Knee Pain: Pain Patterns of Myofascial Pain Syndrome and Degenerative Arthritis

ABSTRACT

OBJECTIVE: To evaluate the pain patterns of patients with osteoarthritis (OA) of the knee. METHOD: Forty-four patients (mean age 56.1 years) with pain around the knee who met the Simons' criteria for myofascial pain syndrome (MPS). Patients drew in their pain areas on a pain drawing diagram. The pain areas were input into the Pain Chart System (PCS) software program for analysis. Physical examination, trigger point injection, and exercises for knee muscles were performed. Oral analgesics were not prescribed. RESULTS: MPS was clinically diagnosed in all 44 patients. Radiologic examination revealed degenerative changes in 49 knees. Pain patterns detected by the PCS revealed pain patterns compatible with myofascial trigger point in the vastus medialis in 37 cases, rectus femoris in 32 cases, adductor longus in 5 cases, sartorius in 2 cases, vastus lateralis in 1 case, and the popliteus in 1 case. Following treatment, 36 of the 44 patients experienced pain relief. CONCLUSION: Degenerative changes of the joint seem not to be cause of the knee joint pain. Instead, pain relief following MPS treatment indicates the cause of knee pain as MPS. We recommend that the first step in the treatment for knee pain include recognition and treatment of MPS before applying invasive treatment.