A patient who has early or late polyethylene wear debris occurring after a cemented or cementless primary total hip arthroplasty (THA) may be asymptomatic or may have groin pain, component loosening, or pathologic fracture.1,7 Polyethylene wear debris may cause a periarticular or intrapelvic mass mimicking a gynecologic mass5,8,9,14 or a soft tissue tumor,2,13 or may cause deep vein thrombosis,10,15 lower extremity edema,3 ureteral or bladder compression,5,6 or sciatic neuropathy.4
I report a patient with late polyethylene wear debris who presented with a large thigh mass 12 years after cementless revision THA.
A 60-year-old man presented for a routine 12-year followup of his right revision THA. He reported a slowly enlarging thigh mass since the previous year. The patient had revision of a loose cemented THA 12 years before presentation with an extra large (66 mm) cementless acetabular component (HGP-I, Zimmer, Warsaw, IN) and a cementless proximally porous-coated femoral component (ABR, Zimmer). When seen at followup 11 years after surgery, the patient had slight, occasional hip pain and a slight limp. There was no thigh mass. At routine followup 1 year later, the patient reported only slight, occasional hip pain, and walked only short distances outdoors because of pulmonary problems related to chronic sarcoidosis. The index cemented THA had been performed for osteonecrosis related to steroid use for sarcoidosis. Physical examination showed a moderate right hip limp and a nontender, soft right proximal anterolateral 13 × 1-cm thigh mass (Fig 1). Radiographs showed no component loosening but small osteolytic lesions in the superior acetabulum (Fig 2). There was no loosening or osteolysis of the femoral component. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were normal. Computed tomography (CT), before and after intravenous contrast, showed an approximately 15 × 8 × 6-cm mass with fluid intensity in the lateral quadriceps (Fig 3). The radiologist did not detect communication of the mass with the hip or proximal femur. No abnormal enhancement was seen in the mass. Aspiration of the thigh mass yielded 225 mm of thick yellow fluid. Microscopic evaluation showed greater than 175,000 nucleated cells and macrophages with inclusions. Cytopathologic examination identified oil red O positive-staining material in macrophages, consistent with polyethylene wear debris. Routine and fungal cultures showed no growth. An acid-fast bacillus (AFB) culture was not performed. The fluid-filled mass recurred within 10 days. The patient was diagnosed with a thigh pseudotumor from polyethylene wear debris. Reoperation was recommended despite the minimal symptoms because the fluid-filled mass recurred after aspiration.
Intraoperatively, a small hole in the posterior inferior pseudocapsule communicated with the thigh mass located between the rectus femoris and vastus lateralis. Three hundred milliliters of fluid were aspirated and the cyst wall was excised with electrocautery. The author's protocol during liner exchange is to remove only loose acetabular screws and three of the four acetabular screws were rigidly fixed. The femoral component was not loose on manual testing. The 28-mm polyethylene liner and head were exchanged for a 32-mm highly cross-linked polyethylene liner (Longevity, Zimmer), and 32-mm diameter head and 3.5-mm neck to retain equal leg lengths.
Pathologic examination showed a 15 × 5-cm tissue mass with golden discoloration of the inner surface. Microscopic examination was reported as joint capsule with macrophage infiltrate and polarizable material. Routine bacteriologic culture only was performed and showed no growth. Fungal and AFB cultures were not performed.
Postoperatively, the patient wore a hip orthosis for 6 weeks to prevent dislocation but was allowed full weight-bearing. At the 1-year followup, the patient had slight, occasional barometric hip pain, walked without a limp only short distances because of respiratory problems from sarcoidosis. There was no recurrence of the thigh mass. A hip radiograph showed no loosening of the acetabular component (Fig 4).
A thigh mass is a rare late complication of THA. Sizable masses around the hip from polyethylene wear debris can extend intrapelvically directly through the pelvis8 or via the iliopsoas bursa.15 Complications may include bladder compression, symptomatic deep vein thrombosis, and severe lower extremity edema from vascular compres-sion.3,6,9,10,15
Schmalzried et al described the concept of the “effective hip joint space,” in which any tissue compartment close to the prosthesis and accessible to joint fluid should be considered a part of the prosthetic hip.12 Joint fluid containing polyethylene wear debris is transported down the path of least resistance through bone or soft tissue interspaces, usually leading to periprosthetic osteolysis and component loosening. The small hole in the postero-inferior hip capsule provided the path of least resistance to the thigh compartment between the rectus femoris and vastus lateralis muscles. The acetabular and femoral components were well fixed and there was only minor acetabular osteolysis. Treatment with liner and head exchange with excision of the thigh mass was successful.
