BACKGROUND: To understand considerable variations in number of adult extensor ten-dons at the dorsal side of the wrist and hand.
METHODS: We examined histological sections from 30 human fetuses of gestational age 7-39 weeks and crown-rump length 22-323 mm.
RESULTS: At the carpal level, earlier or smaller fetuses showed a simpler configuration with fewer tendon slips, whereas later or larger fetuses had a greater number of tendon slips with considerable variations in number and topographical relationships. Tendon slips of the early extensor digitorum to the middle and ring fingers were always 1 or 2, but were seven or more at late term. A tendon of the extensor digitorum to the little fin-ger could not be distinguished from other tendons at the carpal bone level. At the meta-carpal bone level, however, it extended from the ring finger tendon toward two slips of the extensor digiti minimi tendon. At the distal carpal level at midterm and late term, in which the tendon sheath was lost, each of the extensor digitorum tendon slips further divided to provide a mediolateral linear cluster of thin bundles. This large number of tendon components joined and united together to provide a single tight tendon at the level of the metacarpophalangeal joints. The extensor pollicis longs tendon usually lost a membranous septation when it crossed the extensor carpi radialis brevis tendon.
CONCLUSIONS: Tendon slips in the fourth and fifth canals of the sheath were most likely to reduce in number after birth depending on the mechanical demand.

BACKGROUND: Due to its ability to provide stable fixation and permit early mobilization, volar plating has become the recommended technique for the surgical stabilization of distal radius fractures. The extensor pollicis longus (EPL) tendon may be injured or ruptured as a result of undetected screw penetration or drill plunging. During surgery, it is critical to detect any potential screw penetration so that it can be corrected.
METHODS: A 32-year-old woman presented six weeks post-distal radius plating with an inability to extend her left thumb. Clinical examination revealed loss of extension at the interphalangeal joint, stiff wrist, tender point over the dorsal aspect of the wrist, and an intact sensory nerve function.
CONCLUSIONS: Dynamic ultrasound and magnetic resonance imaging (MRI) both revealed no evidence of tendon rupture or EPL tendon movement. X-rays revealed the distal epiphyseal screws penetrating the far cortex. Intraoperatively, the EPL tendon was found to be impinged by a screw. The tendon was released, tenolysis was performed, and the distal screws were shortened.
CONCLUSIONS: In order to assess screw penetration into the far cortex, volar plating for distal radius fractures should be performed using intraoperative imaging views such as lateral, 45-degree supination, 45-degree pronation, dorsal tangential, and skyline views. Timely interventions after distal radius fracture fixation preserve tendon function, and early detection of tendon compromise is essential to preventing additional damage.

UNASSIGNED: This research sought to analyze a cohort of patients with extensor pollicis longus (EPL) ruptures after volar locked plating of a distal radius fracture (DRF) to characterize the incidence of ruptures that are unlikely to be related to dorsal screw prominence.
UNASSIGNED: This is a retrospective, observational, descriptive cohort study of adults with operative fixation of a closed DRF and an EPL rupture between 2002 and 2022. Eighteen patients with operative fixation using a volar plate of a closed DRF had an EPL rupture. The cohort consisted of 66% women with an average age of 57.5 years. Median follow-up was 14.5 months.
UNASSIGNED: The incidence of EPL rupture was 0.4% (18/4768). The average time from DRF and DRF fixation to EPL rupture was 3.7 and 3.4 months, respectively. Based on the operative record, in 2 of the 18 patients (11%), the rupture was directly attributable to prominent hardware; however, in 4 of the 18 patients (22%), the rupture was not related to prominent hardware, and the cause was indeterminate in 12 patients (67%). Radiologic analysis of those in the indeterminate group demonstrated that 5 of the 12 patients had screws that had a high probability of being prominent.
UNASSIGNED: The incidence of EPL rupture after volar plating of DRF is between 0% and 1% and usually occurs about 3 months after fixation. Approximately 50% of EPL ruptures are attributable to prominent dorsal screws. Although screw prominence is an important cause of EPL rupture, it is not the sole cause of rupture.

