Bilateral knee anteroposterior radiograph
Repeat anteroposterior radiograph
A 58-year-old woman presents with left knee pain for several months. She had a left knee arthroscopic lateral meniscectomy 10 years ago. Bilateral knee anteroposterior radiograph (Figure 1) taken 5 years ago showed moderate lateral joint line osteoarthritis. Repeat anteroposterior radiograph (Figure 2) shows that her arthritis has progressed significantly in the lateral compartment of the left knee.
This case has been brought to you in partnership with the Journal of Orthopedics for Physician Assistants.
This article originally appeared here.
Submit your diagnosis to see full explanation.
Arthroscopic meniscectomy is one of the most common surgical procedures performed in orthopedic practice. The primary function of the medial and lateral meniscus is shock absorption to protect the cartilage of the knee joint. The menisci transmit 50% of the weight-bearing load in extension and 85% in flexion. Even small changes to the meniscus, including a partial meniscectomy, can dramatically alter the biomechanics of the knee.1
There is now a strong push to repair meniscus tears whenever possible as arthroscopic meniscectomy is a known risk factor for the development of knee osteoarthritis. Arthroscopic meniscectomy patients often develop long-term pain and functional limitations. In patients who require meniscectomy, the smallest amount of torn meniscus tissue as possible is removed until a stable rim of tissue remains. The amount of tissue removed is directly proportional with the amount of arthritis likely to develop years later. The amount of meniscal tissue removed is the strongest predictor of long-term onset of arthritis. Other risk factors that have shown a higher rate of knee osteoarthritis after arthroscopic meniscectomy include obesity, female gender, genetic predisposition, simultaneous ACL deficiency, and advanced age and cartilage wear at the time of surgery.2
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor-in-chief of the Journal of Orthopedics for Physician Assistants (JOPA).
Watts E, Karadsheh E. Knee osteoarthritis. Available at: https://www.orthobullets.com/recon/12287/knee-osteoarthritis
Papalia R, Del Buono A, Osti L, Denaro V, Maffulli N. Meniscectomy as a risk factor for knee osteoarthritis: a systematic review. Br Med Bull. 2011;99:89-106.