Biomechanical Analysis of Palmar Midcarpal Instability and Treatment by Partial Wrist Arthrodesis.

PURPOSE: To create a biomechanical model of palmar midcarpal instability by selective ligament sectioning and to analyze treatment by simulated partial wrist arthrodesis. METHODS: Nine fresh-frozen cadaver arms were moved through 3 servohydraulic actuated motions and 2 passive wrist mobilizations. The dorsal radiocarpal, triquetrohamate, scaphocapitate, and scaphotrapeziotrapezoid ligaments were sectioned to replicate palmar midcarpal instability. Kinematic data for the scaphoid, lunate, and triquetrum were recorded before and after ligament sectioning and again after simulated triquetrohamate arthrodesis (TqHA) and radiolunate arthrodesis (RLA). RESULTS: Following ligament sectioning, the model we created for palmar midcarpal instability was characterized by significant increases in (1) lunate angular velocity, (2) lunate flexion-extension, and (3) dorsal/volar motion of the capitate during dorsal/volar mobilizations. Simulated TqHA caused significantly more scaphoid flexion and less extension during the wrist radioulnar deviation motion. It also increased the amount of lunate and triquetral extension during wrist flexion-extension. Simulated RLA significantly reduced scaphoid flexion during both wrist radioulnar deviation and flexion-extension. CONCLUSIONS: Both simulated arthrodeses eliminate wrist clunking and may be of value in treating palmar midcarpal instability. However, simulated RLA reduces proximal row motion whereas simulated TqHA alters how the proximal row moves. Long-term clinical studies are needed to determine if these changes are detrimental. CLINICAL RELEVANCE: Palmar midcarpal instability is poorly understood, with most treatments based on pathomechanical assumptions. This study provides information that clinicians can use to design better treatment strategies for this unsolved condition.

Triquetrohamate Impaction Syndrome: An Unrecognized Cause of Ulnar-Sided Wrist Pain; Its Presentation Further Defined.

BACKGROUND: The aim of this review was to further define the clinical condition triquetrohamate (TH) impaction syndrome (THIS), an entity underreported and missed often. Its presentation, physical findings, and treatment are presented. METHODS: Between 2009 and 2014, 18 patients were diagnosed with THIS. The age, sex, hand involved, activity responsible for symptoms, and defining characteristics were recorded. The physical findings, along with ancillary studies, were reviewed. Delay in diagnosis and misdiagnoses were assessed. Treatment, either conservative or surgical, is presented. Follow-up outcomes are presented. RESULTS: There were 15 male and 3 females, average age of 42 years. Two-handed sports such as golf and baseball accounted for more than 60% of the cases, and these cases were the only ones that involved the lead nondominant hand, pain predominantly at impact. Delay in diagnosis averaged greater than 7 months, with triangular fibrocartilage (TFCC) and extensor carpi ulnaris (ECU) accounting for more than 50% of misdiagnoses. Physical findings of note included pain over the TH joint, worse with passive dorsiflexion and ulnar deviation. Radiographic findings are described. Instillation of lidocaine with the wrist in radial deviation under fluoroscopic imaging with relief of pain helped to confirm the diagnosis. Conservative treatment was successful in 9 of 18 patients (50%), whereas in the remaining, surgical intervention allowed approximately 80% return to full activities without limitation. CONCLUSION: Triquetrohamate impaction syndrome remains an underreported and often unrecognized cause of ulnar-sided wrist pain. In this report, the largest series to date, its presentation, defining characteristics, and treatment options are further elucidated.

The anatomical site of constriction of the median nerve in patients with severe idiopathic carpal tunnel syndrome.

During open carpal tunnel release in patients with severe idiopathic carpal tunnel syndrome, an area of constriction in the substance of the median nerve is frequently noted. In a prospective study of 30 patients, the central point of the constricted part of the nerve was determined intraoperatively and found to be, on average, 2.5 (range 2.2-2.8)cm from the distal wrist crease. This point always corresponded to the location of the hook of the hamate bone. These intraoperative findings were compared with the "narrowest" point of the carpal canal as determined by anatomical and radiological studies in the literature.

Multiple carpometacarpal dislocations and an associated fracture of the hamate: an uncommon injury.

Dislocation of the four ulnar carpometacarpal (CMC) joints with a concurrent fracture of the hamate is a rare injury, with a paucity of published cases. A great force is required to dislocate a CMC joint. Diagnosis can easily be missed, due to other serious associated injuries. Appropriate treatment of CMC joint dislocations usually leads to excellent outcomes. We present a case of dorsal dislocation of the four ulnar CMC joints after punching a wall. The injury was treated with a closed reduction and percutaneous transfixation with Kirschner-wires. Despite the extensive injury, the functional result was good (full and painless range of motion) at 12 weeks of follow-up.

Surgical excision of ununited hook of hamate fractures via the carpal tunnel approach.

