Biomedical subjects

Ji-Hye Hwang

Publications and source records attributed to Ji-Hye Hwang.

4 recordsLinked to original sources

PubMed2004

Excisional surgery for chronic advanced lymphedema.

PURPOSE: We conducted a retrospective study to evaluate the efficacy of excisional surgery to treat chronic advanced lymphedema. Excisional surgery was performed to reduce the extremity size, improve limb function, and decrease the frequency of lymphangitis and prevent sepsis. METHODS: Between August 1997 and December 2001, we performed excisional surgery on one or two affected legs in 20 patients with chronic lymphedema (total 24 legs). The lymphedema was graded as stage III in 5 extremities and as stage IV in 19 extremities. Five patients had primary lymphedema and 15 had secondary lymphedema. The mean duration of follow-up was 17.8 months. RESULTS: Excisional surgery resulted in clinical improvement in 18 extremities, all of which received regular physiotherapy after surgery. However, lymphedema progressed to the preoperative status in six extremities, four of which did not receive regular physiotherapy after surgery. CONCLUSIONS: Excisional surgical therapy can be effective for chronic advanced lymphedema, but appropriate postoperative physiotherapy is essential to ensure that the effects last.

Chronic Disease↗

PubMed2004

Reflexive muscle activation alterations in shoulders with anterior glenohumeral instability.

BACKGROUND: Patients with glenohumeral instability have proprioceptive deficits that are suggested to contribute to muscle activation alterations. HYPOTHESIS: Muscle activation alterations will be present in shoulders with anterior glenohumeral instability. STUDY DESIGN: Posttest-only control group design. METHODS: Eleven patients diagnosed with anterior glenohumeral instability were matched with 11 control subjects. Each subject received an external humeral rotation apprehension perturbation while reflexive muscle activation characteristics were measured with indwelling electromyography and surface electromyography. RESULTS: Patients with instability demonstrated suppressed pectoralis major and biceps brachii mean activation; increased peak activation of the subscapularis, supraspinatus, and infraspinatus; and a significantly slower biceps brachii reflex latency. Supraspinatus-subscapularis coactivation was significantly suppressed in the patients with instability as well. CONCLUSIONS AND CLINICAL RELEVANCE: In addition to the capsuloligamentous deficiency and proprioceptive deficits present in anterior glenohumeral instability, muscle activation alterations are also present. The suppressed rotator cuff coactivation, slower biceps brachii activation, and decreased pectoralis major and biceps brachii mean activation may contribute to the recurrent instability episodes seen in this patient group. Clinicians can implement therapeutic exercises that address the suppressed muscles in patients opting for conservative management or rehabilitation before and after capsulorraphy procedures.

Adult↗

PubMed2003

Shoulder muscle reflex latencies under various levels of muscle contraction.

Previous research in relaxed muscles shows that muscle reflex latencies are too slow to protect the shoulder. However, during athletic activity when injury occurs, some level of shoulder muscle contraction typically exists. The purpose of the current study was to assess shoulder muscle reflex latencies under various levels of muscle contraction. Seventeen healthy subjects participated. A perturbation consisting of an external rotation collision force to the anterior forearm in a position of apprehension under various levels of muscle contraction (0%, 20%, and 50% of a maximum voluntary muscle contraction) was applied. Muscle reflex latencies were measured as the time from perturbation application to onset of muscle activity. Electromyography measured activity onset of the rotator cuff muscles and the primary humeral movers. During 0%, the latissimus dorsi muscle reflex latency was significantly slower than most other muscles. No difference existed between muscles in the 20% and 50% conditions. For the rotator cuff muscles, the reflex latencies significantly quickened for 20% and 50% compared with the relaxed state (0%). Overall, introducing muscle contraction significantly quickened muscle reflex latencies. These results provide clinicians with a better understanding of the role that these reflexes play in joint stability in a position of injury vulnerability like a position of apprehension.

Adult↗

PubMedDate not supplied

Effect of peripheral afferent alteration of the lateral ankle ligaments on dynamic stability.

BACKGROUND: The sensorimotor influence of the lateral ankle ligaments in muscle activation is unclear. HYPOTHESIS: The lateral ankle ligaments have significant sensorimotor influence on muscle activation. STUDY DESIGN: Controlled laboratory study. METHODS: Muscle-firing characteristics in response to a high-speed inversion perturbation and during gait were assessed in 13 normal subjects. Solutions (1.5% lidocaine or a placebo of saline) were injected bilaterally into the anterior talofibular and calcaneofibular ligaments (1.5 ml per ligament) to alter peripheral afferent influence. Subjects were again tested with the same protocol. RESULTS: The protective response of the anterior tibialis and peroneal muscles during inversion perturbation and mean muscle activation amplitude decreased during running after both injections. After injection, no significant differences were seen for muscle reflex latencies, maximum amplitude, time to maximum amplitude during inversion perturbation, or mean amplitude during walking. CONCLUSION: The lateral ankle ligaments have a sensorimotor influence on muscle activation. CLINICAL RELEVANCE: Induced edema from the injected solutions may have altered the sensorimotor influence of the lateral ankle ligaments, thereby inhibiting the dynamic ankle stabilizers. This finding suggests that dynamic stability may be compromised because of swelling after joint injury.

Adult↗