Many anatomical variations exist in and around the carpal tunnel. However, symptomatic anomalies causing carpal tunnel syndrome is rare. Additionally, carpal tunnel surgery is considered a simple operation commonly done by junior surgeons who are usually unaware of variations resulting in unfavorable surgical outcomes. We highlight a case of lumbrical muscle variation causing carpal tunnel syndrome. A 73-year-old male presented with numbness and pain of both hands associated with abnormal fullness over both wrists and distal forearms. Initially the right hand was numb and subsequently a year later, the left hand became numb. Physical examination was positive for Durkan, Phalen and Tinel signs at the carpal tunnel. Magnetic Resonance Imaging (MRI) showed abnormal muscle tissues in the carpal tunnel. During the carpal tunnel release and exploratory surgery, we noted an abnormally proximal origin of the lumbrical muscles in the forearm rather than the typical palmar origin. He also had lumbrical muscle hypertrophy in the left side. These two factors resulted in overcrowding within the carpal tunnel. Post-operatively the patient recovered well with pain relief and gradual improvement of his numbness. Variations in the anatomy of the lumbrical muscles is not uncommon and may result in carpal tunnel syndrome. Hence, carpal tunnel release surgeries may not be as straight forward as expected and surgeons should be aware of this possibility.
BACKGROUND: Ustekinumab is a fully human monoclonal antibody approved for the treatment of chronic moderate-to-severe plaque psoriasis in adults. However, factors including efficacy, tolerability, ease of use, and cost burden may affect ustekinumab utilization. Noncompliance may, in turn, affect treatment response.
OBJECTIVE: To evaluate ustekinumab utilization in the real-world setting in Asia-Pacific countries.
METHODS: In this phase 4 observational study conducted in Indonesia, Malaysia, Singapore, Korea, and Taiwan, adults with plaque psoriasis receiving ustekinumab were followed for up to 52 weeks. Study endpoints were the proportion of all patients using ustekinumab according to label-recommended intervals and the proportion of Korean patients who achieved a psoriasis area severity index 75 response at week 16. Safety was assessed by monitoring adverse events.
RESULTS: Overall, 169 patients received ustekinumab (Korea, n=102; other countries, n=67). Just over half (56.2%) of patients used ustekinumab with the label-recommended interval from baseline to week 40; the proportion was higher in Korea (73.5%) than in other countries (29.9%), probably because ustekinumab was provided without charge for Korean patients up to week 40. Noncompliance increased after week 40 in Korea and from week 28 in other Asia-Pacific countries, with cost cited as the most common reason. At week 16, 56.9% of Korean patients achieved a Psoriasis Area Severity Index 75 response. Safety results were in line with those seen in previous studies.
CONCLUSION: More than half of all patients in Asia-Pacific countries used ustekinumab as per the label-recommended dose interval, but reimbursement variations between countries may have confounded overall results.
KEYWORDS: Asia-Pacific; Compliance; Plaque psoriasis; Reimbursement; Ustekinumab