Cerebral Palsy — Adductor Release for Hip Subluxation

PaediatricsAdvancedCore Procedure

Cerebral Palsy — Adductor Release for Hip Subluxation

Operative technique guide for open adductor longus, gracilis and selective brevis tenotomy with iliopsoas lengthening via medial groin approach for spastic hip displacement in cerebral palsy — indications, hip surveillance thresholds, nerve protection and combined bony reconstruction

High-yield overview

Open adductor longus, gracilis and selective brevis tenotomy with iliopsoas lengthening via medial groin approach | advanced

Surgical Imaging

Critical Danger Structures and Exam Traps
Anterior Obturator Nerve — Protection Mandatory

Location: The anterior branch of the obturator nerve lies on the surface of adductor brevis, medial to the adductor longus insertion and courses distally in the interval between adductor longus and brevis.

Risk: Transection produces loss of adductor function and, if combined with posterior branch injury, complete adductor paralysis. Deliberate neurectomy is contraindicated because it leads to abduction contracture, poor sitting balance and perineal hygiene difficulties.

Protection: Identify the nerve under direct vision, gently retract it medially with a vessel loop, and preserve it throughout the release. Selective partial neurectomy is occasionally considered only in non-ambulatory patients with severe adductor spasticity after careful discussion of abduction contracture risk.

Medial Femoral Circumflex Artery — Vascular Landmark

Location: The medial femoral circumflex artery runs along the inferior border of the adductor longus insertion and enters the thigh between adductor longus and magnus before ascending posteriorly to supply the femoral head via the retinacular vessels.

Risk: Laceration causes brisk bleeding and potential compromise of femoral head vascularity if the ascending branch is injured. The vessel is at greatest risk during distal extension of the adductor longus tenotomy.

Protection: Identify the artery at the distal edge of the adductor longus tendon before completing the tenotomy; ligate or cauterise small branches only after clear visualisation. Maintain a plane superficial to the vessel during gracilis release.

Hip Joint Capsule — Avoid Violation

Location: The capsule lies deep to the adductor brevis and iliopsoas tendon at the level of the lesser trochanter. Excessive medial retraction or deep dissection can enter the joint.

Risk: Capsular violation leads to instability, heterotopic ossification, and potential septic arthritis if infection occurs. In spastic hips the capsule is often thickened and adherent to the spastic tendons.

Protection: Stay extra-capsular at all times. Use blunt dissection and direct visualisation when releasing fibres of adductor brevis near the joint. If the capsule is inadvertently entered, repair with absorbable suture and consider post-operative antibiotics.

Over-Release and Abduction Contracture

Location: Excessive release of adductor brevis or combined anterior obturator neurectomy removes the last remaining adductor power.

Risk: Abduction contracture greater than 30-40 degrees prevents comfortable seating, perineal care and transfers. It is functionally worse than the original adduction contracture in non-ambulatory patients.

Prevention: Release only adductor longus, gracilis and the anterior 50-70 percent of adductor brevis fibres. Leave the posterior third of brevis and the full adductor magnus intact. Never perform complete anterior obturator neurectomy.

Iliopsoas Tendon Identification

Location: The iliopsoas tendon inserts on the lesser trochanter; the tendon is palpated medial to the pectineus and deep to the adductor brevis interval.

Risk: Missing the tendon leads to persistent hip flexion contracture. Mistaking the rectus femoris tendon for iliopsoas produces incorrect lengthening and residual flexion deformity.

Identification: With the hip flexed and externally rotated, the iliopsoas tendon is the taut cord running from the pelvic brim to the lesser trochanter. Confirm by palpation of the lesser trochanter and by observing tension with hip flexion against resistance.

Wound Healing in Spastic Patients

Location: The medial groin incision lies in a skin crease with high bacterial load and is subject to shear forces from spastic adductor tone and positioning devices.

Risk: Wound dehiscence, deep infection and heterotopic ossification are more common than in non-spastic patients. Malnutrition, gastrostomy dependence and poor skin quality compound the risk.

Prevention: Use meticulous layered closure, consider prophylactic antibiotics for 24 hours, delay aggressive abduction bracing for 10-14 days, and optimise nutrition pre-operatively. Monitor for early signs of wound breakdown at 48-72 hours.

