Dicky T.C. Fung

The Combined Treatment Effects of Therapeutic Laser and Exercise on Tendon Repair

OBJECTIVE In this study we investigated the effects of different intensities of therapeutic laser energy and running exercise, and their combined effects on the repair of Achilles tendons in rats. MATERIALS AND METHODS Thirty-six mature Sprague-Dawley rats that received surgical hemi-transection of their right Achilles tendon were tested. Three laser dosages (4 J/cm2, 1 J/cm2 and 0 J/cm2) and three running periods (30 min, 15 min, and 0 min) resulting in nine different dosage and time groups were studied with four rats in each group. The treatments were given on alternate days starting on day 5 post-injury. On day 22, the tendons were tested for load-relaxation, stiffness, and ultimate strength. RESULTS There was a significant effect of laser energy on normalized load-relaxation, the rats receiving 4 J/cm2 had less load-relaxation than those receiving no laser treatment (p = 0.05). Results of stiffness testing revealed a significant effect, and rats that ran for 30 min had more stiffness than those that did not run (p = 0.015). For ultimate strength, due to a significant interaction (p = 0.05), the two factors were analyzed separately, and the results showed that for rats receiving no laser therapy, those that had run for 15 min and 30 min had more strength than those that did not run (p = 0.02 and 0.04, respectively). CONCLUSIONS Both laser therapy and running were found to hasten Achilles tendon repair In general, the rats that received higher dosages of laser energy (4 J/cm2) and ran for longer periods (30 min) performed better than those that received lower dosages of laser energy and ran for shorter periods.

Investigation of the collagen fibril distribution in the medial collateral ligament in a rat knee model

This study compared the collagen fibril diameter distribution among six anatomical sites of the rat medial collateral ligament (MCL). Ultrathin MCL sections from 4 male Sparague-Dawley rats were examined electron microscopically. With an automated quantitation method, 41,638 fibrils were measured and compared among the periphery and core regions of the femoral, middle, and tibial portions of the MCL. Results demonstrated significant difference ( p < .0033) in mean fibril diameter distribution among the six sites. The mass-averaged diameters of the core and peripheral fibrils were between 175.53 to 190.82 nm and 88.47 to 109.18 nm, respectively, with the peripheral fibrils more homogeneous in size. The fibrils occupied 36.7% to 57.1% of the cross-sectional area of the ligament. About 50% of the fibrils had an oblique factor of 0.8-1.0, implying that most fibrils were aligned longitudinally. This study has provided a detailed profile of the collagen fibril distributions in rat MCL.

Combined Treatment of Therapeutic Laser and Herbal Application Improves the Strength of Repairing Ligament

The present study investigated the effects of combined therapeutic laser and herbal medication protocols on injured medial collateral ligaments (MCLs) of rat knees. Fully 36 rats were evenly divided into 9 groups. Right MCLs of groups 1 to 6 and 8 were transected, while that of groups 7 and 9 remained intact. After surgery, group 1 was treated with 1 session of high-dosed laser; group 2 with 9 sessions of low-dosed laser; group 3 with an herbal plaster; groups 4 and 5 received combined treatments of groups 1 and ß and 2, and 3 respectively; groups 6 and 7 received only bandaging; groups 8 and 9 received placebo laser and no treatment, respectively. All MCLs were subjected to biomechanical testing at 3 weeks postsurgery. Results revealed significant differences among groups in ultimate tensile strength (UTS) and stiffness (p < 0.01). Combination of multiple low-dosed laser treatment with herbal treatment (group 5) resulted in higher UTS than either no treatment (groups 6 and 8), single high-dosed laser treatment (group 1), multiple low-dosed laser treatment (group 2), or herbal treatment (group 2) alone. We concluded that combined applications of laser and herb can enhance further biomechanical properties of repairing rat MCLs than separate applications at 3 weeks postinjury.

Effects of Herbal Application on the Ultrastructural Morphology of Repairing Medial Collateral Ligament in a Rat Model

The present study investigated the effects of an external herbal application on the ultrastructural morphology of repairing medial collateral ligament (MCL) in a rat model. Eight MCL-transected/herb-treated rats (group 1) were compared with 8 MCL-transected/placebo-treated controls (group 2) and 8 MCL-intact/placebo-treated rats (group 3). At 3 and 6 weeks posttransection, MCL specimens were examined under electron microscope. With analysis of 370,709 collagen fibrils, all herb-treated animals had significantly larger fibrils than the controls (p <. 001) at 6 weeks postinjury. The mean diameter of those peripheral collagen fibrils of group 1 was larger than the sham group (p <. 001). The mass-averaged diameters of group 1 (50.49 to 143.07 nm) and group 3 (59.69 to 188.88 nm) were larger than group 2 (50.59 to 121.94 nm). The area coverage by collagen fibrils ranged from 46.86 to 94.97% for group 1 and 43.70 to 68.08% for group 3 as compared with 40.01 to 50.77% for group 2. Mode obliquity was 0.56 to 0.84 among groups. We concluded that herbal remedy increases collagen fibril size of healing rat MCLs homogeneously at 6 weeks posttransection.

Combining therapeutic laser and herbal remedy for treating ligament injury: an ultrastructural morphological study.

OBJECTIVE We examined the ultrastructural morphology (number of collagen fibrils, mean and mass-averaged diameter) of isolated and combined treatments of a therapeutic laser and herbs for medial collateral ligament (MCL) injury in rats. MATERIALS AND METHODS Twenty-eight rats, divided into seven groups: laser (L), herb (H), laser + herb (LH), laser control (LC), herb control (HC), laser sham (LS) and herb sham (HS), were studied. Right MCL of groups L, H, LH, LC and HC were transected, while that of LS and HS remained intact. Group L received 9 treatment sessions of GaAlAs laser with a dosage of 3.5 Jcm(-2); group H received herbal plaster treatment; groups LH had combined treatments of laser and herb; group LC had placebo laser; group LS had no treatment; groups HC and HS received only bandage without herb. All MCLs were analyzed using transmission electron microscopy at 3 weeks. RESULTS Differences (p < 0.05) existed in mean fibril diameters among groups. Core mass-averaged diameters of groups L and H were larger than the control groups (LC and HC). Fibril diameter of group LH (combined treatment) was even larger and approaching that of the intact MCL. CONCLUSION Combined therapeutic laser and herbal treatment hastened collagen fibril maturation in MCL repair.