Aim of the study was to evaluate the recovery and short term results of simultaneous bilateral unicompartmental knee replacement in front of unilateral procedure.

Materials and methods: At the “Istituto Ortopedico Galeazzi”, in Milan, we performed 244 UKR in a 12 months period. Forty were sequential bilateral procedure. We compared two groups of patients: one bilateral sequential procedure (BPS), the other unilateral procedure (UP). Student t test has been used for statistical analysis.

Results: Blood transfusion: BSP 8 cases, and UP 5 cases. 90° active flexion: BSP 4,7 (2–6) days, and UP 3,5 (1–6) days. Stairs climbing: BSP 5,6 (4–8) days, and UP 4,9 (4–9) days. Hospital stay: BSP 12,4 (10–17) days, and UP 11,4 (5–19) days; p=0,045. Complications during the first month after surgery: BSP none, and UP 3 (1 wound redness, 2 urinary infection). From 6 to 18 months, KSS and function: BSP 53 (28–80) points, 61 (20–100) points; UP 51 (25–85) points, 66 (20–100) points; p=0,325 e p=0,133. Oxford self assessment were: BPS 26,57 and UP 23,54. No statistically significant differences were among groups.

Conclusions: This study shows bilateral procedure is safe, and allows recovery comparable to single knee procedure. Bilateral sequential unicompartmental procedure should be considered for bilateral arthritis of the knee.

Acquired pilon deformities are often a combination of axial deviation, translation, rotational defects and leg length discrepancy. Correction of a deformity pattern with a percutaneous rectilinear supramalleolar osteotomy and an external fixation by Ilizarov apparatus aims to reduce misalignment progressively, simultaneously and minimally invasively.

From 1994 to 2004, 27 patients were treated for pilon tri-planar deformity of the leg. The mean age was 27 years (range 16 to 49 years); 15 were males and 12 females. Type and level of the deformity were determined by preoperative X-rays. For the procedure, two rings of Ilizarov apparatus are positioned in the segment of the limb proximal to the osteotomy: one at the level of the proximal tibial metaphysis and the other 3–4 cm beyond the osteotomy. A third ring is positioned at the level of the tibial pilon, parallel to the articular edge of the ankle. In order to maintain stability of the ankle, a half ring or horseshoeshaped component should be placed on the calcaneus and metatarsals with opposing olive wires. The positions of the mobile joints between the rings depend on the location of the correction axis. Closed metaphyseal osteotomy is performed in order to correct tri-planar deformities in a progressive way, through angulations and translation in an oblique plane. The half ring on the foot maintains distraction in the ankle, which is necessary to reduce articular compression and to avoid soft tissue damage and muscular contractures in this region.

In all cases we achieved correction of the angular or rotational deformities. Bleeding was never over 100 ml. We have not observed any soft tissue damage. Controlled weight-bearing was practised on the first day postoperatively, and the mean hospitalisation time was 4 days. Time required to reach the correction was in a range of 3–6 weeks. In 20 patients the total leg discrepancy was in a range of 1.5–6 cm. We reported no case of infection nor union. The devices were removed after a mean time of 11 weeks (range 8–15 weeks). Corrections of tri-planar deformity of the pilon by the Ilizarov apparatus are progressive and minimally invasive. In addition, it is possible to treat misalignment and lengthening by a single operation. With the apparatus layout combining foot fixation and ankle distraction soft tissue and secondary deformities can be corrected and finally a rapid recovery of weight bearing is possible.

Aim: Endpoints that are more common than revision would be more valuable in survival analysis. Assessment of unicompartmental knee replacement (UKR) by patientñs own evaluation may be sensitive as for total knee replacement (TKR). Cohort of patients treated by UKR has been studied for satisfaction and pain as endpoints and related to TKR. Materials: At the Centro di Chirurgia Protesica, Istituto Ortopedico ÒGaleazziÒ, Milano (I), more than 600 hip and knee replacements are performed per year. Among these, from February to April 2001, 109 patients have been treated for primary unilateral arthritis of the knee by the same surgeon, same OR team, and environmental conditions. 53 patients received unicompartmental knee replacement (Allegretto TM, Centerpulse) because of unicompartmental knee degeneration. 56 patients received total knee replacement (Innex TM, Centerpulse) for tri-compartmental arthritis. Patients have been preoperative evaluated for age, ASA score, KSS and Function. Postoperative recovery and physio funtions. At 18 months follow-up, cohort of UKR has been evaluated for satisfaction and pain as endpoints by telephone interview. The same has been for TKR group. Results: No differences were between the UKR and TKR cohorts for age at surgery (UKR: 68yrs, 86-45; TKR: 69yrs, 83-51); ASA score, KKS (UKR: 54,2pts, 76-25; TKR: 43,3pts, 75-10); function (UKR: 67,5pts, 95-20; TKR: 60,6pts, 95-10). No differences were for recovery period and rehabilitation program. Within the TKR group had 1 died for post op cardiopulmonary complication. At follow-up patients was judged by the author not eligible for any revision, on clinical and radiological examination. None was lost at follow-up, none revised. At 18 months follow-up, UKR cohort, 52 on 53 patients were satisþed by their knee, event rate 98% (89–100). 18 on 52 were in mild pain and drug use, event rate 34% (28–39), 4 of those in trouble with stairs. 1 patient was not satisþed. For TKR cohort, 49 on 55 patients were satisþed, event rate 89% (81–97). 24 on 49 reported pain and drug use, event rate 49% (42–56), 7 of those in stairs climb limits. 6 patients were not satisþed. Conclusion: Because of long time is needed to produce adequate number in joint replacement groups, statistical method relies on survivorship analysis for studying adverse events. However confounding factors, lost of follow-up, and revision as endpoint may mislead results (Murray DW. et al. JBJS 1993). Meanwhile, randomised clinical trial provides a cornerstone not only for evidence-based medicine but also for evidence public health, evidence based hospital administration, evidence based purchasing, and evidence based consumerism (Sackett DL et al. BMJ 1994).

Our TKR cohort pain endpoint survival rate is comparable with others in literature (Murray DW, Frost SJD. JBJS 1998). Comparing TKR with UKR groups has limitation and EBM is not eligible for such groups. However, cohort study for joint replacement, performed within a short period of time, and less confounding factors, increases assessment reliability and endpoints deþ nition. Overall, our result shows lower pain and higher satisfaction events rate for UKR than TKR.