Extensor Digiti Minimi Tendon Research Articles

Osteochondroma of the Capitate Causing Rupture of the Extensor Digiti Minimi: Case Report

Osteochondromas usually arise from the metaphyses of long bones. Involvement of the carpal bones is extremely rare. We report a case of an osteochondroma originating from the dorsal capitate in a 51-year-old man. Attritional rupture of the extensor digiti minimi tendon resulted from mechanical irritation as it coursed over the mass. Surgical excision of the mass with tendon transfer of the extensor digiti minimi was subsequently performed.

An Assembly of Anomalous Extensor Tendons of the Hand - Anatomical Description and Clinical Relevance.

Innumerable descriptions about variations in the pattern of extensor tendons are recorded in the literature. The dorsum of the hand in an adult male cadaver revealed an unusual pattern of extensor arrangement during a gross anatomical practical session. The extensor digitorum, extensor indicis and extensor digiti minimi tendons displayed a variant pattern. Extensor digitorum contributed tendons only to the middle and ring fingers, with junctura tendinum present between the extensor digitorum for the ring finger and extensor digiti minimi. Interestingly, an accessory muscle was observed arising from the common extensor origin passing to the index finger, in addition to the usual extensor indicis. The origin and insertion of extensor digiti minimi was as usual with an accessory slip contributed from the extensor carpi ulnaris to the proximal phalanx of the fifth finger. The plethora of variations in this region is of paramount importance for the reconstructive surgeon, who may utilize the accessory tendons to restore functional capacity of the fingers.

The anatomical variations of the extensor tendons to the dorsum of the hand

To lead a quality life, tendon repair must be performed in a trauma causing damage to the extensor tendon of the hand. The aim of this study is to study the structures that can be used as donor tendons. Fifty-four dissected adult hands were examined to study the pattern of the extensor tendons on the dorsum of the hand. The most common distribution patterns of the extensor tendons of the fingers were as follows: a single extensor indicis proprius (EIP) tendon which inserted ulnar to the extensor digitorum (ED)-index; a single ED-index; a single ED-middle; a single ED-ring; an absent ED-little; a double extensor digiti minimi (EDM), and a single ED-ring to the little finger. The frequency of the number of tendons is as follows: a single (87.03%) EIP, a single ED-index (100%), a single (92.6%) ED-middle, a single (75.9%) ED-ring, and an absent (68.5%) or a single (24.1%) ED-little. A double (88.9%) EDM tendons were seen. The thickest type of juncturae tendinum (JT) is found primarily between the ring and little fingers (90%). Suitable excessive tendon and the thickest JT as donor tendon were found in the fourth intermetacarpal space. The present findings, especially the fourth intermetacarpal space, may explain why incisions on the dorsum of the hand should be large and performed with particular care. It is necessary to have a thorough understanding of the arrangements of the multiple extensor muscles and their junctural connections of the hand when tenoplasty or tendon transfer is required.

Anatomic variation of the 5th extensor tendon compartment and extensor digiti minimi tendon

Anatomic variation within the 5th extensor compartment may contribute to the development of tenosynovitis and limit the usefulness of the extensor digiti minimi (EDM) for tendon transfer. The purpose of this study was to assess the anatomic variation of the EDM tendon and its surrounding retinaculum, with particular attention to anatomical variation between specimens. Forty-one fresh cadaver hands were dissected. The length of the 5th compartment retinaculum was noted. The incidence of an intercompartmental septum was noted in each specimen as well as the type of tendinous attachments present between the EDM and extensor digitorum communis (EDC) tendons. The presence and length of any accessory retinacular bands distal to the edge of proper extensor retinaculum was also noted. Only one specimen contained a single EDM tendon, while 71% (n = 29) of specimens contained two slips and 23% (n = 9) had three slips; 24% (n = 10) of EDC tendons had no slip to the small finger, while 61% (n = 25) of specimens had a single slip to the small finger. The EDC's contribution to the small finger was found to be an independent tendon in 42% of cases (n = 17), while 34% (n = 14) of specimens were found to have a common EDC slip, which branched to both the ring and small finger. Three EDM tendons divided distal to the extensor retinaculum, while the remaining EDM tendons divided beneath or proximal to the extensor retinaculum. Seventy-three percent (n = 30) of the specimens had an accessory retinacular band surrounding the EDM tendon identified at the base of the 5th metacarpal. Eighty-eight percent (n = 36) of hands had a septum between the EDM slips. The surgeon should be aware of variability within the 5th dorsal compartment in cases of trauma and in cases of tendon transfer. In our series 30 of 41 specimens were noted to contain an accessory dorsal retinacular band surrounding the EDM and 36 specimens were noted to contain a septum within the 5th compartment. The presence of an accessory retinacular band surrounding the EDM at the level of the 5th metacarpal base is an anatomic finding that requires further investigation.

