Common fibular nerve palsy due to the Fabella: A review.

One of the most common nerve palsies - common fibular nerve palsy - can be caused by the variant small sesamoid bone in the posterolateral compartment of the knee joint known as the fabella. We compared and reviewed all reported cases of common fibular nerve palsy due to fabellae in the English literature. Compression can develop spontaneously or post-surgically (total knee arthroplasty). Symptoms progress rapidly to complete foot drop. Among all the cases reviewed, 68.42% were males with a median age of 39.39 years. Fabella compression was more common in the left common fibular nerve (CFN) (63.16%). Both big (23 × 20 × 16 mm) and small (5 × 5 mm) fabellae can be responsible for compression. While diagnosis can be problematic, the treatment (either surgical fabellectomy or conservative) is relatively easy and brings quick improvement.

Fracture of the fabella with radiologic and MRI.

The fabella is an inconstant sesamoid bone. A handful of cases have been reported so far describing fabella fracture, usually involving high energy mechanism or stress fractures after total knee arthroplasty. This paper presents a fabella fracture in a man in his 40s after suffering a car crash, the clinical and radiographic presentation, treatment and complete recovery at 4-months follow-up.

Partial Excision of a Tibial Sesamoid Fracture Nonunion in a Patient with Congenital Absence of Fibular Sesamoid: A Case Study.

BACKGROUND: Hallucal sesamoid injuries occur in approximately 5% to 10% of foot and ankle injuries. Most cases can be treated conservatively. However, when nonoperative management fails, surgical intervention is warranted. METHODS: The present case involved a 17-year-old female high school senior who presented to the clinic with right hallux pain. Radiographs were obtained and revealed congenital absence of the fibular sesamoid and evidence of a minimally displaced avulsion fracture involving the proximal medial tibial sesamoid. Treatment was complicated by the congenital absence of the fibular sesamoid and by a high activity level. RESULTS: After conservative treatment failure, the patient underwent partial excision of her tibial sesamoid. She was followed for 1.5 years after initial presentation to our clinic. The patient was able to return to daily activities; however, she was not able to return to softball competitively due to pain. CONCLUSIONS: We hypothesize she was unable to return to softball because the absence of a sesamoid can decrease push-off strength. We recommend that providers treating athletes educate their patients on the possible loss of strength and take this into account when creating a treatment plan.

A modified minimally invasive osteotomy for hallux valgus enables reduction of malpositioned sesamoid bones.

BACKGROUND: The current minimally invasive distal metatarsal osteotomy for hallux valgus (HV) is V-shaped, which prevents the correction of the rotational metatarsal head deformity and reduction of the sesamoid bones. We sought to determine the optimal method for sesamoid bone reduction during HV surgery. METHODS: We reviewed the medical records of 53 patients who underwent HV surgery between 2017 and 2019 using one of three techniques: open chevron osteotomy (n = 19), minimally invasive V-shaped osteotomy (n = 18), and a modified straight minimally invasive osteotomy (n = 16). The sesamoid position was graded using the Hardy and Clapham method on weight-bearing radiographs. RESULTS: When compared to open chevron and V-shaped osteotomies, the modified osteotomy resulted in significantly lower postoperative sesamoid position scores (3.74 ± 1.48, 4.61 ± 1.09, and 1.44 ± 0.81, respectively, P < 0.001). Furthermore, the mean change in postoperative sesamoid position score was greater (P < 0.001). CONCLUSION: The modified minimally invasive osteotomy was superior to the other two techniques in correcting HV deformity in all planes, including sesamoid reduction.

Correlations of Sesamoid Bone Subluxation with the Radiologic Measures of Hallux Valgus and Its Clinical Implications.

