Superficial Branch of the Radial Nerve Versus Sural Nerve Grafting After Traumatic Adult Brachial Plexus Injury.

The purpose of this study was to compare two sources of nerve graft for brachial plexus reconstruction: the denervated superficial branch of the radial nerve (SBRN) and the sural nerve. Ninety-seven patients who underwent brachial plexus reconstruction with denervated SBRN nerve (24 patients with 24 grafts) or with sural nerve grafting (73 patients with 83 nerve grafts) were included. The two groups were compared with respect to postoperative muscle reinnervation, disabilities of the arm, shoulder, and hand (DASH) scores. In the SBRN group, only four (17%) of the nerve grafts provided grade III or higher muscle function. In the sural nerve group, 31 (37%) of the nerve grafts provided grade III or higher muscle function. Smoking had a negative impact on muscle recovery. Denervated SBRN grafts are associated with inferior outcomes when compared with sural nerve grafts in the treatment of traumatic adult brachial plexus injuries. (Journal of Surgical Orthopaedic Advances 33(2):080-083, 2024).

Systematic review of humeral shaft fracture (OTA/AO 12) complicated with iatrogenic radial nerve injury.

OBJECTIVES: To compare the iatrogenic radial nerve injury (iRNI) rate of different implant (plate vs. intramedullary nail) and surgical approaches during humeral shaft fracture surgery. METHODS: The online PubMed database was used to search for articles describing iRNI after humeral fracture with a publication date from Jan 2000 to October 2023. The following types of articles were selected: (1) case series associating with adult humeral shaft fracture, preoperative radial nerve continuity, non-pathological fracture and non-periprosthetic fracture; (2) involving humeral shaft (OTA/AO 12) fractures. Articles where we were unable to judge surgical approach or fracture pattern (OTA/AO 12) were excluded. The data were analyzed by SPSS 27.0 and Chi-square test was performed to identify incidence of iRNI associated with different implant and surgical approaches. RESULTS: Fifty-four articles with 5063 cases were included, with 3510 cases of the plate, 830 cases of intramedullary nail and 723 cases of uncertain internal fixation. The incidences of iRNI with plate and intramedullary nail were 5.95% (209/3510) and 2.77% (23/830) (p < 0.05). And iRNI incidences of different surgical approaches were 3.7% (3/82) for deltopectoral approach, 5.74% (76/1323) for anterolateral approach, 13.54% (26/192) for lateral approach and 6.68% (50/749) for posterior approach. The iRNI rates were 0.00% (0/33) for anteromedial MIPO, 2.67% (10/374) for anterolateral MIPO and 5.40% (2/37) for posterior MIPO (p > 0.05). The iRNI rates were 2.87% (21/732) for anterograde intramedullary nail and 2.04% (2/98) for retrograde intramedullary nail (p > 0.05). In humeral bone nonunion surgery, the rate of iRNI was 15.00% (9/60) for anterolateral approach, 16.7% (2/12) for lateral approach and 18.2% (6/33) for posterior approach (p > 0.05). CONCLUSION: Intramedullary nailing is the preferred method of internal fixation for humeral shaft fractures that has the lowest rate of iRNI. Compared with anterolateral and posterior approaches, the lateral surgical approach had a higher incidence of iRNI. The rate of iRNI in MIPO was lower than that in open reduction and internal fixation. LEVEL OF EVIDENCE: Level IV.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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 Nerve Palsy in the Setting of Humeral Shaft Fracture.

The upper limb has a complex anatomy comprised of many nerve and vascular structures, making humeral shaft fractures extremely important. Injury to the humeral shaft commonly occurs due to trauma and affects younger male or older female patients. The radial nerve travels along the spiral groove of the humerus, placing it at an increased risk of damage in humeral shaft fractures. If injured, there are a variety of classifications of radial nerve injury, different indications for exploration, and treatment methods that orthopedic surgeons have available in treating these injuries. This review aims to discuss the etiology of humeral shaft fracture-associated radial nerve palsy, tools for diagnosis, and treatment.

Radial neuropathy.