Despite several reports on the running of the extensor pollicis brevis (EPB) tendons, the classification of tendon insertions remains ununified due to differences in reports. This diversity in tendon patterning is attributed to the process of tendon development. In this study, we assessed the running of the EPB tendons of 44 cadaver hands fixed in ethanol/formalin in detail and examined the existing classification method. The specimens were obtained from 15 women and seven men, with an average age of 86 years. Consistent with previous reports, we observed a wide diversity in the running of the EPB tendons. Further, we found that EPB tendon insertions showed diverse variations in the proportion and running of fibers, making it difficult to classify them into independent patterns. It is speculated that the EPB tendon develops through a different process than that of the muscle body of the EPB and that the entire muscle-tendon module of the EPB is evolving. The diversity of the EPB tendons observed in this study may reflect the ongoing process of evolution. In clinical practice, a wide variation in the running of the EPB tendons should be considered.

UNASSIGNED: IV.

UNASSIGNED: Rupture of the extensor tendons secondary to fractures involving the distal radius is a well-recognized rare complication. In patients with implants particularly, there exists a tendency for attributing the implant as a cause for the tendon rupture. We retrospectively studied the patients with extensor tendon injuries related to distal radius fractures, analyzed the factors leading to the rupture, suggest few preventive measures and describe the management strategy of these ruptures.
UNASSIGNED: 21 patients who were treated for extensor tendon rupture following distal radius fractures in the period of 2014-2022 were retrospectively analyzed. 19 patients had been managed with surgery and two patients conservatively for the distal radius fracture. The time interval between the fracture fixation and tendon rupture, the time interval between tendon rupture and presentation, the extensor tendons injured and the position of the impinging screws or bony spur in relation to the extensor compartments, necessity for implant removal and modality of tendon reconstruction were studied in these patients.
UNASSIGNED: Extensor pollicis longus was found to be ruptured in all the patients except one patient with Extensor indicis proprius rupture alone. The time interval between the fracture fixation and tendon rupture averaged at 32.5 months. End to end repair of the ruptured tendons was never possible even in patients who presented earlier. 10 patients underwent intertendinous bridge grafting and 11 patients underwent tendon transfer. All the patients achieved full extension of thumb with no donor deficit.
UNASSIGNED: Distal radius fracture related extensor tendon injuries pose a technical challenge to the surgeon and concern to the patient in the form of recurring surgeries. However, with immediate presentation to the surgeon and their use of appropriately designed management algorithm, these patients could be immensely satisfied with the outcome.

BACKGROUND: the rupture of the extensor pollicis longus (EPL) tendon is a rare pathology and usually occurs in adult women in relation to distal radius fractures.
METHODS: we present the case of an adolescent female patient who, after conservative treatment with splinting of a Peterson type I physeal fracture of the radius, suffered an acute extension deficit of the thumb at six weeks, diagnosed with clinical radiological examination as spontaneous rupture of the extensor pollicis longus (EPL). She was treated with extensor pollicis indicis propius (EIP) transfer with satisfactory results and recovering her usual activity one month after surgery.
CONCLUSIONS: this kind of injuries are infrequent in pediatric ages and rarely described in a pediatric patient with immature skeleton, what makes this case something exceptional. It is necessary considering these complications in patients of low ages even with no other risk factors. The most frequent treatment applied in adults as in children is the EIP transference with good results in the long term.
UNASSIGNED: la rotura del tendón extensor pollicis longus (EPL) constituye una patología infrecuente y se presenta normalmente en mujeres adultas en relación con fracturas de radio distal.
UNASSIGNED: se presenta el caso de una paciente adolescente femenino que, tras tratamiento conservador con férula de una fractura fisaria Peterson tipo I en radio, sufre a las seis semanas déficit agudo de extensión del pulgar, diagnosticada mediante examen clínico radiológico de rotura espontánea del extensor pollicis longus. Es tratada por medio de transferencia del extensor propio del índice (EPI) con resultados satisfactorios y recuperación de su actividad habitual al mes postoperatorio.
UNASSIGNED: este tipo de lesiones son poco frecuentes en edad pediátrica y casi nunca descritas en un paciente pediátrico con inmadurez esquelética, lo cual hace de este caso algo excepcional. Es necesario tener en cuenta este tipo de complicaciones en pacientes de baja edad aún sin otros factores de riesgo asociados. El tratamiento aplicado más frecuentemente, tanto en adultos como en niños, es la transferencia del extensor propio del índice con buenos resultados a largo plazo.

