Treatment impact varied greatly for carpal tunnel syndrome (CTS) patients according to a multiyear review of research studies by Bland. Significant subjective improvement occurred among:
· 75% who underwent surgery
· 70% who were treated with local steroid injection (but with 50% experiencing a relapse of symptoms within one year)
· 30% who had wrist splinting
· 20% who received no treatment
There was a large range in success rates reported among surgical treatment studies: 27% to 100%. Also, lower surgical success rates have been reported in more recent years. Better outcomes, the author suggests, can occur with improved patient selection, greater use of local steroid injection, and surgical procedures performed only by highly skilled practitioners.
Study Design
A monthly Medline search was conducted from 2000 to 2006 to identify published research related to carpal tunnel syndrome. From the relevant articles, the reference lists were screened to expand the pool of inclusion studies.
The outcome of interest was patient reported symptom changes. Although different studies used different reporting scales (i.e., poor/fair/good, worse/no change/slightly better/much better/cured), success was defined as significant improvement. Articles whose outcome measure was an objective evaluation (i.e., nerve conduction study), a mean change of a patient group, or a difficult to assess finding were excluded.
These criteria produced a collection of 209 papers involving 32,936 operations. The studies were characterized by many research approaches such as case studies, controlled trials, and examinations of specific populations.
Other Findings
Surgical treatment provided slight improvement/no change for 17% of the patients while 8% described a worsening of their condition. Local steroid injection provided slight improvement/no change for 30% of the patients while less than 0.1% described a worsening of their condition. Wrist splinting provided slight improvement/no change for 70% of the patients while less than 0% described a worsening of their condition. When no treatment was applied, slight improvement/no change was seen by 40% of the patients while 40% reported a worsening of symptoms.
A poorer treatment outcome was associated with:
· An advanced clinical condition – objective neurological signs, constant subjective symptoms, grade 5/6 on nerve conduction study, poor activities of daily living score
· Unusual clinical features – atypical hand diagram, normal nerve conduction study, involvement of the 5th digit
· Concurrent clinical disorders – diabetes, arthritis
· Increased age
· Longer symptom duration
· Smoking
· Alcohol use
· Heavy manual occupation
· Workers’ compensation relatedness
Nonsteroidal anti-inflammatory drugs and diuretics were insufficiently tested to draw conclusions on effectiveness.
Local steroid injection had less complications/risks than surgery but also had less therapeutic impact. The need for repeat injections was common and performed by some practitioners over long durations (median number of injections – 12; average duration of benefit – 4.5 months). This approach was criticized by some practitioners as masking symptoms while nerve degeneration continued.
Reoccurrence of carpal tunnel syndrome symptoms (which usually means primary failure of surgery as opposed to true reoccurrence) was commonly associated with incomplete divide of the transverse carpal ligament (found in 91 of 185 reoperations). True reoccurrence of carpal tunnel syndrome does happen but at an unknown rate.
Article Title: Treatment of Carpal Tunnel Syndrome
Publication: Muscle Nerve 36: 167-171, 2007
Author: J D P Bland
This article originally appeared in The Ergonomics Report™ on 2007-08-28.