Radial neuropathy is the third most common upper limb mononeuropathy after median and ulnar neuropathies. Muscle weakness, particularly wrist drop, is the main clinical feature of most cases of radial neuropathy, and an understanding of the radial nerve's anatomy generally makes localizing the lesion straightforward. Electrodiagnosis can help confirm a diagnosis of radial neuropathy and may help with more precise localization of the lesion. Nerve imaging with ultrasound or magnetic resonance neurography is increasingly used in diagnosis and is important in patients lacking a history of major arm or shoulder trauma. Radial neuropathy most often occurs in the setting of trauma, although many other uncommon causes have been described. With traumatic lesions, the prognosis for recovery is generally good, and for patients with persistent deficits, rehabilitation and surgical techniques may allow substantial functional improvement.

Timing of surgery in peripheral nerve injury of the upper extremity.

Peripheral nerve injuries present a complex clinical challenge, requiring a nuanced approach in surgical management. The consequences of injury vary, with sometimes severe disability, and a risk of lifelong pain for the individual. For late management, the choice of surgical techniques available range from neurolysis and nerve grafting to tendon and nerve transfers. The choice of technique utilized demands an in-depth understanding of the anatomy, patient demographics and the time elapsed since injury for optimized outcomes. This paper focuses on injuries to the radial, median and ulnar nerves, outlining the authors' approach to these injuries.Level of evidence: IV.

[Secondary surgical procedures following motor nerve injuries]. / Sekundäre operative Verfahren bei Verletzungen motorischer Nerven.

BACKGROUND: The functional deficits that develop after a peripheral nerve injury mean a considerable reduction in the quality of life for the affected patients. However, interventions on the injured nerve are not always possible or effective. In this case, secondary procedures, e.g. tendon transfers, are a feasible option for functional reconstruction. OBJECTIVES: An overview of the most common secondary surgical procedures for functional reconstruction after peripheral nerve injuries. METHODS: Presentation and discussion of the most common secondary surgical procedures with emphasis on tendon transfers. Illustration of the primary functions that need to be reconstructed depending on the respective nerve lesion. RESULTS: The basic principle of secondary surgical procedures after nerve injuries is the transposition of a healthy tendomuscular unit to replace a lost function following a loss of muscle or tendon or if an intervention on the nerve is not promising. For example, by transferring flexor forearm muscles, wrist, finger and thumb extension can be reconstructed after radial nerve injury. By transposing the tibialis posterior muscle, dorsiflexion in the talocrural joint can be restored to enable the affected patient to walk safely without an orthosis. CONCLUSIONS: Secondary surgical procedures are a valuable option for functional reconstruction after nerve injury.

Radial nerve lesion after medial epicondyle osteosynthesis in a pediatric patient: A rare complication of surgery.

Fractures of the medial epicondyle are relatively common in children and may be associated with nerve lesion, especially in case of displacement. Incarceration of the ulnar nerve in the fracture site is feared in Watson-Jones stage II, rarely directly related to osteosynthesis. Depending on the degree of fracture displacement, various osteosynthesis techniques may be used; nerve injuries are a rare but known complication of these procedures. We report a case of radial nerve injury related to pinning osteosynthesis of a medial epicondyle fracture.

Anatomic consideration of the radial nerve in relation to humeral length for unilateral external fixation: a retrospective study using magnetic resonance imaging findings in korean.

BACKGROUND: This study aimed to present a safe zone for distal pin insertion for external fixation using magnetic resonance imaging (MRI) images. METHODS: All patients who took at least one upper arm MRI from June 2003 to July 2021 were searched via a clinical data warehouse. For measuring the humerus length, proximal and distal landmarks were set as the highest protruding point of the humeral head and lowermost margin of ossified bone of the lateral condyle, respectively. For children or adolescents with incomplete ossification, the uppermost and lowermost ossified margin of the ossification centers were set as proximal and distal landmarks respectively. The anterior exit point (AEP) was defined as the location of the radial nerve exiting the lateral intermuscular septum to the anterior humerus and distance between the distal margin of the humerus and AEP was measured. The proportions between the AEP and full humeral length were calculated. RESULTS: A total of 132 patients were enrolled for final analysis. The mean humerus length was 29.4 cm (range 12.9-34.6 cm). The mean distance between the ossified lateral condyle and AEP was 6.6 cm (range 3.0-10.6 cm). The mean ratio of the anterior exit point and humeral length was 22.5% (range 15.1-30.8%). The minimum ratio was 15.1%. CONCLUSION: A percutaneous distal pin insertion for humeral lengthening with an external fixator may be safely done within 15% length of the distal humerus. If pin insertion is required more proximal than distal 15% of the humeral shaft, an open procedure or preoperative radiographic assessment is advised to prevent iatrogenic radial nerve injury.

