Ulnar impaction syndrome occurs when excessive load across the ulnocarpal joints results in pathologic changes, especially over the articular surface of the ulnar head and proximal ulnar corner of the lunate. The 2 main surgical options in ulnar impaction syndrome are ulnar shortening osteotomy and wafer procedure, whether open or arthroscopically, to decompress the ulnocarpal joint load. However, all of these techniques have their shortcomings and drawbacks. The current study demonstrates a novel technique to decompress the ulnocarpal joint load: the "reverse wafer procedure" for ulnar impaction syndrome. In this surgical technique, we resected the proximal ulnar side of the lunate instead of partial resection of the thin wafer of the distal ulnar head dome in the standard wafer procedure. This technique avoids iatrogenic central tear of triangular fibrocartilage and distal radioulnar joint portal arthroscopy, which is technically demanding while preserving the distal radioulnar joint.
Sex assessment is an essential step in person identification, both in forensic and anthropological contexts. Many parts of skeletal remains such as skull, pelvis and long bones have been proven to be useful in determining sex. However, literature has shown that short bones such as carpal bones are also sexually dimorphic. In the last few years, there was an unpublished study using lunate, scaphoid and hamate from bone collection in Northern Thailand to create 6 discriminant equations to assess sex. The objective of this study was to investigate the application of those equations in the sample from other parts of Thailand.
Studies on the wrist joint have shown two types of the carpal bone lunate. In type II lunate there is a facet on the medial side of the lunate for articulation with the proximal pole of the hamate; such a facet is absent in type I lunate. Type II lunates have different kinematics, are more prone to clinically relevant degenerative changes in the hamato-lunate joint and are an uncommon cause of ulnar-sided wrist pain. Ninety plain radiographs showing postero-anterior views of the wrist (52 right and 38 left wrists) were studied in a population of Malays from Malaysia (mean age 48 years; age range 23 to 67 years) to determine the incidence of type I and type II lunates. Our findings were compared with those in other reports in the literature. In Malays, only 24 wrists (26.7%) showed a type II lunate compared to a reported incidence of 50% or more in populations from the Western world. Such a low incidence of type II lunate has not been reported before and may represent a genetic variation in Malays. Consequently, osteoarthritis of the hamate or lunate may play a less significant role in causing ulnar-sided wrist pain in Malays. In conclusion, the prevalence of type II lunate might vary in different population groups and further studies could be necessary to confirm this observation.
A 30-year old male right handed professional tennis player complained about reduced athletic performance, chronic pain and restricted extension of his right wrist. Lateral radiograph of the right wrist demonstrated an osteophyte projecting from the dorsal lip of the lunate bone. The presence of an osteophyte on the lateral radiograph of the lunate along with the history, clinical examination, intra-operative findings, and post-operative satisfactory result made the diagnosis of dorsal luno-capitate impingement syndrome reasonable.