Urgent surgical drainage guided by infection type. Flexor tenosynovitis is an emergency. Deep spaces need an anatomical approach. Herpetic whitlow mimics felon — never incise a viral lesion.
- KANAVEL'S 4 SIGNS of flexor tenosynovitis: (1) fusiform digit swelling, (2) flexed resting posture, (3) pain on passive extension, (4) tenderness along the flexor sheath — all four mean emergency theatre
- HERPETIC WHITLOW (HSV) mimics felon: DO NOT INCISE — aciclovir only; incision risks secondary bacterial superinfection and viral spread
- Deep space anatomy: thenar space (radial), midpalmar space (ulnar), Parona's space (proximal forearm deep to FDP) — each needs its own drainage approach
- Human bite ('fight bite') over the MCPJ harbours Eikenella corrodens — examine in extension, give IV amoxicillin-clavulanate, and explore the joint
- “Kanavel sign 3 (pain on passive extension) is the most sensitive and specific — an exam favourite
- “Thumb FTS communicates with the radial bursa; small finger FTS with the ulnar bursa — both involved is a horseshoe abscess
- “Parona's space infection presents as volar forearm swelling and may decompress into the carpal tunnel — watch for acute carpal tunnel syndrome
- “After FTS drainage, expect 20-30% residual stiffness even with prompt treatment — counsel patients pre-operatively
When & Why
Hand infections are surgical emergencies when they involve a closed space — the flexor tendon sheath, a deep palmar space, the fingertip pulp, or a joint. The decision to operate is driven by the infection type, how much time has elapsed, and the organism risk. The most important single principle: pyogenic flexor tenosynovitis (FTS) with Kanavel's signs is a "to theatre now" diagnosis — delay destroys tendon.
Indications for surgical drainage by infection type - Flexor tenosynovitis — emergency. All four Kanavel signs present means immediate theatre; any three signs with systemic sepsis means emergency theatre; failure of a 12-24 hour IV antibiotic trial (the Neviaser approach) means theatre; an immunocompromised patient with any two signs means theatre.
- A trial of IV antibiotics (controversial, select cases only). Very early presentation (less than 24 hours), mild, two to three signs only, a reliable admitted patient under close observation — and you proceed to theatre if there is no improvement within 12-24 hours.
- Deep space infections. Fluctuant swelling with systemic signs, or failure of IV antibiotics at 24-48 hours. Thenar space: swelling, limited thumb abduction, pain in the first web space. Midpalmar space: loss of the normal palmar concavity, pain on middle and ring finger movement.
- Paronychia. Simple acute: incise and drain when fluctuant; subungual spread requires partial nail plate removal. Chronic paronychia: only surgical (nail fold marsupialisation) after three or more months of failed conservative treatment — the underlying cause is often Candida.
- Felon. All felons with tense pulp require surgical drainage — untreated, the pulp develops vascular compromise and distal phalanx osteomyelitis.
- Web space (collar-stud) abscess. Both dorsal and palmar components require drainage — a collar-stud abscess tracks through the web space, and draining only one component leads to recurrence. The critical distinction — herpetic whitlow is NOT a felon. Herpetic whitlow (HSV-1 or HSV-2) presents with grouped vesicles, a viral prodrome, and typically a healthcare worker or child. A felon is bacterial, with a tense pulp and no vesicles. If there is any doubt, a Tzanck smear or PCR confirms HSV. Never incise suspected herpetic whitlow — see the safety alert under The Operation.
A laceration over the MCPJ from an opponent's tooth harbours Eikenella corrodens plus anaerobes. Examine the joint in EXTENSION — the injury is deeper than it looks in flexion. Eikenella is resistant to first-generation cephalosporins: use IV amoxicillin-clavulanate and explore the MCP joint.
Cat or dog bites seed Pasteurella multocida plus S. aureus. First-line cover is amoxicillin-clavulanate; doxycycline is the penicillin-allergy alternative. Assess tetanus and rabies risk in endemic regions.
Fish-tank or water exposure seeds Vibrio vulnificus and Aeromonas hydrophila — these can be rapidly progressive. Use ciprofloxacin plus doxycycline, and have a low threshold for surgical debridement.
