A rare case of carpal boss lesion with an overlying ganglion cyst: case report and literature review

Carpal boss is a bony protrusion on the dorsal aspect of wrist quadrangular joint. The exact cause and prevalence are not well understood. Most of the patients are asymptomatic, although some experience pain, bony prominence, restricted mobility, and joint instability in sever neglected cases. We are presenting a case of a 24-year-old male had chronic dorsal wrist pain with bony prominence appearance underwent surgical excision of a carpal boss lesion in concomitant with soft tissue ganglion cyst over the carpal boss after failed conservative management, resulting in significant symptom improvement and restored range of motion. Carpal boss lesion is a common condition that can be undiagnosed due to asymptomatic presentation or the presence of overlying soft tissue pathology as ganglion cyst. Although conservative treatment is helpful in some patients, most symptomatic carpal boss lesion patients eventually need surgical excision.

Dorsal Wrist Carpal Boss Impingement-Dynamic Ultrasound to the Rescue!

The "carpal boss" is a variant present in 19% of the population according to cadaveric studies but becomes symptomatic in only 1% of cases. With the rising popularity of "yoga," which includes prolonged hyperextension at the wrist joint with weight bearing, an increasing number of individuals with silent carpal boss present with dorsal wrist pain due to impingement over the dorsal soft tissues by this innocuous bony protuberance. This warrants the attention of radiologists and clinicians while dealing with wrist pain. It can be challenging to identify this bossing on routine radiographs, necessitating special views. We describe the use of dynamic ultrasound in diagnosing "symptomatic" carpal boss, the effects of which become even more evident on imaging during hyperextension-the triggering movement.

Surgical treatment for persistent second carpometacarpal joint pain

The purposes of this study were to demonstrate the clinical characteristics of patients with persistent second carpometacarpal (CMC) joint pain without bony abnormalities known as the carpal boss, and to assess the clinical efficacy of surgical stabilization of the second CMC joint. Eleven patients had persistent wrist pain with characteristic symptoms, including tenderness over the second CMC joint, increased symptoms when the involved hand was placed on the ground or gripped strongly with the involved hand, a positive metacarpal stress test and temporary pain relief with the intra-articular injection of the lidocaine. The patients underwent arthrodesis of the second CMC joint. All cases showed radiologically confirmed fusion of the second CMC joint. At the final followup examination, 10 of 11 patients resulted in satisfactory clinical outcomes, excepting one patient with remnant pain and restricted range of wrist motions. This report highlights the importance of conducting a careful assessment of patients who present with persistent second CMC joint pain without the bony abnormalities, such as carpal bossing. Surgery to stabilize the second CMC joint may be an option to improve their symptoms when conservative treatment fails.

The Fourth Extensor Compartment Artery Vascularized Bone Graft of the Distal Radius for CMC Fusion in the Treatment of Carpal Boss: A Case Report

BACKGROUND

Carpometacarpal joints can be affected by traumatic or degenerative pathology. Although different techniques have been described to treat these conditions, most authors agree that arthrodesis is an effective treatment modality. Vascularized bone grafts of the distal radius have been used to treat carpal conditions, such as scaphoid nonunion or Kiënbock disease, and they have been shown to have several advantages over nonvascularized bone grafts.

METHODS

We report a case of a carpal boss in a female patient treated with an arthrodesis of the second and third carpometacarpal joints by using the fourth extensor compartment artery vascularized bone graft.

RESULTS

At 6 weeks postoperative bone union was achieved. At 2 years follow-up the patient was able to perform daily life activities without pain.

CONCLUSIONS

The fourth ECA VBG with reverse blood flow from the dorsal intercarpal arch allowed the graft to reach the CMC. A solid fusion was obtained at 6 weeks due to the biological advantage of the VBG.

That's my STYLEoideum - Symptomatic os styloideum in an adolescent male

We present a 15-year-old male patient with persistent localized pain on the dorsal side of the left wrist between the base of the 2nd and 3rd metacarpal bones and over the third carpometacarpal joint. It was diagnosed as an accessory metacarpal bone -Os styloideum. This entity may be detected on plain radiographs and in ultrasound examination and is often asymptomatic. Symptomatic os styloideum occurs more frequently in the dominant hand and may be treated conservatively with corticosteroid infiltration. A palpable prominence on the dorsal side of the wrist and focal pain evoked anxiety of the adolescent patient who searched medical consultation. In the clinical examination, a bony protrusion was confirmed and different possible diagnoses have been considered. After treatment with a corticosteroid infiltration of the third carpometacarpal joint under fluoroscopy the pain resolved completely. We would like to draw attention of clinicians and radiologists to this rare anatomical variant that normally is asymptomatic, and therefore not immediately recognized. Acquaintance with this entity and its early detection may lead to conservative treatment instead of surgical excision. A comprehensive literature search, review and discussion about os styloideum are provided in the article.

Imaging Findings at the Quadrangular Joint in Carpal Boss

A carpal boss was initially described as a bony, sometimes painful mass at the quadrangular joint. Clinical examination and plain radiography will usually reveal the diagnosis. US and CT may add information. MRI may illustrate a variable bony morphology and additional bony and soft tissue pathologies. Bone marrow edema shows a significant correlation with a painful carpal boss. Hence, MRI may be of additional diagnostic value in patients with persistent pain and preoperatively. This paper presents a review of the anatomy and pathology in carpal boss. The merit of each imaging modality - in particular MRI - is mentioned.

Characterization and Epidemiology of the Carpal Boss Utilizing Computed Tomography

Background The carpal boss is an osseous protuberance occurring variably along the dorsum of the second or third metacarpal base, lacking a standardized definition. Aim We sought to characterize the dorsal second and third carpometacarpal joints in the general population on computed tomography (CT) to better define this variant anatomy. Patients and Methods A total of 129 wrist CT studies were reviewed. Note was made of the dorsal second/third carpometacarpal osseous anatomy, the presence of regional bursitis or tenosynovitis, and relationship of the extensor carpi radialis brevis attachment to the base of the third metacarpal. Results Out of the 129 wrists, 106 (82.2%) demonstrated a dorsal protuberance arising from the base of the third metacarpal, in isolation. Out of the 129 wrists, 14 (10.9%) lacked a dorsal protuberance or nonunited ossicle at the level of the second or third carpometacarpal joint. Out of the 129 wrists, 9 (7%) wrists demonstrated more complex anatomy-8 wrists (6.2%) with a dorsal protuberance at the base of the third metacarpal seen in combination with an adjacent nonunited ossicle and/or dorsal protuberance arising from the capitate, and 1 wrist (0.8%) with an isolated ossicle at the base of the third metacarpal. Of these nine wrists, eight (6.2%) demonstrated arthritis at the resultant pseudoarticulation(s). Conclusion The majority of wrists demonstrated an isolated protuberance arising from the dorsal base of the third metacarpal, with a small minority with a nonunited ossicle at this level and/or dorsal protuberance of the capitate. The presence of secondary arthritis (8 out of 129 wrists, 6.2%) may reflect a pain generator. Level of Evidence Cross-sectional study; level 2.