2015 ISAKOS Biennial Congress ePoster #1606

Long-Term Clinical Follow-Up of Arthroscopic Treatment of Symptomatic Discoid Lateral Meniscus in Children

Jonathan Haskel, BS, Piscataway, NJ UNITED STATES
Tyler Uppstrom, BA, New York, NY UNITED STATES
David M. Dare, MD, New York, NY UNITED STATES
Scott A. Rodeo, MD, New York, NY UNITED STATES
Daniel W. Green, MD, MS, New York, NY UNITED STATES
Hospital for Special Surgery, New York, NY, USA

FDA Status Not Applicable

Summary: Long-term clinical follow-up of patients who have undergone arthroscopic saucerization of discoid lateral meniscus demonstrates decreased clinical outcome scores, as well as increased incidence of pain, mechanical symptoms and functional limitations.

Abstract:

Background

The discoid meniscus, occurring almost exclusively on the lateral side, can lead to pain, popping, snapping, and decreased knee extension. Current treatment of a symptomatic discoid lateral meniscus involves arthroscopic partial meniscectomy to reshape the meniscus (saucerization), in conjunction with repair of any detached or peripherally unstable fragment. While we have shown good short-term outcomes in a previously published study conducted at our institution, the purpose of this study was to examine the long-term clinical outcomes of arthroscopic partial meniscectomy for the treatment of discoid lateral meniscus in children.

Methods

Twenty-seven consecutive patients that underwent arthroscopic meniscal saucerization by one of two surgeons at a major academic medical center between 1997 and 2002 were previously identified in a study published out of this institution. These patients were included in this study if they were willing and able to complete the 5 outcomes questionnaires (IKDC Subjective Knee Evaluation, Kujala Scoring Questionnaire, Lysholm Knee Scoring Scale, Marx Activity Rating Scale and Tegner Activity Scale). Seven additional patients that were treated consecutively at least 10 years ago were also included in the study. Patients were also given the opportunity to receive a knee exam performed by one of the two treating surgeons. The exam was documented as per the IKDC knee examination protocol. Associations between outcome scores and discoid type, meniscal stability, location of instability, and age at time of surgery were identified.

Results

Of the 34 eligible patients (23 female, 11 male), 22 patients were contacted, and 21 agreed to participate. The average length of follow-up was 13.7 years, ranging from 10.3 years to 16.6 years. Average age at the time of surgery was 9.3 years. Long-term follow-up revealed average IKDC, Kujala, and Lysholm scores of 82.87, 86.63 and 83.73, respectively. Additionally, average Marx and Tegner scores were 5.36 and 5.63, respectively. Stratifying the Lysholm scores revealed outcomes that were 45.4% excellent, 18.2% good, 27.3% fair, and 9.1% poor. The average IKDC Knee Examination score was A (normal). One patient with especially poor outcome scores underwent two additional procedures after the index operation: arthroscopic debridement of the knee joint, followed by meniscal allograft transplantation. In total, 20.6% (7 of 34) of eligible patients underwent a subsequent surgical procedure on the affected knee.

Conclusions

Numerous studies have demonstrated good to excellent short-term outcomes after arthroscopic treatment of discoid meniscus. At an average follow-up of nearly 14 years, our data suggests that clinical outcome scores decline over time. Compared to our previous study with 2-year follow-up, there is an increased incidence of knee pain, mechanical symptoms, and functional limitations. Despite excellent post-operative IKDC examination scores, approximately 40% of our patient cohort demonstrated relatively low Lysholm scores (fair and poor). The overall modest results demonstrate the challenging clinical problem of lateral meniscus injury in young active patients, and illustrate the need for further solutions for meniscus repair or replacement.