Summary: | Carpal tunnel syndrome (CTS) presentation is usually classic but cold-related Raynaud's phenomenon (RP)-like symptoms were described in CTS and more commonly in the injured hand (HI). The work presented in this thesis is divided into two domains; the first aims to extend understanding of the response of the hand to cold in CTS and HI using two processes. [1] The modified cold provocation test (CPT) validated in a group of controls and both primary and secondary (vibration induced) RP subjects. Both hands were immersed in a 12°C water bath and the digital temperature recorded every 6 seconds using thermocouples until the digital temperature dropped to 15°C. The hands were then removed and allowed to passively re-warm. Baseline temperature (difference between the ambient temperature and the digital temperature), T30sec (temperature gain in the first 30 seconds post-cooling) and T5°C (time required to gain 5°C) were assessed. [2] Laser Doppler Imaging (LDI), a well-established method for investigating skin microcirculation with an endothelial challenge (facilitated by iontophoresis delivery Sodium Nitroprusside and Acetylcholine). The second domain centred on the management of CTS and in particular outcome assessment of conservative versus surgical treatment in registrar and nurse practitioner CTS clinics in a community hospital. Data on 86 controls, 31 primary RP and 59 secondary RP were collected. In the control group the baseline temperature was >6°C, which was higher than the primary and secondary RP groups (p-value <0.05, sensitivity 79%, 78%, specificity 43%, 45%, inter-class correlation 53%, 49%); T30sec in secondary RP was >1.8°C, which was higher than controls and the primary RP groups (p value <0.001, sensitivity 70%, 71%, specificity 76%, 79%, inter-class correlation 3%, 40%); and T5°C in primary RP was >300 seconds, which was longer than that of the controls and secondary RP groups (p-value <0.001, sensitivity 64%, 61%, specificity 70%, 64%, inter-class correlation 70%, 70%); data given for left and right hands respectively. CPT and LDI studies were undertaken on 60 controls and 60 CTS patients pre-operatively and repeated on 40 subjects 5-7 months post-decompression. Post-operatively, the baseline temperature increased by 1.5°C (p-value <0.05) in both hands and 2.5°C (p-value <0.001) in the median nerve supplied digits, T5oC was reduced in the hands (pre- versus post-operative from 474 to 348 seconds) (p-value 0.06) and from 468 to 273 seconds in the median nerve supplied digits (p-value 0.01). Endothelial dependent and independent control at mean and maximum pre- and post-cooling perfusion was significantly depressed (p value 0.05) post-cold exposure in the control group. LDI limited to the dorsum of the hand identified no significant difference pre- and post-operatively (p-value >0.05). HI subject recruitment was challenging: the absence of a financial incentive and the possible income loss during working days for a young working cohort might have contributed to the poor recruitment. Of the 60 subject targets only 14 recruited and the injury severity varied widely between the recruits; the data gathered through CPT and LDI in this group did not show a significant difference from that collected in controls. CTS management audits on 74 subjects in a nurse-led clinic and 173 subjects in a registrar-led clinic identified a high failure rate of the conservative management (60%) at 6 months follow up in both clinics with unclear success predictors suggesting an extra burden on clinics providing decompression surgery.
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