Hand Flashcards

Question

Flexor pulley system

Answer 1

- 5 annular (A1, A3, A5 centered over joints) - 3 cruciform - A1, A2, C1, A3, C2, A4, C3, A5 - prevent bowstringing - A2 and A4 are most important to prevent bowstringing!!

Answer 2

- origin: radius/coronoid process/IOM - insertion: base of P2 of thumb - MOST RADIAL STRUCTURE IN CARPAL TUNNEL - AIN innervated - 2 annular pulleys - 1 OBLIQUE PULLEY (most important to prevent bowstringing)

Answer 3

- 1: distal to FDS insertion - 2: prox edge of pulleys (distal palmar crease) to FDS insertion; NO MAN'S LAND - 3: Distal transverse carpal ligament to pulley system - 4: Carpal tunnel 5: musculotendinous junction to proximal edge of transverse carpal ligament

Answer 4

- many potential spaces (radial/ulnar bursae, dorsal, midpalmar, thenar/hypothenar, parona's, interdigital) - RADIAL BURSA and flexor sheath thumb contiguous - ULNAR BURSA and flexor sheath small finger contiguous - 50-80% OF ULNAR AND RADIAL BURSAE COMMUNICATION (this is the reason why you can get a horseshoe abscess w/ flexor tendon sheath injury via communication thru Parona's (quadrilateral) space

Answer 5

dorsal: pronator quadratus palmar: digital flexor tendons ulnar: flexor carpi ulnaris radial: flexor pollicis longus - infections here can lead to acute carpal tunnel syndrome because of compression

Answer 6

- ABDuctor pollicis brevis (APB) (median) - Opponens pollicis (median) - ADDuctor pollicis (ulnar) - FPB (2 heads)(deep head--> ulnar innervated; superficial head --> median innervated)

Answer 7

- ABDuctor digiti minimi - Flexor digiti minimi - Opponens digiti minimi - all ULNAR nerve innervated

Answer 8

- RaDial artery- Deep palmar arch - Ulnar artery- sUperficial palmar arch - 80% of people have anastamosis between deep and superficial arches - ARTERY is DEEP to the nerve on VOLAR side, and SUPERFICIAL to nerve on DORSAL SIDE. Think of increased sensation on volar side of hand, making a more superficial nerve make sense, the other side is opposite

Answer 9

- Grayson's (VOLAR/ground) - Cleland (Dorsal/ceiling) - Artery dorsal to nerve - Grayson's involved in Dupuytren's disease, Cleland is NOT

Answer 10

- 10 structures total - 4 FDS, 4 FDP, median nerve, FPL - FDS/FDP orientation is 34/25 - FPL is most RADIAL STRUCTURE in carpal tunnel - Recurrent motor branch of median nerve is OUTSIDE the carpal tunnel, but can have variable course. If median nerve laceration present, important to line up the most VOLAR-RADIAL fascicles during repair as this represents the portion that becomes the recurrent motor branch

Answer 11

- ulnar artery - ulnar nerve - MOTOR BRANCH FASCICLES = DORSAL AND ULNAR - pisiform and hamata (ulnar and radial borders), transverse carpal ligament (FLOOR of guyon's canal)

Answer 12

- motor and sensory crossover between median and ulnar nerve at forearm level - 15-20% of people - important because if you have laceration of median nerve at wrist PROXIMAL to recurrent motor branch, you can still have median nerve function because the fibers from the recurrent branch can anastomose w/ ulnar nerve fibers and distal median nerve fibers

Answer 13

direct branch from radial artery, entering distally along the dorsal ridge -RETROGRADE BLOOD SUPPLY

Answer 14

- Long thoracic nerve | - branches from C5-7 (leach w/ a key opening the scapula)

Answer 15

- weakness of the muscles innervated by the AIN, which include the flexor pollicis longus, index flexor digitorum profundus, and pronator quadratus. - can be present following blunt or penetrating trauma. It can also be seen in the absence of trauma, in which case there may be a prodrome of upper extremity discomfort, generalized fatigue, and/or fever. Clinical findings include weakness of the thumb interphalangeal (IP) joint and index DIP joint flexion, sometimes referred to as the “Playboy bunny sign.” Pronator quadratus weakness is also present; however, there is uncertainty as to the validity of manual muscle testing in determining pronator quadratus weakness. Electrodiagnostic studies demonstrate evidence of denervation (fibrillations and positive sharp waves) of the muscles supplied by the AIN. - In the setting of acute trauma exploration, decompression and repair of the AIN is indicated early. In the case of a spontaneous and sudden onset of symptoms, especially when associated with other indications of an inflammatory process, a viral or inflammatory neuritis is much more likely. In these cases, multiple studies demonstrate a high incidence of spontaneous resolution over 6 to 12 months. Although systemic corticosteroids may be of benefit in the case of inflammatory neuritis, there are no data to support their use and no data to support the use of AIN corticosteroid injection. Although surgical exploration is supported in the literature for patients who do not show improvement within 3 months of onset, immediate surgical exploration at 6 weeks is not indicated. Tendon transfers are indicated only if recovery fails to occur spontaneously or after surgical exploration of the AIN.

