Amputations and Osteomyelitis Review EBM 2024 PDF

Amputations and Allen J Kempf DPM, MS, FACFAS, DABPM Assistant Professor Osteomyelitis College of Podiatric Medicine and Surgery Review Des Moines University EBM 2024  Demonstrate knowledge of determining the appropriate le...

Amputations and Allen J Kempf DPM, MS, FACFAS, DABPM Assistant Professor Osteomyelitis College of Podiatric Medicine and Surgery Review Des Moines University EBM 2024  Demonstrate knowledge of determining the appropriate level of amputation involving the lower extremity/foot Objectives Identify indications, procedures, post-op care and complications of digital, foot and leg amputations  Periostitis: Inflammation of the periosteum Osteitis: Inflammation of cortex only Osteomyelitis: Inflammation of the medullary canal Sequestrum: Dead bone separated from host Definitions- bone which is floating in purulence/inflammatory cells Resnick Involucrum: New bone sheath formation around purulence/inflammatory cells Cloaca: Sinus tract or opening through the involucrum Brodie’s Abscess: Chronic abscess with surrounding bone formation/sclerosis Osteomyelitis Hematogenous More common in Acute Time: Within 2 weeks Classification- children/elderly and patients with sickle cell disease of infection Pathology: Waldvogel Long bones (metaphysis) IV drug users microorganisms, thrombosed vessels, Contiguous neutrophils Most common presentation in lower extremity, diabetics Chronic Direct Inoculation Time: May not occur Stepping on foreign body until 6 weeks Associated with vascular Pathology: Necrotic insufficiency bone Osteomyelitis Stage 1: Medullary Osteomyelitis (early Physiologic class A. Normal host Classification- hematogenous) B. Systemic Stage 2: Superficial compromise Cierny and Osteomyelitis (early B. Local compromise Mader contiguous) Stage 3: Localized C. Treatment worse than disease Osteomyelitis Stage 4: Diffuse Osteomyelitis Wagner Wound Classification System History & Physical Exam Maintain high index of suspicion in susceptible/high risk patients Acute OM: Symptoms usually occur within 2 weeks of infection Erythema, Edema, Increased temperature Pain Systemic signs of infection (fever, chills, etc.) History & Physical Exam (cont.) Chronic OM: Symptoms usually occur gradually and over time, typically > 2 weeks Edema, Erythema, pain Systemic signs less common Chronic, non-healing ulcerations Physical exam should be focused on finding source/location of infection Look for alternative sources Wound exam Probe-to-bone https://www.sharedhealthservices.com/post/osteomyelitis-in-non-healing-diabetic-foot-ulcers  Imaging Radiographs: Primary imaging modality utilized for initial evaluation Changes typically become visible around 2 weeks Can be used to rule out other differentials 50-75% of bone matrix must be lost prior to visualization on Xray CT scan: More sensitive than Xray in evaluating changes to osseous structures Used mainly to evaluate osseous https://ars.els-cdn.com/content/image/1-s2.0-S0958259210000854-gr1_lrg.jpg destruction, better able to detect bone fragment necrosis than MRI Expensive, radiation concerns Imaging (cont.) Bone scintigraphy (bone scan) Radioisotope Technetium typically utilized Binds to phosphate Increased uptake at sites with new bone formation “hot spot” on imaging Increased uptake at sites of pathology Dependent on blood flow 3- and 4-phase scans utilized for OM Sensitivity is high, specificity is lower than Xray  Imaging (cont.) MRI: Highest sensitivity (78-90%) and specificity (60-90%) in detecting OM May visualize presence of infection within 3-5 days of onset of disease Decreased signal intensity (dark) on T1, increased signal (light) on T2 Limited when hardware is present High negative predictive value i.e if negative on MRI and symptoms present for at least one week, unlikely to be OM Culture/Pathology Bone biopsy “Gold standard” of OM diagnosis Identifies pathogen and antimicrobial susceptibility Should collect 2 samples if possible, one for culture and gram stain and one for histopathology Open procedure preferred rather than percutaneous If percutaneous, perform through intact skin, not ulcer https://www.tsc-deutschland.de/wp-content/uploads/2017/08/2012-eng-bd-jamshidi.pdf Can use Jamshidi needle for specimen collection Treatment Surgical debridement(s) of infected tissues Must control infection first, function comes after resolution Antibiotic beads/spacers Delayed closure/vac-assisted closure Culture and sensitivity driven antibiotics Continued oral antibiotics Local wound care https://www.jfas.org/article/S1067-2516(09)00452-9/fulltext Indications for Lower Extremity Amputations Acute infection Chronic infection Ischemic limb Gangrene Charcot deformity Trauma Tumors Congenital abnormalities  Superior Function Better Cosmesis Benefits of Enhance Lifestyle Distal Limb Lower Energy Consumption Salvage Increased Sensory Input Better Weight-Bearing Surface Procedures Less Distortion of Body Image  Adequate blood flow Factors Control infection Glucose control Contributing Smoking cessation to Successful Attempt to achieve functional biomechanical result Limb Salvage Create a stable soft tissue envelope  “Remove all necrotic, Successful painful, or infected Malone, J. et al, Chapter 64, Vascular Diagnosis, 4th tissue.” Amputations “Must be able to fit edition, Mosby, 1993, page568 amputation stump with a functional and easily applied prosthesis.” “Blood supply at the level of the proposed amputation must be sufficient to allow primary skin healing.” Angiosomes The concept of angiosomes to predict healing potential Angiosomes: composite The angiosome concept was vascular territories providing derived from plastic surgery to blood supply to