Accessory Flexor Hallucis Longus Tendon Discovered During Achilles Tendon Reconstruction: A Report of 2 Cases.

CASE: We present 2 cases of Achilles reconstruction using flexor hallucis longus (FHL) tendon transfer for the augmentation of Achilles surgical repair during which the patients were noted to have accessory FHL tendons. Structure identification in the posterior ankle is important because the neurovascular bundle is in close proximity to the FHL; knowledge of the anatomy of variations is helpful, and 2 cases of accessory tendon variation are reported. CONCLUSIONS: Achilles tears are typically primarily repaired. Some patients may require augmentation with allograft or autograft transfer of the FHL tendon. Accessory FHL tendons discovered during posterior approach to the Achilles has not been described in the literature.

Evaluation of posterior tibial pathology: comparison of sonography and MR imaging.

OBJECTIVE: To compare the results of sonographic (US) and magnetic resonance (MR) imaging in detecting pathology of the posterior tibial tendon (PTT) in patients with PTT dysfunction. DESIGN: Twenty-two ankles that were clinically suspected by the orthopedic surgeon to have PTT dysfunction were evaluated with US (10 MHz linear-array transducer) and 1.5 T MR examinations within the same day. The US and MR studies were conducted and interpreted by two sonologists and two musculoskeletal radiologists who were masked to the results of the other study. Four patients had bilateral studies. Classic clinical findings were utilized as a standard reference in staging PTT dysfunction. PATIENTS: Eighteen women (mean age 61 years, age range 39-86 years). RESULTS: Based on a commonly accepted staging system for PTT dysfunction, 6 ankles were classified as stage I, 11 ankles as stage II, and 5 ankles as stage III. All stage I ankles were interpreted as having an intact PTT by both MR imaging and US. In the stage II and III tendons, MR imaging demonstrated PTT tears in 12 of 22 examinations, including 11 partial tears and 1 complete tear. US demonstrated PTT tears in 8 of 22 examinations, including 8 partial tears and no complete tears. The findings of US and MR imaging were consistent in 17 of 22 cases (77%). The five inconsistencies were as follows: in 4 cases, US reported tendinosis when MR imaging interpreted partial tears (no change in management); in one case, US diagnosed a partial tear when MR reported a complete tear of the PTT (no change in management because the clinical findings were more consistent with a partial tear). CONCLUSIONS: In this study, US and MR imaging of the PTT were concordant in the majority of cases. US was slightly less sensitive than MR imaging for PTT pathology, but these discrepancies did not affect clinical management.

The effect of pulsed electromagnetic fields on hindfoot arthrodesis: a prospective study.

The aim of this study was to evaluate the effect of pulsed electromagnetic fields in a consecutive series of 64 patients undergoing hindfoot arthrodesis (144 joints). All patients who underwent elective triple/subtalar arthrodesis were randomized into control and pulsed electromagnetic field study groups. Subjects in the study group had an external pulsed electromagnetic fields device applied over the cast for 12 hours a day. Radiographs were taken pre- and postoperatively until radiographic union occurred. A senior musculoskeletal radiologist, blinded to the treatment scheme, evaluated the radiographic parameters. The average time to radiographic union in the control group was 14.5 weeks in 33 primary subtalar arthrodeses. There were 4 nonunions. The study group consisted of 22 primary subtalar arthrodeses and 5 revisions. The average time to radiographic union was 12.9 weeks (P =.136). The average time to fusion of the talonavicular joint in the control group was 17.6 weeks in 19 primary procedures. In the pulsed electromagnetic fields group of 20 primary and 3 revision talonavicular arthrodeses, the average time to radiographic fusion was 12.2 weeks (P =.003). For the 21 calcaneocuboid arthrodeses in control group, the average time to radiographic fusion was 17.7 weeks; it was 13.1 weeks (P =.010) for the 19 fusions in the study group. This study suggests that, if all parameters are equal, the adjunctive use of a pulsed electromagnetic field in elective hindfoot arthrodesis may increase the rate and speed of radiographic union of these joints.

The effect of posterior tibialis tendon dysfunction on the plantar pressure characteristics and the kinematics of the arch and the hindfoot.

