#adductor

Earlier I brought my dresser drawers down to the garage to have dad help me with new holes for the new drawer pulls (that came with too short screws and I could've sworn the seller sent me new ones but I have no fucking clue where they are). I was breathing real heavy halfway through bringing them back upstairs and when I finished, my heart rate had spiked to 180-something. It only took about 5-10 minutes to get back under 100bpm, but I was dizzy and hot and my face was red. I don't like this. But I don't know where to start at this point.

In addition, my ears are hurting periodically and I just realized it's probably because of tension in my head/neck because there's no other symptoms of infection or anything. And, my adductors are still like steel cables and I still haven't taken the time to figure out how to gently stretch those either. Underwear is uncomfortable some days because of how tight they are...

I really need to figure something out. But I'm still scared of doing much without supervision because of the hypermobility and not really knowing the difference between good,/productive pain and bad/destructive pain. And we're going to be moving in a few months and I'm going to be nearly useless. 😥

Why would you name a muscle after its supposed function when its function is actually something totally different? Probably due to what made sense from how it looked, not by how it acted. Of course, we are talking about the abductor hallucis.

Think about all the anatomy you have learned over the years. Think about all the taxonomy and how it was done: sometimes by thename of the discoverer and more often by its anatomical location. The abductor hallucis seems to be the latter. 

The abductor and adductor hallicus function from approximately midstance to pre swing (1-4) (toe off), applying equal and opposite rotational vectors of force (in an ideal world) of the proximal phalynx of the hallux. This should resolve into a purely compressive force (5). In a closed chain environment, the transverse head of the adductor hallicus should act to prevent “splay” of metatarsals, along with the lumbricals and interossei (6), providing stabilzation of the forefoot (7) and rearfoot (8) during preswing, while the oblique head serves to help maintain the medial longitudinal arch. 

The abductor hallicus is actually a misnomer, as it most cases it is not an abductor but rather a plantar flexor of the 1st ray, particularly the proximal hallux, (assisting the peroneus longus) and supinator about the oblique midtarsal joint axis (5).  In the majority of cases, there doesn’t appear to be a separate, distinct insertion of the adductor hallicus to the base of the proximal phalynx, but rather a conjoint insertion with the lateral head of the flexor hallicus bevis into the lateral sesamoid and base of the proximal phalynx (9-11), emphasizing more of its plantar flexion function and stabilizing actions, rather than abduction. 

In one EMG study of 20 people with valgus (12) they looked at activity of adductor and abductor hallucis, as well as flexor hallucis brevis and extensor hallucis longus. They found that the abductor hallucis had less activity than the adductor. No surprise here; think about reciprocal inhibition and increased activity of the adductor when the 1st ray cannot be anchoroed. They also found EMG amplitude greater in the abductor hallucis by nearly two fold in flexion. 

So, the abductor hallucis seems to be important in abduction but more important in flexion. Either way, it is a stance phase stabilizer that we are beginning to know a lot more about. As for the name? You decide...

Dr Ivo Waerlop, one of The Gait Guys

1. Basmajian JV, Deluca CJ . Muscle Alive. Their Functions Revealed by Electromyography Williams and Wilkins. Baltimore, MD 1985, 377

2. Root MC, Orien WP, Weed JH. Normal and Abnormal Function of the Foot. Clinical Biomechanics, Los Angeles, CA 1977

3. Mann RA. Biomechanics of Running. In Pack RP. d. Symposium on the foot and leg in running sports. Mosby. St Louis, MO 1982:26

4. Lyons K, Perry J, Gronley JK. Timing and relative intensity of the hip extensor and abductor muscle action during level and stair ambulation. Phys Ther 1983: 63: 1597-1605

5. Michaud T. Foot Orthoses and Other Forms of Conservative Foot Care. Newton MA 1993: 50-55

6. Fiolkowski P, Brunt D, Bishop et al. Intrinsic pedal musculature support of the medial longitudinal arch: an electromyography study. J Foot & Ankle Surg 42(6) 327-333, 2003

7. Travell JG, Simons DG. Myofascial Pain and Dysfunction: The Trigger Point Manual. Williams and Wilkins, Baltimore 1992; 529

8. Kalin PJ, Hirsch BE. The origin and function of the interosseous muscles of the foot. J Anat 152, 83-91; 1987

9. Owens S, Thordarson DB. The adductor hallucis revisited. Foot Ankle Int. 2001 Mar;22(3):186-91. Am J Phys Med Rehabil. 2003 May;82(5):345-9.

10. Brenner E.Insertion of the abductor hallucis muscle in feet with and without hallux valgus. Anat Rec. 1999 Mar;254(3):429-34.

11. Appel M, Gradinger R. [Morphology of the adductor hallux muscle and its significance for the surgical treatment of hallux valgus][Article in German] Orthop Ihre Grenzgeb. 1989 May-Jun;127(3):326-30.

12. Arinci I, Geng H, Erdem HR, Yorgancioglu ZR Muscle imbalance in hallux valgus: an electromyographic study. Am J Phys Med Rehabil. 2003 May;82(5):345-9.

 Yet another paper (1) to support the notion that the adductors (particularly the adductor magnus, in this paper), act as external rotators (especially eccentrically), not internal rotators as is commonly purported in many anatomy texts (2) . Remember that the lower extremity is internally rotating (as a whole) from initial contact to midstance and externally rotating from midstance to pre swing. SOMETHING needs to help attenuate some of that internal rotation (and pronation) that occurs during the 1st part of stance phase and assist in external rotation (and supination); now you can add the adductor magnus to the popliteus, deep six external rotators, anterior and posterior compartments of the lower leg to the hamstrings and quads.

"This study suggests that adductor magnus has at least two functionally unique regions. Differences were most evident during rotation. The different direction-specific actions may imply that each segment performs separate roles in hip stability and movement. These findings may have implications on injury prevention and rehabilitation for adductor-related groin injuries, hamstring strain injury and hip pathology."

 1. Benn ML, Pizzari T, Rath L, Tucker K, Semciw AI1 . Adductor magnus: An emg investigation into proximal and distal portions and direction specific action. Clin Anat. 2018 Mar 9. doi: 10.1002/ca.23068. [Epub ahead of print]

New Orleans will never be able to build anything meaningful without a solid foundation it can rely on. Zion Williamson, who has missed more than half of the struggling Pelicans’ games this season, has been diagnosed with a grade 2 right hip adductor strain, the team announced. While the Pelicans would not put an official timeline on his return, he is going to miss “extended time” and will be…