Setup. Supine, arm table, upper-arm tourniquet, regional (axillary/supraclavicular) or general anaesthetic. Elevate the hand throughout. Loupe magnification protects the digital neurovascular bundles. Send pus for culture and sensitivity (including fungal for chronic paronychia) before giving antibiotics where possible, but never delay drainage of FTS for imaging.
The Operation
The goal is to decompress the infected closed space, remove necrotic tissue, and preserve the structures that run through it — above all the flexor tendons, the A2 and A4 pulleys, and the digital neurovascular bundles. The exposure is dictated by which space is infected. The sequence below works through the anatomy first (the exposure you must know for every case), then the specific technique for each infection type.
Operative sequence — anatomy first, then drainage by infection type
- Supine, arm table, upper-arm tourniquet, hand elevated, loupes on.
- Re-confirm the diagnosis at the bedside: for suspected FTS, elicit all four Kanavel signs; for a deep space, mark the point of maximal fluctuance.
- X-ray the hand to exclude a foreign body, gas in the tissues, or early osteomyelitis of the distal phalanx (felon). Do not delay drainage of FTS for advanced imaging.
- The digital flexor sheath runs from the A1 pulley (MCPJ volar plate level) to the FDP insertion on the distal phalanx, enclosing FDS and FDP.
- Annular pulleys A1-A5 and cruciate pulleys C1-C3 hold the tendons against bone. A2 (proximal phalanx) and A4 (middle phalanx) are the biomechanically critical pulleys — preserve them during any sheath opening, or the tendon bowstrings.
- Bursal communications: the radial bursa continues the FPL sheath proximally; the ulnar bursa continues the small finger sheath proximally. The two bursae communicate via Parona's space in roughly half to two-thirds of people — so infection can track from thumb to small finger and back as a horseshoe abscess.
- Thenar space — radial palm, deep to the thenar muscles. Bounded by the 3rd metacarpal (medial), the oblique head of adductor pollicis (floor), the thenar muscles (radial/superficial); communicates with the first web space.
- Midpalmar space — central/ulnar palm, deep to the long flexor tendons. Bounded by the 3rd metacarpal (radial), hypothenar fascia (ulnar), palmar fascia (superficial), and metacarpal periosteum/interossei (floor); contains the lumbricals to ring and small fingers.
- Parona's space — the retrotendinous space of the distal forearm, deep to FDP and proximal to pronator quadratus, bounded by FCR (radial) and FCU (ulnar). The third deep space, and the bridge of the horseshoe abscess. It may decompress into the carpal tunnel — watch for acute carpal tunnel syndrome.
- Paired digital neurovascular bundles run along the volar-lateral borders of each digit, volar to the mid-axial line; the proper digital nerve lies volar to its artery.
- Mid-lateral (mid-axial) incision — at the junction of dorsal and volar skin (the line joining the dorsal ends of the flexion creases); it stays dorsal to the neurovascular bundle and protects it. The safest digital incision.
- Brunner zigzag incision — volar, with apices at the flexion creases; excellent exposure, but the flaps overlie the bundles, so apices must not cross beyond the mid-axial line.
- Felon incisions — avoid the fish-mouth and transverse incisions (unstable pulp, digital nerve injury); use a high lateral (mid-axial) incision on the non-contact border.
- Thenar motor branch (recurrent branch of median nerve) — at risk with a volar approach to the thenar space; prefer the first web space.
Proximal window: transverse incision over the A1 pulley at the MCPJ flexion crease; identify the sheath — milky fluid under pressure confirms the diagnosis; insert a flexible catheter (8Fr feeding tube) proximally. Distal window: mid-lateral or small volar incision at the DIP crease; open the sheath at the A4/A5 level distally; allow the turbid fluid to drain. Irrigate: 500-1000 mL of normal saline through the proximal catheter until the effluent is clear; send sheath fluid for culture. Continuous post-operative infusion at 10 mL/hr for 24-48 hours via the proximal catheter. Preserve A2 and A4, do not over-distend the sheath, and look again at 48 hours.
- Brunner zigzag incisions along the whole volar digit and into the palm, OR bilateral mid-lateral incisions for an isolated digit.
- Open the digital sheath completely and debride necrotic tendon and sheath.
- Preserve every viable pulley — A2 and A4 are mandatory.
- Leave wounds open or loosely approximated over drains; return to theatre at 48 hours for a second look if contaminated.
