Fibular Head Research Articles

Acute Effects of Selective Strength Exercise on the Peroneus Longus and Brevis

The peroneus muscles are muscles that mainly act in ankle eversion and can be divided into PL and PB, which have different but important roles in foot and ankle functions. Therefore, PL and PB dysfunction can lead to foot and ankle issues, making. selective strength exercise necessary. This study aimed to identify the effect of two different exercise techniques on PL and PB morphologies. Two interventions were performed on separate days: the PL intervention, in which a Thera-Band® was placed on the ball of the foot and pushed out from the contact point, and the PB intervention, in which the Thera-Band® was pulled from the base of the fifth metatarsal. Cross-sectional area (CSA) and thickness of the peroneus muscles at 25% (showing the PL morphology) and 75% (showing the PB morphology) proximal to the line connecting the fibular head and lateral malleolus, as well as ankle strength was measured before and immediately after the interventions and at 10, 20, and 30 min later. A repeated-measures two-way analysis of variance was conducted to identify differences in the effects of the interventions on the PL and PB. Main and interaction effects on CSA, thickness, and ankle strength, with a significant increase in CSA and thickness in the proximal 25% in the PL intervention and the distal 75% in the PB intervention immediately after implementation, were observed (p < 0.05). The transient increase in muscle volume due to edema immediately after exercise indicates the acute effect of exercise. The CSA and thickness of the proximal 25% in the PL intervention and the distal 75% in the PB intervention increased immediately after the intervention, indicating that these interventions can be used to selectively exercise the PL and PB.

Relationship between the Young's Modulus of the Achilles Tendon and Ankle Dorsiflexion Angle at Maximum Squat Depth in Healthy Young Males.

Background and Objective: Achilles tendon (AT) stiffness can reduce ankle dorsiflexion. However, whether AT stiffness affects the ankle dorsiflexion angle at a maximum squat depth remains unclear. Therefore, we aimed to investigate the relationship between the Young's modulus of the AT and ankle dorsiflexion angle at the maximum squat depth in healthy young males using shear-wave elastography (SWE). Materials and Methods: This cross-sectional study included 31 healthy young males. AT stiffness was measured using the Young's modulus through SWE. The ankle dorsiflexion angle at the maximum squat depth was measured as the angle between the vertical line to the floor and the line connecting the fibula head and the lateral malleolus using a goniometer. Results: Multiple regression analysis identified the Young's modulus of the AT at 10° of ankle dorsiflexion (standardized partial regression coefficient [β] = -0.461; p = 0.007) and the ankle dorsiflexion angle in the flexed knee (β = 0.340; p = 0.041) as independent variables for the ankle dorsiflexion angle at maximum squat depth. Conclusions: The Young's modulus of the AT may affect the ankle dorsiflexion angle at the maximum squat depth in healthy young males. Therefore, improving the Young's modulus of the AT may help increase the ankle dorsiflexion angle at maximum squat depth.

An AI-Based Image Quality Control Framework for Knee Radiographs

Image quality control (QC) is crucial for the accurate diagnosis of knee diseases using radiographs. However, the manual QC process is subjective, labor intensive, and time-consuming. In this study, we aimed to develop an artificial intelligence (AI) model to automate the QC procedure typically performed by clinicians. We proposed an AI-based fully automatic QC model for knee radiographs using high-resolution net (HR-Net) to identify predefined key points in images. We then performed geometric calculations to transform the identified key points into three QC criteria, namely, anteroposterior (AP)/lateral (LAT) overlap ratios and LAT flexion angle. The proposed model was trained and validated using 2212 knee plain radiographs from 1208 patients and an additional 1572 knee radiographs from 753 patients collected from six external centers for further external validation. For the internal validation cohort, the proposed AI model and clinicians showed high intraclass consistency coefficients (ICCs) for AP/LAT fibular head overlap and LAT knee flexion angle of 0.952, 0.895, and 0.993, respectively. For the external validation cohort, the ICCs were also high, with values of 0.934, 0.856, and 0.991, respectively. There were no significant differences between the AI model and clinicians in any of the three QC criteria, and the AI model required significantly less measurement time than clinicians. The experimental results demonstrated that the AI model performed comparably to clinicians and required less time. Therefore, the proposed AI-based model has great potential as a convenient tool for clinical practice by automating the QC procedure for knee radiographs.

