Revision Total Hip Arthroplasty

1. Revision Total Hip Arthroplasty • Requires a clear preoperative plan. • Plan - 1) Revision Dx. 2) Surgical approach 3)Instruments 4) Bone Grafts 5) Implants • Preparation to handle unexpected problems that may require a greater exposure .

2. Surgical Approach • Revisions performed with posterior approach • May be extended proximally or distally • Proximal extension exposes entire ilium and anterior column

3. Trochanteric Osteotomy • Most common extensile measure • 4 types: 1)Extended trochanteric slide 2)Simple trochanteric slide 3)Conventional trochanteric osteotomy 4)Extended conventional osteotomy

4. Factors for Choice of Osteotomy • Bone quality • What needs to be exposed

5. Indications for Extending Length • Greater trochanter compromised by osteopenia or osteolysis - osteotomy lengthening ensures adequate amount of lateral bone for fixation • Proximal medial bone loss - osteotomy extended into diaphysis so adequate medial bone is available for wire or cable fixation of the osteotomy

6. Need for Increased Exposure • Osteotomy choice is based on the required exposure • Anterior trochanteric slide - exposes metaphysis of femur to the level of the lesser trochanter • Conventional trochanteric - metaphysis of femur with improved acetabular, anterior wall, and ilium exposure

7. Cont. • Extended trochanteric slide - acetabular exposure of simple anterior trochanteric slide with better femoral exposure • Extended conventional osteotomy - maximizes exposure of femur and acetabulum

8. Revision Surgical Approach • Posterolateral • Previous incision is posterolateral or direct lateral - use the same incision • New incision - landmarks are halfway b/w anterior and posterior borders of greater trochanter to allow more anterior exposure

9. New Incision (cont.) • Upper half - parallel to fiber of gluteus maximus • Lower half - longitudinal extension toward the knee • Gluteus Maximus insertion to femur is released to expose sciatic nerve - failure to do so increases the risk of constriction of the nerve by retraction

10. Revision Surgical Approach (cont.) • Retained femoral component - anterior capsule is divided to effect anterior displacement of the femur. • Iliopsoas tendon sheath is entered to define plane and the capsule is divided from the inside out, starting distally at the lesser trochanter > retractor placed over acetabulum to displace femur anteriorly

12. Anterior Trochanteric Slide • Indications • Femoral - 1) removal of well-fixed proximal porous coated prosthesis 2) removal of failed endoprosthesis with bone fenestrations. Anterior and posterior femoral components can be reached with a osteotome

13. Anterior Trochanteric Slide (cont) • Acetabular - 1) acetabular protusio without easy dislocation 2)acetabular revision cases with femoral component retention. • Small size of trochanteric fragment limits indications: 1) If acetabular revision results in leg lengthening, fragment may not reach femoral bone for attachment. 2) Absence of medial bone for securing wires of cables.

14. Technique for Anterior Trochanteric Slide • 1) Posteriolateral approach extended 2 inches distally • 2) elevate posterior border of vastus lateralis to the greater trochanter • 3) expose gluteus medius by external rotation • 4) Develop plane between gluteus medius and gluteus minimus

15. Technique (cont.) • 5) Osteotomy performed in internal rotation with distal margin below insertion of the v. lateralis, and the superior margin lateral to the piriformis fossa b/w the medius and minimus insertions. • 6) Reattach the tochanteric fragment with 18 gauge wires or cables through or below the lesser trochanter and through the greater trochanter

17. Extended Conventional Trochanteric Osteotomy • Indications - Extensive acetabular bone stock damage and difficult acetabular revisions where excessive leg lengthening can occur. • Contraindications - Retention of a well fixed femoral component

18. Technique • 1) Distal margin - 5 cm. Distal to the greater trochanter on the lateral femoral shaft • 2) Proximal margin - exits the greater trochanter between the gluteus medius and superior hip capsule • 3) Vastus lateralis is stripped • 4) Internal rotation - isolate posterior margin of gluteus medius

19. Technique (cont.) • 5) External rotation - isolate anterior margin of gluteus medius • 6) Osteotomy cuts are made through lateral half of periosteal surface and lateral third of endosteal surface • 7) Reflect osteotomy with care to protect inferior gluteal nerve • Repair with 2 wires or cables

20. Post-Operative Rehabilitation • Based on the stability of trochanteric attachment • ROM limitations determined intraoperatively • Fixation strength of trochanter is determined by stressing the trochanter with adduction and ROM • FWB @ 3 months

21. Rehab (cont.) • PROM without adduction within the recorded limits of hip stability recorded intraoperatively • No hip flexion or adduction for 6 weeks

23. Vascular Schaphoid Window for Access to Femoral Canal In Revision THA Jeff Easom, D.O. Garden City Hospital

24. Introduction • Removal of distal cement from femoral canal involves substantial risks of canal perforation • Cement removal that extends beyond apex of anterior femoral bow may not be possible • cortical perforation increases the risk of later femoral fracture

25. Measures taken are controlled windows and extended osteotomies.

26. Femoral Windows • Muller - 1cm X 20cm anterior gutter • Nelson and Weber - Lateral rectangular window 2cm wide x 6cm long • Sydney and Mallory - Serial 9 mm perforations to guide instruments and afford access for punches to remove broken stems - 9 post-op frxs. Of 219 cases

27. Femoral Windows (cont.) • Shepherd and Turnbull - 1 cm by 2 cm window on the anterior surface of femur b/w 3.2mm drill holes without replacement fixation - early healing and good results • Klein and Rubash - Shepherd window creations with size of 2 cm by 5 cm - complete detachment from soft tissue with fixation by cerclage wires - mean healing 17 weeks and no post-op fractures.

28. Extended Femoral Osteotomy • Extension of a trochanteric osteotomy distally along femoral shaft • Peters and Assoc. - good results • Younger and Assoc. - 20 cases with extended osteotomy of greater trochanter with 1/3 of cortical diameter of the femur hinged anteriorly with preservation of blood supply by soft-tissue attachments-healing @ 3 months

29. Advantages • Ease of component and cement extraction • Superior visualization of the distal femoral canal, which allows mor accurate preparation of distal femur and eliminates varus placement of revision implant.

30. Advantages (cont.) • Anterolateral, posterior, or combined approaches to hip joint itself may be implemented

31. Vascularized Schaphoid Window Technique • Lateral incision 30 degrees posteriorly proximal to the greater trochanter • Extend incision to beyond distal extent of proposed osteotomy • elevate vastus lateralis width of 1cm to expose lateral femur - maintains blood supply by muscular attaachments

32. Technique (cont.) • Scaphoid osteotomy - Through both cortices of femur lateral to medial with incorporation of smooth rounded edges. • Avoid muscle stripping • Replace with 1 or more cerclage wires • Reimplantation devices should bypass the window by @ least 2 cortical diameters with protected weightbearing for 12 weeks.

33. Conclusion • Combines the advantages and avoids the disadvantages of other osteotomies. • Afford an approach that give excellent exposure of the femoral canal over whatever length is require for safe implant and cement removal • Permits all reconstructive possibilities and minimizes risk of complicaitons (nonunion of window and fracture).