Pulos, Nicholas

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.

Patients with traumatic brachial plexus injuries (TBPI) undergo clinical examination and electromyography (EMG) to characterize injury severity and localization. However, precise localization with EMG alone can be difficult when multiple injury sites are possible. Brachial plexus ultrasound (BPUS) allows direct visualization of the brachial plexus, a needed adjunct to EMG to reveal multiple sites of injury in TBPI. We summarize three cases of EMG-confirmed upper trunk TBPI which were clarified using BPUS to additionally involve electrically hidden injuries to the extraforaminal C5 and C6 nerve roots. BPUS demonstrated extensive scarring and focal enlargement of the upper trunk in each patient (all cross-sectional area [CSA] ≥24 mm 2 ). However, all patients also had C5 and C6 extraforaminal nerve root enlargement (all CSA ≥9 mm 2 and 12 mm 2 , respectively), revealing further neural involvement proximal to the upper trunk into the EMG “gray zone”– postganglionic, extraforaminal cervical nerve root injury which is clinically and electrodiagnostically indistinguishable from the plexus but anatomically and radiographically distinguishable on BPUS. Some EMG-identified upper trunk TBPI may have more proximal involvement of the contributing extraforaminal C5-6 nerve roots, an area electrically indistinguishable from an upper trunk TBPI without the assistance of advanced imaging.