Lateralizing calcaneal osteotomy performed with a percutaneous burr results in a significantly lower increase in tarsal tunnel pressure.

PURPOSE: Tarsal tunnel syndrome is well documented following lateralizing calcaneal osteotomy to manage varus hindfoot deformity. Traditionally, calcaneal osteotomy is performed with an oscillating saw. No studies have investigated the effect of alternative surgical techniques on postoperative tarsal tunnel pressure. The purpose of this study was to investigate the difference in tarsal tunnel pressures following lateralizing calcaneal osteotomy performed using a high-torque, low-speed "minimally invasive surgery" (MIS) Shannon burr versus an oscillating saw. METHODS: Lateralizing calcaneal osteotomy was performed on 10 below-knee cadaveric specimens. This was conducted on 5 specimens each using an oscillating saw (Saw group) or MIS burr (Burr group). The calcaneal tuberosity was translated 1 cm laterally and transfixed using 2 Kirschner wires. Tarsal tunnel pressure was measured before and after osteotomy via ultrasound-guided percutaneous needle barometer. Mean pre/post-osteotomy pressures were compared between groups. Differences were analyzed using Student's t test. RESULTS: The mean pre-procedure tarsal tunnel pressure was 25.8 ± 5.1 mm Hg in the Saw group and 26.4 ± 4.3 mm Hg in the Burr group (p = 0.85). The mean post-procedure pressure was 63.4 ± 5.1 in the Saw group and 47.8 ± 4.3 in the Burr group (p = 0.01). Change in tarsal tunnel pressure was significantly lower in the Burr group (21.4 ± 4.5) compared to the Saw group (37.6 ± 12.5) (p = 0.03). The increase in tarsal tunnel pressure was 43% lower in the Burr group. CONCLUSION: In this cadaveric study, tarsal tunnel pressure increase after lateralizing calcaneal osteotomy was significantly lower when using a burr versus a saw. This is likely because the increased width ("kerf") of the 3 mm MIS burr, compared to the submillimeter saw blade width, causes calcaneal shortening. Given the smaller increase in tarsal tunnel pressure, using the MIS burr for lateralizing calcaneal osteotomy may decrease the risk of postoperative tarsal tunnel syndrome. Future research in vivo should explore this.

The Surgical Correction of Cavovarus Deformity in Charcot-Marie-Tooth Disease.

Charcot-Marie-Tooth (CMT) disease is the most commonly inherited neuropathy. CMT disease is a motor-sensory neuropathy with multiple genotypes. By comparison, the phenotypic expression is more uniform, with two main presentations. Most patients who need surgical care have progressive cavovarus foot deformity, with muscle imbalance causing a nonplantigrade foot, soft-tissue contractures, and abnormal bone morphology. Surgical treatment can be life-changing for these patients, allowing them to walk potentially brace free with more endurance and less pain. Early realignment procedures may reduce progression of joint arthritis. A minority of patients have diffuse paralysis below the knee. These patients are best treated with ground-reaction ankle-foot orthoses. This review article is based on the senior author's extensive experience with CMT, along with the limited evidenced-based literature.

Patient Satisfaction and Pain Relief After Deep Peroneal Nerve Neurectomy for Midfoot Arthritis: A Preliminary Short Report.

