This document discusses techniques for total hip replacement in various hip disorders and conditions. It covers considerations for THR in arthritic conditions like osteoarthritis and rheumatoid arthritis, osteonecrosis, protrusio acetabuli, developmental dysplasia, post-traumatic disorders, failed reconstructive procedures, and infectious disorders. Key points emphasized include the need to modify surgical techniques based on individual conditions, risks like nerve injury or dislocation, and challenges like distorted anatomy that require special approaches.

1. THR in specific hip disorders
Dr.Ramkrishna Dahal
Ortho Resident

2. Contents
• Arthritic disorders
– OA
– RA
• Osteonecrosis
• Protrusio acetabuli
• Developmental dysplasia

3. Contents
• Post traumatic disorders
– Acute femoral neck fractures
– Failed hip fracture surgery
– Acetabular fractures
• Failed reconstructive procedure
– Proximal femoral osteotomy and deformity
– Acetabular osteotomy
– Arthrodesis and ankylosis

4. Contents
• Infectious diorders
– Pyogenic arthritis
– Tuberculosis
• Neuromuscular disorders

5. • Routine surgical techniques must be
modified to meet the needs of the various
conditions.

6. THR in Osteoarthritis
• MC indication for THR
• Shortening of extremity
• Hip is flexed, externally
rotated and adducted.
• Additional shortening
due to deformity.

7. • Difficulty in dislocation due to osteophytes.
• Adequate reaming: due to thick and hard
subchondral bone of the acetabulum.
• Osteophytes may completely cover the
pulvinar and obscure the medial wall.
• Failure to medialize the acetabulum may
leave the superior portion of the cup
unsupported or supported only by
osteophytes.

8. • Complete removal
of the osteophytes
is necessary to
avoid
impingement,
decreased range
of motion and
dislocation.

9. THR in Rheumatoid arthritis
• Medical issues
• Corticosteroids/immunosuppressive
medications
• Risk of fracture
• Risk of infection
• Femoral head erosion
• Some degree of acetabular protrusion

10. THR in Rheumatoid arthritis
• Anasesthetic complications
• Preparation of the femur is easy because
of the wide canal but cortex is thin and
easily fractured.
• Acetabulum: fractured medial wall.
• Severe osteopenia often makes
cementless fixation more difficult.
• Excessive femoral anteversion and
anterior bowing of the proximal femur
• Femoral osteotomy for extreme deformity.

11. • TKR can be technically difficult in the
presence of a markedly stiff hip.
• A severe flexion contracture of the knee
may predispose to dislocation of THR
• If involvement is equal THR should be
done first.

12. THR in osteonecrosis
• Patients usually between 24-45 yrs so
results are not as satisfactory as in older
age groups.
• Reactive hyperemia of capsule and
synovial tissue, thus hemorrhage.
• Large synovial effusion, simulate infection.
• Complete intramedullary removal of the
graft for good femoral fit.

14. Protrusio acetabuli

15. THR in protrusio acetabuli
• Medial migration of the femoral head beyond the
ilioischial line (Kohler).
• Deformity may progress until GT impinges on
the side of the pelvis.
• A/w varus deformity of the femoral head.
• Principles of reconstruction of protrusio
– Hip center in anatomical location to restore proper
joint biomechanics
– Intact peripheral rim to support acetabular component
– Remaining cavitary and segmental defects in medial
wall reconstructed with bone grafts

16. THR in protrusio acetabuli
• Risk of sciatic nerve injury.
• Difficult dislocation.
• Removal of small overhanging portion of
the posterior acetabular .
• Osteotomy of femoral neck.
• Adequate capsular release.
• Head extracted with corkscrew/piecemeal.
• Medial reaming is unnecessary.

17. THR in protrusio acetabuli
• Sloof et al technique of impaction grafting:
– Cancellous bone graft 0.5 to 1 cm tightly impacted
into the medial acetabular defects
– Segment of mesh wire is placed on the top of the
graft.
– A conventional acetabular acetabular component is
cemented into the construct.
• Slight lengthening of the limb due to prior varus
deformity.
• Low level femoral neck resection with enhanced
offset to minimize limb lengthening.

18. THR in developmental dysplasia
• Hypoplastic acetabulum.
• If more than 80% of the cup was covered
by host bone, morselized graft supero-
laterally.
• If the estimated cup coverage was
between 60% and 80%, structural grafting.
• If cup coverage was less than 60%, the
so-called cotyloplasty technique to reduce
the area of cup supported by the structural
graft.

20. THR in developmental dysplasia
• Small and deformed femoral head.
• Short and narrow femoral neck.
• Marked anteversion.
• GT is small and posterior.
• Femoral canal is narrow.
• Difficult canal preparation.

21. THR in developmental dysplasia
• Presence of false acetabulum.
• Poorly developed acetabulum.
• Transverse orientation of acetabulum.
• Extensive capsulotomy and tenotomy of
the psoas, rectus femoris and adductors
required to correct the deformity.
• Sciatic nerve stretch injury.

22. THR in developmental dysplasia
• In patients with UL dislocations, lengthening of
the affected extremity during surgery is
desirable.
• Shallow dysplastic acetabulum may require a
very small acetabular component (<40 mm).
• Placement of acetabular component in true
acetabulum rather than in false acetabulum.
– Limb lengthening
– Improves abductor function

23. THR in developmental dysplasia
• In Crowe 1: medialization of the floor of the
acetabulum provides adequate containment of
the standard component.
• In Crowe 2 and 3: a large superior segmental
deficit remains with a lack of superior coverage
of the component.
– Bulk acetabular bone grafting.
• In Crowe 4: very small acetabular component
placed in true acetabulum without structural
graft.
– When enlargement of acetabulum is required more
bone is resected from posterior wall.

