TRAUMA TREATMENT
From the 9th Annual Chicago Trauma Symposium
| TIBIAL MALUNIONS: STRATEGIES —Mark C. Reilly, MD, Associate Professor, Department of Orthopaedics,
and Co-Chief, Orthopaedic Trauma Service, University of Medicine and Dentistry of New Jersey, New Jersey Medical
School, Newark
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| Causes of malunion: failure of nonoperative treatment; diaphyseal malunion; proximal and distal tibial malunions
(failure of operative treatment)
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| Long-term effects: conflicting information; some clinical studies show evidence of osteoarthritis (OA) in adjacent
joints and functional limitations; in other studies, effects absent (malunions somewhat smaller)
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| Examination: angular, rotational, and length issues; orientation of adjacent joints in space; overall mechanical axis of
limb; length—measure prone knee-to-heel height; radiographic measurement more accurate (computed tomography
[CT]); rotational deformity—visible clinically; look at axis of movement of knee joint and axis of movement of ankle
joint; CT torsional study of proximal and distal tibia useful; angular deformity—on plain x-ray, draw lines down anatomic
axis of proximal and distal tibia (intersection of lines moves away from apex of deformity as translation increases);
deformity on both anteroposterior (AP) and lateral views—single deformity, not orthogonal to either view;
determine no-angulation view by rotating tibia under fluoroscopy to identify plane in which no deformity in diaphysis;
maximal angular deformity present at opposite 90° view
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| Surgical indications: ligamentous instability on convex side of deformity; leg-length discrepancy >2 cm; inability
to place foot plantar grade on floor; unicompartmental OA; significant malrotation; significant varus or valgus deformity
at knee or ankle; medial mechanical axis shift; radiographic indications relative (not absolute) indications;
requires healthy active patient
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| Preoperative planning critical: determine—operating room logistics; site of previous incisions and surgical approach;
configuration of osteotomy; surgical devices required to correct deformity; implants needed; access to autograft
or allograft; type of osteotomy—single-plane oblique wedge osteotomy enables correction of combined
angular and rotation deformity; use Benirschke formula to calculate angle of saw to correct rotation
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| Nailing for stabilization: advantages—less surgical dissection; less soft-tissue irritation; potential earlier full weight-
bearing; disadvantages—difficult when canal obliterated by malunion; less precise correction of metadiaphyseal
malunions (stability variable); residual valgus deformity in distal tibia; indications—diaphyseal malunions (simple angular
or rotational correction); selected metaphyseal malunions; soft-tissue compromise prevents alternative approach
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| Plating for stabilization: advantages—assists correction; more precise correction of deformity; better initial stability;
versatile (for placement of osteotomy); disadvantages— more surgical dissection; potential implant irritation;
possibly longer time to full weight-bearing; indications—canal difficult to reestablish; complex angular and
rotational deformities; metadiaphyseal malunions; requires good or reconstructible soft tissues
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| External fixation: advantages—useful for complex multiplanar deformity associated with significant shortening;
minimizes need for bone grafting; provides option when joint previously infected and when poor soft tissues exclude
other techniques; useful for short-segment periarticular malunions; disadvantages—requires compliant and
tolerant patient; high maintenance; painful for patient (and “for the surgeon”); pin-tract sepsis; long duration of
treatment; technically demanding; pitfalls—poor preoperative planning; unstable fixation; improper patient selection
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| Summary: goals—restore normal limb alignment; improve patient function; decrease pain; prevent or treat OA in
adjacent joints; requires—tailoring surgery to patient, deformity, and soft tissues
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| FEMORAL NECK INJURIES: TIPS AND PEARLS —Dean G. Lorich, MD, Assistant Professor of Surgery, Weill
College of Medicine of Cornell University, and Associate Director of Orthopaedic Trauma, New York Presbyterian
Hospital/Hospital for Special Surgery, New York, NY
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| Biologic problem: displaced femoral neck fracture kinks (possibly tears) blood vessels; avascular necrosis (AVN)
does not necessarily require total hip arthroplasty (THA); head capable of vascularizing within limited time; limitations
on femoral neck healing—no periosteum (intracapsular fracture); fracturing tears nutrient vessels from lateral
and medial circumflex vessels; osteoporosis— according to study, clinical outcome unaffected by patient’s bone density
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| Open reduction and internal fixation (ORIF): for successful outcome—no AVN; healed fracture; no implant
cut-out; hip implant problem—sliding implants dial-in malunion (acceptable nowhere else in body); cannulated
screws or compression hip screw rely on sliding (shortening) of femoral neck
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| Surgical outcomes: nondisplaced fractures—healing complications minimal; quality of life regained; displaced