Outcomes and prognostic factors for nerve grafting following high radial nerve injury.

In this study, we examined the prognostic factors affecting outcomes following nerve grafting in high radial nerve injuries. Thirty-three patients with radial nerve injuries at a level distal to the first branch to the triceps and proximal to the posterior interosseous nerve were retrospectively studied. After a follow-up of at least 1 year, 24 patients (73%) obtained M3+ wrist extension, 16 (48%) obtained M3+ finger extension and only ten (30%) obtained M3+ thumb extension. Univariate, multivariate and receiver operating characteristic analyses showed that a delay in the repair of less than 6 months, a defect length of less than 5 cm or when grafted with three or more donor nerve cables achieved better recovery. Number of cables used was related to muscle strength recovery but not time to reinnervation. Nerve grafting for high radial nerve injury achieved relatively good wrist extension but poor thumb extension and is affected by certain prognostic factors. Level of evidence: IV.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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 OF EVIDENCE: Level III.

Anatomical variations in the sensory innervation of the dorsal surface of the first digit space, a cadaveric study with clinical consequences.

INTRODUCTION: Radial nerve palsy is a classical complication of a humeral shaft fracture. In clinical practice, motor palsy of the radial nerve is sometimes observed without an abnormality felt in the sensory territory. HYPOTHESIS: We hypothesised that this dissociation between sensory and motor involvement is related to anatomical variations of the sensory innervation of the dorsal surface of the first digit space, thus, we decided to study the nature and frequency of these variations. MATERIAL AND METHOD: A cadaveric study was conducted on 24 upper limbs to analyse the truncal origin of the sensory branches innervating the dorsal surface of the first digit space. RESULTS: The sensory branch of the radial nerve (SBRN) participated in the innervation of the dorsal surface of the first digit space in 22 limbs, an anatomical variation was present in 2 cases with a mixed innervation by the SBRN and the lateral cutaneous nerve of forearm (LCNF) in 1 case and singular innervation by LCNF, with no SBRN involvement, in 1 case. Communications between SBRN and LCNF were found in 7 cases. DISCUSSION: Pure motor radial damage, without a sensory deficit of the dorsal surface of the first digit space, does not preclude a complete traumatic injury of the radial nerve. The sensory innervation of this region can be relayed by a branch of the LCNF. LEVEL OF EVIDENCE: IV; cadaveric study.

[Reconstruction of painful neuroma of superficial branch of radial nerve after first dorsal compartment release: presentation of two cases]. / Reconstrucción de neuroma de nervio radial superficial con injerto autólogo de nervio sural: presentación de dos casos.

INTRODUCTION: nerve lesions are potentially catastrophic injuries. They can cause motor loss, severe pain and neuroma formation. The superficial branch of the radial nerve is at risk during first dorsal compartment release, its injury can cause neuroma formation. Autologous nerve reconstruction is the gold standard for treatment of small nerve gaps. CASES PRESENTATION: we present two cases of adult women (F/47 y F/51) with a prior history of first dorsal compartment release in another institution. Both patients developed debilitating neuropathic pain, as well as allodynia in the surgical site. They were diagnosed with superficial radial nerve neuroma. Oral medication and physical therapy was attempted without success. Surgical exploration and autologous nerve reconstruction was performed. Both patients had excellent relief of pain from visual analogue scale (VAS 9-10 to VAS 1-2). Postoperatively, both patients recovered partial sensitivity to pain in the zones distal to the repair. CONCLUSIONS: neuromas are feared complications that occur with unrecognized nerve lesions during surgery, they are difficult to treat and require multidisciplinary management. These two cases demonstrate that autologous nerve reconstruction is an excellent option for recovering function in small gaps of nerve tissue.

