Exploration Of Radial Nerve Research Articles

Prevalence of Radial Nerve Palsy Following Surgical Treatment of Closed Humeral Shaft Fractures: A Comparative Analysis of Outcomes with and without Radial Nerve Exploration

Prevalence of Radial Nerve Palsy Following Surgical Treatment of Closed Humeral Shaft Fractures: A Comparative Analysis of Outcomes with and without Radial Nerve Exploration

In cases of humeral diaphyseal fractures, is lateral approach surgery without radial nerve exploration as effective and safe as conventional surgery?

This study compares the efficacy and safety of lateral approach surgery with and without radial nerve dissection in treating humeral diaphyseal fractures. It assesses clinical, radiological, and complication outcomes, providing a description of the surgical methods and perioperative benefits. We retrospectively analyzed data from 71 patients admitted between May 2015 and December 2022 who underwent lateral approach surgery for humeral diaphyseal fractures. Group 1, consisting of 34 patients without radial nerve dissection, and Group 2, comprising 37 patients with radial nerve dissection, were compared. Parameters such as age, gender, fracture side (right/left), fracture type, follow-up time, surgical duration, blood loss, radiological and clinical evaluations (including Shoulder-Elbow range of motion [ROM] and Quick Disabilities of the Arm, Shoulder, and Hand score [Q-DASH]), and complications were examined. Surgical techniques and outcomes were documented. Both groups exhibited comparable distributions in age, gender, fracture types, and follow-up times (p>0.05). Group 1 demonstrated significantly lower surgical duration and blood loss compared to Group 2 (p<0.05 for both). Clinical assessment revealed satisfactory shoulder and elbow ROM within functional limits for all patients, with no instances of infection. Q-DASH scores were similar between groups. Postoperative radial nerve palsy occurred in one patient in Group 1 and three patients in Group 2, with all cases resolving uneventfully during outpatient follow-ups. Radiological assessment confirmed uneventful union in all patients. Lateral approach surgery without radial nerve dissection for humeral diaphyseal fractures offers comparable effectiveness and safety to conventional surgery, with potential perioperative advantages such as reduced operation time and blood loss.

Radial and ulnar nerve palsies in closed humerus fracture: A case report and literature review

Fractures of the humeral shaft are commonly associated with radial nerve injury because of the anatomical course of the nerve. An ulnar nerve injury is rarely associated with such fractures. We present a case of a humeral shaft fracture with combined radial and ulnar nerve injuries in a female adult patient. The patient subsequently underwent radial and ulnar nerve exploration with internal fixation of the left humerus. According to our literature review, no similar cases were previously reported.

Trifid Radial Nerve Complicating a Routine Posterior Approach to Humeral Shaft

Abstract The posterior approach to the humerus is one of the most common approaches used for osteosynthesis and exploration of the radial nerve. The radial nerve anomalies even though rare are a possibility that the operating surgeon should be aware of during radial nerve exploration. A 42-year-old female presented with closed shaft of humerus fracture. The plan was to expose fracture site using a routine posterior approach and fix it with a dynamic compression plate but to our surprise found a trifurcation of radial nerve in the spiral groove. We describe a rare anomaly of trifurcation of radial nerve in the spiral groove. The nerves were protected, and the fracture was reduced and fixed with a dynamic compression plate.

Exploration of radial nerve in patients with humerus shaft fracture with radial nerve palsy, is it necessary?

&lt;p&gt;Fractures in the distal third of the humerus shaft usually are associated with complete or incomplete radial nerve lesions which may be caused due to traction, entrapment or compression between bony fragments. We managed these patients by bridge plating using minimally invasive percutaneous plate osteosynthesis. A total of 5 patients were operated on and all showed full functional recovery of radial nerve. Fracture united in all cases and no patient developed any complication.&lt;/p&gt;

Postoperative radial nerve palsy in humeral shaft nonunion reconstruction: Can the lateral paratricipital approach prevent this common complication?

