Intermediate ray deficiency—a new type of lower limb hypoplasia

Objective

Diagnosis of fibular hemimelia is based on the identification of absence or shortening of the fibula in relation to the tibia. Despite the existence of different classifications of this congenital deficiency, certain morphological forms defy proper classification. One such form is absence of foot rays with leg shortening in the presence of an entire fibula. In these cases, foot morphology suggests that central foot rays, not lateral ones, are affected by the deficiency; thus justifying the hypothesis concerning the existence of a separate type of hypoplasia, which may be named “intermediate ray deficiency” (IRD).

Materials and methods

Nine patients with IRD, with an average age of 9.4 years at diagnosis (2.9–15), were analyzed. Clinical and radiographic parameters of the leg and foot were recorded according to the Stanitski classification of fibular hemimelia. The position of the lateral and medial malleoli was assessed. Axial alignment was analyzed according to the Paley method.

Results

The number of foot rays in eight cases was 4, while in one case, it was 3. Talocalcaneal synostosis was observed in seven cases. The shape of the ankle joint was spherical in six cases, horizontal in two cases and valgus in one case. The position of the lateral malleolus was slightly higher compared to normal. An average functional leg length discrepancy was 4.4 cm. The average percentage of fibular shortening was 9.5 %, tibial shortening 8.7 % and femoral shortening 3.3 %. In all of the cases, slight knee valgus was observed on the femoral level (average 3.3°) and tibial level (average 2.0°). As a result, criteria for IRD diagnosis were proposed.

Conclusion

“Intermediate ray deficiency” might be defined as a separate type of lower limb hypoplasia.     

Grebe syndrome with bilateral fibular hemimelia and thumb duplication

Grebe syndrome is a rare recessively inherited form of short-limbed dwarfism. Among the skeletal anomalies reported in the past, complete fibular hemimelia and thumb duplication have not been documented. We report a case of Grebe syndrome with these associated anomalies and review the various skeletal anomalies reported in the literature related to this syndrome. Awareness of the skeletal anomalies that can occur in this syndrome should enable an accurate diagnosis.     

Force measurements on the fibular collateral ligament, popliteofibular ligament, and popliteus tendon to applied loads

BACKGROUND: Little information is known about the forces seen on the main individual structures of the posterolateral knee to applied loads. This information is needed to determine which structures should be reconstructed and also the relative strengths needed for reconstruction grafts. PURPOSE: To determine in vitro forces in the fibular collateral ligament, popliteofibular ligament, and popliteus tendon for various posterolateral knee loading conditions. STUDY DESIGN: Cadaveric study. RESULTS: The fibular collateral ligament was loaded in varus, internal rotation, and external rotation. The highest amount of force seen on the fibular collateral ligament was at 0 degrees of knee flexion with external rotation, with the mean load response to external rotation significantly less at 90 degrees . Fibular collateral ligament varus load response at 0 degrees , 30 degrees , and 60 degrees was fairly constant, with a significant decrease at 90 degrees compared to 30 degrees of knee flexion. The popliteus tendon and popliteofibular ligament were loaded with an external rotation moment and were noted to have similar loading patterns. The mean load response on both the popliteus tendon and the popliteofibular ligament peaked at 60 degrees of knee flexion. The mean popliteus tendon and popliteofibular ligament load response at 0 degrees was significantly less than the mean load response at 30 degrees , 60 degrees , and 90 degrees of knee flexion. CONCLUSIONS: High relative loads were seen on the fibular collateral ligament with varus and external rotation and on the popliteus tendon and popliteofibular ligament, with external rotation. A reciprocal relationship of load sharing in external rotation depending on knee flexion angle was revealed that has not been previously reported. The force on the fibular collateral ligament with external rotation loads was higher than the load on the popliteus complex at lower flexion angles, with the popliteus complex having higher load sharing at 60 degrees and 90 degrees of knee flexion. These results provide a measure of the potential for failure of these structures with joint loading and guidelines for both graft strength requirements for surgical reconstructions and postoperative rehabilitation protocols.     

Bilateral Transverse (Bowdler) Fibular Spurs with Hypophosphatasia in an Adolescent Girl

Hypophosphatasia is a clinically heterogeneous inheritable disorder characterized by defective bone mineralization and the deficiency of serum and tissue liver/bone/kidney alkaline phosphatase activities. Due to the mineralization defect of the bones, various skeletal findings can be radiologically observed in hypophosphatasia. Bowing and Bowdler spurs of long bones are the characteristic findings. The Bowdler spurs reported on in the previous pertinent literature were observed in the perinatal aged patients and these lesions have rarely involved adolescents. We herein report on a 14-year-old girl with fibular Bowdler spurs.     

