Modified paratricipital approach without mobilization of the ulnar nerve prevents postoperative ulnar neuropathy in distal humerus fractures.

BACKGROUND: In distal humerus fracture surgery, postoperative ulnar neuropathy is a common complication. The present study assessed the utility of the modified paratricipital approach for preventing ulnar neuropathy. This approach preserved the continuity of the attachment of the triceps with the ulnar nerve and allowed anterior subluxation of the ulnar nerve onto the hardware to be avoided. METHODS: From December 2018 to March 2020, 13 patients who underwent surgery for distal humerus fracture through the modified paratricipital approach at our hospital were prospectively enrolled in the study. Ulnar neuropathy, Mayo Elbow Performance Score (MEPS), and Range of motion (ROM) were evaluated. RESULTS: No postoperative ulnar neuropathy was observed. At the final follow-up, the mean Mayo Elbow Performance score was 97.7 (range, 85-100). The mean arc motion was 132.7° (range, 115°-145°) with a mean flexion contracture of 4.2° (range, 0°-10°) and mean flexion of 136.2° (range, 120°-145°). Hardware breakage leading to a loss of reduction occurred in one case, but the other fractures united. CONCLUSIONS: Our results demonstrated the effectiveness of the modified paratricipital approach for preventing postoperative ulnar neuropathy. The modified paratricipital approach is a safe and reliable method of performing distal humerus fracture surgery.

Perioperative Ulnar Neuropathy: A Contemporary Estimate of Incidence and Risk Factors.

BACKGROUND: Retrospective and prospective studies 2 decades ago from the authors' institution reported the incidence of perioperative ulnar neuropathy persisting for at least several months in a noncardiac adult surgical population to be between 30 and 40 per 100,000 cases. The aim of this project was to assess the incidence and explore risk factors for perioperative ulnar neuropathy in a recent cohort of patients from the same institution using a similar definition for ulnar neuropathy. METHODS: We performed a retrospective incidence and case-control study of all adults (≥18 years) undergoing noncardiac procedures with anesthesia services between 2011 and 2015. Each incident case of persistent ulnar neuropathy within 6 months of surgery was matched by age, sex, procedure date, and procedure type to 5 surgical patient controls. For the case-control study, separate conditional logistic regression analyses were performed to assess specific risk factors including the patient's body position and arm position, as well as body mass index (BMI), surgical duration, and selected patient comorbidities. RESULTS: Persistent ulnar neuropathy of at least 2 months duration was found in 22 of 324,124 anesthetics for patients who underwent these procedures during the study period for an incidence rate of 6.8 (95% confidence interval [CI], 4.3-10.3) per 100,000 anesthetics. The incidence of ulnar neuropathy was higher in men compared to women (10.7 vs 3.0 per 100,000; P = .016). From the matched case-control study, the odds of ulnar neuropathy increased with higher BMI (odds ratio [OR] = 1.67 [1.16-2.42] per 5 kg/m2 increase in BMI; P = .006), history of cancer (OR = 6.46 [1.64-25.49]; P = .008), longer procedures (OR = 1.53 [1.18-1.99] per hour; P = .001), and when 1 or both arms were tucked during surgery (OR = 6.16 [1.85-20.59]; P = .003). CONCLUSIONS: The incidence of persistent perioperative ulnar neuropathy observed in this study was lower than the incidence reported 2 decades ago from the same institution and using a similar definition for ulnar neuropathy. Several of the previously reported risk factors continue to be associated with the development of persistent perioperative ulnar neuropathy, providing ongoing targets for practice changes that might further decrease the incidence of this problem.

Sliding the Medial Pin: A Safer Approach to Cross-pinning Humerus Supracondylar Fractures?

