The symptomatic carpal boss. Is simple excision enough?

Recurrence rate and patient-reported outcomes after wedge excision of carpal boss

The treatment of carpal boss is primarily conservative. Surgical treatment by performing a wedge excision of the bony protrusion, is possible. However, a common belief exists that carpal boss should not be operated because of the high recurrence rate. Additionally, little is known about the clinical outcomes of wedge excision and the preferred post-operative treatment. Patients with carpal boss and persisting pain who underwent wedge excision after conservative treatment were included. They received questionnaires before and three months after surgery. The primary outcomes were pain and hand function measured using patient-reported wrist evaluations (PRWE). Secondarily, recurrence, patient satisfaction and time until return to work were evaluated. These clinical outcomes were also compared between patients who received a plaster splint or a pressure dressing post-operatively. 76 patients were included. Three months after surgery, a significant improvement in PRWE was seen, for both pain and function. A re-operation rate for recurrent carpal boss of 13% was observed. After three months, 58% of patients were satisfied and 73% had returned to work. While no differences in clinical outcomes were found, patients were more satisfied after receiving a pressure dressing than a plaster splint post-operatively. The current study demonstrates encouraging early outcomes after wedge excision, and a low recurrence re-operation rate. Furthermore, a pressure dressing seems preferable post-operatively compared to a plaster splint.

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.

Arthroscopic Management for Carpometacarpal Boss of Third Joint and Synovectomy: Technique and Case Report

The carpometacarpal boss (CMCB) is painful bony prominence in the dorsum of the hand that can lead to functional and aesthetic impairment. Nonoperative methods are the management of choice, achieving good outcomes. However, operative management could be an alternative in the absence of improvement. Nevertheless, open procedures are more likely to be done, but there are complications, and it is more aggressive to the soft tissue. The use of arthroscopic techniques has increased in the last decade, being a safe alternative for CMCB management. It has the advantage of being a minimally invasive technique, allowing the early range of motion. This minimally invasive method allows synovectomy and preserves tendon attachments, achieving good functional outcomes. This case report presents an arthroscopic technique for managing the middle finger CMCB.

Carpometacarpal Arthrodesis for Traumatic Carpal Boss Among Combative Athletes

Among professional combat athletes, excessive and repetitive trauma to the carpometacarpal (CMC) joints may cause instability, arthritis, and the development of traumatic carpal boss. If nonoperative management is unsuccessful, CMC joint arthrodesis with iliac crest bone graft and supplemental Kirschner wire fixation is a reliable surgical option that results in pain-free return to full competition. From 2002 to 2015, 15 professional athletes with 17 symptomatic carpal bosses were treated with CMC joint arthrodesis after unsuccessful nonoperative management. The operative technique included decortication of the articular surface of the CMC joints, insertion of iliac cancellous and corticocancellous slot grafts, and secure Kirschner wire fixation. Patient charts and postoperative imaging were retrospectively reviewed. Outcome measures included grip strength, pain relief, fusion rate, return to competition, and complications. Mean age at the time of surgery was 28.2 years (range, 21-39 years). The radiographic fusion rate was 100% and occurred at a mean of 7.5 weeks. Mean return to competition occurred at 6 months. Grip strength at final follow-up increased 32% from preoperative level and was 90% of the grip strength of the contralateral hand. Postoperatively, 2 patients had sagittal band ruptures, and 1 patient had a fifth metacarpal fracture. No revision procedures were performed. All patients undergoing CMC arthrodesis had successful fusion, without the need for revision surgery and with return to full competition. For professional fighters, CMC arthrodesis with iliac crest autograft is a safe and effective surgical method for treating symptomatic traumatic carpal boss. [Orthopedics. 2022;45(1):e17-e22.].

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.

Surgical treatment of carpal boss by simple resection: Results in 25 cases at a mean of 8 years' follow-up

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.

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.

Diagnosis and Treatment of Symptomatic Carpal Bossing

CONTEXT

Carpal bossing is an osseous formation at the dorsal portion of the quadrangular joint, which rarely becomes symptomatic. However, in some patients it causes pain, restricted mobility and can lead to complications like tendon rupture, inflammatory and degenerative joint disease.

AIM

In this article, we present our experiences with this rare disorder in order to improve diagnostic and therapeutic proceedings.

SETTINGS DESIGN

This is a multicenter and interdisciplinary observation made by orthopaedic surgeons and radiologists in the years 2010 to 2015. Retrospective observational study. The follow up period was 2 years.

MATERIALS AND METHODS

In the observed time period, eight patients were diagnosed with symptomatic carpal bossing. Symptoms were pain at palmar flexion and limited mobility of the wrist in combination with a palpable protuberance over the quadrangular joint. All patients underwent X-ray, CT and MRI examinations. A conservative treatment strategy was initiated for 6 weeks in all patients, followed by a wedge resection when symptoms were persisting and disabling.

