UPPER EXTREMITY UPDATE
From University of Toronto Faculty of Medicine’s 24th Annual Upper Extremity Update
Educational Objectives
| The goal of this program is to reduce pain and improve function in patients with upper extremity disorders. After
hearing and assimilating this program, the clinician will be better able to:
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 | 1. Diagnose and treat patients with carpal tunnel syndrome (CTS).
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| 2. Identify patients with CTS who are likely to benefit from surgery.
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| 3. Optimize outcomes of metacarpophalangeal (MP) surgery in patients with rheumatoid arthritis (RA).
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| 4. Discuss the advantages and disadvantages of silicone and pyrocarbon MP implants in patients with RA.
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| 5. Assess patients with work-related injuries of the upper extremities.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the
planning committee to disclose relevant financial relationships within the past 12 months that might create any personal
conflicts of interest. Any identified conflicts were resolved to ensure that this educational activity promotes
quality in health care and not a proprietary business or commercial interest. For this program, the faculty and planning
committee reported nothing to disclose.
Acknowledgments
Drs. Mahoney, Axelrod, and Richards were recorded at 24th Annual Upper Extremity Update, presented by the Faculty
of Medicine, University of Toronto, and held April 11, 2008, in Toronto, ON. The Audio-Digest Foundation thanks
the speakers and the University of Toronto for their cooperation in the production of this program.
| CHANGING PERSPECTIVES ON CARPAL TUNNEL SYNDROME —James L. Mahoney, MD, Associate Professor, Department
of Surgery, Division of Plastic Surgery, University of Toronto, Faculty of Medicine, and Surgeon, Department of
Plastic, Reconstructive, and Hand Surgery, St. Michael’s Hospital, Toronto, ON
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| Impact: affects 1% of US population annually; 3% of men and 11% of women develop carpal tunnel syndrome (CTS) by
70 yr of age; cost—work-related costs, ≈$13,000 per affected employee; 450,000 surgeries performed annually, with
cost of ≈$2 billion
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| Pathophysiology: nerve compression; acute—result of fracture or blunt trauma; immediate surgical release required;
progressive damage to nerve difficult to reverse after 24 to 48 hr; permanent loss of sensory and motor function may occur;
chronic—intracompartmental compression related to slowly developing ischemia; pathologic changes involve thickening
of endoneurium and perineurium, alteration of blood-nerve barrier, nerve regeneration, and scarring; nerve
compression at level of cervical spine also may occur (double crush syndrome), exacerbating symptoms
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| Risk factors: anatomic or developmental abnormalities; rheumatoid arthritis; some metabolic conditions (including
changes that occur during third trimester of pregnancy); tumors may increase risk by increasing blood supply to carpal
canal; trauma; recent hand surgery (risk increases with inflammation); repeated flexion of wrist (typically occupational);
obesity; note—specific etiology not identified in many patients
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| Clinical findings: nighttime numbness; numbness and tingling with activity (eg, driving, using telephone, gardening);
improvement with splinting; symptoms persist for months; work-related symptoms—identify and remedy aggravating
conditions before considering surgical intervention
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| Physical examination: findings may help classify disease severity and provide clues about prognosis; establishing
baseline important for assessing response to treatment; sensory testing—light touch (compare thumb and fifth digit and
left and right hands); 2-point discrimination; strength—median nerve innervates abductor pollicis brevis distal to wrist;
muscle strength or evidence of wasting useful for assessment; Tinel’s sign—general test for eliciting nerve sensitivity;
tapping (over area of damaged nerve) precipitates nerve irritation; Phalen’s test—provocative test for CTS; holding wrist
in flexed position for 30 sec reproduces symptoms; sensitivity and specificity may be higher than previously thought;
wrist compression test—direct pressure over carpal tunnel (at wrist) for 20 to 30 sec reproduces symptoms
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| Diagnosis: standard criteria—numbness in area of median nerve distribution; Tinel’s sign; positive Phalen’s test; loss of
sensation; weakness
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| Differential and concomitant diagnoses: diabetes—increases risk for CTS; associated with superimposed diffuse peripheral
neuropathy; cervical root impingement—examine arm proximal to wrist; check for numbness and tingling; other
neuropathies—less common; include compression neuropathies; tenosynovitis and wrist pathology—may occur in