Transtibial Amputation with Fibulectomy and Fibular Collateral Ligament-Biceps Reconstruction: Surgical Technique and Clinical Experience.

To describe our clinical experience and surgical technique of transtibial amputation with fibulectomy and fibular collateral ligament-biceps reconstruction for management of, particularly short, transtibial amputations with proximal fibula prominence, overt instability, or inadequate soft tissue coverage. Retrospective review. Level II trauma center. Twelve consecutive patients who underwent transtibial amputation with fibulectomy and fibular collateral ligament-biceps reconstruction between 2008-2021. We reviewed patient medical records, radiographs, and clinical photographs. Complications, instability, pain. Eight patients underwent acute transtibial amputation with fibulectomy and reconstruction, whereas four patients underwent amputation revision with fibulectomy and reconstruction for chronic pain. All 12 patients were male, with a median age of 39 years [interquartile range (IQR), 33-46]. All injuries were due to high-energy mechanisms, including improvised explosive device (n=8), rocket propelled grenade (n=2), gunshot wound (n=1), and motor vehicle accident (n=1). After a median follow-up of 8.5 years (IQR, 3.4-9.3), there was one complication, a postoperative suture abscess. No patients had subjective lateral knee instability following the procedure and average pain scores decreased from 4.75 to 1.54 (p=0.01). All patients returned to regular prosthesis wear and maintained independent functioning with activities of daily living. Our experience with fibulectomy and fibular collateral ligament-biceps reconstruction demonstrated no subjective or clinical postoperative instability and may be a useful adjunct for managing transtibial amputations with fibular instability or prominence, pain, or skin breakdown at the fibular head. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Sural communicating nerve for application as a vascularized nerve graft: A microneurovascular anatomic study in cadavers.

Sural nerve harvest causes paraesthesia to the lateral heel of the foot, which can debilitate those with already compromised proprioception. To circumvent this, we investigated an alternative donor nerve, branch of the lateral sural nerve complex called the sural communicating nerve (SCoNe), for its harvest and use as a vascularized nerve graft, in cadaver. The SCoNe was visualized by dissection in 15 legs from 8 human cadavers and the relationship of the SCoNe to the overall sural nerve complex was documented. The surface markings, dimensions, and the micro-neurovascular anatomy in the super-microsurgery range (up to 0.30 mm) of the SCoNe was recorded and analyzed. SCoNe graft surface marking was confined within a triangle drawn between the fibular head laterally, the popliteal vertical midline medially and the tip of the lateral malleolus inferiorly. The proximal end of the SCoNe was situated at a mean intersection distance of 5 cm from both the fibular head and popliteal midline respectively. The mean length of the SCoNe was 226 ± 43 mm with a mean proximal diameter of 0.82 mm and mean distal diameter of 0.93 mm. In 53% of the cadavers, an arterial input was present in the proximal third of the SCoNe and veins were predominantly (87%) present in the distal third. In 46% and 20% of the 15 legs respectively, there was a nutrient artery and vein perfusing the SCoNe in its central segment. The external mean diameter of this artery was 0.60 ± 0.30 mm, while the vein was slightly larger with a mean diameter of 0.90 ± 0.50 mm. SCoNe graft may preserve lateral heel sensation, compared to sural nerve harvest, pending clinical studies. It may have wide applications as a vascularized nerve graft, including being ideal as a vascularized cross-facial nerve graft because its nerve diameter is similar to the distal facial nerve branches. The accompanying artery is a good anastomotic match to the superior labial artery.

Noxious radiant heat evokes bi-component nociceptive withdrawal reflexes in spinal cord injured humans-A clinical tool to study neuroplastic changes of spinal neural circuits.