24. THR in developmental dysplasia
• Femoral shortening osteotomy: reduction
without extensive soft tissue release.
• Osteotomy of greater trochanter: reduction
without undue tension on the sciatic nerve
or fracture of the femoral shaft.
• The bone should be resected 0.5 cm at a
time.
• Trial reduction attempted without undue
tension in soft tissue.

25. Post traumatic disorders

26. THR in Acute femoral neck
fractures
• Acceptable option in patients who are
– Living independently
– Fully ambulatory
– Mentally lucid
– Living an active lifestyle
• Specific measures to reduce incidence of
dislocations
– Switching from posterolateral to anterolateral
approach

27. THR in Acute femoral neck
fractures
• If posterior
approach is used,
use of large
diameter head
• Careful repair of
the posterior
capsule and short
external rotators.

28. THR in Acute femoral neck
fractures
The risk of dislocation:
– the surgical approach,
– the reconstruction of hip biomechanics,
– the head size and offset,
– the quality of capsular closure,
– the experience of the surgeon.
• Treatment of choice because of low revision rate
and better immediate function of hip.
• Abduction pillow for three to four days.
• Avoidance of >90 degree hip flexion and
adduction.

29. THR in failed hip fracture surgery
• Prolong non ambulatory patients due to
failed hip surgery.
• Dislocations and failure
• High mortality.
• In trochanteric nonunions, length of the
femur cannot be restored with a standard
implants.
• Calcar replacement stem.

30. THR in Acetabular fractures
• Preop CT
• Bony defect posteriorly in posterior wall
acetabulum fracture.
• Placement of acetabular components in
retroversion with subsequent dislocation.
• Either the acetabulum depeened for cup
support.
• Or the posterior wall grafted.
• For smaller contained defects, morselized
autograft.

31. • Nonunions of a displaced transverse
acetabular fracture: an antiprotrusio cage
with bone grafting.
• Difficult exposure due to scarring.
• Heterotopic ossification, complicated
exposure and impingement.

32. THR with antiprotrusio cage

33. THR in failed reconstructive
procedures
• In the presence of a previous proximal
femoral osteotomy that may have been
performed for slipped capital femoral
epiphysis (SCFE), Legg-Calvé-Perthes
disease, or developmental dysplasia of the
hip.

34. THR in failed reconstructive
procedures
• Proximal femoral osteotomy and deformity
– Presence of a plate can pose a technical
challenge during THA surgery
– Problem with inserting femoral stem in
deformed femur
– Displacement of fragments, dense cancellous
bone at the healed osteotomy site require
careful reaming.
– High speed burr to remove intramedullary
bone.
– distorted femoral architecture : hip instability.

35. THR in failed reconstructive
procedures
• Adequate capsular release and hip
dislocation should be done before
hardware removal.

36. • Acetabular osteotomy
– Distorted anatomy.
– Retroversion of the acetabulum.
– Careful positioning of the acetabular
component.
– Prior acetabular osteotomy had no
compromise in results of arthroplasty.
– Less acetabular augmentation was needed
compared with dysplastic hip.

37. • Arthrodesis and Ankylosis
– THR is indicated in a fused hip, with severe
persistent LBP, pain IL knee or CL hip, or in
pseudoarthrosis after failed arthrodesis.
– Conversion of arthrodesis into THR is safer
and easier if the trochanter is osteotomized.
– Adductor tenotomy may be required.
– Extremity ususally is lengethened.

38. THR in Infectious disorders

39. Pyogenic arthritis
• MRI 100% sensitive in showing the presence of
active infection in patients with prior
osteomyelitis.
• Infection status.
• Shortened limb with flexed and adducted hip.
• Deep scaring and sinuses.
• Complete sinus tract incision.
• Lack of sc tissues over the trochanter and in the
area of the proposed incision may require
rotation of a skin flap before THR.

40. Tuberculosis
• TB bacilli fewer in number in bone
infections than in infected sputum making
diagnosis TB osteomyelitis difficult.
• TB bacilli has little biofilm and adheres
poorly to implants.
• Reactivation of TB infections after THR
can be treated with debridement and drug
therapy with retention of the prosthesis.

41. • If GT and subtrochanteric areas resected, hip
will be unstable because reattaching the
abductor muscle is difficult.
• An extra long femoral component is necessary.
• Custom made components and segmental
replacement stem can be used.
• Gluteal muscles are sutured to holes made in
the component for this purpose.
• Acetabulum can be reconstructed with cement
with reinforcement ring or cage.

42. THR in Neuromuscular disorders
• Combined flexion and adduction
contractures are common, but their
presence may not be appreciated when a
patient has an acute fracture.
• An anterior or anterolateral approach is
preferable in these patients.
• Release of the anterior capsule, psoas,
adductor tenotomy all may be required.
• Placement of acetabular component in
anteversion.

43. Take Home Messages
• Identifying problems.
– Soft tissue
– Bony
• Preop planning
• Risk assesment
• Possible implant and prosthesis choice

44. Thank you
Next presentation by Dr Manoj
Hip preserving surgeries