Quantification of variable palmar ligaments around the triquetrum-hamate joint determined by lunate type

The ligaments of the wrist are highly variable and poorly described, which is more obvious on the ulnar side of the wrist. Previous studies highlighted the potential differences within the ligaments of the wrist but no consensus has been reached. Poor tissue description and inconsistent use of terminology hindered the reproducibility of the results. Improved understanding of the morphological variations between carpal bones may facilitate improved understanding of the ligamentous structure within the wrist. This study aims to identify the potential variations between carpal bones that could be used to separate palmar ligamentous patterns around the triquetrum-hamate joint into subgroups within the sample population. Investigations were performed following a detailed nomenclature and a clear definition of ligamentous structures to facilitate detailed description and reproducible results. Quantitative analyses were conducted using 3D modelling technique. Histological sections were then analysed to identify the structure of each ligamentous attachment. Variable patterns of ligamentous attachments were identified. Differences were not only obvious between samples but also between the right and left hands of the same person. These identifications suggested that the palmar ligamentous patterns around the triquetrum-hamate joint are best described as a spectrum with a higher affinity of the triquetrum-hamate-capitate ligament and the lunate-triquetrum ligament to be associated with type I lunate wrists on one extreme and type II lunate wrists with the palmar triquetrum-hamate ligament, triquetrum-hamate-capitate ligament and palmar radius-lunate-triquetrum ligament attachments at the other extreme. Histological analyses confirmed pervious established work regarding the mechanical role of ligaments in wrist joint biomechanics. Also, there were no significant differences between the quantitative data obtained from the Genelyn-embalmed and unembalmed specimens (p>0.05). The current study demonstrated variable ligamentous patterns that suggest different bone restraints and two different patterns of motion. These findings support previous suggestions regarding separating the midcarpal joint into two distinct functional types. Type I wrists were identified with ligamentous attachments that are suggestive of rotating/translating hamate whilst type II wrists identified with ligamentous attachments that are suggestive of flexing/extending hamate motion based upon the patterns of the ligamentous attachments in relation to the morphological features of the underlying lunate type of the wrist. This opens the horizon for particular consideration and/or modification of surgical procedures, which may enhance the clinical management of wrist dysfunction.

The links between head injury and homelessness: A qualitative study

Background and aims: Head injury (HI) is a cause of cognitive impairment within the homeless population (Hwang et al, 2008). One study reported that over a 30-year period, the prevalence of hospitalised HI was 5.4 times higher in the homeless than in the general population (McMillan et al, 2015). This study explores the perceptions of homeless adults who have sustained a HI and their views regarding the relevance of HI to their homeless status. Methods: Participants were seven homeless adults with a moderate or severe HI. They were asked to talk about their journey to homelessness and in particular, to reflect on any perceived links between HI and their homeless status. The data were analysed using Interpretative Phenomenological Analysis (IPA). Results and conclusions: Emerging themes included: impairment following HI; substance misuse, feeling let down by services and difficult relationships with family. Evidence for the role of HI in precipitating and maintaining homelessness was found. Despite this, co-morbid difficulties complicate the picture. Four out of seven participants viewed substance misuse as their primary difficulty. This illustrates the need for in-depth assessment within this population in order to ensure that difficulties are fully understood and that the correct supports/ interventions are offered.