Investigating nocifensive withdrawal reflexes as potential surrogate marker for the spinal excitation level may widen the understanding of maladaptive nociceptive processing after spinal cord injury (SCI). The aim of this prospective, explorative cross-sectional observational study was to investigate the response behavior of individuals with SCI to noxious radiant heat (laser) stimuli and to assess its relation to spasticity and neuropathic pain, two clinical consequences of spinal hyperexcitability/spinal disinhibition. Laser stimuli were applied at the sole and dorsum of the foot and below the fibula head. Corresponding reflexes were electromyography (EMG) recorded ipsilateral. Motor responses to laser stimuli were analyzed and related to clinical readouts (severity of injury/spasticity/pain), using established clinical assessment tools. Twenty-seven participants, 15 with SCI (age 18-63; 6.5 years post-injury; AIS-A through D) and 12 non-disabled controls, [non-disabled controls (NDC); age 19-63] were included. The percentage of individuals with SCI responding to stimuli (70-77%; p < 0.001), their response rates (16-21%; p < 0.05) and their reflex magnitude (p < 0.05) were significantly higher compared to NDC. SCI-related reflexes clustered in two time-windows, indicating involvement of both A-delta- and C-fibers. Spasticity was associated with facilitated reflexes in SCI (Kendall-tau-b p ≤ 0.05) and inversely associated with the occurrence/severity of neuropathic pain (Fisher's exact p < 0.05; Eta-coefficient p < 0.05). However, neuropathic pain was not related to reflex behavior. Altogether, we found a bi-component motor hyperresponsiveness of SCI to noxious heat, which correlated with spasticity, but not neuropathic pain. Laser-evoked withdrawal reflexes may become a suitable outcome parameter to explore maladaptive spinal circuitries in SCI and to assess the effect of targeted treatment strategies. Registration: https://drks.de/search/de/trial/DRKS00006779.

Anatomic Fibular Collateral Ligament and Anterior Cruciate Ligament Reconstruction With Concomitant Biceps Femoris Avulsion Repair

Background: Injuries to the fibular collateral ligament (FCL) seldom occur in isolation and may present with a concomitant injury to the biceps femoris tendon and anterior cruciate ligament (ACL). Injuries to structures of the posterolateral corner (PLC) lead to varus and rotational instability of the knee, subjecting the cruciate ligaments to increased forces that may result in graft failure. Therefore, reconstruction of these structures should be performed concurrently with the ACL. Indications: Grade III FCL injuries heal poorly without operative treatment and often result in residual varus instability of the knee that increases medial knee compartment forces, and forces on both the native ACL and the graft status post ACL reconstruction. Therefore, preservation of biomechanical stability and long-term health of the knee are reliant on addressing injuries to the PLC surgically. Technique Description: A key concept of this surgical technique is a meticulous peroneal nerve neurolysis in the setting of altered biceps femoris anatomy, and the proper order of the surgical steps for tunnel creation, graft passage, and fixation and suture anchor insertion to achieve optimal patient outcomes. The described technique involves a lateral surgical approach, peroneal neurolysis, and preparation of fibular and femoral FCL tunnels, followed by a Bone-patellar tendon-bone graft (BTB) graft harvest. Attention is then turned to intra-articular work including the diagnostic arthroscopy, femoral and tibial tunnel preparation, passage of the ACL graft, and fixation of the grafts in femoral tunnels. Last, fixation is achieved in the following order: FCL graft on fibula, ACL graft on tibia, and biceps femoris tendon to fibular head. Results: Compared with the preoperative state, Moulton et al reported significant improvements in the average Lysholm and Western Ontario scores at 2.7 years postoperatively following anatomic FCL reconstrution. Furthermore, Thompson et al reported on primary suture anchor repair of distal biceps femoris in 22 elite athletes and reported that all patients had returned to their preinjury level of sporting activity at 2-year follow-up. Discussion: Anatomic reconstructions of the FCL and ACL, such as the one described in our technique, effectively restore near native knee biomechanics and offer superior clinical outcomes compared with nonanatomic-based FCL reconstructions. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Quality of long standing radiographs assessment of the patella position