Answer 16

-The spiral cord seen in Dupuytren disease arises from the confluence of abnormal fascial thickening of the spiral bands, lateral digital sheet, and Grayson’s ligament. The orientation of these contributing structures results in a continuous band of fibrous tissue spiraling around the neurovascular bundle. As the developing spiral cord contractures from distal to proximal, the cord itself becomes increasingly linear and shorter, causing displacement of the neurovascular bundle both centrally and superficially. This displacement of the neurovascular bundle brings it closer to the skin and midline, making it more vulnerable to surgical trauma -Studies have demonstrated a high association between a PIP joint flexion contracture and a spiral cord (Figure 1). Spiral cords are also seen in association with a soft, fleshy mass between the proximal digital flexion crease and distal palmar crease in the interdigital space referred to as an interdigital soft-tissue mass. This represents displacement of normal subcutaneous tissues by contracture of the diseased fascia associated with the spiral cord. -A complication following surgical treatment of Dupuytren contracture is trauma to the neurovascular bundle. This can be a consequence of blunt or sharp trauma. In the case of traumatic stretch injury from retraction, vasospasm may develop. The treatment of vasospasm includes flexion, warming the digit, and application of topical medication to treat vasospasm. Allowing the newly extended digit to flex is an important first step, particularly in the case of chronic and severe PIP joint contractures. In these cases, the vessel may have shortened over time, and full extension may cause intimal trauma and secondary vasospasm. Cold is also a stimulus for reactive vasospasm, so warming the digit with warm saline irrigation can be helpful. Finally, topically applied lidocaine (without vasoconstrictive additives) can help diminish vasospasm and lead to digital reperfusion. Phentolamine is useful in cases of prolonged vasospasm secondary to administration of anesthetics containing epinephrine. Streptokinase is a thrombolytic agent that may be useful in treatment of embolic or thrombotic vascular disease. Systemic heparin is useful for digital vessel repair but should not be necessary to treat simple vasospasm. -

Answer 17

provided by the dorsal carpal branch of the radial artery and the superficial palmar branch of the radial artery. Approximately 70% to 80% of the scaphoid vascularity is from the dorsal carpal branch, which enters the scaphoid dorsally and distally and provides all the blood supply to the proximal scaphoid. The superficial palmar branch enters the scaphoid volarly and distally, and provides blood supply to 20% to 30% of the bone in the region of the distal tuberosity. The radioscaphoid ligament is a minor contributor to the blood supply of the scaphoid through arterioles and venules. The anterior interosseous artery can provide collateral circulation to the scaphoid, but is not the primary blood supply.

Answer 18

Fractures of the proximal pole of the scaphoid are inherently unstable and at high risk for nonunion. As many as one-third of these fractures go on to nonunion even with appropriate immobilization. Additionally, healing of these proximal fractures is slow and can require immobilization for 12-24 weeks until union is achieved. As such, screw fixation via a dorsal approach is the current accepted preferred treatment to minimize the risk of nonunion. This can be performed either percutaneously or through an open approach, at the discretion of the surgeon. Further randomized studies are needed. Proximal row carpectomy) or scaphoid excision and partial wrist fusion is indicated for salvage of arthritic or scaphoid nonunion advanced collapse wrists, and would not be indicated in this acute injury in a young individual.

Answer 19

Perilunate dislocations (Figure 3) are relatively rare but make up an important spectrum of carpal pathology. These injuries are typically associated with high-energy trauma such as a motor vehicle collision or a fall from height. Mayfield and associates described a series of injuries using 4 stages with predictable disruption to the scapholunate articulation (stage 1), lunocapitate articulation (stage 2), and lunotriquetral articulation (stage 3) prior to allowing for a lunate dislocation into the carpal tunnel (stage 4) through the space of Poirier. These authors distinguished these purely ligamentous “lesser arc injuries” from “greater arc injuries” in which the energy absorbed by the wrist leads to fractures of the radius, capitate, triquetrum, and ulnar styloid. On radiographic assessment, the posterior-anterior view typically shows disruption of “Gilula’s arcs,” which are formed by the proximal and distal articular surfaces of the proximal row and the proximal cortical margins of the distal row. On the lateral view, a perilunate dislocation will show a lunate that is in its normal position on the radius within the lunate fossa. The carpus will typically be displaced dorsally. A lunate dislocation (stage 4 injury) such as seen in this scenario will reveal the lunate displaced volarly into the carpal tunnel. The short radiolunate ligament remains intact in a lunate dislocation, which allows for the lunate to remain attached to the radius. The lunate typically causes direct compression of the median nerve in the carpal tunnel and is 1 reason why patients often have acute carpal tunnel syndrome. Although the bony and ligamentous injuries can be addressed electively within a few days of injury, acute carpal tunnel is a surgical emergency and should be addressed within the first few hours after diagnosis. An emergency department reduction of a lunate dislocation can be attempted and, if successful, may decrease carpal tunnel symptoms and obviate the need for emergent surgery. In cases in which the lunate is in the carpal tunnel, a combined dorsal and volar approach should be used. The volar approach allows for carpal tunnel release and direct reduction of the lunate. The dorsal approach allows for better visualization of the carpus and fixation of associated bony fractures and ligament injuries. Closed reduction and pinning can lead to worse outcomes following treatment.

Answer 20

A volar thumb MP joint dislocation is an uncommon injury, occurring much less often than dorsal dislocation. Thumb volar MP dislocations often necessitate an open reduction because of interposed tissue including the EPL, extensor pollicis brevis (EPB), dorsal capsule, or volar plate. Several presurgical factors are associated with failure of a closed reduction. A closed reduction is less likely to be successful with no palpable EPL, displacement of the EPL or EPB, interposed sesamoids on radiographs, and paradoxical MP joint flexion and interphalangeal joint extension on attempting MP extension. The dorsal capsule is often noted to be disrupted following the injury, but this does not necessarily lead to an irreducible joint. The APL tendon inserts on the base of the thumb metacarpal and is not involved in the pathoanatomy of an irreducible MP dislocation. A collateral ligament injury is often associated with a volar thumb MP dislocation regardless of the ability to perform a closed reduction.

