Outcome of surgical repair of adult digital nerve injury: a systematic review

Minimally Invasive Suture Technique Pull-out to Repair the Acute Flexor Tendons in Zone II of the Hand

Objective:  To evaluate the safety and effectiveness of a modified pull-out suture technique in patients undergoing primary repair surgery for injuries to the flexor tendons of the fingers with Total Active Motion (TAM) as the primary outcome. Method:  A total of 29 patients (38 fingers) were chosen from both sexes, aged between 18 and 65 years with clean acute tendon laceration occurring within 15 days, in the Verdan's zone II of flexor tendon in the hand, when only the deep flexor tendon was sutured, either associated or not with digital nerve injury. The patients were operated on using the proposed technique and evaluated at 3, 9 and 24-weeks PO. The primary outcome was the assessment of Total Active Movement (TAM) and 3 classifications were employed: Strickland, IFSSH and Buck-Gramcko. Results:  We observed a total active motion (TAM) of 209.3 °at the end of 24 weeks; 83.0% of Good and Excellent results by the Modified Strickland Classification, 93% of Excellent results by the IFSSH Classification, and 97% of Good and Excellent results using the Buck-Gramcko Classification. There were no cases of rupture, but tendon adhesion was observed in 3 fingers. Conclusion:  The present suture technique proved to be safe and effective with a low rate of complications, obtaining an excellent functional result in terms of total active mobility, according to the evaluations and classifications used.

Non degradation of chitosan and initial degradation of collagen nerve conduits used for protection of nerve coaptations

BACKGROUND

Nerve conduits are either used to bridge nerve gaps of up to 3 cm or to protect nerve coaptations. Biodegradable nerve conduits, which are currently commercially available, include Chitosan or collagen-based ones. As histological aspects of their degradation are highly relevant for the progress of neuronal regeneration, the aim of this study was to report the histopathological signs of such nerve conduits, which were removed during revision surgery.

MATERIALS AND METHODS

Either Chitosan (n = 2) or collagen (n = 2) nerve conduits were implanted after neuroma resection and nerve grafting (n = 2) or traumatic nerve lesion after cut (n = 1) or crush injury (n = 1) in two females and two men, aged between 17 and 57 years. Revision surgery with removal of the nerve conduits was indicated due to persisting neuropathic pain and sensorimotor deficits, limited joint motion, or neurolysis with hardware removal at a median time of 17 months (range: 5.5-48 months). Histopathological analyses of all removed nerve conduits were performed.

RESULTS

A scar neuroma was diagnosed in one out of four patients. Mechanical complication occurred in one patient after nerve conduit implantation bridged over finger joints. Intraoperatively no or only initial signs of degradation of the nerve conduits were observed. Chitosan conduits revealed largely unchanged shape and structure of chitosan, and coating of the conduit by a vascularized fibrous membrane. The latter contained deposits taken up by macrophages, most likely representing dissolved chitosan. Characteristic histopathologic features of the degradation of collagen conduits were a disintegration of the compact collagen into separate fine circular strands, No foreign body reaction was observed in all removed nerve conduits.

CONCLUSIONS

Both Chitosan nerve conduits have not been degraded. The collagen nerve conduits showed a beginning degradation process. Furthermore, wrapping the repaired nerve with a nerve conduit did neither prevent adhesions nor improved nerve gliding. Therefore, biodegradation in time should be particularly addressed in further developments of nerve conduits.

Digital nerve injury: to repair or not?

BACKGROUND

There are very few studies comparing patients with and without repair after digital nerve injury. It is still controversial whether digital nerve repair is necessary.

AIMS

The aim of this study was to evaluate the long-term clinical outcomes of patients with unilateral isolated digital nerve injury who underwent surgical repair and those who did not.

METHODS

Seventy-four patients with unilateral digital nerve injury were included in the study. Of these, the patients who underwent surgical repair were determined as group A (n = 42), the patients without repair as group B (n = 32), and the groups were divided into subgroups according to injury levels. Results were evaluated with a minimum follow-up of 24 months.

RESULTS

When the S2PD results were evaluated overall, it was found that those who had digital nerve repair (group A) had significantly better outcomes compared to those without repair (group B) (p = 0.012). When the subgroups were evaluated according to the injury localization, no significant difference was observed at the distal levels, while it was observed that the patients who underwent repair in the proximal levels showed significantly better results (p = 0.003, p = 0.012).

