After catastrophic failure of first generation, joint replacement as treatment option for ankle osteoarthritis is undergoing a revival with improved second generation designs. Short to mid-term results reportedly equal those of ankle arthrodesis in terms of complications and revision, but preserving joint motion and protecting neighbouring midfoot joints from overuse and consecutive osteoarthritis. However, most reports derive from developers centres excluding the learning curve. We present clinical results and subjective outcome of an initial patient series undergoing ankle replacement in an independent centre.

From January 2004 to January 2008 a Hintegra^® prosthesis was implanted in 39 consecutive patients (41 ankles), average age 60.7 years (range 36.6–85.0), 13 males and 25 females. Repeated clinical follow up was done for an average of 2.2 years (range 0.5–4.3). All patients whose operation had been more than 0.7 years before were sent the FAOS (Foot and Ankle Outcome Score) in order to record the subjective outcome. Pre-operative diagnoses were posttraumatic osteoarthritis in 26 cases (63.4%), primary osteoarthritis in 9 cases (22%) and rheumatoid arthritis in 6 cases (14.6%).

Clinical examination did not show significant improvement of mean range of motion, dorsiflexion and plantarflexion compared with the preoperative status. The change in motion highly correlated with the preoperative mobility (r=0,8; p< 0.001): patients with the largest preoperative range of motion were the ones to lose most mobility, whereas patients with low preoperative motion gained mobility. About 60% of the patients achieved 25° to 30° total range of motion regardless of their preoperative mobility. Early postoperative complications occurred in 14 patients (34.1%). In all five subclasses of the FAOS a significant improvement was achieved within the observation period. Reduction of pain had the greatest impact on the improvement of quality of life, whereas change in mobility did not have any influence.

Joint replacement is a valuable treatment option for ankle osteoarthritis. There are however a series of early complications and restrictions of subjective outcome a surgeon has to be aware of when selecting an individual patient for ankle replacement. Further studies are needed to detect in which cases arthrodesis or prosthesis is preferable.

The implementation of standards for deformity correction planning of axial deformities and leg length discrepancy in paediatric orthopaedics and posttraumatic cases have improved the results of postoperative alignment and joint orientation. A variety of externally and internally applicable devices have been developed for limb lengthening and deformity correction. One of the most recent developments is the Taylor Spatial Frame Fixator based on a hexapod system and a computer software for deformity correction. But little is published about clinical results using this sophisticated technique and its possible advantages over other traditional unilateral fixators or ring systems. In times of difficulties financing our health care systems, a surgeons choice for a comparatively costly system should be based on qualified data. The aim of the present study was to compare the results of deformity correction and limb lengthening using a Taylor Spatial Frame with those of other ring fixators or unilateral systems.

Between 1996 and 2004, 72 deformity corrections and/or limb lenghtenings have been performed on 52 patients with the unilateral Orthofix system (n=32), the Ilizarov system (n=22) and the TSF device (n=18). Statistical analysis showed a direct correlation between the healing index and the age at operation, as well as between the lengthening distance and the rate of complications. There were no significant differences of the healing index between all three fixators and the number of complications between the Ilizarov and TSF device, but the unilateral Orthofix fixator showed significantly more axial deviations during distraction osteogenesis.

The Taylor Spatial Frame is easier to handle than the Ilizarov fixator but did not show superior results in clinical use.