Vibrotactile sense in patients with diabetes and carpal tunnel syndrome.

AIM: To evaluate vibration perception thresholds of patients with and without diabetes, before and after surgical carpal tunnel release. METHODS: In a prospective study, 35 consecutive patients with diabetes and carpal tunnel syndrome were age and gender matched with 31 patients without diabetes having idiopathic carpal tunnel syndrome. Preoperatively, 6, 12 and 52 weeks after surgery, the vibration perception threshold of the index and little finger (median and ulnar nerve, respectively) was measured at seven different frequencies (8, 16, 32, 64, 125, 250 and 500 Hz). RESULTS: At several frequencies, patients with diabetes and carpal tunnel syndrome demonstrated significantly impaired vibration perception thresholds of both the index and the little finger, before as well as after carpal tunnel release, compared with patients without diabetes with idiopathic carpal tunnel syndrome. After surgery, the overall sensibility index improved for the index finger [patients with diabetes and carpal tunnel syndrome (0.79 to 0.91, P < 0.001), patients without diabetes with idiopathic carpal tunnel syndrome (0.91 to 0.96, P > 0.05)] as well as for the little finger [patients with diabetes and carpal tunnel syndrome (0.82 to 0.90, P < 0.008), patients without diabetes with idiopathic carpal tunnel syndrome (0.95 to 0.99, P < 0.05)]. For the index finger, the sensibility index improved to a significantly higher degree for patients with diabetes and carpal tunnel syndrome not having signs of peripheral neuropathy (0.83 to 0.95, P < 0.001) compared with those with neuropathy (0.74 to 0.84, P < 0.02). Vibration perception threshold correlates with age of both patients with diabetes and carpal tunnel syndrome and patients without diabetes with idiopathic carpal tunnel syndrome, while no relationship was found based on duration of diabetes. CONCLUSIONS: Vibrotactile sense is significantly impaired in patients with diabetes before and after carpal tunnel release compared with patients without diabetes. However, patients with diabetes obtained significant recovery of vibration perception threshold, particularly those without peripheral neuropathy.

Health-related quality of life in diabetic patients with carpal tunnel syndrome.

AIMS: To determine health-related quality of life (HRQL) in diabetic and non-diabetic patients with carpal tunnel syndrome (CTS) before and after surgical treatment. METHODS: In a prospective study, 35 consecutive diabetic patients with CTS were age and gender matched with 31 non-diabetic patients with idiopathic CTS. At baseline (preoperatively), 6, 12 and 52 weeks after surgical carpal tunnel release, patients completed the generic Short-Form 36 (SF-36) and the disease-specific Boston Carpal Tunnel Questionnaire (BCTQ). RESULTS: The SF-36 physical component scores at baseline were significantly reduced for diabetic (39+/-7.4) compared with non-diabetic patients (48+/-9.0) (P<0.05). Mixed model analysis demonstrated no differences in post-surgical improvement over time between diabetic and non-diabetic patients. The largest clinical effect was found for bodily pain (effect size 0.8). However, population norms were not reached for the diabetic patients. At baseline, no difference was found in mental component score, which deteriorated over time for diabetic patients. At baseline, BCTQ demonstrated that diabetic patients experienced more pronounced 'numbness in the hand' than non-diabetic patients. Large clinical improvements were found in both symptom severity (effect size 1.98-2.14) and functional status score (effect size 0.89-0.94) for both diabetic and non-diabetic patients, with no difference between the two patient groups. CONCLUSIONS: HRQL is impaired in diabetic patients with CTS compared with non-diabetic patients with CTS and population norms. However, diabetic patients experience similar symptomatic and functional benefits from carpal tunnel release as do non-diabetic patients.

Intraepidermal nerve fibre density at wrist level in diabetic and non-diabetic patients.