RESULTS

After the conservative treatment schedule, five patients were asymptomatic. Three patients had persisting pain and were thus recommended for surgery. In the postoperative course, two patients were asymptomatic. One patient developed a type 1 complex regional pain syndrome (CRPS) in the first postoperative year, which was successfully treated with pain-adapted physiotherapy, pharmacotherapy with analgesics and calcitonin, and a triple CT-guided thoracic sympathetic nerve blockade.

CONCLUSION

Carpal bossing is a mostly asymptomatic entity, which in our experience gets symptomatic due to direct trauma or repetitive stress, especially in competitive racket sports players. It can be diagnosed by thorough clinical examination and multimodal diagnostic imaging. Conservative treatment comprises an excellent prognosis, however surgery, either wedge resection or arthrodesis, must be considered if the response is not positive after 6 weeks.

Attrition or rupture of digital extensor tendons due to carpal boss: report of 2 cases

We present 2 cases that demonstrate the potential for tendon involvement in the presence of a carpal boss. In the first, a patient presented with tendon rupture without antecedent pain. In the second, pain and tendon irritation prompted magnetic resonance imaging that revealed tendon fraying, which was confirmed at surgery. These cases illustrate the potential for tendinous sequelae of a carpal boss. Advanced imaging may be considered when tendon irritation is clinically suspected. Attention to the possibility of tendon rupture in the setting of an otherwise asymptomatic carpal boss is advised.

Arthroplasty of the scaphoid-trapezium-trapezoid and carpometacarpal joints

Resection arthroplasty is an old, and yet reliable, solution for the isolated osteoarthritis (OA) of some joints of the hand. With complication low rates, this technically undemanding option is ideal for scapho-trapezial-trapezoidal joint OA, as well as for the OA of the carpometacarpal joints of the fingers. This paper reviews its indications, surgical technique, and results.

Spontaneous rupture of the extensor carpi radialis brevis in a 51-year-old man: case report

Dorsal hand osteophytes are common findings in the general population, frequently presenting with dorsal pain and treated with surgical excision. We report the spontaneous rupture of the extensor carpi radialis brevis in association with a previously asymptomatic dorsal scaphoid spur. Following conservative management, surgical excision of dorsal hand osteophytes should be considered for both resolution of pain and prevention of attritional tendon rupture.

Dorsal wrist mass: the carpal boss

The carpal boss is an osseous overgrowth that is occasionally mistaken for a ganglion cyst. This report highlights the case a 36-year-old patient who was originally diagnosed by his primary care physician with a ganglion cyst and was sent to an orthopaedist for aspiration. Upon further evaluation with a plain radiograph, the dorsal wrist mass was found to be a carpal boss. The patient was treated with rest and a wrist brace, and was informed that a corticosteroid injection or surgical excision would be necessary if conservative treatment failed. The patient was asymptomatic on follow-up and invasive procedures were not necessary.

Carpal boss in an adolescent: case report

Carpal boss is a relatively uncommon cause of pain and swelling on the dorsum of the wrist and usually presents in adult patients. However, it is occasionally seen in adolescents. We describe an unusual case of a 15-year-old girl with a carpal boss treated surgically after failed conservative treatment. Surgical excision of the carpal boss resulted in relief of symptoms with no complications.

Carpal boss: effect of wedge excision depth on third carpometacarpal joint stability

PURPOSE

We hypothesize that carpal-metacarpal (CMC) instability after carpal boss wedge excision is not caused only by damage to the dorsal ligament but mainly depends on the depth of the bony resection.

METHODS

To test our hypothesis, this study analyzes the effect of wedge excisions with different depths (0, 15%, 35%, 55% of the third CMC joint) and the effect of different forces (0, 50, 100 N.m) on the stability (measured as the passive flexion) of the third CMC joint using 12 fresh-frozen human cadaver wrists. The passive flexion is defined as the increase in angular motion of the third CMC joint and represents change in stability during flexion of the joint.

RESULTS

The results show that the mean passive flexion measured in the wedge excisions of 15% and 35% of the joint did not differ from that of neutral controls. Joints analyzed after a 55% wedge excision showed a significant increase in angular motion (increased passive flexion). This relates to the 50 N.m as well as the 100 N.m loaded test position.

CONCLUSIONS

This study shows that a wedge excision of clinically applicable depth of 35% does not create instability during flexion of the third CMC joint when loaded with physiologically relevant forces. Yet an extended and hardly clinically relevant 55% wedge excision results in a change in stability of the joint. To prevent instability when performing a wedge excision for symptomatic carpal boss, care must be taken to avoid excisions that exceed 35% of the third CMC joint.