patients with CTS; identification important for management
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| Investigations: x-rays—wrist; cervical spine (if involvement suspected); electromyography (EMG) and nerve conduction
studies—gold standard; may confirm clinical suspicion but not diagnostic; useful for assessing severity and investigating
differential diagnosis; ultrasonography (US)—good sensitivity and specificity; many patients with CTS have
increased cross-sectional area of wrist, proximal to inlet of carpal tunnel
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| Nonsurgical treatment: splinting—mainstay of nonsurgical options; neutral position; most benefit seen when used
early in disease process; duration, 4 wk; pharmacologic management—oral corticosteroids (but, concern about avascular
necrosis of femoral head); local injections of corticosteroids associated with good initial response, but limited
long-term improvement (using larger doses and injecting steroid distal to wrist may improve response and reduce complications);
pyridoxine not commonly used; diuretics not helpful; nonsteroidal anti-inflammatory drugs may help
somewhat; other options—laser therapies suggested; Cochrane review—found moderate evidence in support of oral
corticosteroids (steroid injections not reviewed) and limited evidence in support of splinting, yoga, US, and carpal tunnel
mobilization; more research needed; speaker’s practice—splinting and (sometimes) corticosteroid injections for
patients with mild disease and for short-term benefit in patients with moderate disease
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| Surgery: candidates—patients with moderate disease (eg, weakness, impaired nerve conduction) most likely to receive
benefit; patients with severe disease (loss of 2-point discrimination) usually have incomplete improvement (better among
younger patients); approach—direct, with limited incision; endoscopic; proximal, using retinaculotome; outcomes—
90% improvement in numbness, pain, and paresthesia among appropriately selected patients; recovery requires ≈6 mo;
return to work may occur within 3 wk (unless occupation involves heavy physical work); Cochrane review—surgery superior
to splinting; few patients require second surgery; questionable benefit among patients with mild symptoms; more
data needed; surgical failure—no improvement in symptoms or nerve conductivity within 6 mo; complications—nerve
injury (uncommon); scar sensitivity, followed by stiffness in hand; pain at incision site (possibly related to nerve sensitivity
or injury); pillar pain (deep pain within carpal canal) precipitated by stretching carpal ligament in transverse direction;
distal approach with retinaculotome—case series showed resolution of numbness in 43% to 48% of patients and significant
improvement in ≈50%; reasons for failure of initial release—incomplete release (\>50% of cases); nerve injury
(≈5%); nerve tethered in scar tissue (≈32%); previously undiscovered tumor (2%); repeat surgery may improve outcome
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| Speaker’s protocol: carpal tunnel releases performed under local anesthetic without tourniquet; short limited
incision—just large enough to accommodate retractors; complete release—perform under direct vision; adjust light for
direct visualization; close palmar fascia; surgical time—≈30 min
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| Older patients: patients \>70 yr of age may present with numbness, reduced function, and profound muscle wasting, but
without pain; EMG studies show no conduction; outcomes of surgery—pain may increase; numbness may not improve;
function and strength may improve slightly; poorer overall satisfaction, compared with younger patients
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| MANAGEMENT OF METACARPOPHALANGEAL DISEASE IN RHEUMATOID ARTHRITIS —Terry B. Axelrod,
MD, Associate Professor, Department of Surgery, Division of Orthopaedic Surgery, University of Toronto, Faculty of Medicine
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| Hand deformation: rheumatoid arthritis (RA) often causes ulnar drift and volar subluxation, resulting in prominent
metacarpal heads and metacarpophalangeal (MP) joints, postural deformities (eg, fingers fixed in flexed position; wrist
fixed in radial posture), and dislocation of digits
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| Disease progression: proliferative phase—associated with pain, inflammation, swelling, synovial proliferation, and
angiogenesis; destructive phase—classic synovial pannus invades and erodes cartilage and soft tissues; “burnt-out”
phase—less inflammation; joints replaced by fibrous scarring and fixed deformities; affected joints—not all joints
equally affected; reason for unequal disease progression unknown
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| Ulnar drift: consists of ulnar shift and deviation, combined with volar subluxation and dislocations of MP joint;
pathomechanics—condylar structure of metacarpal head allows multiaxial movement and relies on capsule and ligaments
for stability; synovial proliferation stretches collateral ligaments; radial collateral ligament preferentially affected;
