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The Role of Botulinum Toxin Type A in the Clinical Management of Refractory Anterior Knee Pain.

Singer BJ, Silbert BI, Silbert PL, Singer KP - Toxins (Basel) (2015)

Bottom Line: Symptoms can recur in more than two thirds of cases, often resulting in activity limitation and reduced participation in employment and recreational pursuits.Evidence for long term benefit of most conservative treatments or surgical approaches is currently lacking.Initial data suggest that, compared with other interventions for anterior knee pain, Botulinum toxin type A injection, in combination with an active exercise programme, can lead to sustained relief of symptoms, reduced health care utilisation and increased activity participation.

View Article: PubMed Central - PubMed

Affiliation: Centre for Musculoskeletal Studies, School of Surgery M424, the University of Western, 35 Stirling Highway, Nedlands, WA 6009, Australia. barbara.singer@uwa.edu.au.

ABSTRACT
Anterior knee pain is a highly prevalent condition affecting largely young to middle aged adults. Symptoms can recur in more than two thirds of cases, often resulting in activity limitation and reduced participation in employment and recreational pursuits. Persistent anterior knee pain is difficult to treat and many individuals eventually consider a surgical intervention. Evidence for long term benefit of most conservative treatments or surgical approaches is currently lacking. Injection of Botulinum toxin type A to the distal region of vastus lateralis muscle causes a short term functional "denervation" which moderates the influence of vastus lateralis muscle on the knee extensor mechanism and increases the relative contribution of the vastus medialis muscle. Initial data suggest that, compared with other interventions for anterior knee pain, Botulinum toxin type A injection, in combination with an active exercise programme, can lead to sustained relief of symptoms, reduced health care utilisation and increased activity participation. The procedure is less invasive than surgical intervention, relatively easy to perform, and is time- and cost-effective. Further studies, including larger randomized placebo-controlled trials, are required to confirm the effectiveness of Botulinum toxin type A injection for anterior knee pain and to elaborate the possible mechanisms underpinning pain and symptom relief.

No MeSH data available.


Related in: MedlinePlus

Motor points (arrow) of the distal branch of the femoral nerve (adapted from Botter et al. [49]) (A). Dissection showing the distal branch of the femoral nerve to Vastus Lateralis (small arrows), with the Iliotibial band (ITB) reflected posteriorly (B). As illustrated in (C), multiple injection sites, using EMG guidance, were employed to ensure spread of injectate within the distal VL muscle. VLA p = vastus lateralis aponeurosis of the knee joint capsule; RF = rectus femoris muscle; VM = vastus medialis; p = patella. Reprinted with permission from [45]. Copyright 2011 BMJ Publishing Group Ltd.
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toxins-07-03388-f001: Motor points (arrow) of the distal branch of the femoral nerve (adapted from Botter et al. [49]) (A). Dissection showing the distal branch of the femoral nerve to Vastus Lateralis (small arrows), with the Iliotibial band (ITB) reflected posteriorly (B). As illustrated in (C), multiple injection sites, using EMG guidance, were employed to ensure spread of injectate within the distal VL muscle. VLA p = vastus lateralis aponeurosis of the knee joint capsule; RF = rectus femoris muscle; VM = vastus medialis; p = patella. Reprinted with permission from [45]. Copyright 2011 BMJ Publishing Group Ltd.

Mentions: In an initial open label pilot study [43] eight female subjects with chronic AKP (mean symptom duration 5 years, range 1–19 years), who had failed conservative management, were injected with BoNT-A (500 U Dysport®; Ipsen, Paris, France) to VL muscle and underwent a twelve week individualized home exercise program. As illustrated in Figure 1 and Figure 2, motor points for the distal region of VL muscle are clustered immediately above the tendinous aponeurosis. Needle EMG guidance was used to ensure an intramuscular placement of the BoNT-A injectate. Special care was taken in a few cases with excessive subcutaneous fat to ensure the injectate was placed in the VL muscle. During the angled needle insertion, a second resistance from the overlying fascia of the iliotibial band (ITB) may be perceived (Figure 2). The cohort were relatively young (average age 29 years, range 16–40 years) and had been previously physically active, but were now markedly limited by their AKP. Prior to enrollment in this study, a careful clinical examination of potential subjects was undertaken to exclude those with excessive patellofemoral joint laxity or previous patellar dislocation, BMI > 30, or any contra-indications to BoNT-A injection. CT imaging was used to exclude those with marked joint degeneration. At 12 weeks post injection all subjects demonstrated improvements in extensor isometric force production at 30° flexion (p < 0.02) and on a timed stair climbing task (p < 0.002). There was also an improvement in knee pain and related symptoms, however the tool utilized (Knee Injury and Osteoarthritis Outcome scale—KOOS) was found to be relatively insensitive to change in this cohort, who subjectively reported improvements in activity limitation and sporting participation that were not captured by the KOOS. Most importantly, few adverse events were reported and these were minor (e.g., soreness around the injection site) which resolved within a few days [43].