BACKGROUND: The deep peroneal nerve (DPN) plays a role in afferent nociceptive dorsal midfoot joint pain perception. DPN neurectomy for treatment of symptomatic dorsal midfoot osteoarthritis allows early mobilization and weightbearing. The purpose of our study was to evaluate the patient satisfaction and pain relief after DPN neurectomy for treatment of chronic dorsal midfoot pain due to osteoarthritis. METHODS: In this retrospective, IRB-approved, questionnaire-based study, we evaluated 48 patients (55 feet) with an average follow-up of 35.1 (range, 16-51) months who underwent DPN neurectomy at our institution between September 2017 and February 2021. There were 38 women and 10 men, 41 unilateral (22 right, 19 left) and 7 bilateral procedures, with an average age of 67.8 (range, 35-88) years at the time of surgery. A questionnaire that included questions regarding postsurgical dorsal midfoot pain relief, surgical result satisfaction, and current functional limitations was administered via telephone. Demographic information, patient responses, and complications were recorded. RESULTS: Of the 48 patients, 80.8% were satisfied with the result of the surgery in relieving their dorsal midfoot pain, 84.6% would repeat the surgery under the same circumstances, 83.8% would recommend the surgery to a friend, 10.4% reported they wish they had undergone arthrodesis, 91.7% reported pain relief in the first 6 months, and 55.6% reported current activity limitations. Six feet (10.9%) underwent a second procedure with an average postoperative time of 20.5 (range, 1-36) months. Complications included 1 hematoma and deep wound infection, 1 DPN neuroma and superficial peroneal nerve entrapment, and 4 patients with inadequate pain relief. CONCLUSION: In this cohort, DPN neurectomy appeared to be a reasonable surgical alternative to arthrodesis for the management of chronic dorsal midfoot pain due to midfoot osteoarthritis after failed nonoperative management. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Contemporary Review: Autograft Bone Use in Foot and Ankle Surgery.

Bone autografts are frequently harvested for use in foot and ankle surgery. A commonly used harvest site is the iliac crest; however, because of known morbidity with this site, the tibia and calcaneus are attractive alternatives. There remains limited understanding regarding the osteogenic potential of autografts from each of these locations. In this review, we provided an update of the known data on bone autografts from the iliac crest, tibia, and calcaneus, focusing on the total cells harvested from each site as well as the presence of osteogenic osteoprogenitor cells. Level of Evidence: Level V, expert opinion.

Accuracy of Pain Tolerance Self-assessment Versus Objective Pressure Sensitivity.

INTRODUCTION: Effective treatment of postoperative pain after elective surgery remains elusive, and the experience of pain can be variable for patients. The patient's intrinsic pain tolerance may contribute to this variability. We sought to identify whether there was a correlation between subjective report of intrinsic pain tolerance and objective measurement of pressure dolorimetry (PD). We also sought to identify whether a correlation existed between PD and Patient Reported Outcome Measurement Information System (PROMIS) scores of pain intensity, physical function, and mood. PD is a validated, objective method to assess pain tolerance. Markers of general mental and physical health are correlated with pain sensitization and may also be linked to pain tolerance. METHODS: PROMIS scores, dolorimetry measurements, and survey data were collected on 40 consecutive orthopaedic foot and ankle surgery patients at the initial clinic visit. Patients were included if they had normal sensation on the plantar foot and no prior surgery or plantar heel source of pain. RESULTS: Objective dolorimetry data reflecting 5/10 pain for the patients were 24 N/cm 2 (±8.9). Patients estimated their pain threshold as 7.3/10 (±2.1). No correlation was found between objective and subjective pain threshold identified. A moderate negative correlation of R = -0.44 was observed regarding PROMIS-M with dolorimetry data ( P < -0.05). PROMIS-M score >60 had a significant decrease in pain threshold to 15.9 ± 8.5 N/cm 2 compared with 25.7 ± 8.9 N/cm 2 for those who were less depressed with a PROMIS<60 ( P < 0.05). CONCLUSION: Subjective pain tolerance is not correlated with the patient's own objective pain threshold or markers of mental health and should not be used to assist clinical decision making. PROMIS-M is inversely correlated with objective pain. Higher PROMIS-M scores are associated with a lower objective pain threshold. LEVEL OF EVIDENCE: Level II-Lesser Quality Randomized Controlled Trial or Prospective Comparative Study.

Pedal Musculovenous Pump Activation Effectively Counteracts Negative Impact of Knee Flexion on Human Popliteal Venous Flow.