Background and Objectives: Hallux valgus is one of the most common chronic foot complaints, with prevalences of over 23% in adults and up to 35.7% in older adults. However, the prevalence is only 3.5% in adolescents. The pathological causes and pathophysiology of hallux valgus are well-known in various studies and reports. A change in the position of the sesamoid bone under the metatarsal bone of the first toe is known to be the cause of the initial pathophysiology. Purpose: The relationships between the changes in the location of the sesamoid bone and each radiologically measured angle and joint congruency in the hallux valgus remain as yet unknown. Therefore, this study investigated the relationships of sesamoid bone subluxation with the hallux valgus angle, intermetatarsal angle, and metatarsophalangeal joint congruency in hallux valgus patients. The goal is to know the hallux valgus angle, the intermetatarsal angle, and metatarsophalangeal joint congruency's correlation with hallux valgus severity and prognosis by revealing the relationship between each measured value and sesamoid bone subluxation. Materials and Methods: We reviewed 205 hallux valgus patients who underwent radiographic evaluation and subsequent hallux valgus correction surgery in our orthopedic clinic between March 2015 and February 2020. Sesamoid subluxation was assessed using a new five-grade scale on foot radiographs, and other radiologic measurements were assessed, such as hallux valgus angle, the intermetatarsal angle, distal metatarsal articular angle, joint congruency, etc. Conclusions: Measurements of the hallux valgus angle, interphalangeal angle, and joint congruency exhibited high interobserver and intraobserver reliabilities in this study. They also showed correlations with sesamoid subluxation grade.

Locking of the Metacarpophalangeal Joint of the Thumb Caused by Entrapment of the Radial Sesamoid Bone.

Locking of metacarpophalangeal (MCP) joints of the thumb may be a consequence of dorsal subluxation from hyperextension injury. The joint is locked in mild hyperextension and cannot flex actively or passively. We report four patients with locked MCP joint of the thumb due to radial sesamoid entrapment after hyperextension or forced flexion injury. All patients had a prominent radial condyle of the metacarpal bone. Three patients had a deformity of the longitudinal groove on which the sesamoid was overlaid. The radial sesamoid was entrapped proximal to the radial condyle which could result in limited extension and hinged flexion of the joint. Excision of the radial sesamoid could release the locked joint. The radial sesamoid should be assessed if the motion of the thumb MCP joint is limited after flexion or extension injury. Level of Evidence: Level V (Therapeutic).

Open Reduction and Screw Fixation of a Diastatic Bipartite Hallux Sesamoid in Turf Toe Injury: A Case Report.

We present a case of a 25-year-old male professional soccer player who complained of severe pain over the first metatarsal head after opponent contact during a soccer game. Clinical findings showed swelling and tenderness. Initial radiographs showed a diastasis of a bipartite medial sesamoid between the fragments as compared to radiographs taken 4 years earlier of the same foot. A computed tomography scan was performed objectifying the widened interval and also showing an angulation of the proximal fragment. Open reduction and screw fixation were performed, leading to adequate positioning of the 2 bipartite fragments. The patient showed good clinical recovery and returned to the same performance level. Turf toe injury with diastasis of a medial bipartite sesamoid can be treated successfully with this operative technique.Levels of Evidence: Level V: Case report.

Concentrated Bone Marrow Aspirate Injection for Hallux Sesamoid Disorders.

Concentrated bone marrow aspirate (CBMA) offers an alternative to sesamoid resection in end stage sesamoid pathology. CBMA potentiates the anti-inflammatory effect, stimulates local tissue regeneration and osteogenesis, when injected into bone. The purpose of this study is to evaluate the functional outcomes in a cohort of athletes following CBMA injection for the treatment of hallux sesamoid disorders. A retrospective case series of consecutive patients treated with CBMA injection for hallux sesamoid disorders were identified. Radiographs, Foot and Ankle Outcome Scores (FAOS), and Visual Analogue Scale (VAS) score were collected pre- and postinjections. Descriptive statistics were presented as the mean and standard deviation for continuous variables and frequency as percentages for categorical variables. Fifteen consecutive patients with were included with a mean follow-up time of 20.1 (range 12-34) months. Significant improvement in all scoring subscales of the FAOS and VAS score was noted preinjection compared to final follow-up postinjection (p < .001). Eight of 11 patients that were involved in sports prior to the CBMA injection returned to play, with 7 successfully returning to preinjury level status. Three patients required further treatment (20%). The case series suggests that CBMA injection is a safe and effective treatment option for hallux sesamoid disorders with a high rate of return to play.

