Tables 10-13 provide details of the muscles of the thigh and buttock, and figure 79a–d shows the bones and muscles of the region. Hip joint abnormalities can have marked effect on gait. This can also be produced by musculoskeletal abnormalities elsewhere in the spine, pelvis and lower limbs, and painful soft tissue conditions. Interpretation is therefore dependent on a detailed general examination, directed by the patient’s history.

Table 10 Muscles of the buttock region ( Buttock)

Table 11 Muscles of the posterior (flexor) compartment of the thigh

Table 12 Muscles of the medial (adductor) compartment of the thigh

Table 13 Muscles of the anterior (extensor) compartment of the thigh

Note during your initial acquaintance with the patient the rhythm and timing of each step, and the pressure applied on each foot. Inadequate gluteal muscles and congenital dislocation of the hip joint produce waddling gaits. Other common neurological abnormalities are the shuffling gait of Parkinson’s, spastic hemiplegic, the paralysis of lower motor neurone lesions and the incoordination of cerebellar disease.

Compensatory movement of the pelvis can mask abnormalities of hip movement; various manoeuvres are thus required to distinguish between the two components. Active and passive movements in each direction are examined concurrently to avoid frequent repositioning the patient. The ipsilateral hand is used to hold the leg during passive movement while the other is used to feel for pelvic movement.

 

Hip flexion is limited by thigh contact with the trunk and is normally 90-100 degrees (figure 80a–d); it is increased when combined with knee flexion, due to relaxation of the hamstring muscles. Passive flexion also increases the range.

Some apparent hip flexion is due to flexion of the lumbar spine and pelvic tilting. This can be confirmed by placing your hand, palm downward, behind the lumbar curve during active and passive hip flexion

Fixed flexion of the hip joint may limit flexion. The amount of this fixed flexion can be assessed by Thomas’ test (figure 81). In this the normal hip is flexed until the lumbar curve is just flattened. This is determined by your left hand placed behind the lumbar spine. At this point, the number of degrees of elevation of the contralateral hip from the horizontal denotes the degree of fixed flexion.

Abduction and adduction (figure 82a–d) are tested after raising the heel clear of the contralateral leg. Monitor pelvic movement by placing your left hand on one, or across both, anterior superior iliac spines. The movements are 45 degrees abduction and 30 degrees adduction, from a plane at right angles to a line through the two anterior superior iliac spines.

Rotation can be assessed in both flexion and extension. In the former, the hip and knee are both flexed to 90 degrees and the foot moved medially (externally rotation – figure 83a,b) and laterally (internal rotation – figure 83c–d), they are respectively 45 and 20 degrees. In extension, the subject lies prone and rotation is assessed with the knee flexed to 90 degrees.

Extension of the hip joint is 10–20 degrees and can be tested with the patient lying on the contralateral side, or lying prone and lifting the leg off the couch (figure 84a–d).

Examination of the hip is completed by observing the patient standing, walking and running (figure 85a–c). The act of standing and the stance, should be observed for discomfort and disability.

Figure 79 Lower limb anatomy:

a. Anterior

1. Iliacus
2. Lateral part (ala) of sacrum
3. Anterior superior iliac spine
4. Sartorius
5. Femoral nerve
6. Iliopsoas
7. Straight head of rectus femoris
8. Femoral artery
9. Inguinal ligament
10. Tensor fasciae latae
11. Femoral vein
12. Pectineus
13. Piriformis
14. Pubic tubercle
15. Gluteus minimus
16. Adductor longus
17. Obturator externus
18. Adductor brevis
19. Vastus lateralis
20. Gracilis
21. Quadratus femoris
22. Adductor magnus
24. Vastus intermedius
25. Vastus medialis
26. Quadriceps tendon
27. Patellar tendon

Figure 79 Lower limb anatomy

b. Posterior

1. Iliac crest
2. Gluteus medius
3. Tensor fasciae latae
4. Posterior superior iliac spine
5. Gluteus minimus
6. Gluteus maximus;
sacrum and ilium to gluteal tuberosity on femur
7. Posterior inferior iliac spine
8. Rectus femoris, oblique head
9. Acetabular rim
10. Spine of ischium
11. Body of pubis – posterior aspect
12. Symphysis pubis
13. Obturator externus
14. Obturator foramen
15,16. Hamstrings
17. Vastus lateralis
18. Adductor magnus
19. Ischial tuberosity
20. Iliopsoas
21. Pectineus
22. Gracilis
23. Adductor brevis
24. Adductor longus
25. Semitendinosus
26. Vastus intermedialis
27. Biceps
28. Vastus medialis
29. Short head of biceps
30. Iliotibial tract
31. Gastrocnemius, medial head
32. Gastrocnemius, lateral head
33. Semimembranosus
34. Intercondylar notch

Figure 79 Lower limb anatomy

c. Lateral thigh bones

1. Iliac crest
2. Tubercle – palpable projection: intertubercular line, an abdominal marker
3. Gluteus medius: outer ilium to greater trochanter
4. Tensor fasciae latae
5. Posterior superior iliac spine
6. Gluteus minimus
7. Gluteus maximus: from posterior ilium and sacrum, to tuberosity on femur
8. Anterior superior iliac spine
9. Sartorius
10. Straight and 12. oblique heads of rectus femoris,
11. Posterior inferior iliac spine
13. Head of femur
14. Spine of ischium
15. Symphysis pubis
16. Obturator foramen
17. Hamstring muscles from ischial tuberosity
18. Adductor magnus from ischial tuberosity
19. Vastus lateralis
20. Vastus intermedius
21. Lateral head of gastrocnemius,
22. Popliteus: to lateral aspect lateral femoral condyle
23. Patella
24. Lateral tibial condyle
25. Head of fibula

Figure 79 Lower limb anatomy

d. Lateral thigh muscles

1. Gluteus medius
2. Tensor fasciae latae
3. Sartorius
4. Gluteus maximus
5. Rectus femoris
6. Semitendinosus
7. Biceps femoris
8. Vastus lateralis
9. Iliotibial tract
10. Quadriceps tendon
11. Common peroneal nerve
12. Lateral head of gastrocnemius
13. Patellar tendon

When standing on one leg (figure 86) the opposite side of the pelvis is raised by abduction of the hip joint on the weight bearing leg. This can be confirmed when standing behind the patient, comparing the buttock creases and palpating the two anterior superior iliac spines. In some hip joint abnormalities, abduction is lost and, on standing on one leg, the opposite side of the pelvis drops. This is known as a positive Trendelenburg sign.