BackgroundThe gold standard for evaluating leg alignment is a long leg standing radiograph (LSR). The research states that a correct LSR should have a patella that is centered and facing forward as well as a fibula head superimposition (FHS) with a tibia that is 1/3 larger than the fibula. The purpose of this study was to determine levels of quality for LSR by quantifying and correlating the patella position and fibular head superimposition. Method741 lower limbs were included using two distinct measurement techniques, we calculated the patella position's (PD) departure from the center of the knee joint (M1 and M2). To measure the inter-rater dependability in assessing PD and FHS, intraclass correlation coefficients were determined. The Bland-Altman approach was used to compare M1 with M2’s performance. We created three quality groups based on the average quantity of PD. ResultsThe mean PD was 3.5 mm for M1 and 4.1 mm for M2, respectively. Three quality categories were created: group A for PD ≤ 5 mm, group B for PD 5–10 mm, and group C for PD of ≥10 mm. Group A takes up 70.9% of the LSR. Interestingly, group A's FHS was 21.3% than the typical value of 1/3. ConclusionsThe patella’s center should be centered within a 5 mm range and the fibular head should be 1/5 covered from the tibia. This study is the first to define quantitative metrics based on LSR analysis. Level of EvidenceLevel IV (diagnostic retrospective case series).

Author Response: Staged Reconstruction of Post-traumatic Medial Malleolus Bone Defects Using Fibular Head Osteochondral Graft: A Report of Two Cases

Author Response: Staged Reconstruction of Post-traumatic Medial Malleolus Bone Defects Using Fibular Head Osteochondral Graft: A Report of Two Cases

Letter to the Editor: Staged Reconstruction of Post-traumatic Medial Malleolus Bone Defects Using Fibular Head Osteochondral Graft: A Report of Two Cases

Letter to the Editor: Staged Reconstruction of Post-traumatic Medial Malleolus Bone Defects Using Fibular Head Osteochondral Graft: A Report of Two Cases

Single-Centre Experience Regarding the Use of Fibular Graft for Reconstruction after Resection of Grade III GCT of Distal Radius.

Background: A giant cell tumour (GCT) is a locally invasive benign tumour of bone in young adults. Treatment includes surgical resection as first-line or denosumab pharmacotherapy in inoperable patients. However, surgical resection of distal radius GCT has produced debatable functional outcomes. Here we study the use of fibular grafts for reconstruction of surgically resected GCT of the distal radius. Methods: A total of 11 patients having Grade III GCT of the distal radius were recruited for a retrospective single-centred study. Five underwent arthrodesis with fibular shaft graft and six received arthroplasty with the proximal fibula. Functional outcomes at 6 weeks, 6 and 12 months were measured by Mayo wrist score (MWS) (>51% = good) and Revised Musculoskeletal tumor society (MSTS) score (>15 = good). Results: At 6 weeks, mean MSTS score and MWS were 23.64 and 58.64% respectively, and the length of the fibular graft was a predictor for both MSTS score (p = 0.014) and MWS (p = 0.006). At 6 months, the mean MSTS and MWS were 26.36 and 76.82%, respectively. At 6 months, the surgical procedure was a predictor in MSTS score (p = 0.02) while MWS was predicted by length of graft (p = 0.02). At 12 months, MSTS score was 28.73, and MWS remained 91.82%. Length of the fibular graft was an insignificant predictor, but a significant risk factor was surgical procedure for MWS (p = 0.04) at 12 months. No variable was found significant for MSTS score. Conclusions: Resection along with reconstruction of Grade III GCT of the radius with fibular graft was found an optimal treatment option. Also, use of the fibular head grafts and shorter length grafts are predictors for better outcomes after surgery. Level of Evidence: Level IV (Therapeutic).

Identification of the joint line in revision total knee arthroplasty using a multiple linear regression model: a cadaveric study.

