[Intraarticular lesions associated with tibial fixation during anterior cruciate ligament reconstruction]

Anterior cruciate ligament reconstruction is a demanding procedure; complications may arise at any of its stages. This is the report of three cases in which the tibial fixation devices (IntraFix and Bio-IntraFix) led to intraarticular lesions. The complications were detected in one of the cases while the patient was still in the operating room and in the remaining two during the follow-up. All the patients had a stable knee, but all of them sustained chondral lesions resulting from the inadequate placement of the implants used for tibial fixation. Several suggestions to avoid the complications stemming from these devices are provided.

[Total femoral replacement. Three case reports and literature review]

INTRODUCTION

Currently hip and knee joint replacement were performed frequently at orthopedic centers. However, these surgeries do not last forever and thus revision procedures are required. The latter usually involve complications like bone loss that may compromise implant stability.

METHODS

Three hip and knee arthroplasty revisions were performed from 2006 to 2011, which warranted the total replacement of the femur and the joints involved. The purpose of this paper is to describe our experience with these implants used in arthroplasty revision surgery.

RESULTS

A standardized postoperative management protocol was used in all patients. They required debridement and specific antibiotic therapy. They had a significant improvement in the pain visual analog scale (VAS) (the score went from 8 to 2.3, p ‹ 0.05) and in function, measured with the WOMAC score (from a preoperative score of 21.6 to 55, p ‹ 0.05).

CONCLUSIONS

Total femoral replacement is an infrequent, demanding and complex salvage surgery that represents an alternative to the disarticulation of the pelvic limb at the end stage of prosthetic disease. This is a feasible option used to improve patient functionality and decrease residual capacity for performing activities independently.

Animal model of acute gout reproduces the inflammatory and ultrasonographic joint changes of human gout

INTRODUCTION

Gout is an inflammatory condition induced by the deposition of monosodium urate (MSU) crystals in the joints and soft tissues that can produce acute or chronic arthritis. Several animal models of crystal-induced inflammation have been proposed that involve direct injection of MSU-crystals into different anatomical structures; however, only a few of these models reflect a true diarthrodial joint microenvironment in which an acute gouty attack takes place. The aim of this study was to assess the inflammatory and structural joint changes in a rabbit model of acute gout attack by ultrasound (US), synovial fluid (SF) and histopathological analyses.

METHODS

Under US guidance, 42 rabbit knees were randomly injected with a suspension of 50 mg/ml of either MSU or allopurinol synthetic crystals. The control group received intra-articular vehicle of phosphate-buffered saline (PBS). US evaluation, SF and histopathological analyses were performed at days 1, 3, and 7.

RESULTS

A total of 21 rabbit knees were assigned to the control group, 12 to the MSU-crystals group, and 9 to the allopurinol crystals group. By US, the MSU crystals group displayed the double contour sign and bright stippled aggregates in 67% and 75% of joints, respectively. Neither control knees nor allopurinol crystals group displayed these US signs. Power Doppler (PD) signal was moderate to intense in the MSU-crystals group and greater than both the allopurinol crystal and control groups at day 1 (P<0.001) and 3 (P<0.05), with its practical disappearance by day 7. SF leukocyte count was 40,312±6,369 cells/mm3 in the MSU-crystals group, higher than in controls (P=0.004) and allopurinol crystal group (P=0.006). At day 7, SF leukocyte count decreased in both MSU and allopurinol crystal groups reaching the non-inflammatory range. Histologically, at day 3 intense synovial polymorphonuclear cells infiltration and MSU aggregates were identified.

CONCLUSION

The rabbit model of MSU crystal-induced acute arthritis efficiently reproduces the inflammatory, US, SF and histopathological changes of the human acute gouty attack.