dorsal structures stretched more than palmar structures; extensor hood weakens at level of sagittal bands,
allowing ulnar subluxation of tendons; most patients have radial deviation of wrist; normal axial alignment of extensor
tendons results in forces that pull extensor tendons to ulnar side; fourth and fifth digits—absence of intermetacarpal
slings results in more extreme deformities; volar subluxation—collateral ligament weakening results in stretching of
dorsal extensor mechanism, which becomes incompetent over time; because flexors more powerful than extensors,
phalanges pulled into palmar position; resulting subluxation leads to dorsal erosion of proximal phalanges
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| Clinical consequences of deformities: severity of deformity correlates with perceived level of disability; 93% of patients
with RA have some degree of hand disability (mostly moderate); reasons for surgery—pain; loss of function; deformity
(cosmetic and psychosocial reasons); pain occurs in early stage (due to inflammation) and in late stage (due to
bone on bone arthritis); loss of function—correlates with severity of deformity; many patients with severe deformities of
MP joints function surprisingly well
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| Synovectomy: may have role in early stage of disease (eg, for joints refractory to medical management); problems recur
in 30% to 50% of patients
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| Synovectomy plus tendon relocation: indicated in early stages of disease; patient selection—well-preserved joints
without frank dislocations (perhaps some subluxation); tendon drift and some dislocation to ulnar side; pain and impaired
function; surgery—perform radial arthrotomy parallel to extensor tendon; separate tendon from underlying capsule; perform
synovectomy; release ulnar collateral ligament and ulnar intrinsic wing of extensor hood; plicate radial collateral
ligament to correct deformity; repair dorsal capsule; stabilize extensor tendon by weaving it through radial side of capsule
and back onto itself (reduces risk for surgical failure); recovery and rehabilitation—patient wears dynamic extension
splint for 6 wk; physical therapy
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| MP arthroplasty: most common surgical treatment for MP joint arthritis; choice of implant affects insertion technique
but not overall surgical approach; preparation—tourniquet; drape; infection control; incisions—2 longitudinal incisions
(better tolerated and improved wound healing, compared to transverse incision); steps—make flaps on either
side of extensor hood; expose extensor hood; perform radial peritendinous arthrotomy on radial side of MP joint; expose
metacarpal head; completely resect radial and ulnar collateral ligaments; place tag suture in radial collateral ligament;
place retractors at neck of metacarpal; resect metacarpal head with micro-oscillating saw (shortening too much
may cause instability); perform full synovectomy; open and shape base of proximal phalanx (eg, with burr and rasp);
size of implant—larger implants associated with lower rates of fracture, improved structural integrity, and less risk for
ulnar drift; technique continued—isolate and resect ulnar intrinsic wing (reduces risk for drift); release sagittal bands
on ulnar side; insert prosthesis; repair and plicate radial collateral ligament to maintain correct position of finger; perform
vest-over-pants repair of extensor tendon and capsule to centralize tendon (fix toward radial side to offset recurrence
of ulnar drift); close skin with nylon suture (patients often have delayed wound healing; sutures remain in place
for extended period; nylon suture well tolerated); wrap hand with bulky dressing
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| Outcome: soft tissue balancing critical; careful ulnar and volar releases and correct size of implant important; if repair of
radial collateral ligament does not straighten finger, best to reopen incision and repeat releases and repairs; splint—
dynamic extension splint for 6 wk
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| Devices: designs—metallic hinge; one-piece silicone flexible hinge (eg, Swanson silastic implant); 2-piece, metal and
polyethylene; pyrocarbon prosthesis
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| Silicone implants: Swanson device uses flexible spacers to maintain alignment of joint; improvements in materials (eg,
high-performance elastomer) have decreased risk for fracture; other manufacturers (eg, Sutter) have altered hinge-and-
stem design to allow more flexion of MP joint; failure—device fracture (at junction of hinge and distal stem) most
common cause; fracture may not have clinical consequence because pseudocapsule around implants may provide long-
term stabilization of MP joint; implant deformation (without fracture) also may cause recurrence of MP deformation;
other complications—silicone synovitis may cause erosions of proximal phalanx (location of implant affects risk)
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| Pyrocarbon prosthesis: pyrolytic carbon coating over graphite substrate; stable bone–implant interface; biocompatible
material resistant to wear (no risk for particulate synovitis); ball-and-socket design; commonly used for management of