Consistent arterial abnormalities associated with a variety of congenital malformations of the human lower limb

A number of seemingly unrelated congenital deformities of the lower limb have been presented which include clubfoot, fibular deficiency, tibial aplasia, and diplopodia. Although the bony morphology in these limbs is quite different, they all share a strikingly similar arterial pattern, that being deficiency or absence of the anterior tibial artery, and of its derivative, the dorsal pedis artery. Since all of these diverse conditions share a similar aberrant arterial pattern, we suspect that the arterial changes are important in the pathogenesis of those conditions. Study of the soft tissue anatomy of these specimens suggests that the etiologic teratogenic event occurred early in embryonic development. In those limbs that contain the remnant of a missing structure, it is concluded that injury occurred after the mesenchyme was instructed to form that structure. These are termed "post-specification" defects. In those circumstances where limb duplication occurs, the injury affected the signal before instruction of mesenchyme to develop into a specific structure was completed and these abnormalities are termed "pre-specification" malformations. The musculotendenous and neurologic abnormalities seem to be reactive to the pre-existing bony pattern.     

Anterolateral dislocation of the head of the fibula in sports

Traumatic anterolateral dislocation of the fibular head is an uncommon sports injury which is easily overlooked. Seventeen cases have been collected during private practice over the years. The typical mechanism of injury is a fall on the affected flexed knee with the leg adducted under the body and the ankle inverted. On physical examination there is an obvious bony prominence laterally of the fibular head and varying disability with activities; there is no significant effusion or signs of internal knee derangement or instability. Comparison identical radiographic views are necessary to confirm the diagnosis: on the anteroposterior view the fibular head is displaced laterally and the proximal interosseous space is widened; on the lateral view there is a greater overlap of the fibula on the tibia on the affected side. Peroneal nerve and ankle injuries can occur concomitantly with anterolateral proximal tibiofibular dislocation. Treatment options are closed or open reduction acutely and local strapping or fibular head resection for chronic cases based upon time of presentation and disability.     

Lateral ankle fracture with missed proximal tibiofibular joint instability (Maisonneuve injury)

We present a case of a soccer player who sustained a lateral ankle fracture and the associated proximal anterolateral tibiofibular joint instability (Maisonneuve injury) was overlooked. After a non-contact injury the (incomplete) diagnosis of a lateral malleolar fracture (type Weber B, AO 44-B1) was made and the patient was surgically treated with open reduction and internal fixation including a distal syndesmosis screw. After removal of the syndesmosis screw (six weeks after surgery) the patient suffered from activity-related pain around the fibular head. After thorough clinical and radiologic examination, temporary screw transfixation of the fibular head and capsular repair under meticulous fluoroscopic control of fibular rotation helped to restore patient’s sport activity level. This case report emphasizes the importance of precise clinical examination for detection of a proximal tibiofibular joint instability. Restoration of a well functioning and stable proximal tibiofibular joint may be difficult to achieve in previously operated and missed instabilities. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Posterolateral corner reconstruction for posterolateral rotatory instability combined with posterior cruciate ligament injuries: comparison between fibular tunnel and tibial tunnel techniques

The aim of this study was to compare the results of two different methods of posterolateral corner reconstruction (fibular head tunnel versus tibial tunnel), performed at the same time as a posterior cruciate ligament reconstruction. Between January 1999 and October 2003, 47 patients underwent tensioning of a remnant posterior cruciate ligament and anterolateral bundle reconstruction along with a posterolateral corner reconstruction using a fibular head bone or tibial bone tunnel. Thirty-nine patients determined to be eligible were enrolled in this retrospective study after a minimum follow-up duration of 2 years. The average duration of follow-up was 35.3 months (range 24–70 months). Satisfactory results were achieved in 32 patients (82%) according to the International Knee Documentation Committee(IKDC) scores, and 29 patients (74%) had restored external rotational stability. The fibular head tunnel was superior to the tibial tunnel method in terms of operation time (43.0 ± 15.7 vs. 66.6 ± 9.4 min, respectively, P < 0.001) and improved rotational stability (85 vs. 65%, respectively, P = 0.007). However, there were no significant differences seen in anteroposterior stability and clinical assessments [Orthopädische Arbeitsgruppe Knie (OAK) P = 0.277 and IKDC scores P = 0.564]. In grade 2 chronic posterolateral rotatory instability with little or no varus instability associated with injury to the posterior cruciate ligament, a posterolateral reconstructive procedure with a single sling through the fibular tunnel offers advantages of less surgical morbidity and operation time, as well as better rotational stability, over reconstruction through the tibial tunnel.     