BackgroundPostoperative radial nerve palsy (RNP) is a well-known complication of nonunion reconstruction of the humerus. The purpose of the current study is to determine if the surgical approach for nonunion reconstruction of the humerus influences the rate of postoperative radial nerve palsy. MethodsA retrospective case-control study of all humeral shaft and extraarticular distal humerus nonunion reconstructions performed between January 1, 2004, and August 31, 2021, was conducted. Patients included were over 18 years of age, had a non-pathologic humerus fracture nonunion and had intact radial nerve function prior to nonunion reconstruction. Exclusion criteria consisted of nonunions involving the proximal humerus, intraarticular fractures, and reconstructive treatment procedures with either intramedullary nail or external fixation methods. Perioperative variables were recorded and analyzed in regard to the development of postoperative RNP. A subgroup analysis was performed to assess the interaction of significant variables on the development of postoperative RNP. ResultsThe overall rate of postoperative RNP in this series was 6/53 (11%). However, no cases of postoperative radial nerve palsy were observed in patients who underwent nonunion reconstruction with a lateral paratricipital approach. A new RNP was seen in 4/9 (44%) of those patients who underwent a triceps splitting approach, which was significantly higher than those utilizing either an anterolateral approach (2/28, 7%) or a lateral paratricipital approach (0/16, 0%, p = 0.007). Discussion and conclusionOur data suggests that the lateral paratricipital exposure decreases the risk of radial nerve injury with nonunion reconstruction of the humerus. The lateral paratricipital exposure offers the benefit of radial nerve exploration, decompression, neurolysis and protection prior to fracture manipulation and instrumentation. This study shows conventional approaches may predispose patients to a high rate of postoperative RNP, similar to that in the literature.

Apex of Triceps Aponeurosis: A Reliable Landmark to Localize the Radial Nerve.

The patient is anesthetized and placed in the lateral decubitus position with the elbow of the operative limb hanging freely over a bolster. A posterior midline incision centered over the fracture is made on the posterior aspect of the arm. The superficial and deep fascia are incised. The triceps aponeurosis is formed by the convergence and fusion of the lateral and long heads of the triceps. The most proximal confluence can be termed the "apex of the triceps aponeurosis." The radial nerve can be isolated approximately 2.5 cm proximal to the apex by developing an intramuscular plane. The remainder of the intramuscular dissection for plate fixation can then be performed safely without risking injury to the radial nerve. Numerous studies have established the relationship of the radial nerve to a fixed osseous point such as the medial epicondyle, lateral epicondyle, and angle of the acromion4-9. Additionally, the wide range of measurements of these anatomic relationships, as reported in various studies, makes it difficult for the operating surgeon to locate the radial nerve, especially in the setting of a fractured humeral shaft. For example, the reported distance of the radial nerve from the lateral epicondyle ranges from 6 to 16 cm and the distance from the angle of the acromion ranges from 10 to 19 cm. Even identification of the superficial branch of the radial nerve has been shown to help intraoperative localization of the radial nerve10. However, these studies have been conducted on cadavers with intact humeri, and their accuracy has not been demonstrated on the patients in the clinical milieu of trauma. The described soft-tissue landmark, which lies approximately 2.5 cm proximal to the apex of the triceps aponeurosis, reliably locates the radial nerve intraoperatively11. It is based on the anatomical fact that the origins of the lateral head (oblique ridge corresponding to the lateral lip of the spiral groove) and long head (infraglenoid tubercle of the scapula) are well above fractures of the middle and distal thirds of the humerus. Hence, the relationship of the radial nerve to the soft point represented by the apex of the aponeurosis is not likely to be disturbed in the setting of fractures distal to it, in sharp contrast with previously described osseous landmarks. Employing this anatomical understanding resulted in early localization of the radial nerve (within 6 ± 1.5 minutes of skin incision) and less blood loss (188 ± 13 mL)11. Patients are likely to retain their ability to perform active dorsiflexion of the wrist and fingers and have sensory preservation in the distribution of autonomous zone of the radial nerve after the procedure. The relationship of the radial nerve to the soft point represented by the apex of the aponeurosis is not likely to be disturbed in the setting of typical fractures distal to it; however, this may differ in cases of severely displaced or comminuted fractures, and the surgeon should be aware of this fact.The surgeon should remain careful to protect the vena comitans.