INTRODUCTION: Many methods have been described to minimize the risk of ulnar nerve injury during the insertion of a medial pin for the percutaneous pinning of pediatric supracondylar humerus fractures (SCHF). The most recent AAOS Clinical Practice Guidelines suggests that physicians might want to avoid the use of medial-entry pins due to considerations of potential injury to the ulnar nerve. However, there are circumstances whereby a cross pin configuration is required. These include cases where there is medial wall comminution or due to the obliquity of the fracture. In this study, we present a group of patients with SCHF in which the medial pin was inserted using a new technique. MATERIALS AND METHODS: This is a retrospective case series approved by the local centralized institutional review board. The medical records of all patients who underwent closed reduction and percutaneous pinning for SCHF using a new technique-the sliding method-by a single pediatric orthopedic surgeon from August 2017 till January 2018 were reviewed. Patient demographics, fracture type, operative time, postoperative Baumann's angle, postoperative lateral capitellohumeral angle, and the rate of ulnar nerve palsy were recorded. RESULTS: This new technique was used in a total of 35 patients. Two patients were excluded as one had multiple same limb injuries, while another had a Gustilo 3A humerus supracondylar fracture. The average patient age at the time of surgery was 6.2 years (range: 2 to 12 y). There were 22 children with Gartland grade 3 fractures, 10 with grade 2b fractures, and 1 had a flexion type fracture. The average operative time was 21 minutes (range: 7 to 58 min). The average postoperative Baumann's angle was 73.9 degrees (range: 63.8 to 79.6 degrees) and the average postoperative lateral capitellohumeral angle was 44.6 degrees (range: 31.1 to 56.8 degrees). There were no cases of ulnar nerve palsy. CONCLUSIONS: The sliding method is a novel technique of protecting the ulnar nerve during closed reduction percutaneous pinning of SCHF. LEVEL OF EVIDENCE: Level IV.

Ulnar Nerve Management with Distal Humerus Fracture Fixation: A Meta-Analysis.

Ulnar nerve dysfunction following distal humerus fractures is a well-recognized phenomenon. There is no consensus regarding optimal handling of the ulnar nerve during surgical management of these fractures between in situ management and transposition. Using an electronic database to identify retrospective studies involving surgical fixation of distal humerus fractures yielded 46 studies, 5 trials meeting the authors' inclusion criteria, totaling 362 patients. An overall incidence of 19.3% for ulnar neuropathy was identified. Of those patients undergoing in situ release, the incidence was 15.3%. Of those who underwent transposition, there was a 23.5% incidence of ulnar neuropathy.

Ulnar Neuropathy in Cyclists.

The form and function of the cyclist exposes the ulnar nerve to both traction and compressive forces at both the elbow and wrist. Prevention of ulnar neuropathy and treatment of early symptoms include bike fitting, avoidance of excessive or prolonged weight-bearing through the hands, and the use of padded gloves. For persisting or progressive symptoms, a thorough history and physical examination is essential to confirm the diagnosis and to rule out other sites of nerve compression. The majority of compression neuropathies in cyclists resolve after appropriate rest and conservative treatment; however, should symptoms persist, nerve decompression may be indicated.

Distal Humerus Fractures: Open Reduction Internal Fixation.

Distal humerus fractures are challenging injuries for the upper extremity surgeon. However, recent techniques in open reduction internal fixation have been powerful tools in getting positive outcomes. To get such results, the surgeon must be aware of how to properly use these techniques in their respective practices. The method of fixation depends on the fracture, taking the degree of comminution and the restoration of the columns and articular surface into account. This article helps surgeons understand the concepts behind open reduction internal fixation of the distal humerus and makes them aware of pitfalls that may lead to negative results.

Is routine ulnar nerve transposition necessary in open release of stiff elbows? Our experience and a literature review.

PURPOSE: Prophylactic release of the ulnar nerve to reduce the incidence of postoperative nerve symptoms in stiff elbows has been recommended. However, the necessity for routine anterior transposition remains unclear. In this study, we aim to gain an insight into the value of routine transposition in open release of stiff elbows. METHODS: We retrospectively reviewed 94 patients suffering from elbow stiffness with no pre-operative ulnar nerve symptoms. Simple decompression (with in situ decompression or epicondylectomy) and subcutaneous anterior transposition were chronologically performed in 53 and 37 patients, respectively. Another four patients were treated by a single lateral approach with no intervention of the ulnar nerve. Pre- and postoperative range of motion and incidence of ulnar nerve symptoms were recorded. The function of ulnar nerve was measured by Amadio rating scale. RESULTS: The incidence of ulnar nerve dysfuction was 18.9% (ten of 53) and 8.1% (three of 37) in the simple decompression and transposition groups, respectively. The mean Amadio scores were 7.62 and 8.22, respectively. All these data showed a statistically significant difference (P < 0.05). In the lateral approach group, 50 % (two of four) of patients developed nerve symptoms with a mean Amadio score of 6.50. CONCLUSIONS: The transposition group exhibited a superior nervous outcomes compared with the simple decompression group. No comparison was conducted between the transposition and lateral approach groups because of too few patients in the latter. According to related literature and our experience, we conclude that routine transposition is necessary to prevent postoperative nerve symptoms.