Acute simple paronychia: elevate the nail fold with a probe, incise and drain along the nail fold margin; if there is subungual spread, remove the proximal quarter of the nail plate; drain the pus and pack loosely with ribbon gauze. Chronic paronychia (marsupialisation): excise a crescent of nail fold skin (3-4 mm) — this removes the chronically infected fold; do NOT remove the nail plate (heal over the exposed nail bed); send nail fold tissue for histology and culture including fungal; dry dressing, and an antifungal if Candida is confirmed.
- Position on the non-dominant aspect of the digit: ulnar side of index/middle/ring, radial side of small finger, ulnar side of thumb.
- A 1 cm incision from the DIP crease to 5 mm proximal to the free nail margin, curving at the tip (J-shape).
- Drain the pus and break down the fibrous septa with a blunt probe — there are multiple loculations.
- Preserve the digital nerve: blunt dissection only near the volar pulp. Pack loosely with ribbon gauze. Avoid the fish-mouth incision.
- Volar: transverse incision at the web space parallel to the natatory ligament (distal palmar crease level).
- Dorsal: longitudinal incision in the web space between the metacarpal heads.
- Communicate the two incisions by blunt dissection through the web space, drain both components, and loosely pack both ends. Draining only one component leaves the collar-stud abscess and guarantees recurrence.
- Dorsal or volar incision along the first web space, staying superficial to adductor pollicis and avoiding the thenar motor branch of the median nerve (a volar approach puts it at risk).
- Blunt dissection into the thenar space; irrigate and place a loose drain.
- Transverse incision at the distal (or proximal) palmar crease, between the ring and small finger rays.
- Deep dissection between the flexor tendons; enter the midpalmar space bluntly, taking care to avoid the common digital nerves and the superficial palmar arch.
- Drain, send pus for culture, irrigate, and loosely pack. Look again at 48 hours.
- Volar forearm incision between FCR and FCU; decompress the retrotendinous space deep to FDP.
- If there is any median nerve compromise, release the carpal tunnel at the same sitting.
- In a horseshoe abscess, drain all three spaces and both involved sheaths simultaneously — thumb sheath, Parona's space, and small finger sheath.
- Leave infected wounds open or loosely packed with ribbon gauze — primary closure of an infected space recurs.
- Loose approximation of clean wounds over a drain where appropriate; release the tourniquet and check perfusion.
- Apply a bulky soft dressing with the hand elevated above the heart; splint the hand in a safe position (wrist extended, MCPs flexed, IPs extended).
- Book the second look at 48 hours for all FTS and severe deep space infections.
A fingertip with grouped vesicles, a viral prodrome, and an occupational HSV exposure is herpetic whitlow, not a felon. Incising it risks secondary bacterial superinfection, viral spread, and prolonged morbidity. Treat with aciclovir (400 mg tds orally for 7-10 days; IV aciclovir if severe or immunocompromised), confirm with Tzanck smear or PCR, and reserve surgical drainage for the rare case of clear secondary bacterial infection. If you are about to drain a "felon" and see vesicles — stop.
For pyogenic flexor tenosynovitis, the timing decides the technique. An early presentation (under 48 hours), non-necrotic, is managed with closed catheter irrigation (Neviaser) — proximal A1 window, distal DIP counter-incision, 500-1000 mL saline, and continuous infusion for 24-48 hours. A late presentation (over 48 hours), necrotic tendon, or failed closed irrigation converts to open Bunnell drainage with full sheath debridement. Both require a second look at 48 hours.
Whatever the drainage, identify and protect the A2 and A4 pulleys; losing them causes bowstringing and staged reconstruction. In a deep space infection, always ask whether a second space is involved — thenar and midpalmar communicate through the web spaces, and Parona's space links both bursae. A horseshoe abscess needs all three spaces drained at one sitting.
Aftercare & Complications
Post-operative protocol - Immediate (0-48 hours). Elevate the hand above heart level to reduce oedema and pain; wound check at 24-48 hours to assess drainage and wound condition; continue IV antibiotics for 48-72 hours then step down to oral when afebrile and improving; for closed FTS irrigation continue the infusion for 24-48 hours then remove the catheter; begin gentle finger range of motion as comfort allows.