Answer 21

Patient age

Answer 22

Patient age

Answer 23

C5-T1 typically - Occasionally C4 (prefixed) or T2 (postfixed) - traverse between scalene anterior and scalene medius - Dorsal scapular nerve (C5) - Long thoracic nerve (C5,6,7)!!

Answer 24

- Upper (C5 and C6; Suprascapular nerve) - Middle (C7) - Lower (C8 and T1)

Answer 25

Split above the clavicle

Answer 26

- named from relationship to axillary artery - Lateral (anterior divisions of upper and middle trunk) - Medial (anterior division of lower trunk) - Posterior (posterior divisions of all three trunks)

Answer 27

- superficial and lateral to axillary artery - lateral pectoral nerve - musculocutaneous nerve - contribution to median nerve

Answer 28

- Medial to axillary artery - Medial pectoral nerve - Medial brachial cutaneous nerve - Medial antebrachial cutaneous nerve - Ulnar nerve - Contribution to median nerve (along w/ lateral cord)

Answer 29

- posterior to axillary artery - upper and lower subscapular nerves (C5,6) - thoracodorsal nerve (C6,7,8; innervates Lattisimus Dorsi; BETWEEN SUBSCAPULAR NERVES) - axillary nerve (TERES MINOR, DELTOID) - radial nerve

Answer 30

- Musculocutaneous (C5,6,7) - Axillary (C5,6) - Radial (C5,6,7,8,T1) - Median (C5,6,7,8,T1) - Ulnar (C7,8,T1)

Answer 31

1: Elbow flexion 2: Stable shoulder 3: Hand function

Answer 32

- Carpal tunnel syndrome (most common level for radiculopathy) - Pronator syndrome - AIN syndrome

Answer 33

- Cubital tunnel syndrome | - Ulnar tunnel syndrome (Guyon's)

Answer 34

- PIN syndrome - Radial tunnel syndrome - Radial sensory nerve compression

Answer 35

- Durkin's carpal tunnel compression test | - Semmes Weinstein monofilament test

Answer 36

- Distal motor latency >4.5 msec - Distal sensory latency >3.5 msec - Decreased action potential amplitude - Decrease conduction velocity - Increased insertional activity, fibrillations, positive sharp waves on EMG (APB muscle)

Answer 37

- entrapment of MEDIAN nerve by lacertus fibrosis and/or pronator teres - effects motor and sensory - differentiate from CTS by PROXIMAL FOREARM PAIN AND SENSORY DISTURBANCES IN PALMAR CUTANEOUS NERVE DISTRIBUTION - Tinel's sign over proximal forearm - rarely requires surgery, treat conservatively; often associated w/ medial epicondylitis

Answer 38

- primarily a motor nerve that branches from MEDIAN nerve about 4-6 cm from elbow - AIN innervates: FPL, FDP to index/middle, PQ - may be compressed by GANTZER'S MUSCLE (accessory head of FPL) - Viral etiology most common - ill-defined forearm pain - inability to flex thumb IP or index DIP - PARSONAGE-TURNER BRACHIAL NEURITIS may present as AIN palsy - tx is typically observation after you rule out compressive lesions

Answer 39

- arcade of struthers - anconeus - cubital tunnel (osbourne's ligament) - 2nd most common entrapment neuropathy - WARTENBERG SIGN FIRST TO APPEAR (abducted small digit d/t weakness of IO and unopposed EDM) - Froment sign (weak thumb adduction w/ compensatory FPL flexion during pinch) - Clawing of ulnar digits - Conduction velocity difference of 10 m/s above and below elbow considered abnormal - Tx conservatively for 3 months, surgery if non-op fails

Answer 40

- entrapment of ulnar nerve at GUYON'S CANAL - 3 zones of entrapment - think mass lesion! - if concomitant CTS, release of CTS sufficient for decompression of ulnar tunnel

Answer 41

- fascial band at radial head - recurrent LEASH OF HENRY - ECRB leading edge - Arcade of Frohse (most common; proximal supinator) - distal supinator - Motor deficit - difficulty extending digits at MP joints and thumb IP joint; wrist extension w/ radial deviation - Rule out space occupying lesion; if no improvement in 1-3 months, surgical decompression

Answer 42

- pain syndrome (no motor or sensory deficit) from lateral elbow to radial forearm - compression sites similar to PIN - ARCADE OF FROHSE most common - TTP over mobile wad, pain w/ resistive supination or passive forearm pronation - associated w/ lateral epicondylitis - EMG and NCS typically normal - Tx similar to PIN syndrome

Answer 43

- Wartenberg syndrome, Cheiralgia Paresthetica - nerve travels between brachioradialis and ECRL tendons - sx paresthesias in dorsal-radial hand, ill-defined pain in radial forearm and wrist - signs: tinel's in distal forearm - diagnose by wrist block, exclude De Quervain's - tx w/ splinting and activity modification, surgery is rarely indicated

Answer 44

EIP to EPL

Answer 45

1. What works? 2. What's available? (be certain that after transfer, at least one wrist flexor and extensor and one digital flexor and extensor remains) 3. What's needed? (needed functions, not muscles) 4. Matching (match needed functions and available muscles based on principles) 5. Alternatives (capsulodesis, tenodesis, arthrodesis)

Answer 46

-Brand transfer (FCR); PT to ECRB, FCR to EDC, PL to EPL

Answer 47

A comminuted proximal ulnar fracture is often plated in a shortened position, forcing the radial head into a nonanatomical position. Attempted reduction and pin fixation without addressing the length of the ulna often results in failure, even with a ligament reconstruct. Radial head excision is a salvage procedure. A helpful technique for comminuted proximal ulna fractures is to first pin the radial head in a reduced position and then plate the ulnar out to length.