fractures—high rate of healing complications; decreased quality of life even after healing; ability to walk without
cane—greater in total hip replacement (THR) than in ORIF; pain—greater in ORIF than in THA; reoperation
rate—ORIF (20%-30%; with AVN [30%]; with nonunion [16%]) vs THA (5%-7%); reasons for ORIF failure—
AVN and nonunion; mechanical failure of fixation or biologic failure of healing (often unable to differentiate); elderly
patients—fixation relies on stability of lateral cortex (able to resist varus force); young patients—92 patients at 2 yr;
similar rates of AVN (16%) and nonunion (17.4%); AVN seemingly unaffected by delay in surgery >48 hr
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| Blood supply to femoral head: early study led to belief that blood supply depends on terminal branch of medial
femoral circumflex artery (MFCA); later studies showed femoral nailing injured terminal branch without causing
AVN in adult femur; other studies found blood also supplied by posterosuperior branch, posteroinferior branch,
and foveal vessel; speaker’s findings—based on investigations; vasculature of femoral neck not quite as tenuous as
believed; rich anastomosis extraosseously around femoral neck; posterosuperior and posteroinferior branches of
MFCA supply blood to head; foveal vessel present; surgical goal—minimize complications of dysvascularity; heal
femoral neck; maintain hip anatomy (avoiding second procedure, eg, femoral neck impingement and shortening of
abductors necessitating relative lengthening)
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| Implant and treatment: impact on healing (based on literature)—distance between anterior and posterior screws
on lateral x-ray critical; unrelated to parallel screw placement (ie, minimized sliding); current issues—obtaining
reduction key; locked plate not answer; mechanical problem remains unsolved; ability to improve bone density
limited (solution to problem expected); risk for redisplacement—increased by inferior offset of fracture and
varus malalignment; unaffected by fracture type (Garden 3 or 4), bone density, vertical fracture angle, inferior
comminution, or valgus angulation; reduction critical factor — fixation holds reduction
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 | Indications for THA: patient >70 yr of age (although ORIF possible in physiologically young patient); possibly
smoking
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| ORIF: mini-open procedure; strategic application of compression screw (in area of tension from deformity of fracture);
bone morphogenetic protein (BMP) to augment biology; locking into place with device, preferably locked
compression plate (LCP); speaker’s results—after ≈100 cases; only one subsequent AVN
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| Summary comments: not advocating ORIF for all femoral neck fractures (tailor approach to individual geriatric
patient); if unable to restore anatomy, THA indicated; degree of displacement not criterion; reduction on operating
table critical (cannot rely on device alone to hold in place during healing); restoring stability of calcar essential (apply
compression); nonsliding device to maintain length; fixed-angle device to maintain alignment; role of osteoconductive
agents uncertain (BMP used to induce new bone formation, and, more importantly, to induce revascularization
of head); coating implant with hydroxyapatite (HA) can improve fixation
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| ORTHOBIOLOGICS AND ORTHOPAEDICS —Thomas A. Einhorn, MD, Professor and Chair, Department of Orthopaedic
Surgery, Boston University School of Medicine, Boston, MA
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| Evidence and practice: while level I evidence may be lacking for particular therapy, important for orthopaedists
to understand evidence available; may help in discussions with patients about therapies not yet supported by high-
quality evidence
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| Context: almost 8 million fractures annually in United States; many experience delay or impairment in healing; orthobiologic
materials developed to correct problems in healing
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| Tissue repair factors: future prospects unclear; thrombin peptides (crystallin found unsuccessful in meeting outcome
measure); other technologies under development—fibroblast growth factor; vascular endothelial growth factor; growth
hormone; platelet-derived growth factor; prostaglandin agonists
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| Autologous blood concentrate: autologous growth factors (AGF); level I and level II evidence lacking; level III
study found AGF inferior to autologous bone graft in spinal arthrodesis
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| Autologous bone marrow: osteoprogenitor cells harvested from iliac crest; bone marrow aspirate concentrate
contains 4- to 5-fold increase in osteoprogenitor cells (can be combined with allogeneic bone or calcium phosphate
granules to provide off-the-shelf material; can be injected); osteoprogenitor cells delivered in combination with
other cells that support growth and differentiation; level II evidence—percutaneous injection in nonunion site led to
union in 53 of 60 patients
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| BMP: osteoconductive substance derived from demineralized matrix of bone; level II study found demineralized
bone matrix alone may be able to extend smaller quantity of autologous bone graft in achieving spinal fusion; osteogenic
protein (OP)-1—level I study found recombinant osteogenic protein (OP-7) equivalent to autologous bone
