(A) an arteriovenous malformation
(B) a capillary malformation
(C) a hemangioma
(D) a lymphatic malformation
(E) a venous malformation

The correct response is Option B.

This 40-year-old man has a capillary malformation, or port-wine stain. These lesions are often seen in the distribution of the abducens (VI) and facial (VII) nerves. If left untreated, cobblestoning and progressive darkening may occur due to ectasia of the vessels within the capillary malformation.

An arteriovenous malformation is a high-flow lesion often characterized by a palpable thrill or bruit. Compression of the lesion results in occlusion of the associated arteriovenous fistula, causing a baroreceptor response and an increase in blood pressure. This leads to a decrease in heart rate and is known as the Branham sign.

Hemangiomas are vascular tumors that appear just after birth and rapidly enlarge during the first year of life. Because spontaneous regression is common, conservative management is suggested for non-life-threatening lesions that do not obstruct the airway or visual axis.

Lymphatic malformations, also known as cystic hygromas, occur most frequently in the head and neck region and often enlarge in response to an adjacent infection. Recurrent swelling can lead to scarring, which will significantly decrease the size of the lesion.

Venous malformations are low-flow lesions composed of dilated venous channels. These lesions are compressible and have a propensity to fill with blood when the patient changes body positions. When the malformation is associated with thrombosis, pain may result.

References
1. Jackson IT, Carreno R, Potparic Z, et al. Hemangiomas, vascular malformations, and lymphovenous malformations: classification and methods of treatment. Plast Reconstr Surg. 1993;91:1216.
2. Kohout MP, Hansen M, Pribaz JJ, et al. Arteriovenous malformations of the head and neck: natural history and management. Plast Reconstr Surg. 1998;102:643.
3. Mueller BU, Mulliken JB. The infant with a vascular tumor. Semin Perinatol. 1999;23:332.

PHOTO

A 25-year-old man sustains a complete transverse laceration of the extensor pollicis longus tendon of the dominant right thumb. The tendon is surgically repaired and the hand is splinted; occupational therapy is started three weeks later. Two months after surgery, the patient has pain, slight swelling, and discoloration at the level of the interphalangeal joint; a photograph and MRI are shown above.

Which of the following is the most appropriate next step in management?

(A) Decortication
(B) Neurectomy
(C) Neuroplasty
(D) Tendon repair
(E) Tenolysis

PHOTO

The correct response is Option A.

Patients who have pain disproportionate to the level of injury should be evaluated to exclude a potential diagnosis of osteomyelitis, which in those without open fractures can result from local infection or hematogenous spread. In this patient, the MRI shows an abnormal signal in the proximal phalanx, which is consistent with osteomyelitis. Indium-111-labeled leukocyte scanning can also be used to confirm the diagnosis. Although Staphylococcus aureus is the most likely causal organism, Mycobacterium marinum and anaerobic organisms can also be associated. In cases such as this one, appropriate management includes surgical exploration, decortication to decompress the infected bone, and removal of all involved bone. Antibiotics should be administered intravenously following this procedure, and bone grafting should be performed at a later date. Photographs of the decortication procedure are shown above.

Neurectomy is used for repair of neuromas, which manifest as a localized positive Tinel's sign, while neuroplasty would be the procedure of choice in a patient who has an entrapped nerve. Tendon repair is not required because the previous repair is still intact, as shown in the photograph and MRI. Tenolysis will improve the limited tendon excursion seen in patients who have tendon adhesions or scarring.

References
1. Gilula LA. The Traumatized Hand and Wrist: Radiographic and Anatomic Correlation. Philadelphia, Pa: WB Saunders Co; 1992.
2. Neviaser RJ. Acute infections. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;1:1033-1047.

A 30-year-old man is undergoing evaluation one week after sustaining a sharp laceration over the dorsal metacarpophalangeal (MP) joint of the thumb from a razor knife. At the time of injury, the wound was cleansed in the emergency department and primary closure was performed. On current physical examination, he cannot extend the interphalangeal joint of the thumb.

Which of the following is the most appropriate management?