Primary radial nerve palsy associated with humeral shaft fractures according to injury mechanism: is early exploration needed?

Radial nerve palsy is a common complication associated with humeral shaft fractures. The purposes of this study were (1) to evaluate the status of primary radial nerve palsy in patients with humeral shaft fracture according to injury mechanism, (2) to estimate the risk factors of primary RNP, and (3) to evaluate whether early exploration is helpful for radial nerve recovery. This study analyzed 162 patients with humeral shaft fractures from January 2014 to December 2019. All patients were surgically treated in our hospital. Of these, 109 high-energy injuries were identified and compared with 53 low-energy injuries. The risk factors of radial nerve palsy were analyzed, and the prevalence of radial nerve palsy and status of radial nerve exploration according to injury mechanism were evaluated. Nerve recovery rate according to early nerve exploration was investigated. There were 31 cases of radial nerve palsy among 162 patients: 27 in the high-energy humeral shaft fracture group and 4 in the low-energy humeral shaft fracture group. Logistic regression analysis for risk factors showed that the injury mechanism was significantly associated with primary radial nerve palsy. Among 31 radial nerve palsy patients, 21 radial nerves were explored and 19 radial nerves recovered completely (80.6%). In the high-energy humeral shaft fracture group, 18 radial nerves were explored during surgery among 27 radial nerve palsy cases, and 16 cases recovered (88.9%). The other 9 radial nerves were not explored, and only 5 cases recovered (55.6%). This study confirmed that the incidence of radial nerve paralysis was higher in high-energy humeral shaft fractures than in low-energy fractures. The more common fracture patterns were oblique, transverse, wedge, and comminuted in high-energy humeral shaft fracture. This study suggests that these patterns are not directly associated with radial nerve palsy, but that high-energy injury is associated with a specific fracture pattern. Early nerve exploration during surgical treatment in patients with radial nerve palsy associated with humeral shaft fracture was helpful especially after high-energy injury.

Epidemiological, clinical, and electrophysiological findings in dogs and cats with traumatic brachial plexus injury: A retrospective study of 226 cases.

BackgroundThe imaging and electrodiagnostic (EDX) characteristics of traumatic brachial plexus injury (TBPI) are incompletely reported.ObjectivesTo describe the epidemiological, clinical, and EDX characteristics of TBPIs in a series of cases in dogs and cats; to determine the association between clinical data, EDX findings, and clinical outcomes; and to assess the sensitivity and specificity of EDX studies to classify nerve lesions.AnimalsOne hundred and seventy‐five dogs and 51 cats with TBPI and EDX exploration of radial nerve, ulnar nerve, or both nerves.MethodsRetrospective case series. All medical records were searched for dogs and cats presenting with TBPIs that underwent EDX exploration. Epidemiological, clinical, EDX, and follow‐up data were extracted. Association between clinical data, EDX findings, and clinical outcomes was explored.ResultsForty‐six percent of affected animals were injured before 2 years of age and 57% of dogs weighed more than 20 kg. The radial compound muscle action potential (CMAP) amplitude for dogs and cats that had clinical improvement was higher than in animals without improvement (4.3 mV [0‐23.6] vs 0 mV [0‐2.4], respectively, P = .02). A discriminating radial CMAP amplitude threshold value of 5 mV had a specificity of 93% (95% CI [80‐100]) to predict recovery.Conclusions and Clinical ImportanceElectrodiagnostic studies, particularly measurement of radial CMAP amplitude, are valuable diagnostic tests to refine the prognosis of these animals.

