Research

Muscle Actions on the Spine and Innominates

MuscleLumbo-sacralIliumOriginInsertion
Quadratus Lumborum CNCN Rib 12 & TP L1-4 Iliac crest
Iliacus-CN Iliac fossa Lesser trochanter
Psoas MinorCN- Bodies& discs T12-L1 Fascia of Psoas Major & Iliacus
Psoas MajorCN- TP & discs T12-L5 Lesser trochanter
PiriformisCN- S2-4 Greater trochanter
Obturator Externus-CN Obturator  Greater trochanter
Longissimus T. pars L.CNCN TP L1-4 Iliac crest
Iliocostalis L. pars L.CNCN TP/AP L1-L5 Iliac crest
Longissimus T. pars T.NN TP/Ribs T1-12 SP L3-sacrum & iliac crest
Iliocostalis L. pars T.-N Ribs 7-12 Iliac crest
Spinalis thoracisN- SP T1-10 SP T11-12
Lumbosacral multifidusNN Lumbar SP  Lumbar LP, sacrum, Iliac crest
Gluteus medius – anterior fibers-CN Outer ilium Greater trochanter
Gluteus minimus –anterior fibers-CNOuter ilium Greater trochanter
Rectus femoris-CNAnterior  ilium Patella & tibia
Sartorius-CN Anterior  ilium Tibia
Tensor fascia lata - anterior fibers-CN Anterior  ilium Iliotibial band
Pectineus-CN Pubic ramus Femur
Adductor Brevis-CN Pubic ramus Femur
Gracilis-CN Pubis Tibia
Adductor Magnus – anterior head-CN Ischial ramusFemur
Internal & External Oblique Muscle Slings CN on side of IO,
N on side of EO
CN on side of IO,
N on side of EO
 See individual muscles below See individual muscles below
Internal oblique -CN Iliac crest, inguinal ligament, & TL fascia Linea alba, costal cartilage & ribs 8-12
External oblique-N Outer iliac crest Linea alba, contralateral rectus sheath, & ribs 5-12
Transversus abdominisNN Ribs 6-12, diaphragm, TL fascia, iliac crest, inguinal ligament Pubic crest, internal oblique aponeurosis
Gluteus maximus
(iliac part)
N- Outer ilium Iliotibial band, gluteal tuberosity
Gluteus maximus
(sacral part)
CN- Sacrum Iliotibial band, gluteal tuberosity
Latissimus dorsiCNN SP T6-L3, Iliac crest  Humerus & contralateral GM
GM – Contralateral LD
Muscle Sling
 N on GM side
CN on LD side
N on GM side,
CN on LD side
 See individual muscles above See individual muscles below
Rectus abdominis-N Xiphoid process Pubis
Semitendinosus-N Ischium Tibia
Semimembranosus-N Ischium Tibia
Biceps femoris (long head)CNN Ischial tuberosity & sacrotuberous ligament Fibula
Adductor magnus – posterior head-N Ischial tuberosity Femur
Pelvic FloorCNCN Innominate & various muscles  & fascia Sacrum & various muscles & fascia

 

The table provides the specified muscle or group, action on lumbosacral region and innominate, and origin & insertion.
N=nutation, CN=counternutation, GM = gluteus maximus, LD = latissimus dorsi, IO = internal oblique,
EO = external oblique, T = thoracic/thoracis, L = lumbar/lumborum, TL = thoracolumbar, SP = spinous process,
TP = transverse process, AP = accessory process.