The results of revision total knee arthroplasty (rTKA) may be compromised by excessive joint line (JL) elevation. It is critical but challenging in reestablishing the JL in rTKA. Previous studies have confirmed that, biomechanically and clinically, JL elevation should not exceed 4mm. Image-based studies described several approaches to locate the JL intraoperatively, however magnification errors could occur. In this cadaveric study, we aim to define an accurate and reliable method to determine the JL. Thirteen male and eleven female cadavers were used, with an average age of death being 48.3years. The transepicondylar width (TEW), the distance from the medial (MEJL) and lateral (LEJL) epicondyle, adductor tubercle (ATJL), fibular head (FHJL) and tibial tubercle (TTJL) to the JL were measured in 48 knees. Intra- and interobserver reliability and validity were tested prior to any additional analysis. Pearson correlation and linear regression analysis were used to examine the correlations between landmark-JL distances (LEJL, MEJL, ATJL, FHJL and TTJL) and the TEW, and to further derive models for intraoperative JL determination. The accuracy of different models, quantified by errors between estimated and measured landmark-JL distances, was compared using the Friedman and post hoc Dunn tests. The intra- and inter-observer measurements for TEW, MEJL, LEJL, ATJL, TTJL and FHJL did not differ significantly (p > 0.05). Between genders, significant differences were found on TEW, MEJL, LEJL, ATJL, FHJL and TTJL (p < 0.05). There was no association between TEW and either FHJL or TTJL (p > 0.05), while ATJL, MEJL, and LEJL were found to be correlated with TEW (p < 0.05). Six models were derived: (1) MEJL = 0.37*TEW (r = 0.384), (2) LEJL = 0.28*TEW (r = 0.380), (3) ATJL = 0.47*TEW (r = 0.608), (4) MEJL = 0.413*TEW-4.197 (R2 = 0.473), (5) LEJL = 0.236*TEW + 3.373 (R2 = 0.326), (6) ATJL = 0.455*TEW + 1.440 (R2 = 0.556). Errors were defined as deviations between estimated and actual landmark-JL distances. The mean absolute value of the errors, created by Model 1-6 was 3.18 ± 2.25, 2.53 ± 2.15, 2.64 ± 2.2, 1.85 ± 1.61, 1.60 ± 1.59 and 1.71 ± 1.5, respectively. The error could be limited to 4mm in 72.9%, 83.3%, 72.9%, 87.5%, 87.5%, and 93.8% of the cases by referencing Model 1-6, respectively. Compared to previous image-based measurements, the current cadaveric study most closely resembles a realistic view of intraoperative settings and could circumvents magnification errors. We recommend using Model 6, the JL can be best estimated by referencing the AT and the ATJL can be calculated as ATJL (mm) = 0.455*TEW (mm) + 1.440 (mm).

Surgical treatment of proximal humerus fractures with using the original allogeneic fibula graft: retrospective cohort study

BACKGROUND: A proximal humerus fracture (PHF) is quite common and accounts for approximately 5% of all fractures. During surgery, these fractures make it difficult to correctly reattach the bone fragments. Various special techniques are needed for repositioning and stable fixation of the fragments. When considering the most effective ways to facilitate fracture repositioning and prevent secondary displacement, we paid attention to the publications on the use of the fibula graft.&#x0D; AIM: To evaluate the effectiveness of a new allogeneic bone-collagen graft from the fibula head in PHF osteosynthesis with a plate having angular stability in conditions of bone tissue deficit.&#x0D; MATERIALS AND METHODS: An original bone-collagen allogeneic graft from the proximal part of the fibula was developed. We carried out a comparative analysis of the treatment results in patients operated on using the fibula head allograft (group O 48 patients, subgroup O1 - 35 patients; period - not less than 1 year after surgery) and the group without using augmentation graft (group K 32 patients). The results were assessed using clinical, radiological, and standardized Constant Shoulder Score; the statistical analysis was also performed.&#x0D; RESULTS: No patient in group O developed secondary dislocation, while in group K it was noted in 5 (16%) patients. Head collapse developed in 3 patients (7%) in group O and 8 (25%) in group K. Surgery time was shorter in group O than in group K. The mean Constant Scholder Score in subgroup O1 was 78 and in group K 70. Thinning in the cortical layer of the graft and the border disappearance between the spongy part of the graft and the bone tissue of the humeral head were noted in all patients during multispiral CT scanning over time, which was considered a sign of graft remodeling and lysis.&#x0D; CONCLUSION: In severe PHF with bone deficit, it is possible to perform organ preseration surgery regardless of the patients age and obtain functional results satisfying both the patient and the physician. Our suggested method of severe PHF surgical treatment combined with bone deficit facilitates repositioning, reduces operation time, and decreases the number of complications.