AIMS: Myelinated nerve fibre pathology has been demonstrated at wrist level in diabetic patients. We examined if quantification of intra-epidermal nerve fibre density (IENFD) in hairy and glabrous skin at wrist level could detect signs of subclinical small nerve fibre neuropathy. METHODS: In 35 diabetic patients who were age and gender matched with 31 non-diabetic patients, punch biopsies were obtained in conjunction with surgical carpal tunnel release. Biopsies were immunostained with anti-protein gene product (PGP) 9.5. The IENFD was quantified using manual counting by light microscopy. RESULTS: We could not demonstrate significant differences in IENFD between diabetic or non-diabetic patients. Additionally, no differences were found between patients with Type 1 and Type 2 diabetes or in diabetic patients with and without neurophysiologic signs of mild peripheral neuropathy. However, the IENFD was significantly higher in hairy skin compared with glabrous skin. Furthermore, the IENFD was significantly higher in females than in males and correlated with age, but not with duration of diabetes or glycated haemoglobin (HbA(1c)). CONCLUSIONS: In mild neuropathy no difference in IENFD at the wrist level could be detected between diabetic and non-diabetic patients. Independent of diabetes, we found IENFD to be higher in hairy skin compared with glabrous skin and higher in females than in males. These results must be taken into consideration when assessing small nerve fibre pathology in the upper extremity.

Biopsy of the posterior interosseous nerve: a low morbidity method for assessment of peripheral nerve disorders.

AIMS: The sural nerve is the commonest peripheral nerve biopsied to help in the diagnosis of peripheral neuropathy of unknown cause. However, associated complications limit its use. The aim was, as an alternative, to asses biopsy of the terminal branch of the posterior interosseous nerve (PIN) in the forearm. METHODS: PIN pathology was morphometrically quantified in 10 male patients with Type 2 diabetes and compared with six PIN biopsy specimens taken post mortem from male cadavers with no history of neuropathy or trauma. RESULTS: The PIN biopsy procedure provides a long (approximately 3 cm) mono- or bifascicular nerve biopsy with generous epineurial tissue and adjacent vessels. Our results show a significantly lower myelinated fibre density in subjects with diabetes [5782 (3332-9060)/mm(2)] compared with autopsy control material [9256 (6593-12,935)/mm(2), P < 0.007]. No postoperative discomfort or complications were encountered. CONCLUSIONS: A reduction in myelinated fibre density has previously been shown to be a clinically meaningful measure of neuropathy in diabetic patients. We demonstrate similar findings using the PIN biopsy. The PIN biopsy procedure fulfils the criteria for nerve biopsy and was well tolerated by the patients. It may be a possible alternative to sural nerve biopsy to allow for diagnosis of neuropathy.

Vibrotactile sense in median and ulnar nerve innervated fingers of men with Type 2 diabetes, normal or impaired glucose tolerance.

AIMS: To investigate vibrotactile sense (large fibre neuropathy) at different frequencies in index and little fingers (median and ulnar nerves, respectively) of subjects with diabetes, or impaired (IGT) or normal glucose tolerance (NGT). METHODS: Vibration thresholds (tactilometry at seven frequencies (8, 16, 32, 64, 125, 250 and 500 Hz)) and median nerve function (electrophysiology) were examined in men (age 73.4 +/- 0.12 years; n = 58, mean +/- sd) with persistent NGT (n = 28) or IGT (n = 7) or with Type 2 diabetes mellitus (T2DM) (n = 23) for > 15 years. RESULTS: HbA1c was increased and vibrotactile sense (sensibility index) was impaired in index and little fingers in men with T2DM. Vibration thresholds were particularly increased at 16, 250 and 500 Hz in the little finger (ulnar nerve). T2DM subjects showed electrophysiological (gold standard) signs of neuropathy in the median nerve. Although subjects with persistent IGT had higher HbA1c, vibrotactile sensation and electrophysiology remained normal. HbA1c did not correlate with vibrotactile sense or electrophysiology, but the latter two correlated with respect to Z-score (sign of neuropathy) in forearm (NGT) and at wrist level (NGT and DM). CONCLUSIONS: Vibration thresholds are increased in the finger pulps in T2DM subjects, particularly at specific frequencies in ulnar nerve innervated finger pulps. Neuropathy is not present in IGT. Tactilometry, with a multi-frequency approach, is a sensitive technique to screen for large fibre neuropathy in T2DM. Frequency-related changes may mirror dysfunction of various receptors.

