Fracture stabilization, bone grafting when necessary, wound closure or coverage, and the initiation of rehabilitation within 3 days of injury may provide the best opportunity for optimal functional recovery of open hand fractures.44,45 Successful delayed primary bone grafting of open diaphyseal defects has been reported.35,37,45,49 Primary bone grafting may safely expedite the recovery of open hand fractures with bone loss.15,45,49 A contemporary retrospective study of three patients suggests that immediate bone grafting in clean stable wounds may be equally as effective and safe as delayed primary bone grafting.90
Functional recovery and minimizing morbidity are the fundamental goals of rehabilitation.35,55 Early digital motion and tendon gliding exercises are prioritized. Elevation augments digital motion by diminishing and resolving swelling and edema and consequently decreasing resistance to tendon gliding and joint motion.55,56 Progress is guided by soft tissue response, fracture stability, and the patient's pain tolerance; stopping short of generating additional inflammatory or fibroblastic response. Fracture stability limits pain and allows more rapid and intense implementation of exercises. A recent review of 459 patients with simple closed metacarpal shaft fractures indicated that early motion (initiated within 21 days after injury) resulted in earlier recovery of motion and strength, facilitated an earlier return to work, and did not affect fracture alignment.28 A current prospective controlled laboratory investigation in dogs indicated that synergistic wrist and digital exercises diminished adhesion formation after tendon lacerations and augmented the recovery of motion.101
Fractures treated with wire fixation may require more caution in implementing exercises during the first 4 weeks after injury than additional fractures secured with mini screws or plates.68 Rehabilitation must be modulated to initiate motion but to avoid loosening the wires and losing the fracture reduction. Previous data have indicted that the recovery of 4 to 5 mm of flexor tendon excursion during the first 4 weeks after flexor tendon repair within the flexor tendon sheath substantially decreased the formation of permanent adhesions between bone and tendon.22 Extrapolation of these findings to proximal phalangeal fractures and allowance for 4 to 5 mm of adjacent flexor and extensor tendon excursion would require a 40° to 50° partial arc of proximal interphalangeal joint motion.10,50,98,99 A recent prospective controlled laboratory study of 96 repaired flexor digitorum profundus tendons in 48 dogs suggests that as little as 1.7 mm of flexor tendon excursion during the first 4 weeks after injury may reliably diminish adhesions.88 Consequently, we believe that therapy for patients whose phalangeal fractures are treated with Kirschner wires should particularly focus on regaining at least 50° of proximal interphalangeal joint motion with as much extension as possible within these confines during the first 4 weeks after surgery.10,50,98,99 We hypothesize that this limitation in motion may be relatively safe in preventing wire and fracture displacement while minimizing the risk of adhesions and stiffness, but data are needed for confirmation.
Hand fracture treatment should be driven by evidence-based, statistically confirmed principles and patient satisfaction and safety rather than by market forces.5,7,11,82 Although information of value may be discerned from any report, declarations of study design and evidence level help the reader gain prospective. Blinded unbiased prospective randomized controlled studies with adequate enrollments and well-defined criteria provide the highest level of validity.32,53,61,62 Information from past reports may be reviewed to establish levels of evidence, validity, confidence levels, and absolute and relative risks.86
When prospective controlled studies are not feasible, posing an appropriate research question and improving study design may enhance research quality.51 Collaborative efforts and multicenter studies do not necessarily improve study validity.61,62 Heterogeneity of study discriminators has hindered valid meta-analysis to date.6,61,62 Scientists are striving to find universally acceptable classifications for fractures, wounding, and outcomes to assist in addressing this deficiency. More patient outcome and quality of care reports are needed to assess subjective patient improvement, satisfaction, and safety.8,59,89
Investigator bias may exist and conflicts of interest must be taken into consideration.61,62,102 Look for blinded studies and unconflicted collaborative confirmation of outcomes from sources independent of manufacturers, innovators, and advocates. Marketing advertisements may contain suspect information.7,82 Product expectations have not always been fulfilled, even when based upon sound theory.
We have cited selected new reports from 1999 forward that we thought might positively impact hand fracture treatment in the future. We identified the study design to allow the reader to correlate the data with currently accepted levels of evidence.5,11,86 Concepts often need additional supporting evidence to confirm their validity.32,61,62 This review was admittedly not exhaustive and represents our bias.
Past studies suggest that hand fracture outcomes correlate most highly with initial injury severity, but may include a multiplicity of factors.30,94 Patient factors (age, chronic illness, socioeconomic factors, and patient understanding and motivation); fracture factors (location, type, displacement, stability, soft tissue injury, and soiling); and treatment factors (recognition of injury, timing of intervention, tissue treatment, fracture reduction, surgical procedures, maintenance of reduction, mobilization of joints and tendons, and treatment of complications) may individually and collectively impact outcome. The physician can control only treatment factors.