Sesamoidectomy in Athletes: Outcomes From 2-Centers.

Sesamoid pain can arise from avascular necrosis, fracture, osteochondrosis, and advanced degeneration. Disorders of the sesamoids in athletes can be debilitating. Total sesamoidectomy of the involved sesamoid is considered an effective surgical treatment when conservative measures have failed. There is limited literature evaluating the outcome of sesamoidectomy in athletically active patients. Our 2-center study reports on 68 patients (70 procedures; 2 male patients were operated on both feet in separate procedures approximately 3 years apart; 41 (58.6%) tibial and 29 (41.4%) fibular sesamoidectomies; 24 males and 44 females, average age 28.4 ± 12.2 years) who underwent total sesamoidectomy from 01/2001 to 12/2019. In our cohort, the average time to return to activity (RTA) was 11.1 ± 5.1 weeks, with no statistically significant difference between gender and age, or between fibular and tibial sesamoidectomy in relation to RTA. There was a minimum follow-up of 1 year, with an average of 106.6 ± 66.6 months. The total incidence of complication rate was 5.7%. In athletes in whom conservative management has failed, sesamoidectomy is safe, and allows predictable return to their chosen sport. To our knowledge, none of the patients subsequently developed pathology to the remaining sesamoid.

Arthroscopic Sesamoidectomy for Hallux Sesamoid Disorders.

In this retrospective case series, we aimed to study arthroscopic sesamoidectomy, including surgical methods, clinical outcomes, and complications. We retrospectively reviewed the medical records of patients with hallux sesamoid disorders who underwent arthroscopic sesamoidectomy from July 2015 to July 2017. The visual analog scale for rating pain, Japanese Society for Surgery of the Foot scale scores, number of days taken to return to normal daily living, number of months taken to return to playing sports, and complications were analyzed. The mean follow-up duration was 3.2 years. Among 14 patients, there were 8 females and 6 males (median age: 39 years). The mean visual analog scale score improved from 75.4 to 14.3 mm; the mean Japanese Society for Surgery of the Foot score improved from 55.2 to 88.0 points. The mean time to return to activities of daily living was 5.3 days. Among the 5 patients who played sports, 3 and 2 patients resumed playing sports at 3 and 12 postoperative months, respectively. Complications included wound pain (n = 4), discomfort in severe weather (n = 4), numbness (n = 3), pain in the sole other than in the ball of the foot (n = 2), pain during hallux dorsiflexion (n = 2), residual sesamoid discomfort (n = 1), swelling (n = 1), toe-in gait (n = 1), and metatarsal head bone marrow edema (n = 1). Despite good clinical outcomes of arthroscopic sesamoidectomy, patients should be made aware of the many potential complications of this procedure prior to surgery.

Treatment of Fabella syndrome with arthroscopic fabellectomy: a case series and literature review.

BACKGROUND: The fabella is a sesamoid bone in the posterolateral capsule of the human knee joint. In quadrupedal mammals, the fabella is believed to have a role similar to the patella in redirecting extension forces of the knee joint from one point to another. In bipeds, the fabella is not touching the back of the bent knee, and therefore the role in redirecting forces declines. Posterolateral knee pain can be associated with the irritation between the fabella and lateral femoral condyle, a phenomenon also known as fabella syndrome. In cases that are unresponsive to conservative management, surgical fabellectomy can be a successful treatment option. Among the surgical approaches, open resection is most commonly seen. There are also literature reporting arthroscopic-assisted open resection, but seldom mentioned the all-arthroscopic fabellectomy. CASE PRESENTATION: We present 3 patients with a long history (> 12 month) of posterolateral knee pain under suspicion of different pain origins. The diagnosis of fabella impingement was eventually made by ruling out of other causes. All the patients underwent all-arthroscopic fabellectomy for diagnosis and treatment. Investigations of the resected fabella suggested chronic impingement with apparent osteophyte formation and cartilage wearing of the articular side. All patients have been continually followed up at our outpatient department and reported to be pain free after the procedure. CONCLUSIONS: In the patients presenting posterolateral pain, fabella syndrome cannot be ignored due to its relative higher presence in Asian population. In our experience, the all-arthroscopic fabellectomy offers a smaller wound size, less post-operative pain, fewer days of hospitalization and quicker time to rehabilitation for the patients with chronic posterolateral knee pain caused by fabella syndrome.

