Do Double-fan Surgical Helmet Systems Result in Less Gown-particle Contamination Than Single-fan Designs?

BACKGROUND: Surgical helmet systems commonly are stand-alone systems with a single fan blowing air into the suit, creating positive pressure that blows particles out through areas of low resistance, possibly contaminating surgical attire and the surgical field. Two-fan systems were developed more recently to release spent air, also theoretically lowering pressure in the suit and decreasing the aforementioned risk of particle contamination. To our knowledge no study to date has measured the potential differences in gown particle contamination to support this hypothesis. QUESTIONS/PURPOSES: We compared a commonly used single-fan system versus a two-fan system and asked: (1) Which fan system results in less gown particle contamination? (2) Are there differences between the systems in the location of contamination? METHODS: Using an existing experimental study model, two surgeons performed five 30-minute TKA simulations comparing a single-fan to a double-fan helmet system after applying fluorescent powder to the hands, axillae, and chest. Both are two-piece hood and gown systems. The single-fan sits on top of the helmet blowing air into the suit; the double-fan system has a second fan positioned at the rear blowing out spent air. Ultraviolet light-enhanced photographs were subsequently obtained of the flexor and extensor surfaces of the arms, axillary areas, and front and back of the chest. We chose these locations because they all contain either a seam or an overlap between gown and hood or gloves through which particles can escape. The images were scored for contamination on a scale of 1 (zero specks) to 4 (> 100 specks) by three independent observers. Interobserver correlation was assessed through Spearman's test yielding 0.91 (95% CI 0.86 to 0.94; p < 0.0001), 0.81 (95% CI 0.73 to 0.87; p < 0.0001) and 0.87 (95% CI 0.80 to 0.91; p < 0.0001) between observers 1 and 2, observers 1 and 3, and observers 2 and 3, rendering the used scale reliable. Results of the observers were averaged and compared using the Mann-Whitney U test. RESULTS: There was no difference in overall gown particle contamination between the systems (overall single-fan median contamination score 2.5 of 4 [interquartile range Q1-Q3 0-3.42] versus double fan 1 out of 4 (Q1-Q3 0-3); p = 0.082), but all tests showed there was contamination at the gown-glove interface. In general, there were few differences between the two systems in terms of location of the contamination; however, when comparing only the axillary regions, we found that the single-fan group (median score 3.67 [Q1-Q3 3-4]) showed more contamination than the double-fan group (2.33 [Q1-Q3 0-3.08]); p = 0.01. CONCLUSION: We found no difference in gown particle contamination between a single-fan and a double-fan helmet design. However, we note that contamination was present in all tests with both systems, so surgeons should not assume that these systems provide a contamination-free environment. CLINICAL RELEVANCE: When using such helmets, the surgeon should not place items close to the axillary region because the seam of the gown may have low resistance to particle contamination. Gown designs could be improved by creating better seals, especially at the arm-body seam.

Revision of a tibial baseplate using a customized oxinium component in a case of suspected metal allergy. A case report.

Materials currently used for total knee arthroplasty (TKA) are well known for their good biocompatibility, but corrosion of the implant and metal ion release may elicit an immune response in the periprosthetic tissue. Its role in the outcome of the implant remains a subject of discussion. Metal sensitivity after joint replacement is frequent, but few patients exhibit symptoms. Nickel, cobalt and chromium are the most common sensitizers, but allergic reactions to titanium and vanadium have also been described. We present a case of a 46-year old woman with persistent dermatitis following TKA revision with an oxidized zirconium (oxinium) femoral component and Ti6Al4V tibial baseplate. After revision with a customized oxinium tibial component, symptoms resolved completely.

Mucoid degeneration of the anterior cruciate ligament.

Mucoid degeneration of the anterior cruciate ligament (ACL) is a rare cause of knee pain. We report a case of a patient with mucoid degeneration of the ACL, presenting with posterior knee pain and no history of a major knee trauma. On clinical examination, the active range of motion showed a flexion deficit. The posterior knee pain was induced by passive hyperflexion of the knee. There was no evidence of ligamentary instability. MRI showed a diffuse thickening of the ACL with a nodular mass on the femoral insertion occupying the intercondylar notch, with increased signal intensity on both T1- and T2-weighted images. Arthroscopic evaluation showed a diffuse hypertrophy of the ACL, throughout the entire length of the posterolateral bundle (PLB). A yellowish homogenous mass on the femoral insertion of the ACL impinged on the posterior cruciate ligament (PCL) in flexion and occupied the entire intercondylar notch. We performed an arthroscopic debridement of the hypertrophied tissues as precisely as possible. This resulted in a nearly complete removal of the PLB and immediate relief of symptoms. Examination of knee stability after debridement showed a stable ACL. Arthroscopic debridement of the mucoid degeneration of the ACL proved to be a safe and effective method, without causing ligamentary instability in daily activities.

Percutaneous plate fixation of fractures of the distal tibia.

Minimally invasive plate osteosynthesis (MIPO) of the distal tibia offers several theoretical advantages compared to classic open reduction and internal fixation. A mechanically stable fracture-bridging osteosynthesis can be obtained without significant dissection and surgical trauma to the bone and surrounding soft tissues. In this retrospective study we looked at the results and complications in ten consecutive patients treated with percutaneous plating for fractures of the distal tibia and plafond with a minimum follow-up period of one year. No significant soft tissue problems occurred. The need for bone grafting should be carefully evaluated in every case as we encountered two delayed unions. All fractures healed within one year; there was no fracture malunion. The use of indirect reduction techniques and small incisions to insert hardware is technically more demanding and requires strict radioscopic control throughout the procedure, but it considerably decreases surgical trauma to the soft tissues.