Though acceptable anatomic reduction parameters and fracture principles guide physicians, they are currently relative rather than absolute, allowing the treatment of each patient to remain an individual consideration.1,9,18,35,70,93,97 Two recent prospective controlled studies confirm that slight metacarpal shortening and angulation may be well tolerated in otherwise asymptomatic patients, often sparing them from the additional dangers and morbidity of surgery.2,73 We must continue to educate the members of the medical and legal professions, health care insurers, and the general public that the risk to benefit ratio may be reasonably best served to render optimal functional outcome in some instances by accepting some anatomic imperfection as an alternative to the surgical risks and postoperative patient morbidity that may be associated with an attempt to attain perfect anatomic restoration.
Hand fractures may be complicated by deformity from no treatment, stiffness from over-treatment, and deformity and stiffness from poor treatment.95 Stiffness is the most common complication of hand fractures and is primarily related to initial injury severity and the site of injury.16,21,63,80,94 Simple open fractures accompanied by skin laceration have only slightly greater risk of stiffness than their closed counterparts of comparable configuration, but complex injury and delay in treatment substantially increase risk. Comminuted fractures are inherently unstable; are more frequently compounded by crush, wounding, and tendon, nerve, and vascular injury; and have a higher risk of stiffness than simple fractures. The proximal interphalangeal joints of the fingers are especially susceptible to stiffness.67 Open reduction and internal fracture fixation, even when essential, may add to the risk of delayed union or digital stiffness.21,43,77 Two contemporary reports indicated that open plate fixation of diaphyseal fractures lead to fragment devascularization and delayed healing.17,42 Transverse fractures may be at greater risk for these hazards than other configurations owing to the small surface area of the fracture.42 Plate bulk may contribute to stiffness, especially when the plate is applied proximate to a joint.76,79
When stabilization is necessary, a recent retrospective case report suggests that oblique as well as transverse metacarpal fractures may be successfully treated with multiple percutaneous fasciculated intramedullary Kirschner wires.27 More data may be needed to establish true statistical validity owing to small enrollment.61,62 Similarly, a novel percutaneous intramedullary flexible locking nail has been described that may have excellent potential for minimally traumatic stabilization of closed extra-articular metacarpal and phalangeal fractures of all configurations, however data are not yet available.75 A recent prospective controlled biomechanical study demonstrated that unicortical fixation of mini plates is of comparable stability to bicortical fixation for transverse diaphyseal metacarpal fractures while creating less damage to the bone.84
Ideally, fracture stabilization should be pursued with the least possible amount of additional soft tissue trauma necessary. A recent prospective randomized controlled study with blinded analysis implied that open mini screw fixation of simple closed oblique extra-articular proximal phalangeal fractures may be an exception to this tenet and may produce results comparable to those of percutaneous wire fixation.4,52,57,65,100 More data may be needed to establish true statistical validity.61,62 This same study describes the use of a previously reported unilateral excision of the lateral band and oblique fibers of the extensor apparatus of the metacarpophalangeal joint to approach and secure the proximal phalanx from the lateral aspect. The investigators provide an account of the procedure's efficacy, but not specific documentation.40,57 Further study is needed.
Another retrospective case study indicates that bicortical screw fixation of 37 extraarticular oblique phalangeal fractures were consistently effective in achieving union without loss of fixation or deformity. This technical modification simplifies mini screw insertion and is equally as effective as lag screw fixation.84
Open fractures should ideally be debrided within the first 24 hours after injury to prevent bacterial colonization and the establishment of pervasive deep infection.45,96 The safe timing of fracture fixation, bone grafting, and wound closure or coverage is more dependent on the wound being stable and surgically clean (fewer than 105 bacteria/cc) than upon the time since injury.64 The best results in open hand fractures may be achieved when the repair or reconstruction of complex wounds is completed within 3 days after injury.44 Primary bone grafting would implement this goal.15,45,49 A contemporary small case series indicates that bone grafting (within 24 hours after injury) may be safe in a stable clean wound.90 Additional data are needed. Mini plate fixation is especially suitable for open extra-articular hand fractures with comminution or bone loss. Stable fixation is a deterrent to infection.41
A recent prospective controlled study on dogs indicates that as little as 1.7 mm of flexor tendon excursion during the first 4 weeks after injury or surgery diminishes peritendonous adhesions.88 Another contemporary prospective controlled investigation on dogs indicates that synchronous wrist and digital motion improves tendon excursion.101 Correlation in human subjects with proximal phalangeal fractures is needed. A recent Level III review indicates that early motion lessens morbidity after closed simple metacarpal fractures without disturbing fracture alignment.28
Fixed angle-locking screws are on the horizon and will add strength to the bone-mini plate construct without requiring additional soft tissue dissection. Locking screws do not back out of the plate, afford additional stability, and may be particularly advantageous in osteopenic bone. Tissue glue may play some role in the future of hand fracture treatment. Reports of osteoconductive and osteoinductive bone graft substitutes in the treatment of hand fractures may be on the horizon. Resorbable implants have not achieved wide acceptance to date, but may play a more important role in the future. Percutaneous screw fixation has been reported, but few data are available.33,39
There is much work to be done in the future, analyzing and verifying both old and new concepts and in refining and developing hand fracture treatment strategies.
The authors thank Igor Indriago, MD, and Amel Touhami, MD, CTBS, for their contributions to this study.
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