Injection sous-cutanée de mercure et rupture de tendon extenseur par un thermomètre cassé

A 28-year old medical doctor presented with a hand injury caused by a broken mercury thermometer .The extensor digiti minimi tendon was ruptured. Operative treatment included debridement and removal of the mercury followed by repair of the tendon. Reoperation was required to excise wound granulomatous reaction from residual droplets of mercury. There were no signs and symptoms of mercury intoxication. To prevent mercury intoxication after subcutaneous metallic mercury injection, complete surgical removal of the mercury and serial monitoring of blood and urine mercury concentrations is mandatory.

Effect of wrist and ulna head position on gliding resistance of the extensor digitorum minimi and extensor digitorum communis III tendons: A cadaver study

While attrition from sharp bony surfaces is the most common cause of extensor digiti minimi (EDM) tendon rupture, the etiology of other cases of spontaneous EDM tendon rupture is still unknown. Friction within the compartment may play a role, especially with ulna dislocation. The purpose of this study was to compare gliding resistance of the EDM tendon with that of a tendon which rarely ruptures spontaneously, the extensor digitorum communis of the middle finger (EDC III) tendon, under various wrist and ulna head positions. Eight fresh frozen cadavers were used. Gliding resistance between the tendon and its sheath in each compartment was measured in five different wrist positions and three different ulna head positions. Gliding resistance of the EDM tendon (0.13 +/- 0.03 N) was significantly greater than the EDC III tendon (0.09 +/- 0.03 N) (p < 0.05). For the EDM tendon, the gliding resistance in ulnar deviation or pronation was higher than the gliding resistance in neutral, radial deviation, or supination (p < 0.05), and the gliding resistance with ulnar lengthening (over 6 mm) or dorsal ulnar dislocation (over 9 mm) was higher than in neutral ulnar head positioning. For the EDC III tendon, the gliding resistance in ulnar deviation was significantly higher than the gliding resistance in neutral, radial deviation, or supination, or dorsal dislocation with ulnar lengthening (p < 0.05). Wrist ulnar deviation, ulnar dorsal dislocation (over 9 mm), and ulnar lengthening (over 6 mm) increased the gliding resistance of the EDM tendon. In patients at risk for EDM rupture, such as those with rheumatoid arthritis or distal radioulnar joint osteoarthritis, avoiding such positions may be advantageous.

An anatomic study of the extensor tendons of the human hand.

A total of 548 upper limbs (276 right and 272 left hands) from Japanese cadavers were dissected. The arrangements of extensor indicis proprius, extensor digitorum communis (EDC), and extensor digiti minimi tendons and the intertendinous connections were studied. The most common pattern of extensor tendons was as follows: the index finger had a single EDC tendon, the middle finger had a single EDC tendon, the ring finger had a single EDC tendon, and the small finger had a single EDC tendon or a single common EDC tendon distributed to the ring and small finger. A single extensor indicis proprius tendon ran along the ulnar side of the EDC, and the extensor digiti minimi tendon consisted of 2 slips. Intertendinous connections were classified into 3 types: type 1 with a filamentous band, type 2 with a fibrous band, and type 3 with a tendinous band subdivided to r-shaped and y-shaped. The most common patterns were type 1 in the second intermetacarpal space (IMCS), type 3r in the third IMCS, and type 3y in the fourth IMCS.

