Abductor Hallucis is situated in a unique position to influence deeper structures of the medial aspect of the rearfoot. Hypertrophy of Abductor Hallucis has been reported in the literature to be associated with entrapment of the medial plantar nerve.
A recent review of a 14 year old girl was reported symptomatic relief with 2 injections of Lidocaine.
Hypertrophy of the abductor hallucis muscle: A case report and review of the literature
Lets talk Abductor Hallucis, where is it ? what does it do ? & how can it be involved with heel pain?
Could Dry Needling play a role in management in tibial nerve entrapment involving hypertrophy of abductor hallucis ?
Anatomy – Abductor Hallucis attaches proximally to the medial tuberosity of the calcaneus ,the flexor retinaculum of the ankle and the plantar aponeurosis and intermuscular septum with FDB.
Distally the tendon of abductor Hallucis joins with the medial head of FHB to attatch distally to the medial/ plantar aspect of the base of the proximal phalanx of the hallux.
Innervated by the medial plantar nerve with fibres from L5 7
The tibial nerve branches of Medial plantar nerve, lateral plantar nerve and medical calcaneal nerve lie within close proximity of abductor Hallucis. Shortness, tightness or hypertrophy of Abductor Hallucis could be an irritant to these neural structures resulting in neuritis. If Trigger points are present within the muscle they could be contributing to the symptoms present.
Abductor Hallucis Trigger points can be palpated in the muscle belly , hypertrophy may be evident visually, inhibition or muscle weakness can be tested .
Trigger points can be treated with ischaemic pressure, stretch and spray and dry needling.Trigger points are associated with inhibition of muscle function & shortening of the muscle . Treating a trigger point gives a novel stimulation to the CNS, reeducation , lengthening of the muscle and restoration of painfree ROM is the goal of treatment
In the context of providing a unique and novel input to create a changed neural response in my experience dry needling followed by stretch and spray is an effective tool to address abductor hallucis hypertrophy .
After dry needling the trigger points use of a vapour coolant assists in providing additional input whilst stretching the muscle. Active facilitation of function and home strength exercises should also be incorporated into treatment .
In the referenced article the underlying causes of adbuctor hallucis hypertrophy have not been discussed. Assessing foot performance & addressing underlying foot mechanical deficits would be a method of optimising foot function .The goal of treatment being symptomatic relief, reeducation and prevention of further injury.
How do you manage Abductor Hallucis Hypertrophy and associated tibial nerve entrapment? Have you found manual therapies have given your patient a better a result?
Please leave a comment and let me know.
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Refernce :-Hypertrophy of the abductor hallucis muscle: A case report and review of the literature –Toshinori Kurashi SAGE Open Med Case Rep. 2017 Aug 25;5:2050313X17727638. doi: 10.1177/2050313X17727638. eCollection 2017.