Arcuate sign of posterolateral knee injuries: anatomic,radiographic, and MR imaging data related to patterns of injury

Objective The arcuate sign is considered a pathognomonic sign for injuries of the posterolateral (PL) corner of the knee. The purpose of our study was to identify different patterns of injury to the fibular head that may associate with injuries to specific ligaments and tendons of the PL corner of the knee. The anatomic relations between the insertions of fibular collateral ligament (FCL), biceps femoris tendon (BFT), popliteofibular ligament (PFL), and arcuate ligament in normal cadaveric knees were also investigated.Design and patients Magnetic resonance imaging was performed in two cadaveric knees which subsequently were dissected. Radiopaque markers were placed upon the fibular insertions of the FCL, BFT, PFL, and arcuate ligament in the dissected knees, and knee radiographs were then obtained. Twelve patients with radiographic or MR imaging evidence of isolated injury to the PL corner of the knee were retrospectively reviewed, with regard to avulsion fractures and marrow edema in the fibular head and the integrity of the ligaments of the PL corner of the knee.Results and conclusions The PFL and arcuate ligament were seen to attach directly to the posterior and medial aspect of the styloid process of the fibular head. The FCL and BFT attached as a conjoined structure on the lateral aspect of the fibular head lateral, anterior and inferior to the attachment site of the PFL and arcuate ligament. Injury to the arcuate ligament or PFL was diagnosed in 8 patients who presented with a small avulsion fracture of the styloid process of the fibula (n=2), bone marrow edema in the medial aspect of the fibular head (n=3), or both (n=3). In 4 patients with injury to the conjoined tendon or FCL, a larger avulsion fragment and more diffuse proximal fibular edema were seen. Radiographic and MR imaging findings in injuries of the posterolateral corner of the knee may suggest injury to specific structures inserting in the fibular head.Presented at the 87th Annual Meeting of the Radiologic Society of North America, 2001.     

Isometry of the lateral collateral and popliteofibular ligaments and techniques for reconstruction using a free semitendinosus tendon graft

Injuries to the lateral and posterolateral aspects of the knee are likely more common than appreciated. If theseinjuries are not recognized and treated, they may result in suboptimal results when treating injuries to the anterior cruciate ligament and posterior cruciate ligament. The treatment options for injuries to the lateral and posterolateral structures include primary repairs, primary repairs with augmentation, tightening of existing structures, and the creation of structural restraints from the lateral femoral epicondyle to either the posterolateral tibia or the fibular head. Reconstructive procedures to the fibular head offer advantages over those to the posterolateral tibia in that they are more optimally positioned to resist varus and posterolateral rotations, and tissue from the epicondyle to the posterior aspect to the fibular head maintains near isometry through a functional range of knee motion. A free semintendinosus tendon graft can be used to reconstruct the lateral collateral ligament and popliteofibular ligaments with minimal morbidity. This procedure can be used as an isolated procedure or in combination with other reconstructive procedures or primary repairs.     

Posterolateral instability of the knee: evaluation, treatment, results

Injuries to the fibular collateral ligament and posterolateral corner are uncommon, and are usually associated with other ligamentous injuries-in particular, the anterior cruciate ligament and/or posterior cruciate ligament, leading to significant functional impairment. The most common mechanism of injury for this area of the knee involves a combined hyperextension and varus force that is frequently of high energy. As these injuries occur typically in the setting of a multiligament-injured knee, the diagnosis and surgical reconstruction can be extremely challenging. This chapter will discuss the diagnosis of these injuries, including physical examination and imaging techniques, surgical timing, technical considerations, current controversies in management, and postoperative rehabilitation.     