The preliminary results of treatment of symptomatic carpal boss by wedge joint resection, radial bone grafting and arthrodesis with a shape memory staple

There is no consensus regarding the aetiology or treatment of carpal boss. Recurrences or carpometacarpal instability is reported after simple resection. Carpometacarpal arthrodesis has been proposed as a primary treatment and after failure of simple resection. This paper reports the results at a mean follow-up of 17 (range 13-28) months of treatment by wedge-shaped joint resection, corticocancellous radial bone graft and arthrodesis with a shape memory staple of seven of 32 patients who presented with a painful carpal boss. The study group included five women and two men of mean age at operation 29 (range 18-40) years. Fusion was achieved in all cases and all patients were pain free at follow-up. No complications occurred and all the patients were pleased with the aesthetic aspect of the treatment.

The carpal boss: review of diagnosis and treatment

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.

[Numerical variants and congenital fusions of carpal bones]

The number of carpal bones may be increased or decreased by the fact of anatomical variants or true congenital anomalies. Numerical increment arises from additional or from split bones. Over twenty accessory carpal bones have been described but the commonest are the os centrale carpi, the os radiale externum, the triangular bone and the styloideum bone. Additional carpal bones usually result from a failure of fusion of their ossification centers. A congenital origin is not clearly established for all these ossicles. The scaphoid and lunate may split into two or three bones and several cases of bipartite hamulus of the hamatum have been reported. A carpus with only seven bones results from the congenital absence of a normal bone, which mainly affects the scaphoid, lunate and triquetrum, or from a synostosis between two carpal bones, usually the lunate and triquetrum. Congenital fusions originate from an absence of joint cavitation into the embryo and chondrification of the joint interzone. Numerical carpal variants are uncommon as independent entities but occur with a relative high frequency in association with complex malformations of the hand. These anomalies are detectable on plain radiographs of the wrist, but CT-scan and MR-Imaging are useful to differentiate bipartite and accessory bones from carpal fractures or posttraumatic injuries, carpal fusions having to be distinguished from bony ankylosis.

Carpal osteoarthrosis

Despite improved understanding of carpal mechanics, increased awareness of intercarpal ligament injuries, and improved techniques for treating carpal instability, post-traumatic intercarpal osteoarthrosis remains a common problem. Osteoarthritis of the carpal bones, including scapholunate advance collapse wrist, scaphotrapeziotrapezoid arthritis, lunotriquetral arthritis, triquetrohamate arthritis, and pisotriquetral arthritis, follows specific unique patterns, but in each, the final common pathway leads to degenerative change. Injury or deformity leads to instability and altered kinematics, producing abnormal joint contact pressures. Cartilage injury and eventual degeneration of the join follow. The etiology, prevalence, and current evaluation and treatment of these conditions are of importance to hand surgeons.

Acute os styloideum injury in an elite athlete

The os styloideum, an accessory carpal bone, may suffer injury during traumatic wrist flexion. The case described corresponds to an acute os styloideum injury in an elite athlete; a diagnosis made using high-resolution computed tomography and magnetic resonance imaging permitted not only the identification of the anomaly and associated abnormalities but also ruled out more significant injury to the extensor carpi radialis brevis.

Degenerative and post-traumatic arthritis affecting the carpometacarpal joints of the fingers

Symptomatic post-traumatic arthritis affecting the finger CMC joints is less common than might otherwise be expected based on the frequency of injury, especially to the fifth CMC joint. For the fifth CMC joint, the shallow concavoconvex articulation combined with the typical fracture location may provide a protective effect. Non-operative measures are typically successful, except in cases of missed fracture/dislocations and symptomatic joint instability. In these instances, re-construction emphasizes stability first, with an eye toward mobility for the ulnar column. It is common to detect a bony prominence in the region of the dorsal second and third CMC joints during examination of the hand. In most instances, the projection is asymptomatic and likely represents an os styloideum [18]. When painful and unresponsive to nonoperative treatments, this carpometacarpal boss can be excised surgically.

Imaging of wrist masses

The wrist is a complex structure with an extensive differential diagnosis for a presenting mass. However, the vast majority of hand and wrist masses are benign, and many of these have a distinctive radiographic appearance. In this article, the imaging characteristics of the most common entities are reviewed with particular attention to magnetic resonance appearance. The 3 most common hand and wrist lesions include ganglion cysts, giant cell tumors of the tendon sheath, and hemangiomas. Other common lesions that can be diagnosed radiographically include lipomas, neural sheath tumors, infection and inflammation, and variant soft-tissue or bony structures. The appearance of the fibrolipomatous hamartoma will also be demonstrated because this is a radiographically distinctive, though rare, lesion.