Fungal osteitis of the axial aspect of the mid body of the medial proximal sesamoid bone in a horse.

The satisfactory outcome of fungal osteitis in an 8-year-old American Quarter Horse is described. The horse was admitted with a grade 4 out of 5 lameness and exhibited metacarpophalangeal synovial effusion, indicative of a mild suppurative inflammation. Results of initial radiographic and ultrasonographic examination were unremarkable. Intra-articular anesthesia of the metacarpophalangeal joint allowed localization of the insult. It was not until day 6 of hospitalization when lytic changes on the axial aspect were observed on radiographic examination. Arthroscopic examination permitted identification and debridement of the affected bone. Fungal culture of the bone yielded Pleosporales spp. The horse was sound at the time of discharge after 12 days of hospitalization. No complications occurred in the post-operative period and the horse resumed his initial level of activity and competition in barrel racing. Key clinical message: To our knowledge, this is the first description of successful outcome of a fungal osteitis of the sesamoid bones following arthroscopic debridement. We hypothesize that the satisfactory outcome is associated with early recognition of the condition and aggressive debridement of the lesion arthroscopically.

Ostéite fongique de la face axiale du milieu du corps de l'os sésamoïde proximal médial chez un cheval. L'évolution satisfaisante de l'ostéite fongique chez un Quarter Horse américain de 8 ans est décrite. Le cheval a été admis avec une boiterie de grade 4 sur 5 et présentait un épanchement synovial métacarpo-phalangien, indicatif d'une légère inflammation suppurée. Les résultats de l'examen radiographique et échographique initial étaient sans particularité. L'anesthésie intra-articulaire de l'articulation métacarpo-phalangienne a permis de localiser le site affecté. Ce n'est qu'au jour 6 de l'hospitalisation que des modifications lytiques de la face axiale ont été observées à l'examen radiographique. L'examen arthroscopique a permis l'identification et le débridement de l'os affecté. La culture fongique de l'os a donné des Pleosporales spp. Le cheval était sain au moment de sa sortie après 12 jours d'hospitalisation. Aucune complication n'est survenue dans la période post-opératoire et le cheval a repris son niveau initial d'activité et de compétition en course de barils.Message clinique clé :A notre connaissance, il s'agit de la première description de l'issue positive d'une ostéite fongique des os sésamoïdes après débridement arthroscopique. Nous émettons l'hypothèse que le résultat satisfaisant est associé à une reconnaissance précoce de l'affection et à un débridement agressif de la lésion sous arthroscopie.(Traduit par Dr Serge Messier).

Common Peroneal Nerve Palsy Due to Giant Fabella After Total Knee Arthroplasty.

BACKGROUND: Common peroneal nerve palsy (CPNP) is a rare but serious complication following primary total knee arthroplasty (TKA). The common peroneal nerve is one of the main molecules of the sciatic nerve. CPNP is a series of symptoms caused by common peroneal nerve injury due to paralysis and atrophy of the fibula and tibia muscles. The main clinical symptoms are: ankle joint unable to extend back, toe unable to extend back, foot droop, walking in a steppage gait, and foot dorsal skin sensation having decreased or disappeared. If treatment is not timely, severe cases may result in atrophy of the anterior tibia and lateral calf muscles. The risk factors for CPNP include mechanical stretching of the nerve, disruption of the blood supply to the nerve, and compression of the nerve. The CPNP should be treated in a timely manner and according to the cause. Its function should be restored as soon as possible to avoid serious adverse consequences. It has negative effects on patients' life and physical and mental health. To our knowledge, this is the first study to describe CPNP due to a giant fabella after TKA. CASE PRESENTATION: The present study reported on a 70-year-old female patient. The patient underwent a primary TKA of the right knee for osteoarthritis. Relevant examinations were conducted and the operation went smoothly. Three hours postoperation, a right partial CPNP was observed, with progressive aggravation over time. On palpation, there was a 2 × 2-cm fixed hard mass in the posterolateral aspect of the right knee, with mild tenderness to deep palpation. Radiographs demonstrated that a giant fabella was located at the posterolateral condyle of the right femur. Fabellectomy and neurolysis of the common peroneal nerve were performed. The peroneal nerve palsy resolved gradually after the operation. At 8-month follow up after fabellectomy and neurolysis, the function of the common peroneal nerve had fully recovered. CONCLUSIONS: The presence of giant feballa pressing on the common peroneal nerve should be considered when common peroneal nerve palsy occurs after TKA. Surgical exploration and release compression should be performed in a timely manner.

