MENISCAL TEARS: EPIDEMIOLOGY AND CORRELATION BETWEEN CLINICAL AND ARTHROSCOPIC FINDINGS

Abstract

Background: Arthroscopic menisectomy is one of the most commonly performed procedures in the NHS, yet there is no recent review of contemporary knee arthroscopy for meniscal tears or comparisons of tear morphology and clinical findings. We aim to address this problem with a large, prospective longitudinal study.

Aims: The aims of this study were to examine the anatomical location and morphology of meniscal tears encountered at arthroscopy and to correlate this to the clinical findings.

Method: Data on 775 consecutive patients undergoing knee arthroscopy by a single surgeon between 1994 and 2004 was prospectively collected. Clinical data included age, sex, history of trauma, joint line tenderness and presence of an effusion. Meniscal tears were arthroscopically classified by site (medial/lateral, anterior/middle/posterior) and type (flap, horizontal cleavage, bucket-handle, radial, degenerative and other).

Results: Data was complete for 724 patients (517 male and 207 female [m:f 2.5:1]). The mean age was 48 years (range 10 to 87 years). Mean duration of symptoms was 8 months.

54% of meniscal tears were medial, 12% lateral and 10% bilateral. Patients with a lateral tear were significantly younger (45 Vs 51 yrs, p< 0.001).

The most common type of medial tear was a flap tear (34%), followed by horizontal cleavage tears [HCT] (18%). The posterior 1/3 is the most common position. Laterally the tear morphology shows HCT comprising 25% and degenerative tears 17%, with the most common position a middle 1/3 tear. Lateral tears are more common in females (p< 0.05)

Patients with bucket handle tears were significantly younger (41 Vs 53yrs, p< 0.001) and more likely to have a history of trauma (p< 0.001). Medial joint line tenderness was the most sensitive test (79%) and had the highest positive predictive value (81%). McMurry’s test is the most specific for both medial and lateral tears (90%) but is not sensitive. Medial meniscal tears are more accurately diagnosed clinically than lateral (79% Vs 50%).

Conclusion: Meniscal tears are a common pathology, particularly on the medial side. Morphology and position of tears vary as to which side the tear is. Clinical details can help determine the type of tear found with clinical examination being more accurate for medial meniscal tears.