skin, nerves, evaluate healing potential of muscle, tendon, and bone flaps. Entire body is divided into 40 angiosomes. The foot is divided into 6 angiosomes Plastic and Reconstructive Surgery: June 2006 - Volume 117 - Issue 7S - p 261S-293S Angiosomes of the Foot & Lower Leg Posterior tibial artery feeds 3 angiosomes The anterior tibial artery feeds one angiosome The peroneal artery feeds two angiosomes Volume 117, Number 7S Angiosomes of the Foot and Ankle  In planning appropriate consultation for perioperative medical care, the podiatric surgeon should be aware of the evaluation of physical status completed by the anesthesiologist before surgery. Class 1: patients have no medical problems, other than the pathologic condition associated with the surgery, no diabetic patient will fit this category. Medical Class 2: patients have a stable, chronic medical problem that is well controlled such as stable diabetes. Considerations- Class 3: patients are more seriously ill, with unstable medical problems, and are more likely to need intensive, or at least close, medical ASA Classification supervision in the perioperative period. Class 4: patients are very seriously ill, perhaps at risk for septic shock, or other major cardiovascular complications and require intensive perioperative care. Class 5: patients are not expected to survive surgery or the perioperative period. The surgeon should ensure that appropriate medical consultation, clearance, and follow-up have been obtained to provide for the perioperative medical care of a diabetic patient who will undergo surgery for an infected foot. Common Amputations Digit Amputation Ray Resection Transmetatarsal Amputation Hindfoot Amputations: Chopart’s Boyd’s Pirogoff Syme’s  Digit Amputation Digit amputation is frequently performed through the base of the proximal phalanx This is left in place to maintain intrinsic muscle stability around the metatarsal phalangeal joint Resection at the proximal metaphysis allows for closure over raw cancellous bone, which is an area that is better vascularized than the cartilage of the metatarsal head Skin incisions are made with medial and lateral flaps fashioned around the base of the digit Ray Resections Ray section is defined as amputation of a digit and most, or all, of its associated metatarsal This is an excellent procedure for drainage of an acute infection It is usually performed in the presence of either abscess or osteomyelitis of a toe and its metatarsophalangeal joint Extensive necrosis of skin, soft tissue, or bone in the involved digit may necessitate ray resection to obtain adequate viable skin for closure  Transmetatarsal Amputations Technique: Parabola should be established Indications for metatarsal amputation: maintaining length from longest Gangrene of one or more toes and associated to shortest as 2, 3, 1, 4, 5 metatarsal, provided the gangrene has stabilized and does not involve the dorsal or plantar aspect (McGlamry) of the foot Osteotomy should be beveled Stabilized infection or open wound of the distal portion of the foot from dorsal-distal to proximal Extension of an infectious process to the web plantar space or plantar aspect of the foot is an indication for an open transmetatarsal amputation. (This may be closed later or be allowed to heal by second intention) This amputation maybe be performed at any level of the metatarsals, provided the insertion of the tibial and peroneal tendons are preserved Preservation of the tendon cannot be overemphasized as loss of function will result in an equinus deformity. TAL or gastrocnemius recession are adjunct procedures Hindfoot Amputations Choparts ¨ Disarticulation at talonavicular and calcaneal cuboid joint Boyd – tibial – calcaneal fusion Modified Boyd’s – utilize talus as interposition bone graft if viable Pirogoff – tibial – calcaneal fusion Calcaneus is positioned vertical to help alleviate limb length discrepancy Symes – Full ankle disarticulation Syme’s Amputation Disarticulation at ankle Advocated for alternative to BKA § Full length extremity that can be used in emergency ambulation § Boyd Amputation ú Symes with tibialcalcaneal fusion ­ Allows for more length of limb Single Stage procedure Double Stage procedure § 2nd stage is to remove malleoli and to remodel stump for prosthesis Controversy surrounds the stability of the amputation and difficulty related to prosthetic construction Case Presentation Clinical Presentation 42-year-old female who presents to PCP office 4 days after stepping on a screw with her left heel. Patient states she removed the screw at home from her foot without concern Continued to have pain, saw primary care provider for antibiotics and pain management for 10 days, returned and was given additional 10 days of antibiotics and anti-inflammatories 25 days following initial event, presented to specialist office for further evaluation secondary to pain of the left heel and was unable to walk on the foot at this time History PMH: HTN Meds: Lisinopril Allergies: Strawberry PSH: None FH: Non-contributory SH: Desk job, denies tobacco, alcohol, illicit drug use Physical Exam Gen: No acute distress, no systemic signs of infection, A&O x 3 Vascular: Pulses are palpable b/l, no edema noted to left foot, CFT < 3 sec to digits of b/l lower extremities Neuro: Light touch sensation intact b/l, protective sensation intact b/l, No focal weakness to either lower extremity Derm: Erythema to plantar aspect of left heel, no open wounds, no drainage b/l Ortho: Pain on palpation to plantar left heel and side to side squeeze of the calcaneus on the left foot. No significant findings to the right foot Imaging Diagnosis? Direct inoculation osteomyelitis Treatment Debridement Culture-guided antimicrobial therapy