CONCLUSION

In this study, it was seen that there was no difference between the results of repair and non-repair of unilateral nerve injuries distal to the middle level of the middle phalanx, but repair is required in injuries proximal to this level.

Precise Monitoring of Returning Sensation in Digital-Nerve Lesions by Three-Dimensional Imaging: A Proof-of-Concept Study

SUMMARY

Digital-nerve lesions result in a loss of tactile sensation reflected by an anesthetic area (AA) at the radial or ulnar aspect of the respective digit. Available tools to monitor the recovery of tactile sense have been criticized for their lack of validity. Precise quantification of AA dynamics by three-dimensional (3D) imaging could serve as an accurate surrogate to monitor recovery after digital-nerve repair. For validation, AAs were marked on digits of healthy volunteers to simulate the AA of an impaired cutaneous innervation. The 3D models were composed from raw images that had been acquired with a 3D camera to precisely quantify relative AA for each digit (3D models, n = 80). Operator properties varied with regard to individual experience in 3D imaging and image processing. In addition, the concept was applied in a clinical case study. Results showed that images taken by experienced photographers were rated as better quality ( P < 0.001) and needed less processing time ( P = 0.020). Quantification of the relative AA was not altered significantly, regardless of experience level of the photographer ( P = 0.425) or image assembler ( P = 0.749). The proposed concept allows precise and reliable surface quantification of digits and can be performed consistently without relevant distortion by lack of examiner experience. Routine 3D imaging of the AA has the great potential to provide visual evidence of various returning states of sensation and to convert sensory nerve recovery into a metric variable with high responsiveness to temporal progress.

Treatment options for digital nerve injury: a systematic review and meta-analysis

BACKGROUND

Surgical treatment of finger nerve injury is common for hand trauma. However, there are various surgical options with different functional outcomes. The aims of this study are to compare the outcomes of various finger nerve surgeries and to identify factors associated with the postsurgical outcomes via a systematic review and meta-analysis.

METHODS

The literature related to digital nerve repairs were retrieved comprehensively by searching the online databases of PubMed from January 1, 1965, to August 31, 2021. Data extraction, assessment of bias risk and the quality evaluation were then performed. Meta-analysis was performed using the postoperative static 2-point discrimination (S2PD) value, moving 2-point discrimination (M2PD) value, and Semmes-Weinstein monofilament testing (SWMF) good rate, modified Highet classification of nerve recovery good rate. Statistical analysis was performed using the R (V.3.6.3) software. The random effects model was used for the analysis. A systematic review was also performed on the other influencing factors especially the type of injury and postoperative complications of digital nerve repair.

RESULTS

Sixty-six studies with 2446 cases were included in this study. The polyglycolic acid conduit group has the best S2PD value (6.71 mm), while the neurorrhaphy group has the best M2PD value (4.91 mm). End-to-side coaptation has the highest modified Highet's scoring (98%), and autologous nerve graft has the highest SWMF (91%). Age, the size of the gap, and the type of injury were factors that may affect recovery. The type of injury has an impact on the postoperative outcome of neurorrhaphy. Complications reported in the studies were mainly neuroma, cold sensitivity, paresthesia, postoperative infection, and pain.

CONCLUSION

Our study demonstrated that the results of surgical treatment of digital nerve injury are generally satisfactory; however, no nerve repair method has absolute advantages. When choosing a surgical approach to repair finger nerve injury, we must comprehensively consider various factors, especially the gap size of the nerve defect, and postoperative complications. Type of study/level of evidence Therapeutic IV.

Promotion effect of TGF-β-Zfp423-ApoD pathway on lip sensory recovery after nerve sacrifice caused by nerve collateral compensation