OBJECTIVE: To study posterior tibialis tendon dysfunction using an in vitro model of the foot and ankle during the heel-off instant of gait. BACKGROUND: Previous studies have concentrated primarily on the effect of posterior tibialis tendon dysfunction on the kinematics of the hindfoot and the arch. METHODS: The specimens were loaded using a custom designed axial and tendon loading system and the location of the center of pressure was used to validate heel-off. Arch position, hindfoot position and plantar pressure data were recorded before and after the posterior tibialis tendon was unloaded. These data were recorded with the ligaments intact and after creating a flatfoot deformity. RESULTS: Unloading the posterior tibialis tendon caused significant posterior movement in the center of pressure for the intact and flatfoot conditions. This also resulted in a medial shift in the force acting on the forefoot. The forefoot loads shifted medially after a flatfoot was created even when the posterior tibialis tendon remained loaded. The spatial relationships of the bones of the arch and the bones of the hindfoot also changed significantly for the intact specimen, and to a lesser extent after a flatfoot. CONCLUSIONS: The posterior tibialis tendon plays a fundamental role in shifting the center of pressure anteriorly at heel-off. Posterior tibialis tendon dysfunction causes posterior shift in the center of pressure and abnormal loading of the foot's medial structures. This may be the reason that posterior tibialis tendon dysfunction leads to an acquired flatfoot deformity. Conversely, flatfoot deformity may be a predisposing factor in the onset of posterior tibialis tendon dysfunction. This tendon also acts to lock the bones of the arch and the hindfoot in a stable configuration at heel-off, but a flatfoot deformity compromises this ability.

Sprains about the foot and ankle encountered in the workmans' compensation patient.

Soft tissue injury in the workmans' compensation patient population has been previously poorly understood. Injuries that do not show up easily on radiographs are often undertriaged and undertreated. With the advent of improved imaging techniques, an enhanced understanding of soft tissue injuries has evolved over the past few years. Coupled with improved surgical and rehabilitation techniques, severely injured patients are able to experience remarkable recoveries. Many cannot return to previous function. These patients pose challenges to the astute clinician with regards to psychosocial issues relative to secondary gain. In addition, State-to-State variations in the workmans' compensation laws can confuse clinicians. Because of the protections and laws set in place in the United States, these patients can frequently be returned to the workforce as grateful and productive members of society.

Biomechanical evaluation of the efficacy of external stabilizers in the conservative treatment of acquired flatfoot deformity.

This study quantified and compared the efficacy of in-shoe orthoses and ankle braces in stabilizing the hindfoot and medial longitudinal arch in a cadaveric model of acquired flexible flatfoot deformity. This was addressed by combining measurement of hindfoot and arch kinematics with plantar pressure distribution, produced in response to axial loads simulating quiet standing. Experiments were conducted on six fresh-frozen cadaveric lower limbs. Three conditions were tested: intact-unbraced; flatfoot-unbraced; and flatfoot-braced. Flatfoot deformity was created by sectioning the main support structures of the medial longitudinal arch. Six different braces were tested including two in-shoe orthoses, three ankle braces and one molded ankle-foot orthosis. Our model of flexible flatfoot deformity caused the calcaneus to evert, the talus to plantarflex and the height of the talus and medial cuneiform to decrease. Flexible flatfoot deformity caused a pattern of medial shift in plantar pressure distribution, but minimal change in the location of the center of pressure. Furthermore, in-shoe orthoses stabilized both the hindfoot and the medial longitudinal arch, while ankle braces did not. Semi-rigid foot and ankle orthoses acted to stabilize the medial longitudinal arch. Based on these results, it was concluded that treatment of flatfoot deformity should at least include use of in-shoe orthoses to partially restore the arch and stabilize the hindfoot.

Safety and efficacy of the popliteal fossa nerve block when utilized for foot and ankle surgery.

The popliteal fossa nerve block (PFNB) offers numerous advantages that make it a suitable anesthetic technique for foot and ankle surgery. In this retrospective study, we investigated the acute and long-term safety and efficacy of this relatively underutilized anesthetic technique for foot and ankle surgery. A review of 834 patients who underwent foot and/or ankle surgery by the coauthor (NAA) was conducted. Four hundred sixty-seven patients received a PFNB with the aid of a peripheral nerve stimulator. Variables assessed included the quality of surgical anesthesia, postoperative analgesia and the acute and long-term incidence of postoperative neuralgia and neuropraxia. The PFNBs were performed by anesthesiologists with various levels of training at a tertiary care hospital and all were supplemented with a saphenous nerve block. The PFNB was successful as the sole anesthetic technique in 79% of the cases; 18% were converted to general anesthesia and 3% required augmentation with local anesthetic. There were no complications associated with the PFNB. There were no incidents of postoperative neuralgia or neuropraxia. Only 12% of patients with a successful block required analgesics in the PACU, while 60% of patients with a failed block required systemic analgesics for surgical site pain (p<0.01). These results suggest that the performance of the PFNB with the guidance of a peripheral nerve stimulator is a safe and effective anesthetic technique for foot and ankle surgery.