posttraumatic osteoarthritis (OA) of MP and interphalangeal (IP) joints; advantages—requires minimal removal of
bone; allows for preservation of collateral ligaments and soft tissue; may improve mechanics and long-term performance
(compared to other implants); disadvantages—technically demanding; less stable (ball-and-socket design allows
more mobility); less encapsulation increases risk for recurrence of deformity; not appropriate for many patients;
complications—dislocations; fractures; recurrent or new ulnar deviation and flexion deformities
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| Long-term outcomes: silicone implants—14-yr follow-up showed 63% of implants fractured, and 22% of patients had
recurrence of severe deformity; only 27% of patients pain-free at 14 yr; pyrocarbon devices—little data on long-term
outcomes
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| Patient selection: condition of associated ligaments and soft tissues, activity level, and age of patient affect choice of implant;
young patients with posttraumatic arthritis or primary OA of single joint may benefit from pyrocarbon device; patients
should have stable reduced joints with good alignment with wrist; most patients with RA (especially late-stage
disease) require stability of silicone implant
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| ASSESSMENT OF PATIENTS WITH WORK-RELATED UPPER EXTREMITY DISORDER s—Robin R. Richards,
MD, Professor, Department of Surgery, University of Toronto, Faculty of Medicine, and Surgeon-in-Chief, Sunnybrook
and Women’s College Health Sciences Center, Toronto
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| Work-related injuries: back pain most common; upper extremity (particularly shoulder) injuries second most common;
other upper extremity injuries include arthropathies of elbow, wrist, or thumb, rotator cuff tendonopathy, epicondylitis,
compression neuropathies, spondylosis with radiculopathy, and soft tissue disorders (eg, myofascial pain,
ganglion)
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| Assessment: history; physical examination; imaging; differential diagnosis; diagnosis; relevance to work—identify associated
activities (causative or exacerbating); assess patient’s ability to return to work activities
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| Diagnosis: often patients have received multiple diagnoses from multiple clinicians; reassessment (including history, physical
examination, and imaging) generally required; psychologic effect of work-related injury may complicate diagnosis;
imaging—soft-tissue imaging (eg, magnetic resonance imaging; computed tomography; US) helpful; x-rays often insufficient;
causation—role of clinician to document nature of symptoms, arrive at diagnosis, and comment on physical limitations
and associated impact on work; determining causative factor, generally outside clinician’s scope of practice
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| Treatment: identify and discuss options with patient; assess prognosis; determine role of surgery (if any); define goals of
treatment (usually reduction in symptoms and improvement in function, rather than return to normal function);
outcome—varies by patient; ongoing assessment important (eg, range of motion, strength)
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Suggested Reading
Beris AE et al: Anatomic variations of the median nerve in carpal tunnel release. Clin Anat Jun 19, 2008 [Epub ahead of
print]; Burgess SD et al: Results of revision metacarpophalangeal joint surgery in rheumatoid patients following previous
silicone arthroplasty. J Hand Surg [Am] 32:1506, 2007; De Santolo et al: Stabilization of finger ulnar deviation in
rheumatoid arthritis: extensor indicis proprius tenodesis. J Hand Surg [Am] 33:450, 2008; Kumar A et al: The “biro
test” for autonomic dysfunction in carpal tunnel syndrome. J Hand Surg Eur Vol 33:355, 2008; Luria S et al: Endoscopic
revision of carpal tunnel release. Plast Reconstr Surg 121:2029, 2008; Mandl LA et al: Could preoperative preferences
and expectations influence surgical decision making? Rheumatoid arthritis patients contemplating metacarpophalangeal
joint arthroplasty. Plast Reconstr Surg 121:175, 2008; Massy-Westropp N et al: Post-operative therapy for metacarpophalangeal
arthroplasty. Cochrane Database Syst Rev 1:CD003522, 2008; Parker WL et al: Preliminary results of
nonconstrained pyrolytic carbon arthroplasty for metacarpophalangeal joint arthritis. J Hand Surg [Am] 32:1496, 2007;
Parkkila T et al: Osteolysis after Sutter metacarpophalangeal arthroplasty: a prospective study of 282 implants followed
up for 5.7 years. Scand J Plast Reconstr Surg Hand Surg 40:297, 2006; Scholten RJ et al: Surgical treatment options for
carpal tunnel syndrome. Cochrane Database Syst Rev 4:CD003905, 2007; Smidt MH, Visser LH: Carpal tunnel syndrome:
Clinical and sonographic follow-up after surgery. Muscle Nerve Jun 6, 2008 [Epub ahead of print]; Szczechowicz
J et al: Restoration of hand function and ability to perform activities of daily living following surgery for carpal tunnel
syndrome. Ortop Traumatol Rehabil 10:151, 2008.
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