The Carpal Boss: Review of Diagnosis and Treatment

doi:10.1016/j.jhsa.2007.11.029

The Journal of Hand Surgery

Volume 33, Issue 3, March 2008, Pages 446-449

https://doi.org/10.1016/j.jhsa.2007.11.029 Get rights and content

It is not uncommon to find a protruding mass at the dorsum of the wrist. The carpal boss is a commonly overlooked condition of unclear etiology. Minor trauma and persisting os styloideum are among the suspected causes of the condition. Long-standing carpal boss can lead to osteoarthritic damage in some patients. Many diagnostic tools, such as a “carpal boss view” radiographic study or a technetium bone scan, are available to help differentiate carpal boss from other, more common, masses of the dorsal aspect of wrist. For years, excision of the mass has been a commonly described treatment, because conservative treatment does not always give relief of symptoms. However, the benefits of wide excision must be balanced by the risks of instability at the involved joints, leading to persistent, and potentially worsened, symptoms.

Section snippets

Characteristics of Carpal Boss

It is common to find a protuberance in the region of the dorsal second and third carpometacarpal joints during examination of the hand. The lesion is most often a ganglion and is asymptomatic, with complaints being on aesthetic grounds. Nonetheless, asymptomatic or symptomatic carpal boss must be considered in the differential diagnosis. Carpal boss is an uncommon condition, and the strong association between the presence of an accessory ossicle and carpal boss suggests that it represents an os

Diagnosis and Differential Diagnosis

Like a dorsal ganglion, the bony protuberance of carpal boss is most visible on volar flexion of the wrist (Fig. 2). However, the mass of carpal boss usually has a distinctly hard consistency, which can help distinguish it from dorsal ganglions (which tend to have a cystic consistency and can be transilluminated easily). Note, however, that the hard consistency of carpal boss may not be present in cases with overlying ganglion, inflamed bursa, or synovitis, and so diagnosis can be even further

Treatment and Discussion

Currently, there is no large study available regarding the efficacy of standard conservative treatment (nonsteroidal anti-inflammatory agents, corticosteroid injection, splint immobilization, and hand therapy) for symptomatic carpal boss. In a small sample of 13 patients, 11 patients had no relief of symptoms following corticosteroid injection.¹⁴ In another study of 9 patients, steroid injection did not provide notable long-term symptomatic relief for any of the patients.¹⁸ Most authors agree

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Cited by (57)