A Young Skier with Leg Pain

BackgroundProximal tibiofibular joint (PTFJ) dislocation is a rare injury that can disrupt the proximal tibia-fibula joint. The abnormalities in knee x-ray imaging can be subtle and difficult to detect, requiring careful assessment. This rare cause of lateral knee pain requires a high level of suspicion for diagnosis. Treatment is closed reduction; unstable PTFJ dislocations often require surgical intervention. Case ReportA 17-year-old young man presented to the emergency department (ED) with right lateral knee pain and difficulty walking after colliding with another skier 2 days prior. The examination showed right lateral ecchymosis and tenderness over the lateral proximal fibula. He remained neurovascularly intact with a full passive and active range of motion. X-ray studies were obtained. The patient was referred by his outpatient orthopedic surgeon after the initial knee x-ray study was concerning for PTFJ dislocation and unsuccessful reduction. In the ED, the patient underwent moderate sedation and successful orthopedic-guided reduction via medial force on the lateral fibular head, while hyper-flexing the knee and holding the foot dorsiflexed and everted. Post-reduction radiographs showed improved proximal tibiofibular alignment without fracture. Why Should an Emergency Physician Be Aware of This?PTFJ dislocation is a rare injury that can be missed easily and requires a high level of suspicion when presented with an acute traumatic knee pain. Closed reduction of PTFJ dislocation can be achieved in the ED and early identification can prevent long-term sequelae.

Novel ideas for the comprehensive evaluation of varus knee osteoarthritis: radiological measurements of the morphology of the lateral knee joint

BackgroundThe lateral anatomical and morphological characteristics of knees with varus knee osteoarthritis (OA) have not received sufficient attention. This study used several radiological parameters to describe the morphological characteristics of the lateral knee with OA to determine whether there are relationships between varus knee OA and parameters such as lateral plateau widening (LPW), proximal fibula curvature (PFC), and fibula height (FH).MethodsThe study retrospectively analyzed 1072 subjects who underwent standard radiography for diagnosing or evaluating symptomatic knee joint disease. The 163 Kellgren and Lawrence (K–L) grades 0 and I knees were categorized into the no-knee-OA group, and the 909 K–L grades II–IV knees were classified into the knee-OA group. Medial proximal tibial angle, joint line convergence angle, hip–knee–ankle angle, LPW, PFC, and FH were measured. T tests and chi-square tests were used to compare each index between the two groups. Binary logistic regression was performed to examine the correlation between indexes and knee OA occurrence. Ordinal logistic analysis, principal component analysis, and multivariable linear regression analysis were performed to examine the correlations between the three lateral parameters and K–L grades and the degree of varus deformity.ResultsLPW and PFC were significantly greater and FH was significantly smaller in the knee-OA group than in the no-knee-OA group. LPW, PFC, and FH were correlated with knee OA occurrence. One principal component, named the comprehensive principal component score of varus deformity, was extracted from the three indexes, and the total variance of the principal component interpretation was 76.60%. Ordinal logistics and multivariable linear regression analysis showed that, after adjusting for age and BMI, LPW and PFC were positively correlated with K–L grading and varus deformity. FH was significantly and negatively correlated with K–L grading and varus deformity (all P < 0.05).ConclusionsRegular morphological changes take place in the lateral knee with varus OA, including lateral dislocation of the tibial plateau, proximal fibula bending, and upward movement of the fibular head. Changes in LPW, PFC, and FH could enable a more comprehensive assessment of varus knee OA occurrence, severity, and deformity.Level of evidence Retrospective Study Level III.

Proximal Tibiofibular Joint Instability: An Underrecognized Cause of Lateral Knee Pain and Mechanical Symptoms.