Answer 48

Ray resection, which was pioneered by Bunnell in the 1920s, was initially performed as a salvage procedure for dysfunction of the proximal interphalangeal joint. Successful ray resection with or without an adjacent ray transfer can be useful for treating vascular insufficiency, tumors, infection, trauma, recurrent Dupuytren contracture, and congenital abnormalities of the hand. Indications, techniques, and outcomes vary based on the digit and the number of digits resected. Compared with amputation at the proximal phalangeal level, a single ray resection has better cosmesis and similar function, resulting in improved patient satisfaction. However, a 15% to 30% loss in grip and pinch strength has been reported. Today, ray resection results in good cosmetic and functional outcomes when preservation of a functional digit is unattainable or when the presence of an abnormal, unreconstructable digit interferes with the overall hand function.

Answer 49

PIP joint extension

Answer 50

Pronator teres muscle transfer

Answer 51

In 8 of 18 patients (44%) the fingers continued to trigger after A-1 pulley release. In children, trigger fingers are different from trigger thumbs. Trigger fingers in children are uncommon and have variable causes, and an A-1 pulley release alone will not always correct the triggering. Additional treatments, such as resection of one or both limbs of the sublimis tendon or an A-3 pulley release, may be required. An awareness of other contributing factors and readiness to explore the entire flexor mechanism should help prevent failure of surgical treatment.

Answer 52

STT joint arthritis must be addressed at the time of CMC arthroplasty by soft tissue excisional arthroplasty of the proximal trapeziod. Hyperextension of the MCP joint, if left untreated will produce a deforming force that will cause recurrent thumb metacarpal subluxation. It therefore should be addressed at the time the CMC joint is treated surgically. -Thumb abduction and extension is the functional thumb position that a successful arthroplasty will achieve

Answer 53

Both dorsal and volar PIP dislocations are associated with injury to the collateral ligaments. However, in a dorsal dislocation, the volar plate is injured; in a volar dislocation, the central slip is either ruptured or detached from its insertion on the base of the middle phalanx. Although closed reduction is appropriate, following reduction, the central slip detachment must be appropriately addressed, either with immobilization of the PIP in extension or with surgical repair. In the absence of surgery, the central slip insufficiency will lead to formation of a boutonniere deformity. A swan-neck deformity will develop with a volar plate injury, causing PIP hyperextension and secondary DIP flexion. Mallet deformity is a flexion deformity of the DIP joint secondary to terminal extensor avulsion from the distal phalanx. A central slip avulsion from the PIP joint will result in a PIP flexion deformity. The triangular ligament ruptures, allowing migration of the lateral bands in a volar direction, producing a hyperextension posture of the DIP joint with minimal active DIP flexion

Answer 54

The gold standard for the treatment of gaps in major peripheral nerves is cabled autografting. Allografts and conduits are beneficial and have their own indications; however, studies have not demonstrated equivalent outcomes compared to those achieved with autografts

Answer 55

The imaging studies show an established scaphoid waist nonunion with a humpback deformity (significant flexion through the nonunion site) and carpal collapse. In addition, the proximal pole appears sclerotic on the plain radiographs and appears poorly perfused on the MR image. Correction of alignment of this scaphoid nonunion would require a volar approach with a structural bone graft. Additionally, the graft would need to provide a vascular supply to the bone. Both the 1,2 ICSRA (the Zaidenberg graft) and the 4+5 ECA grafts are vascularized grafts from the dorsal distal radius. Neither of these grafts would correct the humpback deformity, and the 4+5 ECA graft pedicle is not long enough to reach the scaphoid. An iliac crest bone graft could be used to correct the deformity, but neither iliac crest autograft nor cancellous distal radius autograft would provide an adequate blood supply. A free-vascularized medial femoral condyle graft provides both adequate bone graft to correct the deformity and revascularization of the scaphoid.

Answer 56

Both the 1,2 ICSRA (the Zaidenberg graft) and the 4+5 ECA grafts are vascularized grafts from the dorsal distal radius. Neither of these grafts would correct the humpback deformity, and the 4+5 ECA graft pedicle is not long enough to reach the scaphoid. An iliac crest bone graft could be used to correct the deformity, but neither iliac crest autograft nor cancellous distal radius autograft would provide an adequate blood supply. A free-vascularized medial femoral condyle graft provides both adequate bone graft to correct the deformity and revascularization of the scaphoid.

Answer 57

1. Finger tip: V-Y advancement flap (if straight or dorsal oblique); cross finger or thenar flap (if volar oblique) 2. Volar proximal finger: cross finger 3. Dorsal proximal finger and MCP: Reverse cross finger 4. Volar thumb: Moberg Advancement volar flap or FDMA 5. Dorsal thumb: FDMA 6. First web space: Z-plasty w/ 60 deg flaps 7. Groin flap

Answer 58

Frostbite injuries should be treated with limited debridement of nonhemorrhagic blisters initially. Escharotomy is indicated if circulation is compromised by eschar or compartment syndrome develops. With intact circulation, amputation should be delayed until the necrotic tissue has clearly demarcated, a process that may take several months.