Fabella syndrome in an elite swimmer. / Síndrome de la fabela en un nadador de élite.

The fabella is a sesamoid bone present in 30% of the population and, in the majority of cases, it is shown in the proximal head of the lateral gastrocnemius articulating with the lateral femoral condyle. Fabella syndrome is an uncommon disease and it must be considered when dealing with posterolateral pain that increases with extension of the knee. Because of its rarity and underdiagnosis, the literature reports few articles relating to its therapeutic management. The articles reviewed demonstrate that conservative treatment has high recurrence rates, surgical excision being the most effective treatment to eradicate symptoms. We found exceptional articles in the literature related to the surgical treatment of fabella syndrome in professional athletes. In this article we report the surgical experience of a 21-year-old elite swimmer who achievedcomplete pain relief and fast recovery after surgical excision of the fabella.

Classification of Hallucal Sesamoid Bone Correlated with Hallux Valgus Severity.

The hallucal sesamoid bones (HSBs), having an important role in reducing load per unit area on the first metatarsal head, can be injured commonly which also affected the first metatarsophalangeal joint and the surrounding structure. Meanwhile, differences among each HSB type may be a major factor affecting the occurrence and development of HV. So far, many researchers had learned that there are three different conditions in hallucal sesamoid bone affecting the choice of clinical surgery corresponding to different solutions in clinic. Thus, it is necessary to study the anatomical morphological characteristics of the HSB which can be helpful in clinical diagnosis and treatment, especially hallux valgus (HV). 150 X-ray and three-dimensional (3D) computed tomographic (CT) images consist of 72 left and 78 right metatarsals were applied in this anatomic study between two variables and showed by a simple scatter plot. The first metatarsophalangeal joint is divided into four different types: type I (no HSB, 1.3%), type II (with one HSB, 0.07%), type IIIa (with two HSBs when THB is bigger, 28%), type IIIb (with two HSBs when FHB is bigger, 65.3%), and type IV (with three HSBs, 4.7%). There was no statistical difference between the left and right sides, except HVA, Meary, and pitch (P < 0.05); all a, b, c, d, and i have statistical difference between male and female (P < 0.05). Meanwhile, HVA and IMA and HVA and type group have a significant correlation. In summary, HVA and IMA and HVA and classification of HSBs have significant correlations. The classification and location of HSBs can be an important basis to choose operation methods and postoperation evaluation.

Arthroscopic Synovectomy and Excision of a Sesamoid in the Management of an Atypical Presentation of Avascular Necrosis of Bone: A Case Report.

Avascular necrosis of a sesamoid bone is a rare and incompletely understood entity. Furthermore, associated lesions secondary to sesamoid pathology have seldom been described in the literature. We report a case of avascular necrosis of the medial sesamoid, accompanied by severe synovitis of the first metatarsophalangeal joint, that was successfully managed with arthroscopic synovectomy and open excision of the sesamoid.

Intrinsic Fixation of the Tibial Sesamoid in First Metatarsophalangeal Joint Arthrodesis: A Cadaveric Study.

