Introduction

Currently, a validate scale of ankle osteoarthritis (OA) is not available and different classifications have been used, making comparisons between studies difficult. In other joints as the hip and knee, the Kellgren-Lawrence (K&L) scale, chosen as reference by the World Health Organizations is widely used to characterize OA. It consists of a physician based assessment of 3 radiological features: osteophyte formation, joint space narrowing and bone end sclerosis described as follows: grade 0: normal joint; grade 1: minute osteophytes of doubtfull significance; grade 2: definite osteophytes; grade 3: moderate diminution of joint space; grade 4: joint space greatly impaired, subchondral sclerosis. Until now, the K&L scale has never been validated in the ankle. Our objective was to assess the usefulness of the K&L scale for the ankle joint, by determining its reliability and by comparing it to functional scores and to computerized minimal joint space width (minJSW) and sclerosis measurements. Additionally we propose an atlas of standardized radiographs for each of the K&L grades in the ankle.

Introduction

Among patients with ankle osteoarthritis (OA) a post-traumatic origin is much more frequent than among those with knee or hip OA. However, long-term studies evaluating risk factors for the development of OA after ankle fractures are lacking.

Introduction: An ankle fracture represents the most frequent osseous injury in both the elderly and non-elderly population. To date, only a limited number of retrospective studies have addressed medium-term outcome following ankle Open Reduction and Internal Fixation (ORIF). The purpose of this study was to assess residual pain and functional outcome 10 to 20 years after operative treatment of ankle fractures and to evaluate the incidence of symptomatic and radiographic ankle osteoarthritis (OA).

Methods: We designed a retrospective study including all consecutive patients who underwent ankle ORIF between January 1988 and December 1997 in a University Hospital setting. Pilon and talus fracture as well as pediatric patients were excluded. Patients were seen by two senior residents 10–20 years after their index surgery. Residual pain was measured using the Visual Analog pain Scale. Function and general health status were assessed using the Olerud and Molander Ankle Score, the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score and the 12-item short-form health survey (SF-12). Ankle OA on standard radiographs was scored according to the revised Kellgren and Lawrence (K& L) scale.

Results: 374 patients (56% men) underwent ankle surgery during the defined period. 10% of the patients had a Weber A fracture, 57% a Weber B and 33% a Weber C fracture. Mean age at the time of operation was 42.9 years (+/− 17.1; range 16–86 years). 10–20 years after surgery, 47 patients had died, 126 had left the country and were lost to follow-up, 99 did not respond or refused to participate, and 102 patients were seen at the follow-up visit. These patients did not differ in terms of age, gender distribution, BMI and type of fracture from those who were not seen. The mean duration of follow up was 17.3 years (+/− 3.3). Advanced radiographic OA (K& L grade 3 and 4) was present in 34.3 % of the patients. Symptomatic OA was reported by 34.3 % of the patients (AOFAS pain score < 40). Both clinically symptomatic and radiographic ankle OA was found in 18 patients (17.6%). Function was good in 85% of the cases (total AOFAS hindfoot score between 80 and 100 points; mean total AOFAS hindfoot score 89.9, +/−14.6). The mean Olerud and Molander ankle score was 86.5 (+/−18.7). The general health status (SF-12) was similar to representative values of the general population with a similar mean age.

Conclusion: 10–20 years after operative treatment of an ankle fracture, the incidence of advanced radiographic post-traumatic ankle OA was 35%, symptomatic OA was present in one third of the patients and about one fifth had both. The majority of the patients reported good function.