Radial nerve recovery following closed nailing of humeral shaft fractures without radial nerve exploration: A retrospective study.

BACKGROUNDRadial nerve palsy due to humeral shaft fracture is the most common peripheral nerve injury associated with long bone fractures. An antegrade nailing surgical technique is becoming popular for the fixation of these fractures with minimal invasiveness. We analyzed nerve recovery in patients with humeral shaft fracture and radial nerve palsy treated with humeral nail fixation without nerve exploration.AIMTo assess the radial nerve recovery rate and time from humeral shaft fracture with surgical treatment using close nailing.METHODSWe retrospectively collected data of patients who underwent undergone surgical nail fixation for humeral shaft fractures between October 1, 2016, and March 31, 2020. Subsequently, we analyzed the primary or secondary radial nerve palsy recovery rate and radial nerve motor function recovery time.RESULTSThe study included 70 patients who underwent surgical treatment for closed- or Gustilo type I open humeral shaft fractures using a nail fixation technique without radial nerve exploration. The patients suffered from primary (n = 5) and secondary (n = 5) radial nerve palsy. A 100% radial nerve recovery rate was achieved. The mean recovery time was 4.3 mo.CONCLUSIONThe study results indicate full recovery of radial nerve palsies from humeral shaft fracture using close nailing treatment. Surgeons need not be concerned about the occurrence of permanent nerve palsies.

The standardized exploration of the radial nerve during humeral shaft fixation reduces the incidence of iatrogenic palsy.

The purpose of this study is to determine if a standardized protocol for radial nerve handling during humeral shaft repair reduces the incidence of iatrogenic nerve palsy post operatively. Seventy-three patients were identified who underwent acute or reconstructive humeral shaft repair with radial nerve exploration as part of the primary procedure for either humeral shaft fracture or nonunion. All patients exhibited intact radial nerve function pre-operatively. A retrospective chart review and analysis identified patients who developed a secondary radial nerve palsy post-operatively. In each case, the radial nerve was identified and mobilized for protection, regardless of whether the implant necessitated the extensile exposure. Fractures were classified according to AO/OTA guidelines and included 23 Type 12A, 11 Type 12B, and 3 Type 12C. Eight patients had periprosthetic fractures and 28 fractures could not be classified. All patients in the cohort were fixed with locking plates. Surgery was indicated for 36 patients with humeral nonunions and 37 patients with acute humeral shaft fractures. Of the 73 patients, 2 (2.7%) developed radial nerve palsy following surgery, one from the posterior approach and one from the anterolateral approach. Both patients exhibited complete recovery of radial nerve function by 6-month follow-up. No significant differences (p > 0.05) were found in any demographic or surgical details between those with and without radial nerve injury. Nerve exploration identification and protection leads to a low incidence of transient radial nerve palsy compared to the rate reported in the current literature (2.7% compared to 6-24%). Thus, radial nerve exploration and mobilization should be considered when approaching the humeral shaft for acute fracture and nonunion repairs. Level III.

Primary Radial Nerve Exploration Determined by Ultrasound in Pediatric Supracondylar Humerus Fracture: A Report of Two Cases

We report two pediatric cases of radial nerve palsy caused by supracondylar fracture of the humerus requiring nerve exploration. The children had comparable conditions, palsy types (complete motor and partial sensory) and radiographic findings. The fracture in the first case was managed conservatively with closed reduction and percutaneous pinning but, while the patient eventually recovered from the partial sensory palsy, her motor palsy remained unchanged. In the second case, ultrasound assessment of the nerve prior to fixation indicated that surgical exploration was needed as it revealed tethering on the edge of the proximal fracture fragment. The nerve was released during an open reduction and the patient subsequently recovered from both sensory and motor palsies. Ultrasonography proved essential in the initial clinical assessment by determining how to proceed. We recommend primary nerve exploration when ultrasound findings show entrapment or tethering of the radial nerve.

Incidence and Management of Radial Nerve Palsies in Humeral Shaft Fractures: A Systematic Review.