Nonunion rate of first metatarsophalangeal joint (MTP) joint arthrodesis is reportedly less than 6%, regardless of fixation type. Robust modern plating constructs aim to decrease incidence of nonunion while also allowing early postoperative weight-bearing. Quicker transition to weight-bearing postoperatively increases patient adherence, decreases adjacent joint stiffness, and reduces risk of deep vein thrombosis in the postoperative period. The purpose of this study was to investigate the effect tibial sesamoid fixation has on first MTP joint arthrodesis.

Functional and patient reported outcomes following lateral hallucal sesamoidectomy.

BACKGROUND: Lateral hallucal sesamoidectomy is an infrequently performed procedure indicated for patients with sesamoid pathology failing conservative treatment. Concerns exists regarding patient satisfaction, plantar scar pain, hallux malalignment and metatarsophalangeal joint (MTPJ) movement restriction following sesamoidectomy. This study aims to assess patient satisfaction after lateral hallucal sesamoidectomy via the plantar approach. METHODS: In this retropective study with prospective follow-up, all patients who underwent lateral hallucal sesamoidectomy between January 2004 and December 2017 were reviewed. Twelve patients (14ft.) were available for final assessment. Outcome measures were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) clinical rating scale and the Self-Reported Foot and Ankle questionnaire (SEFAS). Patients were assessed clinically and radiologically. The average postoperative follow-up was 111.5 months (range 28-177 months). RESULTS: All patients reported excellent outcome scores with a mean SEFAS score of 46.08 (range 43-48) and a mean AOFAS score of 92.33 (range 78-100) at final follow-up. All twelve patients reported their outcome as being excellent. No malalignment was noted clinically, however, three patients had a noticeable increase in the gap between the hallux and second toe when compared to the contralateral side. Range of motion at the MTPJ was preserved with a mean dorsiflexion of 80.83° (range 70-90°) and a mean plantarflexion was 25.83° (range 0-30°). None of the patients experienced any pain, discomfort or irritation related to the plantar scar. One patient developed neuroma like symptoms in the first web space. CONCLUSION: Lateral hallucal sesamoidectomy via a plantar approach is an effective and reliable treatment option as demonstrated by the high levels of patient satisfaction, preservation of function, excellent PROM scores and limited complications in this study. LEVEL OF EVIDENCE: Level 4.

An Acute Osteochondral Defect Secondary to Fabella Impaction: A Case Report.

CASE: A healthy 37-year-old man sustained a knee injury after performing a deep flexion maneuver while skiing and noted immediate knee pain and swelling. Because of persistent inability to fully extend his knee and persistent posterolateral knee pain, he was evaluated and noted to have an acute osteochondral defect of the posterolateral femoral condyle directly adjacent to his fabella. After a trial of nonoperative interventions, he elected to undergo an arthroscopic-assisted open excision of the fabella and a chondroplasty of the posterolateral femoral condyle defect. CONCLUSION: A traumatic osteochondral defect secondary to a lateral fabella impaction is a rare pathology but must be evaluated in patients performing deep flexion maneuvers who have persistent knee pain and mechanical symptoms. When there is a focal defect with increased edema of both the fabella and posterolateral femoral condyle, an arthroscopic chondroplasty and fabella excision is a valid treatment to return the patient back to desired activities.

Concomitant Dislocation of the Hallucal Interphalangeal Joint and Extra-Articular Dislocation of Its Sesamoid: A Case Report.

CASE: A 22-year-old man sustained closed dislocation of the hallucal interphalangeal joint (HIPJ). Painful limitation of movements persisted 2 months after closed reduction. Magnetic resonance imaging revealed dislocation of the hallucal interphalangeal joint sesamoid (HIPJS) from its intra-articular attachment on the superior surface of the plantar plate to an extra-articular subcutaneous location, plantar and lateral to the flexor hallucis longus tendon. The HIPJS was enucleated through a plantar approach, and the foot remains pain-free 18 months later. CONCLUSIONS: This case represents an unusual combination of HIPJ dislocation and extra-articular dislocation of its sesamoid. Raised awareness of the HIPJS, its normal anatomical location, and configuration will avoid delayed diagnosis.