Secondary CTS
Although the majority of cases of CTS do not have an obvious cause there are a significant minority in which some other disease process can be seen to be contributing to the problem (with variable degrees of certainty). A full list of all the diseases which I have seen claimed to be associated with CTS appears at the bottom of this page but for many of these the 'association' is statistically doubtful. The mnemonic 'PRAGMATIC' has been suggested as a useful way of reminding oneself of the array of medical disorders which may underlie CTS and is one way of introducing some order to this epic list of diagnoses.
P - Pregnancy
R - Rheumatoid Arthritis (and other forms of arthritis)
A - Acromegaly
G - Glucose (Diabetes)
M - Mechanical (Fractures, anomalous muscles etc)
A - Amyloid
T - Thyroid (Under-activity)
I - Infection
C - Crystals (Gout and Pseudogout)
CTS is frequently seen with trigger digits and/or Dupuytren's contracture in the same hand and this group of conditions is discussed at length on a separate page.
If we accept the theory that the nerve damage is related to pressure within the carpal tunnel then three broad categories of causal linkage between another disease and CTS can be defined
Too much 'stuff' in the tunnel
An increase in tunnel contents can be due to the presence of a visible object - such as a tumour, or an 'extra' muscle located in the tunnel which is not there in most people, or may result from more widespread infiltration of the tissues within the tunnel by 'foreign' material - examples would include granulomatous infiltration in the various forms of mycobacterial infection in the carpal tunnel which have been reported, or the deposition of amyloid (a starch-like protein) within the carpal tunnel which occurs in patients with familial amyloidosis and in patients on long-term haemodialysis for kidney failure.
Too small a tunnel
Structural changes in the bony walls of the carpal tunnel resulting from injury or arthritis clearly have the capacity to physically narrow the tunnel.
Unusually susceptible nerve
A more subtle possibility is that the median nerve itself may become more susceptible to damage, and less able to cope with the 'normal' stresses of life in the carpal tunnel as a result of more widespread nerve disease. This would account for a higher incidence of CTS in diabetes and in most forms of peripheral neuropathy. Another example of this might be the slightly contentious entity of 'double crush' syndrome in which it is suggested that a lesion in the neck predisposes the median nerve to carpal tunnel syndrome.
Reported associations
The following list is drawn from my collection of papers and case reports and is an indiscriminate list of conditions which have been reported in association with CTS. There is some duplication because of differences in terminology used by different authors for the same condition. In many of these disorders the evidence for a true causal link between the disorder and CTS is shaky - CTS can clearly occur coincidentally 'in association with' anything! Those associations which I feel are important are highlighted.
Aberrant lumbricals + tenosynovial degeneration
Abnormal lumbrical anatomy
Abnormal palmaris longus
Accessory palmaris brevis muscle
Acromegaly
Acute calcific periarthritis (hydroxyapatite)
Acute calcifying tendonitis
Acute CTS in hemophilia
Acute intraneural haematoma from haemangioma
Adiposis dolorosa
Alcoholism
ALS/Cerebellar ataxia
Amyloidosis
Anabolic steroid use
Anomalous accessory/duplicated FDS
Anomalous muscle, not clearly identified
Ascending tenosynovitis from distal hand injury
Athetoid-dystonic cerebral palsy
Bifid median nerve with accessory canal within carpal tunnel
Bifid median nerve with one branch penetrating FDS tendon
