Scaphoid Fractures Management PDF

Scaphoid fractures management Mr Ghandi Almanasir MD, MRCSEd Orthopeadic senior specialist Royal medical services What to do ? Outlines Epidemiology Relevant anatomy Relevant biomechanics Diagnosis: History, Physical examination and radiology Classification Treatment option...

Scaphoid fractures management Mr Ghandi Almanasir MD, MRCSEd Orthopeadic senior specialist Royal medical services What to do ? Outlines Epidemiology Relevant anatomy Relevant biomechanics Diagnosis: History, Physical examination and radiology Classification Treatment options Complications Dealing with the complications Rule of 70’s for scaphoid 70% of all carpal fractures occur at scaphoid. 70% of blood supply is by the dorsal branch of the radial artery. 70% of fractures occur at the waist of scaphoid. 70% of the scaphoid fractures unite. 70 % of the bone covered with cartilage 70 % of scaphoid fractures patients are males Relevant Anatomy Articulation Wrist intrinsic ligaments SL is just distal to Lister’s tubercle Relevant Anatomy Boat-shaped bone (skaphos), navicular (Navis) Irregular twisted peanut Blood supply Retrograde No anastomosis Relevant Anatomy Volar tilt Lateral IntraScaphoid Angle (LISA) Sagittal CT as the angle between the perpendicular lines on the distal and proximal articular surfaces of the scaphoid. (24-30)° < 35° Biomechanics Scaphoid links the proximal and distal rows, it affects both Scaphoid flexes with wrist flexion & radial deviation Scaphoid extends with wrist extension & ulnar deviation difficult to immobilize Biomechanics Scaphoid is bony block to dorsiflexion , fracture during fall on outstretched hand. With scaphoid waste fracture: distal scaphoid tends to flex proximal scaphoid tends to extend Angulation occurs at fracture site, humpback deformity Mechanism of injury Two different mechanisms 1. Compression injury : usually results in non displaced fx 2. Hyperextension bending injury : usually results in displaced fx 16 Compression injury 17 Hyperextension bending injury Fall on outstretched hand Forced dorsiflexion of wrist(beyond 95degree) Compression occurs dorsally and tension on palmar surface of wrist. Bending forces applied to waist and distal pole of scaphoid as proximal pole is tightly held between capitate,dorsal lip of radius and taut palmar capsule. Leads to fracture scaphoid most commonly waist Diagnosis A strong index of suspicion is the key to early diagnosis The diagnosis should be based on : 1. History 2. Clinical examination 3. Radiographic evaluation. History Occurs after a fall on an outstretched hand, athletic injury, or Motor Vehicle accident Usually happens in young adult men Pain and swelling at the radial side of the wrist Inability or difficulty in moving the involved wrist Any Associated injuries. Palpable Anatomy Proximal pole – dorsum of wrist Lister’s tubercle Sulcus (radiocarpal joint) Prominence (scapholunate joint) Move radial for proximal pole Waist of Scaphoid Dorsal : distal to rim of distal radius towards styloid Distal pole Dorsal : between EPL and ECRL Distal pole Lateral : proximal to radial artery in anatomical snuff box with wrist in neutral position. Distal pole Volar : along with FCR as it enters fibro-osseous tunnel Provocative tests Snuff box tenderness Scaphoid compression test Scaphoid tubercle tenderness Painful resisted pronation Painful attempted Scaphoid shift test Physical examination Snuff box tenderness 100% sensitivity Scaphoid tubercle tenderness 20% specific Adding Scaphoid compression test : Specificity reaches 74% Radiographic evaluation  Radiographic evaluation Wrist PA, Lateral, Oblique, Scaphoid views 45 degrees pronated and supinated oblique views 5 views increased sensitivity and specificity to almost 100% Wrist PA Wrist lateral Scaphoid view Supinated Oblique  Pronated Oblique What if radiographs are inconclusive?  Bone Scan-Scintigraphy Fast and reliable diagnostic tool 100% Sensitivity Disadvantages: Lacks specificity Little information regarding location 15% False positive Computed Tomography Scan oriented to longitudinal axis of scaphoid for hump back deformity For surgical planning & assessment of healing To diagnose additional bony injuries Disadvantages False positives in diagnosing occult fractures. MRI 2nd line test in negative radiographs Identifying fractures of other carpal bones, ligament injuries Highest sensitivity and specificity Classifications  Mayo Classification tubercle Distal articular surface Distal third Midwaist Proximal pole Russe’s classification Functional Stable ---- undisplaced Unstable ---- displaced 1 mm gap intrascaphoid angle of > 35° scaphoid fractures associated with perilunate dislocation, (DISI) comminuted fractures vertical or oblique fractures 50 Treatment Have we diagnosed it yet?  Suspected scaphoid # Xray -ve Immobilize and review in 2 weeks No signs or symptoms Still symptomatic discharge Repeat x-ray Fracture identified No fracture identified Unstable Stable MRI within 6 weeks of injury Surgery Conservative discharge No fracture identified  Conservative (Cast) contraversies:  The position of the wrist in the cast  The need to include joints other than the wrist.  