INTRODUCCIÓN: las lesiones iatrogénicas de nervio son complicaciones devastadoras de cualquier procedimiento quirúrgico. Ocasionan pérdida motora, dolor y formación de neuromas. En el abordaje para la liberación del primer compartimiento extensor de la muñeca, la rama superficial del nervio radial debe identificarse y protegerse previo a la liberación tendinosa. La lesión de este nervio sensitivo puede ocasionar dolor postoperatorio clínicamente significativo. La reconstrucción nerviosa con nervio autólogo ha demostrado en diversos escenarios buenos resultados para mejorar el dolor y recuperar la conducción nerviosa. PRESENTACIÓN DE LOS CASOS: se presentan dos casos de mujeres adultas (F/47 y F/51) con antecedente de liberación de primer compartimiento dorsal de muñeca en otro centro hospitalario. Desarrollaron posteriormente dolor incapacitante y alodinia en sitio quirúrgico, así como limitación funcional. Fueron evaluadas y diagnosticadas como neuroma de rama superficial del nervio radial. No hubo mejoría con terapia física, por lo que se realizó reconstrucción nerviosa con injerto autólogo de nervio sural. Ambas pacientes tuvieron alivio del dolor de EVA 9-10 hasta EVA 1-2. A los cuatro meses de seguimiento, las dos mujeres recuperaron parcialmente la sensibilidad distal al sitio del neuroma, sin recurrencia del dolor presentado. CONCLUSIONES: los neuromas son complicaciones devastadoras que ocurren con lesiones inadvertidas de nervios motores y sensitivos. La reconstrucción con nervio autólogo es una excelente opción para reconstrucción de pequeños tramos de nervio periférico.

Lesiones iatrogénicas del nervio radial en la osteosíntesis de la diáfisis humeral / Intraoperative iatrogenic injury of the radial nerve in humerus osteosynthesis

Introducción: Los objetivos de este estudio fueron determinar la incidencia de lesión iatrogénica intraquirúrgica del nervio radial durante la osteosíntesis de la diáfisis y el extremo distal del húmero, distinguir factores de riesgos asociados y reconocer elementos pronósticos que participan de su recuperación. Materiales y Métodos: Se evaluó, en forma retrospectiva, a 82 pacientes con osteosíntesis de húmero entre 2005 y 2021, sin parálisis radial preoperatoria. Se consideraron los sistemas de fijación utilizados, y se compararon las cirugías primarias con las reoperaciones y el tiempo transcurrido entre estas. El diagnóstico de parálisis radial posoperatorio fue clínico. Todos los pacientes fueron tratados con férula en extensión de muñeca, electroestimulación, kinesiología y vitaminas B1, B6, B12. La electromiografía se solicitó a los fines del pronóstico. Resultados: Nueve pacientes tuvieron déficit motor del nervio radial en el posoperatorio inmediato. El sistema de fijación era una placa (7 casos), sistema de cable-placa (1 caso) y clavo endomedular acerrojado anterógrado (1 caso). Siete ocurrieron en cirugías primarias y dos en reoperaciones. El 88% recuperó su función motora completamente antes de los 6 meses después de la parálisis. La electromiografía reveló un nervio radial no excitable en el 22% restante con parálisis definitiva. Conclusiones: El uso de placa de osteosíntesis, la disección intraoperatoria del nervio radial y las reoperaciones aumentan la incidencia de parálisis. Un nervio radial no excitable se relaciona con un peor pronóstico de recuperación espontánea. Nivel de Evidencia: IV