- Rehabilitation. FTS: commence hand therapy within 48-72 hours — passive then active digit ROM to prevent tendon adhesion, oedema management (compression, elevation, retrograde massage), and progress to strengthening at 4-6 weeks when the infection has resolved. Deep space: digit and wrist ROM within 48 hours, hand therapy at 1 week. Paronychia and felon: daily dressing changes, warm saline soaks twice daily, self-mobilisation.
- Follow-up. 48 hours: second-look for all FTS and severe deep space infections. 1 week: wound review, oral antibiotic continuation assessment. 3 weeks: ROM and hand therapy review. 3-6 months: assess for tenolysis in FTS cases with persistent stiffness. Empirical antibiotics by organism and mechanism
- Likely organisms
- S. aureus (MSSA), streptococci
- First-line IV
- Flucloxacillin 2g q6h IV (or cefazolin)
- Oral step-down
- Flucloxacillin 500mg qid or cephalexin 500mg qid for 7-10 days
- Likely organisms
- MRSA, Pseudomonas
- First-line IV
- Vancomycin + piperacillin-tazobactam
- Oral step-down
- Trimethoprim-sulfamethoxazole or doxycycline (MRSA) per sensitivities
- Likely organisms
- Eikenella corrodens, anaerobes, oral flora
- First-line IV
- Amoxicillin-clavulanate 1.2g q8h IV
- Oral step-down
- Amoxicillin-clavulanate 625mg tds for 7-10 days
- Likely organisms
- Pasteurella multocida, S. aureus
- First-line IV
- Amoxicillin-clavulanate
- Oral step-down
- Amoxicillin-clavulanate or doxycycline (penicillin allergy)
- Likely organisms
- Vibrio vulnificus, Aeromonas hydrophila
- First-line IV
- Ciprofloxacin + doxycycline
- Oral step-down
- Ciprofloxacin 500mg bd for 10-14 days
- Likely organisms
- HSV-1 or HSV-2
- First-line IV
- Aciclovir 5mg/kg q8h IV (severe/immunocompromised)
- Oral step-down
- Aciclovir 400mg tds for 7-10 days. DO NOT INCISE
Complications
- Incidence
- 20-30% (FTS)
- Key features
- Reduced digit ROM, poor grip. Worse with delayed drainage (over 48 hr), diabetes, IVDU
- Management
- Hand therapy 6-12 weeks. Staged tenolysis at 3-6 months if significant PIP stiffness persists
- Incidence
- 5-15% (delayed FTS)
- Key features
- Failed drainage, necrotic tendon visible at second look. Digit functionless
- Management
- Debridement of necrotic tendon. Staged silicone rod then tendon graft at 3-6 months
- Incidence
- 10-15%
- Key features
- Incomplete drainage, inadequate antibiotic, resistant organism (MRSA), immunocompromise
- Management
- Re-culture, escalate antibiotics, repeat washout. Exclude osteomyelitis (MRI of distal phalanx for felon)
- Incidence
- 5-10% (felon)
- Key features
- Untreated or late felon, bony destruction on X-ray, chronic non-healing wound
- Management
- 6-week IV antibiotics, surgical debridement of bone, amputation if non-viable
- Incidence
- Rare
- Key features
- Painful Tinel sign at the incision site, numbness in the digital nerve distribution
- Management
- Desensitisation therapy. Neuroma excision plus burial if refractory (over 6 months)
- Incidence
- Uncommon
- Key features
- Thumb FTS spreading via the radial bursa to Parona's space, the ulnar bursa, and the small finger FTS
- Management
- Drain all involved spaces simultaneously: thumb sheath plus Parona's space plus small finger sheath
The single most important factor determining outcome in flexor tenosynovitis is time to drainage. Prompt drainage within 6-24 hours preserves tendon function with 20-30% residual stiffness; delayed drainage beyond 48 hours markedly worsens outcome with up to 50-70% poor function and risk of tendon necrosis requiring staged reconstruction. Counsel every patient about these outcomes pre-operatively.
Viva & Exam Focus
KANAVELKANAVEL — the four signs of flexor tenosynovitis
FISTFIST — organisms by mechanism of injury
Hook:Add Vibrio or Aeromonas for aquatic injuries (fish tank, water exposure) — ciprofloxacin plus doxycycline. S. aureus remains the commonest organism across all hand infections.
