Wu, Kitty Y.

Abstract Background Ultrasound (US)‐guided hydrodissection is a minimally invasive treatment for cubital tunnel syndrome (CuTS) with promising early results. However, data on patient‐perceived outcomes, durability of relief, and impact on surgical need remain limited. Objective To assess the effectiveness of US‐guided cubital tunnel hydrodissection in improving CuTS symptoms via patient‐centered outcomes. Design Retrospective chart review with cross‐sectional telephone follow‐up. Setting Quaternary medical center multidisciplinary outpatient hand clinic. Participants Seventeen patients (19 arms) with clinical CuTS who received US‐guided hydrodissection from one physician. Interventions Patients were contacted by telephone for cross‐sectional outcome assessment. Main Outcome Measures Patient‐reported improvements in weakness, paresthesias, and/or pain, percent pain relief, symptom improvement duration, adverse events, and Patient Global Impression of Change (PGIC) scores. Results At mean 7 ± 5 month follow‐up, improvement in weakness, paresthesia, and pain was reported in 12 (63%) extremities (95% confidence interval [CI] 41%–85%; p < .001) . Pain relief ≥50% occurred in 12 (63%) and ≥75% in 8 (42%) extremities, with mean duration 4 months. PGIC scores showed 14 (74%; 95% CI 54%–94%; p < .001) at least “minimally improved” and 8 (42%) (95% CI 20%–64%; p < .001) “much improved.” No adverse events occurred. Two patients without improvement underwent surgical decompression with anterior transposition at 1 and 3 months after hydrodissection, achieving 90%–100% pain relief and “much or very much improved” PGIC scores. Of 19 extremities, 7 (37%) were McGowan Grade I and 12 (63%) Grade II; none were Grade III. Grade II extremities showed significantly greater overall symptom relief ( p = .004) and pain relief ≥50% ( p = .004). PGIC scores did not differ significantly between grades (both p > .062). Conclusion US‐guided cubital tunnel hydrodissection was associated with meaningful symptom improvement and no adverse events. Limitations include small sample size, no control group, single operator, and potentially time‐limited relief. The procedure appears safe and a potential nonoperative treatment option.

ABSTRACT Introduction/Aims Ultrasound (US) guidance may be essential for accurate electromyography (EMG) needle placement in less‐commonly evaluated muscles, such as the extensor carpi radialis longus (ECRL) and brevis (ECRB), and particularly for identifying suitable donor muscles prior to tendon transfers to restore upper extremity function. Our primary aim was to compare the accuracy of trainee palpation‐guided versus first‐attempt US‐guided needle placement. Our secondary aim was to describe the locations of inaccurate needle placement. Methods Seven subjects each performed four needle placements (ECRL and ECRB, both palpation‐guided and US‐guided), totaling 28 placements into a cadaveric specimen. US‐guided needle placement was performed with one attempt after one live demonstration. Results No palpation‐guided ECRL attempts were accurate while only two of the palpation‐guided ECRB attempts were accurate. First‐attempt US‐guided needle placement was significantly more accurate overall (64.3% vs. 14.2%, p = 0.020), and specifically for ECRL (71.4% vs. 0%, p = 0.025). Combining palpation‐guided ECRL and ECRB attempts, the needle was inadvertently placed in the extensor digitorum communis (50%), extensor carpi ulnaris (16.7%), and brachioradialis (16.7%). Both US‐guided ECRL‐intended errors involved placing the needle into the adjacent ECRB. Discussion This study suggests that EMG needle placement into ECRL and ECRB by trainees may be more accurate with US guidance. Accurate preoperative individual needle assessments of both wrist extensors are essential for patients with tetraplegia considering reconstructive surgery to restore functional grasp and should be performed with US guidance.

ABSTRACT Introduction/Aims Patients with cervical spinal cord injury (SCI) prioritize recovery of upper extremity function. Upper extremity reconstruction can restore function in carefully selected individuals. Infralesional cord damage, observed below the neurological level of injury (NLI), may affect postoperative outcomes. We characterized the extent of infralesional lower motor neuron (LMN) injury in patients with traumatic cervical SCI. Methods Each patient underwent electromyography (EMG) of potential donor and recipient muscles based on preoperative clinical evaluation and specific candidacy for nerve and/or tendon transfers. The presence of infralesional pathologic insertional activity (IA), reduced motor unit potential (MUP) recruitment and/or neurogenic MUPs was assessed. The caudal‐most segment with infralesional LMN injury was determined. Inclusion criteria were patients with (1) traumatic cervical SCI; (2) injury ≥ 3 months duration; (3) preoperative planning EMG for nerve and/or tendon transfers. Results Forty‐eight upper extremity EMGs in 25 patients (68% male; mean age 39.5 years at injury) with traumatic cervical SCI were included. The NLI was at C7 or above in each patient, and 64% of SCIs were motor complete. Infralesional EMG abnormalities (median time from injury to EMG 466 days) were found a median of 3.0 (IQR 3.0–4.0) segments below the NLI. Three patients with an NLI as rostral as C1–C2 exhibited LMN injury seven segments below the NLI. Discussion In persons with traumatic cervical SCI, evidence of LMN injury may be observed several segments below the NLI. Defining the true extent of LMN involvement directly informs timing and selection of reconstructive procedures to maximize functional recovery.