Lower Extremity Surgical Anatomy
Armstrong Milton B. in Lower extremity Trauma, 2006
The gastrocnemius muscle provides force and propulsion in running, jumping, and walking. Along with the soleus it is the chief plantar flexor of the foot. The gastrocnemius is also a knee flexor. It is a 20 × 8 cm2 muscle that is type I. It originates on the medial condyle of the femur and the lateral head of the femoral condyle (which often contains a sesamoid bone in the tendinous origin of the head) where it forms the inferior medial and lateral border of the popliteal fossa. The medial head is larger and descends more distally than the lateral head. The fleshy muscle descends until midcalf where it inserts into a broad aponeurosis and inserts into the calcaneous via the tendon calcaneous. The plantaris muscle can be identified in most individuals separating the gastrocnemius and soleus muscles. It is innervated by the tibial nerve and is vascularized by the sural arteries. The skin over the medial gastrocnemius receives sensory innervations from the saphenous nerve, and laterally the sural nerve innervates the skin over the lateral gastrocnemius. Either or both heads of the gastrocnemius are expendable if the soleus is intact. The gastrocnemius based superiorly is used to cover the knee and upper third tibia defects. Distally based flap can be used to cover middle third leg defects.
Lower Limb Muscles
Eve K. Boyle, Vondel S. E. Mahon, Rui Diogo in Handbook of Muscle Variations and Anomalies in Humans, 2022
Using MRI, Herzog (2011) found accessory plantaris muscles in 63 of 1,000 (6.3%) symptomatic patients. In 62 cases, the normal plantaris and accessory plantaris had merged origins. One accessory plantaris muscle originated with the lateral head of the gastrocnemius muscle. The accessory plantaris muscles had insertions into the iliotibial tract in 5 out of the 63 cases (7.9%), the lateral patellar retinaculum in 15 cases (23.8%), and the iliotibial band in 43 cases (68.3%) (Herzog 2011). Ashaolu et al. (2014) studied gastrocnemius and plantaris in 60 legs from 30 Nigerian cadavers. In the legs with a two-headed gastrocnemius (21 legs), there was 100% simultaneous occurrence of plantaris. In the legs with multi-headed gastrocnemius (39 legs), there was 90% simultaneous occurrence of plantaris. Plantaris was thus present in 56 out of 60 legs (93.3%).
A to Z Entries
Clare E. Milner in Functional Anatomy for Sport and Exercise, 2019
The posterior muscles of the ankle and foot are gastrocnemius, soleus, plantaris, flexor digitorum longus, flexor hallucis longus, and tibialis posterior. As a group, these muscles cross the back of the ankle and plantarflex the ankle. Gastrocnemius is the large two-headed muscle that forms the bulk of the calf and also flexes the knee (see knee – muscles) and supinates the foot. The next largest muscle of the calf is soleus, which lies deep to the gastrocnemius; its action is purely plantarflexing the ankle. Between these two muscles lies the small plantaris muscle, which makes a minor contribution to flexing the knee and plantarflexing the ankle. Deep to these muscles lies popliteus; this muscle contributes to flexing the knee and internally rotating the tibia. Flexors digitorum and hallucis longus flex the four lesser toes and great toe respectively. Tibialis posterior supinates the foot in addition to plantarflexing the ankle. Two muscles are situated laterally on the leg, peroneus longus and peroneus brevis. Their role is pronating the foot and plantarflexing the ankle. The intrinsic muscles of the foot contribute to movement of the toes. There are many muscles within the foot, with the muscles of the dorsum of the foot being four layers deep.
Differential effects of heat stress on fibre capillarisation in tenotomised soleus and plantaris muscles
Published in International Journal of Hyperthermia, 2018
Muthita Hirunsai, Ratchakrit Srikuea
Taken together, the aims of this study were to evaluate the effects of heat stress on the adaptation of capillary content, angiogenic regulators and fibre-type composition after Achilles tendon transection in rat soleus (tenotomised soleus) and plantaris (tenotomised plantaris) muscles. Both muscle types were chosen in this study because soleus represents the predominantly slow-twitch and oxidative postural muscles, whereas plantaris muscle represents predominantly fast-twitch and glycolytic muscles [22]. Since tendon rupture is commonly encountered following trauma or degenerative musculoskeletal diseases [23], we chose this animal model in the present study. Here, we hypothesised that heat stress could alleviate capillary regression of tenotomised muscle in different angiogenic responses between soleus and plantaris muscles. In addition, heat stress-induced capillarisation could be associated with the promotion of slow-oxidative fibre in disuse muscle atrophy.
Developmental mechanisms of CPSP: Clinical observations and translational laboratory evaluations
Published in Canadian Journal of Pain, 2022
Suellen M. Walker
Plantar hind paw incision incorporates incision of the skin and underlying plantaris muscle and produces cellular and molecular alterations specific to this type of injury.6,12,13 Acute behavioral hyperalgesia (reduced hindlimb reflex thresholds) is evoked, with the degree and duration of sensitivity influenced by postnatal age14,15 but not sex.16 In younger animals, incision-induced electrophysiological changes in large dorsal root ganglion neurons persist beyond the period of behavioral hyperalgesia, afferent-evoked activity in second-order dorsal horn neurons is more marked and rapid,17,18 and noxious-evoked potentials in the somatosensory cortex are enhanced and more resistant to increasing isoflurane anesthesia.19 In addition, incision produces developmentally regulated long-term changes in nociceptive processing and response to re-incision20,21 that differ from other injury models (see reviews for inflammatory, nerve injury, arthritis, stress, and immune challenge models7,11,22–28).
Impact of methionine restriction on muscle aerobic metabolism and hypertrophy in young and old mice on an obesogenic diet
Published in Growth Factors, 2022
Anandini Swaminathan, Leonardo Cesanelli, Tomas Venckunas, Hans Degens
During the twelfth week of the dietary intervention, compensatory hypertrophy of the right plantaris muscles was induced in all mice by cutting the branches of the n. Ischiadicus supplying the m. gastrocnemius and m. soleus as close to their point of entry to the belly of the muscle as possible. A segment of each branch was removed to prevent reinnervation. The left plantaris muscle served as the internal control. The surgery was performed under anaesthesia (isoflurane—4% and O2 at 2 L·min−1 until the animal did not respond to foot-pad-pinch, and then maintained with 1.5% isoflurane and 1 L·min−1 O2).
Related Knowledge Centers
- Achilles Tendon
- Femur
- Gastrocnemius Muscle
- Muscle
- Soleus Muscle
- Tendon
- Posterior Compartment of Leg
- Fascial Compartments of Leg
- Body
- Knee