Walther H.O. Bohne

The dynamics of peroneus brevis tendon splits: A proposed mechanism, technique of diagnosis, and classification of injury

The etiology of peroneus brevis splits is unclear. 16,26 Because longitudinal splits in the peroneus brevis tendon do not necessarily effect the integrity or strength of the tendon, it is difficult to ascertain whether or not injury to the peroneus brevis tendon is present. Recent clinical, anatomic, and histologic reports have suggested that the split develops from prolonged mechanical attrition within the fibular groove as a result of ankle trauma with resultant lateral ankle instability and incompetency of the superior peroneal retinaculum with resultant subluxation of the peroneal tendons. 15,17,22 –25 This cascade of events may result in splitting of the peroneus brevis tendon. The purpose of this paper was to report the investigation of the mechanism by which peroneus brevis splits develop, to describe a technique of diagnosis, and to propose a classification of injury. Peroneus brevis splits are the result of a dynamic mechanical insult at the fibular groove. Laxity of the superior peroneal retinaculum combined with peroneus longus mechanical compression causes the peroneus brevis to splay out and eventually split over the sharp posterior edge of the fibula. Anatomic factors, such as a shallow fibular groove (congenital convex groove) or the presence of an anomalous low-lying peroneus brevis muscle belly or peroneus quartus tendon, 4,7,25 may also play a role in this mechanism by interfering with the competence of the superior peroneal retinaculum.

Congenital Variations of the Peroneus Quartus Muscle: An Anatomic Study

There has been little research concerning this muscle since the 1920s, when Hecker 13,14 described this muscle to be present in (13%) of his dissections of cadaver legs. The purpose of our dissections was to establish the incidence of the peroneus quartus muscle, its origins, and insertions. One hundred and twenty-four legs from 65 fresh human cadavers were dissected under loupe magnification. When the peroneus quartus tendon was found, its origin, insertion, and anatomic relationship to the peroneus longus and peroneus brevis were observed. All specimens were sketched and photographed. The peroneus quartus muscle was present in 27 legs (21.7% of specimens). Its origins, insertions, and size varied. In 17 legs (63%) the muscle originated from the muscular portion of the peroneus brevis, and inserted on the peroneal tubercle of the calcaneus. The peroneal tubercle was hypertrophied at the insertion in most cases. The results of this study in general show that there was much higher incidence of the peroneus quartus muscle than Hecker claimed. Its course, origin, and insertion varied. Its tendon can be used for reconstructive procedures about the lateral aspect of the ankle, especially in anterior dislocation of the peroneal tendons and reconstruction of lateral ligaments.

Longitudinal attrition of the peroneus brevis tendon in the fibular groove: an anatomic study.

There has been little research concerning the attrition of the peroneus brevis tendon since Meyers observation in 1924. The purpose of our dissections was to establish the incidence of the attrition of the peroneus brevis tendon at the fibular groove, and observe the anatomical relationship of the tendon attrition to the bony anatomy of the distal fibula. One hundred and twenty-four fresh human cadavers ankles from 65 cadavers were dissected under loupe magnification. When attrition of the peroneus brevis was found, the extent of attrition was measured, and anatomic proximity of the tendon to distal fibular groove was observed. Evidence of other tendon attrition as well as the depth of the fibular groove was observed. Specimens which revealed attrition of the peroneus brevis were sketched and photographed. Attrition of the peroneus brevis tendon was found in 14 ankles (11.3% of specimens). The attrition was limited only to the peroneus brevis tendon, and in no specimens was the peroneus longus involved. The degree of tendon attrition varied from simple splaying out of the peroneus brevis in the fibular groove to longitudinal splits in the peroneus brevis tendon with significant fraying of the remaining halves of the tendon. The longitudinal ruptures in the peroneus brevis tendon averaged 1.9 cm (range 1–4 cm). In all cases, the central portion of the longitudinal split was centered over the distal tip of the fibula in the fibular groove. In no case was a complete rupture of the peroneus brevis tendon noted. There was gross evidence of chronic inflammation and synovitis in those ankles with attrition of the peroneus brevis tendon. The results of this study in general present a description of the incidence of peroneus brevis attrition, and when present, the variable degree of attrition, the anatomic relationship of the tendon attrition to the fibular groove, and the evidence of synovitis and chronic inflammation associated with tendon attrition. This incidence of occurrence has not been documented before. The significance of this finding is that chronic ankle pain disability may be related to attrition of the peroneus brevis tendon in the fibular groove.

Anatomy of the Achilles Tendon and Plantar Fascia in Relation to the Calcaneus in Various Age Groups

Ten adult cadaver feet, three neonatal feet, and the feet of two fetuses were dissected to investigate whether an anatomical continuity exists between the fibers of the Achilles tendon and the plantar fascia. Histologic sections of the feet were done in three age groups: neonate, persons in their mid-20s, and the elderly. As the foot ages, there appears to be continued diminution of the number of fibers connecting the Achilles tendon and plantar fascia. The neonate has a thick continuation of fibers, while the middle-aged foot has only superficial periosteal fibers that continue from tendon to fascia. The elderly feet show simply an insertion of fibers of both structures into the calcaneus with periosteum in between.