Instability of the proximal tibiofibular joint is an uncommon and often unrecognized cause of lateral knee pain, mechanical symptoms, and instability. The condition results from one of three etiologies: acute traumatic dislocation, chronic or recurrent dislocations, and atraumatic subluxations. Generalized ligamentous laxity is a key predisposing factor for atraumatic subluxation. Instability of this joint may be in the anterolateral, posteromedial, or superior directions. Anterolateral instability is the most common type (80% to 85%) frequently occurring with hyperflexion of the knee with the ankle plantarflexed and inverted. Patients with chronic instability report lateral knee pain with snapping or catching often leading to a misdiagnosis of lateral meniscal pathology. Subluxations may be treated conservatively with activity modification, supportive straps, and knee-strengthening physical therapy. Chronic pain or instability is an indication for surgical treatment including arthrodesis, fibular head resection, or soft-tissue ligamentous reconstruction. Newly developed implants and soft-tissue graft reconstruction techniques provide secure fixation and stability with less invasive procedures and without the need for arthrodesis.

Management Of Spastic Equinovarus Foot in Children with Cerebral Palsy: An Evaluation of Anatomical Landmarks for Selective Nerve Blocks of the Tibial Nerve Motor Branches

To define the anatomical landmarks of tibial motor nerve branches for selective motor nerve blocks of the gastrocnemii, soleus and tibialis posterior muscles in the management of spastic equinovarus foot. Observational study. Twenty-four children with cerebral palsy with spastic equinovarus foot. Considering the affected leg length, motor nerve branches to the gastrocnemii, soleus and tibialis posterior muscles were tracked using ultrasonography, and located in the space (vertical, horizontal, deep) according to the position of fibular head (proximal/distal) and a virtual line from the middle of popliteal fossa to the Achilles tendon insertion (medial/lateral). Location of motor branches was defined as percentage of the affected leg length. Mean coordinates were: for the gastrocnemius medialis 2.5 ± 1.2% vertical (proximal), 1.0 ± 0.7% horizontal (medial), 1.5 ± 0.4% deep; for the gastrocnemius lateralis 2.3 ± 1.4% vertical (proximal), 1.1 ± 0.9% horizontal (lateral), 1.6 ± 0.4% deep; for the soleus 2.1 ± 0.9% vertical (distal), 0.9 ± 0.7% horizontal (lateral), 2.2 ± 0.6% deep; for the tibialis posterior 2.6 ± 1.2% vertical (distal), 1.3 ± 1.1% horizontal (lateral), 3.0 ± 0.7% deep. These findings may help the identification of tibial motor nerve branches to perform selective nerve blocks in patients with cerebral palsy with spastic equinovarus foot.

Anatomical and Biomechanical Characteristics of the Anterolateral Ligament: A Descriptive Korean Cadaveric Study Using a Triaxial Accelerometer.

Background and Objectives: The anterolateral ligament (ALL) could be the potential anatomical structure responsible for rotational instability after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to investigate the anatomical and biomechanical characteristics of the ALL in Korean cadaveric knee joints. Materials and Methods: Twenty fresh-frozen cadaveric knees were dissected and tested. Femoral and tibial footprints of the ALL were recorded. Pivot shift and Lachman tests were measured with KiRA. Results: The prevalence of ALL was 100%. The average distance of the tibial footprint to the tip of the fibular head was 19.85 ± 3.41 mm; from the tibial footprint to Gerdy's tubercle (GT) was 18.3 ± 4.19 mm; from the femoral footprint to the lateral femoral epicondyle was 10.25 ± 2.97 mm. ALL's footprint distance was the longest at 30° of flexion (47.83 ± 8.05 mm, p < 0.01) in a knee with intact ALL-ACL and neutral rotation. During internal rotation, the footprint distance was the longest at 30° of flexion (50.05 ± 8.88 mm, p < 0.01). Internal rotation produced a significant increase at all three angles after ACL-ALL were transected (p = 0.022), where the footprint distance was the longest at 30° of flexion (52.05 ± 7.60 mm). No significant difference was observed in KiRA measurements between intact ALL-ACL and ALL-transected knees for pivot shift and Lachman tests. However, ACL-ALL-transected knees showed significant differences compared to the intact ALL-ACL and ALL-transected knees (p < 0.01). Conclusions: The ALL was identified as a distinct ligament structure with a 100% prevalence in this cadaveric study. The ALL plays a protective role in internal rotational stability. An isolated ALL transection did not significantly affect the ALL footprint distances or functional stability tests. Therefore, the ALL is thought to act as a secondary supportive stabilizer for rotational stability of the knee joint in conjunction with the ACL.