Distal humerus fractures in patients over 65: complications.

INTRODUCTION: Fractures of the distal humerus in patients over the age of 65 remain a therapeutic challenge. Treatment options include conservative treatment, internal fixation or total elbow arthroplasty. The complications of these different treatment options were evaluated in a multicentre study. MATERIALS AND METHODS: Four hundred and ninety-seven medical records were evaluated. A retrospective study was performed in 410 cases: 34 received conservative treatment, 289 internal fixation and 87 underwent total elbow arthroplasty. A prospective study was performed in 87 cases: 22 received conservative treatment, 53 internal fixation, and 12 underwent total elbow arthroplasty. Patients were evaluated after at least 6 months follow-up. RESULTS: The rate of complications was 30% in the retrospective study and 29% in the prospective study. The rate of complications in the conservative treatment group was 60%, and the main complication was essentially malunion. The rate of complications was 44% in the internal fixation group and included neuropathies, mechanical failure or wound dehiscence. Although complications only developed in 23% of total elbow arthroplasties, they were often more severe than those following other treatments. DISCUSSION: Complications develop in one out of three patients over 65 with distal humerus fractures. Three main types of complications were identified. Neuropathies especially of the ulnar nerve, especially during arthroplasty, must always be identified, the nerve requiring isolation and transposition. Bone complications, due principally to mechanical failure, were found following internal fixation. Despite technical progress, care must be taken not to favor excessive utilization of this treatment option in complex fractures on fragile bone. Although there were relatively fewer complications with total elbow arthroplasty they were more difficult to treat. Ossifications were frequent whatever the surgical option and can jeopardize the functional outcome.

Ulnar neuropathy following distal humerus fracture fixation.

Ulnar nerve dysfunction is a well-recognized phenomenon following distal humerus fractures. Its fixed anatomic position predisposes the nerve to injury. Injury can occur at the time of injury, during closed-fracture manipulation, intraoperatively during fracture fixation (when it is routinely identified), or during fracture healing. Intraoperative management varies widely and can include in situ decompression or anterior transposition. This article reviews the literature and presents 24 patient cases. A 38% incidence of late ulnar neuropathy following open reduction and internal fixation is identified. There is no statistical difference between an in situ release and all anterior transpositions, except for submuscular.

Treatment of displaced pediatric supracondylar humerus fracture patterns requiring medial fixation: a reliable and safer cross-pinning technique.

INTRODUCTION: Treatment of displaced Gartland type 3 supracondylar humerus fractures in children may include closed reduction and percutaneous pinning. The pin configuration may be all-lateral entry or cross-pin. Despite the improved stability possible with cross-pinning, there is an inherent iatrogenic risk to the ulnar nerve of about 6%. As medial fixation may be necessary for certain fracture patterns, this study was conducted to evaluate the risk of ulnar neuropathy using a technique here described and developed to minimize injury to this structure. METHODS: A retrospective review was performed on all children treated for a supracondylar humerus fracture at our institution between 2003 and 2010. All the type 3 displaced fractures were placed into 2 groups: lateral-entry pinning and cross-pinning. The 2 groups were then compared for risk of ulnar nerve injury, and a post hoc power analysis was performed. RESULTS: A total of 381 supracondylar humerus fractures met the inclusion criteria. Our cross-pinning technique was used in 187 (49%) of the children with a mean age of 5.8 years (range, 0.92 to 13.92 y). There were 4 ulnar nerve injuries in the entire cohort and 2 sustained as iatrogenic injuries in the cross-pinning group (1.1%). There was no significant difference between our 2 groups in regard to risk of ulnar nerve injury (P=0.24). There is a statistically significant lower risk of ulnar nerve injury in our cross-pinning technique than previously described techniques (P=0.0028), with a post hoc power analysis of 93%. CONCLUSIONS: Despite the inherent risk for iatrogenic nerve injury with cross-pinning completely displaced supracondylar humerus fractures, there is often a need to use this technique to improve fixation and stability of the fracture. Our method of cross-pinning is safe and reproducible for providing fracture stability with a significant decrease in the risk of iatrogenic ulnar nerve injury (1 in 94) when a medial pin is required. LEVEL OF EVIDENCE: Level III-therapeutic studies.