A spontaneous rupture of the extensor pollicis longus (EPL) tendon after a fracture of the distal radius is a known complication in adults. In contrast, there are a paucity of reports concerning EPL tendon ruptures in children and adolescents. The authors present a case of a spontaneous rupture of the EPL tendon in a 15-year-old girl after a non-displaced distal radius fracture. The patient had no predisposing factors including rheumatoid arthritis or steroid injection. During surgery, the EPL tendon was found to be ruptured at the extensor retinaculum (third compartment). Extensor indicis proprius (EIP) to EPL transfer was performed. At the 18-month follow-up, the patient was asymptomatic and showed satisfactory thumb function, with normal active extension.
La rotura espontánea del tendón del extensor largo del pulgar (EPL) tras una fractura distal del radio es una complicación conocida en adultos. En cambio, son escasos los informes sobre roturas del tendón del EPL en niños y adolescentes. Los autores presentan un caso de rotura espontánea del tendón del EPL en una niña de 15 años tras una fractura distal del radio no desplazada. La paciente no presentaba factores predisponentes como artritis reumatoide o inyección de esteroides. Durante la intervención quirúrgica, se descubrió que el tendón del EPL estaba roto a la altura del retináculo extensor (tercer compartimento). Se realizó una transferencia del extensor indicis proprius (EIP) al EPL. A los 18 meses de seguimiento, el paciente estaba asintomático y mostraba una función satisfactoria del pulgar, con una extensión activa normal.

OBJECTIVE: Variations of the extensor pollicis longus are rare. When present, these include a separate extensor pollicis longus muscle, tendon or an intertendinous connection with nearby tendons within the deep extensor compartment of the forearm. Here, we report an extremely rare variation of an accessory extensor pollicis longus originating from the extensor digitorum.
METHODS: An unusual muscle was found during the routine dissection forearm of a 71 year-old at death male cadaver.
RESULTS: This variant muscle originated from part of the extensor digitorum muscle belly that supplies the index finger. It became tendinous and entered the third extensor compartment of the wrist before joining the ulnar side of the extensor pollicis longus tendon. Traction on the muscle belly resulted in simultaneous extension of both the thumb and the index finger.
CONCLUSIONS: This study documents an extremely rare extensor tendon to the thumb originating from the extensor digitorum, with a unique attachment to the normal extensor pollicis tendon. There have been minimal accounts of this variation, and the present report adds to the limited literature. Furthermore, the report suggests a new subtype, 1f, be included in the existing classification system. Surgeons should be aware of this rare variant for proper evaluation, diagnosis and surgical treatment. Further anatomical studies are needed to study the prevalence of this variant.

Anomalous variants of the extensor tendons in the first and third compartments of the wrist have been described following cadaveric study. Being aware of such variants during either an elective or emergency hand surgery will prove beneficial in the execution of the extensor tendon repairs. A very few clinical reports are available in the literature. We report a rare finding of extensor pollicis brevis tendon accompanying the solitary extensor pollicis longus tendon in the third compartment observed during an emergency trauma surgery.Level of evidence V.