Clinical Decision Scenarios
Practise clinical reasoning and management decisions out loud
“A 28-year-old man presents with a 2-day history of a swollen, painful right ring finger. On examination the entire digit is uniformly swollen, held in a flexed posture, and exquisitely tender on the volar surface. He is afebrile. Describe your assessment and management.”
“A 45-year-old labourer presents with 3 days of increasing pain and swelling in the palm. Examination shows loss of the normal palmar concavity, severe pain on attempted movement of the ring and small fingers, and a mildly raised temperature. The thumb and index are unaffected. Where is the infection and how do you drain it?”
“A 32-year-old nurse presents with 5 days of pain, swelling, and erythema around the nail fold of her right index finger. There are small grouped vesicular lesions visible. She thinks she recently treated a patient with oral herpes. How do you manage her?”
Kanavel's 4 signs (FTS emergency)
- 1. Fusiform (uniform) swelling of the entire digit
- 2. Semiflexed resting posture of the digit
- 3. Pain on passive extension (most sensitive and specific — exam favourite)
- 4. Tenderness along the entire volar flexor sheath
- All four signs mean emergency drainage within 6 hours to preserve tendon function
FTS drainage techniques
- Early (under 48 hr): closed catheter (Neviaser) — proximal window at A1 plus distal window at the DIP crease
- Irrigate 500-1000 mL saline until clear, then continuous infusion at 10 mL/hr for 24-48 hr
- Preserve A2 and A4 pulleys — loss causes bowstringing requiring reconstruction
- Late (over 48 hr) or failed: open Bunnell — Brunner zigzag or bilateral mid-lateral incisions
- Second-look at 48 hours is mandatory for all FTS cases
Deep space anatomy
- Thenar space: radial palm, deep to thenar muscles; drain via the first web space (preserve the thenar motor branch)
- Midpalmar space: ulnar/central palm, beneath the flexors to ring and small; drain via the distal palmar crease
- Parona's space: retrotendinous distal forearm (deep to FDP, proximal to PQ); the third space of a horseshoe abscess
- Horseshoe abscess: the thumb radial bursa communicates via Parona's space with the ulnar bursa (small finger) in roughly half to two-thirds of people
- Watch for acute carpal tunnel syndrome with a Parona's space infection
Organisms by mechanism (FIST)
- Fight bite (human): Eikenella corrodens plus anaerobes — amoxicillin-clavulanate IV
- IV drug user: MRSA, Pseudomonas — vancomycin plus pip-tazo empirically
- Soil/farm: Clostridium, gram-negatives — penicillin plus metronidazole plus debridement
- Tooth/claw (animal): Pasteurella multocida (cat/dog) — amoxicillin-clavulanate
- Aquatic (fish tank, water): Vibrio, Aeromonas — ciprofloxacin plus doxycycline
- S. aureus: the commonest organism overall — empirical flucloxacillin or cefazolin
Specific infection techniques
- Felon: J-incision on the non-dominant side of the fingertip; break the septa bluntly; AVOID the fish-mouth incision
- Acute paronychia: elevate the nail fold, incise and drain; if subungual spread, remove the proximal quarter of the nail plate
- Chronic paronychia: marsupialise the nail fold (crescent excision 3-4 mm); antifungal if Candida
- Web space (collar-stud): MUST drain BOTH dorsal and volar components — a single approach recurs
- Thenar space: dorsal first web space approach to protect the thenar motor branch of the median nerve
Critical distinctions
- Herpetic whitlow (HSV): grouped vesicles, viral prodrome, healthcare worker — DO NOT INCISE — aciclovir
- Felon (bacterial): single tense pulp abscess, no vesicles, progressive — J-incision required
- Fight bite: examine the MCPJ in EXTENSION not flexion — the injury is deeper than it looks in flexion
- Eikenella corrodens: resistant to first-generation cephalosporins (cefazolin) — use amoxicillin-clavulanate
- Chronic paronychia: Candida-driven, NOT bacterial FTS — surgery is marsupialisation, NOT drainage
Complications
- FTS stiffness: 20-30% with prompt drainage, 50-70% with delay over 48 hr — hand therapy is critical
- Tendon necrosis: debridement plus staged silicone rod then tendon graft at 3-6 months
- Osteomyelitis (felon): MRI of the distal phalanx; 6-week IV antibiotics plus debridement or amputation
- Horseshoe abscess spread: drain ALL three spaces simultaneously (thumb sheath plus Parona's plus small finger sheath)
- Thenar motor branch injury: thenar atrophy and loss of opposition — avoid with the correct first web space approach
Background & Evidence
Epidemiology. The subcutaneous tissue is the most common site and trauma the most common mechanism of hand infection overall. S. aureus and streptococci remain the commonest pathogens, with MRSA now prevalent in many communities — empirical MRSA cover is warranted for IVDU, healthcare exposure, prior MRSA, and failed therapy, and routinely where local prevalence is high. Diabetes, immunosuppression, steroid use, and IV drug use predispose to infection and worsen outcomes. Guidelines, registries & global practice. Hand infection management is governed by general antimicrobial-stewardship and surgical-emergency principles rather than a single arthroplasty-style registry. Practice is broadly consistent across major training systems, with differences driven mainly by local MRSA prevalence and antibiotic formularies. - Diagnosis (universal): Kanavel's four signs remain the global clinical standard for pyogenic flexor tenosynovitis across advanced orthopaedic practice and DNB/MS curricula. Pain on passive extension is the most consistently cited single sign.