Geometric variation of the human tibia-fibula: a public dataset of tibia-fibula surface meshes and statistical shape model.

Variation in tibia geometry is a risk factor for tibial stress fractures. Geometric variability in bones is often quantified using statistical shape modelling. Statistical shape models (SSM) offer a method to assess three-dimensional variation of structures and identify the source of variation. Although SSM have been used widely to assess long bones, there is limited open-source datasets of this kind. Overall, the creation of SSM can be an expensive process, that requires advanced skills. A publicly available tibia shape model would be beneficial as it enables researchers to improve skills. Further, it could benefit health, sport and medicine with the potential to assess geometries suitable for medical equipment, and aid in clinical diagnosis. This study aimed to: (i) quantify tibial geometry using a SSM; and (ii) provide the SSM and associated code as an open-source dataset. Lower limb computed tomography (CT) scans from the right tibia-fibula of 30 cadavers (male n = 20, female n = 10) were obtained from the New Mexico Decedent Image Database. Tibias were segmented and reconstructed into both cortical and trabecular sections. Fibulas were segmented as a singular surface. The segmented bones were used to develop three SSM of the: (i) tibia; (ii) tibia-fibula; and (iii) cortical-trabecular. Principal component analysis was applied to obtain the three SSM, with the principal components that explained 95% of geometric variation retained. Overall size was the main source of variation in all three models accounting for 90.31%, 84.24% and 85.06%. Other sources of geometric variation in the tibia surface models included overall and midshaft thickness; prominence and size of the condyle plateau, tibial tuberosity, and anterior crest; and axial torsion of the tibial shaft. Further variations in the tibia-fibula model included midshaft thickness of the fibula; fibula head position relative to the tibia; tibia and fibula anterior-posterior curvature; fibula posterior curvature; tibia plateau rotation; and interosseous width. The main sources of variation in the cortical-trabecular model other than general size included variation in the medulla cavity diameter; cortical thickness; anterior-posterior shaft curvature; and the volume of trabecular bone in the proximal and distal ends of the bone. Variations that could increase the risk of tibial stress injury were observed, these included general tibial thickness, midshaft thickness, tibial length and medulla cavity diameter (indicative of cortical thickness). Further research is needed to better understand the effect of these tibial-fibula shape characteristics on tibial stress and injury risk. This SSM, the associated code, and three use examples for the SSM have been provided in an open-source dataset. The developed tibial surface models and statistical shape model will be made available for use at: https://simtk.org/projects/ssm_tibia.

Isolated right peroneal mononeuropathy after silent SARS-CoV-2 infection in a child: Case report and review of the literature

Introduction: Peroneal neuropathy is considered as the most common mononeuropathy of the lower extremities, albeit with limited medical documentation. Risk factors include local injuries or recurrent minor trauma, surgery, weight loss, habitual leg crossing, other prolonged postures, or application of inappropriately fitted orthopedic devices that lead to uninterrupted pressure at the fibular head, intoxication, bicycle riding, prolonged anesthesia, lengthy hospitalization, other underlying neuropathies, diabetes mellitus, exposure to cold and irradiation and infection by neurotropic viruses. Case Report: We present a 4-year-old non-immunocompromised boy with an isolated right foot drop. At presentation, he had a characteristic walking that resulted from the inability to bend his right foot upward at the ankle. The foot drop developed gradually over the last week and was not accompanied by other symptoms. A careful history and appropriate serologic and imaging studies ruled out common causes of peroneal neuropathy except for SARS-CoV-2. Indeed, a high titer of specific IgG antibodies to this new coronavirus was detected, despite no history of prior immunization. Conclusion: Peroneal neuropathy may represent one of the many neurological sequelae of infection with SARS-CoV-2; physicians should be aware of this.