Distally based abductor digiti minimi muscle flap

The abductor digiti minimi muscle flap is known as good tissue coverage for the lateral ankle and heel. For reconstruction of the distal portion of the foot, the distally based flap of this muscle can be useful, effectively utilizing the blood supply through the plantar arch communication. A case of frostbite of the right fifth toe is reported, which we successfully repaired with a distally based abductor digiti minimi muscle flap. In addition, some information on distally based use of the muscles of the foot is presented.     

An aberrant flexor digiti minimi brevis manus muscle

During routine anatomical dissection in the right volar wrist region of a 43-year-old female cadaver, we discovered a unique flexor digiti minimi brevis (manus) muscle. The aberrant muscle arose from the medial edge of the flexor carpi radialis tendon and passed obliquely, distally and ulnarward, crossing over the median nerve and then the ulnar artery and nerve at the Guyon canal. The aberrant muscle inserted to the anteromedial surface of the base of the fifth proximal phalanx. The deep branch of the ulnar nerve innervated this muscle. The potential clinical implications of the variant flexor digiti minimi brevis muscle are briefly described.     

Ulnar nerve compression at the wrist by the accessory abductor digiti minimi muscle: wrist trauma as a precipitating factor.

This paper describes four cases of ulnar tunnel compression syndrome caused by the accessory abductor digiti minimi muscle and stresses on the observation that wrist trauma could be an important precipitating factor. Possible pathophysiological explanations of this phenomenon are offered and the anatomy of the accessory abductor digiti minimi muscle is reviewed.     

Variation in insertion of the abductor digiti minimi: an anatomic study

We dissected 70 cadaver hands to examine the anatomy of the insertion of the abductor digiti minimi (ADM). The insertion had 2 forms. In 58 hands the insertion of the ADM was divided into 2 tendinous portions: one attached the base of the proximal phalanx (bone insertion) and the other attached the extensor aponeurosis (extensor insertion). In 12 hands the bone insertion existed solely. The mean length and width of the bone insertion were 10.6 +/- 3.1 and 4.0 +/- 0.9 mm and those of the extensor insertion were 18.5 +/- 4.0 and 2.1 +/- 1.1 mm, respectively. The mean proportion of the width of the extensor insertion to that of whole tendon was 31% (range, 0% to 50%). These observations show greater variation in the insertional anatomy of the ADM than reported previously.     

A modification in technique of abductor digiti minimi (Huber) opponensplasty

Abductor digiti minimi opponensplasty is a well-established method of restoring opposition following median nerve trauma or in congenital deficiency of thenar intrinsic musculature. The abductor digiti minimi is detached distally and rerouted through a subcutaneous tunnel for insertion into the area of the thumb metacarpophalangeal joint. The pivot point for this rotation is the pisiform bone and it is at this site that the ulnar nerve is vulnerable to compression by the transferred muscle. We describe a modification of technique which involves complete islanding of the muscle without re-insertion of its proximal end. This eliminates the possibility of this complication without detracting from the efficacy of opposition produced by the transferred muscle.     

Opponensplasty by abductor digiti minimi for hypoplastic thumb

Surgical Principles Improvement of pinching ability and opposition motion in cases of absence or marked hypoplasia of the thenar muscles. Transposition of the abductor digiti minimi muscle to the thumb in an own modification: lengthening by shifting its origin under careful preservation of blood and nerve supply to the palmaris longus tendon to give better appearance and enough to reach the metacarpophalangeal joint of the thumb and the extensor pollicis longus tendon.     

Abductor digiti minimi opponensplasty in hypoplastic thumb

Ten cases of hypoplastic thumbs were treated by abductor digiti minimi opponensplasty in order to restore opposition of the thumb and reform the wasted thenar eminence. In eight of these ten cases operations were combined with multiple Z-plasty or rotation flap to correct the narrowing of the first web space. Adductor plasty using extensor indicis proprius was performed in six cases to restore the stability of the metacarpophalangeal joint of the thumb and ligament reconstruction of the carpometacarpal joint in one hand. In all cases, the transferred abductor digiti minimi was strong enough to abduct the thumb and provide good functional and cosmetic results. We modified Littler's procedure by transferring the origins of abductor digiti minimi muscle from the flexor carpi ulnaris to the palmaris longus tendon. Our modified method gave a better cosmetic appearance than that provided by Littler's method.     