The triceps-flexor carpi ulnaris (TRIFCU) approach to the elbow.

INTRODUCTION: Intra-articular fractures of the distal humerus frequently require internal fixation. Several approaches have been described, with the posterior approaches being most common. We present a new approach to the distal humerus via the lateral border of the triceps muscle. PATIENTS AND METHODS: The senior author has used this technique for fixation of intra-articular fractures of the distal humerus in 12 patients. RESULTS: The approach is equally useful for intra- and extra-articular fractures. No cases of postoperative ulna nerve neuropraxia have been encountered. There have been no postoperative wound complications. The exposure has allowed sufficient access to allow anatomically contoured plates to be easily applied to both sides of the distal humerus with confirmation of intra-articular fracture reduction. CONCLUSIONS: The approach has the advantages of leaving the muscular bed of the ulna nerve undisturbed, whilst still providing excellent exposure of the distal humerus. The triceps mechanism is not divided or split allowing rapid recovery of extensor function. Additionally, because of the natural carrying angle of the elbow, repositioning of the reflected triceps aponeurosis is easy.

Upper-limb somatosensory evoked potential monitoring in lumbosacral spine surgery: a prognostic marker for position-related ulnar nerve injury.

BACKGROUND CONTEXT: Somatosensory evoked potential (SSEP) is used to monitor integrity of the brain, spinal cord, and nerve roots during spinal surgery. It records the electrical potentials from the scalp after electrical stimulation of the peripheral nerves of the upper or lower limbs. The standard monitoring modality in lumbosacral spine surgery includes lower-limb SSEP and electromyography (EMG). Upper-limb SSEP monitoring has also been used to detect and prevent brachial plexopathy and peripheral nerve injury in thoracic and lumbosacral spine surgeries. We routinely monitor lower-limb SSEP and EMG in lumbosacral spine procedures at our institution. However, a few patients experienced postoperative numbness and/or pain in their ulnar distribution with uneventful lower-limb SSEP and EMG. PURPOSE: We hypothesized that the postoperative upper extremity paresis in lumbosacral surgeries may result from compression and/or stretch of the brachial plexus and/or ulnar nerve while the patients were in prone position. Using upper-limb SSEP, we investigated whether we observe any significant change in the SSEP, and if so, whether we can prevent or reduce frequency of postoperative upper extremity deficits. STUDY DESIGN/SETTING: In this prospective study, we monitored upper-limb SSEP, in addition to lower-limb SSEP and EMG, in 230 elective, posterior lumbosacral spinal procedures. All operations were performed by a group of four neurosurgeons. PATIENT SAMPLE: One hundred and thirty-one female and 99 male with an age range of 28 to 86 years between January 2004 and December 2005 were studied. OUTCOME MEASURES: Amplitude and latency of upper-limb or ulnar SSEP were continuously compared with those of the baseline. A greater than or equal to 50% decrease in SSEPs amplitude and/or a greater than or equal to 10% increase in latency were considered to be significant. METHODS: After intubation, patients were positioned prone on Jackson or Andrews spinal table. Anesthesia was maintained with inhalant gas (desflurane or sevoflurane) and propofol infusion with and without minimal infusion of narcotics (fentanyl, sufentanyl, or remifentanil). Intraoperative neurophysiologic monitoring of upper-limb or ulnar SSEP was achieved by continuously recording cortical and subcortical responses after alternate stimulation of the ulnar nerve at the wrist. In our institutional protocol, a greater than or equal to 50% decrease in SSEPs amplitude and/or a greater than or equal to 10% increase in latency were considered to be significant to alert the operating surgeons. When significant changes occurred, the surgeon was immediately notified. Also, reevaluation of vital signs, depth of anesthesia, and patient's position, and technical troubleshootings were subsequently followed. RESULTS: We observed a greater than or equal to 50% decrease in amplitude of ulnar SSEP in 10 patients without significant changes in lower-limb SSEP (peroneal or posterior tibial nerve SSEP) or EMG during surgery. Eight patients had changes in unilateral limbs, and two patients had changes in bilateral limbs. Two patients with significant changes in unilateral limbs showed changes twice. The mean SSEP amplitude for the 14 changes was 29.2+/-3.1% (mean+/-SEM, standard error of mean) of the baseline value at the average surgical time of 60+/-1.5 minutes. With repositioning of the arms, the amplitudes were immediately restored with the average of 70.2+/-7.1% (n=14) of the baseline value. The mean amplitude of upper-limb SSEP was 73.4+/-8.7% (n=12) of the baseline at wound closure. The average surgical time was 154+/-29.2 minutes per case for the 10 patients. There was no documented postoperative upper extremity paresis in all 230 patients. CONCLUSIONS: The present study demonstrates that upper-limb SSEP monitoring could detect position-related ulnar neuropathy in 5.2% of the patients undergoing lumbosacral spine surgery.