Answer 59

- Identified nerve injury - CRPS 2 develops after nerve injury, whereas CRPS 1 occurs without nerve injury. The diagnostic criteria are otherwise the same for the 2 conditions. A 3-phase bone scan can be helpful; a pattern of increased uptake in all 3 phases, and particularly diffuse periarticular uptake in and around the joints of the affected extremity during the delayed phase, is considered typical of CRPS, especially during the first 6 months; however, it is not specific enough to be used as a diagnostic criteria.

Answer 60

Cubital tunnel syndrome is the second-most-common compressive peripheral neuropathy after carpal tunnel syndrome. The diagnosis is typically established through a combination of a supportive history, positive clinical signs, and electrodiagnostic studies. Patients often experience hand paresthesias and/or numbness and hand pain (and less commonly medial elbow pain). Numbness usually affects the small finger, the ulnar aspect of the ring finger, and the dorsum of the hand (via the dorsal cutaneous branch of the ulnar nerve). When symptoms affect motor function, patients will have weakness of the hand intrinsics muscles and may exhibit atrophy. The Wartenberg sign is the observation of an abducted posture of the small finger in an affected hand attributable to an imbalance caused by an intact extensor digiti minimi and functional impairment of the affected third volar interosseous muscle attributable to atrophy and weakness. There are many surgical options for cubital tunnel syndrome, but all share division of the Osborne ligament because the nerve passes anterior to the olecranon and posterior to the medial epicondyle at the elbow.

Answer 61

Ulnar nerve compression at Guyon’s canal will cause numbness to the small finger and intrinsic muscle weakness but not numbness to the dorsum of the hand because the dorsal ulnar sensory nerve branches from the ulnar nerve prior to Guyon’s canal.

Answer 62

- between the 2 head of FCU/aponeurosis (most common) - within arcade of struthers (hiatus in medial intermuscular septum) - between Osborne's ligament and MCL

Answer 63

The spiral cord seen in Dupuytren disease arises from the confluence of abnormal fascial thickening of the spiral bands, lateral digital sheet, and Grayson’s ligament. The orientation of these contributing structures results in a continuous band of fibrous tissue spiraling around the neurovascular bundle. As the developing spiral cord contractures from distal to proximal, the cord itself becomes increasingly linear and shorter, causing displacement of the neurovascular bundle both centrally and superficially. This displacement of the neurovascular bundle brings it closer to the skin and midline, making it more vulnerable to surgical trauma. Studies have demonstrated a high association between a PIP joint flexion contracture and a spiral cord (Figure 1). Spiral cords are also seen in association with a soft, fleshy mass between the proximal digital flexion crease and distal palmar crease in the interdigital space referred to as an interdigital soft-tissue mass. This represents displacement of normal subcutaneous tissues by contracture of the diseased fascia associated with the spiral cord. Dupuytren diathesis, MCP joint contracture, and the presence of knuckle pads are not indicative of a spiral cord.

Answer 64

Improved tendon gliding | -If repair of the FDS in addition to the FDP is too bulky, then resection of one FDS slip decreases gliding resistance

Answer 65

From 1977 to 1988, 166 patients with median nerve paralysis of varied aetiology underwent opponensplasty. In 50 of these the extensor indicis was used, and in 116 the flexor digitorum superficialis of the ring finger. An analysis of these hands showed that the EI opponensplasty was best in supple hands and FDS opponensplasty was more suitable for less pliable hands. There were fewer complications seen after FDS opponensplasty if the detachment of the donor tendon was done through a volar oblique incision rather than the conventional lateral incision.

Answer 66

- initial choice is FCR tendon | - if FCR tendon avulsed, attenuated, or inadvertently detached, then salvage option is using the ECRL

Answer 67

Dorsal approach to a displaced proximal scaphoid fracture allows access to the fracture for reduction and easier insertion of a central screw. Displaced scaphoid fractures (> 1 mm) or those involving deformity (intrascaphoid angulation > 45 degrees) are treated with ORIF.

Answer 68

occur in the web space and must be treated with both volar and dorsal drainage. Dorsal incision will not adequately drain the abcess. A key characteristic upon examination is abduction/spread of the affected fingers.

Answer 69

Lateral antebrachial cutaneous neuropraxia! -The distal biceps tendon is commonly torn with an eccentric contraction of the biceps when the elbow is taken into extension. Patients treated nonsurgically will note loss of at least 50% supination strength and may develop discomfort with resistive activities. The video shows the squeeze test to evaluate the integrity of the biceps tendon. The test is similar to the Thompson test in the evaluation of an Achilles tendon rupture. The distal arm is squeezed with the elbow flexed 60 to 80 degrees and the forearm pronated. By shortening the musculotendinous unit, the intact biceps tendon will lead to forearm supination. If the biceps is torn, the forearm will not supinate as shown in the video. The maneuver is performed with the elbow in flexion to minimize tension on the brachialis muscle and isolate the biceps. Ruland and associates evaluated 25 patients with suspected distal biceps ruptures and correctly diagnosed all but 1 false-positive result that involved a partial tear. The lacertus fibrosus is not evaluated with this maneuver. When considering a repair, a 1- or 2-incision technique may be performed. Chavan and associates performed a systematic review comparing the 2 techniques and reported similar complication rates. The 2-incision technique was associated with more instances of significant loss of forearm rotation and more unsatisfactory clinical results. The 1-incision technique is associated with a higher incidence of lateral antebrachial cutaneous neuropathy likely attributable to retraction. The biceps insertion is a thin semilunar area on the posterior/ulnar aspect of the radial tuberosity centered at approximately 30 degrees anterior to the lateral/coronal plane with the arm fully supinated. Forthman and associates used CT scan to asses 30 cadaveric specimens and noted that the biceps tuberosity orientation would prohibit an anatomic repair in 35% of arms for which the 1-incision technique was used. Mazzocca and associates reported the highest load to failure of the Endobutton (440 newton (N)) compared to fixation with suture anchor (381 N), Wartenberg syndrome (310 N), and an interference screw (232 N). Greenberg and associates noted greater load to failure for the Endobutton (584 N) compared to suture anchor (254 N) and transosseous tunnel (178 N) constructs. Spang and associates reported comparable strength of the Endobutton repair when compared to suture anchors. Fifty N of force is required to hold the elbow flexed at 90 degrees against gravity, which is well below the strength of the repairs studied. Neuropraxia of the lateral antebrachial cutaneous nerve branch is the most common complication associated with distal biceps repair, with a reported incidence as high as 40%. The nerve branch lies between the biceps and brachialis as it crosses the surgical field in the antecubital fossa. The neuropathy may be related to aggressive retraction, particularly when using the 1-incision technique, and often resolves with time. Cain and associates reported minor complications were common (but major complications uncommon) following distal biceps repair. Reported complications arelateral antebrachial cutaneous paresthesia (26%), radial sensory nerve paresthesia (6%), posterior interosseous nerve injury (4%), and rerupture (2%).

