it possible to recognize during an operation all devitalised tissues and to excise them with greater accuracy.

[Intramedullary nailing with reaming. A critical analysis of Kuntscher's principle (author's transl)]. / L'enclouage centro-médullaire avec alésage. Critique théorique et expérimentale des principes de Kuntscher.

The authors have reviewed two of Kuntscher's principles relating to intramedullary nailing: the moment of elasticity of the nail should be close to the moment of elasticity of the bone and the suppression of rotation movements at the fracture site is due to locking of the nail by virtue of its elasticity. They have conducted an experimental study which does not confirm these views. They considered that rotary stability is due to muscle tone, the line of the fracture and the anchorage of the ends of the nail at the upper and lower end of the bone.

[The mechanical properties of devices used for the fixation of femoral neck fractures (author's transl)]. / Aspects mécaniques de l'ostéosynthèse des fractures du col du fémur. Etude comprative des différents moyens d'ostéosynthèse.

The authors have studied the mechanical problems of internal fixation of femoral neck fractures, both from the theoretical and experimental point of view. They have tested stability of several types of fixation according to the obliquity of the fracture line. Three types of strain have been applied to fractured dried bone. Fixation by three parallel screws seemed to give the most stability. The authors conclude that, with this type of fixation, early weight-bearing can be resumed by patients with fractures of Pauwels type I and II, but weight-bearing is still dangerous in type III.

[Macroscopic, histologic and ultrastructural study of 89 prostheses of anterior cruciate ligament excised because of prosthesis failure]. / Etude macroscopique, histologique et ultrastructurale de 89 prothèses du ligament croisé antérieur explantées pour échec.

PURPOSE OF THE STUDY: This study concerns the etiology of failed synthetic anterior cruciate ligament (ACL) prostheses, and attempts to identify the primary mechanisms that lead to their premature rupture. MATERIAL AND METHODS: A total of 89 failed and surgically excised ACL prostheses were retrieved from young and active patients (27 +/- 7 years) at various orthopaedic centres in France. Their average duration of implantation was 34 +/- 24 months. They were examined macroscopically, histologically and by scanning electron microscopy (SEM) to determine the model, the manufacturer, the surgical technique used at implantation, the extent of healing, the site of rupture, as well as the morphology of the damage fibers. RESULTS: Seventy two of these explants represented 6 different models. While all 6 were fabricated from polyester fibres, each had a different textile construction, and each were associated with a unique healing and mechanical response in vivo. SEM observations confirmed that abrasion of the textile fibres were a phenomenon common to all models, and were the primary cause of prosthesis failure. Such wear zones were particularly prevalent at the exit of the tibial tunnel and around the femoral condyle. Collagenic infiltration into the synthetic ACL was poorly organized and unpredictable. It did not increase with the duration of implantation. In fact in certain models, it appeared to have caused deterioration and fraying of the textile structure rather than serving as a reinforcing matrix around the prosthesis. DISCUSSION: A synthetic ACL prosthesis is to be preferred for patients who do not have tissue available for autologous ligamentoplasty. Yet none of the synthetic devices examined in the present study were capable of stabilizing the knee over the long term. Among the factors that influenced their failure we found that the three most common mechanisms were flat abrasion against an osseous surface, flexural and rotational fatigue of the fibres, and loss of integrity of the textile structure due to unpredictable tissue infiltration during healing. CONCLUSION: The results of the present study show that none of the current models succeed in replacing the natural ACL. Future improvements may be achieved by developing surgical procedures for implantation combined with a prosthesis made from fibres and textile structures which are more abrasion resistant and promote predictable and controlled tissue infiltration.

[External rotational instability of the knee].

Among cases of recent or long-standing post-traumatic laxity of the knee ligaments, unstable lateral rotation is due to a well-defined anatomical lesion, viz. Rupture of the medial capsular ligament of the knee. This laxity is demonstrated clinically by the existence of an abnormal postero-anterior movement when the tibia is in lateral rotation. Its surgical treatment, suggested by D. Slocum, consists of displacement of the patella tendon. This rupture may exist alone but, usually, is associated with other ligamentous or meniscal lesions for which further specific treatment should be carried out. Slocum's operation has recently been used in the Strasburg Accident Centre. The early results are encouraging.