Purpose of the study: The objectives of this study were to measure tension force usually applied to the transplant and analyze its impact on postoperative laxity and joint mobility.

Material and methods: This was a prospective consecutive study. Inclusion criteria were: isolated tear of the anterior cruciate ligament (ACL) more than three months earlier, healthy contralateral knee, radiological anterior drawer measurements (Telos 20 kg) both pre and postoperatively, follow-up greater than six months. ACL reconstruction was achieved with a free bone-tendon-bone patellar transplant using the blind technique. A dynometer was used to measure the traction force applied by the operator using the «usual» method for the tibial fixation. The force applied (2, 4, 6, 9, or 11 kg) was recorded by the assistant and was maintained constant while screwing. Variables studied were: tension force applied to the transplant by four different operators, mobility of the two knees, differential laxity pre and postoperatively (L0 and L1) and relative gain in laxity (real gain/ideal gain).

Results: The study included 22 patients, mean age 26 years. Mean tension force applied was 7.68 kg and varied from 7.3 to 8.1 for each operator. Mean extension and flexion deficit compared with the healthy side was 1.6° and 3° respectively. There was no correlation between loss of mobility and tension applied. Mean laxities (L0 and L1) were 9.2 and 5.4 mm respectively. Mean minimal differential laxity (< 5 mm) was obtained for tension forces of 4 to 6 kg. There was no correlation between tension and L1. The relative gain was greater in the knees with tension at 6 kg. But there was no correlation between these two variables.

Discussion: This study provides the only available data on tension forces applied in routine practice. This tension does not appear to have an impact on the final joint mobility. It would appear however tht laxity would be minimal for tension forces to the order of 7 kg. These data are in agreement with reported in the literature were it is recommended to apply tension to the order of 1.5 to 7 kg.

Conclusion: It would not appear that measuring the force applied to the implant during the tibial fixation provides useful information for routine practice. The force applied in routine practice appears to give the best gain in stability without limiting joint mobility.

Purpose: The vast majority of forefoot infectious in neuropathy patients are plantar ulcers in diabetics. When conservative treatment is unsuccessful, radical treatment may be indicated, but correct choice of the amputation level is essential. The purpose of this work was to evaluate outcome after tibiocalcaneal arthrodesis achieved with an Ilizarof fixator.

Material and methods: The procedure was performed in nine patients between 1991 and 2002. Male gender predominated (seven men). Mean age was 65 years. Eight patients had diabetes and seven of them had complicated mal perforant. Two patients had bilateral involvement so a total of eleven arthrodeses were performed. The procedure began with de-articulation of the Chopard space and talectomy. After high section of the lateral maleolus, the tibia was cut flush with the joint. The calcaneal cut was vertical passing just behind the tarsal sinus. After verticalising the calcaneum, the two cut surfaces were joined. Arthrodesis was maintained with a circular Ilizarof fixator using two rings on the tibia and one on the calcaneum.

Results: At mean 20 months, we reviewed ten arthrodeses. Good results were obtained for seven and failure was observed in three (necrosis = 2 and severe suppuration = 1). All these problems resolved and fusion was achieved at five months on average. The type of diabetes, renal failure, duration of the infection, presence of severe contralateral lesions, and type of germ involved appeared to affect outcome.

Discussion: Alternatives to the Pirogoff procedure include Chopard amputation, with or without subtalar arthrodesis, and Syme amputation. The technique used in this cohort offers several advantages. The circular external fixator avoids the classic cross screwing in an infectious setting. The mechanical properties of the Ilizarof fixator favour healing and bone fusion. Finally, vericalisation of the calcaneum produces a longer stump so excessively anterior cicatrisation, which can be bothersome for the orthesis, is avoided

Conclusion: This surgical technique provides a radical treatment for proximal osteoarticular infections of the forefoot, often observed in diabetics. Indications are exceptional and should be reserved for lesions which are inaccessible to transmetatarsal amputation. The arthrodesis cannot be achieved without healthy talar stock. The procedure produces a long stable stump which is painless and easy to fit.