Alterations in forearm muscle activation patterns after scapholunate interosseous ligament injury: A dynamic electromyography study

Electromyography Parameters to Discriminate Hand Osteoarthritis and Infer Their Functional Impact

Surface-electromyography (sEMG) allows investigators to detect differences in muscle activation due to hand pathologies. However, its use as a functional indicator and the challenges related to the required normalization have not been fully addressed. This study aimed to use forearm muscle sEMG signals to distinguish between healthy individuals and patients with hand osteoarthritis (HOA). sEMG data were collected from seven sensors on the forearms of twenty-one healthy women and twenty women with HOA during the Sollerman test. Amplitude-based parameters (median and range) were normalized using three methods: maximum signals during Sollerman tasks (MAX), during maximum voluntary contraction tasks (MVC), and during maximum effort grasping (GRASP). Waveform parameters (new-zero-crossing and enhanced-wavelength) were also considered. MVC and GRASP resulted in higher values in patients. Discriminant analysis showed the worst success rates in predicting HOA for amplitude-based parameters, requiring extra tasks for normalization (MVC or GRASP), while when using both amplitude (MAX) and waveform parameters and only Sollerman tasks, the success rate reached 90.2% Results show the importance of normalization methods, highlight the potential of waveform parameters as reliable pathology indicators, and suggest sEMG as a diagnostic tool. Additionally, the comparison of sEMG parameters allows the functional impact of suffering from HOA to be inferred.

Can a structured home-based rehabilitation program reduce dorsal central wrist pain?

OBJECTIVES

Dorsal central wrist pain, often a consequence of peri-scapholunate ligament injury, can result in a decline in functional performance. There is a scarcity of clinical data evaluating the effectiveness of conservative management on peri-scapholunate ligament injury. Conservative management includes education, immobilization with orthotic devices, scapholunate-stabilizing muscle strengthening, and proprioception training. The identification of the ligamento-muscular reflex and scapholunate-stabilizing muscles formed the rationale for a rehabilitation training program. We have devised an innovative standardized 16-week treatment program for patients with dorsal central wrist pain associated with acute peri-SL ligament injury. We hypothesized that the program can effectively reduce dorsal wrist pain and improve functional performance.

MATERIALS AND METHODS

Recruited subjects underwent the 16-week home-based program, which included immobilization and rehabilitation exercises, to improve their wrist stability. Follow-up was arranged every 4 weeks for progress monitoring. The Short-Form 12 item questionnaire version 2, power grip, pinch grip, wrist range of motion, total performance score and total pain score when performing activities of daily living were used to evaluate the effectiveness of the program. An exercise adherence questionnaire was used to evaluate adherence to the home rehabilitation program.

RESULTS

Twenty-three subjects (26 wrists) completed the program. Pain on visual analog scale improved by 5.1 cm and total pain score improved from 14.4/20 to 19.5/20. Total performance score reached 39/40, which indicated near-normal wrist function. Power grip and pinch grip increased by 22.3% and 17.8%, respectively. The physical component scale of the Short-Form 12 item questionnaire showed significant improvement, while the mental component scale did not. Overall adherence was fair.

DISCUSSION

Conservative management, including immobilization and rehabilitation training, can provide significant clinical improvement in patients with dorsal central wrist pain associated with acute peri-scapholunate ligament injury.

CONCLUSION

Standardized wrist rehabilitation can be taken as a reference treatment modality. It is an evidence-based non-invasive treatment option for clinicians and therapists.

Case-based report of graded motor imagery experience in traumatic brachial plexus injury: The art of moving without moving

BACKGROUND

We reported a 24-year-old woman who sustained multiple upper limb injuries after a traffic accident in March 2017. She sustained a C7-T1 brachial plexus injury and radial nerve injury on the left side diagnosed in November 2017. The patient underwent radial nerve reconstruction. The patient began her comprehensive therapy program in January 2018.

PURPOSE

To describe the use of graded motor imagery (GMI) and outcomes after traumatic brachial plexus palsy. We presented changes in electromyographic (EMG) activity of target muscles during task execution and functional status following 10-session GMI therapy.

STUDY DESIGN

Case report.

METHODS

The program included 4 sessions of motor imagery and 6 sessions of a combination of motor imagery and mirror therapy.

RESULTS

The patient successfully participated in the program with reported improvements in EMG activity, functional status, emotional well-being, and body awareness.

CONCLUSIONS

GMI therapy appears to have peripheral motor effects, including altered surface EMG activity and contributes to a favorable outcome in the functional level of the affected arm. An improved emotional state and awareness of the affected hand could have a positive effect on function. Future long-term randomized controlled trials are needed to investigate the cumulative peripheral effects of treatment of graded motor imagery and the effects of variables mediating its effects on functional performance in patients with nerve injury.

Bilateral Ulnar Deviation Supination Stress Test to Assess Dynamic Scapholunate Instability

PURPOSE

We describe a new radiologic test to assess the integrity of the scapholunate ligament in dynamic scapholunate dysfunction.

METHODS

A bilateral forearm-holding device was designed to perform a comparative radiographic assessment of the scapholunate joint gap during resisted isometric contraction of the extensor carpi ulnaris muscle with full supination of the forearm. The concept is based on the known scaphoid pronation effect of this muscle. Clinical data from 12 patients were collected retrospectively and used to analyze the patients' symptomatic and asymptomatic (contralateral) wrists with a newly developed test called the Bilateral Ulnar Deviation Supination (BUDS) test. A wrist arthroscopy was performed in all cases as a reference standard for the radiologic test.

RESULTS

The test was positive in 7 patients, with a mean scapholunate joint gap of 4.8 mm. The mean differences in the scapholunate joint gaps between both wrists were 2.6 mm in BUDS-positive patients and 0.2 mm in BUDS-negative patients. A Geissler stage III or IV scapholunate ligament rupture was confirmed in all BUDS-positive patients; by contrast, BUDS-negative patients exhibited either no lesion or a Geissler stage I injury.

CONCLUSIONS

The BUDS test is a new radiologic test based on proven biomechanical effects that is able to accurately assess dynamic scapholunate dysfunctions. The analysis carried out found a correlation between radiographic and arthroscopic findings. Further research is needed to confirm the validity and reliability of the test.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.