Answer 70

PIP joint flexion contracture

Answer 71

-21-40% successful union rate It is well known that tobacco use has a negative effect on fracture healing. Little and associates’ study showed that union was achieved in 47 of 64 cases with nonvascularized scaphoid bone grafting with internal fixation. However, 13 of the 17 patients with a nonunion were smokers, revealing only a 24% success rate. A Mayo Clinic study assessing the success of vascularized bone graft on scaphoid nonunion in smokers showed success rate of only 46%. An additional study revealed a success rate of only 40% among smokers. A study by Nåsell and associates showed that the effect of smoking cessation intervention on all patients undergoing surgery for acute fractures of both upper and lower extremities during the first 6 weeks after surgery was beneficial. The overall complication rate in this study was lowered by 18%. A smoking cessation intervention during the perioperative period for surgery for scaphoid nonunion may provide some fracture-healing benefits.

Answer 72

Cubital tunnel syndrome is the second-most-common compression neuropathy (after carpal tunnel syndrome). Advanced ulnar neuropathy is characterized by numerous eponymous signs and by motor atrophy (eg, fist dorsal interosseous, adductor pollicis). The first sign to appear is the Wartenberg sign (Figure 89), which involves the small finger resting in an abducted position because of unopposed pull of the extensor digiti minimi (because interossei are weak from ulnar neuropathy). Froment’s sign (Figure 92) is also seen in advanced ulnar neuropathy secondary to weakness of the adductor pollicis and first dorsal interosseous and compensation by the flexor pollicis longus (FPL) (median innervated) and extensor pollicis longus (radial innervated). The AIN provides motor to the FPL, flexor digitorum profundus (FDP) to the index and middle fingers, and to the pronator quadratus. AIN palsy is a motor deficit that can affect all or part of those muscles. Figure 90 shows a “flattened” OK sign that is seen in AIN palsy attributable to weakness of the FPL and FDP to the index finger. PIN palsy is also a pure motor syndrome. It affects the finger and thumb extensors and the extensor carpi ulnaris (ECU) and extensor carpi radialis brevis (ECRB). The extensor carpi radialis longus (ECRL) is innervated by the radial nerve, so, in PIN palsy, the patient will have a weak wrist extension (because there is no ECU and ECRB involvement) in slight radial deviation (because only the ECRL is firing). Low median nerve palsy is a deficit of the median nerve at the wrist/carpal tunnel. As such, the primary motor deficit is of the thenar muscles and, clinically, this results in weakness in opposition attributable to abductor pollicis brevis weakness. This is often treated with an opposition transfer (tendon transfer). Ulnar tunnel syndrome is compression of the ulnar nerve at the wrist. It is less common than cubital tunnel syndrome. The most common etiology is a ganglion cyst, and MRI is helpful when assessing for this condition. Other etiologies include hypothenar hammer syndrome, hook-of-the-hamate fractures, and anomalous muscles.

Answer 73

- purely motor palsy (though does provide sensory innervation to dorsal wrist capsule thru terminal branch located on the floor of 4th extensor compartment) - ECRB - EDC - EDM - ECU - supinator - APL - EPB - EPL - EIP - in PIP compression syndrome the last muscle to recover is the EIP!

Answer 74

Midline and volar

Answer 75

Treatment begins with closed reduction and careful assessment of the restoration of joint congruity and stability. If anatomic reduction with acceptable stability is achieved with closed reduction, immobilization with or without pinning the joint in a reduced position can be performed; with persistent instability following reduction, further stabilization is needed. If anatomic reduction is not possible with closed reduction, open reduction should be performed. This can be supplemented with pinning the joint in a reduced position for 4 to 6 weeks. Alternatively, primary reconstruction of the volar oblique ligament can be performed to restore joint stability (this is suggested by some authors). Carpometacarpal arthrodesis should be saved for salvage or for symptomatic arthritis in a young laborer. There is no thumb metacarpal fracture, so open reduction and internal fixation is not indicated. However, clinicians must be cognizant regarding a possible Bennett fracture.

Answer 76

- superior, middle, and inferior - superior trunk has 2 branches, suprascapular nerve and branch to subclavius - middle and inferior have no terminal branches

Answer 77

- 1 incision: larger arc of forearm rotation, more satisfactory clinical result, but higher risk of lateral antebrachial cutaneous neuropraxia - 2 incision: more anatomic placement of repair - Endobutton is best!