Resection of oral and maxillofacial tumors is often accompanied by the inferior alveolar nerve neurectomy, resulting in abnormal sensation in lower lip. It is generally believed that spontaneous sensory recovery in this nerve injury is difficult. However, during our follow-up, patients with inferior alveolar nerve sacrifice showed different degrees of lower lip sensory recovery. In this study, a prospective cohort study was conducted to demonstrate this phenomenon and analyze the factors influencing sensory recovery. A mental nerve transection model of Thy1-YFP mice and tissue clearing technique were used to explore possible mechanisms in this process. Gene silencing and overexpression experiments were then conducted to detect the changes in cell morphology and molecular markers. In our follow-up, 75% of patients with unilateral inferior alveolar nerve neurectomy had complete sensory recovery of the lower lip 12 months postoperatively. Patients with younger age, malignant tumors, and preservation of ipsilateral buccal and lingual nerves had a shorter recovery time. The buccal nerve collateral sprouting compensation was observed in the lower lip tissue of Thy1-YFP mice. ApoD was demonstrated to be involved in axon growth and peripheral nerve sensory recovery in the animal model. TGF-β inhibited the expression of STAT3 and the transcription of ApoD in Schwann cells through Zfp423. Overall, after sacrificing the inferior alveolar nerve, the collateral compensation of the ipsilateral buccal nerve could innervate the sensation. And this process was regulated by TGF-β-Zfp423-ApoD pathway.

Is microsurgical experience essential in Zone II flexor tendon injuries?

OBJECTIVES

This study aims to investigate whether microsurgical experience was necessary for the treatment of Zone II flexor tendon injuries.

PATIENTS AND METHODS

Between October 2018 and October 2021, a total of 73 Zone II flexor tendon injuries in 71 patients (53 males, 18 females; mean age: 39.6±12.1 years; range, 21 to 57 years) who underwent surgical intervention in our center were retrospectively analyzed. All patients in the study had flexor digitorum profundus (FDP) tendon injury. The clinical outcomes of patients with digital artery injury, nerve injury or phalanx fracture accompanying FDP tendon injury were evaluated separately according to the American Society for Surgery of the Hand (ASSH) scores. The scores of multiple injuries accompanying FDP tendon injury in patients with FDP+flexor digitorum superficialis (FDS)+digital nerve injury and FDP+FDS+digital artery+nerve injury were evaluated.

RESULTS

The mean ASSH score was 69.4±28.2 in the group with FDP tendon injury accompanying digital nerve injury and 62.9±19.7 in the group with FDP tendon injury and digital artery injury. The clinical outcomes were significantly lower in patients with digital nerve injury and digital artery injury respectively, compared to patients without accompanying injuries (p=0.029 and p=0.012, respectively). The lowest mean score (45.3±10.2) was in patients with fracture accompanying FDP tendon injury and ASSH score was significantly lower than in patients without fracture (p<0.001).

CONCLUSION

Zone II flexor tendon injuries are frequently accompanied by digital artery or nerve injuries, which usually require microsurgical repair. If left untreated, treatment outcome may be poor. Surgical centers and departments undertaking the treatment of flexor tendon injuries should be able to perform microsurgery.

Outcomes of Flexor Tendon Repair in Patients With Concurrent Neurovascular Injuries of Multiple Digits in Zone 1

PURPOSE

We treated several patients with multiple flexor (flexor digitorum profundus; FDP) injuries accompanied by injuries to the digital nerve or vessels around the distal interphalangeal crease (zone 1). Here, we retrospectively report the outcomes and review the literature.

MATERIALS AND METHODS

Between January 2010 and December 2018, 16 patients who met the study inclusion criteria were investigated. Tendons were repaired using the cross-locked cruciate (Adelaide) technique (6-strand) or modified Becker method (4-strand). The neurovascular structures were repaired under a microscope.

RESULTS

Sixteen patients (47 digits) were treated. According to the criteria of Moiemen and Elliot, the lacerated areas were in zones IA and IB in 7 and 40 digits, respectively. The mean ranges of motion were 149.27 ± 7.78 and 66.43 ± 2.04 degrees according to the Strickland and modified Strickland assessments, respectively. The mean 2-point discrimination was 5.00 ± 0.63 mm. Four patients (group 1) presented with injuries to 2 digits, and 9 (group 2) and 3 (group 3) patients had 3 and 4 injured digits, respectively. The outcomes were satisfactory in terms of the mean range of motion; 2-point discrimination; cold tolerance; visual analog scale pain score; Disabilities of the Arm, Shoulder, and Hand score; and grip strength. There were no differences among the groups.

CONCLUSIONS

Open multiple-finger injuries involving flexor digitorum profundus rupture with concurrent neurovascular injuries on one or both sides occasionally occur in industrial environments. Fortunately, each digit exhibits a consistent injury type in a particular anatomical location; appropriate repair yields satisfactory outcomes despite the presence of multiple injuries.

