Difficulties arise when counselling younger patients on the long-term sequelae of a minor knee chondral defect. This study assesses the natural history of patients with grade 2 Outerbridge chondral injuries of the medial femoral condyle at arthroscopy. We reviewed all arthroscopies performed by one surgeon over 12 years with Outerbridge grade 2 chondral defects. Patients aged 30 to 59 were included. Meniscal injuries found were treated with partial menisectomy. All patients had five-year follow up minimum. Primary outcome measure was further interventions of total or unicondylar arthroplasty or high tibial osteotomy. We analysed 3,344 arthroscopies. Average follow up was 10 years (Range 5–17 years). A total of 357 patients met inclusion criteria of which 86 had isolated medial femoral condyle disease. Average age was 50 at the time of arthroscopy. Average BMI at surgery was 31.7 and average chondral defect area was 450 mm². Isolated MFC chondral disease had a 10.5% intervention rate. Intervention occurred at a mean of 8.5 years post primary arthroscopy. In young patients Outerbridge II chondral injuries affecting ≥2 compartments have a high rate of further intervention within a decade. This information is crucial in counselling young patients on long-term sequelae of benign chondral lesions.

Introduction

It is now widely accepted that acute knee dislocations should be managed operatively. Most published studies are from outside the UK and from major trauma or specialist centres. The aim of the study is to report the functional outcomes of all patients presenting with an acute knee dislocation at our institution all of whom were surgically managed. The results were then compared to other published series. The hypothesis being that there would be no significant difference in the functional outcome scores between the groups.