Introduction: The purpose of this study is to determine the incidence of intraoperative iatrogenic radial nerve injury after osteosynthesis of the diaphysis and distal end of the humerus, identify associated risk factors, and determine the prognostic factors involved in its recovery. Materials and Methods: We retrospectively assessed 82 humerus osteosynthesis cases between 2005 and 2021 who had normal radial nerve function before surgery. We evaluated the fixation systems used, the type of surgery (primary versus revision), and the intervals between surgeries. The diagnosis of postoperative radial palsy was made by clinical examination. All patients were treated with wrist extension splint, physiotherapy, and vitamins B1, B6, and B12. Results: After humerus fixation, 9 patients developed motor palsy. Seven cases were fixed with plates, one with a cable-plate system, and one with an anterograde locking intramedullary nail. Seven cases (22%) occurred after primary procedures, while two occurred during revisions. Within 6 months, 88% had regained full motor function. In the remaining 22% of patients with definite palsy, electromyography revealed no excitability of the radial nerve. Conclusions: The use of an osteosynthesis plate, as well as intraoperative dissection and neurolysis of the radial nerve, were identified as risk factors for the development of radial palsy. Reoperations on the humerus, on the other hand, are a risk factor that increases the likelihood of postoperative radial nerve palsy. A radial nerve with no excitability on the postoperative electromyogram has a poor prognosis of spontaneous radial nerve function recovery. Level of Evidence: IV

Radial Nerve Injury In Patients With Closed Fracture Of Humerus Shaft In High Energy Trauma Cases.

Background: Fracture of the humerus usually result in radial nerve injury. This study was done with the aim to determine the incidence of Radial Nerve Injury in patients with closed fracture of the humerus shaft in high-energy trauma cases. Methods: This descriptive study was conducted in the Department of Orthopaedics and Emergency room, Ghurki Teaching Hospital, Lahore from January to December 2021 recruiting consecutive such patients. Standard ward protocol was followed to manage the patients initially including fracture stabilization and analgesia requirement. All the patients were carefully assessed to detect radial nerve injury. Data analysis was done through SPSS 26.0. Results: A total of 80 patients were included with the confirmed diagnosis of fracture of the humerus. There were 55(68.5%) males and 25(31.25%) females. The age range was 20 to 60 years and the mean age of males and females was 31.62±8.35 and 38.43±5.06 respectively with overall mean age±SD was 38.93±6.19. There were 32 (40%) cases of spiral fracture, 17 (21.25%) cases of transverse fracture, 16 (20%) cases of communized fracture, and 15 (18.75%) cases of segmental fracture. Radial nerve injury was present in 7 (8.75%) patients. Out of these 7 cases of radial nerve injury; 4 (57.1%) cases were recorded in patients with spiral closed fracture of midshaft of humerus, 1 (14.3%) cases were recorded in transverse closed fracture of humerus shaft, 1(14.3%) cases in comminuted closed fracture of midshaft of the humerus while 1 (14.3%) were segmental fractures. Conclusion: Our study highlighted the frequency of radial nerve palsy in humeral shaft cases with most common in spiral closed fracture of the midshaft of the humerus.

Treatment of Radial Nerve Palsy in Paediatric Humeral Shaft Fractures. STROBE-Compliant Investigation.

Background and Objectives:Due to the rarity of radial nerve palsy in humeral shaft fractures in the paediatric population and the lack of data in the literature, the purpose of our study was to report the treatment results of six children who sustained a radial nerve injury following a humeral shaft fracture. Materials and Methods: We treated six paediatric patients with radial nerve palsy caused by a humeral shaft fracture in our department from January 2011 to June 2022. The study group consisted of four boys and one girl aged 8.6 to 17.2 (average 13.6). The mean follow-up was 18.4 months. To present our results, we have used the STROBE protocol designed for retrospective observational studies. Results:We diagnosed two open and four closed humeral shaft fractures. Two simple transverse AO 12A3c; one simple oblique AO 12A2c; two simple spiral AO 12A1b/AO 12A1c and one intact wedge AO 12B2c were recognized. The humeral shaft was affected in the distal third five times and in the middle third one time. In our study group, we found two cases of neurotmesis; two entrapped nerves within the fracture; one stretched nerve over the bone fragments and one case of neuropraxia. We found restitution of the motor function in all cases. For all patients, extensor muscle strength was assessed on the grade M4 according to the BMRC scale (except for a patient with neuropraxia-M5). The differences in patients concerned the incomplete extension at the radiocarpal and metacarpophalangeal (MCP) joints. Conclusions: In our small case series, humeral shaft fractures complicated with radial nerve palsy are always challenging medical issues. In paediatric patients, we highly recommend an US examination where it is possible to be carried out to improve the system of decision making. Expectant observation with no nerve exploration is reasonable only in close fractures caused by low-energy trauma. Early surgical nerve exploration related with fracture stabilisation is highly recommended in fractures after high-energy trauma, especially in open fractures and where symptoms of nerve palsy appear at any stage of conservative treatment.