in treating tibial nonunions; BMP-2 (Infuse)—level I study of treatment of fresh open tibia fractures found 44% reduction
in number of secondary interventions, fewer hardware failures, fewer infections, and faster wound healing;
subgroup analysis—demonstrated patients with more severe injuries most likely to benefit from BMP
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| DEMINERALIZED BONE MATRIX: A USEFUL ADJUNCT? —Bradley R. Merk, MD, Assistant Professor of Orthopaedic
Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL
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| Underlying concerns: wide use of BMP does not necessarily mean it works; largely market-driven; Food and
Drug Administration does not require efficacy before marketing; efficacy—needs to be compared to iliac crest bone
graft (ICBG; gold standard); since 1966, no study comparing BMP to ICBG
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| Further considerations: advantages—osteoinductivity demonstrated in animal models (but not in humans); limitless
supply; easy to use; disadvantages—cost; effectiveness not well established; no structural support; limited osteoconductivity;
causes endochondral and intramembranous ossification in animal models; how produced—acid
extraction resulting in protein; factors affecting efficacy—donor source; handling and sterilization; fiber content;
carrier (differs among products); variability—2006 study found wide interproduct and intraproduct variability in
amount of BMP-2 and BMP-7; unknown whether contents of individual product sufficient for clinical efficacy
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| Conclusion on BMP: anecdotal evidence of efficacy when used alone; useful as graft extender; unknown factors—
how to process; quality of product used; optimal indications (alone or as extender)
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Suggested Reading
Bhandari M et al: Operative treatment of extra-articular proximal tibial fractures. J Orthop Trauma 17:591, 2003;
Bogehoj M et al: Blood flow and microdialysis in the human femoral head. Acta Orthop 78:56, 2007; Bono CM et
al: Neurovascular and tendinous damage with placement of anteroposterior distal locking bolts in the tibia. J Orthop
Trauma 17:677, 2003; Colnot C et al: Mechanisms of action of demineralized bone matrix in the repair of cortical
bone defects. Clin Orthop Relat Res:69, 2005; Darder-Garcia A et al: Nonreamed flexible locked intramedullary
nailing in tibial open fractures. Clin Orthop Relat Res:97, 1998; Garcia-Lopez A et al: Unreamed intramedullary
locking nailing for open tibial fractures. Int Orthop22:97, 1998; Gardner MJ et al: Surgical treatment and outcomes
of extraarticular proximal tibial nonunions. Arch Orthop Trauma Surg Gardner MJ et al: Vascular implications of
minimally invasive plating of proximal humerus fractures. J Orthop Trauma 20:602, 2006; Hernigou P et al: Percutaneous
autologous bone-marrow grafting for nonunions. Surgical technique. J Bone Joint Surg Am 88 Suppl 1 Pt
2:322, 2006; Hussain R et al: Treatment of tibial diaphyseal fractures with closed flexible intramedullary ender
nails: 39 fractures followed for a period of two to seven years. J Pak Med Assoc 51:190, 2001; Jeon EJ et al: Bone
morphogenetic protein-2 stimulates Runx2 acetylation. J Biol Chem 281:16502, 2006; Konrath G et al: Intramedullary
nailing of unstable diaphyseal fractures of the tibia with distal intraarticular involvement. J Orthop Trauma 11:200,
1997; Patel VV et al: Controlling bone morphogenetic protein diffusion and bone morphogenetic protein-stimulated
bone growth using fibrin glue. Spine 31:1201, 2006; Sussmann PS et al: Vascular preservation during arthroscopic
osteoplasty of the femoral head-neck junction: a cadaveric investigation. Arthroscopy 23:738, 2007; Swiontkowski
MF et al: Recombinant human bone morphogenetic protein-2 in open tibial fractures. A subgroup analysis of data
combined from two prospective randomized studies. J Bone Joint Surg Am 88:1258, 2006; Wu CC et al: High success
rate with exchange nailing to treat a tibial shaft aseptic nonunion. J Orthop Trauma 13:33, 1999; Wu CC: Salvage
of proximal tibial malunion or nonunion with the use of angled blade plate. Arch Orthop Trauma Surg 126:82,
2006.
Educational Objectives
| The goal of this program is to enable orthopaedists to improve treatment of traumatic injuries. After hearing and assimilating
this program, the orthopaedic surgeon will be better able to:
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| 1. Diagnose tibial malunions.
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| 2. Employ nailing, plating, or external fixation in stabilizing tibial malunions.
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| 3. Describe the blood supply to the femoral head.
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| 4. Choose between open reduction and internal fixation (ORIF) and total hip arthroplasty (THA) in treating femoral
neck injuries.
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| 5. Include orthobiologic materials in the treatment of fractures.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members 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 following has been disclosed: Dr. Reilly—Synthes
(research support); Dr. Einhorn—Stryker, Bioset, GlaxoSmithKline, Zelos (honoraria and research grants)
Acknowledgements
Drs. Reilly, Lorich, Einhorn, and Merk were recorded at the 9th Annual Chicago Trauma Symposium (Matthew J. Jimenez,
Course Chair), held in Chicago, IL, August 10-12, 2007. The Audio-Digest Foundation thanks the speakers and
the sponsor, with special thanks to Dr. Jimenez, for their cooperation in the production of this program.
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