Modified abductor digiti minimi opponensplasty in congenital hypoplastic thumb with laxity of metacarpophalangeal joint

The abductor digiti minimi (ADM) opponensplasty is used widely as a standard technique of opponensplasty for congenital hypoplastic thumb. Functional results, however, are not always satisfactory in cases of marked laxity of the thumb metacarpophalangeal (MP) joint. The authors have developed a modified procedure of ADM opponensplasty to stabilize the thumb MP joint and to obtain appropriate opponens function. The first step of their modification is to retain the maximum length of transferred ADM muscle. The origin of the ADM is shifted radially and is reattached to the transverse carpal ligament. In our modification the ADM tendon is passed underneath the extensor pollicis longus tendon and is sutured to the adductor pollicis tendon at the ulnar side of the thumb MP joint. By this modified anchoring point the transferred ADM tendon runs across the ulnar side of the thumb MP joint and is expected to act as if it were an ulnar collateral ligament.     

Abductor digiti minimi involvement in Dupuytren's contracture of the small finger

PURPOSE: Dupuytren's contracture (DC) is a common, benign, progressive condition. Patterns of involvement of the ulnar side of the hand, specifically the involvement of the abductor digiti minimi (ADM), have received limited attention; therefore, the purpose of this study was to determine the prevalence, patterns of involvement, and surgical outcomes in DC of the small finger. METHODS: A retrospective review was performed on the hands of all patients who had surgery for DC between January 1998 and March 2002 to determine the incidence of ADM involvement. RESULTS: A total of 149 patients had 195 surgeries on 261 digits during this period. Forty-seven percent of cases involved the small finger and 27% of those involved the ADM. Those cases involving the ADM had statistically significantly greater mean preoperative proximal interphalangeal joint (PIPJ) contracture (53 degrees ) as well as postoperative PIPJ contracture (34 degrees ) when compared with those without ADM involvement of the small finger (31 degrees preoperative PIPJ contracture and 15 degrees postoperative PIPJ contracture, respectively). The most common origin pattern of the ADM involvement was found to arise from both the ADM tendon and overlying fascia (77%). The most common insertion pattern was found to be over the middle phalanx (50%). CONCLUSIONS: We conclude that ADM is involved in DC of the small finger in one quarter of cases. Failure to recognize and resect the diseased cord arising from it and its overlying fascia at the time of surgery may account for the poor outcomes seen in DC of the small finger.     

Isolated contracture of the abductor digiti minimi

A case of isolated contracture of an intrinsic hand muscle, the abductor digiti minimi, after the use of an upper extremity tourniquet is reported. Six cadaver specimens were studied after latex arterial injection. We present an anatomic study and pathomechanical analysis, along with a review of the literature on tourniquet-associated injuries.     

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.     

Abductor digiti minimi musculocutaneous island flap as an opposition transfer: a case report

We described the use of an abductor digiti minimi musculocutaneous (ADM) island flap as an opposition transfer. This procedure is easy and safe, and provides more of a bulge in the thenar area than the Huber transfer. This procedure can be used in the treatment of Blauth grade 2 and 3A hypoplastic thumb.     

The abductor digiti minimi muscle flap: an adjunct in the treatment of metacarpal osteomyelitis

The abductor digiti minimi muscle has a constant 1 to 1.5 cm neurovascular pedicle that arises from the ulnar artery and nerve within Guyon's canal. We have successfully used the abductor digiti minimi as a pedicle transfer as an adjunct in the treatment of chronic osteomyelitis of the small and ring finger metacarpal shafts.     

Innervation pattern of the abductor digiti minimi muscle of the hand

This cadaver study investigated the innervation patterns of the abductor digiti minimi in Guyon's canal. There was only one branch to the abductor digiti minimi in 22 of the 30 specimens. Two branches were found in three hands, and three branches in two. Three other variations were documented.     

Abductor digiti minimi muscle flap after tumor resection in the hand

Extensive resection of aggressive nonmalignant tumors in the hand not only produces large tissue defects but also leaves important vital structures unprotected. The following case of a 25-year-old woman illustrates the successful use of an abductor digiti minimi muscle flap to provide adequate protective coverage.     