Radial nerve palsies in closed humeral shaft fractures are common, with an incidence of 7%-17%. The management of radial nerve palsies in closed fractures is often expectant, with 70.7% spontaneously recovering within six months. A literature search was conducted for studies on radial nerve palsies in humeral shaft fractures from 2000-2018. A total of 4972 humeral shaft fractures were identified, with an incidence of 12.2% of primary radial nerve palsies. During the exploration, no neurological intervention was performed in nearly 41% of cases, and the most common finding was no evidence of any nerve lesion (35%). Those who underwent neurolysis were more likely to resolve when compared to primary repair or nerve grafting. Overall, there was a high rate of spontaneous radial nerve palsy recovery (85%) with radial nerve exploration increasing rates of resolution. While exploration demonstrates increased resolution, it is yet to be determined which fractures are indicated for nerve exploration.

Need for early exploration of radial nerve in humeral shaft fractures with radial nerve palsy.

Radial nerve palsy (RNP) associated with humeral shaft fracture (HSF) is the most common nerve complication in long bone fractures. There is still controversy over the need for immediate exploration of the radial nerve (RN) in HSF with RNP. The purpose of the current study was to determine which situations of HSF with RNP require early exploration of the RN. This is a retrospective study that included 55 patients who had visited the emergency department of the current authors' hospital and had been diagnosed with HSF between March of 2005 and September of 2015. Of these 55 patients, 14 (25.4%) had been diagnosed with HSF with RNP. We reviewed the medical records of those 14 patients and their radiographs to evaluate each fracture's type, location, pattern, energy of trauma, status of RN injury, and time until recovery from RNP. All the 14 RNP patients had suffered high-energy trauma. Three had fractures in the proximal third (21.4%), six in the middle third (42.9%), and five in the distal third (35.7%). The three patients (21.4%) with incomplete recovery of RNP all had proximal third fractures; two of these three patients had RN transection. Early exploration of the radial nerve should be considered in patients with radial nerve palsy associated with proximal third humeral shaft fracture, regardless of the fracture patterns caused by the high-energy trauma.

Effectiveness of ultrasonographic evaluation under general anesthesia for radial nerve palsy associated with humeral fractures during the first operation.

To evaluate the effectiveness of sonographic evaluation of the radial nerve at the first operation for closed humeral fracture cases. Seventeen cases of closed humeral fractures were included in this study. These cases were categorized into two groups: Group P, consisting of seven cases with complete radial nerve palsy after the injuries; and Group C, consisting of ten cases without radial nerve palsy after the injuries. Sonographic evaluation of the condition of the radial nerve was performed before or after open or closed reduction and internal fixation (ORIF or CRIF) during the first operation. Five of seven Query ID="Q2" Text=" As keywords are mandatory for this journal, please provide 3-6 keywords." cases in Group P showed entrapment or compression of the radial nerve at fracture sites with sonography. Simultaneous radial nerve exploration (SRNE) confirmed sonographic findings in these five cases. The other two cases showed no abnormal sonographic findings except swelling of the radial nerve. CLIF without SRNE was selected and additional sonographic reevaluation of the nerve after CRIF confirmed there were no iatrogenic nerve injuries in these two cases. All of the ten cases in Group C showed no abnormal sonographic findings of the radial nerve. Five of these ten cases selected ORIF, exposed the nerve at the time of approaching the fracture site, and matched sonographic findings. The other five cases without exposure of the nerve confirmed no iatrogenic radial nerve injuries with additional sonographic reevaluation after ORIF or CRIF. All cases in Group P had complete resolution of radial nerve palsy within 4months postoperatively, and no case in Group C had postoperative iatrogenic radial nerve palsy. Sonographic evaluation of the radial nerve at the first operation was a useful method to detect conditions of the nerve which can prevent compression or entrapment of the nerve and the need for secondary nerve exploration.

Lateral condylar retrograde humeral nail for management of high-energy distal humeral fractures.

