Optimizing lavage during knee arthroscopy: a three-dimensional MRI study.

PURPOSE: To determine the best positioning and the resulting fluid flow patterns inside the knee during arthroscopy, reducing the surgical morbidity associated with the arthroscopic irrigation and debridement of a septic knee joint. MATERIALS AND METHODS: Three-dimensional MRI, using an MRI-compatible human cadaveric knee arthroscopic model, generated fluid flow diagrams and velocity vector data. This was analyzed for six different arthroscopic configurations and at six different locations within the knee joint. RESULTS: At any one static arthroscopic position, fluid flow velocity differed at the various locations in the knee, often with statistically significantly greater flow at one location over another. In general, flow was greatest at the location at which the inflow cannula terminated and preferentially flowed directly to the outflow cannula location, neglecting spaces in the knee that were not on this direct path. Three-portal arthroscopy provided no benefit over two-portal arthroscopy. CONCLUSION: To maximize arthroscopic lavage throughout all compartments in the knee, the arthroscopist must individually enter each space in the knee. Static arthroscopy in the setting of knee sepsis may lead to inadequate flow in certain areas of the knee and may lead to treatment failure. Three-portal arthroscopy does not improve lavage efficiency.

Hip arthroscopy in adults.

The acceptance and rates of hip arthroscopy are increasing in the United States and abroad and the literature describing it is expanding. Indications for hip arthroscopy include labral tears, loose bodies, femoroacetabular impingement, ruptured ligamentum teres, chondral injuries, adhesive capsulitis, instability, synovial disease, disorders of the iliopsoas tendon, external coxa saltans, tears of the hip abductors, and diagnosis of unresolved intra-articular hip pain. Current techniques in the central and peripheral compartments include, but are not limited to, labral debridement, labral repair, chondroplasty, microfracture, synovectomy, loose body removal, acetabuloplasty, proximal femoral osteoplasty, and iliopsoas release, with other procedures possible in the peritrochanteric space. Long-term outcomes are limited, but early data shows good results for many arthroscopic procedures in the hip when they are performed in the absence of degenerative disease. Improved techniques and technology are allowing for more advanced procedures to become popularized, but long-term outcome data about hip arthroscopy is still relatively sparse.

Detection of traumatic arthrotomy of the knee using the saline solution load test.

BACKGROUND: The saline solution load test helps to determine if a wound extends into the knee joint. Little is known about the volume of injected intra-articular saline solution that is needed to effectively rule in or rule out a traumatic arthrotomy of the knee. The purpose of the present study was to determine the appropriate volume and needle location for the diagnosis of a traumatic knee arthrotomy and to assess the effect of associated variables, including knee circumference, body mass index, and sex. METHODS: Fifty-six consecutive patients scheduled for knee arthroscopy were enrolled. A standard inferolateral arthroscopic portal was made with a single stab incision with use of a number-11 blade. Injection sites were randomized to either a superomedial or inferomedial location. The injection of normal saline solution at a rate of 5 mL/sec through an 18-gauge needle was continued while the knee was moved through a range of motion until fluid extravasated from the iatrogenic laceration. The volume of injected fluid was recorded. RESULTS: The study group included thirty-one female patients and twenty-five male patients with a combined average age of fifty years and an average body mass index of 30.9. In order to effectively diagnose 50% of the arthrotomies, 75 mL of injected fluid was needed; the volumes that were needed in order to effectively diagnose 75%, 90%, 95%, and 99% of the arthrotomies were 110, 145, 155, and 175 mL, respectively. The mean volumes of injected fluid needed for a positive result at the inferomedial and superomedial needle locations were 64.0 and 95.2 mL, respectively; this difference was significant (p = 0.01). There was no correlation between necessary injection volume and sex, body mass index, or knee circumference. CONCLUSIONS: In order to detect 95% of 1-cm inferolateral arthrotomies of the knee with use of the saline solution load test, 155 mL must be injected. An inferomedial injection location requires significantly less fluid than a superomedial injection location does for the diagnosis of inferolateral arthrotomies of the knee.

Cold exposure injuries to the extremities.

Cold exposure injuries comprise nonfreezing injuries that include chilblain (aka pernio) and trench, or immersion, foot, as well as freezing injuries that affect core body tissues resulting in hypothermia of peripheral tissues, causing frostnip or frostbite. Frostbite, the most serious peripheral injury, results in tissue necrosis from direct cellular damage and indirect damage secondary to vasospasm and arterial thromboses. The risk of frostbite is influenced by host factors, particularly alcohol use and smoking, and environmental factors, including ambient temperature, duration of exposure, altitude, and wind speed. Rewarming for frostbite should not begin until definitive medical care can be provided to avoid repeated freeze-thaw cycles, as these cause additional tissue necrosis. Rewarming should be rapid and for an affected limb should be performed by submersion in warm water at 104 degrees to 107.6 degrees F (40 degrees to 42 degrees C) for 15 to 30 minutes. Débridement of necrotic tissues is generally delayed until there is a clear demarcation from viable tissues, a process that usually takes from 1 to 3 months from the time of initial exposure. Immediate escharotomy and/or fasciotomy is necessary when circulation is compromised. In addition to the acute injury, frostbite is associated with late sequelae that include altered vasomotor function, neuropathies, joint articular cartilage changes, and, in children, growth defects caused by epiphyseal plate damage.

Threaded cortical bone dowels in lumbosacral arthrodesis: a review.

Lumbar fusion is a common spinal surgery, for which numerous devices have been developed to aid in segment stabilization. A threaded cortical bone dowel is a machined and processed bone allograft which is one such development. Threaded cortical bone dowels are attractive because of their osteoconductive nature and the opportunity to load them with osteogenic morselized bone autograft or osteoinductive growth factors, such as bone morphogenetic proteins. Although threaded cortical bone dowels have been in clinical use for more than 5 years, they have not been the subject of a comprehensive review. The current article covers the history, preparation, uses, safety, and efficacy of threaded cortical bone dowels in lumbosacral interbody fusion.