Electric shock sign after digital nerve injury; report of a case and review of literature

INTRODUCTION AND IMPORTANCE

Digital nerve lacerations are rationally common, especially following penetrating injuries. The majority of patients suffer from numbness as the main complaint. However, electric shock pain is a rare manifestation of partial nerve injury.

CASE PRESENTATION

A 65-year-old woman with partial digital nerve injury and an electric shock sign due to a 1 cm laceration on the volar side of the proximal phalanx three weeks earlier. The surgical exploration revealed a neuroma-like mass in the digital nerve; however, the continuity of the nerve was grossly intact.

CLINICAL DISCUSSION

Due to the superficiality of digital nerves, penetrating nerve injuries are rationally common in this area. Laceration of the digital nerve could lead to loss of sensation, clumsiness, and even loss of function. Gradually, neuroma formation would add a local pain and electric shock sign to the mentioned symptoms.

CONCLUSION

Electric shock sign is characteristic for partial digital nerve injury with unknown mechanism. It seems the symptoms would be progressive and more complicated with neuroma formation.

LEVEL OF EVIDENCE

V.

Cold sensitivity, functional disability and predicting factors after a repaired digital nerve injury

To investigate self-reported cold sensitivity and functional disability after a repaired digital nerve injury. We identified 3204 individuals operated with digital nerve repair in the Swedish national quality registry for hand surgery (HAKIR). Patient-reported symptoms, including cold sensitivity and perceived disability, were examined using two questionnaires (HQ-8 and QuickDASH), three and 12 months postoperatively. Patients with diabetes (n = 48; 3%) were identified in the Swedish National Diabetes Register (NDR). Cold sensitivity (scored 0–100) was the most prominent symptom among 1553 included individuals (998 men, 555 women; median age 41 [IQR 27–54] years). In the regression analysis, flexor tendon injury, hand fracture and injury to multiple structures predicted worsened cold sensitivity (6.9, 15.5 and 25.0 points; p = 0.005, 0.046 and < 0.001) at 12 months. Individuals with moderate (30–70) and severe (> 70) cold sensitivity had higher QuickDASH scores at three and 12 months postoperatively than individuals with mild cold sensitivity (6.0 and 5.5; 19.8 and 21.0 points; p = 0.001). Flexor tendon injury, injuries to multiple structures and diabetes had significant effect on QuickDASH scores at three, but not at 12, months postoperatively. Cold sensitivity is common after a digital nerve repair and impacts self-reported disability. A concomitant injury, particularly multiple injuries, predicts postoperative cold sensitivity.

Influence of surface peripheral electrical stimulation on nerve regeneration after digital nerve neurorrhaphy: study protocol for a randomized clinical trial

We will study the influence of low intensity and frequency surface peripheral electrical stimulation (PES) on nerve regeneration of digital nerve injuries of the hand after its surgical repair in humans. Participants will be patients with acute traumatic peripheral nerve injury referred to the Hand Surgery Service of the General Hospital of the State of Bahia, a reference service in the state. These patients will undergo surgery followed by PES in the immediate postoperative period. After hospital discharge, they will be followed up on an outpatient basis by researchers, who will remotely supervise a physiotherapy program. Our hypothesis is that PES will positively influence the recovery of sensory function in patients undergoing neurorrhaphy of digital nerves of the hand.

ReBEC registration:  U1111-1259-1998 (12/18/2020)

Traumatized Hand - Update at the First Visit

The hand is the segment most exposed to trauma, with a large volume of care in urgent and emergency services. Therefore, it is necessary that physicians on duty have the essential knowledge to effectively manage these injuries. In the present article, we will review the main conditions and conduct guidelines.