Bifid reversed palmaris longus
Bilateral palmaris profundus tendons
Bony abnormality of distal radius
Burns
Bursitis
Calcareous mass in tunnel
Calcific periarthritis
Calcific tendonitis
Calcification in deep radio-carpal ligament
Calcium deposition in carpal tunnel
Carcinoma of larynx
Carpopedal spasm
Chondrocalcinosis (Pseudogout)
Congestive cardiac failure
Cushings disease
Cutaneous connective tissue disease
De Quervain's disease
Degenerative cyst in carpal canal
Dermatomyositis
Diabetes
Displaced scaphoid fracture
Disseminated angiomatosis (Klippel-Trenaunay Syndrome)
Dupuytren's contracture
Dyschondroplasia
Ectopic calcification deep to flexor retinaculum
Eosinophilic fasciitis
Familial
FAP type 2 variant - gene identified
Fibrolipomatous hamartoma
Fibromyositis at wrist
Flex dig superfic indicis muscle in canal
Flexor digitorum sublimis in carpal canal
Ganglion (motor branch only)
Ganglion of wrist
Giant cell arteritis of the median artery
Gout - tophaceous deposits on median nerve
Gout (without tophi)
Granulomatous tenosynovitis from Sporothrix schenckii
Growth hormone abuse
Guinea worm infestation
Haemangioma of the median nerve
Haematoma in anomalous lumbrical
Haematoms secondary to warfarin therapy (acute CTS)
Haemophilia
Haemorrhage (Haemophilia/Anticoagulants)
Herpes zoster
Heterotopic ossification in carpal tunnel
Histoplasmosis
Hurlers syndrome
Hyperlipidaemia
hypertension/Beta-blockers
Hyperthyroidism (Graves)
Hypertrophic arthritis carpus
Idiopathic calcium phosphate mass in tunnel
Infection (of tendon sheaths after penetrating injury)
Insect sting (swelling of hand_
Interleukin 2 therapy
Intraneural perineurioma of median nerve
Kienbocks disease, osteochondrosis of the lunate
Lactation
Lateral humeral epicondylitis
Leprosy
Leri's Pleonostosis
Leukaemia
Light chain amyloidosis
Lipfibroma of flexor tendon sheath
Lipofibroma of the median nerve
Lithium therapy
Liver transplantation, esp for PBC in women
Lumbrical muscles in tunnel
Lumbrical origin in forearm!
Lyme Disease
Madelung's deformity
MAOI inhibitors (tranylcypromine)
MCTD and trigeminal neuropathy
Median artery thrombosis
Median nerve tumours
Mucolipidosis III, Maroteaux Lamy
Multiple myeloma
Multiple sclerosis
Mycobacterium Kansasii
Mycobacterium Szulgai
Mycobacterium terrae
Mycosis fungoides
Myxoedema (Hypothyroidism)
Neurofibroma in tunnel with macrodactyly
Neurofibroma of median nerve
Neurofibromatosis
Obesity
Osteoarthritis
Osteochondritis dissecans
Osteophyte
Ovariectomy
Palmar flexor sublimis muscle (index)
Palmaris longus anomalies
Parathyroid adenoma
Periostitis
Pernicious anaemia
Persistent median artery
Persistent median artery (unthrombosed)
Peyronies disease
Polycythaemia rubra vera
Polymyalgia Rheumatica
Polymyositis
Pregnancy
Protease inhibitor use in AIDS therapy
Pseudogout/Pyrophosphate arthropathy
Psoriasis
Puff adder bite
Pure motor CTS due to ganglion
Radial artery cannulation
Radiation therapy
Raynaud's disease
Recurrence due to a median artery aneurysm
Reversed palmaris longus muscle
Rheumatoid arthritis
Rheumatoid Arthritis+Gout
Rotary subluxation of scaphoid
Rubella
Rupture of palmaris longus tendon
Sarcoidosis
Scleroderma
Secondary hyperparathyroidism (calcific deposit in wrist)
Severe head injury
Shoulder hand syndrome
Shoulder periarthritis
SLE
Spontaneous carpal tunnel haemorrhage
Stonefish envenomation
Synovial cyst
Syphilis
TB tenosynovitis in HIV patient
Tenosynovitis
Tietzes disease
Tophaceous gout
Toxic oil syndrome
Toxic shock syndrome
Trigger finger
Tuberculoid leprosy
Tuberculosis
Tumescent fluid or iv overload (see letters Worland + Duncan)
Tumoral calcinosis
Upper limb hypertrophy
Vibratory angioedema
Wrist fractures
Wrist/forearm burns (non acute)
Revision date - 26th June 2013