Distal metaphyseo-diaphyseal humeral fractures are challenging particularly if open, comminuted, or associated with nerve injury. In cases of open distal complex metaphyseo-diaphyseal humeral fractures inamenable for traditional methods of fixation, retrograde intramedullary locked humeral nail with a new lateral condylar point of entry has been proposed. Two phases of study were conducted; phase I comprised computerized tomography evaluation of right humeri of 120 adult subjects, while phase II entailed prospective analysis of 18 patients who sustained firearm injuries resulting in open distal metaphyseo-diaphyseal humeral fractures associated with radial nerve injuries. All patients were surgically managed using lateral condylar retrograde humeral nailing with primary radial nerve exploration. Distal sagittal medullary diameter of the humeral medulla was the narrowest in comparison to axial and coronal medullary diameters in phase II, which matched the results of phase I. The mean postoperative disability of the arm, shoulder, and hand score was 11.2 ± 6.4. Only five patients underwent subsequent successful tendon transfer. Lateral condylar retrograde humeral nail with early radial nerve exploration in cases of high-energy distal metaphyseo-diaphyseal humeral fractures yielded good results regarding union and spontaneous radial nerve recovery or later on reconstruction.

A new approach for surgical treatment of chronic Monteggia fracture in children

PurposeThe aim of the study was to investigate the clinical outcomes of a combined anterior and posterior approach for the surgical treatment of chronic Monteggia fractures in children. Materials and methodsFrom November 2010 to January 2018, 33 patients (27 boys and 6 girls) with chronic Monteggia fracture who were treated surgically by one surgeon of our department were retrospectively analyzed. In the surgical procedure, open reduction and excision of fibrous scar were performed with the anterior Henry’s approach, while ulnar osteotomy was carried out with a posterior approach. In cases of unstable radial head reduction, a trans-capitellar K wire was applied. Repair or reconstruction of the annular ligament (ALR) was not undertaken. ResultsThe average follow-up of the patients was 33.8 months (range 8–87 months). At the last follow-up, Mayor Score and function of flexion and extension showed significant improvement compared to preoperative condition (p < 0.05). Two patients with palsy of the deep branch of the radial nerve with neurolysis recovered to normal over a 3-month follow-up. Redislocation occurred in two patients while subluxation occurred in one. One patient suffered a mild ischemic contracture but gradually recovered. Other severe complications, nerve injuries, heterotopic ossification, or synostosis, were not noted in the follow-up. ConclusionA combined anterior and posterior approach for surgery resulted in a satisfactory outcome due to the advantages of better exposure, more convenient intraoperative management, and facilitate for radial nerve exploration. Our study provided a new approach for the surgery of chronic Monteggia fractures.

Final outcomes of radial nerve palsy associated with humeral shaft fracture and nonunion

BackgroundLittle evidence regarding the extent of recovery of radial nerve lesions with associated humerus trauma exists. The aim of this study is to examine the incidence and resolution of types of radial nerve palsy (RNP) in operative and nonoperative humeral shaft fracture populations.Materials and MethodsRadial nerve lesions were identified as complete (RNPc), which included motor and sensory loss, and incomplete (RNPi), which included sensory-only lesions. Charts were reviewed for treatment type, radial nerve status, RNP resolution time, and follow-up time. Descriptive statistics were used to document incidence of RNP and time to resolution. Independent-samples t-test was used to determine significant differences between RNP resolution time in operative and nonoperative cohorts.ResultsA total of 175 patients (77 operative, 98 nonoperative) with diaphyseal humeral shaft injury between 2007 and 2016 were identified and treated. Seventeen out of 77 (22.1%) patients treated operatively were diagnosed preoperatively with a radial nerve lesion. Two (2.6%) patients developed secondary RNPc postoperatively. Eight out of 98 (8.2%) patients presented with RNP postinjury for nonoperatively treated humeral shaft fracture. All patients who presented with either RNPc, RNPi, or iatrogenic RNP had complete resolution of their RNP. No statistically significant difference was found in recovery time when comparing the operative versus nonoperative RNPc, operative versus nonoperative RNPi, or RNPc versus RNPi patient groups.ConclusionsAll 27 (100%) patients presenting with or developing radial nerve palsy in our study recovered. No patient required further surgery for radial nerve palsy. Radial nerve exploration in conjunction with open reduction and internal fixation (ORIF) appears to facilitate speedier resolution of RNP when directly compared with observation in nonoperative cases, although not statistically significantly so. These findings provide surgeons valuable information they can share with patients who sustain radial nerve injury with associated humerus shaft fracture or nonunion.Level of evidenceLevel III treatment study.

