LEG PAIN ??? RUNNING

Abstract

HISTORY A 45-year-old male presented to the clinic with right knee pain six weeks prior to running a marathon. He first noticed the pain six days prior to the visit when he was running down a hill and felt a sudden pop and sharp pain over his medial right knee as he stopped for water. The pain prevented him from continuing his run. After resting for two days, he was able to resume exercise using a Nordic Trac but was unable to return to running secondary to pain. He described the pain as “stabbing” and rated it 3–8/10; it only occurred with running. The pain was located over the medial aspect of his knee and did not radiate. He denied any associated swelling, locking, or giving way. He denied numbness and tingling. Ice and ibuprofen provided minimal relief. After a three-week course of rest and physical therapy, the patient experienced slight improvement of pain and was able to resume training with reduced discomfort. A diagnostic injection of lidocaine and bupivacaine into the pes anserine bursa upon follow-up provided immediate relief of the patient's symptoms. A dexamethasone injection was therefore performed one week prior to the marathon and enabled the patient to complete the race, with symptoms arising only after the 18-mile mark. After the marathon, the patient complained of the same medially-located pain but was now experiencing symptoms with walking. PHYSICAL EXAMINATION Inspection revealed no joint deformity, soft tissue swelling, ecchymosis, or effusion. Palpation consistently revealed tenderness inferior to the joint line on the anteromedial aspect of his right knee at the pes anserine bursa. He also had mild tenderness at the medial tibial plateau. He was non-tender over the lateral aspect of the knee, lateral tibial plateau, and tibial shaft. He had no joint line tenderness. The knee ligaments were stable to clinical examination. His patellar examination was unremarkable, and the quadriceps inhibition test was negative. He had full range of motion and strength with hip and leg movements but did experience pain over the pes anserine bursa with resisted right sartorius contraction. DIFFERENTIAL DIAGNOSIS Pes Anserine Bursitis. Medial Tibial Stress Syndrome (“shin splints”) Medial Tibial Plateau Stress Fracture. Knee osteoarthritis Patellar Tendinitis. Hamstring/Sartorius Tendinitis TESTS AND RESULTS Right Knee Radiographs, initial presentation (9–3–02) minimal medial compartment narrowing of the knees bilaterally questionable periosteal reaction at medial tibial plateau Right Knee MRI, initial presentation (9–4–02) bone edema at anterior portion of lateral tibial plateau soft tissue edema at anterior proximal tibia small joint effusion Right Knee Radiographs, post-marathon (10–7–02) indistinct area of bony destruction/resorption along medial posterior portion of the tibial metadiaphysis Right Tibia & Fibula MRI, post- marathon (10–9–02) persistent hyperintensity of the proximal tibia along the medial and lateral aspects posterior tibial diaphyseal stress fracture FINAL/WORKING DIAGNOSIS Pes Anserine Bursitis. Proximal Posterior Tibial Shaft Stress Fracture TREATMENT AND OUTCOMES 1. Physical Therapy: Stretching exercises and iontophoresis provided the patient with enough pain relief to enable him to return to a decreased level of running. 3. Diagnostic lidocaine/bupivacaine injection into the pes anserine bursa provided immediate relief of tenderness to palpation and pain with resisted sartorius contraction. The patient reported running pain-free several hours after the injection. 4. Therapeutic lidocaine/dexamethasone injection into the pes anserine bursa provided approximately 90% relief of symptoms for one week. This injection allowed the patient to complete his marathon training, as well as the race despite the onset of pain at mile 18. 5. Post-marathon rest with follow-up four weeks after the race.