The Role of Botulinum Toxin Type A in the Clinical Management of Refractory Anterior Knee Pain.

Singer BJ, Silbert BI, Silbert PL, Singer KP - Toxins (Basel) (2015)

Motor points (arrow) of the distal branch of the femoral nerve (adapted from Botter et al. [49]) (A). Dissection showing the distal branch of the femoral nerve to Vastus Lateralis (small arrows), with the Iliotibial band (ITB) reflected posteriorly (B). As illustrated in (C), multiple injection sites, using EMG guidance, were employed to ensure spread of injectate within the distal VL muscle. VLA p = vastus lateralis aponeurosis of the knee joint capsule; RF = rectus femoris muscle; VM = vastus medialis; p = patella. Reprinted with permission from [45]. Copyright 2011 BMJ Publishing Group Ltd.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4591644&req=5

toxins-07-03388-f001: Motor points (arrow) of the distal branch of the femoral nerve (adapted from Botter et al. [49]) (A). Dissection showing the distal branch of the femoral nerve to Vastus Lateralis (small arrows), with the Iliotibial band (ITB) reflected posteriorly (B). As illustrated in (C), multiple injection sites, using EMG guidance, were employed to ensure spread of injectate within the distal VL muscle. VLA p = vastus lateralis aponeurosis of the knee joint capsule; RF = rectus femoris muscle; VM = vastus medialis; p = patella. Reprinted with permission from [45]. Copyright 2011 BMJ Publishing Group Ltd.
Mentions: In an initial open label pilot study [43] eight female subjects with chronic AKP (mean symptom duration 5 years, range 1–19 years), who had failed conservative management, were injected with BoNT-A (500 U Dysport®; Ipsen, Paris, France) to VL muscle and underwent a twelve week individualized home exercise program. As illustrated in Figure 1 and Figure 2, motor points for the distal region of VL muscle are clustered immediately above the tendinous aponeurosis. Needle EMG guidance was used to ensure an intramuscular placement of the BoNT-A injectate. Special care was taken in a few cases with excessive subcutaneous fat to ensure the injectate was placed in the VL muscle. During the angled needle insertion, a second resistance from the overlying fascia of the iliotibial band (ITB) may be perceived (Figure 2). The cohort were relatively young (average age 29 years, range 16–40 years) and had been previously physically active, but were now markedly limited by their AKP. Prior to enrollment in this study, a careful clinical examination of potential subjects was undertaken to exclude those with excessive patellofemoral joint laxity or previous patellar dislocation, BMI > 30, or any contra-indications to BoNT-A injection. CT imaging was used to exclude those with marked joint degeneration. At 12 weeks post injection all subjects demonstrated improvements in extensor isometric force production at 30° flexion (p < 0.02) and on a timed stair climbing task (p < 0.002). There was also an improvement in knee pain and related symptoms, however the tool utilized (Knee Injury and Osteoarthritis Outcome scale—KOOS) was found to be relatively insensitive to change in this cohort, who subjectively reported improvements in activity limitation and sporting participation that were not captured by the KOOS. Most importantly, few adverse events were reported and these were minor (e.g., soreness around the injection site) which resolved within a few days [43].

Bottom Line: Symptoms can recur in more than two thirds of cases, often resulting in activity limitation and reduced participation in employment and recreational pursuits.Evidence for long term benefit of most conservative treatments or surgical approaches is currently lacking.Initial data suggest that, compared with other interventions for anterior knee pain, Botulinum toxin type A injection, in combination with an active exercise programme, can lead to sustained relief of symptoms, reduced health care utilisation and increased activity participation.

View Article: PubMed Central - PubMed

Affiliation: Centre for Musculoskeletal Studies, School of Surgery M424, the University of Western, 35 Stirling Highway, Nedlands, WA 6009, Australia. barbara.singer@uwa.edu.au.

ABSTRACT
Anterior knee pain is a highly prevalent condition affecting largely young to middle aged adults. Symptoms can recur in more than two thirds of cases, often resulting in activity limitation and reduced participation in employment and recreational pursuits. Persistent anterior knee pain is difficult to treat and many individuals eventually consider a surgical intervention. Evidence for long term benefit of most conservative treatments or surgical approaches is currently lacking. Injection of Botulinum toxin type A to the distal region of vastus lateralis muscle causes a short term functional "denervation" which moderates the influence of vastus lateralis muscle on the knee extensor mechanism and increases the relative contribution of the vastus medialis muscle. Initial data suggest that, compared with other interventions for anterior knee pain, Botulinum toxin type A injection, in combination with an active exercise programme, can lead to sustained relief of symptoms, reduced health care utilisation and increased activity participation. The procedure is less invasive than surgical intervention, relatively easy to perform, and is time- and cost-effective. Further studies, including larger randomized placebo-controlled trials, are required to confirm the effectiveness of Botulinum toxin type A injection for anterior knee pain and to elaborate the possible mechanisms underpinning pain and symptom relief.

No MeSH data available.


Related in: MedlinePlus