(A) Control of edema
(B) Removal of the sutures
(C) Sensory re-education of the thumb
(D) Repair of the extensor pollicis longus tendon
(E) Arthrodesis of the MP joint

The correct response is Option D.

In this patient who has a functional deficit involving the interphalangeal (IP) joint of the thumb after sustaining a zone V laceration of the extensor pollicis longus (EPL) tendon, repair of the tendon will provide the best functional outcome. The EPL tendon facilitates hyperextension of the IP joint of the thumb, which is no longer possible in this patient. In contrast, the mechanism of action of the intrinsic muscles, via their contributions to the extensor tendon mechanism, allows the patient to extend the IP joint of the thumb only to a neutral position.

Control of edema is appropriate for patients who have joint stiffness or loss of motion due to swelling of the soft tissues. Removal of sutures is indicated following wound healing but will not address the functional EPL deficit. Sensory re-education is used to optimize functional outcome in patients with sensory nerve injuries. Arthrodesis of the MP joint can be performed to relieve severe posttraumatic arthritis, not acute tendon lacerations.

References
1. Doyle JR. Extensor tendons Ð acute injuries. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;2:1950.
2. Minamikawa Y. Extensor repair and rehabilitation. In: Peimer CA, ed. Surgery of the Hand and Upper Extremity. New York, NY: McGraw-Hill, Inc; 1996;1:1163.

A 75-year-old woman with severe carpal tunnel syndrome has impaired movement of the right thumb. Once the thumb is positioned correctly, it can oppose. Which of the following tendon transfers will best improve thumb motion in this patient?

(A) Abductor digiti minimi (Huber)
(B) Extensor carpi ulnaris (Phalen/Miller)
(C) Extensor indicis proprius (Burkhalter)
(D) Flexor digitorum superficialis of the ring finger (Bunnell)
(E) Palmaris longus (Camitz)

The correct response is Option E.

In this 75-year-old woman who has severe carpal tunnel syndrome, the palmaris longus tendon should be transferred to improve thumb motion. Patients with severe carpal tunnel syndrome are often unable to fully clear the thumb from the palm. The Camitz abductorplasty can be used to augment the abductor pollicis brevis tendon with the palmaris longus.

In contrast to an abductorplasty, a true opponensplasty restores thumb-finger opposition. Opponensplasties vary according to their point of insertion and associated pulleys. The Bunnell opponensplasty involves transfer of the flexor digitorum superficialis tendon of the ring finger, while the Huber opponensplasty transfers the abductor digiti minimi tendon. The Phalen-Miller opponensplasty is a transfer of the extensor carpi ulnaris tendon, and the Burkhalter opponensplasty involves transfer of the extensor indicis proprius tendon.

References
1. Green DP. Radial nerve palsy. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;2:1481-1496.
2. Imbriglia JE, Hegberg W. Radial nerve reconstruction. In: Peimer CA, ed. Surgery of the Hand and Upper Extremity. New York, NY: McGraw-Hill, Inc; 1996;2:1361-1397.

Which of the following tendons comprise the compartment that forms the volar border of the anatomic snuff box?

(A) Abductor pollicis brevis and extensor pollicis longus
(B) Abductor pollicis longus and extensor pollicis brevis
(C) Extensor digitorum communis and extensor indicis proprius
(D) Extensor pollicis longus and abductor pollicis longus
(E) Flexor carpi radialis and flexor pollicis longus

PHOTO

Reproduced with permission of Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;2:1951.

The correct response is Option B.

The volar border of the anatomic snuff box is comprised of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendons (first dorsal compartment). The dorsal border is comprised of the extensor pollicis longus (EPL) tendon (third dorsal compartment).

The above diagram shows the dorsal compartments of the forearm. The abductor pollicis brevis tendon is the most radial component of the thenar musculature; the extensor digitorum communis (EDC) and extensor indicis proprius (EIP) tendons are found in the fourth dorsal compartment. The flexor carpi radialis (FCR) tendon can be found radial to the other tendons within the superficial compartment of the volar forearm at the level of the wrist. The flexor pollicis longus (FPL) tendon lies within the deepest compartment of the volar forearm.