Well, well, what do we have here...
2023, FMC Formacion Medica Continuada en Atencion Primaria
Anatomy of the wrist and its variants of interest for the clinician (hunchback carpus, short ulna, carpal synostosis…)
2023, Revue du Rhumatisme (Edition Francaise)
L’anatomie du poignet est très variable, que cela entre dans les variantes de la normale ou qu’il s’agisse de franches anomalies constitutionnelles ou acquises. Toujours est-il que ces variables sont importantes à bien connaître car elles ont des conséquences cliniques et thérapeutiques. Cela va du simple carpe bossu qui est banal par sa relative innocuité et sa grande fréquence, aux anomalies de longueur et de forme de la radio-ulnaire distale qui peuvent être constitutionnelles ou acquises et alors souvent post fracturaires. Elles ont un retentissement important sur le fonctionnement global du poignet plus particulièrement en prono-supination et des conséquences dégénératives qui peuvent être très handicapantes. Enfin, le nombre d’os du carpe est assez variable : en moins lors des synostoses qui sont non exceptionnelles ou en plus lors des partitions carpiennes au cours de l’embryogenèse. Ces différentes modifications anatomiques sont détaillées ainsi que les conséquences pratiques qui en découlent.
The anatomy of the wrist is very variable, whether it falls within the variants of normal or whether it is a question of frank constitutional or acquired anomalies. Still, these variables are important to know because they have clinical and therapeutic consequences. This ranges from the simple hunchback carpus, which is commonplace for its relative harmlessness and high frequency, to anomalies in the length and shape of the distal radio-ulnar joint which can be constitutional or acquired and therefore often post-fracture. They have a significant impact on the overall functioning of the wrist, more particularly in prono-supination, and degenerative consequences which can be very disabling. Finally, the number of carpal bones is quite variable: less during synostoses which are not exceptional or more during carpal partitions during embryogenesis. These different anatomical modifications are detailed as well as the practical consequences that flow from them.
Gamma camera imaging (bone scan) in orthopedics: Wrist, elbow and shoulders
2022, Nuclear Medicine and Molecular Imaging: Volume 1-4
The upper limb consists of complex joints which are non-weight bearing but provide dexterity and are also subject to trauma. This chapter covers imaging of the upper limb primarily focusing on SPECT-CT which is essential when imaging the extremities with bone scintigraphy. The chapter is divided into the hand and wrist, elbow and shoulder. Imaging modalities used to evaluate the joints are described in detail, and the advantages and disadvantages of each are described. The pathologies covered are fractures, arthritis, impaction syndromes, impingement syndromes, infection and post-operative complications. SPECT-CT imaging protocol and acquisition parameters are also provided. The aim of this chapter is to equip the reader with all the necessary knowledge to be able to tackle reporting of complex upper limb SPECT-CT scans.
Endoscopic Resection of Carpometacarpal Boss and Synovectomy of the Second Carpometacarpal Joint
2019, Arthroscopy Techniques
Citation Excerpt :
This view compensates for the obliquity of the longitudinal axis of the metacarpal-capitate joint and optimizes the profiling of the os styloideum, which projects 30° to 40° dorsoradially.2 A technetium bone scan may be helpful in differentiating carpometacarpal boss from other, more common, masses of the dorsal aspect of wrist.5 Magnetic resonance imaging allows for detailed examination of bone and soft tissue abnormalities associated with a carpometacarpal boss, including the extent of degeneration of the involved carpometacarpal joint, the formation of intratendinous ganglion, and the presence of inflammatory bursitis.
Carpometacarpal boss is a symptomatic bony prominence on the dorsal surface of the wrist at the base of the second and/or third metacarpal. Wedge excision of the carpometacarpal boss is indicated if conservative treatment fails to relieve the symptoms. Complications of wedge resection include symptomatic recurrences and carpometacarpal instability. The purpose of this Technical Note is to describe the technical details of endoscopic resection of carpometacarpal boss and synovectomy of the second carpometacarpal joint. This may reduce the amount of bone and joint resection and risk of carpometacarpal instability.
Surgical treatment of carpal boss by simple resection: Results in 25 cases at a mean of 8 years’ follow-up
2017, Hand Surgery and Rehabilitation
Carpal boss is a symptomatic bony protrusion on the dorsal surface of the wrist at the base of the 2nd and/or 3rd metacarpal. The goal of this study was to assess the reliability and safety of simply resecting the exostosis. From 1994 to 2014, 29 cases of carpal boss were treated by simple resection. Twenty-five of these patients were subsequently assessed by telephone questionnaire at a mean of 8 years’ follow-up (range 1.1 to 20 years). There were no cases of recurrence; however, 1 patient reported carpometacarpal instability requiring fusion, 5 years after surgery. Eight of the 24 patients without fusion (33%) reported moderate episodic pain (visual analog scale [VAS] pain: mean, 2.3/10, range 1 to 4). Range of motion improved in 8 cases (33%), was unchanged in 11 (46%) and decreased in 5 (21%). Twenty patients (83%) had no functional impairment; 4 reported impairment during unusual hand movements. Fifteen patients considered themselves cured (60%), 9 considered their status improved (36%) and one – the patient who required fusion – considered his status unchanged. Patients were very satisfied with the procedure in 15 cases (60%) and satisfied in 10 (40%). In all cases, features of dysplasia were present and associated with secondary osteoarthritis limited to the area of impingement. The single failure was most likely due to excessive bone resection. Simple exostosis resection is sufficient to effectively treat carpal boss. Fusion should be reserved for the rare cases of secondary metacarpal instability.
Le carpe bossu est caractérisé par une protubérance osseuse à la face dorsale du carpe, à la base du 2^e et/ou 3^e métacarpien. Le but de cet article était d’évaluer la fiabilité et l’innocuité de l’exérèse simple de l’exostose. De 1994 à 2014, 29 carpes bossus ont été opérés par exérèse simple. Les patients ont été contactés par un évaluateur indépendant et ont répondu à un questionnaire téléphonique. L’évaluation a été réalisée en moyenne 8 ans après l’intervention (de 1,1 à 20 ans). Vingt-cinq patients ont pu être recontactés. Aucune récidive n’était déclarée, mais un patient présentait à cinq ans postopératoires une instabilité carpo-métacarpienne ayant nécessité une arthrodèse. Parmi les 24 patients non arthrodésés, 8 (33 %) rapportaient une douleur épisodique moyenne notée à l’échelle visuelle analogique (EVA) de 2,33/10 (de 1 à 4). La mobilité était considérée comme améliorée dans 8 cas (33 %), inchangée dans 11 cas (46 %) et diminuée dans 5 cas (21 %). Vingt patients (83 %) ne ressentaient aucune gêne fonctionnelle et quatre pour des gestes inhabituels. Les patients se considéraient guéris dans 15 cas (60 %), améliorés dans 9 cas (36 %) et inchangé pour le patient arthrodésé. Les patients étaient très satisfaits de l’intervention dans 15 cas (60 %) et satisfaits dans 10 cas (40 %). Dans tous les cas, il existait des éléments de dysplasie associés à une arthrose secondaire limitée à la zone de conflit. Le seul échec était certainement dû à une exérèse trop importante de l’exostose. La simple exérèse de l’exostose suffit pour traiter efficacement un carpe bossu, l’arthrodèse doit être réservée aux cas d’instabilité métacarpienne secondaire.
«Carpal boss»: One cause of wrist pain in primary care
2020, Semergen

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Review articleThe Carpal Boss: Review of Diagnosis and Treatment

Section snippets

Characteristics of Carpal Boss

Diagnosis and Differential Diagnosis

Treatment and Discussion

J Hand Surg

J Hand Surg

Ann Chir Main Memb Super

J Hand Surg

J Hand Surg

Le “carpe bossu”

Bull Mem Soc Nat Chir

The carpal boss: an overview of radiographic evaluation

Radiology

Borderlands of the normal and early pathological in skeletal roentgenology

Grenzen des Normalen und Anfänge des Pathologischen im Röntgenbild des Skeletts [Borderlands of the normal and early pathological in skeletal roentgenology]

Carpal boss caused by an accessory capitateCase report

Acta Orthop Belg

A survey of carpal and tarsal anomalies

J Bone Joint Surg

The condition of the os styloideum as attached to the III metacarpal; to the magnum; to the trapezoid

J Anat

The carpal boss: surgical treatment and etiological considerations

Plast Reconstr Surg

The styloid bone and carpe bossu disease

Am J Roentgenol Radium Ther Nucl Med

Review article
The Carpal Boss: Review of Diagnosis and Treatment