PELVIC OSTEOTOMYFOR THE TREATMENT OF

THE YOUNG ADULT WITH HIP PAIN

Emmanuel Illical, Adult Reconstruction Fellow

OUTLINE• Pelvic osteotomy introduction• Background: hip dysplasia• Bernese periacetabular osteotomy (PAO)

– Technique & Surgical adjuncts

– Advantages & Complications

– Clinical Results

• Background: acetabular retrotorsion• Reverse PAO

– Principles

– Clinical Results

• Other osteotomies• Salvage Osteotomies• Summary

• Treatment of choice for acetabular structural disorders for young pts– classical developmental hip dysplasia

– retrotorsional acetabular abnormalities

• Indications– symptomatic patient (pain / progressive limp)

– radiographically negative for advanced OA

– adequate and relatively painless passive ROM

• Rationale– restore normal hip anatomy and biomechanics

• increase joint congruity

• optimize center of rotation

– relieve symptoms

– prevent (possibly delay?) degenerative changes

• Challenges: diagnosis & predictability of outcome

PELVIC OSTEOTOMY: INTRODUCTION

• Acetabular abnormalities– shallow

– anteverted (retrortosion in up to 25%)

– lateralized

– femoral head coverage deficient anteriorly, laterally, superiorly

• Femoral abnormalities– proximal migration– femoral head small and deformed– femoral neck short and narrrow w/ varying but but anteversion– valgus neck shaft angle– femoral canal narrow

• Secondary degenerative joint disease over time contact area btwn femoral head and acetabulum

– excessive lateralization of body weight lever arm body weight lever arm

– relatively high forces transmitted through surface area

BACKGROUND: HIP DYSPLASIA

BACKGROUND: HIP DYSPLASIA

BACKGROUND: HIP DYSPLASIA

BERNESE PAO: TECHNIQUE

• Anterior arthrotomy: before or after PAO– labral pathology: debridement / repair

– femoral head neck junction: osteochondroplasty

• Proximal femoral osteotomy– severe coxa valga / vara varus / valgus producing intertrochanteric osteotomy

BERNESE PAO: SURGICAL ADJUNCTS

• Only one incision that spares ABductors• Reproducible extra-articular osteotomies• Allows large corrections in all directions• Posterior column remains intact

– minimal internal fixation required

– early mobilization w/o external immobilization

• Preservation of acetabular fragment vascularity– intra-articular examinzation w/o further risk of devascularization

• True pelvis shape is unchanged– child bearing & vaginal delivery not affected

BERNESE PAO: ADVANTAGES

• Most important factor affecting incidence = surgeon experience

• Most common complication = nerve dysfunction– lateral femoral cutaneous nerve (35%)

– femoral nerve

– sciatic / peroneal nerve

• Vascular – related ilioinguinal approach: femoral / iliac artery thrombosis

• Inadvertent extension of osteotomy to undesirable location– intra-articular extension of infra / supra – acetabular osteotomies

– sciatic notch extension of iliac osteotomies

• Femoroacetabular impingement

• Osteonecrosis of acetabular fragment

• Nonunion

• Other: HO, loss of correction, femoral head subluxation

BERNESE PAO: COMPLICATIONS

BERNESE PAO: CLINICAL RESULTS

BERNESE PAO: CLINICAL RESULTS

• Posteriorly oriented acetabular opening (sagittal plane)• Etiology

– isolated entity

– associated w/ classic hip dysplasia

– injury to tri-radiate cartilage in growing child

– associated with LCP, bladder extrophy, neuromuscular d/o

• Typical presentation is groin pain reproduced with “impingement signs”

• Recurrent impingement has been implicated in development of 2* arthrosis

BACKGROUND: ACETABULAR RETROTORSION

BACKGROUND: ACETABULAR RETROTORSION

• Treatment of choice when acetabular retrotorsion exists– +ve crossover sign AND +ve posterior wall sign (poor posterior coverage)

– addresses lack of posterior wall coverage by increasing anteversion

• Technique– same approach and osteotomies as PAO

– re-orientation achieved by combined flexion + IR of acetabular fragment

– goals: eliminate xray signs+ sufficient impingement free ROM (flexion + IR)

– posterior over-coverage is a concern

– arthrotomy / SHD to address femoral head neck offset & labral pathology

• Contra-indications– excessive posterior wall coverage / AI < 0* impingement

– significant combined CAM / pincer deformity requires surgical hip dislocation

– advanced cartilage degeneration area would end up in weight bearing zone

REVERSE PAO: PRINCIPLES

• Siebenrock et al. JBJS Am 2003. Impingement due to acetabular retroversion. Treatment with PAO.– 29 reverse PAOs to reorient retroverted acetabulum (+ve cross over / pw sign)– concominant femoral head neck osteochondroplasty in 24 hips– avg 30 month f/u– significant increase in flexion / IR / ADduction– significant d’Aubigne hip score improvement: 14.0 16.9– 28 “good / excellent” results– no pt had radiographic signs of OA– 3 revisions

• Buchler et al. JBJS Br 2011. Symptomatic acetabular retroversion: mean 10 year fu after treatment with PAO.– mean f/u 10.6 year – overall d’Aubinge score improved: 14.0 16.3– all patients had symptomatic relief at final f/u– ROM and functional scores improved in all cases– vast majority of pts continued to demonstrate no signs of radiographic OA

REVERSE PAO: CLINICAL RESULTS

OTHER OSTEOTOMIES

SALVAGE OSTEOTOMIES

• Full pre-operative work-up– assess degree of dysplasia and acetabular version

– assess femoral head neck offset

– assess labral pathology

• Select patients appropriately– symptomatic

– be aware of age

– no more than mild to moderate articular degenerative changes (Tonnis grade < 2)

– reasonable joint congruity (obtain functional xrays if necessary)

• Surgeon experience key to minimizing complications

SUMMARY