Comparison of nerve conduits and nerve graft in digital nerve regeneration: A systematic review and meta-analysis

The goal of this systematic review and meta-analysis was to compare nerve conduits and nerve graft for peripheral nerve regeneration. This type of lesion frequently causes disability due to pain, paresthesia and motor deficit. On the PICO process, "P" corresponded to patients with peripheral digital nerve lesions of any age, gender or ethnicity, "I" to interventions with nerve conduits or nerve graft, "C" to the control group with no treatment, placebo or receiving other treatment, and "O" to outcome assessment of nerve regeneration. Initial search found in 3859 studies, including 2001 duplicates. The remaining 1858 studies were selected by title and/or abstract; 1798 articles were excluded, leaving 60 articles for full-text review. Thirty-nine of these 60 reports were excluded as not meeting our inclusion criteria, and 21 articles were ultimately included in the systematic review. For patients older than 40 years, there was a greater mean improvement on S2PD and M2PD tests with grafting, which seemed to be the better surgical technique, positively impacting prognosis. On the M2PD test, there was significantly greater improvement in 11-17.99 mm defects with grafting (P < 0.001); this finding should guide surgical strategy in peripheral nerve regeneration, to ensure better outcomes.

Injury-Induced HSP27 Expression in Peripheral Nervous Tissue Is Not Associated with Any Alteration in Axonal Outgrowth after Immediate or Delayed Nerve Repair

We investigated injury-induced heat shock protein 27 (HSP27) expression and its association to axonal outgrowth after injury and different nerve repair models in healthy Wistar and diabetic Goto-Kakizaki rats. By immunohistochemistry, expression of HSP27 in sciatic nerves and DRG and axonal outgrowth (neurofilaments) in sciatic nerves were analyzed after no, immediate, and delayed (7-day delay) nerve repairs (7- or 14-day follow-up). An increased HSP27 expression in nerves and in DRG at the uninjured side was associated with diabetes. HSP27 expression in nerves and in DRG increased substantially after the nerve injuries, being higher at the site where axons and Schwann cells interacted. Regression analysis indicated a positive influence of immediate nerve repair compared to an unrepaired injury, but a shortly delayed nerve repair had no impact on axonal outgrowth. Diabetes was associated with a decreased axonal outgrowth. The increased expression of HSP27 in sciatic nerve and DRG did not influence axonal outgrowth. Injured sciatic nerves should appropriately be repaired in healthy and diabetic rats, but a short delay does not influence axonal outgrowth. HSP27 expression in sciatic nerve or DRG, despite an increase after nerve injury with or without a repair, is not associated with any alteration in axonal outgrowth.

Safety and efficacy of a nerve matrix membrane as a collagen nerve wrapping: a randomized, single-blind, multicenter clinical trial

A new nerve matrix membrane derived from decellularized porcine nerves has been shown to retain the major extracellular matrix components, and to be effective in preventing adhesion between the nerve anastomosis sites and the surrounding tissues in a rat sciatic nerve transection model, thereby enhancing regeneration of the nerve. The effectiveness of the membrane may be attributed to its various bioactive components. In this prospective, randomized, single-blind, parallel-controlled multicenter clinical trial, we compared the safety and efficacy of the new nerve matrix membrane with a previously approved bovine tendon-derived type I collagen nerve wrapping. A total of 120 patients with peripheral nerve injury were recruited from Beijing Jishuitan Hospital, The First Bethune Hospital of Jilin University, and Yantai Yuhuangding Hospital, China. The patients were randomly assigned to undergo end-to-end and tension-free neurorrhaphy with nerve matrix membrane (n = 60, 52 male, 8 female, mean age 41.34 years, experimental group) or tendon-derived collagen nerve wrapping (n = 60, 42 male, 18 female, mean age 40.17 years, control group). Patients were followed-up at 14 ± 5, 30 ± 7, 90 ± 10 and 180 ± 20 days after the operation. Safety evaluation included analyses of local and systemic reactions, related laboratory tests, and adverse reactions. Efficacy evaluation included a static 2-point discrimination test, a moving 2-point discrimination test, and a Semmes–Weinstein monofilament examination. Sensory nerve function was evaluated with the British Medical Research Council Scale and Semmes–Weinstein monofilament examination. The ratio (percentage) of patients with excellent to good results in sensory nerve recovery 180 ± 20 days after the treatment was used as the primary effectiveness index. The percentages of patients with excellent to good results in the experimental and control groups were 98.00% and 94.44%, respectively, with no significant difference between the two groups. There were no significant differences in the results of routine blood tests, liver and renal function tests, coagulation function tests, or immunoglobulin tests at 14 and 180 days postoperatively between the two groups. These findings suggest that the novel nerve matrix membrane is similar in efficacy to the commercially-available bovine-derived collagen membrane in the repair of peripheral nerve injury, and it may therefore serve as an alternative in the clinical setting. The clinical trial was approved by the Institutional Ethics Committee of Beijing Jishuitan Hospital, China (approval No. 20160902) on October 8, 2016, the Institutional Ethics Committee of the First Bethune Hospital of Jilin University, China (approval No. 160518-088) on December 14, 2016, and the Institutional Ethics Committee of Yantai Yuhuangding Hospital, China (approval No. 2016-10-01) on December 9, 2016. The clinical trial was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR2000033324) on May 28, 2020.