Mnemonic

A.D.D.U.C.T.O.RADDUCTOR — Surgical Goals and Limits

Mnemonic

S.P.A.S.T.I.CSURVEILLANCE — Hip Displacement Monitoring in CP

Surgical Indications

Absolute Indications

  • Progressive hip subluxation with migration percentage greater than 30-40 percent on serial surveillance radiographs despite optimised tone management
  • Abduction less than 20-30 degrees with the hip extended, producing inability to maintain seating or perform perineal hygiene
  • Painful spastic hip with radiographic displacement that limits quality of life or nursing care
  • Established dislocation in a non-ambulatory patient when reduction and containment are still feasible (usually before skeletal maturity)

Relative Indications

  • Borderline migration (25-35 percent) with rapidly increasing tone or loss of abduction on serial examinations
  • Ambulatory patient with deteriorating Trendelenburg gait and abduction contracture less than 20 degrees
  • Pre-operative optimisation before planned femoral or pelvic osteotomy in a child with established displacement
  • Severe adductor spasticity interfering with orthotic wear or therapy participation

Contraindications

Absolute:

  • Fixed abduction contracture greater than 30 degrees (release would worsen function)
  • Active infection or untreated pressure sores in the groin or perineum
  • Non-reducible dislocation with severe acetabular deficiency where containment is no longer possible

Relative:

  • Very young age (less than 3-4 years) unless migration is rapidly progressive — trial of tone management first
  • Severe osteopenia with high fracture risk during positioning
  • Medical comorbidities that preclude safe anaesthesia for the combined procedure

Evidence for Soft-Tissue Release

Hip Surveillance and Timing

  • Early identification of migration percentage greater than 30 percent allows soft-tissue release before irreversible acetabular dysplasia develops
  • Delaying surgery until migration exceeds 50 percent or dislocation occurs significantly reduces the success rate of containment procedures

Adductor Release Outcomes

  • Isolated adductor release reduces migration percentage by 10-20 percent in early subluxation (less than 40 percent) and improves abduction by 15-25 degrees in most series
  • Success is highest when performed before 5-6 years of age and when combined with iliopsoas lengthening and post-operative abduction positioning
  • In established displacement greater than 40 percent, soft-tissue release alone fails to maintain containment in greater than 60 percent of cases at 5 years — bony reconstruction is required

Combined Procedures

  • Adductor release plus iliopsoas lengthening plus femoral varus derotation osteotomy achieves stable containment in 70-85 percent of children with migration 40-60 percent
  • Addition of pelvic osteotomy (Dega, Salter or Pemberton) further improves acetabular coverage and reduces redislocation risk to less than 15 percent at 10 years

Clinical Decision Scenarios

Practise clinical reasoning and management decisions out loud

Viva scenarioAdvanced
Clinical prompt

A 6-year-old non-ambulatory child with spastic quadriplegic cerebral palsy has a migration percentage of 38 percent on the right hip and 25 percent on the left. Abduction is 15 degrees on the right and 35 degrees on the left. The child has increasing difficulty with seating and perineal hygiene. What is your surgical plan?

Practical approach
This child has progressive right hip subluxation with functional abduction loss that meets surgical criteria. I would recommend bilateral adductor release with iliopsoas lengthening via a medial groin approach, combined with right femoral varus derotation osteotomy and pelvic osteotomy because migration exceeds 35-40 percent and bony reconstruction is required for durable containment. **Pre-operative planning**: I would obtain recent AP pelvis radiographs to confirm migration percentage and acetabular indices, assess for scoliosis or pelvic obliquity that may influence containment, and optimise nutrition and tone management (baclofen, botulinum toxin) in the months before surgery. **Surgical sequence**: Bilateral medial groin incisions. Release adductor longus, gracilis and anterior 50-70 percent of adductor brevis on both sides while protecting the anterior obturator nerve. Lengthen iliopsoas over the pelvic brim. On the right side, proceed to femoral varus derotation osteotomy (typically 20-30 degrees varus and 20-30 degrees derotation) with blade-plate or locking-plate fixation, followed by Dega-type pelvic osteotomy to improve acetabular coverage. Close all wounds and apply an abduction brace or spica cast. **Post-operative care**: Abduction positioning for 6-12 weeks, staged weight-bearing as fixation stability allows, and surveillance radiographs at 3, 6 and 12 months to confirm containment. Long-term tone management and therapy input are essential to maintain the correction.
Viva scenarioAdvanced
Clinical prompt

During medial groin adductor release in a 5-year-old child you identify the anterior obturator nerve on the surface of adductor brevis. The assistant asks whether you should perform an anterior obturator neurectomy to improve the abduction gain. How do you respond and what is your rationale?