Pronator teres nerve branch transfer to the extensor carpi radialis brevis nerve branch for wrist extension reconstruction in proximal radial nerve injury following humeral shaft fractures.

BACKGROUND: Tendon and nerve transfers are used for functional reconstruction in cases of proximal radial nerve injury complicated by humeral fractures in patients who do not show functional recovery after primary nerve repair. The effectiveness of pronator teres (PT) nerve branch transfer to the extensor carpi radialis brevis (ERCB) nerve branch for wrist extension reconstruction was investigated and compared to the results of tendon transfer. METHODS: This study included 10 patients with proximal radial nerve injury, who did not show functional recovery after primary nerve repair at our hospital between April 2016 and May 2019. The nerve transfer procedure included PT nerve branch transfer to the ECRB nerve branch to restore wrist extension and the flexor carpi radialis (FCR) nerve branch to the posterior interosseous nerve (PIN) to restore thumb and finger extension. Tendon transfer procedures included PT transfer to the ECRB for wrist extension, FCR transfer to the extensor digitorum communis (EDC) for finger extension and palmaris longus (PL) transfer to the extensor pollicis longus (EPL) for thumb extension. RESULTS: Five patients recovered Medical Research Council grade M4 muscle strength in the ECRB and EPL in both tendon and nerve groups. Two patients recovered grade M3 strength and three patients recovered grade M4 strength in the EDC in the tendon transfer group, and all five patients recovered grade M4 strength in the EDC in the nerve transfer group. Limited wrist flexion was observed only in one patient in the tendon transfer group. CONCLUSION: PT nerve branch transfer to the ECRB nerve branch combined with FCR nerve branch transfer to PIN is a useful strategy for wrist and fingers extension reconstruction in patients with proximal radial nerve injuries.

Risk of Radial Nerve Injury in Anterolateral Humeral Shaft Plating.

PURPOSE: The purpose of this study was to evaluate and compare the risk of iatrogenic radial nerve injury between arm positionings of 45° and 60° abduction in anterolateral humeral plating using a 4.5-mm narrow dynamic compression plate. METHODS: Fifty-six humeri of cadavers in the supine position with 45° of arm abduction were exposed through the anterolateral approach. A hypothetical fracture line was marked at the middle of the humerus, and a precontoured ten-hole 4.5-mm narrow dynamic compression plate was applied and fixed to the anterolateral surface. After the fixation, the radial nerve was exposed through a triceps-splitting approach. Screws in contact with or which had penetrated the radial nerve were deemed to be injuries. Then, the screws and plate were removed, the arm changed to the 60° arm abduction position, and the steps of applying the plate and inserting the screws were followed as in the 45° arm abduction step. RESULTS: The screws which could potentially injure the radial nerve were those of the second to sixth screw holes in both the 45° and 60° of arm abduction positions. The incidences of iatrogenic radial nerve injury of the second to sixth screw holes in the 45° position were 5.36%, 39.29%, 80.36%, 60.71%, and 10.71%, respectively, and at the 60° position were 5.36%, 53.57%, 83.93%, 60.71%, and 7.14%, respectively. There were no statistically significant differences in risk of injury between the two positions in all screw holes (all P-values > 0.05). DISCUSSION: In anterolateral humeral shaft fixation, arm abduction position did not affect the risk of iatrogenic radial nerve injury, with the main risk from certain screw holes. The surgeon should be careful in screw insertion, especially at the fourth and fifth screw holes. LEVEL OF EVIDENCE: IV; cadaveric study.

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

BACKGROUND: Postoperative 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. METHODS: A 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. RESULTS: The 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 CONCLUSION: Our 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.