Answer 78

Crush injury through the index finger middle phalanx in adult -Replanting should be attempted for children with digit amputations, especially if multiple digits on the same hand are involved. Any laceration through the mid palm or proximal phalanx should be replanted. A crush injury to a border digit through zone 2 in an adult is a relative contraindication because of likelihood for stiffness and cold intolerance.

Answer 79

1 cm directly distal to Lister tubercle -Most wrist arthroscopy begins with placement of the 3,4 portal because this portal can reliably be placed without injury to adjacent structures. The 3,4 portal is located just distal to the Lister tubercle between the extensor pollicis longus (EPL) and EDC tendons. Typically, the potential portal location is localized with a needle and saline injection of the joint. The other responses can result in injury to the EPL or EDC tendons

Answer 80

- Radial collateral ligament stability - PIP joint arthroplasty is a surgical treatment option for patients with PIP joint arthritis. However, this procedure is dependent upon radial collateral ligament stability, even when a 1-piece silicone implant is used. A key pinch or pinching the thumb tip to the radial aspect of the index finger middle phalanx places tremendous load on the radial collateral ligament of the index PIP joint. Presurgical instability, surgical technique, and surgical dissection are important variables; arthroplasty may threaten the integrity of the ligament. As a result, most surgeons will recommend PIP joint fusion for the index finger, which plays a role in key pinch, and will offer PIP joint arthroplasty for the long and ring fingers, for which there is less thumb-to-side pinching and motion is a priority. Arthrodesis limits motion but is associated with better reliability over the long term compared to arthroplasty for the PIP joint of the index finger. Infection is no more likely at the index PIP joint than at any other joint. Although a silicone (1-piece) arthroplasty may help in cases of collateral ligament instability, it is not required if the radial collateral ligament can be preserved or satisfactorily reconstructed. Both volar and dorsal approaches for PIP arthroplasty have been described without producing conclusive evidence demonstrating superiority of 1 approach over the other.

Answer 81

There is full passive correction of the deformity (Figure 2). The radiograph does not show subluxation of the distal phalanx on the middle phalanx (Figure 3), so the most important part of this treatment is to maintain the DIP joint in full extension for 6 to 8 weeks. This can be done with a dorsal or volar DIP joint splint with the proximal interphalangeal (PIP2) joint free. PIP motion should be encouraged but is not the hallmark of treatment. The DIP joint should not be allowed to flex for the period of immobilization. Attention should be paid to the health of the dorsal skin. A transarticular Kirschner wire can be used to maintain extension for a patient who would have difficulty performing his or her occupation, such as a surgeon or dentist. Night splinting may be continued for another month. The fracture fragments do not need to be anatomically aligned.

Answer 82

This patient likely sustained a scapholunate ligament injury years prior that has led to arthritic changes. The radiographs demonstrate a stage IV scaphoid lunate advanced collapse (SLAC) wrist. Treatment options for a stage IV SLAC wrist include scaphoid excision with 4-corner fusion, full-wrist fusion, or total wrist arthroplasty. Considering the patient’s age and the arthritic changes about the proximal pole of the capitate, scaphoid excision and intercarpal fusion is the most appropriate procedure. Proximal row carpectomy is not indicated because of this patient’s age and arthritic changes about the proximal pole of the capitate. Wall and associates reported a higher probability of failure with PRC among patients younger than age 40. STT arthrodesis is not indicated because this would lead to increased load through the arthritic radio-scaphoid articulation. Scapholunate ligament reconstruction is not appropriate for this patient because of the wrist arthritic changes, which necessitate a salvage procedure.

Answer 83

Numbness predominantly or exclusively in median nerve distribution 3.5 Nocturnal numbness 4 Thenar atrophy and/or weakness 5 Positive Phalen test result 5 Loss of 2-point discrimination 4.5 Positive Tinel sign result 4 A score of 12 or higher indicates a high likelihood of carpal tunnel syndrome, while a score lower than 5 indicates low likelihood.

Answer 84

Radiolunate -Scapholunate-advanced collapse progresses in a predictable pattern that starts with the distal radioscaphoid articulation and then involves the proximal radioscaphoid and joints and ends with pancarpal arthritis. The lunate fossa is usually spared until very late involvement because of the spherical shape of the lunate in its articulation. Scaphoid nonunion advanced collapse follows a similar pattern, except the proximal side of the scaphoid moves and behaves like the lunate, which is being spared.

Answer 85

Excision of the proximal third of the trapezoid! -Multiple factors can lead to incomplete pain relief following trapeziectomy. The prevalence of concomitant scaphotrapezoid arthritis at the time of trapeziectomy has been reported by Tomaino and associates to be as high as 62%. This patient’s radiographs demonstrate scaphotrapezoid arthritis in addition to Eaton stage IV pantrapezial arthritis. Resection of the proximal third of the trapezoid should be considered at the time of surgery. There are no significant arthritic changes at the MP joint, precluding the need for MP arthrodesis. Hematoma arthroplasty involves resection of the trapezium and pinning the thumb metacarpal without ligament reconstruction. The results of hematoma arthroplasty are comparable to trapezium resection with ligament reconstruction. Prosthetic implant arthroplasty will address the trapeziometacarpal arthritis. The implants have demonstrated acceptable short-term results but are associated with a high complication rate, and revision often is necessary.

Answer 86

Initial tx w/ silver nitrate has an 85% success rate w/ avg of 1.6 applications. If this fails, then wide surgical excision is associated w/ lowest recurrence rate.