Scalpel edge roughness affects post-transection peripheral nerve regeneration

Background

Gentle and precise tissue dissection reduces collateral tissue damage and preserves its structural quality for optimizing healing. This is particularly true for peripheral nerve neurorrhaphy. Axon regeneration kinetics across the repair is dependent on the amount of intraneural fibrosis. The purpose of this study was to determine whether scalpel blade smoothness was a deterministic factor in the kinetics of postneurorrhaphy peripheral axon regeneration.

Methods

Scalpel transection of the saphenous nerve was performed in 18 female Hartley guinea pigs either by a standard #15 stainless steel scalpel blade or a highly polished version of the same blade. Compound nerve action potential recordings and histochemical assay of neurofilament density proximal and 1 cm distal to the site of nerve transection were quantified postneurorrhaphy at postoperative weeks 5, 9, and 12.

Results

There was no action potential transmission observed in the distal axons immediately after neurorrhaphy. A substantial acceleration of axonal conduction recovery was observed in nerves transected with polished scalpel blades observed by high compound nerve action potential amplitudes at postneurorrhaphy weeks 5 and 9 (P < .05). In addition, an increased recovery of intra-axonal neurofilament density in nerves transected with polished scalpel blades was observed by postoperative week 5 (P < .05).

Conclusion

The quality of the scalpel blade is an important determinate of postsurgical healing. Gentle handling of tissue matters.

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Precise nerve resection reduces lateral axonal injury.

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Collateral nerve damage increases interneural fibrosis that slows regeneration.

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Smoother scalpel blades result in faster structural and functional nerve recovery.

Modification of tubular chitosan-based peripheral nerve implants: applications for simple or more complex approaches

Surgical treatment of peripheral nerve injuries is still a major challenge in human clinic. Up to now, none of the well-developed microsurgical treatment options is able to guarantee a complete restoration of nerve function. This restriction is also effective for novel clinically approved artificial nerve guides. In this review, we compare surgical repair techniques primarily for digital nerve injuries reported with relatively high prevalence to be valuable attempts in clinical digital nerve repair and point out their advantages and shortcomings. We furthermore discuss the use of artificial nerve grafts with a focus on chitosan-based nerve guides, for which our own studies contributed to their approval for clinical use. In the second part of this review, very recent future perspectives for the enhancement of tubular (commonly hollow) nerve guides are discussed in terms of their clinical translatability and ability to form three-dimensional constructs that biomimick the natural nerve structure. This includes materials that have already shown their beneficial potential in in vivo studies like fibrous intraluminal guidance structures, hydrogels, growth factors, and approaches of cell transplantation. Additionally, we highlight upcoming future perspectives comprising co-application of stem cell secretome. From our overview, we conclude that already simple attempts are highly effective to increase the regeneration supporting properties of nerve guides in experimental studies. But for bringing nerve repair with bioartificial nerve grafts to the next level, e.g. repair of defects > 3 cm in human patients, more complex intraluminal guidance structures such as innovatively manufactured hydrogels and likely supplementation of stem cells or their secretome for therapeutic purposes may represent promising future perspectives.

Outcomes of surgical repair of a single digital nerve in adults

Current standard management of a cut digital nerve is end-to-end microsurgical nerve coaptation where possible. A recent systematic review of adult digital nerve injuries that were either repaired or left unrepaired showed that the evidence for good nerve recovery or improved function following nerve repair is poor. In the 30 studies included, only 24% of repaired nerves regained sensory recovery close to or equivalent to estimated pre-injury levels. Neuroma rates were the same in those nerves repaired (4.6%) and those not repaired (5%). Questions under debate include proper assessment methods of outcomes, decision making for repair or no repair to different fingers or the thumb, levels of injury, age, and hand dominance. This review summarizes the major evidence available and debates the surgical dogma that surrounds this injury.