Clinical trial NCT00496964: Botox for Non-surgical Lateral Release in Patellofemoral Pain
Official title: Botox for Non-surgical Lateral Release in Patellofemoral Pain
Study type: INTERVENTIONAL
Overall status: TERMINATED
Phase: PHASE3
Conditions: Patellofemoral Pain Syndrome
Keywords: Botulinum toxin type A
Patellofemoral pain syndrome
Knee Injuries
Exercise Therapy
Lead sponsor: Virginia Commonwealth University
Sponsor class: OTHER
Collaborators: name: Allergan
First posted: 2007-07-06
Enrollment: 5
Sex: ALL
Minimum age (years): 18
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to determine whether the use of botulinum toxin A injected into the lateral thigh muscle improves knee function and reduces knee pain secondary to patellofemoral syndrome. The study hypothesis is that botulinum toxin + specific exercises will be superior to specific exercises alone in improving knee function and reducing knee pain in individuals with patellofemoral syndrome.

Detailed description: Patellofemoral pain syndrome is a leading cause of knee pain in persons under 45 and is particularly common in women. The prevailing theory for the etiology of patellofemoral pain is an imbalance in force or timing of the pull of the knee extensor muscles on the patella resulting in improper tracking of the patella in the femoral grove. Specifically, the vastus medialis is thought to be ineffective in overcoming the lateral pull of the vastus lateralis. When exercises designed to focus on improving strength and timing of activation of the vastus medialis fail, surgical release of part of the attachment of the vastus lateralis to the patella is considered.

Botulinum toxin temporarily blocks acetylcholine release from motor neurons and is used clinically to produce muscle relaxation.

Subjects with patellofemoral syndrome will be recruited into the study. Half of the subjects will be given a placebo injection while the other half will be given an injection of Botox (Botulinum Toxin A, Allergen) into the vastus lateralis muscle. Group assignment will be randomized and a double blind protocol used. Prior to injection, the subject will record their level of knee pain, fill out several knee function questionnaires, and have the strength and endurance of their knee extensor muscles tested. All subjects will be given an exercise program designed to target strengthening of the medial thigh muscles as well as stretching of lateral structures.

At 4, 6 and 12 weeks knee pain and knee function will again be assessed.

Eligibility criteria: Inclusion Criteria:

* retropatellar knee pain
* pain with two of: prolonged sitting, climbing stairs, squatting, running, kneeling, hopping, jumping
* pain with patellar palpation
* symptoms minimum 1 month
* Visual Analog Scale for pain (VAS) usual pain 4 of 10 on VAS \[0-10 scale, anchors 0 = no pain, 10 = worst pain imaginable\]

Exclusion Criteria:

* history knee surgery
* history patellar dislocation
* clinical evidence of meniscal lesion, ligamentous instability, traction apophysitis around the patellofemoral complex, patellar tendon pathology, chondral damage, osteoarthrosis, spinal referred pain

Primary outcomes:
measure: Visual Analog Scale Pain Ratings (VAS)
timeFrame: 4, 6, 12 weeks
measure: Change in Anterior Knee Pain Scale.
timeFrame: 4, 6, 12 weeks
measure: Functional Index Questionnaire
timeFrame: 4, 6, 12 weeks
measure: Lower Extremity Functional Scale
timeFrame: 4, 6, 12 weeks
Secondary outcomes:
measure: Maximal Knee Extensor Force During Concentric and Isometric Contractions
timeFrame: 4, 6, 12 weeks
measure: Knee Extensor Fatigue
timeFrame: 4, 6, 12 weeks
measure: Muscle Activation During Maximal Contractions and Fatigue Contractions
timeFrame: 4, 6, 12 weeks
Other outcomes:
Locations:
city: Richmond
country: United States
facility: Virginia Commonwealth University
state: Virginia
Study officials:
affiliation: Department of Physical Therapy, Virginia Commonwealth University
name: Sheryl D Finucane, PhD, PT
role: PRINCIPAL_INVESTIGATOR
References:
citation: Singer BJ, Silbert PL, Dunne JW, Song S, Singer KP. An open label pilot investigation of the efficacy of Botulinum toxin type A [Dysport] injection in the rehabilitation of chronic anterior knee pain. Disabil Rehabil. 2006 Jun 15;28(11):707-13. doi: 10.1080/09638280500301477.
citation: Crossley K, Bennell K, Green S, McConnell J. A systematic review of physical interventions for patellofemoral pain syndrome. Clin J Sport Med. 2001 Apr;11(2):103-10. doi: 10.1097/00042752-200104000-00007.
citation: Crossley KM, Bennell KL, Cowan SM, Green S. Analysis of outcome measures for persons with patellofemoral pain: which are reliable and valid? Arch Phys Med Rehabil. 2004 May;85(5):815-22. doi: 10.1016/s0003-9993(03)00613-0.