There is one report of a 7-cm diameter thigh mass adjacent to a loose cemented titanium alloy femoral component.11 This patient had thigh pain; radiographs showed loosening of the femoral component with lateral cortical destruction at the tip of the stem. The mass, adjacent to the cortical destruction, contained metal, cement, and polyethylene particles. Cortical destruction of the femur occurs when cemented femoral components loosen. In my patient the implants were well fixed and the thigh mass was located away from the femoral diaphysis.
The differential diagnosis of a thigh mass developing late after primary or revision THA should include tumor, infection (abscess), or polyethylene wear debris. Computed tomography should be performed to determine if it is a solid or fluid-filled mass. Measuring ESR and CRP and possible aspiration of the thigh mass and prosthetic hip should be considered to screen for infection. Plain radiographs may disclose eccentric head location in the acetabulum indicating severe wear or periacetabular osteolysis. Surgical treatment of a symptomatic patient with a pelvic or thigh mass from polyethylene wear may be considered, with liner exchange and excision of the debris-filled mass if the components are well fixed. However, if the polyethylene wear and mass are associated with component loosening, then revision of the components is necessary. If the patient is elderly or in frail health with a minimally symptomatic mass, observation may be appropriate.5
1. Archibeck MJ, Jacobs JJ, Roebuck KA, Glant TT. The basic science of periprosthetic osteolysis. J Bone Joint Surg Am
2. Brand RA, Marsh JL. Particulate debris osteolysis simulating malignant tumor. Iowa Orthop J
3. Butler RA, Barrack RL. Total hip wear debris presenting as lower extremity swelling: a report of two cases. J Bone Joint Surg Am
4. Fischer SR, Christ DJ, Roehr BA. Sciatic neuropathy secondary to total hip arthroplasty wear debris. J Arthroplasty
5. Hananouchi T, Saito M, Nakamura N, Yamamoto T, Yonenobu K. Huge pelvic mass secondary to wear debris causing ureteral obstruction. J Arthroplasty
6. Hattrup SJ, Bryan RS, Gaffey TA, Stanhope CR. Pelvic mass causing vesical compression after total hip arthroplasty: case report. Clin Orthop Relat Res
7. Jacobs JJ, Shanbhag A, Glant TT, Black J, Galante JO. Wear debris in total joint replacements. J Am Acad Orthop Surg
8. Jeanrot C, Ouaknine M, Anract P, Forest M, Tomeno B. Massive pelvic and femoral pseudotumoral osteolysis secondary to an unce-mented total hip arthroplasty. Int Orthop
9. Mak KH, Wong TK, Poddar NC. Wear debris from total hip arthroplasty presenting as an intrapelvic mass: case report. J Arthro-plasty
10. Morrison KM, Apelgren KN, Mahany BD. Back pain, femoral vein thrombosis, and an iliopsoas cyst: unusual presentation of a loose total hip arthroplasty. Orthopedics
11. Patterson P, Grigoris P, Raby N, Reid R. A thigh mass associated with a total hip replacement in a 69-year-old woman. Clin Orthop Relat Res
12. Schmalzried TP, Jasty M, Harris WH. Periprosthetic bone loss in total hip arthroplasty: polyethylene wear debris and the concept of the effective joint space. J Bone Joint Surg Am
13. Sporer SM, Bernini PM. Extensive periacetabular osteolysis presenting as a mass on rectal examination: a case report. J Bone Joint Surg Am
14. Thienpont E, Vernaeve H. Reactive pelvic cyst following total hip arthroplasty: a case report. Acta Orthop Belg
15. Yang SS, Bronson MJ. Cystic enlargement of the iliopsoas bursa causing venous obstruction as a complication of total hip arthroplasty: a case report. J Arthroplasty