Medial Approach to Hip Joint

Medial Approach to Hip Joint indications:

The medial approach to hip, attributed to Ludloff, was originally designed for surgery on flexed, abducted, and externally rotated hips, the kinds of deformities caused by certain types of congenital dislocation of the hip.

The uses of the medial approach to hip joint include the following:

1. Open reduction of developmental dysplasia of the hip.
2. Psoas tendon release (approach gives excellent exposure to psoas tendon).
3. Biopsy and treatment of tumors of the inferior portion of the femoral neck and medial aspect of proximal femoral shaft
4. Obturator neurectomy.
5. The upper part of the approach can be used for an obturator neurectomy.

Position of the Patient

• Place the patient supine on the operating table with the affected hip flexed, abducted, and externally rotated.
• The sole of the foot on the affected side should lie along the medial side of the contralateral knee.

Landmarks and Incision

• Landmarks:
  1. Adductor longus muscle.
  2. pubic tubercle.
• Incision:
  • Make a longitudinal incision on the medial side of the thigh, starting at a point 3 cm below the pubic tubercle.
  • The incision runs down over the adductor longus. Its length is determined by the amount of femur that must be exposed.

Internervous plane

Superficial:

• There is No superficial internervous plane for medial approach to hip, as both the adductor longus and gracilis muscles are innervated by the anterior division of the obturator nerve.

Deep:

The Deep Internervous plane for Medial Approach to Hip Joint lies between adductor brevis and adductor magnus muslces:

1. Adductor brevis supplied by the anterior division of the obturator nerve.
2. Adductor magnus has dual innervation:
   • Adductor portion is supplied by the posterior division of the obturator nerve.
   • Ischial portion by the tibial portion of the sciatic nerve.

Superficial dissection

• Develop a plane between gracilis and adductor longus muscles.

Deep dissection

• Develop plane between adductor brevis and adductor magnus until you feel lesser trochanter on the floor of the wound.
• Try to protect the posterior division of the obturator nerve, the innervation to the muscle’s adductor portion, to preserve the hip extensor function of the adductor magnus.
• Place a narrow retractor (such as a bone spike) above and below the lesser trochanter to isolate the psoas tendon.

Approach Extension

• The medial approach to hip joint can’t be extended.

Dangers

The structures at risk during medial approach to hip joint  include:

1. Medial femoral circumflex artery:
   • Medial femoral circumflex artery passes around medial side of the distal part of the psoas tendon.
   • It’s at risk in children when releasing psoas tendon, psoas tendon must be isolated and cut under direct vision.
2. Anterior division of obturator nerve:
   • It supplies adductor longus, adductor brevis and gracilis muscles in the thigh.
3. Posterior division of obturator nerve:
   • It lies within substance of obturator externus muscle.
   • It supplies adductor portion of adductor magnus.
4. Deep external pudendal artery:
   • It’s at risk proximally.
   • It lies anterior to pectineus near the origin of the adductor longus muscle.

Related Anatomy

The adductor compartment of the thigh consists of three layers of muscles, with the two divisions of the obturator nerve running between each pair of layers.

1. The superficial layer consists of the adductor longus and the gracilis.
2. The middle layer consists of the adductor brevis.
3. The deep layer consists of the adductor magnus.

The adductor longus is the only muscle of the adductor group that is easily palpable at its tendinous origin. Its structure is considered in detail in the superficial surgical dissection.

• The gracilis is extremely long and thin, with long parallel-running fibers. Its aponeurotic origin, a thin sheet of tendinous fibers arising from the pubis, lies in an anteroposterior plane.
• The adductor longus arises by a strong tendon, which accounts for its involvement in the relatively high incidence of avulsion fractures.
• The obturator nerve is derived from anterior divisions of the L2-L4 nerve roots. The nerve divides in the obturator notch into anterior and posterior divisions. The anterior division passes over the upper border of the obturator externus and descends on the medial side of the thigh behind the adductor longus, on the anterior surface of the adductor brevis. It supplies sensory fibers to the hip joint.

References

• Surgical Exposures in Orthopaedics book – 4th Edition
• Campbel’s Operative Orthopaedics book 12th