Persistent Synovial Fistula After Arthroscopy: Is Titanium Synovitis a Risk Factor?

Abstract

Synovial fistulae after arthroscopy and titanium-induced synovitis of the knee are both uncommon. We report a case in which a persistent fistula led to frank infection after a diagnostic arthroscopy during which a florid titaniuminduced synovitis of the knee had been discovered. We are not aware of any previous reports of this association. Case report. A 66-year-old man was admitted with pain and locking of his left knee two years after insertion of a Brigham unicondylar prosthesis for medial compartment osteoarthritis. The pain was worse around the patella and exacerbated by movement and weight-bearing. Radiographs were satisfactory apart from the presence of a cement loose body, and the WBC and ESR were normal. The provisional diagnosis was either mechanical impingement due to the loose body or patellar maltracking.Arthroscopy showed a florid black-stained titaniuminduced synovitis with a large quantity of metal debris in the synovial fluid. The polyethylene of the tibial component was completely worn, allowing metal-to-metal articulation at the tibiofemoral joint. The central part of the metal tibial tray had also worn through ( Fig. 1). Synovial biopsy showed a giant-cell granulomatous reaction due to titanium oxide.A decision was made to revise the knee arthroplasty in a few weeks, but the medial parapatellar portal failed to heal and became a persistent and troublesome synovial fistula (Fig. 2). This discharged black-stained sterile fluid for over three months and was complicated by a frank staphylococcal septic arthritis. Treatment by joint lavage and longterm antibiotic therapy was required before the infection settled. The knee revision was eventually performed using antibiotic-loaded cement. A blood test one week later showed a markedly raised titanium level of 420 g/l (normal ≤8 g/l) indicating titanium metallosis. Discussion. The incidence of persistent synovial fistula after arthroscopy is very low. Bamford et al (1993) reported only one case in 8500 arthroscopies. In our patient a large amount of titanium debris had been generated by the wearing of the chrome-cobalt femoral component of the Brigham prosthesis through the titanium tibial tray. The chronic effusion caused by the titanium particles may have resulted in persistent leakage of fluid which prevented healing, or the particulate titanium may have acted as a wound irritant. Whatever the exact mechanism, we are not aware of any previous report of an association between metal-induced synovitis and fistula formation.Without arthroscopy, a high index of suspicion is required to make the diagnosis of metal-induced synovitis. Other disorders, such as aseptic loosening, are a much more common cause of pain after knee arthroplasty. Weissman et al (1991) found that the presence of a dense line outlining a portion of the capsule (the so-called metal-line sign) was 322 BRIEF REPORTS Fig. 1 Fig. 2

The Use of Regional Flaps for the Repair of Synovio-Cutaneous Fistulas of the Shoulder after Attempted Rotator Cuff Repair: A Report of Two Cases

“…Similar to prior studies that detailed fistula tract formation in the knee secondary to an underlying surgical site infection or facial dehiscence, it is likely that the fistulous tract developed in our patients' secondary to a either a postoperative infection or inflammation and necrosis of the rotator cuff tendons and tissues surrounding the glen humeral joint [8, [18][19][20][21][22]. In both of our reported cases, the deltoid fascia was noted on perioperative imaging and intraoperative exam to be markedly dehisced and unsuitable for primary closure.…”

“…The knee is the most commonly reported location to develop synovia-cutaneous fistulas following arthroscopic surgery, with an incidence of 0.5% to 1% [15][16][17]. In general, these patients respond well to immobilization of the knee or surgical excision of the fistulous tract and primary closure [8, [15][16][17].…”

“…In general, these patients respond well to immobilization of the knee or surgical excision of the fistulous tract and primary closure [8, [15][16][17]. Similarly, of the available cases of synovia-cutaneous fistula reported in the shoulder, most have been managed with debridement and primary closure.…”

“…Similarly, of the available cases of synovia-cutaneous fistula reported in the shoulder, most have been managed with debridement and primary closure. In the setting of an underlying infection, primary closure of a synovia-cutaneous fistula is associated with higher rates of failure, prompting the use of a regional flap for successful wound coverage without recurrence of the fistula or abscess formation [18][19][20][21][22].…”

Persistent synovial fistula after athroscopy in carbon synovitis

“…Dandy and O’Carroll reported one case in 1000 arthroscopies 5 while Sherman et al noted had no fistula formation in 2640 cases 6 . Recently Li et al reported a case following diagnostic arthroscopy in a unicondylar knee replacement 7 . They suggested titanium‐induced synovitis as a possible cause for the development of synovial fistula.…”