Compression neuropathies of the Upper Extremity
Authors:   , Westenberg Ritsaart Frederik 
Published: May 2023

This thesis is about compression neuropathies of the upper extremity. Compression neuropathies often occur in patients with a genetic and/or systemic predisposition for such a syndrome or after a trauma. In each chapter of this thesis different aspects of compression neuropathies in the upper extremity were assessed, such as anatomy and pathophysiology, risk factors and outcomes of revision surgery, and the impact of psychological and other factors on patient reported outcomes. In addition, we evaluated which factors are associated with the response rate to long-term follow-up studies of upper extremity diseases. In chapter one, we discuss several aspects of the anatomy and pathophysiology of nerve compression syndromes of the upper extremity. In paragraph 1.1, we assessed what the average size of the median nerve, ulnar nerve, and its corresponding branches in 18 fresh frozen cadavers. In paragraph 1.2, we assessed which factors are associated with the development of non-acute carpal tunnel syndrome (CTS) in patients who had conservative treatment of distal radius fracture. A CTR at least eight weeks after a distal radius fracture on the ipsilateral side was defined as non-acute CTR. In chapter two, we discuss revision surgery after CTR. Surgical transection of the transverse carpal ligament is the most effective treatment to treat carpal tunnel syndrome. However, in some cases of carpal tunnel syndrome symptoms persist or recur several weeks or months after surgical release. In this chapter we discuss the risk factors for revision surgery, the long-term outcome after revision surgery, and the difficulty in defining persistent and recurrent symptoms after CTR. In paragraph 2.1, the aims are to determine the rate of revision CTR in five urban hospitals over a period of 14 years and to assess what demographic, condition-related, and treatment related factors are associated with revision CTR. In paragraph 2.2, the aims were to evaluate the long-term patient reported outcomes (PROM’s) after revision CTR. In paragraph 2.3, the goal was to evaluate the current clinical practice on and thoughts about the definition and treatment of recurrent and persistent CTS in the Netherlands. In chapter three, we describe the causes of ulnar tunnel syndrome (UTS), the incidence of ulnar tunnel release (UTR), and identify factors associated with long-term patient reported outcomes after UTR. In chapter four, we discuss psychological factors in nerve compression syndromes and disease of the upper extremity. Knowledge about differences between patient, disease, and psychological characteristics of patients that choose for surgi-cal treatment or splint treatment for CTS may be helpful during patient counseling and evaluation of research regarding CTS. In paragraph 4.1, we assessed what the difference in baseline patient, clinical, and psychological characteristics are between patients scheduled for splint treatment and patients scheduled for CTR. In paragraph 4.2, we assessed if a brief mindfulness-based intervention can improve pain intensity, emotional distress, and state anxiety, and if use of such an intervention is feasible and acceptable for patients with upper extremity disease in a busy orthopaedic clinic. In chapter 5, we assessed what factors are associated with response rates for long-term follow-up questionnaire studies in upper extremity surgery.