- Empirical antibiotics — regional variation: anti-staphylococcal cover (flucloxacillin or a first-generation cephalosporin) is standard first-line. Routine empirical MRSA cover (e.g. vancomycin) is recommended where community-acquired MRSA prevalence is high (parts of the US per IDSA skin-and-soft-tissue guidance) but reserved for risk factors in lower-prevalence settings (UK, Australia, much of Europe).
- Bite wounds (consistent globally): amoxicillin-clavulanate is the first-line agent endorsed across UK (NICE/BNF), US and Australasian guidance for human and animal bites; doxycycline plus metronidazole, or a fluoroquinolone plus an anti-anaerobe, are the usual penicillin-allergy alternatives. Tetanus and rabies risk assessment is mandatory for animal bites in endemic regions.
- Surgical principle (universal): all but the earliest pyogenic flexor tenosynovitis requires drainage; closed catheter irrigation is preferred for early non-necrotic cases and open drainage for late or necrotic disease, with a low threshold for second-look. This is consistent across hand-society teaching (ASSH, BSSH, FESSH).
- Resource-setting variation: where theatre access or microbiology is limited, earlier empirical broad-spectrum cover and bedside incision/drainage of superficial collections are more common; the underlying surgical anatomy and drainage approaches are unchanged. Pang prognostic classification (surgical decision-making). The Pang classification (2007, 75 patients) stratifies pyogenic flexor tenosynovitis by intra-operative findings and predicts both amputation risk and recovery of total active motion (TAM):
- Intra-operative findings
- No subcutaneous purulence, no digital ischaemia
- Amputation risk
- 0%
- Mean total active motion
- 80%
- Intra-operative findings
- Subcutaneous purulence, no ischaemia
- Amputation risk
- 8%
- Mean total active motion
- 72%
- Intra-operative findings
- Extensive purulence plus digital ischaemia
- Amputation risk
- 59%
- Mean total active motion
- 49%
References
- Kanavel AB. Infections of the Hand: A Guide to the Surgical Treatment of Acute and Chronic Suppurative Processes in the Fingers, Hand, and Forearm. Philadelphia: Lea & Febiger, 1912. [Original description of the four cardinal signs of flexor tenosynovitis — clinical gold standard] 2. Pang HN, Teoh LC, Yam AK, Lee JY, Puhaindran ME, Tan AB. Factors affecting the prognosis of pyogenic flexor tenosynovitis. J Bone Joint Surg Am 2007;89(8):1742-8. PMID: 17671013. doi:10.2106/JBJS.F.01356. [Three-tier prognostic classification of FTS linking subcutaneous purulence and digital ischaemia to amputation rate and total active motion] 3. Neviaser RJ. Closed tendon sheath irrigation for pyogenic flexor tenosynovitis. J Hand Surg Am 1978;3(5):462-6. PMID: 556478. doi:10.1016/s0363-5023(78)80141-5. [Original description of closed continuous catheter irrigation; 18 of 20 patients regained full motion by one week] 4. McDonald LS, Bavaro MF, Hofmeister EP, Kroonen LT. Hand infections. J Hand Surg Am 2011;36(8):1403-12. PMID: 21816297. doi:10.1016/j.jhsa.2011.05.035. [Comprehensive review of hand infection diagnosis, organisms (including MRSA), and surgical treatment] 5. Draeger RW, Bynum DK. Flexor tendon sheath infections of the hand. J Am Acad Orthop Surg 2012;20(6):373-82. PMID: 22661567. doi:10.5435/JAAOS-20-06-373. [Contemporary review of FTS management including closed vs open techniques and expected residual stiffness] 6. Osterman M, Draeger R, Stern P. Acute hand infections. J Hand Surg Am 2014;39(8):1628-35. PMID: 