The duration of the immobilization. Above elbow casts… shorter time to union the union rate is the same for below or above elbow casts. (duration not position) The current recommendation is to use a short arm thumb spica with the thumb interphalangeal joint free and mcp joints of other fingers free. The wrist is placed in radial deviation i.e. the glass holding position Long arm cast is recommended for nondisplaced proximal pole fractures.  Average time to healing by location :  Distal third fracture heals in 6-8 weeks  Middle third fracture 8-12 weeks  Proximal third fracture 12-24 weeks A 95 % union rate can be expected with this management. Prognosis is excellent in undisplaced, stable fractures if diagnosed and immobilized early  Surgery (Screw fixation) A. Herbert screw B. Herbert Whipple cannulated screw C. Acutrak screw D. Twin-Fix two-part variable screw E. AO cannulated ( 3.5 mm) Headless … cannulated …. double compression Approaches Volar approach -- is most of the time the preferred approach to limit the injury to the blood supply of the scaphoid This approach is indicated for the following injuries: -Irreducible, displaced scaphoid fractures, in the distal two thirds -Comminuted fractures Dorsal approach – will be used to address the fractures of the proximal pole 56 Volar Approach Angled skin incision The landmarks for this incision are: The scaphoid tubercle The flexor carpi radialis (FCR) tendon Retrograde screw fixation 57 Exposure of the wrist capsule The capsule is then incised obliquely from the tubercle distally towards the palmar rim of the radius proximally. Preserve as much of the palmar ligament complex. Expose the scaphoid Retract the divided radioscaphocapitate ligament to expose the scaphoid. If it is necessary to expose the proximal part of the scaphoid, divide the long radiolunate ligament, proximally as far as the palmar rim of the radius. 58 Wound closure The divided palmar ligaments (radioscaphocapitate/long radiolunate) must be repaired with fine interrupted sutures in order to prevent secondary carpal instability. Approximate the soft tissues over the scaphotrapezial joint. Test the integrity of the soft-tissue repair by passive wrist motion. Finally, the FCR tendon sheath is repaired and covered with subcutaneous tissue. 59 Proximal Pole Fractures Dorsal approach allows direct visualization of the fracture Antegrade screw fixation 61 62 Dorsal approach Indications Proximal pole fractures Complete scapholunate (SL) ligament rupture Scaphoid fractures, or complete SL ligament ruptures with concomitant distal radial fractures 63 Straight skin incision Make a straight dorsal skin incision starting over Lister’s tubercle... and extending for about 4 cm distally. 64 Identify the radial nerve Identify and preserve the dorsal superficial branch of the radial nerve, which runs in the radial skin flap of the wound. Incise the retinaculum Incise the extensor retinaculum over the extensor pollicis longus (EPL) tendon opening the distal part of the third extensor compartment 65 Retraction of the tendons EPL retracted radially The fourth extensor compartment (EDC & EIP) Retracted ulnary. Opening the capsule Make a longitudinal or inverted T-shaped incision, starting at the dorsal rim of the distal radius, extending to the dorsal intercarpal ligament. 66 Expose the scaphoid Wrist flexion SL ligament identified Wound closure Close the capsule with interrupted sutures Close the extensor retinaculum Leave EPL free 67 Post op care Immobilization with cast Duration varies according to many factors: comminution Fixation stability location cyst 6-12 weeks (till you see element of healing)  COMPLICATIONS OF SCAPHOID FRACTURES: 1. Delayed union (middle 1/3rd, 20%). 2. Malunion. 3. Non union. 4. AVN (Proximal l/3rd, 15-40%). 5. OA of radiocarpal or intercarpal joint Avascular necrosis AVN Is commonly seen it proximal pole fractures due to inadequate blood supply prevalence Is 35%. Can be detected at earliest by MRI followed by CT and plain Xrays. Seen as patchy sclerosis on X-rays. Treatment- Prolonged immobilization could be tried ? Operative revascularization if early detected or symptomatic patient. CT -Scan CT –scan is a better option than plain radiograph. Proximal pole fracture with dense sclerosis of proximal pole  MRI MR imaging has been shown to be highly sensitive for AVN as compared to plain radiograph. Decrease in the marrow signal intensity in T1 weighted images is suggestive of AVN. Non union of scaphoid A scaphoid fracture becomes a non-union when it fails to unite for any reason within 6 months of injury. Age: 2nd and 3rd decade (Common) 12% rate of non-union. Etiology:  Severity of initial injury.  Fracture pattern and location. (Proximal l/3rd and vertical oblique)  Displacement of fracture fragments > 1mm.  Associated ligamentous and carpal injury.  DISI(distal intercalated segment instabilty)  Inadequate immobilization.  Delayed treatment.  Smoking  Nonunion is expected more often if the scaphoid # is untreated for 4 or more weeks. This can result in nonunion rate of 88%. Symptoms: Wrist pain Loss of motion - especially dorsiflexion Weakness of grip. Scaphoid Nonunion Advanced Collapse (SNAC) Treatment Treatment principle: 1. Preservation of blood supply 2. Bone apposition by a graft 3. Internal fixation for fracture stability 4. Correction of carpal instability.  