Antero-lateral minimally invasive plate osteosynthesis (MIPO) with the radial nerve exploration for extra-articular distal-third diaphyseal fractures of the humerus.

Traditional open reduction and internal fixation (ORIF) of extra-articular distal humerus fractures has a risk of iatrogenic radial nerve injury, extensive soft tissue stripping, and long incision scar. We performed an antero-lateral minimally invasive plate osteosynthesis (MIPO) technique with the radial nerve exploration for distal-third diaphyseal fractures of the humerus and evaluated clinical and radiographic outcomes through this respective study. From April 2010 to June 2016, 28 cases of extra-articular distal-third diaphyseal fractures were treated with an antero-lateral MIPO procedure. Patient demographics, Disabilities of the Arm, Shoulder and Hand (DASH) Score, Mayo Elbow Performance (MEP) Score, elbow range of motion, scars and post-operative complications were recorded and analyzed. All fractures were united with a mean time of 3.5months. One patient exhibited delayed union (3.6%). The mean DASH Score was 6.6, and all patients had excellent or good MEP Score values. The average scar length was 6.8cm, and the shortest was 4.5cm. The MIPO technique via an antero-lateral approach for extra-articular distal-third diaphyseal fractures of the humerus results in satisfactory clinical outcomes. Level IV, case series, treatment study.

Predictors of radial nerve palsy recovery in humeral shaft fractures: A retrospective review of 17 patients

BackgroundRadial nerve injury is common in humeral shaft fractures and fails to recover spontaneously in 30% of cases. Few studies have evaluated predictors of recovery. The objectives of this study were to identify predictors of radial nerve palsy recovery and to assess the usefulness of surgical radial nerve exploration in patients with preoperative radial nerve palsy. HypothesisFactors predicting the outcome of radial nerve palsy can be identified. MethodsOf 373 patients with humeral shaft fractures between 2005 and 2012, 43 had radial nerve palsy, including 23 who were lost to follow-up and 17 who were evaluated retrospectively at a mean of 26 months (range, 12–84 months) after internal fixation. The following were studied: age, smoking history, energy of the trauma, fracture type and displacement, skin integrity and intra-operative appearance of the radial nerve. ResultsOf the 17 palsies, 13 were present preoperatively, including 10 that recovered (PreR group) and 3 that did not recover (PreNR group). Plate fixation and radial nerve exploration were performed in all patients. Of the 10 PreR patients, 6 had nerve contusion and 2-nerve entrapment. Of the 3 PreNR patients, 2 had gross nerve damage and 1 nerve contusion and a history of spinal muscular atrophy. Only age and presence of gross nerve damage differed significantly between the PreR and PreNR groups; trends towards significant differences were noted for skin breach and fracture displacement. Of the 4 postoperative radial nerve palsies, 2 recovered fully and 2 partially; mean age was higher in the 2 patients with partial recovery. DiscussionThese findings are consistent with the few previous studies of outcome predictors in radial nerve palsy. Factors such as major fracture displacement and high-grade skin wounds probably promote the occurrence of gross nerve lesions. The high incidence of nerve entrapment and stretching supports routine nerve exploration during internal fixation in patients with preoperative radial nerve palsy. Level of evidenceIV, retrospective study with no control group.