Reference
1. Doyle JR. Extensor tendons Ð acute injuries. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;2:1851-1897.

A 33-year-old machinist has high median and ulnar nerve paralysis after sustaining a gunshot wound to the nondominant right elbow. Which of the following tendon transfers is most appropriate for opponensplasty in this patient?

(A) Abductor digiti quinti
(B) Extensor indicis proprius
(C) Flexor digitorum superficialis of the ring finger
(D) Flexor pollicis longus
(E) Palmaris longus

The correct response is Option B.

In order for a tendon transfer to be successful, the muscle-tendon unit must be available, of appropriate strength, and able to be spared at the donor site (ie, function of the muscle cannot be critical to the site). The strength of the antagonist muscle must also be opposed, intercalary joints should have appropriate mobility, and the excursion and direction of the muscle should be well matched. In addition, the proposed tendon transfer should demonstrate integrity and synergy.

In this 33-year-old man who has developed high median and ulnar nerve paralysis, the extensor indicis proprius is the only tendon of those listed that still has motor innervation. The patient's injuries preclude the use of all muscle-tendon units powered by the paralyzed nerves. However, because the index finger has two independent extensor tendons, the extensor indicis proprius tendon can be used in tendon transfer.

A viable abductor digiti quinti muscle-tendon unit can be used for reconstruction in patients with thumb hypoplasia; this is known as the Huber opponensplasty. The flexor digitorum superficialis tendon of the ring finger can be used for opponensplasty when motor innervation is adequate; likewise, the function of the flexor pollicis longus tendon will most likely be restored with a transfer of the brachioradialis tendon. Transfer of the palmaris longus tendon to the abductor pollicis brevis tendon (Camitz transfer) is an abductorplasty, not an opponensplasty.

References
1. Smith RJ. Tendon transfers following injuries about the elbow. In: Tendon Transfers of the Hand and Forearm. Boston, Mass: Little, Brown & Co; 1987.
2. Smith RJ. Tendon transfers to restore thumb opposition. In: Tendon Transfers of the Hand and Forearm. Boston, Mass: Little, Brown & Co; 1987.

A 36-year-old woman has a boutonniere deformity of the right middle finger after sustaining a closed central slip injury while playing volleyball two months ago. She is able to extend the proximal interphalangeal (PIP) joint passively to 0 degrees.

Which of the following is the most appropriate management?

(A) Buddy taping of the PIP joint
(B) Splinting the distal interphalangeal joint at 0 degrees
(C) Splinting the PIP joint at 0 degrees
(D) Primary repair of the PIP joint
(E) Open repair of the PIP joint

The correct response is Option C.

This patient has a boutonniere deformity, in which the extensor mechanism (comprised of the central slip, transverse and oblique retinacular ligaments, and lateral bands) becomes imbalanced. In patients with this deformity, the central slip is damaged and the transverse retinacular ligament is stretched. The lateral bands begin to drift volarly, eventually moving anterior to the center of rotation of the proximal interphalangeal (PIP) joint. As a result, the lateral bands flex the PIP joint, and passive extension of the PIP joint becomes impossible.

There are three stages of boutonniere deformity. Patients with stage 1 deformities can passively extend the PIP joint. With stage 2, the joint becomes contracted and cannot be extended fully, but the joint itself is not yet involved. Degeneration of the joint is seen in a patient with a stage 3 boutonniere deformity.

Because this patient has only a stage 1 boutonniere deformity, the most appropriate management is splinting the PIP joint in extension (ie, at 0 degrees) for a minimum of six to eight months. The distal interphalangeal (DIP) joint should be unencumbered and allowed to flex actively, and an exercise program should be initiated for joint rehabilitation.

Buddy taping is only useful for certain types of injuries involving the collateral ligament and volar plate. Splinting of the DIP joint in extension is appropriate for treatment of a mallet finger deformity. Primary repair and open repair are difficult procedures and are not advocated as management options for patients with stage 1 deformities.

References
1. Burton RI, Melchior JA. Extensor tendons - late reconstruction. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;2:1988-2021.
2. Coons MS, Green SM. Boutonniere deformity. Hand Clin. 1995;11:387-402.