Knee scooters are commonly used for mobility instead of other devices. However, passive popliteal venous flow impedance has been observed with knee scooter usage ostensibly as a result of deep knee flexion. This study aimed to characterize the magnitude of impact knee flexion has on popliteal venous flow in relation to the degree of knee flexion when walking boot immobilized. Furthermore, the countervailing effect of standardized pedal musculovenous pump (PMP) activation was observed. Popliteal venous diameter and flow metrics were assessed with venous ultrasonography in 24 healthy individuals. Straight leg, crutch, and knee scooter positioning while wearing a walking boot and non-weight-bearing were compared. Flow was assessed with muscles at rest and with PMP activation. Of 24 participants, 16 (67%) were female. Twelve limbs (50%) were right sided. The mean age was 21.9 (SD = 3.0) years, and the mean body mass index was 21.9 (SD 1.9) kg/m2. Observer consistencies were excellent (intraclass correlation range = 0.93 to 0.99). No significant differences in mean vessel diameter, time-averaged mean velocity, and total volume flow occurred (all P > .01). Corresponding knee flexion effect sizes were small (range = -0.04 to -0.26). A significant decrease (-24%) in active median time-averaged peak velocity occurred between upright and crutch positions (20.89 vs 15.92 cm/s; P < .001) with a medium effect size (-0.51). PMP activation increased all flow parameters (all P < .001), and effect sizes were comparatively larger (>0.6) across all knee flexion positions.Clinical Significance: Knee flexion has a small to medium impact on popliteal venous return in healthy patients. Active toe motion effectively counters the negative effects of gravity and knee flexion when the ankle is immobilized.Levels of Evidence: Therapeutic, Level IV.

Evaluation and Management of Adult Footdrop.

Footdrop is a common musculoskeletal condition defined by weakness in ankle joint dorsiflexion. Although the etiology varies, footdrop is characterized by specific clinical and gait abnormalities used by the patient to overcome the loss of active ankle dorsiflexion. The condition is often associated with deformity because soft-tissue structures may become contracted if not addressed. Patients may require the use of special braces or need surgical treatment to address the notable level of physical dysfunction. Surgical treatment involving deformity correction to recreate a plantigrade foot along with tendon transfers has been used with notable success to restore a near-normal gait. However, limitations and postoperative dorsiflexion weakness have prompted investigation in nerve transfer as a possible alternative surgical treatment.

Measuring Deltoid Insufficiency After Supination-External Rotation Ankle Fracture With Lateral Talar Subluxation on Gravity Stress View.

BACKGROUND: Stress-view radiographs are frequently obtained to evaluate supination-external rotation (SER) variant ankle fractures. Measurement of the ankle medial clear space (MCS) is a surrogate of medial structure integrity as part of overall ankle stability. Measurement of the lateral talus displacement with respect to the incisura may be a sensitive and specific method to assess joint subluxation. METHODS: Retrospective review of acute SER-variant isolated lateral malleolar fractures with gravity stress views (GSVs) were performed for 103 patients. GSV analysis was performed with standardized measurements of the MCS, superior clear space (SCS), and 2 new novel measurements of lateral talus subluxation (LTS). Decision for surgery was obtained by surgeons who reviewed masked injury radiographs for predictive performance analysis of the LTS vs MCS. RESULTS: MCS, SCS, and LTS measurements were performed on 103 patients. Mean MCS, SCS, and LTS within the operative group was increased. MCS ≥5 mm and LTS >4 mm had equal sensitivity (95%), with higher specificity for LTS (75% vs 60%). Receiver operating characteristic analysis demonstrates an area under the curve of 0.786 for MCS ≥5 mm vs 0.918 for LTS >4 mm. CONCLUSION: We found LTS to be superior to MCS for medial ankle structure stability on gravity stress views of SER-variant ankle fractures. We propose this as a useful tool for clinicians to consider when evaluating SER-variant ankle fractures. LEVEL OF EVIDENCE: Level II, prospective comparative study of radiographs.

Influence of glenoid wear pattern on glenoid component placement accuracy in shoulder arthroplasty.

