Functional electrostimulation therapy for vastus medialis decreases the varus thrust during gait.

[Purpose] This study aimed to investigate whether modification of vastus medialis activity can delay the varus thrust. [Participants and Methods] Ten participants (Kellgren-Laurence grades I: n=2, II: n=6, and III: n=2) diagnosed with knee osteoarthritis were enrolled. The intervention involved free walking on a 10-m walkway at any speed after donning a functional electrical stimulation set to contract the vastus medialis before heel contact. Using a Vicon Nexus ground reaction force meter and a wireless electromyograph DELSYS, varus thrust, maximal knee extension angle, maximal knee adduction moment, and vastus medialis onset time were assessed both before and after intervention. [Results] A significant difference in varus thrust was detected from before to after the intervention (2.7 ± 1.1° vs. 2.2 ± 1.3°). Both the vastus medialis activation time (-0.06 ± 0.09 vs. -0.21 ± 0.1) and the knee-joint extension angle (8.7 ± 5.1° vs. 5.5 ± 5.9°) decreased following intervention, whereas the knee adduction moment significantly increased (0.50 ± 0.20° vs 0.56 ± 0.18°). [Conclusion] Wearing the functional electrical stimulation set caused the vastus medialis to act earlier in response to heel strike, thereby improving the knee-joint extension angle and suppressing varus thrust.

Transforaminal percutaneous endoscopic discectomy for lumbar disc herniation in athletes under the local anesthesia.

BACKGROUND: Percutaneous endoscopic discectomy (PED) has been reported to be less invasive and effective procedure for lumbar disc herniation (LDH). Damage to the back muscle is considered minimal, which is particularly important for athletes. However, the results of PED for LDH in athletes have not been reported well. The purpose of this study was to evaluate the clinical outcomes of PED for LDH in athletes. METHODS: We retrospectively analyzed 21 athlete patients with LDH who had undergone PED. All patients received athletic rehabilitation immediately after surgery. The clinical outcomes were evaluated from the visual analogue scale (VAS) for leg pain and low back pain (LBP), the Oswestry Disability Index (ODI), complications and periods of return to sport. RESULTS: There were 18 men and 3 women, and the mean age at the time of surgery was 22.9 years (range: 15-43 years). The mean VAS scores for leg pain before and after surgery were 64.3 ± 2.7 mm and 12.4 ± 1.4 mm, respectively. The mean VAS scores for LBP before and after surgery were 62.1 ± 2.2 mm and 10.5 ± 1.1 mm, respectively. The mean ODI scores before and after surgery were 31.3 ± 14.0% and 14.6 ± 7.1%, respectively. The VAS for leg pain, as well as the LBP and ODI, significantly improved after surgery. There were no complications related to the surgery. Ninety-five percent (20/21) returned to play sports at the same performance level as before the procedure by an average of 9.2 weeks after PED. CONCLUSIONS: PED is a minimally invasive and effective procedure for patients with LDH, especially in athletes. Not only the patients' leg pain but also their discogenic LBP improved. PED has the benefits of preservation of normal posterior structures and a faster return to sports.

Magnetic force-assisted meniscal resection under arthroscopy.

Arthroscopic meniscectomy has become a standard procedure for a complete discoid meniscus or for displacement of a meniscal bucket handle tear, although it is not always easy due to poor visualization of the cutting portion. The purpose of this study is to examine whether meniscal resection can be easily carried out in a swine model using the magnetic force-assisted procedure, whereby a metal clip is attached to the meniscal flap and moved by an external magnetic force. Four fresh-frozen porcine lower extremities were used (age range: about 6 months). After opening the knee joint, a flap tear in the medial and lateral menisci was created. Then a metal clip was attached to the edge of the tear. With 20 cm distance between the knee and the disk of the external magnetic device, the flap was observed under arthroscopy. At the highest magnitude of 0.6 T, the direction of the magnetic field was changed. As the direction of the magnetic field was changed to move laterally, medially, up, and down, so the edge of the meniscal flap was observed to move in corresponding directions. Thanks to now having a clear view of the cutting portion, it was evident that meniscal resection could be easily carried out. Although we need to develop special instruments such as Titanium scissors and forceps and an external magnet system for surgery, the current study may be the first step towards a new era in the field of magnet-assisted arthroscopy.

Hyperbaric oxygen as an adjuvant for athletes.

There has recently been a resurgence in interest in hyperbaric oxygen (HBO) treatment in sports therapy, especially in Japan. Oxygen naturally plays a crucial role in recovery from injury and physiological fatigue. By performing HBO treatment, more oxygen is dissolved in the plasma of the pulmonary vein via the alveolar, increasing the oxygen reaching the peripheral tissues. HBO treatment is therefore expected to improve recovery from injury and fatigue. HBO treatment has been reported to reduce post-injury swelling in animals, and in humans; swelling was also mitigated, but to a lesser extent. Positive results have also been reported regarding tissue remodelling after injury, with injuries involving bones, muscles and ligaments showing improved recovery. Furthermore, HBO treatment has effectively increased recovery from fatigue. This was clearly seen at the Nagano Winter Olympics, where sports players experiencing fatigue were successfully treated, enabling the players to continue performing in the games. Despite its potential, HBO treatment does have its risks. Increasing oxygen levels in tissues poses a risk to DNA through oxidative damage, which can lead to pathological changes in the CNS and the lungs. Regarding the operating of HBO systems, safer administration should be advised. Further research into HBO treatment is required if this therapy is to become more widespread. It should become possible to tailor treatment to an individual's condition in order to use HBO treatment efficiently.