[Positioning of the patient for surgery]. / Lagerung des Patienten zur Operation.

The success of an operation does not only depend on a perfect surgical technique, an appropriate anesthesia, convenient surgical instruments and functional technical equipment, but also on a proper operative positioning. Meeting the requirements of the surgeon, the positioning has also to be in accordance with the patient's individual needs. Seemingly trivial in "simple" positions, there must be paid attention to details, as they can have serious harm to the patient if done incorrectly. The surgeon is in charge for the positioning, but the performance is done in a horizontal division of work between surgeon and anesthesiologist. This article describes standard positions, demonstrates their realization and special damages, and points out juristic aspects as well as technical items like operating table and positioning facilities.

Ensaio clínico e neurofisiológico sobre a resposta do nervo ulnar, na hanseníase em reação tipo 1 e tipo 2, sob diferentes regimes de esteróides via oral

A neuropatia da hanseníase se agrava durante as reações e evolui, freqüentemente, com perda axonal, para as deficiências físicas. Do conhecimento dos mecanismos fisiopatológicos e do seu tratamento adequado dependem as ações de prevenção das incapacidades. Portanto,interessa avaliar os diferentes regimes de esteróides via oral e, secundariamente, caracterizar o comportamento neurofisiológico dos nervos nas reações tipo 1 e tipo 2. O experimento foi um ensaio clínico e neurofisiológico aleatório, com duração de seis meses, tendo como modelo o nervo ulnar em pacientes de hanseníase, em reação tipo 1 (RT1) e reação tipo 2 (RT2) referenciado para o Instituto Lauro de Souza Lima. Dentre 188 pacientes atendidos no período da pesquisa foram selecionados 21 pacientes, 12 com RT1 e nove com RT2 (42 nervos). Oito nervos não apresentavam comprometimento neurológico, totalizando-se 34 nervos com neuropatia. Os regimes de esteróides com doses iniciais mais elevadas produziram diferenças com significância estatística até o primeiro mês, tanto nos nervos com RT1 como RT2. Quando comparados os resultados finais, período onde as doses se assemelharam, não houve diferenças significativas. Quando o tratamento foi instituído com menos de três meses do início dos sintomas não foram encontradas diferenças efetivas nos resultados entre os regimes de esteróides. As alterações neurofisiológicas desmielinizantes e axonais ocorreram ao longo de todo o nervo, sendo exuberante através do cotovelo tanto nos nervos com RT1 como nos nervos como RT2. A desmielinização predominou na RT1 comparada a RT2, assim como a remielinização sob o tratamento, tanto aguda como tardiamente. As respostas aos esteróides foram dose-dependentes em ambas as reações. Entretanto, quando instituído o tratamento precocemente as respostas aos diferentes regimes de esteróides se equivaleram. Foi evidenciado o predomínio do envolvimento mielínico nas RT1 comparadas às RT2.

Ensaio clínico e neurofisiológico sobre a resposta do nervo ulnar, na hanseníase em reação tipo 1 e tipo 2, sob diferentes regimes de esteróides via oral / Clinical and neurophysiologic radomized trial about ulnar neruropathy responses, in type 1 and type 2 hansen's disease reactions under oral steroid treatment

