O. Sahap Atik

Reliability of the safe area for the superior gluteal nerve.

The authors investigated the reliability of the safe area, which previously was defined to prevent injury to the superior gluteal nerve during the lateral approach to the hip, and its relation to body height. The distance between the point of entry of the superior gluteal nerve into the gluteus medius muscle and the greater trochanter, in the regions which were defined as the anterior and posterior halves of the muscle, were measured in 23 cadaveric hips. There was a significant correlation between the height of the cadavers and the distance in the anterior and posterior regions. In all of the anterior regions and 78% of the posterior regions of the hips, the superior gluteal nerve as found to be in the safe area. The current study showed that the average distance between the innervation point of the gluteus medius muscle and the greater trochanter might change as a function of body height. The risk of damage to the superior gluteal nerve may be higher if the direct lateral approach to the hip is used. These data show that it is possible that the safe area is not always safe.

Histological and magnetic resonance imaging alterations after irradiation of meniscus using Holmium:YAG laser.

OBJECTIVE The authors performed an experimental and a prospective clinical study to evaluate the histological and magnetic resonance imaging (MRI) alterations after irradiation of meniscus using holmium:YAG (Ho:YAG) laser VersaPulse Select 60 watts and InfraTome Delivery Systems 30 degrees Handpiece (spot size at fiber tip 0.4 mm; Coherent Medical, Palo Alto, CA). BACKGROUND DATA Recently, some authors reported a few cases with articular cartilage damage or paraarticular osteonecrosis following arthroscopic knee surgery in which the laser was used to assist in the treatment of meniscal pathology. METHODS Meniscus specimens in saline immersion were exposed to Ho:YAG laser irradiation. The laser wavelength was 2.1 microm and pulse duration was 250 microsec. Power settings were 1-1.5 joules per pulse and 10-15 Hz. Total laser energy used in these procedures was 2, 3.5, and 6 K joules. Eight patients with meniscal problems underwent arthroscopic partial meniscectomy using Ho:YAG laser. Total laser energy used for these surgeries was 1.5-2.5 K joules. MRI was performed preoperatively and at 6 months postoperatively. RESULTS At higher energy levels (more than 3 K joules), separation of the gap between the collagen fibers, and a three-dimensional dispersion in the striation were observed on electron microscopic evaluation of meniscus specimens. No patient had abnormal signals in MRI (a sign of articular cartilage damage or osteonecrosis) following arthroscopic laser surgery. CONCLUSION When higher energy level is required, conventional instruments should be preferred in the treatment of meniscal lesions. Laser should be reserved for the posteriorly located and smaller meniscal lesions.

Histological Alterations after Irradiation of Cartilage Using Ho:YAG Laser

OBJECTIVE The authors carried out an experimental study to evaluate the histological alterations after irradiation of cartilage using Holmium:YAG (Ho:YAG) laser VersaPulse Select 60 watts and Infra Tome Delivery Systems 30 degrees Handpiece (spot size at fiber tip 0.4 mm; Coherent Medical, Palo Alto, CA). BACKGROUND DATA Recently, some authors reported cases with articular cartilage damage following arthroscopic laser surgery in the knee joint for the treatment of articular cartilage or meniscal pathology. MATERIALS AND METHODS The cartilage specimens immersed in saline were exposed to Ho:YAG laser irradiation. The laser wavelength was 2.1 microm, and pulse duration was 250 microsec. Power settings were 0.2-1 joules per pulse and 10-15 Hz. Total laser energy used in these procedures was 1.5 K joules. During the procedures, the handpiece was used at an angle of 30 degrees and at a distance of 1 mm. RESULTS Electron microscopic evaluation demonstrated that the ultrastructure of the cartilage is preserved in both experiment and control groups. CONCLUSION When Ho:YAG laser is used in optimal dosage (optimal joule and Hertz) with optimal technique (keeping the handpiece at an appropriate angle and distance) and avoiding overtreatment, it does not cause cartilage damage.

Surgical repair of cartilage defects of the patella.

The structure and biomechanical forces on the patellar joint challenges researchers to define an ideal method for resurfacing the patellar cartilage. The articular surface of the patella presents variability between individuals, and has various minor articulations that bear partial or total compressive, shear, and combined forces during movement. Surgical techniques for the repair of patellar cartilage defects have evolved from cumulative advances in basic science and technology. Such surgeries include the techniques that promote either fibrocartilage formation or hyalinelike cartilage formation. Techniques promoting the formation of fibrocartilage yield short-term solutions because fibrocartilage lacks the durability and the mechanical properties of articular hyaline cartilage. Currently, there is no ideal method for the repair of patellar cartilage defects; all methods are considered experimental. Additional controlled and randomized clinical studies with large series of patients and long-term followup are required.

Osteoporosis and Sports

Osteoporosis most commonly affects postmenopausal women. The strategies for preventing osteoporotic fractures are maximizing peak bone mass, counteracting age- and menopause-related bone loss.