Tibial and fibular developmental fields defects

Malformations of the lower limbs are rare and heterogeneous anomalies. To explain the diversity and complexity of these abnormalities, authors introduced the concept of tibial and fibular developmental fields. Defects in these fields are responsible for different malformations, which have been described, to our knowledge, in only one report in the radiology literature. We present a case of a newborn with femoral bifurcation, absent fibulae and talar bones, ankle and foot malformations, and associated atrial septal defect. Our case is an example of defects in both fibular and tibial developmental fields. Received: 6 August 1998; Revision received: 26 January 1999; Accepted: 27 January 1999     

Peroneal tendon injuries: CT analysis

Computed tomographic (CT) evaluation of the peroneal tendons was obtained in 25 normal ankles and 30 abnormal ankles studied for trauma. The tendons and associated soft-tissue and bony structures, such as the calcaneofibular ligament, superior and inferior peroneal retinacula, fibular groove, and peroneal tubercle, which have heretofore evaded documentation on routine radiographs, are illustrated and discussed. Special attention is given to normal variations such as convex fibular tip and enlarged peroneal tubercle, which predispose the peroneal tendons to abnormal mechanical stresses. Examples of CT-established peroneal tendon abnormalities in the 30 cases examined are also demonstrated. These abnormalities include subluxation, dislocation, entrapment, and tenosynovitis of the peroneal tendons. The authors believe CT has proved to be an extremely useful and relatively noninvasive imaging tool for the evaluation of peroneal tendon injuries.     

Treatment of Ankle Sprains With External Compression and Early Mobilization

In brief: Edema associated with the inversion ankle sprain can be minimized by using a U- shaped compression pad held in place against the soft tissue around the fibular malleolus by an elastic wrap or tape. Control of edema allows earlier mobilization of the ankle joint, which reduces recovery time and permits the earliest possible return to sports participation. Factors to be considered in the construction of a compression pad include shaping, firmness, and conformability to the contours of the ankle and foot. Optimal results are obtained through continuous use of a U-shaped pad beneath an adjustable form of compression for as long as the potential for edema exists.     

Ligamentous injury of the lower tibiofibular syndesmosis: radiographic evidence

A retrospective analysis of the ankle radiographs of 86 patients with disruptions of the distal tibiofibular syndesmotic ligaments and comparison with radiographs of 100 patients with normal ankles revealed several findings useful in identifying these lesions. These observations included location and character of lateral malleolar or fibular fractures, avulsions of the tibial or fibular syndesmotic attachments, talar tilt or displacement, and distortion of the normal tibiofibular and tibiotalar relationships. Injuries to the ligamentous support of the ankle may be subtle and overlooked. Recognition of these findings and an understanding of the mechanisms of injury will facilitate radiologic diagnosis of syndesmotic injuries and will allow for surgical repair to prevent potential complications.     

Intraosseous ganglion cyst associated with neuropathy

 We present a case of expansile intraosseous ganglion of the fibular head with cortical break-through, which has not been previously reported. Also associated with this case, and not previously reported, is peroneal nerve compression, causing foot drop caused by the large expansile nature of the lesion.     

Structural properties of lateral collateral ligament reconstruction at the fibular head

BACKGROUND: Anatomical reconstruction of a ruptured lateral collateral ligament using allograft tissue secured within the fibular head with an interference screw has been described. HYPOTHESIS: Interference fixation at the fibular head does not reproduce the strength of the intact ligament. STUDY DESIGN: Controlled laboratory study. METHODS: Ten intact lateral collateral ligaments were tested to failure. The distal fixation of 11 ligaments reconstructed with a graft including a bone plug and 11 ligaments reconstructed with a graft without a bone plug were also tested. RESULTS: The reconstructed ligaments consistently failed at the fibular head. The intact specimens predominately failed through ligament rupture. The mean strength and stiffness values were 460 +/- 163 N and 82 +/- 25 N/mm, respectively, for the intact ligaments, 113 +/- 40 N and 36 +/- 10 N/mm, respectively, for reconstruction with a bone plug, and 135 +/- 81 N and 34 +/- 14 N/mm, respectively, for reconstruction without a bone plug. The strength and stiffness were significantly (P < .05) greater for the intact ligaments than for either reconstruction group. The variation in strength was significantly larger for reconstruction without a bone plug than for reconstruction with a bone plug. CONCLUSION: Tension applied to lateral collateral ligaments reconstructed using fibular interference fixation should be limited immediately after surgery. Soft tissue fixation should be employed with care because of the inconsistency in the failure strength. CLINICAL RELEVANCE: Although fibular interference fixation is increasingly being described in the literature, the properties of reconstructed lateral collateral ligaments have not previously been quantified.     

