Revision Hip Arthroplasty Case Title: Revision THA Using Impaction Bone Grafting for the Socket and Stem for Aseptic Loosening

 

Case Title: Revision THA Using Impaction Bone Grafting for the Socket and Stem for Aseptic Loosening

Polyethylene-induced osteolysis with severe socket bone loss Paprosky type 2B and femoral

bone loss Paprosky 3A. There is also proximal femoral dilatation and ballooning thinning the cortex and risking fracture. The acetabular site was reconstructed using a marginal roof mesh to contain the small defect followed by impaction grafting of the acetabular bed and accepting a cemented HXLP (Stryker). The femur was pro-phylactically wired to prevent a fracture from hoop stresses, and a long 205 mm and 44 mm offset cemented Exeter stem (Stryker) was inserted using the third-generation cementing technique. The reason for selecting impaction allografting for reconstructing the femur was based on patient’s young age. Biological reconstruction is occasionally preferable for young individuals pending on contained and reconstructable defects (Fig. 18.2).

 

 

 

 

Fig. 18.2 (a, b) Preoperative AP and Lateral x-rays of the left hip (c) bone chips used for the acetabular impaction grafting and (d) postoperative x-ray of the left hip

 

1. Case Title: Re-revision THA Acetabulum Paprosky 2A Defect Using Impaction Grafting and Constrained Liner

    

    

    

   1. Demographics

       

      Age: 79 Sex: Male BMI: 30

       

   2. Relevant Past Medical History

       

      Principal pathologies: arterial hypertension, dyslipidaemia, prostate hyperplasia.

      Previous surgical procedures: AMIS primary two years back, acetabular component loosening six months postoperatively, the first revision to a

      larger uncemented socket and head to increase stability. Injury to abductors and positive Trendelenburg.

      Medication: b-blockers and statins.

      History of presenting complaint: pain and limping following revision procedure.

       

   3. Clinical Examination

       

      Symptoms: pain and instability due to positive Trendelenburg.

      Range of motion: full ROM but painful, unable to abduct further to 20°.

      Specific tests: unable to stand on the left leg.

      Scoring: HHS 70.

      Neurovascular evaluation: left hip abductor wasting injury to the superior gluteal nerve during the first revision procedure.

       

   4. Preoperative Radiological Assessment/Imaging

       

       

       

      Fig. 18.3 Contained defect but medial wall compromise that could be classified as Paprosky 2B (medial wall absent but periphery intact)

       

   5. Preoperative Planning

       

      Diagnosis: loose left acetabular component Paprosky type 2A defect contained but medial wall absent (Fig. 18.3).

      Possible treatment options: revision acetabulum using impaction grafting.

      Chosen treatment method: medial wall mesh Stryker X-change SM, screws for mesh (4 × 35 mm,1 × 25 mm), impaction allografting and constrained cemented acetabular insert Stryker Trident 50 mm and femoral head 28 mm metal.

      Selection of implants if applicable and rational: re-revision with instability and positive Trendelenburg. A constrained liner was available to use.

      Strategies to overcome difficulties: joint aspiration performed prior to surgery and microbiology testing send ten days before the revision. No microorganisms were grown over a 10-day enhanced culture. A bone scan Tc-99 m was performed that reviled loosening of the acetabular component and a subsequent Indium-111 WBC scintigraphy confirmed aseptic loosening alone.

       

   6. Surgical Note

       

      With the patient in lateral decubitus position and a posterior approach, the hip was exposed. Six samples were sent for microbiology testing including soft and bone tissues. The stem was found solidly fixed. The femoral head was easily removed, and then the composite stem femur was retracted anteriorly behind the anterior retractor. The greater trochanter was denuded entirely from the abductors solidifying our original decision for the use of a constrained liner. The exposure and the removal of the loose acetabular component was easy. The acetabulum was then accessed for its congruency. The ream was intact though deformed in places, and the medial wall was compromised significantly. Reaming with subsequent reamers was performed until the cancellous bone was exposed up to size 54 mm. Impaction allografting was elected to be performed. An octopus-shaped medial wall mesh of medium size (Stryker)

      was placed on top of the medial wall defect and stabilized with two peripheral screws. The roof was reinforced with a small marginal roof mesh (Stryker) and screws. Impaction acetabular grafting using morselized large 1 cm washed out cheeps was performed with the special impactors until the cavity on top and medial was filled with new cancellous and stable allograft. Stability was manually tested. Then a trial reduction using a trial constrained liner was performed to adjust for the leg length and stability. Then a cemented constrained component size 50 mm (Stryker) was cemented into the grafted socket using third-generation cementing technique (Fig. 18.4 a, b).

       

   7. Postoperative Radiographs

      (Fig. 18.4)

       

       

      a

      b

       

       

      Fig. 18.4 (a) Medial wall mesh and marginal mesh on the roof. Impaction grafting and constrained liner. Leg length equal after reduction. (b) Intraoperative picture

       

   8. Postoperative Management

       

      Chemoprophylaxis and anticoagulant treatment period: vancomycin 500 mg (one dose preoperatively and two doses postoperatively), cefuroxime 750 mg (one dose preoperatively and two doses postoperatively), enoxaparin 1 × 1 for the days of hospitalization then rivaroxaban 10 mg 1 × 1 for thirty days

      Gait/limb loading until full loading: partial weight bearing for six weeks and then weight bearing as tolerated.