Following operations are done at different stages: ORIF with non vascularised bone grafting ORIF with vascularised Bone grafting Radial styloidectomy and distal pole excision Excision of proximal fragment Proximal row carpectomy Partial or total arthrodesis of wrist. ORIF with Bone grafing operations Three basic types of bone grafting: In situ inlay grafts - best for undisplaced stable non union. Interposition grafts - for displaced non union to correct angulation secondary to volar resorption. Vascularized bone grafts - most appropriate for specific circumstances like longstanding nonunion, AVN and in which conventional grafting is likely to fail. Inlay grafting The scaphoid is exposed and sclerotic bone ends are freshened and cavity is formed by removing a sclerotic bone. A corticocancellous graft from the distal radius or iliac crest is taken and shaped according to the cavity and the graft is placed. Two K-wires are passed from distal to proximal. Long arm thumb spica cast is applied for 6 weeks.  Matti & Russe procedure (Inlay grafting) Used for fracture nonunion of scaphoid that donot have associated shortening or angulation Procedure – -fracture site exposed - Sclerotic bone ends freshened - - cavity formed with high speed burr - -corticocancellous bone graft taken from iliac crest & shaped in such a way that it fit into preformed cavity - Fragments stablised with k wire Fernandez procedure (Interposition graft) Used for fracture nonunion with resorption of cortex & angulation. Due to resorption or comminution, shortening and angulation, with its convexity dorsal and radial occurs in non union fractures of scaphoid leading to “humpback” deformity The deformity includes extension of the proximal pole of the scaphoid, resulting extension of the lunate, and a form of dorsal intercalated instability pattern seen on lateral plain radiographs Procedure- Preoperatively size of graft and angular deformity calculated Bone is resected from distal and proximal fragment Flexion deformity and shortening is corrected Corticocancellous graft of proper shape and size harvested from iliac crest Graft is correctly inserted into defect and fixed with kwires. VASCULARISED BONE GRAFTS Effective method for treating -Nonunions with an avascular proximal pole -Nonunion with failed previous procedures SOURCES: Pronator quadratus pedicle graft from the distal radius Distal dorsolateral radius pedicle bone grafts based on the 1,2 intercompartmental supraretinacular artery. 1,2ICSR Presence established radiocarpal arthrosis may compromise functional outcome.  ZAIDEMBERG et al Oblique incision on dorsoradial side Scaphoid and bone graft donor site exposed On distal radial periosteum longitudnal course of ascending irrigating branch of radial artery identified  Branches of superficial branch of radial nerve identified and protected  Bone graft is harvested with longitudnal vessels at it centre Scaphoid nonunion site is exposed & sclerotic bone ends are freshen up & then fracture is reduced A 15 to 20 mm trough in scaphoid is made along it’s aixs.  Harvested bone graft is transposed to the defect in scaphoid Stablized with k wires Salvage procedures  Radial styloidectomy and distal pole excision It is done when arthritic changes involve only scaphoid fossa of radiocarpal joint. In older patients with radioscaphoid arthritis. SNAC 1 and 2 Can be done alone or in conjunction with any grafting procedure of scaphoid Proximal row carpectomy Proximal row carpectomy is used as a reconstructive procedure for posttraumatic degenerative conditions in the wrist, especially conditions involving the scaphoid and lunate. Excision of Scaphoid, lunate and triquetrum Alternative to arthrodesis. It is considered to be a satisfactory procedure in patients who have limited requirements, desire some wrist mobility, and accept the possibility of minimal persistent pain Salvage procedures Limited wrist arthrodesis Midcarpal joint degeneration. SNAC Stage 3 Total wrist arthrodesis Involvement of radiolunate joint SNAC Stage 4 Complete arthrodesis of wrist Treatment of choice for scaphoid nonunion with advanced degenerative arthritis of wrist.  Malunion Occurs when a displaced or angulated fracture is allowed to heal without anatomic reduction. resulting in a fixed humpback deformity : pain decreased of motion decreased grip strength Treatment in a young patient includes osteotomy, volar wedge bone graft, and internal fixation Once degenerative arthritis has begun ,treatment is limited to a salvage procedure such as proximal row carpectomy,intercarpal arthrodesis,or complete wrist fusion  TAKE HOME MASSEGE Scaphoid is twisted irregular bone, special x-ray views Index of suspicion, physical examination and carful evaluation Stable fracture, the glass holding position cast till radiological healing Surgery is for unstable fracture Dorsal approach for proximal pole and waist # Volar approach for distal and waist # Non union (SNAC) and AVN treated with bone graft Salvage procedures for cases associated with OA