BACKGROUND: Accurate glenoid component placement in shoulder arthroplasty is often difficult even with the use of preoperative planning. Computer navigation and patient-specific guides increase component placement accuracy, but which patients benefit most is unknown. Our purpose was to assess surgeons' accuracy in placing a glenoid component in vivo using 3-dimensional preoperative planning and standard instruments among various glenoid wear patterns. METHODS: We conducted a retrospective review of 170 primary anatomic total shoulder arthroplasty (aTSA) and reverse total shoulder arthroplasty (rTSA) performed at a single institution. Commercially available preoperative planning software was used in all arthroplasties with multiplanar 2-dimensional computed tomography and a 3-dimensional implant overlay. After registration of intraoperative bony landmarks to the navigation system, participating surgeons with knowledge of the preoperative plan were blinded to the computer screen and attempted to implement their preoperative plan by simulating placement of a central-axis glenoid guide pin. Two hundred thirty-three screenshots of surgeon's simulated guide pin placement were included. Glenoid displacement, error in version and inclination, and overall malposition from the preoperatively planned target point were stratified by posterior wear status (with [Walch B2 or B3] or without [A1, A2, or B1]) and Walch classification (A1, A2, B1, B2, or B3). The glenoid component was considered malpositioned when version or inclination errors exceeded 10° or the starting point displacement exceeded 4 mm. RESULTS: For rTSA, errors in version were greater for glenoids with posterior wear compared with those without (8.1° ± 5.6° vs. 4.7° ± 4.0°; P < .001). On post hoc analysis, B2 glenoids had greater version error than A1, A2, and B1 glenoids. A greater proportion of glenoids undergoing rTSA that possessed posterior wear had an error in version >10° compared with those without (31% vs. 8%; P < .001). Consequently, glenoids undergoing rTSA with posterior wear were malpositioned at a greater rate compared with those without (73% vs. 53%). In contrast, glenoids undergoing aTSA with and without posterior wear did not differ based on displacement error, version error, inclination error, or malposition occurrence. CONCLUSIONS: Posterior glenoid bone loss more commonly resulted in glenoid version errors exceeding 10 degrees and component malposition in rTSA, but not for aTSA. Malposition was still relatively high in patients without significant posterior wear for both aTSA (36%) and rTSA (53%). Surgeons should consider alternate techniques beyond preoperative planning and standard instrumentation when performing shoulder arthroplasty in patients with posteriorly worn glenoids.

Abnormal Bone Morphology in Charcot-Marie-Tooth Disease.

BACKGROUND: Although long suspected, it has yet to be shown whether the foot and ankle deformities of Charcot-Marie-Tooth disease (CMT) are generally associated with abnormalities in osseous shape. Computed tomography (CT) was used to quantify morphologic differences of the calcaneus, talus, and navicular in CMT compared with healthy controls. METHODS: Weightbearing CT scans of 21 patients (27 feet) with CMT were compared to those of 20 healthy controls. Calcaneal measurements included radius of curvature, sagittal posterior tuberosity-posterior facet angle, and tuberosity coronal rotation. Talar measurements included axial and sagittal body-neck declination angle, and coronal talar head rotation. Surface-mesh model analysis of the hindfoot was performed comparing the average of the CMT cohort to the controls using a CT analysis software (Disior Bonelogic 2.0). Means were compared with a t test (P < .05). RESULTS: CMT patients had significantly less talar sagittal declination vs controls (17.8 vs 25.1 degrees; P < .05). Similarly, CMT patients had less talar head coronal rotation vs controls (30.8 vs 42.5 degrees; P < .001). The calcaneal radius of curvature in CMT patients was significantly smaller than controls (822.8 vs 2143.5 mm; P < .05). CMT sagittal posterior tuberosity-posterior facet angle was also significantly different from that of controls (60.3 vs 67.9 degrees respectively; P < .001).Surface-mesh model analysis demonstrated the largest differences in morphology at the navicular tuberosity, medial talar head, sustentaculum tali, and anterior process of the calcaneus. CONCLUSION: This is the first study to quantify the morphologic differences in hindfoot osteology seen in CMT patients. Patients identified with osseous changes of the calcaneus, especially a smaller axial radius of curvature, may benefit from a 3-dimensional osteotomy for correction.