Longitudinal Splitting of the Peroneus Brevis Tendon: An Anatomic and Histologic Study of Cadaveric Material

Gross and microscopic examinations of 21 split and 10 intact cadaveric peroneus brevis tendons were performed in an effort to determine the pathogenesis of longitudinal splitting of this tendon. The split regions were centered over the posterior margin of the distal fibula and were characterized by splaying of the collagen bundles with accompanying proliferation of blood vessels and fibrovascular connective tissue. Inflammatory infiltrates were not present. Regions of the tendons that were not altered had normal cellularity and orientation of the collagen. The findings of this study suggest that the splitting of the tendon develops through a mechanical mechanism.

Lateral Ankle Instability as a Cause of Superior Peroneal Retinacular Laxity: An Anatomic and Biomechanical Study of Cadaveric Feet

The role of the competent superior peroneal retinaculum (SPR) as a primary restraint to peroneal tendon subluxation and mechanical attritional wear is clear. Injury to the SPR has classically been described as a dorsiflexion aversion movement of the ankle coupled with a forceful peroneal tendon reflex contraction. This mechanism, however, does not cause injury to the lateral collateral ligaments of the ankle and does not explain the coexistent findings of lateral ankle instability, laxity of the SPR, and concurrent peroneal tendon pathology. Anatomic studies reveal a parallel alignment of the calcaneal band of the SPR and the calcaneofibular ligament. A cadaveric model of ankle instability created by serial sectioning of the lateral collateral ligaments revealed increasing visual strain on the SPR with increasing degrees of ankle instability. These findings suggest the SPR serves as a secondary restraint to ankle inversion stress and that the force or forces that result in chronic ankle instability can also injure and attenuate the superior peroneal retinaculum.

Microvascular Anatomy of the Peroneal Tendons

The etiology of longitudinal splitting of the peroneus brevis tendon is unclear. It has been hypothesized that compressive load applied to the tendon as it passes through the fibular groove may compromise the vascularity of the tendon with resultant inhibition of the repair response and degeneration of tendon structure. To investigate this possibility, a study of the microvascularity of the peroneal tendons was undertaken. Twelve fresh, frozen cadaveric limbs were injected with India ink. The vascularity of the peroneal tendons was examined in situ and the tendons were harvested and cleared using a modified Spalteholz technique. The vascularity of the cleared tendons was evaluated utilizing a dissecting microscope. The vascular supply of the peroneal tendons arises from two posterolateral vincula, one for the peroneus longus tendon and one for the peroneus brevis tendon. These vincula are supplied by branches of the posterior peroneal artery. A zone of hypovascularity within the peroneus brevis or peroneus longus tendon correlating with the site of peroneus brevis splits was not found. There was no relationship between increasing age of specimens and alteration in vascular supply.

An Analysis of Outcome Measures Following the Broström-Gould Procedure for Chronic Lateral Ankle Instability

Background: The Broström-Gould procedure is a commonly recommended operative treatment for chronic ankle instability. Using standardized physician-based outcome scores, the results of this procedure have been uniformly excellent. Current scoring systems, however, do not adequately evaluate mechanical or functional instability. Therefore, outcome data may suggest greater success than is justified. Methods: A retrospective review was done of 73 patients who had isolated Broström-Gould repairs of the lateral ankle ligaments. The mean time to followup was 64 months. Both the AOFAS ankle-hindfoot score and the Short Form 36 (SF-36) were used to evaluate outcome.Results: The overall American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score was 95 of 100 points. Despite that, 17% of patients in the study had functional instability of the ankle that was not reflected in the AOFAS score. The mean physical component score of the SF-36 was 84% and reflected the presence of functional instability. Low correlations were found between the AOFAS ankle-hindfoot score and the SF-36 score. Conclusions: The current study identified a deficiency in the AOFAS score in evaluating functional ankle stability after the Broström-Gould procedure. A more meaningful analysis of outcomes can be expected using the SF-36 score. The data suggest that greater attention must be paid to functional rehabilitation after ankle stabilization surgery to obtain optimal outcome.

Foot and ankle injuries in the adolescent runner

Purpose of review To evaluate the increase in overuse injuries in the adolescent athlete, specifically sports-related injuries to the foot and ankle of the adolescent runner. Factors affecting these injuries include anatomic considerations, gender, rate of development, growth, training errors, shoe wear, and running surface. Recent findings Most injuries in adolescent runners are overuse injuries rather than sudden traumatic events. Adolescent athletes are as prone as adults to poor form, poor habits, and poor training patterns. In addition, anatomic variants in the hindfoot, midfoot, and forefoot may predispose an athlete to specific injury. Summary Adolescent running injuries are common and becoming more frequent as trainers and athletes place increasing demands on the growing body. There is no evidence that this increased demand produces long-term adverse effects; however, a significant amount of time can be lost to injuries unless training patterns are constructed to allow for repair of the adolescent athlete.

Outcomes after standardized screw fixation technique of ankle arthrodesis.

Several methods of obtaining ankle fusion have been described, with numerous studies reporting on patient populations with varied diagnoses and various methods of fixation. This has led to outcome analyses that are difficult to interpret. Our hypothesis is that using a standard method of fusion, without the aid of allograft, a solid ankle fusion can be achieved in patients with end-stage ankle arthritis, and that this outcome can be reflected in standardized outcome tools. Forty-one consecutive ankle fusions in 40 patients were included in our study, with a minimum followup of 3 years. All patients had an ankle arthrodesis using two parallel retrograde 7.3-mm screws and local fibular graft. All but two patients obtained a solid talocrural union (95%), with a mean postoperative improvement in the American Orthopaedic Foot and Ankle Society score of 23 points. Results of our study showed that a simple technique based on sound mechanical and biologic principles can yield excellent outcomes for patients.Level of Evidence: Therapeutic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.