INTRODUCTION: Direct excision of a symptomatic ununited hook of hamate fracture is the gold standard, most frequently via a Guyon space approach. The open carpal tunnel approach is another option, which has not previously been commonly considered and not reported in a peer review journal. Our study aims to highlight the carpal tunnel approach as a successful technique in a consecutive series of ununited hook of hamate fractures. PATIENTS AND METHODS: Seven patients (all male and mean age 30.7 years) were reviewed with symptomatic ununited fractures following a period of cast immobilization. All the patients operated on underwent excision of the hook of hamate fragment via the open carpal tunnel approach. RESULTS: All patients successfully returned to their pre-injury level of functioning after 8-12 weeks and there were no complications. CONCLUSIONS: Our study highlights the open carpal tunnel approach as a successful technique for open excision of symptomatic ununited hook of hamate fractures, because of its familiarity, ease of performance, excellent visualization and low morbidity. Level of Evidence IV Case Series.

Osteoblastoma del hueso ganchoso / Hamatum osteoblastom

El osteoblastoma es un tumor óseo primario poco frecuente. Su presentación en la extremidad superior y más específicamente en los huesos carpianos es inusual. Se presenta un caso de osteoblastoma localizado en el hueso ganchoso y ser revisa el tratamiento realizado en esta infrecuente localización. Paciente varón joven con dolor y tumefacción en el dorso de la mano de un año de evolución, refractario al tratamiento médico. Las pruebas complementarias mostraron una tumoración lítica en el hueso ganchoso con características no agresivas. Fue tratado mediante curetaje y relleno con injerto autólogo de cresta ilíaca. El estudio de anatomía patológica diagnosticó que se trataba de un osteoblastoma. El resultado fue satisfactorio, con desaparición total del dolor e imagen radiológica de restitución completa del defecto óseo, sin signos de recidiva a los 4 años. El tratamiento debe ser el curetaje más injerto autólogo. En cambio, en los casos con datos agresivos se puede plantear la resección del hueso afectado (AU)

Osteoblastoma is an infrequent primary osseous tumour. Its presentation in the upper extremities and more specifically in the carpal bones is unusual. We present a case of osteoblastoma localized in the hamate bone and review the treatment realized in this infrequent localization. A young male patient with pain and swelling in the back of his hand of one year's evolution, resistant to medical treatment. Complementary tests showed lytic tumefaction in the hamate bone with non-aggressive characteristics. It was treated by curettage and filling the iliac crest with autologous graft. The pathological anatomical study diagnosed that it was a case of osteoblastoma. The result was satisfactory, with total disappearance of the pain and a radiological image of complete restitution of the osseous defect, with no signs of recurrence after 4 years. The treatment should be curettage plus autologous graft. Conversely, resection of the affected bone can be considered in cases with aggressive data (AU)

Fracturas del ganchoso / Hamate fractures

Objetivo. El objeto de este trabajo es presentar nuestra experiencia en el tratamiento de las fracturas del ganchoso y hacer una revisión bibliográfica. Material y método. Hemos revisado de forma retrospectiva 10 pacientes tratados en nuestro centro entre 2005-2012 que presentaban fractura del ganchoso. Seis casos eran fracturas del cuerpo y 4 fracturas del gancho. Cinco presentan otras lesiones asociadas. El retraso diagnóstico osciló entre los 30 días y los 2 años. El tiempo de seguimiento oscilaba entre 1 y 9 años. Se valoró la calidad de vida del paciente con el cuestionario DASH. Cinco pacientes con fractura del cuerpo fueron intervenidos y uno fue tratado conservadoramente. Dos pacientes con fractura del gancho fueron tratados con inmovilización y otros dos tratados con exéresis del fragmento. Resultados. La fuerza de prensión y de la pinza digital estaba disminuida en 2 casos. La flexoextensión de la muñeca estaba limitada en 3 casos. La movilidad de los dedos era normal en todos los casos excepto en uno. La puntuación obtenida en el DASH estaba en los límites de la normalidad en todos los casos excepto en un caso de fractura del gancho y en 2 casos de fractura del cuerpo. Conclusiones. El tratamiento quirúrgico deberá reducir la luxación y estabilizar las lesiones con osteosíntesis. Las fracturas del gancho suelen diagnosticarse tardíamente y su tratamiento más aconsejable es la exéresis, aunque no es deducible de este estudio (AU)

Objective. The purpose of this paper is to present our experience in the treatment of the fractures of the hamate and to make a review of the literature on this topic. Material and method. We retrospectively reviewed 10 patients treated in our clinic between 2005-2012 suffering from fractures of the hamate. Six cases were fractures of the body and four were fractures of the hamate. Five cases were of associated injuries. Diagnostic delay ranged from 30 days to 2 years. Patient follow-up ranged from 1 to 10 years. Patient satisfaction was evaluated using the DASH questionnaire. Five patients with a fracture of the body underwent surgery, and one was treated conservatively. Two patients with fracture of the hook of the hamate were treated with immobilization, and two more patients had the fragment removed. Results. The grip strength and the digital clip were reduced in 2 cases. Flexion and extension of the wrist was limited in 3 cases. The mobility of the fingers was normal in all the cases, except in one. The results obtained from the DASH questionnaire were normal in all the cases, except in one case of fracture of the hamate, and in two cases of fracture of the body. Conclusions. The surgical treatment should reduce the dislocation and stabilize the injuries with osteosynthesis. The fractures of the hamate are usually diagnosed late, and the most recommended treatment is removal of the fragment, although it cannot be deduced from this study (AU)