Practical approach
I would not perform an anterior obturator neurectomy. Deliberate neurectomy produces abduction contracture, impairs sitting balance and perineal hygiene, and removes the last remaining adductor power needed for transfers — the functional result is worse than the original adduction contracture. **Rationale**: The anterior branch supplies adductor longus, brevis and gracilis. Sectioning it removes the very muscles we are releasing and leaves the child with unopposed abductors. In non-ambulatory patients the loss of adductor tone leads to progressive abduction contracture that prevents comfortable seating and makes perineal care impossible. The literature and clinical consensus strongly advise against routine neurectomy. **Alternative strategy**: I achieve adequate abduction by releasing adductor longus, gracilis and the anterior 50-70 percent of adductor brevis fibres while preserving the posterior third of brevis and the full adductor magnus. This provides 30-40 degrees of abduction without creating an abduction contracture. The anterior obturator nerve is identified and protected with a vessel loop throughout the procedure.
Viva scenarioAdvanced
Clinical prompt

A 4-year-old ambulatory child with spastic diplegia has bilateral migration percentages of 32 percent, abduction of 18 degrees, and a 20-degree hip flexion contracture. The family reports deteriorating gait and increasing falls. Outline your surgical plan and the rationale for including or excluding iliopsoas lengthening.

Practical approach
This ambulatory child has bilateral progressive subluxation with functional abduction loss and flexion contracture that together impair gait. I would recommend bilateral adductor release with selective iliopsoas recession (not over-the-brim tenotomy) via the medial approach, performed before skeletal maturity to preserve ambulatory potential. **Rationale for iliopsoas management**: In ambulatory patients, recession at the lesser trochanter insertion is preferred over intra-pelvic tenotomy over the pelvic brim. Recession preserves some hip flexion power needed for standing from sitting and stair climbing, while still correcting the contracture. Over-the-brim tenotomy risks greater loss of flexion power and is reserved for non-ambulatory children with severe flexion deformity. **Surgical details**: Bilateral medial groin incisions. Release adductor longus, gracilis and anterior 50-70 percent of brevis while protecting the anterior obturator nerve. Identify the iliopsoas tendon at the lesser trochanter and perform fractional lengthening or Z-lengthening at the insertion. Verify that hip extension improves to neutral without creating excessive weakness. Close and apply abduction positioning. **Post-operative plan**: Immediate weight-bearing as tolerated, gentle therapy focusing on gait and balance, night-time abduction brace for 6-12 weeks, and surveillance radiographs every 6 months until skeletal maturity. If migration progresses despite soft-tissue release, plan femoral varus derotation osteotomy before age 6-7 years.
Exam day cheat sheet
Cerebral Palsy — Adductor Release for Hip Subluxation — Exam Day Summary

References

Evidence

Soft-tissue release for spastic hip subluxation in cerebral palsy

Level III
Miller F, Cardoso Dias R, Dabney KW, et al.J Pediatr Orthop
Clinical implication: Selective release without neurectomy is effective for early displacement while preserving adductor function.
Source: J Pediatr Orthop 1997;17(5):571-84
Evidence

Soft-tissue releases to treat spastic hip subluxation in children with cerebral palsy

Level III
Presedo A, Oh CW, Dabney KW, Miller FJ Bone Joint Surg Am
Clinical implication: Confirms selective adductor release efficacy when performed before severe displacement.
Source: J Bone Joint Surg Am 2005;87(4):832-41
Evidence

Prevention of spastic paralytic dislocation of the hip

Level III
Kalen V, Bleck EEDev Med Child Neurol
Clinical implication: Reinforces nerve-sparing selective release and pre-operative nutrition optimisation.
Source: Dev Med Child Neurol 1985;27(1):17-24
Evidence

Management of hip disorders in patients with cerebral palsy

Level IV
Flynn JM, Miller FJ Am Acad Orthop Surg
Clinical implication: Provides practical decision thresholds for timing adductor release within hip surveillance programmes.
Source: J Am Acad Orthop Surg 2002;10(3):198-209
Editorially reviewed — transparent references and correction processPublished by OrthoVellum Medical Education TeamEditorial boardMethodologyReview policy
Educational disclosure

Educational content is reviewed for source visibility, editorial coherence, and correction readiness.

No individual clinician credential is claimed unless a named person is shown.

Verify before clinical use; this is not medical advice or a substitute for local guidance.