Abductor digiti minimi muscle flap in reconstruction of diabetic foot ulcers: A case series

Background

Diabetic foot ulcers (DFUs), a leading cause of amputations, affect 15 % of people with diabetes. Wound coverage in these patients is changelling due to concurrent infection, neuropathy and vascular compromise. Though local muscle flaps were described by Ger et al. and popularized by Attinger et al., these small muscle flaps should be more routinary than they are now.

Methods

A retrospective review of all patients with DFUs with exposed bone and osteomyelitis reconstructed by abductor digiti minimi muscle flaps and free skin grafting between January 2010 and December 2011 was conducted.

Results

This study included eight patients. Six patients had ulcers over the heel and two on the lateral aspect of the forefoot. All flaps survived well with no donor site complications. There was partial loss of skin graft in three cases and infection and total loss in one other case.

Conclusions

Abductor digiti minimi is a safe and reliable flap that provides a durable cover. Level of evidence: Level IV, therapeutic study.     

小趾展肌肌瓣的临床应用

目的探讨小趾展肌肌瓣修复足部偏外侧及足跟部皮肤软组织缺损的手术方法及临床疗效。方法 2002年7月-2010年10月,收治8例足部偏外侧及足跟部皮肤软组织缺损患者。男6例,女2例;年龄28～65岁,平均42岁。左足5例,右足3例。足跟部溃疡2例,跟骨骨折术后切口愈合不良致肌腱、内固定物外露1例,碾挫、挤压伤致足部偏外侧皮肤软组织坏死5例。软组织缺损范围为1.5 cm×1.0 cm～8.0 cm×2.6 cm。病程30 min～26个月。2例细菌培养呈阳性。入院后清创换药9～15 d,待感染控制后采用大小为5.6 cm×1.5 cm～7.6 cm×1.8 cm的小趾展肌肌瓣移位修复创面。供区直接缝合。结果术后7例小趾展肌肌瓣顺利成活;1例术后4 d发生肌瓣部分坏死,对症治疗后肉芽生长良好。供区切口均Ⅰ期愈合。9～21 d肌瓣表面新鲜肉芽生长良好,取小腿内后侧刃厚皮片游离移植修复肌瓣创面。一期皮片游离移植修复肌瓣创面1例,二期修复7例;修复术后皮片均成活,创面Ⅰ期愈合。术后7例获随访,随访时间9～18个月,平均11个月。创面外形、质地和感觉恢复满意。两点辨别觉为16～23 mm,平均19.5 mm。1例足跟部溃疡患者负重行走出现表皮磨损。1例术前腓骨长、短肌腱部分坏死者出现足外翻、肌力下降,其余患者关节功能正常。结论采用小趾展肌肌瓣移位修复足部偏外侧及足跟部皮肤软组织缺损具有手术操作简便,安全可靠,对供区损伤小,不影响负重,创面外形、弹性好,感觉恢复好的优点,疗效满意。     

Distribution pattern of the deep branch of the ulnar nerve in the hypothenar eminence

The deep branch of the ulnar nerve (DBUN) was carefully dissected, using gross and microtechniques, in 21 fresh frozen cadaver upper extremities. This study emphasized branching patterns of the DBUN to the hypothenar muscles and the interrelationship of variations in hypothenar muscle anatomy and DBUN branching patterns. The DBUN generally passed between the abductor digiti minimi and the flexor digiti minimi, and then through the interval between superficial and deep layers of the opponens digiti minimi on its course to the deep palm. Innervation of the hypothenar muscles was by one to four branches of the DBUN. The most common distribution pattern was two major branches, which occurred in 14 (66%) of the specimens. Of these 14 specimens, nine exhibited normal hypothenar muscle anatomy, suggesting a prevalent relationship between three normal muscles and two nerve branches. One main branch occurred in four (19%) specimens, three branches occurred in two (9%) specimens, and four branches occurred in one (4%) specimen. Anatomic variations in the hypothenar muscles were significant, the most notable being the absence of flexor digiti minimi in eight (38%) of the specimens.     

Dupuytren''s disease arising from the abductor digiti minimi

Twenty patients with Dupuytren's disease arising from the abductor digiti minimi have been studied. The different patterns of origin, course, and termination of the diseased cord are described, and the clinical implications discussed.