Extensor digiti minimi tendon «rerouting transfer in permanent abduction of the little finger

Permanent abduction of the little finger is a bothersome deformity which usually occurs in the context of sequelae of ulnar nerve palsy (Wartenberg's sign), but also in rheumatoid arthritis. The authors report an original technique for correction of this deformity. The extensor digiti minimi tendon is sectioned at its distal insertion and transferred in the wrist through the extensor retinaculum. The "rerouted" tendon is finally resutured distally on the radial aspect of the interosseous muscle. Side-to-side suture of the transferred tendon to the extensor digitorum tendon of the little finger further reinforces the solidity of the procedure. The distal insertion of the extensor digiti minimi tendon is consequently radialized. Its new direction eliminates the abduction component, and the tendon then behaves as an active adductor of the little finger. Five cases (2 cases of ulnar nerve palsy, 3 cases of rheumatoid arthritis) are reported with a mean follow-up of 19 months. All patients have complete active adduction of the little finger in extension, with a persistent capacity for abduction. The other correction techniques published in the literature are discussed.

The extensor tendons to the little finger: An anatomic study

Fifty cadaver hands were dissected to better delineate the extensor tendon anatomy to the little finger. The extensor digitorum communis was present in 35. Of 15 hands without an extensor digitorum communis, 12 had a junctura present. Three hands lacked both extensor digitorum communis and juncturae. Transfer of the extensor digiti minimi tendon in these hands could cause loss of extension to the little finger. Ten hands had a direct attachment of the extensor digiti minimi tendon on the abductor tubercle. Twenty-two hands had either an attachment of the extensor digiti minimi on the abductor tubercle, an unbalanced ulnar slip of the extensor digiti minimi, or both, anatomic factors that could--in the event of ulnar nerve compression or laceration--cause Wartenberg's sign. Twenty-eight hands did not have an anatomic variant of the extensor that could cause ulnar deviation of the little finger.

Extensor Digiti Minimi Tendon Transfer to Prevent Recurrent Ulnar Drift

Thirty percent of patients with rheumatoid arthritis develop ulnar drift. Although numerous operations have been described, recurrence of the deformity is frequent. We recommend use of the extensor digiti minimi tendon transfer to prevent recurrent ulnar deviation. The tendon insertion is moved from a dorsal location to a dorsal-radial position. In this new location, the tendon produces both extension and radial deviation. Moreover, this transfer is maximally effective in extension when ulnar drift is greatest. We have used this transfer 28 times during the past 6 years. In evaluating patients more than 1 year after surgery, metacarpal phalangeal joint extension averaged 52 degrees and there was no evidence of recurrent ulnar drift of the little finger. The only problem was slight hyperextension of less than 5 degrees in approximately half of the patients. However, in no patient was this functionally a problem. We recommend the use of this tendon transfer in all patients with ulnar drift undergoing metacarpal phalangeal joint replacement for rheumatoid arthritis.

Extensor digiti minimi tendon transfer to correct abducted small finger in ulnar dysfunction

A tendon transfer to correct the abducted posture of the small finger in patients with ulnar nerve dysfunction is described. The extensor digiti minimi is transferred deep to the extensor digitorum communis tendon or junctura tendinae to the small finger and inserted into the radial portion of the extensor hood, correcting the muscle imbalance. Successful results in 10 patients are reported.

Extensor tendon involvement in Smith's and Galeazzi's fractures

Extensor tendon involvement in three Smith's and two Galeazzi's fractures are reported. In two cases of previous Smith's fracture, the extensor indicis proprius tendon had been entrapped and ruptured in one case, and in the other the extensor digitorum communis tendon of the index was pierced by the fragment. Both showed a severe tenodesis effect on the index finger and thumb. In a new case of Smith's fracture, long extensor tendons of the fingers and thumb had been trapped beneath a dorsally displaced third fragment making closed reduction impossible. In the two cases of Galeazzi's fracture; in one the extensor carpi ulnaris tendon was trapped between the dorsally displaced ulnar head and the avulsed styloid process and in the other, the extensor digiti minimi tendon was caught beneath the radial border of the dorsally dislocated ulnar head.

The abducted little finger in low ulnar nerve palsy

In 12 dissections the extensor digiti minimi tendons inserted into the abductor tubercle of the proximal phalanx. In eight of the 12, the tendons passed to the ulnar side of the abductor-adductor axis of the metacarpophalangeal joint. A separate tendon from the extensor digitorum communis to the little finger was found in only one dissection, with all others showing a connecting band which varies in its obliquity and thus in its adducting effect. To correct an abducted little finger, the ulnar portion of the extensor digiti minimi was transferred to the radial side of the little finger. Two methods were used: (1) the tendon was passed to the volar side of the metacarpophalangeal joint, if the joint could be hyperextended; if not, (2) a simple transfer to the radial collateral ligament was performed.