Gregory J. Lane

Simultaneous bilateral versus unilateral total knee arthroplasty. Outcomes analysis.

One hundred consecutive, primary simultaneous bilateral total knee arthroplasties were prospectively compared with 100 consecutive, primary unilateral total knee arthroplasties in reference to relative risk, complications, cost, and need for rehabilitation. All procedures were performed using identical preoperative, intraoperative, and postoperative protocols. Postoperative confusion was approximately four times greater in the simultaneous bilateral total knee arthroplasties group (29% versus 7%), which was thought to represent an increased incidence of fat embolism. Cardiopulmonary complications were approximately three times greater after simultaneous bilateral total knee arthroplasties (14% versus 5%), and most commonly involved arrhythmias. The increased stress on the cardiopulmonary system with simultaneous bilateral total knee arthroplasties may make this procedure contraindicated in certain patients with preexisting disease. There was an approximately 17 times greater need for banked blood in the simultaneous bilateral total knee arthroplasties group (17% versus 1%), which is alarming given the persistent concerns of transfusion related disease transmission. Although the length of hospitalization was similar (6.4 days simultaneous bilateral total knee arthroplasties versus 6 days unilateral total knee arthroplasty), 89% of the patients in the simultaneous bilateral total knee arthroplasties group required a rehabilitation stay versus 45% of the patients in the unilateral total knee arthroplasty group. Total hospital charges averaged

Treatment Versus Non‐Treatment of Hip Dislocations in Ambulatory Patients with Myelomeningocele

53,168 for simultaneous bilateral total knee arthroplasties versus

Wavelength selection in laser arthroscopy

32,598 for unilateral total knee arthroplasty. Total rehabilitation charges were similar. The relative cost savings implicit by doing simultaneous bilateral total knee arthroplasties seem to be at least partially offset by the approximately two times greater need for rehabilitation in this group. The true safety, efficacy, relative risk, and total cost analysis of simultaneous bilateral total knee arthroplasties demands further critical evaluation.

Carbon dioxide laser removal of polymethylmethacrylate.

Traiternent ou non traiternent de la luxation de la hanche chez les spina‐bifida pouvant se déplacer

Percutaneous lumbar discectomy using Ho:YAG laser

Electrosurgical devices and various lasers are used to cut human meniscal tissue, and the amount of thermal damage caused by each method is measured and compared.

Technique of CO2 laser arthroscopic surgery

Polymethylmethacrylate remains an excellent method of securing orthopaedic implants. However, revision surgery may be necessary when loosening of the prosthesis has occurred with symptomatology. Removal of polymethylmethacrylate during revision surgery can be difficult. Care must be taken to avoid damage to the remaining bone and surrounding soft tissue. This study was undertaken to characterize the efficacy of the carbon dioxide (CO2) laser for cement removal in vitro and in vivo. The CO2 laser did not damage adjacent bone or soft tissue via lateral heat transfer in vitro and in vivo. The maximum bone cortex temperature during CO2 laser removal was 56 degrees C. This was lower than the 60 degrees C temperature encountered during initial cement insertion and curing. The CO2 laser preferentially penetrates polymethylmethacrylate with absorption versus apparent relative reflection with bone. The products of vaporization from CO2 laser removal of polymethylmethacrylate were removed safely (to < 12.2 ppm) with a smoke evacuator without risk to the patient or operating room personnel. Removal of polymethylmethacrylate by CO2 laser was performed in 117 patients undergoing revision operations, including 78 total hip revisions, 33 total knee revisions, 3 total elbow revisions, and 3 spine revisions. No perforation or fracture of bone occurred with the use of the laser. There was no statistical difference in surgical time, blood loss, infection rate, or hospital stay when the CO2 laser was used. There were no cases of osteonecrosis or obvious soft tissue necrosis caused by the laser. The infection rate was 3.4% (4/117) when the laser was used for cement removal.

Stimulatory effects of Nd:YAG lasers on canine articular cartilage

The Ho:YAG laser is used to perform percutaneous lumbar discectomy in swine to evaluate the procedure as a potential clinical tool.

Thermal Effects of Infrared Laser Systems

The CO2 laser was selected for arthroscopic surgery due to its availability in the hospital high power output and excellent absorption by unpigmented tissues. During the course of this study 4 generations of laser instruments were tested. These include the focused beam delivered via a handpiece the (3 mm O.D.) macrowaveguide the (1.5 mm Q.D.) microwaveguide and the flexible waveguide. The latter two devices complement each other in that the microwaveguide will tolerate and retain up to a 30 degree(s) curve. The flexible waveguide will clear narrow joint tolerances without creating lesions in the articular surface. CO2 laser arthroscopic tissue ablation must be done under gaseous joint distention but this presents no undue difficulties. At the completion of the procedure saline irrigation must be done for char removal.

CO2 partial matricectomy in the treatment of ingrown toenails

PURPOSE: To determine the effects of Nd:YAG laser energy on the healing of full- and partial-thickness articular cartilage defects in canines

Endoscopic removal of PMMA in hip revision surgery with a CO2 laser

Laser use in arthroscopy is becoming increasingly common, and the effectiveness and efficiency of numerous systems have been well documented (Sherk et al., 1992). Application of these lasers to intraarticular tissue causes tissue cutting and ablation but can also cause surrounding tissue damage or necrosis. The amount of damage sustained by the tissue is important because the tissue may be permanently damaged and unable to regenerate. This depth of tissue damage depends on the type and specific wavelength of each laser system utilized. We have evaluated various lasers for their effects on meniscal tissue by morphometric and histologic analysis. These lasers have been or are currently being used for arthroscopic knee surgery, and they vary widely in respect to their wavelengths.