A neuropatia da hanseníase se agrava durante as reações e evolui, freqüentemente, com perda axonal, para as deficiências físicas. Do conhecimento dos mecanismos fisiopatológicos e do seu tratamento adequado dependem as ações de prevenção das incapacidades. Portanto,interessa avaliar os diferentes regimes de esteróides via oral e, secundariamente, caracterizar o comportamento neurofisiológico dos nervos nas reações tipo 1 e tipo 2. O experimento foi um ensaio clínico e neurofisiológico aleatório, com duração de seis meses, tendo como modelo o nervo ulnar em pacientes de hanseníase, em reação tipo 1 (RT1) e reação tipo 2 (RT2) referenciado para o Instituto Lauro de Souza Lima. Dentre 188 pacientes atendidos no período da pesquisa foram selecionados 21 pacientes, 12 com RT1 e nove com RT2 (42 nervos). Oito nervos não apresentavam comprometimento neurológico, totalizando-se 34 nervos com neuropatia. Os regimes de esteróides com doses iniciais mais elevadas produziram diferenças com significância estatística até o primeiro mês, tanto nos nervos com RT1 como RT2. Quando comparados os resultados finais, período onde as doses se assemelharam, não houve diferenças significativas. Quando o tratamento foi instituído com menos de três meses do início dos sintomas não foram encontradas diferenças efetivas nos resultados entre os regimes de esteróides. As alterações neurofisiológicas desmielinizantes e axonais ocorreram ao longo de todo o nervo, sendo exuberante através do cotovelo tanto nos nervos com RT1 como nos nervos como RT2. A desmielinização predominou na RT1 comparada a RT2, assim como a remielinização sob o tratamento, tanto aguda como tardiamente. As respostas aos esteróides foram dose-dependentes em ambas as reações. Entretanto, quando instituído o tratamento precocemente as respostas aos diferentes regimes de esteróides se equivaleram. Foi evidenciado o predomínio do envolvimento mielínico nas RT1 comparadas às RT2.

A reservable antiadhesion barrier gel reduces the perineural adhesions in rats after anastomosis.

AIM: The objective of this experimental study was to assess the effectiveness of ADCON T/N in reducing perinerural adhesions when applied around a previously exposed and then anastomosed peripheral nerve in a rat model. METHODS: Sixteen adult 8-month-old male Wistar rats were used for this study. After the ulnar nerve was exposed bilaterally, the nerves were sectioned and anastomosised. ADCON T/N gel was applied around the nerve suture on 1 limb, while the contralateral limb was left untreated (sham operated control). Treatments were administered according to a randomised schedule revealed to the operator only after the perineural adhesions observed during the 2nd operation had been dissected and complete haemostasis achieved. In other group of 4 Wistar rats, the ulnar nerve was sectioned and the 2 ends connected with a 5 mm silastic tube that was placed bilaterally in each rat but on only one side, chosen randomly, was the nerve treated with ADCON TN and placed within the tube on that side. RESULTS: Three months after the 1st operation, the same nerves were exposed again in all animals under general anesthesia before microsurgical external neurolysis. The neurolysis sites in 16 rats were evaluated by blinded surgical dissection immediately before death. Parameters examined included: quality of wound healing, possible adverse effects, presence of residual implant material and perineural adhesions. Perineural adhesions around the ulnar nerve were visually scored using a 4-point qualitative scale (Mean 2.81 without gel, and 1.18 with ADCON T/N. p=0.017). There was no evidence of persistence of residual implant material in the ADCON T/N treated sites. No significant difference between the average density of myelinated axons was observed in either group. All ADCON T/N treated rats (4 animals) showed axonal growth through the tube connecting the 2 ends. CONCLUSION: ADCON-TN decreased fibrosis around the nerve anastomosis sites and did not impede growth between the severed ends of the axons. If reoperation becomes necessary, a reduction of fibrosis would facilitate access to the old site and decrease the risk of nerve lesions.

Predicting ulnar nerve location in pinning of supracondylar humerus fractures.

Thirty-four consecutive patients with displaced supracondylar humerus fractures were treated with reduction and percutaneous pinning. The precise location of the ulnar nerve to the medial pin was determined by intraoperative nerve stimulation. In 22 of the 34 patients, the authors attempted to predict the location of the ulnar nerve by palpation and placing a mark on the skin. They also recorded the ability to feel the anatomic landmarks for pin fixation, including the medial epicondyle and ulnar nerve. The average distance from the medial pin to the predicted location was 9.3 mm, whereas the actual distance measured 7.6 mm, for a significant difference of 1.7 mm. Statistically, the authors could not accurately predict the location of the ulnar nerve prior to blind percutaneous crossed K-wire fixation of supracondylar humerus fractures. However, clinically they were fairly close in their prediction and documented safe insertion and distance from the nerve. Intraoperative nerve stimulation may assist in localizing the nerve prior to placement of the medial pin. Stimulation of the pin itself following insertion is another technique to ensure safe pin placement and decrease the risk of injury.