Management of carpal tunnel syndrome (CTS) is reasonably straightforward at the end of the disease spectrum: patients with minimal symptoms and only rare interference with activities of daily living need no treatment, and surgery should be strongly considered when symptoms persist or rapidly worsen despite a reasonable course of nonsurgical care or if muscle atrophy is present. There is no universally agreed-upon treatment paradigm for patients with mild to moderate CTS. People may have symptoms which wax and wane over decades: they may delay seeking professional evaluation and treatment, they may present for care at different stages of their disease, and they may be treated with conservative measures with intervening asymptomatic periods [1].

Care may be provided by a primary care physician , a neurologist, a physical medicine specialist, an occupational or physical therapist, or a surgeon. If the disease is felt to be work related, patients may be referred to an occupational medicine physician. Patients can easily be seen by physicians in three to four different fields for management of this very common disease. Despite the high prevalence of CTS, practitioners in various specialties spend little time interacting with one another to discuss the scientific literature and compare philosophies of care. If there is lack of multidisciplinary consensus on key elements of care, patients may receive information regarding causation, correlation, and treatment that can be inadvertently conflicting. Physicians have inherent biases about treatment: surgeons see the benefit of relatively rapid treatment response and lasting effect, but nonsurgeons may view surgery with a less benevolent eye. As one author stated, patients “can always submit to surgical therapy if necessary” (italics mine) [2].

When considering if and when to intervene, it is ideal to understand the natural history of a disease. Padua et al. [3] followed 196 patients with mild to moderate idiopathic carpal tunnel syndrome for up to 15 months and found spontaneous improvement in the symptom severity score (SSS ) element of the Boston Carpal Tunnel Questionnaire (BCTQ ) in 34% of patients, lack of progression of symptoms in 45%, and worsening in 21%. Similar patterns were seen in the functional status score (FSS ) (23% improved, 61% were stationary, and 16% worsened), pain (26%, 62%, and 12%, respectively), and electrodiagnostic tests (27%, 57%, and 16%, respectively). They identified several factors predicting disease worsening: bilateral symptoms, advancing age, and a positive Phalen test. Despite issues related to poor sensitivity and specificity, having a positive Phalen test at the initial assessment decreased the odds of spontaneous symptomatic resolution by 60%. A similar 24-month study was performed by Ortiz-Corredor et al. [4]. Of 189 people initially evaluated in their clinic, 57 (30%) had had a treatment intervention within 2 years (splint, injection, or surgery). Of the remaining 132 patients, they found clinical improvement in 48%, lack of progression in 29%, and deterioration in 23%. Electrodiagnostic studies showed improvement in 25%, stability in 67%, and deterioration in 8%. These outcomes support a minimalist approach in the initial management of the majority of patients with carpal tunnel syndrome.

Successful treatment of carpal tunnel syndrome, whether nonoperative or operative, should improve symptoms and limit nerve degeneration by decreasing pressure in the carpal tunnel, thereby improving vascular supply of the nerve and gliding of tendon and nerve relative to one another [5]. Given that anywhere from 23 to 48% of patients with mild to moderate CTS may spontaneously improve, studies looking at treatment efficacy should be powered to take this into account. Numerous nonoperative options for symptom relief are available; this chapter will review the literature regarding those options.

Outcome assessment tools have increasingly become patient centered [6]. Rather than solely focusing on clinicians’ views of what constitutes treatment success or failure, current philosophy of care focuses more on the patient’s experience. Though many scales have been used primarily for research purposes, incorporation of outcome measures into clinical practice is feasible [7]. Documentation of treatment efficacy will likely increasingly be required by healthcare systems and payers. For CTS, the Boston Carpal Tunnel Questionnaire scales (symptoms severity scale, SSS , and functional status scale, FSS ) are more sensitive and specific than more generic functional scales such as the SF36 [8, 9]. Other scales validated for use with CTS are the Michigan Hand Outcomes Questionnaire and the short form of the Disabilities of the Arm, Shoulder, and Hand (QuickDASH) [9]. The majority of recent CTS studies have used the BCTQ to evaluate treatment effects and a ten-point visual analog scale (VAS) to assess pain.

Physical exam assessments may include pinch and grip strength, Semmes-Weinstein monofilaments for light touch, moving and static two-point discrimination, manipulation of objects (Jebsen Hand Function Test), and electrodiagnostic studies [5]. Electrodiagnostic tests don’t always correlate with patient’s complaints [10], and cost and inconvenience make them less likely to be obtained for routine post-treatment evaluations. The most recent clinical practice guideline of the American Academy of Orthopaedic Surgery for carpal tunnel syndrome was less prescriptive regarding the necessity of obtaining electrodiagnostic tests in suspected cases of carpal tunnel syndrome [11], and recent surveys of upper extremity surgeons have found that it is becoming more acceptable to substitute a physical exam for electrodiagnostic exams [12, 13].

The majority of the studies discussed in this chapter focused on management of mild to moderate idiopathic carpal tunnel syndrome. Inclusion criteria were adult patients with symptoms of median nerve dysfunction in the hand for at least 1–2 months and positive electrodiagnostic tests showing mild to moderate changes. Electrodiagnostic severity of CTS was generally defined per criteria described in Padua [3]. Mild CTS is characterized by abnormal sensory latency, moderate CTS has abnormal motor latency with or without abnormal sensory latency, and severe CTS has absent sensory latency with concomitant muscle atrophy. Unless otherwise noted, exclusion criteria included patients with severe CTS; metabolic derangements associated with an increased risk for carpal tunnel syndrome (diabetes mellitus, hypothyroidism, pregnancy, obesity, gout, fibromyalgia, rheumatoid arthritis, and osteoarthritis); inability to take a drug being tested; prior treatment(s) for carpal tunnel syndrome; history of upper extremity trauma; polyneuropathy; cervical radiculopathy; bleeding dyscrasia; cardiac, renal, or hepatic disease; and the inability to give consent to participate in research. Study weaknesses included lack of use of a validated outcome measure in older studies, small sample sizes, and short follow-up periods. Efforts were made to include studies of moderate- to high-level evidence. When interpreting questionnaire outcomes, it is important to keep in mind the principle of the minimal clinically important difference (MCID ) as differences may be statistically significant rather than clinically important [14, 15]. For the SSS , Özyürekoğlu et al. [14] found that a decline of ≥1.04 points may be clinically important.