Botulinum toxin type A for nonsurgical lateral release in patellofemoral pain syndrome: a case study.

SETTING Outpatient rehabilitation clinic. PATIENT A 37-year-old physically active male. CASE DESCRIPTION The patient presented with anterior left knee pain, exacerbated when climbing stairs, sitting, and running. Exam showed lateral tracking patellae and palpable crepitus. One hundred fifty units of botulinum toxin A was injected into his left vastus lateralis. He underwent a 12-week home exercise program targeting the vastus medialis (VM). ASSESSMENT/RESULTS: Visual analog scale decreased from 70 to 0 on a 150-mm scale, from initial until 8 weeks postinjection. Functional Index Questionnaire increased from 5 to 16 over the same period. Knee torque and surface electromyography findings showed increased activity of the VM during knee extension. CONCLUSION Botulinum injection into the vastus lateralis in conjunction with VM strengthening may provide more effective treatment of patellofemoral pain syndrome. Further study is needed to explore this novel treatment of patellofemoral pain syndrome.