25070032. doi:10.1016/j.jhsa.2014.03.031. [Modern overview of all acute hand infection types with emphasis on resistant organisms and timely treatment] 7. Goldstein EJ, Citron DM, Hudspeth M, Hunt Gerardo S, Merriam CV. In vitro activity of Bay 12-8039, a new 8-methoxyquinolone, compared with 11 other oral antimicrobials against 390 aerobic and anaerobic bacteria isolated from human and animal bite wound infections. Antimicrob Agents Chemother 1997;41(7):1552-7. PMID: 9210683. doi:10.1128/AAC.41.7.1552. [Microbiological basis for amoxicillin-clavulanate as empirical cover for bite wounds, including Eikenella and Pasteurella] 8. Goldstein EJ, Citron DM. Comparative activities of cefuroxime, amoxicillin-clavulanic acid, ciprofloxacin, enoxacin, and ofloxacin against aerobic and anaerobic bacteria isolated from bite wounds. Antimicrob Agents Chemother 1988;32(8):1143-8. PMID: 3190202. doi:10.1128/AAC.32.8.1143. [Susceptibility data for bite-wound flora including Eikenella corrodens and Pasteurella multocida]
Factors affecting the prognosis of pyogenic flexor tenosynovitis
- 75 patients over 6 years stratified into a three-tier intra-operative classification predicting outcome
- Group I (no purulence, no ischaemia): 0% amputation, mean 80% return of total active motion
- Group II (subcutaneous purulence, no ischaemia): 8% amputation, mean 72% total active motion
- Group III (extensive purulence plus digital ischaemia): 59% amputation, mean 49% total active motion
- Five poor-prognosis risk factors: age over 43, diabetes/PVD/renal failure, subcutaneous purulence, digital ischaemia, polymicrobial infection
Closed tendon sheath irrigation for pyogenic flexor tenosynovitis
- 20 patients treated with through-and-through saline catheter irrigation and a small Penrose drain for 48 hours
- 18 of 20 patients regained complete active and passive motion by one week post-operatively
- All patients discharged within 4 days, with minimal residual tendon adherence
- Established proximal-window-and-distal-counter-incision closed irrigation as a sheath-preserving technique
Flexor tendon sheath infections of the hand
- Kanavel's cardinal signs are central to differentiating FTS from mimics
- All but the earliest cases require IV antibiotics plus surgical drainage (open or closed irrigation)
- Even otherwise healthy patients can expect some residual digital stiffness after sheath infection
- Late presentation or significant comorbidity predicts poorer outcomes including severe stiffness or amputation
Acute hand infections
- S. aureus and streptococci remain the commonest pathogens; MRSA is now prevalent and warrants empirical cover where local prevalence is high
- Subcutaneous tissue is the most common site and trauma the most common mechanism of hand infection
- Immunocompromise, IV drug use, diabetes and steroid use predispose to infection and worsen outcomes
- Delayed or missed diagnosis risks stiffness, contracture and amputation
In vitro activity of 12 oral antimicrobials against 390 aerobic and anaerobic bacteria from human and animal bite wounds
- Tested 250 aerobic and 140 anaerobic isolates recently cultured from human and animal bite wounds
- Amoxicillin-clavulanate retained activity across the aerobic and anaerobic bite-wound flora, including Eikenella, Pasteurella and Fusobacterium
- Fluoroquinolones were active against aerobes but less reliable against anaerobes (peptostreptococci, Prevotella, Porphyromonas)
- Provides the microbiological basis for amoxicillin-clavulanate as first-line empirical cover for bite wounds