Answer 87

Thumb pulp -Use of the Moberg flap requires an independent dorsal blood supply for digit viability as seen in the thumb but not predictably in the fingers. The Moberg flap is best used to address volar pulp defects in the thumb of up to 1 cm. Additional advancement can be achieved by exposing and mobilizing the neurovascular structures. Flexion contractures, a frequent outcome of this mobilization, are better tolerated in the thumb than in the fingers.

Answer 88

Cross-finger flap

Answer 89

A flap from the first dorsal metacarpal artery

Answer 90

skin grafts or extended dorsal metacarpal artery flaps.

Answer 91

Flexion contracture | -Overtightening of the graft commonly results in flexion contracture.

Answer 92

Many salvage procedures have been used to treat posttraumatic degenerative arthritis of the wrist related to scapholunate dissociation (SLAC) and scaphoid nonunion. Two of the more commonly used procedures are PRC and scaphoid excision with 4-corner fusion. In stage I disease, treatment of the underlying pathology (scapholunate dissociation or scaphoid nonunion) generally is possible in association with radial styloidectomy. In stage II disease, both PRC and scaphoid excision with 4-corner fusion are reasonable options. In stage III disease, the capito-lunate degeneration may compromise the efficacy of PRC, although this remains a controversial topic. In stage IV disease, total wrist fusion or arthroplasty must be considered. Outcome studies demonstrate no statistically significant differences in results following PRC and scaphoid excision with 4-corner fusion. In 1 cohort study looking at 2 groups of 19 patients, there were no major differences in motion, strength, pain relief, or functional results. Scaphoid excision with 4-corner fusion resulted in slightly better radial-ulnar deviation and grip strength than seen in the PRC group. Even though some degenerative radiographic changes were seen at the capitolunate joint in the PRC group, these changes did not correlate with clinical deterioration at 10-year follow-up.

Answer 93

The injury depicted is a volar dislocation of the proximal interphalangeal (PIP) joint. Both dorsal and volar PIP dislocations are associated with injury to the collateral ligaments. However, in a dorsal dislocation, the volar plate is injured; in a volar dislocation, the central slip is either ruptured or detached from its insertion on the base of the middle phalanx. Although closed reduction is appropriate, following reduction, the central slip detachment must be appropriately addressed, either with immobilization of the PIP in extension or with surgical repair. In the absence of surgery, the central slip insufficiency will lead to formation of a boutonniere deformity. A swan-neck deformity will develop with a volar plate injury, causing PIP hyperextension and secondary DIP flexion. Mallet deformity is a flexion deformity of the DIP joint secondary to terminal extensor avulsion from the distal phalanx. A central slip avulsion from the PIP joint will result in a PIP flexion deformity. The triangular ligament ruptures, allowing migration of the lateral bands in a volar direction, producing a hyperextension posture of the DIP joint with minimal active DIP flexion.

Answer 94

Loss of PIP joint extension

Answer 95

Treatment of a displaced or unstable distal radius fracture with a volar plate is common. The differential diagnosis of flexor pollicis longus (FPL) dysfunction after volar plating of a distal radius fracture includes scar entrapment of the FPL tendon, hardware irritation, FPL impingement or rupture, and injury to the anterior interosseous nerve. Prevalence of flexor tendon rupture after distal radius fracture is between 2% and 12%. The FPL tendon is the most common flexor tendon rupture associated with volar plating. It is usually seen with plates that are distal to the watershed line (W) and with plates extending volar to the critical line (C) (Figure 4). The watershed line (W) is the location of the origin of the volar carpal ligaments and the bone prominence at which flexor tendons are most closely opposed to the distal radius (Figure 4). In this scenario, the lateral radiograph shows that the plate is not distal to the watershed line (W) and is between the critical line (C) and the line parallel to the volar cortex of the radius (R). This is the optimal position for the plate. Placement of a volar locking plate distal to the watershed line of the distal radius and excessive plate prominence has been associated with FPL tendon rupture. This patient is only 2 weeks past surgery and there is some FPL function. FPL weakness after volar distal radius plating is common and has been seen in as many as 50% of patients. This usually recovers spontaneously by 2 months, and no treatment is needed. A nerve conduction study would be indicated if an anterior interosseous nerve compression were considered, but it is too early for this test. A CT scan could be obtained to judge the alignment of the fracture fragment and position of the screws, but it is not indicated in this case. Exploration could be performed if an FPL rupture were considered, but, because it is only 2 weeks after surgery, there is some FPL function, the plate is proximal to the watershed line, and immediate exploration is not indicated. If this does not improve after 2 to 3 months, further investigation with ultrasound or MRI would be indicated.

Answer 96

Progressive stretching and splinting program

Answer 97

-Surface replacement arthroplasty

Answer 98

Dorsal edge of first dorsal wrist compartment

Answer 99

MCP joint extension brace

Answer 100

-SILICONE replacement arthroplasty through a VOLAR approach

Answer 101

- STT joint arthritis! - Note that MCP joint hyperextension must also be addressed as it will cause deforming force that will cause recurrent thumb metacarpal subluxation otherwise

Answer 102

``` Temporary Scaphotrapeziotrapezoidal (STT) pinning -results in decrease in radiolunate contact stress while increasing load on radioscaphoid articulation ```

Answer 103

- distal radius physeal injury due to repetitive axial loading - Plain films show physeal widening and hazy irregularity

Answer 104

- Joint leveling procedure - Radius core decompression - radial wedge osteotomy - vascularized bone grafts - partial wrist fusions - proximal row carpectomy (PRC) - wrist fusion - total wrist arthroplasty

Answer 105

ulnar negative variance (thought to lead to increased forces on the lunate)

Hand Flashcards

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