Sequelae following sural nerve biopsy in type 1 diabetic subjects.

OBJECTIVES: To detect post-operative sequelae of sural nerve biopsy. MATERIALS AND METHODS: A questionnaire mailed to type 1 diabetic patients (n = 24; male/female 23/1; reply n = 23) 2 years after biopsy. RESULTS: Type 1 diabetic patients (age 56 [11]; median [interquartile range]) had a long duration of diabetes (DM; 20 [19] years) and all had neuropathy. Three out of 24 patients developed infection (two superficial and one deep) and one had a post-operative bleeding. Less frequent pain among the patients were reported from one centre. About one-third or more of the patients still complained of pain, mostly mild, in the biopsy area and paraesthesia in the foot 2 years after surgery. More than two-thirds of the patients were reluctant for further biopsy; a crucial information in drug trial planning. CONCLUSIONS: Sequelae of a sural nerve biopsy occur in type 1 DM. The risk for wound infections should be considered.

Accuracy of Pre- and Postcontrast, 3 T Indirect MR Arthrography Compared with Wrist Arthroscopy in the Diagnosis of Wrist Ligament Injuries.

Background Magnetic resonance (MR) is the most important imaging technique to assess intra-articular pathology of the wrist. Among various MR imaging protocols, the diagnostic performance of indirect MR arthrography needs further investigation. Purpose The purpose of this study was to assess the diagnostic performance of pre- and postcontrast, 3 T indirect MR arthrography in the diagnosis of scapholunate intrinsic ligament (SLIL) and triangular fibrocartilage complex (TFCC) injuries, using wrist arthroscopy as reference standard. Patients and Methods We retrospectively evaluated consecutive patients with suspected SLIL or TFCC injury, who had indirect MR arthrography done before arthroscopy. Images were assessed independently by two senior radiologists. Results Arthroscopy of the 53 wrists demonstrated 16 Geissler stages II and III partial tears and 6 stage IV total SLIL ruptures. Central perforation of the TFCC was found in 24 wrists, and 12 wrists had an ulnar class 1B lesion. To detect any SLIL tear, accuracy was higher for the two observers using postcontrast indirect MR arthrography (0.77 and 0.72) than for precontrast MR imaging (0.60 and 0.60). No difference was found for total SLIL ruptures "0.85 and 0.89" versus "0.85 and 0.89." To diagnose class 1B TFCC injuries, accuracy was higher using postcontrast indirect MR arthrography (0.85 and 0.75) than for precontrast MR imaging (0.70 and 0.72). No difference in accuracy was demonstrated for TFCC central tears "0.75 and 0.75" versus "0.70 and 0.77." Conclusion Postcontrast images at 3 T indirect MR arthrography, compared with precontrast images, have an improved diagnostic performance for the overall detection of SLIL injuries and as well as class 1B TFCC tears. Level of Evidence This is a Level II, diagnostic study.

Arthroscopy of the proximal interphalangeal joints of the finger.

Cadaveric studies were carried out to evaluate the technique, portals and possible indications for arthroscopy of the proximal interphalangeal joints of the finger. We suggest horizontal placement of the hand instead of using a traction tower, as it is important to be able to flex the joint freely. The recommended arthroscopic portals are either between the central slip and the lateral bands of the extensor mechanism or between the lateral band and the collateral ligament. A blunt technique of introduction is used to avoid iatrogenic cartilage damage and possible digital nerve injury.