Avulsion fracture of the head of the fibula (the "arcuate" sign): MR imaging findings predictive of injuries to the posterolateral ligaments and posterior cruciate ligament

OBJECTIVE: The purpose of this study was to describe the significance of an avulsion fracture of the head of the fibula ("arcuate" sign) and its association with injuries of the knee on MR imaging. MATERIALS AND METHODS: We conducted a retrospective search of 2318 patients who underwent conventional radiography and MR imaging after an episode of knee trauma. Patients were included in this study if they had an avulsion fracture of the head of the fibula revealed on conventional radiography and underwent arthroscopy. Thirteen patients, all of whom were men, satisfied the inclusion criteria. Ten patients underwent further explorative surgery. The clinical, radiographic, MR imaging, and surgical findings were then reviewed. RESULTS: The avulsion fracture of the styloid process of the fibular head was apparently related to injuries of the arcuate complex in all 13 patients. Radiographically, the bony fragment was horizontally oriented and similar in size in most patients, ranging from 8 to 10 mm in length and from 2 to 5 mm in width. On MR imaging, the fibular avulsion was identified in 11 of the 13 patients. The other two patients had marrow edema in the fibular styloid process, although the avulsion fracture was not evident. All patients had injuries of the posterior cruciate ligament (six tibial avulsions, seven midsubstance tears). No patient had a tear of the anterior cruciate ligament. Disruption of the lateral collateral ligament was evident in seven patients, and one patient had a tear of the popliteal tendon. During surgery, six patients had disruption of the arcuate complex, but this disruption could not be identified on the MR images. CONCLUSION: An avulsion fracture of the fibular head generally involves the styloid process and causes injury of some of the major stabilizers in the posterolateral corner. Avulsion fractures are strongly associated with disruption of the posterior cruciate ligament.     

The clock face guide to peroneal intraneural ganglia: critical “times” and sites for accurate diagnosis

Objective  The aim of this study is to exploit the normal nature of peroneal nerve anatomy to identify constant magnetic resonance imaging (MRI) patterns in peroneal intraneural ganglia. Design  This study is designed as a retrospective clinical study. Materials and methods  MR images of 25 patients with peroneal intraneural ganglia were analyzed and were compared to those of 25 patients with extraneural ganglia and 25 individuals with normal knees. All specimens were interpreted as left-sided. Using conventional axial images, the position of the common peroneal nerve and either intraneural or extraneural cyst was determined relative to the proximal fibula and the superior tibiofibular joint using a symbolic clock face. In all patients, the common peroneal nerve could be seen between the 4 and 5 o’clock position at the mid-portion of the fibular head. In patients with intraneural ganglia, a single axial image could reproducibly and reliably demonstrate both cyst within the common peroneal nerve at the mid-portion of the fibular head (signet ring sign) between 4 and 5 o’clock and within the articular branch at the superior tibiofibular joint connection (tail sign) between 11 and 12 o’clock; in addition, cyst within the transverse limb of the articular branch (transverse limb sign) was seen at the mid-portion of the fibular neck between the 12 and 2 o’clock positions on serial images. Extraneural ganglia typically arose from more superior joint connections with the epicenter of the cyst varying around the entire clock face without a consistent pattern. There was no significant difference between the visual and template assessment of clock face position for all three groups (intraneural, extraneural, and controls). We believe that the normal anatomic and pathologic relationships of the common peroneal nerve in the vicinity of the fibular neck/head region can be established readily and reliably on single axial images. This technique can provide radiologists and surgeons with rapid and reproducible information for diagnosis and treatment planning. Conclusions  By using conventional bony anatomy as reference points (namely fibular neck and mid-portion of fibular head), standard axial images can be used to interpret key features of peroneal intraneural ganglia and to establish their accurate diagnosis (rather than extraneural ganglia) and pathogenesis from an articular origin (rather than from de novo formation), a fact that has important therapeutic implications. Because of the relative rarity of peroneal intraneural cysts and physicians’ (radiologists and surgeons) inexperience with them and the complexity of their findings, they are frequently misdiagnosed and joint communications are not appreciated preoperatively or intraoperatively. As a result, outcomes are suboptimal and recurrences are common.     

Tibial and fibular angles in homozygous sickle cell disease

Measurements of the tibial and fibular angles made on ankle radiographs of 34 patients with sickle cell disease were compared with those of 36 normal Nigerians. Widening of the fibular angle, which is an indication of tibiotalar slant, was demonstrated in about 79% of sickle cell disease patients. By using fibular angle measurements as an objective method of assessing subtle tibiotalar slant, it is concluded that the incidence of this deformity is much higher among sickle cell disease patients than previously reported. The mean values of tibial and fibular angles in normal Nigerians are higher than has been reported amongst Caucasians.